JP2000256637A - Crosslinkable adhesive composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive composition which does not contain chlorine and shows excellent adhesion to various substrates and adherends and slowly advances crosslinking reaction at room temperature after laminating substrates or adherends through the adhesive compositions to improve the heat resistance of the adhesive layer. SOLUTION: Crosslinkable adhesive compositions comprise, as the major components, (A) 20-100 pts.wt. epoxy modified block copolymer obtained by epoxidizing a block copolymer composed of (A1) a polymer block mainly having a monomer unit based on a vinyl aromatic compound and (A2) a polymer block monomer mainly having a monomer unit based on a conjugated diene, (B) 0-80 pts.wt. tackifier (provided that the sum of components (A) and (B) is 100 pts.wt.), (C) 0.01-10 pts.wt. curing accelerator which accelerates the crosslinking reaction of the epoxy group of the epoxy modified block copolymer (A), and (D) 50-2,000 pts.wt. solvent which can dissolve epoxy modified block copolymer (A) or tackifier (B).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an adhesive composition containing an epoxy-modified block copolymer. More specifically, the present invention relates to a specific epoxy-modified block copolymer, a tackifier, a curing accelerator for accelerating a crosslinking reaction of an epoxy group, and an adhesive composition containing a solvent of the copolymer as a main component. It does not contain chlorine, which harms the living environment by generating, and exhibits excellent adhesiveness to various bonding substrates and adherends adhered thereto, and at the time of bonding, slowly after bonding. The present invention relates to an adhesive composition capable of promoting a crosslinking reaction.

[0002]

2. Description of the Related Art In recent years, as seen in composite materials in the form of laminates, composites, and the like, composites by bonding various industrial materials have been actively performed. The demands for high functionality by these composites include the above-mentioned various industrial materials, for example, synthetic resins having or without polar groups, iron, aluminum,
It is necessary to provide a high-grade adhesive composition suitable for bonding between dissimilar or similar materials such as metal materials such as copper, cellulosic materials such as wood and paper, or glass, and compositions containing improved adhesive polymers. Materials are frequently used as essential components. As described above, the functionalization of the composite material is often performed by using a highly functionalized adhesive polymer or a composition containing the same as a main component between the bonding substrate and the adherend. It has been achieved.

[0003] The fields in which composite materials using the above adhesive composition are used include laminates for furniture and other woodwork, composite boards, building or building boards, bags, cans, and packaging-related laminates. , From other bookbinding areas,
Starting with vehicles centered on automobiles, electrical equipment, office equipment,
There is a very wide range of fields of use, from constituent materials such as household goods. Therefore, as described above, the types of the base material and the adherend material are also extremely large, and the uses thereof are also very diversified. Therefore, various performances suitable for the purpose are required for the adhesive composition. .

Examples of the adhesive composition using a solvent include a nitrile rubber composition, a composition using a styrene elastomer such as SBR and SBS, a chloroprene rubber composition,
There are others. Among them, the nitrile rubber-based composition and the composition using the styrene-based elastomer have a problem in adhesiveness that the applied base material and adherend are limited. On the other hand, chloroprene rubber-based compositions are widely used, especially in the field of building materials and automotive components, due to their various adhesive properties.However, since they contain chlorine in their molecular chains, they may generate dioxins during their incineration and disposal. Which is not preferable for environmental protection. Incidentally, the chloroprene rubber-based adhesive composition is used in a large amount for bonding a waterproofing sheet material for a roof. However, if the composition is such that the open time for bonding can be extended, the cohesive force is reduced, and the adhesive strength is reduced. There is a problem in that the portion does not have sufficient heat resistance to withstand high temperatures in summer.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a composition which does not contain chlorine which is harmful to the environment at the time of combustion and disposal and has excellent adhesion to various substrates and adherends. Excellent adhesion to plastics such as PET, acrylic resin, polyamide, EVA, polypropylene and polyethylene, rubbers such as EPDM, NBR, SBR, natural rubber, metals such as stainless steel, aluminum and copper, and glass. After bonding the base material and the adherend via the adhesive composition, the crosslinking reaction proceeds slowly at room temperature, greatly improving the heat resistance of the adhesive layer. An object of the present invention is to provide an adhesive composition suitable for bonding between similar or different materials.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above problems, and as a result, have found that a polymer block mainly composed of a monomer unit based on a vinyl aromatic compound and a monomer unit based on a conjugated diene compound are used. To the epoxy-modified block copolymer obtained by epoxidizing a block copolymer consisting of a main polymer block and a tackifier, an epoxy group crosslinking, a curing reaction accelerator and the like and a solvent such as the above copolymer are used. Findings that the composition obtained has good adhesion to various substrates and adherends, can promote the cross-linking reaction of epoxy groups slowly after lamination, and can greatly improve the heat resistance of the adhesive layer. To complete the present invention.

