JP5555578B2 - Adhesive composition and adhesive tape - Google Patents

Description

The present invention has a high initial adhesive force and can firmly fix the adherend, and can be easily peeled off by irradiation with light even after a high temperature processing process of 200 ° C. or higher. The present invention relates to a pressure-sensitive adhesive composition and a pressure-sensitive adhesive tape using the pressure-sensitive adhesive composition.

A pressure-sensitive adhesive composition containing a pressure-sensitive adhesive component is widely used for a binder such as an adhesive, a sealing agent, a paint, and a coating agent, and a pressure-sensitive adhesive such as a pressure-sensitive adhesive tape or a self-supporting tape.
The performance required for these pressure-sensitive adhesive compositions varies depending on the application, but depending on the application, it may exhibit adhesiveness only for the required period, but may be required to be easily removed thereafter.

For example, in a semiconductor chip manufacturing process, a thick film wafer cut from a high-purity silicon single crystal or the like is polished to a predetermined thickness to form a thin film wafer, and the thick film wafer is bonded to a support plate. It has been proposed to work efficiently by reinforcing. An adhesive tape called a dicing tape is also used when dicing a thin film wafer ground to a predetermined thickness into individual semiconductor chips. The pressure-sensitive adhesive composition used in such a semiconductor manufacturing process can be firmly bonded during the process, and can be peeled without damaging the thin film wafer or semiconductor chip obtained after the process is finished (hereinafter, It is also called “high adhesion easy peeling”).

As a next-generation technology, a three-dimensional stacking technology using a TSV (Through Si via) that has been dramatically improved in performance by stacking a plurality of semiconductor chips has attracted attention. TSV can increase the density of semiconductor mounting, has an extremely fast access speed, and is excellent in releasing heat generated during use.
In manufacturing such a TSV, it is necessary to perform a high-temperature processing process of 200 ° C. or higher, such as bumping a thin film wafer obtained by grinding, bump formation on the back surface, or reflow during three-dimensional lamination. It becomes. Therefore, the pressure-sensitive adhesive composition used in the TSV manufacturing process is required to have heat resistance capable of maintaining adhesiveness even in a high temperature environment of 200 ° C. or higher, in addition to high adhesion easy peeling.

As a pressure-sensitive adhesive composition that achieves high adhesion and easy peeling, PTL 1 discloses a pressure-sensitive adhesive tape that uses a photo-curable pressure-sensitive adhesive that is cured by irradiation with light such as ultraviolet rays to reduce its adhesive strength. . It is said that such an adhesive tape can reliably fix the semiconductor during the processing step and can be easily peeled off by irradiating ultraviolet rays or the like. However, the pressure-sensitive adhesive tape described in Patent Document 1 has insufficient reduction in adhesive strength after irradiation with ultraviolet rays and the like, and it has been difficult to peel the film without damaging the thin film wafer, the semiconductor chip, or the like.

Patent Document 2 discloses a heat-peelable pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer containing thermally expandable microspheres. When the heat-peelable pressure-sensitive adhesive sheet of Patent Document 2 is heated to a certain temperature or more, the thermally expandable microspheres expand, the entire pressure-sensitive adhesive layer is foamed and irregularities are formed on the surface, and the adhesion area with the adherend is reduced. Therefore, the adherend can be easily peeled off. However, in the heat-peelable pressure-sensitive adhesive sheet described in Patent Document 2, the heat-expandable microspheres are expanded by heating, and fine irregularities are generated on the pressure-sensitive adhesive surface. The surface that adheres to the adherend due to this shape change develops stress that peels off the adhesive layer from the adherend during the expansion process, and the peeling progresses, but the fine irregularities become point adherence to the adherend. Since the adhesive force remains, it is difficult to peel the thin film wafer or the semiconductor chip without damaging them. In addition, there is also a problem that glue remains on the surface of the peeled adherend. Furthermore, even when heat-expandable microspheres having relatively high heat resistance are used, they have only heat resistance of about 130 ° C. and are difficult to use in the TSV manufacturing process.

Patent Document 3 describes a double-sided pressure-sensitive adhesive tape having an adhesive layer containing a gas generating agent that generates a gas by stimulation with an azo compound or the like. When the double-sided pressure-sensitive adhesive tape of Patent Document 3 is stimulated, gas generated from the gas generating agent is released to the interface between the surface of the tape and the adherend, and at least a part of the adherend is peeled off by the pressure. If the double-sided adhesive tape of patent document 3 is used, it can peel, without damaging a thin film wafer, a semiconductor chip, etc., and without the adhesive residue. However, the double-sided pressure-sensitive adhesive tape of Patent Document 3 may generate gas from an azo compound during a high-temperature process, which is problematic in terms of heat resistance and difficult to use in a TSV manufacturing process.

