Additive Manufacturing of Dental Prostheses

Abstract

A modeling material formulation usable for additive manufacturing of dental structures, and an additive manufacturing method using the same, are provided. Also provided are kits including the modeling material formulation, optionally in combination with a support material formulation.

Description

[Technical field]

[0001] (Related Applications) This application claims the benefit of priority under 35 USC § 119(e) of U.S. Provisional Patent Application No. 63 / 295,639, filed December 31, 2021, the contents of which are incorporated herein by reference in their entirety.

[0002] The present invention, in some embodiments thereof, relates to additive manufacturing, and more particularly to hardenable formulations that can be used for the additive manufacturing of dental prostheses, including but not limited to dentures, denture bases, and integral denture structures. [Background technology]

[0003] Additive manufacturing (AM) is a technology that allows the production of structures of arbitrary shape directly from computer data through an additive forming process. The basic operation of any AM system consists of slicing a three-dimensional computer model into thin cross sections, converting the results into two-dimensional positional data, and feeding that data to a controller to create the three-dimensional structure layer by layer.

[0004] Additive manufacturing involves many different approaches to manufacturing, including three-dimensional (3D) printing, such as 3D inkjet printing, electron beam melting, stereolithography, selective laser sintering, additive manufacturing, and fused deposition modeling.

[0005] Some 3D printing processes, such as 3D inkjet printing, are carried out by layer-by-layer inkjet deposition of a build material. Thus, the build material is ejected from an ejection head having a set of nozzles and deposited in layers on a support structure. Depending on the build material, the layers can then be cured or solidified. Curing can be by exposure to appropriate conditions and, if desired, by using an appropriate device.

[0006] Build materials include uncured model materials (also referred to as "uncured modeling materials" or "modeling material formulations") that are selectively dispensed to produce a desired object, and may also include uncured support materials (also referred to as "uncured support materials" or "support material formulations") that provide temporary support to certain areas of the object during building and ensure proper vertical positioning of subsequent object layers. The support structures are configured to be removed after the object is completed.

[0007] In some known inkjet printing systems, the uncured model material is a photopolymerizable or photocurable material that is cured, hardened, or solidified upon exposure to ultraviolet (UV) light after jetting. The uncured model material may be a photopolymerizable material formulation having a composition that, after curing, provides the solid material with mechanical properties that allow for the shaping and handling of the three-dimensional object being modeled. The modeling material formulation typically includes a reactive (hardenable) component and a photoinitiator. The photoinitiator may allow for at least partial solidification (hardening) of the uncured support material by curing with the same UV light that is applied to form the model material. The solidified material may be rigid or have elastic properties.

[0008] The support material is formulated to allow for quick and easy cleaning of the object from its support. The support material may be a polymer that is water soluble and / or capable of swelling and / or decomposing when exposed to a liquid solution, such as water, an alkaline or acidic aqueous solution. The support material formulation may also include a reactive (curable) component and a photoinitiator.

[0009] To be compatible with most commercially available print heads utilized in 3D inkjet printing systems, the uncured build material should be characterized by the following properties: a relatively low viscosity (e.g., Brookfield viscosity of up to 50 centipoise, i.e., cps, or up to 35 cps, preferably 8 cps to 25 cps) at the operating (e.g., jetting) temperature, a surface tension of about 25 dynes / cm to about 55 dynes / cm, preferably about 25 dynes / cm to about 40 dynes / cm, as well as Newtonian liquid behavior and high reactivity to the selected curing conditions to enable rapid solidification of the jetted layer when exposed to the curing conditions for 1 minute or less, preferably 20 seconds or less.

[0010] The cured modeling material that forms the final object typically exhibits a heat deflection temperature (HDT) higher than room temperature to ensure its usefulness. Desirably, the cured modeling material exhibits an HDT of at least 35° C. It is known that a higher HDT is desirable for the object to be stable under variable conditions. In many cases, it is also desirable for the object to exhibit a relatively high notched Izod impact value, for example, higher than 50 J / m, or higher than 60 J / m.

[0011] A variety of 3D printing techniques exist and are disclosed, for example, in U.S. Pat. Nos. 6,259,962, 6,569,373, 6,658,314, 6,850,334, 6,863,859, 7,183,335, 7,209,797, 7,225,045, 7,300,619, 7,500,846, 7,991,498, and 9,031,680, all by the same assignee, and U.S. Patent Application Publication No. 20160339643, which are incorporated herein by reference in their entireties.

[0012] Some additive manufacturing processes, including 3D inkjet printing, allow for additive manufacturing of objects using two or more modeling materials, also referred to as "multi-material" AM processes. For example, the assignee's U.S. Patent Application Publication No. 2010 / 0191360 discloses a system that includes a solid freeform fabrication device having multiple print heads, a build material supply device configured to supply multiple build materials to the fabrication device, and a control unit configured to control the fabrication device and the supply device. The system has several modes of operation. In one mode, all print heads operate during a single build scan cycle of the fabrication device. In another mode, one or more of the print heads are not operated during a single build scan cycle or a portion thereof.

[0013] In 3D inkjet printing processes such as Polyjet® (Stratasys Ltd®, Israel), build material is selectively jetted from one or more inkjet printheads and / or nozzles and deposited onto a production tray in successive layers according to a predetermined configuration defined by a software file.

[0014] Polyjet® technology allows control over the location and composition of each voxel (volumetric pixel), which allows for outstanding design versatility and digital programming of multi-material structures. Other advantages of Polyjet® technology are very high print resolution, layer heights of up to 14 μm, and the ability to print multiple materials simultaneously on one object. This multi-material 3D printing process is often useful for the production of complex parts and structures composed of elements with different stiffness, performance, color or transparency. A new range of materials programmed at the voxel level can be created by the Polyjet® printing process using only a few starting materials.

[0015] The assignee's WO 2013 / 128452 discloses a multi-material approach in which two components, a cationically polymerizable system and / or a radically polymerizable system, are jetted separately, and then intermixed on the print tray, resulting in a polymerization reaction similar to that achieved by premixing the two components prior to jetting, while preventing premature polymerization on the inkjet head nozzle plate.

[0016] Current Polyjet® technology offers the ability to use a variety of curable (e.g., polymerizable) materials that provide polymeric materials characterized by a variety of properties, ranging from, for example, rigid, hard materials (e.g., curable formulations commercially available as the Vero® family) to soft, flexible materials (e.g., curable formulations commercially available as the Tango® and Agilus® families). It also includes objects manufactured using Digital ABS, which includes multi-materials made from two starting materials (e.g., RGD515® and RGD535 / 531®) and simulates the properties of engineering plastics. The majority of currently commercialized Polyjet® materials are curable materials that harden or solidify when exposed to radiation (mainly UV radiation and / or heat), with the most commercialized materials being acrylic-based materials.

[0017] Some photocurable (light-polymerizable) modeling material formulations known to be usable in 3D inkjet printing are designed to provide a transparent material when cured.

[0018] The use of light-emitting diodes (LEDs) as electromagnetic radiation sources has become increasingly common and desirable in recent years in many fields, including additive manufacturing processes such as those utilizing UV-curable materials. Most commercially available UV LED sources emit UVA radiation at higher wavelengths of 365 nm / 395 nm / 405 nm. The use of such sources poses severe limitations due to the inability to efficiently use photoinitiators that absorb at shorter wavelengths, such as α-hydroxyketone-based photoinitiators that absorb at 250 nm to 300 nm. These photoinitiators are typically used for surface curing, and their absence negatively impacts process quality.

[0019] Current solutions to the limitations posed by the use of UV LEDs as the irradiation source include the use of hydrogen donors, such as tertiary amines, thiols, and polyethylene glycol-containing materials, that facilitate surface curing. However, while the use of these materials facilitates AM using UV LEDs, it comes with some drawbacks. For example, tertiary amines impart an increased yellow hue to the cured material. Thiols are generally reactive to UV-curable materials commonly used in AM, such as acrylic materials, thus limiting the shelf life of formulations that contain them. Polyethylene glycol materials are amphiphilic materials that also act as plasticizers or elastomers, reducing the mechanical stability and increasing water absorption of the resulting object.

[0020] Over the past decade, there have been efforts to use additive manufacturing, such as 3D inkjet printing and digital light processing (DLP), in the prosthetics field.

[0021] For example, US Patent No. 7,476,347 and US Patent Publication No. 2011 / 0049738 disclose a method for making a denture with integrated teeth and denture base by inkjet 3D printing. The methodologies taught in these patents use wax-like polymerizable materials that need to be custom synthesized, incurring additional time and cost. These materials require the use of more than 70% filler material and are characterized by slow reaction rates and high viscosity.

[0022] US Patent Application No. 20190175455 describes a photocurable composition for producing a dental prosthesis by stereolithography, the composition comprising a photopolymerization initiator, an acrylic monomer (X) having Mw of 200 to 800 and having no aromatic ring in one molecule but a ring structure other than an aromatic ring and two or more acryloyloxy groups, and a (meth)acrylic monomer (A) having Mw of 200 to 400 and having one or more ether bonds and two (meth)acryloyloxy groups in one molecule. and at least one of a (meth)acrylic monomer component including at least one of a (meth)acrylic monomer (B) having a ring structure other than an aromatic ring and one (meth)acryloyloxy group in one molecule and having a Mw of 130 to 240, a (meth)acrylic monomer (C) having a hydrocarbon skeleton and two (meth)acryloyloxy groups in one molecule and having a Mw of 190 to 280, and a (meth)acrylic monomer (D) having one or more aromatic rings and one (meth)acryloyloxy group in one molecule and having a Mw of 140 or more and 350 or less.

[0023] US Patent Publication No. 20180049954 teaches a photocurable composition for artificial teeth and denture bases that can be used with 3D inkjet printing or DLP type AM. The composition includes a photocurable organic compound, a surface-modified nano-sized inorganic filler, a photoinitiator, a colorant, and a stabilizer. The composition provides a distinctive denture base and a set of artificial teeth that can then be bonded together.

[0024] Further background art can be found in Chung et al., Materials (Basel) 2018 Oct. 11(10):1798, and U.S. Pat. No. 9,227,365, U.S. Pat. No. 6,242,149, U.S. Patent Application Publication No. 2010 / 0140850, WO 2009 / 013751, WO 2016 / 063282, WO 2016 / 125170, WO 2017 / 134672, WO 2018 / 134673, WO 2019 / 134674, WO 2019 / 134675, WO 2019 / 134676, WO 2019 / 134677, WO 2019 / 134678, WO 2019 / 134679 ... No. 17 / 134673, WO 2017 / 134674, WO 2017 / 134676, WO 2017 / 068590, WO 2017 / 187434, WO 2018 / 055521, WO 2018 / 055522, and WO 2020 / 065654, all of which are owned by the present assignee. Summary of the Invention

[0025] According to an aspect of some embodiments of the present invention there is provided a modeling material formulation usable for additive manufacturing of a denture structure, the modeling material formulation comprising: A polyfunctional (e.g., bifunctional) aliphatic urethane (meth)acrylate (component A) characterized by a Tg when cured of greater than 100° C.; A polyfunctional (e.g., bifunctional) non-aromatic (meth)acrylate (component B) characterized by a Tg when cured of greater than 100° C.; A filler in the form of micron-sized particles (component C), A polyfunctional (e.g., bifunctional) ethoxylated aromatic (meth)acrylate (component D), characterized by having less than 10 ethoxylated groups and / or a Tg when cured in the range of 50°C to 150°C; A monofunctional (meth)acrylate (component E), A polyfunctional (e.g., trifunctional) cyclic (meth)acrylate (component F); A polyfunctional (e.g., bifunctional) aliphatic urethane (meth)acrylate (component G) characterized in that when cured, it has a Tg of less than 100°C; Including, A modeling material formulation is provided in which the amount of the filler is 20% by weight or less, or 15% by weight or less, of the total weight of the formulation, and the amount of component D is 20% by weight or less, or 15% by weight or less, of the total weight of the formulation.

[0026] According to any of the embodiments described herein, the amount of component A ranges from 15% to 25% by weight of the total weight of the formulation.

[0027] According to any of the embodiments described herein, the amount of component B is 20 wt.% or less, or 15 wt.% or less of the total weight of the formulation.

[0028] According to any of the embodiments described herein, the total amount of the component B and the component C ranges from about 15% to about 25% by weight of the total weight of the formulation.

[0029] According to some of the embodiments described herein, Component B comprises a polyfunctional (eg, difunctional) cycloaliphatic (meth)acrylate.

[0030] According to some of the embodiments described herein, the filler particles include silica particles.

[0031] According to any of the embodiments described herein, the filler particles have a plurality of curable groups attached thereto.

[0032] According to some of the embodiments of any of the present disclosure, component D is a multifunctional ethoxylated aromatic (meth)acrylate characterized by having less than 5 ethoxylated groups.

[0033] According to any of the embodiments described herein, component D is a polyfunctional (e.g., bifunctional) ethoxylated aromatic (meth)acrylate characterized by having less than 5 ethoxylated groups and a Tg when cured in the range of 50° C. to 150° C.

[0034] According to some of the optional embodiments described herein, the monofunctional (meth)acrylate (Component E) comprises a monofunctional acrylate and a monofunctional methacrylate.

[0035] According to any of the embodiments described herein, the weight ratio of the monofunctional acrylate to the monofunctional methacrylate ranges from 2:1 to 1:2.

[0036] According to any of the embodiments described herein, the concentration of each of the monofunctional acrylate and the monofunctional methacrylate is independently in the range of 10% to 20% by weight, or 15% to 20% by weight, of the total weight of the formulation.

[0037] According to any of the embodiments described herein, the total amount of the at least one monofunctional (meth)acrylate is in the range of 30% to 40% by weight of the total weight of the formulation.

[0038] According to some of the embodiments described herein, component F is a multifunctional (eg, trifunctional) isocyanurate (meth)acrylate.

[0039] According to any of the embodiments described herein, component F is characterized by a Tg when cured greater than 150°C, or greater than 180°C, or greater than 200°C.

[0040] According to any of the embodiments described herein, the concentration or amount of component F ranges from 5% to 10% by weight of the total weight of the formulation.

[0041] According to some of the embodiments described herein, component G is a multifunctional (eg, difunctional) aliphatic urethane (meth)acrylate having an average molecular weight of at least 1000 grams / mole.

[0042] According to any of the embodiments described herein, the concentration or amount of component G ranges from 5% to 10% by weight of the total weight of the formulation.

[0043] According to any of the embodiments described herein, the formulation comprises: Component A in an amount ranging from 15% to 25% by weight of the total weight of the formulation; Component B in an amount of 20% by weight or less, or 15% by weight or less, of the total weight of the formulation; Component E in an amount of 30% to 40% by weight of the total weight of the formulation; Component F in an amount of 5% to 10% by weight of the total weight of the formulation; and said component G in an amount of 5% by weight to 10% by weight of the total weight of said blend.

[0044] According to any of the embodiments described herein, Component A is a difunctional aliphatic urethane methacrylate characterized by a Tg when cured greater than 100° C.

[0045] According to some of any of the embodiments described herein, component B is a difunctional cycloaliphatic acrylate characterized by a Tg when cured greater than 100° C.

[0046] According to some of the embodiments described herein, component C comprises micron-sized silica particles having hardenable groups attached thereto.

[0047] According to some of the optional embodiments described herein, Component D is a difunctional ethoxylated aromatic methacrylate (Component D) characterized by having less than 5 ethoxylated groups and a Tg when cured in the range of 50° C. to 150° C.

[0048] According to any of the embodiments described herein, component E comprises a monofunctional acrylate and a monofunctional methacrylate, each independently in an amount of 10% to 20% by weight or 15% to 20% by weight of the total weight of the formulation.

[0049] According to some of the embodiments described herein, component F is a trifunctional isocyanurate triacrylate.

[0050] According to some of the optional embodiments described herein, component G is a difunctional aliphatic urethane dimethacrylate characterized by a Tg when cured of less than 100° C. and an average molecular weight of at least 1000 grams / mole.

[0051] According to some of the optional embodiments described herein, the formulation further comprises a dispersant (ingredient H).

[0052] According to some of the embodiments described herein, the dispersant has a curable group.

[0053] According to some of the embodiments described herein, the dispersant is a polyfunctional aliphatic silicon (meth)acrylate.

[0054] According to some of the embodiments described herein, the dispersant has an average molecular weight of at least 1000 grams / mole.

[0055] According to some of the embodiments described herein, the amount of the dispersant ranges from 0.1% to 0.5% by weight of the total weight of the formulation.

[0056] According to any of the embodiments described herein, the formulation may further comprise a polymerization inhibitor. Further comprises (Component I).

[0057] According to some of the embodiments described herein, the formulation further comprises a photoinitiator (ingredient J).

[0058] According to any of the embodiments described herein, the amount of the photoinitiator ranges from 1% to 5% by weight of the total weight of the formulation.

[0059] According to some of the optional embodiments described herein, the formulation further comprises a colorant (ingredient P).

[0060] According to some of the embodiments described herein, the colorant comprises a pigment.

[0061] According to some of the optional embodiments described herein, the colorant comprises a mixture of a pigment and at least one (meth)acrylic material.

[0062] According to some of the embodiments described herein, the pigment comprises nano-sized particles.

[0063] According to some of the optional embodiments described herein, the colorant further comprises a pigment dispersant (component Dp).

[0064] According to one aspect of some embodiments of the present invention there is provided a support material formulation, preferably usable in combination with a modeling material formulation as defined in any one of claims 1 to 39, comprising a non-curable water-soluble or water-miscible polymeric material in an amount of about 40% to about 60% by weight of the total weight of the formulation, a hydrophilic monofunctional (meth)acrylate in an amount of 15% to 25% by weight of the total weight of the formulation, a hydrophilic monofunctional (meth)acrylamide in an amount of 10% to 20% by weight of the total weight of the formulation, and a polyfunctional non-aromatic (e.g. aliphatic or cycloaliphatic) (meth)acrylate in an amount of 1% to 5% by weight of the total weight of the formulation.

[0065] According to any of the embodiments described herein, the support material formulation further comprises a photoinitiator in an amount of 0.1% to 1% by weight of the total weight of the formulation.

[0066] According to an aspect of some embodiments of the present invention, there is provided a kit comprising at least one modeling material formulation as described in any of the respective embodiments and any combination thereof, and a support material formulation as described in any of the respective embodiments and any combination thereof, each individually packaged and contained within the kit.

[0067] According to an aspect of some embodiments of the present invention, there is provided a kit comprising at least two modeling material formulations as described in any of the respective embodiments and any combination thereof, each individually packaged and contained within the kit, wherein the at least two modeling material formulations differ from each other by the presence and / or type of colorant.

[0068] According to an aspect of some embodiments of the present invention, there is provided a method for additively manufacturing a three-dimensional denture object, comprising dispensing a plurality of layers in a configuration pattern corresponding to a shape of a denture object, thereby forming the denture object, wherein forming each of at least some of the layers comprises dispensing at least one formulation and exposing the dispensed formulation to curing conditions, thereby forming a hardened modeling material, wherein the at least one formulation is a modeling material formulation as described in any of the respective embodiments and any combination thereof.

[0069] According to any of the embodiments described herein, the dispensing comprises dispensing at least two modeling material formulations, each of which is independently a modeling material formulation described in any of the respective embodiments and any combination thereof.

[0070] According to any of the embodiments described herein, the dispensing further comprises dispensing a support material formulation.

[0071] According to any of the embodiments described herein, the support material formulation is a support material formulation described herein in any of the respective embodiments and any combination thereof.

[0072] According to some of the optional embodiments described herein, the denture structure is selected from a denture base, an artificial tooth, a plurality of artificial teeth, and a monolithic structure of a denture base and a plurality of artificial teeth.

[0073] According to any of the embodiments described herein, the denture structure is a unitary structure of a denture base and a plurality of artificial teeth.

[0074] According to an aspect of some embodiments of the present invention there is provided a denture structure obtained by an additive manufacturing (AM) process as described in any of the respective embodiments and any combination thereof.

[0075] According to any of the embodiments described herein, the denture structure is a unitary structure of a denture base and a plurality of artificial teeth.

[0076] According to any of the embodiments described herein, the denture structure is characterized by mechanical and physical properties in accordance with the requirements of ISO 20795-1 and ISO 10477, and biocompatibility in accordance with the requirements of ISO 10993-1.

