Elastomer formulations containing polymeric silicone materials usable for additive manufacturing of three-dimensional objects

Abstract

A curable formulation is provided that, upon curing, provides an elastomer material with improved resilience (EDE). The curable formulation comprises a monofunctional elastomer curable material and / or a polyfunctional elastomer curable material, optionally a monofunctional non-elastomer curable material, a polyfunctional non-elastomer curable material, and a curable material containing two or more hydrogen bond-forming groups, and at least one polymeric silicone material as described in the specification and claims. Furthermore, a method for additively manufacturing 3D objects using the curable formulation is also provided.

Description

Technical Field

[0001] (Cross - reference to related applications) This application claims the benefit of priority under 35 USC § 119(e) of U.S. Provisional Patent Application No. 63 / 456,005, filed Mar. 31, 2023, the content of which is incorporated herein by reference in its entirety.

[0002] This application is also related to U.S. Provisional Patent Application No. 63 / 456,011, filed Mar. 31, 2023, and the PCT International Patent Application "FORMULATIONS USABLE IN ADDITIVE MANUFACTURING OF 3D OBJECTS THAT FEATURE AN ELASTOMERIC MATERIAL" (Attorney Docket No. 99137) filed simultaneously by the assignee of this application. This application claims the benefit of priority of U.S. Provisional Patent Application No. 63 / 456,011, filed Mar. 31, 2023, the content of which is incorporated herein by reference as if fully set forth herein in its entirety.

[0003] In some embodiments, the present invention relates to 3D printing, and more specifically, but not limited thereto, to formulations usable in the additive manufacturing of three - dimensional objects that provide an elastomeric (rubbery) material characterized by improved resilience, and methods / processes of using the same.

Background Art

[0004] Additive Manufacturing (AM) is a technology that enables the direct manufacturing of shaped structures from computer data through additional forming steps. The basic operation of an AM system is to slice a three - dimensional computer model into thin cross - sections, convert the results into two - dimensional position data, and supply that data to a control device that manufactures the three - dimensional structure layer by layer.

[0005] Additive manufacturing encompasses a variety of approaches to manufacturing methods, including three-dimensional (3D) printing such as 3D inkjet printing, electron beam melting, stereolithography, selective laser sintering, additive manufacturing, and fused deposition modeling.

[0006] For example, some 3D printing processes, such as 3D inkjet printing, are performed by depositing the material layer by layer using an inkjet. Therefore, the material is extruded from an extrusion head equipped with a set of nozzles and deposited in layers onto a receiving medium. Depending on the material, the layers can optionally be flattened using a leveling device, and then cured or solidified using appropriate equipment.

[0007] Various three-dimensional printing technologies exist, for example, disclosed in U.S. Patents No. 6,259,979, No. 6,569,373, No. 6,658,314, No. 6,850,334, No. 6,863,859, No. 7,183,335, No. 7,209,797, No. 7,225,045, No. 7,300,619, No. 7,500,846, No. 9,031,680 and No. 9,227,365, U.S. Patent Application No. 2006 / 0054039, International Publication No. 2016 / 009426 and International Publication No. 2022 / 024114, all of which are by the assignee of this application and whose contents are incorporated herein by reference in their entirety.

[0008] A printing system used in additive manufacturing may include a receiving medium and one or more print heads. The receiving medium may be, for example, a manufacturing tray including a horizontal surface for holding the material ejected from the print head. The print head may be, for example, an inkjet head having multiple ejection nozzles arranged in one or more arrays along the longitudinal axis of the print head. The print head may be positioned so that its longitudinal axis is substantially parallel to the indexing direction. The printing system may further include a controller, such as a microprocessor, that controls the printing process, including the movement of the print head according to a predefined scan plan (e.g., a CAD configuration converted to stereolithography (STL) format and programmed into the controller). The print head may include multiple ejection nozzles. The ejection nozzles eject material onto the receiving medium, forming layers representing the cross-section of a 3D object.

[0009] In addition to the print head, there may be a curing energy source for curing the extruded material. The curing energy is typically radiation, such as ultraviolet light.

[0010] Furthermore, the printing system may include a flattening device for flattening each layer and / or setting the height of each layer after deposition and at least partial solidification, but before depositing subsequent layers.

[0011] The molding material may include a modeling material and a support material, which each form an object and a temporary support structure that supports the object during molding.

[0012] Modeling material (which may include one or more materials) is deposited to form a desired object or multiple objects, and support material (which may include one or more materials) provides support structures to specific areas of the object during printing, with or without modeling material elements, and is used to ensure the proper vertical alignment of subsequent object layers, for example, when the object includes overhanging features or shapes such as curved shapes, negative angles, or voids.

[0013] Both the modeling material and the support material are preferably liquid at the extrusion operating temperature, and then harden (harden) when exposed to curing energy (e.g., UV curing) to form the desired layer shape. After printing is complete, the support structure is removed, revealing the final shape of the manufactured 3D object.

[0014] To be compatible with most commercially available print heads used in 3D inkjet printing systems, the uncured 3D printing material must have the following characteristics: a relatively low viscosity at the working (e.g., spray) temperature (e.g., Brookfield viscosity of up to 50 centipoise or up to 35 centipoise, preferably 8 to 25 centipoise); a surface tension of about 20 to about 100 Dyne / cm, preferably about 25 to about 40 Dyne / cm; and Newtonian liquid behavior, with high reactivity to curing conditions selected to enable rapid solidification of the sprayed layer in 1 minute or less, preferably 20 seconds or less, upon exposure to curing conditions.

[0015] In 3D inkjet printing processes such as PolyJet® (Stratasys®, Israel), the build material is selectively ejected from one or more print heads and deposited onto a manufacturing tray as continuous layers according to a predetermined configuration defined by a software file.

[0016] Synthetic rubber is typically made from artificial elastomers. Elastomers are viscoelastic polymers that generally have a lower Young's modulus and a higher yield strain compared to other materials. Because elastomers are typically amorphous polymers that exist at temperatures above their glass transition temperature (Tg), they allow for considerable segmentation. Therefore, at room temperature, rubber is relatively soft, has an elasticity of about 3 MPa, and is deformable.

[0017] Elastomers are typically thermosetting polymers (or copolymers) that require curing (vulcanization) to crosslink the polymer chains. A commonly used polymer is polybutadiene. Elasticity arises from the ability of long molecular chains to reconfigure themselves and distribute applied stress. Covalent crosslinking ensures that the elastomer returns to its original configuration when the stress is removed. Elastomers typically exhibit reversible elongation in the range of 5% to 700%.

[0018] Rubber typically contains fillers and reinforcing agents to increase its hardness. The most common reinforcing agents include finely divided carbon black and / or fine silica.

[0019] Both carbon black and silica, when added to polymer mixtures during rubber manufacturing at a concentration of typically around 30% by volume, increase the elastic modulus of the rubber by two to three times, and also impart significant toughness, particularly abrasion resistance, to typically weaker materials. Adding large amounts of carbon black or silica particles further improves the elastic modulus, but may decrease tensile strength.

[0020] Additive manufacturing processes have been used to form rubber-like materials. For example, rubber-like materials are used in the PolyJet® system described herein. These materials have relatively low viscosity, enabling, for example, inkjet ejection, and are formulated to exhibit a Tg below room temperature, e.g., below -10°C. The latter property (low Tg below room temperature) is achieved by formulating products with a relatively low degree of crosslinking and using monomers or oligomers (e.g., acrylic elastomers) that have an inherently flexible molecular structure.

[0021] An exemplary family of rubber-like materials usable with the PolyJet® system (marketed under the trade name "Tango" family) exhibits a variety of elastomer properties in the resulting cured materials, including Shore A hardness scale, elongation at break, tear resistance, and tensile strength. The softest material in this family has a Shore A hardness of 27.

[0022] Another family of rubber-like materials usable with the PolyJet® system (marketed under the trade name "Agilus" family) is described in PCT international application IL2017 / 050604 (published as international publication 2017 / 208238) by the assignee of this application, and utilizes elastomer-curable materials and silica particles.

[0023] Furthermore, the assignee of this application's International Publication No. 2022 / 264139 describes formulations based on curable monofunctional and polyfunctional elastomer materials, combined with a curable polyfunctional non-elastomer material and a curable material containing at least two hydrogen bond-forming groups, which can be used to provide rubber-like materials that meet process requirements in a 3D inkjet printing system equipped with an LED light source as the curing energy source.

[0024] International Publication No. 2022 / 024114 describes a system for three-dimensional printing. This system comprises a nozzle array for extruding printing material, a work tray, a jig for securing fabric to the work tray, and a computerized control unit for controlling the nozzle array to extrude printing material onto the secured fabric. An imaging system can be positioned to image the fabric placed on the work tray, and the image data received from the imaging system can be processed to identify patterns on the fabric, and the nozzles extrude printing material to selected positions relative to the identified patterns.

[0025] The rubbery material is useful for many modeling applications. For example, display models and communication models, rubber exterior members and overmolding, soft-touch coatings and anti-slip surfaces for tools and prototypes, and modeling applications such as knobs, grips, handles, handles, gaskets, seals, hoses, footwear, etc.

[0026] Additional background art includes U.S. Patent No. 9,227,365, U.S. Patent No. 6,242,149, U.S. Patent Application Publication No. 2010 / 0140850, International Publication No. 2009 / 013751, International Publication No. 2016 / 063282, International Publication No. 2016 / 125170, International Publication No. 2017 / 134672, International Publication No. 2017 / 134673, International Publication No. 2017 / 134674, the same v2017 / 134676, International Publication No. 2017 / 068590, International Publication No. 2017 / 187434, International Publication No. 2018 / 055521, International Publication No. 2018 / 055522, and International Publication No. 2020 / 065654, all of which are by the assignee of the present application.

Summary of the Invention

[0027] According to one aspect of some embodiments of the present invention, there is provided a curable composition that provides an elastomeric material having a resilience (EDE) of 40% or more when cured, the composition comprising at least one monofunctional elastomeric curable material and / or at least one polyfunctional elastomeric curable material, and optionally at least one of a monofunctional non-elastomeric curable material, a polyfunctional non-elastomeric curable material, and a curable material containing two or more hydrogen-bond-forming groups, and at least one polymeric silicone material having an average molecular weight of less than 6000 g / mol and contained in an amount of 5% to 20% by weight based on the total weight of the curable composition.

[0028] According to some of any of the embodiments described herein, the cured elastomeric material has an elongation at break of 100% or more, or 120% or more, or 180% or more, and / or a tensile strength of 1.5 MPa or more, or 1.8 MPa or more, or 2 MPa or more.

[0029] According to some of the embodiments described herein, the curable polymer silicone material is an amphiphilic material.

[0030] According to some of the embodiments described herein, the polymeric silicone material comprises at least one curable polymeric silicone material and / or at least one non-curable polymeric silicone material.

[0031] According to some of the embodiments described herein, the curable polymer silicone material is a bifunctional polymer silicone material.

[0032] According to some of the embodiments described herein, the curable polymer silicone material has one or more (meth)acrylate curable groups.

[0033] According to some of the embodiments described herein, the curable polymeric silicone material comprises a silicone polyester di(meth)acrylate.

[0034] According to some of the embodiments described herein, the curable polymer silicone material has one or more urethane (meth)acrylate curable groups.

[0035] According to some of the embodiments described herein, the curable polymeric silicone material comprises a silicone diurethane (meth)acrylate.

[0036] According to some of the embodiments described herein, the non-curable polymeric silicone material includes a silicone polyether.

[0037] According to some of the embodiments described herein, the polymeric silicone material comprises at least one curable polymeric silicone material and at least one non-curable polymeric silicone material.

[0038] According to some of the embodiments described herein, the weight ratio of at least one curable polymeric silicone material to at least one non-curable polymeric silicone material is in the range of 5:1 to 1:5, or 2:1 to 1:2.

[0039] According to some of the embodiments described herein, the elastomer material is a hydrophilic elastomer material.

[0040] According to some of the embodiments described herein, the polymeric silicone material comprises at least one curable polymeric silicone material in an amount of 5% to 10% by weight relative to the total weight of the curable compound.

[0041] According to some of the embodiments described herein, the polymeric silicone material comprises at least one non-curable polymeric silicone material in an amount of 5% by weight or less relative to the total weight of the curable compound.

[0042] According to some of the embodiments described herein, the cured hydrophilic material further comprises silica particles, and the polymeric silicone material comprises at least one curable polymeric silicone material in an amount of 5% by weight or less relative to the total weight of the curable compound.

[0043] According to some of the embodiments described herein, the cured elastomer material is a hydrophobic elastomer material.

[0044] According to some of the embodiments described herein, the polymeric silicone material comprises at least one non-curable polymeric silicone material in an amount of 1% to 10% by weight, or 2% to 10% by weight, or 5% to 10% by weight, preferably 5% by weight, relative to the total weight of the curable compound.

[0045] According to some of the embodiments described herein, the polymeric silicone material comprises at least one non-curable polymeric silicone material and at least one curable polymeric silicone material.

[0046] According to some of the embodiments described herein, the weight ratio of at least one curable polymeric silicone material to at least one non-curable polymeric silicone material is in the range of 5:1 to 1:5 or 2:1 to 1:2, preferably in the range of 5:1 to 1:1 or 2:1 to 1:1.

[0047] According to one aspect of several embodiments of the present invention, a method is provided for additively manufacturing a three-dimensional object comprising, at least in part, an elastomer material, the method comprising sequentially forming a plurality of layers in a configuration pattern corresponding to the shape of the object, thereby forming the object, the formation of at least a portion of the plurality of layers comprising, in any one of the embodiments and any combination thereof, extruding a curable compound described herein as a modeling material compound, and exposing the extruded modeling material to curing energy to form a cured modeling material, thereby manufacturing a three-dimensional object.

[0048] According to some of the embodiments described herein, the curing energy includes UV irradiation.

[0049] According to one aspect of several embodiments of the present invention, a three-dimensional object is provided which is manufactured by the method described herein and comprises at least a portion thereof a cured elastomer material.

[0050] Unless otherwise defined, all technical and / or scientific terms used herein have the same meaning as those commonly understood by those skilled in the art relating to the present invention. Methods and materials similar to or equivalent to those described herein may be used to carry out or test embodiments of the present invention, but exemplary methods and / or materials are described below. In case of any conflict, the patent specification, including definitions, shall prevail. Furthermore, materials, methods, and examples are for illustrative purposes only and are not necessarily intended to limit the scope of the invention.

[0051] Implementation of the methods and / or systems of embodiments of the present invention may include performing or completing selected tasks manually, automatically, or in combination thereof. Furthermore, according to actual equipment and apparatus of embodiments of the methods and / or systems of the present invention, a selection of tasks can be implemented using an operating system by hardware, software, firmware, or a combination thereof.

[0052] For example, hardware for performing selected tasks according to embodiments of the present invention may be implemented as a chip or circuit. As software, selected tasks according to embodiments of the present invention may be implemented as a set of software instructions executed by a computer using any suitable operating system. In exemplary embodiments of the present invention, one or more tasks according to exemplary embodiments of the method and / or system described herein are performed by a data processor, such as a computing platform, for executing a set of instructions. Optionally, the data processor includes volatile memory for storing instructions and / or data, and / or non-volatile storage, such as a magnetic hard disk and / or removable media, for storing instructions and / or data. Optionally, network connectivity is also provided. A display and / or a user input device, such as a keyboard or mouse, is also optionally provided.

[0053] Several embodiments of the present invention are described herein, with reference to the accompanying drawings, for illustrative purposes only. While the drawings are referenced in particular here, it is emphasized that the details shown are illustrative and intended to illustrate embodiments of the present invention. In this regard, the description with reference to the drawings will make it clear to those skilled in the art how embodiments of the present invention may be carried out. [Brief explanation of the drawing]

[0054] [Figure 1A]This is a schematic diagram of an additive manufacturing system according to several embodiments of the present invention. [Figure 1B] This is a schematic diagram of an additive manufacturing system according to several embodiments of the present invention. [Figure 1C] This is a schematic diagram of an additive manufacturing system according to several embodiments of the present invention. [Figure 1D] This is a schematic diagram of an additive manufacturing system according to several embodiments of the present invention. [Figure 2A] This is a schematic diagram of a print head according to several embodiments of the present invention. [Figure 2B] This is a schematic diagram of a print head according to several embodiments of the present invention. [Figure 2C] This is a schematic diagram of a print head according to several embodiments of the present invention. [Figure 3A] This is a schematic diagram illustrating coordinate transformations according to several embodiments of the present invention. [Figure 3B] This is a schematic diagram illustrating coordinate transformations according to several embodiments of the present invention. [Figure 4] Table 2 shows comparative plots illustrating the tensile strength as a function of elongation, determined by repeated stress-strain measurements, for the formulations shown. [Figure 5] Table 4 shows comparative plots illustrating the tensile strength as a function of elongation, determined by repeated stress-strain measurements, for the formulations shown. [Modes for carrying out the invention]

[0055] In some embodiments, the present invention relates to three-dimensional printing, and more specifically, but not limited to, to formulations usable for additive manufacturing of three-dimensional objects, providing elastomer (rubber-like) materials characterized by improved resilience, and methods / processes utilizing the same.

