Ureido-containing uv-curable polymeric compositions and pressure sensitive adhesive tapes and methods of making

Abstract

The present application relates to a urea group-containing UV curing high polymer composition and pressure-sensitive adhesive tape and a preparation method, the high polymer composition comprises the following mass parts of raw materials: 100 parts of polyurea acrylate prepolymer resin, 1-2 parts of a photoinitiator, 1-5 parts of a curing agent and 1-5 parts of a plasticizer; the polyurea acrylate prepolymer resin is obtained by copolymerization of the following mass parts of monomers: 6-10 parts of a urea group acrylate functional monomer, 60-80 parts of a soft monomer, 10-20 parts of a hard monomer, 1-5 parts of an unsaturated carboxylic acid and 10-15 parts of a hydroxyl-containing acrylate monomer; the urea group acrylate functional monomer contains two or more carbon-carbon unsaturated double bonds, two or more urea groups and one or more functional groups, and the functional groups are selected from at least one of a hydroxyl group, an epoxy group, a carboxyl group and an amino group. The urea group-containing UV curing high polymer composition provided by the present application has excellent UV tack reduction performance, and also has high temperature resistance.

Description

Technical Field

[0001] This invention belongs to the field of chip protective film technology, specifically relating to a urea-based UV-curable polymer composition, a pressure-sensitive tape containing the same composition, and a preparation method thereof. Background Technology

[0002] UV-resistant tape has high adhesion and good adhesion before UV irradiation. When separation is required, the adhesion is greatly reduced after a short period of UV irradiation, making it easy to tear off without leaving residue. It is widely used in semiconductor wafer cutting, semiconductor wafer grinding and other fields, and plays a role in fixing, protecting and bonding in the semiconductor wafer manufacturing process. However, some processes involve high-temperature processes in wafer cutting and grinding, and ordinary UV-resistant tape is difficult to meet the requirements of this process.

[0003] Most UV anti-tack adhesive formulations on the market are made by mixing hydroxyl- and carboxyl-containing unsaturated acrylate polymers, multifunctional acrylate oligomers, photoinitiators, and curing agents. However, this method has limited compatibility and leaves residues after cross-linking, making it difficult to apply to high-temperature processes.

[0004] Since the late 1980s, when the first patent for UV-curable peelable pressure-sensitive adhesive tape specifically for chip processing appeared, most widely used anti-tack adhesives are composed of acrylate copolymers. For example, Seung-Woo Lee et al. proposed introducing 3-trimethoxysilane propylene acrylate into anti-tack adhesives. The introduction of silane groups into the anti-tack adhesive improves the adhesion of the anti-tack adhesive layer to the wafer, reduces resin creep during wafer grinding, and improves the stability of the adhesive layer. However, the introduction of silane groups reduces the adhesion of the adhesive layer to the substrate, and it is easy to leave adhesive residue after UV irradiation. In terms of the production and research of UV anti-tack adhesives in China, patent CN109825200A describes the use of special photosensitive groups grafted onto the main resin during the production of anti-tack adhesives. After UV irradiation, rapid peeling can be achieved. However, the introduction of rigid photosensitive groups into the side chains of the photosensitive resin chain increases the resin hardness and reduces wettability. The resin's adhesion to the substrate is reduced, and after UV irradiation, it is easy to detach from the substrate and adhere to the wafer surface, causing adhesive residue and affecting processing.

[0005] CN111057474A discloses an adhesive for UV-resistant anti-tack films, comprising acrylate resin, tackifying resin, and multifunctional monomers, wherein the multifunctional monomers are acrylate monomers containing urea groups, such as triallyl isocyanate and 1,3-diallyl urea. It uses acrylate monomers containing urea groups, which have high polarity, improving adhesive strength. Simultaneously, the urea groups can react with isocyanates, increasing the degree of crosslinking and reducing adhesive residue. However, after UV irradiation treatment at temperatures above 100°C, the peel strength significantly increases, while the UV anti-tack performance decreases, making it unsuitable for processes involving high temperatures.

