Transparent material composition for three-dimensional molding and preparation method and application thereof

Abstract

The present application provides a transparent material composition for three-dimensional molding, a preparation method and application thereof, the composition comprising the following components in mass ratio: (meth) acrylate oligomer 0-30%, (meth) acrylate monomer 60-90%, photoinitiator 0.8-8%, auxiliary agent 3-10%; wherein the photoinitiator comprises a first photoinitiator and a second photoinitiator, the ultraviolet absorption wavelength of the first photoinitiator is lower than the ultraviolet absorption wavelength of the second photoinitiator, the first photoinitiator and the second photoinitiator are respectively used to initiate the polymerization reaction of the (meth) acrylate monomer, or respectively to initiate the polymerization reaction of the (meth) acrylate monomer and the (meth) acrylate oligomer. The composition is suitable for 3D printing and can improve the optical consistency and other properties of 3D objects.

Description

Technical Field

[0001] The present invention relates to the technical field of 3D printing, and in particular to a transparent material composition for three-dimensional molding, a preparation method and application thereof. Background Art

[0002] 3D printing technology is called rapid prototyping technology, additive manufacturing technology, etc., and has gradually become the mainstream molding method of three-dimensional objects (3D objects). However, in the related art, due to the poor compatibility of components such as cationic photocurable components and free radical photocurable components contained in the transparent materials used for 3D printing, large differences in curing rates (such as the curing rate of cationic photocurable components is usually lower than the curing rate of free radical photocurable components), and the raw materials with a small amount of color and other influencing factors, the clarity (i.e., transmittance) of 3D objects printed using transparent materials is usually poor, especially the clarity of the entire outer surface of the object is uneven, and the consistency of optical properties is poor. In the prior art, there is an absolute transparent raw material used to manufacture a transparent material composition to improve the clarity and other properties of 3D objects, but this increases the difficulty of preparing transparent materials. At the same time, this type of transparent material is suitable for injection molding technology, but has poor applicability to 3D printing processes and is limited in application. Therefore, there is still an urgent need to solve the technical problems of poor performance such as the clarity and consistency of optical properties of 3D objects. Summary of the invention

[0003] The present application provides a transparent material composition for three-dimensional molding, a preparation method and application thereof. The transparent material composition for three-dimensional molding is suitable for 3D printing, can improve the surface clarity of 3D objects, improve the consistency of optical properties of 3D objects, and effectively overcome the defects of the prior art.

[0004] In one aspect of the present application, a transparent material composition for three-dimensional molding is provided, comprising the following components in a mass ratio: 0-30% of (meth)acrylate oligomers, 60-90% of (meth)acrylate monomers, 0.8-8% of photoinitiators, and 3-10% of auxiliary agents; wherein the photoinitiator comprises a first photoinitiator and a second photoinitiator, the ultraviolet absorption wavelength of the first photoinitiator is lower than the ultraviolet absorption wavelength of the second photoinitiator, and the first photoinitiator and the second photoinitiator are respectively used to initiate a polymerization reaction of the (meth)acrylate monomers, or are respectively used to initiate a polymerization reaction of the (meth)acrylate monomers and the (meth)acrylate oligomers.

[0005] Optionally, the ultraviolet absorption wavelength of the first photoinitiator is 200-280 nm, and / or the ultraviolet absorption wavelength of the second photoinitiator is 330-410 nm.

[0006] Optionally, the first photoinitiator and the second photoinitiator are free radical initiators respectively.

[0007] Optionally, the first photoinitiator is selected from one or more of benzoin dimethyl ether, 2-methyl-2-(4-morpholinyl)-1-[4-(methylthio)phenyl]-1-propanone, dibenzophenone, benzil dimethyl ketal, 2-phenylbenzyl-2-dimethylamine-1-(4-morpholinobenzylphenyl)butanone, 2-hydroxy-methylphenylpropane-1-one, and 1-hydroxy-cyclohexyl-phenyl ketone; and / or, the second photoinitiator is selected from one or more of 2,4,6-trimethylbenzoyl-1-one, 2,4,6-trimethylbenzoylphosphineethyl ester, and phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide.

[0008] Optionally, in the photoinitiator, the mass ratio of the first photoinitiator is 10-40%, and the remainder is the second photoinitiator.

[0009] Optionally, the (meth)acrylate monomer contains a benzene ring structure.

[0010] Optionally, the (meth)acrylate monomer includes a monofunctional (meth)acrylate monomer containing a benzene ring structure and / or a multifunctional (meth)acrylate monomer containing a benzene ring structure.

[0011] Optionally, the monofunctional (meth)acrylate monomer containing a benzene ring structure is selected from at least one of benzyl acrylate, o-phenylphenoxyethyl acrylate, ethoxyphenol acrylate, 2-(p-isopropylphenyl-phenoxy)-ethyl acrylate, nonylphenol propoxy acrylate, phenoxyethyl methacrylate, benzyl methacrylate, ethoxyphenol methacrylate, and 2-(p-isopropylphenyl-phenoxy)-ethyl methacrylate; the multifunctional (meth)acrylate monomer containing a benzene ring structure is selected from at least one of ethoxylated bisphenol A diacrylate containing 1-40 ethoxy groups, ethoxylated bisphenol F acrylate resin containing 1-40 ethoxy groups, and ethoxylated bisphenol A dimethacrylate containing 1-40 ethoxy groups.

[0012] Optionally, the (meth)acrylate monomers include methacrylate monomers and acrylate monomers; in the (meth)acrylate monomers, the mass ratio of the methacrylate monomers is 30-70%, and the remainder is the acrylate monomers.

[0013] Optionally, the auxiliary agent includes at least one of a stabilizer, a leveling agent, and a defoaming agent.

[0014] Optionally, the stabilizer includes a hindered amine stabilizer.

[0015] Optionally, in the transparent material composition for three-dimensional molding, the mass ratio of the stabilizer is 2-5%, and / or the mass ratio of the leveling agent is 0.4-4%, and the mass ratio of the defoaming agent is 0.4-2.5%.

[0016] Optionally, the transparent material composition for three-dimensional molding has a viscosity of 30-90 cP at room temperature, a viscosity of 6-16 cP at 40-60° C., and a surface tension of 15-35 mN / m at 40-60° C.

[0017] Another aspect of the present application provides a method for preparing the above-mentioned transparent material composition for three-dimensional molding, comprising: mixing the (meth)acrylate oligomer, (meth)acrylate monomer, and auxiliary agent to obtain a first mixture; dissolving the photoinitiator in the first mixture to obtain a second mixture; filtering the second mixture, collecting the filtrate, and obtaining the transparent material composition for three-dimensional molding.

[0018] In another aspect of the present application, a three-dimensional object forming method is provided, comprising: using the above-mentioned transparent material composition for three-dimensional forming or the transparent material composition for three-dimensional forming obtained by the above-mentioned preparation method to perform printing and forming to obtain a three-dimensional object.

[0019] Optionally, the printing and molding process includes: S1, forming a transparent material layer from the transparent material composition for three-dimensional molding; S2, sequentially providing a first radiation and a second radiation to the transparent material layer to form a layer of a three-dimensional object; wherein the first radiation is ultraviolet light absorbed by the first photoinitiator, and the second radiation is ultraviolet light absorbed by the second photoinitiator; S3, repeating steps S1 to S2 to stack the obtained layers of multiple three-dimensional objects layer by layer to form a three-dimensional object.

[0020] In another aspect of the present application, a three-dimensional object is provided, which is printed from the above-mentioned transparent material composition for three-dimensional molding or the transparent material composition for three-dimensional molding prepared according to the above-mentioned preparation method, or is prepared by the above-mentioned three-dimensional object molding method.

[0021] According to another aspect of the present application, a three-dimensional object forming device is provided for forming the above-mentioned transparent material composition for three-dimensional forming or the transparent material composition for three-dimensional forming prepared according to the above-mentioned preparation method, comprising a supporting platform, a feeding part, a first radiation source and a second radiation source, wherein the feeding part is used to make the transparent material composition for three-dimensional forming form a transparent material layer on the supporting platform; the first radiation source is used to provide a first radiation to the transparent material layer; and the second radiation source is used to provide a second radiation to the transparent material layer.