[0056] Before describing in detail at least one embodiment of the present invention, it should be understood that in its application, the present invention is not necessarily limited to the structural and arrangement details of the components and / or methods described below and / or illustrated in the drawings and / or embodiments. Other embodiments of the present invention are possible, or it can be carried out or implemented in a variety of ways.

[0057] In the conventional manufacturing of elastomer materials (elastomers, rubber-like materials), the starting material is usually a thermoplastic polymer with a low Tg, which is then kneaded and cured or vulcanized to obtain the desired final properties. In contrast, in additive manufacturing processes such as 3D (inkjet) printing, a cured polymer is produced in a single step from suitable monomers and / or low molecular weight (e.g., less than 1,000 g / mol or less than 500 g / mol) crosslinking agents and oligomers. Therefore, it is difficult to control the molecular weight, crosslinking density, and mechanical properties of rubber-like materials obtained through such processes. Consequently, PolyJet® rubber-like materials, for example, often exhibit characteristics such as low tear resistance (TR) and slow recovery speed after deformation (low resilience (EDE)) compared to conventional elastomers. PolyJet® rubber-like materials that exhibit high elongation are often characterized by low elastic modulus, low tear resistance, and / or low Tg and tackiness.

[0058] The inventors have now designed and successfully commercialized novel formulations that are suitable for use in additive manufacturing (for example, possessing properties that meet the AM process requirements described herein) and provide a rubber-like material upon curing. These novel formulations include an elastomeric curable material (and optionally a non-elastomeric curable material) as well as a silicone-containing polymer material that imparts improved resilience to the cured material while minimizing adverse effects on other mechanical properties.

[0059] Throughout this specification, the terms “rubber,” “rubbery materials,” “elastomer materials,” and “elastomer” are used interchangeably to describe materials characterized by elastomer properties. The terms “rubbery-like material” or “rubber-like material” are used to describe materials characterized by rubber properties that are produced by additive manufacturing (e.g., 3D inkjet printing) rather than by conventional processes involving the vulcanization of thermoplastic polymers. These terms are used to describe materials obtained by curing or solidifying the formulations described herein.

[0060] The term "rubber-like material" is also interchangeably referred to as "elastomer material" in this specification.

[0061] Elastomers or rubbers are flexible materials typically characterized by a low Tg (for example, lower than room temperature, preferably lower than 10°C, lower than 0°C, and even lower than -10°C).

[0062] The following describes some of the characteristic properties of rubber-like materials used in this specification and in the art.

[0063] Shore A hardness, also known as Shore hardness or simply hardness, is defined by a Type A durometer scale and represents a material's resistance to permanent indentation. Shore hardness is typically measured based on ASTM D2240.

[0064] The elastic modulus, also known as the modulus of elasticity, Young's modulus, tensile modulus, or simply "E," represents a material's resistance to elastic deformation when a force is applied. In other words, it describes the tendency of an object to deform along an axis when opposing forces are applied along that axis. The elastic modulus is typically measured by a tensile test (e.g., according to ASTM D624) and is determined by the linear slope of the stress-strain curve in the elastic deformation region. Here, "stress" is the force causing the deformation divided by the area over which the force is applied, and "strain" is the ratio of the change in the length parameter caused by the deformation to the original value of the length parameter. Stress is proportional to the tensile force applied to the material, and strain is proportional to the length of the material.

[0065] Tensile strength represents a material's resistance to tension, or in other words, its ability to withstand a load attempting to stretch it, and is defined as the maximum stress (MPa) applied to an elastomer composite before it fractures when stretched. Tensile strength is typically measured by a tensile test (e.g., according to ASTM D624) and determined as the peak of the stress-strain curve, as described herein and in the Art.

[0066] Elongation, or elongation at break, is the elongation of a uniform portion of a material and is expressed as a percentage of its original length, as shown in the formula below.

[0067] JPEG2026511895000002.jpg1896

[0068] Elongation, or elongation at break, is typically measured according to ASTM D412.

[0069] Z-tensile elongation is the elongation measured by the method described herein during printing in the Z-direction.

[0070] Tear resistance (TR), also known as "tear strength" in this specification and the art, is expressed in N / mm or Kg / cm as the maximum force required to tear a material, and this force acts approximately parallel to the long axis of the sample. Tear resistance can be measured by the ASTM D412 method. ASTM D624 can be used to measure resistance to tear formation (initiation of tearing) and resistance to tear propagation (propagation of tearing). Typically, the sample is held between two holders and a uniform tensile force is applied until deformation occurs. Tear resistance is calculated by dividing the applied force by the thickness of the material. Materials with low tear resistance tend to have poor abrasion resistance.

[0071] Tear resistance under constant elongation represents the time required for a test specimen to fracture when subjected to a constant elongation (less than the elongation at fracture). This value is determined, for example, by an "O-ring" test as described in International Publication No. 2017 / 208238.

[0072] Resilience, also known herein as Energy dissipation Efficiency (EDE), represents the ability of a material to return to its original shape after temporary deformation. Resilience can be determined according to the methods described in the following Examples section. In exemplary embodiments, resilience is determined based on repeated strain-strain curves according to the respective equations shown in the following Examples section.

[0073] Embodiments of the present invention relate to formulations usable for additive manufacturing of three-dimensional (3D) objects or parts thereof made of rubber-like materials, additive manufacturing processes utilizing the same, and objects manufactured by these processes.

[0074] Throughout this specification, the term “object” refers to the final product obtained by additive manufacturing. This term refers to the product obtained by the methods described herein, and, if a support material is used as part of the modeling material, the product obtained after the support material has been removed. Thus, “object” consists essentially of a modeling material that is hardened (e.g., cured) (at least 95% by weight).

[0075] As used throughout this specification, the term “object” refers to a three-dimensional object as a whole or a part thereof.

[0076] An object according to this embodiment is formed in part or portion of a rubber-like material, and is also referred to herein as an "object formed of a rubber-like material." An object may have several parts or portions formed from a rubber-like material, or the entire object may be formed from a rubber-like material. The rubber-like materials used in different parts or portions may be the same or different, and the rubber-like materials used in each part, portion, or entire object formed from a rubber-like material may be the same or different. When different rubber-like materials are used, their chemical composition and / or mechanical properties may differ, as will be further described below.

[0077] Throughout this specification, terms such as “building material formulation,” “uncured building material,” “uncured building material formulation,” and “building material,” and other variations thereof, refer collectively to materials extruded to sequentially form layers, as described herein. These terms include uncured materials extruded to form an object, i.e., one or more uncured modeling material formulations, and uncured materials extruded to form a support structure, i.e., uncured support material formulations.

[0078] Throughout this specification, the terms "cured modeling material" or "hardened modeling material" refer to the portion of the modeling material formed by curing the extruded modeling material, which forms an object as defined herein, and further, if optionally a support material is extruded, the portion that forms an object after the hardened support material has been removed. The hardened modeling material may be a single cured material or a mixture of two or more cured materials, depending on the modeling material formulation used in this method, as described herein.

[0079] The terms "cured modeling material" or "cured modeling material formulation" can be interpreted as a cured modeling material consisting solely of the modeling material formulation (without any support material formulation). In other words, this term refers to the portion of the modeling material used to produce the final object.

[0080] Throughout this specification, the term “modeling material formulation” is interchangeably referred to as “modeling formulation,” “model formulation,” “modeling material formulation,” or simply “formulation,” and refers to a portion or all of the molding material extruded to form an object, as described herein. A modeling material formulation is (unless otherwise specified) an uncured modeling formulation which, when exposed to curing energy, forms an object or a portion thereof.

[0081] In some embodiments of the present invention, the modeling material formulation is formulated for use in three-dimensional inkjet printing and can form three-dimensional objects on its own, i.e., without being mixed or combined with other materials.

[0082] The uncured molding material may contain one or more modeling formulations, and upon curing, it may be extruded such that different parts of the object are composed of different cured modeling formulations or different combinations thereof. Thus, different parts of the object may be formed from different cured modeling materials or different mixtures of cured modeling materials.

[0083] The formulations that form the modeling material (modeling material formulations and support material formulations) include one or more curable materials that, when exposed to curing energy, form a hardened (cured) material.

[0084] Formulations that form the molding material (modeling material formulations and support material formulations) are also referred to herein as curable formulations (e.g., curable modeling material formulations or curable support material formulations).

[0085] Throughout this specification, “curable material” means a compound that, when exposed to curing conditions (e.g., curing energy), solidifies or hardens to form a curable material (usually a monomer or oligomer compound, but optionally a polymer material). Curable materials are typically polymerizable materials that undergo polymerization and / or crosslinking when exposed to a suitable energy source.

[0086] According to this embodiment, the curable material also includes materials that harden or solidify (i.e., cure) without being exposed to curing energy, but rather by exposure to other curing conditions (e.g., exposure to chemical reagents, or simply exposure to the environment).

[0087] The terms "curable" and "solidifiable" as used herein are interchangeable.

[0088] Polymerization can be, for example, free radical polymerization, cationic polymerization, or anionic polymerization, each of which can be induced by exposure to a curing energy such as radiation or heat, as described herein.

[0089] In some of the embodiments described herein, the curable material is a photopolymerizable material that polymerizes and / or crosslinks upon exposure to radiation as described herein, and in some embodiments, the curable material is a UV-curable material that polymerizes and / or crosslinks upon exposure to UV radiation as described herein.

[0090] In some embodiments, the curable material described herein is a photopolymerizable material polymerized by photo-induced free radical polymerization. Alternatively, the curable material is a photopolymerizable material polymerized by photo-induced cationic polymerization.

[0091] In some of the embodiments described herein, the curable material may be a monomer, oligomer, or short-chain polymer, each of which is polymerizable and / or crosslinkable as described herein.

[0092] In some of the embodiments described herein, when a curable material is exposed to curing energy (e.g., radiation), it hardens (i.e., cures) by either chain extension and / or crosslinking, or a combination thereof.

[0093] In some of the embodiments described herein, the curable material is a monomer or mixture of monomers that, when exposed to a curing energy at which polymerization occurs, can form a polymer material by polymerization. Such a curable material is also referred to herein as a “monomer curable material”.

[0094] In some of the embodiments described herein, the curable material is an oligomer or mixture of oligomers that, when exposed to curing energy at which a polymerization reaction occurs, can form a polymer material by polymerization. Such a curable material is also referred to herein as an "oligomeric curable material".

[0095] In some of the embodiments described herein, the curable material may be a "monofunctional curable material" or a "polyfunctional curable material," whether it is a monomer or an oligomer.

[0096] In this specification, "monofunctional curable material" comprises one functional group that can undergo polymerization when exposed to curing energy (e.g., radiation).

[0097] A "polyfunctional curable material" contains two or more functional groups, for example, two, three, or four or more, that can polymerize when exposed to curing energy. A polyfunctional curable material may be, for example, a difunctional, trifunctional, or tetrafunctional curable material, which each contains two, three, or four polymerizable groups (also expressed herein as being characterized by a functionality such as 2, 3, or 4). Two or more functional groups in a polyfunctional curable material are usually linked to each other by linkers, as defined herein. If the linkers are oligomers or polymer linkers, the polyfunctional group is an oligomer or polymer polyfunctional curable material. A polyfunctional curable material can polymerize and / or act as a crosslinking agent when subjected to curing energy.

[0098] The method of this embodiment, as described herein, manufactures a three-dimensional object in layers by forming multiple layers with configured patterns corresponding to the shape of the object.

[0099] The final three-dimensional object is fabricated from a modeling material, a combination of modeling materials, a combination of modeling materials and support materials, or a modified version thereof (e.g., after curing). All of these operations are well known to those skilled in solid freeform fabrication.

[0100] According to one aspect of several embodiments of the present invention, a method for additive manufacturing a three-dimensional object made of the elastomer (rubber-like) material described herein is provided.

[0101] This method is generally carried out by sequentially forming multiple layers in a configuration pattern corresponding to the shape of an object, wherein the formation of at least a portion of each of the multiple layers, or each of the multiple layers, includes extruding an uncured molding material containing one or more modeling material formulations and optionally a support material formulation, and exposing the extruded modeling material formulations and optionally a support material formulation to curing conditions (e.g., curing energy). This results in the formation of cured modeling material and optionally cured support material. This will be described in more detail below.

[0102] In some exemplary embodiments of the present invention, an object is manufactured by extruding a modeling material (uncured) comprising two or more different modeling material formulations, where each modeling material formulation is extruded from a different nozzle array of an inkjet printer. The modeling material formulations are optionally and preferably deposited in layers within the same pass of the print head. The modeling material formulations and / or combinations of formulations within the layers are selected according to the desired properties of the object, and are described in further detail below.

[0103] As used herein and in the art, the term “digital material” refers to a combination of two or more materials at a microscopic or voxel level, such that the printed area of ​​a particular material is at the level of a few voxels or at the level of a single voxel block. Such digital materials may exhibit novel properties influenced by the choice of material types and / or the ratio and relative spatial distribution of two or more materials.

[0104] In exemplary digital materials, the modeling material of each voxel or voxel block obtained during curing is independent of the modeling material of adjacent voxels or voxel blocks obtained during curing, and each voxel or voxel block may have a different modeling material, and the new properties of the entire part are the result of the spatial combination of multiple different modeling materials at the voxel level.

[0105] Throughout this specification, whenever the expression “at the voxel level” is used in the context of different materials and / or properties, it means that it includes not only differences between voxel blocks but also differences between voxels or between groups of voxels. In a preferred embodiment, the properties of the entire part are the result of spatially combining several different modeling materials at the voxel block level.

[0106] <Curing elastomer compound> According to one aspect of several embodiments of the present invention, a curable compound is provided that, upon curing, provides an elastomer material. According to this embodiment, the curable compound is designed to provide an elastomer material, upon curing, having an EDE (Education Determination) of 40% or more, preferably 50% or more, or 60% or more, or 70% or more, as described, defined, and measured herein.

[0107] As used throughout this specification and as described above, elastomer cured materials are typically further characterized by one or more of the following:

[0108] The tear resistance is 4 kg / cm or more, or 4.5 kg / cm or more, for example, 4 kg / cm to 8 kg / cm, or 4 kg / cm to 7.5 kg / cm, or 4.5 kg / cm to 8 kg / cm, or 4.5 kg / cm to 7.5 kg / cm (including any intermediate values ​​and sub-ranges).

[0109] The tensile strength is 2 MPa or more, or 2.5 MPa or more, for example, 2 MPa to 6 MPa, or 2 MPa to 5 MPa, or 2 MPa to 3 MPa, or 2 MPa to 4 MPa, or 3 MPa to 5 MPa (including any intermediate values ​​and sub-ranges thereof).

[0110] The elongation at break is 300% or more, or 350% or more, for example, 300% to 500%, or 300% to 450%, or 300% to 400%, or 350% to 500%, or 350% to 450%, or 350% to 400% (including any intermediate values ​​and sub-ranges).

[0111] The Shore A hardness is 30 or greater, or 40 or greater, for example, 30-50, or 30-40, or 35-50, or 40-50, or 35-45 (including any intermediate values ​​and sub-ranges).

[0112] The Tg (e.g., average Tg) is 15°C or lower, or 10°C or lower, or 5°C or lower, or 0°C or lower, or 10°C or higher, 15°C or higher, or 20°C or higher than the temperature of the additive manufacturing system described herein.

[0113] According to some of the embodiments described herein, the curable elastomer formulation provides a curable material characterized by one, two, three, four or all of the above properties.

[0114] According to some of the embodiments described herein, as described in the Examples section below, the elastomer curable formulations of these embodiments are further characterized by good printability and stability, and when used in additive manufacturing, provide objects with minimal deformation, warping and / or volume shrinkage.

[0115] According to some of the embodiments described herein, the curable formulation has one or more of the above properties when cured by exposure to irradiation (electromagnetic curing energy) as a curing condition. In some embodiments, it has one or more of the above properties when cured by exposure to irradiation in the UV-visible range, and in some of these embodiments, it has one or more of the above properties when cured by exposure to UV irradiation from an LED light source.

[0116] According to some of the embodiments described herein, a curable compound has one or more of the above properties when cured by exposure to irradiation (electromagnetic curing energy) as a curing condition at a temperature of 40°C or less, or 35°C or less. In some of these embodiments, the irradiation is UV irradiation from an LED light source.

[0117] The curable formulations described herein are also referred to herein as elastomer formulations or curable elastomer formulations, and are preferably used as modeling material formulations described herein.

[0118] According to some of the embodiments described herein, the curable formulation comprises one or more curable materials, at least one of which is an elastomer curable material. According to some embodiments, the curable formulation comprises one or more monofunctional elastomer curable materials and / or one or more polyfunctional elastomer curable materials. The curable formulation may optionally further comprise one or more non-elastomer materials, for example, one or more of a monofunctional non-elastomer curable material, a polyfunctional non-elastomer curable material, a curable material containing at least two hydrogen bond-forming groups, and silica particles. Examples of these non-elastomer materials are, for example, those described in International Publication No. 2017 / 208238, which is incorporated herein by reference as if described in whole.