[0006] Therefore, developing a non-stick tape with high peel strength before UV irradiation, rapid reduction of peel strength after irradiation, easy peeling, no residue, and high temperature resistance is an urgent problem to be solved in this field. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a high-temperature resistant urea-containing UV-curable polymer composition, and to provide one or more urea-containing functional acrylate UV-curable pressure-sensitive tapes and their preparation methods. The urea monomer is a functional monomer containing unsaturated double bonds, which improves the stability of the resin system and enhances adhesion in polyurea-acrylic resin systems. In particular, the presence of the urea group can significantly improve resin wettability, thereby increasing adhesion. Furthermore, after UV irradiation, the unsaturated double bonds in the functional monomer undergo self-crosslinking, achieving a reduced-tack effect and making it easier to peel off. Before UV irradiation, the tape exhibits high peel strength, good fixation, and good high-temperature resistance.

[0008] In a first aspect, the present invention provides a urea-containing UV-curable polymer composition comprising the following raw materials in parts by weight: 100 parts of polyurea acrylate prepolymer resin, 1-2 parts of photoinitiator, 1-5 parts of curing agent, and 1-5 parts of plasticizer; wherein the polyurea acrylate prepolymer resin is obtained by copolymerization of the following monomers in parts by weight: 6-10 parts of urea acrylate functional monomer, 60-80 parts of soft monomer, 10-20 parts of hard monomer, 1-5 parts of unsaturated carboxylic acid, and 10-15 parts of hydroxyl-containing acrylate monomer; wherein the urea acrylate functional monomer contains two or more carbon-carbon unsaturated double bonds, two or more urea groups, and one or more functional groups, wherein the functional groups are selected from at least one of hydroxyl, epoxy, carboxyl, and amino groups.

[0009] The high-temperature resistance refers to the ability to maintain good UV de-adhesion properties even after high-temperature treatment at 120-180℃ (e.g., 120℃, 150℃, 180℃), i.e., after treatment at 120-180℃ for 1-2 hours, the peel strength after UV irradiation is ≤15gf / 25mm.

[0010] In addition to the monomers mentioned above, the raw materials for preparing polyurea acrylate prepolymer resin also include an initiator. The initiator is a peroxide initiator or an azo initiator, such as benzoyl peroxide. The amount of initiator added is 0.6-1.5 wt% of the total monomer mass, preferably 0.9-1.1 wt%. The total monomer mass is the sum of the masses of the urea acrylate functional monomer, soft monomer, hard monomer, unsaturated carboxylic acid, and hydroxyl-containing acrylate monomer.

[0011] Further, the ultraviolet photoinitiator is at least one of benzoin diethyl ether, ethyl 2,4,6-trimethylbenzoylphenylphosphonate, and phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide; the curing agent is at least one of aziridine curing agents and isocyanates; the plasticizer is selected from at least one of sebacic acid series, adipic acid series, and phthalic acid series, such as at least one of dioctyl sebacate, dioctyl adipate, and dioctyl phthalate.

[0012] Further, the soft monomer is selected from at least one of isooctyl acrylate, butyl acrylate, and hexyl acrylate; the hard monomer is selected from at least one of vinyl acetate, methyl (meth)propionate, and ethyl (meth)acrylate; the unsaturated carboxylic acid is selected from at least one of acrylic acid and maleic acid; and the hydroxyl-containing acrylate monomer is selected from at least one of hydroxyethyl (meth)acrylate and hydroxypropyl (meth)acrylate.

[0013] Furthermore, the urea acrylate functional monomer is prepared by a method comprising the following steps: reacting hydroxy acrylate and isophorone diisocyanate in the presence of a polymerization inhibitor and a catalyst, followed by adding a multifunctional compound to continue the reaction, thereby obtaining the urea acrylate functional monomer; the multifunctional compound has two or more functional groups that can react with isocyanate (NCO) groups, such as hydroxyl, amino, and carboxyl groups.

