A composition for 3D inkjet printing support structure and its preparation method and application

Abstract

The application provides a composition for 3D inkjet printing support structure and a preparation method and application thereof. The first aspect of the application provides a composition for 3D inkjet printing support structure, which comprises water-soluble monofunctional photocuring monomer, non-reactive polymer, photoinitiator and aqueous solvent; the weight of the water-soluble monofunctional photocuring monomer is 30-50% of the total weight of the composition; the weight of the non-reactive polymer is 30-50% of the total weight of the composition; and the non-reactive polymer has the structure shown in formula 1. The composition provided by the application is helpful to improve the support strength and water solubility of the support structure.

Description

TECHNICAL FIELD

[0001] The present application relates to a composition for 3D inkjet printing support structure and a preparation method and application thereof, and relates to the technical field of 3D inkjet printing. BACKGROUND

[0002] In the process of 3D inkjet printing, for example, when printing an object with a suspended structure, a suspended part below the suspended structure of the object needs to be printed with a support structure so that the target object can be formed; after the target object is formed, the support structure needs to be removed from the target object without affecting the surface precision of the target object; therefore, the support structure needs to have sufficient mechanical strength to support the target object, and at the same time, it is convenient to remove from the target object.

[0003] The types of existing support materials can be divided into: mechanical force removal support materials, water-soluble support materials and alkali-soluble support materials, etc. according to the removal method of the support structure; among them, the water-soluble support material basically does not involve hazardous materials in the process of removing the support structure, so it is widely selected; but the water-soluble support material still has the technical problem of being difficult to balance the support strength and water solubility. Therefore, it is particularly crucial to seek a printing material that can guarantee the support strength and water solubility of the 3D inkjet printing support structure. SUMMARY

[0004] The present application provides a composition for 3D inkjet printing support structure and a preparation method thereof, which is used for printing support structure and improving the support strength and water solubility of the support structure.

[0005] The present application also provides an inkjet printing device and method using the above-mentioned composition for 3D inkjet printing support structure, and a support structure printed by the above-mentioned composition.

[0006] The first aspect of the present application provides a composition for 3D inkjet printing support structure, which comprises water-soluble monofunctional photocurable monomer, non-reactive polymer, photoinitiator and aqueous solvent;

[0007] The weight of the water-soluble monofunctional photocurable monomer is 30% to 50% of the total weight of the composition;

[0008] The weight of the non-reactive polymer is 30% to 50% of the total weight of the composition;

[0009] The non-reactive polymer has the structure shown in Formula 1:

[0010]

[0011] In Formula 1, R1, R2, R3, R4 are independently selected from R5, -(CH2CH2O) z -R5, -(CH2CH2O)n one of H, R5 is a C12-C18 fatty acyl group, z is an integer greater than 0, and n is an integer greater than or equal to 0;

[0012] at least one and up to three of R1, R2, R3, R4 are selected from R5 or -(CH2CH2O) z -R5.

[0013] In one embodiment, the non-reactive polymer has an HLB of 7 to 14.

[0014] In one embodiment, the water-soluble monofunctional photocurable monomer has one or both of the structures shown in Formulas 2 and 3:

[0015]

[0016] In Formula 2, R6 is selected from -H or -CH3, R7, R8 are independently selected from -H, -CH3, -(CH2) m CH3, -CH(CH3)2, -(CH2) m OH, or R7 and R8 form a first cyclic structure selected from -CH2CH2OCH2CH2-, and m is an integer greater than or equal to 1.

[0017]

[0018] In Formula 3, R9, R 10 are independently selected from -H, -CH3, -CHO, -(CH2) m CH3, -CH(CH3)2, -(CH2) m OH, or R9 and R 10 form a second cyclic structure selected from -CH(CH3)COOCH2-, -(CH2) m CO-, and m is an integer greater than or equal to 1.

[0019] In one embodiment, the water-soluble monofunctional photocurable monomer is selected from one or more of N-acryloyl morpholine, 5-methyl-3-vinyl oxazolidine-2-one, N-hydroxyethyl acrylamide, N-vinyl caprolactam, N-vinyl pyrrolidone, N-vinyl oxazolidinone, N,N-diisopropyl acrylamide, N,N-diethyl acrylamide, N-methyl-N-ethyl acrylamide, N-methyl-N-isopropyl acrylamide.

[0020] In one embodiment, the photoinitiator has a weight of 1% to 5% of the total weight of the composition.

[0021] In one specific embodiment, the photoinitiator is a free radical photoinitiator.

[0022] In one specific embodiment, the weight of the aqueous solvent is 10% to 30% of the total weight of the composition.

[0023] In one specific embodiment, the aqueous solvent is selected from one or more of ethylene glycol butyl ether, diethylene glycol butyl ether, ethylene glycol phenyl ether, propylene glycol methyl ether, dipropylene glycol methyl ether, tripropylene glycol methyl ether, propylene glycol propyl ether, dipropylene glycol propyl ether, propylene glycol butyl ether, dipropylene glycol butyl ether, tripropylene glycol butyl ether, propylene glycol phenyl ether, dipropylene glycol dimethyl ether, ethylene glycol ethyl ether, diethylene glycol ethyl ether, ethylene glycol methyl ether, diethylene glycol hexyl ether, ethylene glycol hexyl ether, triethylene glycol methyl ether, triethylene glycol ethyl ether, and diethylene glycol butyl ether.

