Compositions and methods useful for forming sintered articles

Abstract

To provide sintered articles comprised of fused thermoplastic particles, compositions useful for preparing such sintered articles, as well as methods for obtaining the sintered articles using the compositions.SOLUTION: A sintered article may be formed from a composition containing at least sinterable thermoplastic particles and a curable (meth)acrylate resin component, wherein the sinterable thermoplastic particles are insoluble in the curable (meth)acrylate resin component at 25°C. The curable (meth)acrylate resin component may be cured, thereby forming an intermediate article which may be converted into a sintered article using conditions effective to remove at least a portion of the matrix formed by the cured curable (meth)acrylate resin component and to sinter the thermoplastic particles.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a sintered article composed of fused thermoplastic particles, a composition useful for the preparation of such a sintered article, and a method for obtaining a sintered article using said composition. In particular, the present invention relates to a composition comprising sinterable thermoplastic particles and a curable (meth)acrylate resin component, wherein the curable (meth)acrylate resin component can be cured (e.g., by UV) to form a sacrificial matrix in which the sinterable thermoplastic particles are bound. The cured matrix can then be at least partially removed (e.g., by thermal and / or oxidative decomposition) to fuse the sinterable thermoplastic particles, thereby forming a sintered article. Background Art

[0002] The production of three-dimensional polymer articles using various printing techniques is currently of great interest because 3D printing offers certain processing advantages over conventional methods of forming articles from polymeric materials. Of the three main 3D printing technologies currently available, ultraviolet (UV) curing provides the highest resolution and potentially also the highest production rate. However, the main problem with the use of UV curing technology in 3D printing is that the material used is a radiation-curable acrylate, which provides a thermoset acrylic once cured. Although radiation-curable acrylates have fast cure rates, the products obtained therefrom are generally quite brittle and lack the toughness and yield properties of thermoplastics, and the range of properties that thermoplastics bring (e.g., high service temperature, high chemical resistance). Great efforts have been made to improve the toughness, high temperature stability and strength of such UV-curable systems, but generally speaking, as long as the resulting article is thermosetting in nature, the achievable properties will be limited. Summary of the Invention Problems to be Solved by the Invention

[0003] Therefore, it would be desirable to develop technologies that enable the manufacture of 3D printed materials that are at least substantially thermoplastic in nature. [Means for solving the problem]

[0004] According to one aspect of the present invention, a composition is provided comprising sinterable thermoplastic particles and a curable (meth)acrylate resin component, wherein the sinterable thermoplastic particles are insoluble in the curable (meth)acrylate resin component at 25°C.

[0005] In a further embodiment, the present invention also provides a method for forming a sintered article, a) Curing a composition comprising sinterable thermoplastic particles and a curable (meth)acrylate resin component to form an intermediate article comprising sinterable thermoplastic particles bonded by a matrix of cured curable (meth)acrylate resin components, wherein the sinterable thermoplastic particles are insoluble in the curable (meth)acrylate resin component at 25°C, and b) Removing at least a portion of the matrix from the intermediate article and exposing it to conditions effective for sintering sinterable thermoplastic particles, thereby fusing the sinterable thermoplastic particles to form a sintered article. This provides a method that includes [something].

[0006] A further aspect of the present invention is a method for producing a sintered article, a) A first layer of a composition comprising sinterable thermoplastic particles and a curable (meth)acrylate resin component is applied, wherein the sinterable thermoplastic particles are insoluble in the curable (meth)acrylate resin component at 25°C. b) The first layer is cured to provide a cured first layer. c) Apply a second layer of the composition onto the cured first layer. d) The second layer is cured to provide a cured second layer that is bonded to the cured first layer. e) Repeat steps c) and d) a desired number of times to construct a three-dimensional article composed of sinterable thermoplastic particles bound together by a matrix of curable (meth)acrylate resin components in a cured form, and f) A three-dimensional article is subjected to conditions effective for sintering sinterable thermoplastic particles by removing at least a portion of the matrix, thereby fusing the sinterable thermoplastic particles to form a sintered article. This provides a method that includes [something].

[0007] A method for producing a three-dimensional printed article using a three-dimensional printing method such as digital light projection, stereolithography, or multi-jet printing is provided in an additional embodiment of the present invention, which comprises irradiating a composition comprising sinterable thermoplastic particles and a curable (meth)acrylate resin component layer by layer to form a three-dimensional printed article, wherein the sinterable thermoplastic particles are insoluble in the curable (meth)acrylate resin component at 25°C. [Modes for carrying out the invention]

[0008] The composition of the present invention comprises sinterable thermoplastic particles and a curable (meth)acrylate resin component, wherein the sinterable thermoplastic particles are insoluble in the curable (meth)acrylate resin component at 25°C. As used herein, the term “insoluble” means that when 5 parts by weight of sinterable thermoplastic particles and 95 parts by weight of the curable (meth)acrylate resin component are mixed and the resulting mixture is allowed to stand at 25°C for 24 hours, less than 10% of the thermoplastic particles present in the sinterable thermoplastic particles dissolve in the curable (meth)acrylate resin component.

[0009] In certain embodiments of the present invention, the composition at room temperature (25°C) is in the form of a dispersion of sinterable thermoplastic particles (solid particle form) in a liquid matrix of a curable (meth)acrylate resin component. In one embodiment, the sinterable thermoplastic particles are homogeneously dispersed in the liquid matrix of the curable (meth)acrylate resin component. According to another embodiment, the sinterable thermoplastic particles are in the form of a stable, homogeneous dispersion in the liquid matrix of the curable (meth)acrylate resin component. In this context, “homogeneous” means that the sinterable thermoplastic particles are evenly and uniformly distributed throughout the volume of the composition when observed with the naked eye, and “stable” means that after the composition is stirred to achieve a homogeneous state and then allowed to stand at 25°C, the dispersion remains homogeneous for at least 24 hours. To help improve the homogeneity and stability of the dispersion, one or more dispersants (such as surfactants) may be included in the composition.

[0010] Sinterable thermoplastic particles The sinterable thermoplastic particles useful in the present invention are composed of at least one thermoplastic material, i.e., a polymer that can be melted when heated. The thermoplastic particles are sinterable, and in the context of the present invention, this means that the thermoplastic particles can be formed into a coherently bonded mass by heating and / or compressing them without melting the thermoplastic particles until they reach a point of complete liquefaction. Typically, the sinterable thermoplastic particles are in the form of a fine powder. For example, the sinterable thermoplastic particles can have a volume median diameter (Dv50) of preferably 5 microns to 3 mm, more preferably 10 to 300 microns, and most preferably 15 to 100 microns, as measured by scanning electron microscopy when dry. The bulk density of the sinterable thermoplastic particles is preferably 0.1 g / cm³. 3 Larger than that, and more preferably 0.3 g / cm³ 3 Larger than, or most preferably 0.4 g / cm³ 3 It can do more than that.

[0011] Sinterable thermoplastic particles according to one aspect of the present invention may consist mainly of substantially spherical particles, but other shapes (including irregular shapes) may also be employed. Sinterable thermoplastic particles may be crushed, surface modified, or subjected to other processing to alter the flow properties or other properties of the sinterable thermoplastic particles. Sinterable thermoplastic particles may also contain one or more additives in addition to the thermoplastic material, such as fillers, flowing agents, crystallization accelerators, or inhibitors. Sinterable thermoplastic particles may also contain a blend of one or more suitable thermoplastic materials with other thermoplastic materials or additives.