[0014] Furthermore, the hydroxy acrylate is selected from at least one of hydroxyethyl methacrylate, hydroxypropyl methacrylate, and hydroxybutyl methacrylate; isophorone diisocyanate has two NCO groups, but with different reactivity. Utilizing this characteristic of isophorone diisocyanate, the hydroxy acrylate reacts with one NCO group on the isophorone diisocyanate, and the resulting product retains one NCO group; the multifunctional compound is at least one of 3-amino-1,2-propanediol, 1,3-diamino-2-hydroxypropane, 1,11-diaminoundecane-6-ol, 2,6-diamino-1-hexanol, 2,3-diamino-1-butanol, 2,2-di(aminomethyl)propane-1,3-diol, and 1,4-diamino-2,3-butanediol.

[0015] The polymerization inhibitor and catalyst are not particularly limited. Any polymerization inhibitor conventionally used in the art to prevent the polymerization of carbon-carbon unsaturated double bonds, or a catalyst used for the reaction of NCO with hydroxyl groups or NCO with amino groups, is acceptable. For example, the polymerization inhibitor may be selected from hydroquinone, and the amount of the inhibitor is 0.5-1 wt% of the mass of the hydroxyacrylate; the catalyst may be an organotin compound, such as dibutyltin dilaurate, and the amount of the catalyst is 1-2 wt% of the mass of the hydroxyacrylate.

[0016] Furthermore, the reaction of hydroxyacrylate and isophorone diisocyanate is carried out at 0-10℃, with isophorone diisocyanate being slowly added to the system, for example, within 1-3 hours, and then kept at the temperature for 3-5 hours after addition; the reaction is continued at 40-50℃ with the addition of a polyfunctional compound, with the polyfunctional compound being slowly added to the system, for example, within 1-3 hours, and then kept at the temperature for 3-5 hours after addition.

[0017] Furthermore, the urea-acrylate functional monomer is prepared by a method comprising the following steps: 100 parts by mass of hydroxyacrylate is dissolved in 2-4 times its mass of a first organic solvent; a polymerization inhibitor and a catalyst are added; isophorone diisocyanate is added dropwise at a controlled temperature of 0-10°C over 1-3 hours; the reaction is maintained at this temperature for 3-5 hours; then, a multifunctional compound is slowly added at a controlled temperature of 40-50°C over 1-3 hours; the reaction is maintained at this temperature for 3-5 hours; the solvent and unreacted monomer are removed by vacuum distillation to obtain the urea-acrylate functional monomer. Preferably, the first organic solvent is selected from at least one of acetone, butanone, tetrahydrofuran, and ethyl acetate. The molar ratio of hydroxyacrylate, isophorone diisocyanate, and the multifunctional compound is 1:0.9-1:1-1.1.

[0018] Furthermore, the polyurea acrylate prepolymer resin is prepared by a method comprising the following steps:

[0019] (S1) Mix 60-80 parts of soft monomer, 10-20 parts of hard monomer, and 1-5 parts of unsaturated carboxylic acid evenly to form a mixed monomer. Take 25-35 wt% of the mixed monomer and add 0.3-0.35 wt% of initiator based on the total mass of the monomers to form Agent A. Take 30-40 wt% of the mixed monomer and add 0.4-0.5 wt% of initiator based on the total mass of the monomers to form Agent B. Add 6-10 parts of urea acrylate functional monomer and 10-15 parts of hydroxyl-containing acrylate monomer to the remaining mixed monomer, and then add 0.2-3 wt% of initiator based on the total mass of the monomers to form Agent C.

[0020] The total mass of the monomers is the sum of the masses of the urea acrylate functional monomers, soft monomers, hard monomers, unsaturated carboxylic acids, and hydroxyl-containing acrylate monomers.

