Uv debonding adhesive composition, uv debonding adhesive and wafer dicing using debonding film

Abstract

This invention relates to the field of adhesive technology, specifically to a UV anti-tack adhesive composition, a UV anti-tack adhesive, and an anti-tack film for wafer dicing. By weight, the UV anti-tack adhesive composition comprises: 60-100 parts of an acrylate copolymer base adhesive, 10-30 parts of a gel polymer, 0.05-5 parts of a photoinitiator, 5-20 parts of a first functional monomer, and 30-80 parts of a first solvent. The UV anti-tack adhesive composition of this invention effectively solves the technical contradiction of traditional UV anti-tack adhesives in simultaneously achieving high initial tack and high tack reduction efficiency.

Description

Technical Field

[0001] This invention relates to the field of adhesive technology, and more specifically to a UV anti-tack adhesive composition, a UV anti-tack adhesive, and an anti-tack film for wafer dicing. Background Technology

[0002] Ultraviolet (UV) anti-adhesion adhesives are special pressure-sensitive adhesives that significantly reduce adhesion after being irradiated with ultraviolet light. They are widely used in semiconductor wafer processing, temporary fixation of electronic components, precision device assembly, and medical dressings. An ideal UV anti-adhesion adhesive should possess two key characteristics: first, it should provide sufficiently high initial adhesion during processing to ensure that the adhered objects are firmly fixed and do not shift or fall off; second, it should be able to quickly and thoroughly reduce adhesion after UV irradiation, achieving clean peeling without leaving any residue.

[0003] Currently, most UV-resistant adhesives on the market are based on acrylate polymers, achieving UV-responsive properties by introducing photosensitive groups or photoinitiators. However, this traditional technology has significant limitations: First, to obtain sufficient initial tack, it is often necessary to increase the cohesive strength and crosslinking density of the adhesive, but this makes it difficult to fully disrupt the adhesive network after UV irradiation, resulting in increased residue. Second, single-component acrylate systems cannot simultaneously optimize initial tack and tack reduction effects, presenting a performance balance challenge. Summary of the Invention

[0004] To facilitate a clearer understanding of the technical solutions and effects of this invention, the following detailed description, in conjunction with specific embodiments, is provided. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. In case of conflict, the definitions in this specification shall prevail.

[0005] UV-resistant adhesive composition The first aspect of the present invention provides a UV-resistant adhesive composition, comprising, by weight: 60-100 parts of acrylate copolymer base adhesive, 10-30 parts of gel polymer, 0.05-5 parts of photoinitiator, 5-20 parts of first functional monomer, and 30-80 parts of first solvent.

[0006] In this invention, by controlling the mixing amounts of the components within the aforementioned range, the UV-resistant adhesive obtained from the UV-resistant adhesive composition can exhibit high initial tack and low residue, while also possessing excellent storage stability. This is likely because the acrylate copolymer-based adhesive acts as a continuous phase, providing high initial tack through the strong adhesion of its molecular chains; while the dispersed gel polymer, as a smart responsive phase, undergoes rapid phase transition shrinkage upon UV irradiation, generating microscopic stress concentration at the phase interface. Simultaneously, the free radical reaction excited by the photoinitiator promotes the deconstruction of the polymer network. The synergistic effect of these two factors leads to a sharp decrease in the cohesive energy within the adhesive, thereby achieving reduced adhesion without producing residue.

[0007] As a preferred technical solution of the present invention, the UV anti-tack adhesive composition comprises, by weight: 80-90 parts of acrylate copolymer base adhesive, 10-15 parts of gel polymer, 0.3-0.5 parts of photoinitiator, 8-12 parts of functional monomer, and 40-50 parts of solvent.

[0008] As a preferred technical solution of the present invention, the preparation method of the acrylate copolymer-based adhesive includes: in the presence of an initiator and a second solvent, a soft monomer, a hard monomer, and a second functional monomer undergo a polymerization reaction to obtain an acrylate copolymer-based adhesive.

[0009] As a preferred embodiment of the present invention, the soft monomer is selected from at least one of ethyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate and hydroxyethyl acrylate, preferably 2-ethylhexyl acrylate.