[0077] Unless otherwise defined, all technical and / or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present invention, exemplary methods and / or materials are described below. In case of conflict, the patent specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and are not intended to be necessarily limiting.

[0078] Implementation of the method and / or system of the present invention may include performing or completing selected tasks manually, automatically, or a combination thereof. Further, depending on the actual instrumentation and equipment of the method and / or system of the present invention, some selected tasks may be performed by hardware, software, or firmware, or a combination thereof, using an operating system.

[0079] 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 number of software instructions executed by a computer using any suitable operating system. In an exemplary embodiment of the present invention, one or more tasks according to exemplary embodiments of the methods and / or systems described herein are performed by a data processor, such as a computing platform for executing a number 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, a network connection is also provided. Optionally, a display and / or a user device, such as a keyboard or mouse, is also provided.

[0080] Some embodiments of the present invention are described herein, by way of example only, with reference to the accompanying drawings. With particular reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for illustrative purposes of embodiments of the invention. In this regard, the description made with the aid of the drawings will make apparent to those skilled in the art how embodiments of the present invention may be practiced. [Brief description of the drawings]

[0081] [Figure 1A] FIG. 1 is a schematic diagram of an additive manufacturing system according to some embodiments of the present invention. [Figure 1B] FIG. 2 is another schematic diagram of an additive manufacturing system according to some embodiments of the present invention. [Figure 1C] FIG. 2 is another schematic diagram of an additive manufacturing system according to some embodiments of the present invention. [Figure 1D] FIG. 2 is another schematic diagram of an additive manufacturing system according to some embodiments of the present invention. [Figure 2A] FIG. 2 is a schematic diagram of a printhead according to some embodiments of the present invention. [Figure 2B] FIG. 2 is another schematic diagram of a printhead according to some embodiments of the present invention. [Figure 2C] FIG. 2 is another schematic diagram of a printhead according to some embodiments of the present invention. [Figure 3A] 1 is a schematic diagram demonstrating coordinate transformation according to some embodiments of the present invention. [Figure 3B] FIG. 13 is another schematic diagram demonstrating coordinate transformation according to some embodiments of the present invention. [Figure 4] Photographs illustrating exemplary objects made in accordance with some embodiments of the present invention, particularly the one-piece denture structures described herein. [Diagram 5] FIG. 1 is a comparative plot showing the change in mechanical properties of objects made with exemplary modeling material formulation IX described herein as measured according to ISO 20795-1. [Figure 6A] 5 shows selected areas of the interior portion of the one-piece denture as presented in FIG. 4. [Figure 6B] 6B is a bar graph showing the dimensional change over time measured according to ISO 20795-1 of hardened model material taken from selected areas, as shown in FIG. 6A, of the inner portion of the one-piece denture as presented in FIG. 4. [Figure 7A] 5 shows selected areas of the exterior portion of the one-piece denture as presented in FIG. 4. [Figure 7B]7B is a bar graph showing the dimensional change over time measured according to ISO 20795-1 of hardened model material taken from selected areas, as shown in FIG. 7A, of the outer portion of the one-piece denture as presented in FIG. 4. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0082] The present invention, in some embodiments thereof, relates to additive manufacturing, and more particularly to hardenable formulations that can be used for the additive manufacturing of dental prostheses, including but not limited to denture teeth, denture bases, and one-piece denture structures.

[0083] Before describing at least one embodiment of the invention in detail, it is to be understood that the invention is not necessarily limited in its application to the details of construction and the arrangement of components and / or methods set forth in the following description and / or illustrated in the drawings and / or examples. The invention is capable of other embodiments or of being practiced or carried out in various ways.

[0084] Throughout this specification, the term "object" refers to the final product of additive manufacturing. This term refers to the product obtained by the methods described herein after removal of the support material, if a support material is used as part of the uncured build material, and / or after post-processing (e.g., photobleaching as described herein).

[0085] As used throughout this specification, the term "object" refers to the entire object or a portion thereof.

[0086] Throughout this specification, the term "cured modeling material," also referred to herein as "hardened" or "solidified" modeling material, refers to that portion of the modeling material that forms an object when the dispensed modeling material is exposed to curing conditions (and optionally post-processing), as defined herein, and, optionally, when a support material is dispensed, when the hardened support material is removed, as described herein. The hardened modeling material can be a single hardened material or a mixture of two or more hardened materials, depending on the modeling material formulation used in the method, as described herein.

[0087] The terms "cured modeling material," "hardened modeling material," "solidified modeling material," or "cured / hardened / solidified modeling material formulation" may be considered as a hardened modeling material in which the modeling material consists only of the modeling material formulation (not including the support material formulation), i.e., the term refers to the portion of the modeling material that is used to provide the final object.

[0088] Throughout this specification, the term "modeling material formulation," also referred to interchangeably herein as "modeling formulation," "modeling material," "model material," or simply "formulation," refers to some or all of the uncured build material that is dispensed to form an object, as described herein. A modeling material formulation is an uncured modeling formulation (unless otherwise specified) that can form an object, or a portion thereof, when exposed to conditions that effect hardening.

[0089] In some embodiments of the present invention, the modeling material formulation is formulated for use in 3D inkjet printing and is capable of forming a three-dimensional object by itself, i.e., without being mixed or combined with any other substances.

[0090] The uncured modeling material can include one or more modeling material formulations and can be ejected such that different portions of the object, when cured, are made of different cured modeling formulations and thus different portions of the object are made of different cured (e.g., cured) modeling materials, or different mixtures or combinations of cured (e.g., cured) modeling materials.

[0091] The final three-dimensional object is made from the modeling material, or a combination of modeling materials, or a combination of the modeling material(s) and the support material(s), or modifications thereof (e.g., after curing), all of which are well known to those skilled in the art of solid freeform fabrication.

[0092] In some exemplary embodiments of the invention, an object is fabricated by dispensing a build material comprising two or more different modeling material formulations, where each modeling material formulation is dispensed from a different dispensing head and / or nozzle of an inkjet printing device. The modeling material formulations are optionally, but preferably, deposited in layers during the same pass of the print head. The modeling material formulations and / or combinations of formulations within a layer are selected according to the desired properties of the object and the method parameters described herein.

[0093] The uncured build material can include one or more modeling material formulations and can be ejected such that, upon curing, different portions of the model object are made of different modeling material formulations, and thus different portions of the model object are made of different cured modeling materials, or different mixtures of cured modeling materials, or a mixture of hardened modeling material and support material.

[0094] Throughout this specification, the term "hardened support material," also referred to interchangeably herein as "cured support material" or simply "support material," refers to the portion of the modeling material that is intended to support the final object produced during the manufacturing process and is removed after the process is completed to yield hardened modeling material.

[0095] Throughout this specification, the term "support material formulation," also referred to interchangeably herein as "support formulation," refers to the portion of uncured build material that is dispensed to form a support material, as described herein. A support material formulation is an uncured formulation. When the support material formulation is a curable formulation, it forms a cured support material when exposed to curing conditions.

[0096] The support material, which can be either a liquid material or a hardened, typically gel material, is also referred to herein as a sacrificial material, which can be removed after the layer has been jetted and exposed to curing energy, thereby revealing the shape of the final object.

[0097] Support materials currently in practice generally comprise a mixture of curable and non-curable materials.

[0098] Support materials currently in practical use are generally water-miscible, water-dispersible, or water-soluble.

[0099] Throughout this specification, the term "water-miscible" refers to a material that is at least partially soluble or dispersible in water, i.e., when mixed with an equal volume or weight of water at room temperature, at least 50% of the molecules migrate into the water when mixed at room temperature. This term encompasses the terms "water-soluble" and "water-dispersible."

[0100] Throughout this specification, the term "water-soluble" refers to a material that, when mixed with an equal volume or weight of water at room temperature, forms a homogeneous solution.

[0101] Throughout this specification, the term "water-dispersible" refers to a material that forms a uniform dispersion when mixed with an equal volume or weight of water at room temperature.

[0102] The method and system of the present embodiment fabricates a three-dimensional object layer-by-layer by forming multiple layers in a construction pattern corresponding to the shape of the object based on computer object data, which can be in any known format, including but not limited to Standard Tessellation Language (STL) or Stereo Lithography Contour (SLC) format, Virtual Reality Modeling Language (VRML), Additive Manufacturing File (AMF) format, Drawing Interchange Format (DXF), Polygon File Format (PLY), or any other format suitable for Computer Aided Design (CAD).

[0103] Each layer is formed by an additive manufacturing device that scans a two-dimensional surface to pattern it. During scanning, the device goes to a number of target locations on the two-dimensional layer, i.e., the surface, and determines for each target location or group of target locations whether the target location or group of target locations should be occupied by a build material formulation and what type of build material formulation should be dispensed thereto. The determination is made according to a computer image of the surface.

[0104] In preferred embodiments of the invention, AM includes 3D printing, more preferably 3D inkjet printing. In these embodiments, the build material formulation is dispensed from a dispensing head having a set of nozzles to deposit the build material formulation in layers onto a support structure. In this way, the AM device dispenses the build material formulation at target locations to be occupied and leaves other target locations empty. The device typically includes multiple dispensing heads, each of which can be configured to dispense a different build material formulation. Thus, different target locations can be occupied by different build material formulations. Types of build material formulations can be divided into two main categories: modeling material formulations and support material formulations. Support material formulations function as a support matrix or support structure to support an object or part of an object during the manufacturing process and / or for other purposes, such as providing a hollow or porous object. The support structure can further include modeling material formulation elements, for example to increase support strength.

[0105] The final three-dimensional object is made from the modeling material, a combination of modeling materials, or a combination of model and support materials, or modifications thereof (e.g., after hardening), all of which are well known to those skilled in the art of solid freeform fabrication.

[0106] In some exemplary embodiments of the invention, an object is manufactured by dispensing one or more different modeling material formulations. When more than one modeling material formulation is used, each modeling material formulation is optionally, and preferably, dispensed from a different nozzle array (belonging to the same or a different dispensing head) of the AM device.

[0107] In some embodiments, the AM device's dispensing head is a multi-channel dispensing head, where different modeling material formulations can be dispensed from two or more nozzle arrays located within the same multi-channel dispensing head. In some embodiments, the nozzle arrays dispensing the different modeling material formulations are located within separate dispensing heads, e.g., a first nozzle array dispensing a first modeling material formulation is located within the first dispensing head and a second nozzle array dispensing a second modeling material formulation is located within the second dispensing head.

[0108] In some embodiments, the nozzle array that dispenses the modeling material formulation and the nozzle array that dispenses the support material formulation are both located within the same multi-channel dispensing head, hi some embodiments, the nozzle array that dispenses the modeling material formulation and the nozzle array that dispenses the support material formulation are located within separate dispensing heads.

[0109] The build material formulations are optionally, but preferably, deposited in layers during the same pass of the print head. The build material formulations and the combination(s) of build material formulations within a layer are selected according to the desired properties of the object.

[0110] As described herein, the inventors have successfully designed, prepared and implemented a novel build material formulation that can be employed for additive manufacturing of denture structures. The newly designed formulation can be used for additive manufacturing of integrated denture structures, including denture base and artificial teeth, preferably by 3D inkjet printing.

[0111] Embodiments of the present invention relate to these newly designed modeling material formulations, supporting material formulations that can be effectively used in combination with these modeling material formulations, additive manufacturing (e.g., 3D inkjet printing) of denture structures using these formulations, and the denture structures formed thereby.

[0112] As used herein and in the art, the term "denture structure" refers to a dental prosthesis intended to replace one or more missing teeth. The denture structure includes one or more artificial teeth and a base structure for supporting the artificial tooth or teeth. The denture structure can be a partial denture, typically consisting of a denture base and one or more teeth, or a complete denture, typically consisting of a denture base and multiple teeth in the mandibular or maxillary arch. Typically, a combination of complete dentures in both the mandibular and maxillary arches is required. The denture structure is usually removable.

[0113] Embodiments of the invention encompass the additive manufacturing of artificial teeth, denture base structures, each alone, and preferably, a one-piece structure of a denture base and one or more artificial teeth. In some embodiments, the one-piece denture structure is a complete structure comprising a base structure and a set of artificial teeth for the mandibular and / or maxillary arches.

[0114] The production of such one-piece denture structures is made possible by the digital control of the color and mechanical properties of the different parts of the structure, which is made possible by the additive manufacturing methods and respective newly designed hardenable formulations described herein.

[0115] [Modeling Material Compounding:]

[0116] According to an aspect of some embodiments of the present invention there is provided a modeling material formulation usable for additive manufacturing of the denture structures described herein.

[0117] According to any of the embodiments described herein, the modeling material formulation is usable in three-dimensional (3D) inkjet printing and is such that it meets the process requirements of 3D inkjet printing, as described herein.

[0118] According to some of the embodiments described herein, the modeling material formulations described herein include one or more curable materials, also referred to herein as curable formulations, characterized in that upon exposure to the curing conditions described herein, their viscosity (e.g., at room temperature) increases by at least two times, preferably at least five times, and more preferably at least one order of magnitude.

[0119] A "hardenable material," also referred to herein as a "solidifiable material" throughout this specification, is a compound (e.g., a monomeric, oligomeric, or polymeric compound) that, upon exposure to the curing conditions (e.g., curing energy) described herein, solidifies or hardens to form a hardened modeling material as defined herein. A hardenable material is typically a polymerizable material that undergoes polymerization and / or crosslinking upon exposure to appropriate curing conditions, typically an appropriate energy source. A hardenable or hardenable material is typically such that its viscosity increases by at least one order of magnitude when exposed to curing conditions.

[0120] In some of any of the embodiments described herein, the hardenable material can be a monomer, oligomer, or short chain polymer, each of which is polymerizable and / or crosslinkable as described herein.

[0121] In some of any of the embodiments described herein, the curable material, upon exposure to curing conditions (eg, curing energy such as radiation), polymerizes by any one or combination of chain extension and crosslinking.

[0122] In some of the embodiments described herein, the curable material is a monomer or mixture of monomers that can form a polymeric modeling material upon polymerization reaction when exposed to curing conditions in which a polymerization reaction occurs. Such curable materials are also referred to herein as monomeric curable materials.

[0123] In some of the embodiments described herein, the hardenable material is an oligomer or mixture of oligomers capable of undergoing a polymerization reaction to form a polymeric modeling material when exposed to curing conditions in which a polymerization reaction occurs. Such hardenable materials are also referred to herein as oligomeric hardenable materials.

[0124] In some of the embodiments described herein, the curable material, whether monomeric or oligomeric, can be a monofunctional curable material or a multifunctional curable material.

[0125] As used herein, a monofunctional curable material contains one functional group that can undergo polymerization when exposed to curing conditions (eg, curing energy).

[0126] A multifunctional curable material comprises two or more, e.g., two, three, four or more, functional groups capable of undergoing polymerization when exposed to curing conditions. A multifunctional curable material can be, for example, a difunctional, trifunctional or tetrafunctional curable material, each of which comprises two, three or four groups capable of undergoing polymerization. The two or more functional groups in a multifunctional curable material are typically interconnected by a linkage, as defined herein. When the linkage is an oligomeric moiety, the multifunctional group is an oligomeric multifunctional curable material.

[0127] An exemplary curable material commonly used in additive manufacturing and in some of the present embodiments is an acrylic material.

[0128] As used herein, the term "acrylic materials" collectively encompasses materials having one or more acrylate, methacrylate, acrylamide, and / or methacrylamide groups.

[0129] The term "(meth)acrylate" and its grammatical diversions include materials having one or more acrylate and / or methacrylate groups.

[0130] The curable materials included in the formulations described herein may, where appropriate, be defined by the properties of the material prior to curing, including, for example, molecular weight (MW), functionality (e.g., mono- or multi-functional), and viscosity.

[0131] The curable materials included in the formulations described herein are otherwise defined by the properties provided by each material when cured. That is, the materials may be defined, where appropriate, by the properties of the material formed upon exposure to curing conditions, e.g., upon polymerization. These properties (e.g., Tg, HDT) are properties of the polymeric material formed upon curing any of the described curable materials alone.

[0132] As used herein, the term "curing" or "hardening" refers to the process by which a formulation is hardened. This term encompasses the polymerization of monomer(s) and / or oligomer(s) and / or crosslinking of polymer chains (either the polymer present prior to curing or the polymeric material formed upon polymerization of monomers or oligomers). Thus, the product of the curing reaction or hardening is typically a polymeric material, and in some cases a crosslinked polymeric material.

[0133] As used herein, "cure rate" refers to the rate at which curing occurs, i.e., the extent to which the curable material undergoes polymerization and / or crosslinking within / within a given time (e.g., 1 minute). When the curable material is a polymerizable material, the term encompasses both the mole % of the curable material in the formulation that undergoes polymerization and / or crosslinking at a given time upon exposure to curing conditions, and / or the extent to which polymerization and / or crosslinking has occurred, e.g., the extent of chain extension and / or crosslinking. Determining the polymerization rate can be performed by methods well known to those skilled in the art.

[0134] "Cure speed" can alternatively be expressed in terms of the extent to which the viscosity of a formulation charges in a given period of time, i.e., the rate at which the viscosity of the formulation increases upon exposure to curing conditions.

[0135] As used herein, the terms "conditions affecting cure" or "conditions inducing cure", also referred to interchangeably herein as "curing conditions" or "cure-inducing conditions", refer to conditions that, when applied to a formulation containing a curable material, induce at least partial polymerization of monomers and / or oligomers and / or crosslinking of polymer chains. Such conditions may include, for example, applying curing energy to the curable material and / or contacting the curable material with chemically reactive components such as catalysts, cocatalysts, and activators, as described below.

[0136] When the conditions that induce hardening include the application of hardening energy, the term "exposing to hardening conditions" means that the jetted layer, preferably each of the jetted layers, is exposed to the hardening energy, which exposure is typically performed by applying the hardening energy to the jetted layer (e.g., each layer).

[0137] "Curing energy" typically includes the application of radiation or the application of heat.

[0138] The radiation can be electromagnetic radiation (e.g., ultraviolet or visible light), or electron beam radiation, or ultrasonic radiation, or microwave radiation, depending on the material to be cured. The application (or irradiation) of radiation is carried out by a suitable radiation source. For example, as described herein, ultraviolet lamps, or visible light lamps, or infrared lamps, or xenon lamps can be used.

[0139] Curable materials, formulations or systems that undergo cure upon exposure to radiation are referred to interchangeably herein as "photopolymerizable" or "photoactivatable" or "photocurable."

[0140] In some of any of the embodiments described herein, the curable material is a photopolymerizable material that undergoes polymerization or crosslinking upon exposure to radiation as described herein, and in some embodiments, the curable material is a UV curable material that undergoes polymerization or crosslinking upon exposure to UV-visible radiation as described herein.

[0141] In some embodiments, the hardenable materials described herein include polymerizable materials that polymerize via photoinduced radical polymerization.

[0142] According to some of the optional embodiments described herein, all of the curable materials in the formulation are photocurable materials, such as (meth)acrylic materials.

[0143] According to some of the optional embodiments described herein, the modeling material formulation, when hardened, is such that it meets the requirements of common standards in the prosthetics field, such as ISO 20795-1 Dentistry, ISO 10477 Dentistry, and ISO 10993-1, as described herein.

[0144] According to some of the optional embodiments described herein, the modeling material formulation includes two or more, three or more, four or more, five or more, or all of the components described herein as Component A, Component B, Component C, Component D, Component E, Component F, and Component G (see Table 1 below), and in some of these embodiments, further includes one or more of Component H, Component I, Component J, Component P, and Component Dp (see Table 1 below).

[0145] According to any of the embodiments described herein, the modeling material formulation comprises two or more, three or more, four or more, five or more, and preferably all of the following components:

[0146] A polyfunctional (e.g., bifunctional) urethane (meth)acrylate (component A) characterized by a high Tg when cured; A polyfunctional (e.g., bifunctional) non-aromatic (meth)acrylate (component B) characterized by a high Tg when cured; A filler in the form of micron-sized particles (component C), A polyfunctional (e.g., difunctional) ethoxylated aromatic (meth)acrylate (component D); A monofunctional (meth)acrylate (component E), A polyfunctional (e.g., trifunctional) (meth)acrylate (component F); A polyfunctional (eg, difunctional) aliphatic urethane (meth)acrylate (Component G) characterized by a low Tg when cured.