[0021] (S2) Under a protective atmosphere, agent A is added to the second organic solvent, the temperature is raised to 65-70℃, and the reaction is maintained for 1-2 hours; the temperature is raised to 80-85℃, agent B is added dropwise, and the addition is completed within 1-2 hours, and the reaction is maintained for 0.5-1 hours; agent C is added dropwise, and the addition is completed within 1-2 hours, and the reaction is maintained for 1-2 hours.

[0022] (S3) Cool the reaction system to 40-50℃, add a second organic solvent to adjust the solid content to 30-40%, and obtain a polyurea acrylate prepolymer resin solution.

[0023] Further, the second organic solvent is selected from at least one of ethyl acetate, propyl acetate, and butyl acetate. The amount of the second organic solvent added is 50-60 wt% of the total mass of agents A, B, and C.

[0024] The present invention also provides a UV-curable pressure-sensitive tape, which is composed of a polyester release film, a coating layer of the above-mentioned urea-based UV-curable polymer composition layer, and a base film.

[0025] Furthermore, the polyester release film is a PET polyester release film; the base film is selected from polyvinyl chloride film, polyolefin film (polyethylene film, polypropylene film). The thickness of the polyester release film is 35-45μm, the thickness of the urea-based UV adhesive is 10-20μm, and the thickness of the base film is 80-120μm.

[0026] The present invention also provides a method for preparing the UV-curable pressure-sensitive adhesive tape, comprising the following steps: uniformly coating a urea-based UV-curable polymer composition solution onto a polyester release film, prepolymerizing and removing the solvent by temperature gradient heating; then laminating the polyester release film coated with the urea-based UV-curable polymer composition and the base film together, and curing to obtain the UV-curable pressure-sensitive adhesive tape.

[0027] Furthermore, there is no particular limitation on the coating method of the urea-based UV-curable polymer composition solution, such as hang coating, roller coating, spray coating, or spin coating. In one specific embodiment of the present invention, roller coating is used with a linear speed of 5-30 m / min.

[0028] Furthermore, the temperature gradient is achieved by baking in 3-5 ovens, such as 4 ovens, with the temperature of section I being 75-85℃, section II being 90-100℃, section III being 105-120℃, and section IV being 90-100℃.

[0029] Furthermore, the compounding is carried out at 0.3-0.8 MPa, and the curing is carried out in a drying room at 45-60℃ for 48-72 hours.

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

[0031] I. This invention uses polyurea acrylate prepolymer resin to prepare a UV-curable pressure-sensitive adhesive. Since urea-containing monomers are functional monomers containing unsaturated double bonds, they improve the stability of the acrylic resin system and enhance adhesion. In particular, the presence of urea groups can greatly improve resin wettability, thereby increasing adhesion. Compared to traditional UV-curable acrylate monomers mixed with low molecular weight urea monomers or polyurethane two-component UV-curable pressure-sensitive adhesives, this invention exhibits better cohesion in the adhesive layer and better adhesion to the substrate surface, without causing contamination to the surface of the disc-cut product before or after UV irradiation. This results in materials containing the urea-containing UV-curable adhesive composition having high peel strength, and the tackiness decreases rapidly after UV irradiation. No additional UV-active monomers or oligomers are needed, eliminating the risk of residue. Furthermore, the urea-containing unsaturated acrylate adhesive improves the adhesion of the material to the substrate and also possesses high-temperature resistance and creep resistance.

