Preparation method of acid and alkali resistant acrylate adhesive and preparation method of pressure-sensitive adhesive tape

Abstract

The invention provides a preparation method of an acid and alkali resistant acrylate adhesive and a preparation method of a pressure-sensitive adhesive tape. The preparation method comprises the following steps: mixing 30-60 parts of an acrylate soft monomer, 10-30 parts of an acrylate hard monomer, 2-10 parts of an acrylate functional monomer, 0.01-0.5 part of an initiator and a solvent; supplementing an initiator, and carrying out heat preservation reaction; diluting to obtain acrylic resin; adding a curing agent and mixing to obtain an acrylate adhesive precursor; adding 1-10 parts of polybenzoxazole fibers, 1-10 parts of a silane coupling agent and a solvent to obtain an acid and alkali resistant acrylate adhesive; and coating the acid and alkali resistant acrylate adhesive on a base material to obtain the acid and alkali resistant acrylate pressure-sensitive adhesive tape. The acid and alkali resistant acrylate adhesive and the pressure-sensitive adhesive tape prepared by the invention have excellent acid and alkali resistance, the acid and alkali resistant pressure-sensitive adhesive tape can effectively protect an electronic element from being corroded by acid and alkali, the edge of the pressure-sensitive adhesive tape is free of upwarp and bubbles, and no adhesive residue exists after a film is uncovered.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electronic semiconductor technology, in particular to a preparation method of acid and alkali resistant acrylic adhesive and a preparation method of pressure sensitive adhesive tape. BACKGROUND

[0002] Pressure sensitive adhesive is a kind of adhesive that can be firmly bonded with the adherend without the aid of solvent, heat or other means, only by applying light pressure. Pressure sensitive adhesive is characterized by easy bonding and easy peeling. The adhesive layer will not dry in a long period of time, so pressure sensitive adhesive is also called non-drying adhesive. Due to the characteristics of pressure sensitive adhesive, its products are widely used in packaging, printing, medical, home appliance industry and manufacturing industry and other fields.

[0003] Pressure sensitive adhesive is various, and can be divided into many types according to different classification standards. The common classification is to divide it into two categories of rubber series and resin series according to the composition of the main body material of pressure sensitive adhesive, and further can be divided into rubber type pressure sensitive adhesive, thermoplastic elastomer type pressure sensitive adhesive, acrylic ester type pressure sensitive adhesive, organic silicon type pressure sensitive adhesive and polyurethane type pressure sensitive adhesive. Among them, acrylic ester type pressure sensitive adhesive is the current research and development hotspot.

[0004] In the field of electronics, semiconductors and other fields, pressure sensitive adhesive tape is an indispensable consumable in production and manufacturing process. Chip photolithography, etching and other processes have nanometer level precision, and pressure sensitive adhesive tape is needed to accurately shield the non-processing area of electronic components to avoid acid erosion of the circuit or structure. In the process, hydrofluoric acid, sulfuric acid, KOH, NaOH and other acid and alkali solutions are often used for etching. Ordinary adhesive tape is prone to residual glue, acid penetration and even corrosion failure. At the same time, electronic components are easy to be oxidized and short-circuited when contacting acid and alkali. Therefore, pressure sensitive adhesive tape with excellent acid and alkali resistance is urgently needed to protect electronic components in various use scenarios.

[0005] In view of this, the present application is proposed. SUMMARY

[0006] The present application aims at the deficiencies of the prior art, and provides a preparation method of acid and alkali resistant acrylic adhesive and a preparation method of pressure sensitive adhesive tape. The acid and alkali resistant acrylic adhesive and the pressure sensitive adhesive tape prepared by the method have excellent acid and alkali resistance. The acid and alkali resistant pressure sensitive adhesive tape can effectively protect electronic components from being corroded by acid and alkali. The edge of the pressure sensitive adhesive tape has no lifting and no bubbles. There is no residual glue after peeling off the film. The technical problem of poor acid and alkali resistance and easy corrosion of the existing acrylic pressure sensitive adhesive is solved.

