JP5941544B2 - Tetrazole compound or salt thereof, adhesive composition and adhesive tape - Google Patents

Description

The present invention relates to a tetrazole compound or a salt thereof excellent in heat resistance and excellent in reactivity to long-wavelength ultraviolet rays having a wavelength of 300 nm or more, an adhesive composition containing the tetrazole compound or a salt thereof, and an adhesive tape.

A tetrazole compound or a salt thereof generates a gas (nitrogen gas) when irradiated with light, and has a unique property of exhibiting high heat resistance that does not decompose even at a high temperature of about 200 ° C. In recent years, various products using such properties of tetrazole compounds have been studied. For example, Patent Document 1 describes an adhesive composition containing an adhesive component and a tetrazole compound represented by a specific general formula or a salt thereof.

Adhesive compositions containing an adhesive component are widely used for binders such as adhesives, sealing agents, paints and coating agents, and pressure-sensitive adhesives such as pressure-sensitive adhesive tapes and self-supporting tapes.
The performance required for these adhesive compositions varies depending on the application, but depending on the application, it may be required to exhibit adhesiveness only for the required time but to be easily peeled off 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 adhesive composition used in such a semiconductor manufacturing process is firmly bonded during the process, but can be peeled off without damaging the obtained thin film wafer, semiconductor chip, etc. 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 adhesive composition used in the TSV manufacturing process is required to have heat resistance capable of maintaining adhesion even at a high temperature of about 250 ° C. in addition to high adhesion and easy peeling.

In Patent Document 1, an adhesive composition containing a tetrazole compound or a salt thereof is disclosed as an adhesive composition that has high adhesive force but can be easily peeled off and is excellent in heat resistance. The tetrazole compound represented by a specific general formula or a salt thereof used in Patent Document 1 generates gas (nitrogen gas) when irradiated with light, but has high heat resistance that does not decompose even at a high temperature of about 200 ° C. Have An adhesive composition using these compounds and an adhesive component in combination has high adhesive strength and can be easily peeled off, and is excellent in heat resistance to such an extent that it can be used in a TSV manufacturing process. .

International Publication No. 2001/118506

The tetrazole compound represented by the specific general formula used in Patent Document 1 or a salt thereof generates gas (nitrogen gas) when irradiated with light, but has high heat resistance that does not decompose even at a high temperature of about 200 ° C. Have However, although these conventional tetrazole compounds are extremely excellent in terms of heat resistance, there are problems in terms of photoreactivity. In particular, conventional tetrazole compounds have low reactivity to long-wavelength ultraviolet rays having a wavelength of 300 nm or more, and even when irradiated with ultraviolet rays, a sufficient amount of gas (nitrogen gas) is not generated or even if generated, it is very long. There was a problem of requiring UV irradiation.

In view of the above situation, the present invention is a tetrazole compound or a salt thereof excellent in heat resistance and excellent in reactivity to a long wavelength ultraviolet ray having a wavelength of 300 nm or more, an adhesive composition containing the tetrazole compound or a salt thereof, and an adhesive tape The purpose is to provide.

A tetrazole compound having a molecular weight of 800 or less and having a structure in which the 5-position between two tetrazole structures is bonded to the main chain with a group having an aromatic ring or a salt thereof.
The present invention is described in detail below.

As a result of intensive studies, the present inventors have found that a tetrazole compound having a molecular weight of 800 or less and having a structure in which the 5-position between two tetrazole structures is bonded to the main chain by a group having an aromatic ring is And the present invention was completed by finding that it is excellent in reactivity and excellent in reactivity to long-wavelength ultraviolet rays having a wavelength of 300 nm or more. This is a group having an aromatic ring in the main chain having excellent photosensitivity and high rigidity between the tetrazole structures in addition to having a plurality of tetrazole structures substituted at the 5-position, which are excellent in gas generation. It is considered that heat resistance and photoreactivity can be achieved by combining them.
Here, the “structure bonded to the main chain with a group having an aromatic ring” means that the group having the aromatic ring is arranged on a chain directly connecting two tetrazole structures. To do.

In the tetrazole compound of the present invention or a salt thereof, the tetrazole structure arranged at both ends is specifically represented by any of the groups represented by the following formulas (1-1) to (1-3).