[0032] II. Due to the strong polar monomer doping and the retention of double bonds and more hydroxyl and amino groups during the polymerization process, the polyurea acrylate prepolymer resin of the present invention provides crosslinking sites. As a matrix resin in the UV-curable pressure-sensitive adhesive, it results in strong initial adhesion of the cut tape and can play a good role in fixing the discs. When irradiated by UV light, the adhesive layer crosslinks and cures, and the adhesion of the tape decreases to a small value (peel force within 10gf / 25mm), making it easy to peel off. The cut discs can be picked up very well. Attached Figure Description

[0033] Figure 1 From left to right, these are the residual adhesives after being peeled off from Examples 1, 2, 1, and 2 after being treated at 150°C and irradiated with UV. Detailed Implementation

[0034] The embodiments given below are intended to further illustrate the present invention, but should not be construed as limiting the scope of protection of the present invention. Any non-essential improvements and adjustments made to the present invention by those skilled in the art based on the above description of the present invention still fall within the scope of protection of the present invention.

[0035] The curing agent L-75 was purchased from Bayer MaterialScience (China); the polyester plasticizer W-1040-S was purchased from D.E. Co., Ltd., Japan.

[0036] The polyester release film was purchased from Yangzhou Wanrun Optoelectronic Technology Co., Ltd., with the product name CT-2, thickness 36μm, and peel strength within 10gf / 25mm.

[0037] Preparation Example 1-1

[0038] At room temperature, 100 parts by mass of hydroxyethyl acrylate were added to 250 parts by mass of acetone, along with 0.5 parts by mass of hydroquinone and 1.25 parts by mass of dibutyltin dilaurate. Isophorone diisocyanate was added dropwise at 0-10℃, with a molar ratio of isophorone diisocyanate to hydroxyethyl acrylate of 1:1. The addition was completed over 3 hours, and the reaction was continued at 0-10℃ for another 3 hours. The temperature was then raised to 40℃, and 1,3-diamino-2-hydroxypropane was added dropwise, with a molar ratio of 1,3-diamino-2-hydroxypropane to hydroxyethyl acrylate of 1:1. The addition was completed over 2 hours, and the reaction was continued for another 3 hours. Afterward, acetone was removed by vacuum distillation to obtain urea-functionalized monomer 1.

[0039] Preparation Examples 1-2

[0040] The other conditions and procedures were the same as in Preparation Example 1-1, except that 1,3-diamino-2-hydroxypropane was replaced with an equimolar amount of 1,11-diaminoundecane-6-ol to obtain urea-functionalized monomer 2.

[0041] Preparation Examples 1-3

[0042] The other conditions and operations are the same as in Preparation Example 1-1, except that 1,3-diamino-2-hydroxypropane is replaced with an equimolar amount of 2,3-diamino-1-butanol to obtain urea-functionalized monomer 3.

[0043] Preparation Examples 1-4

[0044] The other conditions and operations are the same as in Preparation Example 1-1, except that 1,3-diamino-2-hydroxypropane is replaced with an equimolar amount of 1,4-diamino-2,3-butanediol to obtain urea-functional monomer 4.

[0045] Preparation Example 2-1

[0046] (S1) Mix 25 parts by mass of isooctyl acrylate, 45 parts by mass of n-butyl acrylate, 3.2 parts by mass of acrylic acid, and 10 parts by mass of methyl methacrylate to obtain a mixed monomer; take 25% of the mixed monomer and add 0.3 wt% of BPO as agent A; take 30% of the mixed monomer and add 0.4 wt% of BPO as agent B; take the remaining mixed monomer and add 10 parts by mass of hydroxyethyl acrylate, 6 parts by mass of urea-functionalized monomer 1 prepared in Preparation Example 1-1, and 0.25 wt% of BPO as agent C;

[0047] (S2) Under a nitrogen atmosphere, agent A was added to 100 parts by mass of ethyl acetate, the temperature was raised to 65°C, and the reaction was maintained for 2 hours; the temperature was raised to 80°C, agent B was added dropwise, and the addition was completed within 1 hour, and the reaction was maintained for 1 hour; agent C was added dropwise, and the addition was completed within 1 hour, and the reaction was maintained for 2 hours.

[0048] (S3) The reaction system was cooled to 40°C, and ethyl acetate was added to adjust the solid content to 40%, resulting in polyurea acrylate prepolymer resin solution 1.