[0007] In order to achieve the above-mentioned purpose of the present application, the following technical scheme is adopted: A preparation method of acid and alkali resistant acrylic adhesive, comprising the following steps: Step S1, by weight parts, acrylic ester soft monomer 30~60 parts, acrylic ester hard monomer 10~30 parts, acrylic ester functional monomer 2~10 parts, A group initiator 0.01~0.5 parts and A group first solvent are mixed to obtain monomer mixed solution; Step S2, after warming under inert atmosphere, add B group initiator 0.01~0.5 parts by weight parts, heat preservation reaction, to obtain acrylic resin precursor; Step S3, add B group first solvent dilution, to obtain acrylic resin; Step S4, add curing agent 0.1~2 parts by weight parts, to obtain acrylic ester adhesive precursor; Step S5, add polybenzoxazole fiber 1~10 parts, silane coupling agent 1~10 parts and second solvent by weight parts, uniformly dispersed, to obtain acid and alkali resistant type acrylic ester adhesive.

[0008] Further, the inert atmosphere in step S2 is one or a combination of nitrogen, argon, helium, neon, krypton.

[0009] Further, the temperature in step S2 is raised to 75~85℃.

[0010] Further, the reaction time in step S2 is 3~4h.

[0011] Further, in step S3, the B group first solvent is added to dilute, to obtain acrylic resin with solid content of 30%~50%.

[0012] Further, the polybenzoxazole fiber in step S5 is surface pretreated to introduce hydroxyl groups.

[0013] Further, the acrylic ester soft monomer in step S1 is one or more of ethyl acrylate, n-butyl acrylate, isooctyl acrylate, lauryl methacrylate.

[0014] Further, the acrylic ester hard monomer in step S1 is one or more of methyl acrylate, methyl methacrylate, styrene, vinyl acetate, cyclohexyl acrylate.

[0015] Further, the acrylic ester functional monomer in step S1 is one or more of 2-hydroxyethyl methacrylate, glycidyl methacrylate, isobornyl acrylate, acrylic acid, itaconic acid.

[0016] Further, the A group initiator in step S1 is one or more of dibenzoyl peroxide, azobisisobutyronitrile, V-601.

[0017] Further, the B group initiator in step S2 is one or more of dibenzoyl peroxide, azobisisobutyronitrile, V-601.

[0018] Further, the first solvent of group A in step S1 is one or more of toluene, ethyl acetate, acetone, butyl acetate.

[0019] Further, the first solvent of group B in step S3 is one or more of toluene, ethyl acetate, acetone, butyl acetate.

[0020] Further, the curing agent in step S4 is one or more of toluene diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, 4,4-dicyclohexylmethane diisocyanate, p-toluenesulfonyl isocyanate.

[0021] Further, the silane coupling agent in step S5 is one or more of gamma-aminopropyl triethoxysilane, gamma-methacryloyloxypropyl trimethoxysilane, gamma-mercaptopropyl trimethoxysilane, gamma-mercaptopropyl triethoxysilane.

[0022] Further, the second solvent in step S5 is one or more of ethanol, isopropyl alcohol, ethylene glycol, glycerol.

[0023] The acid and alkali resistant type acrylate adhesive prepared by the preparation method of the acid and alkali resistant type acrylate adhesive.

[0024] A preparation method of an acid and alkali resistant type acrylate pressure-sensitive adhesive tape, which uniformly coats the acid and alkali resistant type acrylate adhesive on a substrate to obtain an acid and alkali resistant type acrylate pressure-sensitive adhesive tape.

[0025] The acid and alkali resistant type acrylate pressure-sensitive adhesive tape prepared by the preparation method of the acid and alkali resistant type acrylate pressure-sensitive adhesive tape.

[0026] Compared with the prior art, the acid and alkali resistant type acrylate adhesive and the preparation method of the acid and alkali resistant type acrylate pressure-sensitive adhesive tape have the following beneficial effects: 1. The acid and alkali resistant type acrylate adhesive and the preparation method of the acid and alkali resistant type acrylate pressure-sensitive adhesive tape, the added polybenzoxazole fiber has a stable chemical structure and excellent corrosion resistance, and the polybenzoxazole can form a chemical cross-linking structure and a hydrogen bond with the acrylate, further improving the acid and alkali resistance of the acrylate adhesive.

