KR20160140575A - Adhesive composition for printed wiring board, laminate, and flexible printed wiring board - Google Patents

Abstract

(A), a hydride (B) of an alpha, beta -unsaturated dicarboxylic acid-modified rosin, and an elastomer (C), and the hydride of an alpha, beta -unsaturated dicarboxylic acid-modified rosin (B) has an acid value of 300 to 350 mgKOH / g, and contains 50 to 220 parts by weight based on 100 parts by weight of the alicyclic epoxy compound (A), wherein the elastomer (C) has a glass transition temperature of -35 캜 to 5 캜, Wherein the number of colors in the Hauzen unit is 300 or less.

Description

TECHNICAL FIELD [0001] The present invention relates to an adhesive composition for a printed wiring board, a laminated board and a flexible printed wiring board. BACKGROUND OF THE INVENTION < RTI ID = 0.0 >

The present invention relates to an adhesive composition for a printed wiring board, a laminate and a printed wiring board. More specifically, the present invention relates to an adhesive composition for a printed wiring board, a laminated board and a printed wiring board which can be suitably used as a display substrate such as a substrate for a touch panel, a substrate for an electronic species, a substrate for a flexible display, .

A laminate for a printed wiring board in which a metal foil such as a copper foil is adhered to a plastic film made of polyimide, liquid crystal polymer or the like, which is generally excellent in heat resistance and electrical insulation, is used for the flexible printed wiring board. Flexible printed wiring boards have recently been used for display parts such as displays, and are required to have colorless transparency. In response to such a market demand, a plastic film such as a polyester film such as polyethylene terephthalate (PET) or polyethylene naphthalene (PEN), or a colorless transparent film such as an acrylic film is used as a plastic film as a substrate.

When the plastic film and the metal foil are bonded to each other, an epoxy resin-based adhesive having good adhesive strength is commonly used. The adhesive is generally composed of an epoxy resin, a curing agent and an elastomer, and not only the adhesion with the film but also the flexibility is imparted by curing. The adhesive is applied to a plastic film in the form of a liquid or varnish dissolved in an organic solvent, followed by curing while volatilizing the organic solvent by heating. However, the polyester film and the acrylic film described above are insufficient in heat resistance as compared with the polyimide film and the liquid crystal polymer film, and it is necessary to cure the adhesive at a low temperature. Therefore, the adhesive to be used requires low temperature curability. In order to cure the adhesive at a low temperature, an aliphatic amine-based or aromatic amine-based hardener is used. However, when these amines are used, the adhesive layer tends to be colored during curing.

Further, in order to manufacture the flexible printed wiring board, a circuit is formed from a laminate for a printed wiring board. At that time, an etching liquid is used to partially remove the metal foil layer. In this case, when the low temperature curing of the adhesive and the plastic film becomes insufficient, the uncured portion of the adhesive layer is colored by the etching solution. Therefore, it is necessary that the adhesive not only has adhesiveness but also chemical resistance in addition to low-temperature curing property and colorless transparency.

As a technique for solving these problems, Patent Document 1 discloses that a haze value of the plastic insulating film after containing a polyamide resin, a phenol resin, and an epoxy resin as an adhesive component and removing the copper foil by etching is 5 to 50% A laminate for a flexible printed circuit board has been proposed.

In order to solve the above-described problems, the applicant proposed in Patent Document 2 that a resin composition having a methoxy group-containing silane-modified epoxy resin and a carboxyl group and having a glass transition temperature of 20 占 폚 or lower, an acid value of 2 to 10 (mgKOH / g) There has been proposed an adhesive composition containing a curing agent for an epoxy resin having a molecular weight of 150,000 to 300,000 acrylic polymers (the polymer imparts adhesiveness and flexibility to the film) and an epoxy resin.

Patent Document 1: Japanese Patent Application Laid-Open No. 2003-309336 Patent Document 2: Japanese Patent Application Laid-Open No. 2007-332337

Patent Document 1 discloses a base material which is cured by heating at a temperature of 80 ° C to 180 ° C for 1 to 30 hours. However, the film to which the adhesive is applied is a polyimide film, and a colorless transparent film such as a polyester film or a polyacrylic film is not considered. In addition, the composition described in Patent Document 2 exhibits excellent transparency and adhesiveness as compared with conventional adhesives for printed wiring boards. However, an aromatic amine-based curing agent or a phenol resin-based curing agent is used as a curing agent. Amine-based curing agents tend to cause coloring. Further, the phenol resin-based curing agent is required to be cured at a high temperature of 100 占 폚 or more for a long time, and the low-temperature curing property is not sufficient.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of the prior art, and it is an object of the present invention to provide an adhesive composition for a printed wiring board which satisfies low temperature curability, colorless transparency, adhesiveness and chemical resistance as compared with conventional adhesive compositions for printed wiring boards, And a flexible printed wiring board using the same.

As a result of intensive investigations, the present inventors have found that the above problems can be solved by using an adhesive composition containing a specific amount of a predetermined alicyclic epoxy compound, a rosin hydride and an elastomer, respectively, and completed the present invention .

That is, an adhesive composition for a printed wiring board according to one aspect of the present invention comprises an alicyclic epoxy compound (A), a hydride (B) of an?,? - unsaturated dicarboxylic acid modified rosin, and an elastomer (C) (B) of the α, β-unsaturated dicarboxylic acid-modified rosin has an acid value of 300 to 350 mgKOH / g and is contained in an amount of 50 to 220 parts by weight based on 100 parts by weight of the alicyclic epoxy compound (A) Wherein the elastomer (C) has a glass transition temperature of -35 캜 to 5 캜 and a Hansen unit color number of 300 or less.

A laminated board according to one aspect of the present invention is a laminated board having a plastic film and an adhesive layer for a printed wiring board including the adhesive composition for a printed wiring board formed on the plastic film.

A flexible printed wiring board according to one aspect of the present invention is a flexible printed wiring board including the above laminated board.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide an adhesive composition for a printed wiring board excellent in low temperature curing property, colorless transparency, adhesive property and chemical resistance, a laminate using the adhesive composition for a printed wiring board, and a flexible printed wiring board.