[0022] In the present application, under the composition system of the transparent material composition for three-dimensional molding, (meth) acrylate oligomers and (meth) acrylate monomers are used as photocurable components, and the initiator can act on the photocurable components under ultraviolet radiation to cure the photocurable components to form a layer of a three-dimensional object, thereby forming a three-dimensional object through 3D printing. Among them, the first photoinitiator and the second photoinitiator have different ultraviolet absorption wavelengths, and can absorb radiation in different ultraviolet bands to be activated, thereby inducing the photocurable components to react and cure to different degrees at different time periods. The ultraviolet absorption wavelength of the first photoinitiator is smaller than the ultraviolet absorption wavelength of the second photoinitiator, so that the photocurable components can be first excited by the first photoinitiator for partial curing, and then excited by the second photoinitiator for further curing, thereby improving the surface clarity of the 3D object formed by 3D printing, making the overall clarity of the 3D object basically consistent, and improving the transmittance, refractive index, consistency of optical properties, glossiness and other properties of the 3D object. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic flow chart of a 3D object forming method according to an embodiment of the present application;

[0024] Figure 2 This is a schematic flow chart of a 3D object forming method according to another embodiment of the present application;

[0025] Figure 3 This is a schematic structural diagram of a 3D object forming device according to an embodiment of the present application;

[0026] Figure 4 This is a schematic structural diagram of a 3D object forming device according to another embodiment of the present application.

[0027] Explanation of the accompanying drawings: 1: container; 2: ink tube; 3: print head; 4: carriage; 5: body; 6: composition; 7: support platform; 8: transparent material layer; 9: first radiation source; 10: second radiation source; 11: leveling component; 12: controller; 13: lifting component; S100, S200, S210, S300, S400: steps. DETAILED DESCRIPTION

[0028] In order to solve the technical problems of poor performance such as clarity and consistency of optical properties of 3D objects, the embodiment of the present application provides a transparent material composition for three-dimensional molding, including the following components in the following mass ratios: 0-30% of (meth)acrylate oligomers, 60-90% of (meth)acrylate monomers, 0.8-8% of photoinitiators, and 3-10% of auxiliary agents; wherein the photoinitiator includes a first photoinitiator and a second photoinitiator, and the wavelength of ultraviolet absorption light (first radiation) of the first photoinitiator is lower than the wavelength of ultraviolet absorption light (first radiation) of the second photoinitiator; the first photoinitiator and the second photoinitiator are respectively used to initiate curing (i.e., polymerization reaction) of the (meth)acrylate monomers, or are respectively used to initiate curing of the (meth)acrylate monomers and the (meth)acrylate oligomers.

[0029] Specifically, when the mass ratio of the above-mentioned (meth)acrylate oligomer is 0, the first photoinitiator and the second photoinitiator act on the (meth)acrylate monomers respectively, so that they are cured to different degrees at different time periods. When the mass ratio of the acrylate oligomer is greater than 0, the first photoinitiator and the second photoinitiator act on the mixed system containing the (meth)acrylate monomers and the (meth)acrylate oligomers respectively, so that they are cured to different degrees at different time periods. Thus, the first photoinitiator and the second photoinitiator act on the same photocurable component (i.e., the (meth)acrylate monomers, or the mixed system of the (meth)acrylate monomers and the (meth)acrylate oligomers), triggering the polymerization reaction of the photocurable component at different time periods, and curing to different degrees, which can improve the clarity and other properties of the 3D object.

[0030] Specifically, the above-mentioned transparent material composition is suitable for 3D printing processes, such as stereolithography (SLA) process, 3D inkjet printing process, etc., and can improve the transmittance, refractive index, optical performance consistency, glossiness and other properties of 3D objects formed by 3D printing. The reason for this is that at least the first photoinitiator and the second photoinitiator act on the same photocurable component, and the ultraviolet absorption wavelength of the first photoinitiator is lower than that of the second photoinitiator, so that the photocurable component can be partially cured by the first photoinitiator first, and then further cured by the second photoinitiator, which is beneficial to the material uniformity of the cured product; at the same time, the photocurable component is partially cured by the first photoinitiator, which can reduce the fluidity of the composition, so as to reduce the fluidity of the ink droplets during 3D inkjet printing and improve the accuracy of the ink droplet landing point, and then it is further cured by the second photoinitiator, which effectively improves the transmittance, refractive index, optical consistency, glossiness and other properties of the 3D object. In addition, the above composition has good fluidity during the 3D printing process, is suitable for 3D inkjet printing technology, and can also extend the service life of the print head (feeding part), which is beneficial to practical industrial applications.

[0031] Specifically, the first photoinitiator and the second photoinitiator are free radical photoinitiators respectively. When the ultraviolet absorbing light of the first photoinitiator is provided to the above-mentioned composition, the first photoinitiator absorbs the first radiation and generates free radicals, and the free radicals trigger the photocurable component to undergo a curing reaction / polymerization reaction to achieve partial curing; when the ultraviolet absorbing light of the second photoinitiator is provided to the above-mentioned composition, the second photoinitiator absorbs the second radiation and generates free radicals, which trigger the partially cured photocurable component to further cure.

[0032] In addition, the ultraviolet absorption wavelength of the first photoinitiator (ultraviolet light initiation wavelength / ultraviolet radiation wavelength of the first radiation) is 200-280nm, for example, 200nm, 210nm, 220nm, 230nm, 240nm, 250nm, 260nm, 270nm, 280nm or a range composed of any two thereof, and the ultraviolet absorption wavelength of the second photoinitiator (ultraviolet light initiation wavelength / ultraviolet radiation wavelength of the second radiation) is 330-410nm, for example, 330nm, 350nm, 370nm, 390nm, 400nm, 410nm or a range composed of any two thereof, which is beneficial to further improve the transmittance, optical consistency and other properties of the 3D object.

[0033] Studies have shown that during 3D inkjet printing, when the ejected composition is irradiated with ultraviolet light having a wavelength of 200-280nm, the composition will generally be partially cured immediately, and the degree of curing may be, for example, about 20-30%. At this degree of curing, the lateral flow of ink droplets can be suppressed, thereby improving the accuracy of ink droplet landing points; when the partially cured composition is irradiated with ultraviolet light having a wavelength of 330-410nm, the composition is further cured, and the degree of curing may be, for example, about 50-90%, thereby improving the supporting strength of the cured product (layer of the 3D object) and improving the bonding strength between the layer currently formed by curing and the layer formed by the previous curing, thereby improving the bonding strength between the layers of the 3D object and improving the transmittance, optical consistency and other properties of the 3D object in the direction of layer stacking.

[0034] In some specific embodiments, the first photoinitiator is selected from one or more of benzoin dimethyl ether, 2-methyl-2-(4-morpholinyl)-1-[4-(methylthio)phenyl]-1-propanone, benzophenone, benzil dimethyl ketal, 2-phenylbenzyl-2-dimethylamine-1-(4-morpholinobenzylphenyl)butanone, 2-hydroxy-methylphenylpropane-1-one, and 1-hydroxy-cyclohexyl-phenyl ketone.

[0035] In some specific embodiments, the second photoinitiator is selected from one or more of 2,4,6-trimethylbenzoyl-1-one, 2,4,6-trimethylbenzoylphosphine ethyl ester, and phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide.

[0036] Further research has shown that during the 3D inkjet printing process, when the content of the first photoinitiator in the photoinitiator is too little (less than 10%), the curing rate of the composition is too low, resulting in lateral flow of ink droplets and inaccurate ink droplet landing points, affecting the optical consistency and other properties of the 3D object; when the content of the first photoinitiator in the photoinitiator is too high (higher than 40%), the curing rate of the composition is too fast, and it is easy to be cured immediately and the degree of curing is too large, or even completely cured, resulting in poor adhesion between the formed layer and the layer formed by the next curing, which will also affect the transmittance and other properties of the 3D object in the stacking direction.

[0037] Therefore, taking the above factors into consideration, in some preferred embodiments, in the above-mentioned photoinitiator, the mass ratio of the first photoinitiator (i.e., the ratio of the mass of the first photoinitiator to the total mass of the photoinitiator) can be 10-40%, for example, 10%, 15%, 20%, 25%, 30%, 35%, 40%, etc., and the remainder is the second photoinitiator, that is, the mass ratio of the second photoinitiator is 60-90%, for example, 60%, 65%, 70%, 75%, 80%, 85%, 90%, etc., so that the above-mentioned composition has more suitable parameters such as curing rate and curing degree at different time periods in the 3D printing process, thereby further optimizing the transmittance, optical consistency and other properties of the 3D object.

[0038] In addition, in the above composition, the mass ratio of the photoinitiator (0.8-8%) is the ratio of the mass of the photoinitiator to the total mass of the composition. When the photoinitiator is composed of a first initiator and a second initiator, the mass ratio of the photoinitiator is equal to the ratio of the sum of the mass of the first initiator and the mass of the second initiator to the total mass of the composition. Exemplarily, the mass ratio of the photoinitiator is, for example, 0.8%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, etc.