[0010] As a preferred embodiment of the present invention, the hard monomer is selected from at least one of isoborneol acrylate, acrylamide, vinyl acetate, and methyl methacrylate, preferably isoborneol acrylate and / or methyl methacrylate, more preferably isoborneol acrylate and methyl methacrylate, and even more preferably isoborneol acrylate and methyl methacrylate in a mass ratio of 1:(1.5-4), for example 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, or 1:4.

[0011] As a preferred embodiment of the present invention, the second functional monomer is selected from at least one of 3-acrylamidodopamine, hydroxypropyl methacrylate, hydroxypropyl acrylate, and 4-methacryloyloxybenzophenone; preferably 3-acrylamidodopamine and 4-methacryloyloxybenzophenone; more preferably, the mass ratio of 3-acrylamidodopamine to 4-methacryloyloxybenzophenone is 1:(0.5-0.8), for example, 1:0.5, 1:0.6, 1:0.7, 1:0.8, etc.

[0012] The study found that by controlling the specific types of soft monomers, hard monomers, and second functional monomers in the preparation of acrylate copolymer-based adhesives, the UV-reducing adhesives obtained from the UV-reducing adhesive composition can better exhibit high initial tack and low residual adhesive rate. This is presumably because the synergistic effect of soft and hard monomers significantly improves peel resistance while maintaining tack. Furthermore, by combining 3-acrylamidodopamine and 4-methacryloyloxybenzophenone, 3-acrylamidodopamine can introduce catechol groups, which can greatly enhance interfacial adhesion through multiple bonding. The benzophenone structure in 4-methacryloyloxybenzophenone can not only act as a photoinitiating site to promote UV crosslinking / degradation, but also further generate a synergistic photosensitizing effect with catechol, promoting a rapid decrease in adhesion during the subsequent UV tack reduction stage.

[0013] As a preferred embodiment of the present invention, the initiator is selected from azobisisobutyronitrile and / or benzoyl peroxide, preferably azobisisobutyronitrile.

[0014] In a preferred embodiment of the present invention, the second solvent is ethyl acetate.

[0015] As a preferred technical solution of the present invention, the mass ratio of the soft monomer, the hard monomer and the second functional monomer is 1:(0.5-2):(0.05-0.5), preferably 1:(1-1.2):(0.2-0.25).

[0016] In this invention, by controlling the mass ratio of soft monomer, hard monomer and second functional monomer within the above range, the effects of high initial tack and efficient photo-triggered tack reduction can be better balanced, thereby achieving a better balance between high initial tack and low residual tack.

[0017] As a preferred embodiment of the present invention, the mass of the initiator is 0.3%-1% of the total mass of the soft monomer, hard monomer, and second functional monomer.

[0018] As a preferred embodiment of the present invention, the amount of the second solvent is 40%-50% of the total mass of the soft monomer, hard monomer and second functional monomer.

[0019] As a preferred technical solution of the present invention, the polymerization reaction conditions include: being carried out under a nitrogen atmosphere, at a temperature of 65-70°C, with a reaction endpoint of 25°C and a viscosity of 400,000-500,000 cps.

[0020] Specifically, the preparation method of the acrylate copolymer-based adhesive includes: Azobisisobutyronitrile (AIBN) and ethyl acetate were mixed evenly to obtain a mixture. Then, under a nitrogen atmosphere at 65-70°C, the mixture was added dropwise to a mixture of soft monomers, hard monomers, and a second functional monomer. The reaction was stopped when the viscosity of the reaction system at 25°C reached 400,000-500,000 cps, and the resulting acrylate copolymer-based adhesive was obtained.

[0021] As a preferred embodiment of the present invention, the method for preparing the gel polymer includes: (1) Dissolve polyvinyl alcohol in water to prepare a polyvinyl alcohol aqueous solution with a mass concentration of 10%-15%; (2) Add a 15%-30% sodium hydroxide aqueous solution to the acrylic acid to neutralize it to a pH of 6-6.5 to obtain a neutralized acrylic acid solution; (3) Add N-isopropylacrylamide, N,N'-methylenebisacrylamide and 10%-15% ammonium persulfate aqueous solution to the neutralized acrylic acid solution in sequence to carry out polymerization reaction. Then, purify, dry and pulverize by swelling and shrinkage method to obtain gel polymer.