[0049] Preparation Example 2-2

[0050] The other conditions and operations are the same as in Preparation Example 2-1, except that in step (S1), the urea functional monomer 1 is replaced with an equal mass of the urea functional monomer 2 obtained in Preparation Example 1-2, and finally the polyurea acrylate prepolymer resin solution 2 is obtained.

[0051] Preparation Examples 2-3

[0052] The other conditions and operations are the same as in Preparation Example 2-1, except that in step (S1), the urea functional monomer 1 is replaced with an equal mass of the urea functional monomer 3 obtained in Preparation Example 1-3, and finally the polyurea acrylate prepolymer resin solution 3 is obtained.

[0053] Preparation Examples 2-4

[0054] The other conditions and operations are the same as in Preparation Example 2-1, except that in step (S1), the urea functional monomer 1 is replaced with an equal mass of the urea functional monomer 4 obtained in Preparation Example 1-4, and finally the polyurea acrylate prepolymer resin solution 4 is obtained.

[0055] Preparation Examples 2-5

[0056] The other conditions and operations are the same as in Preparation Example 2-1, except that in step (S1), the amount of urea functional monomer 1 is 10 parts by mass, and the final product is polyurea acrylate prepolymer resin solution 5.

[0057] Comparative Preparation Example 1

[0058] The other conditions and procedures are the same as in Preparation Example 2-1, except that in step (S1), no urea functional monomer is added. The final product is a polyacrylate prepolymer resin solution.

[0059] Comparative Preparation Example 2

[0060] The other conditions and operations are the same as in Preparation Example 2-1, except that in step (S1), the urea functional monomer 1 is replaced with 1,3-diallylurea, and the final product is polyurea acrylate prepolymer resin solution 6.

[0061] Example 1

[0062] (1) 250 parts by weight of Preparation Example 2-1 polyurea acrylate prepolymer resin solution 1 (solid content 40%, containing 100 parts by weight of polyurea acrylate prepolymer resin), 1 part by weight of photoinitiator TPO-L (diphenyl-(2,4,6-trimethylbenzoyl)phosphorus oxychloride), 1.5 parts by weight of L-75 curing agent, and 2 parts by weight of plasticizer W-1040-S were stirred and mixed evenly to obtain a urea-based UV-curable polymer composition solution;

[0063] (2) On a coating machine, the urea-based UV-curable polymer composition solution is coated by roller coating at a linear speed of 5 m / min through a total length of 10 m, divided into 4 drying tunnels: Section I at 80℃, Section II at 100℃, Section III at 120℃, and Section IV at 100℃, for further prepolymerization and removal of solvent from the UV-curable pressure-sensitive adhesive; then, the film coated with the UV-curable pressure-sensitive adhesive is laminated with a 110 μm thick PO film (PE material) under a pressure of 0.3 MPa and at room temperature. Finally, it is placed in a 50℃ drying oven for 72 hours to obtain the UV-curable pressure-sensitive tape. The polyester release film substrate thickness is 36 μm, the urea-based UV anti-adhesive layer thickness is 20 μm, and the PO base film thickness is 110 μm. Its properties are shown in Table 1 below.

[0064] Examples 2-5

[0065] The other conditions and operations are the same as in Example 1, except that in step (1), the polyurea acrylate prepolymer resin solution 1 of Preparation Example 2-1 is replaced with the polyurea acrylate prepolymer resin solution 2 to polyurea acrylate prepolymer resin solution 5 obtained in Preparation Examples 2-2 to 2-5.

[0066] Comparative Example 1

[0067] The other conditions and operations are the same as in Preparation Example 2-1, except that in step (1), the polyurea acrylate prepolymer resin solution 1 is replaced with the polyacrylate prepolymer resin solution prepared in Comparative Preparation Example 1.

[0068] Comparative Example 2

[0069] The other conditions and operations are the same as in Preparation Example 2-1, except that in step (1), the polyurea acrylate prepolymer resin solution 1 is replaced with the polyurea acrylate prepolymer resin solution 6 prepared in Comparative Preparation Example 2.