[Adhesive composition for printed wiring board]

Hereinafter, an embodiment of the adhesive composition for a printed wiring board of the present invention (hereinafter also referred to as an adhesive composition) will be described. The adhesive composition of the present embodiment is obtained by mixing an alicyclic epoxy compound (A) (hereinafter also referred to as component (A)) and a hydride of an alpha, beta -unsaturated dicarboxylic acid-modified rosin having an acid value of 300 to 350 mgKOH / g B) (hereinafter also referred to as component (B)) and an elastomer (C) (hereinafter also referred to as component (C)) having a glass transition temperature of -35 占 폚 to 5 占 폚 and having a Hasen color number of 300 or less, do. Each will be described below.

(Alicyclic epoxy compound (A))

The component (A) may be any known one without any particular limitation. For example, the component (A) is at least one of an epoxycyclohexane compound represented by the following formula (1) or a caprolactone adduct thereof in terms of colorless transparency, low temperature curability, and chemical resistance.

(Wherein R ¹ and R ² each represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and X represents an epoxy group-containing substituent)

More specifically, the component (A) may be at least one of an epoxycyclohexane compound represented by the following formula (2) or (3) or a caprolactone adduct thereof.

(Wherein R ¹ to R ⁴ each represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms and ALK denotes an alkylene group having 1 to 4 carbon atoms)

(Wherein R ¹ , R ² and R ⁵ to R ⁷ each represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms)

More specifically, component (A) is selected from the group consisting of bis (3,4-epoxycyclohexyl) oxalate, bis (3,4-epoxycyclohexylmethyl) adipate, bis (3,4-epoxycyclohexylmethyl) piperate, 3,4-epoxycyclohexylmethyl (3,4-epoxy) cyclohexanecarboxylate, 3,4-epoxycyclohexanecarboxylate , 6-methyl-3,4-epoxycyclohexylmethyl (6-methyl-3,4-epoxy) cyclohexanecarboxylate, 3,4-epoxy-2-methylcyclohexylmethyl (3,4- 3-methylcyclohexylcarboxylate, 3,4-epoxy-3-methylcyclohexylmethyl (3,4-epoxy-3-methyl) cyclohexanecarboxylate, (3,4-epoxy-5-methyl) cyclohexanecarboxylate and their caprolactone adducts, limonene dioxide, vinylcyclohexene dioxide and the like. These may be used in combination of two or more. These can all be synthesized by a conventional method. Among them, the component (A) is preferably 3,4-epoxycyclohexylmethyl (3,4-epoxy) cyclohexanecarboxylate (commercially available as " CELLOXIDE 2021P " CELLOXIDE 2081 ", " CELLOXIDE 2083 " (manufactured by Daicel) or limonene dioxide (commercially available as "Limonene Dioxide" (manufactured by RENESSENZ)).

Further, other epoxy resin may be used in combination with the component (A) within a range not deviating from the object and effect of the present embodiment. As the other epoxy resin, various known resins can be used without any particular limitation. Examples of other epoxy resins include glycidyl ether type epoxy resins such as bisphenol A type epoxy resins, bisphenol F type epoxy resins, novolac type epoxy resins and brominated epoxy resins, and heterocyclic epoxy resins. These may be used in combination of two or more. The amount of the other epoxy resin to be used is not particularly limited. Other epoxy resins can generally be used in an amount of less than 30% by weight based on the component (A).

(hydride (B) of?,? -unsaturated dicarboxylic acid-modified rosin)

Component (B) is a hydride obtained by subjecting a rosin, which is a raw material, to an addition reaction of an?,? - unsaturated dicarboxylic acid to a further hydrogenation treatment. The component (B) can be obtained by (I) hydrogenating the α, β-unsaturated dicarboxylic acids and the rosin-based Diels-Alder reactant, (II) (J. Am. Chem. Soc. 70, 334 (1948)) isolated from rosins by a known method and a method of hydrogenating an?,? - unsaturated dicar And a method of hydrogenating a Diels-Alder reaction of a leucyl acid. Among them, the method (I) is industrially simple.

Examples of the rosin as the raw material of the component (B) include rosin, wood rosin, tolun rosin and the like. The purification method of rosins is not particularly limited. The rosin is preferably purified by vacuum distillation, steam distillation, extraction, recrystallization or the like, for reasons such as the color tone of the obtained adhesive composition and the like.

Organic solvents are suitably used for purification. Specifically, the organic solvent includes aromatic hydrocarbons such as benzene, toluene and xylene; Ketones such as acetone and methyl ethyl ketone; aliphatic hydrocarbons such as n-hexane, n-heptane and isooctane; Alicyclic hydrocarbons such as cyclohexane and decalin, and the like. These organic solvents may be used in combination of two or more.

Examples of the?,? - unsaturated dicarboxylic acid include maleic anhydride, maleic acid and fumaric acid. Among them, the?,? - unsaturated dicarboxylic acid is preferably maleic anhydride in view of the stability of the reaction and the yield. The amount of the alpha, beta -unsaturated dicarboxylic acid is generally at least 15 parts by weight, preferably at least 17.5 parts by weight, based on 100 parts by weight of the rosin, in view of the solubility of the resulting component (B) in an organic solvent . The amount of the?,? - unsaturated dicarboxylic acid to be used is generally 25 parts by weight or less, preferably 23.5 parts by weight or less.

Conditions for reacting the rosin with the?,? - unsaturated dicarboxylic acid are not particularly limited. For example, the reaction between the rosin and the α, β-unsaturated dicarboxylic acid is carried out by adding α, β-unsaturated dicarboxylic acid to the rosin, which is generally melted under heating, at a temperature of 180 to 240 ° C. For 1 to 9 hours. Further, the reaction between the rosin and the?,? -Unsaturated dicarboxylic acid is preferably carried out by blowing an inert gas such as nitrogen into the sealed reaction system to improve the color tone of the adhesive composition. For the reaction, known catalysts such as Lewis acids such as zinc chloride, iron chloride and tin chloride and Bronsted acids such as para-toluenesulfonic acid and methanesulfonic acid can be used. The amount of such a catalyst to be used is usually about 0.01 to 10% by weight based on the rosin.