In the above formula, R is hydrogen, an alkyl group having 1 to 7 carbon atoms, an alkylene group, a phenyl group, a mercapto group, a hydroxyl group, an amino group, a carboxyl group, an epoxy group, an acrylic group, a methacryl group, a glycidyl group, a benzamide group, p-epoxyphenyl group, nitro group, acetaminophenyl group, carboxyphenyl group, aminophenyl group, hydroxyphenyl group, cyano group, methoxy group, ethoxy group, acetamide group, acetoxy group, sulfonic acid group, aldehyde group, acetyl group Or a silanol group.

In the tetrazole compound of the present invention or a salt thereof, examples of the group having an aromatic ring in the main chain connecting the tetrazole structures include groups having a phenyl skeleton, a naphthalene skeleton, an anthracene skeleton, and a phenanthrene skeleton. Examples include groups represented by the following formulas (2-1) to (2-68).

In the above formula, R and R ′ are hydrogen, an alkyl group having 1 to 7 carbon atoms, an alkylene group, a phenyl group, a mercapto group, a hydroxyl group, an amino group, a carboxyl group, an epoxy group, an acrylic group, a methacryl group, a glycidyl group, Benzamide group, p-epoxyphenyl group, nitro group, acetaminophenyl group, carboxyphenyl group, aminophenyl group, hydroxyphenyl group, cyano group, methoxy group, ethoxy group, acetamide group, acetoxy group, sulfonic acid group, aldehyde group Represents an acetyl group or a silanol group. X represents carbon, nitrogen, oxygen, phosphorus, silicon, or sulfur.

The group having an aromatic ring in the main chain may be used alone, or two or more kinds may be used in combination. That is, the tetrazole structures may be bonded to a plurality of the main chains with a group having an aromatic ring. When the tetrazole structure is bonded to a plurality of the main chains with a group having an aromatic ring, the groups having an aromatic ring to the main chain may be directly bonded to each other, or may be bonded with other groups. Also good.
Specific examples of the group that bonds between the groups having an aromatic ring in the main chain include groups represented by the following formulas (3-1) to (3-17). The group which bonds between the groups having an aromatic ring in the main chain may be used alone or in combination of two or more.

In the above formula, R and R ′ are hydrogen, an alkyl group having 1 to 7 carbon atoms, an alkylene group, a phenyl group, a mercapto group, a hydroxyl group, an amino group, a carboxyl group, an epoxy group, an acrylic group, a methacryl group, a glycidyl group, Benzamide group, p-epoxyphenyl group, nitro group, acetaminophenyl group, carboxyphenyl group, aminophenyl group, hydroxyphenyl group, cyano group, methoxy group, ethoxy group, acetamide group, acetoxy group, sulfonic acid group, aldehyde group Represents an acetyl group or a silanol group.

A salt of a tetrazole compound having a molecular weight of 800 or less and a structure in which the 5-position between two tetrazole structures is bonded to the main chain with a group having an aromatic ring is also included in the present invention. Since such a salt also has a skeleton derived from a tetrazole compound having a structure in which the 5-position between two tetrazole structures is bonded with a group having an aromatic ring in the main chain, it has high heat resistance and a wavelength of 300 nm or more. And reactivity to ultraviolet rays.
A salt of a tetrazole compound having a molecular weight of 800 or less and having a structure in which the 5-position between two tetrazole structures is bonded to the main chain with a group having an aromatic ring is not particularly limited, and examples thereof include sodium salts, potassium salts, Ammonium salts, zinc salts, copper salts, lithium salts, magnesium salts, calcium salts, cesium salts and the like can be mentioned.

Such a tetrazole compound salt contains a tetrazole compound having a molecular weight of 800 or less and a basic compound having a structure in which the 5-position of two tetrazole structures is bonded to the main chain by a group having an aromatic ring. It can be easily prepared without going through a complicated synthetic route only by mixing in.
The basic compound is not particularly limited, and examples thereof include amines, hydrazine compounds, quaternary ammonium hydroxide salts, and phosphine compounds.
The amine is not particularly limited, and any of primary amines, secondary amines, and tertiary amines can be used.

