Additive manufacturing using resins with variable temperature control

Abstract

This application discloses additive manufacturing using resins with variable temperature control. Systems and processes for controlling multiple temperatures in additive manufacturing are provided herein. Such temperature control modulates polymer properties and facilitates the processing of materials to form 3D objects. The systems and processes disclosed herein also facilitate the processing of materials that are typically difficult to handle and deliver these materials to a photopolymerization zone configured to photopolymerize the materials into 3D objects via a layer-by-layer process. Such processes may include the steps of heating the resin to a flowable temperature, applying the resin to a carrier, cooling the film to increase the viscosity of the resin or to solidify the resin, and applying the resin-containing film to the area to be printed, followed by photopolymerization of the film. Resins and associated polymer materials are also provided herein, the properties of which can be modulated by exposure to more than one temperature zone. The formed polymer may include multiple regions of polymer material, each region independently possessing different properties. Processes and systems configured to produce polymer materials with multiple regions possessing different properties from a single-component formulation are also provided herein.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 071,124, filed August 27, 2020, the entire contents of which are incorporated herein by reference. Background Technology

[0003] 3D printers are essential devices for producing polymer 3D objects. Materials (such as polymeric resins) are typically combined in a layer-by-layer process, and then the material is solidified to form a 3D object. This additive manufacturing process enables the creation of complex and useful structures. Summary of the Invention

[0004] This document provides systems and processes for providing controlled and variable temperature zones for use in additive manufacturing of polymer materials. This temperature control enables the tuning and control of polymer properties and facilitates the processing of materials to form 3D polymer objects. The systems and processes disclosed herein also facilitate the processing of materials that are typically difficult to process, such as solid resins, and the delivery of these materials to a photopolymerization zone configured to photopolymerize the material into a three-dimensional object in a layer-by-layer process. As further described herein, such processes may include the steps of heating the resin to a flowable temperature, applying the resin to a carrier (e.g., a film), cooling the film to increase the viscosity of the resin or to solidify the resin, and applying the resin-containing film to a printed area, followed by photocuring the film. Unused resin can also be reused through this process, as described herein.

[0005] This document also provides resins and related polymer materials having properties that are adjustable upon exposure to more than one temperature range. In some embodiments, the formed polymer comprises multiple regions of a polymer material, each region independently possessing different properties. This document also provides processes and systems configured to produce polymer materials having multiple regions with different properties (e.g., such as composite materials or multiphase systems) from a single-component formulation.

[0006] As further described herein, the physical properties of the resulting polymerized material are controllable by selectively heating or cooling regions of the resin prior to (or during) polymerization. In some embodiments described herein, the process is performed on a layer-by-layer basis, and the material and / or polymer properties of the printed 3D polymer object are controlled in three dimensions. This disclosure partially provides for printed objects having different moduli (e.g., glass transition temperature, elasticity, water absorption, and hardness) in different regions (e.g., phases in a multiphase system).

[0007] In various aspects, this disclosure provides a method for producing a polymer material, the method comprising: providing a resin; controlling the temperature of the resin, the resin comprising: a first region having a first temperature; and a second region having a second temperature; and polymerizing the resin to form a polymer material. In some aspects, the temperature of the resin is controlled spatially. In some aspects, the temperature of the resin is controlled spatially in the xy-dimension. In some aspects, the temperature of the resin is controlled spatially perpendicular to a photocuring light source. In some aspects, the temperature of the resin is controlled spatially in the x-dimension, y-dimension, and / or z-dimension. In some aspects, the z-dimension is the direction of light emitted from the photocuring light source.

[0008] In some aspects, polymerizing a polymer material also includes generating a first polymeric region and a second polymeric region. In some aspects, the first polymeric region has at least one property that differs from the second polymeric region, the at least one property being selected from the group consisting of elongation at break, storage modulus, tensile modulus, residual stress, color, transparency, hydrophobicity, lubricity, surface texture, percentage of crystallinity, and phase composition ratio.

[0009] In some aspects, temperature control includes heating or cooling the resin in the first region to a first temperature. In some aspects, temperature control includes heating or cooling the resin in the second region to a second temperature. In some aspects, heating the resin in the first region and / or heating the resin in the second region includes exposure to a light source. In some aspects, the light source is an infrared light source. In some aspects, the difference between the first temperature and the second temperature is 5°C or greater, 10°C or greater, 15°C or greater, 20°C or greater, 30°C or greater, 40°C or greater, 50°C or greater, or greater than 50°C.

[0010] In some respects, resin polymerization includes photopolymerization.

[0011] In some aspects, the method for producing polymeric materials also includes providing a mask. In some aspects, the method for producing polymeric materials also includes thermosetting polymeric materials. In some aspects, the method for producing polymeric materials also includes photocuring polymeric materials. In some aspects, the method for producing polymeric materials also includes applying resin to a substrate. In some embodiments, the substrate comprises a fluoropolymer. In some aspects, the method for producing polymeric materials also includes manufacturing an object. In some aspects, the manufacturing includes printing resin using a 3D printer. In some aspects, the manufacturing includes stereolithography, digital light processing, two-photon induced photopolymerization, inkjet printing, multi-jet printing, fused deposition modeling, or any combination thereof. In some aspects, the object includes a plurality of regions having at least one distinct property selected from the group consisting of elongation at break, storage modulus, tensile modulus, residual stress, glass transition temperature, water absorption, hardness, color, transparency, hydrophobicity, lubricity, surface texture (e.g., surface finish – matte, glossy), crystallinity percentage, and phase composition ratio. In some aspects, multiple regions each have a size dimension of less than 250 μm, less than 200 μm, less than 150 μm, less than 100 μm, less than 90 μm, less than 80 μm, less than 70 μm, less than 60 μm, less than 50 μm, less than 40 μm, less than 30 μm, less than 20 μm, or less than 10 μm. In some aspects, the voxel size of any particular region has one to three size dimensions of less than 1000 μm, less than 500 μm, less than 250 μm, less than 200 μm, less than 150 μm, less than 100 μm, less than 90 μm, less than 80 μm, less than 70 μm, less than 60 μm, less than 50 μm, less than 40 μm, less than 30 μm, less than 20 μm, or less than 10 μm.

[0012] In some aspects, the resin comprises a crystalline material and one of the first or second regions comprises a crystalline material in molten form. In some aspects, the resin is homogeneous. In some aspects, the resin phase separates into two or more phases prior to polymerization. In some aspects, the resin phase separates upon temperature change. In some aspects, the resin phase separates during photopolymerization.

[0013] In some respects, the resin comprises multiple monomers, most of which are copolymerized at a first temperature and homopolymerized at a second temperature.

[0014] In some respects, controlling the temperature of the resin initiates secondary chemical reactions. These secondary chemical reactions include ionothermal reactions, epoxide polymerization, ionothermal polymerization, bond breaking reactions, bond formation reactions, catalyst activation, or any combination thereof.

[0015] In some respects, the object is an orthodontic appliance. In some respects, an orthodontic appliance is a brace, expander, or spacer. In some respects, an orthodontic appliance comprises multiple tooth-accommodating cavities configured to reposition teeth from a primary configuration to a secondary configuration. In some respects, an orthodontic appliance is one of multiple orthodontic appliances configured to reposition teeth from an initial configuration to a target configuration. In some respects, an orthodontic appliance is one of multiple orthodontic appliances configured to reposition teeth from an initial configuration to a target configuration according to a treatment plan. In some respects, an orthodontic appliance is a brace.

[0016] In various aspects, this disclosure provides polymer materials formed by the methods disclosed herein for producing polymer materials. In some aspects, the polymer material is characterized by one or more of the following: elongation at break greater than or equal to 5%; storage modulus greater than or equal to 500 MPa; tensile modulus greater than or equal to 500 MPa; residual stress greater than or equal to 0.01 MPa; and flexural modulus greater than or equal to 60 MPa after immersion in water for 24 hours. In some aspects, the polymer material is characterized by an elongation at break greater than or equal to 5%. In some aspects, the polymer material is characterized by a storage modulus greater than or equal to 500 MPa. In some aspects, the polymer material is characterized by a tensile modulus greater than or equal to 500 MPa. In some aspects, the polymer material is characterized by a residual stress greater than or equal to 0.01 MPa. In some aspects, the polymer material is characterized by a flexural modulus greater than or equal to 60 MPa after immersion in water for 24 hours. In some aspects, the polymer material is characterized by a residual stress of 5% to 45% of the initial load, or a residual stress of 20% to 45% of the initial load. In some respects, polymeric materials are characterized by tensile modulus ranging from 500 MPa to 2000 MPa or tensile modulus ranging from 800 MPa to 2000 MPa.

[0017] In some respects, polymeric materials are characterized by the following: elongation at break greater than or equal to 5%; storage modulus greater than or equal to 500 MPa; tensile modulus greater than or equal to 500 MPa; and residual stress greater than or equal to 0.01 MPa.

[0018] In some aspects, polymeric materials are characterized by the following: elongation at break greater than 10%, elongation at break greater than 20%, elongation at break greater than 30%, elongation at break from 5% to 250%, elongation at break from 20% to 250%, or elongation at break between 40% and 250%. In some aspects, polymeric materials are characterized by the following: storage modulus from 0.1 MPa to 4000 MPa, storage modulus from 300 MPa to 3000 MPa, or storage modulus from 750 MPa to 3000 MPa. In some aspects, polymeric materials are characterized by residual stress from 0.01 MPa to 15 MPa, or residual stress from 2 MPa to 15 MPa. In some aspects, residual stress is measured after immersion in an aqueous solution for 24 hours.

[0019] In various aspects, this disclosure provides an object comprising: a first region comprising a first plurality of monomers, the first region being characterized by a first set of physical properties; and a second region comprising a second plurality of monomers, the second region being characterized by a second set of physical properties, wherein the first plurality of monomers and the second plurality of monomers are similar, while the first set of physical properties and the second set of physical properties are different. In some aspects, the first plurality of monomers and the second plurality of monomers are substantially identical. In some aspects, the object is formed from a single resin. In some aspects, the single resin is homogeneous.

[0020] In some aspects, the object also includes a third region comprising a third plurality of monomers and characterized by a third set of physical properties, wherein the first plurality of monomers, the second plurality of monomers, and the third plurality of monomers are similar, while the first set of physical properties, the second set of physical properties, and the third set of physical properties are different from each other. In some aspects, the first plurality of monomers, the second plurality of monomers, and the third plurality of monomers are substantially the same. In some aspects, the third region is more amorphous than the first and second regions.

[0021] In various aspects, this disclosure provides a system for forming an object, the system comprising: a resin injector configured to dispense resin; a first temperature control element; a light source; a build platform configured to hold the object; and a carrier platform configured to deliver resin from the resin injector to the first temperature control element, the light source, and the build platform.

[0022] In various aspects, this disclosure provides a system for forming an object, the system comprising: a printhead including: a resin injector configured to dispense resin, a first temperature control element, and a light source; and a build platform configured to hold the object. In some aspects, the printhead is configured to dispense resin onto the build platform to form a deposited layer. In some aspects, the printhead is configured to dispense resin onto the deposited layer. In some aspects, the printhead includes a plurality of resin injectors, each configured to dispense an individual resin. In some aspects, the printhead further includes an infrared heating element. In some aspects, the printhead is configured to move horizontally. In some aspects, the printhead is configured to move horizontally in a two-dimensional plane. In some aspects, the printhead is configured to move vertically. In some aspects, the printhead is configured to move in three spatial dimensions.

[0023] In some aspects, the construction platform is configured to move horizontally, horizontally in a two-dimensional plane, vertically, or in three spatial dimensions. In some aspects, a first temperature control element is located after the resin injector and configured to lower the resin temperature. In some aspects, the first temperature control element is located after a thickness controller and configured to lower the resin temperature. In some aspects, the first temperature control element is located within the resin injector and configured to raise the resin temperature. In some aspects, the first temperature control element includes a cooling plate. In some aspects, the cooling plate is connected to a chiller or thermoelectric cooling system. In some aspects, the resin injector heats the resin.

[0024] In some aspects, the system for forming the object also includes a second temperature control element. In some aspects, the second temperature control element is configured to increase the temperature of the resin. In some aspects, the second temperature control element includes a heater. In some aspects, the second temperature control element is a remelter. In some aspects, the second temperature control element includes a light source.

[0025] In some aspects, the carrier platform is configured to move along the horizontal plane at a first rate, and the construction platform is configured to move along the horizontal plane at a second rate, the first rate being substantially similar to the second rate. In some aspects, the construction platform is configured to apply pressure to the carrier platform or receive pressure from the carrier platform.

[0026] In some aspects, the resin injector is configured to dispense resin in a heated form. In some aspects, the carrier platform is a membrane. In some aspects, the light source is configured to emit ultraviolet light, infrared light, visible light, or any combination thereof.

[0027] In some respects, the system used to form the object also includes a layer thickness controller. In some respects, the layer thickness controller includes a doctor blade.

[0028] In some respects, the carrier platform is configured to repeatedly apply resin to the build platform and / or apply resin to the build platform.

[0029] In some aspects, the second temperature control element is configured to heat the uncured resin attached to the carrier platform. In other aspects, the second temperature control element is configured to heat the uncured resin after the carrier platform has passed through the construction platform.

[0030] In some respects, the system is configured to recycle uncured resin.

[0031] In some aspects, the system for forming the object also includes an infrared heating element. In some aspects, the infrared heating element is configured to heat a region of the resin. In some aspects, this region is heated to a temperature relatively higher than that of a portion of the resin outside this region. In some aspects, the infrared heating element is located below the carrier platform. In some aspects, the infrared heating element is located above the carrier platform. In some aspects, the infrared heating element is configured to emit microwave light.

[0032] In some aspects, the system for forming the object also includes a particulate applicator. In some aspects, the particulate applicator is a funnel or a sprayer. In some aspects, the particulate applicator is configured to apply a binder-enhancing agent to the resin. In some aspects, the binder-enhancing agent includes a powdered binder-enhancing agent or a liquid binder-enhancing agent. In some aspects, the binder-enhancing agent includes an infrared absorbing compound, carbon black, a dye, a multiphoton absorber, metal particles, nanoparticles, water absorbed into silica, or any combination thereof. In some aspects, the binder-enhancing agent includes a binder and / or a monomer system. In some aspects, the particulate applicator is configured to apply a light absorber to the resin. In some aspects, the light absorber is applied as a thin layer. In some aspects, the light absorber is applied to at least one side of the resin. In some aspects, the light absorber is applied to one side of the resin. In some aspects, the light absorber is applied to at least both sides of the resin. In some aspects, the light absorber is applied to both sides of the resin. In some aspects, the particulate applicator is also configured to apply adhesive enhancers, adhesive monomers, or combinations thereof. In some aspects, the particulate applicator is configured to apply adhesion resistors to the resin. In some aspects, the adhesion resistors prevent the resin layers from sticking together.

[0033] In some aspects, the carrier platform is configured to transport uncured resin from the build platform to the resin injector. In other aspects, the carrier platform is configured to transport uncured resin from the build platform to the remelter and from the remelter to the resin injector.

[0034] In some respects, the carrier platform is configured to move along a horizontal plane, and the construction platform is configured to move along a vertical plane.

[0035] In some respects, the system for forming objects also includes: a first feed roll configured to dispense a carrier platform without resin, and a first take-up reel configured to receive a carrier platform carrying uncured resin.

[0036] In some aspects, the first temperature control element includes a cooling plate, a fan, a water bath, a cooling roller, or any combination thereof. In some aspects, the first temperature control element is supplied with air, an inert gas, or a rapidly evaporating material. In some aspects, the rapidly evaporating material includes butane, liquid nitrogen, solid carbon dioxide, or combinations thereof.

[0037] In some respects, the resin injector and the first temperature control device are located between the first feed roll and the first reel. In other respects, a second temperature control device, a microparticle applicator, or a combination thereof are located between the first feed roll and the first reel.

[0038] In some aspects, the system for forming the object also includes a second feed roll and a second reel. In some aspects, the first reel is the second feed roll. In some aspects, the build platform is configured to receive resin from a carrier platform. In some aspects, a light source and the build platform are located between the second feed roll and the second reel. In some aspects, an infrared heating element is located between the second feed roll and the second reel.

[0039] In some aspects, the system for forming an object also includes a window located between the light source and the build platform. In some aspects, the system for forming an object also includes a cutting device. In some aspects, the cutting device includes a molding cutter, a laser cutter, a blade, other cutting devices, or other cutting mechanisms. In some aspects, the cutting device is configured to cut uncured resin into a plurality of uncured resin sheets. In some aspects, the system for forming an object also includes a robotic arm configured to move at least some of the plurality of uncured resin sheets. In some aspects, the robotic arm is configured to move at least some of the plurality of uncured resin sheets to the build platform. In some aspects, the system for forming an object also includes a storage device configured to store the plurality of uncured resin sheets. In some aspects, the system for forming an object also includes a mask.

[0040] In some respects, the object is an orthodontic appliance. In some respects, an orthodontic appliance is a brace, expander, or spacer. In some respects, an orthodontic appliance includes multiple tooth-receiving cavities configured to reposition teeth from a primary form to a secondary form. In some respects, an orthodontic appliance is one of multiple orthodontic appliances configured to reposition teeth from an initial form to a target form. In some respects, an orthodontic appliance is one of multiple orthodontic appliances configured to reposition teeth from an initial form to a target form according to a treatment plan. In some respects, an orthodontic appliance is a brace.

[0041] In various respects, this disclosure provides a method for forming a cured polymer material, the method comprising using a system for forming an object as disclosed herein.

[0042] In various aspects, this disclosure provides a method for forming a cured polymer material, the method comprising: heating a resin; applying the resin to a carrier platform; adjusting the temperature of the applied resin using a first temperature control element; applying the resin to a receiving element; and curing at least a portion of the resin to form a cured polymer material.

[0043] In some aspects, the resin is heated to a flowable temperature. In some aspects, the carrier platform is a membrane. In some aspects, temperature adjustment includes cooling the resin. In some aspects, the region includes a construction platform. In some aspects, the region includes an applied layer of resin on top of the construction platform. In some aspects, at least a portion of the cured resin includes exposure to a light source.

[0044] In some aspects, the method of forming a cured polymeric material further includes transporting resin from a resin injector to a first temperature-controlled element, from the first temperature-controlled element to a build platform, from the first temperature-controlled element to a light source, or any combination thereof. In some aspects, the method of forming a cured polymeric material further includes transporting an uncured portion of the resin from the light source and / or from the build platform to a second temperature-controlled device. In some aspects, the second temperature-controlled device heats the uncured portion of the resin to melt it. In some aspects, at least a portion of the cured resin comprises photopolymerization.

[0045] In various aspects, this disclosure provides a method for polymerizing a resin, the method comprising: applying a first temperature to the resin; applying a second temperature to the resin; and curing at least a portion of the resin to form a cured polymer material. In some aspects, the method for polymerizing a resin further includes manufacturing an object. In some aspects, manufacturing includes printing the resin using a 3D printer. In some aspects, manufacturing includes stereolithography, digital light processing, two-photon induced photopolymerization, inkjet printing, multi-jet printing, fused deposition modeling, or any combination thereof.

[0046] In some respects, the first part of the resin is cured at a first temperature. In other respects, the second part of the resin is cured at a second temperature.

[0047] In some respects, the method of polymerizing the resin also includes placing a first resin layer on top of a second resin layer.

[0048] In some aspects, the method of polymerizing the resin further includes applying pressure to at least one of the first resin layer or the second resin layer. In some aspects, applying pressure adheres the first resin layer to the second resin layer.

[0049] In some respects, the method for polymerizing resins also includes repeatedly constructing resin layers.

[0050] In some aspects, the object comes into contact with a portion of the uncured resin. In some aspects, the object is surrounded by uncured resin. In some aspects, the method of polymerizing the resin also includes removing the uncured resin. In some aspects, removing the uncured resin includes heating the object. In some aspects, removing the uncured resin includes applying microwave energy. In some aspects, removing the uncured resin includes using a solvent.

[0051] Merging by reference

[0052] All publications, patents and patent applications mentioned in this specification are incorporated herein by reference as if each individual publication, patent or patent application were specifically and individually indicated for inclusion by reference. Attached Figure Description

[0053] The novel features of the invention are particularly set forth in the appended claims. The features and advantages of the invention will be better understood by referring to the following detailed description and accompanying drawings, which illustrate illustrative embodiments utilizing the principles of the invention, as shown in the drawings:

[0054] Figure 1A A tooth repositioning device according to an embodiment is shown.

[0055] Figure 1B A tooth repositioning system according to an embodiment of the present disclosure is shown.

[0056] Figure 1C An orthodontic treatment method using multiple instruments according to an embodiment of the present disclosure is illustrated.

[0057] Figure 2 A method for designing orthodontic devices according to embodiments of the present disclosure is shown.

[0058] Figure 3 A method for digitally planning orthodontic treatment according to an embodiment of the present disclosure is shown.

[0059] Figure 4 The treatment generated and implemented according to embodiments of this disclosure is illustrated.

[0060] Figure 5 An embodiment of a system is shown, which is configured to control the temperature during the formation of a printed object, wherein unused, uncured resin is removed from the object being constructed.

[0061] Figure 6 An embodiment of a system is shown, which is configured to control temperature during the formation of a printed object and includes means configured to apply additional components to a resin and an infrared heater.

[0062] Figure 7 An embodiment of a system is shown, which is configured to control the temperature during the formation of a printed object, wherein unused, uncured resin is deposited along with the object being constructed.

[0063] Figure 8 An embodiment of the system is shown, which is configured to control the temperature during the formation of a printed object, wherein a roll of resin is formed in a resin forming step, and the roll of resin is used to form the printed object in a printing step.

[0064] Figure 9 An embodiment of the system is shown, which is configured to control temperature during the formation of a printed object, wherein resin slits are formed in a resin forming step, and the resin slits are used to form the printed object in a printing step.

[0065] Figure 10 An embodiment of a system is shown, which is configured to control temperature during the formation of a printed object, wherein a printhead is used to control multiple processes.

[0066] Figure 11A Two pieces of solid resin are shown, and Figure 11B This shows two pieces of resin bonded together by applying pressure.

[0067] Figure 12A Two pieces of solid resin are shown being heated; Figure 12B The image shows two pieces of resin bonded together. Figure 12C The mask used during photopolymerization is shown; Figure 12D A sample of the material is shown, with the cured and uncured areas outlined. Figure 12E The sample of the polymer material that was separated is shown; Figure 12F This demonstrates the robustness of the polymer material at high temperatures; Figure 12G The image shows a post-cured polymer material.

[0068] Figure 13AAn uncured resin sample with a relatively low temperature region (left) and a relatively high temperature region (right) is shown. Figure 13B The image shows an uncured resin including filler and having a relatively low temperature region (left) and a relatively high temperature region (right); Figure 13C The image shows a cured polymer material that is cured simultaneously in a resin having a relatively low temperature region (left), a relatively high temperature region (right), and an amorphous region in between (off-center left).

[0069] Figure 14 The differences in physical data from the cured polymer material are shown when the resin is at a relatively cold temperature or a relatively hot temperature. Detailed Implementation

[0070] Traditional additive manufacturing (3D) printers (e.g., digital light processing (DLP) printers and stereolithography (SLA) printers) have limited selectivity in temperature control. Typical 3D printers operate at a single set temperature (e.g., at room temperature, within a defined heating range, or within a defined cooling range). Traditional additive manufacturing printers also form polymer materials whose mechanical or polymeric properties change little or not at all in the printed product. These typical 3D printers also generate a significant amount of associated waste, as the resin is often difficult or impossible to reuse once it has passed through the system. Partly due to these limitations, traditional 3D printers are restricted in the materials they can process, the products they can output, and the physical properties of the products they produce.

[0071] This disclosure provides systems and methods for forming printed objects (i.e., 3D printed objects) and polymeric materials produced therefrom. The additive manufacturing systems described herein control the temperature of the resin during the manufacturing process to provide a product with controlled physical and material properties. This disclosure also provides methods for controlling the temperature of the resin during the formation of the polymeric material. Furthermore, this disclosure provides methods for using the systems described herein. Additionally, this disclosure provides materials used in the methods and systems described herein, as well as objects formed by the materials, methods, and systems described herein. Although not limited in its application, this disclosure provides orthodontic appliances formed by the materials, methods, and systems described herein.

[0072] Systems and processes for creating printable objects

[0073] This disclosure provides systems and methods for forming polymer materials from resins by regionally controlling temperature. In some embodiments, this disclosure provides a system for forming an object, the system comprising:

[0074] A resin injector configured to dispense resin;

[0075] First temperature control element;

[0076] light source;

[0077] The platform is built and configured to retain objects; and

[0078] A carrier platform is configured to deliver resin from a resin injector to a first temperature control element, a light source, and a build platform. Exemplary embodiments of such a system are provided herein. In some embodiments, the resin injector is a heated resin injector.

[0079] In some embodiments, this disclosure provides a system for forming objects, the system comprising:

[0080] A resin injector configured to dispense resin, optionally wherein the resin injector is a heated resin injector;

[0081] At least one temperature control element;

[0082] At least one light source;

[0083] The platform is built and configured to retain objects; and

[0084] A carrier platform configured to deliver resin from a resin injector to at least one temperature control element, at least one light source, and a build platform.

[0085] In some embodiments of the systems disclosed herein, the light source comprises electromagnetic radiation. In some embodiments, the light source includes wavelengths for curing photopolymerizable resins (e.g., the resins described herein). In some embodiments, the light source includes wavelengths less than 700 nm.

[0086] In some embodiments of the system disclosed herein, the first temperature control element is a first cooling element and is configured to reduce the temperature of the resin. In some embodiments, the first cooling element is positioned between the resin injector and the light source along a path of the carrier platform, and the first cooling element is configured to reduce the temperature of the resin. In some embodiments, the system further includes a layer thickness controller. In some embodiments, the first cooling element is positioned between the layer thickness controller and the light source along a path of the carrier platform, and the first cooling element is configured to reduce the temperature of the resin. In embodiments, the first cooling element includes a cooling plate. In some embodiments, the cooling plate is connected to a cooler or a thermoelectric cooling system. In some embodiments, the first temperature control element includes a cooling plate, a fan, a water bath, a cooling roller, or any combination thereof. In some embodiments, the first temperature control element is configured to apply air, an inert gas, or a rapidly evaporating material. In some embodiments, the first cooling element includes a cooling plate, a fan, a water bath, a cooling roller, or any combination thereof. In some embodiments, the first cooling element is configured to apply air, an inert gas, or a rapidly evaporating material. In some embodiments, a rapidly evaporating material is applied to cool the resin as the material evaporates from the resin surface. In some embodiments, the rapidly evaporating material includes butane, liquid nitrogen, solid carbon dioxide (e.g., CO2 snow), or combinations thereof.

[0087] In some embodiments of the systems disclosed herein, the first temperature control element is a first heating element configured to increase the temperature of the resin. As a non-limiting example, the first temperature control element may be configured to heat resin, for example, within a resin injector. In some embodiments, the first temperature control element is a first heating element. In some embodiments, the resin injector heats the resin. In some embodiments, the resin injector is configured to dispense resin in a heated form.

[0088] In some embodiments of the system disclosed herein, the system further includes a second temperature control element. In some embodiments, the second temperature control element is a first cooling element as described herein. In some embodiments, the second temperature control element is a first heating element as described herein. In some embodiments, the second temperature control element includes a heater. In some embodiments, the second temperature control element is a remelter (i.e., a heating element configured to melt resin). In some embodiments, the second temperature control element includes a light source and is configured to provide irradiation (e.g., infrared or microwave irradiation).

[0089] In some embodiments of the system disclosed herein, the system includes: a first temperature control element for increasing the temperature of the resin (e.g., within or near a resin injector), a second temperature control element for decreasing the temperature of the resin (e.g., a first cooling element), and a third temperature control element for increasing the temperature of the resin (e.g., a heater, a remelter, or a light source). In some embodiments, the third temperature control element is a remelter for heating uncured resin attached to a carrier platform. In some embodiments, the remelter is configured to heat the uncured resin after the carrier platform has passed through the construction platform.

[0090] In some embodiments of the system disclosed herein, the resin injector does not heat the resin, and the system includes a first temperature control element (e.g., a first cooling element) to lower the resin temperature and a second temperature control element (e.g., a heater, remelter, or light source) to raise the resin temperature. In some embodiments, the second temperature control element is a remelter that heats the uncured resin attached to the carrier platform. In some embodiments, the remelter is configured to heat the uncured resin after the carrier platform has passed through the construction platform.

[0091] In some embodiments of the systems disclosed herein, a carrier platform (e.g., a carrier membrane) is configured to move along a horizontal plane at a first rate. In some embodiments, a build platform is configured to move along a horizontal plane at a second rate. In some embodiments, the first rate and the second rate are substantially similar, such that the carrier platform (e.g., the carrier membrane) moves in substantially the same direction and at substantially the same rate as the build platform. In this way, while the carrier platform is in transport, the carrier platform can deposit resin onto the build platform or onto a previous layer already deposited on the build platform.

[0092] In some embodiments of the systems disclosed herein, the carrier platform is a membrane (i.e., a carrier membrane). In some embodiments, the build platform is configured to apply pressure to the carrier platform. For example, in some embodiments, the build platform is configured to move vertically to provide pressure to the carrier platform (e.g., the carrier membrane) to facilitate the deposition of resin from the carrier platform to the build platform or a previous layer already deposited on the build platform. In some embodiments, the carrier platform is configured to apply pressure to the build platform. For example, in some embodiments, the carrier platform is configured to move vertically to provide pressure to the build platform to facilitate the deposition of resin from the carrier platform to the build platform or a previous layer already deposited on the build platform. In some embodiments of the systems disclosed herein, the carrier platform is configured to repeatedly apply resin to the build platform and / or resin layers previously applied to the build platform. In some embodiments of the systems disclosed herein, the build platform is configured to receive resin from the carrier platform (e.g., the carrier membrane).

[0093] In some embodiments of the system disclosed herein, the system is configured to apply pressure to two or more layers of resin (e.g., resin sheets). In some embodiments, the system is configured to apply pressure when at least one of the two or more layers of resin is close to the melting point of the resin. In some embodiments, pressure is applied when at least one layer is within a resin melting temperature of 80°C, 70°C, 60°C, 50°C, 40°C, 30°C, 20°C, 10°C, or 5°C. In some embodiments, the application of pressure is configured to cause at least some of the resin to melt. In some embodiments, the application of pressure is configured to bond the layers of resin (e.g., by melting at least a portion of the resin, such as the surface interface between two layers).

