WO2010071107A1

WO2010071107A1 - Thermosetting modified polyamide resin composition

Info

Publication number: WO2010071107A1
Application number: PCT/JP2009/070825
Authority: WO
Inventors: 慶太高橋; 村上　徹; 修池上; 亮一高澤
Original assignee: 宇部興産株式会社
Priority date: 2008-12-15
Filing date: 2009-12-14
Publication date: 2010-06-24
Also published as: TW201030061A

Abstract

The modified polyamide resin composition contains a modified polyamide resin, into which soft segments made of polybutadiene segments or polycarbonate segments are introduced, and a guanamine resin. When the modified polyamide resin composition is thermally treated, a cured film with excellent electric insulating properties, heat resistance, and flexibility as well as improved surface hardness, tackiness, and warping can be obtained.

Description

Thermosetting modified polyimide resin composition

The present invention relates to a modified polyimide resin composition and a cured film thereof. The cured film obtained by heat-treating this modified polyimide resin composition can be suitably used as an insulating film (protective film) for the flexible wiring board.

Patent Document 1 describes a modified polyimide resin into which a soft segment made of a polycarbonate segment or a polybutadiene segment is introduced.

Patent Document 2 describes a modified polyimide resin into which a soft segment composed of a polybutadiene segment is introduced and a thermosetting composition composed of the modified polyimide resin.

Patent Document 3 describes a modified polyimide resin into which a soft segment composed of a polycarbonate segment is introduced and a thermosetting composition composed of the modified polyimide resin.

In these thermosetting compositions, epoxy resins and / or polyisocyanate compounds are used as components responsible for the curing reaction, but the resulting cured film has a surface hardness and tackiness due to the soft segment. In some cases, there was room for improvement. Furthermore, when it was going to obtain a cured film with high surface hardness using these thermosetting compositions, there existed a problem that it was difficult to suppress the curvature accompanying heat hardening.

Also, for example, when used as an insulating film of a flexible substrate, bending resistance is required. Therefore, a cured film made of these compositions requires a high level of bending resistance as well as sufficient surface hardness.

Japanese Patent Laid-Open No. 7-113004 JP 2006-104462 A JP 2006-307183 A

An object of the present invention is to provide a thermosetting modified polyimide resin composition including a modified polyimide resin into which a soft segment composed of a polybutadiene segment or a polycarbonate segment is introduced. It is an object of the present invention to provide a thermosetting modified polyimide resin composition that can improve tackiness and can suitably suppress warpage that occurs with heat curing. The cured film obtained by heat-treating this thermosetting modified polyimide resin composition is excellent in electrical insulation, heat resistance, flexibility, etc., and particularly improved in surface hardness, tackiness, and warpage. It can be suitably used as an insulating film for flexible wiring boards.

Furthermore, an object of one embodiment of the present invention is to provide a thermosetting modified polyimide resin composition capable of improving the folding resistance of a cured film obtained by heat treatment. The cured film obtained by heat-treating this thermosetting modified polyimide resin composition is excellent in electrical insulation, heat resistance, flexibility, etc., and particularly has improved folding resistance in addition to surface hardness. It can be suitably used as an insulating film for flexible wiring boards.

As a result of various studies, the present inventors have found that a thermosetting modified polyimide resin composition comprising a modified polyimide resin into which a soft segment composed of a polybutadiene segment or a polycarbonate segment has been introduced, is cured together with the modified polyimide resin. The present inventors have found that the surface hardness, tackiness, and warpage of a cured film obtained by heat treatment are improved by using a guanamine resin as a component responsible for the reaction.

Furthermore, the present inventors performed heat treatment by adding acrylic resin beads in a modified polyimide resin composition configured to include a modified polyimide resin into which a soft segment composed of a polybutadiene segment or a polycarbonate segment is introduced. It has been found that the surface hardness of the resulting cured film can be improved and the folding resistance can also be improved.

The present invention relates to a modified polyimide resin composition comprising a modified polyimide resin into which a soft segment composed of a polybutadiene segment or a polycarbonate segment is introduced, and a guanamine resin.

Moreover, one aspect of the present invention relates to a modified polyimide resin composition further containing acrylic beads.

According to the present invention, in a modified polyimide resin composition comprising a modified polyimide resin introduced with a soft segment comprising a polybutadiene segment or a polycarbonate segment, the surface hardness of the cured film obtained by heat treatment, tackiness, and A modified polyimide resin composition with improved warpage can be provided. The cured film obtained by heat-treating this modified polyimide resin composition is excellent in electrical insulation, heat resistance, flexibility and the like, and particularly has improved surface hardness, tackiness and warpage. It can be suitably used as insulation for wiring boards.

Furthermore, according to the embodiment containing acrylic resin beads, it is possible to provide a modified polyimide resin composition that can improve surface hardness and fold resistance. The cured film obtained by heat-treating this modified polyimide resin composition has improved folding resistance and can be suitably used as an insulating film for flexible wiring boards.

