A pressure-sensitive adhesive composition, a pressure-sensitive adhesive, a preparation method thereof, and a pressure-sensitive adhesive article

Abstract

The present invention relates to the technical field of pressure-sensitive adhesives, and particularly relates to a pressure-sensitive adhesive composition, a pressure-sensitive adhesive, a preparation method thereof, and a pressure-sensitive adhesive product. The pressure-sensitive adhesive composition of the present invention comprises the following raw materials: a soft monomer, optionally a hard monomer, a functional monomer, a photoinitiator, and a chain transfer agent; the functional monomer comprises a first functional monomer and a second functional monomer, and the first functional monomer and the second functional monomer are different. Different functional monomers are used in the composition of the present invention, which improves the crosslinking density of the colloid, and enables the pressure-sensitive adhesive containing the composition to have good high-temperature resistance, pressure sensitivity, and coating viscosity; the pressure-sensitive adhesive prepared by the preparation method of the present invention has good high-temperature resistance performance. After the tape is baked at 200 °C for 1 h when attached to the chip, the tape does not turn yellow or have bubbles, and there is no residual glue after the tape is peeled off, and it has good pressure sensitivity.

Description

Technical Field

[0001] The present invention relates to the technical field of pressure - sensitive adhesives, and particularly relates to a pressure - sensitive adhesive composition, a pressure - sensitive adhesive, a preparation method thereof, and a pressure - sensitive adhesive product. Background Art

[0002] A pressure - sensitive adhesive is a pressure - sensitive adhesive, also known as self - adhesive, which has advantages such as good temperature resistance, a wide range of peel strengths, strong cohesion, good chemical and aging resistance, and a wide range of applications. Therefore, it is often used in the industrial and electronic industries. With technological progress, some pressure - sensitive adhesives have better performance and can be applied to the aerospace and semiconductor industries.

[0003] The main synthesis methods of acrylic pressure - sensitive adhesives are: solvent method, emulsion method, and radiation curing method. Currently, the solvent method is mostly used in the industry, which has advantages such as a wide range of applications and simple reaction control. However, a large amount of organic solvents will be used in the specific operation process of the solvent method, and the solvents volatilized during the operation process will cause damage to the environment and operators. The emulsion method uses water as the reaction medium to avoid the emission of organic solvents. However, the emulsion method in the prior art has problems such as single product performance and high energy consumption during the drying process. The radiation curing method is mainly UV curing, with 100% reaction solid content, avoiding the use of solvents, and low energy consumption of the light source, which is the direction of the green and environmental protection development of pressure - sensitive adhesives.

[0004] With the development of the electronic industry, the semiconductor industry pursues miniaturization, high integration, high electron density, high efficiency and high yield. Therefore, the surface - mount technology (SMT) has become the most popular technology and process in the electronic assembly industry. The SMT process flow includes steps such as material preparation and loading, solder paste printing, solder paste inspection, component placement, reflow soldering, inspection, and repair.

[0005] Therefore, it is very important to study a high - temperature - resistant pressure - sensitive adhesive that can fix and protect chips during the reflow soldering stage. Summary of the Invention

[0006] In view of this, the present invention provides a pressure - sensitive adhesive composition, a pressure - sensitive adhesive, a preparation method thereof, and a pressure - sensitive adhesive product. Different functional monomers are used in the composition of the present invention, which improves the cross - linking density of the colloid, making the pressure - sensitive adhesive containing this composition have good high - temperature resistance, pressure - sensitivity, and coating viscosity. The pressure - sensitive adhesive prepared by the preparation method of the present invention has good high - temperature resistance. After the tape is baked at 200 °C for 1 h while being attached to the chip, the tape does not turn yellow, does not have bubbles, and does not leave residual glue after the tape is peeled off, and has good pressure - sensitivity.

[0007] The first aspect of the present invention provides a pressure - sensitive adhesive composition, comprising the following raw materials: soft monomers, optionally hard monomers, functional monomers, photoinitiators, and chain transfer agents;

[0008] The functional monomers include a first functional monomer and a second functional monomer, and the first functional monomer is different from the second functional monomer.