[0094] In some embodiments, pressure is applied while at least two layers of the resin are uncured. In some embodiments, pressure is applied uniformly to the at least two layers (e.g., by using a flat object). (As a non-limiting example, e.g.) Figure 8 (The window shown herein) applies pressure. In some embodiments of the systems disclosed herein, a window or other flat, translucent or transparent component is located between a light source and an uncured resin layer. In some embodiments, the window or other flat, translucent or transparent component is configured to provide uniform pressure to the at least two layers. In some embodiments, the window or other flat, translucent or transparent component is attached to a moving device such that the window or other flat, translucent or transparent component is configured to move and thereby apply pressure to at least one of the at least two layers of resin. In some embodiments, the systems disclosed herein include means for applying pressure to the at least two layers of resin (e.g., uncured resin) before irradiation with a light source (e.g., before photopolymerization). In some embodiments, the means for applying pressure is spatially located away from the light source. In some embodiments, the means for applying pressure is located near the light source (e.g., as shown in the image). Figure 8 (As shown). The amount of pressure applied to the at least two layers of resin is sufficient to bond the resin layers together. The amount of pressure may depend on the temperature of the resin, the viscosity of the resin, the melting temperature of the resin, or other factors. In some embodiments, the resin described herein is thixotropic (i.e., flows under pressure but remains in place without said pressure). In some embodiments, it is preferred that a small amount of pressure is required to bond the resin layers together.

[0095] In some embodiments of the systems disclosed herein, the resin (e.g., uncured resin) is configured to at least partially melt upon application of pressure. In some embodiments, the resin used herein (e.g., uncured resin) is configured such that a small amount of pressure causes at least some melting when near its melting point. In some embodiments, this at least some melting is configured to laminate two layers of resin together. As a non-limiting example, the two layers of resin (e.g., uncured resin) to which pressure is applied may at least partially melt at the interface between the two layers, thereby laminating these layers together. The closer the temperature of the resin is to its melting point, the less force or time is required to apply sufficient pressure to laminate the layers together. In some embodiments of the systems disclosed herein, the resin layers are exposed to a light source after lamination. In some embodiments, exposing the resin layers to light after applying pressure (e.g., laminating the layers) (e.g., photopolymerizing the resin) causes permanent attachment of the two layers.

[0096] In some embodiments of the systems disclosed herein, the light source is configured to emit electromagnetic radiation. In some embodiments of the systems disclosed herein, the light source is configured to emit ultraviolet light, infrared light, visible light, or any combination thereof. In some embodiments of the systems disclosed herein, the system also includes a layer thickness controller. In some embodiments, the layer thickness controller includes a blade or roller. In some embodiments of the systems described herein, the system is configured to recycle uncured resin.

[0097] In some embodiments of the system disclosed herein, the system includes an infrared heating element. In some embodiments, the infrared heating element is a second and / or a third temperature control element in addition to a first temperature control element. In some embodiments, the infrared heating element is positioned near a location along the path between a cooling element and a build platform and / or a light source along a conveying device (e.g., a carrier platform (such as a carrier film)). In some embodiments, the infrared heating element is configured to irradiate (i.e. heat) a portion of the resin as it is conveyed toward the build platform (as a non-limiting example, such as...). Figure 6(As shown). Therefore, in some embodiments, the infrared heating element is configured to heat a region (e.g., a surface) of the resin. In some embodiments, this region is heated to a temperature relatively higher than a portion of the resin outside this region. As a non-limiting example, a first surface of the resin can be heated to 20°C higher than a second surface of the resin (e.g., located on the opposite side of the resin). Local heating of the resin by, for example, an infrared heating element can improve the adhesion of the resin layer and also allow manipulation of the material properties of the cured material. In some embodiments, the infrared heating element is located above the carrier platform (e.g., above the carrier film). In some embodiments, the infrared heating element is located below the carrier platform (e.g., below the carrier film). In some embodiments, the infrared heating element is located above the build platform. In some embodiments, the infrared heating element is configured to heat a portion of the 3D printed object on the build platform (e.g., the surface of the 3D printed object can be heated before depositing the next layer of resin). In some embodiments, the infrared heating element is configured to emit microwave light.

[0098] In some embodiments, the infrared heating element is positioned such that it is configured to apply heat to at least one region of the resin before at least one region of the resin is cured. In some embodiments, the infrared heating element is positioned such that it is configured to apply heat to at least one region of the resin immediately before at least one region of the resin is cured (i.e., within 10 seconds, 5 seconds, or 1 second of polymerization). In some embodiments, the infrared heating element is an infrared laser. In some embodiments, the infrared heating element is an infrared lamp. In some embodiments, the infrared heating element is an infrared lamp with a digital mirror device. In some embodiments, the infrared heating element is a scanning infrared laser. In some embodiments, the infrared heating element is an infrared diode array. In some embodiments, the infrared heating element is another controllable infrared light source.

[0099] In some embodiments, the heating element includes a heating block that uses ultrasonic heating. In some embodiments, the heating element includes a heating block with limited pixel control and uses ultrasonic heating. In such embodiments, ultrasonic heating is intended to heat specific locations on the resin. In some embodiments, a heating element including a heating block that uses ultrasonic heating is used instead of an infrared heating element. In some embodiments, the adhesive enhancer includes a monomer that is highly exothermic when exposed to light.

[0100] In some embodiments of the systems disclosed herein, the system includes a particle applicator. In some embodiments, the particle applicator is positioned and configured to apply particles to the surface of the resin after the resin has been introduced by a resin injector and / or after the resin has passed through a thickness controller. In some embodiments, the particle applicator is positioned and configured to apply particles to the surface of the resin before the resin passes through a thickness controller and / or before the resin passes through a cooling element. As a non-limiting example, embodiments of the particle applicator in the systems disclosed herein... Figure 6 As shown in the figure. In some embodiments, the particle applicator is a funnel. In some embodiments, the particle applicator is a sprayer. In some embodiments, the particle applicator is an inkjet device that spatially controls where the applied particulate material is applied. In some embodiments, the particle applicator is a dispensing technique for spatially controlling the dispensing of particulate material.

[0101] In some embodiments, the particulate applicator is configured to apply an adhesion promoter to the resin (i.e., it is a device configured to apply an adhesion promoter). In other embodiments, the particulate applicator is configured to apply material to reduce adhesion and / or adjust the material properties of the resin and / or the cured polymer material formed therefrom. In some embodiments, the adhesion promoter comprises a powdered adhesion promoter. In some embodiments, the adhesion promoter comprises a liquid adhesion promoter. In some embodiments, the adhesion promoter comprises an infrared absorbing compound, carbon black, a dye, a multiphoton absorber, metal particles, nanoparticles, water absorbed into silica, or any combination thereof. In some embodiments, the adhesion promoter comprises an adhesive. In some embodiments, the adhesion promoter comprises a monomer system (e.g., an adhesive monomer system). In some embodiments, the particulate applicator is configured to apply an anti-adhesion agent to the resin. In some embodiments, the anti-adhesion agent prevents layers of resin from sticking together (e.g., when rolled or stacked). In some embodiments, the adhesion promoter is an anti-adhesion agent. In some embodiments, the material performs each function at different temperatures. Non-limiting examples of materials that act as both adhesive inhibitors and adhesive promoters may, for example, resist adhesion when cold and promote adhesion when hot (heated). In some embodiments, the material may be, for example, solid when cold and liquid when hot.

[0102] In some embodiments, the microparticle applicator is configured to apply a light absorber to the resin. In some embodiments, the microparticle applicator is configured to apply the light absorber and any of the aforementioned microparticles (e.g., adhesion promoters and / or adhesive monomers). In some embodiments, the light absorber is applied as a thin layer. In some embodiments (as a non-limiting example), when making an uncured resin sheet (e.g., as... Figure 9 (as shown) and / or when forming rolls of uncured resin (e.g., as shown) Figure 8As shown in the figure, at least one side of the uncured resin includes a light absorber. In some embodiments, both sides of the uncured resin include a light absorber. In some embodiments, the light absorber is applied as a film, for example, by using a microparticle applicator. In some embodiments, the light absorber is applied together with a binder enhancer and / or a binder monomer.

[0103] In some embodiments of the systems disclosed herein, the uncured and cooled resin includes at least one of an anti-adhesion agent, an adhesion promoter, and a light absorber applied to at least one side of the resin. In some embodiments, the uncured and cooled resin includes at least two of an anti-adhesion agent, an adhesion promoter, and a light absorber applied to at least one side of the resin. In some embodiments, the uncured and cooled resin includes an anti-adhesion agent and a light absorber applied to one side of the resin. In some embodiments, the uncured and cooled resin includes an adhesion promoter and a light absorber applied to one side of the resin.

[0104] In some embodiments of the systems disclosed herein, the uncured and cooled resin includes at least one of an anti-adhesion agent, an adhesion promoter, and a light absorber applied to at least both sides of the resin (e.g., on both sides, such as the top and bottom of a resin sheet). In some embodiments, the uncured and cooled resin includes at least two of an anti-adhesion agent, an adhesion promoter, and a light absorber applied to at least both sides of the resin. In some embodiments, the uncured and cooled resin includes an anti-adhesion agent and a light absorber applied to both sides of the resin. In some embodiments, the uncured and cooled resin includes an adhesion promoter and a light absorber applied to both sides of the resin.

[0105] In some embodiments of the systems disclosed herein, uncured and cooled resin is transported to a build platform and a light source, whereby a portion of the resin is cured to form a 3D printed object. In some embodiments, uncured resin remains (e.g., uncured resin portions during the production of the 3D printed object). In some embodiments of the systems disclosed herein, unused and uncured resin is recycled or reused. In some embodiments of the systems disclosed herein, unused and uncured resin is recycled for forming, for example, another layer of resin material or for producing another printed 3D object. In some embodiments, a carrier platform (e.g., a carrier film) is configured to transport uncured resin from the build platform toward a resin injector. Figure 5A non-limiting example of a system including a carrier membrane configured to transport uncured resin from a build platform toward a resin injector is shown. In some embodiments, the carrier platform (e.g., the carrier membrane) is configured to transport the uncured resin from the build platform to a remelter, and from the remelter to the resin injector. The remelter is configured to apply heat to the uncured resin to form a heated resin. In some embodiments, the resulting heated resin is substantially similar to the resin introduced by the resin injector and / or the resin heated by a first heating element, and is therefore incorporated into the system in the same manner (i.e., recycled). In some embodiments, unused resin is automatically recycled or recycled during an automated process (e.g., as...). Figure 5 and Figure 6 (As shown). In some embodiments, automated recycling means that unused resin does not need to be treated before its reuse in the process or system. As a non-limiting example, such as Figure 5-6 As shown, unused resin is automatically conveyed through the system to be reused during the formation of another layer of resin (i.e., it is an automated process).

[0106] In some embodiments of the systems disclosed herein, the carrier platform (e.g., a carrier membrane) is configured to move along a horizontal plane. In some embodiments, the construction platform is configured to move along a vertical plane. In some embodiments, the carrier platform is configured to move along a horizontal plane and the construction platform is configured to move along a vertical plane. As a non-limiting example, Figure 7 The illustration shows a carrier platform configured to move along a horizontal plane (e.g., when approaching a build platform) and a build platform configured to move along a vertical plane (e.g., for depositing resin onto the build platform or otherwise depositing resin onto one or more layers of resin material already deposited onto the build platform during the formation of a 3D printed object). In some embodiments, the carrier platform is configured to move along a vertical plane. In some embodiments, the carrier platform is configured to move vertically (e.g., along a vertical plane) as it approaches the build platform (e.g., in some embodiments, the build platform is configured to remain stationary while a system including the carrier platform (e.g., a carrier film) is configured to move vertically toward the build platform to deposit resin).

[0107] In some embodiments of the system disclosed herein, the system includes a first feed roll (e.g., a carrier film feed roll). In some embodiments, the first feed roll is configured to deliver a carrier platform without resin. In some embodiments, the system also includes a first reel. In some embodiments, the first reel is configured to receive a carrier platform carrying uncured resin. In some embodiments, the system includes a first feed roll and a first reel, the first feed roll being configured to deliver a carrier platform without resin, and the first reel being configured to receive a carrier platform carrying uncured resin. As a non-limiting example, Figure 8 An embodiment is shown in which a first feed reel is configured to apply a carrier platform without resin and a first reel is configured to receive a carrier platform carrying uncured resin. In some embodiments, the first reel is configured to receive a carrier platform carrying uncured resin and form a roll comprising a carrier platform (e.g., a carrier film) and resin (e.g., a...). Figure 8 Volume (430) is shown.

[0108] In some embodiments, the resin injector and the first temperature control device are located between the first feed roll and the first reel. In some embodiments, the first cooling device is located between the first feed roll and the first reel. In some embodiments, the first heating device is located between the first feed roll and the first reel. In some embodiments, the second temperature control device, the microparticle applicator, the layer thickness controller, or any combination thereof are located between the first feed roll and the first reel.

[0109] In some embodiments of the system disclosed herein, the system includes a second feed roll and a second reel. In some embodiments, the second feed roll is a roll formed from a first reel. As a non-limiting example, Figure 8 A first reel is shown, configured to receive a carrier platform carrying uncured resin to form a roll (430), and this roll (430) is used as a second feed roll (i.e., at 405). In some embodiments, the first process (e.g., forming a roll using the first reel, such as...) Figure 8 The resin forming step (401) shown) and the second process (e.g., applying the roll, such as Figure 8 The printing step (405) shown is configured to be separable. In some embodiments, the first and second processes can be configured to be separated by a distance (e.g., each process can occur in separate locations or facilities). In some embodiments, the first and second processes can be configured to be separated in time (e.g., the roll can be formed before it is used in the second stage). Advantageously, the roll (e.g., comprising resin and carrier platform) can be configured to be transportable (e.g., transported to the manufacturing site) or can be configured to be stored until ready for use.

[0110] In some embodiments of the systems disclosed herein, such as those including a second feed roll and a second reel, the build platform is configured to receive resin from a carrier platform (e.g., a carrier film). In some embodiments, the light source and the build platform are located between the second feed roll and the second reel. As a non-limiting example, Figure 8 The second stage (405) illustrates a configuration where the light source and build platform are located between the second feed roll and the second reel. In some embodiments of the system described herein, the system also includes a window located between the light source and the build platform. In some embodiments, the system further includes an infrared heating element located between the second feed roll and the second reel. The use of the infrared heating element to, for example, heat areas and / or surfaces of resin and / or 3D printed objects is also described herein.

[0111] In some embodiments of the system disclosed herein, the system further includes a cutting device. In some embodiments, the cutting device includes a molding cutter, a laser cutter, a blade, or other cutting device or another cutting mechanism. In some embodiments, the cutting device is a molding cutter, a laser cutter, or a blade. In some embodiments, the cutting device is configured to cut uncured resin into multiple uncured resin sheets. As a non-limiting example, Figure 9 A cutting device (e.g., cutting device (510)) configured to cut uncured resin into uncured resin sheets (e.g., sheets (520)) is shown. In some embodiments, the system further includes a robotic arm configured to move at least some of the plurality of uncured resin sheets. In some embodiments, the robotic arm is configured to move at least some of the plurality of uncured resin sheets to a build platform. In some embodiments, the system further includes a storage device configured to store the plurality of uncured resin sheets. In some embodiments, the plurality of uncured resin sheets are stored in a cassette. In some embodiments, the plurality of uncured resin sheets are stored in a stack.

[0112] In some embodiments of the system disclosed herein, the system further includes a mask. In some embodiments, the mask is placed between a light source and a carrier platform (e.g., a carrier film). In some embodiments, the mask is placed between a light source and a resin. In some embodiments, the mask is configured to provide patterned exposure to the resin.

[0113] In some embodiments of the systems disclosed herein, resin is cured (e.g., photopolymerized) to form a 3D-printed object. The 3D-printed object comprises a polymeric material formed from the resin. In some embodiments, the 3D-printed object (also referred to herein as a “printed object” or “object”) is an orthodontic appliance. In some embodiments, the orthodontic appliance is an aligner, expander, or spacer. In some embodiments, the orthodontic appliance includes a plurality of tooth-receiving cavities configured to reposition teeth from a first form to a second form. In some embodiments, the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial form to a target form. In some embodiments, the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial form to a target form according to a treatment plan. In some embodiments, the orthodontic appliance is an aligner.

[0114] This document provides exemplary processes and systems related to this disclosure. Those skilled in the art will understand that these embodiments are non-limiting and that they are characterized as composable, alternative, and / or separable. As a non-limiting example, and as further described below, although... Figure 6 An embodiment is shown including a device (190) configured to apply additional components to a resin and an infrared heater (155), but those skilled in the art will understand that in some cases a system may be used that applies only one of the two elements. As another non-limiting example, although... Figure 8 An embodiment without, for example, an infrared heater (155) is shown, but those skilled in the art will understand that devices employing such elements may be used in some cases. As another non-limiting example, although... Figure 8 An embodiment in which the construction platform (140) moves vertically is shown, but those skilled in the art will understand that horizontal movement, or a combination of horizontal and vertical movement, may be used in some cases.

[0115] Therefore, those skilled in the art will understand that there are various ways in which aspects and features of the disclosure and embodiments herein can be combined, and that these ways are not limited to the exemplary embodiments provided herein.

[0116] A recycling process and system with automated resin reuse

[0117] In some embodiments of the process disclosed herein, the resin is heated and formed to produce a thin layer (e.g., as a film). The film is cooled to a desired temperature at a desired rate, thereby controlling the material properties within the resin or the material obtained by curing the resin. The cooled film is transported to a build platform and deposited on the build platform, and then exposed to light (e.g., photopolymerization). In some embodiments, specific areas of the resin are exposed to light (e.g., by using a mask), so that the resin layer includes cured and uncured areas. In some embodiments, the uncured resin is removed, leaving only one or more of the exposed areas (e.g., a 3D object formed from the polymerized material). This process is repeated until all layers of the 3D object are produced and the 3D object is formed. Residual uncured resin adhering to the object can be removed, for example, by heating the object to a temperature above the melting point of the uncured resin but below the melting temperature of the cured resin, and / or by cleaning the 3D object with a solvent (e.g., dissolving the uncured resin while the cured material remains intact). In some embodiments, the object is post-processed (e.g., by cleaning). In some embodiments, the 3D object is post-cured using light and / or heat.

[0118] In some embodiments described herein, the 3D object (e.g., a 3D printed object) is configured to stand on its own when it is built. For example, in embodiments described herein, uncured resin remains attached to, for example, a carrier platform (e.g., a carrier film), the object has high green strength, and the resin is supported by the carrier platform until it is cured. Therefore, in some embodiments, the processes and methods described herein require fewer support structures than typical support structures, or no support structures at all, during the formation of the 3D object.

[0119] Figure 5 An embodiment of the system and first process described herein is illustrated. A printer (101) is equipped with a resin injector (105) that introduces resin (120) into the printer. In some embodiments, the resin injector introduces resin into the printer in a heated state, becoming thermal resin (122). The printer (101) includes a carrier film (130). The resin injector (105) introduces resin (120) or thermal resin (122) into the printer by applying material to the carrier film (130). In some embodiments, the printer (101) includes a heating plate (111) for heating the introduced resin (120) to a heated state or maintaining the heated state of the thermal resin (122).

[0120] In some embodiments, the printer (101) includes a layer thickness controller (115). In some embodiments, the layer thickness controller (115) is a scraper. The layer thickness controller (115) is a means for controlling the thickness of resin (120) or hot resin (122) on a carrier film (130). The carrier film (130) transports resin material through the printer (101). The hot resin (122) is transported to proximity to a cooling plate (135), which is configured to cool the temperature of the hot resin (122) to cold resin (124). In some embodiments, the cooling plate (135) is connected to a cooler, a thermoelectric cooler, or another cooling mechanism.

[0121] Cooled resin (124) is transported to a build platform (140). The cooled resin (124) is deposited on the build platform (140) and exposed to light from a light source (151), thereby curing the resin. Layers of cooled resin (124) are continuously deposited and cured by exposure to light from the light source (151). In this manner, a printable object (161) comprising multiple cured polymer layers is formed. The printer (101) also includes means for moving (171) the build platform relative to a unit comprising a carrier film. In some embodiments, the movement (171) is horizontal or substantially similar to the movement of an adjacent carrier film (130). In some embodiments, the movement (171) of the build platform (140) is matched to the rate of movement of the carrier film (130) such that each layer of cooled resin (124) is sequentially deposited onto the build platform (140) and / or the printable object (161).

[0122] In some embodiments, after the curing of the adjacent cooled resin (124), the uncured resin (126) remains adhered to the carrier film (130). The cooled uncured resin (126) remains on the carrier film (130), while the photocured resin remains on the printed object (161). The uncured resin (126) can be recycled. In some embodiments, the uncured resin (126) is transported to the vicinity of a remelter (180) configured to heat the uncured resin (126) and prepare it for mixing with the introduced resin (120). In some embodiments, the remelter (180) includes a heating plate. In some embodiments, the remelter (180) includes an infrared emitter configured to heat the uncured resin (126) for example from above by exposing it to infrared light. The reheated resin (128) is transported to a resin injector (105), which introduces new resin (120) (e.g., heated resin (122)) into the carrier film (130) to replace the amount of resin lost during printing of the printed object (161). In some embodiments, the remelter includes a heating plate. In some embodiments, the reheated resin is mixed at the scraper due to the movement of the carrier film.

[0123] Turn Figure 6 In some embodiments, the printer (101) includes a device (190) configured to apply additional components (e.g., solid particles or liquid aerosols) to the resin. In some embodiments, the device (190) is configured to apply an adhesion promoter (195). In some embodiments, the device (190) is a funnel or a sprayer. In some embodiments, the adhesion promoter (195) promotes adhesion of resin layers in the printed object (161). In some embodiments, the adhesion promoter is a liquid adhesion promoter. In some embodiments, the adhesion promoter is a powdered adhesion promoter. The adhesion promoter (195) is dispersed onto the surface of the heated resin (122). In some embodiments, the adhesion promoter and / or other additives are added to the resin while the resin is at least partially cooled. In some embodiments, the adhesion promoter and / or other additives are added to the resin while the resin is completely cooled.

[0124] In some embodiments, the printer (101) further includes an infrared heater (155) configured to heat the surface of the cold resin (124). In some embodiments, heating the surface of the cold resin (124) promotes layer-to-layer adhesion during the construction of the printed object (161). For example, in Figure 6In this embodiment, an infrared heater (155) is shown located at the bottom of the cold resin (124) (e.g., configured to heat the surface of the cold resin that will come into contact with the build platform (140) or the printable object (161). In some embodiments, the printer (101) includes an infrared heater (155) configured to irradiate and heat the top of the printable object (161) to which the cold resin (124) is applied (e.g., the infrared heater (155) may be located above the printable object (161)).

[0125] Resin-supported cyclic processes and systems

[0126] In some embodiments of the process disclosed herein, the resin is heated and formed to produce a thin layer (e.g., as a film). The film is cooled to a desired temperature at a desired rate, thereby controlling the material properties within the resin or the material obtained by curing the resin. The cooled film is transported to a build platform and deposited on the build platform, and then exposed to light (e.g., photopolymerization). In some embodiments, specific areas of the resin are exposed to light (e.g., by using a mask), so that the resin layer includes cured and uncured areas. In some embodiments, a portion of the uncured resin is retained along with one or more exposed areas (e.g., a 3D object formed from the polymerized material), and one or more additional layers of uncured resin are added thereon. This process is repeated until all layers of the 3D object are produced and the 3D object is formed. In some embodiments, the formed 3D object is substantially surrounded, wrapped, or enclosed by uncured resin (e.g., it may include multiple layers, wherein each resin sheet includes a portion of the 3D object surrounded by uncured resin). In some embodiments, when the 3D object has been formed, residual uncured resin adhering to the object can be removed, for example, by heating the object to a temperature above the melting point of the uncured resin but below the melting temperature of the cured resin, and / or by cleaning the 3D object with a solvent (e.g., dissolving the uncured resin while the cured material remains intact). In some embodiments, the object is post-processed (e.g., by cleaning). In some embodiments, the 3D object is post-cured using light and / or heat.

[0127] In some embodiments described herein, a solid material block comprising both cured polymeric material (e.g., photopolymer resin) and uncured resin is constructed along with the 3D object. In some embodiments, it is preferred that such a solid material block is formed during a period of time when the resin layer is deposited onto the build platform or onto a previous resin layer applied to the build platform, and when the resin is semi-solid, substantially solid, or solid. In some embodiments, no support structure is required on the build platform; for example, the uncured resin in the solid block, as described herein, can be used to support the 3D object, thus additional support structures on the build platform are not necessary. The uncured resin can then be collected from the 3D object after its formation (e.g., by melting or cleaning with a solvent, as further described herein) to be recycled back to a heating element that melts the resin for injection into the printer.

[0128] Figure 7 Embodiments of the system and second process described herein are illustrated. In some embodiments, a printer (101) is configured to deposit cold resin (124) onto a build platform (140) or a printed object (161) as deposited uncured resin (165). The deposited uncured resin (165) and the cured printed object (161) are deposited sequentially in layers. The printer (101) also includes means for moving (171) the build platform relative to a unit comprising a carrier film. In some embodiments, the movement (171) is vertical, or substantially perpendicular to the proximal carrier film (130). In some embodiments, the movement (171) is a movement of the build platform (140). In some embodiments, the movement (171) is a movement of the carrier film unit. No support structure is required for the 3D printed object (161), and therefore in some embodiments, the build platform (140) has no support elements. The deposited uncured resin (165) can serve to support the printed object (161). The deposited uncured resin (165) can be recycled. As a non-limiting example, after the construction of the printed object is completed, the deposited uncured resin (165) can be removed from the 3D printed object (161), and the deposited uncured resin (165) can be reheated and deposited into the printer (101) via a resin injector (105). In some embodiments, the printer (101) includes a remelter (180), which can be activated if needed (e.g., for removing or heating residual uncured resin adhering to the carrier film (130)).

[0129] Processes and systems with resin forming and printing steps

[0130] In some embodiments of the process disclosed herein, the process comprises two distinct stages that may be separated by distance and / or time. In some embodiments, the resin is heated and formed to produce a thin layer (e.g., as a film). The film is cooled to a desired temperature at a desired rate, thereby controlling the material properties within the resin or the material obtained by curing the resin. In some embodiments, the resin layer may be configured to be stored, transported, or otherwise used in a separate step (e.g., by rolling up the resin using a carrier platform, or by cutting the resin layer into separate segments). The cooled film is transported to a build platform and deposited on the build platform, and then exposed to light (e.g., photopolymerization). In some embodiments, specific areas of the resin are exposed to light (e.g., by using a mask), so that the resin layer comprises cured and uncured areas. In some embodiments, the uncured resin is removed, leaving only the exposed areas (e.g., a 3D object formed from the polymerized material). In some embodiments, the uncured resin is retained along with the cured resin layer. This process is repeated until all layers of the 3D object are produced and the 3D object is formed. Residual uncured resin adhering to the object can be removed, for example, by heating the object to a temperature above the melting point of the uncured resin but below the melting temperature of the cured resin, and / or by cleaning the 3D object with a solvent (e.g., dissolving the uncured resin while the cured material remains intact). In some embodiments, the object is post-processed (e.g., by cleaning). In some embodiments, the 3D object is post-cured using light and / or heat.

[0131] In some embodiments, forming a layer of uncured resin includes extruding uncured resin. In some embodiments, forming a layer of uncured resin includes casting uncured resin. In some embodiments, the uncured resin is cooled to a solid or substantially solid form and cut into multiple segments. In some embodiments, the multiple segments are configured to form a 3D printed object. In some embodiments, a pick-and-place robot is used to place the individual segments onto a build platform.

[0132] Figure 8An embodiment of the system and third process described herein is illustrated. Similar to the second process described above, a solid block of material (e.g., deposited uncured resin (165) and cured resin to form the printed object (161)) is constructed during the construction of the 3D printed object (161). In some embodiments, during the formation of the 3D printed object (161), a roll (430) of uncured cooled resin (124) and a carrier film (130) is formed in a first stage (401), and then the roll (430) is used in a second stage (405). The first process (401) and the second process (405) may be separated by a distance (e.g., each process may be performed at separate locations or facilities) and / or may be separated in time (e.g., the roll (430) may be formed before its use in the second stage). In this way, the solid resin (e.g., the solid resin on the roll (430)) may be transportable (e.g., transported to the manufacturing location) or stored until ready for use.

[0133] In the first stage (401), uncured resin is bonded to a carrier film (130), and in the second stage (405), a 3D printed object (161) is manufactured. Similar to the first process, the third process utilizes the carrier film (130) to deliver resin material. The carrier film (130) is supplied by a carrier film feed roll (411). The first stage (401) includes a resin injector (105) that introduces resin (120) into the printer. In some embodiments, the resin injector introduces resin into the heated carrier film (130) to become thermal resin (122). In some embodiments, the first stage (401) includes a heating plate (111) to heat the introduced resin (120) to a heated state or to maintain the heated state of the thermal resin (122).

[0134] In some embodiments, the first stage (401) includes a layer thickness controller (115). In some embodiments, the layer thickness controller (115) is a scraper. The layer thickness controller (115) is a means for controlling the thickness of the resin (120) or hot resin (122) on the carrier film (130). In some embodiments, the hot resin (122) is transported to the vicinity of a cooling plate (135) configured to cool the temperature of the hot resin (122) to cold resin (124). In some embodiments, the cooling plate (135) is connected to a cooler, a thermoelectric cooler, or another cooling mechanism. In some embodiments, the hot resin (122) is transported to the vicinity of a fan, a water bath, or another cooling mechanism configured to cool the temperature of the hot resin (122) to cold resin (124). The cooled resin (124) is wound up by a reel (420) to form a roll (430) of uncured resin and carrier film.

[0135] In some embodiments, the first stage (401) includes a device (190) configured to apply an adhesive enhancer (195). In some embodiments, the device (190) configured to apply the adhesive enhancer (195) is a funnel or a sprayer. In some embodiments, the adhesive enhancer (195) promotes adhesion of resin layers in the printed object (161). In some embodiments, the adhesive enhancer is a liquid adhesive enhancer. In some embodiments, the adhesive enhancer is a powdered adhesive enhancer. In some embodiments, the device (190) configured to apply the adhesive enhancer is also configured to apply a material to prevent two resin layers from sticking together on the roll. In some embodiments, the adhesive enhancer (195) prevents the resin from sticking together on the roll. The adhesive enhancer (195) is dispersed onto the surface of hot resin (122) or cooled resin.