[0027] 2. The acid and alkali resistant type acrylate adhesive and the preparation method of the acid and alkali resistant type acrylate pressure-sensitive adhesive tape, the polybenzoxazole fiber and the silane coupling agent are added at the same time, the polybenzoxazole fiber is bridged with the acrylate adhesive, the compatibility of the two is promoted, the problem of poor compatibility of the polybenzoxazole fiber and the acrylic resin is solved, the bonding function of the acrylate adhesive is maintained, the consistency and stability of the bonding performance of the adhesive are ensured, and the acrylate adhesive and the acid and alkali resistant type acrylate pressure-sensitive adhesive tape with excellent acid and alkali resistance are obtained.

[0028] 3. The polybenzoxazole fiber of the present application is subjected to surface pretreatment by UV irradiation or strong alkali to introduce hydroxyl groups. The polybenzoxazole (PBO) fiber after surface treatment reacts with the siloxyl group at one end of the silane coupling agent, while the acrylic resin reacts with the other end of the silane coupling agent, forming a chemical bridge of "PBO fiber-silane coupling agent-acrylic resin". BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the specific embodiments of the present application or the prior art, the drawings needed in the specific embodiments or prior art description will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without making any creative effort.

[0030] Figure 1 DSC curves of the acid and alkali resistant acrylate adhesives prepared for Examples 1-6 of the present application; Figure 2 DSC curves of the acrylate adhesives prepared for Comparative Examples 1-4 of the present application; Figure 3 Photos of wafers (unpeeled) after immersion in acid and alkali solutions for the acrylate pressure-sensitive adhesive tape prepared for Comparative Example 1 of the present application and adhered to the wafer; Figure 4 Photos of wafers (unpeeled) after immersion in acid and alkali solutions for the acrylate pressure-sensitive adhesive tape prepared for Comparative Example 2 of the present application and adhered to the wafer; Figure 5 Photos of wafers (unpeeled) after immersion in acid and alkali solutions for the acrylate pressure-sensitive adhesive tape prepared for Comparative Example 3 of the present application and adhered to the wafer Figure 6 Photos of wafers (after peeling) after immersion in acid and alkali solutions for the acrylate pressure-sensitive adhesive tape prepared for Comparative Example 3 of the present application and adhered to the wafer. DETAILED DESCRIPTION

[0031] The technical solutions of the present application will be described below in conjunction with specific embodiments, but those skilled in the art will understand that the following described embodiments are part of the embodiments of the present application, not all the embodiments, and should not be regarded as limiting the scope of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making any creative effort are within the scope of protection of the present application. The specific conditions are not specified in the embodiments, which are carried out according to the conventional conditions or the conditions recommended by the manufacturer. The reagents or instruments used are not specified by the manufacturer, which are conventional products that can be purchased on the market.