[0022] In this invention, the synergistic effect of the gel polymer and the acrylate copolymer-based adhesive enables the UV-resistant adhesive obtained from the UV-resistant adhesive composition to have high initial tack and low residual rate. However, it was found in the research that the amount of gel polymer added must be strictly controlled. When the amount added is too much, it will lead to poor initial tack and poor storage stability. It is speculated that this is because excessive gel polymer will destroy the continuous phase of the acrylate-based adhesive, forming an unstable structure dominated by a fragile gel phase, resulting in insufficient overall cohesive strength of the colloid, thus resulting in poor initial tack. In addition, a large number of gel particles are very prone to aggregation, sedimentation or solvent adsorption during storage, leading to phase separation and viscosity changes in the system, making it impossible to store stably.

[0023] As a preferred embodiment of the present invention, the polyvinyl alcohol is polyvinyl alcohol 1788 type.

[0024] As a preferred technical solution of the present invention, the mass ratio of polyvinyl alcohol, acrylic acid, N-isopropylacrylamide, N,N'-methylenebisacrylamide to ammonium persulfate in the aqueous solution is 1:(2-2.5):(5-6):(0.3-0.5):(0.03-0.05).

[0025] There are no special limitations on the method of dissolving polyvinyl alcohol in water in step (1) above. For example, it can be dissolved at a temperature of 80-90°C. This invention does not impose any special limitations on this method, and this invention will not elaborate on it.

[0026] As a preferred technical solution of the present invention, in step (2), the neutralization is carried out at 0-5℃.

[0027] As a preferred technical solution of the present invention, in step (3), the conditions of the polymerization reaction include: being carried out under nitrogen protection, at a temperature of 50-55°C, and for a time of 6-8 hours.

[0028] The above swelling and shrinkage purification method is used to remove unreacted monomers and other impurities. Specifically, the material obtained from the polymerization reaction is left to stand for 2-3 hours, then cut into small pieces and soaked in a large amount of water. It is swollen at room temperature for 8-12 hours, and then shrunk in water at 60-70℃ for 1-2 hours. The wastewater is then discarded, and the process is repeated 2-3 times.

[0029] The above-mentioned pulverization is generally carried out to an average particle size of 100-200 micrometers. The above-mentioned drying and pulverization are conventional operation methods in the field, and the present invention will not elaborate on them further.

[0030] Specifically, the preparation method of the gel polymer includes: (1) At 80-90℃, dissolve polyvinyl alcohol in water to prepare a polyvinyl alcohol aqueous solution with a mass concentration of 10%-15%; (2) At 0-5℃, add a 15%-30% sodium hydroxide aqueous solution to the acrylic acid to neutralize it to a pH of 6-6.5 to obtain a neutralized acrylic acid solution; (3) Under nitrogen protection, N-isopropylacrylamide, N,N'-methylenebisacrylamide, and 10%-15% ammonium persulfate aqueous solution were added sequentially to the neutralized acrylic acid solution in polyvinyl alcohol aqueous solution. The reaction was carried out at 50-55℃ for 6-8 hours. After that, the material obtained from the polymerization reaction was allowed to stand for 2-3 hours, then cut into small pieces and soaked in a large amount of water. It was swollen at room temperature for 8-12 hours, then shrank in water at 60-70℃ for 1-2 hours. The wastewater was discarded, and the process was repeated 2-3 times. The mixture was dried and pulverized to 100-200 micrometers to obtain the gel polymer.

[0031] The mass ratio of polyvinyl alcohol, acrylic acid, N-isopropylacrylamide, N,N'-methylenebisacrylamide to ammonium persulfate in the aqueous solution is 1:(2-2.5):(5-6):(0.3-0.5):(0.03-0.05).

[0032] As a preferred technical solution of the present invention, the functional monomer is selected from at least one of glycidyl methacrylate, difunctional polyurethane acrylate and caprolactone acrylate, preferably difunctional polyurethane acrylate.

[0033] In a specific embodiment of this invention, research has found that using difunctional polyurethane acrylate can better achieve the effects of high initial tack and low residual adhesive. It is speculated that this is because difunctional polyurethane acrylate can form an interpenetrating network structure with the base adhesive. Before UV irradiation, its own rigid urethane bonds can enhance the cohesive strength of the adhesive, thereby improving the initial tack. During UV irradiation, the urethane bonds in the difunctional polyurethane acrylate molecular chain can be preferentially broken as "sacrificial bonds", synergistically promoting the rapid collapse of the cohesive energy in the adhesive, thereby achieving a thorough and low residual peeling effect after UV irradiation while maintaining high initial tack.