[0009] In one example, the mass ratio of the first functional monomer to the second functional monomer is 1:(0.1 - 10), preferably 1:(0.2 - 5).

[0010] In one example, the first functional monomer and the second functional monomer are each independently selected from one or more of monofunctional or polyfunctional acrylates, monofunctional or polyfunctional polyurethane acrylates, monofunctional N-vinylpyrrolidone, monofunctional glycidyl (meth)acrylate, bifunctional N-methylolacrylamide, bifunctional polyethylene glycol dimethacrylate, bifunctional divinylbenzene, and bifunctional 1,6-hexanediol diacrylate.

[0011] In one example, the mass ratio of the soft monomer, the hard monomer, and the functional monomer is 1:(0 - 0.14):(0.01 - 0.14).

[0012] In one example, the soft monomer is one or more of butyl acrylate, isooctyl acrylate, ethyl acrylate, n-octyl acrylate, 2-hydroxyethyl acrylate, lauryl acrylate, and lauryl methacrylate.

[0013] In one example, the hard monomer is one or more of methyl methacrylate, styrene, acrylic acid, vinyl acetate, ethyl methacrylate, isobutyl methacrylate, acrylonitrile, cyclohexyl methacrylate, and isobornyl methacrylate.

[0014] In one example, the photoinitiator includes a first photoinitiator, a second photoinitiator, and a third photoinitiator; the second photoinitiator is the same as the first photoinitiator, and the third photoinitiator is different from the first photoinitiator.

[0015] In one example, the pressure-sensitive adhesive composition further includes a silane coupling agent and an antistatic agent.

[0016] The second aspect of the present invention provides a pressure-sensitive adhesive, which includes the pressure-sensitive adhesive composition described in the first aspect of the present invention, or is prepared from the pressure-sensitive adhesive composition.

[0017] The third aspect of the present invention provides a method for preparing the pressure-sensitive adhesive described in the second aspect of the present invention, including the following steps:

[0018] (1) In the presence of a first light source and an inert gas, mix the soft monomer, optionally the hard monomer, the first photoinitiator, and a chain transfer agent to obtain a prepolymer;

[0019] (2) Under a light-shielded environment, add the first functional monomer, the second functional monomer, the second photoinitiator, the third photoinitiator, the silane coupling agent, and the antistatic agent to the prepolymer obtained in step (1) and mix evenly.

[0020] The fourth aspect of the present invention provides a pressure-sensitive adhesive product, including at least one of the pressure-sensitive adhesive composition described in the first aspect of the present invention, the pressure-sensitive adhesive described in the second aspect of the present invention, and the pressure-sensitive adhesive prepared by the method described in the third aspect of the present invention.

[0021] Compared with the prior art, the present invention has the following technical advantages:

[0022] (1) By adding at least two different functional monomers, the pressure-sensitive adhesive of the present invention introduces multiple reaction sites to form a network structure, improves the crosslinking density of the colloid, enhances the high-temperature resistance of the pressure-sensitive adhesive, and balances the coating viscosity to ensure the coatability of the colloid;

[0023] (2) By matching the hard and soft monomers, the pressure-sensitive adhesive of the present invention enables the pressure-sensitive adhesive product to have good pressure sensitivity;

[0024] (3) The preparation method of the pressure-sensitive adhesive of the present invention is a solvent-free synthesis method, which can coat a pressure-sensitive adhesive with a relatively high thickness. The thick adhesive has a better fitting effect on the chip, thereby enhancing the protection effect on the chip.

[0025] In the ranges disclosed herein, the endpoints and any values are not limited to the exact ranges or values. These ranges or values should be understood to include values close to these ranges or values. For numerical ranges, between the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values, they can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein. Description of the Drawings

[0026] Figure 1 The picture shows the pressure-sensitive tape of the present invention without residual glue after high-temperature baking.

[0027] Figure 2 The picture shows the residual glue of the pressure-sensitive tape in the prior art after high-temperature baking.

[0028] Figure 3 The figure shows a schematic diagram of the preparation process of the pressure-sensitive adhesive product of the present invention.