[0039] Specifically, in the above-mentioned composition, a (meth)acrylate monomer is used as a photocurable component, or a mixed system of a (meth)acrylate oligomer and a (meth)acrylate monomer is used as a photocurable component, and a photoinitiator is used to initiate a photocuring reaction of the photocurable component, thereby achieving curing. As described above, the composition of the embodiment of the present application is suitable for 3D printing. During the 3D printing process, ultraviolet radiation of different wavelengths can be applied at different time periods, thereby activating the first photoinitiator and the second photoinitiator at different time periods, so that the composition is cured in different time periods, extending the overall curing time of the composition, improving the accuracy of the ink droplet landing point of the composition, and the uniformity of the cured product and other properties, thereby improving the transmittance, optical consistency and other properties of the printed 3D object.

[0040] In the above composition, the mass ratio (60-90%) of the (meth)acrylate monomers refers to the ratio of the mass of the (meth)acrylate monomers to the total mass of the composition, that is, when there are multiple (meth)acrylate monomers, the mass ratio (60-90%) of the (meth)acrylate monomers refers to the ratio of the sum of the masses of these (meth)acrylate monomers to the total mass of the composition. Exemplarily, in the above composition, the mass ratio of the (meth)acrylate monomers is, for example, 60%, 65%, 70%, 75%, 80%, 85%, 90%, etc.

[0041] In the above composition, the mass ratio (0-30%) of the (meth)acrylate oligomer refers to the ratio of the mass of the (meth)acrylate oligomer to the total mass of the composition, that is, when there are multiple (meth)acrylate oligomers, the mass ratio (0-30%) of the (meth)acrylate oligomer refers to the ratio of the sum of the masses of these (meth)acrylate oligomers to the total mass of the composition. Exemplarily, in the above composition, the mass ratio of the (meth)acrylate oligomer is, for example, 0, 1%, 5%, 10%, 15%, 20%, 25%, 30%, etc.

[0042] Among them, when the mass ratio of the (meth)acrylate oligomer is 0, that is, the composition does not contain the (meth)acrylate oligomer, the first photoinitiator and the second photoinitiator are respectively used to initiate the (meth)acrylate monomer to undergo a photocuring reaction / polymerization reaction; when the mass ratio of the (meth)acrylate oligomer is greater than 0, that is, the composition contains the (meth)acrylate oligomer and the (meth)acrylate monomer, the first photoinitiator and the second photoinitiator are respectively used to initiate the (meth)acrylate oligomer and the (meth)acrylate monomer to undergo a photocuring reaction.

[0043] According to the research of the present application, it is generally preferred that the mass ratio of (meth)acrylate oligomers is greater than 0. In this way, during the photocuring reaction, (meth)acrylate monomers and (meth)acrylate oligomers can undergo graft copolymerization to form cross-linked polymers, which can improve the mechanical strength of the cured product / polymer and further optimize the performance of the 3D object.

[0044] Generally, the (meth)acrylate oligomers include methacrylate oligomers and / or acrylate oligomers.

[0045] The (meth)acrylate oligomers can be purchased commercially or prepared in-house, for example, at least one of the following oligomers: MIRAMER PU2100, MIRAMER PU5100, MIRAMER SC2404, MIRAMERMU3603, MIRAMER HR6100, MIRAMER HR6200, UDMA (urethane dimethyl acrylate), etc. from Miwon, CN2920, CN3211, CN8894, CN9007, CN9023, CN9290, CN969 from Sartomer Chemical Co., Ltd. NS, CN991, CN9167, CN9782, CN9783, etc., 6106, 6112-100, 6123, 6127, 6131-1, 6185, etc. of Taiwan Changxing Chemical Co., Ltd., BRC-843D, BRC-4421, BR-952, BR-970BT, BR-970H, BRC-443, etc. of Dymax-Bomar.

[0046] In addition, the (meth)acrylate monomer contains a benzene ring structure, that is, the above-mentioned (meth)acrylate monomer is selected from the (meth)acrylate monomer containing a benzene ring structure, wherein the benzene ring structure is contained, and the monomer has a high refractive index, which can further improve the refractive index, glossiness and other properties of the 3D object.

[0047] Specifically, the (meth)acrylate monomers include one or more of a monofunctional (meth)acrylate monomer containing a benzene ring structure and a multifunctional (meth)acrylate monomer containing a benzene ring structure. The monofunctional group refers to a (meth)acrylate monomer containing one acrylate group, and the multifunctional group refers to a (meth)acrylate monomer containing multiple acrylate groups.

[0048] In some embodiments, the monofunctional (meth)acrylate monomer containing a benzene ring structure is selected from at least one of benzyl acrylate, o-phenylphenoxyethyl acrylate, ethoxyphenol acrylate (such as di(ethoxy)phenol acrylate with two ethoxy groups), 2-(p-isopropylphenyl-phenoxy)-ethyl acrylate, nonylphenol propoxy acrylate, phenoxyethyl methacrylate, benzyl methacrylate, ethoxyphenol methacrylate, 2-(p-isopropylphenyl-phenoxy)-ethyl methacrylate, etc.

[0049] Among them, these monomers can be purchased commercially or homemade, for example, benzyl acrylate can be M1182 from Miwon, EM75 from Taiwan Changxing Chemical Co., Ltd., HN-BZ001 from Zhide Chemical (Shanghai) Co., Ltd., etc.; o-phenylphenoxyethyl acrylate can be M1142 from Miwon, EM2105 from Taiwan Changxing Chemical Co., Ltd., etc.; ethoxyphenol acrylate can be M140 from Miwon, SR339 from Sartomer Chemical Co., Ltd. NS, EM2101 of Taiwan Changxing Chemical Co., Ltd., HN-PHA11, HN-PHA21, HN-PHA41 of Zhide Chemical (Shanghai) Co., Ltd., etc.; 2-(p-isopropylphenyl-phenoxy)-ethyl acrylate can be EM2107 from Taiwan Changxing Chemical Co., Ltd., etc.; nonylphenol propoxy acrylate can be HN-NPF21, HN-NP81, HN-NP41, HN-NP81, etc. from Zhide Chemical (Shanghai) Co., Ltd.; phenoxyethyl methacrylate can be SR340NS from Sartomer Chemical Co., Ltd., EM310 from Taiwan Changxing Chemical Co., Ltd., HN-PHEMA from Zhide Chemical (Shanghai) Co., Ltd., etc.; benzyl methacrylate can be HN-BZ001M from Zhide Chemical (Shanghai) Co., Ltd., EM77 from Taiwan Changxing Chemical Co., Ltd., etc.

[0050] In addition, the multifunctional (meth)acrylate monomer containing a benzene ring structure can specifically include at least one of a difunctional (meth)acrylate monomer containing a benzene ring structure (containing two acrylate groups) and a trifunctional (meth)acrylate monomer containing a benzene ring structure (containing three acrylate groups).

[0051] Specifically, the multifunctional (meth)acrylate monomer containing a benzene ring structure can be selected from at least one of ethoxylated bisphenol A diacrylates with different degrees of ethoxylation, ethoxylated bisphenol F acrylate resins with different degrees of ethoxylation, and ethoxylated bisphenol A dimethacrylates with different degrees of ethoxylation, wherein different degrees of ethoxylation refer to different numbers of ethoxy groups in the monomer molecular structure, and the number of ethoxy groups can be 1-40, for example, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, etc.

[0052] Generally, when the above-mentioned bisphenol resin (i.e., ethoxylated bisphenol A diacrylate, ethoxylated bisphenol F acrylate resin, or ethoxylated bisphenol A dimethacrylate) has n ethoxy groups, the n ethoxy groups are substantially symmetrically distributed on the substituents of the two benzene rings of the bisphenol resin, so that the bisphenol resin has a relatively symmetrical structure, that is, when n is an even number, there are n / 2 ethoxy groups on the substituents of the two benzene rings of the bisphenol resin, and when n is an odd number, there are (n-1) / 2 ethoxy groups on one of the substituents of the two benzene rings of the bisphenol resin, and (n+1) / 2 ethoxy groups on the other. These bisphenol resins can be purchased commercially or prepared by conventional methods in the art, and this application does not impose any particular restrictions on this.

[0053] Preferably, the multifunctional (meth)acrylate monomer containing a benzene ring structure is selected from at least one of ethoxylated bisphenol A diacrylate containing 1-40 ethoxy groups, ethoxylated bisphenol F acrylate resin containing 1-40 ethoxy groups, and ethoxylated bisphenol A dimethacrylate containing 1-40 ethoxy groups.

[0054] For example, the ethoxylated bisphenol A diacrylate includes, for example, 10-ethoxy bisphenol A diacrylate having 10 ethoxy groups, and the ethoxylated bisphenol A dimethacrylate includes, for example, tetraethoxylated bisphenol A dimethacrylate having four ethoxy groups.