[0012] A suitable thermoplastic material includes a polymer that functions well in the compositions described herein when subjected to the manufacturing conditions of three-dimensional objects in a three-dimensional printing press. The thermoplastic material may be one of the so-called engineering thermoplastics known in the art. However, other types of thermoplastics can also be used. For example, a thermoplastic material present in sinterable thermoplastic particles may have a melting point of 150°C or higher and / or a Tg of 100°C or higher. In other embodiments, the thermoplastic material may have a melting point of 250°C and / or a Tg of 200°C or higher. The melting point of the thermoplastic material is measured by differential scanning calorimetry (DSC) during the second heating cycle using the following temperature cycle.

[0013] - Heat from 20 to 400°C at a rate of 10°C / min. - Cool from 400°C to 20°C at a rate of 1°C / min. - Heat from 20°C to 400°C at a rate of 10°C / min.

[0014] The glass transition temperature of thermoplastic materials is measured by differential scanning calorimetry (DSC), particularly during the second heating cycle at 20°C / min according to ISO 11357.

[0015] Thermoplastic materials can be amorphous, crystalline, or semi-crystalline.

[0016] Examples of suitable thermoplastics include polyaryletherketones (PAEK), polyamides, polyimides, and fluoropolymers. The term polyaryletherketone refers to a polymer whose molecular skeleton contains both ketone (R-CO-R) and ether groups (ROR), and in which the bonding group R between functional groups consists of a disubstituted aryl group, and is intended to encompass all homopolymers and copolymers (including, for example, terpolymers). In one embodiment, the polyaryletherketone is selected from the group consisting of polyetherketone ketone (PEKK), polyetheretherketone (PEEK), polyetherketone (PEK), polyetherketone etherketone ketone (PEKEKK), and mixtures thereof.

[0017] In one embodiment, the polyaryletherketone comprises polyetherketone ketone (PEKK). Polyetherketone ketones suitable for use in embodiments of the present invention may contain, essentially consist of, or comprise repeating units represented by the following formulas I and II.

[0018] -AC(=O)-BC(=O)- I -AC(=O)-DC(=O)- II In the formula, A is a p,p'-Ph-O-Ph group, Ph is a phenylene group, B is p-phenylene, and D is m-phenylene. The ratio of the Formula I:Formula II (T:I) isomers in polyether ketone ketone can be 100:0 to 0:100. The isomer ratio can be easily varied as may be desired to achieve a particular set of properties, for example, by varying the relative amounts of the different monomers used to prepare the polyether ketone ketone. Generally, polyether ketone ketones having a relatively higher ratio of Formula I:Formula II are more crystalline than polyether ketone ketones having a lower ratio of Formula I:Formula II. Accordingly, the T:I ratio can be adjusted to provide an amorphous (non-crystalline) polyether ketone ketone or a more crystalline polyether ketone ketone, as desired. In one embodiment, polyether ketone ketone having a T:I isomer ratio of from about 50:50 to about 90:10 may be used.

[0019] For example, the chemical structure of polyether ketone ketone having all para-phenylene linkages [PEKK(T)] can be represented by Formula III.

[0020]

化

[0021] The chemical structure of polyether ketone ketone having one meta-phenylene linkage in the backbone [PEKK(I)] can be represented by Formula IV.

[0022]

化

[0023] The chemical structure of a polyether ketone ketone having alternating T and I isomers, for example a homopolymer [PEKK(T / I)] having a chemical composition of 50% each of T and I, can be represented by Formula V.

[0024]

化

[0025] In another embodiment, the polyaryletherketone includes polyetheretherketone (PEEK). A polyetheretherketone suitable for use in the present invention may include, essentially consist of, or consist of repeating units (n≧1) represented by formula VI.

[0026] [ka]

[0027] In another embodiment, the polyaryletherketone comprises polyetherketone (PEK). A polyetherketone suitable for use in the present invention may contain, essentially consist of, or consist of repeating units (n≧1) represented by formula VII.

[0028] [ka]

[0029] Polyaryl ether ketones can be prepared by any suitable method, and such methods are well known in the art. For example, polyaryl ether ketones can be formed by heating a substantially equimolar mixture of at least one bisphenol and at least one dihalobenzoid compound or at least one halophenol compound. The polymer can be amorphous or crystalline, which can be controlled by the synthesis of the polymer. Thus, the polymer(s) can vary from amorphous to highly crystalline depending on the intended use and industrial application of the coated wire. Furthermore, the polymer(s) can also be of any suitable molecular weight and may be functionalized or sulfonated if desired. In one embodiment, the polymer(s) undergo sulfonation or surface modification of any example known to those skilled in the art.

[0030] Suitable polyetherketones are available from several commercial sources under various trademarks. For example, polyetherketone polymers are manufactured and supplied by Arkema under the trademark Kepstan(R).

[0031] Exemplary polyamides (nylon) include, in particular, aliphatic polyamides, aromatic polyamides, amorphous and semicrystalline polyamides (PA) 6, PA11, PA12, and aliphatic-aromatic polyamides, as well as copolyamides 6.6, 6.12, 6.10, 10.10, and 10.12. Exemplary polyimides include aliphatic, semi-aromatic, and particularly aromatic polyimides, such as polyimides obtained by reacting a tetracarboxylic dianhydride (e.g., pyromellitic anhydride) with a diprimer diamine (e.g., 4,4'-oxydianiline) to obtain an intermediate polyamide-acid, which can be converted to the corresponding polyimide by one of several suitable methods such as chemical treatment or heat treatment. Typically, suitable polyimides contain a phthalimide structure in the polyimide backbone. Exemplary fluoropolymers include, in particular, polyvinylidene fluoride (including homopolymers of vinylidene fluoride and copolymers of vinylidene fluoride with one or more other monomers such as hexafluoropropylene, chlorotrifluoroethylene and / or tetrafluoroethylene). Suitable PVDF resins for use in the present invention include PVDF resins sold by Arkema under the trademark Kynar(R). Examples of other suitable fluoropolymers include PTFE, FEP, PCTFE, ETFE, MFA, EFEP, THV, and HTE. Suitable polycarbonates include, for example, polycarbonates prepared from dialcohols (particularly aromatic dialcohols, e.g., bisphenol A and other bisphenols) and phosgene, or their equivalents such as carbonate esters.

[0032] In certain embodiments of the present invention, sinterable thermoplastic particles may be present in the composition in an amount effective to constitute 20-80%, preferably 25-60%, and most preferably 35-50%, of the total weight of the sinterable thermoplastic particles and curable (meth)acrylate resin components. Mixtures of different sinterable thermoplastic particles can be utilized.

[0033] Curable (meth)acrylate resin component In various embodiments of the present invention, the curable (meth)acrylate resin component can be present in the composition in an amount effective to constitute 20-80%, preferably 40-75%, and most preferably 50-65%, of the total weight of the sinterable thermoplastic particles and the curable (meth)acrylate resin component.

[0034] The curable (meth)acrylate resin component used in the compositions of the present invention is characterized by containing, essentially comprising, or consisting of at least one (meth)acrylate-functionalized compound. In certain embodiments, the curable (meth)acrylate resin component is composed of two, three, four or more different (meth)acrylate-functionalized compounds. A (meth)acrylate-functionalized compound can be described as an organic compound having one or more (meth)acrylate functional groups per molecule. As used herein, the term "(meth)acrylate" refers to both acrylate functional groups and methacrylate functional groups. A (meth)acrylate-functionalized compound suitable for use in the present invention can generally be described as an ethylenically unsaturated compound (a compound containing at least one α,β-unsaturated ester moiety) containing at least one carbon-carbon double bond α relative to an ester group, which can participate in a free radical reaction or anionic reaction, particularly a reaction initiated by ultraviolet radiation or electron beam radiation. Such reactions can result in polymerization or curing in which the (meth)acrylate-functionalized compound becomes part of the polymerization matrix or polymer chain. In various embodiments of the present invention, the (meth)acrylate-functionalized compound may contain one, two, three, four, five or more (meth)acrylate functional groups per molecule. The curable (meth)acrylate resin component used in the present invention can utilize a combination of multiple (meth)acrylate-functionalized compounds containing different numbers of (meth)acrylate groups.