[0070] Example of effect

[0071] The UV pressure-sensitive tapes from Examples 1-5 were cut into 25mm wide strips. The peel strength before and after UV treatment was tested using GB / T 2792-2014 "Test Method for Peel Strength of Adhesive Tapes" (the bonding object was a silicon wafer). (The UV treatment equipment was an LED debonding machine, 365nm wavelength, UV radiation intensity 170mW / cm²). 2 UV radiation energy 300mJ / cm 2 Similarly, after placing the silicone wafers with the adhesive tape in a 150℃ oven for 4 hours, the peel strength after UV treatment was also measured. The peel interface was observed under a microscope to check for residual adhesive and damage to the adhesive / base. The test results are shown in Table 1 below.

[0072] Table 1 Performance Test of Pressure-Sensitive Adhesive Tape

[0073]

[0074] Figure 1 From left to right, the images show the residue at the peeling interface of Examples 1, 2, 1, and 2 after treatment at 150°C for 4 hours followed by UV irradiation. It can be seen that this invention, due to its rational formulation and optimization, can withstand high temperatures and still exhibits excellent UV-induced tack reduction properties after high-temperature treatment, leaving no residue.

[0075] It can be seen that the UV pressure-sensitive tape prepared by the present invention has excellent UV anti-adhesion properties. In particular, it still has good UV anti-adhesion properties after being treated at 150°C. The peel strength is low after UV irradiation and there is no residue. Therefore, the UV-cured pressure-sensitive tape of the present invention is particularly suitable for use in fields such as semiconductor wafer cutting and semiconductor wafer grinding with high-temperature processes.

Claims

1. A urea-containing UV-curable polymer composition, characterized in that, The raw materials include the following parts by weight: 100 parts polyurea acrylate prepolymer resin, 1-2 parts photoinitiator, 1-5 parts curing agent, and 1-5 parts plasticizer; the polyurea acrylate prepolymer resin is obtained by copolymerization of the following monomers in parts by weight: 6-10 parts urea acrylate functional monomer, 60-80 parts soft monomer, 10-20 parts hard monomer, 1-5 parts unsaturated carboxylic acid, and 10-15 parts hydroxyl-containing acrylate monomer; The urea acrylate functional monomer is prepared by a method including the following steps: hydroxy acrylate reacts with isophorone diisocyanate in the presence of a polymerization inhibitor and a catalyst, and then a multifunctional compound is added to continue the reaction to obtain the urea acrylate functional monomer. The hydroxy acrylate monomer is selected from at least one of hydroxyethyl methacrylate and hydroxypropyl methacrylate; The multifunctional compound is at least one selected from 3-amino-1,2-propanediol, 1,3-diamino-2-hydroxypropane, 1,11-diaminoundecane-6-ol, 2,6-diamino-1-hexanol, 2,3-diamino-1-butanol, 2,2-di(aminomethyl)propane-1,3-diol, and 1,4-diamino-2,3-butanediol. The molar ratio of hydroxyacrylate, isophorone diisocyanate and polyfunctional compound is 1:0.9-1:1-1.

1.

2. The urea-containing UV-curable polymer composition according to claim 1, characterized in that, The photoinitiator is at least one of benzoin diethyl ether, ethyl 2,4,6-trimethylbenzoylphenylphosphonate, and phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide; the curing agent is at least one of aziridine curing agents and isocyanates; and the plasticizer is selected from at least one of sebacic acid series, adipic acid series, and phthalic acid series.

3. The urea-containing UV-curable polymer composition according to claim 1, characterized in that, The soft monomer is selected from at least one of isooctyl acrylate, butyl acrylate, and hexyl acrylate; the hard monomer is selected from at least one of vinyl acetate, methyl (meth)propionate, and ethyl (meth)acrylate.