Among the tetrazole compounds or salts thereof of the present invention, tetrazole compounds having a smaller molecular weight are preferred. This is because when the same amount of tetrazole compound is blended when the molecular weight is small, the total amount of functional groups that generate gas increases, and as a result, the amount of gas generation increases. In addition, a tetrazole compound having a generally low molecular weight is simpler and easier to synthesize.

Among the tetrazole compounds or salts thereof according to the present invention, tetrazole compounds or salts thereof having a maximum molar extinction coefficient at a wavelength of 300 to 400 nm of 100 L / mol · cm or more are more preferable. A tetrazole compound or a salt thereof having a maximum molar extinction coefficient at a wavelength of 300 to 400 nm of 100 L / mol · cm or more is easy even when irradiated with a light source having a relatively small output such as ultraviolet light or white light. A gas (nitrogen gas) can be generated. In general, a mercury lamp often used as a UV light source emits light having a large energy in the vicinity of 310 nm. Therefore, the maximum value of the molar extinction coefficient at a wavelength of 305 to 400 nm is more than 100 L / mol · cm. preferable.

In the present specification, the molar extinction coefficient means that a dimethylformamide solution of a tetrazole compound having a concentration of about 3 to 5 × 10 ⁻³ mol / L is prepared using a spectrophotometer (for example, U-3000 manufactured by Hitachi, Ltd.). It means a value obtained by measuring an absorption spectrum in a wavelength range of 200 to 600 nm according to the following formula and calculating the following formula using the absorbance in the obtained absorption spectrum.
ε = A / c × d
In the formula, ε represents the molar extinction coefficient, A represents the absorbance, c represents the molar concentration, and d represents the cell thickness.
In the present specification, the maximum value of the molar extinction coefficient at a wavelength of 300 to 400 nm is 100 or more as long as the molar extinction coefficient at any wavelength between the wavelengths of 300 nm and 400 nm is 100 or more. The peak of the molar extinction coefficient does not need to exist between wavelengths of 300 nm to 400 nm.

Among the tetrazole compounds or salts thereof of the present invention, the weight residual ratio (hereinafter also simply referred to as “weight residual ratio”) when heated from 120 ° C. to 200 ° C. measured using a thermobalance is 85% or more. Tetrazole compounds are preferred because they are extremely excellent in heat resistance. The weight residual ratio is preferably 90% or more, more preferably 95% or more.

The weight residual rate is determined by, for example, weighing 5 to 10 mg of a tetrazole compound in an aluminum pan of a thermobalance (eg, TG / DTA6200 manufactured by SII), in an air atmosphere (flow rate 200 mL / min), and a rate of temperature increase of 5 ° C. / First, the temperature is raised from room temperature (30 ° C.) to 120 ° C. for 60 minutes under the condition of minutes. Subsequently, it can be obtained by measuring the weight reduction rate when the temperature is raised from 120 ° C. to 200 ° C. under the same temperature rise rate condition.
Here, “from 120 ° C.” is used to eliminate the influence of water adsorbed on the tetrazole compound.

Specific examples of the tetrazole compound or salt thereof of the present invention include tetrazole compounds represented by the following formulas (A) to (F) or salts thereof.

The method for producing the tetrazole compound of the present invention or a salt thereof is not particularly limited. For example, sodium azide is added to a molecule having a cyano group having a structure corresponding to the target tetrazole compound, and heated to heat the compound of the present invention. Examples thereof include a method for obtaining a tetrazole compound.

An adhesive composition containing an adhesive component and the tetrazole compound of the present invention or a salt thereof is also one aspect of the present invention.

The adhesive component is not particularly limited, and may contain either a non-curable adhesive or a curable adhesive.
When the adhesive component contains a non-curable adhesive, gas is generated from the tetrazole compound of the present invention or a salt thereof by irradiating the adhesive composition of the present invention with light, Due to the generated gas, the entire soft adhesive component is foamed and irregularities are formed on the surface, whereby a peeling stress is generated, and the adhesion area with the adherend is reduced and peeling occurs.

The non-curable adhesive is not particularly limited. For example, a rubber adhesive, an acrylic adhesive, a vinyl alkyl ether adhesive, a silicone adhesive, a polyester adhesive, a polyamide adhesive, and a urethane adhesive. Agents, styrene / diene block copolymer adhesives, and the like.