[0035] Therefore, the curable (meth)acrylate resin component used in the present invention may include one or more (meth)acrylate-functionalized compounds that can undergo free radical polymerization and / or anionic polymerization (curing) initiated by exposure to ultraviolet or electron beam radiation. As used herein, the term "(meth)acrylate" refers to the methacrylate (-OC(=O)-C(CH3)=CH2) functional group and the acrylate (-OC(=O)-CH=CH2) functional group. The (meth)acrylate-functionalized compound may be an oligomer or monomer, or a combination of oligomers and monomers.

[0036] The (meth)acrylate-functionalized compounds(s) used in the curable (meth)acrylate resin component may be selected to provide a polymer matrix having desired or required properties with respect to transforming the intermediate article obtained when curing the curable (meth)acrylate resin component into a sintered article, once cured. For example, the (meth)acrylate-functionalized compounds(s) may contain one or more parts that are particularly susceptible to thermal and / or oxidative decomposition, thereby the matrix of the cured form of the curable (meth)acrylate resin component present in the intermediate article decomposes when heated and / or exposed to oxidative conditions, producing lower molecular weight and / or volatile decomposition products that can be removed from the intermediate product. In one embodiment, the cured matrix is ​​converted at least partially into a gaseous product, which is then separated from the intermediate article by any suitable method, such as by vacuum and / or by passing a gaseous stream over and / or through the intermediate article. Once the gaseous products are thus removed from the intermediate article, further processing (calcination) of the intermediate article may be carried out to produce a sintered article, as will be described in more detail below. In other embodiments, the decomposition of the cured matrix, the removal of gaseous decomposition products generated from the cured matrix, and the calcination of thermoplastic particles may occur simultaneously. The decomposition of the matrix obtained by curing the curable (meth)acrylate resin component may occur simultaneously with the removal of gaseous decomposition products and / or the calcination of thermoplastic particles to form a sintered article. In another embodiment, at least a portion of the decomposition products are relatively low molecular weight, non-gaseous substances that are soluble in a solvent, allowing for the removal of such decomposition products by washing the intermediate article that has been processed while the sinterable thermoplastic particles are not dissolved.

[0037] Any of the following types of (meth)acrylate functionalized compounds, namely monomers such as (meth)acrylate esters of aliphatic monoalcohols, (meth)acrylate esters of alkoxylated aliphatic monoalcohols, (meth)acrylate esters of aliphatic polyols, (meth)acrylate esters of alkoxylated aliphatic polyols, (meth)acrylate esters of aromatic ring-containing alcohols, and (meth)acrylate esters of alkoxylated aromatic ring-containing alcohols, as well as oligomers such as epoxy (meth)acrylate, polyether (meth)acrylate, urethane (meth)acrylate, polyester (meth)acrylate (including its amine and sulfide-modified derivatives), and any combination thereof, can be used, for example, in the curable (meth)acrylate resin component of the present invention.

[0038] Suitable (meth)acrylate-functionalized oligomers include, for example, polyester (meth)acrylate, epoxy (meth)acrylate, polyether (meth)acrylate, urethane (meth)acrylate (sometimes called polyurethane (meth)acrylate or urethane (meth)acrylate oligomer), and combinations thereof, as well as amine-modified and sulfide-modified versions thereof.

[0039] Exemplary polyester (meth)acrylates include reaction products of acrylic acid or methacrylic acid, or mixtures thereof, with hydroxyl-terminated polyester polyols. The reaction method may be carried out so that a considerable concentration of residual hydroxyl groups remains in the polyester (meth)acrylate, or so that all or essentially all of the hydroxyl groups of the polyester polyol are (meth)acrylicated. Polyester polyols can be produced by polycondensation reactions of polyhydroxyl-functional components (particularly diols) and polycarboxylic acid-functional compounds (particularly dicarboxylic acids and anhydrides). To prepare polyester (meth)acrylates, the hydroxyl groups of the polyester polyol are then partially or completely esterified by reaction with (meth)acrylic acid, (meth)acryloyl chloride, (meth)acrylic anhydride, etc. Polyester (meth)acrylates may also be synthesized by reacting hydroxyl-containing (meth)acrylates, such as hydroxyalkyl (meth)acrylates (e.g., hydroxyethyl acrylate), with polycarboxylic acids. The polyhydroxyl functional components and polycarboxylic acid functional components may each have linear, branched, cyclic aliphatic, or aromatic structures and can be used individually or as a mixture.

[0040] Suitable examples of epoxy (meth)acrylates include reaction products of acrylic acid or methacrylic acid or mixtures thereof with glycidyl ether or ester.

[0041] Examples of polyether (meth)acrylate oligomers include, but are not limited to, condensation reaction products of acrylic acid or methacrylic acid or mixtures thereof with polyether polyols, or polyetherols. Suitable polyetherols can be linear or branched substances containing ether links and terminal hydroxyl groups. Polyetherols can be prepared by ring-opening polymerization of epoxides and other oxygen-containing heterocyclic compounds (e.g., ethylene oxide, 1,2-propylene oxide, butene oxide, tetrahydrofuran, and combinations thereof) with starter molecules. Suitable starter molecules include water, hydroxyl-functional materials, polyester polyols, and amines. Polyetherols can also be obtained by condensation of diols such as glycols.

[0042] The urethane (meth)acrylates (sometimes called "polyurethane (meth)acrylates") that can be used in the curable compositions of the present invention include aliphatic and / or aromatic polyester polyols, polyether polyols and polycarbonate polyols, as well as urethanes based on aliphatic and / or aromatic polyester diisocyanates and polyether diisocyanates, which are capped with (meth)acrylate terminal groups.

[0043] In various embodiments, urethane (meth)acrylates can be prepared by reacting an aliphatic and / or aromatic polyisocyanate (e.g., diisocyanate, triisocyanate) with an OH-terminated polyester polyol (including aromatic, aliphatic, and mixed aliphatic / aromatic polyester polyols), polyether polyol, polycarbonate polyol, polycaprolactone polyol, polydimethisiloxane polyol, or polybutadiene polyol, or a combination thereof, to form an isocyanate-functionalized oligomer, and then reacting the oligomer with a hydroxyl-functionalized oligomer such as hydroxyethyl (meth)acrylate or hydroxypropyl (meth)acrylate to provide terminal (meth)acrylate groups. For example, urethane (meth)acrylates may contain two, three, four or more (meth)acrylate functional groups per molecule. As is known in the art, other addition sequences can also be performed to prepare polyurethane (meth)acrylates. For example, a hydroxyl-functionalized (meth)acrylate can be first reacted with a polyisocyanate to obtain an isocyanate-functionalized (meth)acrylate, which can then be reacted with an OH-terminated polyester polyol, polyether polyol, polycarbonate polyol, polycaprolactone polyol, polydimethisiloxane polyol, polybutadiene polyol, or a combination thereof. In yet another embodiment, a polyisocyanate can be first reacted with a polyol (including any of the aforementioned types of polyols) to obtain an isocyanate-functionalized polyol, which can then be reacted with a hydroxyl-functionalized (meth)acrylate to obtain a polyurethane (meth)acrylate. Alternatively, all components may be reacted simultaneously in combination.

[0044] Any of the aforementioned types of oligomers can be modified with an amine or sulfide (e.g., thiol) according to procedures known in the art. Such amine and sulfide-modified oligomers can be prepared, for example, by reacting a relatively small amount (e.g., 2-15%) of (meth)acrylate functional groups present in the base oligomer with an amine (e.g., secondary amine) or sulfide (e.g., thiol), where the modified compound is added to the carbon-carbon double bond of the (meth)acrylate in a Michael addition reaction.