[0119] The curable material constituting the elastomer curable compound can be selected to provide a hydrophobic or hydrophilic elastomer material when cured, as will be described in more detail herein.

[0120] According to this embodiment, the curable compound comprises one or more polymeric silicone materials, which are interchangeably referred to herein as silicone-containing polymeric materials.

[0121] According to some of the embodiments described herein, the total amount of one or more polymeric silicone materials is in the range of 5% to 20% by weight relative to the total weight of the formulation (including any intermediate and sub-ranges thereto).

[0122] According to some of the embodiments described herein, the total amount of one or more polymeric silicone materials is in the range of 5% to 10% by weight relative to the total weight of the formulation (including any intermediate and sub-ranges thereto).

[0123] According to some of the embodiments described herein, the total amount of one or more polymeric silicone materials is in the range of 5% to 15% by weight relative to the total weight of the formulation (including any intermediate and sub-ranges thereto).

[0124] According to some of the embodiments described herein, the total amount of one or more polymeric silicone materials is in the range of 1% to 20% by weight relative to the total weight of the formulation (including any intermediate and sub-ranges thereto).

[0125] According to some of the embodiments described herein, the total amount of one or more polymeric silicone materials is in the range of 1% to 10% by weight relative to the total weight of the formulation (including any intermediate and sub-ranges thereto).

[0126] According to some of the embodiments described herein, the total amount of one or more polymeric silicone materials is in the range of 5% to 10% by weight relative to the total weight of the formulation (including any intermediate and sub-ranges thereto).

[0127] According to some of the embodiments described herein, each of the one or more silicone-containing polymer materials independently has a relatively low average molecular weight (MW), i.e., less than 8,000 grams / mol, preferably less than 6,000 grams / mol, preferably between 500 grams / mol and 8,000 grams / mol, or between 500 grams / mol and 7,000 grams / mol, or between 50 grams / mol and 6,000 grams / mol, or between 1,000 grams / mol and 8,000 grams / mol, or between 1,000 grams / mol and 7,000 grams / mol. The range is 1,000 g / mol to 6,000 g / mol, or 1,000 g / mol to 5,000 g / mol, or 2,000 g / mol to 8,000 g / mol, or 2,000 g / mol to 7,000 g / mol, or 2,000 g / mol to 6,000 g / mol, or 2,000 g / mol to 5,000 g / mol, or 1,000 g / mol to 5,000 g / mol, or 3,000 g / mol to 6,000 g / mol (including any intermediate values ​​and sub-ranges).

[0128] The silicone-containing polymer material comprises the silicone described herein, for example, polydimethylsiloxane (PDMS), wherein one or more of its terminals are modified and / or one or more of its Si atoms are substituted. If the silicone-containing polymer material is modified or substituted with polymer moieties, the material is considered a copolymer. If the silicone-containing polymer material is modified or substituted with moieties containing one or more curable groups, the material is considered a curable material.

[0129] According to some of the embodiments described herein, at least one, more preferably one or more, silicone-containing polymer materials is an amphiphilic material as defined herein.

[0130] According to some of the embodiments described herein, the polymeric silicone material comprises one or more curable polymeric silicone materials and / or one or more non-curable polymeric silicone materials.

[0131] According to some of the embodiments described herein, the curable polymeric silicone material may be a monofunctional or polyfunctional polymeric silicone material.

[0132] According to some embodiments, the curable polymer silicone material is a polyfunctional curable material, preferably a bifunctional curable polymer silicone material.

[0133] According to some of the embodiments described herein, the curable polymer silicone material is a UV-curable material characterized by one or more, preferably two, UV-curable groups as described herein. In some embodiments, the curable polymer silicone material comprises one or more, preferably two (meth)acrylic (e.g., (meth)acrylate) curable groups.

[0134] According to some of the embodiments described herein, the curable polymeric silicone material comprises two (meth)acrylate curable groups, is an amphiphilic material, and is characterized by the average molecular weight (MW) described herein.

[0135] Examples of such materials include, for example, the silicone polyester (meth)acrylate described herein, such as silicone polyester di(meth)acrylate, also known herein as silicone A. Another example of such material is the bifunctional silicone urethane (meth)acrylate (silicone urethane di(meth)acrylate), also known herein as silicone B. Examples of such commercially available materials include those sold under the trade names "SIP910" and "SIU100".

[0136] Other examples include silicone di(meth)acrylates such as those sold as "Silmer® ACRDi2510," "Silmer ACR® Di1010," and "Silmer® ACR Di1508." Other materials with the above characteristics are also conceivable.

[0137] The non-curing silicone-containing material may contain silicone alone, but preferably contains silicone in which one or more of its ends are modified by an amphiphilic moiety and / or one or more of its Si atoms are substituted by an amphiphilic moiety. In some embodiments, the amphiphilic moiety is a polymer moiety, and the silicone-containing polymer material is a copolymer.

[0138] In exemplary embodiments, the non-curable silicone is a silicone polyether containing one or more polyether moieties bonded to one or more of its ends, which is also referred to herein as silicone NR. In exemplary embodiments, the polyether is poly(alkylene glycol) as defined herein, for example, poly(ethylene glycol). One or more polyether moieties in the silicone polyether may independently contain 2, 3, 4, 5, 6, 7, preferably 8, 9, 10, or more alkylene glycol units, as long as the average molecular weight is as defined herein. Exemplary silicone polyethers usable as non-curable silicone-containing polymer materials are commercially available under the trade name "Silsurf®", such as "Silsurf® A010-D and Silsurf® C208". Other materials are also envisioned.

[0139] The elastomer compound according to this embodiment may include one type of silicone-containing polymer material, or a combination of one or more silicone-containing polymer materials.

[0140] According to some of the embodiments described herein, the formulation comprises one or more curable polymeric silicone materials and one or more non-curable polymeric silicone materials, each as described herein in any of the respective embodiments and any combination thereof.

[0141] According to some of these embodiments, the weight ratio of one or more curable polymeric silicone materials to one or more non-curable polymeric silicone materials is in the range of 5:1 to 1:5, or 4:1 to 1:4, or 3:1 to 1:3, or 2:1 to 1:2 (including any intermediate and sub-ranges thereof).

[0142] The type and amount of silicone-containing polymer material, and the weight ratio when combining two or more materials, can be determined according to the elastomer compound containing the silicone-containing polymer material.

[0143] Generally, elastomer curable formulations may be formulations that provide a cured elastomer material that can be hydrophilic or hydrophobic after curing, as described herein.

[0144] According to some embodiments, the elastomer formulation provides a hydrophilic elastomer material upon curing, and the polymeric silicone material comprises at least one curable polymeric silicone material according to any embodiment described herein in an amount ranging from 5% to 10% by weight (including any intermediate and sub-ranges) relative to the total weight of the formulation.

[0145] According to some embodiments, the elastomer formulation provides a hydrophilic elastomer material upon curing. According to some of these embodiments, the polymeric silicone material includes at least one non-curable polymeric silicone material according to any embodiment described herein in an amount of 5% by weight or less, for example, in the range of 1% to 5% by weight, or 2% to 5% by weight (including any intermediate and sub-ranges thereof), based on the total weight of the formulation.

[0146] A compound marketed by the assignee of this application under the trademark "Elastico®" is an example of such an elastomer compound. An example of an elastomer compound is described in International Publication No. 2022 / 264139, which is incorporated herein by reference as if it were described in its entirety.

[0147] An example of an elastomer formulation is described in the Examples section below, which includes monofunctional and polyfunctional elastomer curable materials in combination with a polyfunctional non-elastomer curable material and a curable material containing at least two hydrogen bond-forming groups.

[0148] According to some embodiments, the elastomer formulation provides a hydrophilic elastomer material upon curing and further includes silica particles. According to some of these embodiments, the polymeric silicone material includes at least one curable polymeric silicone material in an amount of 5% by weight or less of the total weight of the formulation, for example, in the range of 1% to 5% by weight, or 2% to 5% by weight (including any intermediate and sub-ranges thereof).

[0149] According to some of the embodiments described herein, an example of a hydrophilic formulation is sold by the assignee under the trade name "Agilus30®".

[0150] An example of such a hydrophilic formulation is described in International Publication No. 2017 / 208238, which is incorporated herein by reference as if it were described in whole.

[0151] According to some embodiments, the elastomer formulation provides a hydrophobic elastomer material upon curing, and the polymeric silicone material comprises at least one non-curable polymeric silicone material in an amount ranging from 1% to 10% by weight, or 2% to 10% by weight, or 5% to 10% by weight (including any intermediate and sub-ranges) relative to the total weight of the formulation. In an exemplary embodiment, the amount of at least one non-curable polymeric silicone material is 5% by weight relative to the total weight of the formulation.

[0152] According to some embodiments, the elastomer formulation provides a hydrophobic elastomer material upon curing, and the polymeric silicone material comprises at least one non-curable polymeric silicone material and at least one curable polymeric silicone material.

[0153] According to some of these embodiments, the weight ratio of at least one curable polymeric silicone material to at least one non-curable polymeric silicone material is in the range of 5:1 to 1:5, or 4:1 to 1:4, or 3:1 to 1:3, or 2:1 to 1:2, preferably in the range of 5:1 to 1:1, or 4:1 to 1:1, or 3:1 to 1:1, or 2:1 to 1:1, and includes any intermediate values ​​and sub-ranges between these.

[0154] As used throughout this specification, the term "hydrophobic" refers to the physical property of a material or part of a material (e.g., a chemical group in a compound) that it does not form bonds with water molecules.

[0155] In the context of cured materials, hydrophobic materials are characterized by low or zero water absorption, for example, water absorption of less than 1%, less than 0.5%, less than 0.1%, less than 0.05%, or even lower. Water absorption can be measured using methods known in the art. Alternatively, hydrophobic cured materials can be determined by comparing the mechanical properties of the material (e.g., tensile strength, Shore A hardness, elongation at break, and / or tear resistance) when the material is stored at room temperature in a dry environment and a wet environment (e.g., immersion in water). If no change of 10% or less, or 5% or less, is observed in at least one property, the cured material is considered hydrophobic.

[0156] According to some of the embodiments described herein, the hydrophobic elastomer compound comprises one or more monofunctional curable materials and one or more polyfunctional curable materials, wherein 80% or more by weight, or 90% or more by weight, of these curable materials is hydrophobic curable material based on the total weight of the compound.

[0157] In the context of curable materials, the term "hydrophobic" refers to the physical property of a material or a part of a material (e.g., a chemical group in a compound) that it does not form bonds with water molecules.

[0158] Hydrophobic materials are more soluble in oil than in water or other hydrophilic solvents. Hydrophobic materials can be identified, for example, by measuring the LogP value in the octanol and aqueous phases at room temperature, where the LogP value is greater than 1.

[0159] Hydrophobic materials can be determined, alternatively or additionally, by having an oleophilic / hydrophilic balance (HLB) of less than 3, according to the Davis method.

[0160] As used throughout this specification, the term "hydrophilic" refers to the physical property of a material or part of a material (e.g., a chemical group in a compound) in which temporary bonds with water molecules are formed, usually via hydrogen bonds.

[0161] In the context of cured materials, hydrophilic materials are characterized by a water absorption rate of 1% or more, or 2% or more, or 5% or more (e.g., 10%, 20%, or more). The water absorption rate can be measured using methods known in the art. Alternatively, hydrophilic cured materials can be determined by comparing the mechanical properties of the material (e.g., tensile strength, Shore A hardness, elongation at break, and / or tear resistance) when the material is stored at room temperature in a dry environment and a wet environment (e.g., immersion in water). If a change of 1.5% or more, or 2% or more, or 5% or more is observed in at least one property, the cured material is considered hydrophilic.

[0162] Hydrophilic materials are more soluble in water than oils or other hydrophobic solvents. Hydrophilic materials can be identified, for example, by measuring the LogP in the octanol phase and aqueous phase at room temperature, with the LogP value being lower than 0.5.

[0163] Hydrophilic materials can be determined, alternatively or additionally, by having an oleophilic / hydrophilic balance (HLB) of 10 or greater, or 12 or greater, according to the Davis method.

[0164] As used throughout this specification, the term "amphiphilic" refers to a property of a material that combines the hydrophilicity described herein for hydrophilic materials and the hydrophobicity or lipophilicity as defined herein for hydrophobic materials.

[0165] Amphiphilic materials typically contain both hydrophilic groups as defined herein and hydrophobic groups as defined herein, and are substantially soluble in both water and water-immiscible solvents (oils).

[0166] Amphiphilic materials can be identified, for example, by having a LogP of 0.8 to 1.2, or about 1, when measured in the octanol phase and aqueous phase at room temperature.

[0167] Amphiphilic materials can be determined, alternatively or additionally, by a lipophilic / hydrophilic balance (HLB) of 3-12 or 3-9 according to the Davis method.

[0168] Hydrophilic materials or parts of materials (for example, chemical groups in a compound) are typically charge-polarized and capable of forming hydrogen bonds.

[0169] Amphiphilic materials typically contain one or more hydrophilic groups (e.g., charged polar groups) in addition to hydrophobic groups.

[0170] Hydrophobic materials or parts of materials (e.g., chemical groups in a compound) are typically nonpolar and cannot form hydrogen bonds.

[0171] Hydrophilic materials or hydrophilic groups, and amphiphilic materials typically contain one or more electron-donating heteroatoms that form strong hydrogen bonds with water molecules. Examples of such heteroatoms, but not limited to, include oxygen and nitrogen. Preferably, the ratio of carbon atoms to heteroatoms in the hydrophilic material or hydrophilic group is 10:1 or less, for example, 8:1, more preferably 7:1, 6:1, 5:1, or 4:1, or less. It should be noted that the hydrophilicity and amphiphilicity of materials and groups can also arise from the ratio of hydrophobic to hydrophilic portions in the material or chemical group, and do not depend solely on the above ratios.

[0172] Hydrophilic or amphiphilic materials may have one or more hydrophilic groups or hydrophilic moieties. Hydrophilic groups are typically polar groups containing one or more electron-donating heteroatoms, such as oxygen or nitrogen.

[0173] Examples of hydrophilic groups include, but are not limited to, electron-donating heteroatoms, carboxylates, thiocarboxylates, oxo(=O), linear amides, hydroxyl, (C1-4) alkoxy, (C1-4) alcohols, alicyclic heterocycles (e.g., those having the carbon-to-heteroatom ratio as defined herein), cyclic carboxylates such as lactones, cyclic amides such as lactams, carbamates, thiocarbamates, cyanurates, isocyanurates, thiocyanurates, ureas, thioureas, alkylene glycols (e.g., ethylene glycol or propylene glycol), and hydrophilic polymers or oligomer moieties (these terms are defined below herein), as well as any combination thereof (e.g., hydrophilic groups comprising two or more of the above-mentioned hydrophilic groups).

[0174] In some embodiments, the hydrophilic group is or comprises an electron-donating heteroatom, a carboxylate, an alicyclic heterocycle, an alkylene glycol, and / or a hydrophilic oligomer moiety.

[0175] The amphiphilic moiety or amphiphilic group may typically contain one or more hydrophilic groups and one or more hydrophobic groups as described herein, or it may be a heteroatom-containing group or heteroatom-containing moiety whose amphiphilicity is defined by the ratio of the number of carbon atoms to the number of heteroatoms.

[0176] Examples of hydrophobic groups include all-carbon groups such as alkyl, alkenyl, alkynyl, aryl, and cycloalkyl groups. Preferably, these groups contain at least four carbon atoms, or at least six carbon atoms, and more preferably, for example, at least eight, nine, ten, or more carbon atoms.

[0177] According to some of the embodiments described herein, the curable elastomer formulation further comprises a non-elastomer curable material, which in some of these embodiments is included in the formulation to adjust the mechanical properties of the curable material when the inclusion of a polymeric silicone material adversely affects the mechanical properties of the curable material.

[0178] According to some embodiments, such non-elastomer curable materials include, for example, hydrogen bond-forming materials, which are collectively referred to as component MA.

[0179] As used herein and as known in the art, a "hydrogen bond" is a non-covalent bond that forms a kind of dipole attraction when a hydrogen atom bonded to a highly electronegative atom is located near another electronegative atom that has a lone pair of electrons.

[0180] In hydrogen bonding, a hydrogen atom is partially shared between two relatively electronegative atoms.

[0181] According to some of the embodiments described herein, the curable material that undergoes crosslinking via hydrogen bonding comprises at least one, preferably at least two, hydrogen bond-forming groups.

[0182] As used herein, the term “hydrogen bond-forming group” refers to a moiety, group, or atom capable of forming hydrogen bonds by acting as a hydrogen bond donor and / or hydrogen bond acceptor. Certain groups can possess both hydrogen bond donor and hydrogen bond acceptor properties, and such groups can cause or establish crosslinking.