[0034] The difunctional polyurethane acrylate used in this invention can be obtained commercially, for example, Inoue UV-8901 difunctional polyurethane acrylate.

[0035] As a preferred embodiment of the present invention, the first solvent is selected from at least one of ethyl acetate, methanol, ethanol, isopropanol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, and propylene glycol monomethyl ether acetate.

[0036] As a preferred embodiment of the present invention, the first solvent is ethyl acetate, isopropanol and propylene glycol monomethyl ether acetate in a weight ratio of (5-6):(2-3):1.

[0037] In the system characteristic of this invention, it has been found that using a specific ratio of ethyl acetate, isopropanol, and propylene glycol monomethyl ether acetate as solvents results in a composition with superior storage stability, high initial tack, and low residual adhesive content. This is presumably because ethyl acetate, in this embodiment of the invention, allows the molecular chains of the acrylate-based adhesive to fully extend; isopropanol promotes uniform swelling and dispersion of the gel polymer; and propylene glycol monomethyl ether acetate, with its high boiling point, not only regulates the overall evaporation gradient to prevent coating defects but also enhances the compatibility of the components through its unique molecular structure, resulting in a superior microstructure after the UV-resistant adhesive film is formed.

[0038] As a preferred embodiment of the present invention, the photoinitiator is selected from at least one of α-hydroxyisobutyrophenone, 2-methyl-1-(4-methylthiophenyl)-2-morpholino-1-propanone, benzophenone-1-hydroxycyclohexylphenyl ketone, and 2,4-diethylthioxanthrone.

[0039] UV adhesive A second aspect of the present invention provides a UV anti-tack adhesive, which is prepared by mixing the components of a UV anti-tack adhesive composition, wherein the UV anti-tack adhesive composition is the UV anti-tack adhesive composition described in the first aspect of the present invention.

[0040] As a preferred embodiment of the present invention, the preparation method of the UV-resistant adhesive includes: S1. Swell and disperse a portion of the solvent with the gel polymer to obtain a gel polymer solution with a concentration of 50%-60% by weight. S2. Mix and degas the acrylate copolymer base adhesive, gel polymer solution, photoinitiator, functional monomer and remaining solvent to obtain UV anti-stick adhesive.

[0041] As a preferred technical solution of the present invention, in step S1, the swelling conditions include: swelling at room temperature for 24-36 hours.

[0042] As a preferred technical solution of the present invention, in step S1, the dispersion conditions include: ultrasonication for 30-60 minutes under a power of 300-500W.

[0043] As a preferred technical solution of the present invention, in step S2, the mixing conditions include: stirring at room temperature for 2-4 hours.

[0044] As a preferred technical solution of the present invention, in step S2, the degassing conditions include: degassing for 20-50 minutes under -0.1MPa conditions.

[0045] Anti-adhesion film for wafer dicing A third aspect of the present invention provides an anti-adhesion film for wafer dicing, comprising a substrate, a UV anti-adhesion adhesive, and a release film stacked sequentially; wherein the UV anti-adhesion adhesive is the UV anti-adhesion adhesive described in the second aspect of the present invention.

[0046] There are no special restrictions on the substrate material in this invention. Materials well known to those skilled in the art can be selected, including but not limited to substrates made of the following materials: polyethylene, polypropylene, polybutene, polyurethane, etc.

[0047] There are no special restrictions on the release film in this invention. Materials well known to those skilled in the art can be selected, including but not limited to films made of the following materials: polyethylene, polypropylene, polybutadiene, polytetrafluoroethylene, etc.

[0048] Compared with the prior art, the present invention has at least the following beneficial effects: The UV tack-reducing adhesive composition of the present invention effectively solves the technical contradiction that traditional UV tack-reducing adhesives cannot simultaneously achieve both initial tack and tack-reducing efficiency. Detailed Implementation

[0049] The present invention will now be described in detail through embodiments: In the following embodiments, The polyvinyl alcohol is designated as polyvinyl alcohol 1788.

[0050] The model number of the difunctional polyurethane acrylate is Inoue UV-8901 difunctional polyurethane acrylate.