The obtained?,? - unsaturated dicarboxylic acid modified rosin may contain a resin acid derived from the raw material. However, the content of the resin acid derived from the raw material is preferably 40 to 60% by weight from the viewpoint of solubility in an organic solvent.

The component (B) is obtained by hydrogenating the above-mentioned?,? - unsaturated dicarboxylic acid modified rosin by various known methods. Specifically, in the hydrogenation treatment, the α, β-unsaturated dicarboxylic acid-modified rosin is reacted in the presence of a hydrogenation catalyst at a temperature of about 100 to 300 ° C. (preferably 150 to 260 ° C.) and a hydrogen pressure of about 1 to 25 MPa Is 5 to 20 MPa). Examples of the hydrogenation catalyst include supported catalysts such as palladium carbon, rhodium carbon, ruthenium carbon, and platinum carbon; Metal powders such as nickel and platinum; And iodides such as iodine and iron iodide. The amount of the hydrogenation catalyst to be used is usually 0.01% by weight or more, preferably 0.10% by weight or more based on the?,? - unsaturated dicarboxylic acid-modified rosin. The amount of the hydrogenation catalyst to be used is generally about 10.0% by weight or less, preferably 5.0% by weight or less based on the?,? - unsaturated dicarboxylic acid modified rosin. Further, in the hydrogenation treatment, an organic solvent may be used as a solvent if necessary. The obtained component (B) is preferably purified by the aforementioned rosin-based purification method in terms of heat resistance and chemical resistance.

By the hydrogenation treatment, the resin acid derived from the raw material rosin such as abietic acid is simultaneously hydrogenated. Whereby dehydroabietic acid, dihydroabietetic acid, tetrahydroabietic acid and the like are produced. Thus, the resulting component (B) not only has a good color tone but also increases the wettability of the adhesive composition to the adherend and also increases the adhesiveness to the metal foil. Further, the adhesive composition using such component (B) can form a colorless transparent adhesive layer.

The content of the hydride of the resin acid (dehydroabietic acid, dihydroabietetic acid, tetrahydroabietinic acid, etc.) contained in the component (B) is preferably from the viewpoint of solubility in an organic solvent and adhesion to a metal foil And the total amount is preferably 20 to 60% by weight.

The color tone of the obtained component (B) is not particularly limited. From the viewpoint of transparency of the resulting adhesive layer, the color tone of the component (B) is preferably not more than 200, more preferably not more than 150, in terms of the number of Hansen's unit colors (in accordance with JIS K 0071-1) .

The acid value of the component (B) is generally about 300 mgKOH / g or more, preferably 320 mgKOH / g or more. The acid value of the component (B) is generally about 350 mgKOH / g or less, preferably 345 mgKOH / g or less. The component (B) having an acid value is likely to be appropriately dissolved in various organic solvents. Further, the laminate for printed wiring boards obtained by using the adhesive composition of the present embodiment tends to have improved chemical resistance. Further, the acid can be calculated by dissolving the component (B) in a mixed solvent of acetone / potassium hydroxide, and then titrating the phenolphthalein solution with a small amount of the solution with hydrochloric acid (in accordance with JIS K-0070).

The blending amount of the component (B) (in terms of solid content) is preferably at least 50 parts by weight based on 100 parts by weight of the component (A), more preferably at least 60 parts by weight. The blending amount of the component (B) should be 220 parts by weight or less, preferably 210 parts by weight or less, based on 100 parts by weight of the component (A). If it is out of the above range, the component (A) or the component (B) remains in the adhesive layer after the crosslinking reaction, and the chemical resistance tends to be deteriorated. The amount of the component (B) to be added is preferably about 0.1 equivalent or more, more preferably about 0.5 equivalents or more, in terms of the carboxy equivalent (sum of the tertiary carboxyl group and the anhydride) in the component (B) relative to 1 equivalent of the epoxy group present in the component (A) Equivalent or more is more preferable. The blending amount of the component (B) is preferably 2.0 equivalents or less, more preferably 1.5 equivalents or less, based on 1 equivalent of the epoxy group present in the component (A).

(Elastomer (C))

Component (C) is used for imparting flexibility to the adhesive layer after curing and for enhancing adhesion with a plastic film such as polyester.

Component (C) is not particularly limited as long as it has a glass transition temperature (in accordance with JIS K-7244-1) of -35 캜 to 5 캜. The glass transition temperature may be -35 캜 or higher, preferably -30 캜 or higher, and more preferably -25 캜 or higher. The glass transition temperature may be 5 DEG C or lower, preferably -5 DEG C or lower, more preferably -15 DEG C or lower. When the glass transition temperature is less than -35 占 폚, the adhesive composition tends to lack chemical resistance during the etching treatment. If the glass transition temperature is higher than 5 占 폚, the flexibility of the adhesive layer after curing and the adhesion with the plastic film are liable to deteriorate.

The color tone of the component (C) may be 300 or less, preferably 200 or less, more preferably 150 or less in terms of transparency of the resulting adhesive layer.

The component (C) exhibiting the glass transition temperature may be, for example, an acrylic elastomer or a polyurethane elastomer.

When the component (C) is an acrylic elastomer, the component (C) has at least one functional group selected from the group consisting of a carboxyl group and a hydroxyl group. (1) , And (2) a polymer obtained by graft-polymerizing at least one monomer having the functional group with the monomer as the main component. Specifically, the component (C) comprises an epoxy group-containing monomer (c2) (hereinafter referred to as a component (c1)) in a constitutional component containing one of the acrylic acid ester or the? -Substituted acrylate ester (c1) having at least one functional group selected from the group consisting of a carboxyl group-containing monomer (c2)), a carboxyl group-containing monomer (c3) (hereinafter referred to as component (c3)) and a hydroxyl group- And a copolymer obtained by copolymerizing monomers.