That is, the first aspect of the present invention comprises a polymer block (A1) mainly composed of monomer units based on a vinyl aromatic compound and a polymer block (A2) mainly composed of monomer units based on a conjugated diene compound. 20 to 100 parts by weight of an epoxy-modified block copolymer obtained by epoxidizing a block copolymer (A), and a tackifier (B) 0 to 80
Parts by weight (however, the total of (A) and (B) is 100 parts by weight), and a curing accelerator (C) for promoting a crosslinking reaction of an epoxy group of the epoxy-modified block copolymer (A) 0.01 to 1
0 parts by weight, and an epoxy-modified block copolymer (A) or the epoxy-modified block copolymer and a tackifier (B)
The present invention provides a crosslinkable adhesive composition containing 50 to 2,000 parts by weight of a soluble solvent (D). The second aspect of the present invention is that the content of the epoxy-modified block copolymer (A) and the tackifier (B) in the first adhesive composition is 40 to 85% by weight of the epoxy-modified block copolymer (A). Of the tackifier (B) in an amount of 15 to 60 parts by weight per part. The third aspect of the present invention is the first and second aspects.
The epoxy-modified block copolymer (A) in the adhesive composition of (1) has a polymerization ratio of the polymer block (A1) and the polymer block (A2) of 5/95 to 70/30 by weight.
Having a weight average molecular weight of 5,000 to 60
000 and an epoxy equivalent of 200 to 5,000.
An adhesive composition is provided. A fourth aspect of the present invention is that the polymer block (A2) of the epoxy-modified block copolymer (A) in the first to third adhesive compositions is hydrogenated, and the degree of hydrogenation is 1 to 99%. Provided is an adhesive composition comprising a hydrogenated conjugated diene compound copolymer. A fifth aspect of the present invention is that the tackifier (B) in the first to fourth adhesive compositions comprises a rosin ester, a maleic acid-modified rosin, an aliphatic petroleum resin, an alicyclic petroleum resin, an aromatic petroleum resin, An adhesive composition is provided which is at least one selected from the group consisting of hydrogenated petroleum resins obtained by hydrogenating these petroleum resins, terpene-modified phenol resins, and coumarone-indene-styrene copolymer resins. In a sixth aspect of the present invention, the curing accelerator (C) in the adhesive composition is selected from the group consisting of an acidic substance, a basic substance, a heat-decomposition type cationic curing accelerator, and an ultraviolet or electron beam decomposition type cation accelerator. An adhesive composition comprising at least one selected from the group consisting of: A seventh aspect of the present invention provides an adhesive composition wherein the solvent (D) in the first to sixth adhesive compositions is at least one selected from the group consisting of toluene, ethyl acetate, cyclohexane and n-hexane. I do. In the eighth aspect of the present invention, the first or seventh adhesive composition further comprises an oil or a plasticizer (E) compatible or soluble in the epoxy-modified block copolymer (A). (A)
And a tackifier (B) in a ratio of 10 parts by weight or less based on 100 parts by weight in total. Further, a ninth aspect of the present invention is that an inorganic filler (F) is further added to the first to eighth adhesive compositions, based on a total of 100 parts by weight of the epoxy-modified block copolymer (A) and the tackifier (B). An adhesive composition which is added at a ratio of not more than 50 parts by weight. In a tenth aspect of the present invention, the adhesive composition according to any one of the first to ninth aspects of the present invention further comprises a crosslinking agent (G) in a total of 100 parts by weight of the epoxy-modified block copolymer (A) and the tackifier (B). The present invention provides an adhesive composition containing 1 to 40 parts by weight of the adhesive composition. An eleventh aspect of the present invention is the adhesive composition according to any one of the first to tenth aspects, further comprising a lubricant, an antioxidant, a pigment, a dye, an organic filler, a fragrance, an ultraviolet absorber, or a stabilizer. Provided is an adhesive composition to which an agent is added. In addition, in a twelfth aspect of the present invention, in the first to eleventh aspects, the adhesive composition is applied to at least one surface of the substrate and the adherend, and after removing the solvent (D), the substrate and the adherend are attached. In addition, an object of the present invention is to provide an adhesion method in which a crosslinking reaction of the epoxy-modified block copolymer (A) proceeds at a temperature of room temperature to 50 ° C.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The epoxy-modified block copolymer (A) used in the present invention comprises a polymer block (A1) mainly composed of a monomer unit based on a vinyl aromatic compound and a polymer block mainly composed of a monomer unit based on a conjugated diene compound. A block copolymer with (A2) or a polymer block (A2) obtained by epoxidizing a carbon-carbon double bond derived from a conjugated diene of a partially hydrogenated block copolymer. is there.

Examples of the vinyl aromatic compound relating to the polymer block (A1) include styrene, α-methylstyrene, vinyltoluene, p-tert-butylstyrene, divinylbenzene, p-methylstyrene, 1,1-diphenylstyrene and the like. And styrene is preferable among them.
As the polymer block (A1) according to the present invention, in addition to using one of these, two or more of them can be used in combination.

The conjugated diene compound relating to the polymer block (A2) includes butadiene, isoprene, 1,3
-Pentadiene, 2,3-dimethyl-1,3-butadiene, piperylene, 3-butyl-1,3-octadiene,
Examples thereof include phenyl-1,3-butadiene, and among these, butadiene and isoprene are preferred. As the polymer block (A2) according to the present invention, in addition to using one of these, two or more of them can be used in combination.

The epoxy-modified block copolymer (A) has a polymer block (A1) mainly composed of a monomer unit based on a vinyl aromatic compound and a polymer block (A2) mainly composed of a monomer unit based on a conjugated diene compound. And the polymerization ratio is preferably 5/95 to 70/30 by weight.
However, it is more preferably 10/90 to 60/40.

The weight average molecular weight of the epoxy-modified block copolymer (A) is preferably from 5,000 to 600,000.
0, more preferably 10,000 to 500,000.
0. Also, its molecular weight distribution (weight average molecular weight (M
w) / number average molecular weight (Mn)), that is, (Mw) / (Mn) is preferably 10 or less.

The molecular structure of the epoxy-modified block copolymer may be linear, branched, radial or any combination thereof, and A1-A2-A
1, A2-A1-A2, (A1-A2-) 4 Si, A1
Examples thereof include a block copolymer having a structure such as -A2-A1-A2-A1 and mainly containing a vinyl aromatic compound and a conjugated diene compound. The unsaturated bond derived from the conjugated diene compound of the block copolymer constituting the raw material of the epoxy-modified block copolymer has a hydrogenation rate of 1 to 99%.
Partially hydrogenated ones in the range are also preferably used, and more preferably the hydrogenation ratio is in the range of 1 to 90%. In addition, you may mix and use the hydrogenated thing and the raw material which is not hydrogenated.

