High transparency uv curable ink and method for preparing the same

Abstract

This invention belongs to the field of ink technology, specifically relating to a high-transparency UV-curable ink and its preparation method. By weight, it comprises the following raw materials: 40-50 parts modified polymethyl methacrylate resin, 20-30 parts polyurethane acrylate resin, 15-25 parts reactive diluent, 2-7 parts photoinitiator, 1.5-2.5 parts dispersant, 1-2 parts coupling agent, 0.5-1 part leveling agent, and 0.5-1 part defoamer. The UV-curable ink prepared by this invention can increase ink fluidity, cure quickly, and has high transparency.

Description

Technical Field

[0001] This invention belongs to the field of ink technology, specifically relating to a high-transparency UV-curable ink and its preparation method. Background Technology

[0002] UV curing technology has developed rapidly worldwide due to its advantages such as fast curing speed, high safety, low energy consumption, and convenient operation, and has been gradually applied to various fields such as electronics, printing, construction, decoration, and chemicals.

[0003] With the increasing awareness of environmental protection, UV curing technology has developed rapidly in the ink industry and is being used more and more frequently. Compared with traditional solvent-based inks, UV inks do not contain volatile solvents, are highly environmentally friendly, have less impact on the human body, and the thickness of the cured film is less affected by the environment. In addition, UV inks have a short curing time, which shortens printing time and improves production efficiency. Moreover, UV ink printed products have better physical and chemical properties and are suitable for printing high-precision products such as electronic communications, optical discs, and automotive parts. However, commonly used UV curing inks may have problems such as poor abrasion resistance and poor light transmittance of printed products.

[0004] Patent CN105199476B discloses a UV-curable transparent insulating ink, comprising the following components: epoxy acrylate resin, polyurethane acrylate resin, reactive diluent, photoinitiator, coupling agent, defoamer, leveling agent, and thickener. This UV-curable transparent insulating ink has advantages such as low cost, high transparency, strong adhesion, and good insulation; however, this invention does not involve research on curing rate.

[0005] Patent CN103483905A discloses a UV-curable ink and its preparation method, comprising the following components: non-isocyanate polyurethane acrylate oligomer, epoxy acrylate oligomer, reactive diluent, photoinitiator, nano-silica, additives, and pigments. This UV-curable ink is environmentally friendly, can be rapidly cured by light, and possesses good gloss, excellent adhesion, mechanical properties, and oil resistance. However, this invention does not consider the dispersibility issues of the pigments and nano-silica.

[0006] Therefore, there is an urgent need to prepare a UV-curable ink with fast curing rate and good dispersibility of each component. Summary of the Invention

[0007] To overcome the shortcomings of the prior art, the present invention provides a high-transparency UV-curable ink with a fast curing rate, good fluidity, and high surface hardness after curing.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] The first aspect of this invention provides a high-transparency UV-curable ink, comprising, by weight, the following raw materials: 40-50 parts of modified polymethyl methacrylate resin, 20-30 parts of polyurethane acrylate resin, 15-25 parts of reactive diluent, 2-7 parts of photoinitiator, 1.5-2.5 parts of dispersant, 1-2 parts of coupling agent, 0.5-1 part of leveling agent, and 0.5-1 part of defoamer.

[0010] In some embodiments, the method for preparing the modified polymethyl methacrylate resin includes the following steps:

[0011] (1) Add 2,6-dihydroxybenzoic acid, cinnamyl alcohol, and sulfuric acid solution to toluene, stir at 70-80℃ for 6-7 h, then add 1-methylcyclopentanecarboxylic acid, continue stirring for 6-7 h, and rotary evaporate to obtain the compound;

[0012] (2) Add the compound obtained in step (1), methyl methacrylate, and initiator to the reaction vessel, stir at 70-80℃, control the weight average molecular weight to be 2500-3500, and dry to obtain modified polymethyl methacrylate resin.

[0013] Preferably, the concentration of the sulfuric acid solution is 85-95 wt%.

[0014] In some embodiments, the mass ratio of 2,6-dihydroxybenzoic acid, cinnamyl alcohol, and 1-methylcyclopentanecarboxylic acid in step (1) is 1:(0.9-1.1):(0.9-1.2).