[0024] In one embodiment, the composition further includes an auxiliary agent selected from one or more of polymerization inhibitors, surfactants, antioxidants, and chain transfer agents.

[0025] In one specific embodiment, the total weight of the additives does not exceed 3% of the total weight of the composition.

[0026] In one specific embodiment, at 25°C, the viscosity of the composition is 15–40 cps and the surface tension is 20–32 mN / m; at 30–70°C, the viscosity of the composition is 9–15 cps and the surface tension is 20–32 mN / m.

[0027] A second aspect of this application provides a method for preparing any of the compositions described above, comprising the following steps:

[0028] Under the condition of avoiding photo-induced polymerization reactions of each component, water-soluble monofunctional photocurable monomer, non-reactive polymer and aqueous solvent are mixed evenly to obtain the first mixture;

[0029] A photoinitiator was added to the first mixture, and after mixing evenly, a second mixture was obtained.

[0030] The second mixture is filtered, and the filtrate is collected to obtain the composition.

[0031] A third aspect of this application provides a 3D inkjet printing apparatus, including an inkjet printhead, wherein the inkjet printhead is capable of printing a support structure using any of the 3D inkjet printing support structure compositions described above.

[0032] The fourth aspect of this application provides a 3D inkjet printing method, the printing process comprising: using the above-described 3D inkjet printing apparatus, and using any of the above-described compositions for printing 3D inkjet printing support structures to print a support structure.

[0033] In a specific embodiment, the method further comprises printing a target 3D object under the support of the support structure.

[0034] The fifth aspect of the present application provides a support structure, which is printed by the 3D inkjet printing support structure composition according to any one of the above.

[0035] The present application provides a 3D inkjet printing support material composition. On one hand, the non-reactive polymer contained in the composition can promote phase separation in the photocured product formed after the photocuring reaction of the composition, ensuring the support strength of the support structure. On the other hand, the non-reactive polymer helps to drive the photocured product to diffuse into the water phase, and it has a certain emulsifying effect, which can effectively promote the photocured product to dissolve in the form of emulsion droplets, improving the dissolution rate of the support structure in water. Therefore, the composition provided by the present application helps to improve the support strength and water solubility of the support structure. DETAILED DESCRIPTION

[0036] To make the objectives, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without any creative work fall within the scope of protection of the present application.

[0037] The first aspect of the present application provides a 3D inkjet printing support structure composition, which comprises a water-soluble monofunctional photocuring monomer, a non-reactive polymer, a photoinitiator and an aqueous solvent.

[0038] The weight of the water-soluble monofunctional photocuring monomer is 30% to 50% of the total weight of the composition;

[0039] The weight of the non-reactive polymer is 30% to 50% of the total weight of the composition;

[0040] The non-reactive polymer has the structure shown in Formula 1:

[0041]

[0042] In Formula 1, R1, R2, R3 and R4 are independently selected from R5, -(CH2CH2O) z -(CH2CH2O) n R5 is a C12-C18 aliphatic acyl group, z is an integer greater than 0, and n is an integer greater than or equal to 0;

[0043] at least one and at most three of R1, R2, R3, R4are selected from R5or -(CH2CH2O) z -R5.

[0044] The composition provided by the application is suitable for 3D inkjet printing support structure. The water-soluble monofunctional photocuring monomer is photocured under the action of a photoinitiator to obtain a photocured product. The hydrophilic property of the non-reactive polymer enables it to have good compatibility with the water-soluble monofunctional photocuring monomer and the aqueous solvent, so that the composition forms a transparent and uniform system and drives the photocured product to diffuse to the water phase to realize water solubility. The lipophilic property enables it to produce phase separation in the photocured product, thereby ensuring the support strength of the support structure. In addition, the non-reactive polymer has a certain emulsifying effect, which can effectively promote the photocured product to be dissolved in the form of emulsion droplets, thereby significantly improving the dissolution rate of the support structure in water. Therefore, the composition provided by the application helps to improve the support strength and water solubility of the support structure.

[0045] In a specific embodiment, the non-reactive polymer refers to a polymer that does not participate in photocuring reaction. The weight of the non-reactive polymer is 30% to 50% of the total weight of the composition. When the content of the non-reactive polymer is less than 30%, the phase separation effect produced by the non-reactive polymer in the photocured product is small, and the support strength is difficult to meet the printing requirements. When the content of the non-reactive polymer is greater than 50%, the phase separation effect produced is too strong, resulting in a hard support structure obtained by printing, and the disintegration speed in water is slow and the solubility is poor.

[0046] Further, the non-reactive polymer provided by the application has a structure shown in Formula 1:

[0047]

[0048] In Formula 1, R1, R2, R3, R4are independently selected from R5, -(CH2CH2O) z -R5, -(CH2CH2O) n one of R1, R2, R3, R4is -(CH2CH2O)nH, R5is a fatty acyl group with 12 to 18 carbon atoms, z is an integer greater than 0, and n is an integer greater than or equal to 0;

[0049] at least one and at most three of R1, R2, R3, R4are selected from R5or -(CH2CH2O) z -R5.

[0050] In the present application, the fatty acyl group refers to a fatty hydrocarbon with 12 to 18 carbon atoms containing an acyl group, for example, -OCC 17 H 33 , -OCC 11 H 23 , -OCC 15 H31 etc.

[0051] In the present application, -(CH2CH2O) z -R5represents a C12-C18 fatty acyl group connected to the oxygen atom in formula 1 through z CH2CH2O groups, z being an integer greater than 0, such as 1, 2, 3, 4, 5, etc. In addition, when at least two of R1, R2, R3, R4are selected from -(CH2CH2O) z -R5, R5and z can be the same or different.