The method for producing an epoxy-modified block copolymer according to the present invention can employ various means. For example, JP-B-40-23798, JP-B-47-3252, JP-B-48-2423, JP-B-46-32415, JP-B-49-36957, JP-B-43-17979, and JP-B-46-32415. According to the methods described in JP-B-56-28925, a vinyl aromatic compound-conjugated diene compound block copolymer can be synthesized in an inert solvent using a lithium catalyst or the like. Further, by a method described in JP-B-42-8704, JP-B-43-6636, or JP-A-59-133203, hydrogenation was carried out in an inert solvent in the presence of a hydrogenation catalyst to give a partial solution. The above-mentioned vinyl aromatic compound-conjugated diene compound block copolymer which is hydrogenated can be synthesized.

The epoxy-modified block copolymer (A) according to the present invention is produced by epoxidizing the above block copolymer. Epoxidation can be carried out by reacting the block copolymer with an epoxidizing agent such as hydroperoxides and peracids in an inert solvent. Examples of peracids include formic acid, peracetic acid, and perbenzoic acid.
Examples of the hydroperoxides include those obtained by using a mixture of tungstic acid and caustic soda with hydrogen peroxide, or using an organic acid with hydrogen peroxide, or using molybdenum hexacarbonyl with tertiary butyl hydroperoxide. .

The amount of the epoxidizing agent used is not particularly strictly limited, and the optimum amount in each case depends on the particular epoxidizing agent used, the desired degree of epoxidation, and the particular block copolymer used. Can be selected according to the properties such as. The inert solvent used at the time of epoxidation is used for the purpose of lowering the viscosity of the raw material block copolymer, stabilizing by diluting the epoxidizing agent, and when peracetic acid is used as the epoxidizing agent, Aromatic compounds, ether compounds, ester compounds and the like can be suitably used. Particularly preferred solvents are hexane, cyclohexane,
Toluene, benzene, ethyl acetate, carbon tetrachloride, and chloroform.

The reaction conditions for the epoxidation are not strictly limited, and the reaction temperature range can be appropriately selected depending on the reactivity of the epoxidizing agent used. For example, when peracetic acid is used as the epoxidizing agent, 0 to 7
0 ° C. is preferred. If the temperature is lower than 0 ° C., the reaction tends to be slow. If the temperature is higher than 70 ° C., decomposition of peracetic acid tends to occur.
When tertiary butyl hydroperoxide / molybdenum dioxide diacetyl acetate, which is one example of hydroperoxide, is used, the temperature is preferably from 20 to 150 ° C. When the temperature is lower than 20 ° C. or higher than 150 ° C., the same tendency as in the case of peracetic acid is obtained. No special operation is required for the epoxidation reaction operation. For example, the reaction mixture may be stirred for 2 to 10 hours. The obtained epoxy-modified block copolymer (A) may be isolated by a commonly used method as appropriate. For example, a method of precipitating with an inert solvent, a method of putting the polymer into hot water with stirring, or the like. , A method of removing the solvent by distillation, a method of directly removing the solvent, and the like.

The epoxy-modified block copolymer (A) according to the present invention preferably has an epoxy equivalent of 200 to 5.0.
00, and particularly preferably 250 to 1,500. If the epoxy equivalent is less than 200, the density of epoxy groups in the molecule will be high, and the epoxy groups may easily react with each other, resulting in lack of storage stability. Conversely, if it exceeds 5,000, the crosslinked product obtained cannot have a sufficient crosslink density and may not have satisfactory properties such as heat resistance and solvent resistance. The epoxy equivalent of the epoxy-modified block copolymer (A) according to the present invention is represented by the number of grams of the copolymer (A) per 1 g of epoxy group, and is expressed by 0.1N hydrobromic acid. It is calculated by titration and epoxy equivalent = (1,000 × weight of epoxy-modified block copolymer (g) / (titration amount of hydrobromic acid (ml) × factor of hydrobromic acid)).

Further, a tackifier (B) is used as an optional component of the crosslinkable adhesive composition according to the present invention. The addition of the tackifier (B) improves the adhesive strength of the adhesive composition according to the present invention, and particularly increases the initial adhesive strength. Examples of the tackifier (B) used here include rosin-based resins, terpene-based resins, petroleum resins, hydrogenated petroleum resins, cumarone-based resins, styrene-based resins, and phenol-based resins.

More specifically, rosin resins include gum rosin, wood rosin, polymerized rosin, and derivatives thereof, such as disproportionated rosin, hydrogenated rosin, dehydrogenated rosin, rosin-glycerin ester, rosin-pentaerythritol ester, and the like. Rosin ester, maleic acid-modified rosin, rosin metal salt, phenol-modified rosin and the like. Examples of the terpene-based resin include β-pinene polymer, α-pinene polymer, modified pinene polymer, mixed pinene polymer, terpene polymers such as dipentel, limonene, myrcene, bornylene, and camphene, and terpene-modified phenol resins. can do.

As the petroleum resin and the hydrogenated petroleum resin,
C ₅ -C ₁₀ aliphatic petroleum resin having an unsaturated bond derived from petroleum fractions, alicyclic petroleum resin or aromatic petroleum resin,
Examples thereof include hydrogenated petroleum resins obtained by hydrogenating them, homo- or copolymers of cyclopentadiene, and hydrogenated cyclopentadiene. Examples of the coumarone-based resin include a coumarone resin, a coumarone-indene resin, and a coumarone-indene-styrene copolymer resin. Examples of the styrene-based resin include a low-molecular-weight polymer containing styrene as a main component, a homopolymer, a copolymer of styrene, α-methylstyrene, vinyltoluene, butadiene rubber, and the like. it can. Examples of phenolic resins include reaction products of phenols such as phenol, cresol, xylenol, resorcinol, p-tert-butylphenol, and p-phenylphenol with aldehydes such as formaldehyde, acetaldehyde, and furfural, and rosin-modified phenol resins. Examples can be given.