At present, in the TSV manufacturing process, adhesion is performed using an adhesive containing light absorber fine particles such as carbon black, and decomposition / separation is performed using laser-induced heat. (Non-Patent Document 1). However, in order to use the technique of Non-Patent Document 1, in addition to the facility problem that a laser irradiation device is required, fine particle powder is scattered due to decomposition of the adhesive by laser irradiation, and the production environment There was a problem of lowering the cleanliness.

JP-A-5-32946 JP-A-11-166164 JP 2003-231872 A

“Adhesion Technology” Vol. No. 28 1 (2008) No. 90 28

The present invention has a high initial adhesive force and can firmly fix the adherend, and can be easily peeled off by irradiation with light even after a high temperature processing process of 200 ° C. or higher. It aims at providing the adhesive composition which can be used, and the adhesive tape using this adhesive composition.

The present invention is a pressure-sensitive adhesive composition comprising a pressure-sensitive adhesive component and a tetrazole compound represented by the following general formula (1), general formula (2) or general formula (3), wherein the pressure-sensitive adhesive component is: The pressure-sensitive adhesive composition is a (meth) acrylic copolymer obtained by copolymerizing a monomer mixture containing a monomer having a basic functional group and another (meth) acrylic monomer.

In formulas (1) to (3), R ¹ and R ² represent hydrogen, an alkyl group having 1 to 7 carbon atoms, an alkylene group, a phenyl group, a mercapto group, a hydroxyl group, or an amino group.
The present invention is described in detail below.

The present inventor has shown that the tetrazole compounds represented by the above general formulas (1) to (3) generate gas (nitrogen gas) by irradiating light such as ultraviolet rays, and decompose at a high temperature of about 200 ° C. It has been found that it has high heat resistance. Therefore, a pressure-sensitive adhesive composition using a tetrazole compound and a pressure-sensitive adhesive component has high adhesive strength, but can be easily peeled off by irradiating light such as ultraviolet rays, and can be used in a TSV manufacturing process. It was expected to be as heat resistant as possible. However, in practice, the pressure-sensitive adhesive composition in which the tetrazole compound and the pressure-sensitive adhesive component are used together is inferior in adhesive strength, cannot be uniformly peeled during peeling, or the surface of the adherend is contaminated. There was a problem of getting stuck.

As a result of intensive studies, the present inventor has found that the problem of the pressure-sensitive adhesive composition containing the tetrazole compound is due to the low affinity between the tetrazole compound and the pressure-sensitive adhesive component. That is, the tetrazole compound has a low affinity with a general pressure-sensitive adhesive component, and could not be sufficiently dispersed in the pressure-sensitive adhesive component, resulting in inferior adhesive strength or uniform peeling during peeling. It was thought that it was not possible or caused the problem that the surface of the adherend was contaminated.
As a result of further intensive studies, the present inventor has obtained a tetrazole compound by using a specific (meth) acrylic copolymer obtained by copolymerizing a monomer mixture containing a monomer having a basic functional group as an adhesive component. Can be dispersed sufficiently uniformly, exhibit high initial adhesive strength, and can be easily peeled off by irradiation with light even after a high temperature processing process of 200 ° C. or higher. The inventors have found that a pressure-sensitive adhesive composition that does not contaminate the adherend can be obtained, and have completed the present invention.

The pressure-sensitive adhesive composition of the present invention contains a pressure-sensitive adhesive component.
The pressure-sensitive adhesive component is a (meth) acrylic copolymer (hereinafter simply referred to as “(meth) acrylic copolymer) obtained by copolymerizing a monomer mixture containing a monomer having a basic functional group and another (meth) acrylic monomer. It is also referred to as “) acrylic copolymer”. By having the component derived from the monomer which has a basic functional group, the said (meth) acrylic-type copolymer is excellent in affinity with the said tetrazole compound, and can disperse | distribute the said tetrazole compound uniformly.