Examples of the component (c1) include monomers having no epoxy group, carboxyl group and hydroxyl group such as methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate and octyl acrylate. Examples of the component (c2) include glycidyl ethers such as vinyl glycidyl ether and allyl glycidyl ether, glycidyl acrylate, and glycidyl methacrylate, which do not have a carboxyl group and a hydroxyl group in addition to the component (c1) . Examples of the component (c3) include acrylic acid, methacrylic acid, itaconic acid, maleic acid, and maleic anhydride which do not have a hydroxyl group other than the components (c1) to (c2). As the component (c4), 2-hydroxyethyl methacrylate other than the components (c1) to (c3), 2-hydroxypropyl methacrylate, ethylene glycol dimethacrylate, propylene glycol dimethacrylate, polyethylene Dimethacrylates of polyhydric alcohols such as glycol dimethacrylate, and alkoxy acrylates such as methoxymethyl acrylate. These may be used in combination of two or more. If necessary, other vinyl monomers such as vinyl chloride, vinylidene chloride, styrene, acrylonitrile, vinyl acetate, etc. may be copolymerized.

Examples of the acrylic elastomer of the component (C) to be obtained include polyacrylic acid, polymethacrylic acid, methyl polyacrylate, ethyl polyacrylate, butyl polyacrylate, octyl acrylate, methyl acrylate-styrene copolymer, acrylmethyl acrylonitrile copolymer, Butyl acrylate-acrylonitrile-acrylic acid copolymer, butyl acrylate-ethyl acrylate-acrylonitrile copolymer, and other polyacrylate ester-based copolymers. Among them, the component (C) is preferably a butyl acrylate-ethyl acrylate-acrylonitrile copolymer so that the adhesive composition can be favorably adhered to a plastic film or a metal foil. Examples of commercially available products include TEISANRESIN SG-70L and TEISANRESIN WS-023 EK30 (manufactured by Nagase ChemteX Corporation).

When the component (C) is an acrylic elastomer, the component (C) is preferably contained in an amount of 200 parts by weight or more based on 100 parts by weight of the component (A), more preferably 230 parts by weight or more. The component (C) is preferably contained in an amount of not more than 750 parts by weight based on 100 parts by weight of the component (A), more preferably not more than 710 parts by weight. When the content of the component (C) is less than 200 parts by weight, the adhesive composition tends to deteriorate in adhesiveness. On the other hand, if the content of the component (C) exceeds 750 parts by weight, the chemical resistance of the adhesive composition tends to deteriorate.

When the component (C) is an acrylic elastomer, the number average molecular weight of the component (C) is not particularly limited. For example, the number average molecular weight of the component (C) is about 150,000 to 300,000.

On the other hand, when the component (C) is a polyurethane elastomer, such a component (C) can be obtained, for example, by reacting a high molecular weight polyol (c5) (hereinafter also referred to as component (c5)), a diisocyanate compound (c6)) and chain extender (c7) (hereinafter also referred to as component (c7)).

Component (c5) specifically includes polyether polyols such as polymers or copolymers such as ethylene oxide, propylene oxide, and tetrahydrofuran; Ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, pentanediol, 3- Saturated or unsaturated, various known glycols such as octanediol, 1,4-butynediol, diethylene glycol, triethylene glycol, and dipropylene glycol, or n-butyl glycidyl ether, 2-ethylhexyl glycidyl ether, etc. Monocarboxylic acid glycidyl esters such as alkyl glycidyl ethers of benzoic acid, glycidyl ethers of benzoic acid, and glycidyl esters of Versatic acid, dimer diols obtained by reducing dimer acid and adipic acid, adipic acid, phthalic anhydride, A dibasic acid such as terephthalic acid, maleic acid, fumaric acid, succinic acid, oxalic acid, malonic acid, glutaric acid, pimaric acid, suberic acid, azelaic acid and sebacic acid or a corresponding acid anhydride or dimer acid Polyester polyols; polycaprolactone polyols obtained by ring-opening polymerization of cyclic ester compounds such as? -caprolactone; And other known high molecular polyols which are used in the production of polyurethanes such as polyisocyanates, polyisocyanates, other polycarbonate polyols, polybutadiene glycols, glycols obtained by adding ethylene oxide or propylene oxide to bisphenol A, and the like. Further, the polyether polyester polyol can be obtained by subjecting the polyester polyol to addition polymerization of ethylene oxide, propylene oxide, tetrahydrofuran and the like.

Specific examples of the component (c6) include aromatic, aliphatic and alicyclic diisocyanates. More specifically, component (c6) is selected from the group consisting of 1,5-naphthylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzylisocyanate , Dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, triphenyl diisocyanate, butane-1,4-diisocyanate, hexa Methylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, cyclohexane-1,4-diisocyanate, xylene diisocyanate, isophorone diisocyanate , Dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, methylcyclohexane diisocyanate, dimer diisocyanate And the like. These may be used in appropriate combination of two or more species. Among these, isophorone diisocyanate is preferable from the viewpoint of the colorless transparency of the adhesive layer. In addition, other diisocyanates may be used in combination within the range not deviating from the objects and effects of the present embodiment. As the other diisocyanate, various known ones can be used without any particular limitation. The other diisocyanate may be used in combination with, for example, less than 30% by weight based on the component (c6).

The component (c7) specifically includes polyamides such as ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, isophoronediamine, dicyclohexylmethane-4,4'-diamine, Amines, 2-hydroxyethylethylenediamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypropylethylenediamine, Diamines having a hydroxyl group in the molecule such as hydroxypropylethylenediamine, and the above-mentioned low molecular glycols. These may be used in appropriate combination of two or more species. Among these, isophoronediamine is preferable from the viewpoint of the colorless transparency of the adhesive layer.