[0052] In the present application, -(CH2CH2O) n H represents an H atom connected to the oxygen atom in formula 1 through n CH2CH2O groups, n being an integer greater than or equal to 0, and when n is equal to 0, it means that the H atom is directly connected to the oxygen atom.

[0053] Further, the HLB of the non-reactive polymer is 7-14. HLB refers to the hydrophilic-lipophilic balance value, which can be 7, 8, 9, 10, 11, 12, 13, 14 or within a range between any two of them. When the HLB is 7-14, the support structure printed by the composition has good support strength and water dissolution rate, otherwise, when the HLB is greater than 14, it will lead to a decrease in support strength and an increase in water absorption, and the size accuracy of the printed support structure will fluctuate greatly due to humidity changes; when the HLB is less than 7, although the degree of phase separation can be improved, the support strength of the support structure can be ensured, but the water dissolution rate is low.

[0054] It can be understood that the non-reactive polymer can include one or more than two specific non-reactive polymers, each of which has a corresponding HLB, which can be obtained by querying or calculation according to conventional technical means in the art. In addition, it should be noted that when the non-reactive polymer includes two or more than two specific non-reactive polymers, the HLB has additive property, and the calculation formula is as follows: HLB = ∑(the HLB of each non-reactive polymer * the content of each non-reactive polymer) / the total content of each non-reactive polymer. For example, when the non-reactive polymer only includes one specific non-reactive polymer A, the HLB of the non-reactive polymer A is equal to the HLB of the non-reactive polymer; when the non-reactive polymer includes two specific non-reactive polymers A and B, and the weight of A is X1% of the total weight of the composition, and the weight of B is X2% of the total weight of the composition, then the HLB of the non-reactive polymer = (the HLB of the non-reactive polymer A * X1% + the HLB of the non-reactive polymer B * X2%) / (X1% + X2%).

[0055] When two or more specific polymer species are included in the non-reactive polymer, the present application does not limit the specific ratio of the two, as long as the sum of their weights and the HLB calculation result meet the range defined in the present application.

[0056] Further, the non-reactive polymer is selected from one or more of polyoxyethylene sorbitan fatty acid esters, sorbitan fatty acid esters. According to the difference in the number of carbon atoms in the fatty acid in the molecular structure, the polyoxyethylene sorbitan fatty acid esters can be specifically selected from one or more of Tween 20, Tween 21, Tween 40, Tween 60, Tween 61, Tween 65, Tween 80, Tween 81, Tween 85; the sorbitan fatty acid esters can be specifically selected from one or more of Span 20, Span 40, Span 60, Span 65, Span 80, Span 85.

[0057] In a specific embodiment, the water-soluble monofunctional photocurable monomer refers to a monomer compound capable of undergoing a curing reaction under light induction, and only one group participating in the photocuring reaction is included in its molecular structure, and it can be dissolved in polar solvents. The weight of the water-soluble monofunctional photocurable monomer is 30% to 50% of the total weight of the composition. When the content of the water-soluble monofunctional photocurable monomer is less than 30%, it will affect the support strength of the support structure, and when the content of the water-soluble monofunctional photocurable monomer is more than 50%, it will affect the dissolution rate of the support structure in water.

[0058] Further, the water-soluble monofunctional photocurable monomer can be selected from one or both of N-vinyl monomers and N-acrylamide monomers, wherein the N-acrylamide monomer has the structure shown in Formula 2, and the N-vinyl monomer has the structure shown in Formula 3:

[0059]

[0060] In Formula 2, R6 is selected from -H or -CH3, R7 and R8 are independently selected from -H, -CH3, -(CH2) m CH3, -CH(CH3)2, -(CH2) m OH, or R7 and R8 form a first cyclic structure between them, the first cyclic structure is -CH2CH2OCH2CH2-, and m is an integer greater than or equal to 1;

[0061]

[0062] In formula 3, R9, R 10 are independently selected from -H, -CH3, -CHO, -(CH2) m CH3, -CH(CH3)2, -(CH2) m OH, or R9and R 10 form a second cyclic structure selected from one of -CH(CH3)COOCH2-, -(CH2) m CO-, m is an integer greater than or equal to 1.

[0063] Further, the water-soluble monofunctional photocurable monomer is selected from one or more of N-acryloylmorpholine, 5-methyl-3-vinyl oxazolidine-2-one, N-hydroxyethyl acrylamide, N-vinyl caprolactam, N-vinyl pyrrolidone, N-vinyl oxazolidone, N,N-diisopropyl acrylamide, N,N-diethyl acrylamide, N-methyl-N-ethyl acrylamide, N-methyl-N-isopropyl acrylamide.

[0064] In one specific embodiment, the photoinitiator refers to a compound capable of promoting free radical reaction under irradiation of light at a wavelength in the ultraviolet, near-ultraviolet or visible light region, and the specific type is not further limited in the present application. The weight of the photoinitiator is 1% to 5% of the total weight of the composition.

[0065] Further, the photoinitiator is a free radical photoinitiator.