[0029] Reference Signs

[0030] 1-1, the first tape; 1-2, the second tape; 2-1, the substrate. Detailed Embodiments

[0031] The following provides a detailed description of the specific embodiments of the present invention. It should be understood that the specific embodiments described herein are only for the purpose of illustrating and explaining the present invention, and are not intended to limit the present invention.

[0032] In the first aspect of the present invention, a pressure-sensitive adhesive composition is provided, which comprises the following raw materials: a soft monomer, optionally a hard monomer, a functional monomer, a photoinitiator, and a chain transfer agent; the functional monomer comprises a first functional monomer and a second functional monomer, and the first functional monomer and the second functional monomer are different.

[0033] The term "soft monomer" refers to a monomer with a relatively low glass transition temperature of its homopolymer. Generally, a monomer with a glass transition temperature between -20°C and -70°C is called a soft monomer. The term "hard monomer" is a monomer with a relatively high glass transition temperature of its homopolymer. For example, a monomer with a glass transition temperature higher than 0°C is called a hard monomer.

[0034] In the present invention, the "functional monomer" refers to a monomer containing different functional groups.

[0035] The inventors of the present invention have found that the components in the pressure-sensitive composition have a synergistic effect. On the one hand, the functional monomers with different functional groups are used in combination, which can provide multiple reaction points to form a network structure, thereby improving the crosslinking density of the pressure-sensitive adhesive, enhancing the high-temperature resistance of the pressure-sensitive adhesive, balancing the viscosity during the coating of the pressure-sensitive adhesive, ensuring the coatability of the pressure-sensitive adhesive, and ensuring the cohesion of the pressure-sensitive adhesive product. On the other hand, the combination of the soft monomer and the hard monomer can make the pressure-sensitive adhesive have good pressure sensitivity.

[0036] In one example, the mass ratio of the first functional monomer to the second functional monomer is 1:(0.1 - 10), preferably 1:(0.2 - 5). Optimizing the mass ratio of the two can make the combined use effect of the first functional monomer and the second functional monomer better, thereby enhancing the high-temperature resistance of the pressure-sensitive adhesive.

[0037] In one example, the first functional monomer and the second functional monomer are each independently selected from one or more of monofunctional or polyfunctional acrylates, monofunctional or polyfunctional urethane acrylates, monofunctional N-vinylpyrrolidone, monofunctional (meth)acrylic glycidyl ester, bifunctional N-hydroxymethylacrylamide, bifunctional polyethylene glycol dimethacrylate, bifunctional divinylbenzene, and bifunctional 1,6-hexanediol diacrylate.

[0038] In one example, the monofunctional or polyfunctional acrylate includes bifunctional tricyclodecane dimethanol diacrylate (SR833NS), bifunctional 1,6-hexanediol diacrylate (SR238), and monofunctional caprolactone acrylate (SR495BNS).

[0039] In one example, the mono-functional or multi-functional polyurethane acrylate includes hexafunctional aliphatic polyurethane acrylate (CN9010NS), difunctional polyurethane acrylate (CN983NS), bifunctional polyurethane acrylate (CN966J75), and trifunctional aliphatic polyurethane acrylate (CN989NS).

[0040] In one example, the first functional monomer and the second functional monomer are each independently selected from hexafunctional aliphatic polyurethane acrylate (CN9010NS), monofunctional caprolactone acrylate (SR495BNS), bifunctional tricyclodecane dimethanol diacrylate (SR833NS), difunctional polyurethane acrylate (CN983NS), bifunctional polyurethane acrylate (CN966J75), and trifunctional aliphatic polyurethane acrylate (CN989NS).

[0041] In one example, the functional monomer includes a monofunctional monomer. Adding the monofunctional monomer can play a diluting role to reduce the viscosity of the prepolymer, making it more suitable for industrial coating. At the same time, the monofunctional monomer can also participate in the later reaction, so there is no additional residue.

[0042] In one example, the mass ratio of the soft monomer, the hard monomer, and the functional monomer is 1:(0 - 0.14):(0.01 - 0.14).