The monomer having a basic functional group has a basic functional group such as a primary, secondary, tertiary amino group, or a functional group containing an N-containing heterocycle such as pyridine, pyrimidine, pyrazine, etc. ) Acrylic monomer.
Specific examples of the (meth) acrylic monomer having a basic functional group include dimethylaminoethyl acrylate, diethylaminoethyl acrylate, dibutylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, dibutylaminoethyl methacrylate, dimethylamino. Alkylamino (meth) acrylates such as propyl acrylate, diethylaminopropyl acrylate, dimethylaminopropyl methacrylate, t-butylaminoethyl acrylate, t-butylaminoethyl methacrylate, N- (dimethylaminoethyl) acrylamide, N- (diethylaminoethyl) ) Acrylamide, N- (dibutylaminoethyl) acrylamide, N- (dimethylaminoethyl) Tacrylamide, N- (diethylaminoethyl) methacrylamide, N- (dibutylaminoethyl) methacrylamide, N- (dimethylaminopropyl) acrylamide, N- (diethylaminopropyl) acrylamide, N- (dimethylaminopropyl) methacrylamide, t- N- (alkylaminoalkyl) (meth) acrylamides such as butylaminoethylacrylamide and t-butylaminoethylmethacrylamide, N, N-dimethylacrylamide, N, N-diethylacrylamide, N, N-dibutylacrylamide, N N, N-alkyl such as N, N-dimethylmethacrylamide, N, N-diethylmethacrylamide, N, N-dibutylmethacrylamide, Nt-butylacrylamide, Nt-butylmethacrylamide Meth) and acrylamides such as acrylamide and the like. These (meth) acrylic monomers having a basic functional group may be used alone or in combination of two or more. Among them, those that can be supplied industrially and are safe for use are suitable.

The minimum with preferable content of the monomer which has the said basic functional group in the said monomer mixture is 1 weight%, and a preferable upper limit is 50 weight%. When the content of the monomer having a basic functional group is less than 1% by weight, the tetrazole compound may not be sufficiently dispersed. When the content exceeds 50% by weight, the resulting (meth) acrylic copolymer A glass transition temperature becomes high and the adhesiveness of an adhesive composition may be inadequate. A more preferable lower limit of the amount of the monomer having a basic functional group is 5% by weight, and a more preferable upper limit is 30% by weight.

The other (meth) acrylic monomers are not particularly limited, but when a (meth) acrylic acid alkyl ester monomer having an alkyl group having 2 to 18 carbon atoms is used, the resulting (meth) acrylic monomer is used. It is preferable because the polymer can exhibit high adhesive force at room temperature of about 25 ° C.

The pressure-sensitive adhesive component may be curable. When the pressure-sensitive adhesive component is a curable adhesive, peeling occurs in the peeling mechanism described in Patent Document 3 by irradiating the pressure-sensitive adhesive composition of the present invention with light. That is, by emitting light, a gas is generated from the tetrazole compounds represented by the general formulas (1) to (3), and the generated gas is released from the cured adhesive component to the interface with the adherend. The pressure causes at least a part of the adherend to peel off.

The method of making the pressure-sensitive adhesive component a curable type uses, for example, a monomer having a functional group in the molecule (hereinafter, also referred to as “functional group-containing monomer”) as the other (meth) acrylic monomer ( A meth) acrylic copolymer (hereinafter also referred to as “functional group-containing (meth) acrylic copolymer”) is synthesized, and a functional group that reacts with the functional group in the molecule and a radical polymerizable unsaturated bond. And a compound obtained by reacting with a compound having a functional group (hereinafter referred to as a functional group-containing unsaturated compound) as a pressure-sensitive adhesive component.

The functional group-containing (meth) acrylic copolymer has a (meth) acrylic acid alkyl ester monomer having an alkyl group in the range of 2 to 18 carbon atoms as a main monomer in order to exhibit adhesiveness at room temperature, This can be obtained by copolymerizing the above-mentioned monomer having a basic functional group, a functional group-containing monomer, and, if necessary, another modifying monomer copolymerizable therewith by a conventional method.

Examples of the functional group-containing monomers include carboxyl group-containing monomers such as acrylic acid and methacrylic acid, hydroxyl group-containing monomers such as hydroxyethyl acrylate and hydroxyethyl methacrylate, and epoxy groups such as glycidyl acrylate and glycidyl methacrylate. Examples thereof include monomers containing monomers and isocyanate group-containing monomers such as isocyanate ethyl acrylate and isocyanate ethyl methacrylate.

Examples of other modifying monomers that can be copolymerized include various monomers used in general (meth) acrylic polymers such as vinyl acetate, acrylonitrile, and styrene.

The functional group-containing unsaturated compound reacted with the functional group-containing (meth) acrylic copolymer is the same as the functional group-containing monomer described above according to the functional group of the functional group-containing (meth) acrylic copolymer. Can be used. For example, when the functional group of the functional group-containing (meth) acrylic copolymer is a carboxyl group, an epoxy group-containing monomer or an isocyanate group-containing monomer is used. When the functional group is a hydroxyl group, an isocyanate group-containing monomer is used. When the functional group is an epoxy group, a carboxyl group-containing monomer or an amide group-containing monomer such as acrylamide is used.