[0055] The multifunctional (meth)acrylate monomers can be purchased commercially or prepared in-house. For example, the ethoxylated bisphenol A diacrylates with different ethoxylation degrees are selected from at least one of the following monomers: M240, M244, M2100, M2200 of Meiyuan, SR349NS of Sartomer, EM2260, EM2261, EM2263, EM2265, EM2269 of Changxing, HN-BP32, HN-BP42, HN-BP102, HN-BP202, HN-BP302 of Zhide Chemical, etc.; the ethoxylated bisphenol A dimethacrylates with different ethoxylation degrees are selected from at least one of the following monomers: M241, M245, M2101, M2301 of Meiyuan, SR101, SR150, SR348OP of Sartomer NS, SR541, Changxing's EM3260, EM3261, EM3262, EM3265, Zhide Chemical's HN-BPM32, HN-BPM102, HN-BPM302, HN-BPM172, etc.; the above-mentioned ethoxylated bisphenol F acrylate resins with different degrees of ethoxylation are, for example, M290 from Meiyuan.

[0056] Generally, the above-mentioned (meth)acrylate monomers include methacrylate monomers and / or acrylate monomers, wherein the acrylate monomers are, for example, selected from at least one of the above-mentioned benzyl acrylate, o-phenylphenoxyethyl acrylate, ethoxyphenol acrylate, 2-(p-isopropylphenyl-phenoxy)-ethyl acrylate, nonylphenol propoxy acrylate, ethoxylated bisphenol A diacrylate with different ethoxylation degrees (with two acrylate groups), ethoxylated bisphenol F acrylate resin with different ethoxylation degrees, etc., and the methacrylate monomers are, for example, selected from at least one of the above-mentioned phenoxyethyl methacrylate, benzyl methacrylate, ethoxyphenol methacrylate, 2-(p-isopropylphenyl-phenoxy)-ethyl methacrylate, ethoxylated bisphenol A dimethacrylate with different ethoxylation degrees (with two methacrylate groups, i.e., with two acrylate groups, each acrylate group has a methyl group on its side), etc., which will not be described in detail here.

[0057] In some embodiments, among the above-mentioned (meth)acrylate monomers, the mass ratio of methacrylate monomers (i.e., the ratio of the mass of methacrylate monomers to the sum of the masses of methacrylate monomers and acrylate monomers (i.e., the total mass of the two)) is 30-70%, for example, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, etc., and the remainder is acrylate monomers (i.e., the mass ratio of acrylate monomers is 30-70%).

[0058] The auxiliary agent may include at least one of a stabilizer, a leveling agent, and a defoaming agent.

[0059] The stabilizer is used to absorb the ultraviolet absorption light / first radiation of the first photoinitiator, so that the curing process of the composition is more stable, and the performance of the 3D object is further optimized. Specifically, in the process of applying the first radiation to the composition to partially cure the composition, the stabilizer absorbs part of the first radiation, appropriately prolongs the curing time, and is conducive to further regulating parameters such as the curing rate and degree of curing of the composition, and optimizing the adhesion between the layers in the 3D object and the light transmittance in the stacking direction.

[0060] In some preferred embodiments, in the above-mentioned composition, the mass ratio of the stabilizer (i.e., the ratio of the mass of the stabilizer to the total mass of the composition) is 2-5%, for example, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, etc. When the content of the stabilizer is too low (lower than 2%), its stabilizing effect is limited, for example, it cannot effectively extend the curing time of the composition during the application of the first radiation. However, when the content of the stabilizer is too high (higher than 5%), the first radiation is excessively absorbed, and the composition cannot be immediately solidified into a partially cured state, resulting in lateral flow of ink droplets of the composition sprayed during 3D printing, reducing the accuracy of the ink droplet landing point, and affecting the optical consistency and other properties of the 3D object. Therefore, controlling the mass ratio of the stabilizer within the above-mentioned range is conducive to further optimizing the performance of the 3D object.

[0061] Specifically, the stabilizer includes a hindered amine stabilizer, for example, a highly sterically hindered hindered amine stabilizer, which has strong absorption of the first radiation (for example, ultraviolet absorption light of 200-280 nm).

[0062] The above-mentioned stabilizer can be purchased commercially or prepared by oneself. For example, the hindered amine stabilizer can be selected from at least one of the following reagents: Tinuvin 900, Tinuvin 622LD, Tinuvin 770, Tinuvin 123, Tinuvin P, Tinuvin 626, Tinuvin 292, Tinuvin 400 of BASF, Sanduvor 3050, Sanduvor 3052, Tinuvin-1130 (3-[3-(2-h-benzotriazole-2-yl)-4-hydroxy-5-tert-butylphenyl]-propionic acid-polyethylene glycol 300 ester) of Klein, etc.

[0063] In addition, the defoamer is mainly used to eliminate bubbles generated by the composition during filtering, printing, etc., to prevent the generated bubbles from affecting the smoothness of printing. In the above composition, the mass ratio of the defoamer (i.e., the ratio of the mass of the defoamer to the total mass of the composition) can be 0.4-2.5%, such as 0.4%, 0.8%, 1%, 1.2%, 1.5%, 1.8%, 2%, etc.

[0064] Exemplarily, the defoaming agent can be selected from at least one of the following agents: Efka 7081, Efka7082, etc. from Efka, TEGO Airex 920, TEGO Airex 921, TEGO Foamex 810, TEGOAirex986, TEGO Foamex N, etc. from Digo, BYK055, BYK088, BYK020, BYK025, etc. from BYK.

[0065] In addition, the leveling agent is mainly used to reduce the surface tension of the composition (ink) during 3D printing and improve the leveling of the ink. In the above composition, the mass ratio of the leveling agent (i.e., the ratio of the mass of the leveling agent to the total mass of the composition) can be 0.4-4%, such as 0.4%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, etc.

[0066] Exemplarily, the leveling agent is selected from at least one of the following agents: TEGO wet 270, TEGO wet 500, TEGO RAD 2010, TEGO RAD 2011, TEGO RAD 2100, TEGO RAD 2200, TEGO Glide450, etc. from Tego, BYK 333, BYK 377, BYK1798, BYK-UV3530, BYK-UV3575, BYK-UV3535, etc. from BYK.

[0067] Specifically, in the above composition, the mass ratio of the auxiliary agent (3-10%) refers to the ratio of the mass of the auxiliary agent to the total mass of the composition. When there are multiple auxiliary agents, the mass ratio of the auxiliary agent (3-10%) refers to the ratio of the sum of the masses of these auxiliary agents to the total mass of the composition. For example, the auxiliary agent is composed of the above stabilizer, leveling agent and defoamer, then the mass ratio of the auxiliary agent (3-10%) refers to the sum of the masses of the stabilizer, leveling agent and defoamer to the total mass of the composition. Exemplarily, in the above composition, the mass ratio of the auxiliary agent is 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc.

[0068] Generally, the transparent material composition for three-dimensional molding can be inkjet printed at a relatively low working temperature (such as 40-60°C), and its viscosity at room temperature (such as about 25°C) is 30-90cP, for example, 30cP, 40cP, 50cP, 60cP, 70cP, 80cP, 90cP, etc., and the viscosity at 40-60°C (working temperature) is 6-16cP, for example, 6cP, 8cP, 10cP, 12cP, 14cP, 16cP, etc., and the surface tension at 40-60°C is 15-35mN / m, for example, 15mN / m, 18mN / m, 20mN / m, 22mN / m, 25mN / m, 28mN / m, 30mN / m, 32mN / m, 35mN / m, etc.

[0069] As described above, the use of the above-mentioned composition for 3D printing can improve the transmittance, refractive index, optical consistency, glossiness and other properties of the 3D object. Studies have shown that the 3D object (for example, a 10mm×10mm×10mm cube) printed using the above-mentioned composition has a chromaticity of no more than 100, a transmittance in the horizontal direction of no less than 94%, a transmittance in the stacking direction of no less than 92%, a refractive index in the horizontal direction (the horizontal direction is perpendicular to the stacking direction) of no less than 1.49, and a refractive index in the stacking direction of no less than 1.51.

[0070] In specific implementation, the preparation process of the above-mentioned composition may include: mixing the photocurable components ((meth)acrylate oligomers and (meth)acrylate monomers), photoinitiators (first photoinitiators and second photoinitiators), auxiliary agents and other ingredients according to a ratio to prepare the above-mentioned composition.

[0071] In a preferred embodiment of the present application, the preparation method of the above-mentioned transparent material composition for three-dimensional molding includes: mixing (meth)acrylate oligomers, (meth)acrylate monomers, and additives to obtain a first mixture; dissolving a photoinitiator in the first mixture to obtain a second mixture; filtering the second mixture, collecting the filtrate, and obtaining a transparent material composition for three-dimensional molding.