[0043] In one example, the mass ratio of the soft monomer, the hard monomer, and the functional monomer is 1:(0 - 0.1):(0.01 - 0.1).

[0044] In one example, the soft monomer is one or more of butyl acrylate, isooctyl acrylate, ethyl acrylate, n-octyl acrylate, 2-hydroxyethyl acrylate, lauryl acrylate, and lauryl methacrylate.

[0045] In one example, the soft monomer is isooctyl acrylate and / or 2-hydroxyethyl acrylate.

[0046] In one example, the hard monomer is one or more of methyl methacrylate, styrene, acrylic acid, vinyl acetate, ethyl methacrylate, isobutyl methacrylate, acrylonitrile, cyclohexyl methacrylate, and isobornyl methacrylate.

[0047] In one example, the hard monomer is acrylic acid.

[0048] The inventors of the present invention have found through research that among the combined use of numerous soft monomers and hard monomers, when the soft monomer isooctyl acrylate and the hard monomer acrylic acid are used in combination at a ratio of (15 - 24):1, a pressure-sensitive adhesive with relatively high cohesive strength and good high-temperature resistance can be obtained.

[0049] In one example, the chain transfer agent is one or two of isooctyl 3 - mercaptopropionate, n - dodecyl mercaptan (NDM), and tert - dodecyl mercaptan. The chain transfer agent in the present invention is used to adjust the relative molecular mass of the polymer, that is, to control the chain length of the polymer, and thus to control the degree of polymerization of the polymer or the viscosity of the polymer.

[0050] In one example, the pressure - sensitive adhesive composition further includes a silane coupling agent and an antistatic agent.

[0051] Adding a coupling agent to the pressure - sensitive adhesive composition can increase the adhesiveness of the pressure - sensitive adhesive. For example, adding a silane coupling agent to the pressure - sensitive adhesive composition can increase its adhesiveness on the glass surface. Adding an antistatic agent to the pressure - sensitive adhesive composition can increase the antistatic property of the pressure - sensitive adhesive.

[0052] In one example, the silane coupling agent includes one or more of KH560 γ - glycidoxypropyltrimethoxysilane, KH570 γ - methacryloxypropyltrimethoxysilane, KH792, and DL602.

[0053] In one example, the antistatic agent includes one or more of polythiophene - based TFSI, amphoteric imidazoline type, hydroxyethylalkylamine, fatty acid amides, polyoxyethylene type, polyol esters, polyethers, quaternary ammonium salts, sulfonates, and betaines.

[0054] In one example, the photoinitiator includes a first photoinitiator, a second photoinitiator, and a third photoinitiator.

[0055] In one example, the second photoinitiator is the same as the first photoinitiator, and the third photoinitiator is different from the first photoinitiator. By using different types of photoinitiators in combination, the composition can be cured at different wavelengths.

[0056] In one example, the photoinitiator includes one or more of benzoin and its derivatives, benzil derivatives, acetophenone derivatives, α - hydroxyalkyl phenyl ketones, α - amino ketone derivatives, and acylphosphine oxides.

[0057] In one example, the acetophenone derivative includes 1 - hydroxycyclohexyl phenyl ketone (184).

[0058] In one example, the acylphosphine oxide is trimethylbenzoyl - diphenylphosphine oxide (TPO).

[0059] The inventors of the present invention found that adding the photoinitiator TPO to the pressure - sensitive adhesive composition of the present invention can enable the pressure - sensitive adhesive composition of the present invention to still have good photo - curing ability even at a relatively high thickness.

[0060] In a second aspect of the present invention, there is provided a pressure-sensitive adhesive, comprising the pressure-sensitive adhesive composition described in the first aspect of the present invention, or obtained by preparing from the pressure-sensitive adhesive composition.

[0061] In a third aspect of the present invention, there is provided a method for preparing the pressure-sensitive adhesive described in the second aspect of the present invention, comprising the following steps:

[0062] (1) In the presence of a first light source and an inert gas, mixing a soft monomer, optionally a hard monomer, a first photoinitiator and a chain transfer agent to obtain a prepolymer;

[0063] (2) In a light-shielded environment, adding a first functional monomer, a second functional monomer, a second photoinitiator, a third photoinitiator, a silane coupling agent and an antistatic agent to the prepolymer obtained in step (1) and mixing uniformly.