When the pressure-sensitive adhesive component is curable, it is preferable to use a photopolymerization initiator or a thermal polymerization initiator in combination.
Examples of the photopolymerization initiator include those activated by irradiation with light having a wavelength of 250 to 800 nm. Examples of such a photopolymerization initiator include acetophenone derivative compounds such as methoxyacetophenone, Benzoin ether compounds such as benzoin propyl ether and benzoin isobutyl ether, ketal derivative compounds such as benzyldimethyl ketal and acetophenone diethyl ketal, phosphine oxide derivative compounds, bis (η5-cyclopentadienyl) titanocene derivative compounds, Benzophenone, Michler's ketone, chlorothioxanthone, todecylthioxanthone, dimethylthioxanthone, diethylthioxanthone, α-hydroxycyclohexyl phenyl ketone, 2-hydroxymethylphenyl group Examples include photo radical polymerization initiators such as lopan. These photoinitiators may be used independently and 2 or more types may be used together.

Examples of the thermal polymerization initiator include those that decompose by heat and generate active radicals that initiate polymerization and curing, such as dicumyl peroxide, di-t-butyl peroxide, and t-butyl peroxybenzoale. , T-butyl hydroperoxide, benzoyl peroxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, paramentane hydroperoxide, di-t-butyl peroxide and the like.
However, in order for the pressure-sensitive adhesive composition of the present invention to exhibit high heat resistance, it is preferable to use a thermal polymerization initiator having a thermal decomposition temperature of 200 ° C. or higher as the thermal polymerization initiator. Examples of the thermal polymerization initiator having a high thermal decomposition temperature include cumene hydroperoxide, paramentane hydroperoxide, di-t-butyl peroxide, and the like.
Although it does not specifically limit as what is marketed among these thermal polymerization initiators, For example, perbutyl D, perbutyl H, perbutyl P, perpenta H (all are the NOF Corporation make) etc. are suitable. These thermal polymerization initiators may be used independently and 2 or more types may be used together.

When the pressure-sensitive adhesive component is curable, it is preferable to further contain a radical polymerizable polyfunctional oligomer or monomer. By containing a radically polymerizable polyfunctional oligomer or monomer, photocurability and thermosetting are improved.
The polyfunctional oligomer or monomer preferably has a molecular weight of 10,000 or less, and more preferably has a molecular weight of 5000 or less so that the three-dimensional network of the pressure-sensitive adhesive layer can be efficiently formed by heating or light irradiation. And the number of radically polymerizable unsaturated bonds in the molecule is 2-20.

The polyfunctional oligomer or monomer is, for example, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate or the same methacrylate as described above. And the like. Other examples include 1,4-butylene glycol diacrylate, 1,6-hexanediol diacrylate, polyethylene glycol diacrylate, commercially available oligoester acrylate, and methacrylates similar to those described above. These polyfunctional oligomers or monomers may be used alone or in combination of two or more.

The minimum with a preferable weight average molecular weight of the said (meth) acrylic-type copolymer is 50,000, and a preferable upper limit is 800,000. When the weight average molecular weight of the (meth) acrylic copolymer is less than 50,000, the heat resistance may be lowered, and when it exceeds 800,000, the viscosity becomes too high and the operability may be deteriorated. The minimum with a more preferable weight average molecular weight of the said (meth) acrylic-type copolymer is 200,000, and a more preferable upper limit is 700,000.
The weight average molecular weight of the (meth) acrylic copolymer means a value measured by gel permeation chromatography analysis.

The pressure-sensitive adhesive composition of the present invention contains a tetrazole compound represented by the above general formulas (1) to (3). The tetrazole compounds represented by the above general formulas (1) to (3) generate a gas (nitrogen gas) by irradiating light such as ultraviolet rays, and have high heat resistance that does not decompose even at a high temperature of about 200 ° C. Have.
In the general formulas (1) to (3), R ¹ and R ² represent hydrogen, an alkyl group having 1 to 7 carbon atoms, an alkylene group, a phenyl group, a mercapto group, a hydroxyl group, or an amino group. R ¹ and R ² may be the same or different.

Although the tetrazole compound represented by the general formula (1) is not particularly limited, specifically, for example, 1H-tetrazole, 5-phenyl-1H-tetrazole, 5,5-azobis-1H-tetrazole, 5-amino- 1H-tetrazole, 5-methyl-1H-tetrazole, 1-methyl-5-mercapto-1H-tetrazole, 1-methyl-5-ethyl-1H-tetrazole, 1- (dimethylaminoethyl) -5-mercapto-1H- Examples include tetrazole, 1H-5hydroxy-tetrazole, 1methyl-5ethyltetrazole, 1propyl-5methyl-tetrazole, 1phenyl-5hydroxy-tetrazole, 1phenyl-5mercapto-tetrazole and the like.