[0183] A hydrogen bond donor, also referred to herein as a hydrogen bond forming donor, is a group that contains both an atom to which hydrogen is more strongly bonded and the hydrogen atom itself. On the other hand, a hydrogen bond acceptor, also referred to herein as a hydrogen bond forming acceptor, is an electronegative atom that can bond to the hydrogen atom of another group. A relatively electronegative atom to which a hydrogen atom is covalently bonded attracts electron density from the hydrogen atom, so the hydrogen atom has a partially positive charge (δ + ) it begins to take on a negative charge (δ). Therefore, the hydrogen atom partially takes on a negative charge (δ - It can interact with atoms that have ) through electrostatic interaction.

[0184] Atoms involved in hydrogen bonding interactions as donors or acceptors include oxygen, nitrogen, and fluorine. These atoms typically form part of chemical groups or moieties such as carbonyl, carboxylate, amide, hydroxyl, amine, imine, carbamate, alkyl fluoride, and F2. However, other electronegative atoms, or chemical groups or moieties containing them, can also participate in hydrogen bonding.

[0185] Examples of hydrogen bond-forming groups include, but are not limited to, amides, carboxylates, hydroxyls, alkoxys, aryloxys, ethers, amines, carbamates, hydrazines, nitrogen-containing alicyclic heterocycles (e.g., piperidine, oxalidine), nitriles, and oxygen-containing alicyclic heterocycles (e.g., tetrahydrofuran, morpholine), as well as any other chemical moieties containing one or more nitrogen and / or oxygen atoms.

[0186] According to some of the embodiments described herein, preferred materials are those capable of forming at least two hydrogen bonds by having one or more hydrogen bond-forming groups comprising, for example, two hydrogen donor groups and / or hydrogen acceptor groups.

[0187] In some embodiments, the hydrogen bond-forming curable material comprises one or more hydrogen bond-forming groups selected from amide groups and carbamate groups, each of which is characterized by a hydrogen donor group (-NH-) and a hydrogen acceptor group or atom (=O).

[0188] According to some of the embodiments described herein, preferred materials are those in which at least one hydrogen bond-forming donor is an amine group (e.g., an amine that forms part of an amide or carbamate).

[0189] According to some of the embodiments described herein, preferred materials are those having at least one hydrogen bond donor group and at least one hydrogen bond acceptor group. Preferably, the donor group and the acceptor group are separated from each other by two or fewer atoms, or one or fewer atoms. An exemplary such hydrogen bond forming group is an amide, which may be unsubstituted or substituted with a group that does not contain a hydrogen bond forming group.

[0190] In some embodiments, the hydrogen bond-forming curable material has a ratio of the number of hydrogen bond-forming groups to their molecular weight greater than 0.02, for example, 0.025, 0.030, 0.035, and for example, any of 0.02 to 0.05, or 0.03 to 0.05, or 0.04 to 0.05, or 0.03 to 0.04 (including any intermediate and sub-ranges thereof).

[0191] In some of the embodiments described herein, the hydrogen bond-forming curable material comprises one or more amide groups and, in some embodiments, is (meth)acrylamide (including acrylamide and methacrylamide), preferably methacrylamide. Methacrylamide is preferred because of its low reactivity (lower polymerization rate compared to acrylamide).

[0192] (Meth)acrylamide is preferably unsubstituted. If substituted, the substituent is preferably one that cannot form hydrogen bonds, i.e., one that does not contain a hydrogen bond-forming group as defined herein.

[0193] Alternatively or additionally, the formulation comprises at least one polyfunctional (e.g., trifunctional) ethoxylated material (hereinafter also referred to as component D) having a Tg higher than 50°C or higher than 80°C (e.g., in the range of 80°C to 120°C). In exemplary embodiments, component D comprises an ethoxylated polyfunctional (e.g., trifunctional) material, such as an ethoxylated trifunctional (meth)acrylate, in which case each ethoxylated moiety is a relatively short moiety containing one or two alkylene glycol moieties. Such exemplary materials are marketed under the trade name "SR454".

[0194] Components MA and / or D may be added to the formulation in a total amount ranging from 1% to 10% by weight, or from 1% to 5% by weight (including any intermediate values ​​and sub-ranges) relative to the total weight of the formulation.

[0195] The term "elastomer curable material" as defined herein refers to a curable material that, upon exposure to curing energy, provides a curable material characterized by the properties of an elastomer (rubber or rubber-like material) as described herein and / or known in the art.

[0196] Elastomer curable materials typically consist of one or more polymerizable (curable) groups that undergo polymerization upon exposure to appropriate curing energy, bonded to a moiety that imparts elasticity to the polymerized and / or crosslinked material. Such moieties may typically include alkyl groups, alkylene chains, hydrocarbon groups, alkylene glycol groups or chains (e.g., oligo or poly(alkylene glycol) as defined herein), urethanes, oligourethanes, or polyurethane moieties as defined herein, and any combination thereof. These are also referred to herein as “elastomer moieties.”

[0197] Elastomer curable materials are typically materials that, upon curing, provide a cured material with a Tg of less than 5°C, or less than 0°C, or less than -5°C, for example, in the range of -50°C to 10°C, or -50°C to 0°C, or -50°C to -5°C (including any intermediate values ​​and sub-ranges therein).

[0198] Monofunctional elastomer curable materials according to some embodiments of the present invention may be vinyl-containing compounds represented by formula I.

[0199] [ka]

[0200] In the formula, at least one of R1 and R2 is an elastomer portion as described herein and / or includes such a portion.

[0201] In formula I, the (=CH2) group represents a polymerizable group, and according to some embodiments, this is a UV-curable group, and the elastomer-curable material becomes a UV-curable material.

[0202] For example, R1 is or includes an elastomer portion as defined herein, and R2 is, for example, hydrogen, C(1-4)alkyl, C(1-4)alkoxy, or any other substituent as long as it does not impede the elastomer properties of the cured material.

[0203] In some embodiments, R1 is a carboxylate and the compound is a monofunctional acrylate monomer. In some of these embodiments, R2 is methyl and the compound is a monofunctional methacrylate monomer. Curable materials in which R1 is a carboxylate and R2 is hydrogen or methyl are collectively referred to herein as "(meth)acrylates".

[0204] In some of these embodiments, the carboxylate group (-C(=O)-O-Ra) has an elastomer moiety described herein as Ra.

[0205] In some embodiments, R1 is an amide, and the compound is a monofunctional acrylamide monomer. In some of these embodiments, R2 is methyl, and the compound is a monofunctional methacrylamide monomer. Curable materials in which R1 is an amide and R2 is hydrogen or methyl are collectively referred to herein as "(meth)acrylamide".

[0206] In this specification, (meth)acrylates and (meth)acrylamides are collectively referred to as (meth)acrylic materials.

[0207] In some embodiments, R1 is a cyclic amide, and in some embodiments, R1 is a cyclic amide such as a lactam, and the compound is a vinyl lactam. In some embodiments, R1 is a cyclic carboxylate such as a lactone, and the compound is a vinyl lactone.

[0208] If one or both of R1 and R2 contain a polymer moiety or an oligomer moiety, the monofunctional curable compound of formula I is an exemplary polymer monofunctional curable material or an oligomer monofunctional curable material. Otherwise, it is an exemplary monomer monofunctional curable material.

[0209] In a polyfunctional elastomer material, two or more polymerizable groups are linked to one another via elastomer moieties, as described herein.

[0210] In some embodiments, the polyfunctional elastomer material may be represented by formula I, as described herein, where R1 is an elastomer material terminated with a polymerizable group, as described herein.

[0211] For example, a bifunctional elastomer curable material can be represented by formula I*.

[0212] [ka]

[0213] In the formula, E is an elastomer linkage portion as described herein, and R'2 is as defined herein for R2.

[0214] As another example, a trifunctional elastomer curable material can be represented by formula II.

[0215] [ka]

[0216] In the formula, E is an elastomer linkage portion as described herein, and R'2 and R''2 are each independently defined with respect to R2 as defined herein.

[0217] In some embodiments, polyfunctional (e.g., bifunctional, trifunctional, or more) elastomer curable materials can be collectively represented by formula III.

[0218] [ka]

[0219] In the formula, R2 and R'2 are as defined herein.

[0220] B is a difunctional or trifunctional branched unit as defined herein (determined by the properties of X1).

[0221] X2 and X3 are, independently, absent, an elastomer portion as described herein, or selected from alkyl, hydrocarbon, alkylene chain, cycloalkyl, aryl, alkylene glycol, urethane portion, and any combination thereof.

[0222] X1 is either absent, or selected from alkyl, hydrocarbon, alkylene chain, cycloalkyl, aryl, alkylene glycol, poly(alkylene glycol) moiety, urethane moiety, and elastomer moiety, each of which may optionally be substituted (e.g., terminated) with a meth(acrylate) moiety (OC(=O)CR”2=CH2), or any combination thereof, or alternatively, X1 may be represented by the following formula.

[0223] [ka]

[0224] In the equation, the curve represents the connection point. B' is a branching unit and can be the same as or different from B. X'2 and X'3 are, independently of each other, as defined herein for X2 and X3. R"2" and R"'2" are as defined herein for R2 and R'2.

[0225] However, this is subject to the condition that at least one of X1, X2, and X3 is an elastomer portion as described herein, or includes such elastomer portion.

[0226] As used herein, the term "branched unit" refers to a multi-radical, preferably an aliphatic or alicyclic group. A "multi-radical" means a structural unit having two or more bonding sites that links two or more atoms and / or groups or sites.

[0227] In other words, a branched unit is a chemical part that, when bonded to a single position, group, or atom of a substance, generates two or more functional groups linked to that single position, group, or atom, thereby "branching" a single functionality into two or more functionalities.

[0228] In some embodiments, the branched unit is derived from a chemical moiety having two, three, or more functional groups. In some embodiments, the branched unit is a branched alkyl or branched linkage moiety as defined herein.

[0229] Polyfunctional elastomer curable materials characterized by four or more polymerizable groups are also envisioned. For example, they may have a structure similar to the structure shown in Formula III, but containing a more branched unit B, or a structure containing an X1 portion having two (meth)acrylate moieties, or a structure similar to the structure shown in Formula II, but containing, for example, another (meth)acrylate moiety bonded to the elastomer portion.

[0230] In some embodiments, the elastomer portion, for example, the portion represented by Ra in formula I, or E in formulas I*, II, and III, may be linear or branched, preferably an alkyl group having three or more or four or more carbon atoms; preferably an alkylene chain having three or more or four or more carbon atoms; preferably an alkylene glycol as defined herein, an oligo(alkylene glycol) or poly(alkylene glycol) as defined herein, preferably having a length of four or more carbon atoms; preferably a urethane, oligourethane, or polyurethane as defined herein, preferably having a length of four or more carbon atoms; and any combination thereof, or comprising these.

[0231] In some of the embodiments described herein, the elastomer curable material is the (meth)acrylic curable material described herein, and in some embodiments, is acrylate or methacrylate.

[0232] In some of the embodiments described herein, the elastomer curable material is a monofunctional elastomer curable material or comprises a monofunctional elastomer curable material, and in some embodiments, the monofunctional elastomer curable material is represented by formula I, where R1 is -C(=O)-O-Ra, and Ra is urethane, oligourethane or polyurethane, or comprises urethane, oligourethane or polyurethane.

[0233] In some of the embodiments described herein, the elastomer curable material is a polyfunctional elastomer curable material or comprises a polyfunctional elastomer curable material, and in some embodiments, the polyfunctional elastomer curable material is represented by formula I*, where E is urethane, oligourethane, or polyurethane, or comprises urethane, oligourethane, or polyurethane.

[0234] In some of the embodiments described herein, the curable elastomer compound further comprises an initiator for initiating the polymerization of the curable material.

[0235] In these embodiments, if all curable materials (elastomers and additive materials) are photopolymerizable (e.g., UV curable), a photopolymerization initiator can be used.

[0236] Non-limiting examples of suitable photopolymerization initiators include benzophenones (aromatic ketones) such as benzophenone, methylbenzophenone, Michler ketone, and xanthones; acylphosphine oxide type photopolymerization initiators such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide (TMPO), 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide (TEPO), and bisacylphosphine oxides (BAPO's); and benzoin and bezoin alkyl ethers such as benzoin, benzoin methyl ether, and benzoin isopropyl ether. Examples of photopolymerization initiators include α-aminoketones and bisacylphosphine oxides (BAPO's), which are sold under the trade name "Irgacure®".

[0237] Photoinitiators can be used alone or in combination with copolymer initiators. Benzophenone is an example of a photoinitiator that requires a second molecule, such as an amine, to generate a free radical. After absorbing radiation, benzophenone undergoes a hydrogen abstraction reaction with a tertiary amine to generate an α-amino radical, thereby initiating the polymerization of acrylates. Non-limiting examples of a group of co-initiators include alkanolamines such as triethylamine, methyldiethanolamine, and triethanolamine.

[0238] According to some embodiments, the photopolymerization initiator is, for example, an "Irgacure®" type.

[0239] The concentration of the photopolymerization initiator in a formulation containing the photopolymerization initiator may be in the range of about 0.1% to about 5% by weight, or about 1% to about 3% by weight, or about 0.5% to about 2.5% by weight, or about 1% to about 2% by weight (including any intermediate and sub-ranges thereof) relative to the total weight of the formulation.

[0240] According to some of the embodiments described herein, one or more of the modeling material formulations further comprises one or more additional non-curable materials, such as colorants (dyes and / or pigments), dispersants, surfactants, stabilizers, plasticizers, antioxidants, and inhibitors.

[0241] Inhibitors are included in the formulation to prevent or delay polymerization and / or curing before exposure to curing conditions. Commonly used inhibitors include radical inhibitors.

[0242] In any of the exemplary modeling material formulations described herein, the concentration of the inhibitor is in the range of 0% by weight to about 2% by weight, or 0% by weight to about 1% by weight, relative to the total weight of the formulation or the formulation system containing it, for example, 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or about 1% by weight (including any intermediate values ​​therein).

[0243] Commonly used surfactants, dispersants, colorants, antioxidants, and stabilizers are examples. Specific concentrations of each component are in the range of approximately 0.01% to 1% by weight, or approximately 0.01% to 0.5% by weight, or approximately 0.01% to 0.1% by weight, relative to the total weight of the formulation containing that component.

[0244] Commonly used plasticizers are assumed, and preferred, are slow-evaporating plasticizers (characterized by low evaporation rates, for example, less than 1 or less than 0.5 compared to n-butyl acetate as a reference material), such as alkylene glycol alkyl ethers (e.g., dipropylene glycol mono-n-butyl ether, dipropylene glycol mono-methyl ether, and similar substances). Without being bound by any particular theory, it is presumed and demonstrated (data not shown) that such plasticizers favorably affect the Shore hardness of the cured material (i.e., reduce the Shore hardness) without adversely affecting other mechanical properties. In some embodiments, when a plasticizer is added, the Shore hardness value of the cured material decreases by 10%, 20%, 25%, or more compared to the same formulation without the plasticizer.

[0245] If present, the plasticizers described herein are present in amounts ranging from about 0.01% to about 5% by weight, or about 0.01% to about 2% by weight, or about 0.01% to about 1% by weight, or about 0.1% to about 5% by weight, or about 0.1% to about 2% by weight, or about 0.1% to about 1% by weight, or about 0.5% to about 5% by weight, or about 0.5% to about 3% by weight, or about 0.5% to about 2% by weight, or about 0.5% to about 1.5% by weight.

[0246] In any of the exemplary modeling material formulations described herein, the concentration of the surfactant is in the range of 0% to about 1% by weight relative to the total weight of the formulation or the formulation system containing it, for example, 0%, 0.01%, 0.05%, 0.1%, 0.5%, or about 1% by weight (including any intermediate values ​​therein).

[0247] In any of the exemplary modeling material formulations described herein, the concentration of the dispersant is in the range of 0% by weight to about 2% by weight relative to the total weight of the formulation or the formulation system containing it, for example, 0%, 0.1%, 0.5%, 0.7%, 1%, 1.2%, 1.3%, 1.35%, 1.4%, 1.5%, 1.7%, 1.8%, or about 2% by weight (including any intermediate values ​​therein).

[0248] <Method> According to one aspect of several embodiments of the present invention, an additive manufacturing method for a three-dimensional object is provided herein. The method of this embodiment can be used to manufacture an object having at least a portion of an elastomer material as defined herein.

[0249] This method generally involves sequentially forming multiple layers in a configuration pattern corresponding to the shape of an object, wherein at least some of the multiple layers, or each of the multiple layers, is formed from a molding material (uncured) containing one or more modeling material formulations, and the modeling material is exposed to curing conditions, preferably curing energy (e.g., irradiation), thereby forming a cured modeling material layer by layer (details will be described later).