[0051] Example 1 Preparation of acrylate copolymer-based adhesives: Azobisisobutyronitrile (AIBN) and ethyl acetate were mixed uniformly to obtain a mixture. Then, under a nitrogen atmosphere at 58°C, the mixture was dropwise added to a mixture of 2-ethylhexyl acrylate, isobornyl acrylate, methyl methacrylate, 3-acrylamidodopamine, and 4-methacryloyloxybenzophenone in a mass ratio of 1:0.3:0.7:0.15:0.08. The reaction was stopped when the viscosity of the reaction system at 25°C reached 420,000 cps, yielding an acrylate copolymer-based adhesive. The mass of AIBN was 0.35% of the total mass of 2-ethylhexyl acrylate, isobornyl acrylate, methyl methacrylate, 3-acrylamidodopamine, and 4-methacryloyloxybenzophenone, and the mass of ethyl acetate was 48% of the total mass of 2-ethylhexyl acrylate, isobornyl acrylate, methyl methacrylate, 3-acrylamidodopamine, and 4-methacryloyloxybenzophenone.

[0052] Preparation of gel polymers: (1) At 85°C, polyvinyl alcohol is dissolved in water to prepare a polyvinyl alcohol aqueous solution with a mass concentration of 12%; (2) At 5°C, add a 20% sodium hydroxide aqueous solution to the acrylic acid to neutralize it until the pH value is 6.3, and obtain a neutralized acrylic acid solution; (3) Under nitrogen protection, N-isopropylacrylamide, N,N'-methylenebisacrylamide and 12% ammonium persulfate aqueous solution were added to the neutralized acrylic acid solution in sequence and reacted at 55°C for 6 hours. After that, the material obtained by polymerization was left to stand for 2 hours, cut into small pieces and soaked in a large amount of water. It was swollen at room temperature for 10 hours, and then shrank in water at 65°C for 2 hours. The wastewater was discarded, and the process was repeated twice. The mixture was dried and pulverized to 100 micrometers to obtain a gel polymer. The mass ratio of polyvinyl alcohol, acrylic acid, N-isopropylacrylamide, N,N'-methylenebisacrylamide to ammonium persulfate in the aqueous solution is 1:2.2:5.6:0.4:0.04.

[0053] Preparation of UV-resistant adhesives: S1. Prepare 88 parts by weight of acrylate copolymer base glue, 12 parts of gel polymer, 0.4 parts of α-hydroxyisobutyroxene, 10 parts of difunctional polyurethane acrylate, 28 parts of ethyl acetate, 12 parts of isopropanol, and 5 parts of propylene glycol monomethyl ether acetate; and mix ethyl acetate, isopropanol, and propylene glycol monomethyl ether acetate evenly as a mixing solvent. S2. Mix a portion of the mixed solvent with the gel polymer and let it swell at room temperature for 24 hours. Then, disperse it by sonication for 30 minutes at a power of 500W to obtain a gel polymer solution with a concentration of 55% by weight. S3. The acrylate copolymer base adhesive, gel polymer solution, α-hydroxyisobutyroxene, difunctional polyurethane acrylate and the remaining mixed solvent are stirred at room temperature for 3 hours, and then degassed at -0.1MPa for 30 minutes to obtain UV anti-tack adhesive.

[0054] Example 2 Preparation of acrylate copolymer-based adhesives: Azobisisobutyronitrile (AIBN) and ethyl acetate were mixed uniformly to obtain a mixture. Then, under a nitrogen atmosphere at 58°C, the mixture was dropwise added to a mixture of 2-ethylhexyl acrylate, isobornyl acrylate, methyl methacrylate, 3-acrylamidodopamine, and 4-methacryloyloxybenzophenone in a mass ratio of 1:0.4:0.8:0.15:0.1. The reaction was stopped when the viscosity of the reaction system reached 450,000 cps at 25°C, yielding an acrylate copolymer-based adhesive. The mass of AIBN was 0.35% of the total mass of 2-ethylhexyl acrylate, isobornyl acrylate, methyl methacrylate, 3-acrylamidodopamine, and 4-methacryloyloxybenzophenone, and the mass of ethyl acetate was 45% of the total mass of 2-ethylhexyl acrylate, isobornyl acrylate, methyl methacrylate, 3-acrylamidodopamine, and 4-methacryloyloxybenzophenone.