This application discloses a first aspect containing a guanamine resin and a second aspect containing acrylic resin beads.

The first aspect disclosed in the present application is summarized as follows.
(1) A modified polyimide resin composition comprising a modified polyimide resin into which a soft segment composed of a polybutadiene segment or a polycarbonate segment is introduced, and a guanamine resin.
(2) The modified polyimide resin composition according to item (1), further comprising an epoxy resin.
(3) The modified polyimide resin composition as described in (1) or (2) above, wherein 1 to 60 parts by mass of guanamine resin is contained per 100 parts by mass of the modified polyimide resin.
(4) The modified polyimide resin composition as described in any one of (1) to (3) above, wherein the guanamine resin is a condensate of benzoguanamine and formaldehyde.
(5) A cured film obtained by heat-treating the modified polyimide resin composition according to any one of items (1) to (4).

Further, the second aspect disclosed by the present application is summarized as follows.
(1) A modified polyimide resin composition comprising an acrylic resin bead in a modified polyimide resin composition comprising a modified polyimide resin into which a soft segment comprising a polybutadiene segment or a polycarbonate segment is introduced.

(2) The item described above, wherein the acrylic resin beads are contained in an amount of 10 to 80 parts by weight, preferably 20 to 60 parts by weight, more preferably 20 to 40 parts by weight with respect to 100 parts by weight of the modified polyimide resin. The modified polyimide resin composition as described in (1).

(3) The modified polyimide resin composition as described in (1) or (2) above, wherein the acrylic resin beads have an average particle size of 10 μm or less, preferably 5 μm or less.

(4) Further comprising at least one curable compound selected from the group consisting of an epoxy compound, a polyvalent isocyanate compound, and an amino resin, according to any one of the above items (1) to (3), The modified polyimide resin composition as described.

(5) A cured film obtained by heat-treating the modified polyimide resin composition according to any one of (1) to (4).

According to the invention of the second aspect, the surface hardness of the cured film obtained by heat treatment in the modified polyimide resin solution composition comprising a modified polyimide resin into which a soft segment made of a polybutadiene segment or a polycarbonate segment is introduced. And the modified polyimide resin composition which can improve folding resistance can be provided. The cured film obtained by heat-treating this modified polyimide resin composition is excellent in electrical insulation, heat resistance, flexibility and the like, and in particular, has improved surface hardness and fold resistance. It can be suitably used as an insulating film.

The first aspect and the second aspect disclosed in the present application can constitute the invention independently as described below. However, both effects can be obtained by simultaneously satisfying the definition of the first aspect and the definition of the second aspect. In the second aspect of the present invention, the first aspect is preferably satisfied, that is, preferably contains a guanamine resin, and further satisfies the provisions of the items (2) to (4) of the first aspect. Furthermore, it is preferable to satisfy the items described for the first aspect in the following description.

First, the first aspect of the present invention will be described.

The modified polyimide resin of the present invention is a modified polyimide resin in which a soft segment composed of a polybutadiene segment or a polycarbonate segment is introduced into a hard segment having an imide structure. The modified polyimide resin is not particularly limited as long as it has both the hard segment and the soft segment. For example, as described in Patent Document 1, it can be obtained by preparing a prepolymer having a terminal isocyanate group from diol and diisocyanate, and reacting the prepolymer with an aromatic tetracarboxylic acid component. Moreover, as described in Patent Documents 2 and 3, an alcoholic hydroxyl-terminated imide oligomer is prepared in advance, and obtained by reacting the alcoholic hydroxyl-terminated imide oligomer, polybutadiene diol or polycarbonate diol, and diisocyanate. Can do. The latter is more preferable because the resulting modified polyimide resin has better solubility and heat resistance.

A feature of the present invention is a modified polyimide resin composition comprising a modified polyimide resin into which a soft segment composed of a polybutadiene segment or a polycarbonate segment prepared as described above is introduced, and is cured together with the modified polyimide resin. By using guanamine resin as a component responsible for the reaction, the surface hardness, tackiness, and warpage of the cured film obtained by heat treatment are improved.

Hereinafter, the case of a modified polyimide resin prepared using an alcoholic hydroxyl-terminated imide oligomer will be described, but the present invention is not limited to the modified polyimide resin thus prepared.

The modified polyimide resin is preferably obtained by reacting a diisocyanate compound, polybutadiene diol or polycarbonate diol, and an alcoholic hydroxyl-terminated imide oligomer represented by the following chemical formula (1).

In the formula, R represents a divalent hydrocarbon group, X represents a tetravalent group excluding the carboxyl group of tetracarboxylic acid, Y represents a divalent group excluding the amino group of diamine, and m represents It is an integer from 0 to 50.