The tetrazole compound represented by the general formula (2) is not particularly limited, and specific examples include 5,5'-bistetrazole and 5,5'-bistetrazole diammonium salt.

The tetrazole compound represented by the general formula (3) is not particularly limited, and specific examples include 5,5'-azobistetrazole and 5,5'-azobistetrazole aminoguanidine.

The content of the tetrazole compound represented by the general formulas (1) to (3) is preferably 1 part by weight with respect to 100 parts by weight of the pressure-sensitive adhesive component, and 40 parts by weight with a preferable upper limit. When the content of the tetrazole compound represented by the general formulas (1) to (3) is less than 1 part by weight, generation of nitrogen gas due to light irradiation is reduced and sufficient peeling may not be performed. If it exceeds 40 parts by weight, it may be difficult to uniformly disperse in the pressure-sensitive adhesive component, the initial adhesive strength may be reduced, uniform peeling may not be achieved during peeling, and the adherend may be contaminated. is there. The minimum with more preferable content of the tetrazole compound represented by the said General Formula (1)-(3) is 3 weight part, and a more preferable upper limit is 20 weight part.

The pressure-sensitive adhesive composition of the present invention may contain a photosensitizer.
Since the photosensitizer has an effect of amplifying light stimulation to the tetrazole compound represented by the general formulas (1) to (3) or a salt thereof, gas is released by irradiation with less light. be able to. In addition, gas can be emitted by light in a wider wavelength region.

The photosensitizer is not particularly limited as long as it has excellent heat resistance.
Examples of the photosensitizer excellent in heat resistance include polycyclic aromatic compounds having at least one alkoxy group. Among these, a substituted alkoxy polycyclic aromatic compound having an alkoxy group partially substituted with a glycidyl group or a hydroxyl group is preferable. These photosensitizers have high resistance to sublimation and can be used at high temperatures. Moreover, when a part of the alkoxy group is substituted with a glycidyl group or a hydroxyl group, the solubility in the pressure-sensitive adhesive component is increased, and bleeding out can be prevented.

The polycyclic aromatic compound is preferably an anthracene derivative. The alkoxy group preferably has 1 to 18 carbon atoms, and more preferably has 1 to 8 carbon atoms.

Examples of the polycyclic aromatic compound having at least one alkoxy group include 9,10-dimethoxyanthracene, 2-ethyl-9,10-dimethoxyanthracene, 2-tbutyl-9,10-dimethoxyanthracene, 2, 3-dimethyl-9,10-dimethoxyanthracene, 9-methoxy-10-methylanthracene, 9,10-diethoxyanthracene, 2-ethyl-9,10-diethoxyanthracene, 2-tbutyl-9,10-di Ethoxyanthracene, 2,3-dimethyl-9,10-diethoxyanthracene, 9-ethoxy-10-methylanthracene, 9,10-dipropoxyanthracene, 2-ethyl-9,10-dipropoxyanthracene, 2-tbutyl -9,10-dipropoxyanthracene, 2,3-dimethyl-9, 0-dipropoxyanthracene, 9-isopropoxy-10-methylanthracene, 9,10-dibutoxyanthracene, 9,10-dibenzyloxyanthracene, 2-ethyl-9,10-dibenzyloxyanthracene, 2-tbutyl -9,10-dibenzyloxyanthracene, 2,3-dimethyl-9,10-dibenzyloxyanthracene, 9-benzyloxy-10-methylanthracene, 9,10-di-α-methylbenzyloxyanthracene, 2- Ethyl-9,10-di-α-methylbenzyloxyanthracene, 2-tbutyl-9,10-di-α-methylbenzyloxyanthracene, 2,3-dimethyl-9,10-di-α-methylbenzyloxy Anthracene, 9- (α-methylbenzyloxy) -10-methylanthracase , 9,10-di (2-hydroxyethoxy) anthracene, and the like anthracene derivative such as 2-ethyl-9,10-di (2-carboxyethoxy) anthracene.