[0045] Exemplary examples of suitable monomer (meth)acrylate functionalized compounds include (meth)acrylated monoalcohols, (meth)acrylated polyols (polyalcohols), (meth)acrylated alkoxylated monoalcohols, and (meth)acrylated alkoxylated polyols. The monoalcohols and polyols may be aliphatic (containing one or more cyclic aliphatic rings) or may contain one or more aromatic rings (as in the case of phenol or bisphenol A). "Alkoxylation" means that the base monoalcohol or polyol has reacted with one or more epoxides, such as ethylene oxide and / or propylene oxide, to introduce one or more ether moieties (e.g., -CH2CH2-O-) to one or more hydroxyl groups of the monoalcohol or polyol, prior to esterification for introducing one or more (meth)acrylate functional groups. For example, the amount of epoxide reacting with the monoalcohol or polyol can be about 1 to about 30 moles of epoxide per mole of monoalcohol or polyol. Suitable monoalcohols include, but are not limited to, linear, branched, and cyclic C1-C54 monoalcohols (which can be primary, secondary, or tertiary alcohols). For example, the monoalcohol can be a C1-C7 aliphatic monoalcohol. In another embodiment, the monoalcohol may be a C8-C24 aliphatic monoalcohol (e.g., lauryl alcohol, stearyl alcohol). The monoalcohol may also be a monoalkyl ether of a diol (e.g., glycol) or a monoalkyl ether of a polyoxyalkylene glycol such as polyethylene glycol, where the alkyl group can be, for example, a C1-C8 alkyl group. Suitable polyols include glycols (diols), organic compounds containing two, three, four or more hydroxyl groups per molecule, such as ethylene glycol, 1,2- or 1,3-propylene glycol, or 1,2-, 1,3- or 1,4-butylene glycol, neopentyl glycol, trimethylolpropane, triethylolpropane, pentaerythritol, and glycerol.

[0046] Representative, but non-limiting, examples of suitable monomer (meth)acrylate functionalized compounds include 1,3-butylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, and long-chain aliphatic di(meth)acrylates (e.g., formula H2C=CRC(=O)-O-(CH2)). m-OC(=O)CR'=CH2 (wherein R and R' are independently H or methyl, and m is an integer from 8 to 24), alkoxylated (e.g., ethoxylated, propoxylated) hexanediol di(meth)acrylate, alkoxylated (e.g., ethoxylated, propoxylated) neopentyl glycol di(meth)acrylate, dodecyl di(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, diethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, alkoxylated (e.g., ethoxylated, propoxylated) bisphenol A di(meth)acrylate, ethylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, tricyclodecanedimethanol diacrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate , Tripropylene glycol di(meth)acrylate, Ditrimethylolpropane tetra(meth)acrylate, Dipentaerythritol penta(meth)acrylate, Alkoxylated (e.g., ethoxylated, propoxylated) pentaerythritol tetra(meth)acrylate, Dipentaerythritol penta(meth)acrylate, Pentaerythritol tetra(meth)acrylate, Alkoxylated (e.g., ethoxylated, propoxylated) trimethylolpropane tri(meth)acrylate, Alkoxylated (e.g., ethoxylated, propoxylated) glyceryl tri(meth)acrylate, Trimethylolpropane tri(meth)acrylate, Pentaerythritol tri(meth)acrylate, Tris(2-hydroxyethyl) isocyanurate tri(meth)acrylate, 2(2-ethoxyethoxy)ethyl(meth)acrylate, 2-phenoxyethyl(meth)acrylate, 3,3,5-Trimethylcyclohexyl (meth)acrylate, alkoxylated lauryl (meth)acrylate, alkoxylated phenol (meth)acrylate, alkoxylated tetrahydrofurfuryl (meth)acrylate, caprolactone (meth)acrylate, cyclic trimethylolpropaneformal (meth)acrylate, dicyclopentadienyl (meth)acrylate, diethylene glycol methyl ether (meth)acrylate, alkoxylated (e.g., ethoxylated, propoxylated) nonylphenol (meth)acrylate Isobornyl (meth)acrylate, isodecyl (meth)acrylate, isooctyl (meth)acrylate, lauryl (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, octyldecyl (meth)acrylate (also known as stearyl (meth)acrylate), tetrahydrofurfuryl (meth)acrylate, tridecyl (meth)acrylate, triethylene glycol ethyl ether (meth)acrylate, t-butylcyclohexyl (meth)acrylate, dicyclopentadi Endi(meth)acrylate, phenoxyethanol(meth)acrylate, octyl(meth)acrylate, decyl(meth)acrylate, dodecyl(meth)acrylate, tetradecyl(meth)acrylate, cetyl(meth)acrylate, hexadecyl(meth)acrylate, behenyl(meth)acrylate, diethylene glycol ethyl ether(meth)acrylate, diethylene glycol butyl ether(meth)acrylate, triethylene glycol methyl ether(meth)acrylate, dodecanediol(meth)acrylate Examples include tris(2-hydroxyethyl) isocyanurate tri(meth)acrylate, dipentaerythritol penta / hexa(meth)acrylate, pentaerythritol tetra(meth)acrylate, alkoxylated (e.g., ethoxylated, propoxylated) pentaerythritol tetra(meth)acrylate, di-trimethylolpropane tetra(meth)acrylate, alkoxylated (e.g., ethoxylated, propoxylated) glyceryl tri(meth)acrylate, and tris(2-hydroxyethyl) isocyanurate tri(meth)acrylate, as well as combinations thereof.

[0047] To obtain a polymer matrix by curing a curable (meth)acrylate resin component that can be thermally and / or oxidatively decomposed into gaseous and / or soluble products that can be separated from residual sinterable thermoplastic particles present in the intermediate article, the curable (meth)acrylate resin component may be formulated to contain a relatively high proportion of oxyalkylene segments (particularly polyoxyalkylene segments). Oxyalkylene segments generally have the structural formula -C-(C) n-O- corresponds to the carbon atom, which is aliphatic and may be substituted or unsubstituted, and n is an integer greater than or equal to 2 (e.g., 2 to 4). For example, oxyalkylene segments can be -CH2CH2-O-, -CH2CH(CH3)O-, -CH2CH2CH2-O-, -CH2CH2CH2CH2-O-, etc. Suitable polyoxyalkylene segments include, but are not limited to, polyoxyethylene, polyoxypropylene, or polyoxyethylene / oxypropylene segments. Oxyalkylene or polyoxyalkylene segments include, for example, alkoxypolyethylene glycol mono(meth)acrylate (i.e., polyethylene glycol containing alkyl ether and (meth)acrylate terminal groups), alkoxypolypropylene glycol mono(meth)acrylate (i.e., polypropylene glycol containing alkyl ether and (meth)acrylate terminal groups), polyethylene glycol di(meth)acrylate (i.e., polyethylene glycol containing two (meth)acrylate terminal groups), and alkoxylated bis-phenol di(meth)acrylate (i.e., bis- The curable (meth)acrylate functionalized monomer or oligomer may be supplied by one or more (meth)acrylate functionalized monomers or oligomers selected from the group consisting of bisphenol (such as phenol A, which is alkoxylated by reaction with one or more alkylene oxides such as ethylene oxide and / or propylene oxide, and then (meth)acrylated) and alkoxylated aliphatic polyalcohol (meth)acrylates (i.e., aliphatic polyalcohols such as glycols, glycerols, pentaerythritol, trimethiolpropane, sugar alcohols, sugars, etc., which are partially or completely (meth)acrylated after reaction with one or more alkylene oxides). In various embodiments of the present invention, the curable (meth)acrylate resin component may consist of at least 10% by weight, at least 20% by weight, at least 30% by weight, at least 40% by weight, at least 50% by weight, or at least 60% by weight of [poly]oxyalkylene segments in total.Generally, in order for a (meth)acrylate resin component to be curable by photopolymerization or the like, it is recognized that the (meth)acrylate resin component must contain a certain amount of structural parts other than [poly]oxyalkylene segments (e.g., (meth)acrylate functional groups). Therefore, to facilitate the decomposition and removal of the cured matrix formed from the (meth)acrylate resin component, a higher content of [poly]oxyalkylene segments is preferable.