[0032] A preparation method of an acid and alkali resistant type acrylic adhesive, comprising the following steps: Step S1, the acrylic ester soft monomer 30-60 parts (including but not limited to 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, 55 parts, 60 parts), the acrylic ester hard monomer 10-30 parts (including but not limited to 10 parts, 15 parts, 20 parts, 25 parts, 30 parts), the acrylic ester functional monomer 2-10 parts (including but not limited to 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts), the A group initiator 0.01-0.5 parts (including but not limited to 0.01 parts, 0.02 parts, 0.05 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts) and the A group first solvent 50-100 parts (including but not limited to 50 parts, 60 parts, 70 parts, 80 parts, 90 parts, 100 parts) are mixed according to weight parts, and a monomer mixed solution is obtained; Step S2, after warming up under inert atmosphere, the B group initiator 0.01-0.5 parts (including but not limited to 0.01 parts, 0.02 parts, 0.05 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts) is supplemented according to weight parts, and the reaction is kept warm to obtain an acrylic resin precursor; Step S3, the B group first solvent is added for dilution to obtain an acrylic resin; Step S4, the curing agent 0.1-2 parts (including but not limited to 0.1 parts, 0.2 parts, 0.5 parts, 1 parts, 1.5 parts, 2 parts) is added according to weight parts, mixed and stirred uniformly to obtain an acrylic ester adhesive precursor; Step S5, the polybenzoxazole fiber 1-10 parts (including but not limited to 1 parts, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts), the silane coupling agent 1-10 parts (including but not limited to 1 parts, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts) and the second solvent 20-30 parts (including but not limited to 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, 30 parts) are added according to weight parts, and are uniformly dispersed to obtain an acid and alkali resistant type acrylic adhesive; Preferably, the inert atmosphere in step S2 is one or a combination of nitrogen, argon, helium, neon and krypton; Preferably, the temperature in step S2 is raised to 75-85 DEG C, including but not limited to 75 DEG C, 76 DEG C, 77 DEG C, 78 DEG C, 79 DEG C, 80 DEG C, 81 DEG C, 82 DEG C, 83 DEG C, 84 DEG C, 85 DEG C; Preferably, the reaction time in step S2 is 3-4 h, including but not limited to 3 h, 3 h 10 min, 3 h 20 min, 3 h 30 min, 3 h 40 min, 3 h 50 min, 4 h; Preferably, in step S3, 50 to 100 parts (including but not limited to 50 parts, 60 parts, 70 parts, 80 parts, 90 parts, 100 parts) of the first solvent of group B are added for dilution to obtain an acrylic resin with a solid content of 30% to 50% (including but not limited to 30%, 35%, 40%, 45%, 50%); Preferably, in step S5, the polybenzoxazole fiber is surface pretreated to introduce hydroxyl groups; Preferably, the surface pretreatment is a surface treatment performed by ultraviolet light irradiation or strong alkali action; The surface-treated polybenzoxazole (PBO) fiber reacts with the siloxy group at one end of the silane coupling agent to form a hydroxyl reaction, while the acrylic resin reacts with the other end of the silane coupling agent to form a chemical bridge of "PBO fiber-silane coupling agent-acrylic resin"; The chemical bridging process of forming "PBO fiber-silane coupling agent-acrylic resin" in the present invention is mainly divided into three core processes: The first step is that the alkoxy group (-OR) in the silane coupling agent molecule (YR-Si(OR)3) undergoes a hydrolysis reaction to form a silanol group (-Si-OH): YR-Si(OR)3+ R-OH → YR-Si (OH)3+ ROH…Equation 1 Wherein, Y refers to an active group that can react with acrylic resin, such as amino, acryloyloxy, mercapto, etc.; wherein R refers to an alkyl chain, such as methyl (-CH3), ethyl (-C2H5), propyl (-C2H7), etc.; The second step is that the silanol group of the silane coupling agent reacts with the hydroxyl group on the surface of the PBO fiber to form a silicon-oxygen bond (-Si-O-) to achieve chemical connection: YR-Si (OH)3+PBO fiber surface -OH → YR-Si-O-PBO fiber... Equation 2 The third step is the addition reaction between the active groups on the silane and the acrylic resin: YR-Si-O-PBO fiber + CH2 = CH2-COOR → COOR-CH2-CH2-R-Si-O-PBO fiber... Formula 3 COOR-CH2-CH2-R-Si-O-PBO fiber is a chemical bridge of "PBO fiber-silane coupling agent-acrylic resin"; Preferably, the acrylic acid ester soft monomer in step S1 is one or more of ethyl acrylate, n-butyl acrylate, isooctyl acrylate, and lauryl methacrylate; Preferably, the acrylic acid ester hard monomer in step S1 is one or more of methyl acrylate, methyl methacrylate, styrene, vinyl acetate, and cyclohexyl acrylate; Preferably, the acrylic ester functional monomer in step S1 is one or more of 2-hydroxyethyl methacrylate, glycidyl methacrylate, isobornyl acrylate, acrylic acid, itaconic acid; In the synthesis of acrylic resin, the polymerized monomers are widely divided into three categories of hard monomers, soft monomers and functional monomers. Although styrene and vinyl acetate are not acrylic esters, they are often copolymerized with acrylic ester monomers as hard monomers; although itaconic acid is not an acrylic ester monomer, the double bond of itaconic acid can be copolymerized with an acrylic ester monomer as a functional monomer; Preferably, the A group initiator in step S1 is one or more of dibenzoyl peroxide, azobisisobutyronitrile, V-601 (dimethyl azobisisobutyrate initiator). Preferably, the B group initiator in step S2 is one or more of dibenzoyl peroxide, azobisisobutyronitrile, V-601 (dimethyl azobisisobutyrate initiator). Preferably, the A group first solvent in step S1 is one or more of toluene, ethyl acetate, acetone, butyl acetate. Preferably, the B group first solvent in step S3 is one or more of toluene, ethyl acetate, acetone, butyl acetate. Preferably, the curing agent in step S4 is one or more of toluene diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, 4,4-dicyclohexylmethane diisocyanate, p-toluenesulfonyl isocyanate. Preferably, the silane coupling agent in step S5 is one or more of γ-aminopropyl triethoxysilane, γ-methacryloyloxypropyl trimethoxysilane, γ-mercaptopropyl trimethoxysilane, γ-mercaptopropyl triethoxysilane. Preferably, the second solvent in step S5 is one or more of ethanol, isopropyl alcohol, ethylene glycol, glycerol.