Among these various tackifiers (B), the compatibility with the epoxy-modified block copolymer (A), the solubility in the solvent (D) described later, and the improvement in adhesion to various substrates and adherends From the point of effect, rosin ester, maleic acid-modified rosin,
Aliphatic petroleum resins, alicyclic petroleum resins, aromatic petroleum resins, hydrogenated petroleum resins, terpene-modified phenol resins, and coumarone-indene-styrene copolymer resins are particularly preferably used.

The tackifier (B) in the adhesive composition according to the present invention is added in an amount of 100 parts by weight in total with the epoxy-modified block copolymer (A). The tackifier (B) is used in an amount of 80 to 0 parts by weight based on 20 to 100 parts by weight, preferably the former (A).
The latter (B) is 70 to 10 parts by weight with respect to 30 to 90 parts by weight, and more preferably the latter is 60 to 15 parts by weight with respect to the former 40 to 85 parts by weight.

As a constituent of the crosslinkable adhesive composition according to the present invention, a curing accelerator (C) for accelerating the crosslinking reaction of an epoxy group is further used. Examples of the curing accelerator (C) include an acid accelerator, a basic accelerator, a heat-decomposition type cationic curing accelerator, and an ultraviolet or electron beam decomposition type cation accelerator. These exemplified accelerators will be described with reference to more specific examples.

Examples of the acid promoter include sulfuric acid, hydrochloric acid,
Inorganic acids such as nitric acid and the like, as a basic accelerator,
For example, pyridine, isoquinoline, N, N-dimethylcyclohexylamine, α-picoline, tri-n-butylamine, triethylamine, N-ethylformoline,
N-dimethylaniline, N- (β-hydroxyethyl)
Amines such as amines and N-ethyl-3,5-diethylformoline; alkali metal salts such as sodium carbonate, potassium carbonate and calcium carbonate; organic metals obtained from organic acids and lithium, magnesium, zinc, cadmium, aluminum, etc. Salts: metal hydroxides such as sodium hydroxide, potassium hydroxide and lithium hydroxide.

On the other hand, examples of a heat decomposition type cation curing accelerator and an ultraviolet or electron beam decomposition type cation accelerator include, for example, antimony hexafluoride-based aromatic sulfonium salts (manufactured by Sanshin Chemical Co., SI-100L), allyldiazonium salts ( For example, P-33 manufactured by Asahi Denka Co., Ltd., an allyl iodonium salt (eg, CD-1012 manufactured by Sartomer), an allyl sulfonium salt (eg, FC-512, FC-50 manufactured by 3M)
9; Sartomer, CD-1011; Daicel Chemical Industries, Ltd., DAICAT11; GE, UVE101
4: Union Carbide Co., Ltd., UVI-6974, UV
I-6970, UVI-6990, UVI-6950;
Asahi Denka Co., SP-170, SP-150), Allen-
Ion complex (for example, CG-24-6 manufactured by Ciba-Geigy)
1) and the like. Further, triphenylphosphine,
Examples include phosphines such as tricyclophosphine, tributylphosphine, allyldiphenylphosphine, tribenzylphosphine, and tolylphosphine.

As a component of the crosslinkable adhesive composition according to the present invention, the epoxy-modified block copolymer (A) or a solvent which dissolves the epoxy-modified block copolymer and the tackifier (B) may be used. D). Here, "dissolve" means that at least 10 g of the epoxy-modified block copolymer or tackifier (B) can be dissolved in 100 g of a solvent at 25 ° C. As the solvent (D) used in the present invention, an aliphatic compound, an alicyclic compound, an aromatic compound,
Examples thereof include an ether compound and an ester compound. Preferred solvents include hexane, cyclohexane, toluene, benzene, ethyl acetate, carbon tetrachloride, chloroform and the like.
Toluene, ethyl acetate, cyclohexane, and n-hexane are particularly preferred from the viewpoint of solubility, workability, cost, and influence on the working environment.

As described above, the crosslinkable adhesive composition according to the present invention comprises an epoxy-modified block copolymer (A), a tackifier (B), a curing accelerator (C) involved in a crosslinking reaction of epoxy groups, And epoxy-modified block copolymer (A) or epoxy-modified block copolymer and tackifier (B)
And a solvent (D) having solubility in water. (C) is used in an amount of 0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the total of (A) and (B). D) 50-2000
Parts by weight, preferably 100 to 1500 parts by weight, particularly preferably 150 to 1000 parts by weight.

The relationship between the use range of each component and the effect of the present invention will be described in detail. Adhesion occurs when the component (A) is less than 20 parts by weight, that is, when the amount of the tackifier (B) exceeds 80 parts by weight, in a total of 100 parts by weight of the epoxy-modified block copolymer (A) and the tackifier (B). It is inferior in cohesive strength as an agent, and as a result, when the bonded portion is exposed to a high temperature, peeling is apt to occur, so that it must be avoided. If the curing accelerator (C) is less than 0.01, the effect of accelerating the curing of the epoxy-modified block copolymer (A) cannot be obtained, and a long time is required for curing. Conversely, if the amount exceeds 10 parts by weight, the effect of accelerating the curing reaches saturation, which is not preferable because it causes a cost increase. If the amount of the solvent (D) is less than 50 parts by weight, the viscosity of the adhesive composition becomes too high, so that the workability and the coatability deteriorate, which is not preferable. Conversely, if the amount exceeds 2,000 parts by weight, a sufficient film thickness required for adhesion cannot be obtained when the solvent is removed after application to the substrate or the adherend, which is not preferable.