[0136] In the second stage (405), the roll (430) of uncured resin and carrier film is unrolled and the carrier film (130) is transported toward the reel (450) towards the roll. Cooled resin (124) is transported to the build platform (140). The cooled resin (124) is deposited on the build platform (140) and exposed to light from the light source (151), thereby curing the resin. Optionally, the second stage includes a window (440) between the light source (151) and the carrier film (130). Layers of cooled resin (124) are continuously deposited and cured by exposure to light from the light source (151). In this way, a printed object (161) comprising multiple cured polymer layers is formed. Deposited uncured resin (165) and cured printed object (161) are continuously deposited in layers. The second stage (405) also includes means for moving (171) the build platform relative to the unit including the carrier film. In some embodiments, the movement (171) is vertical, or substantially perpendicular to, the movement of the proximal carrier membrane (130). In some embodiments, the movement (171) is the movement of the build platform (140). In some embodiments, the movement (171) is the movement of the carrier membrane unit. No support structure is required for the 3D printed object (161), therefore in some embodiments, the build platform (140) has no support elements. The deposited uncured resin (165) can serve to support the printed object (161). The deposited uncured resin (165) can be recycled. As a non-limiting example, after the construction of the printed object is completed, the deposited uncured resin (165) can be removed from the 3D printed object (161), and the deposited uncured resin (165) can be reheated and deposited into the first stage (401) via a resin injector (105). In some embodiments, the take-up reel (450) includes unused cooled resin (124).

[0137] Figure 9An embodiment of a third process including a cutting device (510) is shown. Figure 9 The first phase (500) is basically similar to Figure 8 The first stage (401) shown is modified as necessary. In some embodiments, for example... Figure 9 In the illustrated embodiment, the first stage (500) includes a cutting device (510) that cuts portions of the cooled resin (124). The cutting device (510) may be a die-cutting machine, a laser cutter, a blade, or any other cutting device or mechanism. The cut fragments of solid resin (520) are collected and fed to subsequent process steps.

[0138] In some embodiments, the individual segments of solid resin (520) are collected by a robotic arm. In some embodiments, the individual segments of solid resin (520) are sorted by stacking. In some embodiments, the stacked individual segments of solid resin (520) include a release liner (e.g., a release layer) between the segments of solid resin (520) to prevent the layers from sticking together. In some embodiments, an adhesive enhancer (195) also prevents the segments of solid resin (520) from sticking together, for example, when stacked (e.g., by using an adhesive enhancer in powder form). In some embodiments, the segments (520) of solid resin are sorted by placing them in a box.

[0139] During the formation of the 3D printed object (161), a fragment (520) of solid resin is formed in a first stage (500), and then said fragment (520) is used in a second stage (505). The first process (500) and the second process (505) may be separated by a distance (e.g., each process may be carried out at separate locations or facilities) and / or may be separated in time (e.g., the fragment (520) of solid resin may be formed before it is used in the second stage). In this way, the fragment (520) of solid resin may be transportable (e.g., transported to the manufacturing site) or stored until ready for use.

[0140] Multiple solid resin segments (520) are formed, for example, in a stack or cassette, from segments (520) of solid resin formed in the first stage. In some embodiments, an adhesive enhancer is applied between the segments of solid resin or to the segments of solid resin after the segments of solid resin are placed onto the build platform (140) or the printed object (161). In the second stage (505), uncured solid resin segments (520) are placed on the build platform (140) or subsequently layered, building on top of previous resin layers (e.g., the 3D printed object (161) and deposited uncured resin (165)). In some embodiments, a pick-and-place robotic arm (530) is configured to place the solid resin segments (520) on the build platform (140) or on top of previous resin layers (e.g., the 3D printed object (161) and deposited uncured resin (165)).

[0141] In an embodiment of the second stage (505), a solid resin segment (520) is exposed to light from a light source (151) to cure the resin. Optionally, the second stage includes a window (440) between the light source (151) and the solid resin segment (520). In some embodiments, a window is not required (e.g., if the solid resin segment is flat and the layers have high adhesion). Layers of the cooled solid resin segment (520) are deposited sequentially and cured by exposure to light from the light source (151). In this way, a printed object (161) comprising multiple cured polymer layers is formed. Deposited uncured resin (165) is deposited sequentially layer by layer with the cured printed object (161). The second stage (405) also includes means for moving (171) the build platform relative to the unit comprising the carrier film. In some embodiments, the movement (171) is vertical. In some embodiments, the movement (171) is a movement of the build platform (140). No support structure is required for the 3D printed object (161), therefore in some embodiments, the build platform (140) has no support elements. The deposited uncured resin (165) can serve to support the printed object (161). The deposited uncured resin (165) can be recycled. As a non-limiting example, after the construction of the printed object is completed, the deposited uncured resin (165) can be removed from the 3D printed object (161), and the deposited uncured resin (165) can be reheated and deposited into the first stage (500) via a resin injector (105).

[0142] In some embodiments, the surfaces of the solid resin fragment (520) and / or the surface of the 3D printed object (161) are heated (e.g., by applying infrared light or exposing it to heating elements, such as those further described herein) to improve the adhesion of the resin layer. In some embodiments, the adhesion of the layer is improved by applying an adhesive. In some embodiments, the solid resin fragment (520) has a low melting temperature. In some embodiments, this low melting temperature is low relative to the ambient air temperature. In some embodiments, the solid resin fragment (520) has a low melting temperature such that the pressure applied to the resin during the movement (171) of the build platform (140) (e.g., pressure from a window (440) pressed against the solid resin fragment (520)) partially melts the resin and thus adheres to the previously deposited layer before exposure to light.

[0143] Processes and systems with printheads

[0144] In some embodiments of the systems and processes described herein, during the formation of a 3D object, heated resin is applied as a layer directly to the surface of a build platform, or otherwise applied over a layer of resin previously applied to the build platform. For example, in some embodiments, heated resin is applied directly to the build platform and / or applied over a previous layer of the build platform by extrusion or by a melting and leveling mechanism. In some embodiments, the resin layer is cooled to a desired temperature at a desired rate. In some embodiments, the resin is then exposed to light in selected areas to form cured areas of the resin (e.g., photopolymer material of the 3D object) and uncured areas. As further described herein, in some embodiments, uncured resin is removed by applying heat, solvents, centrifugation, ultrasonic baths, or other methods for removing said uncured resin as all layers of the object are formed.

[0145] In some embodiments, the uncured resin supports the 3D object, thus eliminating the need for additional support structures from the build platform. In some embodiments, interlayer adhesion between resin layers is enhanced because molten or otherwise heated resin is applied directly to previous resin layers. In some embodiments, resin cooling may occur directly on the solid block of material formed (e.g., the 3D printed object and previous layers of uncured resin) or otherwise directly on the build platform. In some embodiments, thin layers of resin are cooled with each layer deposition. In some embodiments, the applied resin layers are configured for rapid cooling, for example, by applying the resin layers as thin layers. In some embodiments, the thin layers of resin cool in less than 60 seconds, less than 30 seconds, less than 20 seconds, less than 10 seconds, or less than 5 seconds.

[0146] In some embodiments, this disclosure provides a system for forming objects, the system comprising:

[0147] The printhead includes:

[0148] A resin injector, configured to dispense resin;

[0149] The first temperature control element; and

[0150] Light source; and

[0151] The platform is built and configured to retain objects.

[0152] As further described herein, in some embodiments, the printhead is configured to apply resin to a build platform to form a deposited layer. In some embodiments, the printhead is also configured to apply resin onto the deposited layer to form repeatedly stacked layers of material. In some embodiments, the resin is exposed to a light source before, during, or after each deposited resin layer is applied to the build platform or a previous deposited layer. In some embodiments, the heating element provides spatial control of the light energy by controlling the light intensity and / or controlling the dose.

[0153] In some embodiments, the printhead includes more than one resin injector (i.e., multiple resin injectors). In some embodiments, each of the multiple resin injectors is configured to dispense individual and / or different resins. As a non-limiting example, a printhead including three resin injectors can be configured to dispense three different resins.

[0154] In some embodiments, the printhead further includes an infrared heating element. This infrared heating element heats the applied resin by exposing it to infrared light. In this way, the properties of the applied resin and the properties of the polymer material formed therefrom can be adjusted. In some embodiments, the infrared heating element is positioned such that it is configured to apply heat to at least one region of the resin before that region is cured. In some embodiments, the infrared heating element is positioned such that it is configured to apply heat to at least one region of the resin immediately before that region is cured (i.e., within 10 seconds, 5 seconds, or 1 second of polymerization). In some embodiments, the infrared heating element is an infrared laser. In some embodiments, the infrared heating element is an infrared lamp. In some embodiments, the infrared heating element is an infrared lamp with a digital mirror device. In some embodiments, the infrared heating element is a scanning infrared laser. In some embodiments, the infrared heating element is an infrared diode array. In some embodiments, the infrared heating element is another controllable infrared light source.

[0155] In some embodiments, the system includes a printhead configured to move horizontally. In some embodiments, the printhead is configured to move horizontally in a two-dimensional plane. For example, the printhead may be configured to move in the X and Y planes while the build platform is below it (along the Z-axis). In some embodiments, the printhead is configured to move vertically. In other embodiments, the printhead is configured to move spatially in three dimensions. In some embodiments, the system includes a build platform configured to move horizontally. In some embodiments, the build platform is configured to move horizontally in a two-dimensional plane. For example, the build platform may be configured to move in the X and Y planes while the printhead is above it (along the Z-axis). In some embodiments, the build platform is configured to move vertically. In other embodiments, the build platform is configured to move spatially in three dimensions.

[0156] Figure 10 An embodiment of the system and the fourth process described herein is shown. In the third process (e.g., Figure 10 The system 600 shown herein has a printhead (601) for building a 3D printed object (161) without using a carrier film or support structure at the build platform. Unused resin can be recycled, and this embodiment can be configured to produce individual layers comprising more than one material (i.e., forming a single layer of multiple materials). The printhead (601) includes an extruder (610) and a light source (151). In some embodiments, the printhead (601) includes a heater (630). In some embodiments, the printhead includes a cooler (620). In some embodiments, the extruder (610) is configured to extrude a film. In some embodiments described herein, an extruded film is produced. In some embodiments, a die extruded film is produced.

[0157] like Figure 10 As shown, the printhead (601) is configured to extrude hot, molten resin (122) from the extruder (610) (e.g., to...). Figures 5 to 9 The hot resin (122) is extruded by a medium resin injector (105) in a similar manner. In the embodiments described herein, the hot molten resin (122) is a photopolymerizable resin. In some embodiments, the printhead (601) includes a plurality of extruders (610). In some embodiments, the plurality of extruders are configured to allow multiple materials to be deposited (e.g., at least two extruders extruding different materials).

[0158] In the embodiments described herein, the extruded resin is applied directly to the build platform (140) for the first layer, and for all other layers, the extruded resin is subsequently applied on top of the previous layers (i.e., 2-n). For example, a second layer is built on top of a first layer, a third layer is built on top of a second layer, another layer is built on top of a third layer, and so on. In some embodiments, this disclosure provides multilayer films formed using a solid-state printer. In some embodiments, this disclosure provides films comprising more than one type of material (e.g., layers having a size of less than or equal to 100 micrometers). As a non-limiting example, a material film can be formed comprising a first layer of a first material, a second layer of a first material, and a second material disposed between the first and second layers of the first material. After exposure to a light source to photopolymerize these layers and bond them together, the object further described herein is thus formed. The thermoplastic layers and uncured resin can be removed (e.g., melted or dissolved). Thus, the object can be built layer by layer, each layer having a separate process depending on the material layer.

[0159] like Figure 10 As shown, in some embodiments, a cooler (620) is used to cool the applied hot resin (122). In some embodiments, cooling the resin with a cooler (620) forms a cooled resin (124) that has different material properties when cured (compared to the material properties of the hot resin when cured). In some embodiments, the cooler (620) is used to form a phase-separated material. In some embodiments, the cooler (620) is cooled air, cooled inert gas, or a rapidly evaporating and cooling jet liquid (e.g., butane, liquid nitrogen, or CO2 snow). In some embodiments, the cooler (620) may be in contact with a cooling roller. In some embodiments, the cooler (620) is a cooling plate (135).

[0160] In some embodiments, the printhead (601) includes a heater (630). In some embodiments, the resin is heated by the heater (630) before being exposed to a light source (151). In some embodiments, the heater (630) is an infrared heater configured to heat the resin by applying infrared irradiation. In some embodiments, heating the resin with the heater (630) alters the properties of the resin and the resulting photopolymer material.

[0161] The extruded resin is photopolymerized by exposure to a light source (151). In some embodiments, the exposure of the resin to the light source (151) described herein includes digital light processing (DLP). In some embodiments, the exposure of the resin to the light source (151) described herein includes stereolithography (SLA).

[0162] In the fourth process, resin layers (e.g., cooled resin 124) are continuously deposited and cured by exposure to light from a light source (151). In this manner, a printed object (161) comprising multiple cured polymer layers is formed. Deposited uncured resin (165) is continuously deposited layer by layer with the cured printed object (161). The deposited uncured resin (165) can be recycled. As a non-limiting example, after the construction of the printed object is completed, the deposited uncured resin (165) can be removed from the 3D printed object (161), and the deposited uncured resin (165) can be reheated and deposited into an extruder (610).

[0163] like Figure 10 As shown, in some embodiments, the system (600) further includes means for vertically moving (171) the build platform (140) relative to the printhead (601). In some embodiments, the movement (171) is a movement of the build platform (140). In some embodiments, the movement (171) is a movement of the printhead (601). In some embodiments, the system (600) further includes means for horizontally moving (640) the printhead (601) relative to the build platform (140). In some embodiments, the movement (640) is a movement of the build platform. In this way, the printhead (601) and / or the build platform (140) can be configured to move vertically (up and down) while the build platform moves horizontally (e.g., left and right and / or back and forth). In some embodiments described herein, the printhead (601), the build platform (640), or any combination thereof can move in one spatial direction, two spatial directions (e.g., planar movement), or three spatial directions.

[0164] Advantageously, as described above and utilizing the processes and methods disclosed herein, in some embodiments, the uncured resin is reduced and reused (e.g., recycled and redeposited into a thermal resin material). Some embodiments of the processes and methods described herein are compatible with stand-alone machines configured to be small and fast. For example, the processes and methods described herein can be used in a physician's office or other clinical settings to produce 3D objects (e.g., parts) that can be handled immediately after printing. In some embodiments, such printed objects do not have uncured resin removed (e.g., where the uncured resin is bio-inert or otherwise harmless to the user).

[0165] Methods for forming multiphase materials

[0166] This disclosure provides methods for forming cured polymeric materials (e.g., 3D printed objects). Advantageously, the photocurable resin (e.g., a resin photocured under cooling or other temperature-controlled conditions) described and processed herein can undergo physical changes capable of forming a two- or more-phase system. For example, physical changes (e.g., increased viscosity, curing, phase separation, or crystallization) may occur when the resin is cooled. In many embodiments, the changes associated with cooling of the material involve the formation of two or more phases in the system, and in some embodiments, these phases are maintained during the photopolymerization process of forming the 3D object. Thus, in some embodiments, the photocured 3D object is composed of a material having at least two phases. In some embodiments, the photocured 3D object comprises two, three, four, five, or more than five phases. In some embodiments, the size of the phase domains is controlled by one or more of temperature, temperature cooling rate, material additives (e.g., resin additives as further described herein), resin layer thickness, or other variables. In some embodiments, the multiphase 3D object formed by the processes and systems described herein has enhanced composite-like properties (e.g., by controlling the number of phases and / or the presence of multiple phases).

[0167] In some embodiments, this disclosure provides a method for forming a cured polymer material using a system as described herein. In some embodiments, this disclosure provides a method for forming a cured polymer material, the method including using the system described herein. In some embodiments, this disclosure provides a method for forming a cured polymer material, the method including:

[0168] Heating the resin;

[0169] The resin is applied to a carrier platform (e.g., a carrier membrane);

[0170] The temperature of the applied resin is adjusted using the first temperature control element;

[0171] Apply resin to the receiving component; and

[0172] At least a portion of the resin is cured to form a cured polymer material.

[0173] In some embodiments, the resin is heated to a flowable temperature. In some embodiments, the resin is heated to a flowable temperature and deposited onto a carrier platform using a resin injector as further described herein. In some embodiments, the resin injector includes an additional temperature control element (e.g., a heating element). In some embodiments, the resin injector is configured to heat the resin to a flowable temperature and deposit the flowable resin onto a carrier platform (e.g., a carrier film). In some embodiments, applying resin to the carrier platform includes applying resin to the carrier platform using a resin injector.

[0174] In some embodiments, adjusting the temperature of the applied resin using a first temperature control element includes cooling the resin. The first temperature control element is further described herein. In some embodiments, the first temperature control element is a first cooling element (e.g., when a resin injector applies hot resin to a carrier platform). In some embodiments, the first temperature control element is a first heating element (e.g., when a resin injector applies resin to a carrier platform, wherein the resin is not hot).

[0175] In some embodiments, the receiving component is a build platform. In some embodiments, the receiving component is a resin layer deposited on the build platform. As a non-limiting example, multiple resin layers are repeatedly placed on the build platform when building a 3D printed object. Therefore, a previous layer deposited during object formation can be used as a receiving component for the next resin layer. Thus, in some embodiments, the receiving component includes a build platform, a 3D printed object, a previous layer of deposited resin, or any combination thereof.

[0176] In some embodiments of the methods disclosed herein, curing at least a portion of the resin includes exposing the resin to a light source. The light source is further described herein. In some embodiments, curing at least a portion of the resin includes heating the resin. In some embodiments, curing at least a portion of the resin includes heating the resin and exposing the resin to a light source. In some embodiments, curing at least a portion of the resin includes photopolymerization.

[0177] In some embodiments of the method disclosed herein, the method further includes transporting resin from a resin injector toward a first temperature-controlled element, transporting resin from the first temperature-controlled element toward a construction platform, transporting resin from the first temperature-controlled element toward a light source, or any combination thereof. As a non-limiting example, Figure 5 The system shown illustrates the transport of resin from the resin injector to the first temperature control element, from the first temperature control element to the build platform, and from the first temperature control element to the light source.

[0178] In some embodiments of the method disclosed herein, the method further includes transporting an uncured portion of the resin from a light source and / or from a build platform to a second temperature control device. In some embodiments, the second temperature control device is a remelter as further described herein. In some embodiments, the second temperature control element is a second heating element (e.g., when the resin injector includes a heating element). As a non-limiting example, Figure 5 The system shown illustrates the transport of uncured resin from a light source and build platform to a second temperature control device (e.g., a remelter). In some embodiments, the second temperature control device heats the uncured portion of the resin to melt it. In this way, uncured resin can be applied to form another layer of resin (e.g., recycled).

[0179] In some embodiments, this disclosure provides a method for polymerizing resins, the method comprising:

[0180] Apply a first temperature to the resin;

[0181] Apply a second temperature to the resin; and

[0182] At least a portion of the resin is cured to form a cured polymer material.

[0183] In some embodiments of the methods disclosed herein, the method further includes manufacturing an object. In some embodiments, manufacturing an object includes printing resin using a 3D printer. In some embodiments, manufacturing an object includes stereolithography, digital light processing, two-photon induced photopolymerization, inkjet printing, multi-jet printing, fused deposition modeling, or any combination thereof. In some embodiments, manufacturing an object includes using a system further described herein. In some embodiments, the object is a 3D printed object. In some embodiments, the object is an orthodontic appliance (e.g., an aligner, expander, or spacer) as further described herein.

[0184] In some embodiments of the methods disclosed herein, a first portion of the resin is cured at a first temperature. In some embodiments, a second portion of the resin is cured at a second temperature. In some embodiments, the first portion of the resin is cured at a first temperature, and the second portion of the resin is cured at a second temperature. In some embodiments, curing portions of the resin at different temperatures results in portions of cured material having different polymeric and / or material properties (e.g., elongation at break, modulus, melting temperature, as a non-limiting example). Thus, temperature and curing region control can be configured to provide cured polymeric materials (e.g., the object described herein) with regional differences in polymeric and / or material properties (e.g., a first region and a second region), where said regions comprise the same base resin. Such regional differences and temperature control are further described herein.

[0185] In some embodiments, the method described herein further includes placing a first resin layer on top of a second resin layer. As a non-limiting example, the resin layers may be placed on a build platform, and then the first resin layer may be placed on top of a previously placed resin layer (i.e., the second resin layer). Such embodiments are, for example... Figures 5 to 10 As shown in the figure. In some embodiments, the method further includes applying pressure to at least one of the first resin layer or the second resin layer. In some embodiments, the application of such pressure may sufficiently heat the material to promote adhesion between the first layer and the second layer. In some embodiments, applying pressure bonds the first resin layer to the second resin layer. In some embodiments of the method described herein, the method further includes repeatedly building the resin layers.

[0186] In some embodiments of the methods described herein, the 3D printed object comes into contact with a portion of uncured resin. In some embodiments, the printed object is substantially surrounded by uncured resin (as a non-limiting example, such as...). Figures 7 to 10 As shown). In some embodiments, the printed object is surrounded by uncured resin (e.g., as shown). Figures 7 to 10 As shown). In some embodiments, the printed object is substantially not in contact with the uncured resin (as a non-limiting example, such as...). Figures 5 to 6 As shown, contact is limited to, for example, an additional uncured resin sheet to be applied to the printed object.

[0187] In some embodiments of the method described herein, the method further includes removing uncured resin from the printed object. As a non-limiting example, it is possible to obtain... Figure 8 The printed object shown is surrounded by uncured resin, and the uncured resin can be removed. In some embodiments, removing the uncured resin includes heating the object. In some embodiments, the printed object has a higher melting temperature than the uncured resin, so heating the object contained in the uncured resin to a temperature higher than the melting temperature of the uncured resin but lower than the melting temperature of the polymer material of the printed object causes the uncured resin to melt away from the printed object. In this way, after applying heat, the printed object may have no or substantially no uncured resin. In some embodiments, removing the uncured resin includes heating the object. In some embodiments, heating the object includes applying heat to a temperature higher than the melting point of the uncured resin but lower than the melting temperature of the cured resin. In some embodiments, removing the uncured resin includes applying microwave energy.

[0188] In some embodiments, removing uncured resin includes using a solvent. For example, a solvent can be used to clean a printed object in contact with uncured resin, and such solvents can be configured to dissolve or otherwise wash away the uncured resin while the cured polymer material remains intact. Therefore, in some embodiments, removing uncured resin includes cleaning the object with a solvent. In some embodiments, removing uncured resin includes using ultrasonic treatment (e.g., using an ultrasonic bath). In some embodiments, removing uncured resin includes ultrasonic treatment using a solvent and / or a heated centrifuge.

[0189] Methods of forming 3D objects using controlled temperature

[0190] This disclosure provides a method for forming a cured polymeric material (e.g., a 3D object). In some embodiments, the method applies the systems described herein. In some embodiments, the method uses systems other than those described herein. In some embodiments, changing the temperature of the photopolymerizable resin (e.g., by selectively changing the temperature) adjusts or alters the mechanical properties of the resin and / or the polymer formed from the resin during photopolymerization. Polymerizing different portions or regions (e.g., layers or cross-sections) of a resin with different temperatures or temperature histories results in regions of the polymerized material having different properties. In some embodiments, the different properties are each associated with a region temperature, as further described herein. In some embodiments, at least one of these regions is heated and / or cooled shortly before and / or during polymerization (e.g., photopolymerization). In some embodiments, at least one region is heated using an infrared light source.

[0191] Advantageously, the methods described herein can be configured for 3D printing (e.g., as further described herein) and are capable of forming two or more phase systems, as further described herein. Such phase-separated systems (e.g., multiphase materials as described herein) also provide morphology control, and thus, in some embodiments, this disclosure provides methods and materials for controlling the morphology of resin and / or cured polymer materials.

[0192] In some embodiments, this disclosure provides polymer materials and methods for forming polymer materials as described herein. In some embodiments, this disclosure provides a method comprising the following steps:

[0193] Provided resins as further disclosed herein; and

[0194] The temperature of the resin is controlled, and the resin comprises:

[0195] A first region having a first temperature; and

[0196] A second region having a second temperature; and

[0197] The resin is cured to form a polymer material.

[0198] In some embodiments, curing the resin includes exposing the resin to light to form a cured polymer material. In some embodiments, exposing the resin to light includes exposing the resin to infrared light. In some embodiments, exposing the resin to light uses a light source as further described herein. In some embodiments, the resin is cured when the resin includes a first region having a first temperature and a second region having a second temperature.

[0199] In some embodiments, the resin temperature is controlled spatially. In some embodiments, spatial control of the resin includes controlling the temperature in the xy dimension (i.e., the xy plane). As referred to herein, the xy dimension (or plane) is perpendicular to the light curing light source (which is in the z dimension). For example, Figure 5 A construction platform (140) on which a resin layer is placed is shown, thus forming the xy plane of the resin. The light source (e.g., Figure 5 The irradiation of the element (151) is substantially perpendicular to the build platform (i.e., in the z-axis). Therefore, in some embodiments, the temperature is controlled in the xy-plane (e.g., while the resin is being polymerized, such as when the resin is placed on the build platform). In some embodiments, temperature control includes spatially controlling the temperature in the xz-axis. In some embodiments, temperature control includes spatially controlling the temperature in the yz-axis. In some embodiments, the temperature of the resin is controlled in the x, y, and z dimensions (i.e., spatially controllable in three dimensions). In some embodiments, the system described herein controls the temperature of the resin as described herein.

[0200] As further described herein, in some embodiments, the resin and / or polymer material comprises more than one phase (i.e., is a multiphase material). For example, in some embodiments, the polymer material comprises a first polymeric region and a second polymeric region. In some embodiments, the resin comprises a first region and a second region. In some embodiments, the first resin region and the second resin region have at least one property that differs from each other (i.e., is distinct). In some embodiments, the at least one distinct property is selected from the group consisting of elongation at break, storage modulus, tensile modulus, residual stress, glass transition temperature, water absorption, hardness, color, transparency, hydrophobicity, lubricity, surface texture, crystallinity percentage, phase composition ratio, phase domain size, phase domain morphology, and any combination thereof. In some embodiments, the difference in surface texture includes, for example, matte regions and glossy regions. Additional textures can be formed using the methods and systems described herein.

[0201] In some embodiments, the resin comprises a crystalline material. In some embodiments, one of the first or second regions comprises a crystalline material in molten form. In some embodiments, one of the first or second regions comprises a crystalline material in crystalline form. In some embodiments, one of the first or second regions comprises a crystalline material in molten form, while the other of the first or second regions comprises a crystalline material in crystalline form.

[0202] In some embodiments, the resin composition is homogeneous. In some embodiments, the polymeric material composition is homogeneous. For example, the resin and polymer described herein may be formed from a single material, and regional variations in the resin or polymer may be due to, for example, differences in temperature control. In this way, a single resin can be used to form the 3D objects described herein with the desired properties.

[0203] In some embodiments of the methods disclosed herein, curing the resin to form a polymeric material (i.e., a polymeric polymeric material) further includes generating a first polymeric region and a second polymeric region to form a cured material, wherein each region has different material properties. In some embodiments, each region includes one or more phases. A region is a spatial dimension of the resin that is temperature-dependent, and a second region is affected by another temperature (e.g., by applying a cold plate, blower, heating lamp, infrared laser, etc.). In some embodiments, temperature affects the final cured properties of a region relative to other regions cured at other temperatures. In some embodiments, the polymeric polymeric material further includes generating 2, 3, 4, 5, or more than 5 regions in a given layer, each region having its own distinct material properties, and each region including one or more phases. In some embodiments, multiple phases are present prior to polymerization. Exemplary and non-limiting phases include solids, liquids, semi-solids, ordered, disordered, and variations in composition. In some embodiments, the first polymeric region has at least one property different from the second polymeric region. In some embodiments, the first polymeric region has at least one phase different from the second polymeric region. As a non-limiting example, the first region may be a cooled region and may include crystalline material (i.e., a solid phase) and amorphous material, while the second region may be at ambient temperature and composed of amorphous material. In some embodiments, each polymeric region includes at least one property that differs from other polymeric regions. In some embodiments, the at least one different property is selected from one or more of the following: elongation at break, storage modulus, tensile modulus, residual stress, glass transition temperature, water absorption, hardness, color, transparency, hydrophobicity, lubricity, surface texture, crystallinity percentage, phase composition ratio, phase domain size, phase domain morphology, and any combination thereof. In some embodiments, the difference in surface texture includes, for example, matte and glossy regions. Additional textures can be formed using the methods and systems described herein.