[0064] In one example, based on the total weight of the prepolymer, the content of the first functional monomer is 1-10%, and the content of the second functional monomer is 1-10%.

[0065] In one example, the mass ratios of the components in step (1) are as follows: 70-95 parts by weight of the soft monomer, 0-10 parts by weight of the hard monomer. Since the pressure-sensitive adhesive also contains other components, the limitation of each component does not meet the percentage requirement for component limitation; based on the total weight of the soft monomer and the hard monomer being 100 parts by weight, 0.01-0.1 part by weight of the first photoinitiator and 0.01-0.5 part by weight of the chain transfer agent.

[0066] In one example, based on the total weight of the prepolymer obtained in step (1) being 100 parts by weight, the mass ratios of the components in step (2) are as follows: 100 parts by weight of the prepolymer, 1-10 parts by weight of the first functional monomer, 1-10 parts by weight of the second functional monomer, 0.01-0.1 part by weight of the second photoinitiator, 0.01-0.1 part by weight of the third initiator, 0.01-1 part by weight of the silane coupling agent, and 0.01-1 part by weight of the antistatic agent.

[0067] In one example, the inert gas is nitrogen or argon, preferably nitrogen.

[0068] In one example, the reaction temperature of step (1) is 5-25°C, and the reaction conversion rate is controlled at 10-40%.

[0069] In one example, the first light source in step (1) is ultraviolet light.

[0070] The first light source can be provided by a mercury lamp.

[0071] In one example, the intensity of the first light source is 30-40 W.

[0072] In step (1), the reaction degree is controlled by controlling the change of reaction temperature, and the intensity of the first light source is maintained between 30 - 40 W to promote the polymerization reaction of the soft monomer and the hard monomer.

[0073] The fourth aspect of the present invention provides a pressure - sensitive adhesive product, including at least one of the pressure - sensitive adhesive composition described in the first aspect of the present invention, the pressure - sensitive adhesive described in the second aspect of the present invention, and the pressure - sensitive adhesive prepared by the method described in the third aspect of the present invention.

[0074] There is no limitation on the specific product form of the pressure - sensitive adhesive product, as long as it contains the pressure - sensitive adhesive of the present invention.

[0075] In one example, the pressure - sensitive adhesive product is a pressure - sensitive adhesive tape.

[0076] The preparation method of the pressure - sensitive adhesive product includes using the pressure - sensitive adhesive prepared in the third aspect of the present invention to continue the following steps:

[0077] (3) Use the pressure - sensitive adhesive obtained in step (2) to be evenly coated between the release layers pre - coated with a release agent by a coater, and perform UV irradiation with a second light source, then transfer the obtained first tape 1 - 1 (such as Figure 3 in I) to one side of the substrate 2 - 1 (such as Figure 3 in II);

[0078] (4) Repeat step (3) to transfer the obtained second tape 1 - 2 to the other side of the substrate 2 - 1 to obtain the pressure - sensitive adhesive product (such as Figure 3 shown in III).

[0079] In one example, the second light source in step (3) is ultraviolet light.

[0080] In one example, the energy density of the second light source is 500 - 3,000 mj / cm 2 . In step (3), the energy of the ultraviolet light is controlled by controlling the energy density, thereby controlling the curing time of the pressure - sensitive adhesive.

[0081] In one example, the substrate is polyimide.

[0082] In one example, the release layer is a release film or a release paper.

[0083] Preferably, the release film is a polyethylene terephthalate (PET) release film.

[0084] Preferably, the release paper is cotton paper.

[0085] In one example, the thickness of the pressure-sensitive adhesive product is 70 μm - 700 μm (such as 70 μm, 80 μm, 90 μm, 100 μm, 150 μm, 200 μm, 250 μm, 300 μm, 350 μm, 400 μm, 450 μm, 500 μm, 550 μm, 600 μm, 610 μm, 620 μm, 630 μm, 640 μm, 650 μm, 660 μm, 670 μm, 680 μm, 690 μm, 700 μm), preferably 400 μm - 700 μm.