A chain extender c8 (hereinafter also referred to as component (c8)) may be added to the reaction components (components (c5) to (c7)) as a raw material of the component (C), if necessary. Specific examples of the component (c8) include dialkylamines such as di-n-butylamine, dihydroxyalkylamines such as diethanolamine, alcohols such as ethanol and isopropyl alcohol, Imidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, Imidazoles, and the like.

In preparing the component (C), an organic solvent (D) (hereinafter also referred to as component (D)) described below may be used without any particular limitation.

The production method of the component (C) is not particularly limited. Component (C) can be prepared, for example, by the following two methods.

(Method 1) Two-step process: A polyol and an excess of a diisocyanate compound are reacted at about 70 to 150 ° C. for about 3 to 10 hours to prepare a prepolymer having an isocyanate group at the end of the polymer polyol, And optionally reacting with a chain extender.

(Method 2) Method: A method of simultaneously reacting a polyol, a diisocyanate compound, a chain extender and, if necessary, a chain extender.

Among the above methods, Method 1 is preferable in order to obtain a uniform polymer solution.

Examples of the component (C) to be obtained include polycarbonate polyurethane, polyether polyester polyurethane, polyether carbonate polyurethane, polycaprolactone polyurethane, aliphatic polyurethane, aromatic polyurethane and the like. Among them, the component (C) is preferably a polyether polyester polyurethane so that the adhesive composition can adhere well to a plastic film or a metal foil. As a commercially available product of polyether polyester polyurethane, TAJ-642 (manufactured by Arakawa Chemical Industries Co., Ltd.) and the like can be mentioned.

When the component (C) is a polyurethane elastomer, the component (C) is preferably contained in an amount of 200 parts by weight or more based on 100 parts by weight of the component (A), more preferably 230 parts by weight or more . The component (C) is preferably contained in an amount of not more than 750 parts by weight based on the component (A), more preferably not more than 710 parts by weight. When the content of the component (C) is less than 200 parts by weight, the adhesive composition tends to deteriorate in adhesiveness. On the other hand, if the content of the component (C) exceeds 750 parts by weight, the chemical resistance of the adhesive composition tends to deteriorate.

The number average molecular weight of the obtained component (C) is preferably 7,500 or more, and more preferably 10,000 or more. The number average molecular weight of the component (C) is preferably 30,000 or less, and more preferably 25,000 or less. With such a number average molecular weight, the component (C) easily dissolves with the component (A) and the component (B), and after the curing, the adhesive property of the adhesive composition to the plastic film or the metal foil tends to be secured.

The component (C) may also be used in combination with another elastomer within the scope of the object and effect of the present embodiment. Specific examples of the other elastomer include acrylic polymer, acrylonitrile butadiene polymer, styrene butadiene polymer, butadiene methyl acrylate acrylonitrile polymer, butadiene polymer, carboxyl group-containing acrylonitrile butadiene polymer, vinyl group-containing acrylonitrile Butadiene polymer, silicone polymer, polyvinyl butyral, polyester, polyimide and the like. These may be used in combination of two or more. The amount of the other elastomer used is generally less than 30% by weight of the component (C).

Returning to the description of the entire adhesive composition, since the adhesive composition of the present embodiment is applied to a plastic film, it preferably contains an organic solvent (hereinafter also referred to as component (D)). Specific examples of the component (D) include alcohols such as methanol, ethanol, isopropanol and n-butanol; Ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; Ethers such as dioxane and tetrahydrofuran; Aliphatic hydrocarbons such as hexane, cyclohexane and methylcyclohexane; Esters such as ethyl acetate and butyl acetate; Aromatic hydrocarbons such as benzene, toluene and xylene; And aprotic polar solvents such as dimethylsulfoxide, N-methyl-2-pyrrolidone and dimethylformamide. These may be used in combination of two or more. Among them, the component (D) is preferably a low-boiling organic solvent having a boiling point of 120 캜 or less in order to cure the adhesive at a low temperature by using a film having a low heat resistance. More specifically, the component (D) is preferably methanol, ethanol, isopropyl alcohol, acetone, methyl ethyl ketone, ethyl acetate, butyl acetate, toluene and the like.

The adhesive composition of the present embodiment may suitably be added with an epoxy curing accelerator within a range not deviating from the objects and effects of the present embodiment. Specific examples of the epoxy curing accelerator include 1,8-diazabicyclo [5.4.0] undecene-7, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris (dimethylaminomethyl) Tertiary amines; Imidazoles such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole and 2-heptadecylimidazole; Organic phosphines such as tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine and phenylphosphine; Tetraphenylboron salts such as tetraphenylphosphonium tetraphenylborate, 2-ethyl-4-methylimidazole tetraphenylborate, and N-methylmorpholine tetraphenylborate. The epoxy curing accelerator is preferably used in a proportion of about 0.05 to 5% by weight based on the total amount of the component (A) and the component (B).

The adhesive composition of the present embodiment may contain a releasing agent, a surface treating agent, a flame retardant, a viscosity adjusting agent, a plasticizer, an antibacterial agent, a fungicide, a leveling agent, a defoaming agent, a colorant, May be blended.

As described above, the adhesive composition of the present embodiment is an adhesive composition comprising the component (A) (alicyclic epoxy compound (A)), the component (B) (acid value is 300 to 350 mgKOH / g, (C) (having a glass transition temperature of -35 DEG C to 5 DEG C and a Hagen unit color number of 300 or less), each of which contains a specific amount of each of the elastomer (B) and the component (C) The adhesive composition of the present embodiment is suitable for a flexible printed wiring board for display use or optical use as compared with an adhesive composition for a wiring board at the same time as a low temperature curing property, a colorless transparency, an adhesive property and a chemical resistance. , The adhesive composition is suitable for a substrate for a touch panel, a substrate for an electronic species, a substrate for a flexible display, a reflective film, a metal mesh film, etc. The adhesive composition can be used for an IC card and an IC tag substrate, It is also suitable for the layered product or the like.