[0147] According to some of the optional embodiments described herein, component A is a multifunctional (e.g., difunctional) aliphatic urethane (meth)acrylate characterized by a Tg when cured greater than 100° C.

[0148] According to some of the optional embodiments described herein, component B is a multifunctional (e.g., difunctional) non-aromatic (meth)acrylate characterized by a Tg when cured greater than 100° C.

[0149] According to some of the optional embodiments described herein, component C includes micron-sized filler particles functionalized with curable groups, as described herein.

[0150] According to some of the optional embodiments described herein, component D is a multifunctional (e.g., difunctional) ethoxylated aromatic (meth)acrylate characterized by having less than 10 ethoxylated groups and / or a Tg when cured in the range of 50° C. to 150° C.

[0151] According to some of the optional embodiments described herein, component E includes at least one or at least two monofunctional (meth)acrylates.

[0152] According to some of the embodiments of any of the embodiments described herein, component F is a multifunctional (eg, trifunctional) cyclic (meth)acrylate.

[0153] According to some of the optional embodiments described herein, component G is a polyfunctional (e.g., difunctional) aliphatic urethane (meth)acrylate characterized by a Tg when cured of less than 100° C.

[0154] According to some of the optional embodiments described herein, the amount of filler (component C) is 20% by weight or less, or 15% by weight or less of the total weight of the formulation.

[0155] According to some of the optional embodiments described herein, the amount of component D is 20 wt.% or less, or 15 wt.% or less of the total weight of the formulation.

[0156] According to some of the optional embodiments described herein, the amount of filler is 20% by weight or less, or 15% by weight or less of the total weight of the formulation, and the amount of component D is 20% by weight or less, or 15% by weight or less of the total weight of the formulation.

[0157] According to any of the embodiments described herein, the modeling material formulation comprises: A polyfunctional (e.g., bifunctional) aliphatic urethane (meth)acrylate (component A) characterized by a Tg when cured of greater than 100° C.; A polyfunctional (e.g., bifunctional) non-aromatic (meth)acrylate (component B) characterized by a Tg when cured of greater than 100° C.; A filler in the form of micron-sized particles (component C), A polyfunctional (e.g., bifunctional) ethoxylated aromatic (meth)acrylate (component D), characterized by having less than 10 ethoxylated groups and / or a Tg when cured in the range of 50°C to 150°C; A monofunctional (meth)acrylate (component E), A polyfunctional (e.g., trifunctional) cyclic (meth)acrylate (component F); and a polyfunctional (e.g., bifunctional) aliphatic urethane (meth)acrylate (component G) that, when cured, has a Tg of less than 100° C., The amount of the filler is 20% by weight or less, or 15% by weight or less of the total weight of the formulation, and the amount of component D is 20% by weight or less, or 15% by weight or less of the total weight of the formulation.

[0158] According to some of the optional embodiments described herein, the modeling material formulation includes component A as defined herein, component B1 as defined herein, component C as defined herein, component D1 as defined herein, components E1 and E2 as defined herein, component F1 as defined herein, and component G as defined herein.

[0159] According to any of the embodiments described herein, the amount of Component A described herein in any of the respective embodiments and any combination thereof, is in the range of 15% to 25% by weight of the total weight of the formulation, including any intermediate values ​​and subranges therebetween.

[0160] According to any of the embodiments described herein, the amount of each of components B and C described herein in any of the respective embodiments and any combination thereof is 20% by weight or less or 15% by weight or less of the total weight of the formulation, for example, in the range of about 5% by weight to about 20% by weight, or preferably about 5% by weight to about 15% by weight.

[0161] According to any of the embodiments described herein, the amount of component D described herein in any of the respective embodiments and any combination thereof is 20% or less by weight, or 15% or less by weight, preferably in the range of about 5% to about 20% by weight, or preferably in the range of about 5% to about 15% by weight, of the total weight of the formulation, including any intermediate values ​​and subranges therebetween.

[0162] According to any of the embodiments described herein, the total amount of component E described herein in any of the respective embodiments and any combination thereof is in the range of 30% to 40% of the total weight of the formulation, including any intermediate values ​​and subranges therebetween.

[0163] According to any of the embodiments described herein, the amount of component F described herein in any of the respective embodiments and any combination thereof, ranges from 5% to 10% by weight of the total weight of the formulation, including any intermediate values ​​and subranges therebetween.

[0164] According to any of the embodiments described herein, the amount of component G described herein in any of the respective embodiments and any combination thereof, ranges from about 5% to about 10% by weight of the total weight of the formulation, including any intermediate values ​​and subranges therebetween.

[0165] According to any of the embodiments described herein, the modeling material formulation comprises: Component A in an amount ranging from 15% to 25% by weight of the total weight of the formulation, as described herein in any of the respective embodiments and any combination thereof; Component B and Component C, each independently in an amount of 20% by weight or less or 15% by weight or less of the total weight of the formulation, as described herein in any of the respective embodiments and any combination thereof; Component D in an amount of 20% by weight or less or 15% by weight or less of the total weight of the formulation, as described herein in any of the respective embodiments and any combination thereof; Component E, as described herein in any of the respective embodiments and any combination thereof, in an amount of 30% to 40% by weight of the total weight of the formulation; Component F, as described herein in any of the respective embodiments and in any combination thereof, in an amount of 5% by weight to 10% by weight of the total weight of the formulation; and component G in an amount of 5% to 10% by weight of the total weight of the formulation, as described herein in any of the respective embodiments and any combination thereof.

[0166] According to any of the embodiments described herein, the modeling material formulation comprises: Component A in an amount ranging from 15% to 25% by weight of the total weight of the formulation, as described herein in any of the respective embodiments and any combination thereof; Component B, as described herein in any of the respective embodiments and any combination thereof, in an amount of 20% by weight or less or 15% by weight or less of the total weight of the formulation; Component C, as described herein in any of the respective embodiments and any combination thereof, in an amount of 20% by weight or less or 15% by weight or less of the total weight of the formulation; Component D in an amount of 20% by weight or less or 15% by weight or less of the total weight of the formulation, as described herein in any of the respective embodiments and any combination thereof; Component E1 and component E2 in a total amount of 30% to 40% by weight of the total weight of the formulation, as described herein in any of the respective embodiments and any combination thereof; Component F1 in an amount of 5% to 10% by weight of the total weight of the formulation, as described herein in any of the respective embodiments and any combination thereof; and component G in an amount of 5% to 10% by weight of the total weight of the formulation, as described herein in any of the respective embodiments and any combination thereof.

[0167] [Component A:]

[0168] According to some of the optional embodiments described herein, component A is a multifunctional (e.g., difunctional) urethane (meth)acrylate characterized by a Tg when cured greater than 100°C.

[0169] According to some of the optional embodiments described herein, Component A is a multifunctional (eg, difunctional) aliphatic urethane (meth)acrylate.

[0170] According to some of the optional embodiments described herein, component A is a multifunctional (e.g., difunctional) aliphatic urethane (meth)acrylate characterized by a Tg when cured greater than 100° C.

[0171] According to some of the optional embodiments described herein, component A is a difunctional urethane (meth)acrylate characterized by a Tg when cured greater than 100°C.

[0172] According to some of the optional embodiments described herein, Component A is a difunctional aliphatic urethane (meth)acrylate.

[0173] According to some of the optional embodiments described herein, component A is a difunctional aliphatic urethane (meth)acrylate characterized by a Tg when cured greater than 100°C.

[0174] According to some of the optional embodiments described herein, component A is a difunctional urethane methacrylate characterized by a Tg when cured greater than 100°C.

[0175] According to some of the optional embodiments described herein, Component A is a difunctional aliphatic urethane methacrylate.

[0176] According to some of the optional embodiments described herein, component A is a difunctional aliphatic urethane methacrylate characterized by a Tg when cured greater than 100°C.

[0177] According to some of the optional embodiments described herein, component A is characterized by a Tg when cured ranging from 100° C. to 200° C., or from 120° C. to 200° C., or from 100° C. to 150° C., or from 120° C. to 150° C., including any intermediate values ​​and subranges therebetween.

[0178] According to some of the embodiments of any of the present disclosure, the average molecular weight of component A is less than 1000 grams / mole.

[0179] Any polyfunctional aliphatic urethane (meth)acrylate is contemplated, preferably a material characterized by a toxicity profile that is acceptable for inclusion in medical devices, such as devices that contact mucosal cavities for extended periods of time, and / or in edible (e.g., food grade) products, and / or that is considered safe for extended contact with mucosal cavities.

[0180] [Component B:]

[0181] According to some of the optional embodiments described herein, component B is a multifunctional (e.g., difunctional) non-aromatic (meth)acrylate characterized by a Tg, when cured, for example, greater than 100° C.

[0182] "Non-aromatic," as defined herein, means a material that does not contain aryl groups or moieties, or heteroaryl groups or moieties.

[0183] The non-aromatic material can be, for example, aliphatic or alicyclic.

[0184] According to some of the optional embodiments described herein, component B is a multifunctional (e.g., difunctional) non-aromatic (meth)acrylate characterized by a Tg when cured, e.g., greater than 100° C., and is referred to herein as component B1.

[0185] According to some of the optional embodiments described herein, component B1 is a difunctional cycloaliphatic (meth)acrylate characterized by a Tg when cured, for example, greater than 100°C.

[0186] According to some of the optional embodiments described herein, component B1 is a difunctional cycloaliphatic acrylate or cycloaliphatic diacrylate characterized by a Tg when cured, for example, greater than 100°C.

[0187] According to some of the embodiments of any of the embodiments described herein, component B1 includes an alicyclic moiety having at least 6, 7, 8, or more carbon atoms.

[0188] According to some of the embodiments of any of the embodiments described herein, component B1 includes an alicyclic moiety that includes two, three or more fused rings.

[0189] According to some of the optional embodiments described herein, Component B or Component B1 is characterized by a Tg when cured ranging from 100° C. to 300° C., or 150° C. to 300° C., or 100° C. to 200° C., or 150° C. to 200° C., including any intermediate values ​​and subranges therebetween.

[0190] [Component C:]

[0191] According to an embodiment of the present invention, component C is a filler in particulate form comprising a plurality of particles, preferably micron-sized particles.

[0192] As used herein, the term "filler" refers to an inert material that modifies the properties of a polymeric material and / or adjusts the qualities of the final product.

[0193] Fillers (reinforcing materials) that can be used in additive manufacturing are typically inorganic particles such as, for example, silica, calcium carbonate, clay, carbon black, etc.

[0194] In some of any of the embodiments described herein, the filler is or includes silica particles.

[0195] In some embodiments, the average diameter of the particles is less than 1 micron, preferably less than 500 nm, preferably less than 200 nm, preferably less than 100 nm. In these embodiments, the silica particles are also referred to as silica nanoparticles.

[0196] In some embodiments, the average diameter of the particles ranges from 10 nm to 100 nm, or from 20 nm to 100 nm, or from 20 nm to 80 nm, or from 10 nm to 50 nm, including any intermediate values ​​and subranges therebetween.

[0197] In some embodiments, at least a portion of such particles may aggregate when introduced into the formulation, in some of these embodiments, the aggregates have an average size of a few micrometers or less.

[0198] Any commercially available formulation of submicron silica particles can be used in the context of this embodiment, including fumed silica, colloidal silica, precipitated silica, layered silica (e.g., montmorillonite), and aerosol-assisted self-assembly of silica particles.

[0199] Silica particles can be such that they are characterized by a hydrophobic or hydrophilic surface. The hydrophobicity or hydrophilicity of the particle surface is determined by the nature of the surface groups on the particle.

[0200] In a preferred embodiment, at least some or all of the silica particles are functionalized with hardenable functional groups (particles featuring hardenable groups on their surfaces).

[0201] The curable functional group can be any polymerizable group as described herein. In some embodiments, the curable functional group is polymerizable by the same polymerization reaction as the curable monomer in the formulation and / or when exposed to the same curing conditions as the curable monomer. In some embodiments, the curable group is a (meth)acrylic (acrylic or methacrylic) group as defined herein, preferably a (meth)acrylate group.

[0202] "At least a portion" as used in the context of this embodiment means at least 10%, or at least 20%, or at least 30%, or at least 40%, or at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90%, or at least 95%, or at least 98% of the particles.

[0203] In some embodiments, the silica particles are silica nanoparticles characterized by acrylate and / or methacrylate groups on their surfaces.

[0204] According to any of the embodiments described herein, component B as described herein, preferred component B1 as described herein, and component C as described herein in any of the respective embodiments are included in the formulation as a premixed composition.

[0205] According to some of these embodiments, the weight ratio of component B to component C in the premixed composition (and in formulations containing the same) is about 1:1.

[0206] According to some of the optional embodiments described herein, the total amount of Component B (e.g., Component B1) and Component C ranges from about 15% to about 30% by weight, or from about 15% to about 25% by weight, or from about 2% to about 25% by weight, or from about 20% to about 30% by weight of the total weight of the formulation, including any intermediate values ​​and subranges therebetween.

[0207] [Component D:]

[0208] According to some of the embodiments described herein, component D is a multifunctional ethoxylated (meth)acrylate.

[0209] According to some of the optional embodiments described herein, component D is a multifunctional (e.g., difunctional) ethoxylated aromatic (meth)acrylate that contains one or more aromatic (aryl or heteroaryl) moieties.

[0210] According to some of the optional embodiments described herein, component D comprises a bisphenol A moiety as a branching unit with two or three ethoxylated moieties terminating in (meth)acrylate groups extending from the branching unit.

[0211] According to some of the optional embodiments described herein, component D is a difunctional ethoxylated aromatic (meth)acrylate.

[0212] According to some of the optional embodiments described herein, component D is a multifunctional (e.g., difunctional) ethoxylated aromatic (meth)acrylate characterized by a Tg when cured of less than 200° C.

[0213] According to any of the embodiments described herein, component D is a multifunctional (e.g., difunctional) ethoxylated aromatic (meth)acrylate characterized by a Tg when cured ranging from 50° C. to 150° C., including any intermediate values ​​and subranges therebetween.

[0214] According to any of the embodiments described herein, component D is a difunctional ethoxylated aromatic (meth)acrylate characterized by a Tg when cured ranging from 50° C. to 150° C., including any intermediate values ​​and subranges therebetween.

[0215] According to any of the embodiments described herein, component D is a multifunctional (e.g., difunctional) ethoxylated aromatic methacrylate characterized by a Tg when cured ranging from 50° C. to 150° C., including any intermediate values ​​and subranges therebetween.

[0216] According to some of the optional embodiments described herein, component D is a difunctional ethoxylated aromatic methacrylate (ethoxylated aromatic dimethacrylate) characterized by a Tg when cured ranging from 50° C. to 150° C., including any intermediate values ​​and subranges therebetween.

[0217] According to some of the embodiments of any of the embodiments described herein, component D includes fewer than 10, or fewer than 8, or fewer than 6, or fewer than 5 ethoxylated moieties.

[0218] According to some of the embodiments described herein, component D comprises a total of four ethoxylated moieties.

[0219] According to some of the optional embodiments described herein, component D is a polyfunctional (e.g., difunctional) ethoxylated aromatic (meth)acrylate characterized by a Tg when cured in the range of 50° C. to 150° C., including any intermediate values ​​and subranges therebetween, and / or containing less than 10 ethoxylated moieties, or less than 8, or less than 6, or less than 5 ethoxylated moieties, such as 4 ethoxylated moieties. Such components are referred to herein as component D1.

[0220] According to some of the optional embodiments described herein, component D1 is a multifunctional (e.g., difunctional) ethoxylated aromatic (meth)acrylate characterized by a Tg when cured in the range of 50° C. to 150° C., including any intermediate values ​​and subranges therebetween, and containing fewer than 10 ethoxylated moieties, or fewer than 8, or fewer than 6, or fewer than 5 ethoxylated moieties, such as 4 ethoxylated moieties.

[0221] According to some of the optional embodiments described herein, component D1 is a difunctional ethoxylated aromatic (meth)acrylate characterized by a Tg when cured in the range of 50° C. to 150° C., including any intermediate values ​​and subranges therebetween, and containing less than 10 ethoxylated moieties, or less than 8, or less than 6, or less than 5 ethoxylated moieties, for example 4 ethoxylated moieties.

[0222] According to some of the optional embodiments described herein, component D1 is a multifunctional (e.g., difunctional) ethoxylated aromatic methacrylate characterized by a curing temperature when cured ranging from 50° C. to 150° C., including any intermediate values ​​and subranges therebetween, and containing less than 10 ethoxylated moieties, or less than 8, or less than 6, or less than 5 ethoxylated moieties, such as 4 ethoxylated moieties.

[0223] According to some of the optional embodiments described herein, component D1 is a difunctional ethoxylated aromatic methacrylate characterized by a curing temperature when cured ranging from 50° C. to 150° C., including any intermediate values ​​and subranges therebetween, and containing less than 10 ethoxylated moieties, or less than 8, or less than 6, or less than 5 ethoxylated moieties, for example 4 ethoxylated moieties.

[0224] [Component E:]

[0225] According to some of the optional embodiments described herein, Component E includes one or more monofunctional (meth)acrylate materials.

[0226] According to some of the optional embodiments described herein, Component E includes two or more monofunctional (meth)acrylate materials.

[0227] According to some of the optional embodiments described herein, Component E comprises two or more monofunctional (meth)acrylate materials, at least one of which is a monofunctional acrylate, also referred to herein as Component E1, and at least one of which is a monofunctional methacrylate, also referred to herein as Component E2.

[0228] According to some of the embodiments described herein, each of the monofunctional materials has an average molecular weight of less than 1000 grams / mole, or less than 500 grams / mole.

[0229] According to some of the optional embodiments described herein, at least one of component E1 and component E2, or both, is a hydrophilic and / or amphiphilic material.

[0230] As used throughout this specification, the term "hydrophilic" refers to a physical property of a material or a portion of a material (e.g., a chemical group in a compound) that describes the temporary formation of bonds with water molecules, typically through hydrogen bonds.

[0231] A hydrophilic material dissolves more readily in water than in oil or other hydrophobic solvents. A hydrophilic material can be defined, for example, as having a LogP of less than 0.5 when the LogP is determined in the octanol and water phases.

[0232] Hydrophilic materials may alternatively or additionally be defined as being characterized by a hydrophile-lipophile balance (HLB) of at least 10, or at least 12, according to the Davies method.

[0233] As used throughout this specification, the term "amphiphilic" refers to the property of a material that combines both hydrophilicity, as described herein for hydrophilic materials, and hydrophobicity or lipophilicity, as defined herein for hydrophobic materials.

[0234] 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).

[0235] An amphiphilic material can be defined, for example, as having a LogP of 0.8 to 1.2, or about 1, when the LogP is determined in octanol and aqueous phases.

[0236] Amphiphilic materials may alternatively or additionally be defined as being characterized by a lipophilic / hydrophilic balance (HLB) of 3-12, or 3-9, according to the Davies method.

[0237] Hydrophilic materials or portions of materials (eg, chemical groups in a chemical compound) are typically charge polarized and capable of hydrogen bonding.

[0238] Amphiphilic materials typically contain, in addition to hydrophobic groups, one or more hydrophilic groups (eg, charge polarizable groups).

[0239] Hydrophilic materials or hydrophilic groups, and amphiphilic materials typically contain one or more electron-donating heteroatoms that form strong hydrogen bonds with water molecules. Such heteroatoms include, but are not limited to, oxygen and nitrogen. Preferably, the ratio of the number of carbon atoms to the number of heteroatoms in the hydrophilic materials or hydrophilic groups is 10:1 or less, such as 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 be due to the ratio between the hydrophobic and hydrophilic moieties in the materials or chemical groups, and do not depend only on the above ratio.

[0240] A hydrophilic or amphiphilic material can have one or more hydrophilic groups or moieties. Hydrophilic groups are typically polar groups that contain one or more electron-donating heteroatoms such as oxygen and nitrogen.