[0066] Further, the free radical photoinitiator is selected from one or more of benzoin ethyl ether, benzoin α,α-dimethyl benzil ketal (BDK), α,α-diethoxy acetophenone, 2-hydroxy-2-methyl-phenylpropanone-1 (1173), 1-hydroxy-cyclohexyl phenyl ketone (184), 2-isopropyl thioxanthone (ITX), 2-hydroxy-2-methyl-p-hydroxyethoxy phenylpropanone-1, 2-methyl-1-[4-methylthio phenyl]-2-morpholinyl-1-propanone (907), [2-benzyl-2-dimethylamino-1-(4-morpholinyl phenyl) butanone-1] (369), benzoyl formate (MBF), 2,4,6-trimethyl benzoyl-diphenyl phosphine oxide (TPO), phenyl bis(2,4,6-trimethyl benzoyl) phosphine oxide (XBPO), phenyl (2,4,6-trimethyl benzoyl) lithium phosphate (LAP), 4-p-toluenesulfenyl benzophenone.

[0067] In one specific embodiment, the aqueous solvent refers to a component capable of improving the solubility of the support structure in water, and is also a component for adjusting the composition to low viscosity. The weight of the aqueous solvent is 10% to 30% of the total weight of the composition.

[0068] Further, the aqueous solvent is selected from one or more of ethylene glycol butyl ether, diethylene glycol butyl ether, ethylene glycol phenyl ether, propylene glycol methyl ether, dipropylene glycol methyl ether, tripropylene glycol methyl ether, propylene glycol propyl ether, dipropylene glycol propyl ether, propylene glycol butyl ether, dipropylene glycol butyl ether, tripropylene glycol butyl ether, propylene glycol phenyl ether, dipropylene glycol dimethyl ether, ethylene glycol ethyl ether, diethylene glycol ethyl ether, ethylene glycol methyl ether, diethylene glycol methyl ether, diethylene glycol hexyl ether, ethylene glycol hexyl ether, triethylene glycol methyl ether, triethylene glycol ethyl ether, diethylene glycol butyl ether.

[0069] In one embodiment, the composition further comprises an auxiliary agent, preferably selected from one or more of a polymerization inhibitor, a surfactant, an antioxidant, a chain transfer agent.

[0070] Further, the total weight of the auxiliary agent is not higher than 3% of the total weight of the composition.

[0071] Further, the polymerization inhibitor refers to a compound that prevents the polymerization of free radicals in the composition, thereby improving the storage stability of the composition. Preferably, the product can improve the storage stability and has no effect on the photocuring reaction of the composition. Further, the polymerization inhibitor is selected from one or more of 4-hydroxy-2,2,6,6-tetramethylpiperidine nitroxide radical (inhibitor 701), 4-oxo-2,2,6,6-tetramethyl-4-piperidine (inhibitor 702), tetramethylpiperidine nitroxide phosphite triester (inhibitor 705), N-nitroso-N-phenylhydroxylamine aluminum (inhibitor 510).

[0072] The surfactant refers to a substance that can reduce the surface tension of the composition and is beneficial to improve the flowability of the composition. Further, the surfactant is selected from polysiloxane surfactants, such as BYK-333, BYK-337, BYK-371, BYK-377, BYK1798, BYK-UV3530, BYK-UV3575, etc. of BYK company, Tego wet 270, TEGO wet 500, Tego Glide 450, TEGO RAD 2010, TEGO RAD 2011, etc. of Degos company.

[0073] The antioxidant refers to a substance capable of delaying or inhibiting the oxidation of the polymer, which can be, for example, 2,6-di-tert-butyl-4-methylphenol, beta-tetra[3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid] pentaerythritol ester, beta-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid n-octadecyl ester, 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 4-[(4,6-dioctylthio-1,3,5-triazin-2-yl) amino]-2,6-di-tert-butylphenol, dilauryl thiodipropionate, tris(nonylphenyl) phosphite, triphenyl phosphite, 2-mercaptobenzimidazole, etc.

[0074] The chain transfer agent refers to a substance capable of effectively initiating the polymerization of monomers by the transferred chain radicals to form new molecular chains, which can effectively control the size of the molecular weight while keeping the polymerization rate unchanged. Further, the chain transfer agent can be n-octyl mercaptan (NOM), n-dodecyl mercaptan (NDM), tert-nonyl mercaptan (TNM), tert-dodecyl mercaptan (TDM), 1,8-dimercapto-3,6-dioxaoctane (DMDO), 2-ethylhexyl mercaptoacetate (2-EHTG), and 2,4-diphenyl-4-methyl-1-pentene (AMSD), etc.

[0075] It can be understood that the use of different compounds for each component or the use of different proportions of each component will affect the properties of the 3D inkjet printing support structure. In the present application, by adjusting the specific selection of each component and adjusting the proportion between each component, a composition with low viscosity for 3D inkjet printing support structure can be obtained. Compared with SLA technology and DLP technology, 3D inkjet printing technology has higher requirements for the viscosity and fluidity of the 3D inkjet printing material, such as reducing the viscosity of the 3D inkjet printing material to a suitable viscosity for normal ejection within the normal working temperature range of the print head, such as 9-15 cp, especially when the normal working temperature of the print head is lower than 80℃, the viscosity of the 3D inkjet printing material is required to be instantaneously reduced to a suitable viscosity for normal ejection, which requires the 3D inkjet printing material to have a lower viscosity at room temperature 25℃, such as less than 50 cp. In a specific embodiment, at 25℃, the viscosity of the composition is 15-40 cps, and the surface tension is 20-32 mN / m; at 30-70℃, the viscosity of the composition is 9-15 cps, and the surface tension is 20-32 mN / m, so that the composition has a suitable viscosity and surface tension for the ejection of the print head, which not only facilitates the smooth progress of 3D printing, but also saves energy consumption and effectively prolongs the service life of the print head.