[0250] In some exemplary embodiments of the present invention, an object is manufactured using a modeling material (uncured) comprising two or more different modeling material formulations, as described below, for example. In some of these embodiments, each modeling material formulation is ejected from different nozzle arrays belonging to the same or different ejection heads of an inkjet printer, as described herein.

[0251] In some embodiments, two or more such nozzle arrays dispensing different modeling material formulations are both located on the same print head of an additive manufacturing apparatus (i.e., a multi-channel print head). In some embodiments, the arrays of nozzles dispensing different modeling material formulations are located on separate print heads, for example, a first nozzle array dispensing a first modeling material formulation is located on a first print head, and a second nozzle array dispensing a second modeling material formulation is located on a second print head.

[0252] In some embodiments, both the nozzle array for ejecting the modeling material formulation and the nozzle array for ejecting the support material formulation are located on the same print head. In some embodiments, the nozzle array for ejecting the modeling material formulation and the nozzle array for ejecting the support material formulation are located on separate print heads.

[0253] Modeling material formulations are optionally, and preferably, deposited in layers within the same pass of the print head. The modeling material formulations and / or combinations of formulations within the layers are selected according to the desired properties of the object, and are described in further detail below. Such a mode of operation is also referred to herein as “multimaterial”.

[0254] In some embodiments of the present invention, once a layer is extruded, as described herein, exposure to curing conditions (e.g., curing energy) as described herein is carried out. In some embodiments, the curable material is a photocurable material, preferably a UV curable material, and the curing conditions are such that a radiation source emits UV radiation.

[0255] In some of the embodiments described herein, the UV irradiation is from an LED light source, as described herein.

[0256] In some of the embodiments described herein, the curing conditions include electromagnetic irradiation, and the electromagnetic irradiation is from an LED light source.

[0257] <System> A representative and non-limiting example of a system 110 suitable for additive manufacturing of an object 112, according to some embodiments of the present invention, is shown in Figure 1A. The system 110 comprises an additive manufacturing apparatus 114 having an ejection unit 16 including a plurality of print heads. Each head preferably includes one or more nozzle arrays 122, usually mounted on an orifice plate 121, as shown in Figures 2A to 2C described below, through which a liquid molding material formulation 124 is ejected.

[0258] Preferably, but not required, the apparatus 114 is a three-dimensional printing apparatus, in which case the print head is a print head and the modeling material formulation is ejected by inkjet technology. This is not necessarily required, because depending on the application, the additive manufacturing apparatus may not need to employ three-dimensional printing technology. Representative examples of additive manufacturing apparatuses envisioned according to various exemplary embodiments of the present invention include, but are not limited to, fused deposition modeling apparatuses and fused material formulation deposition apparatuses.

[0259] Each print head is optionally and preferably supplied via one or more material formulation reservoirs, which may optionally include a temperature control unit (e.g., a temperature sensor and / or a heating device) and a material formulation level sensor. To eject the material formulation, a voltage signal is applied to the print head, for example, in piezoelectric inkjet printing technology, to selectively deposit droplets of the material formulation through the print head nozzles. Another example is a thermal inkjet print head. These types of heads have a heater element that is in thermal contact with the material formulation, and when the heater element is activated by a voltage signal, the heater element heats the material formulation and forms bubbles inside it. The bubbles generate pressure in the material formulation, causing droplets of the material formulation to be ejected from the nozzles. Piezoelectric and thermal print heads are known to those skilled in the field of solid freeform fabrication. In either type of inkjet print head, the ejection speed of the head depends on the number of nozzles, the type of nozzles, and the applied voltage signal rate (frequency).

[0260] Preferably, but not required, the total number of ejection nozzles or nozzle arrays is selected such that half of the ejection nozzles are for ejecting the support material formulation and the other half are for ejecting the modeling material formulation. That is, the number of nozzles ejecting the modeling material formulation is the same as the number of nozzles ejecting the support material formulation. In a representative example in Figure 1A, four print heads 16a, 16b, 16c, and 16d are shown. Each of the heads 16a, 16b, 16c, and 16d has a nozzle array. In this example, heads 16a and 16b can be used for one or more modeling material formulations, and heads 16c and 16d can be used for support material formulations. Thus, head 16a can eject one modeling material formulation, head 16b can eject another modeling material formulation, and both heads 16c and 16d can eject support material formulations. In an alternative embodiment, for example, heads 16c and 16d can be combined to form a single head with two nozzle arrays for depositing support material formulations. In further alternative embodiments, one or more print heads may have multiple nozzle arrays for depositing multiple material formulations. For example, there may be two nozzle arrays for depositing two different modeling material formulations, or two nozzle arrays for depositing a modeling material formulation and a support material formulation, with each formulation deposited via a different array or a different number of nozzles.

[0261] However, it should be understood that the number of modeling material formulation print heads (modeling heads) and the number of support material formulation print heads (support heads) may differ, without the intention of limiting the scope of the present invention. Generally, the number of nozzle arrays for ejecting the modeling material formulation, the number of nozzle arrays for ejecting the support material formulation, and the number of nozzles in each array are selected to give a predetermined ratio a between the maximum ejection speed of the support material formulation and the maximum ejection speed of the modeling material formulation. Preferably, the value of the predetermined ratio a is selected so that in each formed layer, the height of the modeling material formulation is reliably equal to the height of the support material formulation. Typical values ​​of a are about 0.6 to about 1.5.

[0262] For example, when a=1, if all nozzle arrays are operating, the overall discharge rate of the support material formulation is approximately equal to the overall discharge rate of the modeling material formulation.

[0263] The additive manufacturing apparatus 114 may comprise, for example, M modeling heads, each having m arrays of p nozzles, and S support heads, each having s arrays of q nozzles, where M × m × p = S × s × q. Each of the M × m modeling arrays and S × s support arrays can be manufactured as a separate physical unit and can be assembled and disassembled from a group of arrays. In this embodiment, each such array optionally and preferably comprises its own temperature control unit and material composition level sensor, which receive individually controlled voltages for its operation.

[0264] The additive manufacturing apparatus 114 may further include a solidifying device 324. The solidifying device 324 may include any device configured to emit light, heat, or the like that can harden the deposited material formulation. For example, the solidifying device 324 may include one or more radiation sources. Depending on the modeling material formulation used, the radiation sources may be, for example, ultraviolet, visible light, or infrared lamps, or other electromagnetic radiation sources, or electron beam sources. In some embodiments of the present invention, the solidifying device 324 plays a role in hardening or solidifying the modeling material formulation.

[0265] In addition to the solidification apparatus 324, the additive manufacturing apparatus 114 optionally and preferably comprises an additional radiation source 328 for evaporating the solvent. The radiation source 328 optionally and preferably generates infrared radiation. In various exemplary embodiments of the present invention, the solidification apparatus 324 includes a radiation source that generates ultraviolet radiation, and the radiation source 328 generates infrared radiation.

[0266] In some embodiments of the present invention, the additive manufacturing apparatus 114 includes one or more cooling systems 134, such as fans.

[0267] The print head(s) and radiation source are preferably mounted on a frame or block 128, which is operable to reciprocate on a tray 360, which preferably serves as a work surface. In some embodiments of the present invention, the radiation source is mounted on a block and is configured to follow the print head to at least partially cure or solidify the material formulation just ejected by the print head. The tray 360 is positioned horizontally. Following common practice, an XYZ Cartesian coordinate system is selected such that the XY plane is parallel to the tray 360. The tray 360 is preferably configured to move vertically (along the Z direction), usually downward. In various exemplary embodiments of the present invention, the additive manufacturing apparatus 114 further includes one or more planaring devices 132, e.g., rollers 326. The planaring device 326 serves to straighten, planarize and / or establish the thickness of a newly formed layer before a subsequent layer is formed on it. The planarization device 326 preferably includes a waste recovery device 136 for recovering excess material mixture generated during planarization. The waste recovery device 136 may include any mechanism for delivering the material mixture to a waste tank or waste cartridge.

[0268] During use, the print head of unit 16 moves in a scanning direction referred to herein as the X direction, selectively ejecting a build material mixture in a predetermined configuration as it passes over the tray 360. The build material mixture typically includes one or more support material mixtures and one or more modeling material mixtures. Following the passage of the print head of unit 16, the one or more modeling material mixtures are cured by the radiation source 126. Additional ejection of the build material mixture may be performed according to a predetermined configuration as the head passes in the reverse direction back to the starting point of the newly deposited layer. The layer thus formed may be smoothed by a planarizer 326, which preferably follows the forward and / or reverse path of the print head as it passes forward and / or reverse. As the print head returns to the starting point along the X direction, the print head may move to another position along the index direction referred to herein as the Y direction, and continue building the same layer by reciprocating along the X direction. Alternatively, the print head may move in the Y direction between forward and reverse movements, or after multiple forward and reverse movements. A series of scans performed by the print head to complete a single layer is referred to herein as a single scan cycle.

[0269] Once a layer is complete, the tray 360 is lowered in the Z direction to a predetermined Z level, depending on the desired thickness of the next layer to be printed. This procedure is repeated, and the three-dimensional object 112 is formed layer by layer.

[0270] In another embodiment, the tray 360 may be displaced in the Z direction while the print head of unit 16 passes through the layer in the forward and reverse directions. Such displacement in the Z direction is performed so that the planarizing device contacts the surface in one direction but not in the other.

[0271] System 110 optionally and preferably includes a molding material formulation container or cartridge, and comprises a molding material formulation supply system 330 that supplies multiple molding material formulations to the additive manufacturing apparatus 114.

[0272] The control unit 152 also controls the additive manufacturing apparatus 114 and, optionally and preferably, the supply system 330. The control unit 152 typically includes electronic circuits configured to perform control operations. The control unit 152 preferably communicates with the data processor 154. The data processor 154 transmits digital data relating to manufacturing instructions based on computer object data, such as CAD configurations displayed on a computer-readable medium in a format such as Standard Tessellation Language (STL). Typically, the control unit 152 controls the voltage applied to each print head or each nozzle array, and the temperature of the molding material mixture within each print head or each nozzle array.

[0273] Once the manufacturing data is loaded into the control unit 152, the control unit 152 is operational without user intervention. In some embodiments, the control unit 152 receives additional input from the operator, for example, using a data processor 154 or a user interface 116 that communicates with the control unit 152. The user interface 116 can be any type known in the art, such as a keyboard or touchscreen, but is not limited thereto. For example, the control unit 152 may receive, but is not limited thereto, the type and / or attributes (such as color, characteristic strain and / or transition temperature, viscosity, electrical properties, magnetic properties, etc.) of one or more material formulations as additional input. Other attributes and attribute groups are also conceivable.

[0274] Other representative and non-limiting examples of system 10 suitable for additive manufacturing of objects according to some embodiments of the present invention are shown in Figures 1B to 1D. Figures 1B to 1D show a top view (Figure 1B), a side view (Figure 1C), and an isometric view (Figure 1D) of system 10.

[0275] In this embodiment, the system 10 includes a tray 12 and a plurality of inkjet print heads 16, and each inkjet print head has one or more nozzle arrays each including a plurality of separated nozzles. The material used for three-dimensional printing is supplied to the head 16 by a shaping material supply system 42. The tray 12 can have a disk-shaped or annular shape. A non-circular shape is also envisioned as long as it can rotate about a vertical axis.

[0276] The tray 12 and the head 16 are optionally and preferably attached so as to enable relative rotational movement between the tray 12 and the head 16. This can be achieved by (i) configuring the tray 12 to rotate about the vertical axis 14 relative to the head 16, (ii) configuring the head 16 to rotate about the vertical axis 14 relative to the tray 12, or (iii) configuring both the tray 12 and the head 16 to rotate about the vertical axis 14 (however, the rotational speeds are different (for example, rotation in opposite directions)). In the following, some embodiments of the system 10 will be described with particular emphasis on configuration (i) in which the tray is a rotating tray configured to rotate about the vertical axis 14 relative to the head 16, but it should be understood that this application also contemplates configurations (ii) and (iii) of the system 10. Any embodiment of the system 10 described herein can be adjusted to be applicable to either configuration (ii) or (iii), and those skilled in the art will know how to make such adjustments given the details described herein.

[0277] In the following description, the direction parallel to the tray 12 and facing outward from the axis 14 is referred to as the radial direction r, the direction parallel to the tray 12 and perpendicular to the radial direction r is referred to as the azimuthal direction φ herein, and the direction perpendicular to the tray 12 is referred to as the vertical direction z herein.

[0278] As used herein, the term "radial position" refers to a position on or above tray 12 that is at a specific distance from axis 14. When this term is used in relation to the print head, this term refers to the position of the head that is at a specific distance from axis 14. When this term is used in relation to a point on tray 12, this term corresponds to any point belonging to the locus of points that form a circle whose radius is at a specific distance from axis 14 and whose center is on axis 14.

[0279] As used herein, the term "azimuthal position" refers to a position on or above tray 12 that is at a specific azimuth with respect to a predetermined reference point. Thus, the radial position refers to any point belonging to the locus of points that form a straight line that makes a specific azimuth with respect to the reference point.

[0280] As used herein, the term "vertical position" refers to a position on a plane that intersects the vertical axis 14 at a specific point.

[0281] Tray 12 functions as a build platform for three-dimensional printing. The work area on which one or more objects are printed is usually smaller than the total area of ​​tray 12, but is not necessarily required. In some embodiments of the present invention, the work area is annular. The work area is indicated by reference numeral 26. In some embodiments of the present invention, tray 12 rotates continuously in the same direction during the formation of an object, and in some embodiments of the present invention, the tray reverses its direction of rotation at least once (e.g., in an oscillating manner) during the formation of an object. Tray 12 is optionally and preferably removable. Removal of tray 12 may be for maintenance of system 10 or, if necessary, to replace the tray before printing a new object. In some embodiments of the present invention, system 10 comprises one or more different replacement trays (e.g., a kit of replacement trays), where two or more trays are designated for different types of objects (e.g., different weights), different operating modes (e.g., different rotation speeds), etc. Replacement of tray 12 may be performed manually or automatically as desired. If automatic replacement is employed, the system 10 includes a tray changer 36 configured to remove the tray 12 from its position below the head 16 and replace it with a replacement tray (not shown). In the typical example in Figure 1B, the tray changer 36 is shown as a drive unit 38 with a movable arm 40 configured to pull the tray 12, but other types of tray changers are also conceivable.

[0282] Exemplary embodiments of the print head 16 are shown in Figures 2A to 2C. These embodiments are not limited to those described above and can be used in any of the additive manufacturing systems, including system 110 and system 10.

[0283] Figures 2A and 2B show a print head 16 with one nozzle array 22 (Figure 2A) and a print head 16 with two nozzle arrays 22 (Figure 2B). The nozzles in the arrays are preferably arranged linearly along a straight line. In embodiments in which a particular print head has two or more linear nozzle arrays, the nozzle arrays can optionally and preferably be parallel to each other. When a print head has two or more nozzle arrays (for example, Figure 2B), the same material formulation can be supplied to all arrays of the head, or different material formulations can be supplied to at least two arrays of the same head.

[0284] If a system similar to system 110 is employed, all print heads 16 are optionally and preferably oriented along the indexing direction, and their positions along the scanning direction are offset from one another.

[0285] If a system similar to system 10 is employed, all print heads 16 are optionally and preferably oriented radially (parallel to the radial direction), and their azimuth positions are offset from one another. Thus, in these embodiments, the nozzle arrays of different print heads are not parallel to each other, but rather at an angle, and this angle is approximately equal to the azimuth offset between the respective heads. For example, one head may be radially oriented and positioned at azimuth position φ1, and another head may be radially oriented and positioned at azimuth position φ2. In this example, the azimuth offset between the two heads is φ1-φ2, and the angle between the linear nozzle arrays of the two heads is also φ1-φ2.

[0286] In some embodiments, two or more print heads can be assembled into a single print head block. In this case, the print heads in the block are typically parallel to each other. A block containing multiple inkjet print heads 16a, 16b, 16c is shown in Figure 2C.

[0287] In some embodiments, the system 10 includes a stabilization structure 30 positioned below the head 16 such that the tray 12 is positioned between the stabilization structure 30 and the head 16. The stabilization structure 30 can serve to prevent or reduce vibrations of the tray 12 that may occur while the inkjet print head 16 is operating. In configurations in which the print head 16 rotates around an axis 14, the stabilization structure 30 preferably also rotates so that the stabilization structure 30 is always directly below the head 16 (with the tray 12 between the head 16 and the tray 12).

[0288] The tray 12 and / or print head 16 are optionally and preferably configured to move along a vertical direction z parallel to the vertical axis 14 in order to change the vertical distance between the tray 12 and the print head 16. In a configuration in which the vertical distance is changed by moving the tray 12 along the vertical direction, it is preferable that the stabilization structure 30 also moves vertically together with the tray 12. In a configuration in which the vertical distance is changed by moving the head 16 along the vertical direction while the vertical position of the tray 12 remains fixed, the stabilization structure 30 is also maintained in a fixed vertical position.