In the present invention, the above-mentioned component (A),
An epoxy-modified block copolymer is added to the adhesive composition comprising (B), (C) and (D) in order to improve the adhesion or wettability between the adhesive composition and a substrate or an adherend. An oil or a plasticizer (E) compatible with (A) and the tackifier (B) can be added and mixed for use. The term "compatible" as used herein refers to a state in which two or more types of substances are uniformly mixed, and the mixed substances in the uniform state are not separated even after a long time. Whether or not they are compatible with each other is generally determined by 2 in the case of a solution using a solvent.
This can be achieved by dissolving at least one kind of substance in a solvent, stirring the mixture, and allowing it to stand for one day or more to visually observe whether the solution has separated into two or more layers. In addition, dissolution means that when a solid substance is mixed with a liquid substance, both become uniform and transparent.However, it is generally determined whether or not the two substances are dissolved after stirring and mixing the two. It is possible by visually observing the presence or absence of a solid substance.

The oil or plasticizer (E) has a boiling point of 1
It is a liquid of about 00 to 200 ° C., specifically,
Examples of the oil include paraffinic, naphthenic, and aroma-based process oils, liquid paraffin, and vegetable oils. Specific examples of the plasticizer include dimethyl phthalate, diethyl phthalate, diisobutyl phthalate, dibutyl phthalate, and oleic acid. Butyl, ethoxyethyl oleate, butyl stearate, epoxidized soybean oil, epoxidized tall oil, fatty acid-2-ethylhexyl, epoxidized linseed oil, butyl epoxy stearate, octyl epoxy stearate, benzyl epoxy stearate, epoxy Dioctyl hexahydrophthalate and the like can be mentioned. Of these, naphthene-based process oil, epoxidized soybean oil, epoxidized linseed oil, and the like are particularly preferred because of their good compatibility with the epoxy-modified block copolymer (A).

The proportion of the oil or plasticizer (E) added to the adhesive composition according to the present invention is 10 to the total of 100 weights of the epoxy-modified block copolymer (A) and the tackifier (B). It is preferably at most 5 parts by weight, more preferably at most 5 parts by weight. When the addition ratio exceeds 10 parts by weight, the adhesive property tends to be remarkably lowered due to seepage of oil or plasticizer.

In the present invention, the above-mentioned component (A),
An adhesive composition comprising (B), (C) and (D) or an adhesive composition further containing an oil or a plasticizer (E) can be used to increase the open time of the adhesive composition, An inorganic filler (F) can be added and contained in order to improve the characteristics of the adhesive strength to the adherend. As the inorganic filler (F) used here, calcium carbonate, magnesium carbonate, kaolin, talc, carbon black,
Bentonite, clay, clay, mica, sericite, glass fiber, carbon fiber, glass powder, glass balloon, shirasu balloon, mica, quartz powder, diatomaceous earth, silica lime, metal powder, alumina, silica, colloidal silica, white carbon, Examples thereof include silicate minerals (calcium silicate, zeolite, pumice powder, slate powder), bentone, silicic anhydride, barium sulfate, calcium sulfate, aluminum hydroxide, zinc oxide, magnesium oxide, molybdenum disulfide, and the like. It may have been subjected to a surface treatment. The addition ratio to the adhesive composition according to the present invention is such that the epoxy-modified block copolymer (A) and the tackifier (B)
Is preferably 50 parts by weight or less based on 100 parts by weight in total.
If the amount exceeds 50 parts by weight, the viscosity of the adhesive becomes too high, which makes handling difficult, and further, a phenomenon of a decrease in adhesiveness starts to be observed.

In the present invention, the above-mentioned component (A),
The epoxy-modified block is added to the adhesive composition comprising (B), (C) and (D) or the adhesive composition further containing an oil or a plasticizer (E) or an inorganic filler (F). Crosslinking agent (G) capable of reacting with the epoxy group of polymer (A)
Can be added, and the adhesiveness can be improved depending on the adherend. Further, by appropriately selecting the crosslinking agent, the crosslinking density can be adjusted, and the elasticity or hardness of the adhesive can be optimized.

Examples of the crosslinking agent (G) include epoxy compounds, and examples thereof include aliphatic, alicyclic, and aromatic compounds having an epoxy group in the main chain or side chain. Examples of the aromatic epoxy compound include glycidyl ethers composed of bisphenol compounds such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, bisphenol S type epoxy resin and epichlorohydrin; bisphenol A, bisphenol F , Bisphenol A
D, glycidyl ethers composed of adducts of alkylene oxides such as ethylene oxide, propylene oxide and butylene oxide to bisphenol compounds such as bisphenol S and epichlorohydrin; novolak epoxy such as phenol novolak epoxy resin and cresol novolak epoxy resin Resin; polyglycidyl ether of polyhydric phenol having at least one aromatic nucleus such as trisphenolmethane triglycidyl ether or an alkylene oxide adduct thereof; hydrogenated product of the aromatic epoxy resin; bromine of the aromatic epoxy resin And the like.