[0076] The second aspect of the present application provides a preparation method of the composition described above, comprising the following steps:

[0077] The water-soluble monofunctional photocuring monomer, the non-reactive polymer and the aqueous solvent are mixed uniformly under the condition that the components are not induced to occur polymerization reaction by light, to obtain a first mixture;

[0078] A photoinitiator is added to the first mixture, and after being mixed uniformly, a second mixture is obtained;

[0079] The second mixture is filtered, and the filtrate is collected to obtain the composition.

[0080] In one specific embodiment, the order of adding the components is not limited during the mixing process of the water-soluble monofunctional photocuring monomer, the non-reactive polymer and the aqueous solvent.

[0081] In one specific embodiment, the filtering can be performed by multiple filtering, and in particular, can be performed by step-by-step filtering. Specifically, the second mixture can be filtered at least twice by using microporous filter membranes; wherein the pore size of the microporous filter membrane used in the first filtering is larger than the pore size of the microporous filter membrane used in the second filtering, and the pore size of the microporous filter membrane used in the last filtering is smaller than the pore size of the nozzle hole of the printing head in the 3D inkjet printing device, so as to ensure that the 3D inkjet printing support structure has good printing fluency and avoids clogging the printing head nozzle.

[0082] Further, the second mixture is filtered by using a two-stage filtering method, wherein the first filtering is performed by using a glass fiber membrane with a pore size of 0.45-0.6 μm, and the second filtering is performed by using a polypropylene membrane with a pore size of 0.2 μm.

[0083] In one specific embodiment, after the second mixture is filtered, the collected filtrate can also be subjected to degassing treatment. By degassing the filtrate, it is further ensured that the composition has very good fluency during use, and avoids the interference of air bubbles in the composition to cause printing disconnection and further affect the forming precision of the support structure.

[0084] Further, the degassing operation can be one of reduced-pressure degassing, normal-pressure degassing and heating degassing, or any two or more of them can be selected. Generally, the degassing treatment time is controlled to be not more than 5 hours, and further, the degassing time is controlled to be 0.5-3 hours.

[0085] The third aspect of the present application provides a 3D inkjet printing device, which comprises an inkjet printing head, and the inkjet printing head can print a support structure by using any of the above-mentioned 3D inkjet printing support structure compositions.

[0086] The fourth aspect of the present application provides a 3D inkjet printing method, and the printing process comprises using the 3D inkjet printing device and printing the support structure by using the 3D inkjet printing support structure composition.

[0087] In a specific embodiment, the method further comprises printing a target 3D object under the support of the support structure.

[0088] The fifth aspect of the present application provides a support structure, which is printed by using the 3D inkjet printing support structure composition.

[0089] In the present application, the support structure comprises any structure other than the target object in the printing process of the target object, and of course the composition provided by the present application can also be used to print the target object meeting the requirements.

[0090] The present application provides a 3D inkjet printing support material composition, on the one hand, the non-reactive polymer contained therein can promote the phase separation of the photocured product formed after the photocuring reaction of the composition, and ensure the support strength of the support structure; on the other hand, the non-reactive polymer helps to drive the photocured product to diffuse to the water phase, and has a certain emulsifying effect, which can effectively promote the photocured product to be dissolved in the form of emulsion droplets, and improve the dissolution rate of the support structure in water. Therefore, the composition provided by the present application helps to improve the support strength and water solubility of the support structure.

[0091] The following will be described in detail in combination with specific embodiments:

[0092] Example 1

[0093] The composition of the 3D inkjet printing support structure composition provided in the present embodiment is shown in Table 1.

[0094] Table 1 Composition of the composition provided in Example 1

[0095]

[0096] The HLB of the non-reactive polymer in the present embodiment is 10.

[0097] The preparation method of the composition provided in the present embodiment is as follows:

[0098] Step 1, place all the ingredients except the photoinitiator in a glass container, and use a stirrer to stir to obtain a first mixture; then add the photoinitiator to the first mixture, and continue to stir until the photoinitiator is completely dissolved to obtain a second mixture;

[0099] Step 2, the second mixture is subjected to primary filtration with a 0.6 μm glass fiber membrane and secondary filtration with a 0.2 μm polypropylene membrane (PP membrane) to obtain a filtrate;

[0100] Step 3, the filtrate is subjected to vacuum filtration under a vacuum degree of 0.1 MPa for 1 hour to remove bubbles in the filtrate, and finally the above composition is obtained.

[0101] Example 2

[0102] The composition of the composition for 3D inkjet printing support structure provided in this example is shown in Table 2.

[0103] Table 2 Composition of the composition provided in Example 2

[0104]

[0105]

[0106] In this example, the HLB of Span20 is 8.6, and the HLB of Tween20 is 16.7, so the HLB of the non-reactive polymer = (8.6*30%+16.7*17.8%) / 47.8% = 11.61.

[0107] The preparation method provided in this example can refer to Example 1, except that the component composition is different, and in Step 3, the filtrate obtained in Step 2 is heated to 40℃ for degassing treatment, and the degassing time is 50 min.

[0108] Example 3

[0109] The composition of the composition for 3D inkjet printing support structure provided in this example is shown in Table 3.

[0110] Table 3 Composition of the composition provided in Example 3

[0111]

[0112] In this example, the HLB of Span80 is 4.3, and the HLB of Tween21 is 13.3, so the HLB of the non-reactive polymer = (4.3*19.1%+13.3*28.7%) / 47.8% = 9.70.