[About adhesive sheet and laminate for printed wiring board]

Hereinafter, as an embodiment of the laminated sheet of the present invention, a laminated sheet for an adhesive sheet and a printed wiring board will be described. The adhesive sheet (one example of the laminate) of the present embodiment is an adhesive sheet provided with a plastic film and an adhesive layer for a printed wiring board containing the adhesive composition for a printed wiring board of the above-described embodiment on a plastic film.

The plastic film is not particularly limited, and any known plastic film may be used without limitation. Specific examples of the plastic film include a polyester film such as polyethylene naphthalate (PEN) and polyethylene terephthalate (PET), an acrylic film, and a cycloolefin polymer film. Among them, the plastic film is preferably a polyester film in terms of balance of colorless transparency and chemical resistance. The thickness of the plastic film may be appropriately set depending on the application.

The method of producing the adhesive sheet is not particularly limited. The adhesive sheet is coated on the plastic film, for example, as a base material with the adhesive composition for printed wiring boards of the above-mentioned embodiment so that the film thickness at the time of curing is about 5 to 50 mu m, and the adhesive sheet is heated at 50 to 120 DEG C for 30 seconds to 5 minutes By preliminary drying.

The adhesive sheet of the present embodiment may be a laminated board in which a metal foil is further provided on the printed wiring board adhesive layer on which the composition for a printed wiring board of the above embodiment is coated. Such a laminate is suitable as a laminate for a printed wiring board. The method of providing the metal foil on the printed wiring board adhesive layer is not particularly limited. For example, the metal foil may be laminated on the printed wiring board adhesive layer (lamination method), deposited (vapor deposition method), or sputtered (sputtering method).

When a metal foil is provided by the lamination method, the laminate for a printed wiring board can be manufactured by, for example, thermally bonding a metal foil to a printed wiring board adhesive layer and laminating the same with a laminate roll heated to about 40 to 120 ° C. In the laminate for a printed wiring board of the present embodiment, an adhesive layer made of the above resin composition is formed. Therefore, the laminate for a printed wiring board can be cured at a low temperature for about 0.5 to 10 days at a temperature of about 40 to 70 DEG C, for example, in a printed wiring board adhesive layer.

The metal foil is not particularly limited and various known ones can be used. Specifically, examples of the metallic foil include gold foil, ITO foil, silver foil, copper foil nichrome foil and aluminum foil. Among them, the metal foil is preferably copper foil because of its excellent conductivity and corrosion resistance in the use of the flexible printed wiring board.

The thus-obtained laminate for a printed wiring board has not only good adhesion but also chemical resistance, and further, by partially removing the metal foil by the etching treatment, excellent permeability can be exhibited.

[About Flexible Printed Circuit Board]

Hereinafter, one embodiment of the flexible printed wiring board of the present invention will be described. The flexible printed wiring board of the present embodiment includes the above-mentioned laminate for a printed wiring board (an example of a laminate board). In the flexible printed wiring board, for example, a metal foil surface of a laminate for a printed wiring board is partially removed by etching to form a circuit. Such a flexible printed wiring board can be suitably used as a substrate for a display such as a substrate for a touch panel, a substrate for an electron species, or a substrate for a flexible display.

The embodiments of the present invention have been described above. The present invention is not particularly limited to the above embodiment. The above-described embodiment mainly describes the invention having the following constitution.

(1) A resin composition comprising (a) an alicyclic epoxy compound, (b) a hydride of an?,? - unsaturated dicarboxylic acid modified rosin, and an elastomer (C), wherein the?,? - unsaturated dicarboxylic acid modified The rosin hydride (B) has an acid value of 300 to 350 mgKOH / g, and contains 50 to 220 parts by weight of the alicyclic epoxy compound (A) per 100 parts by weight of the elastomer (C) 35 占 폚 to 5 占 폚, and the number of colors in the Hauzen unit is 300 or less.

(2) The elastomer (C) is an acrylic elastomer, which is a polyacrylic acid ester copolymer, and contains 200 to 750 parts by weight of the alicyclic epoxy compound (A) per 100 parts by weight of the printed circuit board / RTI >

(3) The adhesive composition for a printed wiring board according to (1), wherein the elastomer (C) is a polyurethane elastomer and contains 200 to 750 parts by weight based on 100 parts by weight of the alicyclic epoxy compound (A).

(4) The adhesive composition for a printed wiring board according to (3), wherein the polyurethane elastomer is a polyether polyester polyurethane.

(5) The method according to any one of (1) to (4), wherein the alicyclic epoxy compound (A) comprises at least one of an epoxycyclohexane compound represented by the following formula (1) or a caprolactone adduct thereof ≪ / RTI >

(Wherein R ¹ and R ² each represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and X represents an epoxy group-containing substituent)

(6) The method according to (5), wherein the alicyclic epoxy compound (A) comprises at least one of 3,4-epoxycyclohexylmethyl (3,4-epoxy) cyclohexanecarboxylate or a caprolactone adduct thereof. By weight of the adhesive composition for a printed wiring board.

(7) The hydrate (B) of the α, β-unsaturated dicarboxylic acid-modified rosin is at least one selected from the group consisting of maleic anhydride, maleic acid and fumaric acid. Wherein the adhesive composition for a printed wiring board described in any one of < 1 >

(8) The adhesive composition for a printed wiring board according to any one of (1) to (7), wherein the hydride (B) of the?,? - unsaturated dicarboxylic acid modified rosin has a number of hue unit color of 200 or less.

(9) The adhesive composition for a printed wiring board according to any one of (1) to (8), further comprising an organic solvent (D).

(10) The adhesive composition for a printed wiring board according to (9), wherein the organic solvent (D) is an organic solvent having a boiling point of 120 ° C or lower.

(11) A laminate comprising a plastic film and an adhesive layer for a printed wiring board comprising the plastic film and the adhesive composition for a printed wiring board according to any one of (1) to (10).

(12) The laminate according to (11), wherein a metal foil is further bonded to the adhesive layer for a printed wiring board.

(13) The laminate according to the above (11) or (12), which is for a printed wiring board.

(14) A flexible printed wiring board comprising the laminate according to any one of (11) to (13).