[0033] The acid and alkali resistant acrylic adhesive prepared by the preparation method of the acid and alkali resistant acrylic adhesive.

[0034] A preparation method of an acid and alkali resistant acrylic pressure-sensitive adhesive tape, using the acid and alkali resistant acrylic adhesive prepared by the preparation method, uniformly coating the acid and alkali resistant acrylic adhesive on a substrate to obtain an acid and alkali resistant acrylic pressure-sensitive adhesive tape. Preferably, the substrate is one of polyethylene terephthalate (PET), polypropylene (PP), polyolefin composite (PO).

[0035] The acid and alkali resistant acrylic pressure-sensitive adhesive tape prepared by the preparation method of the acid and alkali resistant acrylic pressure-sensitive adhesive tape.

[0036] Example 1 A preparation method of an acid and alkali resistant acrylate adhesive, the formula of acrylate soft monomer, acrylate hard monomer, acrylate functional monomer, initiator, curing agent, first solvent, polybenzoxazole fiber, silane coupling agent and second solvent is shown in Table 1, and the preparation method comprises the following steps: a. The acrylate soft monomer, acrylate hard monomer, acrylate functional monomer, A group initiator and A group first solvent are mixed to obtain a monomer mixed solution; b. After the system is heated to 80°C under a nitrogen atmosphere, the B group initiator is added, and the reaction is kept for 3 hours to obtain an acrylate resin precursor; c. The B group first solvent is added for dilution to obtain an acrylate resin with a solid content of 30%-50%; d. The curing agent is added into the acrylate resin and uniformly stirred to obtain an acrylate adhesive precursor; e. The polybenzoxazole fiber, silane coupling agent and second solvent are added into the acrylate adhesive precursor and uniformly dispersed to obtain an acid and alkali resistant acrylate adhesive.

[0037] The acid and alkali resistant acrylate adhesive is uniformly coated on a 100um PET substrate by a glue coating machine to form a 20um glue layer, then a release film is covered on the glue coating surface, and finally a roll material is wound for use to obtain an acid and alkali resistant acrylate pressure-sensitive adhesive tape.

[0038] Example 2 The difference between this example and Example 1 is that the formula of the acid and alkali resistant acrylate adhesive is different, and the formula is shown in Table 1. The rest is the same as Example 1.

[0039] The acid and alkali resistant acrylate adhesive is uniformly coated on a 100um PET substrate by a glue coating machine to form a 20um glue layer, then a release film is covered on the glue coating surface, and finally a roll material is wound for use to obtain an acid and alkali resistant acrylate pressure-sensitive adhesive tape.

[0040] Example 3 The difference between this example and Example 1 is that the formula of the acid and alkali resistant acrylate adhesive is different, and the formula is shown in Table 1. The rest is the same as Example 1.

[0041] The acid and alkali resistant acrylate adhesive is uniformly coated on a 100um PET substrate by a glue coating machine to form a 20um glue layer, then a release film is covered on the glue coating surface, and finally a roll material is wound for use to obtain an acid and alkali resistant acrylate pressure-sensitive adhesive tape.

[0042] Example 4 The difference between this example and Example 1 is that the formula of the acid and alkali resistant acrylate adhesive is different, and the formula is shown in Table 1. The rest is the same as Example 1.