[0015] Polymethyl methacrylate resin has good transparency and environmental friendliness, and can be used in many fields, but it has low surface hardness and is easily scratched. Modification of polymethyl methacrylate (PMMA) resin is often necessary. However, while conventional modifiers can improve the surface hardness of PMMA resin, they may reduce its transparency. This invention synthesizes a compound using 2,6-dihydroxybenzoic acid, cinnamyl alcohol, and 1-methylcyclopentane carboxylic acid in a specific ratio to prepare PMMA resin. This improves the surface hardness of PMMA resin without reducing its transparency. This is because the benzene ring and cyclopentane structure increase the surface hardness of PMMA, and the resulting compound may have good compatibility with PMMA. Furthermore, by limiting the mass ratio and feeding order of 2,6-dihydroxybenzoic acid, cinnamyl alcohol, and 1-methylcyclopentane carboxylic acid, the compound prepared by first reacting 2,6-dihydroxybenzoic acid with cinnamyl alcohol has benzene ring structures at both ends of the double bond. Then, it reacts with 1-methylcyclopentane carboxylic acid. The large steric hindrance effect of the benzene ring and cyclopentane reduces the self-polymerization of the compound, and the good compatibility of the resulting compound with PMMA promotes their polymerization without affecting the transparency.

[0016] In some embodiments, the mass ratio of the compound to methyl methacrylate in step (2) is (0.1-0.3):1.

[0017] In some embodiments, the viscosity of the modified polymethyl methacrylate resin obtained in step (2) is 4000-5000 mPa·s.

[0018] This invention increases the surface hardness of polymethyl methacrylate (PMMA) without reducing its transparency by limiting the mass ratio of the compound and PMMA; by limiting the viscosity of the modified PMMA resin to create a synergistic effect with the reactive diluent, the ink can be mixed evenly, improving its fluidity, which in turn helps to increase the curing rate and improve the printing effect.

[0019] In some embodiments, the preparation method of the dispersant includes the following steps: adding isoeugenol and 4-oxoisophorone to a reaction vessel, stirring for 8-12 minutes to obtain a mixture, then adding ammonium persulfate and deionized water, heating to 75-85°C, stirring for 1-2 hours, then adding 2-(trifluoromethyl)acrylic acid, stirring for 3-5 hours, cooling to room temperature, filtering, washing, drying, and grinding to obtain the dispersant.

[0020] In some embodiments, the mass ratio of isoeugenol, 4-oxoisophorone, and 2-(trifluoromethyl)acrylic acid is 1:(1-1.2):(0.9-1.1).

[0021] This invention prepares a dispersant with excellent dispersing effect. First, isoeugenol and 4-oxoisophorone are reacted, followed by the addition of 2-(trifluoromethyl)acrylic acid. By controlling the order of addition and the mass ratio of isoeugenol, 4-oxoisophorone, and 2-(trifluoromethyl)acrylic acid, the prepared dispersant has hydrophilic groups on both sides, which enhances the anchoring effect. The synergistic effect of the long alkane chain segments and steric hindrance of the ring structure improves the dispersibility of each component in the ink, resulting in a uniform distribution of components and increased ink transparency. Simultaneously, the presence of phenolic hydroxyl groups enhances the ink's antioxidant properties, making the ink more stable.

[0022] In some embodiments, the reactive diluent is a multifunctional acrylate monomer.

[0023] Preferably, the reactive diluent is any one or more of tripropylene glycol diacrylate, pentaerythritol triacrylate, 1,6-hexanediol diacrylate, and dipropylene glycol diacrylate.

[0024] More preferably, the reactive diluent is pentaerythritol triacrylate.

[0025] In some embodiments, the photoinitiator is 1-hydroxycyclohexylphenyl ketone and 2-dimethylamino-2-benzyl-1-[4-(4-morpholino)phenyl]-1-butanone, in a mass ratio of (2.5-3.5):1.

[0026] In some embodiments, the coupling agent is γ-aminopropylmethyldiethoxysilane.

[0027] A second aspect of this invention provides a method for preparing a high-transparency UV-curable ink, comprising the following steps:

[0028] S1. Stir the modified polymethyl methacrylate resin, polyurethane acrylate resin, reactive diluent, photoinitiator, dispersant, coupling agent, leveling agent and defoamer for 10-20 minutes to obtain a mixture;

[0029] S2. Grind the mixture obtained in step S1 for 60-80 minutes to obtain a high-transparency UV-curable ink.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] 1. This invention prepares a UV-curable ink by mixing modified polymethyl methacrylate, polyurethane acrylate resin, dispersant and other additives, which can increase the ink's fluidity, improve the curing rate, and have high transparency.