Example

Hereinafter, the present invention will be described in detail with reference to examples and comparative examples. The present invention is not limited to these embodiments.

The raw materials used are as follows.

≪ Epoxy resin &

(Component (A): Alicyclic epoxy compound (A))

A-1: 3,4-epoxycyclohexylmethyl (3,4-epoxy) cyclohexanecarboxylate (trade name: CELLOXIDE 2021P, manufactured by Daicel Co., Ltd.)

A-2: Caprolactone adduct of A-1 ("CELLOXIDE 2081", manufactured by Daicel Co., Ltd.)

A-3: Limonene dioxide (trade name: Limonene Dioxide, manufactured by RENESSENZ, the structure of which is shown below)

(Other epoxy resin)

JER: bisphenol A type epoxy resin (trade name " JER828 ", manufactured by Mitsubishi Chemical Corporation)

YDPN: phenol novolak type epoxy resin (trade name "YDPN-638", manufactured by Nippon Steel Sumitomo Metal Co., Ltd.)

<Curing agent>

(Component (B): hydride (B) of?,? - unsaturated dicarboxylic acid modified rosin having an acid value of 300 to 350 mgKOH / g)

B-1: Maleinophosphoric acid hydride (acid value: 330 mgKOH / g, color tone:

B-2: Maleinophosphoric acid hydride (acid value: 316 mgKOH / g, color tone: Haagen color number 150)

(Other curing agent)

B-3: Maleinophosphoric acid hydride (acid value: 358 mgKOH / g, color tone:

B-4: Maleinophosphoric acid hydride (acid value: 270 mgKOH / g, color tone:

RIKACID: liquid phase alicyclic acid anhydride (trade name: &quot; RIKACID MH-700 &quot;, manufactured by Shin-Etsu Chemical Co., Ltd., color tone:

TAMANOL: Phenol novolak resin (TAMANOL 759, manufactured by Arakawa Chemical Industries, Ltd., color tone: Gardner color number 3)

b2: Maleylated rosin obtained in the step (2) of Preparation Example 1

GASKAMIN: An additional reaction product of metaxylenediamine and styrene (trade name "GASKAMIN 240", manufactured by Mitsubishi Gas Chemical Co., Ltd., color tone:

<Elastomer>

(Component (C): an elastomer (C) having a glass transition temperature of -35 to 5 占 폚 and a Hasen color number of 300 or less)

C-1: Polyether polyester polyurethane (trade name: TAJ-642, manufactured by Arakawa Chemical Industries, Ltd., solid content: 35% (ethyl acetate / IPA), glass transition temperature: ))

C-2: Acrylic acid ester copolymer (trade name: "TEISANRESIN SG-70L", concentration 12.5%, glass transition temperature: -17 ° C, color tone:

C-3: Acrylic acid ester copolymer (trade name: TEISANRESIN WS-023 EK30, concentration 30%, glass transition temperature: -10 占 폚, color tone:

(Other elastomer)

E-1: Polyether polyester polyurethane (TSP-2548, 30% (ethyl acetate / IPA), glass transition temperature: -30 占 폚, color tone: Gardner color number 3; Arakawa Chemical Industries,

E-2: Polyether polyurethane (trade name: "PU-419L", product of Arakawa Chemical Industries, Ltd., solid content 30% (methyl ethyl ketone / IPA), glass transition temperature:

E-3: Polyester polyurethane (trade name: PU-536, solid content 30% (toluene / IPA), glass transition temperature: -40 캜, color tone: Haagen color number 150, manufactured by Arakawa Chemical Industries,

E-4: Acrylic acid ester copolymer (trade name: Teisanresin SG-P3, concentration 15% (MEK), glass transition temperature: 15 캜, color tone:

E-5: Acrylic acid ester copolymer (trade name: TEISANRESIN SG-600TEA, concentration 15% (toluene / ethyl acetate), glass transition temperature: -37 占 폚, color tone:

E-6: Acrylic acid ester copolymer (trade name: TEISANRESIN SG-708-6, concentration 20% (MEK), glass transition temperature: 6 캜, color tone:

NBR: Carboxy NBR (trade name "XER-32C", color tone: Gardner color number 10, manufactured by JSR Corporation)

&Lt; Preparation of Component (B) >

The production method of the above-mentioned component (B) (B-1 to B-4) is shown below.

(Preparation Example 1: B-1)

Process (1): Purification

The purified rosin (b1) (having an acid value of 177 mgKOH / g and a Gardner color number of 3 (3) was distilled under a reduced pressure of 0.4 kPa under a nitrogen blanket by introducing unrefined chromophores (acid value 171 mgKOH / g, Gardner color number 6, ).

Step (2): Diels-Alder reaction

Subsequently, 700 g of the purified rosin (b1) and 154 g of maleic anhydride were introduced into another distillation column and reacted at 220 DEG C for 4 hours while stirring under a nitrogen stream. Then, unreacted material was removed under a reduced pressure of 4 kPa to obtain maleinized rosin (b2) (Acid value: 335 mgKOH / g, Gardner color number: 8).

Step (3): Hydrogenation reaction

Then, 500 g of maleinophosphine (b2) and 6.0 g of 5% palladium carbon (water content 50%) as a catalyst were introduced into a 1 liter rotary autoclave, oxygen in the system was removed, the pressure was increased to 10 MPa with hydrogen, And hydrogenation was carried out at the above temperature for 3 hours to obtain an unpurified rosin product (b3).

Step (4): Purification

Subsequently, 400 g of the unpurified rosin product (b3) and 200 g of xylene were introduced into a reaction vessel, dissolved under heating, and then subjected to catalytic filtration. Thereafter, xylene was distilled to obtain B-1. Table 1 shows the physical properties of B-1.

(Production Example 2-4: B-2 to B-4)

B-2 to B-4 were obtained in the same manner as in Production Example 1, except that the amount of maleic anhydride used in the step (2) of Production Example 1 was changed as shown in Table 1. Table 1 shows the physical properties of B-2 to B-4.