[0043] The acid and alkali resistant acrylate adhesive is uniformly coated on the 100um PET substrate by the glue coating machine to form a 20um glue layer, then the glue coating surface is covered with a release film, and finally it is rolled into a roll for standby, to obtain an acid and alkali resistant acrylate pressure sensitive adhesive tape.

[0044] Example 5 The difference between this example and Example 1 is that the formula of the acid and alkali resistant acrylate adhesive is different, and the formula is shown in Table 1. The rest is the same as Example 1.

[0045] The acid and alkali resistant acrylate adhesive is uniformly coated on the 100um PET substrate by the glue coating machine to form a 20um glue layer, then the glue coating surface is covered with a release film, and finally it is rolled into a roll for standby, to obtain an acid and alkali resistant acrylate pressure sensitive adhesive tape.

[0046] Example 6 The difference between this example and Example 1 is that the formula of the acid and alkali resistant acrylate adhesive is different, and the formula is shown in Table 1. The rest is the same as Example 1.

[0047] The acid and alkali resistant acrylate adhesive is uniformly coated on the 100um PET substrate by the glue coating machine to form a 20um glue layer, then the glue coating surface is covered with a release film, and finally it is rolled into a roll for standby, to obtain an acid and alkali resistant acrylate pressure sensitive adhesive tape.

[0048] Table 1 Formula table of acid and alkali resistant acrylate adhesive prepared in Examples 1-6 (the unit of each component in the table is g, such as 10 g of ethyl acrylate)

[0049] Comparative Example 1 The difference between this example and Example 1 is that the formula of the acid and alkali resistant acrylate adhesive is different, and the formula is shown in Table 1. The rest is the same as Example 1.

[0050] The acid and alkali resistant acrylate adhesive is uniformly coated on the 100um PET substrate by the glue coating machine to form a 20um glue layer, then the glue coating surface is covered with a release film, and finally it is rolled into a roll for standby, to obtain an acid and alkali resistant acrylate pressure sensitive adhesive tape.

[0051] Comparative Example 2 The difference between this example and Example 1 is that the formula of the acid and alkali resistant acrylate adhesive is different, and the formula is shown in Table 1. The rest is the same as Example 1.

[0052] The above acrylic adhesive was uniformly coated by a coater to form a 20-um adhesive layer on a 100-um PET substrate, then a release film was covered on the adhesive-coated surface, and finally the roll was wound for use, to obtain an acrylic pressure-sensitive adhesive tape.

[0053] Comparative Example 3 The difference between this comparative example and Example 1 is that the formula of the acrylic adhesive is different, see Table 2. The rest is the same as Example 1.

[0054] The above acrylic adhesive was uniformly coated by a coater to form a 20-um adhesive layer on a 100-um PET substrate, then a release film was covered on the adhesive-coated surface, and finally the roll was wound for use, to obtain an acrylic pressure-sensitive adhesive tape.

[0055] Comparative Example 4 The difference between this comparative example and Example 1 is that the formula of the acrylic adhesive is different, see Table 2. The rest is the same as Example 1.

[0056] The above acrylic adhesive was uniformly coated by a coater to form a 20-um adhesive layer on a 100-um PET substrate, then a release film was covered on the adhesive-coated surface, and finally the roll was wound for use, to obtain an acrylic pressure-sensitive adhesive tape.

[0057] Table 2 Formula table of acrylic adhesive prepared in Comparative Examples 1-4 (the unit of each component in the table is g, such as ethyl acrylate 10, which means 10 g of ethyl acrylate)