[0055] Preparation of gel polymers: (1) At 90°C, polyvinyl alcohol is dissolved in water to prepare a polyvinyl alcohol aqueous solution with a mass concentration of 15%; (2) At 5°C, add a 20% sodium hydroxide aqueous solution to the acrylic acid to neutralize it until the pH value is 6.5, and obtain a neutralized acrylic acid solution; (3) Under nitrogen protection, N-isopropylacrylamide, N,N'-methylenebisacrylamide and 15% ammonium persulfate aqueous solution were added to the neutralized acrylic acid solution in sequence and reacted at 50°C for 8 hours. After that, the material obtained by polymerization was left to stand for 2 hours, then cut into small pieces and soaked in a large amount of water. It was swollen at room temperature for 10 hours, then shrank in water at 65°C for 2 hours. The wastewater was discarded, and the process was repeated twice. The mixture was dried and pulverized to 100 micrometers to obtain a gel polymer. The mass ratio of polyvinyl alcohol, acrylic acid, N-isopropylacrylamide, N,N'-methylenebisacrylamide to ammonium persulfate in the aqueous solution is 1:2.5:6:0.5:0.03.

[0056] Preparation of UV-resistant adhesives: S1. Prepare 80 parts by weight of acrylate copolymer base glue, 15 parts of gel polymer, 0.3 parts of α-hydroxyisobutyroxene, 8 parts of difunctional polyurethane acrylate, 27 parts of ethyl acetate, 17 parts of isopropanol, and 6 parts of propylene glycol monomethyl ether acetate; and mix ethyl acetate, isopropanol, and propylene glycol monomethyl ether acetate evenly as a mixing solvent. S2. Mix a portion of the mixed solvent with the gel polymer and let it swell at room temperature for 30 hours. Then, disperse it by sonication for 50 minutes at a power of 400W to obtain a gel polymer solution with a concentration of 50% by weight. S3. The acrylate copolymer base adhesive, gel polymer solution, α-hydroxyisobutyroxene, difunctional polyurethane acrylate and the remaining mixed solvent are stirred at room temperature for 3 hours, and then degassed at -0.1MPa for 30 minutes to obtain UV anti-tack adhesive.

[0057] Example 3 The method according to Example 1 differs in that: In the preparation of acrylate copolymer-based adhesives: Azobisisobutyronitrile (AIBN) and ethyl acetate were mixed uniformly to obtain a mixture. Then, under a nitrogen atmosphere at 58°C, the mixture was dropwise added to a mixture of 2-ethylhexyl acrylate, isobornyl acrylate, methyl methacrylate, and 4-methacryloyloxybenzophenone in a mass ratio of 1:0.3:0.7:0.23. The reaction was stopped when the viscosity of the reaction system at 25°C reached 420,000 cps, yielding an acrylate copolymer-based adhesive. The mass of AIBN was 0.35% of the total mass of 2-ethylhexyl acrylate, isobornyl acrylate, methyl methacrylate, and 4-methacryloyloxybenzophenone, and the mass of ethyl acetate was 48% of the total mass of 2-ethylhexyl acrylate, isobornyl acrylate, methyl methacrylate, and 4-methacryloyloxybenzophenone.

[0058] Finally, acrylate copolymer-based adhesive and the corresponding UV-resistant adhesive were prepared.

[0059] Example 4 The method according to Example 1 differs in that: In the preparation of acrylate copolymer-based adhesives: The mass ratio of 2-ethylhexyl acrylate, isobornyl acrylate, methyl methacrylate, 3-acrylamidodopamine, and 4-methacryloyloxybenzophenone is 1:0.3:0.7:0.45:0.24.

[0060] Finally, acrylate copolymer-based adhesive and the corresponding UV-resistant adhesive were prepared.

[0061] Example 5 The method according to Example 1 differs in that: In the preparation of UV-resistant adhesives: Prepare 88 parts by weight of acrylate copolymer base glue, 12 parts of gel polymer, 0.4 parts of α-hydroxyisobutyroxene, 10 parts of difunctional polyurethane acrylate, 17 parts of ethyl acetate, 20 parts of isopropanol, and 8 parts of propylene glycol monomethyl ether acetate; and mix ethyl acetate, isopropanol, and propylene glycol monomethyl ether acetate evenly as a mixing solvent.