[0241] Exemplary hydrophilic groups include, but are not limited to, electron donating heteroatoms, carboxylates, thiocarboxylates, oxo (=O), linear amides, hydroxy, alkoxy (1-4 carbon atoms), alcohols (1-4 carbon atoms), alicyclic heterocycles (aliphatic heterocycles / heterocycles, heteroalicyclic) (e.g., having a ratio of carbon atoms to heteroatoms 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 polymeric or oligomeric moieties, and any combination thereof (e.g., hydrophilic groups comprising two or more of the exemplary hydrophilic groups), as defined herein.

[0242] In some embodiments, the hydrophilic group is or includes an electron donating heteroatom, a carboxylate, an alicyclic heterocycle, an alkylene glycol, and / or a hydrophilic oligomeric moiety.

[0243] An amphiphilic moiety or group typically comprises one or more hydrophilic groups and one or more hydrophobic groups as described herein, or may be a heteroatom-containing group or moiety where the ratio of the number of carbon atoms to the number of heteroatoms determines the amphiphilicity.

[0244] The hydrophilic or amphiphilic monofunctional curable material according to some embodiments of the present invention may be a hydrophilic acrylate represented by formula A1.

[0245] [ka]

[0246] wherein R1 and R2 are as defined herein and at least one of R1 and R2 is and / or includes a hydrophilic or amphiphilic moiety or group as defined herein.

[0247] In some of these optional embodiments, the carboxylate group -C(=O)-ORa includes a hydrophilic or amphiphilic moiety or group, Ra, as defined herein. Exemplary Ra groups in the context of these embodiments include, but are not limited to, alicyclic heterocyclic groups (such as morpholine, tetrahydrofuran, oxalidine, etc., having a ratio of carbon atoms to electron donating heteroatoms of 10:1 or less, or 8:1 or less, or 6:1 or less, or 5:1 or less), hydroxyl, alkoxy having 1 to 4 carbon atoms, thiol, alkylene glycol, or a hydrophilic or amphiphilic polymeric or oligomeric moiety, as described herein. An exemplary hydrophilic monomeric monofunctional acrylate is acryloylmorpholine (ACMO).

[0248] Exemplary hydrophilic or amphiphilic oligomeric monofunctional curable materials include, but are not limited to, mono-(meth)acrylate urethane oligomer derivatives of polyethylene glycol, mono-(meth)acrylate polyol oligomers, mono-(meth)acrylate oligomers with hydrophilic substituents, mono-(meth)acrylate polyethylene glycols (e.g., methoxypolyethylene glycols), and mono-urethane acrylates.

[0249] According to some of the optional embodiments described herein, component E1 is a hydrophilic or amphiphilic monofunctional methacrylate.

[0250] According to some of the embodiments described herein, component E2 is a monofunctional acrylate, which in some embodiments is a monofunctional acrylate having an alicyclic group as Ra in formula A1.

[0251] According to some of the optional embodiments described herein, component E1 is a hydrophilic or amphiphilic monofunctional methacrylate, and component E2 is a monofunctional acrylate, which in some embodiments is a monofunctional acrylate having an alicyclic structure as Ra in formula A1.

[0252] According to some of the embodiments described herein, the weight ratio of the monofunctional methacrylate (E1) to the monofunctional acrylate (E2) ranges from 2:1 to 1:2, or is about 1:1.

[0253] According to some of the optional embodiments described herein, the amount of each of the monofunctional acrylate (E2) and the monofunctional methacrylate (E1) is independently in the range of 10% to 20% by weight, or 15% to 20% by weight, of the total weight of the formulation.

[0254] According to some of the embodiments described herein, the total amount of the one or more monofunctional (meth)acrylate(s) (e.g., E1 and E2) is in the range of 30% to 40% by weight of the total weight of the formulation, including any intermediate values ​​and subranges therebetween.

[0255] According to some of the optional embodiments described herein, at least one or both of the monofunctional acrylate (E2) and the monofunctional methacrylate (E1) are characterized by a Tg, when cured, of less than 100° C., or less than 80° C.

[0256] [Component F:]

[0257] According to some of the embodiments described herein, component F is a trifunctional (meth)acrylate.

[0258] According to some of the optional embodiments described herein, component F is a multifunctional (e.g., trifunctional) (meth)acrylate characterized by a Tg when cured greater than 150° C., or greater than 180° C., or greater than 200° C.

[0259] According to some of the optional embodiments described herein, component F is a polyfunctional (e.g., trifunctional) cyclic (meth)acrylate containing one or more cyclic moieties, such as aryl and / or alicyclic, also referred to herein as component F1.

[0260] According to some of the optional embodiments described herein, component F1 is a trifunctional cyclic (meth)acrylate that contains one or more cyclic moieties, such as aryl and / or alicyclic.

[0261] According to some of the embodiments of any of the embodiments described herein, component F1 is a trifunctional cyclic methacrylate or cyclic trimethacrylate containing one or more cyclic moieties, such as aryl and / or alicyclic.

[0262] According to some of the optional embodiments described herein, component F or component F1 is characterized by a Tg when cured, for example, greater than 100° C., or greater than 150° C., or greater than 200° C., or even greater than 250° C.

[0263] According to some of the optional embodiments described herein, component F1 is a trifunctional cyclic methacrylate or cyclic trimethacrylate, which contains one or more cyclic moieties, such as aryl and / or cycloaliphatic, and is characterized by a high Tg when cured, for example, greater than 100° C., or greater than 150° C., or greater than 200° C., or even greater than 250° C.

[0264] In some of the embodiments of any of component F or component F1, the cyclic moiety is a branched unit as defined herein.

[0265] In some of the embodiments of any of Component F or Component F1, the cyclic moiety is or includes a cyanurate or an isocyanurate.

[0266] In some of the embodiments of any of Component F or Component F1, the cyclic moiety is or includes a cyanurate or isocyanurate and is a branched unit from which extends a moiety that includes a (meth)acrylate group.

[0267] [Component G:]

[0268] According to some of the embodiments described herein, component G is a polyfunctional (e.g., difunctional) aliphatic urethane (meth)acrylate having an average molecular weight of at least 1000 grams / mole. Such components are also referred to herein as oligomeric curable materials.

[0269] According to some of the optional embodiments described herein, component G is a difunctional aliphatic urethane (meth)acrylate having an average molecular weight of at least 1000 grams / mole.

[0270] According to some of the optional embodiments described herein, component G is a multifunctional (eg, difunctional) aliphatic urethane methacrylate having an average molecular weight of at least 1000 grams / mole.

[0271] According to some of the optional embodiments described herein, component G is a difunctional aliphatic urethane methacrylate having an average molecular weight of at least 1000 grams / mole.

[0272] According to some of the optional embodiments described herein, component G is characterized by having a low Tg when cured.

[0273] According to some of the optional embodiments described herein, component G is characterized by a Tg when cured of less than 100°C, or less than 80°C.

[0274] According to some of the embodiments described herein, component G is a non-polar (e.g., non-hydrophilic or hydrophobic) polyfunctional (e.g., difunctional) aliphatic urethane (meth)acrylate described herein.

[0275] [Exemplary formulations:]

[0276] According to an exemplary embodiment, the modeling material formulation comprises: Component A, as described herein in any of the respective embodiments and any combination thereof, in an amount ranging from 15% by weight to 25% by weight of the total weight of the formulation; Component B, preferably component B1, as described herein in any of the respective embodiments and any combination thereof, in an amount of 20% by weight or less or 15% by weight or less of the total weight of the formulation; Component C, as described herein in any of the respective embodiments and any combination thereof, in an amount of 20% by weight or less or 15% by weight or less of the total weight of the formulation; Component D, preferably component D1, as described herein in any of the respective embodiments and any combination thereof, in an amount of 20% by weight or less or 15% by weight or less of the total weight of the formulation; Component E, preferably a mixture of components E1 and E2, as described herein in any of the respective embodiments and any combination thereof, in a total amount of 30% by weight to 40% by weight of the total weight of the total amount of the formulation; Component F, preferably component F1, as described herein in any of the respective embodiments and any combination thereof, in an amount of 5% by weight to 10% by weight of the total weight of the formulation; and component G, as described herein in any of the respective embodiments and any combination thereof, in an amount of 5% to 10% by weight of the total weight of the formulation.

[0277] According to an exemplary embodiment, the modeling material formulation comprises: As component A, a difunctional aliphatic urethane methacrylate characterized by having a Tg of more than 100°C when cured; Component B1 is a difunctional alicyclic acrylate having a Tg of more than 100° C. when cured; As component C, silica particles having a curable group bonded thereto; Component D is a bifunctional ethoxylated aromatic methacrylate having less than 5 ethoxylated groups and a Tg in the range of 50 to 150°C when cured; as component E, a monofunctional acrylate (E2) and a monofunctional methacrylate (E1), each independently in an amount of 10% to 20% by weight, or 15% to 20% by weight, of the total weight of the formulation; Component F1, which is a trifunctional isocyanurate triacrylate; Component G includes a difunctional aliphatic urethane dimethacrylate characterized by a Tg when cured of less than 100° C. and an average molecular weight of at least 1000 grams / mole.

[0278] According to an exemplary embodiment, the modeling material formulation comprises: Component A is a difunctional aliphatic urethane methacrylate characterized by a Tg when cured greater than 100° C. in an amount ranging from 15% to 25% by weight of the total weight of the formulation; Component B1, which is a difunctional cycloaliphatic acrylate characterized by a Tg of greater than 100° C. when cured, in an amount of 20% by weight or less or 15% by weight or less of the total weight of the formulation; As component C, silica particles having hardenable groups attached thereto in an amount of 20% by weight or less, or 15% by weight or less, based on the total weight of the formulation; Component D1, which is a difunctional ethoxylated aromatic methacrylate having less than 5 ethoxylated groups and a Tg when cured in the range of 50°C to 150°C, in an amount of 20% by weight or less or 15% by weight or less of the total weight of the formulation; As component E, a monofunctional acrylate (E2) and a monofunctional methacrylate (E1) in a total amount of 30% by weight to 40% by weight of the total weight of the formulation, each independently being 10% by weight to 20% by weight, or 15% by weight to 20% by weight of the total weight of the formulation; Component F1, which is a trifunctional isocyanurate triacrylate in an amount of 5% to 10% by weight of the total weight of the formulation; and Component G, a difunctional aliphatic urethane dimethacrylate characterized by a Tg when cured of less than 100° C. and an average molecular weight of at least 1000 grams / mole in an amount of 5% to 10% by weight of the total weight of the formulation.

[0279] According to some of the optional embodiments described herein, the modeling material formulation is such that it does not include methyl methacrylate and / or methyl acrylate, and / or the cured modeling material does not include poly(methyl methacrylate) (PMMA).

[0280] Throughout this specification, "devoid of" means less than 1%, or less than 0.1%, or less than 0.01%, or less than 0.001%, or zero.

[0281] [Additional ingredients:]

[0282] According to some of the optional embodiments described herein, the modeling material formulation further comprises a dispersant (component H).

[0283] According to some of these embodiments, the dispersant is characterized by a curable group, preferably a (meth)acrylic group.

[0284] According to some of the embodiments described herein, the dispersing agent is a polyfunctional (e.g., difunctional) aliphatic silicon (meth)acrylate.

[0285] According to some of the optional embodiments described herein, the dispersing agent is a difunctional aliphatic silicon (meth)acrylate.

[0286] According to some of the embodiments described herein, the dispersing agent is a polyfunctional (e.g., difunctional) aliphatic silicone acrylate.

[0287] According to some of the embodiments described herein, the dispersant is a difunctional aliphatic silicone acrylate.

[0288] According to some of the optional embodiments described herein, the dispersant has an average molecular weight of at least 1000 grams / mole, or at least 2000 grams / mole, or at least 3000 grams / mole, and is considered an oligomeric material.

[0289] According to some of the embodiments described herein, the dispersing agent is a polyfunctional (e.g., difunctional) aliphatic silicon (meth)acrylate as described herein having an average molecular weight of at least 1000 grams / mole.

[0290] According to some of the embodiments described herein, the dispersing agent is a difunctional aliphatic silicon (meth)acrylate having an average molecular weight of at least 1000 grams / mole, as described herein.

[0291] According to some of the embodiments described herein, the dispersing agent is a polyfunctional (e.g., difunctional) aliphatic silicone acrylate as described herein having an average molecular weight of at least 1000 grams / mole.

[0292] According to some of the embodiments of any of the present disclosure, the dispersing agent is a difunctional aliphatic silicone acrylate as described herein having an average molecular weight of at least 1000 grams / mole.

[0293] According to any of the embodiments described herein, the dispersant is characterized by a low Tg when cured, preferably less than 0°C, or less than -20°C, or less than -50°C.

[0294] According to any of the embodiments described herein, the amount of dispersant ranges from 0.1% to 0.5% by weight of the total weight of the formulation, including any intermediate values ​​and subranges therebetween.

[0295] According to some of the optional embodiments described herein, the modeling material formulation further comprises a polymerization inhibitor (Component I) as described herein, such as a phenolic type polymerization inhibitor, or any other polymerization inhibitor commonly used in medical devices or applications and / or in food products.

[0296] According to any of the embodiments described herein, the amount of polymerization inhibitor ranges from 0.001% to 0.010% by weight of the total weight of the formulation, including any intermediate values ​​and subranges therebetween.

[0297] According to some of the optional embodiments described herein, the modeling material formulation further includes at least one photoinitiator (Component J).

[0298] According to any of the embodiments described herein, the amount of photoinitiator ranges from 1% to 5% by weight of the total weight of the formulation, including any intermediate values ​​and subranges therebetween.

[0299] According to some of the optional embodiments described herein, the photoinitiator(s) comprise or consist essentially of a phosphine oxide type (e.g., monoacrylated (MAPO) or bisacrylated phosphine oxide type (BAPO)) photoinitiator.

[0300] Exemplary monoacyl and bisacyl phosphine oxides include, but are not limited to, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,4,6 trimethylbenzoyl)phenylphosphine oxide, dibenzoylphenylphosphine oxide, bis(2,6-dimethoxybenzoyl)phenylphosphine oxide, tris(2,4-dimethylbenzoyl)phosphine oxide, tris(2-methoxybenzoyl)phosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,3,5,6-tetramethylbenzoyldiphenylphosphine oxide, benzoyl-bis(2,6-dimethylphenyl)phosphonate, and 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide. Commercially available phosphine oxide photoinitiators capable of free radical initiation when irradiated in the wavelength range from about 380 nm to about 450 nm include 2,4,6-trimethylbenzoyldiphenylphosphine oxide (TPO), bis(2,4,6 trimethylbenzoyl)phenylphosphine oxide (commercially available as IRGACURE® 819), bis(2,6-dimethoxybenzoyl)-(2,4,4 trimethylpentyl)phosphine oxide (commercially available as CGI 403), and bis(2,6-dimethoxybenzoyl)-(2,4,4 trimethylpentyl)phosphine oxide (commercially available as CGI 403). Examples of suitable phosphine oxides include a 25:75 by weight mixture of bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide and 2-hydroxy-2-methyl-1-phenylpropan-1-one (commercially available as IRGACURE® 1700), a 1:1 by weight mixture of bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide and 2-hydroxy-2-methyl-1-phenylpropan-1-one (commercially available as DAROCUR® 4265), and ethyl 2,4,6-trimethylbenzylphenylphosphinate (LUCIRIN LR8893X).

[0301] In an exemplary embodiment, the photoinitiator is or includes bis(2,4,6 trimethylbenzoyl)phenylphosphine oxide (commercially available as IRGACURE® 819).

[0302] In an exemplary embodiment, the photoinitiator does not include 2,4,6-trimethylbenzoyldiphenylphosphine oxide (commercially available as TPO) and / or bis(2,4,6 trimethylbenzoyl)phenylphosphine oxide (commercially available as IRGACURE® 819).

[0303] According to some of the optional embodiments described herein, the modeling material formulation is a clear (e.g., transparent) colorless formulation that does not contain colorants.

[0304] According to some of the optional embodiments described herein, the modeling material formulation further comprises one or more colorants (component P).

[0305] The colorant can be a pigment or a dye, with pigments being preferred.

[0306] The pigments can be organic and / or inorganic and / or metallic pigments, and in some embodiments, the pigments are nanoscale pigments, including nanoparticles.

[0307] Exemplary inorganic pigments include titanium oxide and / or zinc oxide and / or silica nanoparticles. Exemplary organic pigments include nano-sized carbon black.

[0308] In some embodiments, a combination of white and colored pigments is used to prepare the colored cured material.

[0309] According to some of the optional embodiments described herein, the colorant comprises a mixture of a pigment and at least one (meth)acrylic material such that the pigment is introduced into the formulation in the mixture.

[0310] According to some of the optional embodiments described herein, the pigment is a white pigment and the formulation provides a white cured material.

[0311] According to some of the optional embodiments described herein, the colorant comprises a mixture of a white pigment and one or more curable materials, such as (meth)acrylic materials, such that the pigment is introduced into the formulation in a mixture.

[0312] According to some of these embodiments, the amount of white pigment in the mixture ranges from 20% to 50% by weight of the total weight of the mixture, including any intermediate values ​​and subranges therebetween.

[0313] According to some of these embodiments, the amount of colorant, which is a mixture of a white pigment and at least one (meth)acrylic material, ranges from 1% to 5% by weight of the total weight of the formulation.

[0314] According to some of the optional embodiments described herein, the pigment is a cyan pigment and the formulation provides a cyan cured material.

[0315] According to some of the optional embodiments described herein, the colorant comprises a mixture of a cyan pigment and one or more curable materials, such as (meth)acrylic materials, such that the pigments are introduced into the formulation in a mixture.

[0316] According to some of these embodiments, the amount of cyan pigment in the mixture ranges from 0.01 wt % to 1 wt %, or from 0.05 wt % to 0.5 wt %, or from 0.1 wt % to 0.2 wt %, of the total weight of the mixture.

[0317] According to some of these embodiments, the amount of the colorant, which is a mixture of a cyan pigment and at least one (meth)acrylic material, ranges from 0.1% to 1% by weight of the total weight of the formulation.

[0318] According to some of the optional embodiments described herein, the pigment is a yellow pigment and the formulation provides a yellow cured material.

[0319] According to some of the optional embodiments described herein, the colorant comprises a mixture of a yellow pigment and one or more curable materials, such as (meth)acrylic materials, such that the pigments are introduced into the formulation in a mixture.

[0320] According to some of these embodiments, the amount of yellow pigment in the mixture ranges from 0.01 wt % to 1 wt %, or from 0.05 wt % to 0.5 wt %, or from 0.1 wt % to 0.2 wt % of the total weight of the mixture.

[0321] According to some of these embodiments, the amount of the colorant, which is a mixture of a yellow pigment and at least one (meth)acrylic material, ranges from 0.1% to 1% by weight of the total weight of the formulation.

[0322] According to some of the optional embodiments described herein, the pigment is a magenta pigment and the formulation provides a magenta cured material.

[0323] According to some of the optional embodiments described herein, the colorant comprises a mixture of a magenta pigment and one or more curable materials, such as (meth)acrylic materials, such that the magenta pigment is introduced into the formulation in the mixture.

[0324] According to some of these embodiments, the amount of magenta pigment in the mixture ranges from 0.01% to 1% by weight, or from 0.05% to 0.5% by weight, or from 0.1% to 0.2% by weight of the total weight of the mixture.

[0325] According to some of these embodiments, the amount of the colorant, which is a mixture of a magenta pigment and at least one (meth)acrylic material, ranges from 0.1% by weight to 1% by weight of the total weight of the formulation.

[0326] According to some of the optional embodiments described herein, the formulation includes one or more of a white colorant, a magenta colorant, a cyan colorant, and a yellow colorant, and in some of these embodiments, each pigment is introduced into the formulation in admixture with the curable material described herein.

[0327] According to some of the optional embodiments described herein, the colorant further comprises a pigment dispersant (component Dp). Preferred pigment dispersants are those that have multiple groups that characterize their affinity for the pigment.

[0328] According to some of the optional embodiments described herein, the modeling material formulation includes component H, component I, and component J, as described herein in any of the respective embodiments. An exemplary such formulation is a clear, colorless formulation that does not contain any colorant.

[0329] According to some of the optional embodiments described herein, the modeling material formulation includes component H, component I, component J, and component P as described herein in any of the respective embodiments. An exemplary such formulation is a white formulation including a white pigment as described herein.