[0032] 2. This invention synthesizes a compound by combining 2,6-dihydroxybenzoic acid, cinnamyl alcohol, and 1-methylcyclopentane carboxylic acid in a specific ratio, and uses it to prepare polymethyl methacrylate resin. On the one hand, the benzene ring and cyclopentane structure increase the surface hardness of polymethyl methacrylate. On the other hand, the large steric hindrance effect of the benzene ring and cyclopentane reduces self-polymerization. The ester groups generated after the reaction have good compatibility with methyl methacrylate, which promotes the polymerization of the two without affecting the transparency.

[0033] 3. This invention provides a dispersant with excellent dispersing effect obtained through isoeugenol, 4-oxoisophorone, and 2-(trifluoromethyl)acrylic acid. First, isoeugenol and 4-oxoisophorone are reacted, followed by the addition of 2-(trifluoromethyl)acrylic acid. By controlling the order of addition and the mass ratio of isoeugenol, 4-oxoisophorone, and 2-(trifluoromethyl)acrylic acid, the prepared dispersant exhibits enhanced anchoring effect through hydrophilic groups on both sides. This, combined with the steric hindrance effect of the long alkane chain segments and cyclic structure, improves dispersibility, resulting in uniform distribution of components in the ink, increased ink transparency, and enhanced antioxidant properties due to the presence of phenolic hydroxyl groups, thus making the ink more stable. Detailed Implementation

[0034] The present invention will be described below with reference to specific embodiments. It should be noted that the following embodiments and comparative examples are examples of the present invention and are used only to illustrate the invention, not to limit it. Other combinations and various modifications within the scope of the present invention can be made without departing from the spirit or scope of the invention.

[0035] To facilitate the implementation of this invention by those skilled in the art, the following description is provided regarding some of the raw materials and manufacturers used in the embodiments and comparative examples: The compounds and related reagents used in this invention are all commercially available. Specifically, the polyurethane acrylic resin was purchased from Shanghai Zhenlishi Network Technology Co., Ltd., model EBECRYL270; the defoamer was purchased from Dongguan Haoyouduo New Materials Co., Ltd., model BYK-A530; the leveling agent was purchased from Dongguan Huazhiyuan Chemical Co., Ltd., model BYK-315; and the dispersant was purchased from Guangzhou Haoliangda International Trade Co., Ltd., model BYK111.

[0036] Preparation Example 1

[0037] The preparation method of modified polymethyl methacrylate resin-1 includes the following steps:

[0038] (1) Add 10g of 2,6-dihydroxybenzoic acid, 10g of cinnamyl alcohol, and 2ml of 90wt% sulfuric acid aqueous solution to 50ml of toluene, stir at 75℃ for 6.5h, then add 11g of 1-methylcyclopentanecarboxylic acid, continue stirring for 6.5h, and rotary evaporate to obtain the compound;

[0039] (2) Add 2g of the compound obtained in step (1), 10g of methyl methacrylate and 0.1g of azobisisobutyronitrile to the reaction vessel, stir at 75°C and dry to obtain modified polymethyl methacrylate resin-1 with a weight average molecular weight of 2982 and a viscosity of 4657mPa·s.

[0040] Preparation Example 2

[0041] The preparation method of modified polymethyl methacrylate resin-2 is the same as that in preparation example 1, except that the amount of 1-methylcyclopentane carboxylic acid added is 7g.

[0042] Preparation Example 3

[0043] The preparation method of modified polymethyl methacrylate resin-3 is the same as that in preparation example 1, except that the amount of cinnamyl alcohol added is 13g.

[0044] Preparation Example 4

[0045] The preparation method of modified polymethyl methacrylate resin-4 is the same as that in preparation example 1, except that the amount of compound added in step (2) is 5g.

[0046] Preparation Example 5

[0047] The preparation method of modified polymethyl methacrylate resin-5 is the same as that in preparation example 1, except that the viscosity is 5721 mPa·s.

[0048] Preparation Example 6

[0049] The preparation method of polymethyl methacrylate resin includes the following steps: 10g of methyl methacrylate and 0.1g of azobisisobutyronitrile are added to a reaction vessel, stirred and reacted at 75°C, and dried to obtain polymethyl methacrylate resin with a weight-average molecular weight of 3211 and a viscosity of 4407mPa·s.