[0048] According to preferred embodiments of the present invention, the composition of the curable (meth)acrylate resin component is selected such that the curable (meth)acrylate resin component is a homogeneous (single-phase) liquid at 25°C and its viscosity at 25°C is not excessive. Formulating the curable (meth)acrylate resin component to have a relatively low viscosity facilitates mixing of the curable (meth)acrylate resin component with sinterable thermoplastic particles, which helps provide an obtained composition that can be easily handled and further processed according to the present invention. In various embodiments of the present invention, for example, the curable (meth)acrylate resin component has a viscosity of preferably less than 1500 centipoise, more preferably less than 800 centipoise, or most preferably less than 500 centipoise at 25°C. The viscosity can be measured using a Brookfield viscometer.

[0049] Photoinitiator When a curable composition is cured using light such as ultraviolet light, it is generally desirable to formulate the composition to include one or more photoinitiators. However, when electron beam or chemical curing is used, the curable composition does not need to contain a photoinitiator.

[0050] A photoinitiator is a compound that undergoes a photoreaction upon absorption of light, generating an active species. The generated reactive species then initiate the polymerization of the reactive components of the curable (meth)acrylate resin component. Generally speaking, if the compounds present in the curable (meth)acrylate resin component contain carbon-carbon double bonds, such polymerization (curing) involves reactions of such carbon-carbon double bonds. In various embodiments of the present invention, the active species can be, for example, free radical species or anionic species. Suitable photoinitiators include, for example, alpha-hydroxy ketones, phenylglyoxylates, benzyldimethyl ketals, alpha-amino ketones, mono-acylphosphines, bis-acylphosphines, metallocenes, phosphine oxides, benzoin ethers, and benzophenones, as well as combinations thereof.

[0051] When a photoinitiator is used in a composition, it can generally be present in a total concentration of up to about 15% by weight based on the total weight of the curable (meth)acrylate resin component (for example, a concentration of about 0.1 to about 5% by weight based on the total weight of the curable (meth)acrylate resin component).

[0052] Other ingredients The compositions of the present invention may optionally consist of one or more components in addition to the components described above. For example, the composition may include at least one stabilizer that helps maintain the homogeneity of the composition so as to prevent or delay the sedimentation of sinterable thermoplastic particles when the composition is left standing for a long period of time. That is, such a stabilizer helps maintain the composition as a relatively uniform suspension or dispersion of sinterable thermoplastic particles in a liquid matrix of curable (meth)acrylate resin components. Stabilizers such as surfactants may be used, and special surfactant packages known in the art may also be used to suit specific thermoplastic materials.

[0053] Furthermore, a flow accelerator or non-reactive solvent can be added, for example, in an amount of 1 to 15% by weight, to reduce the resin viscosity and allow for a higher weight percentage of sinterable thermoplastic particles to be filled. Next, before final processing, the solvent can be removed from the cured intermediate article by evaporation or solvent extraction.

[0054] Method for forming sintered articles The compositions of the present invention are useful for forming sintered articles. Such sintered articles are generally formed by, for example, the following steps: a) A composition according to any of the above embodiments, comprising sinterable thermoplastic particles and a curable (meth)acrylate resin component, is cured to form an intermediate article composed of sinterable thermoplastic particles bound together by a matrix of curable (meth)acrylate resin components in a cured form, and b) Removing at least a portion of the matrix from the intermediate article and exposing it to conditions effective for sintering sinterable thermoplastic particles, thereby fusing the sinterable thermoplastic particles to form a sintered article. It can be obtained by a method that includes [a specific method].

[0055] The curable (meth)acrylate resin component can be cured (including partially or completely cured) by free radical polymerization or other types of polymerization (e.g., anionic polymerization or cationic polymerization). The composition comprising sinterable thermoplastic particles and the curable (meth)acrylate resin component may be in any suitable or appropriate physical form, such as a layer on a substrate or a shape defined by a mold. In certain embodiments, the composition is a freely flowing liquid at 25°C. In other embodiments, the composition is a paste or semi-solid at 25°C.

[0056] The curing of the curable (meth)acrylate resin component according to the present invention can be carried out by any suitable method such as free radical polymerization, cationic polymerization, and / or anionic polymerization. The curable (meth)acrylate resin component may contain one or more initiators, such as free radical initiators (e.g., photoinitiators, peroxide initiators). Before curing, the composition can be applied to the substrate surface by any known conventional method, such as spraying, knife coating, roll coating, casting, drum coating, dipping, extrusion, and combinations thereof. If desired, the composition can also be constrained or molded in some way, including by placing it in a mold, cavity, etc. Indirect application using a transfer method can also be used. The substrate can be any commercially available substrate, such as a metal substrate or a plastic substrate. The substrate can include thermoplastics such as metal, paper, cardboard, glass, polyolefin, polycarbonate, acrylonitrile butadiene styrene (ABS), and blends thereof, composite materials, wood, leather, and combinations thereof.

[0057] The curable (meth)acrylate resin component can be subjected to conditions effective in achieving at least partial curing. For example, curing of at least 25%, or at least 50%, or at least 80%, or at least 90% of the (meth)acrylate resin component can be achieved in various embodiments of the present invention. As used herein, the term “percentage of curing” refers to the percentage of reacted (meth)acrylate functional groups in the starting curable (meth)acrylate resin component, the degree of such reaction can be calculated by a spectroscopic method that includes measuring the concentration of carbon-carbon double bonds present in such (meth)acrylate functional groups before and after being subjected to curing conditions.

[0058] Generally speaking, it is desirable to cure the curable (meth)acrylate resin component to a degree that is effective in providing an intermediate article that is dimensionally stable at the adopted processing temperature (for example, dimensionally stable at room temperature or 15°C to 30°C). In certain embodiments, the curable (meth)acrylate resin component changes from a liquid state to a gel or semi-solid (relatively soft) state at 25°C during curing. In other embodiments, the curable (meth)acrylate resin component changes from a liquid state to a solid (relatively hard) state at 25°C during curing.

[0059] Curing can be accelerated or promoted by supplying energy to the curable (meth)acrylate resin component, for example by heating the composition, and / or by exposing the composition to a radiation source such as visible light or ultraviolet, infrared radiation, and / or electron beam radiation. Thus, the cured matrix can be considered as a reaction product of the curable (meth)acrylate resin component formed by curing. The intermediate product thus obtained may be characterized by containing a cured matrix obtained by curing the curable (meth)acrylate resin component, and containing sinterable thermoplastic particles within it. The sinterable thermoplastic particles may be separate particles that are at least partially in contact with each other or embedded in the cured matrix and separated from each other by the cured matrix.

[0060] The curable (meth)acrylate resin component used in the present invention is preferably formulated to be curable using LED (light-emitting diode) curing (e.g., UV LED curing using radiation from a UV LED device) and / or usable for high-speed coating (such as in three-dimensional printing).

[0061] Multiple layers of the curable composition according to the present invention can be applied to the surface of a substrate, and the multiple layers may be cured simultaneously (for example, by exposure to a single dose of radiation), or each layer may be cured sequentially before the application of additional layers of the curable composition.