[0086] The pressure-sensitive adhesive tape prepared by the present invention can withstand the high temperature of wave soldering and reflow soldering, has the functions of high-temperature shielding and component fixing, and can be used in the surface mount technology (SMT) in the production processes of flexible printed circuit boards (FPC) and printed circuit boards (PCB).

[0087] The present invention tests the performance of the pressure-sensitive adhesive tape according to the following test methods:

[0088] Peel force test: Refer to GB / T 2792-2014 "Test Method for Peel Strength of Adhesive Tapes".

[0089] Temperature resistance test: Tear off the release film on one side, attach the chip, roll press (30 kg, 15 s), put it into an oven at 200 °C for 1 h, take it out and place it at room temperature for 30 min, tear open the double-sided adhesive tape, and observe the residual glue on the chip with a 10-fold CDD.

[0090] Adhesive surface impedance: Test using a Trek 152-1 heavy hammer type impedance tester.

[0091] The adhesive surface impedance value is within the range of 1×10 4 -1×10 9 It indicates that the antistatic performance of the pressure-sensitive adhesive product is relatively good.

[0092] Thickness: Test using a Mitutoyo 547-401 thickness tester.

[0093] ΔE: Use an LS171 color difference meter to test its haze.

[0094] The haze ΔE value < 0.5 indicates that the chromaticity difference of the pressure-sensitive adhesive product after high-temperature baking is small and there is no yellowing situation.

[0095] In the invention, ordinal numbers such as "first" and "second" are not used to represent order, but are only used to distinguish different objects and / or different usage environments.

[0096] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0097] Example 1

[0098] Ratio of pressure-sensitive adhesive composition:

[0099] Soft monomer: 95 parts by weight of isooctyl acrylate;

[0100] Hard monomer: 5 parts by weight of acrylic acid;

[0101] Chain transfer agent: 0.015 parts by weight of NDM;

[0102] First photoinitiator: 0.05 parts by weight of 184;

[0103] First functional monomer: 2 parts by weight of CN9010NS;

[0104] Second functional monomer: 1 part by weight of SR495BNS;

[0105] Second photoinitiator: 0.05 parts by weight of 184;

[0106] Third photoinitiator: 0.05 parts by weight of TPO;

[0107] Silane coupling agent: 0.5 parts by weight of KH560;

[0108] Antistatic agent: 0.2 parts by weight of TFSI.

[0109] Preparation of pressure-sensitive tape:

[0110] (1) Add the soft monomer, hard monomer, first photoinitiator and chain transfer agent into a reaction flask, stir evenly, pass nitrogen for 20 min to remove oxygen, place the reaction device in a light-shielded environment, keep the UV LED light source 10 cm away from the reaction flask, turn on the light source for irradiation, record the initial temperature of the reaction liquid, start the reaction and raise the temperature, control the reaction temperature to rise by 15 °C, control the reaction conversion rate to 25%, stop the reaction, and obtain a high-temperature resistant pressure-sensitive adhesive glue prepolymer;

[0111] (2) Take 100 parts by weight of the obtained prepolymer, add the first functional monomer, second functional monomer, second photoinitiator, third photoinitiator, silane coupling agent and antistatic agent, stir evenly in a light-shielded environment, and perform vacuum degassing to obtain a radiation-curable high-temperature resistant pressure-sensitive adhesive;

[0112] (3) The pressure-sensitive adhesive is evenly coated between the PET release films pre-coated with a release agent, and the thickness is controlled at 350 μm. Then, it is irradiated with UV light under the second light source, and the light energy is 2500 mj / cm 2 . One layer of the release film is peeled off and adhered to one side of the polyimide substrate, and the other side is repeatedly coated with an adhesive layer and adhered, thus obtaining a high-temperature resistant pressure-sensitive tape.