[0050] Preparation Example 7

[0051] The preparation method of dispersant-1 includes the following steps: 1g of isoeugenol and 1.1g of 4-oxoisophorone are added to a reaction vessel and stirred for 10min to obtain a mixture. Then, 0.01g of ammonium persulfate and 10g of deionized water are added, heated to 80℃ and stirred for 1.5h. Then, 1g of 2-(trifluoromethyl)acrylic acid is added and stirred for 4h. After cooling to room temperature, the mixture is filtered, washed, dried, and ground to obtain dispersant-1.

[0052] Preparation Example 8

[0053] The preparation method of dispersant-2 is the same as that of preparation example 7, except that the amount of 2-(trifluoromethyl)acrylic acid added is 2g.

[0054] Example 1

[0055] A high-transparency UV-curable ink, by weight, comprises the following raw materials: 45 parts modified polymethyl methacrylate resin-1, 25 parts polyurethane acrylate resin, 20 parts pentaerythritol triacrylate, 5 parts photoinitiator, 12 parts dispersant, 1.5 parts γ-aminopropylmethyldiethoxysilane, 0.8 parts leveling agent BYK-315, and 0.8 parts defoamer BYK-A530.

[0056] The photoinitiator is 1-hydroxycyclohexylphenyl ketone and 2-dimethylamino-2-benzyl-1-[4-(4-morpholino)phenyl]-1-butanone, with a mass ratio of 3:1.

[0057] The preparation method of the high-transparency UV-curable ink in this embodiment includes the following steps:

[0058] S1. Mix the modified polymethyl methacrylate resin-1, polyurethane acrylate resin, pentaerythritol triacrylate, photoinitiator, dispersant-1, γ-aminopropylmethyldiethoxysilane, leveling agent BYK-315 and defoamer BYK-A530 for 15 min to obtain a mixture.

[0059] S2. The mixture obtained in step S1 is ground by a three-roll mill for 70 minutes to obtain a high-transparency UV-curable ink.

[0060] Example 2

[0061] A high-transparency UV-curable ink, by weight, comprises the following raw materials: 40 parts modified polymethyl methacrylate resin-1, 20 parts polyurethane acrylate resin, 15 parts pentaerythritol triacrylate, 2 parts photoinitiator, 11.5 parts dispersant-1, 1 part γ-aminopropylmethyldiethoxysilane, 0.5 parts leveling agent BYK-315, and 0.5 parts defoamer BYK-A530.

[0062] The photoinitiator is 1-hydroxycyclohexylphenyl ketone and 2-dimethylamino-2-benzyl-1-[4-(4-morpholino)phenyl]-1-butanone, with a mass ratio of 2.5:1.

[0063] The preparation method of the high-transparency UV-curable ink in this embodiment includes the following steps:

[0064] S1. Mix the modified polymethyl methacrylate resin-1, polyurethane acrylate resin, pentaerythritol triacrylate, photoinitiator, dispersant-1, γ-aminopropylmethyldiethoxysilane, leveling agent BYK-315 and defoamer BYK-A530 for 10 min to obtain a mixture.

[0065] S2. The mixture obtained in step S1 is ground by a three-roll mill for 60 minutes to obtain a high-transparency UV-curable ink.

[0066] Example 3

[0067] A high-transparency UV-curable ink, by weight, comprises the following raw materials: 150 parts modified polymethyl methacrylate resin, 30 parts polyurethane acrylate resin, 25 parts pentaerythritol triacrylate, 7 parts photoinitiator, 12.5 parts dispersant, 2 parts γ-aminopropylmethyldiethoxysilane, 1 part leveling agent BYK-315, and 1 part defoamer BYK-A530.

[0068] The photoinitiator is 1-hydroxycyclohexylphenyl ketone and 2-dimethylamino-2-benzyl-1-[4-(4-morpholino)phenyl]-1-butanone, with a mass ratio of 3.5:1.

[0069] The preparation method of the high-transparency UV-curable ink in this embodiment includes the following steps:

[0070] S1. Mix the modified polymethyl methacrylate resin-1, polyurethane acrylate resin, pentaerythritol triacrylate, photoinitiator, dispersant-1, γ-aminopropylmethyldiethoxysilane, leveling agent BYK-315 and defoamer BYK-A530 for 20 min to obtain a mixture.

[0071] S2. The mixture obtained in step S1 is ground by a three-roll mill for 80 minutes to obtain a high-transparency UV-curable ink.