[0330] According to some of the optional embodiments described herein, the modeling material formulation includes component H, component I, component J, component P, and component Dp, as described herein in any of the respective embodiments. Exemplary such formulations are the cyan, magenta, and yellow formulations described herein.

[0331] [kit:]

[0332] In some of the embodiments described herein, kits are provided that include one or more of the modeling material formulations described herein in any of the respective embodiments and any combination thereof.

[0333] In some of the embodiments of any of the embodiments described herein, a kit is provided that includes two or more of the modeling material formulations described herein in any of the respective embodiments and any combination thereof, in some of these embodiments, each formulation is packaged separately within the kit.

[0334] In an exemplary embodiment, the kit includes a combination of two or more formulations that differ from one another in the presence and / or type of colorant or pigment.

[0335] In an exemplary embodiment, the kit includes two or more of the clear, white, cyan, magenta and yellow formulations described herein in any of the respective embodiments.

[0336] The kits described herein can be used for additive manufacturing of the denture structures described herein, particularly the one-piece denture structures described herein.

[0337] In exemplary embodiments, the formulation is packaged in a kit with a suitable packaging material, preferably an impermeable material (e.g., a water and gas impermeable material), more preferably an opaque material. In some embodiments, the kit further comprises instructions for using the formulation in an additive manufacturing process, preferably a 3D inkjet printing process as described herein. The kit may further comprise instructions for using the formulation in a process according to the methods described herein.

[0338] According to some of the embodiments relating to the kit, the kit may further include a support material formulation. For example, any support material formulation usable in AM, such as 3D inkjet printing, is contemplated.

[0339] According to some of these embodiments, the support material formulation is as described herein in any of the respective embodiments.

[0340] [Support material formulation:]

[0341] The present inventors have designed and successfully implemented a support material formulation suitable for use with the modeling material formulation of the present embodiment.

[0342] According to some embodiments of this aspect of the invention, the support material formulation comprises: a non-curable water-soluble or water-miscible polymeric material in an amount of about 40% to about 60% by weight of the total weight of the formulation; a hydrophilic monofunctional (meth)acrylate in an amount of 15% to 25% by weight of the total weight of the formulation; a hydrophilic monofunctional (meth)acrylamide in an amount of 10% to 20% by weight of the total weight of the formulation; a polyfunctional non-aromatic (e.g., aliphatic or cycloaliphatic) (meth)acrylate in an amount of 1 wt.% to 5 wt.% of the total weight of the formulation; Includes.

[0343] According to some of these optional embodiments, the non-curable polymeric material includes a polyol.

[0344] As used herein and in the art, the term "polyol" refers to a polymeric material characterized by two or more free hydroxy groups, typically from about 10 to tens or hundreds of free hydroxy groups. Representative examples of polyols include, but are not limited to, polyester polyols, polyether polyols, and urethane polyols. Preferably, the polyol is a polyether polyol, such as, for example, poly(alkylene glycol).

[0345] The polyol can be a linear polyol or a polyol that is not linear (eg, a branched polyol).

[0346] According to some of the embodiments described herein, the polyol is a poly(alkylene glycol), such as poly(ethylene glycol) or poly(propylene glycol), or a mixture thereof. In some embodiments, the polyol is or includes poly(propylene glycol).

[0347] According to some of the embodiments described herein, the polyol comprises an alkoxylated branched polyol, for example, commercially available as Polyol 3165.

[0348] According to some of the embodiments described herein, the polyol has an average molecular weight of less than 1200 grams / mole, or less than 1000 grams / mole.

[0349] The average molecular weight of the polyol can range from about 200 to about 1100, or from about 400 to about 1100, including any intermediate values ​​and subranges therebetween.

[0350] According to some of the optional embodiments described herein, the support material formulation further comprises a non-curing water-soluble or water-miscible non-polymeric material, such as a diol or triol or glycerol. In an exemplary embodiment, this is a diol, such as propanediol.

[0351] According to some of the embodiments described herein, the support material formulation comprises a mixture of polymeric and non-polymeric materials described herein, which in some of these embodiments comprises a mixture of poly(alkylene glycols), branched polyols, and diols, in some embodiments, the total amount of these materials ranges from about 40% to about 80% by weight of the total weight of the formulation.

[0352] According to some of the optional embodiments described herein, the formulation includes one or more monofunctional curable materials.

[0353] According to any of the embodiments described herein, one or more of the, or each, monofunctional curable materials is a hydrophilic material as defined herein, for example having Formula A1.

[0354] According to some embodiments, at least one of the monofunctional curable materials is a monofunctional (meth)acrylate, preferably a monofunctional acrylate having formula A1, where R1 is a carboxylate. In some of these embodiments, R' is a poly(alkylene glycol) as defined herein. One example of such a hydrophilic monofunctional acrylate is hexa(ethylene glycol) acrylate (6-PEA).

[0355] According to some embodiments, at least one of the monofunctional curable materials is a monofunctional (meth)acrylamide, preferably a monofunctional acrylate having formula A1, where R1 is an amide. According to some embodiments, at least one of the monofunctional curable materials is a monofunctional acrylamide. In some of these embodiments, Ra is a short chain alkyl having a length of 2-8, or 2-6, or 2-4 carbon atoms, terminated by a hydrophilic group as defined herein. One example of such a hydrophilic group is hydroxyalkyl, e.g., hydroxyethyl.

[0356] According to some of the embodiments described herein, one or more, or each, of the monofunctional curable material(s) is a water-miscible or water-soluble material as defined herein.

[0357] According to some of the optional embodiments described herein, the formulation includes a polyfunctional (eg, difunctional) aliphatic or cycloaliphatic (meth)acrylate.

[0358] According to some embodiments, the formulation comprises a difunctional aliphatic or cycloaliphatic (meth)acrylate.

[0359] According to some of the embodiments described herein, the formulation includes a multifunctional (eg, difunctional) aliphatic or cycloaliphatic acrylate.

[0360] According to some of the optional embodiments described herein, the formulation includes a difunctional aliphatic or cycloaliphatic acrylate, i.e., an aliphatic or cycloaliphatic diacrylate.

[0361] According to some of the embodiments of any of the embodiments described herein, the formulation includes a multifunctional (eg, difunctional) cycloaliphatic (meth)acrylate.

[0362] According to some of the embodiments of any of the embodiments described herein, the formulation includes a difunctional cycloaliphatic (meth)acrylate.

[0363] According to some of the embodiments described herein, the formulation includes a multifunctional cycloaliphatic acrylate.

[0364] According to some of the embodiments of any of the embodiments described herein, the formulation includes a difunctional cycloaliphatic acrylate, a cycloaliphatic diacrylate.

[0365] According to some of the optional embodiments described herein, the formulation includes a multifunctional (e.g., difunctional) cycloaliphatic (meth)acrylate characterized by a high Tg when cured, e.g., greater than 100° C.

[0366] According to some of the optional embodiments described herein, the formulation includes a difunctional cycloaliphatic (meth)acrylate characterized by a high Tg when cured, e.g., greater than 100°C.

[0367] According to some of the optional embodiments described herein, the formulation includes a difunctional cycloaliphatic acrylate or cycloaliphatic diacrylate characterized by a high Tg when cured, e.g., greater than 100°C.

[0368] According to some of the embodiments described herein, the cycloaliphatic diacrylate comprises a cycloaliphatic moiety having at least 6, 7, 8 or more carbon atoms.

[0369] According to some of the embodiments described herein, the cycloaliphatic diacrylate comprises an cycloaliphatic moiety that includes two, three or more fused rings.

[0370] According to some of the optional embodiments described herein, the multifunctional (meth)acrylates described herein in any of their respective embodiments are characterized in that when cured, they have a Tg in the range of 100-300° C., or 150-300° C., or 100-200° C., or 150-200° C., including any intermediate values ​​and subranges therebetween.

[0371] According to some of the optional embodiments of this aspect of the invention, the support material formulation includes a photoinitiator and, optionally, one or more of a dispersant, a polymerization inhibitor, etc., as described herein in any of the respective embodiments of the modeling material formulation.

[0372] According to some embodiments, the amount of photoinitiator ranges from 0.1% to 1% by weight of the total weight of the formulation.

[0373] [method:]

[0374] According to an aspect of some embodiments of the present invention there is provided a method for additive manufacturing of a three-dimensional object as described herein, the method of the present embodiment being usable for manufacturing a prosthetic tooth structure as defined herein.

[0375] The method is typically performed by sequentially forming a plurality of layers in a configuration pattern corresponding to the shape of the object, with the formation of at least some of the plurality of layers, or each of the plurality of layers, including dispensing a build material (uncured) that includes one or more modeling material formulations, and exposing the dispensed modeling material to curing conditions, preferably curing energy (e.g., radiation), thereby forming a cured modeling material, as described in more detail below.

[0376] In some exemplary embodiments of the invention, an object is fabricated by dispensing a build material (uncured) that includes two or more different modeling material formulations, for example as described below, in some of these embodiments, each modeling material formulation is dispensed from a different nozzle array belonging to the same or different dispensing head of an inkjet printing apparatus, as described herein.

[0377] In some embodiments, two or more such nozzle arrays ejecting different modeling material formulations are both located on the same print head (i.e., a multi-channel print head) of the AM device. In some embodiments, the nozzle arrays ejecting different modeling material formulations are located on separate print heads. For example, a first nozzle array ejecting a first modeling material formulation is located on a first print head and a second nozzle array ejecting a second modeling material formulation is located on a second print head.

[0378] In some embodiments, the nozzle array that ejects the modeling material formulation and the nozzle array that ejects the support material formulation are both located on the same print head, in some embodiments, the nozzle array that ejects the modeling material formulation and the nozzle array that ejects the support material formulation are located on separate print heads.

[0379] The modeling material formulations are optionally, but preferably, deposited in layers during the same pass of the print head. The modeling material formulations and / or combinations of formulations within a layer are selected according to the desired properties of the object, and as described in more detail below. Such a mode of operation is also referred to herein as "multi-material."

[0380] The term "digital material" as used herein and in the art refers to a combination of two or more materials at a microscopic scale or voxel level, where a printed area of ​​a particular material may be at the level of a few voxels or at the level of a block of voxels. Such digital materials may exhibit new properties that are influenced by the choice of material types and / or the ratio and relative spatial distribution of two or more materials.

[0381] In the exemplary digital material, the modeling material of each voxel or voxel block that results when hardened is independent of the modeling material of adjacent voxels or voxel blocks that results when hardened, such that each voxel or voxel block may yield a different model material, and new properties of the entire part are the result of a spatial combination of several different model materials at the voxel level.

[0382] The term "digital material blend" as used herein and in the art refers to the combination of two or more material blends at the pixel or voxel level, such that pixels or voxels of different material blends intersect with each other over an area. Such digital material blends may exhibit new properties that are influenced by the selection of material blend types and / or the ratios and relative spatial distribution of the two or more material blends.

[0383] As used herein, a "voxel" of a layer refers to a three-dimensional physical elemental volume within the layer that corresponds to a single pixel in a bitmap that describes the layer. The size of a voxel is approximately equal to the size of the area that would be formed by the build material if the build material were dispensed at the location corresponding to the respective pixel, flattened, and solidified.

[0384] Throughout this specification, whenever the phrase "at the voxel level" is used in the context of different materials and / or properties, it is meant to include differences between voxel blocks as well as differences between voxels or groups of small numbers of voxels. In a preferred embodiment, the properties of the whole part are the result of a spatial combination at the voxel block level of several different model materials.

[0385] In some of the optional embodiments of the present invention, once a layer has been jetted as described herein, exposure to curing conditions (e.g., curing energy) as described herein occurs. In some embodiments, the curable material is a photocurable material, preferably a UV curable material, and the curing conditions are such that the radiation source emits UV radiation.

[0386] In some of any of the embodiments described herein, the UV illumination is from an LED light source as described herein.

[0387] In some of the embodiments of any of the embodiments described herein, the curing conditions include electromagnetic radiation, wherein the electromagnetic radiation is from an LED light source.

[0388] In some of the embodiments described herein, the curing conditions include UV radiation.

[0389] In some embodiments where the build material also includes a support material formulation(s), the method proceeds with removing the hardened support material (e.g., thereby exposing adjacent hardened modeling material). This can be done by mechanical and / or chemical means, as will be appreciated by those skilled in the art. As described herein, a portion of the support material may optionally remain upon removal, for example, within the hardened mixed layer.

[0390] In some embodiments, removal of the hardened support material exposes a hardened intermixed layer that includes a hardened mixture of the support material and the modeling material formulation. Such hardened mixture at the surface of the object can optionally have a relatively non-reflective appearance, also referred to herein as "matte," while a surface that does not have such a hardened mixture (e.g., where no support material formulation was applied) is described as "glossy" in comparison.

[0391] In some of any of the embodiments described herein, if a support material is included in the building material, the method further includes exposing the hardened modeling material to post-processing conditions either before or after (preferably after) removal of the support material.

[0392] According to any of the embodiments described herein, one or more, or all, of the ejected modeling material formulations are modeling material formulations described herein in any of the respective embodiments and any combination thereof.

[0393] According to some of the embodiments described herein, the dispensing is the dispensing of two or more modeling material formulations, each independently a formulation described herein in any of the respective embodiments and any combination thereof, In some of these embodiments, the dispensing is the dispensing of a digital material described herein.

[0394] In an exemplary embodiment, the two or more formulations differ from one another by the presence and / or type of colorant, allowing for the production of a single object (e.g., a unitary denture structure as described herein) featuring multiple colors and hues.

[0395] According to some of the embodiments described herein, the ejection is of a support material formulation, for example, of a support material formulation described herein in any of the respective embodiments and any combination thereof.

[0396] According to some of the optional embodiments described herein, once the support material is removed, the object is subjected to a post-curing process, i.e., a post-treatment.

[0397] In an exemplary post-treatment procedure, the printed object is subjected to support material removal (e.g., using a water jet), then sequentially treated with a solution of strong base (e.g., sodium hydroxide) (e.g., using a water jet), with glycerol (preferably with heating and UV irradiation for 2-4 hours), and with alcohol (e.g., isopropyl alcohol). The object may be rinsed with tap water between contact with each of these components. The object is then overdried or air-dried for at least 2 hours.

[0398] According to some of the optional embodiments described herein, the additive manufacturing is 3D inkjet printing.

[0399] According to some of the optional embodiments described herein, the denture structure is selected from a denture base, a single artificial tooth, a plurality of artificial teeth, and a unitary structure of a denture base and artificial teeth.

[0400] According to some of the optional embodiments described herein, the denture structure is a unitary structure of a denture base and artificial teeth.

[0401] [object:]

[0402] According to an aspect of some embodiments of the present invention there is provided a denture structure as described herein, obtained by additive manufacturing as described herein.

[0403] According to some embodiments, the denture structure is a unitary structure of denture base and artificial teeth.

[0404] According to an aspect of some embodiments of the present invention there is provided a three dimensional printed object that is an integrated structure of a denture base and artificial teeth.

[0405] According to some of the optional embodiments described herein, the denture structures are characterized by mechanical and physical properties in accordance with the requirements of ISO 20795-1 and ISO 10477, and biocompatibility in accordance with the requirements of ISO 10993-1.

[0406] [system:]

[0407] A representative, non-limiting example of a system 110 suitable for AM of an object 112, according to some embodiments of the present invention, is shown in Figure 1A. The system 110 includes an additive manufacturing device 114 having a dispensing unit 16 that includes multiple print heads. Each head preferably includes an array of one or more nozzles 122, typically attached to an orifice plate 121, through which a liquid build material formulation 124 is dispensed, as shown in Figures 2A-2C described below.

[0408] Preferably, but not necessarily, the device 114 is a 3D printing device, in which case the print head is a print head and the build material formulation is dispensed via inkjet technology. This is not necessarily the case, as in some applications the additive manufacturing device may not need to use 3D printing technology. Representative examples of additive manufacturing devices contemplated in accordance with various exemplary embodiments of the present invention include, but are not limited to, fused deposition modeling devices and molten material formulation deposition devices.

[0409] Each print head is optionally, but preferably, supplied with material via one or more build material formulation reservoirs, which may optionally include a temperature control unit (e.g., temperature sensor and / or heating device) and a material formulation level sensor. To eject the build material formulation, a voltage signal is applied to the print head, which selectively deposits droplets of the material formulation through the print head nozzles, similar to, for example, piezoelectric inkjet printing technology. Another example is a thermal inkjet print head. This type of head has a heater element in thermal contact with the build material formulation, and the voltage signal activates the heater element to heat the build material formulation and form a gas bubble therein. The gas bubble creates pressure in the build material formulation, causing a droplet of the build material formulation to be ejected from the nozzle. Piezoelectric and thermal print heads are known to those skilled in the art of solid freeform fabrication. For either type of inkjet print head, the ejection speed of the head depends on the number of nozzles, the type of nozzle, and the applied voltage signal speed (frequency).

[0410] Optionally, the total number of ejection nozzles or nozzle arrays is selected such that half of the ejection nozzles are designated to eject the support material formulation and half of the ejection nozzles are designated to eject 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 the representative example of FIG. 1A, four print heads 16a, 16b, 16c, and 16d are shown. Each head 16a, 16b, 16c, and 16d has a nozzle array. In this example, heads 16a and 16b may be designated for modeling material formulation(s) and heads 16c and 16d may be designated 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 alternative embodiments, for example, heads 16c and 16d can be combined into a single head having two nozzle arrays for depositing the support material formulation. In further alternative embodiments, any one or more print heads may have two or more nozzle arrays for depositing two or more material formulations, for example two nozzle arrays for depositing two different modeling material formulations, or two nozzle arrays for depositing one modeling material formulation and one support material formulation, with each formulation deposited through a different array or different number of nozzles.

[0411] However, this is not intended to limit the scope of the invention, and 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 be different. Typically, the number of nozzle arrays discharging modeling material formulations, the number of nozzle arrays discharging support material formulations, and the number of nozzles in each array are selected to provide a predetermined ratio a between the maximum discharging speed of the support material formulation and the maximum discharging speed of the modeling material formulation. The value of the predetermined ratio a is preferably selected such that in each layer formed, the height of the modeling material formulation is equal to the height of the support material formulation. A typical value of a is about 0.6 to about 1.5.

[0412] As used herein, the term "about" refers to ±10%.

[0413] For example, when a=1, the overall dispensing rate of the support material formulation is typically the same as the overall dispensing rate of the modeling material formulation when all nozzle arrays are operational.

[0414] The apparatus 114 may, for example, comprise M modeling heads, each having m arrays of p nozzles, and S support heads, each having s arrays of q nozzles, such that M×m×p=S×s×q. Each of the M×m modeling arrays and the S×s support arrays may be manufactured as separate physical units, and may be assembled and disassembled from the group of arrays. In this embodiment, each such array may optionally, but preferably, comprise its own temperature control unit and material formulation level sensor, and receive an individually controlled voltage for its operation.

[0415] The apparatus 114 can further include a solidification device 324, which can include any device configured to emit light, heat, etc., that can harden the deposited material formulation. For example, the solidification device 324 can include one or more radiation sources, which can be, for example, ultraviolet, visible, or infrared lamps, or other electromagnetic radiation sources, or electron beam sources, depending on the modeling material formulation used. In some embodiments of the invention, the solidification device 324 serves to cure or solidify the modeling material formulation.

[0416] In addition to the solidification device 324, the device 114 optionally, but preferably, includes an additional radiation source 328 for solvent evaporation. The radiation source 328 optionally, but preferably, generates infrared light. In various exemplary embodiments of the invention, the solidification device 324 comprises a radiation source that generates ultraviolet light and the radiation source 328 generates infrared light.

[0417] In some embodiments of the invention, the device 114 includes a cooling system 134, such as one or more fans.

[0418] The print head and the radiation source are preferably mounted in a frame or block 128, which is preferably operable to move back and forth over a tray 360, which serves as a working surface. In some embodiments of the invention, the radiation source is mounted in the block and configured to follow the print head and at least partially cure or solidify the material formulation just dispensed by the print head. The tray 360 is arranged horizontally. According to common convention, an XYZ Cartesian coordinate system (i.e., a 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), typically downwards. In various exemplary embodiments of the invention, the device 114 further comprises one or more leveling devices 132, such as, for example, rollers 326. The leveling devices 326 serve to regulate, level and / or establish the thickness of the newly formed layer before forming successive layers thereon. The leveling devices 326 preferably comprise a waste collection device 136 for collecting excess material formulation generated during leveling. The waste collector 136 may include any mechanism for delivering a material mix to a waste tank or waste cartridge.