[0289] Vertical movement can be established by the vertical drive unit 28. Once a layer is completed, the vertical distance between the tray 12 and the head 16 can be increased by a predetermined vertical interval depending on the desired thickness of the next layer to be printed (for example, by lowering the tray 12 relative to the head 16). This procedure is repeated to form a three-dimensional object layer by layer.

[0290] The operation of the inkjet print head 16, and optionally, and preferably, the operation of one or more other components of the system 10, such as the movement of the tray 12, are controlled by the controller 20. The controller may include electronic circuits and a non-volatile storage medium readable by the circuits, which stores program instructions that, when read by the circuits, cause the circuits to perform control operations, as will be further detailed below.

[0291] The controller 20 can also communicate with a host computer 24 that transmits digital data relating to manufacturing instructions based on computer object data in any format suitable for computer-aided design (CAD), such as Standard Tessellation Language (STL) or Stereolithography Contour (SLC) format, Virtual Reality Modeling Language (VRML), Additive Manufacturing File (AMF) format, Drawing Exchange Format (DXF), Polygon File Format (PLY), 3MF (3D Manufacturing Format), Object File Format (OBJ), or any other format suitable for computer-aided design (CAD). The object data format is typically structured according to the Cartesian coordinate system. In these cases, it is preferable that the computer 24 performs a procedure to convert the coordinates of each slice in the computer object data from the Cartesian coordinate system to the polar coordinate system. The computer 24 optionally and preferably transmits the manufacturing instructions using the converted coordinate system. Alternatively, the computer 24 can transmit the manufacturing instructions using the original coordinate system provided by the computer object data, in which case the coordinate conversion is performed by the circuitry of the controller 20.

[0292] Coordinate transformation enables three-dimensional printing on a rotating tray. In a non-rotating system with a fixed tray, the print head typically moves back and forth along a straight line above the fixed tray. In such a system, if the head ejection speed is uniform, the print resolution is the same at any position on the tray. In system 10, unlike a non-rotating system, not all nozzles at the head point move the same distance on the tray 12 in the same amount of time. Coordinate transformation is optionally and preferably performed so that the excess material composition is equal at different radial positions. Representative examples of coordinate transformations according to some embodiments of the present invention are provided in Figures 3A and 3B, showing three slices of an object (each slice corresponding to a manufacturing instruction for a different layer of the object), where Figure 3A shows the slices in Cartesian coordinates, and Figure 3B shows the same slices after applying the coordinate transformation procedure to each slice.

[0293] Typically, the controller 20 controls the voltage applied to each component of the system 10 based on manufacturing instructions and stored program instructions, as described below.

[0294] Generally, the controller 20 controls the print head 16 while the tray 12 is rotating to eject droplets of the molding material mixture in layers, for example, to print a three-dimensional object on the tray 12.

[0295] System 10 optionally and preferably comprises one or more radiation sources 18. Depending on the modeling material formulation used, the radiation sources 18 may be, for example, ultraviolet, visible light, or infrared lamps, or other electromagnetic radiation sources, or electron beam sources. Examples of radiation sources include, but are not limited to, any type of radiation emitter, including light-emitting diodes (LEDs), digital light processing (DLP) systems, and resistor lamps. The radiation sources 18 play a role in curing or solidifying the modeling material formulation. In various exemplary embodiments of the present invention, the operation of the radiation sources 18 is controlled by a controller 20, which may activate and deactivate the radiation sources 18, and may also optionally control the amount of radiation emitted by the radiation sources 18.

[0296] In some embodiments of the present invention, the system 10 further includes one or more planaring devices 32, which may be manufactured as rollers 326 or blades. The planaring devices 32 serve to prepare the newly formed layer before forming the next layer. In some embodiments, the planaring device 32 has the shape of a conical roller, with its axis of symmetry 34 inclined with respect to the surface of the tray 12 and its surface positioned parallel to the surface of the tray. This embodiment is shown in a side view of the system 10 (Figure 1C).

[0297] A conical roller may have the shape of a cone or a frustocone.

[0298] The opening angle of the conical roller is preferably selected such that the ratio between the radius of the cone at any position along the axis 34 of the cone and the distance between that position and the axis 14 is constant. In this embodiment, the roller 32 can efficiently flatten the layer. This is because, while the roller is rotating, the linear velocity at any point p on the surface of the roller is proportional to (e.g., the same as) the linear velocity of the tray at a point directly below point p. In some embodiments, the roller has a frustoconical shape with height h, radius R1 at the closest distance from the axis 14, and radius R2 at the furthest distance from the axis 14, where the parameters h, R1, and R2 satisfy the relationship R1 / R2=(Rh) / h, and R is the furthest distance of the roller from the axis 14 (e.g., R can be the radius of the tray 12).

[0299] The operation of the flattening device 32 is optionally and preferably controlled by a controller 20, which may activate and deactivate the flattening device 32, and optionally control the position of the flattening device 32 along the vertical direction (parallel to the axis 14) and / or the radial direction (parallel to the tray 12, moving towards or away from the axis 14).

[0300] In some embodiments of the present invention, the print head 16 is configured to reciprocate relative to the tray along a radial direction r. These embodiments are useful when the length of the nozzle array 22 of the head 16 is shorter than the radial width of the work area 26 on the tray 12. The radial movement of the head 16 is optionally, and preferably, controlled by a controller 20.

[0301] In some embodiments, it is contemplated to manufacture an object by ejecting different material formulations from different nozzle arrays (belonging to the same or different print heads). These embodiments, in particular, provide the ability to select material formulations from a given number of material formulations and to define the desired combinations of the selected material formulations and their properties. According to the present embodiment, the spatial position of the deposition of each material formulation within a layer is defined such that different material formulations occupy different three-dimensional spatial positions, or two or more different material formulations are defined to occupy substantially the same three-dimensional position or adjacent three-dimensional positions, thereby enabling the material formulations to be spatially combined after deposition within the layer, resulting in the formation of composite material formulations at each position or multiple positions.

[0302] Any combination or mixing after deposition of the modeling material formulations is contemplated. For example, when a particular material formulation is ejected, the original properties of the material may be retained. However, when a particular material formulation is ejected simultaneously with another modeling material formulation, or simultaneously with other material formulations ejected at the same or nearby positions, a composite material formulation having properties different from those of the ejected material formulation may be formed.

[0303] In some embodiments of the present invention, the system ejects digital material formulations for at least one of a plurality of layers.

[0304] As used herein and in the art, the term "digital material formulation" refers to a state in which two or more material formulations are combined at the pixel level or voxel level, and the pixels or voxels of different material formulations are interlaced with each other over a region. Such digital material formulations may exhibit new properties that are affected by the selection of the type of material formulation and / or the ratio and relative spatial distribution of two or more material formulations.

[0305] As used herein, a "voxel" refers to the basic three-dimensional physical volume within a layer, corresponding to a single pixel of the bitmap describing that layer. The size of a voxel is approximately equal to the size of the area formed by the material after it is extruded, flattened, and solidified at the location corresponding to each pixel.

[0306] Therefore, this embodiment enables the deposition of a wide range of material formulations and allows for the manufacture of an object in which different parts of the object may be composed of a combination of multiple different material formulations, depending on the desired properties for characterizing each part of the object.

[0307] Further details regarding the principles and operation of an additive manufacturing system suitable for this embodiment are described in U.S. Patent No. 9,031,680 and International Publication No. 2016 / 009426, which are incorporated herein by reference.

[0308] While this specification focuses on 3D inkjet printing, it should be noted that the curable formulations and additive manufacturing processes described herein can also be used in 3D printing methods in which the curable formulation is held in a vat, also known as VAT polymerization, and typically include stereolithography (SLA) and digital light processing (DLP) methods.

[0309] SLA and DLP are additive manufacturing techniques that convert uncured material in a casing into cured material layer by layer through selective curing using a light source, and then separate / clean the uncured material from the cured material. SLA is widely used in various industries, including bioprinting, to create models, prototypes, patterns, and production parts. DLP differs from laser-based SLA in that it uses ultraviolet (UV) light (or visible light) projection from a digital projector to flash a single image of the layer across the entire uncured material at once. One of the main components of DLP is a digital micromirror device (DMD) chip, which typically consists of an array of reflective aluminum micromirrors that reflect incident light from a UV light source to project an image of the designed pattern. To achieve high-resolution structures, it is necessary to adjust parameters such as the curing time of each layer, layer thickness, and UV light intensity, for example, by controlling the concentration and type of curable material and photoinitiator.

[0310] As used herein, the term "approximately" refers to ±10% or ±5%.

[0311] The terms "comprises," "comprising," "includes," "including," and "having," as well as their conjugations, are used to mean "to include, but not limited to."

[0312] The term "consisting of" means "including and limited to."

[0313] The term "consisting essentially of" means that a composition, method, or structure may include additional components, processes, and / or parts, but such additional components, processes, and / or parts do not substantially alter the basic and novel features of the claimed composition, method, or structure.

[0314] As used herein, the singular forms "a," "an," and "the" include plural references unless the context explicitly indicates otherwise. For example, the terms "a compound" or "at least one compound" may include multiple compounds, including mixtures thereof.

[0315] Throughout this application, various embodiments of the present invention may be presented in range form. It should be understood that range form descriptions are for convenience and simplification only and should not be interpreted as a fixed and immutable limitation to the scope of the present invention. Therefore, range descriptions should be considered to specifically disclose not only the individual numerical values ​​within that range, but also all possible sub-ranges. For example, a range description such as 1-6 should be considered to specifically disclose not only the individual numerical values ​​within that range, e.g., 1, 2, 3, 4, 5, and 6, but also sub-ranges such as 1-3, 1-4, 1-5, 2-4, 2-6, and 3-6. This applies regardless of the breadth of the range.

[0316] Wherever a numerical range is indicated herein, it is intended to include any cited number (decimal or integer) within that range. The phrases "ranging / ranges between" and "to" and "ranging / ranges from" are used interchangeably herein and mean including the first and second specified numbers, as well as all decimals and integers between them.

[0317] As used herein, the term “method” is also interchangeably referred to herein as “process,” and refers to a method, means, technique, and procedure for accomplishing a particular task. This includes, but is not limited to, methods, means, techniques, and procedures that are known to those skilled in the art of chemistry, engineering, physics, and mechanical engineering, or that can be readily developed from known methods, means, techniques, and procedures.

[0318] Throughout this specification, whenever the terms “weight percent,” “weight %,” or “%wt” appear in the context of embodiments of a formulation (e.g., a modeling formulation), they mean a weight percentage of the total weight of the respective uncured formulation.

[0319] Throughout this specification, the term "acrylic material" is used to refer collectively to materials characterized by one or more acrylate groups, methacrylate groups, acrylamide groups, and / or methacrylamide groups.

[0320] Similarly, the term "acrylic group" is used to refer collectively to curable groups that are one or more acrylate groups, methacrylate groups, acrylamide groups and / or methacrylamide groups, preferably acrylate groups or methacrylate groups (also referred to herein as (meth)acrylate groups).

[0321] Throughout this specification, the term "(meth)acrylic" encompasses both acrylic and methacrylic materials.

[0322] Throughout this specification, the terms “linking moiety” or “linking group” refer to a group that links two or more moies or groups in a compound. A linking moiety can typically be considered a bi-radical or tri-radical moiety derived from a difunctional or trifunctional compound, each linked to two or three other sites via two or three atoms.

[0323] Exemplary linking portions include, as defined herein, hydrocarbon portions or hydrocarbon chains interrupted by one or more heteroatoms of any choice, and / or, when defined as linking groups, any of the following chemical groups:

[0324] In this specification, when a chemical group is referred to as a “terminal group,” it is interpreted as a substituent that is bonded to another group via one atom of that chemical group.

[0325] Throughout this specification, the term "hydrocarbon" refers collectively to chemical groups consisting primarily of carbon atoms and hydrogen atoms. Hydrocarbons are composed of alkyl, alkene, alkyne, aryl, and / or cycloalkyl groups, each of which may be substituted or unsubstituted and may be interrupted by one or more heteroatoms. The number of carbon atoms can range from 2 to 30, preferably fewer, for example, 1 to 10, or 1 to 6, or 1 to 4. Hydrocarbons may be linking groups or terminal groups.

[0326] Bisphenol A is an example of a hydrocarbon consisting of two aryl groups and one alkyl group. Dimethylenecyclohexane is an example of a hydrocarbon consisting of two alkyl groups and one cycloalkyl group.

[0327] As used herein, the term "amine" refers to both the -NR'R” group and the -NR'- group, where R' and R” are independently hydrogen, alkyl, cycloalkyl, and aryl, respectively, and these terms are defined below.

[0328] Therefore, the amine group may be a primary amine where both R' and R'' are hydrogen, a secondary amine where R' is hydrogen and R'' is alkyl, cycloalkyl, or aryl, or a tertiary amine where R' and R'' are each independently alkyl, cycloalkyl, or aryl.

[0329] Alternatively, R' and R'' may independently be hydroxyalkyl, trihaloalkyl, cycloalkyl, alkenyl, alkynyl, aryl, heteroaryl, heteroalicyclic, amine, halogen compound, sulfonate, sulfoxide, phosphonate, hydroxy, alkoxy, aryloxy, thiohydroxy, thioalkoxy, thioaryloxy, cyano, nitro, azo, sulfonamide, carbonyl, C-carboxylate, O-carboxylate, N-thiocarbamate, O-thiocarbamate, urea, thiourea, N-carbamate, O-carbamate, C-amide, N-amide, guanyl, guanidine, and hydrazine.

[0330] In this specification, the term "amine" is used to represent the -NR'R” group when the amine is a terminal group as defined below, and in this specification, the term "-NR'-" is used to represent the -NR'- group when the amine is a linking group or part of a linking moiety.

[0331] The term "alkyl" refers to saturated aliphatic hydrocarbons containing linear and branched groups. Preferably, alkyl groups have 1 to 30 or 1 to 20 carbon atoms. Wherever a numerical range (e.g., "1 to 20") is given herein, it means that the group (in this case, the alkyl group) may contain up to 20 carbon atoms, such as 1 carbon atom, 2 carbon atoms, 3 carbon atoms, and so on. Alkyl groups may be substituted or unsubstituted. The substituted alkyl may have one or more substituents, each substituent independently of, for example, a hydroxyalkyl, trihaloalkyl, cycloalkyl, alkenyl, alkynyl, aryl, heteroaryl, alicyclic heterocycle, amine, halogen compound, sulfonate, sulfoxide, phosphonate, hydroxy, alkoxy, aryloxy, thiohydroxy, thioalkoxy, thioaryloxy, cyano, nitro, azo, sulfonamide, C-carboxylate, O-carboxylate, N-thiocarbamate, O-thiocarbamate, urea, thiourea, N-carbamate, O-carbamate, C-amide, N-amide, guanyl, guanidine, or hydrazine.

[0332] An alkyl group can be a terminal group bonded to a single adjacent atom, as defined herein, or a linking group that links two or more sites in its chain via at least two carbon atoms, as defined herein. When an alkyl group is a linking group, it is also referred herein to as an "alkylene" or "alkylene chain."

[0333] Alkenes and alkynes as used herein are alkyl groups containing one or more double or triple bonds, as defined herein.

[0334] The term "cycloalkyl" refers to an all-carbon monocyclic or fused cyclic group (i.e., a ring sharing pairs of adjacent carbon atoms) that does not have a fully conjugated π-electron system of one or more rings. Examples, though not limited to these, include cyclohexane, adamantine, norbornyl, and isobornyl. Cycloalkyl groups may be substituted or unsubstituted. A substituted cycloalkyl group may have one or more substituents, each substituent independently of, for example, a hydroxyalkyl group, a trihaloalkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, an aryl group, a heteroaryl group, an alicyclic heterocyclic group, an amine group, a halogen compound, a sulfonate group, a sulfoxide group, a phosphonate group, a hydroxy group, an alkoxy group, an aryloxy group, a thiohydroxy group, a thioalkoxy group, a thioaryloxy group, a cyano group, a nitro group, azo group, a sulfonamide group, a C-carboxylate group, an O-carboxylate group, an N-thiocarbamate group, an O-thiocarbamate group, a urea group, a thiourea group, an N-carbamate group, an O-carbamate group, a C-amide group, an N-amide group, a guanyl group, a guanidine group, and a hydrazine group. A cycloalkyl group may be a terminal group bonded to a single adjacent atom as defined herein, or a linking group in which two or more parts are linked at two or more positions as defined herein.

[0335] The term "heteroalicyclic" refers to a monocyclic or fused cyclic group that contains one or more atoms such as nitrogen, oxygen, or sulfur within the ring. The ring may have one or more double bonds. However, the ring does not have a fully conjugated π-electron system. Representative examples include piperidine, piperazine, tetrahydrofuran, tetrahydropyran, morpholino, and oxalidine.