[0204] Advantageously, the methods and materials described herein can be fine-tuned to form objects with small, distinct (differentiated) features. In some embodiments, it is beneficial to accurately form features during the production of polymeric materials (e.g., in the formation of orthodontic devices), and therefore, fine control of element or dimensional dimensions is important in some embodiments. Using the systems and processes described herein, the temperature of regions of the resin layer can be selectively and precisely varied, thus enabling the fabrication of materials with high-contrast and / or gray-scale mixed material properties varying from one spatial location to a second spatial location of the material. In some embodiments, the materials formed herein comprise high-contrast material properties between multiple phases or regions. In some embodiments, the materials formed herein comprise variations in gray-scale mixed material properties between multiple phases or multiple regions. In some embodiments, fine control of region dimensions (e.g., dimensional dimensions of regions) can be applied to provide composite-like properties from a single material (e.g., forming a multiphase material from a single resin having multiple narrow or small, distinct regions, thereby providing composite-like properties to the polymeric material). In some embodiments, the multiple regions (e.g., multiple regions in a resin or multiple regions in a polymeric material) comprise dimensions from meters to micrometers, or from meters to nanometers. In some embodiments, the multiple regions include dimensions that depend on the size of the object being printed and / or the need for spatial control over the different material properties required in the printed object. In some embodiments, the size of the regions is determined by a combination of the properties required by the printed object and the techniques available for creating the regions. As a non-limiting example, regions larger than a few centimeters (x and y dimensions) can be achieved using temperature control plates, sprays (e.g., air or liquid), irradiation (e.g., infrared light, microwaves), ultrasonic energy (e.g., placement of ultrasonic transducers or rods), and other techniques. As another non-limiting example, control of regions smaller than a few centimeters (x and y dimensions) can be achieved using infrared light, lasers, LEDs, or digital light processing (DLP) with small thermally conductive temperature control plates / pins. In some embodiments, multiphoton absorption is used to heat nanoscale regions (x, y, and z dimensions). In some embodiments, the region has x and y dimensions and a z dimension smaller than the layer height. In some embodiments, the control of the region (x and y dimensions) includes at least one shaping dimension of less than 100 cm, less than 10 cm, less than 1 cm, less than 5000 μm, less than 1000 μm, less than 500 μm, less than 250 μm, less than 200 μm, less than 150 μm, less than 100 μm, less than 90 μm, less than 80 μm, less than 70 μm, less than 60 μm, less than 50 μm, less than 40 μm, less than 30 μm, less than 20 μm, less than 10 μm, or less than 1 μm.In some embodiments, the size of the phase domains includes at least one definite size of less than 250 μm, less than 200 μm, less than 150 μm, less than 100 μm, less than 90 μm, less than 80 μm, less than 70 μm, less than 60 μm, less than 50 μm, less than 40 μm, less than 30 μm, less than 20 μm, less than 10 μm, less than 5 μm, less than 1 μm, less than 500 nm, less than 100 nm, less than 10 nm, or less than 1 nm. In such embodiments, the dimensional dimensions are 1-dimensional, 2-dimensional, or 3-dimensional. In some embodiments, the size of the domains is determined by using any one of light scattering, X-rays, optical microscopy, or any combination thereof. In some embodiments, the size of the domains is determined using another measurement method. In some embodiments, the size of the domains is measured in real time (e.g., during polymerization). In some embodiments, temperature control is adjusted to control the size of the domains.

[0205] In some embodiments, the dimensional dimensions are three-dimensional, for example, having voxels. In some embodiments, the resin or polymer material includes a plurality of voxels, at least some of which each represent a region of the resin or polymer material, as further described herein. In some embodiments, the voxels have at least one dimension less than 1000 μm, less than 500 μm, less than 250 μm, less than 200 μm, less than 150 μm, less than 100 μm, less than 90 μm, less than 80 μm, less than 70 μm, less than 60 μm, less than 50 μm, less than 40 μm, less than 30 μm, less than 20 μm, or less than 10 μm. In some embodiments, a voxel has one dimension less than 1000 μm, less than 500 μm, less than 250 μm, less than 200 μm, less than 150 μm, less than 100 μm, less than 90 μm, less than 80 μm, less than 70 μm, less than 60 μm, less than 50 μm, less than 40 μm, less than 30 μm, less than 20 μm, or less than 10 μm. In some embodiments, a voxel has at least two dimensions less than 1000 μm, less than 500 μm, less than 250 μm, less than 200 μm, less than 150 μm, less than 100 μm, less than 90 μm, less than 80 μm, less than 70 μm, less than 60 μm, less than 50 μm, less than 40 μm, less than 30 μm, less than 20 μm, or less than 10 μm. In some embodiments, the voxel has two dimensions: less than 1000 μm, less than 500 μm, less than 250 μm, less than 200 μm, less than 150 μm, less than 100 μm, less than 90 μm, less than 80 μm, less than 70 μm, less than 60 μm, less than 50 μm, less than 40 μm, less than 30 μm, less than 20 μm, or less than 10 μm. In some embodiments, the voxel has three dimensions: less than 1000 μm, less than 500 μm, less than 250 μm, less than 200 μm, less than 150 μm, less than 100 μm, less than 90 μm, less than 80 μm, less than 70 μm, less than 60 μm, less than 50 μm, less than 40 μm, less than 30 μm, less than 20 μm, or less than 10 μm.

[0206] In some embodiments, the resin separates into two or more phases prior to polymerization (i.e., phase separation). In such embodiments, the separated phases during the polymerization stage can anchor these phases so that they do not mix with each other or further alter the domain size. In some embodiments, the resin phases separate upon temperature variation. For example, in some embodiments, a homogeneous resin comprising a single phase is exposed to a first temperature in a first region and a second temperature in a second region, and thereafter each of the first and second regions has distinct phase characteristics associated with a given region. In some embodiments, the resin phases separate during polymerization (e.g., during photopolymerization). In some embodiments, the resin phases separate after polymerization (e.g., after photopolymerization).

[0207] In some embodiments, controlling the temperature includes heating the resin in the first region to a first temperature. In some embodiments, controlling the temperature includes cooling the resin in the first region to a first temperature. In some embodiments, controlling the temperature includes heating the resin in the second region to a second temperature. In some embodiments, controlling the temperature includes cooling the resin in the second region to a second temperature. In some embodiments, cooling the resin in the first region and / or the second region includes cooling the resin using a cooling element as further described herein. In some embodiments, heating the resin in the first region and / or the second region includes heating the resin using a heating element as further described herein. In some embodiments, heating the resin in the first region and / or heating the resin in the second region includes exposing the resin to a light source. In some embodiments, the light source is an infrared light source.

[0208] In some embodiments, the difference between the first temperature and the second temperature is 5°C or greater, 10°C or greater, 15°C or greater, 20°C or greater, 30°C or greater, 40°C or greater, 50°C or greater, 60°C or greater, 70°C or greater, 80°C or greater, 90°C or greater, or 100°C or greater. In some embodiments, the difference between the first temperature and the second temperature is greater than or equal to 5°C and less than or equal to 50°C, greater than or equal to 5°C and less than or equal to 100°C, greater than or equal to 10°C and less than or equal to 100°C, greater than or equal to 20°C and less than or equal to 100°C, greater than or equal to 50°C and less than or equal to 100°C, greater than or equal to 50°C and less than or equal to 200°C, or greater than or equal to 100°C and less than or equal to 200°C. In some embodiments, the difference between the first temperature and the second temperature is greater than or equal to 5°C and less than or equal to 100°C. In some embodiments (e.g., when annealing the material at high temperatures to induce crystallization and / or further crystallization, or when reaching the upper limit of the solubility temperature), the difference between the first temperature and the second temperature is greater than 100°C, for example, 101°C to 200°C, 150°C to 300°C, or greater than 300°C. In some embodiments, the temperature is measured in real time (e.g., during polymerization).

[0209] In some embodiments, the polymeric resin includes photopolymerizable resins (e.g., in the case of photopolymerizable resins). In some embodiments, the method further includes providing a mask. The use of a mask allows for spatial control of the irradiation. For example, in some embodiments, a mask is used during the application of infrared light to selectively heat exposed areas of the resin, while other areas of the resin remain at different temperatures. In some embodiments, a mask is used during the application of curing light to selectively cure exposed areas of the resin to form a polymeric material, while other (i.e., unexposed) areas of the resin remain uncured.

[0210] In some embodiments, the method further includes a thermosetting polymer material. For example, thermosetting of the polymer material may increase crosslinking or otherwise modify the material properties during the formation of the 3D object. In some embodiments, the method further includes a step of photocuring the polymer material, for example, after photopolymerization. For example, in some embodiments, the polymer material formed during polymerization is exposed to a light source to further cure (e.g., crosslink) the formed object. In some embodiments, this operation is performed after printing is complete. In some embodiments, this operation is performed outside the printer (which may be referred to as post-curing, and includes heat, light, or other energy sources).

[0211] In some embodiments, the resin is applied to a substrate (e.g., the carrier platform further described herein). In some embodiments, the substrate is a glass sheet. Glass acts as a heat sink, therefore in some embodiments, it is preferred to use materials other than glass. In some embodiments, the substrate is a fluoropolymer substrate, such as a fluoropolymer film. In some embodiments, the substrate is translucent, transparent, substantially translucent, or substantially transparent. In some embodiments, the fluoropolymer substrate is translucent, transparent, substantially translucent, or substantially transparent. In some embodiments, the substrate is a silicone film and / or a polyester film. In some embodiments, the selection of the carrier material is based on resin compatibility, strength, separability of the cured material, any combination thereof, all of these factors, and / or other factors known in the art.

[0212] In some embodiments, the method further includes manufacturing an object. In some embodiments, the object is an instrument as further described herein (e.g., an orthodontic instrument). In some embodiments, the object is an orthodontic appliance, expander, or spacer. In some embodiments, manufacturing the object includes printing resin using a 3D printer. In some embodiments, manufacturing the object includes using processes and / or systems as further described herein. In some embodiments, manufacturing the object includes stereolithography, digital light processing, two-photon induced photopolymerization, inkjet printing, multi-jet printing, fused deposition modeling, or any combination thereof.

[0213] In some embodiments, the resin comprises a plurality of monomers. In some embodiments, most of the plurality of monomers are copolymerized at a first temperature and homopolymerized at a second temperature. In some embodiments, most of the plurality of monomers will copolymerize at the second temperature and homopolymerize at the first temperature. Thus, in some embodiments, the formation of homopolymer regions and copolymer regions can be controlled by applying or otherwise controlling the temperature. In some embodiments, controlling the temperature of the resin initiates a secondary chemical reaction. In some embodiments, the secondary chemical reaction includes ionothermal reactions, epoxide polymerization, ionothermal polymerization, bond breaking reactions, bond forming reactions, catalyst activation, or any combination thereof.

[0214] In some embodiments, the processes and systems described herein form a 3D object comprising: a first region including a first plurality of monomers characterized by a first set of physical properties; and a second region including a second plurality of monomers characterized by a second set of physical properties. In some embodiments, the first plurality of monomers and the second plurality of monomers are similar, while the first set of physical properties and the second set of physical properties are different. In some embodiments, the first plurality of monomers and the second plurality of monomers are substantially the same. For example, in some embodiments, the object is formed from a single resin. In some embodiments, the single resin is homogeneous. Thus, as further described herein, at least some of the processes and systems provided herein are configured to produce objects with different material properties (i.e., having multiple phases as further described herein) in the case of production from a single resin (e.g., a homogeneous resin). As further described herein, control of material properties is achieved by applying temperature control and polymerization.

[0215] In some embodiments, a 3D object is a device having a relatively high modulus in the palatal region and a relatively low modulus and high elongation at break in the tooth engagement region (e.g., an intraoral instrument as further described herein). In some embodiments, a 3D object is a device with different material properties in its base and walls (e.g., for an orthodontic appliance or retainer). In some embodiments, a 3D object is a device with different material properties within its walls (e.g., for an orthodontic appliance or retainer).

[0216] In some embodiments, the object further includes a third region comprising a third plurality of monomers and characterized by a third set of physical properties (e.g., a third phase in a multiphase system). In some embodiments, the first plurality of monomers, the second plurality of monomers, and the third plurality of monomers are similar, while the first set of physical properties, the second set of physical properties, and the third set of physical properties are different from each other. In some embodiments, the first plurality of monomers, the second plurality of monomers, and the third plurality of monomers are substantially identical. In some embodiments, the third region is more amorphous (i.e., less crystalline) than the first and second regions.

[0217] In some embodiments, the resin comprises a crystalline material. In some embodiments, the physical and / or polymeric properties of the regions are controlled by using a resin comprising a crystalline material (i.e., a resin having crystalline domains). As a non-limiting example, a resin comprising a crystalline material is a resin that comprises at least one crystalline domain when cooled. In some embodiments, the resin having a crystalline material is heated. In some embodiments, the resin having a crystalline material is heated to a point where at least some crystals melt. In some embodiments described herein, heat to melt crystals, for example, is selectively applied to regions of the resin. In this way, control over the crystallization and melting regions of the resin can be established. In some embodiments, the crystalline resin comprising crystalline and melting regions is polymerized (e.g., photopolymerized). Compared to the melting regions, polymerized crystalline domains tend to have a higher modulus. Compared to the regions comprising crystalline domains, polymerized melting regions tend to be more amorphous and more elastic. In some embodiments, in addition to light intensity, exposure time, photoinitiator concentration, the thermal history of the resin, or any combination thereof, the type of crystalline phase present is controlled by using temperature and its control. Non-limiting examples of crystalline phases include nematic phases, smectic phases, disky phases, columnar phases, cholesteric phases, layered phases, micellar phases, micellar cubic phases, hexagonal phases, and various bicontinuous phases. The addition of fillers such as amorphous silica, titanium dioxide, or talc is considered as its own phase (e.g., as a discontinuous phase relative to the rest of the material).

[0218] In some embodiments, the resin is configured to have a thermally controlled trigger. In some embodiments, the resin is configured to be a homogeneous mixture at a first temperature, but a phase-separated resin comprising two or more phases at a second temperature. In some embodiments, phase separation of the resin occurs prior to polymerization, such that the resulting photopolymerizable material comprises multiple phases. In some embodiments, the material cured during phase separation provides different physical properties compared to regions that are not phase-separated or are phase-separated to varying degrees, as further described herein. In some embodiments, phase separation is initiated upon application of polymerization (e.g., by photopolymerization of the material). In such embodiments, the resin is thermally controlled (i.e., the resin is cured at a first temperature to form a homogeneous material), but the second temperature alone does not induce the formation of additional phases—instead, when the resin is at the second temperature, curing the resin (e.g., by photopolymerization) triggers phase separation of the resin, as further described herein. Therefore, in some embodiments, the resin is configured to have both a thermally controlled trigger and a curing-controlled trigger.

[0219] In some embodiments, the resin is configured to have thermal differences in curing kinetics. For example, in some embodiments, the resin comprises monomers that are effectively copolymerized at a first temperature but homopolymerized at a second temperature. In some embodiments, the differences in curing kinetics result in different physical properties of the polymer material formed through thermal control.

[0220] In some embodiments, the resin is configured to undergo a secondary chemical reaction upon application of heat. As a non-limiting example, the heat supplied to the resin can be used to initiate a secondary chemical reaction, such as epoxide polymerization, thermal radical polymerization, ionothermal polymerization, bond breaking, bond formation, or catalyst activation. In such resins, the properties of the polymeric material can be controlled by adjusting the heat applied before or during polymerization, resulting in different material properties.

[0221] If crystallizable resins and materials are subjected to a thermal gradient, they will warp. For example, in the printing of resins containing crystallizable materials, if the printed part is allowed to cool during printing, it will warp and change shape. This can be avoided, for example, by heating the air or environment around the printed part to keep it above its crystallization temperature. Another approach is to use a top-down barrel (vat) printer, which immerses the printed part in the resin during printing (thus keeping it isothermal during printing). After printing, the part can be cleaned and then allowed to cool all at once, or it can be left uncleaned and allowed to cool all at once; both of these methods help prevent significant differences in crystallization shrinkage and subsequent warping. In some embodiments, printing while the crystalline material is crystallizing prevents warping caused by crystallization shrinkage.

[0222] polymer materials

[0223] Materials formed using temperature control

[0224] In some embodiments, the processes and systems described herein form polymer materials (e.g., form 3D printed objects), and the characteristics of the processes and systems affect the material properties. For example, in some embodiments, temperature control in the processes and systems described herein (e.g., cooling of a solid resin layer, reheating of a solid resin layer (e.g., heating the surface of the resin using an infrared heater) or any combination thereof) controls the size of domains in a system comprising more than one phase (i.e., a multiphase system). Thus, as described herein, in some embodiments, the cured polymer material comprises two or more phases. In some embodiments, two or more phases are present prior to the cooling step (i.e., before the resin passes through a first cooling element). In some such embodiments, the cooling step is configured to prevent changes in the size of the phase domains. In some embodiments, two or more phases are not present prior to the cooling step and are present during and / or after the cooling step (i.e., formed during the cooling step).

[0225] In some embodiments, the uncured resin or photocured resin comprises at least one liquid phase. In some embodiments, the uncured resin or photocured resin comprises at least one viscous liquid phase. In some embodiments, the uncured resin or photocured resin comprises at least one crystalline phase. In some embodiments, the uncured resin or photocured resin comprises at least one amorphous solid and a continuous phase. In some embodiments, the uncured resin or photocured resin comprises at least one phase, which is a complex mixture of phases. In some embodiments, at least one phase is continuous. In some embodiments, multiple phases are continuous. In some embodiments, at least two phases are continuous (i.e., having domains continuous across the material layer in one direction).

[0226] In some embodiments, the processes and systems described herein exhibit reduced shrinkage during photopolymerization compared to the shrinkage stress typically observed with other comparable materials. For example, because polymerization occurs in a solid or semi-solid state in many embodiments described herein, the polymerization shrinkage stress is reduced compared to similar materials polymerized in the form of a thermal resin (e.g., molten). In some embodiments, the reduced polymerization shrinkage stress imparts improved properties to the polymeric resin compared to similar materials formed by conventional methods. In some embodiments, materials formed using the processes and systems described herein (e.g., materials cured in a semi-solid or solid state) exhibit improved elongation at break, elongation at yield, and modulus properties compared to the same resin cured at elevated temperatures. In some embodiments, the final printed object or part is heated and / or irradiated to achieve final properties different from those present immediately after printing.

[0227] In some embodiments, the processes and systems described herein are used with crystalline resin materials. Typically, crystallizable resin materials that crystallize after polymerization shrink, resulting in defects or inaccuracies in the printed object. For example, in conventional crystallizable materials, they are photopolymerized in a hot state and then cooled, forming crystals upon cooling, resulting in localized tightening and shrinkage. In many systems and embodiments described herein, semi-solid or solid resin layers are used, and in some embodiments, such semi-solid or solid resin layers include crystalline regions. By polymerizing a resin layer in a crystalline state, the shrinkage associated with crystal formation is avoided. Therefore, in some embodiments, by polymerizing a crystallizable material in a crystalline state, the shape of the 3D object is better preserved and the accuracy of the printed object is higher compared to polymerization occurring at elevated temperatures and allowing the material to cool and crystallize. In some embodiments, polymerization of the crystalline system imparts shape memory quality to the printed part, allowing the part's shape to be distorted or bent (e.g., beyond its yield point), but the printed shape recovers upon heating (e.g., above the melting temperature of some or all of the crystal domains). In some cases, the crystal domains have a much higher melting temperature after polymerization than before polymerization, further stabilizing the printed part.

[0228] Evaluation of polymer materials

[0229] In some embodiments, this disclosure provides polymeric materials formed by the methods and / or systems described herein. The polymeric materials disclosed herein possess properties beneficial to a wide range of applications and the production of various devices. As a non-limiting example, the polymeric materials described herein can be used to produce orthodontic appliances, such as aligners. Orthodontic appliances require toughness and flexibility to move a patient's teeth while maintaining durability for use. In some embodiments, the polymeric materials have a high glass transition temperature, low creep, and low stress relaxation.

[0230] In some embodiments described herein, the polymeric materials possess properties measured after the material has been placed in an aqueous environment at 37°C for 24 hours. For example, the property values ​​of the polymeric materials can be determined using the following methods:

[0231] Stress relaxation properties can be evaluated according to ASTM D790 using the RSA-G2 instrument from TA Instruments that utilizes 3-point bending; stress relaxation can be measured at 30°C and immersed in water and reported as the remaining load after 24 hours, or as a percentage (%) of the initial load;

[0232] Storage modulus can be measured at room temperature and / or 37°C and reported in MPa;

[0233] T cured polymer material gThe evaluation can be performed using dynamic mechanical analysis (DMA), and is presented in this paper as the tanδ peak value at 1 Hz under a temperature ramp of 3 °C per minute and a sample thickness ranging from 1 mm to 600 μm.

[0234] Yield tensile strength, tensile modulus, elongation at break, yield elongation, tensile strength, and Young's modulus can be evaluated according to ASTM D1708; and

[0235] The residual flexural stress relaxation (“residual flexural stress”) after 24 hours in a humid environment at 37°C can be evaluated according to ASTM E328. In some embodiments, sample measurements are performed using a 1 mm thick sample with a 16 mm span, a strain rate of 32 mm / min, and a strain of 5%. Other methods can be used to characterize the material described herein, and the methods described above provide exemplary approaches.

[0236] As further described herein, in some embodiments, the polymeric material formed using the methods and systems described herein has more than one region or phase (e.g., a multiphase polymer). In some embodiments, such a material has more than one phase, each having distinct, determinable properties. In such embodiments, the polymeric material may have more than one (e.g., 2, 3, 4, 5, or more) of the polymeric material properties described below. For example, in some embodiments, a polymeric material having two phases is a material in which a first phase is characterized by a first tensile stress-strain curve, a second phase by a second tensile stress-strain curve, and an aggregated material (i.e., a polymeric material as a combination of phases) by a third tensile stress-strain curve. In some embodiments, the first, second, and third stress-strain curves are different. As further described herein, in some embodiments, the material properties of the polymeric material (e.g., an aggregated material of multiple phases) are determined. In some embodiments, the material properties of individual regions of the material are determined (having different properties resulting from different curing conditions and / or pre-curing thermal histories). In some embodiments, the thermal history of the material (also referred to as spatial thermal history) defines the properties within the material (e.g., within a given layer of the material).

[0237] In some embodiments, the physical properties of regions of the polymer material are determined by forming a comparable material comprising or composed of the respective phases and thereby determining the physical properties. As a non-limiting example, a photopolymer resin having multiple regions alternating between two temperatures can be formed, and the material properties of the aggregate (i.e., the polymer material) can be determined directly from the formed material, while polymer material samples formed only at the first temperature and only at the second temperature can be used to determine the properties of each corresponding phase. In some embodiments, the properties of the polymer material and the properties of at least one or at least two regions of the polymer material can be determined directly from the polymer material (e.g., by direct measurement without forming separate samples representing each region).

[0238] In embodiments, the polymer material, a first region of the polymer material, and / or a second region of the polymer material are characterized by tensile stress-strain curves showing the yield point after which the specimen continues to elongate without an increase in load. The yield stress is determined at the yield point. In embodiments, the modulus is determined by the initial slope of the stress-strain curve, or the modulus is determined as the secant modulus at 1% strain (e.g., when the stress-strain curve has no linear portion). The yield elongation is determined by the strain at the yield point. Mechanical properties may depend on the temperature at which they are measured. The test temperature may be below the expected operating temperature of the dental instrument (e.g., 35°C to 40°C). In some embodiments, the test temperature is 23 ± 2°C. For some applications, the test temperature is above 40°C. For some applications, the test temperature is below 23°C.

[0239] In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by one or more of the following: elongation at break greater than or equal to 5%; storage modulus greater than or equal to 500 MPa; tensile modulus greater than or equal to 500 MPa; residual stress greater than or equal to 0.01 MPa; and flexural modulus greater than or equal to 60 MPa after immersion in water at ambient temperature (e.g., 37°C) for 24 hours. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by an elongation at break greater than or equal to 5%. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a storage modulus greater than or equal to 500 MPa. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a tensile modulus greater than or equal to 500 MPa. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a residual stress greater than or equal to 0.01 MPa. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a flexural modulus greater than or equal to 60 MPa after immersion in water at an ambient temperature (e.g., 37°C) for 24 hours. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by two or more of the following: elongation at break greater than or equal to 5%; storage modulus greater than or equal to 500 MPa; tensile modulus greater than or equal to 500 MPa; residual stress greater than or equal to 0.01 MPa; and a flexural modulus greater than or equal to 60 MPa after immersion in water at an ambient temperature (e.g., 37°C) for 24 hours. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by: elongation at break greater than or equal to 5%; storage modulus greater than or equal to 500 MPa; tensile modulus greater than or equal to 500 MPa; residual stress greater than or equal to 0.01 MPa; and a flexural modulus greater than or equal to 60 MPa after immersion in water at an ambient temperature (e.g., 37°C) for 24 hours.

[0240] In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by one or more of the following: a tensile modulus greater than or equal to 100 MPa after being placed in an aqueous environment at 37°C for 24 hours; a yield tensile strength greater than or equal to 5 MPa after being placed in an aqueous environment at 37°C for 24 hours; a storage modulus greater than or equal to 500 MPa after being placed in an aqueous environment at 37°C for 24 hours; a residual flexural stress (“residual stress”) greater than or equal to 1.5 MPa after being placed in an aqueous environment at 37°C for 24 hours; a hardness of 60 Shore A to 85 Shore D after being placed in an aqueous environment at 37°C for 24 hours; and an elongation at break greater than or equal to 15% before and / or after being placed in an aqueous environment at 37°C for 24 hours. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a tensile modulus greater than or equal to 100 MPa after being placed in an aqueous environment at 37°C for 24 hours. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a yield tensile strength greater than or equal to 5 MPa after being placed in an aqueous environment at 37°C for 24 hours. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a storage modulus greater than or equal to 500 MPa after being placed in an aqueous environment at 37°C for 24 hours. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a residual flexural stress (“residual stress”) greater than or equal to 1.5 MPa after being placed in an aqueous environment at 37°C for 24 hours. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a hardness of 60 Shore A to 85 Shore D after being placed in an aqueous environment at 37°C for 24 hours. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by an elongation at break greater than or equal to 15% before and / or after being placed in an aqueous environment at 37°C for 24 hours.In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by: a tensile modulus greater than or equal to 100 MPa after being placed in an aqueous environment at 37°C for 24 hours; a yield tensile strength greater than or equal to 5 MPa after being placed in an aqueous environment at 37°C for 24 hours; a storage modulus greater than or equal to 500 MPa after being placed in an aqueous environment at 37°C for 24 hours; a residual flexural stress (“residual stress”) greater than or equal to 1.5 MPa after being placed in an aqueous environment at 37°C for 24 hours; a hardness of 60 Shore A to 85 Shore D after being placed in an aqueous environment at 37°C for 24 hours; and an elongation at break greater than or equal to 15% before and / or after being placed in an aqueous environment at 37°C for 24 hours.

[0241] In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a tensile modulus after 24 hours of testing in a humid environment at 37°C, ranging from 100 MPa to 3000 MPa, from 100 MPa to 2500 MPa, from 100 MPa to 2000 MPa, from 500 MPa to 3000 MPa, from 500 MPa to 2500 MPa, from 500 MPa to 2000 MPa, from 750 MPa to 3000 MPa, from 750 MPa to 2500 MPa, from 750 MPa to 2000 MPa, or from 800 MPa to 2000 MPa. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material have a tensile modulus greater than or equal to 500 MPa after 24 hours in a humid environment at 37°C. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a tensile modulus greater than or equal to 800 MPa after 24 hours in a humid environment at 37°C. In some embodiments, the tensile modulus is evaluated according to ISO-527-25B.

[0242] In some embodiments, the yield tensile strength of the polymer material, the first region of the polymer material, and / or the second region of the polymer material is from 1 MPa to 100 MPa, from 5 MPa to 85 MPa, from 10 MPa to 75 MPa, from 15 MPa to 65 MPa, from 20 MPa to 55 MPa, or from 25 MPa to 45 MPa. In some embodiments, the yield tensile strength of the polymer material, the first region of the polymer material, and / or the second region of the polymer material is from 30 MPa to 60 MPa. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material is characterized by a yield tensile strength greater than or equal to 0.1 MPa, greater than or equal to 0.5 MPa, greater than or equal to 1 MPa, greater than or equal to 10 MPa, greater than or equal to 30 MPa, greater than or equal to 40 MPa, greater than or equal to 50 MPa, greater than or equal to 60 MPa, greater than or equal to 70 MPa, greater than or equal to 80 MPa, greater than or equal to 90 MPa, or greater than or equal to 100 MPa. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a yield tensile strength greater than or equal to 30 MPa. In some embodiments, the tensile strength is evaluated according to ISO-527-2 5B.

[0243] In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a storage modulus ranging from 0.1 MPa to 4000 MPa, from 50 MPa to 2750 MPa, from 100 MPa to 2500 MPa, from 200 MPa to 2250 MPa, from 300 MPa to 3000 MPa, from 500 MPa to 3000 MPa, from 750 MPa to 3000 MPa, or from 1000 MPa to 3000 MPa after 24 hours of testing in a humid environment at 37°C. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a storage modulus of 0.1 MPa to 4000 MPa, a storage modulus of 300 MPa to 3000 MPa, or a storage modulus of 750 MPa to 3000 MPa after 24 hours of testing in a humid environment at 37°C. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a storage modulus greater than or equal to 300 MPa, greater than or equal to 400 MPa, greater than or equal to 500 MPa, greater than or equal to 600 MPa, greater than or equal to 700 MPa, greater than or equal to 800 MPa, greater than or equal to 900 MPa, or greater than or equal to 1000 MPa. In some embodiments, as further described herein, dynamic thermomechanical analysis (DMA) is used to evaluate the storage modulus.

[0244] For the polymer material, the first region of the polymer material, and / or the second region of the polymer material, it is advantageous that the residual bending stress after 24 hours of testing in a humid environment at 37°C is 5% or greater. In some embodiments, the residual bending stress is 5% or greater, 10% or greater, 15% or greater, 20% or greater, 25% or greater, 30% or greater, 35% or greater, 40% or greater, 50% or greater, 60% or greater, or 70% or greater. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material is characterized by a residual bending stress greater than 10% after 24 hours of testing in a humid environment at 37°C. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material is characterized by a residual bending stress greater than 20% after 24 hours of testing in a humid environment at 37°C. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material is characterized by a residual bending stress greater than 25% after 24 hours of testing in a humid environment at 37°C. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized in that, after 24 hours in a humid environment at 37°C, the residual flexural stress is 5% to 50%, 10% to 50%, 15% to 50%, 20% to 50%, 25% to 50%, or 30% to 50% of the initial load. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized in that, after 24 hours in a humid environment at 37°C, the residual flexural stress is 5% to 100%, 10% to 100%, 15% to 100%, 20% to 100%, 25% to 100%, 30% to 100%, 40% to 100%, 50% to 100%, 60% to 100%, 70% to 100%, 80% to 100%, or 90% to 100% of the initial load. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized in that the residual flexural stress after 24 hours in a humid environment at 37°C is 20% to 45% of the initial load. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized in that the residual flexural stress after 24 hours in a humid environment at 37°C is greater than 50% of the initial load. In some embodiments, the residual flexural stress is measured using a 1 mm thick sample. In some embodiments, the residual flexural stress is evaluated according to ASTM E328.