[0419] In use, the print heads of the units 16 move in a scanning direction, referred to herein as the X-direction, and selectively dispense build material formulations in a predetermined configuration as they pass over the tray 360. The build material formulations typically include one or more support material formulations and one or more modeling material formulations. The pass of the print heads of the units 16 is followed by curing of the modeling material formulations by the radiation source 126. An additional dispense of the build material formulation may be made according to a predetermined configuration during a reverse pass of the head back to the starting point of the just deposited layer. The layers thus formed during the forward and / or reverse passes of the print heads may be maintained by a leveling device 326, which preferably follows the path of the forward and / or reverse movement of the print heads. When the print heads return to their starting points along the X-direction, they may move to another position along an indexing direction, referred to herein as the Y-direction, and continue to build the same layer by a reciprocating movement along the X-direction. Alternatively, the print head may move in the Y direction between forward and reverse moves, or after two or more forward-reverse moves. The series of scans performed by the print head to complete a single layer is referred to herein as a single scan cycle.

[0420] Once a layer is completed, 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 to build up the three-dimensional object 112 layer by layer.

[0421] In another embodiment, the tray 360 may be displaced in the Z direction within the layer between forward and reverse passes of the print head of unit 16. Such Z displacement is performed to allow the leveling device to contact the surface in one direction and prevent contact in the other direction.

[0422] System 110 optionally, but preferably, includes a build material formulation supply system 330 that includes build material formulation containers or cartridges and supplies a plurality of build material formulations to manufacturing device 114 .

[0423] The control unit 152 controls the manufacturing equipment 114, and optionally, but preferably also the supply system 330. The control unit 152 typically includes electronic circuitry configured to perform control operations. The control unit 152 is preferably in communication with a data processor 154, which transmits digital data regarding manufacturing instructions based on computer object data, such as CAD configurations represented on a computer-readable medium in a format such as the Standard Tessellation Language (STL) format. Typically, the control unit 152 controls the voltage applied to each print head or each nozzle array and the temperature of the build material formulation at each print head or each nozzle array.

[0424] Once the manufacturing data is loaded into the control unit 152, the control unit 152 can operate without user intervention. In some embodiments, the control unit 152 receives additional input from an operator, for example, using the data processor 154 or using a user interface 116 in communication with the unit 152. The user interface 116 can be of any type known in the art, such as, but not limited to, a keyboard, a touch screen, etc. For example, the control unit 152 can receive one or more build material formulation types and / or attributes as additional input. The attributes can be, but are not limited to, color, characteristic distortion and / or transition temperature, viscosity, electrical properties, magnetic properties, etc. Other attributes and groups of attributes are also contemplated.

[0425] Another representative, non-limiting example of a system 10 suitable for AM of an object according to some embodiments of the present invention is shown in Figures 1B-1D, which show a top view (Figure 1B), a side view (Figure 1C), and an isometric view (Figure 1D) of the system 10.

[0426] In this embodiment, system 10 includes a tray 12 and a plurality of inkjet print heads 16, each having one or more nozzle arrays with one or more separate nozzles. Material used for 3D printing is supplied to heads 16 by a build material supply system 42. Tray 12 may have the shape of a disk or may be annular. Non-circular shapes are contemplated, as long as they are rotatable about a vertical axis.

[0427] The tray 12 and head 16 are optionally, but preferably, mounted to allow relative rotational movement between the tray 12 and head 16. This can be accomplished by (i) configuring the tray 12 to rotate about a vertical axis 14 relative to the head 16, (ii) configuring the head 16 to rotate about a vertical axis 14 relative to the tray 12, or (iii) configuring both the tray 12 and the head 16 to rotate at different rotational speeds (e.g., rotation in opposite directions) about the vertical axis 14. Some embodiments of the system 10 below are described with particular emphasis on configuration (i), in which the tray is a rotating tray configured to rotate about a vertical axis 14 relative to the head 16, but it should be understood that configurations (ii) and (iii) of the system 10 are also contemplated by the present application. Any of the embodiments of the system 10 described herein can be adjusted to be applicable to either configuration (ii) or configuration (iii), and one of ordinary skill in the art would know how to make such adjustments given the details provided herein.

[0428] In the following description, the direction parallel to the tray 12 and pointing outward from the axis 14 will be referred to as the radial direction r, the direction parallel to the tray 12 and perpendicular to the radial direction r will be referred to herein as the azimuthal direction φ, and the direction perpendicular to the tray 12 will be referred to herein as the vertical direction z.

[0429] The radial direction r in system 10 defines an index direction y in system 110, and the azimuthal direction φ defines a scan direction x in system 110. Thus, in this specification, the radial directions are interchangeably referred to as index directions, and the azimuthal directions are interchangeably referred to as scan directions.

[0430] As used herein, the term "radial position" refers to a position on or above tray 12 that is a particular distance from axis 14. When the term is used in relation to a print head, the term refers to a position of the head that is a particular distance from axis 14. When the term is used in relation to a point on tray 12, the term corresponds to any point belonging to a locus of points that forms a circle whose radius is a particular distance from axis 14 and whose center is on axis 14.

[0431] As used herein, the term "azimuth position" refers to a position on or above tray 12 that is at a particular azimuth angle relative to a given reference point. A radial position thus refers to any point belonging to a locus of points that make a line that forms a particular azimuth angle relative to a reference point.

[0432] As used herein, the term "vertical position" refers to a position on a plane that intersects the vertical axis 14 at a particular point.

[0433] The tray 12 serves as a build platform for 3D printing. The working area on which one or more objects are printed is usually, but not necessarily, smaller than the total area of ​​the tray 12. In some embodiments of the invention, the working area is annular. The working area is indicated by the reference numeral 26. In some embodiments of the invention, the tray 12 rotates continuously in the same direction throughout the formation of the object, and in some embodiments of the invention, the tray 12 reverses its direction of rotation (e.g., to oscillate) at least once during the formation of the object. The tray 12 is optionally, but preferably, removable. Removal of the tray 12 can be performed for maintenance of the system 10, or to replace the tray before printing a new object, as desired. In some embodiments of the invention, the system 10 includes one or more different replacement trays (e.g., a kit of replacement trays), with two or more trays designated for different types of objects (e.g., different weights), different modes of operation (e.g., different rotation speeds), etc. Replacement of the tray 12 can be performed manually or automatically, as desired. When automated exchange is used, the system 10 includes a tray exchanger 36 configured to remove the tray 12 from its position beneath the head 16 and replace it with a replacement tray (not shown). In the representative diagram of Figure 1B, the tray exchanger 36 is shown as a drive 38 having a movable arm 40 configured to pull the tray 12, although other types of tray exchangers are contemplated.

[0434] Exemplary embodiments of print head 16 are illustrated in Figures 2A-2C. These embodiments may be employed in any of the AM systems described above, including, but not limited to, system 110 and system 10.

[0435] 2A-2B show print heads 16 with one nozzle array 22 (FIG. 2A) and two nozzle arrays 22 (FIG. 2B). The nozzles in the arrays are preferably arranged linearly along a straight line. In embodiments where a particular print head has two or more linear nozzle arrays, the nozzle arrays may optionally be parallel to one another, preferably parallel to one another. When a print head has two or more nozzle arrays (e.g., FIG. 2B), all arrays in the head may be supplied with the same build material formulation, or at least two arrays in the same head may be supplied with different build material formulations.

[0436] If a system similar to system 110 is employed, all print heads 16 are optionally, but preferably, oriented along an index direction with their positions along the scan direction offset from one another.

[0437] When a system similar to system 10 is employed, all print heads 16 are optionally, but preferably, oriented radially (parallel to the radial direction) with their azimuthal positions offset from one another. Thus, in these embodiments, the nozzle arrays of the different print heads are not parallel to one another, but rather at an angle to one another, the angle being approximately equal to the azimuthal offset between the respective heads. For example, one head may be oriented radially and located at an azimuthal position φ1, while another head may be oriented radially and located at an azimuthal position φ2. In this example, the azimuthal offset between the two heads is φ1-φ2, and the angle between the linear nozzle arrays of the two heads is also φ1-φ2.

[0438] In some embodiments, two or more print heads can be assembled into a block of print heads, where the print heads in the block are generally parallel to one another. A block including several inkjet print heads 16a, 16b, 16c is shown in FIG. 2C.

[0439] In some embodiments, the system 10 includes a stabilizing structure 30 positioned below the head 16, such that the tray 12 is between the stabilizing structure 30 and the head 16. The stabilizing structure 30 can serve to prevent or reduce vibrations of the tray 12 that may occur while the inkjet print head 16 is in operation. In configurations in which the print head 16 rotates about axis 14, the stabilizing structure 30 also preferably rotates so that the stabilizing structure 30 is always directly below the head 16 (with the tray 12 between the head 16 and the tray 12).

[0440] The tray 12 and / or print head 16 are optionally configured to move, preferably parallel to the vertical axis 14, along a vertical direction z, to vary the vertical distance between the tray 12 and the print head 16. In configurations in which the vertical distance is varied by moving the tray 12 along the vertical direction, the stabilizing structure 30 also preferably moves vertically with the tray 12. In configurations in which the vertical position of the tray 12 remains fixed and the vertical distance is changed by the head 16 along the vertical direction, the stabilizing structure 30 is also maintained in a fixed vertical position.

[0441] Vertical motion can be established by vertical drive 28. Once a layer is completed, the vertical distance between tray 12 and head 16 can be increased (e.g., tray 12 is lowered relative to head 16) by a predetermined vertical interval depending on the desired thickness of the next layer to be printed. This procedure is repeated to build the three-dimensional object layer by layer.

[0442] The operation of inkjet print head 16, and optionally, and preferably, the operation of one or more other components of system 10, such as tray 12, is controlled by a controller 20. The controller may include electronic circuitry and a non-volatile storage medium readable by the circuitry that stores program instructions that, when read by the circuitry, cause the circuitry to perform control operations, as described in more detail below.

[0443] The controller 20 can also communicate with a host computer 24, which transmits digital data related to manufacturing instructions based on the computer object data. The computer object data is in the form of, for example, 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), or any other format suitable for computer-aided design (CAD). The object data format is usually structured according to a Cartesian coordinate system. In these cases, the computer 24 preferably performs a procedure to convert the coordinates of each slice in the computer object data from a Cartesian coordinate system to a polar coordinate system. The computer 24 optionally transmits manufacturing instructions using the converted coordinate system. Alternatively, the computer 24 can transmit manufacturing instructions using the original coordinate system provided by the computer object data, in which case the conversion of coordinates is performed by the circuitry of the controller 20.

[0444] The transformation of coordinates allows 3D printing on a rotating tray. In a non-rotating system with a stationary tray, the print head typically moves back and forth along a straight line above the stationary tray. In such a system, if the head has a uniform discharge speed, the printing resolution is the same at any point on the tray. In the system 10, unlike a non-rotating system, not all nozzles of the head point cover the same distance on the tray 12 at the same time. The transformation of coordinates is optionally, but preferably, performed to ensure equal amounts of excess material mix at different radial positions. A representative example of the transformation of coordinates according to some embodiments of the present invention is shown in Figures 3A-3B, which show three slices of an object, each slice corresponding to a manufacturing instruction for a different layer of the object. Figure 3A shows the slices in a Cartesian coordinate system, and Figure 3B shows the same slices after applying a coordinate transformation procedure to each slice.

[0445] Typically, controller 20 controls the voltages applied to each component of system 10 based on manufacturing instructions, and based on stored program instructions as described below.

[0446] Typically, a controller 20 controls the print head 16 while the tray 12 rotates to eject droplets of the build material formulation layer by layer onto the tray 12 to print the three-dimensional object.

[0447] System 10 optionally, but preferably, includes one or more radiation sources 18, which may be, for example, ultraviolet lamps, visible light lamps, infrared lamps, or other electromagnetic radiation sources, or electron beam sources, depending on the modeling material formulation used. Radiation sources may include any type of radiation emitting device, including, but not limited to, light emitting diodes (LEDs), digital light processing (DLP) systems, resistive lamps, and the like. Radiation sources 18 serve to cure or solidify the modeling material formulation. In various exemplary embodiments of the invention, the operation of radiation sources 18 is controlled by a controller 20, which may activate and deactivate radiation sources 18, and may optionally also control the amount of radiation generated by radiation sources 18.

[0448] In some embodiments of the invention, the system 10 further comprises one or more leveling devices 32, which can be manufactured as rollers or blades. The leveling devices 32 serve to prepare the newly formed layer before forming a successive layer thereon. In some embodiments, the leveling devices 32 have the shape of a conical roller arranged with its axis of symmetry 34 inclined with respect to the surface of the tray 12 and with its surface parallel to the surface of the tray. This embodiment is shown in a side view of the system 10 (FIG. 1C).

[0449] The conical roller may have the shape of a cone or a frustum of a cone.

[0450] The opening angle of the conical roller is preferably selected such that the ratio between the radius of the cone at any position along its axis 34 and the distance between that position and the axis 14 is constant. This embodiment allows the roller 32 to efficiently flatten the layer, since any point p on the surface of the roller while it rotates has a linear velocity that is proportional (e.g., the same) as the linear velocity of the tray at a point located directly below point p. In some embodiments, the roller has the shape of a truncated cone with height h and radius R1 at its closest distance from the axis 14 and radius R2 at its furthest distance from the axis 14. The parameters h, R1, and R2 satisfy the relationship R1 / R2=(Rh) / h, where R is the furthest distance of the roller from the axis 14 (e.g., R can be the radius of the tray 12).

[0451] The operation of the leveling device 32 is optionally, but preferably, controlled by the controller 20. The controller can activate and deactivate the leveling device 32 and, optionally, control its position along a vertical direction (parallel to the axis 14) and / or along a radial direction (parallel to the tray 12, toward or away from the axis 14).

[0452] In some embodiments of the invention, the print head 16 is configured to move back and forth 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 less than the radial width of a working area 26 on the tray 12. The movement of the head 16 along the radial direction is optionally, but preferably, controlled by the controller 20.

[0453] As used herein, the term "about" refers to ±10% or ±5%.

[0454] The terms "comprises," "comprising," "includes," "including," "having" and their conjugations mean "including, but not limited to."

[0455] The term "consisting of" means "including and limited to."

[0456] The term "consisting essentially of" means that a composition, method, or structure may include additional components, steps, and / or moieties, but only if the additional components, steps, and / or moieties do not materially alter the basic and novel characteristics of the claimed composition, method, or structure.

[0457] As used herein, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. For example, the term "a compound" or "at least one compound" can include a plurality of compounds, including mixtures thereof.

[0458] Throughout this application, various embodiments of the invention may be presented in a range format. It should be understood that the description in range format is merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the invention. Thus, the description of a range should be considered to have specifically disclosed all possible subranges and individual numerical values ​​within that range. For example, description of a range such as 1-6 should be considered to have specifically disclosed subranges such as 1-3, 1-4, 1-5, 2-4, 2-6, 3-6, etc., as well as individual numbers within that range, for example, 1, 2, 3, 4, 5, and 6. This applies regardless of the breadth of the range.

[0459] Whenever a numerical range is given herein, it is meant to include any recited numbers (fractional or integer) within the given range. The phrases "ranging / ranges between" a first designated number and a second designated number, and "ranging / ranges from" a first designated number "to" a second designated number, are used interchangeably herein and are meant to include the first and second designated numbers and all fractional and integer numbers therebetween.

[0460] As used herein, the terms "method" and "process" are used interchangeably and refer to ways, means, techniques, and procedures for accomplishing a given task, including, but not limited to, those methods, means, techniques, and procedures known to or readily developed from known methods, means, techniques, and procedures by those skilled in the art of chemistry, pharmacology, biology, biochemistry, and medicine.

[0461] Throughout this specification, whenever the expressions "weight percent" or "wt. %" or "% wt" are presented in the context of an embodiment of a formulation (e.g., a modeling formulation), they refer to the weight percent relative to the total weight of the respective uncured formulation.

[0462] Throughout this specification, acrylic materials are used collectively to refer to materials characterized by one or more acrylate, methacrylate, acrylamide, and / or methacrylamide groups.

[0463] Similarly, acrylic groups are used collectively to refer to curable groups that are acrylate groups, methacrylate groups, acrylamide groups, and / or methacrylamide groups, preferably acrylate groups, or methacrylate groups (also referred to herein as (meth)acrylate groups).

[0464] Throughout this specification, the term "(meth)acrylic" encompasses acrylic and methacrylic materials.

[0465] Throughout this specification, the term "linker" or "linking group" refers to a group that links two or more moieties or groups in a compound. A linker is usually derived from a bi- or tri-functional compound and can be considered as a bi- or tri-radical moiety that is linked to two or three other moieties through two or three of its atoms, respectively.

[0466] Exemplary linking moieties, as defined herein, include a hydrocarbon moiety or chain, optionally interrupted by one or more heteroatoms, and / or, when defined as a linking group, include any of the chemical groups exemplified below.

[0467] When a chemical group is referred to herein as an "end group", it is to be understood as a substituent that is connected via one of its atoms to another group.

[0468] Throughout this specification, the term "hydrocarbon" refers generally to a chemical group composed primarily of carbon and hydrogen atoms. The hydrocarbon may be composed of alkyl, alkene, alkyne, aryl and / or cycloalkyl, each of which may be substituted or unsubstituted and may be interrupted by one or more heteroatoms. The number of carbon atoms may range from 2 to 30, and is preferably less, for example 1 to 10, or 1 to 6, or 1 to 4. The hydrocarbon may be a linking group or a terminal group.

[0469] Bisphenol A is an example of a hydrocarbon that consists of two aryl groups and one alkyl group. Dimethylencyclohexane is an example of a hydrocarbon that consists of two alkyl groups and one cycloalkyl group.

[0470] As used herein, the term "amine" refers to both the -NR'R'' and -NR'- groups, where R' and R'' are each independently hydrogen, alkyl, cycloalkyl, or aryl, as these terms are defined below.

[0471] Thus, the amine group can be a primary amine where R' and R'' are both hydrogen, a secondary amine where R' is hydrogen and R'' is alkyl, cycloalkyl, or aryl, or a tertiary amine where each of R' and R'' is independently alkyl, cycloalkyl, or aryl.

[0472] Alternatively, R' and R'' can each independently be hydroxyalkyl, trihaloalkyl, cycloalkyl, alkenyl, alkynyl, aryl, heteroaryl, alicyclic heterocycle, amine, halide, 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.

[0473] The term "amine" is used herein to represent the -NR'R'' group when the amine is a terminal group and the -NR'- group when the amine is a linking group or part of a linkage or moiety, as defined herein below.

[0474] The term "alkyl" refers to saturated aliphatic hydrocarbons, including straight-chain and branched-chain groups. Preferably, the alkyl group has 1 to 30, or 1 to 20 carbon atoms. Whenever a numerical range is stated herein, e.g., "1 to 20," it means that the group, in this case the alkyl group, can contain up to 20 carbon atoms, such as 1 carbon atom, 2 carbon atoms, 3 carbon atoms, etc. The alkyl group can be substituted or unsubstituted. A substituted alkyl can have one or more substituents, each of which can independently be, for example, hydroxyalkyl, trihaloalkyl, cycloalkyl, alkenyl, alkynyl, aryl, heteroaryl, alicyclic heterocycle, amine, halide, 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.

[0475] An alkyl group, as that term is defined herein above, can be a terminal group attached to a single adjacent atom, or it can be a linking group, as that term is defined herein above, linking two or more moieties through at least two carbons in the chain. When an alkyl is a linking group, it is also referred to herein as an "alkylene" or an "alkylene chain."

[0476] Alkenes and alkynes as used herein are alkyl, as defined herein, containing one or more double or triple bonds, respectively.