The substituted alkoxy polycyclic aromatic compound having an alkoxy group partially substituted with a glycidyl group or a hydroxyl group is, for example, 9,10-di (glycidyloxy) anthracene, 2-ethyl-9,10-di (glycidyloxy). ) Anthracene, 2-tbutyl-9,10-di (glycidyloxy) anthracene, 2,3-dimethyl-9,10-di (glycidyloxy) anthracene, 9- (glycidyloxy) -10-methylanthracene, 9, 10-di (2-vinyloxyethoxy) anthracene, 2-ethyl-9,10-di (2-vinyloxyethoxy) anthracene, 2-tbutyl-9,10-di (2-vinyloxyethoxy) anthracene, 2 , 3-Dimethyl-9,10-di (2-vinyloxyethoxy) anthracene, 9- (2-vinyloxy) Ethoxy) -10-methylanthracene, 9,10-di (3-methyl-3-oxetanylmethoxy) anthracene, 2-ethyl-9,10-di (3-methyl-3-oxetanylmemethoxy) anthracene, 2-t Butyl-9,10-di (3-methyl-3-oxetanylmemethoxy) anthracene, 2,3-dimethyl-9,10-di (3-methyl-3-oxetanylmemethoxy) anthracene, 9- (3-methyl -3-oxetanylmemethoxy) -10-methylanthracene, 9,10-di (p-epoxyphenylmethoxy) anthracene, 2-ethyl-9,10-di (p-epoxyphenylmethoxy) anthracene, 2-tbutyl- 9,10-di (p-epoxyphenylmethoxy) anthracene, 2,3-dimethyl-9,10-di (p-ethylene) Xylphenylmethoxy) anthracene, 9- (p-epoxyphenylmethoxy) -10-methylanthracene, 9,10-di (p-vinylphenylmethoxy) anthracene, 2-ethyl-9,10-di (p-vinylphenylmethoxy) ) Anthracene, 2-tbutyl-9,1-di (p-vinylphenylmethoxy) anthracene, 2,3-dimethyl-9,10-di (p-vinylphenylmethoxy) anthracene, 9- (p-vinylphenylmethoxy) ) -10-methylanthracene, 9,10-di (2-hydroxyethoxy) anthracene, 9,10-di (2-hydroxypropoxy) anthracene, 9,10-di (2-hydroxybutoxy) anthracene, 9,10- Di (2-hydroxy-3-butoxypropoxy) anthracene, 9,10-di (2-Hydroxy-3- (2-ethylhexyloxy) propoxy) anthracene, 9,10-di (2-hydroxy-3-allyloxypropoxy) anthracene, 9,10-di (2-hydroxy-3-phenoxypropoxy) Anthracene, 9,10-di (2,3-dihydroxypropoxy) anthracene, etc. are mentioned.

The content of the photosensitizer is preferably 0.05 parts by weight and preferably 10 parts by weight with respect to 100 parts by weight of the pressure-sensitive adhesive component. When the content of the photosensitizer is less than 0.05 parts by weight, a sufficient sensitizing effect may not be obtained. When the content exceeds 10 parts by weight, the residue derived from the photosensitizer increases. , Sufficient peeling may not be performed. The minimum with more preferable content of the said photosensitizer is 0.1 weight part, and a more preferable upper limit is 5 weight part.

The pressure-sensitive adhesive composition of the present invention appropriately contains various polyfunctional compounds blended in general pressure-sensitive adhesives such as isocyanate compounds, melamine compounds, and epoxy compounds as needed for the purpose of adjusting the cohesive force as the pressure-sensitive adhesive. You may contain.
The pressure-sensitive adhesive composition of the present invention may contain known additives such as a plasticizer, a resin, a surfactant, a wax, and a fine particle filler.

While the pressure-sensitive adhesive composition of the present invention has high adhesive strength, it can be easily peeled off by light irradiation or heating. Moreover, since it is excellent also in heat resistance, it can be used for applications in which high-temperature treatment at 200 ° C. or higher, such as fixing a wafer to a support plate in the TSV manufacturing process, is performed.

The pressure-sensitive adhesive composition of the present invention can be used for various adhesive products.
Examples of the adhesive product include an adhesive, a pressure-sensitive adhesive, a paint, a coating agent, a sealing agent, and the like using the pressure-sensitive adhesive composition of the present invention as a binder resin, or the pressure-sensitive adhesive composition of the present invention as a pressure-sensitive adhesive. Examples of the adhesive tape include single-sided adhesive tape, double-sided adhesive tape, and non-support tape (self-supporting tape).

An adhesive tape having an adhesive layer made of the adhesive composition of the present invention on at least one surface of the substrate is also one aspect of the present invention.
The base material is, for example, a sheet made of a transparent resin such as acrylic, olefin, polycarbonate, vinyl chloride, ABS, polyethylene terephthalate (PET), nylon, urethane, polyimide, a sheet having a network structure, or a hole. Sheet.

According to the present invention, the adherend can be firmly fixed with a high initial adhesive force, and easily peeled off by irradiation with light even after a high temperature processing process of 200 ° C. or higher. An adhesive composition that can be used and an adhesive tape using the adhesive composition can be provided.