[0245] In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a residual flexural stress of 0.01 MPa to 15 MPa, 0.05 MPa to 15 MPa, 0.1 MPa to 15 MPa, 0.5 MPa to 15 MPa, 1 MPa to 15 MPa, 2 MPa to 15 MPa, 3 MPa to 15 MPa, 4 MPa to 15 MPa, 5 MPa to 15 MPa, or 10 MPa to 15 MPa after 24 hours in a humid environment at 37°C. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a residual flexural stress of 2 MPa to 15 MPa after 24 hours in a humid environment at 37°C. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a flexural stress greater than or equal to 0.1 MPa, greater than or equal to 0.5 MPa, greater than or equal to 1 MPa, greater than or equal to 1.5 MPa, greater than or equal to 2 MPa, greater than or equal to 2.5 MPa, greater than or equal to 3 MPa, greater than or equal to 4 MPa, greater than or equal to 5 MPa, greater than or equal to 6 MPa, greater than or equal to 7 MPa, greater than or equal to 8 MPa, greater than or equal to 9 MPa, greater than or equal to 10 MPa, or greater than or equal to 15 MPa after 24 hours in a humid environment at 37°C. In some embodiments, the flexural stress is evaluated according to ASTM E328.

[0246] In some embodiments, the polymer material, a first region of the polymer material, and / or a second region of the polymer material have stress relaxation measurements determined by ASTM D790 in a 3-point bending test with a 5% deviation. In some embodiments, stress relaxation can be measured by monitoring the stress that varies over time due to steady-state strain. The degree of stress relaxation also depends on temperature, relative humidity, and other applicable conditions (e.g., the presence of water). In embodiments, the stress relaxation test conditions are a temperature of 37 ± 2°C at 100% relative humidity or a temperature of 37 ± 2°C in water. Stress relaxation properties can be evaluated using an RSA-G2 instrument from TA Instruments via a 3-point bending, 5% strain method. Stress relaxation is typically measured at 37°C and 100% relative humidity and reported as the residual load after 2 hours, or expressed as a percentage (%) of the initial load or in MPa. In some embodiments, the residual stress in the polymer material, the first region of the polymer material, and / or the second region of the polymer material is greater than or equal to 5% of the initial load. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material is characterized by residual stress ranging from 5% to 45% of the initial load. In some aspects, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized in that the residual stress is 20% to 45% of the initial load. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized in that the residual stress is greater than or equal to 20% or greater than or equal to 35% of the initial load. In some embodiments, the stress relaxation measurement of the polymer material after 24 hours in water at 30°C has a value greater than 10% of the initial stress. In some embodiments, the stress relaxation measurement of the polymer material, the first region of the polymer material, and / or the second region of the polymer material after 24 hours in water at 30°C has a value greater than 15%, greater than 20%, greater than 25%, greater than 30%, greater than 35%, greater than 40%, greater than 45%, or greater than 50% of the initial stress. In some embodiments, the residual stress of the polymer material, the first region of the polymer material, and / or the second region of the polymer material is greater than or equal to 0.01 MPa. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a residual stress of 0.01 MPa to 15 MPa. In other aspects, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by a residual stress of 2 MPa to 15 MPa.

[0247] In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized in that the residual stress is 5% to 85% of the initial load, for example, 5% to 45%, 15% to 85%, or 20% to 45% of the initial load. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized in that the residual stress is 0.01 MPa to 15 MPa, for example, 2 MPa to 15 MPa. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized in that the residual stress is greater than or equal to 20% of the initial load. In some embodiments, the residual stress is evaluated according to ASTM E328.

[0248] In some embodiments, it is advantageous for the polymer material, the first region of the polymer material, and / or the second region of the polymer material to have a high flexural modulus, thereby forming a relatively rigid material. In some embodiments, the residual flexural modulus of the polymer material, the first region of the polymer material, and / or the second region of the polymer material is 50 MPa or greater, 60 MPa or greater, 70 MPa or greater, 80 MPa or greater, 90 MPa or greater, 100 MPa or greater, 125 MPa or greater, or 150 MPa or greater. In some embodiments, the residual flexural modulus is measured after 24 hours in a humid environment at the operating temperature. In some embodiments, the operating temperature is 37°C. In some embodiments, the flexural modulus is evaluated according to ASTM D790.

[0249] In some other embodiments, it is advantageous that the polymer material, the first region of the polymer material, and / or the second region of the polymer material have relatively low residual flexural stress, thereby forming a material that is not overly stiff. In some embodiments, the residual flexural stress of the polymer material, the first region of the polymer material, and / or the second region of the polymer material is 80 MPa or less, 70 MPa or less, 60 MPa or less, 55 MPa or less, 50 MPa or less, or 45 MPa or less. In some embodiments, the residual flexural stress is measured after 24 hours in a humid environment at the operating temperature. In some embodiments, the operating temperature is 37°C. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material is characterized by a residual flexural stress of 0.01 MPa to 15 MPa, or a residual stress of 2 MPa to 15 MPa, after 24 hours of testing in a humid environment at 37°C. In some embodiments, the residual stress is evaluated according to ASTM E328.

[0250] In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material will have residual bending stress after a period of use. As a non-limiting example, orthodontic appliances (e.g., braces) may be formed of polymer materials with high bending stress, but after the appliance is applied to a patient's teeth, there may be a significant and rapid decrease in bending stress (e.g., within minutes). This decrease in bending stress may follow an exponential decline curve tending asymptotically over the expected lifespan of the appliance (e.g., over several weeks for orthodontic appliances). In some embodiments, the residual bending stress of the polymer material, the first region of the polymer material, and / or the second region of the polymer material after a period of use is 90 MPa or less, 85 MPa or less, 80 MPa or less, 75 MPa or less, 70 MPa or less, 65 MPa or less, 60 MPa or less, 55 MPa or less, or 50 MPa or less. In some embodiments, the residual bending stress of the polymer material, the first region of the polymer material, and / or the second region of the polymer material after a period of use is 80 MPa or less. In some embodiments, the usage period is 1 minute, 5 minutes, 10 minutes, 30 minutes, 1 hour, 24 hours, 48 ​​hours, 1 week, 2 weeks, 1 month, 2 months, 6 months, 1 year, 2 years, or more than 2 years. As a non-limiting example, an orthodontic appliance composed of a polymer material placed on a patient's teeth is removed after 10 minutes and has a bending stress of 70 MPa, which results in the polymer material being characterized by a residual bending stress of 70 MPa after a period of use, wherein the time period is 10 minutes. In some embodiments, the residual stress is evaluated according to ASTM E328.

[0251] In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by an elongation at break greater than 10%, greater than 20%, greater than 30%, an elongation at break of 5% to 250%, an elongation at break of 20% to 250%, or an elongation at break value between 40% and 250%. In some embodiments, the elongation at break is measured under dry conditions (e.g., a dry environment). In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by an elongation at break greater than 10%, greater than 20%, greater than 30%, 5% to 250%, 20% to 250%, or an elongation at break value between 40% and 250% after testing in a humid environment at 37°C for 24 hours. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by an elongation at break greater than 10%, greater than 20%, greater than 30%, between 5% and 250%, between 20% and 250%, or between 40% and 250% after testing in a dry environment and a humid environment at 37°C for 24 hours. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are characterized by an elongation at break greater than or equal to 5%, greater than or equal to 10%, greater than or equal to 20%, greater than or equal to 30%, greater than or equal to 40%, or greater than or equal to 50%. In some embodiments, the elongation at break is evaluated according to ASTM D1708-25B.

[0252] In some embodiments, the yield elongation of the polymer material, the first region of the polymer material, and / or the second region of the polymer material is greater than 4%, greater than 5%, greater than 6%, greater than 7%, greater than 8%, greater than 9%, greater than 10%, greater than 11%, greater than 12%, greater than 13%, greater than 14%, or greater than 15%. In some embodiments, the yield elongation of the polymer material, the first region of the polymer material, and / or the second region of the polymer material is 4% to 10% or 5% to 15%. In some embodiments, the yield elongation is measured under dry conditions (e.g., a dry environment). In some embodiments, the yield elongation of the polymer material, the first region of the polymer material, and / or the second region of the polymer material after being tested in a humid environment at 37°C for 24 hours is greater than 4%, greater than 5%, greater than 6%, greater than 6%, greater than 7%, greater than 8%, greater than 9%, greater than 10%, greater than 11%, greater than 12%, greater than 13%, greater than 14%, or greater than 15%. In some embodiments, the yield elongation of the polymer material, the first region of the polymer material, and / or the second region of the polymer material after testing in a humid environment at 37°C for 24 hours is 4% to 10% or 5% to 15%. In some embodiments, the yield elongation of the polymer material, the first region of the polymer material, and / or the second region of the polymer material after testing in a dry environment and in a humid environment at 37°C for 24 hours is greater than 4%, greater than 5%, greater than 6%, greater than 6%, greater than 7%, greater than 8%, greater than 9%, greater than 10%, greater than 11%, greater than 12%, greater than 13%, greater than 14%, or greater than 15%. In some embodiments, the yield elongation of the polymer material, the first region of the polymer material, and / or the second region of the polymer material after testing in a dry environment and in a humid environment at 37°C for 24 hours is 4% to 10% or 5% to 15%. In some embodiments, the yield elongation is evaluated according to ISO 527-2 5B.

[0253] In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material have at least one glass transition temperature (T0) ranging from 0°C to 150°C. gIn some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material have at least one glass transition temperature greater than 60°C. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material have at least one glass transition temperature greater than 75°C. In some embodiments, at least one glass transition temperature is from 0°C to 200°C, from 0°C to 140°C, from 0°C to 20°C, from 20°C to 40°C, from 40°C to 60°C, from 60°C to 80°C, from 80°C to 100°C, from 100°C to 120°C, from 120°C to 140°C, from 140°C to 160°C, from 160°C to 180°C, from 180°C to 200°C, from 0°C to 35°C, from 35°C to 65°C, from 65°C to 100°C, from 0°C to 50°C, or from 50°C to 100°C. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material have a temperature range of 0°C to 10°C, 10°C to 20°C, 20°C to 30°C, 30°C to 40°C, 40°C to 50°C, 50°C to 60°C, 60°C to 70°C, 70°C to 80°C, 80°C to 90°C, 90°C to 100°C, 100°C to 110°C, 110°C to 120°C, 120°C to 130°C, 130°C to 140°C, or 140°C to 150°C. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material have a temperature ranging from -100°C to 40°C, from -80°C to 10°C, from -70°C to 0°C, from -70°C to -10°C, from -70°C to -20°C, from -70°C to -30°C, from -70°C to -40°C, from -70°C to -50°C, or from -80°C to -40°C. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material have at least two glass transition temperatures. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material have a first T temperature less than 40°C. g and the second T greater than 60℃ g The first T below 0℃ g and the second T greater than 60℃ g The first T below 0℃ g and the second T greater than 75℃ g or the first T temperature less than -20℃ g and the second T greater than 80℃ g In some embodiments, the glass transition temperature is evaluated by dynamic thermomechanical analysis as the tanδ peak when running at 1 Hz with a temperature ramp of 2 °C per minute.

[0254] In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material have at least one melting temperature (T) ranging from 0°C to 300°C. m (Amorphous and / or crystalline). In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material have at least one melting transition temperature greater than 60°C. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material have at least one melting transition temperature greater than 75°C. In some embodiments, at least one melting transition temperature is from 0°C to 300°C, from 0°C to 140°C, from 0°C to 20°C, from 20°C to 40°C, from 40°C to 60°C, from 60°C to 80°C, from 80°C to 100°C, from 100°C to 120°C, from 120°C to 140°C, from 140°C to 160°C, from 160°C to 180°C, from 180°C to 200°C, from 0°C to 35°C, from 35°C to 65°C, from 65°C to 100°C, from 0°C to 50°C, or from 50°C to 100°C.

[0255] In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are clear, substantially transparent, mostly transparent, or opaque. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are transparent. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are substantially transparent. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are mostly transparent. In some embodiments, greater than 70%, greater than 80%, greater than 90%, greater than 95%, or greater than 99% of visible light passes through the polymer material, the first region of the polymer material, and / or the second region of the polymer material. Transparency can be measured using a UV-V spectrophotometer. In some embodiments, transparency is measured by measuring the passage of transparency wavelengths. In some embodiments, transparency wavelengths greater than 70%, greater than 80%, greater than 90%, greater than 95%, or greater than 99% can pass through the polymer material, the first region of the polymer material, and / or the second region of the polymer material. In some embodiments, the transparency wavelength is in the visible light range (i.e., from 400 nm to 800 nm), the infrared range, or the ultraviolet range. In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are colorless. In other embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are white, off-white, or mostly transparent with a white tint, as perceived by the human eye.

[0256] In some embodiments, after 24 hours in a humid environment at 37°C, greater than 20%, greater than 30%, greater than 40%, greater than 50%, greater than 60%, greater than 70%, greater than 80%, greater than 90%, or greater than 95% of visible light penetrates the polymer material, the first region of the polymer material, and / or the second region of the polymer material. In some embodiments, after 24 hours in a humid environment at 37°C, greater than 70% of visible light penetrates the polymer material, the first region of the polymer material, and / or the second region of the polymer material.

[0257] In some embodiments, the material includes more than one region, wherein each region has characteristic properties different from one or more other regions. The differences in material properties can form a bulk material having bulk characteristics different from the individual regions. As a non-limiting example, alternating layers of regions cured under different conditions can produce a composite-like structure with bulk material characteristics. As another non-limiting example, as described herein, different regions can be produced within a given layer by controlling the curing conditions (and / or temperature). In many embodiments, regions with very different and unique material properties are produced. As a non-limiting example, the material may include a Tc with a temperature greater than 80°C. g and / or T m One region of the material, while another region of the material has a temperature T below 0°C. g In some embodiments, properties within or between regions are grayscaled. As a non-limiting example, a region is exposed to a temperature gradient such that different amounts of crystallinity are formed or present across the region after polymerization in that region. This grayscale control of properties is advantageous. In some non-limiting embodiments, this grayscale of material across regions is achieved by using one or more of the following variables across the regions: changing light intensity, changing light dose, changing resin temperature during curing, changing resin temperature before curing, changing pressure applied to the resin before and / or during curing, or any combination thereof. In some embodiments, grayscale is achieved in the z-dimensional by similar variable control and, for example, control of light blocker concentration (or pigment concentration). In some embodiments, adding chemicals to the outer surfaces of each layer (e.g., top and / or bottom surfaces) using a funnel or sprayer also provides a mechanism for controlling properties in the x, y, and z dimensions.

[0258] In some embodiments, the polymer material, the first region of the polymer material, and / or the second region of the polymer material are biocompatible, bioinert, or a combination thereof.

[0259] In some embodiments, polymer materials are formed using photopolymerization via 3D printing (i.e., additive manufacturing). In some embodiments, the polymer material may be used for coatings, molds, injection molding machines, or other manufacturing methods that use or may use light during the curing process. In some embodiments, the polymer material, a first region of the polymer material, and / or a second region of the polymer material are well-suited for applications requiring, for example, solvent resistance, moisture resistance, water resistance, creep resistance, or resistance to heat deformation.

[0260] Printable resin

[0261] The polymeric materials disclosed herein can be formed from printable resins (e.g., uncured solid resin layers or sheets). As further described herein, systems and methods are provided for using printable resins (e.g., resin sheets) during the formation of 3D printed objects. As used herein, printable resin refers to the uncured solid resin described herein (e.g., sheets, rolls, or layers of uncured resin) and also to the liquid resin described herein (e.g., hot-melt resin injected into the system described herein prior to the formation of solid resin).

[0262] In some embodiments, the printable resin includes an initiator. In some embodiments, the initiator is a photoinitiator. Photoinitiators can be used for a variety of purposes, including for curing polymers, including those that can utilize light to activate and initiate the polymerization of polymerizable components of the formulation. In embodiments, the photoinitiator is a radical photoinitiator and / or a cationic initiator. In some embodiments, the photoinitiator is a type I photoinitiator that undergoes unimolecular bond cleavage to generate free radicals. In another embodiment, the photoinitiator is a type II photoinitiator that undergoes a bimolecular reaction to generate free radicals. Common type I photoinitiators include, but are not limited to, benzoin ethers, benzil ketals, α-dialkoxy-acetophenones, α-hydroxy-alkyl phenones, and acyl-phosphine oxides. Common type II photoinitiators include benzophenone / amine and thioxanone / amine. Cationic initiators include aryl diazonium salts, diaryl iodides, and triaryl sulfonium salts. In some embodiments, the photoinitiator comprises diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, (2,4,6-trimethylbenzoyl)phenylphosphine ester, or a combination thereof. In some embodiments, the photoinitiator comprises a radical photoinitiator, a cationic photoinitiator, and / or a photoalkalizing agent. In some embodiments, the photoinitiator is a type I photoinitiator that undergoes unimolecular bond cleavage to generate a radical, or a type II photoinitiator that undergoes a bimolecular reaction to generate a radical. In some embodiments, the type I photoinitiator is benzoin ether, benzoyl ketal, α-dialkoxy-acetophenone, α-hydroxy-alkylphenyl ketone, or acyl-phosphine oxide. In some embodiments, the type II photoinitiator is benzophenone / amine, camphorquinone / amine, or thioxanone / amine. In some embodiments using a type II photoinitiator, a donor other than an amine (e.g., a borate) is used. In some embodiments, the cationic photoinitiator is an aryl diazonium salt, a diaryl iodide salt, or a triaryl sulfonium salt. In some embodiments, the photoinitiator undergoes type I, type II, electron transfer, and / or hydrogen abstraction.

[0263] In some embodiments, the photoinitiator uses light energy to initiate photopolymerization. In some embodiments, the photoinitiator initiates photopolymerization by exposure to light energy in the following ranges: 800 nm to 250 nm, 800 nm to 350 nm, 800 nm to 450 nm, 800 nm to 550 nm, 800 nm to 650 nm, 600 nm to 250 nm, 600 nm to 350 nm, 600 nm to 450 nm, or 400 nm to 250 nm. In some embodiments, the photoinitiator initiates photopolymerization after absorbing two photons, which can use light of a longer wavelength to initiate photopolymerization. In some embodiments, more than one photoinitiator is used, and each is activated at a different wavelength and / or at a different time. As a non-limiting example, one photoinitiator may be activated during the printing stage, while a second photoinitiator may be activated during the post-curing stage. In some embodiments using more than one initiator, they are activated at different wavelengths or they are activated using different energy sources (e.g., heat, ultrasound, infrared, radio frequency heating); the activation of each initiator may occur simultaneously (e.g., simultaneous thermal activation and infrared activation) or at different times.

[0264] In some embodiments, the resin includes more than one initiator (e.g., 2, 3, 4, 5, or more than 5 initiators). In some embodiments, the initiator is a thermal initiator. In some embodiments, the thermal initiator includes an organic peroxide. In some embodiments, the thermal initiator includes an azo compound, an inorganic peroxide, an organic peroxide, or any combination thereof.In some embodiments, the thermal initiator is selected from the group consisting of: tert-amyl peroxybenzoate, 4,4-azobis(4-cyanovaleric acid), 1,1'-azobis(cyclohexanecarbonitrile), 2,2'-azobisisobutyronitrile (AIBN), benzoyl peroxide. peroxide), 2,2-bis(tert-butylperoxy)butane, 1,1-bis(tert-butylperoxy)cyclohexane, 2,5-bis(tert-butylperoxy-2,5-dimethylhexane), 2,5-bis(tert-butylperoxy-2,5-dimethylhexane, 2,5-bis(tert-butylperoxy)-2,5-dimethyl-3-hexyne 2,5-bis(tert-butylperoxy)-2,5-dimethyl-3-hexyne, bis(1-(tert-butylperoxy)-3,3,5-trimethylcyclohexane), tert-butylhydroxyperoxide, tert-butylperacetate, tert-butylperoxide peroxide, tert-butylperoxybenzoate, tert-butylperoxyisopropyl carbonate, cumene hydroperoxide, cyclohexanone peroxide, dicumyl peroxide, lauroyl peroxide, 2,4-pentanedione peroxide, peracetic acid, potassium persulfate, and their derivatives and combinations thereof.In some embodiments, the thermal initiator includes azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), benzoyl peroxide, or a combination thereof.

[0265] In some embodiments, the printable resin includes 0.01-10 wt%, 0.02-5 wt%, 0.05-4 wt%, 0.1-3 wt%, 0.1-2 wt%, or 0.1-1 wt% of an initiator. In some embodiments, the printable resin includes 0.1-2 wt% of an initiator. In some embodiments, the printable resin includes 0.01-10 wt%, 0.02-5 wt%, 0.05-4 wt%, 0.1-3 wt%, 0.1-2 wt%, or 0.1-1 wt% of a photoinitiator. In some embodiments, the printable resin includes 0.1-2 wt% of a photoinitiator. In some embodiments, the printable resin includes 0 to 10 wt%, 0 to 9 wt%, 0 to 8 wt%, 0 to 7 wt%, 0 to 6 wt%, 0 to 5 wt%, 0 to 4 wt%, 0 to 3 wt%, 0 to 2 wt%, 0 to 1 wt%, or 0 to 0.5 wt% of a thermal initiator. In some embodiments, the printable resin includes 0 to 0.5 wt% of a thermal initiator.

[0266] In some embodiments, the printable resin further includes a reactive diluent, a crosslinking modifier, a light-blocking agent, a solvent, a glass transition temperature modifier, a thermal initiator, a catalyst for activating the activatable unit, or a combination thereof. In some embodiments, the reactive diluent, crosslinking modifier, light-blocking agent, solvent, glass transition temperature modifier, thermal initiator, catalyst, or a combination thereof is delivered via a device such as a funnel or a sprayer (e.g., Figure 6 , Figure 8 and Figure 9 The apparatus (190) is added to the resin. In some embodiments, the resin further includes at least one of a polymerization catalyst, inhibitor, plasticizer, surface energy modifier, pigment, dye, filler, binder, crystallization seed, crystallization catalyst, biological agent, catalyst for selectively breaking bonds, or any combination thereof. In some embodiments, the polymerization catalyst, inhibitor, plasticizer, surface energy modifier, pigment, dye, filler, binder, crystallization seed, crystallization catalyst, biological agent, catalyst for selectively breaking bonds, or any combination thereof is added to the resin via an apparatus such as a funnel or sprayer (e.g., Figure 6 , Figure 8 and Figure 9 The device (190) is added to the resin.

[0267] In some embodiments, the viscosity of the printable resin at the printable temperature (i.e., the temperature at which the object is printed, such as when it is photopolymerized) is less than 60 Pa·s, less than 50 Pa·s, less than 40 Pa·s, less than 30 Pa·s, less than 20 Pa·s, less than 10 Pa·s, less than 9 Pa·s, less than 8 Pa·s, less than 7 Pa·s, less than 6 Pa·s, less than 5 Pa·s, less than 4 Pa·s, less than 3 Pa·s, less than 2 Pa·s, or less than 1 Pa·s. In some embodiments, the printable temperature is at, above, or below room temperature. In some embodiments, the printable temperature is 0°C to 25°C, 25°C to 40°C, 40°C to 100°C, or 25°C to 150°C. In some embodiments, the resin has a viscosity of 0.5 Pa·s to 20 Pa·s at the printable temperature. In some embodiments, the printable temperature is 70°C to 110°C. In some embodiments, the printable temperature is 90°C. In some embodiments, the viscosity of the printable resin at 90°C is from 0.5 Pa·s to 20 Pa·s. In some embodiments, the viscosity of the printable resin at 90°C is from 20 Pa·s to 60 Pa·s.

[0268] In some embodiments, the viscosity of the printable resin is less than 60 Pa·s, less than 50 Pa·s, less than 40 Pa·s, less than 30 Pa·s, less than 20 Pa·s, less than 10 Pa·s, less than 9 Pa·s, less than 8 Pa·s, less than 7 Pa·s, less than 6 Pa·s, less than 5 Pa·s, less than 4 Pa·s, less than 3 Pa·s, less than 2 Pa·s, or less than 1 Pa·s at the injection temperature (e.g., the temperature at which the resin is injected). In some embodiments, the injection temperature is at, above, or below room temperature. In some embodiments, the injection temperature is 0°C to 25°C, 25°C to 40°C, 40°C to 100°C, or 25°C to 150°C. In some embodiments, the viscosity of the resin at the injection temperature is 0.5 Pa·s to 20 Pa·s. In some embodiments, the injection temperature is 70°C to 110°C. In some embodiments, the injection temperature is 90°C. In some embodiments, the viscosity of the printable resin at 90°C is 0.5 Pa·s to 20 Pa·s. In some embodiments, the viscosity of the printable resin at 90°C is from 20 Pa·s to 60 Pa·s.

[0269] The dynamic viscosity of a fluid represents its resistance to shear flow. The SI unit for dynamic viscosity is poiseuille (Pa·s). Dynamic viscosity is usually given in centipoise, where 1 centipoise (cP) is equivalent to 1 mPa·s. Kinematic viscosity is the ratio of dynamic viscosity to fluid density; the SI unit is m³ / s. 2 / s. Apparatus used for measuring viscosity includes viscometers and rheometers. The viscosity of the components described herein can be measured using a rheometer at 110°C. For example, the MCR 301 rheometer from Anton Paar can be used for rheological measurements in rotational mode (PP-25, 50 s⁻¹, 50-115°C, 3°C / min).

[0270] In some embodiments, the printable resin includes a polymerization catalyst. In some embodiments, the polymerization catalyst includes a tin catalyst, a platinum catalyst, a rhodium catalyst, a titanium catalyst, a silicon catalyst, a palladium catalyst, a metal trifluoromethanesulfonate catalyst, a boron catalyst, a bismuth catalyst, or any combination thereof. Non-limiting examples of titanium catalysts include di-n-butylbutoxychlorotin, di-n-butyldiacetoxytin, di-n-butyldilauryltin, dimethyldineodecanoatetin, dioctyldilauryltin, tetramethyltin, and dioctylbis(2-ethylhexylmaleate)tin. Non-limiting examples of platinum catalysts include platinum-divinyltetramethyl-disiloxane complex, platinum-cyclovinylmethyl-siloxane complex, platinum-octanal complex, and platinumcarbonylcyclovinylmethylsiloxane complex. Non-limiting examples of rhodium catalysts include tris(dibutylsulfide)rhodium trichloride. Non-limiting examples of titanium catalysts include titanium isopropoxide, titanium 2-ethyl-hexoxide, titanium chloride triisopropoxide, titanium ethoxide, and titanium diisopropoxide bis(ethylacetoacetate). Non-limiting examples of silicon catalysts include tetramethylammonium siloxanolate and tetramethylsilylmethyl-trifluoromethanesulfonate.Non-limiting examples of palladium catalysts include tetrakis(triphenylphosphine)palladium(0). Non-limiting examples of metal trifluoromethanesulfonate catalysts include scandium trifluoromethanesulfonate, lanthanum trifluoromethanesulfonate, and ytterbium trifluoromethanesulfonate. Non-limiting examples of boron catalysts include tris(pentafluorophenyl)boron. Non-limiting examples of bismuth catalysts include bismuth-zincneodecanoate, bismuth 2-ethylhexanoate, metal carboxylates of bismuth and zinc, and metal carboxylates of bismuth and zirconium.

[0271] In some embodiments, the printable resin includes a polymerization inhibitor to stabilize the composition and prevent premature polymerization. In some embodiments, the polymerization inhibitor is a photopolymerization inhibitor (e.g., oxygen). In some embodiments, the polymerization inhibitor is a phenolic compound (e.g., BHT). In some embodiments, the polymerization inhibitor is a stable free radical (e.g., 2,2,4,4-tetramethylpiperidinyl-1-oxy radical, 2,2-diphenyl-1-picrylhydrazyl radical, galvinoxyl radical, or triphenylmethyl radical). In some embodiments, more than one polymerization inhibitor is present in the resin. In some embodiments, the polymerization inhibitor acts as a free radical scavenger. In some embodiments, the polymerization inhibitor is an antioxidant, a hindered amine light stabilizer (HAL), a hindered phenol, or an inactivating free radical (e.g., a peroxide compound). In some embodiments, the polymerization inhibitor is selected from the group consisting of: 4-tert-butylpyrocatechol, tert-butylhydroquinone, 1,4-benzoquinone, 6-tert-butyl-2,4-xylenol, 2-tert-butyl-1,4-benzoquinone, 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butylphenol, 1,1-diphenyl-2-picrylhydrazyl free radical, hydroquinone, 4-methoxyphenol, phenothiazine, any derivative thereof, and any combination thereof.

[0272] In some embodiments, the printable resin includes a light-blocking agent to dissipate UV radiation. In some embodiments, the light-blocking agent absorbs specific UV energy values ​​and / or ranges. In some embodiments, the light-blocking agent is a UV light absorber, pigment, masterbatch, or IR light absorber. In some embodiments, the light-blocking agent includes benzotriazole (e.g., 2-(2'-hydroxy-phenylbenzotriazole), hydroxyphenyltriazine, oxanilide, benzophenone, or combinations thereof).

[0273] In some embodiments, the printable resin includes fillers. In some embodiments, the fillers include calcium carbonate (i.e., chalk), kaolin, metakaolinite, kaolinite derivatives, magnesium hydroxide (i.e., talc), calcium silicate (i.e., wollastonite), glass fillers (e.g., glass beads, short glass fibers, or long glass fibers), nanofillers (e.g., nanoplatelets, nanofibers, or nanoparticles), silica fillers (e.g., mica, silica gel, fumed silica, or precipitated silica), carbon black, dolomite, barium sulfate, ATH Al(OH)3, MDH Mg(OH)2, diatomaceous earth, magnetite, halloysite, zinc oxide, titanium dioxide, cellulose, lignin, carbon fillers (e.g., chopped carbon fibers or carbon fibers), derivatives thereof, or combinations thereof.

[0274] In some embodiments, the printable resin comprises pigments, dyes, or combinations thereof. Pigments are typically suspensions of solids insoluble in the resin. Dyes are typically dissolved in the printable resin. In some embodiments, the pigments comprise inorganic pigments. In some embodiments, inorganic pigments comprise iron oxide, barium sulfide, zinc oxide, antimony trioxide, yellow iron oxide, red iron oxide, ferric ammonium ferrocyanide, chrome yellow, carbon black, or aluminum flakes. In some embodiments, the pigments comprise organic pigments. In some embodiments, organic pigments comprise azo pigments, anthraquinone pigments, copper phthalocyanine (CPC) pigments (e.g., phthalocyanine blue or phthalocyanine green), or combinations thereof. In some embodiments, the dyes comprise azo dyes (e.g., diarylide or Sudan dyes), anthraquinones (e.g., Oil Blue A or Disperse Red 11), or combinations thereof.