[0058] Test Example: The acrylic adhesives and acrylic pressure-sensitive adhesive tapes prepared in Examples 1-6 and Comparative Examples 1-4 were tested for the following properties, and the test results are shown in Table 3: I. The glass transition temperature of the acrylic adhesive was tested according to the differential scanning calorimeter (DSC), and the DSC curve is shown in Figure 1 and Figure 2 The test standard is GB / T 19466.2-2004 "Plastics-Differential Scanning Calorimetry (DSC)-Part 2: Determination of Glass Transition Temperature"; II. The UV pre-peeling force was tested according to GB / T 2792 "180° Peel Strength Test Method for Pressure-Sensitive Adhesive Tape"; III. The UV post-peeling force was tested according to GB / T 2792 "180° Peel Strength Test Method for Pressure-Sensitive Adhesive Tape"; IV. The water resistance was tested according to GB / T 2792 "180° Peel Strength Test Method for Pressure-Sensitive Adhesive Tape", and the water resistance peeling force after the pressure-sensitive adhesive tape was soaked in water for 8 h at room temperature and normal pressure was used to judge; V. Acid resistance test The prepared acrylic ester pressure-sensitive adhesive tape was attached to a wafer, and then the wafer was soaked in 50% hydrofluoric acid (HF) for 1 h. After the wafer was taken out, whether bubbles or peeling appeared on the wafer-adhesive joint surface, whether the adhesive tape swelled, dissolved or discolored, and whether the wafer covered by the adhesive tape was corroded were observed. After the adhesive tape was removed, whether the wafer covered by the adhesive tape had residual adhesive or was corroded was observed. VI. Alkali resistance test The prepared acrylic ester pressure-sensitive adhesive tape was attached to a wafer, and then the wafer was soaked in 50% ammonia solution for 1 h. After the wafer was taken out, whether bubbles or peeling appeared on the wafer-adhesive joint surface, whether the adhesive tape swelled, dissolved or discolored, and whether the wafer covered by the adhesive tape was corroded were observed. After the adhesive tape was removed, whether the wafer covered by the adhesive tape had residual adhesive or was corroded was observed. VII. Residual adhesive test The prepared acrylic ester pressure-sensitive adhesive tape was attached to a wafer, and then the wafer was soaked in 50% ammonia solution for 1 h. After the wafer was taken out, whether bubbles or peeling appeared on the wafer-adhesive joint surface, whether the adhesive tape swelled, dissolved or discolored, and whether the wafer covered by the adhesive tape was corroded were observed. After the adhesive tape was removed, whether the wafer covered by the adhesive tape had residual adhesive or was corroded was observed.

[0059] Table 3. Performance test results of acrylic ester adhesives and acrylic ester pressure-sensitive adhesive tapes prepared in Examples 1-6 and Comparative Examples 1-4

[0060] From the data in Table 3, Figure 1 and Figure 2 it can be seen that the addition of PBO fibers and silane coupling agent at the same time increases the glass transition temperature of the acrylic ester adhesive and enhances the acid and alkali resistance. At the same time, the addition of PBO fibers and silane coupling agent increases the water resistance of the acrylic ester pressure-sensitive adhesive tape, so that the peel strength after 8 h of water immersion is still very close to the peel strength before UV, and does not affect the bonding performance. Moreover, when the pressure-sensitive adhesive tape has good water resistance, the water resistance peel strength value is higher than the peel strength before UV due to the longer attachment time.

[0061] In Comparative Example 2 and Comparative Example 4, PBO fibers were added to the acrylic resin, but no silane coupling agent was added. In this case, the PBO fibers were difficult to be uniformly mixed with the acrylic resin due to poor compatibility, two glass transition temperatures appeared in the resin system, the adhesive surface roughness increased, and the pressure-sensitive adhesive tape was difficult to be attached flat to the adherend, resulting in abnormal peel before and after UV. At the same time, the uneven mixing of PBO fibers and acrylic resin cannot improve the acid and alkali resistance of the adhesive tape.

[0062] As shown in Figures 3-6 Comparative Examples 1-3, the acrylic pressure-sensitive adhesive tapes prepared in the examples were attached to wafers, and after soaking in acid and alkali solutions, the pressure-sensitive adhesive tapes lost protection and the wafers were corroded. Figure 3 In Comparative Example 1, bubbles and acid penetration appeared on the wafer (without removing the adhesive tape). Figure 4 In Comparative Example 2, wafer (without removing the adhesive tape) appeared with edge lifting + bubbles + acid penetration. Figure 5 In Comparative Example 3, bubbles appeared on the wafer (without removing the adhesive tape). Figure 6The wafer of Comparative Example 3 (after stripping) showed corrosion (in the orange circle).