[0113] Example 2:

[0114] It is basically the same as Example 1, except that the types or ratios of the following compositions are changed:

[0115] Soft monomer: 90 parts by weight of isooctyl acrylate, 5 parts by weight of 2-hydroxyethyl acrylate;

[0116] Hard monomer: 5 parts by weight of acrylic acid;

[0117] Chain transfer agent: 0.01 part by weight of NDM;

[0118] First photoinitiator: 0.03 part by weight of 184.

[0119] First functional monomer: 3 parts by weight of SR833NS;

[0120] Second functional monomer: 1 part by weight of CN983NS.

[0121] Example 3:

[0122] It is basically the same as Example 1, except that the types or ratios of the following compositions are changed:

[0123] Soft monomer: 96 parts by weight of hydroxybutyl acrylate;

[0124] Hard monomer: 4 parts by weight of styrene;

[0125] Chain transfer agent: 0.01 part by weight of NDM;

[0126] First photoinitiator: 0.02 part by weight of 184.

[0127] First functional monomer: 1 part by weight of CN966J75;

[0128] Second functional monomer: 2 parts by weight of CN989NS.

[0129] Example 4

[0130] Example 4 is used to illustrate the influence of the ratios of soft monomers, hard monomers, and functional monomers on the experimental results.

[0131] Example 4a

[0132] It is basically the same as Example 1, except that the ratios of the soft monomer, hard monomer, and functional monomer are different. Specifically: the first functional monomer: CN9010NS 7.5 parts by weight; the second functional monomer: SR495BNS 1.5 parts by weight.

[0133] Example 4b

[0134] It is basically the same as Example 1, except that the ratios of the soft monomer and hard monomer are different. Specifically, the soft monomer: isooctyl acrylate 90 parts by weight; the hard monomer: acrylic acid 10 parts by weight.

[0135] Example 4c

[0136] It is basically the same as Example 1, except that the ratios of the first functional monomer and the second functional monomer are different. Specifically, the first functional monomer: CN9010NS 6 parts by weight; the second functional monomer: SR495BNS 1 part by weight.

[0137] Example 5

[0138] Example 5 is used to illustrate the influence of the change in the types of the first functional monomer and the second functional monomer on the experimental results.

[0139] It is basically the same as Example 1, except that the first functional monomer is replaced by 1,6 - hexanediol diacrylate, and the second functional monomer is replaced by N - vinylpyrrolidone.

[0140] Example 6

[0141] Example 6 is used to illustrate the influence of the soft monomer and the hard monomer on the experimental results.

[0142] It is basically the same as Example 1, except that the soft monomer is n - octyl acrylate and the hard monomer is methyl methacrylate.

[0143] Example 7

[0144] It is basically the same as Example 1, except that the hard monomer is not included in the components.

[0145] Comparative Example 1

[0146] It is basically the same as Example 1, except that only one functional monomer, SR833NS 4 parts by weight, is added in step (2).

[0147] Comparative Example 2

[0148] It is basically the same as Example 1, except that no functional monomer is added in step (2).

[0149] Comparative Example 3

[0150] It is basically the same as Example 1, except that the mass ratio of the first functional monomer to the second monomer is 1:0.05.

[0151] Comparative Example 4

[0152] It is basically the same as Example 1, except that the mass ratio of the first functional monomer to the second monomer is 1:11.

[0153] Test Example

[0154] Peeling force test: Refer to GB / T 2792-2014 "Test Method for Peeling Strength of Adhesive Tapes".

[0155] Temperature resistance test: Tear off the release film on one side, bond the chip, roll press (30 kg, 15 s), place it in an oven at 200 °C for 1 h, take it out and place it at room temperature for 30 min, tear off the double-sided tape, and observe the residual glue on the chip with a 10-fold CDD.

[0156] Adhesive surface impedance: Test using a Trek 152-1 heavy hammer type impedance tester.

[0157] Thickness: Test using a Mitutoyo 547-401 thickness tester.

[0158] ΔE: Test its haze using an LS171 color difference meter.

[0159] The situation of the pressure-sensitive tape of the present invention in actual high-temperature environment use is as Figure 1 shown, and there is no residual glue phenomenon. While the situation of the pressure-sensitive tape in the prior art in use is as Figure 2 shown, and obvious residual glue can be seen. The test results are shown in Table 1.