Examples of the alicyclic epoxy compound include compounds having a cyclohexene oxide group, tricyclodecene oxide group, and cyclopentene oxide group. Examples of the alicyclic compound having two epoxy groups include: 4- (1,2-epoxy-1-methylethyl) -1-methyl-7-oxabicyclo- [4.1.
0] heptane, 3,4-epoxy-3-methyl-epoxycyclohexyl-1-methylepoxide, 3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate (Ceroxide, trade name, manufactured by Daicel Chemical Industries, Ltd.) 2021; Union Carbide Co., Ltd., trade name ERL4221), dimer of the carboxylate and caprolactone (Daicel Chemical Industry Co., Ltd., trade name Celloxide 2081), trimer (the company, trade name Celloxide 2083), 4 Dimer (brand name celloxide 2085), pentamer, adduct of hexamer,
3,4-epoxy-1-methylcyclohexylmethyl-
3,4-epoxy-1-methylcyclohexanecarboxylate, 6-methyl-3,4-epoxycyclohexylmethyl-6-methyl-3,4-epoxycyclohexanecarboxylate, 3,4-epoxy-3-methylepoxycyclohexylmethyl -3,4-epoxy-3-
Methyl-epoxycyclohexanecarboxylate, 2
-(3,4-Epoxycyclohexylmethyl-5,5-
Spiro-3,4-epoxy) cyclohexane-meta-dioxane (manufactured by Union Carbide, trade name ERL42)
34), bis (3,4-epoxycyclohexylmethyl) oxalate, bis (3,4-epoxycyclohexylmethyl) adipate (manufactured by Union Carbide, trade name ERL4299), bis (2,3-epoxycyclopentyl) ether, bis ( 3,4-epoxy-6-methylcyclohexylmethyl) adipate, bis (3,4
-Epoxycyclohexylmethyl) bimelate, vinylcyclohexene dioxide (trade name ERL4206, manufactured by Union Carbide Co., Ltd.) and the like.

On the other hand, examples of the aliphatic epoxy resin include diglycidyl ether of 1,4-butanediol;
Diglycidyl ether of 1,6-hexanediol; triglycidyl ether of glycerin; triglycidyl ether of trimethylolpropane; diglycidyl ether of polyethylene glycol; diglycidyl ether of polypropylene glycol; aliphatics such as ethylene glycol, propylene glycol, and glycerin Examples thereof include polyglycidyl ether of polyhydric alcohol, and ethylene oxide and propylene oxide. Further, epoxy plasticizers such as epoxidized soybean oil, epoxidized tall oil, fatty acid-2-ethylhexyl, epoxidized linseed oil, butyl epoxystearate, octyl epoxystearate, benzyl epoxystearate, and dioctyl epoxyhexahydrophthalate. Is mentioned.

As the crosslinking agent (G) capable of reacting with an epoxy group used in the present invention, in addition to those exemplified above, polyhydric alcohols, phenols, amines, carboxylic acids,
At least one compound selected from acid anhydrides and isocyanate compounds can be used. Specifically, polyhydric alcohols include, for example, ethylene glycol, diethylene glycol, polyethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, polypropylene glycol, 1,4-
Butenediol, polybutadienediol, isoprene glycol, 2-methyl-1,3-propanediol,
1,6-hexanediol, 1,5-pentanediol, 1,9-nonanediol, polycaprolactone diol, polycarbonate diol, polyether diol, polybutadiene diol, polyisoprene diol, and diols added to isocyanate groups of diisocyanates Prepolymer diols, sorbitol, glycerin, polycaprolactone triol (Daicel Chemical Industries, Ltd., trade name Placcel 303), polyglycerin (Trade name, PGL), poly (ether-ester) polyol (Trade name, Product name Plaxel P
3403) and the like.

Examples of the amines include ethylenediamine, diethylenetriamine, triethylenetetramine,
Examples include tetraethylenepentamine, propanediamine, hexamethylenediamine, isophoronediamine, phenylenediamine, diaminodiphenylmethane, and the like.

Examples of the carboxylic acids include oxalic acid, succinic acid, adipic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid, linoleic acid, sebacic acid, and the like.
Aliphatic polycarboxylic acids such as dimer acid, etc., tetrahydrophthalic acid, hexahydrophthalic acid, 4-methyltetrahydrophthalic acid, 4-methylhexahydrophthalic acid, cyclohexanedicarboxylic acid, etc., phthalic acid, isophthalic acid And aromatic polycarboxylic acids such as terephthalic acid. Further, examples of the acid anhydride include anhydrides, dimers and trimers of the above-mentioned various polycarboxylic acids. As the isocyanate compound, 1,5
-Naphthylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyl diisocyanate, dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, 1,3-phenylene diisocyanate, 4-
Phenylene diisocyanate, tolylene diisocyanate, butane-1,4-diisocyanate, 1,6-hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene-1,6-diisocyanate, 2,4
4-trimethylhexamethylene-1,6-diisocyanate, lysine diisocyanate, cyclohexane-1,
4-diisocyanate, xylylene diisocyanate,
Examples include isophorone diisocyanate, dicyclohexylmethane-4,4′-diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, and methylcyclohexane diisocyanate.

The amount of the crosslinking agent (G) used in the present invention is as follows:
The amount is preferably 1 to 40 parts by weight, particularly preferably 5 to 30 parts by weight, based on 100 parts by weight of the total of the epoxy-modified block copolymer (A) and the tackifier (B). If the amount is less than 1 part by weight, a high effect as a cross-linking agent is unlikely to be exerted. Conversely, if it exceeds 40 parts by weight, a cured product obtained by crosslinking and curing tends to be too hard and brittle.

Further, in the adhesive composition according to the present invention, an adhesive composition comprising the above-mentioned components (A), (B), (C) and (D) or an oil or a plasticizer (E), In addition to the adhesive composition to which the inorganic filler (F) or the cross-linking agent (G) has been added, other additives such as a lubricant, an antioxidant, a pigment, a dye, and an organic filler may be used within a range not to impair the object of the present invention. Agents, perfumes, ultraviolet absorbers, stabilizers and the like can be added. The use amount of these additives is preferably 10 parts by weight or less, more preferably 5 parts by weight or less, and particularly preferably 3 parts by weight or less, based on 100 parts by weight of the adhesive composition according to the present invention. These additives may be used alone or in combination of two or more.