[0062] The UV-resistant adhesive was finally prepared.

[0063] Example 6 The method according to Example 1 differs in that: In the preparation of UV-resistant adhesives: Prepare 88 parts by weight of acrylate copolymer base glue, 12 parts of gel polymer, 0.4 parts of α-hydroxyisobutyroxene, 10 parts of difunctional polyurethane acrylate, 3 parts of ethyl acetate, 2 parts of isopropanol, and 40 parts of propylene glycol monomethyl ether acetate; and mix ethyl acetate, isopropanol, and propylene glycol monomethyl ether acetate evenly as a mixing solvent.

[0064] The UV-resistant adhesive was finally prepared.

[0065] Example 7 The method according to Example 1 differs in that: In the preparation of UV-resistant adhesives: Replace the difunctional polyurethane acrylate with caprolactone acrylate.

[0066] The UV-resistant adhesive was finally prepared.

[0067] Comparative Example 1 Preparation of UV-resistant adhesives: S1. Prepare 98 parts by weight of acrylate copolymer base adhesive (same as in Example 1), 0.4 parts of α-hydroxyisobutyroxene, 12 parts of difunctional polyurethane acrylate, 19 parts of ethyl acetate, 8 parts of isopropanol, and 4 parts of propylene glycol monomethyl ether acetate; and mix ethyl acetate, isopropanol, and propylene glycol monomethyl ether acetate evenly as a mixing solvent. S2. The acrylate copolymer base adhesive, α-hydroxyisobutyroxene, difunctional polyurethane acrylate and mixed solvent are stirred at room temperature for 3 hours, and then degassed at -0.1MPa for 30 minutes to obtain UV anti-tack adhesive.

[0068] Comparative Example 2 The method according to Example 1 differs in that: In the preparation of UV-resistant adhesives: Prepare 88 parts by weight of acrylate copolymer base glue, 35 parts of gel polymer, 0.4 parts of α-hydroxyisobutyroxene, 10 parts of difunctional polyurethane acrylate, 54 parts of ethyl acetate, 36 parts of isopropanol, and 15 parts of propylene glycol monomethyl ether acetate; and mix ethyl acetate, isopropanol, and propylene glycol monomethyl ether acetate evenly as a mixing solvent.

[0069] The UV-resistant adhesive was finally prepared.

[0070] Performance testing The UV anti-tack adhesives in the examples and comparative examples were used to prepare wafer dicing anti-tack films according to the following schemes.

[0071] Preparation of anti-adhesion film for wafer dicing: UV anti-adhesion adhesive was coated onto a 50-micron thick polyethylene substrate using a coating machine. After coating, the substrate was placed in a 100℃ oven and baked for 2 minutes. After drying, the film thickness was approximately 22±2 μm. Then, a release film was attached using a flatbed laminator. The release surface of a PET light release film was attached to the dried UV anti-adhesion adhesive. The substrate was cured at 60℃ for 48 hours to obtain the anti-adhesion film for wafer dicing.

[0072] 1. According to GB / T2792-2014, the 180° peel strength of the anti-adhesion film for wafer dicing was tested. After drying and curing in an oven at 80℃ for 2 hours, the release film of the UV anti-adhesion film was removed and adhered to a mirror stainless steel plate. Then, it was rolled back and forth three times with a 1kg rubber roller and left to stand in the dark for 15 minutes. The 180° peel strength of the UV anti-adhesion film before and after UV irradiation was tested using a 180° peel tester. The test object was then peeled from the steel plate at a peel speed of 300mm / min and a peel angle of 180°. The peel force of the test object before UV irradiation was recorded. The test speed was 300mm / min, and the test temperature was 25℃. UV irradiation conditions: 365nm wavelength, intensity 120-150mW / cm², energy 5J / cm². 2 Nitrogen protection, followed by standing for 20 minutes after irradiation.

[0073] 2. Storage stability test: According to GB / T 2792-1995 standard, the viscosity of UV anti-tack adhesive was measured at room temperature using an NDJ-8S rotational viscometer. After that, the UV anti-tack adhesive was left at room temperature for 3 days, and its viscosity was tested and the viscosity change rate was calculated.

[0074] The test results are shown in Table 1.