[0062] The compositions described herein are useful as 3D printing resin formulations, i.e., compositions intended for use in the manufacture of three-dimensional articles using 3D printing technology. Such three-dimensional articles may be independent / self-contained and may consist essentially of, or be derived from, compositions according to the present invention, which have been cured to react with the curable (meth)acrylate resin component portion of the composition.

[0063] A method for producing a three-dimensional article using a composition according to the present invention is as follows: a) A step of applying a first layer of the composition according to the present invention to a surface, b) The step of curing the first layer (completely or partially) to provide a cured first layer, c) The step of applying a second layer of the composition onto the cured first layer, d) The step of curing the second layer (completely or partially) to provide a cured second layer adhered to the cured first layer, and e) Repeat steps c) and d) a desired number of times to construct a three-dimensional article. It can include...

[0064] The resulting three-dimensional article can then be converted into a sintered article using any of the techniques described elsewhere in this specification.

[0065] The curing step can be carried out by any suitable means (which may depend on components present in the composition, particularly curable (meth)acrylate resin components), but in certain embodiments of the present invention, curing is achieved by exposing the layer to be cured to an effective amount of radiation (e.g., electron beam radiation, UV radiation, visible light, etc.).

[0066] Therefore, in various embodiments, the present invention involves the following steps, namely, a) A step of applying a first layer of a liquid composition according to the present invention to a surface, b) Exposing the first layer to a chemical beam in an image-like manner to form a first exposed image cross section, wherein the radiation has sufficient intensity and duration to cause at least partial curing (e.g., at least 25%, at least 50%, at least 80%, or at least 90%) of the curable (meth)acrylate resin components present in the layer within the exposed area. c) The step of applying an additional layer of the composition onto a pre-exposed photographic cross section. d) Exposing an additional layer to chemical radiation in an image-like manner to form an additional imaging section, wherein the radiation has sufficient strength and duration to cause at least partial curing (e.g., at least 30%, at least 50%, at least 80%, or at least 90%) of the curable (meth)acrylate resin component present in the additional layer in the exposed area, and to cause adhesion of the additional layer to the previously exposed imaging section. e) A step to construct a three-dimensional article by repeating steps c) and d) a desired number of times. This provides a method that includes [something].

[0067] An intermediate article produced by curing the curable (meth)acrylate resin component of the composition (for example, a three-dimensional article obtained by any of the above procedures) is subjected to the removal of at least a portion of the matrix formed by the curing of the curable (meth)acrylate resin component and exposed to conditions effective for sintering sinterable thermoplastic particles, thereby fusing the sinterable thermoplastic particles to form a sintered article.

[0068] In one embodiment of the present invention, the intermediate article is heated to a temperature effective in causing at least partial decomposition of the cured matrix produced from the curable (meth)acrylate resin component. However, such a temperature should be selected to avoid significant decomposition of the calcinable thermoplastic particles. That is, the curable (meth)acrylate resin component is formulated to decompose at a temperature lower than the decomposition temperature of the thermoplastic particles once cured. Providing an oxidizing agent and / or decomposition catalyst during the processing of the intermediate article can help accelerate the decomposition rate of the matrix cured at a given temperature, or help allow decomposition to proceed at a lower temperature than would be possible in the absence of such an oxidizing agent or decomposition catalyst. For example, the intermediate article may be heated in an atmosphere consisting of oxygen. Alternatively, the rate of oxidation or decomposition can be further increased by circulating or removing air from the heating chamber. The curable (meth)acrylate resin component may contain one or more metal species that can promote the decomposition of the cured matrix obtained from the curable (meth)acrylate resin component.

[0069] According to certain embodiments of the present invention, the decomposition temperature of the cured matrix obtained from the curable (meth)acrylate resin composition is lower than the decomposition temperature of the sinterable thermoplastic particles. As used herein, “decomposition temperature” means the temperature at which a 10 mg sample of the material (e.g., cured matrix or sinterable thermoplastic particles) exhibits a 50% decrease in initial weight, as measured by thermogravimetric analysis (TGA) (heating in an air atmosphere with the temperature increased at a rate of 10°C / min). In preferred embodiments, the decomposition temperature of the cured matrix of the curable (meth)acrylate resin composition is lower than the Tm (melting point) of the sinterable thermoplastic particles (if the thermoplastic material is semi-crystalline or crystalline) or the Tg (glass transition temperature) of the sinterable thermoplastic particles (if the thermoplastic material is amorphous), preferably at least 25°C or at least 50°C lower.

[0070] Generally speaking, the decomposition of a hardened matrix produces decomposition products having a molecular weight lower than that of the hardened matrix. In one embodiment, at least a portion of the hardened matrix is ​​volatile enough to exist as a gas under the conditions used to decompose the hardened matrix, and is thus converted into decomposition products that facilitate their removal from the intermediate article. In another embodiment, the decomposition products are sufficiently soluble in a solvent (e.g., an organic solvent) so that they can be washed away or eluted from the intermediate or sintered article by contacting the intermediate or sintered article with the solvent. The solvent should be selected so as not to be a solvent for thermoplastic particles (i.e., thermoplastic particles do not dissolve to a significant degree in the solvent). The solvent may be heated while in contact with the intermediate or sintered article to facilitate the removal of soluble decomposition products.

[0071] The sintering of thermoplastic particles in an intermediate article or during the conversion of a composition into an intermediate article may be carried out under conditions effective in fusing the thermoplastic particles together (which may have residual (meth)acrylate resin components in a hardened form and / or decomposition products generated therefrom on at least a portion of the surface of the thermoplastic particles) while avoiding complete melting of the thermoplastic particles. For example, the intermediate article may be heated to a temperature up to 25°C lower than the melting point of the thermoplastic particles. In one embodiment, such heating may be carried out in a mold in which the intermediate article is placed. The intermediate article may be subjected to compression, for example, within the mold during such heating. For example, a sintered article can be manufactured by fusing the sinterable thermoplastic particles contained in the intermediate article under high temperature and pressure conditions. When heated, the thermoplastic particles contained in the intermediate article may fuse at contact points, forming a solid (which may be porous in certain embodiments). According to certain embodiments, the thermoplastic particles retain their shape except for slight softening at contact points where fusing occurs as the temperature decreases from high to near ambient levels.

[0072] According to certain embodiments, sintering can be performed by bringing an object to a suitable sintering temperature, holding it for a certain period of time, and then slowly cooling it (allowing the thermoplastic material to recrystallize if it has at least partially crystallized or completely solidified). The sintering temperature is generally related to the melting point of the thermoplastic material, but can be below, at the same as, or slightly above the melting point of the thermoplastic material, depending on the material, flow rate, crystallization temperature, and other factors. In this invention, laser sintering techniques, as known, can be used.

[0073] Various non-limiting aspects of the present invention can be summarized as follows:

[0074] Embodiment 1: A composition comprising, essentially consisting of, or comprising sinterable thermoplastic particles and a curable (meth)acrylate resin component, wherein the sinterable thermoplastic particles are insoluble in the curable (meth)acrylate resin component at 25°C.

[0075] Embodiment 2: The composition according to Embodiment 1, wherein the sinterable thermoplastic particles are composed of, essentially composed of, or consist of at least one thermoplastic material selected from the group consisting of polyarylether ketones, polyamides, polyimides, polycarbonates, and fluoropolymers.

[0076] Embodiment 3: The composition according to Embodiment 1, wherein the sinterable thermoplastic particles have a melting point above 250°C, a glass transition temperature above 200°C, or a melting point above 250°C and a glass transition temperature above 200°C.