[0072] Among them, the filtration process may include: subjecting the second mixture to a first-stage filtration through a first filter membrane, and then to a second-stage filtration through a second filter membrane, wherein the pore size of the first-stage filter membrane is larger than the pore size of the second-stage filter membrane. In this way, by filtering in a step-by-step manner, the pore size of the filter membrane of the previous filtration (the first filter membrane) is made larger than the pore size of the filter membrane of the subsequent filtration (the second filter membrane), which can improve the stability of the composition, facilitate the liquefaction and injection of the composition during the 3D printing process, and improve the manufacturing yield of 3D objects.

[0073] In addition, the pore size of the second filter membrane is generally smaller than the pore size of the nozzle of the printing nozzle used for inkjet during the 3D inkjet printing process.

[0074] Among them, the first filter membrane and the second filter membrane are respectively microporous filter membranes, the pore size of the first filter membrane can be specifically 0.4-1μm, for example, 0.4μm, 0.45μm, 0.5μm, 0.6μm, 0.7μm, 0.8μm, 0.9μm, 1μm, etc., and the pore size of the second filter membrane can be specifically 0.2-0.35μm, for example, 0.2μm, 0.22μm, 0.25μm, 0.3μm, 0.35μm, etc.

[0075] Alternatively, the first filter membrane may include a glass fiber membrane, and the second filter membrane may include a polypropylene membrane (PP membrane).

[0076] In addition, the preparation process also includes degassing the filtrate to obtain a transparent material composition for three-dimensional molding. Through the degassing treatment, the fluidity of the composition during use can be optimized, and the printing line breakage caused by the interference of bubbles can be avoided, thereby improving the molding accuracy of the 3D object.

[0077] The degassing time is generally not less than 1 h, and can be specifically 1-3 h, for example, 1 h, 1.5 h, 2 h, 2.5 h, 3 h, etc.

[0078] Specifically, the degassing operation may include one of reduced pressure degassing, normal pressure degassing, and heating degassing. These operation modes can be performed according to conventional procedures in the art and will not be described in detail.

[0079] It is understood that the preparation of the composition is carried out in an environment outside the absorption wavelength range of the photoinitiator to prevent the photoinitiator from being initiated and causing the composition to solidify.

[0080] The composition provided in the embodiment of the present application can be prepared through the above-mentioned mixing, filtering and other steps, and the operation is simple and easy. It can not only form a stable transparent material composition, but also ensure the liquefaction, spraying and other properties of the composition, which is convenient for the use of the composition, and is particularly suitable for 3D printing process.

[0081] One embodiment of the present application also provides a three-dimensional object forming method, comprising: using the above-mentioned transparent material composition for three-dimensional forming or the transparent material composition for three-dimensional forming prepared by the above-mentioned preparation method to perform printing and forming to obtain a three-dimensional object (i.e., a 3D object).

[0082] Specifically, Figure 1 and Figure 2 As shown, the printing and molding process includes: S200, forming a transparent material layer from a transparent material composition for three-dimensional molding; S300, sequentially providing a first radiation and a second radiation to the transparent material layer to form a layer of a 3D object; wherein the first radiation is ultraviolet absorption light of a first photoinitiator, and the second radiation is ultraviolet absorption light of a second photoinitiator; S400, repeating the process of steps S200 to S300, so that the layers of multiple 3D objects formed are stacked layer by layer to form a three-dimensional object, that is, repeatedly forming layers of a 3D object and stacking them layer by layer to form a 3D object.

[0083] Among them, the printing and molding method can specifically be 3D inkjet printing.

[0084] Generally, 3D printing is performed according to 3D object layer printing data. When specifically implemented, the process also includes: S100, obtaining 3D object layer printing data.

[0085] Generally, the model data of the 3D object to be printed can be sliced, layered and processed to obtain layer printing data. The layer printing data is data that characterizes the cross-section of the 3D object. After slicing, layering and data processing of the 3D object, at least one layer of printing data can be obtained. All the layer printing data can be superimposed layer by layer to obtain a digital model of the 3D object. The present application can adopt any conventional method for obtaining layer printing data in the three-dimensional object printing process in the field, and there is no special limitation on this. For example, before printing the 3D object, the model data of the 3D object is obtained, and the data format of the model data is converted, such as converted into STL format, PLY format, WRL format, etc., which can be recognized by slicing software, and the model is sliced ​​and layered using the slicing software to obtain slice layer data, and the slice layer data is processed using a data processor to obtain layer printing data. The layer printing data can specifically include information representing the shape of the object and / or information representing the color of the object.

[0086] In step S200, the composition is sprayed according to the 3D object layer printing data to form a transparent material layer.

[0087] In step S300, the transparent material layer is sequentially provided with a first radiation and a second radiation to cure the transparent material layer to form a layer of a 3D object. Specifically, the ultraviolet radiation wavelength of the first radiation is lower than the ultraviolet radiation wavelength of the second radiation. The first radiation is first applied to the transparent material layer formed by the above composition, and the transparent material layer is irradiated by the first radiation, and the first photoinitiator therein is activated to generate free radicals, and the free radicals trigger the photocurable component to undergo a curing reaction, which is incompletely cured to form a non-flowing partially cured state, thereby preventing the ejected composition ink droplets from flowing laterally and improving the accuracy of the ink droplet landing point; thereafter, the second radiation is applied, and the transparent material layer in a non-flowing state is irradiated by the second radiation, and the second photoinitiator therein is activated to generate free radicals, and the free radicals trigger the photocurable component to further cure (i.e., further trigger the (meth)acrylate monomers, and / or (meth)acrylate oligomers, and copolymers generated by curing these photocurable components during the application of the first radiation, etc. to undergo a polymer reaction), thereby forming a layer of a 3D object (cured product).

[0088] In addition, if Figure 2 As shown, after step S200, the process further includes step S201 of leveling the transparent material layer, and after leveling, step S300 is performed. By leveling the transparent material layer, the excess material on the surface of the transparent material layer can be removed, which is beneficial to the uniformity of the surface of the transparent material layer, improves the accuracy of the transparent material layer, and further improves the accuracy of the 3D object.

[0089] As described above, by irradiating the transparent material layer with different wavelengths in different time periods, the first photoinitiator and the second photoinitiator in the same area of ​​the transparent material layer are activated in different time periods, so that the composition is cured to different degrees in different time periods, which can improve the printing accuracy of the 3D object, and make the layer of the 3D object have good supporting strength, which can support the transparent material layer formed in the subsequent repetition of steps S200 to S300, and have good bonding strength with the layer of the 3D object formed in the subsequent process, thereby improving the transmittance, transparency, refractive index, optical consistency and other properties of the 3D object.

[0090] Therefore, the 3D object provided in the embodiment of the present application is formed by 3D printing of the above-mentioned transparent material composition for three-dimensional molding, and can be specifically obtained by the above-mentioned three-dimensional object molding method. The 3D object has properties such as high light transmittance, high transparency, high refractive index, and uniform optical properties. Studies show that its chromaticity is not greater than (less than or equal to) 100, the light transmittance in the horizontal direction is not less than (greater than or equal to) 94%, the light transmittance in the stacking direction is not less than 92%, the refractive index in the horizontal direction is not less than 1.49, and the refractive index in the stacking direction is not less than 1.51. It can be used as a material for glasses lenses or other optical lens materials with higher refractive index requirements.

[0091] The embodiment of the present application also provides a three-dimensional object molding device for molding the above-mentioned transparent material composition for three-dimensional molding. Specifically, the above-mentioned three-dimensional object molding method can be implemented to mold the above-mentioned composition to make a three-dimensional object.

[0092] In one embodiment, if Figure 3 As shown, the three-dimensional object forming device comprises a supporting platform 7, a feeding part, a first radiation source 9 and a second radiation source 10. The supporting platform 7 is used to carry a transparent material layer 8, the feeding part is used to form a transparent material layer 8 from a transparent material composition 6 for three-dimensional forming on the supporting platform 7, the first radiation source 9 is used to provide a first radiation to the transparent material layer 8, and the second radiation source 10 is used to provide a second radiation to the transparent material layer 8.

[0093] The supply unit may include a print head 3 (or dispenser) for spraying the composition 6 onto the support platform 7 to form a transparent material layer 8. The number of the print head 3 is at least one, that is, it may be one or more. Specifically, the print head 3 may include a single-channel print head 3 and / or a multi-channel print head 3.

[0094] Specifically, during the 3D inkjet printing process, the print head 3 sprays ink droplets formed by the composition 6 onto the support platform 7 to form a transparent material layer 8 .

[0095] The ultraviolet radiation wavelength of the first radiation provided by the first radiation source 9 is smaller than the ultraviolet radiation wavelength of the second radiation provided by the second radiation source 10. For example, the first radiation source 9 provides the first radiation with a radiation wavelength of 200-280nm, and the second radiation source 10 provides the second radiation with a radiation wavelength of 330-410nm. The first radiation and the second radiation can be light-emitting devices such as ultraviolet light-emitting diodes (UV LEDs) that can provide the above radiation, such as UV LED lamps.