Hereinafter, embodiments of the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

Example 1
(1) Preparation of pressure-sensitive adhesive component A reactor equipped with a thermometer, a stirrer, and a cooling tube was prepared. In this reactor, 85 parts by weight of 2-ethylhexyl acrylate, 2.5 parts by weight of acrylic acid, 2-hydroxyethyl After adding 2.5 parts by weight of acrylate, 10 parts by weight of dimethylaminoethyl acrylate, 0.01 part by weight of lauryl mercaptan, and 180 parts by weight of ethyl acetate, the reactor was heated to start refluxing. Subsequently, 0.01 parts by weight of 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane was added as a polymerization initiator in the reactor, and polymerization was started under reflux. It was. Next, after 1 hour and 2 hours from the start of polymerization, 0.01 parts by weight of 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane was added, and the polymerization was started. 4 hours later, 0.05 part by weight of t-hexylperoxypivalate was added to continue the polymerization reaction. And 8 hours after the start of polymerization, an acrylic copolymer having a solid content of 55% by weight and a weight average molecular weight of 600,000 was obtained.

The resin solid content of 100 parts by weight of the ethyl acetate solution containing the acrylic copolymer thus obtained is reacted by adding 3.5 parts by weight of 2-isocyanatoethyl methacrylate, and further the resin of the ethyl acetate solution after the reaction. 0.1 parts by weight of photopolymerization initiator (Esacure One, manufactured by Nippon Shibel Hegner) and 2.5 parts by weight of polyisocyanate-based crosslinking agent (Coronate L45, manufactured by Nippon Polyurethane) were mixed and adhered to 100 parts by weight of solid content. An ethyl acetate solution of the agent component was prepared.

(2) Preparation of pressure-sensitive adhesive composition 20 parts by weight of 5-phenyl-1H-tetrazole (manufactured by Toyo Kasei Kogyo Co., Ltd.) as a photosensitizer with respect to 100 parts by weight of the resin solid content of the ethyl acetate solution of the pressure-sensitive adhesive component A pressure-sensitive adhesive composition was obtained by mixing 1 part by weight of 9,10-diglycidyloxyanthracene.

(3) Manufacture of pressure-sensitive adhesive tape The obtained pressure-sensitive adhesive composition has a dry film thickness of 30 μm on the corona-treated surface of a transparent polyethylene terephthalate film having a thickness of 50 μm with one side subjected to corona treatment. Coating was performed with a doctor knife, and the coating solution was dried by heating at 110 ° C. for 5 minutes. Thereafter, static curing was performed at 40 ° C. for 3 days to obtain an adhesive tape.

(Example 2)
Except that the monomer used in the preparation of the pressure-sensitive adhesive component was 94 parts by weight of 2-ethylhexyl acrylate, 2.5 parts by weight of acrylic acid, 2.5 parts by weight of 2-hydroxyethyl acrylate, and 1 part by weight of dimethylaminoethyl acrylate. In the same manner as in No. 1, an adhesive component, an adhesive composition and an adhesive tape were obtained.

(Example 3)
Except that the monomers used in the preparation of the pressure-sensitive adhesive component were 45 parts by weight of 2-ethylhexyl acrylate, 2.5 parts by weight of acrylic acid, 2.5 parts by weight of 2-hydroxyethyl acrylate, and 50 parts by weight of dimethylaminoethyl acrylate. In the same manner as in No. 1, an adhesive component, an adhesive composition and an adhesive tape were obtained.

(Example 4)
The monomer used in the preparation of the pressure-sensitive adhesive component was the same as in Example 1 except that 85 parts by weight of 2-ethylhexyl acrylate, 2.5 parts by weight of acrylic acid, 2.5 parts by weight of 2-hydroxyethyl acrylate, and 10 parts by weight of acrylamide were used. Thus, an adhesive component, an adhesive composition and an adhesive tape were obtained.

(Example 5)
Example 1 except that the monomers used in the preparation of the adhesive component were 85 parts by weight of 2-ethylhexyl acrylate, 2.5 parts by weight of acrylic acid, 2.5 parts by weight of 2-hydroxyethyl acrylate, and 10 parts by weight of diethyl acrylamide. Similarly, an adhesive component, an adhesive composition, and an adhesive tape were obtained.

(Example 6)
A pressure-sensitive adhesive component, a pressure-sensitive adhesive composition and a pressure-sensitive adhesive tape were obtained in the same manner as in Example 2 except that 1H-tetrazole was used instead of 5-phenyl-1H-tetrazole (manufactured by Toyo Kasei Kogyo Co., Ltd.).