[0160] Table 1

[0161]

[0162]

[0163] It can be seen from the above experimental results that the pressure-sensitive adhesive products prepared by adopting the technical solution of the present invention have good high-temperature resistance. After the products are baked at high temperature and torn off, there is no residual glue on the surface, and the color change difference of the products before and after baking is small, without yellowing; and from the test data of Comparative Example 1 and Comparative Example 2, it can be known that when only one functional monomer is included and no functional monomer is included, the peeling force of the product is high and the residual glue is serious, which is not conducive to actual application; and from Comparative Example 3 and Comparative Example 4, it can be known that when the mass ratio of the first functional monomer to the second functional monomer is higher than 1:0.1, the peeling force of the product is high and the surface residual glue is serious, and when the mass ratio of the first functional monomer to the second functional monomer is lower than 1:10, the peeling force of the product is too small and it is easy to fall off from the applied chip, which is not conducive to actual application.

[0164] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including the combination of each technical feature in any other suitable manner. These simple modifications and combinations should also be regarded as the content disclosed by the present invention and fall within the protection scope of the present invention.

Claims

1. A pressure-sensitive adhesive composition, characterized in that, It comprises the following raw materials: soft monomer, optionally hard monomer, functional monomer, photoinitiator and chain transfer agent; The functional monomer comprises a first functional monomer and a second functional monomer, and the first functional monomer is different from the second functional monomer; The first functional monomer and the second functional monomer are each independently selected from at least one of monofunctional or polyfunctional acrylate, and monofunctional or polyfunctional polyurethane acrylate; The monofunctional or polyfunctional acrylate is at least one of bifunctional tricyclodecane dimethanol diacrylate and monofunctional caprolactone acrylate; The mass ratio of the first functional monomer to the second functional monomer is 1:(0.1 - 10).

2. The pressure-sensitive adhesive composition according to claim 1, wherein, The mass ratio of the first functional monomer to the second functional monomer is 1:(0.2 - 5).

3. The pressure-sensitive adhesive composition according to claim 1, wherein The mass ratio of the soft monomer, hard monomer and functional monomer is 1:(0 - 0.14):(0.01 - 0.14).

4. The pressure-sensitive adhesive composition according to claim 1, wherein, The soft monomer is one or more of butyl acrylate, isooctyl acrylate, ethyl acrylate, n-octyl acrylate, 2-hydroxyethyl acrylate, lauryl acrylate and lauryl methacrylate; and / or The hard monomer is one or more of methyl methacrylate, styrene, acrylic acid, vinyl acetate, ethyl methacrylate, isobutyl methacrylate, acrylonitrile, cyclohexyl methacrylate and isobornyl methacrylate.

5. The pressure-sensitive adhesive composition according to claim 1, wherein, The photoinitiator comprises a first photoinitiator, a second photoinitiator and a third photoinitiator; the second photoinitiator is the same as the first photoinitiator, and the third photoinitiator is different from the first photoinitiator.

6. The pressure-sensitive adhesive composition according to any one of claims 1-5, wherein, The pressure-sensitive adhesive composition further comprises a silane coupling agent and an antistatic agent.

7. A pressure-sensitive adhesive, characterized in that, It comprises the pressure-sensitive adhesive composition according to any one of claims 1 - 6, or is prepared from the pressure-sensitive adhesive composition.

8. A method for preparing the pressure-sensitive adhesive according to claim 7, characterized in that, It comprises the following steps: (1) In the presence of a first light source and an inert gas, the soft monomer, optionally the hard monomer, the first photoinitiator and the chain transfer agent are mixed to obtain a prepolymer; (2) In a light-shielded environment, the first functional monomer, the second functional monomer, the second photoinitiator, the third photoinitiator, the silane coupling agent and the antistatic agent are added to the prepolymer obtained in step (1) and mixed evenly.

9. A pressure-sensitive adhesive article, characterized in that, It comprises at least one of the pressure-sensitive adhesive composition according to any one of claims 1 - 6, the pressure-sensitive adhesive according to claim 7, and the pressure-sensitive adhesive prepared by the method according to claim 8.

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