Claims

1. A method for preparing an acid and alkali resistant acrylic adhesive, characterized in that: The following steps are involved: Step S1, mixing 30-60 parts by weight of an acrylate soft monomer, 10-30 parts by weight of an acrylate hard monomer, 2-10 parts by weight of an acrylate functional monomer, 0.01-0.5 parts by weight of an initiator of Group A, and a first solvent of Group A to obtain a monomer mixed solution; Step S2, after heating under an inert atmosphere, adding 0.01 to 0.5 parts by weight of the initiator of group B, and keeping the temperature to react to obtain an acrylic resin precursor; Step S3, adding the first solvent of group B to dilute to obtain acrylic resin; Step S4: adding 0.1 to 2 parts by weight of a curing agent and mixing to obtain an acrylate adhesive precursor; Step S5: adding 1 to 10 parts of polybenzoxazole fiber, 1 to 10 parts of silane coupling agent, and a second solvent in parts by weight, and uniformly dispersing them to obtain an acid- and alkali-resistant acrylic adhesive.

2. The method for preparing the acid and alkali resistant acrylic adhesive according to claim 1, wherein: Include at least one of the following technical features: (1) In step S2, the inert atmosphere is one or a combination of nitrogen, argon, helium, neon, and krypton; (2) In step S2, the temperature is raised to 75°C to 85°C; (3) The heat preservation reaction time in step S2 is 3 to 4 hours; (4) In step S3, the first solvent of group B is added for dilution to obtain an acrylic resin with a solid content of 30% to 50%.

3. The method for preparing the acid and alkali resistant acrylic adhesive according to claim 1, wherein: In step S5, the polybenzoxazole fiber is surface pretreated to introduce hydroxyl groups.

4. The method for preparing the acid and alkali resistant acrylic adhesive according to claim 1, wherein: Include at least one of the following technical features: (1) The acrylic acid ester soft monomer in step S1 is one or more of ethyl acrylate, n-butyl acrylate, isooctyl acrylate, and lauryl methacrylate; (2) In step S1, the acrylic acid ester hard monomer is one or more of methyl acrylate, methyl methacrylate, styrene, vinyl acetate, and cyclohexyl acrylate; (3) In step S1, the acrylate functional monomer is one or more of 2-hydroxyethyl methacrylate, glycidyl methacrylate, isobornyl acrylate, acrylic acid, and itaconic acid.

5. The method for preparing the acid and alkali resistant acrylic adhesive according to claim 1, wherein: Include at least one of the following technical features: (1) In step S1, the initiator in group A is one or more of dibenzoyl peroxide, azobisisobutyronitrile, and V-601; (2) In step S2, the initiator of group B is one or more of dibenzoyl peroxide, azobisisobutyronitrile, and V-601; (3) In step S1, the first solvent of group A is one or more of toluene, ethyl acetate, acetone, and butyl acetate; (4) In step S3, the first solvent of group B is one or more of toluene, ethyl acetate, acetone, and butyl acetate.

6. The method for preparing the acid and alkali resistant acrylic adhesive according to claim 1, wherein: The curing agent in step S4 is one or more of toluene diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, 4,4-dicyclohexylmethane diisocyanate, and p-toluenesulfonyl isocyanate.

7. The method for preparing the acid and alkali resistant acrylic adhesive according to claim 1, wherein: Include at least one of the following technical features: (1) The silane coupling agent in step S5 is one or more of γ-aminopropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, and γ-mercaptopropyltriethoxysilane; (2) In step S5, the second solvent is one or more of ethanol, isopropanol, ethylene glycol, and glycerol.

8. The acid and alkali resistant acrylate adhesive prepared by the method for preparing the acid and alkali resistant acrylate adhesive according to any one of claims 1 to 7.

9. A method for preparing an acid- and alkali-resistant acrylic pressure-sensitive adhesive tape, using the acid- and alkali-resistant acrylic adhesive according to claim 8, characterized in that: The acid and alkali resistant acrylic adhesive is evenly coated on a substrate to obtain an acid and alkali resistant acrylic pressure-sensitive adhesive tape.

10. The acid and alkali resistant acrylate pressure-sensitive adhesive tape prepared by the method for preparing the acid and alkali resistant acrylate pressure-sensitive adhesive tape according to claim 9.

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