[0477] The term "cycloalkyl" refers to an all-carbon monocyclic or fused ring (i.e., rings that share adjacent pairs of carbon atoms) group in which one or more of the rings does not have a completely conjugated pi-electron system. Examples include, but are not limited to, cyclohexane, adamantine, norbornyl, isobornyl, and the like. Cycloalkyl groups can be substituted or unsubstituted. Substituted cycloalkyls may have one or more substituents, each of which may be, independently, for example, hydroxyalkyl, trihaloalkyl, cycloalkyl, alkenyl, alkynyl, aryl, heteroaryl, alicyclic heterocycle, amine, halide, 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. Cycloalkyl groups may be terminal groups attached to a single adjacent atom, as that term is defined herein above, or may be linking groups, as that term is defined herein above, linking two or more moieties at two or more positions thereof.

[0478] The term "heteroalicyclic" refers to a monocyclic or fused ring group having one or more atoms in the ring, such as nitrogen, oxygen, and sulfur. The ring may also have one or more double bonds, provided that the ring does not have a completely conjugated pi-electron system. Representative examples are piperidine, piperazine, tetrahydrofuran, tetrahydropyran, morpholino, oxalidine, and the like.

[0479] The heteroalicyclic group may be substituted or unsubstituted. Substituted heteroalicyclic groups may have one or more substituents, each of which may be, independently, for example, hydroxyalkyl, trihaloalkyl, cycloalkyl, alkenyl, alkynyl, aryl, heteroaryl, heteroalicyclic, amine, halide, 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. An alicyclic heterocyclic group, as that term is defined hereinabove, can be a terminal group attached to a single adjacent atom, or it can be a linking group, as that term is defined hereinabove, linking two or more moieties at two or more of its positions.

[0480] The term "aryl" refers to an all-carbon monocyclic or fused-ring polycyclic (i.e., rings sharing adjacent pairs of carbon atoms) group having a completely conjugated pi-electron system. The aryl group may be substituted or unsubstituted. A substituted aryl may have one or more substituents, each of which may be independently, for example, hydroxyalkyl, trihaloalkyl, cycloalkyl, alkenyl, alkynyl, aryl, heteroaryl, alicyclic heterocycle, amine, halide, 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, as that term is defined hereinabove, can be a terminal group attached to a single adjacent atom, or it can be a linking group, as that term is defined hereinabove, linking two or more moieties at two or more of its positions.

[0481] The term "heteroaryl" refers to a monocyclic or fused ring (i.e., rings that share adjacent pairs of atoms) group having one or more atoms, such as nitrogen, oxygen, and sulfur, in the ring and further having a completely conjugated pi-electron system. Examples of heteroaryl groups include, but are not limited to, pyrrole, furan, thiophene, imidazole, oxazole, thiazole, pyrazole, pyridine, pyrimidine, quinoline, isoquinoline, and purine. Heteroaryl groups can be substituted or unsubstituted. Substituted heteroaryl may have one or more substituents, each of which may be independently, for example, hydroxyalkyl, trihaloalkyl, cycloalkyl, alkenyl, alkynyl, aryl, heteroaryl, alicyclic heterocycle, amine, halide, 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. Heteroaryl groups may be terminal groups that are attached to a single adjacent atom, as that term is defined herein above, or may be linking groups that link two or more moieties at two or more positions, as that term is defined herein above. Representative examples are pyridine, pyrrole, oxazole, indole, purine, and the like.

[0482] The terms "halide" and "halo" refer to fluorine, chlorine, bromine, or iodine.

[0483] The term "haloalkyl" refers to an alkyl group, as defined above, which is further substituted with one or more halide groups.

[0484] The term "sulfate" refers to an -OS(=O)2-OR' terminal group, as that term is defined hereinabove, or an -OS(=O)2-O- linking group, as that term is defined hereinabove, where R' is as defined hereinabove.

[0485] The term "thiosulfate" refers to an -OS(=S)(=O)-OR' terminal group, as that term is defined hereinabove, or an -OS(=S)(=O)-O- linking group, where R' is as defined hereinabove.

[0486] The term "sulfite", as that term is defined hereinabove, refers to an -OS(=O)-O-R' terminal group, or an -OS(=O)-O- linking group, where R' is as defined hereinabove.

[0487] The term "thiosulfite", as that term is defined hereinabove, refers to an -OS(=S)-O-R' terminal group, or an -OS(=S)-O- linking group, where R' is as defined hereinabove.

[0488] The term "sulfinate," as that term is defined hereinabove, refers to an -S(=O)-OR' terminal group, or an -S(=O)-O- linking group, where R' is as defined hereinabove.

[0489] The terms "sulfoxide" or "sulfinyl" as that term is defined hereinabove refer to an -S(=O)R' terminal group, or an -S(=O)- linking group, where R' is as defined hereinabove.

[0490] The term "sulfonate", as that term is defined herein above, refers to an -S(=O)2-R' terminal group, or an -S(=O)2- linking group, where R' is as defined herein.

[0491] The term "S-sulfonamide," as that term is defined herein above, refers to an -S(=O)2-NR'R'' terminal group, or an -S(=O)2-NR'- linking group, where R' and R'' are as defined herein.

[0492] The term "N-sulfonamide," as that term is defined herein above, refers to an R'S(=O)2-NR''- terminal group, or an -S(=O)2-NR'- linking group, where R' and R'' are as defined herein.

[0493] The term "disulfide", as that term is defined herein above, refers to an -S-SR' end group, or an -SS- linking group, where R' is as defined herein.

[0494] The term "phosphonate," as that term is defined hereinabove, refers to a -P(=O)(OR')(OR'') terminal group, or a -P(=O)(OR')(O)- linking group, where R' and R'' are as defined herein.

[0495] The term "thiophosphonate," as that term is defined hereinabove, refers to a -P(=S)(OR')(OR'') terminal group, or a -P(=S)(OR')(O)- linking group, where R' and R'' are as defined herein.

[0496] The term "phosphinyl," as that term is defined hereinabove, refers to a -PR'R'' terminal group, or a -PR'- linking group, where R' and R'' are as defined hereinabove.

[0497] The term "phosphine oxide", as that term is defined herein above, refers to a -P(=O)(R')(R'') terminal group, or a -P(=O)(R')- linking group, where R' and R'' are as defined herein.

[0498] The term "phosphine sulfide," as that term is defined herein above, refers to a -P(=S)(R')(R'') terminal group, or a -P(=S)(R')- linking group, where R' and R'' are as defined herein.

[0499] The term "phosphite", as that term is defined herein above, refers to an -O-PR'(=O)(OR'') end group, or an -O-PH(=O)(O)- linking group, where R' and R'' are as defined herein.

[0500] The term "carbonyl" or "carbonate" as used herein, as that term is defined herein above, refers to a -C(=O)-R' terminal group, or a -C(=O)- linking group, where R' is as defined herein.

[0501] The term "thiocarbonyl" as used herein, as that term is defined herein above, refers to a -C(=S)-R' terminal group, or a -C(=S)- linking group, where R' is as defined herein.

[0502] The term "oxo" as used herein represents a (=O) group, in which the oxygen atom is connected to the atom (eg, carbon atom) at the indicated position by a double bond.

[0503] The term "thiooxo" as used herein represents a (=S) group in which the sulfur atom is connected to the atom (eg, carbon atom) at the indicated position by a double bond.

[0504] The term "oxime" refers to the =N-OH terminal group, or the =NO- linking group, as that term is defined hereinabove.

[0505] The term "hydroxyl" refers to the group --OH.

[0506] The term "alkoxy" refers to both -O-alkyl and -O-cycloalkyl groups, as defined herein. The term alkoxide refers to -R'O - group, where R' is as defined herein.

[0507] The term "aryloxy" refers to both an --O-aryl and an --O-heteroaryl group, as defined herein.

[0508] The term "thiohydroxy" or "thiol" refers to the -SH group. The term "thiolate" refers to the -S - Represents a group.

[0509] The term "thioalkoxy" refers to both an --S-alkyl group, and an --S-cycloalkyl group, as defined herein.

[0510] The term "thioaryloxy" refers to both an --S-aryl and an --S-heteroaryl group, as defined herein.

[0511] "Hydroxyalkyl," also referred to herein as "alcohol," refers to an alkyl, as defined herein, substituted with a hydroxy group.

[0512] The term "cyano" refers to the group -C≡N.

[0513] The term "isocyanate" refers to the group --N.dbd.C.dbd.O.

[0514] The term "isothiocyanate" refers to the group --N.dbd.C.dbd.S.

[0515] The term "nitro" refers to the group --NO.sub.2.

[0516] The term "acyl halide" refers to the group --(C.dbd.O)R'''' where R'''' is a halide as defined hereinabove.

[0517] The terms "azo" or "diazo", as that term is defined hereinabove, refer to an -N=NR' terminal group, or an -N=N- linking group, where R' is as defined hereinabove.

[0518] The term "peroxo", as that term is defined hereinabove, refers to an -O-OR' terminal group, or an -OO- linking group, where R' is as defined hereinabove.

[0519] As used herein, the term "carboxylate" includes C-carboxylates and O-carboxylates.

[0520] The term "C-carboxylate" as that term is defined herein above refers to a -C(=O)-OR' terminal group, or a -C(=O)-O- linking group, where R' is as defined herein.

[0521] The term "O-carboxylate," as that term is defined herein above, refers to an -OC(=O)R' terminal group, or an -OC(=O)- linking group, where R' is as defined herein.

[0522] Carboxylate can be linear or cyclic. When cyclic, R' and carbon atom are linked together to form a ring in C-carboxylate, the group is also called lactone. Alternatively, R' and O are linked together to form a ring in O-carboxylate. Cyclic carboxylate can function as a linking group, for example, when an atom in the ring formed is linked to another group.

[0523] As used herein, the term "thiocarboxylate" includes C-thiocarboxylates and O-thiocarboxylates.

[0524] The term "C-thiocarboxylate," as that term is defined herein above, refers to a -C(=S)-OR' terminal group, or a -C(=S)-O- linking group, where R' is as defined herein.

[0525] The term "O-thiocarboxylate," as that term is defined hereinabove, refers to an -OC(=S)R' terminal group, or an -OC(=S)- linking group, where R' is as defined herein.

[0526] Thiocarboxylates can be linear or cyclic. When cyclic, R' and the carbon atom are linked together to form a ring in a C-thiocarboxylate, which is also referred to as a thiolactone. Alternatively, R' and O are linked together to form a ring in an O-thiocarboxylate. Cyclic thiocarboxylates can function as linking groups, for example, when an atom in the ring formed is linked to another group.

[0527] As used herein, the term "carbamate" includes N-carbamates and O-carbamates.

[0528] The term "N-carbamate," as that term is defined hereinabove, refers to an R"OC(=O)-NR'- terminal group, or an -OC(=O)-NR'- linking group, where R' and R'' are as defined herein.

[0529] The term "O-carbamate," as that term is defined hereinabove, refers to an -OC(=O)-NR'R'' terminal group, or an -OC(=O)-NR'- linking group, where R' and R'' are as defined herein.

[0530] Carbamates can be linear or cyclic. When cyclic, R' and a carbon atom are linked together to form a ring in an O-carbamate. Alternatively, R' and O are linked together to form a ring in an N-carbamate. Cyclic carbamates can function as linking groups, for example, when an atom in the ring formed is linked to another group.

[0531] As used herein, the term "carbamate" includes N-carbamates and O-carbamates.

[0532] As used herein, the term "thiocarbamate" includes N-thiocarbamates and O-thiocarbamates.

[0533] The term "O-thiocarbamate," as that term is defined hereinabove, refers to an -OC(=S)-NR'R'' terminal group, or an -OC(=S)-NR'- linking group, where R' and R'' are as defined herein.

[0534] The term "N-thiocarbamate," as that term is defined hereinabove, refers to an R"OC(=S)NR'- terminal group, or an -OC(=S)NR'- linking group, where R' and R'' are as defined herein.

[0535] The thiocarbamates can be linear or cyclic, as described herein for carbamates.

[0536] As used herein, the term "dithiocarbamate" includes S-dithiocarbamates and N-dithiocarbamates.

[0537] The term "S-dithiocarbamate," as that term is defined hereinabove, refers to an -SC(=S)-NR'R'' terminal group, or an -SC(=S)NR'- linking group, where R' and R'' are as defined herein.

[0538] The term "N-dithiocarbamate," as that term is defined hereinabove, refers to an R"SC(=S)NR'- terminal group, or an -SC(=S)NR'- linking group, where R' and R" are as defined herein.

[0539] The term "urea", also referred to herein as "ureido", as that term is defined herein above, refers to an -NR'C(=O)-NR''R''' terminal group, or an -NR'C(=O)-NR''- linking group, where R' and R'' are as defined herein and R''' is as defined herein for R' and R''.

[0540] The term "thiourea," also referred to herein as "thioureido," refers to the -NR'-C(=S)-NR''R''' terminal group, or the -NR'-C(=S)-NR''- linking group, where R', R'' and R''' are as defined herein.

[0541] As used herein, the term "amide" includes C-amides and N-amides.

[0542] The term "C-amido", as that term is defined herein above, refers to a -C(=O)-NR'R'' terminal group, or a -C(=O)-NR'- linking group, where R' and R'' are as defined herein.

[0543] The term "N-amido", as that term is defined herein above, refers to an R'C(=O)-NR''-terminus, or an R'C(=O)-N-linking group, where R' and R'' are as defined herein.

[0544] The amide can be linear or cyclic. When cyclic, R' and the carbon atom are linked together to form a ring in the C-amide, which is also called a lactam. Cyclic amides can function as linking groups, for example, when an atom in the ring formed is linked to another group.

[0545] The term "guanyl," as that term is defined herein above, refers to an R'R''NC(=N)-terminus, or an -R'NC(=N)-linking group, where R' and R'' are as defined herein.

[0546] The term "guanidine," as that term is defined hereinabove, refers to an -R'NC(=N)-NR''R''' terminal group, or an -R'NC(=N)-NR''- linking group, where R', R'', and R''' are as defined herein.

[0547] The term "hydrazine," as that term is defined hereinabove, refers to an -NR'-NR''R''' terminal group, or an -NR'-NR''- linking group, where R', R'', and R''' are as defined herein.

[0548] The term "hydrazide," as used herein, refers to a -C(=O)-NR'-NR''R''' terminal group, or a -C(=O)-NR'-NR''- linking group, as that term is defined herein above, where R', R'', and R''' are as defined herein.

[0549] The term "thiohydrazide," as used herein, refers to a -C(=S)-NR'-NR''R''' terminal group, or a -C(=S)-NR'-NR''- linking group, as that term is defined herein above, where R', R'', and R''' are as defined herein.

[0550] The term "cyanurate" means terminal group JPEG2025501982000003.jpg3848 or a linking group JPEG2025501982000004.jpg3751, where R' and R'' are as defined herein.

[0551] The term "isocyanurate" means terminal group JPEG2025501982000005.jpg4141 or a linking group JPEG2025501982000006.jpg4340, where R' and R'' are as defined herein.

[0552] The term "thiocyanurate" means terminal group JPEG2025501982000007.jpg3847 or a linking group JPEG2025501982000008.jpg3753, where R' and R'' are as defined herein.

[0553] As used herein, the term "alkylene glycol" refers to a -O-[(CR'R'') z -O] y -R''' end group, or -O-[(CR'R'') z -O] y -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 greater than or equal to 1. Preferably, R' and R'' are both hydrogen. When z is 2 and y is 1, the group is ethylene glycol. When z is 3 and y is 1, the group is propylene glycol. When y is 2 to 4, the alkylene glycol is referred to herein as an oligo(alkylene glycol).

[0554] As used herein, an "ethoxylated" material refers to an acrylic or methacrylic compound that contains one or more alkylene glycol groups, or preferably one or more alkylene glycol chains, as defined herein. Ethoxylated (meth)acrylate materials can be monofunctional, or preferably multifunctional, i.e., difunctional, trifunctional, tetrafunctional, etc.

[0555] In multifunctional materials, typically each of the (meth)acrylate groups is linked to an alkylene glycol group or chain, which are linked to each other via branching units, such as, for example, branched alkyl, cycloalkyl, aryl (e.g., bisphenol A), etc.

[0556] 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 be linked together to form an alkylene glycol chain. For example, an ethoxylated material comprising 30 ethoxylated groups can comprise one chain of 30 alkylene glycol groups linked together, two chains, e.g., 15 alkylene glycol moieties linked together, each linked together via a branching moiety, or three chains, e.g., 10 alkylene glycol groups linked together, each linked together via a branching moiety. Shorter and longer chains are also contemplated.

[0557] The ethoxylated material can contain one, two or more alkylene glycol chains of any length.

[0558] As used herein, the term "branching unit" refers to a multi-radical, preferably an aliphatic group or an alicyclic structure. "Multi-radical" means that the unit has two or more attachment points such that there is a connection between two or more atoms and / or groups or moieties.

[0559] In some embodiments, the branching unit is derived from a chemical moiety having two, three or more functional groups, hi some embodiments, the branching unit is a branched alkyl or cycloalkyl (alicyclic) or aryl (e.g., phenyl), as defined herein.

[0560] As used herein, the term "impact resistance", also referred to herein and in the art interchangeably as "impact strength" or simply "impact", refers to the resistance of a material to destruction by mechanical impact and is expressed as the amount of energy absorbed by the material before complete destruction. Impact resistance can be measured, for example, using the Izod impact test (also known as "Izod notch impact" or "Izod impact") of the ASTM D256-06 standard and / or as described below, and is expressed as J / m.

[0561] As used herein, HDT refers to the temperature at which each formulation or combination of formulations deforms under a given load at a particular temperature. A suitable test procedure for determining the HDT of a formulation or combination of formulations is the ASTM D-648 series, particularly the ASTM D-648-06 and ASTM D-648-07 methods. In various exemplary embodiments of the present invention, the core and shell of the structure differ in their HDT measured by the ASTM D-648-06 method and their HDT measured by the ASTM D-648-07 method. In some embodiments of the present invention, the core and shell of the structure differ in their HDT measured by any of the methods of the ASTM D-648 series. In most of the examples herein, HDT at a pressure of 0.45 MPa was used.

[0562] As used herein, the "Tg" of a material refers to the glass transition temperature, defined as the location of the maximum in the E'' curve, where E'' is the loss modulus of the material as a function of temperature.

[0563] Roughly speaking, when heated within a temperature range that includes the Tg temperature, the state of a material, particularly a polymeric material, gradually changes from a glassy state to a rubbery state.

[0564] As used herein, a "Tg range" is a temperature range at which the E" value is at least half of (e.g., can be up to) the Tg temperature defined above.

[0565] Without wishing to be bound by any particular theory, it is hypothesized that the state of the polymeric material gradually changes from a glassy state to a rubbery state within the Tg range defined above, with the lowest temperature in the Tg range being referred to herein as Tg(low) and the highest temperature in the Tg range being referred to herein as Tg(high).

[0566] Throughout this specification, whenever a hardenable material is defined in terms of the properties of the hardened material obtained therefrom, it will be understood that the properties are in terms of the hardened material obtained from the hardenable material itself.

[0567] "Tensile strength" means the maximum stress that a material can withstand while being stretched or pulled until it breaks. Tensile strength may be determined, for example, according to ASTM D-638-03.

[0568] "Tensile modulus" refers to the stiffness of a material, defined as the relationship between stress (force per unit area) and strain (proportional deformation) of the material in the linear elastic region of uniaxial deformation. Tensile modulus may be determined, for example, according to ASTM D-638-04.

[0569] "Flexural strength" or "flexural stress" means the stress of a material just before the material yields in a flexural test. Flexural strength may be determined, for example, in accordance with ASTM D-790-03, unless otherwise specified.

[0570] "Flexural modulus" or "flexural Y modulus" refers to the ratio of stress to strain in bending deformation as determined from the slope of a stress-strain curve obtained by a bending test such as ASTM D790. Flexural modulus may be determined, for example, according to ASTM D-790-04, unless otherwise specified.

[0571] According to some embodiments, flexural strength and flexural modulus are determined according to ISO 20795-1(8.5).

[0572] Throughout this specification, unless otherwise indicated, viscosity values ​​are provided for materials or formulations as measured using a Brookfield viscometer at 25° C. Measurements are provided in centipoise, which corresponds to mPa / sec.

[0573] It will be understood that certain features of the invention are described for clarity in the context of separate embodiments, but may also be provided in combination in a single embodiment. Conversely, various features of the invention that are described for brevity in the context of a single embodiment may also be provided separately or in any suitable subcombination, or as appropriate to any other described embodiment of the invention. Certain features described in the context of various embodiments should not be considered essential features of those embodiments, unless the embodiment is inoperable without those elements.