When the adhesive component contains a curable adhesive, gas is generated from the tetrazole compound of the present invention or a salt thereof by generating light by irradiating the adhesive composition of the present invention with light. The released gas is released from the cured adhesive component to the interface with the adherend, and at least a part of the adherend is peeled off by the pressure.
Especially, since reliable peeling can be performed without generating adhesive residue, it is preferable to contain a curable adhesive whose elastic modulus is increased by stimulation.

The curable adhesive is not particularly limited, and examples thereof include a photocurable adhesive and a thermosetting adhesive containing a polymerizable polymer as a main component and a photopolymerization initiator and a thermal polymerization initiator.
Such photo-curing adhesives and thermosetting adhesives are uniformly and rapidly polymerized and integrated by light irradiation or heating so that the elastic modulus is significantly increased by polymerization curing. Thus, the adhesive strength is greatly reduced. In addition, when a gas is generated from a tetrazole compound or a salt thereof in a hard cured product having an increased elastic modulus, most of the generated gas is released to the outside, and the released gas is transferred from the adherend to the adhesive adhesive surface. At least a part of the film is peeled off to reduce the adhesion.

The polymerizable polymer is prepared by, for example, previously synthesizing a (meth) acrylic polymer having a functional group in the molecule (hereinafter referred to as a functional group-containing (meth) acrylic polymer) and reacting with the functional group in the molecule. It can obtain by making it react with the compound (henceforth a functional group containing unsaturated compound) which has a functional group to perform and a radically polymerizable unsaturated bond.

The functional group-containing (meth) acrylic polymer is an acrylic having an alkyl group usually in the range of 2 to 18 as a polymer having adhesiveness at room temperature, as in the case of a general (meth) acrylic polymer. By copolymerizing an acid alkyl ester and / or methacrylic acid alkyl ester as a main monomer, a functional group-containing monomer, and, if necessary, another modifying monomer copolymerizable therewith by a conventional method It is obtained. The weight average molecular weight of the functional group-containing (meth) acrylic polymer is usually about 200,000 to 2,000,000.

Examples of the functional group-containing monomer 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 such as glycidyl acrylate and glycidyl methacrylate. Examples thereof include group-containing monomers, isocyanate group-containing monomers such as isocyanate ethyl acrylate and isocyanate ethyl methacrylate, and amino group-containing monomers such as aminoethyl acrylate and aminoethyl 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 to be reacted with the functional group-containing (meth) acrylic polymer is the same as the functional group-containing monomer described above according to the functional group of the functional group-containing (meth) acrylic polymer. it can. For example, when the functional group of the functional group-containing (meth) acrylic polymer is a carboxyl group, an epoxy group-containing monomer or an isocyanate group-containing monomer is used, and 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, and when the functional group is an amino group, an epoxy group-containing monomer is used.

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 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.

The photocurable adhesive and thermosetting adhesive preferably 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 content of the tetrazole compound of the present invention or a salt thereof in the adhesive composition of the present invention is preferably 5 parts by weight with respect to 100 parts by weight of the adhesive component, and 50 parts by weight with respect to the preferred upper limit. When the content of the tetrazole compound or a salt thereof of the present invention is within this range, sufficient nitrogen gas is generated when irradiation with a long wavelength ultraviolet ray having a wavelength of 300 mn or longer, and peeling can be performed. The adhesive strength of the composition is not impaired. The minimum with more preferable content of the tetrazole compound or its salt of this invention is 10 weight part, and a more preferable upper limit is 30 weight part.

The adhesive composition of the present invention may contain a photosensitizer.
Since the photosensitizer has an effect of amplifying light stimulation to the tetrazole compound of the present invention or a salt thereof, gas can be released by irradiation with less light. 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 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 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 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 pressure-sensitive adhesives. You may contain.
The 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 adhesive composition of the present invention has high adhesive strength, it can be easily peeled off by light irradiation or heating. In particular, even when a long wavelength ultraviolet ray having a wavelength of 300 nm or more is irradiated, gas can be generated quickly to perform peeling. 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 adhesive composition of the present invention can be used for various adhesive products.
As the adhesive product, for example, an adhesive, an adhesive, a paint, a coating agent, a sealing agent, or the like using the adhesive composition of the present invention as a binder resin, or the adhesive composition of the present invention as an 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 one surface of the substrate is also one aspect of the present invention.
The adhesive tape which has the adhesive layer which consists of an adhesive composition of this invention on both surfaces of a base material is also one of this invention.
The adhesive tape of the present invention is, for example, a back grinding tape, a dicing tape when processing a semiconductor wafer, a brittle member such as an ultrathin glass substrate, a support tape for a member that easily warps such as a plastic film, a coreless FPC substrate, etc. Can be suitably used.
The base material is, for example, a sheet made of a transparent resin such as acrylic, olefin, polycarbonate, vinyl chloride, ABS, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), nylon, urethane, polyimide, or a network structure. And a sheet having a hole and the like.