[0072] Example 4

[0073] A high-transparency UV-curable ink and its preparation method are disclosed. The specific implementation method is the same as that in Example 1, except that the modified polymethyl methacrylate resin-1 is replaced by an equal amount of modified polymethyl methacrylate resin-2.

[0074] Example 5

[0075] A high-transparency UV-curable ink and its preparation method are disclosed. The specific implementation method is the same as that in Example 1, except that the modified polymethyl methacrylate resin-1 is replaced by an equal amount of modified polymethyl methacrylate resin-3.

[0076] Example 6

[0077] A high-transparency UV-curable ink and its preparation method are disclosed. The specific implementation method is the same as that in Example 1, except that the modified polymethyl methacrylate resin-1 is replaced by an equal amount of modified polymethyl methacrylate resin-4.

[0078] Example 7

[0079] A high-transparency UV-curable ink and its preparation method are disclosed. The specific implementation method is the same as that in Example 1, except that the modified polymethyl methacrylate resin-1 is replaced by an equal amount of modified polymethyl methacrylate resin-5.

[0080] Example 8

[0081] A high-transparency UV-curable ink and its preparation method are described. The specific implementation method is the same as in Example 1, except that dispersant-1 is replaced by dispersant-2 in equal amounts.

[0082] Comparative Example 1

[0083] A high-transparency UV-curable ink and its preparation method are disclosed. The specific implementation method is the same as that in Example 1, except that the modified polymethyl methacrylate resin-1 is replaced with an equal amount of polymethyl methacrylate resin.

[0084] Comparative Example 2

[0085] A high-transparency UV-curable ink and its preparation method are described. The specific implementation method is the same as that in Example 1, except that dispersant-1 is replaced by dispersant BYK111 in equal amounts.

[0086] Performance testing

[0087] 1. Curing time

[0088] Take 0.5 ml of the high-transparency UV-curable ink prepared in each example and comparative example, apply it to coated paper, and irradiate it with a UVA-340 lamp until it is completely cured. The method for judging the complete curing time is as follows: select a 500g weight with a flat bottom, place 3 cotton fibers on the surface of the cured ink, press the weight on the cotton fibers for 2 minutes, and remove the weight. If the cotton fibers do not stick to the ink surface, it means that it is completely cured. Record the irradiation time as the complete curing time.

[0089] 2. Liquidity

[0090] The flowability of UV-curable inks was tested according to the national standard GB / T 13217.4-2020.

[0091] 3. Light transmittance

[0092] The high-transparency UV-curable inks prepared in each embodiment and comparative example were coated on ITO glass with a thickness of 30 μm. They were then irradiated with a UVA-340 lamp until fully cured. The light transmittance of the cured film was tested using a transmittance meter, and the transmittance was recorded.

[0093] 4. Hardness

[0094] The high-transparency UV-curable inks prepared in each embodiment and comparative example were coated onto glass and cured. The specific implementation method is the same as the light curing rate test. The surface hardness was tested by placing the hardness tester and the sample to be tested flat on a horizontal platform. The lead of pencils of different hardnesses was cut open with a blade so that the protruding part of the lead was about 4mm. The lead was then smoothed with sandpaper. The pencil was then inserted into the instrument, and the hardness tester was pushed forward 2cm from back to front. The hardness tester was removed, and the pencil marks were erased with an eraser. The hardness was then determined, and the sample to be tested was observed for scratches. For example, if there were no scratches on the surface of an H pencil, there were no scratches on the surface of a 2H pencil, and there were scratches on the surface of a 3H pencil, then the hardness grade of the sample to be tested was 2H.

[0095] The test results are shown in Table 1.

[0096] Table 1

[0097] Example 1 1.8 19.6 99 3H Example 2 2.0 19.3 99 3H Example 3 1.9 19.5 99 3H Example 4 2.1 17.2 97 3H Example 5 2.5 18.8 97 3H Example 6 2.3 19.1 98 2H Example 7 3.0 16.6 97 3H Example 8 2.8 17.5 97 2H Comparative Example 1 3.9 16.9 97 2H Comparative Example 2 3.2 15.2 97 3H