[0574] Various embodiments and aspects of the present invention as delineated hereinabove and as claimed in the claims section below find experimental support in the following examples. EXAMPLES

[0575] Reference is now made to the following examples which, together with the above descriptions, illustrate certain non-limiting embodiments of the invention.

[0576] [Example 1]

[0577] -design-

[0578] The inventors have been searching for a curable formulation that can be used for additive manufacturing, particularly 3D inkjet printing, of dental prostheses, including denture artificial teeth, denture bases, and preferably integral structures of denture bases and teeth. The inventors have focused on 3D inkjet printing using a system as described in FIG. 1D, which employs an LED radiation source as a curing energy source and can perform a PolyJet printing process. The PolyJet printing process allows for the combination of different formulations of different colors and / or different mechanical properties, and is particularly useful for manufacturing full-color integral structures of denture bases and teeth, and for manufacturing any denture part for an individual.

[0579] The inventors have further sought such a curable formulation that, in addition to meeting 3D printing process requirements (e.g., exhibiting desired viscosity, surface tension, printability, reactivity), also meets regulated dental requirements, in particular exhibiting biocompatibility and mechanical properties as described in ISO 20795-1 dental, ISO 10477 dental, and ISO 10993-1 (Biological safety testing of medical devices (for mucosal contact with prolonged exposure)).

[0580] After extensive research, the inventors have successfully designed and prepared modeling and supporting material formulations that meet the 3D printing process requirements, regulatory requirements, and desired color control. All materials selected for these studies, including curable materials, photoinitiators, dispersants, polymerization inhibitors, and colorants, were selected to be biocompatible according to their toxicity profiles, even upon post-curing and photobleaching.

[0581] The inventors have realized that relatively high molecular weight materials, methacrylate materials, reinforcing materials (fillers), ethoxylated curable materials and multifunctional materials, as well as monofunctional curable materials, should be used to achieve the desired mechanical properties that meet the ISO20795-1 and ISO10477 standards.The inventors have further studied the effects of different materials, such as dispersants for each colorant, polymerization inhibitors, and preparation parameters, to select materials that provide the desired stability and meet the ISO10993-1 requirements.

[0582] As described in more detail below, the inventors have identified a formulation that meets all of the above requirements and can be used to successfully manufacture full-color, one-piece denture structures.

[0583] [Example 2]

[0584] -Exemplary Modeling Formulations-

[0585] Table 1 below lists exemplary curable materials and other ingredients that may be considered for inclusion in modeling material formulations because they are used in medical formulations or have relatively high NOEAL (No Observed Adverse Event Level) values.

[0586] [Table 1]

[0587] Various combinations of these components were used to prepare the formulations shown in Table 2 (e.g., by mixing all ingredients at temperatures up to 50° C.) in various concentrations (expressed as weight % of the total weight of the formulation).

[0588] [Table 2]

[0589] Formulation I is a pigment-free, colorless, transparent, and optionally transmissive formulation that can be used as a base for the CMY (cyan, magenta, and yellow) formulations described herein.

[0590] Formulation II is a white formulation, where Pigment P is a white paste containing 40% white pigment in a mixture of curable (meth)acrylate materials.

[0591] In addition to the formulations shown in Table 2, the following formulations were cast:

[0592] Formulation IX, also referred to herein as WC Formulation, contains a mixture of 80% by weight of Formulation II and the remaining 20% ​​by weight of Formulation I, or a mixture of equal weights (5% by weight each) of Formulation I, Formulation X, Formulation XI and Formulation XII.

[0593] Formulation X - A cyan formulation containing a cyan pigment and the respective pigment dispersant as described herein.

[0594] Formulation XI - A magenta formulation containing a magenta pigment and the respective pigment dispersant as described herein.

[0595] Formulation XII - A yellow formulation containing the yellow pigment and the respective pigment dispersant described herein.

[0596] Formulations X, XI and XII have the composition as Formulation I to which 0.1% to 0.5% by weight of a paste containing a curable material, 0.05% to 0.5% by weight of a selected pigment, and a pigment dispersant are added.

[0597] The cyan, magenta and yellow pigments (ingredient P) in all formulations are preferably nano-milled pigments (not dyes) having an average particle size of less than 1 micrometer, exhibiting good thermal stability and selected from pigments that are suitable for use in food and / or medical devices.

[0598] The pigment dispersants (component Dp) are preferably surfactants approved for food contact printing inks, high molecular weight block copolymers based on polyurethane chemistry, preferably characterized by functional groups with high affinity for the respective pigment. The pigment dispersants Dp may be the same or different for each pigment.

[0599] Table 3 below shows the process parameters for each formulation shown in Table 2.

[0600] Tables 4A-4B below show the mechanical and physical properties required by and measured in accordance with the ISO 20795-1 standard and the respective properties of each of the formulations shown in Table 2.

[0601] Table 5 below shows the mechanical and physical properties required by and measured in accordance with the ISO 10477 standard and the respective properties of each of the formulations shown in Table 2.

[0602] Table 6 below shows the biocompatibility as required by and measured in accordance with the ISO 10993-1 standard and the respective properties of each formulation shown in Table 2.

[0603] [Table 3]

[0604] [Table 4]

[0605] [Table 5]

[0606] The following can be inferred from the data presented in Tables 3, 4A and 4B:

[0607] = The process parameters are not met when the mixture of component B1 and component C is used in an amount greater than 25 wt. %, as in formulation III, or when the silica filler is used in an amount greater than 15 wt. % (see Table 3).

[0608] = When component D1 is used in amounts greater than 15 wt. %, as in formulation V, process parameters and color are adversely affected.

[0609] = In the absence of component C and / or component A, as in formulations VII and VIII, the mechanical properties required by ISO 20795-1 are not met. Addition of component B1, as in formulation VII, improves the mechanical strength but darkens the color.

[0610] = Using component F2 instead of component F1, as in formulation IV, improves mechanical properties, but process parameters are not met and the color becomes darker.

[0611] Thus, Formulations I, II and IX are deemed to meet the process and ISO 20795-1 requirements and were further characterized to meet the requirements of ISO 10477 and ISO 10993-1 as follows.

[0612] [Table 6]

[0613] As can be seen, all formulations meet the requirements of ISO 10477.

[0614] [Table 7]

[0615] As can be seen, all formulations meet the requirements of ISO 10993-1.

[0616] 4 is a photograph of an exemplary denture base and artificial teeth one-piece structure produced by 3D inkjet printing using the AM system shown in FIG. 1D and the exemplary white, transparent, and colored formulations described herein. As can be seen, we have been successful in producing a one-piece structure with precisely controlled colors for each part of the structure.

[0617] [Example 3]

[0618] -Stability-

[0619] Additional studies were performed to evaluate the stability of selected formulations over time.

[0620] FIG. 5 is a comparative plot showing the change in mechanical properties of an object made using Formulation IX according to ISO 20795-1 after one month in water at 37° C. This demonstrates a change of less than 10% which meets the requirements of the ISO 20795-1 standard.

[0621] Table 7 below shows the mechanical properties of an object made using Formulation IX before and after 2 hours of mercury lamp irradiation in water at 37° C. for one month in accordance with ISO 20795-1, demonstrating less than 10% change, which meets the requirements of the ISO 20795-1 standard, indicating that the change in mechanical properties is insignificant and ineffective, thereby meeting the requirements of the ISO 20795-1 standard.

[0622] [Table 8]

[0623] Figures 6A-6B show the dimensional change of the interior portions of exemplary one-piece denture structures made using at least some of Formulation I, Formulation II, Formulation IX, Formulation X, Formulation XI, and Formulation XII (printed in matte mode as described herein) upon immersion in water at 37°C. Figure 6B is a bar graph showing the measured dimensions of exemplary points of the central portion and left and right gingival contact areas of the denture marked with circles in Figure 6A.

[0624] In accordance with the requirements of ISO 20795-1, only a change of less than 200 micrometers was observed after immersion in water for three weeks.

[0625] 7A-7B show the dimensional change of the exterior portion (printed in gloss mode) of an exemplary one-piece denture structure made using at least some of Formulation I, Formulation II, Formulation IX, Formulation X, Formulation XI, and Formulation XII described herein when immersed in water at 37° C. FIG 7B is a bar graph showing the measured dimensions of exemplary upper teeth marked with circles in the upper image of FIG 7A and the measured dimensions at exemplary points of molders and gingiva marked with circles in the lower image of FIG 7A.

[0626] Following the requirements of ISO 20795-1, after immersion in water for three weeks, changes of less than 125 microns were observed on the outer edges and less than 3 microns on the teeth.

[0627] The stability of the formulations on storage was tested by measuring the change in viscosity at 65° C. for 21 days and at 70° C. The data obtained is shown in Table 8 below and shows that there was no substantial change in viscosity, indicating the chemical stability of the formulations.

[0628] [Table 9]

[0629] [Example 4]

[0630] -Support material formulation-

[0631] The inventors have determined that currently available bearing material formulations do not perform optimally in the context of denture structures. As a result, the inventors have successfully designed and implemented a novel formulation that can be used to provide a bearing material. This bearing material formulation can be used in combination with any of the modeling material formulations according to the present embodiments. More specifically, the inventors have identified a need for the inclusion of a multi-functional hardenable material in the bearing material formulation in addition to the hydrophilic monofunctional hardenable materials commonly used in such formulations.

[0632] An exemplary support material formulation according to some embodiments of the present invention comprises: 15% to 25% by weight of a hydrophilic monofunctional (meth)acrylate, preferably a PEGylated acrylate such as PEA6; 10% to 20% by weight of a hydrophilic monofunctional (meth)acrylamide such as HEAA; 1% to 5% by weight of a polyfunctional (e.g., bifunctional) aliphatic / alicyclic (meth)acrylate; and 40% to 60% by weight of a non-curable water-soluble or water-immiscible polymeric material (eg, a polyol or mixture of polyols) as described herein.

[0633] The formulation preferably further comprises a photoinitiator at a concentration of 0.1% to 1% by weight, and optionally a polymerization inhibitor and / or a surfactant.

[0634] The stability of exemplary formulations is shown in Table 8 above.

[0635] While the present invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications, and variations that fall within the spirit and broad scope of the appended claims.

[0636] It is the intention of the applicants that all publications, patents, and patent applications mentioned herein are incorporated herein by reference in their entirety to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated herein by reference. Furthermore, citation or identification of any reference in this application should not be construed as an admission that such reference is available as prior art to the present invention. To the extent section headings are used, they should not be construed as necessarily limiting. Additionally, any priority documents of this application are incorporated herein by reference in their entirety.

Claims

1. 1. A modeling material formulation usable for additive manufacturing of a denture structure, said modeling material formulation comprising: A polyfunctional aliphatic urethane (meth)acrylate (component A) characterized by having a Tg of greater than 100° C. when cured; a polyfunctional non-aromatic (meth)acrylate (component B) characterized by a Tg when cured greater than 100° C.; A filler in the form of micron-sized particles (component C); a polyfunctional ethoxylated aromatic (meth)acrylate (component D), characterized by having less than 10 ethoxylated groups and / or a Tg when cured in the range of 50° C. to 150° C.; A monofunctional (meth)acrylate (component E), A polyfunctional cyclic (meth)acrylate (component F); and A polyfunctional aliphatic urethane (meth)acrylate (component G) characterized in that when cured, it has a Tg of less than 100°C; Including, the amount of the filler is 20% by weight or less, or 15% by weight or less of the total weight of the formulation; the amount of component D is 20 wt% or less, or 15 wt% or less of the total weight of the formulation; Modeling material formulation.

2. 2. The modeling material formulation of claim 1, wherein the amount of component A ranges from 15% to 25% by weight of the total weight of the formulation.

3. 3. The modeling material formulation of claim 1 or claim 2, wherein the amount of component B is no more than 20% by weight, or no more than 15% by weight of the total weight of the formulation.

4. The modeling material formulation of any one of claims 1 to 3, wherein the total amount of component B and component C ranges from about 15% to about 25% by weight of the total weight of the formulation.

5. The modeling material formulation of any one of claims 1 to 4, wherein component B comprises a multifunctional cycloaliphatic (meth)acrylate.

6. The modelling material formulation of any one of claims 1 to 5, wherein the filler particles comprise silica particles.

7. The modeling material formulation of any one of claims 1 to 6, wherein the filler particles have a plurality of hardenable groups attached thereto.

8. The modeling material formulation according to any one of claims 1 to 7, wherein component D is a polyfunctional ethoxylated aromatic (meth)acrylate characterized by having less than 5 ethoxylated groups.

9. 8. The modeling material formulation of claim 1, wherein component D is a multifunctional ethoxylated aromatic (meth)acrylate characterized by having less than 5 ethoxylated groups and a Tg when cured in the range of 50° C. to 150° C.

10. The modeling material formulation according to any one of claims 1 to 9, wherein the monofunctional (meth)acrylate comprises a monofunctional acrylate and a monofunctional methacrylate.

11. The modeling material formulation of claim 10, wherein the weight ratio of the monofunctional acrylate to the monofunctional methacrylate ranges from 2:1 to 1:

2.

12. 12. The modeling material formulation of claim 10 or claim 11, wherein the concentration of each of the monofunctional acrylates and monofunctional methacrylates, independently, ranges from 10% to 20% or from 15% to 20% by weight of the total weight of the formulation.

13. The modelling material formulation according to any one of the preceding claims, wherein the total amount of the at least one monofunctional (meth)acrylate is in the range of 30% to 40% by weight of the total weight of the formulation.

14. The modeling material formulation according to any one of claims 1 to 13, wherein component F is a multifunctional isocyanurate (meth)acrylate.

15. The modelling material formulation according to any one of the preceding claims, wherein component F has a Tg when cured above 150°C, or above 180°C, or above 200°C.

16. A modelling material formulation according to any one of the preceding claims, wherein the concentration of component F is in the range of 5% to 10% by weight of the total weight of the formulation.

17. The modeling material formulation of any one of claims 1 to 16, wherein component G is a multifunctional aliphatic urethane (meth)acrylate having an average molecular weight of at least 1000 grams / mole.

18. A modelling material formulation according to any one of the preceding claims, wherein the concentration of component G is in the range of 5% to 10% by weight of the total weight of the formulation.

19. Component A in an amount ranging from 15% to 25% by weight of the total weight of the formulation; Component B in an amount of 20% by weight or less, or 15% by weight or less, of the total weight of the formulation; Component E in an amount of 30% to 40% by weight of the total weight of the formulation; said component F in an amount of 5% to 10% by weight of the total weight of said formulation; said component G in an amount of 5% to 10% by weight of the total weight of said formulation; 18. The modelling material formulation according to any one of claims 1 to 17, comprising:

20. 20. The modeling material formulation of any one of claims 1 to 19, wherein component A is a difunctional aliphatic urethane methacrylate characterized by a Tg when cured above 100°C.

21. The modeling material formulation of any one of claims 1 to 20, wherein component B is a difunctional cycloaliphatic acrylate characterized by a Tg when cured above 100°C.

22. The modelling material formulation of any one of claims 1 to 21, wherein component C comprises micron-sized silica particles having hardenable groups attached thereto.

23. The modeling material formulation of any one of claims 1 to 22, wherein component D is a difunctional ethoxylated aromatic methacrylate (Component D) characterized by having less than 5 ethoxylated groups and a Tg when cured in the range of 50°C to 150°C.

24. 24. The modeling material formulation of any one of the preceding claims, wherein component E comprises a monofunctional acrylate and a monofunctional methacrylate, each independently in an amount of 10% to 20% or 15% to 20% by weight of the total weight of the formulation.

25. The modeling material formulation of any one of claims 1 to 24, wherein component F is a trifunctional isocyanurate triacrylate.

26. The modeling material formulation of any one of claims 1 to 25, wherein component G is a difunctional aliphatic urethane dimethacrylate characterized by a Tg when cured of less than 100°C and an average molecular weight of at least 1000 grams / mole.

27. The modelling material formulation according to any one of the preceding claims, further comprising a dispersant (component H).

28. 30. The modeling material formulation of claim 27, wherein the dispersant has a curable group.

29. 30. The modeling material formulation of claim 28, wherein the dispersant is a polyfunctional aliphatic silicon (meth)acrylate.

30. The modeling material formulation of any one of claims 27 to 29, wherein the dispersant has an average molecular weight of at least 1000 grams / mole.

31. A modelling material formulation according to any preceding claim, in which the amount of the dispersant is in the range 0.1% to 0.5% by weight of the total weight of the formulation.

32. The modelling material formulation according to any one of claims 1 to 31, further comprising a polymerization inhibitor (component I).

33. The modeling material formulation of any one of claims 1 to 31, further comprising a photoinitiator (component J).

34. 34. The modeling material formulation of claim 33, wherein the amount of the photoinitiator ranges from 1% to 5% by weight of the total weight of the formulation.

35. A modelling material formulation according to any one of the preceding claims, further comprising a colouring agent (component P).

36. 36. The modeling material formulation of claim 35, wherein the colorant comprises a pigment.

37. 37. The modeling material formulation of claim 35 or 36, wherein the colorant comprises a mixture of a pigment and at least one (meth)acrylic material.

38. 38. The modeling material formulation of claim 36 or claim 37, wherein the pigment comprises nano-sized particles.

39. The modelling material formulation according to any one of claims 36 to 38, wherein the colourant further comprises a pigment dispersant (component Dp).

40. A support material formulation which can be used in the additive manufacturing of dental structures, preferably in combination with a modelling material formulation according to any one of claims 1 to 39, a non-curable water-soluble or water-miscible polymeric material in an amount of about 40% to about 60% by weight of the total weight of the formulation; a hydrophilic monofunctional (meth)acrylate in an amount of 15% to 25% by weight of the total weight of the formulation; a hydrophilic monofunctional (meth)acrylamide in an amount of 10% to 20% by weight of the total weight of the formulation; a multifunctional non-aromatic (meth)acrylate in an amount of 1% to 5% by weight of the total weight of the formulation; A support material formulation comprising:

41. 41. The support material formulation of claim 40, further comprising a photoinitiator in an amount of 0.1% to 1% by weight of the total weight of the formulation.

42. A kit comprising at least one modeling material formulation according to any one of claims 1 to 39 and a support material formulation according to claim 40 or claim 41, wherein the at least one modeling material formulation and the support material formulation are individually packaged and contained within the kit.

43. 40. A kit comprising at least two modeling material formulations according to any one of claims 1 to 39, each of the at least two modeling material formulations being individually packaged and contained within the kit, and the at least two modeling material formulations differing from each other by the presence and / or type of colorant.

44. 1. A method for additively manufacturing a three-dimensional prosthetic dental object, the method comprising: dispensing a plurality of layers in a configuration pattern corresponding to a shape of a dental object, thereby forming said dental object; forming each of at least some of the layers includes dispensing at least one formulation and exposing the dispensed formulation to curing conditions, thereby forming a hardened modeling material; The at least one formulation is a modelling material formulation according to any one of claims 1 to 39. method.

45. 45. The method of claim 44, wherein the dispensing comprises dispensing at least two modeling material formulations, each of the at least two modeling material formulations being independently a modeling material formulation according to any one of claims 1 to 39.

46. 46. ​​The method of claim 44 or claim 45, wherein the dispensing further comprises dispensing a support material formulation.

47. 47. The method of claim 46, wherein the support material formulation is a support material formulation as defined in claim 40 or claim 41.

48. The method according to any one of claims 44 to 47, wherein the denture structure is selected from a denture base, an artificial tooth, a plurality of artificial teeth, and an integral structure of a denture base and a plurality of artificial teeth.

49. The method according to any one of claims 44 to 47, wherein the denture structure is an integral structure of a denture base and a plurality of artificial teeth.

50. A denture structure obtainable by the method according to any one of claims 44 to 49.

51. 51. The denture structure of claim 50, which is an integral structure of a denture base and a plurality of artificial teeth.

52. A denture structure according to claim 50 or claim 51, characterised by mechanical and physical properties in accordance with the requirements of ISO 20795-1 and ISO 10477, and biocompatibility in accordance with the requirements of ISO 10993-1.

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