The adhesive tape of the present invention can be used, for example, when bonding a support plate for the purpose of protecting a semiconductor wafer when a semiconductor wafer is subjected to chemical treatment, heat treatment, or heat generation. After these processes are completed, the support plate can be easily peeled from the semiconductor wafer by irradiating light.
The step of bonding the semiconductor wafer and the support plate using the adhesive tape of the present invention, the step of subjecting the semiconductor wafer to chemical treatment, heat treatment, or heat generation treatment while being bonded to the support plate, and the above There is also a semiconductor wafer processing method comprising a step of irradiating the adhesive tape with light after the treatment to generate a gas from the tetrazole compound in the adhesive layer, and a step of peeling the support plate and the adhesive tape from the semiconductor wafer. Moreover, it is one of the present inventions.

The adhesive tape of the present invention can be used, for example, when bonding a support plate for the purpose of protecting a semiconductor wafer when forming a through-hole having electrodes on the semiconductor wafer. After these processes are completed, the support plate can be easily peeled from the semiconductor wafer by irradiating light.
The step of bonding the semiconductor wafer having a groove with the support plate using the adhesive tape of the present invention and the surface opposite to the side of the semiconductor wafer bonded to the support plate are ground to penetrate the groove. A step of forming a hole, a step of forming an electrode portion around the through-hole of the semiconductor wafer, and after the preparation of the electrode portion, the adhesive tape is irradiated with light to generate a gas from the tetrazole compound in the adhesive layer A TSV wafer manufacturing method including a process and a process of peeling the support plate and the adhesive tape from the semiconductor wafer is also one aspect of the present invention.

According to the present invention, there are provided a tetrazole compound or a salt thereof excellent in heat resistance and excellent in reactivity to a long wavelength ultraviolet ray having a wavelength of 300 nm or more, an adhesive composition containing the tetrazole compound or a salt thereof, and an adhesive tape. be able to.

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) A compound represented by the following formula (A ′) is prepared as a raw material for preparing the tetrazole compound represented by the formula (A), and sodium azide is added to the compound and heated, whereby the above formula (A) The tetrazole compound represented by this was obtained.

(2) Production of Adhesive Composition and Adhesive Tape A reactor equipped with a thermometer, a stirrer, and a cooling tube was prepared, and 94 parts by weight of 2-ethylhexyl acrylate, 1 part by weight of acrylic acid, 2- After adding 5 parts by weight of hydroxyethyl acrylate, 0.01 part by weight of lauryl mercapcaptan 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 a photopolymerization initiator (Esacure One, manufactured by Nippon Shibel Hegner) and 2.5 parts by weight of a polyisocyanate-based crosslinking agent (Coronate L45, manufactured by Nippon Polyurethane) are mixed and bonded to 100 parts by weight of solid content. An ethyl acetate solution of the agent was prepared.

10 parts by weight of the tetrazole compound represented by the above formula (A) obtained, and 1 part by weight of 9,10-diglycidyloxyanthracene as a photosensitizer with respect to 100 parts by weight of the resin solid content of the ethyl acetate solution of the adhesive Parts were mixed to obtain an adhesive composition.

The obtained adhesive composition was applied on one side of a transparent polyethylene terephthalate film having a thickness of 50 μm and subjected to corona treatment on both sides with a doctor knife so that the thickness of the dry film was 30 μm. The coating solution was dried by heating for 5 minutes. Next, the adhesive composition was applied on the other surface of the polyethylene naphthalate with a doctor knife so that the thickness of the dried film was 30 μm, and the coating solution was dried by heating at 110 ° C. for 5 minutes. . Then, static curing was performed at 40 ° C. for 3 days to obtain an adhesive tape having an adhesive layer on both sides.