[0096] The number of the first radiation sources 9 can be multiple, for example, two, generally on opposite sides of the print head 3 (eg Figure 3 There are first radiation sources 9 on both the left and right sides of the print head 3. For example, when there are two first radiation sources 9, the two first radiation sources 9 are respectively arranged on opposite sides of the print head 3.

[0097] In a specific implementation, after the composition 6 is sprayed onto the support platform 7 by the print head 3 to form the transparent material layer 8, the first radiation is turned on to provide the first radiation to the transparent material layer 8, to excite the first photoinitiator to release free radicals, and the free radicals trigger the photocurable components therein to emit a polymerization reaction to form a non-flowing partially cured state, wherein the first radiation sources 9 located on opposite sides of the print head 3 are not turned on at the same time, specifically, when the print head 3 moves to the left, the first radiation source 9 located on the right side of the print head 3 is turned on, and when the print head 3 moves to the right, the first radiation source 9 located on the left side of the print head 3 is turned on. After the transparent material layer 8 is irradiated by the first radiation source 9, the second radiation source 10 is turned on to provide the second radiation to the partially cured transparent material layer 8 after being irradiated by the first radiation source 9, to excite the second photoinitiator therein to release free radicals, thereby triggering the photocurable components to further cure to form a layer of a 3D object.

[0098] Specifically, the device comprises a main body 5, which is arranged to form a chamber, and a supporting platform 7, a feeding part, a first radiation source 9, and a second radiation source 10 are arranged in the chamber.

[0099] The second radiation source 10 may be installed on the body 5 , for example, on the top of the chamber.

[0100] The above-mentioned device also includes a carriage 4, which is located in the chamber, for example, movably located in the chamber surrounded by the main body 5. In some specific embodiments, the above-mentioned device also includes a beam located in the chamber, the beam is fixed on the main body 5, and the carriage 4 is movably installed on the beam.

[0101] The first radiation source 9 and the print head 3 are respectively mounted on the carriage 4. During the printing process, the carriage 4 drives the print head 3 to move, and the print head 3 sprays ink droplets formed by the composition 6 onto the support platform to form a transparent material layer on the support platform. After being irradiated by the first radiation source and the second radiation source in turn, the transparent material layer is cured to different degrees at different time periods, and finally forms a layer of a 3D object. Specifically, Figure 3 As shown, during the printing process, the support platform does not move in the horizontal direction, and the carriage 4 can drive the print head 3 to move at a constant speed in the scanning direction relative to the support platform 7.

[0102] The supporting platform is, for example, square, such as a rectangle or a square, but is not limited thereto and may also be designed into other regular or irregular shapes as required.

[0103] The above-mentioned feeding part also includes a container 1 and an ink tube 2. The container 1, the ink tube 2, and the print head 3 are connected in sequence. The container 1 is used to store the above-mentioned composition 6 and transport the composition 6 to the print head 3 through the ink tube 2, so that the composition 6 is sprayed onto the supporting platform 7 through the print head 3 to form a transparent material layer 8.

[0104] In addition, the print head 3 and the support platform 7 can move relative to each other in a first direction, which is parallel to the stacking direction of the layers of the 3D object to be printed, and is also parallel to the direction from the print head 3 to the support platform 7 (or parallel to the direction from the support platform 7 to the print head 3), and can be specifically the height direction / vertical direction of the above-mentioned device (i.e. Figure 3 Thus, after the transparent material layer 8, the print head 3 and the support platform 7 move relative to each other in the first direction to increase the relative distance between the two in the first direction, so that there is enough space between the two to accommodate the new transparent material layer 8, so as to continuously form layers of the 3D object, and these layers are stacked layer by layer to form the 3D object.

[0105] In some specific embodiments, Figure 3 As shown, the above-mentioned device also includes a lifting component 13 connected to the supporting platform 7. The lifting component 13 is used to change the relative distance between the supporting platform 7 and the print head 3 in the first direction. Specifically, it can drive the supporting platform 7 to move down a certain distance relative to the print head 3 in the first direction to increase the relative distance between the two in the first direction, so that there is enough space between the two to accommodate a new transparent material layer 8, so as to continuously form layers of the 3D object, and these layers are stacked layer by layer to form the 3D object.

[0106] Specifically, the lifting component 13 and the print head 3 are located on opposite sides of the support platform 7. Figure 3 As shown, the lifting component 13 is located on the lower side of the supporting platform 7 , and the print head 3 , the first radiation source 9 , the second radiation source 10 , the carriage 4 and other components are located on the upper side of the supporting platform 7 .

[0107] The above device further comprises a leveling component 11 for leveling the transparent material layer 8. The leveling component 11 is arranged between the print head 3 and the first radiation source 9, for example.

[0108] The leveling component 11 may include a leveling rod, and the excess composition 6 distributed on the supporting platform 7 is taken away by the rotation of the leveling rod to improve the accuracy of the transparent material layer 8, thereby improving the molding accuracy of the 3D object.

[0109] In another specific embodiment, the structure of the three-dimensional molding device is as follows: Figure 4 As shown above Figure 3 The difference between the three-dimensional object forming device in the invention is that Figure 4 In the three-dimensional object forming device, the support platform 7 is a rotating platform, which is, for example, circular. During the printing process, the support platform 7 rotates clockwise or counterclockwise (such as Figure 4 The printing head 3 rotates in the direction of the arrow around the supporting platform 7 (in the figure), generally in a uniform rotational motion. The carriage 4 drives the printing head 3 to move at a uniform speed in a radial direction parallel to the supporting platform 7 and spray ink droplets formed by the composition 6. The leveling part levels the composition 6 sprayed onto the supporting platform 7, thereby facilitating the formation of a uniform transparent material layer 8 on the supporting platform 7. After the transparent material layer 8 is formed, the printing head 3 can move upward in the Z direction relative to the supporting platform 7 for a certain distance, so that there is enough space between the printing head 3 and the supporting platform 7 to accommodate a new transparent material layer 8.

[0110] The above three-dimensional object forming device (such as Figure 3 or Figure 4 The device shown in the figure) also includes a controller 12, which can be located outside the chamber, but is not limited to this. The feeding part, the first radiation source 9, the second radiation source 10, the lifting mechanism and other components are respectively connected to the controller 12, and the controller 12 controls each component to perform corresponding operations, for example, controlling the container 1 to supply the composition 6 to the print head 3 through the ink tube 2; controlling the print head 3 to spray the composition 6 to the support platform 7 according to the layer printing data to form a transparent material layer 8; controlling the first radiation source 9 to provide the first radiation to the transparent material layer 8 so that the transparent material layer 8 is partially cured, and then controlling the second radiation source 10 to provide the second radiation to the transparent material layer 8 so that the transparent material layer 8 is further cured to form a layer of the 3D object; controlling the support platform 7 to rotate at a uniform speed along its circumference; after the layer of the 3D object is formed, controlling the support platform 7 and the print head 3 to move relative to each other in the first direction, for example, controlling the lifting component 13 to drive the support platform 7 to move in the height direction to change the relative distance between the support platform 7 and the print head 3, or controlling the print head 3 to move upward in the Z direction relative to the support platform 7 to change the relative distance between the support platform 7 and the print head 3; and controlling the process of repeatedly executing steps S200 to S300, etc.

[0111] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0112] Example 1

[0113] 1. Composition and preparation thereof

[0114] The composition of the composition of this embodiment is shown in Table 1. According to the amount of each component shown in Table 1, it is prepared by the following process:

[0115] (1) placing a (meth)acrylate oligomer, a (meth)acrylate monomer, a stabilizer, a defoamer, and a leveling agent in a glass container, and stirring with a stirrer until the mixture is uniformly mixed to obtain a first mixture;

[0116] (2) adding a photoinitiator to the first mixture and continuing to stir until the photoinitiator is completely dissolved to obtain a second mixture;

[0117] (3) filtering the second mixture through a glass fiber membrane with a pore size of 0.45 μm for the first stage, and then filtering the second mixture through a PP membrane with a pore size of 0.22 μm for the second stage to obtain a filtrate;

[0118] (4) Degassing: The filtrate was decompressed and filtered at a vacuum degree of 0.1 MPa for about 1 hour to remove bubbles in the filtrate to obtain a composition.

[0119] Table 1 Composition

[0120]

[0121] 2. 3D object forming

[0122] Using the above composition, use Figure 3 The three-dimensional molding device shown performs 3D printing to produce a 3D object; wherein the device can be formed by assembling a first radiation source and a second radiation source on a printer model Sailner J500. Its specific structure and printing process are referred to above and will not be repeated here.

[0123] Example 2

[0124] The difference between this embodiment and embodiment 1 is that the composition of the composition is shown in Table 2. During the preparation of the composition, the degassing treatment in step (4) adopts a normal pressure degassing method, that is, standing at room temperature and pressure for 3 hours to remove bubbles in the filtrate to obtain the composition; the other conditions are the same as those in embodiment 1.