[0275] In some embodiments, the printable resin includes a surface energy modifier. In some embodiments, the surface energy modifier can aid in the process of releasing the polymer from the mold. In some embodiments, the surface energy modifier can act as a defoamer. In some embodiments, the surface energy modifier includes a defoamer, degassing agent, hydrophobic agent, leveling agent, wetting agent, or agent for adjusting the flow properties of the printable resin. In some embodiments, the surface energy modifier includes an alkoxylated surfactant, a silicone surfactant, a sulfosuccinate, a fluorinated polyacrylate, a fluoropolymer, a silicone, a star polymer, an organically modified silicone, or any combination thereof.

[0276] In some embodiments, the printable resin includes a plasticizer. The plasticizer may be a non-volatile material that reduces interactions between polymer chains, thereby lowering the glass transition temperature, melt viscosity, and elastic modulus. In some embodiments, the plasticizer includes dicarboxylic ester plasticizers, tricarboxylic ester plasticizers, trimellitate, adipate, sebacate, maleate, or bio-based plasticizers. In some embodiments, the plasticizer comprises a dicarboxylic acid ester or a tricarboxylic acid ester, including diesters, phthalates, bis(2-ethylhexyl) phthalate (DEHP), di(2-propylheptyl) phthalate (DPHP), diisononyl phthalate (DINP), di-n-butyl phthalate (DBP), butyl benzyl phthalate (BBzP), diisodecyl phthalate (DIDP), dioctyl phthalate (DOP), diisooctyl phthalate (DIOP), diethyl phthalate (DEP), diisobutyl phthalate (DIBP), di-n-hexyl phthalate, derivatives thereof, or combinations thereof. In some embodiments, the plasticizer comprises trimellitate, including trimethyl trimellitate (TMTM), tri-(2-ethylhexyl) trimellitate (TEHTM), tri-(n-octyl, n-decyl) trimellitate (ATM), tri-(heptyl, nonyl))triellitate (LTM), n-octyl trimellitate (OTM), trioctyl trimellitate, derivatives thereof, or combinations thereof. In some embodiments, the plasticizer comprises adipate, including bis(2-ethylhexyl)adipate (DEHA), dimethyl adipate (DMAD), monomethyl adipate (MMAD), dioctyl adipate (DOA), bis[2-(2-butoxyethoxy)ethyl]adipate (Bis[2-(2-butoxyethoxy)ethyl]adipate), dibutyl adipate, diisobutyl adipate, diisodecyl adipate, derivatives thereof, or combinations thereof. In some embodiments, the plasticizer comprises sebacate, including dibutyl sebacate (DBS), bis(2-ethylhexyl) sebacate, diethyl sebacate, dimethyl sebacate, derivatives thereof, or combinations thereof. In some embodiments, the plasticizer comprises maleate, including bis(2-ethylhexyl) maleate, dibutyl maleate, diisobutyl maleate, derivatives thereof, or combinations thereof.In some embodiments, the plasticizer comprises a bio-based plasticizer, including acetylated monoglyceride, alkyl citrate, methyl ricinoleate, or a green plasticizer. In some embodiments, the alkyl citrate is selected from the group consisting of: triethyl citrate, acetylated triethyl citrate, tributyl citrate, acetylated tributyl citrate, trioctyl citrate, acetylated trioctyl citrate, trihexyl citrate, acetylated trihexyl citrate, butyryl trihexylcitrate, trimethyl citrate, derivatives thereof, or combinations thereof. In some embodiments, the green plasticizer is selected from the group consisting of: epoxidized soybean oil, epoxidized vegetable oil, epoxidized esters of soybean oil, derivatives thereof, or combinations thereof. In some embodiments, the plasticizer includes azelaic acid esters, benzoic acid esters (e.g., sucrose benzoate), terephthalate esters (e.g., dioctyl terephthalate), diisononyl 1,2-cyclohexanedicarboxylate, alkyl sulfonates, sulfonamides (e.g., N-ethyltoluenesulfonamide, N-(2-hydroxypropyl)benzenesulfonamide, N-(n-butyl)benzenesulfonamide), organophosphates (e.g., tricresyl phosphate or tributyl phosphate), ethylene glycol (e.g., triethylene glycol dihexanoate or tetraethylene glycol diheptate), polyethers, polymeric plasticizers, polybutene, derivatives thereof, or combinations thereof.

[0277] In some embodiments, the printable resin includes a solvent. In some embodiments, the solvent includes a nonpolar solvent. In some embodiments, the nonpolar solvent includes pentane, cyclopentane, hexane, cyclohexane, benzene, toluene, 1,4-dioxane, chloroform, diethyl ether, dichloromethane, derivatives thereof, or combinations thereof. In some embodiments, the solvent includes a polar aprotic solvent. In some embodiments, the polar aprotic solvent includes tetrahydrofuran, ethyl acetate, acetone, dimethylformamide, acetonitrile, DMSO, propylene carbonate, derivatives thereof, or combinations thereof. In some embodiments, the solvent includes a polar protic solvent. In some embodiments, the polar protic solvent includes formic acid, n-butanol, isopropanol, n-propanol, tert-butanol, ethanol, methanol, acetic acid, water, derivatives thereof, or combinations thereof.

[0278] In some embodiments, the printable resin includes biologically significant chemicals. In some embodiments, biologically significant chemicals include hormones, enzymes, active pharmaceutical ingredients, antibodies, proteins, drugs, or any combination thereof. In some embodiments, biologically significant chemicals include pharmaceutical compositions, chemicals, genes, peptides, enzymes, biomarkers, dyes, compliance indicators, antibiotics, analgesics, medical-grade drugs, chemical reagents, bioactive agents, antibacterial agents, antibiotics, anti-inflammatory agents, immunosuppressants, immunostimulants, dentin desensitizers, odor masking agents, immunomodulators, anesthetics, nutrients, antioxidants, lipopolysaccharide chelating agents, or peroxides.

[0279] In some embodiments, the added components (i.e., thermal initiators, polymerization catalysts, polymerization inhibitors, light blockers, plasticizers, solvents, surface energy modifiers, pigments, dyes, fillers, or biologically significant chemicals) are functionalized to allow them to bind into the polymer network, making them difficult to extract from the final cured material. In some embodiments, thermal initiators, polymerization catalysts, polymerization inhibitors, light blockers, plasticizers, surface energy modifiers, pigments, dyes, and / or fillers are functionalized to promote their binding into the cured polymer material. As used herein, a polymer network can refer to a polymer composition comprising multiple polymer chains, wherein a majority (e.g., ≥80%) and optionally all polymer chains are interconnected to form a single polymer composition. In embodiments, radiopaque polymers in the form of crosslinked networks are provided, wherein at least some crosslinks of the network structure are formed by covalent bonds.

[0280] In some embodiments, the polymeric material formed from the resin has a low level of extractable material (e.g., unreacted monomers from the photocurable resin). The amount of extractable material can be determined by the weight loss of the polymeric material after soaking in water for 1 week, after soaking in ethanol for 48 hours, or after soaking in hexane for 48 hours. A general experiment for determining the amount of extractable material includes the following steps: (i) weighing a dried sample of the polymeric material; (ii) immersing the sample in a solvent at a given temperature (e.g., 25°C) for a period of time; (iii) refreshing the solvent until extraction is complete; (iv) drying the sample in an oven; (v) weighing the extracted sample; and (vi) calculating the weight loss. In some embodiments, the polymeric material formed from the resin has less than 5 wt%, less than 4 wt%, less than 3 wt%, less than 2 wt%, less than 1 wt%, less than 0.75 wt%, less than 0.5 wt%, or less than 0.25 wt% of extractable material.

[0281] Methods for manufacturing polymer materials

[0282] In some embodiments, this disclosure provides a method for producing the polymeric material described herein from a printable resin as further described herein. In some embodiments, the method includes the following steps:

[0283] Provide printable resins as further disclosed herein; and

[0284] The method involves curing a printable resin, which includes exposing it to light to form a cured polymer material. In some embodiments, the method further includes the step of manufacturing a device using an additive manufacturing apparatus, wherein the additive manufacturing apparatus facilitates curing. In some embodiments, the curing of the printable resin produces a polymer material. In some embodiments, the printable resin is cured using an additive manufacturing apparatus to produce a polymer material. In some embodiments, the method further includes the step of cleaning the polymer material. In some embodiments, cleaning the polymer material includes washing and / or rinsing the polymer material with a solvent, which can remove monomers and unwanted impurities from the polymer material.

[0285] In some embodiments, the methods disclosed herein are part of a photopolymerization process based on high-temperature photolithography. In other embodiments, the methods disclosed herein are part of a solid-state cold polymerization process. In other embodiments, both solid-state thermolithography and cold polymerization are used to manufacture materials or print parts. Cold polymerization refers to the fact that the cured resin does not flow during its polymerization (e.g., below the resin melting temperature, below the shear stress required to induce flow, and / or within the time range during which the resin is being processed and prepared for polymerization).

[0286] Photopolymerization occurs when a suitable formulation (e.g., the printable resin disclosed herein) is exposed to irradiation (e.g., UV or visible light) with sufficient power and a wavelength capable of initiating polymerization. The wavelength and / or power of the irradiation that can be used to initiate polymerization may depend on the photoinitiator used. As used herein, “light” includes any wavelength and power capable of initiating polymerization. Some wavelengths of light include ultraviolet (UV), visible, or infrared light. UV light sources include UVA (wavelengths from about 400 nanometers (nm) to about 320 nanometers), UVB (wavelengths from about 320 nanometers to about 290 nanometers), or UVC (wavelengths from about 290 nanometers to about 100 nanometers). Any suitable source can be used, including laser sources. The source can be broadband or narrowband, or a combination thereof. During the process, the light source can provide continuous light, pulsed light, or both continuous and pulsed light. Both the duration and intensity of the system’s exposure to light can be varied to determine the ideal reaction conditions.

[0287] In some embodiments, the methods disclosed herein use additive manufacturing to produce apparatus comprising the polymeric materials and / or polymeric composites disclosed herein. In some embodiments, the methods disclosed herein use additive manufacturing to produce apparatus substantially composed of the polymeric materials described herein. As further described herein, processes and systems for additive manufacturing are provided. Additive manufacturing includes various techniques that manufacture three-dimensional objects directly from digital models via additive processes. In some aspects, continuous layers of material are deposited and “cured in situ.” Various techniques for additive manufacturing are known in the art, including selective laser sintering (SLS), fused deposition modeling (FDM), and jetting or extrusion. In many embodiments, selective laser sintering involves selectively melting and fused layers of powdered material according to a desired cross-sectional shape using a laser beam to construct an object geometry. In many embodiments, fused deposition modeling involves melting and selectively depositing filaments of a thermoplastic polymer in a layer-by-layer manner to form an object. In yet another example, 3D printing can be used to manufacture the apparatus described herein. In many embodiments, 3D printing involves jetting or extruding one or more materials (e.g., the resins disclosed herein) onto a build surface to form continuous layers of an object geometry. In some embodiments, the resins described herein can be used for inkjet or coating applications. Polymer materials can also be manufactured using a "bucket" process, in which a bucket or reservoir of a curable resin (e.g., the resins disclosed herein) is selectively cured using light. Each layer of curable resin can be selectively exposed in a single exposure or by scanning the entire layer with a beam of light. Specific techniques include stereolithography (SLA), digital light processing (DLP), holographic projection, and two-photon induced photopolymerization (TPIP).

[0288] In some embodiments, the methods disclosed herein use continuous direct manufacturing to produce apparatus comprising polymeric materials. In some embodiments, the methods disclosed herein use continuous direct manufacturing to produce apparatus substantially composed of polymeric materials. Non-limiting exemplary direct manufacturing processes can achieve continuous construction of object geometry by continuously moving a build platform (e.g., along a vertical or Z-direction) during an irradiation phase, such that the curing depth of the irradiated photopolymer (e.g., the curing of irradiated resin during the formation of the polymeric material) is controlled by the movement speed. Therefore, continuous polymerization of materials (e.g., resin polymerization into polymeric materials) can be achieved on the build surface. Such methods are described in U.S. Patent Nos. 7,892,474 and 10,162,264, the disclosures of which are incorporated herein by reference in their entirety. In yet another example, the continuous direct manufacturing method utilizes a “spiral lithography” method, in which a liquid resin (e.g., a printable resin) is cured using focused irradiation while the build platform is continuously rotated and raised. Therefore, object geometry can be continuously constructed along a spiral build path. Such methods are described in U.S. Patent Publication No. 2014 / 0265034, the disclosure of which is incorporated herein by reference in its entirety. Continuous liquid interface production of 3D objects has also been reported (J. Tumbleston et al., Science, 2015, 347(6228), pp. 1349-1352), which is incorporated herein by reference in its entirety for the purpose of describing that process. Another example of a continuous direct manufacturing method may involve extruding a material consisting of a polymer material surrounding a solid strand. The material can be extruded along a continuous three-dimensional path to form an object. Such methods are described in U.S. Patent Publication No. 2014 / 0061974, the disclosure of which is incorporated herein by reference in its entirety.

[0289] In some embodiments, the methods disclosed herein use high-temperature photolithography to produce devices comprising polymeric materials. In some embodiments, the methods disclosed herein use high-temperature photolithography to produce devices substantially composed of polymeric materials. As used herein, “high-temperature photolithography” can refer to any photolithography-based photopolymerization process involving heating one or more photopolymerizable materials (e.g., the curable resins disclosed herein). Heating can reduce the viscosity of one or more photopolymerizable materials before and / or during curing. Non-limiting examples of high-temperature photolithography processes include those described in WO2015 / 075094, WO2016 / 078838, and WO2018 / 032022. In some embodiments, high-temperature photolithography can involve applying heat to the material to maintain a temperature between 50°C and 120°C (e.g., 90°C to 120°C, 100°C to 120°C, 105°C to 115°C, 108°C to 110°C, etc.). The material may be heated to temperatures above 120°C. Note that other ranges may be used without departing from the scope and spirit of the inventive concept described herein.

[0290] In another embodiment, the method disclosed herein includes a continuous direct manufacturing step. The continuous direct manufacturing step may involve extruding a material consisting of a curable liquid material (e.g., a printable resin) surrounding a solid strand. The liquid material may be extruded along a continuous three-dimensional path to form an object or device. Such methods are described in U.S. Patent Publication No. 2014 / 0061974, the disclosure of which is incorporated herein by reference in its entirety.

[0291] In some embodiments, the methods disclosed herein further include manufacturing an object using polymer materials. In some embodiments, manufacturing the object includes additive manufacturing. In some embodiments, manufacturing an object using polymer materials includes printing using a 3D printer. In some embodiments, manufacturing an object using polymer materials includes digital light projection. In some embodiments, manufacturing an object using polymer materials includes using thermolithography.

[0292] In some embodiments, the object is an orthodontic appliance. In some embodiments, the orthodontic appliance is an appliance, expander, or spacer. In some embodiments, the orthodontic appliance includes a plurality of tooth-receiving cavities configured to reposition teeth from a first form to a second form. In some embodiments, the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial form to a target form. In some embodiments, the orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial form to a target form according to a treatment plan. In some embodiments, the orthodontic appliance is an appliance.

[0293] Devices including the polymer materials disclosed herein

[0294] In some embodiments, this disclosure provides devices comprising polymeric materials produced from printable resins as further described herein. In some embodiments, this disclosure provides devices formed by processes and systems further described herein. In some embodiments, the contents of this disclosure are used to create devices intended for placement within a person's oral cavity. For example, such devices may be orthodontic appliances that help move teeth into new positions. In some embodiments, the device may be a retainer that helps prevent teeth from moving into new positions. In some embodiments, the device may be used to expand the palate, move the position of the jaw, or prevent a person from snoring.

[0295] In some embodiments, this disclosure provides a method for producing the apparatus described herein, the apparatus comprising a polymer material. In some embodiments, the method includes a step of shaping a printable resin into a desired shape prior to a step of curing the printable resin, thereby producing a polymer material having said desired shape. In some embodiments, the method includes a step of shaping a printable resin into a desired shape during a step of curing the printable resin, thereby producing a polymer material having said desired shape. In some embodiments, the method includes a step of curing the printable resin to form a polymer material, and then shaping the polymer material into a desired shape. In some embodiments, the desired shape is an orthodontic device. In some embodiments, the desired shape is an apparatus and / or object disclosed herein. In some embodiments, the material disclosed herein is a shape memory material.

[0296] Exemplary embodiments of devices that can be cured using the materials disclosed herein include dental instruments for humans. In some embodiments, such devices can be used as treatment systems for providing orthodontic treatment. In some embodiments, the materials and methods described herein can be used in, for example, the automotive industry, aerospace industry, spare parts industry, hobbyist industry, footwear industry, and shipbuilding industry. In some embodiments, the materials and methods described herein can be used to print replacement parts for other devices and / or equipment.

[0297] In some aspects, this disclosure provides a method for manufacturing orthodontic devices comprising a polymeric material as described herein, the method comprising: providing a printable resin as further described herein; and manufacturing the polymeric material via a direct manufacturing process or an additive manufacturing process. The printable resin may be exposed to light during the direct manufacturing process or the additive manufacturing process. The process may also include an additional curing step following the manufacture of the polymeric material.

[0298] In some aspects, this disclosure provides orthodontic appliances comprising polymeric materials as further described herein. The orthodontic appliance may be an appliance, expander, or spacer. In some embodiments, the orthodontic appliance includes a plurality of tooth-receiving cavities configured to reposition teeth from a primary configuration to a secondary configuration. In some embodiments, the orthodontic appliance is one of a plurality of orthodontic appliances configured to optionally reposition teeth from an initial configuration to a target configuration according to a treatment plan. As used herein, “multiple teeth” includes two or more teeth.

[0299] In many embodiments, one or more posterior teeth include one or more of molars, premolars, or canines, and one or more anterior teeth include one or more of central incisors, lateral incisors, canines, first premolars, or first premolars.

[0300] The curable resins and curable polymer materials disclosed herein exhibit advantageous thermomechanical properties for use as orthodontic instruments, for example, for moving one or more teeth.

[0301] The embodiments disclosed herein can be used to couple one or more groups of teeth to each other. A group of teeth may include a first group of one or more anterior teeth and a second group of one or more posterior teeth. The first group of teeth can be coupled to the second group of teeth using the polymer-shell instrument disclosed herein.

[0302] The embodiments disclosed herein are well suited for moving one or more teeth in a first group or moving one or more teeth in a second group, as well as combinations thereof.

[0303] The embodiments disclosed herein are well-suited for use with one or more commercially available tooth movement components (e.g., attachments and polymer-cased instruments). In many embodiments, the instrument and one or more attachments are configured to move one or more teeth along a tooth movement vector comprising six degrees of freedom (three of which are rotational and three of which are translational).

[0304] This disclosure provides orthodontic systems and related methods for designing and providing improved or more effective tooth movement systems to induce desired tooth movement and / or reposition teeth into a desired alignment.

[0305] While references have been made to devices including polymer-shelled instruments, the embodiments disclosed herein are well-suited for use with a variety of dental instruments, including those without one or more polymers or shells. The instrument can be made from one or more of a variety of materials, such as metals, glass, reinforcing fibers, carbon fibers, composites, reinforced composites, aluminum, biomaterials, and combinations thereof. In some cases, the reinforcing composite may comprise a polymer matrix reinforced, for example, by ceramic or metal particles. The instrument can be shaped in various ways, such as by thermoforming or direct manufacturing as described herein. Alternatively or in combination, the instrument can be manufactured using machining, such as by computer numerical control machining of instruments made from blocks of material. Preferably, the instrument is manufactured using a curable resin according to this disclosure.

[0306] Now turn to the accompanying drawings, where the same reference numerals denote the same elements in each figure. Figure 1AAn exemplary tooth repositioning device or appliance (100) is illustrated, which can be worn by a patient to achieve incremental repositioning of individual teeth (102) in the jaw, and comprises a cured polymer material disclosed herein. The device may include a housing (e.g., a continuous polymer housing or a segmented housing) having a tooth-receiving cavity that accommodates and resiliently repositions the teeth. The device or one or more portions thereof may be fabricated indirectly using a physical model of a tooth. For example, an device (e.g., a polymer device) may be formed using a physical model of a tooth and sheets of polymer material of appropriate number of layers. In some embodiments, the physical device is fabricated directly from a digital model of the device, for example, using rapid prototyping techniques. The device may be adapted to all or fewer teeth present in the maxilla or mandible. The device may be specifically designed to accommodate a patient's teeth (e.g., the morphology of the tooth-receiving cavity matches the morphology of the patient's teeth), and the device may be fabricated based on a positive or negative model of the patient's teeth generated by molding, scanning, etc. Optionally, the instrument may be a general-purpose instrument configured to receive teeth, but need not be shaped to match the morphology of the patient's teeth. In some cases, only certain teeth received by the instrument may be repositioned by the instrument, while other teeth may provide a base or anchoring area to hold the instrument in place when the instrument applies force to one or more teeth to be repositioned. In some cases, some, most, or even all of the teeth may be repositioned at some point during treatment. The moved teeth may also serve as a base or anchor point to hold the instrument in place while the patient wears it. Typically, no wires or other devices are provided to hold the instrument in place on the teeth. However, in some cases, it may be necessary or required to provide separate attachments or other anchoring elements (104) on the teeth (102) and corresponding receptacles or orifices (106) in the instrument (100) so that the instrument can apply selected forces on the teeth. Example instruments (including The instruments used in the system have been described in numerous patents and patent applications assigned to Align Technology, including, for example, U.S. Patent Nos. 6,450,807 and 5,975,893, and on the company’s website, which is accessible on the Internet (see, for example, the URL “invisalign.com”). Examples of dental attachments suitable for use with orthodontic instruments are also described in the patents and patent applications assigned to Align Technology, including, for example, U.S. Patent Nos. 6,309,215 and 6,830,450.

[0307] Figure 1BA tooth repositioning system (110) comprising multiple instruments (112), (114), and (116) is shown. Any instrument described herein may be designed and / or provided as part of a set of multiple instruments for use in a tooth repositioning system. Each instrument may be configured such that the tooth receiving cavity has a geometry corresponding to the intermediate or final tooth arrangement intended for use with the instrument. By placing a series of incremental position-adjusting instruments on the patient's teeth, the patient's teeth can be progressively repositioned from an initial tooth arrangement to a target tooth arrangement. For example, the tooth repositioning system (110) may include a first instrument (112) corresponding to the initial tooth arrangement, one or more intermediate instruments (114) corresponding to one or more intermediate arrangements, and a final instrument (116) corresponding to the target arrangement. The target tooth arrangement may be the planned final tooth arrangement selected for the patient's teeth at the end of all planned orthodontic treatment. Alternatively, the target alignment can be one of several intermediate alignments of the patient's teeth during orthodontic treatment, which may include a variety of different treatment options, including but not limited to: recommendations for surgery, suitability for interproximal enamel reduction (IPR), scheduling of progress checks, optimization of anchor point positions, desired jaw expansion, and involvement of restorative dentistry (e.g., inlays, onlays, crowns, bridges, implants, veneers, etc.). Thus, it can be understood that the target tooth alignment can be the result of any planned alignment of the patient's teeth following one or more incremental repositioning phases. Similarly, the initial tooth alignment can be any initial alignment of the patient's teeth followed by one or more incremental repositioning phases.

[0308] Figure 1CA method (150) for orthodontic treatment using multiple instruments according to an embodiment is illustrated. Method (150) can be practiced using any of the instruments or groups of instruments described herein. In step (160), a first orthodontic instrument is applied to the patient's teeth to reposition the teeth from a first dental alignment to a second dental alignment. In step (170), a second orthodontic instrument is applied to the patient's teeth to reposition the teeth from the second dental alignment to a third dental alignment. Any suitable number of ordered appliances and any suitable combination of ordered appliances can be used to repeat method (150) as needed to progressively reposition the patient's teeth from the initial alignment to the target alignment. The instruments can be manufactured all at once in the same phase, or in groups or batches (e.g., at the beginning of treatment), or the instruments can be manufactured all at once, and the patient can wear each instrument until no pressure is felt on the teeth from each instrument, or until the maximum amount of tooth movement exhibited for that given phase has been reached. The multiple instruments can be designed and even manufactured before the patient wears any of the multiple different instruments (e.g., a group). After wearing the appliance for an appropriate period of time, the patient can replace the current appliance with the next appliance in the series until no appliances remain. These appliances are typically not attached to the teeth, and the patient can install and replace the appliance at any time during the procedure (e.g., patient-removable appliances). The final appliance or some appliances in the series may have one or more geometries selected for overcorrection of the tooth alignment. For example, one or more appliances may have geometries that will allow the movement of each tooth beyond the tooth alignment selected as "final" (if fully achieved). Such overcorrection may be desirable to counteract potential relapse after the repositioning method has ended (e.g., allowing the teeth to move back towards their pre-correction positions). Overcorrection can also be beneficial to accelerate the orthodontic process (e.g., appliances with geometries positioned beyond the desired intermediate or final position can move the teeth towards that position more quickly). In this case, the use of the appliance can be stopped before the teeth reach the position defined by the appliance. Furthermore, overcorrection can be intentionally applied to compensate for any inaccuracies or limitations of the appliance.

[0309] The various embodiments of orthodontic appliances presented herein can be manufactured in a wide variety of ways. In some embodiments, the orthodontic appliances (or portions thereof) described herein can be produced using direct manufacturing techniques, such as additive manufacturing (also referred to herein as “3D printing”) or subtractive manufacturing techniques (e.g., milling). In some embodiments, direct manufacturing involves forming an object (e.g., an orthodontic appliance or a portion thereof) without using physical templates (e.g., molds, masks, etc.) to define the object's geometry. Additive manufacturing technologies can be categorized as follows: (1) vat photopolymerization (e.g., stereolithography), in which objects are constructed layer by layer from a barrel of liquid photopolymer resin; (2) material spraying, in which materials are sprayed onto a build platform using a continuous or on-demand dripping (DOD) method; (3) binder spraying, in which alternating layers of build material (e.g., powder-based materials) and binder material (e.g., liquid binder) are deposited through a printhead; (4) fused deposition modeling (FDM), in which materials are extracted through a nozzle, heated, and deposited layer by layer; (5) powder bed fusion, including but not limited to direct metal laser sintering (DMLS), electron beam melting (EBM), selective thermal sintering (SHS), selective laser melting (SLM), and selective laser sintering (SLS); (6) sheet lamination, including but not limited to layered solid fabrication (LOM) and ultrasonic additive manufacturing (UAM); and (7) directional energy deposition, including but not limited to laser engineered mesh forming, directional light fabrication, direct metal deposition, and 3D laser cladding. For example, stereolithography can be used to directly manufacture one or more of the instruments described herein. In some embodiments, stereolithography involves selectively polymerizing a photosensitive resin (e.g., a photopolymer) using light (e.g., ultraviolet light) according to a desired cross-sectional shape. By sequentially polymerizing multiple object cross-sections, the object geometry can be built up in a layer-by-layer manner.

[0310] In some embodiments, the direct manufacturing methods provided herein build up the geometry of an object in a layer-by-layer manner, wherein successive layers are formed in discrete build-up steps. Alternatively or in combination, direct manufacturing methods that allow for the continuous building up of the object's geometry may be used, referred to herein as "continuous direct manufacturing." Various types of continuous direct manufacturing methods can be used. As an example, in some embodiments, the apparatus of this invention is manufactured using "continuous liquid phase printing," in which the object is continuously built from a reservoir of photopolymerizable resin by forming a gradient of partially cured resin between the build surface of the object and a "dead zone" that inhibits polymerization. In some embodiments, a semi-permeable membrane is used to control the delivery of photopolymerization inhibitors (e.g., oxygen) into the dead zone to form a polymerization gradient. Continuous liquid phase printing can achieve manufacturing speeds approximately 25 to approximately 100 times faster than other direct manufacturing methods, and can achieve speeds approximately 1000 times faster by incorporating a cooling system. Continuous liquid phase printing is described in the following documents: U.S. Patents with publication numbers 2015 / 0097315, 2015 / 0097316 and 2015 / 0102532, the contents of each of which are incorporated herein by reference in their entirety.

[0311] As another example, continuous direct manufacturing methods can achieve continuous construction of object geometry through the continuous movement of the construction platform during the irradiation phase (e.g., along the vertical or Z-direction), thereby controlling the hardening depth of the irradiated photopolymer with the speed of movement. Thus, continuous polymerization of the material on the construction surface can be achieved. Such methods are described in U.S. Patent No. 7,892,474, the disclosure of which is incorporated herein by reference in its entirety.

[0312] In another example, a continuous direct manufacturing method may involve extruding a composite material consisting of a curable liquid material surrounding a solid strand. The composite material can be extruded along a continuous three-dimensional path to form an object. Such methods are described in U.S. Patent Publication No. 2014 / 0061974, the disclosure of which is incorporated herein by reference in its entirety.

[0313] In yet another example, the continuous direct manufacturing method utilizes heliolithography, in which a liquid photopolymer is cured using focused irradiation while the build platform is continuously rotated and raised. Thus, the geometry of an object can be continuously built along a helical construction path. Examples of such methods are described in U.S. Patent Publication No. 2014 / 0265034, the disclosure of which is incorporated herein by reference in its entirety.

[0314] Machine parameters may include curing parameters. For digital light processing (DLP) based curing systems, curing parameters may include light intensity, curing time, amount of material added by a funnel, sprayer, and / or inkjet printer, light intensity and dose at a second wavelength (e.g., infrared light), and / or grayscale of all (or more) images. For laser-based curing systems, curing parameters may include light intensity, scanning speed, beam size, beam shape, and / or beam power distribution. These machine parameters (e.g., certain parameters per 1-x layers and certain parameters after each build) may be periodically monitored and adjusted as part of process control on the manufacturing machine. Process control can be achieved by including sensors on the machine that measure power and other beam parameters per layer or every few seconds and automatically adjust them via feedback loops. For DLP machines, grayscale may be measured and calibrated before, during, and / or at the end of each build and / or at predetermined time intervals (e.g., every n builds, once per hour, once per day, once per week, etc.), depending on system stability. Furthermore, material properties and / or optical properties can be provided to the manufacturing machine, and the machine's process control module can use these parameters to adjust machine parameters (e.g., light intensity, curing time, grayscale, etc.) to compensate for variations in material properties. By implementing process control on the manufacturing machine, variations in instrument precision and residual stress can be reduced.