[0077] Embodiment 4: The composition according to Embodiment 3, wherein the sinterable thermoplastic particles are composed of, essentially composed of, or consist of at least one thermoplastic material selected from the group consisting of polyether ether ketone, polyether ketone ketone, and polyimide.

[0078] Embodiment 5: The composition according to Embodiment 1, wherein the sinterable thermoplastic particles have a melting point above 150°C, a glass transition temperature above 100°C, or a melting point above 150°C and a glass transition temperature above 100°C.

[0079] Embodiment 6: The composition according to Embodiment 5, wherein the sinterable thermoplastic particles comprise at least one thermoplastic material selected from the group consisting of polyamide, polyvinylidene fluoride, and polycarbonate.

[0080] Embodiment 7: The composition according to any one of Embodiments 1 to 6, wherein the sinterable thermoplastic particles have a volume median diameter (Dv50) of 10 to 100 microns as measured by a scanning electron microscope when dry.

[0081] Embodiment 8: The composition according to any one of Embodiments 1 to 7, wherein the curable (meth)acrylate resin component is photocurable.

[0082] Embodiment 9: The composition according to any one of Embodiments 1 to 8, wherein the curable (meth)acrylate resin component is composed of, essentially composed of, or consists of one or more (meth)acrylate functionalized monomers or oligomers.

[0083] Embodiment 10: The composition according to any one of Embodiments 1 to 9, wherein the curable (meth)acrylate resin component is composed of, essentially composed of, or consists of one or more (meth)acrylate functionalized monomers or oligomers containing one or more polyoxyalkylene segments.

[0084] Embodiment 11: The composition according to any one of Embodiments 1 to 10, wherein the curable (meth)acrylate resin component is composed of, essentially composed of, or consists of one or more (meth)acrylate functionalized monomers or oligomers containing one or more polyoxyethylene, polyoxypropylene, or polyoxyethylene / oxypropylene segments.

[0085] Embodiment 12: The composition according to any one of Embodiments 1 to 11, wherein the curable (meth)acrylate resin component is composed of, essentially composed of, or consists of one or more (meth)acrylate-functionalized monomers or oligomers selected from the group consisting of alkoxypolyethylene glycol mono(meth)acrylate, alkoxypolypropylene glycol mono(meth)acrylate, polyethylene glycol di(meth)acrylate, alkoxylated bis-phenol di(meth)acrylate, and alkoxylated aliphatic polyalcohol (meth)acrylate.

[0086] Embodiment 13: The composition according to any one of Embodiments 1 to 12, wherein the curable (meth)acrylate resin component has a viscosity of less than 1500 centipoise at 25°C.

[0087] Embodiment 14: The composition according to any one of Embodiments 1 to 13, wherein the curable (meth)acrylate resin component has a viscosity of less than 800 centipoise at 25°C.

[0088] Embodiment 15: The composition according to any one of Embodiments 8 to 12, wherein the curable (meth)acrylate resin component further comprises at least one photoinitiator.

[0089] Embodiment 16: The composition according to any one of Embodiments 1 to 15, wherein the curable (meth)acrylate resin component is a homogeneous liquid at 25°C.

[0090] Embodiment 17: The composition according to any one of Embodiments 1 to 16, wherein the curable (meth)acrylate resin component, when cured, has a decomposition temperature lower than the melting point of the sinterable thermoplastic particles, or, if the sinterable thermoplastic particles do not have a melting point, a decomposition temperature lower than the glass transition temperature of the sinterable thermoplastic particles.

[0091] Embodiment 18: The composition according to any one of Embodiments 1 to 17, wherein the composition comprises 25 to 60% by weight of sinterable thermoplastic particles and 40 to 75% by weight of a curable (meth)acrylate resin component, based on the total weight of the sinterable thermoplastic particles and the curable (meth)acrylate resin component.

[0092] Embodiment 19: A method for forming a sintered article, namely, a) A composition according to any of embodiments 1 to 18 is cured to form an intermediate article consisting of sinterable thermoplastic particles bonded by a matrix of curable (meth)acrylate resin components in the cured form, and b) Removing at least a portion of the matrix from the intermediate article and exposing it to conditions effective for sintering sinterable thermoplastic particles, thereby fusing the sinterable thermoplastic particles to form a sintered article. Methods that include...

[0093] Embodiment 20: The method according to Embodiment 19, wherein the curing in step a) is performed by irradiating the curable (meth)acrylate resin component with radiation.

[0094] Embodiment 21: The method according to Embodiment 19 or 20, wherein the conditions in step b) include heating the intermediate article at a temperature effective to at least partially decompose the curable (meth)acrylate resin composition in a cured form while avoiding the decomposition of the sinterable thermoplastic particles.

[0095] Embodiment 22: The method according to Embodiment 21, wherein, after heating the intermediate article, the intermediate is brought into contact with a solvent effective in removing at least a portion of the decomposition products of a curable (meth)acrylate resin composition in a cured form.

[0096] Embodiment 23: The method according to any one of Embodiments 19 to 22, wherein the condition in step b) includes compressing the intermediate article.

[0097] Embodiment 24: The method according to any one of Embodiments 19 to 23, wherein the condition in step b) includes exposing the intermediate article to a laser beam.

[0098] Embodiment 25: The method according to any one of Embodiments 19 to 24, wherein the method includes three-dimensional printing.

[0099] Embodiment 26: The method according to any one of embodiments 19 to 25, wherein in step b), at least a portion of the matrix is ​​removed and sinterable thermoplastic particles are sintered simultaneously.

[0100] Embodiment 27: The method according to any one of embodiments 19 to 26, wherein in step b), the removal of at least a portion of the matrix is ​​performed before sintering of the sinterable thermoplastic particles.

[0101] Embodiment 28: The method according to any one of Embodiments 19 to 27, wherein the sintered article is thermoplastic.

[0102] Embodiment 29: A method for producing a sintered article, which is as follows: a) Apply a first layer of the composition according to any of embodiments 1 to 18 onto the surface, b) The first layer is cured to provide a cured first layer, c) Apply a second layer of the composition onto the cured first layer. d) A cured second layer is provided, which is bonded to the cured first layer by curing the second layer. e) Repeat steps c) and d) a desired number of times to construct a three-dimensional article composed of sinterable thermoplastic particles bonded together by a matrix of curable (meth)acrylate resin components in a cured form, and f) Removing at least a portion of the matrix from a three-dimensional article and exposing it to conditions effective for sintering sinterable thermoplastic particles, thereby fusing the sinterable thermoplastic particles to form a sintered article. Methods that include...

[0103] Embodiment 30: A method for producing a three-dimensional printed article using digital light projection, stereolithography, or multi-jet printing, comprising irradiating each layer with a composition according to any one of Embodiments 1 to 18 to form a three-dimensional printed article.

[0104] While the embodiments described herein are presented in a manner that enables the writing of a clear and concise specification, it is intended and recognized that the embodiments can be combined and separated in various ways without departing from the present invention. For example, it is recognized that all preferred features described herein are applicable to all embodiments of the present invention described herein.

[0105] In some embodiments, the inventions herein can be interpreted as excluding any elements or method steps that do not substantially affect the fundamental and novel characteristics of the composition or the method of using the composition. Furthermore, in some embodiments, the inventions herein can be interpreted as excluding any elements or method steps that are not expressly specified herein.