[0113] The preparation method provided in this example can refer to Example 1, except that the component composition is different, and in Step 3, the vacuum filtration time is 2 hours.

[0114] Example 4

[0115] The composition of the composition for 3D inkjet printing support structure provided in this example is shown in Table 4.

[0116] Table 4. Composition of the composition provided in Example 4

[0117]

[0118] In this embodiment, the HLB of Span 80 is 4.3 and the HLB of Tween 20 is 16.7. Therefore, the HLB of the non-reactive polymer is (4.3 * 14.3% + 16.7 * 21.5%) / 35.8% = 11.74.

[0119] The preparation method provided in this embodiment can be referred to in Embodiment 1. The difference is that the composition is different, and in step 3, degassing is carried out by static degassing under normal pressure for 3 hours.

[0120] Example 5

[0121] The composition of the 3D inkjet printing support structure provided in this embodiment is shown in Table 5.

[0122] Table 5. Composition of the composition provided in Example 5

[0123]

[0124]

[0125] In this embodiment, the HLB of Span20 is 8.6 and the HLB of Tween20 is 16.7. Therefore, the HLB of the non-reactive polymer is (8.6*16.5%+16.7*16.5%) / 33%=12.65.

[0126] The preparation method provided in this embodiment can be referred to in Embodiment 1. The difference is that the composition is different, and in step 3, the filtrate obtained in step 2 is heated to 50°C for degassing treatment for 30 minutes.

[0127] Example 6

[0128] The composition of the 3D inkjet printing support structure provided in this embodiment is shown in Table 6.

[0129] Table 6 Composition of the composition provided in Example 6

[0130]

[0131] In this embodiment, the HLB of Span80 is 4.3 and the HLB of Tween21 is 13.3. Therefore, the HLB of the non-reactive polymer is (4.3 * 20% + 13.3 * 24%) / 44% = 9.21.

[0132] The preparation method provided in the embodiment can refer to Embodiment 1, and the only difference is that the ingredient composition is different.

[0133] Embodiment 7

[0134] The composition of the composition for 3D inkjet printing support structure provided in the embodiment is shown in Table 7.

[0135] Table 7 Composition of the composition provided in Embodiment 7

[0136]

[0137] The HLB of the non-reactive polymer in the embodiment is 6.7.

[0138] The preparation method provided in the embodiment can refer to Embodiment 1, and the only difference is that the ingredient composition is different.

[0139] Embodiment 8

[0140] The composition of the composition for 3D inkjet printing support structure provided in the embodiment is shown in Table 8.

[0141] Table 8 Composition of the composition provided in Embodiment 8

[0142]

[0143] The HLB of the non-reactive polymer in the embodiment is 14.9.

[0144] The preparation method provided in the embodiment can refer to Embodiment 1, and the only difference is that the ingredient composition is different.

[0145] Comparative Example 1

[0146] The composition of the composition for 3D inkjet printing support structure provided in the comparative example is shown in Table 9.

[0147] Table 9 Composition of the composition provided in Comparative Example 1

[0148]

[0149] The preparation method provided in the comparative example can refer to Embodiment 1, and the only difference is that the ingredient composition is different.

[0150] Comparative Example 2

[0151] The composition of the composition for 3D inkjet printing support structure provided in the comparative example is shown in Table 10.

[0152] Table 10 Composition of the composition provided in Comparative Example 2

[0153]

[0154] The HLB of the non-reactive polymer in this comparative example is 9.6.

[0155] The preparation method provided in this comparative example can refer to Example 2, and the only difference is that the ingredient composition is different.

[0156] Comparative Example 3

[0157] The composition of the 3D inkjet printing support structure composition provided in this comparative example is shown in Table 11.

[0158] Table 11 Composition of the composition provided in Comparative Example 3

[0159]

[0160] The HLB of the non-reactive polymer in this comparative example is 7.25.

[0161] The preparation method provided in this comparative example can refer to Example 3, and the only difference is that the ingredient composition is different.

[0162] Comparative Example 4

[0163] The composition of the 3D inkjet printing support structure composition provided in this comparative example is shown in Table 12.

[0164] Table 12 Composition of the composition provided in Comparative Example 4

[0165]

[0166] The HLB of the non-reactive polymer in this comparative example is 11.5.

[0167] The preparation method provided in this comparative example can refer to Example 4, and the only difference is that the ingredient composition is different.

[0168] Comparative Example 5

[0169] The composition of the 3D inkjet printing support structure composition provided in this comparative example is shown in Table 13.

[0170] Table 13 Composition of the composition provided in Comparative Example 5

[0171]

[0172] The HLB of Span20 in this comparative example is 8.6, the HLB of Tween20 is 16.7, and the HLB of the non-reactive polymer is = (8.6*13% + 16.7*13%) / 26% = 12.65.

[0173] The preparation method provided in this comparative example can refer to Example 5, and the only difference is that the ingredient composition is different.

[0174] Comparative Example 6

[0175] The composition of the 3D inkjet printing support structure composition provided in the present comparative example is shown in Table 14.

[0176] The composition of the composition provided in Comparative Example 6 is shown in Table 14.

[0177]

[0178]

[0179] The HLB of Span 80 in the present comparative example is 4.3, and the HLB of Tween 21 is 13.3, so the HLB of the non-reactive polymer = (4.3*25% + 13.3*30%) / 55% = 9.21.