[0315] Direct manufacturing offers various advantages compared to other manufacturing methods. For example, in contrast to indirect manufacturing, direct manufacturing allows for the production of orthodontic devices without the use of any molds or templates to shape the device, thereby reducing the number of manufacturing steps involved and improving the resolution and accuracy of the final device geometry. Additionally, direct manufacturing allows for precise control over the three-dimensional geometry of the device, such as its thickness. Complex structures and / or auxiliary components can be integrally formed as a monolith with the device housing in a single manufacturing step, rather than being added to the housing in separate manufacturing steps. In some embodiments, direct manufacturing is used to produce device geometries that are difficult to create using alternative manufacturing techniques, such as devices with very small or fine features, complex geometries, undercuts, adjacent structures, and housings with variable thickness and / or internal structures (e.g., increasing strength by reducing weight and material usage). For example, in some embodiments, the direct manufacturing method described herein allows for the manufacture of orthodontic devices with feature dimensions less than or equal to about 5 μm, or in the range of about 5 μm to about 50 μm, or in the range of about 20 μm to about 50 μm.

[0316] The direct manufacturing techniques described herein can be used to produce devices having substantially isotropic material properties (e.g., substantially the same or similar strength in all directions). In some embodiments, the direct manufacturing methods described herein allow the production of orthodontic devices with strength varying by no more than about 25%, about 20%, about 15%, about 10%, about 5%, about 1%, or about 0.5% in all directions. In some embodiments, the direct manufacturing techniques described herein can be used to produce devices having substantially anisotropic material properties (e.g., substantially different strength in all directions). In some embodiments, the direct manufacturing techniques described herein can produce orthodontic devices with strength varying in a controlled manner by more than 10%, more than 15%, more than 20%, or more than 25% in all directions. Furthermore, the direct manufacturing methods described herein can be used to manufacture orthodontic devices at a faster rate compared to other manufacturing techniques. In some embodiments, the direct manufacturing method described herein allows for the production of orthodontic instruments within time intervals of less than or equal to approximately 12 hours, approximately 8 hours, approximately 4 hours, approximately 2 hours, approximately 1 hour, approximately 30 minutes, approximately 25 minutes, approximately 20 minutes, approximately 15 minutes, approximately 10 minutes, approximately 5 minutes, approximately 4 minutes, approximately 3 minutes, approximately 2 minutes, approximately 1 minute, or approximately 30 seconds (optionally including time for any removal of supports, post-curing of components, and / or removal of uncured resin, if any of these steps are required). Such manufacturing speed allows for rapid “chairside” production of custom instruments, for example, during regular appointments or checkups.

[0317] In some embodiments, the direct manufacturing methods described herein implement process control over various machine parameters for the direct manufacturing system or apparatus to ensure that the resulting instruments are manufactured with a high degree of precision. Such precision is advantageous for ensuring that the desired force system is accurately delivered to the teeth to effectively induce tooth movement. Process control can be implemented to account for process variations caused by a variety of sources, such as material properties, machine parameters, environmental variables, and / or post-processing parameters.

[0318] Material properties can vary depending on the characteristics of the raw materials, their purity, and / or process variables during mixing. In many embodiments, resins or other materials intended for direct manufacturing should be manufactured under strict process control to ensure minimal variation in optical properties, material properties (e.g., viscosity, surface tension), physical properties (e.g., modulus, strength, elongation), and / or thermal properties (e.g., glass transition temperature, heat distortion temperature). Process control for material manufacturing processes can be achieved by screening the physical properties of raw materials during mixing and / or controlling temperature, humidity, and / or other process parameters. By implementing process control over the material manufacturing process, variability in process parameters can be reduced, resulting in more uniform material properties for each batch. As further discussed herein, residual variations in material properties can be compensated for through on-machine process control.

[0319] In many embodiments, environmental variables (e.g., temperature, humidity, sunlight, or exposure to other energy / curing sources) are kept within a narrow range to reduce variations in instrument thickness and / or other properties. Optionally, machine parameters may be adjusted to compensate for environmental variables.

[0320] In many embodiments, post-processing of the instrument includes cleaning, post-curing, and / or support removal processes. Relevant post-processing parameters may include the purity of the cleaning agent, cleaning pressure and / or temperature, cleaning time, post-curing energy and / or time, and / or the consistency of the support removal process. These parameters can be measured and adjusted as part of a process control scheme. Furthermore, the physical properties of the instrument can be altered by modifying post-processing parameters. Adjusting post-processing machine parameters can provide another way to compensate for changes in material properties and / or machine properties.

[0321] The configuration of orthodontic appliances described herein can be determined based on the patient's treatment plan (e.g., a treatment plan involving the sequential application of multiple appliances to incrementally reposition teeth). Computer-based treatment planning and / or appliance manufacturing methods can be used to facilitate the design and manufacture of the appliances. For example, one or more appliance components described herein can be digitally designed and manufactured using computer-controlled manufacturing equipment (e.g., computer numerical control (CNC) milling, computer-controlled rapid prototyping (e.g., 3D printing), etc.). The computer-based methods proposed herein can improve the accuracy, flexibility, and convenience of appliance manufacturing.

[0322] Figure 2 A method (200) for designing orthodontic instruments to be manufactured by direct manufacturing, according to an embodiment, is shown. The method (200) can be applied to any embodiment of the orthodontic instruments described herein. Some or all of the steps of the method (200) can be performed by any suitable data processing system or apparatus (e.g., one or more processors configured with suitable instructions).

[0323] In step (210), a movement path is determined to move one or more teeth from an initial arrangement to a target arrangement. The initial arrangement can be determined by a mold or a scan of the patient's teeth or oral tissues, such as using wax bite, direct contact scanning, X-ray imaging, tomography, ultrasound imaging, and other techniques for acquiring information about the location and structure of teeth, jaws, gingiva, and other orthodontic-related tissues. From the acquired data, a digital dataset representing the initial (e.g., preprocessed) arrangement of the patient's teeth and other tissues can be derived. Optionally, the initial digital dataset is processed to segment the tissue components to each other. For example, a data structure digitally representing the individual crowns can be generated. Advantageously, a digital model of the entire tooth can be generated, including measured or extrapolated hidden surfaces and root structures, as well as the surrounding bone and soft tissues.

[0324] The target alignment of teeth (e.g., the desired and expected end result of orthodontic treatment) can be received from the clinician in the form of a prescription, calculated based on the fundamental principles of orthodontics, and / or calculated from an outpatient prescription. By specifying the desired final position of the teeth and a digital representation of the teeth themselves, the final position and surface geometry of each tooth can be specified to form a complete model of the tooth alignment at the end of the desired treatment.

[0325] With both the initial and target positions for each tooth, a movement path can be defined for the movement of each tooth. In some embodiments, the movement path is configured to move the tooth in the fastest manner with the fewest round trips to bring the tooth from its initial position to its desired target position. Optionally, the tooth path can be segmented, and the segments can be calculated such that the movement of each tooth within a segment remains within thresholds of linearity and rotational translation. In this way, the endpoints of each path segment can constitute a clinically feasible repositioning, and the set of segment endpoints can constitute a clinically feasible sequence of tooth positions, so that moving from one point in the sequence to the next does not result in tooth conflict.

[0326] In step (220), a force system is determined to generate the movement of one or more teeth along the movement path. The force system may include one or more forces and / or one or more torques. Different force systems result in different types of tooth movement, such as tilting, translation, rotation, squeezing, intrusion, root movement, etc. Biomechanical principles, modeling techniques, force calculation / measurement techniques, etc. (including knowledge and methods commonly used in orthodontic treatment) can be used to determine the appropriate force system to be applied to the teeth to accomplish the tooth movement. Sources may be considered when determining the force system to be applied, including literature, force systems determined through experimental or virtual modeling, computer-based modeling, clinical experience, minimization of unwanted forces, etc.

[0327] Determining the force system can include constraints on permissible forces, such as permissible direction and amplitude, and the desired movement induced by the applied forces. For example, different movement strategies may be required for different patients when fabricating a palatal expander. For instance, because very young patients may not have fully-formed sutures, the amount of force required to separate the palate may depend on the patient's age. Therefore, in juvenile patients without fully closed palatal sutures and other patients, palatal expansion can be achieved with smaller force amplitudes. Slow palatal movement can also facilitate bone growth to fill the expanding sutures. For other patients, faster expansion may be required, which can be achieved by applying greater forces. These requirements can be combined as needed to select the structure and materials of the instrument; for example, by selecting a palatal expander capable of applying greater forces to break the mid-palatal suture and / or induce rapid palatal expansion. Subsequent instrumentation stages can be designed to apply varying amounts of force, for example, initially applying greater forces to break the sutures, followed by smaller forces to maintain suture separation or gradually expand the palate and / or dental arch.

[0328] Determining the force system may also involve modeling the patient's facial structures, such as the skeletal structure of the jaw and palate. For example, scan data of the palate and dental arch (e.g., X-ray data or 3D optical scan data) can be used to determine parameters of the skeletal and muscular systems of the patient's oral cavity, thereby determining sufficient force to provide the desired palatal and / or dental arch expansion. In some embodiments, the thickness and / or density of the palatal suture can be measured or input by a treatment specialist. In other embodiments, the treatment professional can select appropriate treatment based on the patient's physiological characteristics. For example, palatal characteristics can also be assessed based on factors such as the patient's age—for instance, younger adolescent patients typically require less force to expand the sutures than older patients because the sutures have not yet fully formed.

[0329] In step (230), the design of an arch or palatal expander for an orthodontic appliance configured to generate a force system is determined. The determination of the arch or palatal expander design, the appliance's geometry, material composition, and / or properties can be performed using a treatment or force application simulation environment. The simulation environment may include, for example, a computer modeling system, a biomechanical system, or a device. Optionally, a digital model of the appliance and / or teeth, such as a finite element model, can be generated. Finite element models can be created using computer program application software from various vendors. To create a solid geometry model, computer-aided engineering (CAE) or computer-aided design (CAD) programs, such as those available from Autodesk, San Rafael, California, can be used. Software products. To create and analyze finite element models, many vendors' software products can be used, including ANSYS finite element analysis software packages from Canonsburg, Pennsylvania, and Dassault Systèmes' SIMULIA (Abaqus) software products from Waltham, Massachusetts.

[0330] Optionally, one or more dental arch or palatal expander designs can be selected for testing or force modeling. As described above, the desired tooth movement and the required or desired force system to induce the desired tooth movement can be identified. Using a simulation environment, candidate dental arch or palatal expander designs can be analyzed or modeled to determine the actual force system resulting from the use of the candidate apparatus. Optionally, one or more modifications can be made to the candidate apparatus, and the force model can be further analyzed as described, for example, to iteratively determine the apparatus design that produces the desired force system.

[0331] In step (240), instructions are generated for manufacturing orthodontic appliances incorporating an arch or palatal expander design. These instructions may be configured to control a manufacturing system or apparatus to produce orthodontic appliances with the specified arch or palatal expander design. In some embodiments, the instructions are configured to manufacture the orthodontic appliances using direct manufacturing methods (e.g., stereolithography, selective laser sintering, fused deposition modeling, 3D printing, continuous direct manufacturing, multimaterial direct manufacturing, etc.) according to the various methods presented herein. In alternative embodiments, the instructions may be configured to manufacture the appliances indirectly, for example, by thermoforming.

[0332] Method (200) may include additional steps: 1) intraoral scanning of the patient’s maxillary arch and palate to generate three-dimensional data of the palate and maxillary arch; 2) determining the three-dimensional shape profile of the instrument to provide the gap and occlusal structure as described herein.

[0333] While the steps above illustrate a method (200) for designing orthodontic appliances according to some embodiments, those skilled in the art will recognize some variations based on the teachings described herein. Some steps may include sub-steps. Certain steps may typically be repeated as needed. One or more steps of method (200) can be performed using any suitable manufacturing system or apparatus, such as those described herein. Some steps may be optional, and the order of steps may be changed as needed.

[0334] Figure 3 A method (300) for digitally planning the design or manufacture of orthodontic treatments and / or instruments is illustrated according to embodiments. This method (300) can be applied to any treatment procedure described herein and can be performed by any suitable data processing system.

[0335] In step (310), a digital representation of the patient's teeth is received. This digital representation may include surface topographic data of the patient's oral cavity (including teeth, gingival tissue, etc.). The surface topographic data can be generated by directly scanning the oral cavity, a physical model (positive or negative) of the oral cavity, or an impression of the oral cavity using a suitable scanning device (e.g., a handheld scanner, a desktop scanner, etc.).

[0336] In step (320), one or more treatment phases are generated based on the digital representation of the teeth. A treatment phase can be an incremental repositioning phase of an orthodontic procedure designed to move one or more of the patient's teeth from an initial tooth arrangement to a target arrangement. For example, a treatment phase can be generated by: determining the initial tooth arrangement indicated by the digital representation, determining the target tooth arrangement, and determining the movement path for one or more teeth in the initial arrangement required to achieve the target tooth arrangement. The movement path can be optimized based on minimizing the total distance moved, preventing conflicts between teeth, avoiding more difficult tooth movements, or any other suitable criteria.

[0337] In step (330), at least one orthodontic appliance is manufactured based on the generated treatment phase. For example, a set of appliances may be manufactured, each shaped according to the tooth alignment specified by one of the treatment phases, so that the patient can wear these appliances sequentially to incrementally reposition the teeth from the initial alignment to the target alignment. The appliance set may include one or more orthodontic appliances described herein. The manufacture of the appliances may include creating a digital model of the appliance to be used as input to a computer-controlled manufacturing system. The appliances may be formed using direct manufacturing methods, indirect manufacturing methods, or a combination thereof, as needed.

[0338] In some cases, planning for various arrangements or treatment phases may not be necessary for the design and / or manufacture of the device. For example... Figure 3 As shown by the dashed line, the design and / or manufacture of orthodontic appliances and possible specific orthodontic treatments may include using a representation of the patient's teeth (e.g., receiving a digital representation of the patient's teeth (310)) and then designing / or manufacturing orthodontic appliances based on the representation of the patient's teeth in the arrangement represented by the received representation.

[0339] On-Track Treatment

[0340] In some embodiments, this disclosure provides a method for repositioning a patient's teeth, the method comprising: applying an orthodontic instrument disclosed herein to at least one of the patient's teeth, and moving the at least one of the patient's teeth toward the middle or the last row of teeth.

[0341] In some embodiments, this disclosure provides a method for repositioning a patient's tooth, the method comprising:

[0342] Generate a treatment plan for the patient, which includes multiple intermediate tooth arrangements for moving teeth from the initial arrangement to the final arrangement along the treatment path;

[0343] Production of 3D-printed orthodontic instruments using materials further described herein; and

[0344] Using orthodontic appliances, at least one of the patient's teeth is moved toward the center or until the final tooth alignment is not deviated.

[0345] Reference Figure 4 The process according to this disclosure is illustrated (400). Various aspects of this process will be discussed in further detail below. The process includes: receiving information about the patient's orthodontic status and / or treatment information (402), generating a case assessment (404), and generating a treatment plan for repositioning the patient's teeth (406). In short, the patient / treatment information will include obtaining data including the initial alignment of the patient's teeth, which typically includes obtaining impressions or scans of the patient's teeth prior to the start of treatment, and may also include identifying one or more treatment goals selected by the practitioner and / or the patient. A case assessment (404) may be generated to evaluate the complexity or difficulty of moving specific patient teeth, generally or specifically, in relation to the identified treatment goals, and may also include the practitioner's experience and / or comfort in implementing the desired orthodontic treatment. However, in some cases, the assessment may include simply identifying specific treatment options of concern to the patient and / or the practitioner (e.g., appointment scheduling, progress tracking, etc.). The information and / or corresponding treatment plan will include identifying the desired final or target alignment of the patient's teeth, as well as multiple consecutive or intermediate tooth alignments for moving teeth along the treatment path from the initial alignment to the selected final or target alignment.

[0346] The process also includes generating customized treatment guidelines (408). Treatment plans typically comprise multiple treatment phases, with the generated set of customized treatment guidelines corresponding to the phases of the treatment plan. The guidelines will include detailed information about the timing and / or what needs to be accomplished (e.g., specific tasks) during a given treatment phase and will provide sufficiently detailed guidance to the practitioner throughout the treatment phase, including less experienced practitioners or relatively new practitioners for a particular orthodontic treatment procedure. Because the guidelines are designed specifically to correspond to the treatment plan and provide guidance on activities specifically identified in the treatment information and / or generated treatment plan, they are considered customized. The customized treatment guidelines are then provided to the practitioner to help guide them on how to achieve the given treatment phase. As described above, instruments can be generated based on the arrangement of the plan and provided to the practitioner for eventual administration to the patient (410). Instruments are typically provided and / or administered in sets or batches, such as 2, 3, 4, 5, 6, 7, 8, 9, or more instruments, but are not limited to any particular implementation plan. Instruments can be provided to the practitioner simultaneously with the given set of guidelines, or instruments and guidelines can be provided separately.

[0347] After treatment begins according to the plan and after the application of instruments to the patient, treatment progress is tracked, for example by tooth matching, to assess the current and actual alignment of the patient's teeth compared to the planned alignment (412). If it is determined that the patient's teeth are "not deviating" and are progressing according to the treatment plan, treatment proceeds as planned and progresses to the next treatment phase (414). If the patient's teeth have substantially achieved the initially planned final alignment, treatment progresses to the final phase of treatment (414). If it is determined that the patient's teeth are being tracked according to the treatment plan but have not yet achieved the final alignment, the next set of instruments may be applied to the patient.

[0348] Table 1 below provides threshold differences between the planned and selected actual positions of the teeth to indicate whether the patient's teeth have progressed without deviation. Progression is considered non-deviational if the patient's teeth have progressed at or within the threshold. Progression is considered deviated if the patient's teeth have progressed beyond the threshold.

[0349]

[0350]

[0351]

[0352] Table 1

[0353] By comparing the current position of the teeth with their expected or planned position, and by confirming that the teeth are within the parameter variations disclosed in Table 1, it is determined that the patient's teeth are not misaligned. If the patient's teeth are determined to be not misaligned, treatment can proceed as is currently or as previously planned. For example, one or more follow-up instruments (e.g., the next set of instruments) may be administered to patients determined to have progressed without misalignment, according to the treatment plan. Treatment may progress to a final stage and / or may reach a point in the treatment plan where occlusal matching is repeated to determine whether the patient's teeth have progressed as planned or whether the teeth have misaligned.

[0354] In some embodiments, as further disclosed herein, this disclosure provides a method of treating a patient using a 3D-printed orthodontic appliance. In some embodiments, the method of repositioning a patient's teeth (or, in some embodiments, a single tooth) includes: generating a treatment plan for the patient, the plan including a tooth alignment for moving the teeth along a treatment path from an initial alignment to a final alignment; producing a 3D-printed orthodontic appliance; and using the orthodontic appliance to move at least one of the patient's teeth without deviation toward an intermediate or final alignment. In some embodiments, the 3D-printed orthodontic appliance is produced using a printable resin further disclosed herein. For example, the non-deviation performance can be determined from Table 1 above.

[0355] In some embodiments, the method further includes tracking the progress of the patient's teeth along the treatment path after the application of orthodontic appliances. In some embodiments, tracking includes comparing the current alignment of the patient's teeth with the planned alignment of the teeth. As a non-limiting example, after a period of time (e.g., two weeks) following the initial application of orthodontic appliances, the current alignment of the patient's teeth (i.e., at the two-week treatment interval) can be compared with the planned alignment of the teeth in the treatment plan. In some embodiments, progress can also be tracked by comparing the current alignment of the patient's teeth with the initial configuration of the patient's teeth. The time period can be, for example, greater than 3 days, greater than 4 days, greater than 5 days, greater than 6 days, greater than 7 days, greater than 8 days, greater than 9 days, greater than 10 days, greater than 11 days, greater than 12 days, greater than 13 days, greater than 2 weeks, greater than 3 weeks, greater than 4 weeks, or greater than 2 months. In some embodiments, the time period can be from at least 3 days to at most 4 weeks, from at least 3 days to at most 3 weeks, from at least 3 days to at most 2 weeks, from at least 4 days to at most 4 weeks, from at least 4 days to at most 3 weeks, or from at least 4 days to at most 2 weeks. In some embodiments, this time period can be restarted after the application of a new orthodontic instrument.

[0356] In some embodiments, after a period of time using the orthodontic instruments further disclosed herein, greater than 50%, greater than 55%, greater than 60%, greater than 65%, greater than 70%, greater than 75%, greater than 80%, greater than 85%, greater than 90%, greater than 91%, greater than 92%, greater than 93%, greater than 94%, greater than 95%, greater than 96%, greater than 97%, greater than 98%, or greater than 99% of the patients' teeth do not deviate from the treatment plan. In some embodiments, this time period is 3 days, 4 days, 5 days, 6 days, 7 days, 8 days, 9 days, 10 days, 11 days, 12 days, 13 days, 2 weeks, 3 weeks, 4 weeks, or more than 4 weeks.

[0357] Material properties

[0358] In some embodiments of the methods disclosed above, the 3D-printed orthodontic appliance has a retaining repositioning force (i.e., a repositioning force after the orthodontic appliance has been applied to or worn by the patient for a period of time), and the retaining repositioning force for at least one tooth of the patient after a period of time is at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, or at least 99% of the initial repositioning force applied to at least one tooth of the patient (i.e., at the time of initial application of the orthodontic appliance). In some embodiments, this time period is 3 days, 4 days, 5 days, 6 days, 7 days, 8 days, 9 days, 10 days, 11 days, 12 days, 13 days, 2 weeks, 3 weeks, 4 weeks, or more than 4 weeks.

[0359] In some embodiments, the orthodontic appliances disclosed herein can provide non-deviation movement of at least one tooth of a patient. Non-deviation movement is further described herein (e.g., in Table 1). In some embodiments, the orthodontic appliances disclosed herein can be used to achieve non-deviation movement of at least one tooth of a patient to intermediate tooth alignment. In some embodiments, the orthodontic appliances disclosed herein can be used to achieve non-deviation movement of at least one tooth of a patient to final tooth alignment.

[0360] In some embodiments, the orthodontic appliance includes a first bending stress before moving at least one of the patient's teeth to a central or final alignment without deviation using the orthodontic appliance; and after achieving non-deviation movement of at least one of the patient's teeth to a central or final alignment, the orthodontic appliance includes a second bending stress. In some embodiments, the second bending stress is 80 MPa to 0.5 MPa, 70 MPa to 0.5 MPa, 60 MPa to 1 MPa, 50 MPa to 1 MPa, 40 MPa to 1 MPa, 30 MPa to 2 MPa, 25 MPa to 2 MPa, 20 MPa to 2 MPa, 15 MPa to 2 MPa, or 15 MPa to 0.01 MPa. In some embodiments, the bending stress is evaluated according to ASTM E328. In some embodiments, the time period between the initial placement of the orthodontic appliance on the patient's teeth and the achievement of non-deviation movement is 3 days, 4 days, 5 days, 6 days, 7 days, 8 days, 9 days, 10 days, 11 days, 12 days, 13 days, two weeks, or less than two weeks.

[0361] In some embodiments, the orthodontic appliance has the property of being retained after use of the orthodontic appliance before moving at least one of the patient's teeth toward intermediate or final alignment using the orthodontic appliance.

[0362] As provided herein, the disclosed methods can be used with orthodontic instruments further disclosed herein. These orthodontic instruments can be directly manufactured using resins, such as those disclosed herein. In some embodiments, direct manufacturing includes cross-linking resins.

[0363] The instruments formed from the resins disclosed herein offer improved durability, strength, and flexibility, which in turn improve the rate of non-deviation progression in treatment plans. In some embodiments, patients treated with orthodontic instruments (e.g., braces) disclosed herein with greater than 60%, greater than 70%, greater than 80%, greater than 90%, or greater than 95% of their total treatment are classified as non-deviational at a given treatment stage. In some embodiments, patients treated with orthodontic instruments (e.g., braces) disclosed herein with greater than 60%, greater than 70%, greater than 80%, greater than 90%, or greater than 95% of their total treatment have tooth movements of greater than 50%, greater than 55%, greater than 60%, greater than 65%, greater than 70%, greater than 75%, greater than 80%, greater than 85%, greater than 90%, or greater than 95% of their total treatment are classified as non-deviational.

[0364] Example

[0365] The specific composition, synthesis, formulation, and description of any materials, apparatus, systems, and components thereof disclosed herein can be readily modified according to their intended application, as will be apparent to those skilled in the art. Furthermore, it should be understood that the examples and aspects described herein are for illustrative purposes only, and various modifications or alterations may be suggested to those skilled in the art based thereon, and are included within the spirit and scope of this application and the appended claims. Many different combinations of the aspects described herein are possible, and such combinations are considered part of this disclosure. Moreover, all features discussed in conjunction with any aspect herein can be readily applied to other aspects herein. The use of different terms or reference numerals for similar features in different aspects does not necessarily imply differences other than those expressly set forth. Therefore, this disclosure is intended to be described solely by reference to the appended claims, and not to be limited to the aspects disclosed herein.

[0366] Example 1

[0367] Pressure-sensitive adhesive

[0368] This example describes applying pressure to layers of resin material to at least partially melt these layers, thereby laminating them.

[0369] like Figure 11A As shown, two solid resin strips with melting points of 50°C to 60°C were obtained. The resin strips comprised 80 wt% poly(caprolactone) diacrylate with approximately 10 kMn, 19 wt% tricyclodecanediol diacrylate, and 1 wt% TPO (photoinitiator). The resin was cast into a sheet and allowed to solidify. The first solid resin strip was placed on top of the second solid resin strip. Pressure was applied to the central portion of the stacked sheet while the resin stack was at room temperature. Figure 11B As shown, at least partial melting of the resin was observed and the layers were fused together where pressure was applied (e.g., the central region has at least some translucency).

[0370] This example demonstrates that solid materials (such as resins applied by the system and method described herein, especially uncured resins) can be laminated by applying pressure. When the solid resin layers are close to their melting point, a small amount of pressure is sufficient to induce some melting (e.g., at the interface between the two layers), thereby pressing the two resin segments together. The closer the material is to its melting point, the less force or time is required to apply sufficient pressure to achieve successful lamination. As further described herein, exposure of the material to a light source after lamination (e.g., photopolymerization of the material) will result in a permanent bond between the two layers.

[0371] Example 2

[0372] Adhesive solid resin sheets

[0373] This example shows a resin layer that is applied together and cured to form two desired layers of adhesive material.

[0374] Obtain two solid resin strips as described in Example 1. Figure 12A As shown, these resin strips have melting points ranging from 50°C to 60°C and are heated to approximately 50°C. By heating the resin strips to near their melting temperature, lamination of the two solids is facilitated (e.g., lamination is achieved by applying a small force). Solid resin strips are as follows... Figure 12B The layers are stacked and light or even pressure is applied to bond the two layers together (i.e., the layers are laminated).

[0375] A mask is placed on the laminated resin layer. The mask represents a projected image applicable to the materials and methods described herein. The sample is then illuminated with the mask in place, thereby exposing the areas of the photopolymerized layered solid resin, such as... Figure 12C As shown. Then, the cured sample is heated to 90°C using a hot plate. (See figure) Figure 12D As shown, the uncured resin melts off the sample, while the cured material (i.e., the portion exposed by the mask and photopolymerized) remains intact.

[0376] Scrape off the molten, uncured resin from the cured sample, leaving the clean, cured portion of the sample, such as... Figure 12E As shown. The photocured portion of the solid material was heated to 130°C to demonstrate that the cured polymer material did not melt within the same temperature range as the uncured resin. Figure 12F ).

[0377] After photopolymerization and removal of uncured resin, such as Figure 12G The sample was post-cured using light and heat. Post-curing ensured that the material was fully cured and possessed the desired final properties of the polymer material. The finally cured polymer material served as a single solid segment (in contrast to two separate solid layers placed together). Attempts to pull the two layers apart were unsuccessful. This demonstrates that lamination and curing successfully formed multiple solid resin sheets into a single material.

[0378] This example demonstrates that solid resin sheets or layers (e.g., uncured resin) can be laminated together and cured in a feasible manner to produce 3D objects as further described herein. This example shows that lamination printing can produce 3D parts with precision similar to stereolithography. This example also demonstrates the potential to form phase-separated materials with composite-like properties (e.g., by applying a mask during photopolymerization).

[0379] The uncured resin, which was melted and removed from the cured sample, was recast into a solid, and the experiment was repeated using recycled material. Products produced from the recycled resin were substantially similar to those produced from the virgin material (i.e., in the first iteration of the experiment). This result demonstrates the recyclability of the resin, as further described in the systems and methods disclosed herein.

[0380] Example 3

[0381] 3D objects formed from solid resin sheets

[0382] This example illustrates the formation of a 3D object from a solid resin sheet, as further described herein.

[0383] A resin mixture comprising 99 wt% polycaprolactone diacrylate (10 kMw) and 1 wt% diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO, photoinitiator) is heated to 90°C to form a hot and flowable resin. The hot resin is applied as a thin layer onto a polyester film (i.e., a carrier film) using a pull rod. The resin is then transported onto a cold metal plate (i.e., a cooling element), with the polyester film adhering tightly to the surface of the cold metal plate. The resin is cooled, and the polycaprolactone diacrylate is solidified by crystallization.

[0384] Solidified and cooled resin layers are transported and applied to a build platform, with a polyester film positioned between the applied resin and a light source. The solid resin layers are selectively photocured in one or more regions using the light source, and the polyester film is removed. This process is repeated by adding successive layers of solid resin to build a 3D object on the build platform. The resulting 3D object is essentially surrounded by uncured resin (i.e., for each layer, selectively photopolymerized regions form a 3D object comprising the polymerized material, while non-photopolymerized regions contain uncured resin). The resulting build object is removed from the build block and heated to reduce the viscosity of the uncured resin, causing it to flow away from the photocured 3D object. The uncured resin is collected and reused.

[0385] In some cases, solvents are used to clean photocured 3D objects to dissolve or otherwise remove uncured resin, and the objects are centrifuged to facilitate the removal of uncured resin and / or solvent from the photocured objects. In some cases, the cleaned 3D objects are post-cured in a lightbox and / or oven.

[0386] The resulting 3D objects exhibit the desired polymer material properties, and their detailed shape can be controlled, for example, by masking and controlling exposure during the photopolymerization step. This result demonstrates that 3D objects can be formed using solid resin sheets, as further described herein. The results also show that the shape of such 3D objects can be fine-tuned, and the resulting material properties are controllable. Furthermore, this result indicates that the uncured resin can be reused or recycled.