[0336] Alicyclic heterocycles may be substituted or unsubstituted. Alicyclic heterocycles may have one or more substituents, each substituent independently of, for example, hydroxyalkyl, trihaloalkyl, cycloalkyl, alkenyl, alkynyl, aryl, heteroaryl, alicyclic heterocycle, amine, halogen compound, sulfonate, sulfoxide, phosphonate, hydroxy, alkoxy, aryloxy, thiohydroxy, thioalkoxy, thioaryloxy, cyano, nitro, azo, sulfonamide, C-carboxylate, O-carboxylate, N-thiocarbamate, O-thiocarbamate, urea, thiourea, O-carbamate, N-carbamate, C-amide, N-amide, guanyl, guanidine, and hydrazine. Alicyclic heterocycles may be terminal groups bonded to a single adjacent atom as defined herein, or linking groups connecting two or more parts at two or more positions as defined herein.

[0337] The term "aryl" refers to an all-carbon monocyclic or fused cyclic group (i.e., a ring sharing pairs of adjacent carbon atoms) having a fully conjugated π-electron system. The aryl group may be substituted or unsubstituted. A substituted aryl may have one or more substituents, each independently of which may be, for example, a hydroxyalkyl, trihaloalkyl, cycloalkyl, alkenyl, alkynyl, aryl, heteroaryl, alicyclic heterocycle, amine, halogen compound, sulfonate, sulfoxide, phosphonate, hydroxy, alkoxy, aryloxy, thiohydroxy, thioalkoxy, thioaryloxy, cyano, nitro, azo, sulfonamide, C-carboxylate, O-carboxylate, N-thiocarbamate, O-thiocarbamate, urea, thiourea, N-carbamate, O-carbamate, C-amide, N-amide, guanyl, guanidine, and hydrazine. An aryl group may be a terminal group bonded to an adjacent single atom, as defined herein, or a linking group in which two or more parts are linked at two or more positions, as defined herein.

[0338] The term "heteroaryl" refers to a monocyclic or fused cyclic group (i.e., a ring sharing one pair of adjacent atoms) that has one or more atoms, such as nitrogen, oxygen, or sulfur, within its ring, and further possesses a completely conjugated π-electron system. Examples of heteroaryl groups, though not limited to them, include pyrrole, furan, thiophene, imidazole, oxazole, thiazole, pyrazole, pyridine, pyrimidine, quinoline, isoquinoline, and purine. Heteroaryl groups may be substituted or unsubstituted. Substitutive heteroaryls may have one or more substituents, each substituent independently of, for example, hydroxyalkyl, trihaloalkyl, cycloalkyl, alkenyl, alkynyl, aryl, heteroaryl, alicyclic heterocycle, amine, halogen compound, sulfonate, sulfoxide, phosphonate, hydroxy, alkoxy, aryloxy, thiohydroxy, thioalkoxy, thioaryloxy, cyano, nitro, azo, sulfonamide, C-carboxylate, O-carboxylate, N-thiocarbamate, O-thiocarbamate, urea, thiourea, O-carbamate, N-carbamate, C-amide, N-amide, guanyl, guanidine, and hydrazine. A heteroaryl group may be a terminal group bonded to a single adjacent atom as defined herein, or a linking group connecting two or more parts at two or more positions as defined herein. Representative examples include pyridine, pyrrole, oxazole, indole, and purine.

[0339] The terms "halide" and "halo" refer to fluorine, chlorine, bromine, and iodine.

[0340] The term "haloalkyl" refers to an alkyl group as defined herein that has been further substituted with one or more halides.

[0341] The term "sulfate" refers to an -OS(=O)2-OR' terminal group or an -OS(=O)2-O-linking group, as defined herein, where R' is as defined herein.

[0342] The term "thiosulfate" refers to an -OS(=S)(=O)-OR' terminal group or an -OS(=S)(=O)-O-linking group, as defined herein, where R' is as defined herein.

[0343] The term "sulfite" refers to an -OS(=O)-O-R' terminal group or an -OS(=O)-O-linking group, as defined herein, where R' is as defined herein.

[0344] The term "thiosulfite" refers to an -OS(=S)-O-R' terminal group or -OS(=S)-O- linking group, as defined herein, where R' is as defined herein.

[0345] The term "sulfinate" refers to a -S(=O)-OR' terminal group or an -S(=O)-O-linking group, as defined herein, and R' is as defined herein.

[0346] The terms "sulfoxide" or "sulfinyl" represent an -S(=O)R' terminal group or an -S(=O)- linking group, as defined herein, where R' is as defined herein.

[0347] The term "sulfonate" refers to an -S(=O)2-R' terminal group or -S(=O)2-linking group, as defined herein, where R' is as defined herein.

[0348] The term "S-sulfonamide" refers to a -S(=O)2-NR'R” terminal group or -S(=O)2-NR'- linking group, as defined herein, where R' and R'' are as defined herein.

[0349] The term "N-sulfonamide" represents an R'S(=O)2-NR''-terminal group or an -S(=O)2-NR'-linking group, as defined herein, where R' and R'' are as defined herein.

[0350] The term "disulfide" refers to an -S-SR' terminal group or an -SS- linking group, as defined herein, where R' is as defined herein.

[0351] The term "phosphonate" refers to a -P(=O)(OR')(OR) terminal group or a -P(=O)(OR')(O)- linking group, as defined herein, where R' and R'' are as defined herein.

[0352] The term "thiophosphonate" refers to a -P(=S)(OR')(OR) terminal group or a -P(=S)(OR')(O)- linking group, as defined herein, where R' and R'' are as defined herein.

[0353] The term "phosphinyl" refers to a -PR'R" terminal group or -PR'- linking group, as defined herein, where R' and R'' are as defined herein.

[0354] The term "phosphine oxide" refers to a -P(=O)(R')(R) terminal group or -P(=O)(R')- linking group, as defined herein, where R' and R'' are as defined herein.

[0355] The term "phosphine sulfide" refers to a -P(=S)(R')(R) terminal group or -P(=S)(R')- linking group, as defined herein, where R' and R'' are as defined herein.

[0356] The term "phosphite" refers to a -O-PR'(=O)(OR) terminal group or an -O-PH(=O)(O)- linking group, as defined herein, where R' and R'' are as defined herein.

[0357] As used herein, the terms "carbonyl" or "carbonate" refer to a -C(=O)-R' terminal group or -C(=O)- linking group, as defined herein, where R' is as defined herein.

[0358] As used herein, the term "thiocarbonyl" refers to a -C(=S)-R' terminal group or -C(=S)-linking group, as defined herein, where R' is as defined herein.

[0359] As used herein, the term "oxo" refers to an (=O) group, where the oxygen atom is double-bonded to the atom at the indicated position (e.g., a carbon atom).

[0360] As used herein, the term "thiooxo" refers to a (=S) group, where a sulfur atom is double-bonded to the atom at the indicated position (e.g., a carbon atom).

[0361] The term "oxime" as defined herein refers to an N-OH terminal group or an NO-linking group.

[0362] The term "hydroxyl" represents the -OH group.

[0363] The term "alkoxy" refers to both -O-alkyl groups and -O-cycloalkyl groups, as defined herein. The term "alkoxide" refers to -R'O - It represents the base, and R' is as defined herein.

[0364] The term "aryloxy" refers to both -O-aryl groups and -O-heteroaryl groups, as defined herein.

[0365] The terms "thiohydroxy" or "thiol" refer to the -SH group. The term "thiolate" refers to the -S group. - It represents the basis.

[0366] The term "thioalkoxy" refers to both -S-alkyl groups and -S-cycloalkyl groups, as defined herein.

[0367] The term "thioaryloxy" refers to both the -S-aryl group and the -S-heteroaryl group, as defined herein.

[0368] The term "hydroxyalkyl (hydroxyalkyl)" is also referred to herein as "alcohol" and refers to an alkyl group as defined herein that is substituted with a hydroxyl group.

[0369] The term "cyano" represents the -C≡N group.

[0370] The term "isocyanate" refers to the -N=C=O group.

[0371] The term "isothiocyanate" refers to the -N=C=S group.

[0372] The term "nitro" refers to the -NO2 group.

[0373] The term "acyl halide" refers to the -(C=O)R'' group, where R'' is a halide as defined herein.

[0374] The terms "azo" or "diazo" represent an -N=NR' terminal group or -N=N- linking group, as defined herein, where R' is as defined herein.

[0375] The term "peroxo" represents an -O-OR' terminal group or an -OO- linking group, as defined herein, and R' is as defined herein.

[0376] As used herein, the term "carboxylate" encompasses both C-carboxylates and O-carboxylates.

[0377] The term "C-carboxylate" refers to a -C(=O)-OR' terminal group or -C(=O)-O-linking group, as defined herein, and R' is as defined herein.

[0378] The term "O-carboxylate" refers to an -OC(=O)R' terminal group or -OC(=O)- linking group, as defined herein, where R' is as defined herein.

[0379] Carboxylates can be linear or cyclic. In the cyclic form, R' and a carbon atom bond to form a C-carboxylate ring, also known as a lactone. Alternatively, R' and O bond to form an O-carboxylate ring. Cyclic carboxylates can function as linking groups, for example, when atoms in the formed ring bond to another group.

[0380] As used herein, the term "thiocarboxylate" encompasses both C-thiocarboxylate and O-thiocarboxylate.

[0381] The term "C-thiocarboxylate" represents a -C(=S)-OR' terminal group or -C(=S)-O-linking group, as defined herein, and R' is as defined herein.

[0382] The term "0-thiocarboxylate" refers to an -OC(=S)R' terminal group or -OC(=S)- linking group, as defined herein, where R' is as defined herein.

[0383] Thiocarboxylates can be linear or cyclic. In the cyclic form, R' bonds with a carbon atom to form a C-thiocarboxylate ring, also known as a thiolactone. Alternatively, R' bonds with O to form an O-thiocarboxylate ring. Cyclic thiocarboxylates can function as linking groups, for example, when atoms in the formed ring bond with another group.

[0384] As used herein, the term "carbamate" includes both N-carbamates and O-carbamates.

[0385] The term "N-carbamate" refers to an R''OC(=O)-NR'-terminal group or -OC(=O)-NR'-linking group, as defined herein, where R' and R'' are as defined herein.

[0386] The term "O-carbamate" refers to the -OC(=O)-NR'R” terminal group or -OC(=O)-NR'- linking group, as defined herein, where R' and R'' are as defined herein.

[0387] Carbamates can be linear or cyclic. In the cyclic form, R' bonds with carbon atoms to form an O-carbamate ring, or R' bonds with O to form an N-carbamate ring. Cyclic carbamates can function as linking groups, for example, when atoms in the formed ring bond with another group.

[0388] As used herein, the term "carbamate" includes both N-carbamates and O-carbamates.

[0389] As used herein, the term "thiocarbamate" encompasses both N-thiocarbamates and O-thiocarbamates.

[0390] The term "O-thiocarbamate" refers to the -OC(=S)-NR'R” terminal group or -OC(=S)-NR'- linking group, as defined herein, where R' and R'' are as defined herein.

[0391] The term "N-thiocarbamate" represents an R''OC(=S)NR'-terminal group or -OC(=S)NR'-linking group, as defined herein, where R' and R'' are as defined herein.

[0392] Thiocarbamates may be linear or cyclic, as described herein for carbamates.

[0393] As used herein, the term "dithiocarbamate" encompasses both S-dithiocarbamates and N-dithiocarbamates.

[0394] The term "S-dithiocarbamate" refers to the -SC(=S)-NR'R” terminal group or -SC(=S)NR'- linking group, as defined herein, where R' and R'' are as defined herein.

[0395] The term "N-dithiocarbamate" represents an R''SC(=S)NR'-terminal group or -SC(=S)NR'-linking group, as defined herein, where R' and R'' are as defined herein.

[0396] The term "urea" is also referred to herein as "ureido," and represents a -NR'C(=O)-NR"R"' terminal group or -NR'C(=O)-NR"- linking group as defined herein, where R' and R" are as defined herein, and R"' is as defined herein with respect to R' and R".

[0397] The term "thiourea" is also referred to herein as "thioureido," and represents a -NR'-C(=S)-NR"R"' terminal group or an -NR'-C(=S)-NR"- linking group, where R', R" and R"' are as defined herein.

[0398] As used herein, the term "amide" encompasses both C-amides and N-amides.

[0399] The term "C-amide" represents a -C(=O)-NR'R” terminal group or -C(=O)-NR'- linking group, as defined herein, where R' and R'' are as defined herein.

[0400] The term "N-amide" refers to an R'C(=O)-NR”-terminal group or R'C(=O)-N-linking group, as defined herein, where R' and R” are as defined herein.

[0401] Amides can be linear or cyclic. In the cyclic form, R' bonds with a carbon atom to form a ring, resulting in a C-amide, also known as a lactam. Cyclic amides can function as linking groups, for example, when atoms in the formed ring bond with another group.

[0402] The term "guanyl" represents an R'R”NC(=N)-terminal group or an -R'NC(=N)-linking group, as defined herein, where R' and R” are as defined herein.

[0403] The term "guanidine" represents the -R'NC(=N)-NR"R"' terminal group or -R'NC(=N)-NR"- linking group as defined herein, where R', R" and R"' are as defined herein.

[0404] The term "hydrazine" refers to a -NR'-NR”R”' terminal group or -NR'-NR”- linking group, as defined herein, where R', R” and R”' are as defined herein.

[0405] As used herein, the term "hydrazide" refers to a -C(=O)-NR'-NR”R”' terminal group or a -C(=O)-NR'-NR”- linking group, as defined herein, where R', R” and R”' are as defined herein.

[0406] As used herein, the term "thiohydrazide" refers to a -C(=S)-NR'-NR”R”' terminal group or a -C(=S)-NR'-NR”- linking group, as defined herein, where R', R” and R”' are as defined herein.

[0407] The term "cyanurate" is,

[0408] [ka]

[0409] terminal group or

[0410] [ka]

[0411] These represent linking groups, where R' and R'' are as defined herein.

[0412] The term "isocyanurate" is,

[0413] [ka]

[0414] terminal group or

[0415] [ka]

[0416] These represent linking groups, where R' and R'' are as defined herein.

[0417] The term "thiocyanurate" is,

[0418] [ka]

[0419] terminal group or

[0420] [ka]

[0421] These represent linking groups, where R' and R'' are as defined herein.

[0422] The term "alkylene glycol" as used herein refers to -O-[(CR'R)] z -O] y -R” terminal group or -O-[(CR'R)”) z -O] y - Represents a linking group, where R', R' and R'' are as defined herein, z is an integer from 1 to 10, preferably 2 to 6, more preferably 2 or 3, and y is an integer of 1 or more. Preferably, both R' and R'' are hydrogen. When z=2 and y=1, this group is ethylene glycol. When z=3 and y=1, this group is propylene glycol. When y=2 to 4, this alkylene glycol is referred to herein as oligo(alkylene glycol).

[0423] Here, "ethoxylated" material refers to an acrylic or methacrylic compound containing one or more alkylene glycol groups, or preferably one or more alkylene glycol chains, as defined herein. The ethoxylated (meth)acrylate material may be monofunctional, or preferably polyfunctional, i.e., difunctional, trifunctional, tetrafunctional, etc.

[0424] In polyfunctional materials, each (meth)acrylate group is typically bonded to an alkylene glycol group or alkylene glycol chain, and these alkylene glycol groups or chains are bonded to each other via branched units such as branched alkyl, cycloalkyl, or aryl (e.g., bisphenol A).

[0425] In some embodiments, the ethoxylated material comprises at least one or at least two ethoxylated groups, i.e., at least one or at least two alkylene glycol moieties or groups. Some or all of the alkylene glycol groups can bond to each other to form an alkylene glycol chain. For example, an ethoxylated material containing 30 ethoxylated groups may include one chain of 30 alkylene glycol groups bonded to each other, for example, two chains of 15 alkylene glycol moieties each bonded to each other (these two chains are bonded to each other via branching), or for example, three chains of 10 alkylene glycol groups each bonded to each other (these three chains are bonded to each other via branching). Shorter and longer chains are also envisioned.

[0426] The ethoxylated material may contain one, two, or more alkylene glycol chains of any length.

[0427] As used herein, the term "branched unit" refers to a multi-radical, preferably an aliphatic or alicyclic group. A "multi-radical" means a structural unit having two or more bonding sites that links two or more atoms and / or groups or sites.

[0428] In some embodiments, the branched unit is derived from a chemical moiety having two, three, or more functional groups. In some embodiments, the branched unit is a branched alkyl, cycloalkyl (alicyclic), or aryl (e.g., phenyl) as defined herein.

[0429] Throughout this specification, unless otherwise specified, viscosity values ​​are given as the viscosity of the material or compound measured with a Brookfield viscometer at 25°C. The measurements are given in centipoise units, which correspond to mPa·seconds.

[0430] Throughout this specification, "Tg" refers to the glass transition temperature of a material, which is defined as the location of the local maximum on the curve of the loss factor E'' with respect to temperature.

[0431] Roughly speaking, as the temperature rises within the temperature range that includes Tg, the state of a material, especially a polymer material, gradually changes from a glassy state to a rubbery state.