Production Example 1 Production Example 2 Production Example 3 Production Example 4 Resin number B-1 B-2 B-3 B-4 Gum rouge (g) 700 700 700 700 Maleic anhydride (g) 154 123 187 77 Acid value
(mgKOH / g) 330 316 358 270 hue
(Hagen color number) 150 150 200 150

&Lt; Preparation of adhesive composition >

(Example 1)

100.0 g of the epoxy resin A-1, 139.0 g of the curing agent B-1, 1604.0 g of the elastomer C-1 (solid content: 561.4 g) and 139.0 g of methyl ethyl ketone were mixed and uniformly dissolved to prepare an adhesive composition. The carboxyl group in the epoxy resin A-1 is equivalent to one equivalent of the epoxy group present in the adhesive composition.

(Examples 2 to 12 and Comparative Examples 1 to 20)

An adhesive composition was prepared in the same manner as in Example 1, except that the epoxy resin, the curing agent and the elastomer used were changed to those shown in Table 2.

&Lt; Preparation of adhesive sheet &

The adhesive composition obtained in Examples 1 to 12 and Comparative Examples 1 to 20 was applied to a polyester film (COSMOSHINE A 4100, trade name, manufactured by TOYOBO CO., LTD.) With a roll coater and coated so as to have a thickness of 12 μm And preliminarily dried in a drier at 90 캜 for 3 minutes to obtain an adhesive sheet.

&Lt; Production of laminate for printed wiring board &

The adhesive layer of the adhesive sheet obtained using the adhesive composition obtained in Examples 1 to 12 and Comparative Examples 1 to 20 and the mirror surface of a copper foil of 18 mu m (trade name "F2-WS", manufactured by Furukawa Circuit Foil Co., Ltd.) And pressed with a laminating roll at 100 ° C. Thereafter, the adhesive layer was cured by heating in an oven at 60 DEG C for 4 days to obtain a laminate for a printed wiring board. The peel strength, chemical resistance and transparency of the resulting laminate for a printed wiring board were measured under the following conditions. The results are shown in Table 2.

(Peel strength)

The peel strength of the copper foil and the plastic film was measured according to JIS C-6481. The higher the value, the better the peel strength.

(Chemical resistance)

The test piece of the laminate for printed wiring boards was immersed in an etching solution (40% aqueous solution of ferric chloride) at room temperature for 1 hour to dissolve the copper foil, and the b * value was measured in the colorimeter. The smaller the value of b *, the higher the chemical resistance.

(Transparency)

The test piece of the laminate for printed wiring boards was immersed in an aqueous solution of 40% ferric chloride for 1 hour at room temperature to dissolve the copper foil, and haze (haze) (according to JIS K 7105) was measured with a haze meter. The smaller the number, the higher the transparency.

[Table 2]

As shown in Table 2, the adhesive compositions of Examples 1 to 12 were found to be cured at a low temperature of 60 占 폚 for 4 days. Further, the laminate for printed wiring boards obtained by using the adhesive compositions of Examples 1 to 12 was found to have not only excellent peel strength but also excellent chemical resistance and transparency of the adhesive layer.

<Production of Flexible Printed Circuit Board>

A copper wiring having a line / space of 50 m / 50 m was formed by removing a part of the copper foil by etching treatment using an etching solution (an aqueous solution of 40% ferric chloride) to the obtained printed wiring board laminates to produce a flexible printed wiring board Confirmed.

Claims (14)

(A), a hydride (B) of an?,? - unsaturated dicarboxylic acid modified rosin and an elastomer (C), wherein the alicyclic epoxy compound
The hydride (B) of the?,? - unsaturated dicarboxylic acid modified rosin has an acid value of 300 to 350 mgKOH / g and 50 to 220 parts by weight of 100 parts by weight of the alicyclic epoxy compound (A)
The elastomer (C)
A glass transition temperature of -35 캜 to 5 캜,
Wherein the number of colors in the Hauzen unit is 300 or less.
The method according to claim 1,
The elastomer (C) is an acrylic elastomer,
A polyacrylic acid ester-based copolymer,
And 200 to 750 parts by weight based on 100 parts by weight of the alicyclic epoxy compound (A).
The method according to claim 1,
Wherein the elastomer (C) is a polyurethane elastomer and comprises 200 to 750 parts by weight based on 100 parts by weight of the alicyclic epoxy compound (A).
The method of claim 3,
Wherein the polyurethane elastomer is a polyether polyester polyurethane.
The method according to any one of claims 1 to 4,
Wherein the alicyclic epoxy compound (A) comprises at least one of an epoxycyclohexane compound represented by the following formula (1) or a caprolactone adduct thereof.
[Chemical Formula 1]

(One)
(Wherein R ¹ and R ² each represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and X represents an epoxy group-containing substituent)
The method of claim 5,
Wherein the alicyclic epoxy compound (A) comprises at least one of 3,4-epoxycyclohexylmethyl (3,4-epoxy) cyclohexanecarboxylate or a caprolactone adduct thereof.
The method according to any one of claims 1 to 6,
Wherein the hydride (B) of the?,? - unsaturated dicarboxylic acid modified rosin is at least one selected from the group consisting of maleic anhydride, maleic acid and fumaric acid.
The method according to any one of claims 1 to 7,
The hydride (B) of the?,? - unsaturated dicarboxylic acid modified rosin has a number of hue unit color of 200 or less.
The method according to any one of claims 1 to 8,
An adhesive composition for a printed wiring board, which further comprises an organic solvent (D).
The method of claim 9,
Wherein the organic solvent (D) is an organic solvent having a boiling point of 120 ° C or less.
A plastic film,
An adhesive layer for a printed wiring board comprising the adhesive composition for a printed wiring board according to any one of claims 1 to 10 is formed on the plastic film.
The method of claim 11,
And a metal foil is further bonded to the adhesive layer for a printed wiring board.
The method according to claim 11 or 12,
Wherein the laminate is a printed wiring board.
A flexible printed wiring board comprising the laminate according to any one of claims 11 to 13.