The material of the substrate and the adherend on which the adhesive composition according to the present invention exhibits good adhesive properties include plastics such as polycarbonate, PET, acrylic resin, polyamide, EVA, polypropylene and polyethylene, EP
Rubbers such as DM, NBR, SBR and natural rubber, metals such as stainless steel, aluminum and copper, and glass are exemplified.

The method for producing the adhesive composition according to the present invention is not particularly limited, and any conventional means can be applied. For example, a solvent (D) is placed in a container provided with a stirrer, While heating to 100 ° C., the mixture is stirred while adding the epoxy-modified block copolymer (A). After the epoxy-modified block copolymer (A) is completely dissolved, add a tackifier (B), and then add an oil or plasticizer (E), an inorganic filler (F), and / or a crosslinking agent (G) as necessary. While stirring. Finally, the addition of the curing accelerator (C)
Moreover, the heat treatment is performed at a temperature of 40 ° C. or less. The preferred solid content concentration is 5 to 50% by weight, and 10 to 40% by weight is particularly preferable from the viewpoint of coating properties and adhesiveness. Moreover, it is preferable that the obtained adhesive composition is stored in a metal closed container at a temperature of 40 ° C. or lower.

The method of bonding between a substrate and an adherend using the adhesive composition according to the present invention is performed by bonding to either one of the substrate and the adherend, or to both of the adhesive surfaces. After applying the agent composition and removing the solvent, the adhesive surfaces are joined together, and at room temperature to 50 ° C.
The cross-linking reaction is allowed to proceed at a temperature of, preferably, 30 to 30 minutes after the adhesive composition is applied, and the adhesive surfaces are joined together.
A method of applying a load of not less than kg / cm ^{2 and} allowing the mixture to stand for not less than 10 minutes for bonding is adopted.

[0046]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. (Examples 1 to 4, Comparative Examples 1 to 3) Materials used in Examples and Comparative Examples are as follows. (1) Epoxy-modified block copolymer (A): Epoxidized SBS1 (manufacturer name, etc.) manufactured by Daicel Chemical Industries, Ltd., trade name Epofriend A1020 (Characteristics) Weight average molecular weight: about 100,000, Epoxy equivalent: about 500, MFR: 10 g / 10 min (190 ° C., 2.16 k
g), elongation at break: 865%, (2) tackifier (B): three types of tackifiers 1 to 3 tackifier 1: rosin ester (manufacturer name, etc.) manufactured by Harima Chemicals, trade name Neotol 85 (Characteristics) Softening point: 87 ° C., Acid value: 0.6, Tackifier 2: alicyclic hydrocarbon (manufacturer name, etc.), manufactured by Idemitsu Petrochemical Co., Ltd., trade name: Imap P-125 (Characteristics) Softening point: 125 ° C., acid value: 0.01 or less, tackifier 3: Terpene-phenol copolymer (manufacturer name, etc.), manufactured by Yashara Chemical Co., Ltd., trade name YS POLYSTAR T-80 (property) Softening point: 80 ° C., acid value: 2 or less, (3) curing accelerator (C): antimony hexafluoride-based aromatic sulfonium salt (manufacturer name, etc.) manufactured by Sanshin Chemical Co., Ltd., trade name SI-100L (4) Solvent (D): cyclohexane

A method for preparing the adhesive compositions used in the examples and comparative examples will be described. First, in Example 1, 233 g of the solvent cyclohexane was placed in a 1-liter separable flask, and 100 g of Epofriend A1020, an epoxy-modified block copolymer, was further charged. % Cyclohexane solution was obtained, and 0.2 g of a curing accelerator SI-100L was added immediately before use to produce an adhesive composition. In Example 2, a cyclohexane solution having a solid content of 30% by weight of the epoxy-modified block copolymer was prepared in the same manner as in Example 1, and a 30% by weight solution of cyclohexane was also prepared for the tackifier 1 at the same time. A cyclohexane solution having a solid content of 30% by weight was obtained by mixing the solutions at a ratio of 80:20 (weight ratio), and a curing accelerator was added immediately before use to prepare an adhesive composition. In Examples 3 and 4, tackifiers 2 and 3 were used instead of tackifier 1 in Example 2, respectively, and 90:10 and 40: 6, respectively, of a cyclohexane solution of an epoxy-modified block copolymer.
Solid content 30% by weight obtained by mixing at a ratio of 0 (weight ratio)
Were obtained, and a curing accelerator was added immediately before use to produce an adhesive composition. Comparative Examples 1, 2 and 3
In Example 1, except that a curing accelerator was not used, solid contents of 30 and 30 were respectively obtained in the same manner as in Examples 1, 2 and 3.
A weight% cyclohexane solution was obtained and provided for the adhesive composition.

The adhesive strength, heat creep resistance and heat peel properties of the adhesive compositions in Examples and Comparative Examples were evaluated by a peel test, a heat creep test and a heat test, respectively. Each test procedure is as follows. (1) Peeling test 50 μm (thickness) × 25 m of the above solution (adhesive composition)
m (width) x 150 mm (length) on a polyethylene terephthalate (PET) film with a # 60 bar coater, air-dry for about 20 minutes,
A μm adhesive-coated substrate (adhering material) was prepared. Similarly, a polycarbonate resin (PC) plate 2 mm (thickness) ×
25mm (width) x 125mm (length), slate plate 1m
m (thickness) x 25 mm (width) x 125 mm (length), E
PDM sheet 1mm (thickness) x 25mm (width) x 125
An adhesive-coated substrate (adhering material) having a length of mm (length) was prepared.
Among these base materials (adhering materials), a polycarbonate resin plate and a PET film, and an EPDM sheet and a slate plate were bonded together, and after applying a load of about 1 kg for 12 hours, the adhesive strength was measured. Adhesive strength (N / 25m
m) was measured according to the conditions of a peeling test at 180 ° at a peeling speed of 200 mm / min. Table 1 shows the results.