(Example 2)
A compound represented by the following formula (B ′) was prepared as a raw material, and sodium azide was added thereto and heated to obtain a tetrazole compound represented by the above formula (B).
An adhesive composition and an adhesive tape were produced in the same manner as in Example 1 except that the tetrazole compound represented by the obtained formula (B) was used.

(Example 3)
A compound represented by the following formula (C ′) was prepared as a raw material, and sodium azide was added thereto and heated to obtain a tetrazole compound represented by the above formula (C).
An adhesive composition and an adhesive tape were produced in the same manner as in Example 1 except that the tetrazole compound represented by the above formula (C) was used.

Example 4
A compound represented by the following formula (D ′) was prepared as a raw material, and sodium azide was added thereto and heated to obtain a tetrazole compound represented by the above formula (D).
An adhesive composition and an adhesive tape were produced in the same manner as in Example 1 except that the tetrazole compound represented by the obtained formula (D) was used.

(Example 5)
A compound represented by the formula (E ′) was prepared as a raw material, and sodium azide was added thereto and heated to obtain a tetrazole compound represented by the formula (E).
An adhesive composition and a tape were produced in the same manner as in Example 1 except that the tetrazole compound represented by the obtained formula (E) was used.

(Example 6)
A compound represented by the formula (F ′) was prepared as a raw material, and sodium azide was added thereto and heated to obtain a tetrazole compound represented by the formula (F).
An adhesive composition and a tape were produced in the same manner as in Example 1 except that the tetrazole compound represented by the obtained formula (F) was used.

(Example 7)
The salt of the tetrazole compound represented by the formula (E *) was obtained by reacting the compound represented by the formula (E) obtained in Example 5 with sodium hydroxide.
An adhesive composition and a tape were produced in the same manner as in Example 1 except that the tetrazole compound sodium salt represented by the obtained formula (E *) was used.

(Example 8)
A salt of the tetrazole compound represented by the formula (F *) was obtained by reacting the compound represented by the formula (F) obtained in Example 6 with sodium hydroxide.
An adhesive composition and a tape were produced in the same manner as in Example 1 except that the tetrazole compound sodium salt represented by the obtained formula (F *) was used.

(Comparative Example 1)
Instead of 20 parts by weight of the tetrazole compound represented by the formula (A), 20 parts by weight of azobisisobutyronitrile (AIBN), 3 parts by weight of diethylthioxanthone instead of 1 part by weight of 9,10-diglycidyloxyanthracene An adhesive composition and an adhesive tape were obtained in the same manner as in Example 1 except that was added.

(Comparative Example 2)
An adhesive composition and an adhesive tape were obtained in the same manner as in Example 1 except that 20 parts by weight of a bistetrazole sodium salt was blended in place of 20 parts by weight of the tetrazole compound represented by the above formula (A).

(Evaluation)
The tetrazole compounds used in Examples and Comparative Examples and the adhesive tapes obtained in Examples and Comparative Examples were evaluated by the following methods.
The results are shown in Table 1.

(1) Evaluation of reactivity to ultraviolet rays having a wavelength of less than 300 nm A 0.1% DMSO solution of the tetrazole compound (or AIBN) obtained in Examples and Comparative Examples was prepared, and the solution was put in a 1 cm square quartz cell. . Using a spot UV lamp UV irradiator (REX-1000 manufactured by Asahi Spectroscopic Co., Ltd.) capable of irradiating UV light with a wavelength of 254 nm from the side of the quartz cell, UV light is irradiated for 5 minutes at an intensity of 254 nm and an illuminance of 50 mW / cm ^2. It was. By visually observing, a case where bubbles were generated in the quartz cell was evaluated as “◯”, and a case where bubbles were not generated in the quartz cell was evaluated as “x”.