[0432] Here, the "Tg range" refers to the temperature range in which the E'' value is at least half of the E'' value at the Tg temperature defined above (for example, it may reach that value).

[0433] While we do not wish to be bound by any particular theory, it is presumed that the state of polymer materials gradually changes from glassy to rubbery within the Tg range defined herein. In this specification, the lowest temperature in the Tg range is referred to as Tg(low), and the highest temperature in the Tg range is referred to as Tg(high).

[0434] Throughout this specification, whenever a curable material is defined by the properties of the cured material obtained from it, those properties should be understood as properties of the cured material obtained from the curable material itself.

[0435] Throughout this specification, where the terms “weight percent,” “weight %,” or “%wt” appear in the context of embodiments of a formulation (e.g., a modeling formulation), they mean a weight percentage of the total weight of the corresponding uncured formulation.

[0436] While certain features of the present invention are described in the context of separate embodiments for clarity, it should be understood that these features can also be provided in combination in a single embodiment. Conversely, various features of the present invention described in the context of a single embodiment for brevity may be provided separately, in any suitable subcombination, or in any other described embodiment of the present invention. Certain features described in the context of various embodiments are not considered essential features of those embodiments unless the embodiment would not function without those elements.

[0437] The various embodiments and aspects of the present invention described above and claimed in the following claims are experimentally supported in the following examples. [Examples]

[0438] The following examples are provided below to illustrate, in conjunction with the above description, some embodiments of the present invention in a non-limiting manner.

[0439] <Experimental Method> Shore A hardness was measured according to ASTM D2240.

[0440] Tensile strength is measured according to ASTM D412 and expressed in MPa units.

[0441] Elongation at break is measured according to ASTM D412 and expressed as a percentage.

[0442] Tear resistance (TR) is measured according to ASTM D624 and expressed in kg / cm units.

[0443] Resilience (energy dissipation efficiency; EDE) was determined based on a periodic strain-strain curve using the following formula, as described in Zhao et al., Molecules 2020, 25, 597.

[0444]

number

[0445] Viscosity is measured using a Brookfield viscometer and expressed as Brookfield viscosity in centipoise units, which corresponds to mPa / second.

[0446] Surface tension is measured using a Kruss K6 Force Tensiometer and expressed in units of Dyne / cm.

[0447] Unless otherwise specified, all components of the formulations were prepared by mixing them at room temperature. Powdered components such as photopolymerization initiators were dissolved at 85°C for 30 minutes.

[0448] (Example 1) -design- The inventors have found that formulations currently available and / or in practical use for additive manufacturing (e.g., 3D inkjet printing), which provide an elastomer material upon curing, exhibit desirable flexibility, but the resilience of the cured material is not ideal. Therefore, the cured material does not return to its original shape within a reasonable time after temporary bending (i.e., the recovery rate is not sufficiently high). This unideal resilience limits the use of these materials in certain applications (e.g., forming three-dimensional objects on fabric).

[0449] Therefore, the inventors sought solutions to the relatively low resilience of currently available formulations and investigated the effects of various silicone-containing polymer materials on the resilience and other properties of curable elastomer formulations.

[0450] The inventors tested the effects of adding various silicone-containing polymer materials in various amounts to various elastomer formulations and found the type and / or amount of silicone-containing polymer material that achieves the desired improvement in resilience while maintaining other mechanical properties of the formulation at acceptable levels.

[0451] The tested silicone-containing polymer materials included reactive materials having one or more curable groups. These reactive materials can be divided into monofunctional curable silicone-containing polymer materials and polyfunctional curable silicone-containing polymer materials. Non-reactive materials that did not contain curable groups were also included.

[0452] Table 1 shows examples of reactive and non-reactive silicone-containing polymer materials.

[0453] Silicones refer to polymeric or oligomeric siloxanes (polysiloxanes), typically polydimethylsiloxane (PDMS), or other unsubstituted polysiloxanes, or polysiloxanes substituted with other alkyl, cycloalkyl, and / or aryl groups.

[0454] Silicone polyethers typically refer to siloxanes of the polymers or oligomers described herein, which are substituted at one or both ends with a polyether such as PEG.

[0455] Silicone polyester typically refers to a siloxane of the polymer or oligomer described herein, bonded to a polyester at one or more positions. The silicone portion may have one or more curable groups.

[0456] Silicone acrylate / methacrylate / urethane acrylate typically refers to siloxanes of polymers or oligomers described herein, in which one or both of their ends are substituted with the corresponding curable acrylate group or urethane acrylate group.

[0457] "Functionality" refers to the number of curable groups per molecule.

[0458] Molecular weight is expressed in grams per mole (g / mol).

[0459] "Suitability" refers to factors such as toxicity and compatibility (i.e., the solubility or dispersibility of each formulation, and / or its effect on surface tension, viscosity, other printability and / or mechanical properties). Suitability is defined as "Low," indicating non-suitability for one or more of the above factors; "Medium," indicating suitability, but not in all factors; and "High," indicating suitability for most factors.

[0460] [Table 1]

[0461] (Example 2) -Hydrophobic elastomer compound- Tables 2 and 3 below show data obtained when an exemplary silicone-containing polymer material was added to an exemplary hydrophobic elastomer formulation, as described in U.S. Provisional Patent Application No. 63 / 456011, filed on March 31, 2023, and the concurrently filed PCT International Patent Application (Attorney Reference No. 99137) entitled "FORMULATIONS USABLE IN ADDITIVE MANUFACTURING OF 3D OBJECTS THAT FEATURE AN ELASTOMERIC MATERIAL".

[0462] Each of the exemplary test formulations is: - In an amount of 10% to 20% by weight relative to the total weight of the formulation, at least one monofunctional hydrophobic curable material (component A; for example, a monofunctional (meth)acrylate containing a linear aliphatic moiety with a length of at least 6 carbon atoms) having a Tg less than 0°C, according to each of the embodiments described herein and any combination thereof, - In a total amount of 40% to 70% by weight, or 50% to 60% by weight, of the total weight of the formulation, at least one, preferably at least two, monofunctional hydrophobic curable materials (component B; for example, (meth)acrylates containing an alicyclic moiety of at least six carbon atoms) according to each of the embodiments described herein and any combination thereof, each having a Tg independently of 0°C to 100°C, or 20°C to 80°C, or 20°C to 60°C, - At least one polyfunctional hydrophobic elastomer curable material (component E; for example, a polyfunctional urethane (meth)acrylate containing a polybutadiene portion) in an amount of 20% to 30% by weight, or 25% to 30% by weight, relative to the total weight of the compound, according to each of the embodiments described herein and any combination thereof, - Photopolymerization initiator, It included.

[0463] To maintain mechanical properties other than resilience, which can be adversely affected by the inclusion of silicone-containing polymer materials, some formulations are used. A polyfunctional (e.g., trifunctional) ethoxylated material (component D) having a Tg higher than 50°C or higher than 80°C (e.g., in the range of 80°C to 120°C), according to each of the embodiments described herein and any combination thereof, A curable material (component MA) (e.g., methacrylamide) containing at least two hydrogen bond-forming groups, according to each of the embodiments described herein and any combination thereof, It contained one or more of the following.

[0464] If these components (D and / or MA) are included in the test formulation, they shall be present in an amount of 0.1% to 5% by weight, or 0.1% to 3% by weight, relative to the total weight of the formulation.

[0465] The test formulations were used to print 3D objects of various shapes and dimensions suitable for each measurement, as shown below, using a system as described in Figure 1A. • Dogbone model based on ASTM D412 • Die C tensile test model based on ASTM D624 • 15 x 6 x 1.5 mm footprint model,

[0466] Table 2 shows the data obtained for printed objects.

[0467] [Table 2]

[0468] Figure 4 shows comparative plots of tensile strength as a function of elongation, determined by repeated stress-strain measurements, for the formulations shown in Table 2. It demonstrates that the addition of silicone NR improves resilience and that a synergistic effect on resilience is obtained when silicone NR is combined with the reactive silicone A component.

[0469] Table 3 shows the data obtained for the molded objects. Each test formulation was placed in a mold having the following dimensions. • Dogbone model based on ASTM D412 • Die C tensile test model based on ASTM D624

[0470] [Table 3]

[0471] The data shown in Table 3 demonstrates that adding non-reactive silicone-containing polymer materials has a beneficial effect on the resilience of elastomer objects, specifically that even a low addition amount of 2% improves resilience (see Table 3, item 6); that combining non-reactive silicone NR with reactive silicone-containing polymer materials significantly improves resilience (see Table 3, items 8-9); that low molecular weight reactive silicone-containing polymer materials are preferable to high molecular weight materials (see Table 3, items 11 and 13); and that adverse effects of silicone materials on other mechanical properties can be compensated for by adding component D (see Table 3, items 1 and 7) and / or component MA (see Table 3, items 3-5).

[0472] (Example 3) - Hydrophilic elastomer compound - Tables 4 and 5 below show data obtained when an exemplary silicone-containing polymer material was added to an exemplary hydrophilic elastomer formulation, such as one commercially available as "Elastico®".

[0473] Each of the exemplary test formulations is: - A monofunctional elastomer curable material in an amount of 50% to 70% by weight, or 55% to 65% by weight, relative to the total weight of the compound, according to each of the embodiments described herein and any combination thereof. - A polyfunctional elastomer curable material in an amount of 5% to 20% by weight relative to the total weight of the compound, according to each of the embodiments described herein and any combination thereof, - A polyfunctional non-elastomer curable material (also referred to herein as component D) in a total amount of 5% by weight or less relative to the total weight of the compound, according to any of the embodiments and any combination thereof described herein, - A monofunctional non-elastomer curable material in an amount of 15% to 25% by weight relative to the total weight of the compound, according to any of the embodiments and any combination thereof described herein, - Optionally, a curable material (e.g., component MA) containing at least two hydrogen bond-forming groups in a total amount of about 1% to about 20% by weight, or about 1% to about 10% by weight, or about 1% to about 5% by weight, based on any of the embodiments and any combination thereof described herein, - Photopolymerization initiator, It included.

[0474] The test formulations were used to print 3D objects of various shapes and dimensions suitable for each measurement, as shown below, using a system as described in Figure 1A. • Dogbone model based on ASTM D412 • Die C tensile test model based on ASTM D624 • 15 x 6 x 1.5 mm footprint model,

[0475] Table 4 shows the data obtained for printed objects.

[0476] [Table 4]

[0477] Figure 5 shows comparative plots of tensile strength as a function of elongation, determined by repeated stress-strain measurements, for the formulations shown in Table 4, demonstrating that the addition of reactive silicone-containing polymer material improves resilience.

[0478] Table 5 shows the data obtained for the molded objects. Each test formulation was placed in a mold having the following dimensions. • Dogbone model based on ASTM D412 • Die C tensile test model based on ASTM D624

[0479] The sample was cast into a silicone mold and cured in a UV oven for 10 minutes. The UV oven is equipped with 84 LEDs (wavelength = 380nm, intensity 80-100W).

[0480] [Table 5]

[0481] The data shown in Table 5 further supports the beneficial effects of reactive components such as silicone A or silicone B (preferably in amounts of 10% by weight or less), and this effect is also observed with non-reactive silicone NR (preferably in amounts of 5% by weight or less), as well as with combinations of both.

[0482] (Example 4) -Hydrophilic elastomer compound containing silica particles- Table 6 below shows data obtained when an exemplary silicone-containing polymer material was added to an exemplary hydrophilic elastomer compound, such as the one commercially available as "Agilus30®".

[0483] Each test formulation was placed into a mold having the following dimensions. • Dogbone model based on ASTM D412 • Die C tensile test model based on ASTM D624

[0484] The sample was cast into a silicone mold and cured for 10 minutes in a UV oven equipped with 84 LEDs (wavelength = 380nm, intensity 80-100W).

[0485] [Table 6]

[0486] The data shown in Table 6 indicates that a reactive component such as silicone A or silicone B (preferably in an amount of 5% by weight or less) has a beneficial effect.

[0487] Although the present invention has been described in relation to specific embodiments, it will be obvious to those skilled in the art that many alternatives, modifications, and changes will be apparent. Therefore, it is intended to encompass all such alternatives, modifications, and changes that fall within the spirit and broad scope of the appended claims.

[0488] It is the applicant's(s) intention that all publications, patents, and patent applications referenced herein be incorporated herein in their entirety by reference, as if each individual publication, patent, or patent application were specifically and individually described at the time of reference. Furthermore, no citation or specification of any reference in this application should be construed as an admission that such reference is available as prior art of the present invention. Where headings are used, they should not necessarily be construed as restrictive. In addition, the priority documents of this application are incorporated herein in their entirety by reference.

Claims

1. A curable compound that provides an elastomer material having an EDE (Efficiency Derived Exhaust) of 40% or more upon curing, At least one monofunctional elastomer curable material and / or at least one polyfunctional elastomer curable material, At least one polymeric silicone material having an average molecular weight of less than 6000 g / mol and included in an amount of 5% to 20% by weight relative to the total weight of the curable compound, A curable compound containing the above.

2. The curable compound according to claim 1, wherein the cured elastomer material has a breaking elongation of 100% or more, or 120% or more, or 180% or more, and / or a tensile strength of 1.5 MPa or more, or 1.8 MPa or more, or 2 MPa or more.

3. The curable compound according to claim 1 or claim 2, wherein the curable polymer silicone material is an amphiphilic material.

4. The curable compound according to any one of claims 1 to 3, wherein the polymer silicone material comprises at least one curable polymer silicone material and / or at least one non-curable polymer silicone material.

5. The curable compound according to claim 4, wherein the curable polymer silicone material is a bifunctional polymer silicone material.

6. The curable compound according to claim 4 or 5, wherein the curable polymer silicone material has one or more (meth)acrylate curable groups.

7. The curable compound according to claim 6, wherein the curable polymer silicone material comprises silicone polyester di(meth)acrylate.

8. The curable compound according to claim 4 or 5, wherein the curable polymer silicone material has one or more urethane (meth)acrylate curable groups.

9. The curable compound according to claim 6, wherein the curable polymer silicone material includes silicone diurethane (meth)acrylate.

10. The curable compound according to any one of claims 3 to 8, wherein the non-curable polymeric silicone material comprises a silicone polyether.

11. The curable compound according to any one of claims 1 to 10, wherein the polymer silicone material comprises at least one curable polymer silicone material and at least one non-curable polymer silicone material.

12. The curable compound according to claim 11, wherein the weight ratio of the at least one curable polymeric silicone material to the at least one non-curable polymeric silicone material is in the range of 5:1 to 1:5 or 2:1 to 1:

2.

13. The curable compound according to any one of claims 1 to 12, wherein the elastomer material is a hydrophilic elastomer material.

14. The curable compound according to claim 13, wherein the polymeric silicone material comprises at least one curable polymeric silicone material in an amount of 5% to 10% by weight relative to the total weight of the curable compound.

15. The curable compound according to claim 13 or claim 14, wherein the polymeric silicone material comprises at least one non-curable polymeric silicone material in an amount of 5% by weight or less relative to the total weight of the curable compound.

16. The curable compound according to claim 13, wherein the hydrophilic elastomer material further contains silica particles, and the polymeric silicone material contains at least one curable polymeric silicone material in an amount of 5% by weight or less relative to the total weight of the curable compound.

17. The curable compound according to any one of claims 1 to 12, wherein the elastomer material is a hydrophobic elastomer material.

18. The curable compound according to claim 17, wherein the polymeric silicone material comprises at least one non-curable polymeric silicone material in an amount of 1% to 10% by weight, or 2% to 10% by weight, or 5% to 10% by weight, preferably 5% by weight, relative to the total weight of the curable compound.

19. The curable compound according to claim 17 or claim 18, wherein the polymer silicone material comprises at least one non-curable polymer silicone material and at least one curable polymer silicone material.

20. The curable compound according to claim 19, wherein the weight ratio of the at least one curable polymer silicone material to the at least one non-curable polymer silicone material is in the range of 5:1 to 1:5 or 2:1 to 1:2, preferably in the range of 5:1 to 1:1 or 2:1 to 1:

1.

21. A curable compound according to any one of claims 1 to 20, further comprising at least one of a monofunctional non-elastomer curable material, a polyfunctional non-elastomer curable material, and a curable material containing two or more hydrogen bond-forming groups.

22. A method for manufacturing a three-dimensional object that contains an elastomer material in at least part thereof, wherein the object is formed by sequentially forming multiple layers in a configuration pattern corresponding to the shape of the object, The formation of at least a portion of each of the plurality of layers includes providing a modeling material formulation as defined in any one of claims 1 to 21, and exposing the modeling material to curing energy to form a cured modeling material, A method for manufacturing the aforementioned three-dimensional object.

23. The method according to claim 22, wherein the curing energy includes UV irradiation.

24. The method according to claim 22, wherein the additive manufacturing is performed by 3D inkjet technology.

25. The method according to claim 22, wherein the additive manufacturing is carried out by VAT polymerization technology.

26. A three-dimensional object manufactured by the method described in any one of claims 22 to 25.

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