[0098] A comparison of the data from Examples 1-3 in Table 1 shows that the ink has high surface hardness, good fluidity, transparency, and fast curing speed. A comparison of Examples 4 and 5 with Example 1 shows that changes in the ratio of 2,6-dihydroxybenzoic acid, cinnamyl alcohol, and 1-methylcyclopentanecarboxylic acid may affect the copolymerization of the compound with methyl methacrylate, resulting in a decrease in both the transparency and fluidity of the ink. A comparison of Example 6 with Example 1 shows that changes in the ratio of the compound and methyl methacrylate in modified polymethyl methacrylate resin-4 lead to a decrease in the hardness of the ink. Examples 7 and... As can be seen from the comparison of Example 1, the change in viscosity of the modified polymethyl methacrylate resin leads to an increase in the curing time of the ink, and a decrease in both fluidity and transparency. As can be seen from the comparison of Example 8 and Example 1, the change in the ratio of isoeugenol, 4-oxoisophorone, and 2-(trifluoromethyl)acrylic acid may lead to a decrease in the dispersibility of the ink, resulting in a decrease in all properties of the ink. As can be seen from the comparison of Comparative Example 1 and Example 1, the ink using unmodified polymethyl methacrylate resin has a decrease in all properties. As can be seen from the comparison of Comparative Example 2 and Example 1, the ink using commercially available dispersants has poorer fluidity and reduced transparency.

[0099] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A high-transparency UV-curable ink, characterized in that, By weight, it contains the following raw materials: 40-50 parts modified polymethyl methacrylate resin, 20-30 parts polyurethane acrylate resin, 15-25 parts reactive diluent, 2-7 parts photoinitiator, 1.5-2.5 parts dispersant, 1-2 parts coupling agent, 0.5-1 part leveling agent and 0.5-1 part defoamer.

2. The high-transparency UV-curable ink according to claim 1, characterized in that, The preparation method of the modified polymethyl methacrylate resin includes the following steps: (1) Add 2,6-dihydroxybenzoic acid, cinnamyl alcohol, and sulfuric acid solution to toluene, stir at 70-80℃ for 6-7 h, then add 1-methylcyclopentanecarboxylic acid, continue stirring for 6-7 h, and rotary evaporate to obtain the compound; (2) Add the compound obtained in step (1), methyl methacrylate, and initiator to the reaction vessel, stir at 70-80℃, control the weight average molecular weight to be 2500-3500, and dry to obtain modified polymethyl methacrylate resin.

3. The high-transparency UV-curable ink according to claim 2, characterized in that, In step (1), the mass ratio of 2,6-dihydroxybenzoic acid, cinnamyl alcohol, and 1-methylcyclopentanecarboxylic acid is 1:(0.9-1.1):(0.9-1.2).

4. The high-transparency UV-curable ink according to claim 2, characterized in that, In step (2), the mass ratio of the compound to methyl methacrylate is (0.1-0.3):

1.

5. The high-transparency UV-curable ink according to claim 1, characterized in that, The method for preparing the dispersant includes the following steps: adding isoeugenol and 4-oxoisophorone to a reaction vessel, stirring for 8-12 minutes to obtain a mixture, then adding ammonium persulfate and deionized water, heating to 75-85℃, adding 2-(trifluoromethyl)acrylic acid, stirring for 3-5 hours, cooling to room temperature, filtering, washing, drying, and grinding to obtain the dispersant.

6. The high-transparency UV-curable ink according to claim 5, characterized in that, The mass ratio of isoeugenol, 4-oxoisophorone, and 2-(trifluoromethyl)acrylic acid is 1:(1-1.2):(0.9-1.1).

7. The high-transparency UV-curable ink according to claim 1, characterized in that, The reactive diluent is a multifunctional acrylate monomer.

8. The high-transparency UV-curable ink according to claim 1, characterized in that, The photoinitiator is 1-hydroxycyclohexylphenyl ketone and 2-dimethylamino-2-benzyl-1-[4-(4-morpholino)phenyl]-1-butanone, with a mass ratio of (2.5-3.5):

1.

9. The method for preparing the high-transparency UV-curable ink according to claim 1, characterized in that, The coupling agent is γ-aminopropylmethyldiethoxysilane.

10. A high-transparency UV-curable ink according to any one of claims 1-9, characterized in that, Includes the following steps: S1. Stir the modified polymethyl methacrylate resin, polyurethane acrylate resin, reactive diluent, photoinitiator, dispersant, coupling agent, leveling agent and defoamer for 10-20 minutes to obtain a mixture; S2. Grind the mixture obtained in step S1 for 60-80 minutes to obtain a high-transparency UV-curable ink.