(2) Evaluation of reactivity to ultraviolet rays having a wavelength of 300 nm or more A 0.1% DMSO solution of the tetrazole compound (or AIBS) obtained in Examples and Comparative Examples was prepared, and 1 mL of the solution was obtained with two quartz plates. It was pinched and sealed. A filter that cuts a wavelength of 300 nm or less was attached to an ultra-high pressure mercury lamp ultraviolet irradiator, and ultraviolet irradiation was performed for 5 minutes at a wavelength of 365 nm and an intensity of 50 mW / cm ² . By visually observing, a case where bubbles were generated between the quartz plates was evaluated as “◯”, and a case where bubbles were not generated between the quartz plates 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. A glass plate having a diameter of 20 cm and a thickness of 1 mm was attached to the surface opposite to the surface attached to the silicon wafer. The laminate was heated at 200 ° C. for 1 hour and then returned to room temperature.
When the surface after heating was visually observed and the area where peeling was observed was 5% or less of the whole, “◯”, and when it exceeded 5% and was 10% or less, “△” The case of exceeding 10% was evaluated as “x”.

(4) Evaluation of gas generation property and peelability after ultraviolet irradiation 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. A quartz plate having a diameter of 20 cm and a thickness of 1 mm was attached to the surface opposite to the surface attached to the silicon wafer.
Next, using an ultra-high pressure mercury lamp from a quartz plate, a filter that cuts a wavelength of 300 nm or less is attached, and the illuminance is adjusted so that the irradiation intensity of the ultraviolet light having a wavelength of 300 nm or more is 80 mW / cm ^{2 in} terms of 365 nm. Then, irradiation was performed for 4, 6, 8, and 10 minutes.
In the case of irradiation for each time, gas generation and peelability were evaluated according to the following criteria.

(Evaluation criteria for gas generation)
When the area where the gas is generated is 90% or more of the whole when visually observed from the quartz plate side, “◯” indicates that the area where the gas is generated is 80% or more of the whole, 90 The case where it was less than% was evaluated as “Δ”, and the case where the area where gas was generated was less than 80% of the whole was evaluated as “x”.

(Evaluation criteria for peelability)
After the silicon wafer was placed on the suction table so that the quartz plate was on the upper surface, the end of the quartz plate was pulled with a suction cup, and the case where it could be peeled off was evaluated as “◯”, and the case where it was not peeled off was evaluated as “x”.

(5) Measurement of molar extinction coefficient 0.03-0.05 mmol of the tetrazole compound (or AIBN) obtained in Examples and Comparative Examples was weighed and dissolved in 10 mL of dimethylformamide, and the resulting solution was manufactured by Hitachi, Ltd. The absorption spectrum was measured using U-3000. Using the absorbance in the obtained absorption spectrum, the molar extinction coefficient was determined according to the following formula.
ε = A / c × d
In the formula, ε represents the molar extinction coefficient, A represents the absorbance, c represents the molar concentration, and d represents the cell thickness.
The molar extinction coefficient was determined within the wavelength range of 300 to 400 nm and the wavelength of 305 to 400 nm. When the maximum value of the molar extinction coefficient was 100 L / mol · cm or more, “◯” was less than 100 L / mol · cm. The case was evaluated as “×”.

(6) Measurement of weight residual ratio 5-10 mg of tetrazole compounds (or AIBS) obtained in Examples and Comparative Examples were weighed on an aluminum pan of a thermobalance (TG / DTA6200, manufactured by SII), and in an air atmosphere (flow rate) 200 mL / min) and the rate of weight loss when the temperature was raised from 120 ° C. to 200 ° C. under the condition of a temperature rising rate of 5 ° C./min. The case where the weight residual ratio was 95% or more was evaluated as “◎”, the case where it was 85% or more and less than 95% was evaluated as “◯”, and the case where it was less than 85% was evaluated as “x”.

ADVANTAGE OF THE INVENTION According to this invention, the tetrazole compound or its salt which is excellent in heat resistance and excellent in the reactivity with respect to long wavelength ultraviolet rays with a wavelength of 300 nm or more, the adhesive composition containing this tetrazole compound or its salt, and an adhesive tape can be provided. .

Claims (1)

An adhesive comprising an adhesive component and a tetrazole compound having a molecular weight of 800 or less and having a structure in which the 5-position between two tetrazole structures is bonded to the main chain with a group having an aromatic ring or a salt thereof A composition comprising:
A tetrazole compound having a molecular weight of 800 or less and a structure in which the 5-position between two tetrazole structures is bonded to the main chain with a group having an aromatic ring or a salt thereof is represented by the following formulas (A) to (F Or a salt thereof.
An adhesive composition characterized by that.