[0075] Table 1 Performance Test Results

[0076] The test results above show that the UV tack-reducing adhesive composition of the present invention effectively solves the technical contradiction that traditional UV tack-reducing adhesives cannot simultaneously achieve both initial tack and tack-reducing efficiency.

Claims

1. A UV-resistant adhesive composition, characterized in that, By weight, it comprises: 60-100 parts of acrylate copolymer base adhesive, 10-30 parts of gel polymer, 0.05-5 parts of photoinitiator, 5-20 parts of first functional monomer, and 30-80 parts of first solvent.

2. The UV-resistant adhesive composition according to claim 1, characterized in that, The preparation method of the acrylate copolymer-based adhesive includes: in the presence of an initiator and a second solvent, a soft monomer, a hard monomer, and a second functional monomer undergo a polymerization reaction to obtain the acrylate copolymer-based adhesive.

3. The UV-resistant adhesive composition according to claim 2, characterized in that, The soft monomer is selected from at least one of ethyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, and hydroxyethyl acrylate; the hard monomer is selected from at least one of isobornyl acrylate, acrylamide, vinyl acetate, and methyl methacrylate; the second functional monomer is selected from at least one of 3-acrylamidodopamine, hydroxypropyl methacrylate, hydroxypropyl acrylate, and 4-methacryloyloxybenzophenone.

4. The UV-resistant adhesive composition according to claim 2, characterized in that, The initiator is selected from azobisisobutyronitrile and / or benzoyl peroxide; the second solvent is ethyl acetate; the mass ratio of the soft monomer, hard monomer and second functional monomer is 1:(0.5-2):(0.05-0.5); the mass of the initiator is 0.3%-1% of the total mass of the soft monomer, hard monomer and second functional monomer; the amount of the second solvent is 40%-50% of the total mass of the soft monomer, hard monomer and second functional monomer; the polymerization reaction conditions include: carried out under a nitrogen atmosphere, at a temperature of 65-70℃, with a reaction endpoint of 25℃ and a viscosity of 400,000-500,000 cps.

5. The UV-resistant adhesive composition according to claim 2, characterized in that, The preparation method of the gel polymer includes: (1) Dissolve polyvinyl alcohol in water to prepare a polyvinyl alcohol aqueous solution with a mass concentration of 10%-15%; (2) Add a 15%-30% sodium hydroxide aqueous solution to the acrylic acid to neutralize it to a pH of 6-6.5 to obtain a neutralized acrylic acid solution; (3) Add N-isopropylacrylamide, N,N'-methylenebisacrylamide and 10%-15% ammonium persulfate aqueous solution to the neutralized acrylic acid solution in sequence to carry out polymerization reaction. Then, purify, dry and pulverize by swelling and shrinkage method to obtain gel polymer.

6. The UV-resistant adhesive composition according to claim 5, characterized in that, The mass ratio of polyvinyl alcohol, acrylic acid, N-isopropylacrylamide, N,N'-methylenebisacrylamide to ammonium persulfate in the aqueous solution is 1:(2-2.5):(5-6):(0.3-0.5):(0.03-0.05).

7. The UV-resistant adhesive composition according to claim 5, characterized in that, In step (2), the neutralization is carried out at 0-5℃; in step (3), the conditions for the polymerization reaction include: under nitrogen protection, at a temperature of 50-55℃, for a time of 6-8 hours.

8. The UV-resistant adhesive composition according to claim 1, characterized in that, The functional monomer is selected from at least one of glycidyl methacrylate, difunctional polyurethane acrylate, and caprolactone acrylate; the first solvent is selected from at least one of ethyl acetate, methanol, ethanol, isopropanol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, and propylene glycol monomethyl ether acetate; the photoinitiator is selected from at least one of α-hydroxyisobutyrophenyl, 2-methyl-1-(4-methylthiophenyl)-2-morpholine-1-propanone, benzophenone-1-hydroxycyclohexylphenyl ketone, and 2,4-diethylthioxanthrone.

9. A UV-resistant adhesive, characterized in that, It is prepared by mixing the components of a UV anti-tack composition, wherein the UV anti-tack composition is the UV anti-tack composition according to any one of claims 1-8.

10. An anti-adhesion film for wafer dicing, characterized in that, It includes a substrate, a UV anti-tack adhesive, and a release film stacked in sequence; wherein the UV anti-tack adhesive is the UV anti-tack adhesive as described in claim 9.

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