[0180] The preparation method provided in the present comparative example can refer to Example 6, and the only difference is that the ingredient composition is different.

[0181] Comparative Example 7

[0182] The composition of the 3D inkjet printing support structure composition provided in the present comparative example is shown in Table 15.

[0183] The composition of the composition provided in Comparative Example 7 is shown in Table 15.

[0184]

[0185] The HLB of the non-reactive polymer in the present comparative example is 7.1.

[0186] The preparation method provided in the present comparative example can refer to Example 7, and the only difference is that the ingredient composition is different.

[0187] Comparative Example 8

[0188] The composition of the 3D inkjet printing support structure composition provided in the present comparative example is shown in Table 16.

[0189] The composition of the composition provided in Comparative Example 8 is shown in Table 16.

[0190]

[0191]

[0192] The HLB of the non-reactive polymer in the present comparative example is 18.8.

[0193] The preparation method provided in the present comparative example can refer to Example 8, and the only difference is that the ingredient composition is different.

[0194] Example 9

[0195] The present embodiment provides a 3D inkjet printing device, comprising an inkjet printhead capable of printing a support structure using the 3D inkjet printing support structure composition of any of the preceding embodiments. Further, a target object can also be printed on the support structure.

[0196] Example 10

[0197] The present embodiment provides a 3D inkjet printing method, which can use the 3D inkjet printing device of Example 9 to print a support structure using the 3D inkjet printing support structure composition of any of the preceding embodiments.

[0198] The 3D inkjet printing support structure compositions provided in the above embodiments and comparative examples were tested for performance, and the test methods are as follows, and the test results are shown in Tables 17-18.

[0199] 1. Viscosity

[0200] The viscosity of the composition was tested using a DV-I digital viscometer.

[0201] 2. Surface tension

[0202] The surface tension of the composition was tested using a BZY-1 automatic surface tension meter.

[0203] 3. Smoothness test

[0204] The composition in the present application was applied to a Sinar J5013D light-cured inkjet printer for continuous printing for 4 hours, and the ink ejection of the printhead before and after printing was tested. If the number of broken lines before and after printing was not more than 10, it was indicated as OK, otherwise it was indicated as NG.

[0205] 4. Support strength

[0206] The composition was applied to a Sinar J501 3D light-cured inkjet printer to print a 40mm*40mm*10mm square block, and the surface hardness of the support structure was measured by a Shore hardness tester A according to GB / T 2411-2008 "Standard for Determination of Indentation Hardness (Shore Hardness) of Plastics and Rigid Rubbers Using a Durometer".

[0207] 5. Dissolution rate

[0208] The composition was applied to a Sinar J501 3D light-cured inkjet printer, and the temperature of the printhead was set to 30-70°C. A 10mm*10mm*10mm cube was printed, and after printing, the cube (which can be a sample of the cured product of the composition or a sample of the support structure) was immersed in 500mL of aqueous solution, and the time for complete dissolution of the cube, e.g. the support structure sample, was recorded.

[0209] 6. Separation performance

[0210] The composition was applied to a Seine J501 3D photopolymer inkjet printer, and the printhead temperature was set to 30-70°C. A cube with a length, width, and height of 10mm × 10mm × 10mm was printed. After printing, the cube (which can be a product sample after curing the composition or a support structure sample) was separated from the printing platform. The degree of difficulty in separating the cube, such as the support structure sample, from the printing platform was evaluated. "OK" indicates that it is relatively easy to separate, and "NG" indicates that it is not easy to separate.

[0211] Table 17 Performance test results of the compositions and supporting structures provided in Examples 1-8

[0212]

[0213]

[0214] Table 18 Performance test results of the compositions and support structures provided in Comparative Examples 1-8

[0215]

[0216] According to Tables 17-18, the compositions provided in Examples 1-8 have a viscosity of 15-40 cps and a surface tension of 20-32 mN / m at room temperature (25°C), and a viscosity of 9-15 cps and a surface tension of 20-32 mN / m at operating temperature (30-70°C). Therefore, the compositions provided in Examples 1-8 can not only perform normal inkjet printing at high temperatures such as 70°C, but also at lower operating temperatures such as 30°C, thereby extending the lifespan of the printhead.

[0217] Although the support structure specimens printed according to standard GB / T 2411-2008 using the compositions provided in Examples 1-8 have lower support strength than Comparative Example 1, they still meet the usage requirements. The support hardness is between 40A and 80A, the support strength is moderate, the support structure adheres strongly to the solid model, and the solid model is not prone to deformation defects such as warping or concavity. The water solubility rate is better than that of Comparative Examples 1, 4, and 5. The support structure can dissolve quickly in aqueous solution, improving the post-processing efficiency of the target object. For example, the dissolution time of a 10mm×10mm×10mm support structure specimen in aqueous solution is less than 80 minutes. At the same time, the support structure is relatively easy to separate from the printing platform.

[0218] Comparative Example 1 does not add non-reactive polymer, although the support strength is good, but the water soluble rate is slow, and the separation performance is poor; Comparative Examples 2, 3, 7 and 8 use other non-reactive polymers, Comparative Example 6 uses a non-reactive polymer with a weight greater than 50 parts by weight, and the printing fluidity is poor, which cannot be normally inkjet printed; Comparative Example 4 uses polyethylene glycol 600 as a non-reactive polymer, which cannot guarantee the support strength of the support structure; Comparative Example 5 uses a non-reactive polymer with a weight less than 30 parts by weight, which cannot guarantee the support strength of the support structure.