(2) Heat creep test The above solution (adhesive composition) was coated with 50 μm (thickness) × 25 m
25 m (width) x 50 mm (length) on a polyethylene terephthalate (PET) film
mm over a length of at least 20 mm using a bar coater and air-dried for about 20 minutes.
The adhesive-coated substrate (adhering material) was prepared. Similarly,
Polycarbonate resin plate 2mm (thickness) x 25mm
Create a (width) x 50mm (length) adhesive coated substrate,
Both were superimposed on each other so that the width of the bonding surface became 25 mm, and after applying a load of about 1 kg for 12 hours, the bonding strength was measured. 1k on the PET film side of the bonded sample
The weight of g was suspended in an oven, the temperature was increased at a rate of 5 ° C./min, and the temperature at which the bonded portion was peeled off and the weight dropped was recorded. Table 1 shows the results.

(3) Heat resistance test The above solution (adhesive composition) was applied to a slate plate 1 mm (thickness).
Coated on # 50 mm (width) x 125 mm (length) and EPDM sheet 1 mm (thickness) x 50 mm (width) x 125 mm (length) with # 60 bar coater, air dried for about 20 minutes, then adhesive film An adhesive-coated substrate (adhering material) having a thickness of about 30 μm was prepared. After bonding them together, applying a load of about 1 kg and leaving them for 12 hours, put them in an oven at 80 ° C.
It was taken out after 96 hours, and the presence or absence of floating or peeling of the bonded portion was observed. Table 1 shows the results.

[0051]

[Table 1]

[0052]

By using the adhesive composition according to the present invention, it can be suitably used as an adhesive giving good adhesive strength, heat creep resistance and heat peelability between various substrates and adherends. Do you get it.

Claims (12)

[Claims] 1. Epoxidation of a block copolymer consisting of a polymer block (A1) mainly composed of monomer units based on a vinyl aromatic compound and a polymer block (A2) mainly composed of monomer units based on a conjugated diene compound. 20 to 100 parts by weight of the epoxy-modified block copolymer (A), 0 to 80 parts by weight of the tackifier (B) (the total of (A) and (B) is 100 parts by weight), and the epoxy-modified block copolymer 0.01 to 10 parts by weight of a curing accelerator (C) for accelerating the crosslinking reaction of the epoxy group of the union (A), and adhesion with the epoxy-modified block copolymer (A) or the epoxy-modified block copolymer (A) Soluble solvent (D) of imparting agent (B) 5
A crosslinkable adhesive composition containing 0 to 2,000 parts by weight as a main component. 2. The content of the epoxy-modified block copolymer (A) and the tackifier (B) is from 40 to 85 parts by weight of the epoxy-modified block copolymer (A) with respect to the content of the tackifier (B) 15 The adhesive composition according to claim 1, wherein the amount is from 60 to 60 parts by weight. 3. An epoxy-modified block copolymer (A)
Is a polymer block (A1) and a polymer block (A2)
And a polymerization ratio of 5/95 to 70/30 by weight, and a weight average molecular weight of 5,000 to 600,000.
The adhesive composition according to claim 1 or 2, wherein the epoxy equivalent is 0 to 200 to 5,000. 4. The adhesive according to claim 1, wherein the polymer block (A2) is a hydrogenated conjugated diene compound copolymer having a hydrogenation ratio of 1 to 99%. Composition. 5. The method according to claim 1, wherein the tackifier (B) is a rosin ester,
Maleic acid-modified rosin, aliphatic petroleum resin, alicyclic petroleum resin, aromatic petroleum resin, hydrogenated petroleum resin obtained by hydrogenating these petroleum resins, terpene-modified phenol resin, cumarone-indene-styrene copolymer resin The adhesive composition according to any one of claims 1 to 4, which is at least one member selected from the group. 6. The curing accelerator (C) comprises at least one selected from the group consisting of an acidic substance, a basic substance, a heat-decomposable cationic curing accelerator, and an ultraviolet or electron beam decomposable cation accelerator. 6. The adhesive composition according to any one of 1 to 5. 7. The adhesive composition according to claim 1, wherein the solvent (D) is at least one selected from the group consisting of toluene, ethyl acetate, cyclohexane, and n-hexane. 8. An epoxy-modified block further comprising an oil or a plasticizer (E) compatible or soluble in the epoxy-modified block copolymer (A) in the adhesive composition according to claim 1. An adhesive composition which is added in a ratio of 10 parts by weight or less to 100 parts by weight of the total of the copolymer (A) and the tackifier (B). 9. The adhesive composition according to claim 1, further comprising an inorganic filler (F) in an amount of 100% by weight of the epoxy-modified block copolymer (A) and the tackifier (B). An adhesive composition added at a ratio of 50 parts by weight or less to parts by weight. 10. The adhesive composition according to claim 1, further comprising a crosslinking agent (G) in a total amount of 100 parts by weight of the epoxy-modified block copolymer (A) and the tackifier (B). An adhesive composition comprising 1 to 40 parts by weight of the adhesive composition. 11. The adhesive composition according to claim 1, further comprising a lubricant, an antioxidant, a pigment, a dye, an organic filler, a fragrance, an ultraviolet absorber, or a stabilizer. An adhesive composition to which an agent is added. 12. The adhesive composition according to claim 1, which is applied to at least one surface of a substrate and an adherend, and after removing the solvent (D), the substrate and the adherend. And bonding the epoxy-modified block copolymer (A) at a temperature of room temperature to 50 ° C.