[0387] Interlayer adhesion depends on the printing temperature. If the resin is far below its melting point, interlayer adhesion is found to be very poor. Interlayer adhesion is greatly improved when the solid resin temperature is set just below or equal to the resin's melting temperature.

[0388] Furthermore, selectively heating previously printed (exposed or cured) layers or depositing uncured solid or semi-solid resins onto the printed surface using infrared light (or contact with, for example, a hot plate) also provides good interlayer adhesion after curing. Depending on the layer thickness, heated insulating surfaces can be obtained in some samples, thus preserving the crystalline structure within the layer. This surface heating can be amplified by adding a small amount of pigment material (e.g., carbon black (e.g., using a sprayer on the layer)). In the latter case, the pigment material (e.g., carbon black) also acts as a light-blocking agent to prevent light from penetrating far into the next layer.

[0389] Interlayer adhesion can also be controlled in the x and y dimensions of each layer using selective heating via a mask (or DMD, digital micromirror device), allowing the creation of cured layers with both adhesive and unbonded characteristics within the printed part. This effectively allows for the creation of slip zones within the printed part (e.g., controlling layer delamination or slippage when pressed) in certain portions of the printed part, while other portions do not. This is a beneficial design feature for controlling, for example, where and / or how much stress would cause interlayer adhesion failure.

[0390] Example 4

[0391] Multiphase materials formed from solid resins

[0392] This example describes the formation of a multiphase polymer material from a single solid resin sheet, which can be used to form objects in the methods and systems further described herein.

[0393] The formed resin comprised 95 wt% polycaprolactone diacrylate (14Mn), 4 wt% 3,3,5-trimethylcyclohexyl-2-(methacryloyloxy)benzoate (HSMA, monofunctional methacrylate), and 1 wt% diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO, photoinitiator). The resin was heated to 80°C to form a hot, homogeneous, transparent liquid. Resin samples were prepared by pouring the resin onto glass slides, with a 1 mm spacer provided before placing a second slide on top to form a sandwich (i.e., the resin was positioned between two glass slides spaced 1 mm apart). The resin layer was then cooled to room temperature by placing it on a large metal plate, which served as a heat sink. Phase separation occurred in the resin sample as some of the polycaprolactone formed a crystalline phase within the material during cooling, and the resin sample was observed to change from transparent to white.

[0394] The sample solid resin layer was evenly and separately placed between two metal plates. The first of the two metal plates was set to provide a temperature of 80°C, while the second of the two metal plates was set to provide a temperature of 30°C (i.e., the resin was temperature-controlled to have a first region at a first temperature and a second region at a second temperature). Figure 13A As shown, the first region of the solid resin (i.e., the region heated to 80°C) is transparent, while the second region of the solid resin (i.e., the region heated to 30°C) remains cloudy white. Because polycaprolactone is in the molten phase, the region heated to 80°C appears transparent, allowing it to mix freely and diffuse into the resin to become homogeneous. In contrast, the region heated to 30°C is cloudy because polycaprolactone crystals are present in this region.

[0395] A second resin sample was prepared by similarly adding glass filler. The second sample was then similarly heated, with the first region heated to 80°C and the second region heated to 30°C. In the second sample including the glass filler, the region heated to 80°C was significantly more transparent than the region heated to 30°C, although both sides remained cloudy due to the presence of the glass filler. Figure 13B As shown. The glass filler scatters light, thus maintaining a cloudy visualization.

[0396] While the first sample was held at two temperatures (i.e., the first region was heated to 80°C and the second region to 30°C), the two regions, including the resin, were photopolymerized for 30 seconds using a Dymax light source. The photopolymerized sample was then placed on a hot plate and post-cured at 100°C for 6 minutes in a Dymax curing chamber. The polymerized sample was then cooled to room temperature, allowing for the observation and determination of the different optical and physical properties of the first and second regions corresponding to the first and second temperatures, respectively. The modulus of the second region (i.e., the region photopolymerized at 30°C) was 200 MPa higher than that of the first region (i.e., the region photopolymerized at 80°C). The second region (i.e., the region photopolymerized at 80°C) was also significantly more transparent and less cloudy than the first region (i.e., the region photopolymerized at 30°C). This indicates that the temperature of the resin region maintained during curing significantly affects the physical properties of the resulting polymerized material.

[0397] The third resin sample was prepared similarly to the first sample, with the first region of the sample cooled and allowed to crystallize, while the second region was maintained at 90°C. The second region was a clear solution because polycaprolactone melted at 60°C (i.e., no crystallization occurred in the heated region, and the polycaprolactone was in a molten state). The entire sample was photopolymerized for 30 seconds using a Dymax light source, followed by post-curing at 90°C for 6 minutes in a lampbox. It was observed that even during the post-curing process where the entire sample was heated to 90°C, the first region remained white, indicating that the crystalline polycaprolactone was locked within the phase-separated material and did not melt like the heated resin. After post-curing and subsequent cooling to room temperature, the second region (i.e., the region photopolymerized at 90°C) showed crystallization of the polymerized polycaprolactone, as... Figure 13CAs shown (the left side is the first region, photopolymerizing while cooling, and the right side is the second region, photopolymerizing while heating). The size of the domains in the crystalline regions can also be controlled by controlling the temperature during photopolymerization. The cold-cured surface has larger crystalline domains compared to the thermosetting surface. In this sample, the region between the two temperatures appears to have the smallest domain size (i.e., the most translucent region), implying the existence of an intermediate temperature that produces a more uniform material than the 30°C or 90°C regions. Without being bound by any specific theory, the thermosetting region may undergo photopolymerization-induced phase separation (PIPS), which allows poly(caprolactone) to form its own phase, which then crystallizes upon cooling, whereas the intermediate region lacks sufficient chain mobility and / or diffusion to cause such phase separation, resulting in a more uniformly mixed polymer matrix where poly(caprolactone) crystallization is significantly reduced. This suggests that materials formed using the processes and methods described herein can contain at least three distinct phases in a multiphase system (e.g., an amorphous polymer phase, a crystalline polymer phase, and silica as a discontinuous inorganic amorphous glass phase). This example also demonstrates the control of a gradient of material properties between two temperature-controlled regions, each with different material properties that are directly related to the temperature at which photopolymerization occurs.

[0398] Example 5

[0399] Materials from solid resins with fillers

[0400] This example describes a polymer material formed from a single solid resin sheet including fillers. The properties of the material photopolymerized at different temperatures are determined.

[0401] A resin was prepared comprising 50.5 wt% polycaprolactone diacrylate (14Mn), 43.85 wt% 3,3,5-trimethylcyclohexyl-2-(methacryloyloxy)benzoate (HSMA, monofunctional methacrylate), 4.7 wt% glass filler (approximately 800 μm), and 0.95 wt% diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO, photoinitiator). The resin sample was divided into two parts. The first part was heated to 90°C and photopolymerized by exposing the resin to a Dymax light source for 3 minutes to form a first polymeric material (i.e., the thermocured sample). The thermocured sample was allowed to cool to room temperature, and crystallization of polycaprolactone was subsequently observed.

[0402] The second part of the resin sample was heated to 90°C and then cooled to room temperature. Crystallization was observed, and the sample was then photopolymerized to form a second polymerized material (i.e., the cold-cured sample) by exposing the resin to a Dymax light source for 30 seconds. The sample was then post-cured by heating to 90°C and cured in a Dymax light source for 3 minutes. Even when heated to 90°C, the cold-cured material, including the crystalline material, remained white in appearance, indicating that the crystal domains did not melt, or suggesting that the crystal domains contained non-aggregated air voids, which is expected to occur when heated above 60°C. Typically, the melting point of polycaprolactone crystals is around 60°C, but the cold-polymerized sample did not become transparent upon heating (unlike the hot-cured sample, which becomes transparent when heated above 60°C), thus indicating that some internal structures were locked in during the cold polymerization process and were difficult to change.

[0403] Both thermosetting and cold-setting samples were stored at room temperature for 48 hours prior to evaluation using dynamic thermomechanical analysis. Figure 14 As shown, the storage modulus (MPa as a function of temperature) and TanDelta (as a function of temperature) were determined in dynamic thermomechanical analysis. The addition of glass fibers appears to affect the crystallization behavior of polycaprolactone diacrylate, as both the thermo-cured and cold-cured samples exhibit relatively high glass transition temperatures. The cold-cured sample showed a relatively high modulus measured at 40 °C (e.g., close to the intraoral temperature), higher than that of the thermo-cured sample. This indicates that enhanced crystallization occurred in the cooled and crystallized resin, which can be aided by the addition of glass fiber filler. This result suggests that fillers such as glass fibers can be added to the resins described herein to enhance phase separation and / or act as crystallization seeds for multiphase materials.

[0404] Example 6

[0405] Rapid heating solid resin

[0406] This example describes the use of a heat source to form a multiphase polymer material from a single solid resin sheet to achieve rapid, regional temperature control of the heated area.

[0407] The resulting resin comprises 95 wt% polycaprolactone diacrylate (14Mn), 4 wt% 3,3,5-trimethylcyclohexyl-2-(methacryloyloxy)benzoate (HSMA, monofunctional methacrylate), and 1 wt% diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO, photoinitiator). The resin is heated to 80°C to form a hot, homogeneous, transparent liquid. A layer sample of the resin is prepared by pouring the resin onto a 100-micron fluoropolymer sheet (avoiding the use of glass as a heat sink). The resin is spread onto the fluoropolymer film and allowed to cool, then solidified as the polycaprolactone crystallizes. The film carrying the resin sample is suspended in air by attaching clamps to each end of the fluoropolymer film with resin at the top. A heating lamp (e.g., an infrared light source) is placed near the resin sample. A square mask is placed on top of the sample such that the projected light exposes the center of the square sample. The heating lamp was activated for 10 seconds, and a square image projected through the square mask was observed, showing a clear point in the center of the sample surrounded by cloudy, white, cold resin. The heating lamp was removed, and the entire resin sample (i.e., without the mask) was photopolymerized for 15 seconds using a 495 nm Semray LED curing system. The sample was then placed on a hot metal plate set to 100°C in a Dymax curing chamber and post-cured for 6 minutes. The sample was then cooled to room temperature, and a square portion was observable in the center of the sample, corresponding to the area exposed to the heating lamp (e.g., exposed to infrared irradiation). The central square portion was observed to have less white cloudiness and higher transparency, indicating less crystallinity and / or smaller crystal domains inside the square compared to other areas of the multiphase material (i.e., areas cured without heating). The material region inside the square was softer (i.e., had a lower modulus) than the material outside the square.

[0408] This demonstrates that infrared light can be used to selectively heat portions of a single layer of resin prior to curing, and that this process alters the physical and visual properties of the cured material. It also shows that infrared light sources can heat resin layers very rapidly, as further described herein, indicating that this heating can be used, for example, to quickly adjust individual layers when printing objects using a 3D printer (e.g., those further described herein).

[0409] Example 7

[0410] Treatment using orthodontic instruments

[0411] This example illustrates the use of directly 3D-printed orthodontic appliances to move a patient's teeth according to a treatment plan. The example also describes the properties that the orthodontic appliance may possess after use, compared to its properties before use.

[0412] A patient requiring or desiring therapeutic treatment to realign at least one tooth has an assessed dental alignment. An orthodontic treatment plan is generated for the patient. The orthodontic treatment plan includes multiple intermediate dental alignments for moving teeth along a treatment path from the initial alignment (e.g., the alignment initially assessed) to the final alignment. The treatment plan includes the use of orthodontic appliances manufactured using the printable resins and methods further disclosed herein. In some embodiments, multiple orthodontic appliances are used, each of which can be manufactured using the printable resins and methods further disclosed herein.

[0413] Orthodontic appliances are provided and iteratively applied to the patient's teeth to move them toward the final alignment through each intermediate tooth arrangement. The patient's tooth movement is tracked. A comparison is made between the patient's actual tooth alignment and the planned intermediate alignment. If it is determined that the patient's teeth are being tracked according to the treatment plan but have not yet reached the final alignment, the next set of appliances can be administered to the patient. Table 1 above provides threshold differences between the planned and selected actual positions of the teeth to indicate whether the patient's teeth have progressed without deviation. If the patient's teeth have progressed to or within the threshold, progress is considered without deviation. Advantageously, using the appliances disclosed herein increases the likelihood of undevised tooth movement.

[0414] One week (7 days) after the initial application of orthodontic appliances, an assessment and determination can be made to ensure that the treatment has not deviated from its intended course. Following this application period, additional parameters related to evaluating the durability of the orthodontic appliances can be determined. For example, relative repositioning force (compared to the force initially provided by the appliance), residual flexural stress, relative flexural modulus, and relative elongation at break can be determined.

Claims

1. A method for producing polymer materials, the method comprising: Provide resin; Controlling the temperature of the resin, the resin comprising: A first region having a first temperature; and A second region having a second temperature; The resin is polymerized to form a polymer material, wherein polymerizing the polymer material further includes generating a first polymerization region and a second polymerization region; and The object is manufactured using the polymer material. The object comprises multiple regions having at least one distinct characteristic, wherein the at least one distinct characteristic is selected from the group consisting of: elongation at break, storage modulus, tensile modulus, residual stress, glass transition temperature, water absorption, hardness, color, transparency, hydrophobicity, lubricity, surface texture, crystallinity percentage, and phase composition ratio. Each of the plurality of regions has a shape dimension of less than 250µm.

2. The method according to claim 1, wherein, The temperature of the resin is controlled spatially.

3. The method according to any one of claims 1-2, wherein, The temperature of the resin is controlled spatially in the xy dimension.

4. The method according to any one of claims 1-2, wherein, The temperature of the resin is controlled spatially, perpendicular to the light curing light source.

5. The method according to any one of claims 1-2, wherein, The temperature of the resin is controlled spatially in the x-dimensional, y-dimensional, and / or z-dimensional directions.

6. The method according to claim 5, wherein, The z-dimensional dimension refers to the direction of light emitted from the photocuring light source.

7. The method according to claim 1, wherein, The first polymerization region has at least one characteristic that is different from the second polymerization region, and the at least one characteristic is selected from the group consisting of elongation at break, storage modulus, tensile modulus, residual stress, color, transparency, hydrophobicity, lubricity, surface texture, crystallinity percentage and phase composition ratio.

8. The method according to any one of claims 1-2, wherein, Controlling the temperature includes heating or cooling the resin in the first region to a first temperature.

9. The method according to any one of claims 1-2, wherein, Controlling the temperature includes heating or cooling the resin in the second region to a second temperature.

10. The method according to claim 8, wherein, Heating the resin in the first region and / or heating the resin in the second region includes exposure to a light source.

11. The method according to claim 10, wherein, The light source is an infrared light source.

12. The method according to any one of claims 1-2, wherein, The difference between the first temperature and the second temperature is 5°C or greater.

13. The method according to any one of claims 1-2, wherein, The polymerization of the resin includes photopolymerization.

14. The method according to any one of claims 1-2, further comprising providing a mask.

15. The method according to any one of claims 1-2, further comprising thermosetting the polymer material.

16. The method according to any one of claims 1-2, further comprising photocuring the polymer material.

17. The method according to any one of claims 1-2, further comprising applying the resin to a substrate.

18. The method according to claim 17, wherein, The substrate includes a fluoropolymer.

19. The method according to claim 1, wherein, The manufacturing process includes printing the resin using a 3D printer.

20. The method according to claim 1, wherein, The manufacturing process includes stereolithography, digital light processing, two-photon induced photopolymerization, inkjet printing, multi-jet printing, fused deposition modeling, or any combination thereof.

21. The method according to claim 1, wherein, Each of the multiple regions has a shape dimension of less than 200µm.

22. The method according to claim 1, wherein, The object has one to three fixed dimensions of less than 250µm for any particular region of voxel size.

23. The method according to any one of claims 1-2, wherein, The resin comprises a crystalline material and one of the first or second regions comprises a crystalline material in a molten form.

24. The method according to any one of claims 1-2, wherein, The resin is homogeneous.

25. The method according to any one of claims 1-2, wherein, The resin phase separates into two or more phases before polymerization.

26. The method of claim 25, wherein, The resin phase separates when the temperature changes.

27. The method according to claim 25, wherein, The resin phase separates during photopolymerization.

28. The method according to any one of claims 1-2, wherein, The resin comprises a plurality of monomers, most of which are copolymerized at the first temperature and homopolymerized at the second temperature.

29. The method according to any one of claims 1-2, wherein, The resin comprises a plurality of monomers, most of which are copolymerized at the second temperature and homopolymerized at the first temperature.

30. The method according to any one of claims 1-2, wherein, Controlling the temperature of the resin initiates a secondary chemical reaction.

31. The method according to claim 30, wherein, The secondary chemical reaction includes ionothermal reaction, epoxide polymerization, ionothermal polymerization, bond breaking reaction, bond formation reaction, catalyst activation, or any combination thereof.

32. The method according to claim 1, wherein, The object in question is an orthodontic device.

33. The method according to claim 32, wherein, The orthodontic instruments are braces, expanders, or spacers.

34. The method according to claim 32, wherein, The orthodontic appliance includes multiple tooth-receiving cavities configured to reposition teeth from a primary form to a secondary form.

35. The method according to claim 32, wherein, The orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial configuration to a target configuration.

36. The method according to claim 32, wherein, The orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial configuration to a target configuration according to a treatment plan.

37. The method according to any one of claims 1-2, wherein, The difference between the first temperature and the second temperature is 10°C or greater.

38. The method according to any one of claims 1-2, wherein, The difference between the first temperature and the second temperature is 15°C or greater.

39. The method according to any one of claims 1-2, wherein, The difference between the first temperature and the second temperature is 20°C or greater.

40. The method according to any one of claims 1-2, wherein, The difference between the first temperature and the second temperature is 30°C or greater.

41. The method according to any one of claims 1-2, wherein, The difference between the first temperature and the second temperature is 40°C or greater.

42. The method according to any one of claims 1-2, wherein, The difference between the first temperature and the second temperature is 50°C or greater.

43. The method according to any one of claims 1-2, wherein, The difference between the first temperature and the second temperature is greater than 50°C.

44. The method according to claim 1, wherein, Each of the multiple regions has a shape dimension of less than 150µm.

45. The method according to claim 1, wherein, Each of the multiple regions has a shape dimension of less than 100µm.

46. ​​The method according to claim 1, wherein, Each of the multiple regions has a shape dimension of less than 90µm.

47. The method according to claim 1, wherein, Each of the multiple regions has a shape dimension of less than 80µm.

48. The method according to claim 1, wherein, Each of the multiple regions has a shape dimension of less than 70µm.

49. The method according to claim 1, wherein, Each of the multiple regions has a shape dimension of less than 60µm.

50. The method according to claim 1, wherein, Each of the multiple regions has a shape dimension of less than 50µm.

51. The method according to claim 1, wherein, Each of the multiple regions has a shape dimension of less than 40µm.

52. The method according to claim 1, wherein, Each of the multiple regions has a shape dimension of less than 30µm.

53. The method according to claim 1, wherein, Each of the multiple regions has a shape dimension of less than 20µm.

54. The method according to claim 1, wherein, Each of the multiple regions has a shape dimension of less than 10µm.

55. The method according to claim 1, wherein, The object has one to three fixed dimensions of less than 200µm for any particular region of voxel size.

56. The method according to claim 1, wherein, The object has one to three fixed dimensions of less than 150µm for any particular region of voxel size.

57. The method according to claim 1, wherein, The object has one to three fixed dimensions of less than 100µm for any particular region of voxel size.

58. The method according to claim 1, wherein, The object has one to three shape dimensions of less than 90µm for any particular region of voxel size.

59. The method according to claim 1, wherein, The object has one to three fixed dimensions of less than 80µm for any particular region of voxel size.

60. The method according to claim 1, wherein, The object has one to three shape dimensions of less than 70µm for any particular region of voxel size.

61. The method according to claim 1, wherein, The object has one to three shape dimensions of less than 60µm for any particular region of voxel size.

62. The method according to claim 1, wherein, The object has one to three shape dimensions of less than 50µm for any particular region of voxel size.

63. The method according to claim 1, wherein, The object has one to three shape dimensions of less than 40µm for any particular region of voxel size.

64. The method according to claim 1, wherein, The object has one to three shape dimensions of less than 30µm for any particular region of voxel size.

65. The method according to claim 1, wherein, The object has one to three shape dimensions of less than 20µm for any particular region of voxel size.

66. The method according to claim 1, wherein, The object has one to three fixed dimensions of less than 10µm for any particular region of voxel size.

67. A polymer material formed by the method according to any one of claims 1-66.

68. The polymer material according to claim 67, wherein, The polymer material is characterized by one or more of the following: Elongation at break greater than or equal to 5%; Energy storage modulus greater than or equal to 500 MPa; Tensile modulus greater than or equal to 500 MPa; The residual stress is greater than or equal to 0.01 MPa; as well as After soaking in water for 24 hours, the flexural modulus is greater than or equal to 60 MPa.

69. The polymer material according to claim 67, wherein, The polymer material is characterized in that the residual stress is 5% to 45% of the initial load.

70. The polymer material according to claim 67, wherein, The polymer material is characterized by a tensile modulus ranging from 500 MPa to 2000 MPa.

71. The polymer material according to claim 67, wherein, The polymer material is characterized by having an elongation at break greater than 10%.

72. The polymer material according to claim 67, wherein, The polymer material is characterized by a storage modulus of 750 MPa to 3000 MPa.

73. The polymer material according to claim 67, wherein, The polymer material is characterized by a residual stress of 0.01 MPa to 15 MPa.

74. The polymer material according to claim 73, wherein, The residual stress was measured after immersion in an aqueous solution for 24 hours.

75. The polymer material according to claim 67, wherein, The polymer material is characterized in that the residual stress is 20% to 45% of the initial load.

76. The polymer material according to claim 67, wherein, The polymer material is characterized by a tensile modulus ranging from 800 MPa to 2000 MPa.

77. The polymer material according to claim 67, wherein, The polymer material is characterized by having an elongation at break greater than 20%.

78. The polymer material according to claim 67, wherein, The polymer material is characterized by having an elongation at break greater than 30%.

79. The polymer material according to claim 67, wherein, The polymer material is characterized by an elongation at break of 5% to 250%.

80. The polymer material according to claim 67, wherein, The polymer material is characterized by an elongation at break of 20% to 250%.

81. The polymer material according to claim 67, wherein, The polymer material is characterized in that its elongation at break is between 40% and 250%.

82. The polymer material according to claim 67, wherein, The polymer material is characterized by a residual stress of 2 MPa to 15 MPa.

83. A system for forming an object according to any one of claims 1-66, the system comprising: A resin injector configured to dispense resin; First temperature control element; light source; The platform is built and configured to retain objects; as well as A carrier platform configured to deliver resin from the resin injector to the first temperature control element, the light source, and the construction platform.

84. The system according to claim 83, wherein, The building platform is configured to move horizontally.

85. The system according to claim 83, wherein, The first temperature control element is positioned after the resin injector and configured to reduce the temperature of the resin.

86. The system according to claim 83, wherein, The first temperature control element is positioned after the thickness controller and configured to reduce the temperature of the resin.

87. The system according to claim 83, wherein, The first temperature control element is positioned in the resin injector and configured to increase the temperature of the resin.

88. The system according to claim 83, wherein, The first temperature control element includes a cooling plate.

89. The system according to claim 88, wherein, The cooling plate is connected to a cooler or thermoelectric cooling system.

90. The system according to claim 83, wherein, The resin syringe heats the resin.

91. The system according to claim 83 further includes a second temperature control element.

92. The system according to claim 91, wherein, The second temperature control element is configured to increase the temperature of the resin.

93. The system according to claim 91, wherein, The second temperature control element includes a heater.

94. The system according to claim 91, wherein, The second temperature control element is a remelter.

95. The system according to claim 91, wherein, The second temperature control element includes a light source.

96. The system according to claim 83, wherein, The carrier platform is configured to move along the horizontal plane at a first speed, and the construction platform is configured to move along the horizontal plane at a second speed.

97. The system according to claim 83, wherein, The construction platform is configured to apply pressure to the carrier platform or receive pressure from the carrier platform.

98. The system according to claim 83, wherein, The resin injector is configured to dispense resin in a heated form.

99. The system according to claim 83, wherein, The carrier platform is a membrane.

100. The system according to claim 83, wherein, The light source is configured to emit ultraviolet light, infrared light, visible light, or any combination thereof.

101. The system of claim 83 further includes a layer thickness controller.

102. The system according to claim 101, wherein, The layer thickness controller includes a scraper.

103. The system according to claim 83, wherein, The carrier platform is configured to repeatedly apply the resin to the construction platform and / or repeatedly apply the resin to the resin applied to the construction platform.

104. The system according to claim 91, wherein, The second temperature control element is configured to heat the uncured resin attached to the carrier platform.

105. The system according to claim 104, wherein, The second temperature control element is configured to heat the uncured resin after the carrier platform has passed through the construction platform.

106. The system according to claim 83, wherein, The system is configured to recycle uncured resin.

107. The system according to claim 91 further includes an infrared heating element.

108. The system according to claim 107, wherein, The infrared heating element is configured to heat the region of the resin.

109. The system according to claim 108, wherein, The first surface of the resin is heated to a higher temperature than the second surface of the resin.

110. The system according to claim 107, wherein, The infrared heating element is positioned below the carrier platform.

111. The system according to claim 107, wherein, The infrared heating element is positioned above the carrier platform.

112. The system of claim 107 further includes a particle applicator.

113. The system according to claim 112, wherein, The particle applicator is a funnel or a sprayer.

114. The system according to claim 112, wherein, The microparticle applicator is configured to apply an adhesive enhancer to the resin.

115. The system according to claim 114, wherein, The adhesive enhancer includes a powdered adhesive enhancer or a liquid adhesive enhancer.

116. The system according to claim 114, wherein, The adhesive enhancer includes infrared absorbing compounds, carbon black, dyes, multiphoton absorbers, metal particles, nanoparticles, water absorbed into silica, or any combination thereof.

117. The system according to claim 114, wherein, The adhesive enhancer includes adhesives and / or monomer systems.

118. The system according to claim 112, wherein, The microparticle applicator is configured to apply a light absorber to the resin.

119. The system according to claim 118, wherein, The light absorber is applied as a thin layer.

120. The system according to claim 118, wherein, The light absorber is applied to at least one side of the resin.

121. The system according to claim 118, wherein, The light absorber is applied to one side of the resin.

122. The system according to claim 118, wherein, The light absorber is applied to at least both sides of the resin.

123. The system according to claim 118, wherein, The light absorber is applied to both sides of the resin.

124. The system according to claim 118, wherein, The particulate applicator is also configured to apply adhesive enhancers, adhesive monomers, or combinations thereof.

125. The system according to claim 107, wherein, The infrared heating element is configured to emit microwave light.

126. The system according to claim 94, wherein, The carrier platform is configured to transport uncured resin from the build platform to the resin injector.

127. The system according to claim 126, wherein, The carrier platform is configured to transport the uncured resin from the build platform to the remelter and from the remelter to the resin injector.

128. The system according to claim 83, wherein, The carrier platform is configured to move along a horizontal plane, and the construction platform is configured to move along a vertical plane.

129. The system according to claim 83, wherein, The carrier platform is configured to move along a vertical plane.

130. The system of claim 112, further comprising: The first feed roll is configured to apply a carrier platform without resin; And the first reel, which is configured to receive a carrier platform carrying uncured resin.

131. The system according to claim 83, wherein, The first temperature control element includes a cooling plate, a fan, a water bath, a cooling roller, or any combination thereof.

132. The system according to claim 83, wherein, The first temperature control element is supplied with air, inert gas, or a rapidly evaporating material.

133. The system according to claim 132, wherein, The rapidly evaporating material includes butane, liquid nitrogen, solid carbon dioxide, or a combination thereof.

134. The system according to claim 112, wherein, The particulate applicator is configured to apply an anti-adhesion agent to the resin.

135. The system according to claim 134, wherein, The anti-adhesion agent prevents the layers of the resin from sticking together.

136. The system according to claim 130, wherein, The resin injector and the first temperature control element are located between the first feed roll and the first reel.

137. The system according to claim 130, wherein, The second temperature control element, the particle applicator, or a combination thereof are located between the first feed roll and the first reel.

138. The system of claim 130, further comprising a second feed roll and a second reel.

139. The system according to claim 138, wherein, The second feed roll is formed from the first roll reel.

140. The system according to claim 138, wherein, The construction platform is configured to receive the resin from the carrier platform.

141. The system according to claim 138, wherein, The light source and the construction platform are located between the second feed roll and the second reel.

142. The system of claim 83 further includes a window located between the light source and the construction platform.

143. The system according to claim 138, wherein, The infrared heating element is located between the second feed roll and the second reel.

144. The system of claim 83 further includes a cutting device.

145. The system according to claim 144, wherein, The cutting device includes a die-cutting machine.

146. The system according to claim 144, wherein, The cutting device is configured to cut uncured resin into multiple uncured resin sheets.

147. The system of claim 146 further includes a robotic arm configured to move at least some of the plurality of uncured resin sheets.

148. The system according to claim 147, wherein, The robotic arm is configured to move at least some of the plurality of uncured resin sheets to the build platform.

149. The system of claim 146, further comprising a storage device configured to store the plurality of uncured resin sheets.

150. The system of claim 83 further includes a mask.

151. The system according to claim 83, wherein, The object in question is an orthodontic device.

152. The system according to claim 151, wherein, The orthodontic instruments are braces, expanders, or spacers.

153. The system according to claim 151, wherein, The orthodontic appliance includes multiple tooth-receiving cavities configured to reposition teeth from a primary form to a secondary form.

154. The system according to claim 151, wherein, The orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial configuration to a target configuration.

155. The system according to claim 151, wherein, The orthodontic appliance is one of a plurality of orthodontic appliances configured to reposition teeth from an initial configuration to a target configuration according to a treatment plan.

156. The system according to claim 83, wherein, The construction platform is configured to move horizontally in a two-dimensional plane.

157. The system according to claim 83, wherein, The construction platform is configured for vertical movement.

158. The system according to claim 83, wherein, The construction platform is configured to move in three spatial dimensions.

159. The system according to claim 144, wherein, The cutting device includes a laser cutting machine.

160. The system according to claim 144, wherein, The cutting device includes a blade.

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