[0219] The HLB of the non-reactive polymer in Example 7 is less than 7, and the water soluble rate is low, and the HLB of the non-reactive polymer in Example 8 is greater than 14, although the support strength of the support structure can meet the use requirements, but it is lower than that of Examples 1-7; therefore, compared with Examples 7-8, the non-reactive polymer provided in Examples 1-6 has a suitable HLB value, which helps to further improve the support strength and water solubility of the support structure.

[0220] In summary, the composition provided in the present application helps to improve the support strength and water solubility of the support structure.

[0221] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A composition for a 3D inkjet printing support structure, characterized in that, Including water-soluble monofunctional photocurable monomers, non-reactive polymers, photoinitiators, and aqueous solvents; The weight of the water-soluble monofunctional photocurable monomer is 30% to 50% of the total weight of the composition; The weight of the non-reactive polymer is 30% to 50% of the total weight of the composition; The non-reactive polymer has the structure shown in Formula 1: Formula 1 In Equation 1, R1, R2, R3, and R4 are independently selected from R5 and -(CH2CH2O). z -R5、-(CH2CH2O) n One of H, R5 is a fatty acyl group of C12~C18, z is an integer greater than 0, and n is an integer greater than or equal to 0; At least one and at most three of R1, R2, R3, and R4 are selected from R5 or -(CH2CH2O). z -R5; The HLB value of the non-reactive polymer is 7-14; The water-soluble monofunctional photocurable monomer has one or two of the structures shown in Formulas 2-3: Formula 2 In Equation 2, R6 is selected from -H or -CH3, and R7 and R8 are independently selected from -H, -CH3, and -(CH2). m CH3, -CH(CH3)2, -(CH2) m OH, or R7 and R8 form a first ring structure, the first ring structure being -CH2CH2OCH2CH2-, where m is an integer greater than or equal to 1; Formula 3 In Equation 3, R9, R 10 Independently selected from -H, -CH3, -CHO, and -(CH2). m CH3, -CH(CH3)2, -(CH2) m OH, or R9 and R 10 A second ring structure is formed between them, and the second ring structure is selected from -CH(CH3)COOCH2- and -(CH2). m One of CO-, where m is an integer greater than or equal to 1.

2. The composition according to claim 1, characterized in that, The water-soluble monofunctional photocurable monomer is selected from one or more of N-acrylomorpholine, 5-methyl-3-vinyloxazolidin-2-one, N-hydroxyethylacrylamide, N-vinylcaprolactam, N-vinylpyrrolidone, N-vinyloxazolidinone, N,N-diisopropylacrylamide, N,N-diethylacrylamide, N-methyl-N-ethylacrylamide, and N-methyl-N-isopropylacrylamide.

3. The composition according to claim 1, characterized in that, The photoinitiator accounts for 1% to 5% of the total weight of the composition.

4. The composition according to claim 1 or 3, characterized in that, The photoinitiator is a free radical photoinitiator.

5. The composition according to claim 1, characterized in that, The weight of the aqueous solvent is 10% to 30% of the total weight of the composition.

6. The composition according to claim 1 or 5, characterized in that, The aqueous solvent is selected from one or more of ethylene glycol butyl ether, diethylene glycol butyl ether, ethylene glycol phenyl ether, propylene glycol methyl ether, dipropylene glycol methyl ether, tripropylene glycol methyl ether, propylene glycol propyl ether, dipropylene glycol propyl ether, propylene glycol butyl ether, dipropylene glycol butyl ether, tripropylene glycol butyl ether, propylene glycol phenyl ether, dipropylene glycol dimethyl ether, ethylene glycol ethyl ether, diethylene glycol ethyl ether, ethylene glycol methyl ether, diethylene glycol methyl ether, diethylene glycol hexyl ether, ethylene glycol hexyl ether, triethylene glycol methyl ether, triethylene glycol ethyl ether, and diethylene glycol butyl ether.

7. The composition according to claim 1, characterized in that, The composition further includes an auxiliary agent selected from one or more of polymerization inhibitors, surfactants, antioxidants, and chain transfer agents.

8. The composition according to claim 7, characterized in that, The total weight of the additives shall not exceed 3% of the total weight of the composition.

9. The composition according to claim 1, characterized in that, At 25°C, the viscosity of the composition is 15-40 cps and the surface tension is 20-32 mN / m; at 30-70°C, the viscosity of the composition is 9-15 cps and the surface tension is 20-32 mN / m.

10. A method for preparing the composition according to any one of claims 1 to 9, characterized in that, Includes the following steps: Under the condition of avoiding photo-induced polymerization reactions of each component, water-soluble monofunctional photocurable monomer, non-reactive polymer and aqueous solvent are mixed evenly to obtain the first mixture; A photoinitiator was added to the first mixture, and after mixing evenly, a second mixture was obtained. The second mixture is filtered, and the filtrate is collected to obtain the composition.

11. A 3D inkjet printing method, characterized in that, The printing process includes: using a 3D inkjet printing apparatus to print a support structure using the composition for 3D inkjet printing support structure according to any one of claims 1 to 9; wherein the 3D inkjet printing apparatus includes an inkjet printhead.

12. The method according to claim 11, characterized in that, It also includes printing target 3D objects under the support of the support structure.

13. A support structure, characterized in that, The support structure is printed using a composition according to any one of claims 1 to 9 for 3D inkjet printing support structures.

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