4. The urea-containing UV-curable polymer composition according to claim 1, characterized in that, The reaction of hydroxyacrylate with isophorone diisocyanate is carried out at 0-10℃, with isophorone diisocyanate being slowly added to the system over 1-3 hours. After the addition is complete, the reaction is maintained at this temperature for 3-5 hours. The reaction is continued at 40-50℃ with the addition of a polyfunctional compound, with the polyfunctional compound being slowly added to the system over 1-3 hours. After the addition is complete, the reaction is maintained at this temperature for 3-5 hours.

5. The urea-containing UV-curable polymer composition according to claim 4, characterized in that, The urea acrylate functional monomer is prepared by a method comprising the following steps: 100 parts by mass of hydroxy acrylate is dissolved in 2-4 times its mass of a first organic solvent, a polymerization inhibitor and a catalyst are added, isophorone diisocyanate is added dropwise at a controlled temperature of 0-10°C, the addition is completed in 1-3 hours, and the reaction is maintained at this temperature for 3-5 hours; then, a multifunctional compound is slowly added at a controlled temperature of 40-50°C, the addition is completed in 1-3 hours, the reaction is maintained at this temperature for 3-5 hours, and the solvent and unreacted monomer are removed by vacuum distillation to obtain the urea acrylate functional monomer.

6. The urea-containing UV-curable polymer composition according to claim 1, characterized in that, The polyurea acrylate prepolymer resin is prepared by a method comprising the following steps: (S1) Mix 60-80 parts of soft monomer, 10-20 parts of hard monomer, and 1-5 parts of unsaturated carboxylic acid evenly to form a mixed monomer. Take 25-35 wt% of the mixed monomer and add 0.3-0.35 wt% of the initiator based on the total mass of the monomers to form Agent A. Take 30-40 wt% of the mixed monomer and add 0.4-0.5 wt% of the initiator based on the total mass of the monomers to form Agent B. Add 6-10 parts of urea acrylate functional monomer and 10-15 parts of hydroxyl-containing acrylate monomer to the remaining mixed monomer, and then add 0.2-3 wt% of the initiator based on the total mass of the monomers to form Agent C. The total mass of the monomers is the sum of the masses of the urea acrylate functional monomers, soft monomers, hard monomers, unsaturated carboxylic acids, and hydroxyl-containing acrylate monomers. (S2) Under a protective atmosphere, agent A is added to the second organic solvent, the temperature is raised to 65-70℃, and the reaction is maintained for 1-2 hours; the temperature is raised to 80-85℃, agent B is added dropwise, and the addition is completed within 1-2 hours, and the reaction is maintained for 0.5-1 hours; agent C is added dropwise, and the addition is completed within 1-2 hours, and the reaction is maintained for 1-2 hours. (S3) Cool the reaction system to 40-50℃, add a second organic solvent to adjust the solid content to 30-40%, and obtain a polyurea acrylate prepolymer resin solution.

7. A UV-curable pressure-sensitive tape, comprising, in sequence, a polyester release film, a coating of the urea-based UV-curable polymer composition according to any one of claims 1-6, and a base film.

8. The UV-curable pressure-sensitive tape according to claim 7, characterized in that, The polyester release film is a PET polyester release film; the base film is selected from polyvinyl chloride film, polyethylene film or polypropylene film; the thickness of the polyester release film is 35-45μm, the thickness of the urea-based UV adhesive is 10-20μm, and the thickness of the base film is 80-120μm.

9. The method for preparing the UV-curable pressure-sensitive adhesive tape according to claim 7 or 8, characterized in that, Includes the following steps: A urea-based UV-curable polymer composition solution is uniformly coated onto a polyester release film. After being heated by a temperature gradient, prepolymerization and solvent removal are carried out. Then, the polyester release film coated with urea-based UV-resistant adhesive is laminated with a base film and cured to obtain a UV-curable pressure-sensitive tape.

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