[0125] Table 2 Composition

[0126]

[0127] Example 3

[0128] The difference between this embodiment and embodiment 1 is that the composition of the composition is shown in Table 3. During the preparation of the composition, the degassing treatment in step (4) adopts a heating degassing method, that is, the filtrate is degassed at 50° C. for 30 minutes to remove bubbles in the filtrate to obtain the composition; the other conditions are the same as those in embodiment 1.

[0129] Table 3 Composition

[0130]

[0131] a It means that ethoxylated bisphenol A dimethacrylate has 20 ethoxy groups, and there are 10 ethoxy groups on each of the substituents of the two benzene rings.

[0132] Example 4

[0133] The difference between this embodiment and embodiment 1 is that the composition of the composition is shown in Table 4. During the preparation of the composition, during the degassing treatment in step (4), the filtrate is decompressed and filtered for about 3 hours at a vacuum degree of 0.1 MPa to remove bubbles in the filtrate to obtain the composition. The other conditions are the same as those in embodiment 1.

[0134] Table 4 Composition

[0135]

[0136] b It means that ethoxylated bisphenol A dimethacrylate has 30 ethoxy groups, and there are 15 ethoxy groups on each of the substituents of the two benzene rings.

[0137] Example 5

[0138] The difference between this embodiment and embodiment 1 is that the composition of the composition is shown in Table 5; the other conditions are the same as those in embodiment 1.

[0139] Table 5 Composition

[0140]

[0141] cIt means that ethoxylated bisphenol A dimethacrylate has 10 ethoxy groups, and there are 5 ethoxy groups on each of the substituents of the two benzene rings.

[0142] Example 6

[0143] The difference between this embodiment and embodiment 1 is that the composition of the composition is shown in Table 6; the other conditions are the same as those in embodiment 1.

[0144] Table 6 Composition

[0145]

[0146] d It means that ethoxylated bisphenol A dimethacrylate has 40 ethoxy groups, and there are 20 ethoxy groups on each of the substituents of the two benzene rings.

[0147] Example 7

[0148] The difference between this embodiment and embodiment 1 is that the composition of the composition is shown in Table 7; the other conditions are the same as those in embodiment 1.

[0149] Table 7 Composition

[0150]

[0151] Example 8

[0152] The difference between this embodiment and embodiment 1 is that the composition of the composition is shown in Table 8; the other conditions are the same as those in embodiment 1.

[0153] Table 8 Composition

[0154]

[0155] e It means that ethoxylated bisphenol A dimethacrylate has 20 ethoxy groups, and there are 10 ethoxy groups on each of the substituents of the two benzene rings.

[0156] Example 9

[0157] The difference between this embodiment and embodiment 1 is that the composition of the composition is shown in Table 9; the other conditions are the same as those in embodiment 1.

[0158] Table 9 Composition

[0159]

[0160] Comparative Example 1

[0161] The difference between this embodiment and embodiment 6 is that the (meth)acrylate monomer is a low-refractive-index monomer that does not contain a benzene ring structure. The composition of the composition is specifically shown in Table 10; the other conditions are the same as those in embodiment 6.

[0162] Table 10 Composition

[0163]

[0164] Comparative Example 2

[0165] The difference between this comparative example and Example 6 is that only one initiator is used, and the composition of the composition is specifically shown in Table 11; the other conditions are the same as those in Example 6.

[0166] Table 11 Composition

[0167]

[0168] d It means that ethoxylated bisphenol A dimethacrylate has 40 ethoxy groups, and there are 20 ethoxy groups on each of the substituents of the two benzene rings.

[0169] Comparative Example 3

[0170] The difference between this comparative example and Example 6 is that the amount of the first initiator added is too much, and the amount of the second initiator added is too little. The composition of the composition is specifically shown in Table 12; the other conditions are the same as those in Example 6.

[0171] Table 12 Composition

[0172]

[0173] d It means that ethoxylated bisphenol A dimethacrylate has 40 ethoxy groups, and there are 20 ethoxy groups on each of the substituents of the two benzene rings.

[0174] Comparative Example 4

[0175] The difference between this comparative example and Example 6 is that the second initiator adopts a cationic initiator, and the composition of the composition is specifically shown in Table 13; the other conditions are the same as those in Example 6.

[0176] Table 13 Composition

[0177]

[0178] d It means that ethoxylated bisphenol A dimethacrylate has 40 ethoxy groups, and there are 20 ethoxy groups on each of the substituents of the two benzene rings.

[0179] Comparative Example 5

[0180] The difference between this comparative example and Example 6 is that the amount of stabilizer added is too low, and the excess stabilizer content is added to the last monomer. The composition of the composition is specifically shown in Table 14; the other conditions are the same as Example 6.

[0181] Table 14 Composition

[0182]

[0183] d It means that ethoxylated bisphenol A dimethacrylate has 40 ethoxy groups, and there are 20 ethoxy groups on each of the substituents of the two benzene rings.

[0184] Comparative Example 6

[0185] The difference between this comparative example and Example 6 is that the amount of stabilizer added is too high, and the composition of the composition is specifically shown in Table 15; the other conditions are the same as Example 6.

[0186] Table 15 Composition

[0187]

[0188] d It means that ethoxylated bisphenol A dimethacrylate has 40 ethoxy groups, and there are 20 ethoxy groups on each of the substituents of the two benzene rings.

[0189] Comparative Example 7

[0190] The difference between this comparative example and Example 6 is that the proportion of methyl-containing acrylate in the (meth)acrylate monomer is 20%. The composition of the composition is specifically shown in Table 16; the other conditions are the same as those in Example 6.

[0191] Table 16 Composition

[0192]

[0193] d It means that ethoxylated bisphenol A dimethacrylate has 40 ethoxy groups, and there are 20 ethoxy groups on each of the substituents of the two benzene rings.

[0194] Comparative Example 8

[0195] The difference between this comparative example and Example 6 is that the proportion of methyl-containing acrylate in the (meth)acrylate monomer is 100%, and the composition of the composition is specifically shown in Table 17; the other conditions are the same as those in Example 6.

[0196] Table 17 Composition

[0197]

[0198] d It means that ethoxylated bisphenol A dimethacrylate has 40 ethoxy groups, and there are 20 ethoxy groups on each of the substituents of the two benzene rings.

[0199] The performance tests were performed on the compositions and 3D objects in the above embodiments and comparative examples, and the relevant test processes are as follows:

[0200] 1. Viscosity test: Use DV-I digital viscometer to test the viscosity of the composition at room temperature (25°C) and working temperature (about 55°C);

[0201] 2. Surface tension test: Use BZY-1 fully automatic surface tension meter to test the surface tension of the composition at room temperature and working temperature (about 55°C);

[0202] 3. Light transmittance test: The three-dimensional molding device of Example 1 was used to perform 3D printing on the above composition to print a 10 mm*10 mm*10 mm cube (i.e., a 3D object), and the light transmittance of the cube in the horizontal (XY) direction and the layer stacking (Z) direction was tested according to GB / T 2410-2008 standard;

[0203] 4. Refractive index test: The three-dimensional molding device of Example 1 was used to perform 3D printing on the above composition to print a 20 mm*8 mm*4 mm block, and the refractive index of the block was tested according to GB / T 2918-2018 standard using an Abbe refractometer;

[0204] 5. Fluency test: The three-dimensional molding device of Example 1 was used to continuously print the above composition at 55° C. for 4 hours, and the ink discharge of the nozzle was tested before and after printing. If no more than 10 lines were broken before and after printing, the printing fluency test result was recorded as ok (i.e., passed the test), otherwise it was recorded as NG (i.e., the fluency was poor and failed the test);

[0205] 6. Shrinkage test: Using the pycnometer method and taking water as reference, the density ρ1 of the composition before curing and the density ρ2 after complete curing were measured at 25°C. The volume shrinkage was calculated according to the following formula:

[0206]

[0207] Table 18 Performance parameters of the compositions and 3D objects of various embodiments

[0208]

[0209] Table 19 Performance parameters of the compositions and 3D objects of each comparative example

[0210]

[0211] Therefore, the composition of the above embodiment has at least the following advantages:

[0212] (1) The 3D objects of the above embodiments have good light transmittance, high refractive index and other properties. In particular, in embodiments 1-9, the light transmittance of the 3D objects in the XY horizontal direction is higher than 94%, the light transmittance in the Z direction is higher than 92%, and the refractive index is higher than 1.49, showing more excellent transparency, optical consistency, surface clarity uniformity, and high gloss. At the same time, the 3D objects of the embodiments also have the characteristics of low shrinkage and good ink fluidity, and the printed 3D objects will not warp or deform.