[0106] While the present invention is shown and described herein with reference to specific embodiments, it is not intended to be limited to the details shown. Rather, various modifications can be made without departing from the invention in the details within the scope and scope of the equivalents of the claims. [Examples]

[0107] [Example 1] 35 parts by weight (pbw) of polyether ketone (PEKK) powder (T:I ratio = 70:30, Dv50 = 60 microns) was added to 65 pbw of polyethylene glycol dimethyl acid (SR 210A, Sartomer) along with 1 pbw of photoinitiator. The resulting composition was bulk cured to a thickness of approximately 1 cm on a petri dish. The cured sample pieces were crushed, weighed, and then placed in a 300°C oven for 4 hours. The sample was removed from the oven and weighed again. The mass of the heated sample was only 50% of the original mass. This means that the heat-treated sample contained approximately 30% by weight of the cured matrix derived from polyethylene glycol dimethacrylate and approximately 70% of PEKK (i.e., the majority of the cured matrix derived from polyethylene glycol dimethacrylate was removed as a result of the oven heating step).

[0108] [Example 2] 35 parts by weight (pbw) of polyether ketone (PEKK) powder (T:I ratio = 70:30, Dv50 = 60 microns) is added to 65 pbw of polyethylene glycol dimethacrylate (SR 210A, manufactured by Sartomer) together with 1 pbw of a photoinitiator and a PEKK-compatible surfactant. Using the above composition, a small section (2 cm × 1 cm × 0.5 cm) is printed on an Ember 3D printer. The 3D printed section is weighed and placed in an oven at 325°C for 4 hours. A large portion of the cured matrix derived from the polyethylene glycol dimethacrylate is expected to be lost (due to decomposition and volatilization), leaving a portion containing more than 80% by weight of PEKK.

Claims

1. A method for forming a sintered article, namely, a) A composition comprising sinterable thermoplastic particles and a curable (meth)acrylate resin component that can be formed into a coherently bonded mass by heating and / or compressing without melting until complete liquefaction, wherein the sinterable thermoplastic particles are formed by curing a composition insoluble in the curable (meth)acrylate resin component at 25°C to form an intermediate article composed of sinterable thermoplastic particles bonded by a matrix of the cured curable (meth)acrylate resin component, and b) Removing at least a portion of the matrix from the intermediate article and exposing it to conditions effective for sintering sinterable thermoplastic particles, thereby fusing the sinterable thermoplastic particles to form a sintered article. Methods that include...

2. The method according to claim 1, wherein the sinterable thermoplastic particles are composed of at least one thermoplastic material selected from the group consisting of polyaryletherketone, polyamide, polyimide, polycarbonate, and fluoropolymer.

3. The method according to claim 1, wherein the sinterable thermoplastic particles have a melting point above 250°C, a glass transition temperature above 200°C, or a melting point above 250°C and a glass transition temperature above 200°C.

4. The method according to claim 1, wherein the sinterable thermoplastic particles have a melting point above 150°C, a glass transition temperature above 100°C, or a melting point above 150°C and a glass transition temperature above 100°C.

5. The method according to claim 4, wherein the sinterable thermoplastic particles comprise at least one thermoplastic material selected from the group consisting of polyamide, polyvinylidene fluoride, and polycarbonate.

6. The method according to claim 1, wherein the sinterable thermoplastic particles have a volume median diameter (Dv50) of 10 to 100 microns as measured by a scanning electron microscope when dry.

7. The method according to claim 1, wherein the curable (meth)acrylate resin component is photocurable.

8. The method according to claim 1, wherein the curable (meth)acrylate resin component is composed of one or more (meth)acrylate-functionalized monomers or oligomers.

9. The method according to claim 1, wherein the curable (meth)acrylate resin component is composed of one or more (meth)acrylate-functionalized monomers or oligomers containing one or more polyoxyalkylene segments.

10. The method according to claim 1, wherein the curable (meth)acrylate resin component is composed of one or more (meth)acrylate-functionalized monomers or oligomers containing one or more polyoxyethylene, polyoxypropylene, or polyoxyethylene / oxypropylene segments.

11. The method according to claim 1, wherein the curable (meth)acrylate resin component is composed of one or more (meth)acrylate-functionalized monomers or oligomers selected from the group consisting of alkoxypolyethylene glycol mono(meth)acrylate, alkoxypolypropylene glycol mono(meth)acrylate, polyethylene glycol di(meth)acrylate, alkoxylated bis-phenol di(meth)acrylate, and alkoxylated aliphatic polyalcohol (meth)acrylate.

12. The method according to claim 1, wherein the curable (meth)acrylate resin component has a viscosity of less than 1500 centipoise at 25°C.

13. The method according to claim 1, wherein the curable (meth)acrylate resin component has a viscosity of less than 800 centipoise at 25°C.

14. The method according to claim 1, wherein the curable (meth)acrylate resin component further comprises at least one photoinitiator.

15. The method according to claim 1, wherein the curable (meth)acrylate resin component is a homogeneous liquid at 25°C.

16. The method according to claim 1, wherein the curable (meth)acrylate resin component, when cured, has a decomposition temperature lower than the melting point of the sinterable thermoplastic particles, or, if the sinterable thermoplastic particles do not have a melting point, a decomposition temperature lower than the glass transition temperature of the sinterable thermoplastic particles.

17. The method according to claim 1, wherein the composition comprises 25 to 60% by weight of sinterable thermoplastic particles and 40 to 75% by weight of a curable (meth)acrylate resin component, based on the total weight of the sinterable thermoplastic particles and the curable (meth)acrylate resin component.

18. The method according to claim 1, wherein the curing in step a) is performed by irradiating the curable (meth)acrylate resin component with radiation.

19. The method according to claim 1, wherein the conditions in step b) include heating the intermediate article at a temperature effective to at least partially decompose the curable (meth)acrylate resin composition in a cured form while avoiding the decomposition of sinterable thermoplastic particles.

20. The method according to claim 19, wherein, after heating the intermediate article, the intermediate is brought into contact with a solvent effective in removing at least a portion of the decomposition products of a curable (meth)acrylate resin composition in a cured form of the intermediate article.

21. The method according to claim 1, wherein the condition in step b) includes compressing the intermediate article.

22. The method according to claim 1, wherein the condition in step b) includes exposing the intermediate article to a laser beam.

23. The method according to claim 1, wherein the method includes three-dimensional printing.

24. The method according to claim 1, wherein in step b), at least a portion of the matrix is ​​removed and sinterable thermoplastic particles are sintered simultaneously.

25. The method according to claim 1, wherein in step b), at least a portion of the matrix is ​​removed before sintering the sinterable thermoplastic particles.

26. The method according to claim 1, wherein the sintered article is thermoplastic.

27. A method for producing a sintered article, namely, a) A composition comprising sinterable thermoplastic particles and a curable (meth)acrylate resin component, which can be formed into a coherently bonded mass by heating and / or compressing without melting until complete liquefaction, wherein the sinterable thermoplastic particles are coated on the surface with a first layer of the composition which is insoluble in the curable (meth)acrylate resin component at 25°C. b) The first layer is cured to provide a cured first layer. c) Apply a second layer of the composition onto the cured first layer. d) A cured second layer is provided, which is bonded to the cured first layer by curing the second layer. e) Repeat steps c) and d) a desired number of times to construct a three-dimensional article composed of sinterable thermoplastic particles bonded together by a matrix of curable (meth)acrylate resin components in a cured form, and f) Removing at least a portion of the matrix from a three-dimensional article and exposing it to conditions effective for sintering sinterable thermoplastic particles, thereby fusing the sinterable thermoplastic particles to form a sintered article. Methods that include...

28. A method for creating a three-dimensional print using digital light projection, stereolithography, or multi-jet printing, comprising a composition comprising sinterable thermoplastic particles and a curable (meth)acrylate resin component, which can be formed into a coherently bonded mass by heating and / or compressing without melting until complete liquefaction, wherein the sinterable thermoplastic particles are irradiated layer by layer with a composition insoluble in the curable (meth)acrylate resin component at 25°C to form a three-dimensional print.

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