(Example 7)
A pressure-sensitive adhesive component, a pressure-sensitive adhesive composition and a pressure-sensitive adhesive tape were obtained in the same manner as in Example 2 except that 1-phenyl-5 mercapto-tetrazole was used instead of 5-phenyl-1H-tetrazole (manufactured by Toyo Kasei Kogyo Co., Ltd.). Obtained.

(Comparative Example 1)
The adhesive used in the preparation of the adhesive component was the same as in Example 1 except that the monomer used was 95 parts by weight of 2-ethylhexyl acrylate, 2.5 parts by weight of acrylic acid, and 2.5 parts by weight of 2-hydroxyethyl acrylate. Ingredients, adhesive composition and adhesive tape were obtained.

(Comparative Example 2)
Instead of 20 parts by weight of 5-phenyl-1H-tetrazole (Toyo Kasei Kogyo Co., Ltd.), 20 parts by weight of 2,2′-azobis- (N-butyl-2-methylpropionamide), 9,10-diglycidyloxy A pressure-sensitive adhesive component, a pressure-sensitive adhesive composition, and a pressure-sensitive adhesive tape were obtained in the same manner as in Example 2 except that 3 parts by weight of diethylthioxanthone was blended in place of 1 part by weight of anthracene.

(Evaluation)
About the adhesive component, adhesive composition, and adhesive tape obtained by the Example and the comparative example, it evaluated by the following method.
The results are shown in Table 1.

(1) Evaluation of compatibility between adhesive component and tetrazole compound 20 parts by weight of 5-phenyl-1H-tetrazole (manufactured by Toyo Kasei Kogyo Co., Ltd.) with respect to 100 parts by weight of the adhesive component obtained in Examples and Comparative Examples Parts were mixed to prepare a mixture. The obtained mixture was dried in an oven at 110 ° C. for 20 minutes, and the dried state was visually observed. The compatibility after the drying was evaluated as “◯”, the cloudiness as “Δ”, and the tetrazole reprecipitated as “x” to evaluate the compatibility.

(2) Adhesiveness evaluation, peelability evaluation, contamination evaluation An adhesive tape cut into a circle having a diameter of 20 cm was attached to a silicon wafer having a diameter of 20 cm and a thickness of about 750 μm.
As an adhesive evaluation, when the adhesive tape was pulled in this state, it was “○” when it was not peeled at all, “△” when it was peeled relatively lightly, and “×” when it was peeled almost without resistance. evaluated.
Next, using an ultrahigh pressure mercury lamp from the glass plate side, irradiation with 365 nm ultraviolet rays was performed for 2 minutes while adjusting the illuminance so that the irradiation intensity on the surface of the glass plate was 40 mW / cm ² . As the peelability evaluation after UV irradiation, the case where the adhesive tape was pulled and could be peeled without any resistance was indicated as `` ○ '', the case where there was resistance but could be peeled as `` △ '', and the case where no peeling was possible. “×”.
Furthermore, the surface of the adherend after peeling was visually observed. As the evaluation of contamination after peeling, the case where the adherend was not contaminated was evaluated as “◯”, and the case where the contamination was observed was evaluated as “x”.

(3) Evaluation of heat resistance An adhesive tape cut into a circle having a diameter of 20 cm was attached to a silicon wafer having a diameter of 20 cm and a thickness of about 750 μm. The laminate was heated at 200 ° C. for 1 hour and then returned to room temperature.
About the laminated body after a heating, said adhesive evaluation, peelability evaluation, and pollution evaluation were performed.

According to the present invention, the adherend can be firmly fixed with a high initial adhesive force, and easily peeled off by irradiation with light even after a high temperature processing process of 200 ° C. or higher. An adhesive composition that can be used and an adhesive tape using the adhesive composition can be provided.

Claims (3)

A pressure-sensitive adhesive composition comprising a pressure-sensitive adhesive component and a tetrazole compound represented by the following general formula (1), general formula (2) or general formula (3),
The pressure-sensitive adhesive component is a (meth) acrylic copolymer obtained by copolymerizing a monomer mixture containing a monomer having a basic functional group and another (meth) acrylic monomer. Adhesive composition.

In formulas (1) to (3), R ¹ and R ² represent hydrogen, an alkyl group having 1 to 7 carbon atoms, an alkylene group, a phenyl group, a mercapto group, a hydroxyl group, or an amino group. The pressure-sensitive adhesive composition according to claim 1, wherein the content of the monomer having a basic functional group in the monomer mixture is 1 to 50% by weight. An adhesive tape comprising an adhesive layer made of the adhesive composition according to claim 1 or 2 on at least one surface of a substrate.