[0213] (2) Compared with Comparative Example 1, the acrylate monomer in the composition of Example 6 has a benzene ring structure, and the 3D object prepared has not only good light transmittance, smoothness and other properties, but also has a better refractive index, showing better optical properties;

[0214] (3) The photoinitiator in the composition of Comparative Example 2 contains only the second photoinitiator but not the first photoinitiator. Compared with Comparative Example 2, the composition of Example 6 contains both the first photoinitiator and the second photoinitiator. The properties of the 3D object prepared by the composition, such as the light transmittance in the Z direction, are significantly better than those of the 3D object prepared by Comparative Example 2.

[0215] (4) In the composition of Comparative Example 3, the mass ratio of the first photoinitiator in the photoinitiator is as high as 80%. Compared with Comparative Example 3, the content of the first photoinitiator in the composition of Example 6 is appropriate, and the properties of the prepared 3D object in the XY horizontal direction and the Z direction, such as the transmittance, are significantly better than those of the 3D object prepared in Comparative Example 3;

[0216] (5) In the composition of Comparative Example 4, the second photoinitiator is a cationic photoinitiator instead of a free radical photoinitiator. Compared with Comparative Example 4, the first photoinitiator and the second photoinitiator of Example 6 are both free radical initiators, and the light transmittance and other properties of the prepared 3D object in the XY horizontal direction and the Z direction are better than those of the 3D object prepared in Comparative Example 4;

[0217] (6) Compared with Comparative Examples 5 and 6, the content of the stabilizer and other components in the composition of Example 6 is appropriate, and the properties of the prepared 3D object such as the transmittance in the XY horizontal direction and the Z direction are better than those of the 3D objects in Comparative Examples 5 and 6;

[0218] (7) In Comparative Example 7, the mass of methacrylate monomers accounts for 20% of the total mass of acrylate monomers. In Comparative Example 8, the mass of methacrylate monomers accounts for 100% of the total mass of acrylate monomers (i.e., all acrylate monomers are methacrylate monomers and do not contain acrylate monomers). Compared with Comparative Examples 7 and 8, the content of methacrylate and acrylate in the composition of Example 6 is appropriate, and the properties of the prepared 3D object in terms of light transmittance in the XY horizontal direction and the Z direction are better than those of the 3D objects prepared in Comparative Examples 7 and 8.

[0219] In addition, the use of Figure 4 3D object forming device ( Figure 4 and Figure 3 The differences between the structure of the three-dimensional object forming device and the corresponding printing process are as mentioned above and will not be repeated here). The above embodiments 1-9 and comparative examples 1-8 are implemented respectively, and the results are the same as those of the above-mentioned using Figure 3 The implementation results of the three-dimensional object forming device are similar and will not be repeated here.

[0220] The above describes the embodiments of the present invention. However, the present invention is not limited to the above embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A transparent material composition for three-dimensional molding, characterized in that: The invention comprises the following components in mass ratio: 0-30% (meth)acrylate oligomer, 60-90% (meth)acrylate monomer, 0.8-8% photoinitiator, and 3-10% auxiliary agent; wherein, The photoinitiator comprises a first photoinitiator and a second photoinitiator, the ultraviolet absorption wavelength of the first photoinitiator is lower than the ultraviolet absorption wavelength of the second photoinitiator, and the first photoinitiator and the second photoinitiator are respectively used to initiate the polymerization reaction of the (meth)acrylate monomer, or respectively to initiate the polymerization reaction of the (meth)acrylate monomer and the (meth)acrylate oligomer; The first photoinitiator and the second photoinitiator are free radical initiators respectively; In the photoinitiator, the mass ratio of the first photoinitiator is 10-40%, and the balance is the second photoinitiator; The (meth)acrylate monomer contains a benzene ring structure; The (meth)acrylate monomers include methacrylate monomers and acrylate monomers; in the (meth)acrylate monomers, the mass ratio of the methacrylate monomers is 30-70%, and the balance is the acrylate monomers; The auxiliary agent includes at least one of a stabilizer, a leveling agent, and a defoaming agent; in the transparent material composition for three-dimensional molding, the mass ratio of the stabilizer is 2-5%, and / or the mass ratio of the leveling agent is 0.4-4%, and the mass ratio of the defoaming agent is 0.4-2.5%.

2. The transparent material composition for three-dimensional molding according to claim 1, characterized in that: The ultraviolet absorption wavelength of the first photoinitiator is 200-280 nm, and / or the ultraviolet absorption wavelength of the second photoinitiator is 330-410 nm.

3. The transparent material composition for three-dimensional molding according to any one of claims 1 to 2, characterized in that: The first photoinitiator is selected from one or more of benzoin dimethyl ether, 2-methyl-2-(4-morpholinyl)-1-[4-(methylthio)phenyl]-1-propanone, benzophenone, benzil dimethyl ketal, 2-phenylbenzyl-2-dimethylamine-1-(4-morpholinobenzylphenyl)butanone, 2-hydroxy-methylphenylpropane-1-one, and 1-hydroxy-cyclohexyl-phenyl ketone; and / or, The second photoinitiator is selected from one or more of 2,4,6-trimethylbenzoyl-1-ketone, 2,4,6-trimethylbenzoylphosphine ethyl ester, and phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide.

4. The transparent material composition for three-dimensional molding according to claim 1, characterized in that: The (meth)acrylate monomers include monofunctional (meth)acrylate monomers containing a benzene ring structure and / or multifunctional (meth)acrylate monomers containing a benzene ring structure.

5. The transparent material composition for three-dimensional molding according to claim 4, characterized in that: The monofunctional (meth) acrylate monomer containing a benzene ring structure is selected from at least one of benzyl acrylate, o-phenylphenoxyethyl acrylate, ethoxyphenol acrylate, 2-(p-isopropylphenyl-phenoxy)-ethyl acrylate, nonylphenol propoxy acrylate, phenoxyethyl methacrylate, benzyl methacrylate, ethoxyphenol methacrylate, and 2-(p-isopropylphenyl-phenoxy)-ethyl methacrylate; The multifunctional (meth)acrylate monomer containing a benzene ring structure is selected from at least one of ethoxylated bisphenol A diacrylate containing 1-40 ethoxy groups, ethoxylated bisphenol F acrylate resin containing 1-40 ethoxy groups, and ethoxylated bisphenol A dimethacrylate containing 1-40 ethoxy groups.

6. The transparent material composition for three-dimensional molding according to claim 1, characterized in that: The stabilizer includes a hindered amine stabilizer.

7. The transparent material composition for three-dimensional molding according to claim 1, characterized in that: The transparent material composition for three-dimensional molding has a viscosity of 30-90 cP at room temperature, a viscosity of 6-16 cP at 40-60° C., and a surface tension of 15-35 mN / m at 40-60° C.

8. The method for preparing the transparent material composition for three-dimensional molding according to any one of claims 1 to 7, characterized in that: include: Mixing the (meth)acrylate oligomer, (meth)acrylate monomer, and auxiliary agent to obtain a first mixture; dissolving the photoinitiator in the first mixture to obtain a second mixture; The second mixture is filtered, and the filtrate is collected to obtain the transparent material composition for three-dimensional molding.

9. A three-dimensional object forming method, characterized in that: include: A three-dimensional object is obtained by printing and molding using the transparent material composition for three-dimensional molding described in any one of claims 1 to 7 or the transparent material composition for three-dimensional molding prepared by the preparation method described in claim 8.

10. The three-dimensional object forming method according to claim 9, characterized in that: The printing process includes: S1, forming the transparent material composition for three-dimensional molding into a transparent material layer; S2. sequentially providing the transparent material layer with a first radiation and a second radiation to form a layer of a three-dimensional object; wherein the first radiation is ultraviolet light absorbed by the first photoinitiator, and the second radiation is ultraviolet light absorbed by the second photoinitiator; S3. Repeat steps S1 to S2 to stack the obtained layers of the multiple three-dimensional objects layer by layer to form a three-dimensional object.

11. A three-dimensional object, characterized in that: It is made by printing the transparent material composition for three-dimensional molding according to any one of claims 1 to 7 or the transparent material composition for three-dimensional molding prepared according to the preparation method of claim 8, or it is made by the three-dimensional object molding method according to claim 9 or 10.

12. A three-dimensional object forming device, used for forming the three-dimensional forming transparent material composition according to any one of claims 1 to 7 or the three-dimensional forming transparent material composition prepared according to the preparation method of claim 8, characterized in that: It includes a supporting platform, a feeding part, a first radiation source and a second radiation source, wherein: The feeding part is used to make the transparent material composition for three-dimensional molding form a transparent material layer on the supporting platform; The first radiation source is used to provide first radiation to the transparent material layer; The second radiation source is used to provide second radiation to the transparent material layer.

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