The diisocyanate compound may be any compound as long as it has two isocyanate groups in one molecule. For example, an aliphatic, alicyclic or aromatic diisocyanate, preferably an aliphatic, alicyclic or aromatic diisocyanate having 2 to 30 carbon atoms excluding an isocyanate group, specifically 1,4- Tetramethylene diisocyanate, 1,5-pentamethylene diisocyanate, 1,6-hexamethylene diisocyanate, 2,2,4-trimethyl-1,6-hexamethylene diisocyanate, lysine diisocyanate, 3-isocyanate methyl-3,5,5 -Trimethylcyclohexyl isocyanate (isophorone diisocyanate), 1,3-bis (isocyanate methyl) -cyclohexane, 4,4'-dicyclohexylmethane diisocyanate, tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,5-naphth Diisocyanate, tolidine diisocyanate, can be mentioned xylylene diisocyanate and the like. Moreover, the said diisocyanate compound can use suitably the block diisocyanate which blocked the isocyanate group with the blocking agent.

The polybutadiene diol preferably has a number average molecular weight of 500 to 10,000, more preferably 1,000 to 5,000. When the number average molecular weight is less than 500, it is difficult to obtain suitable flexibility, and when the number average molecular weight exceeds 10,000, the heat resistance and solvent resistance may be deteriorated. In the present invention, the polybutadiene diol may have a double bond in the molecule or may be a hydrogenated double bond in the molecule, but the double bond remains in the molecule. A hydrogenated polybutadiene diol in which a double bond in the molecule is hydrogenated is preferable because it may cause a crosslinking reaction and lose flexibility. Preferred examples of the polybutadiene diol used in the present invention include GI-1000 and GI-2000 manufactured by Nippon Soda Co., Ltd., R-45EPI manufactured by Idemitsu Petrochemical Co., Ltd., and Polytail H manufactured by Mitsubishi Chemical Co., Ltd. it can.

The polycarbonate diol preferably has a number average molecular weight of 500 to 10,000, more preferably 1,000 to 5,000. When the number average molecular weight is less than 500, it is difficult to obtain suitable flexibility, and when the number average molecular weight exceeds 10,000, the heat resistance and solvent resistance may be deteriorated. The polycarbonate diol used in the present invention includes UH-CARB, UD-CARB, UC-CARB, manufactured by Ube Industries, Ltd., PLACEL CD-PL, PLACEL CD-H, manufactured by Daicel Chemical Industries, Ltd., and Kuraray Co., Ltd. The Kuraray polyol C series made by the company etc. can be illustrated suitably. These polybutadiene diols and polycarbonate diols are used alone or in combination of two or more.

The alcoholic hydroxyl group-terminated imide oligomer represented by the chemical formula (1) is obtained from a tetracarboxylic acid component and an amine component composed of a diamine compound and a monoamine compound having one alcoholic hydroxyl group. In the above formula, m represents an integer of 0 to 50, preferably 0 to 20, more preferably 0 to 10, particularly 1 to 5. When m is 50 or more, it takes time to dissolve, or the flexibility of the resulting cured film is inferior.

As the tetracarboxylic acid component, aromatic tetracarboxylic acids, or acid dianhydrides or esterified products of lower alcohols thereof are suitable, and 2,3,3 ′, 4′-biphenyltetracarboxylic acid, 3,3 ', 4,4'-biphenyltetracarboxylic acid, 2,2', 3,3'-biphenyltetracarboxylic acid, 3,3 ', 4,4'-diphenyl ether tetracarboxylic acid, 3,3', 4,4 '-Diphenylsulfonetetracarboxylic acid, 3,3', 4,4'-benzophenonetetracarboxylic acid, 2,2-bis (3,4-benzenedicarboxylic acid) hexafluoropropane, pyromellitic acid, 1,4-bis (3,4-benzenedicarboxylic acid) benzene, 2,2-bis [4- (3,4-phenoxydicarboxylic acid) phenyl] propane, 2,3,6,7-naphtha Tetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 1,2,4,5-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 1,1-bis ( Preferable examples include aromatic tetracarboxylic acids such as 2,3-dicarboxyphenyl) ethane, or acid dianhydrides and esterified products of lower alcohols. Examples of the tetracarboxylic acid component include fats such as cyclopentanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, and 3-methyl-4-cyclohexene-1,2,4,5-tetracarboxylic acid. Cyclic tetracarboxylic acids or acid dianhydrides or esterified products of lower alcohols can also be used.

As the diamine compound, aromatic, alicyclic and aliphatic diamines can be used. Specifically, as the aromatic diamine, one benzene such as 1,4-diaminobenzene, 1,3-diaminobenzene, 2,4-diaminotoluene, 1,4-diamino-2,5-dihalogenobenzene is used. Containing diamines, bis (4-aminophenyl) ether, bis (3-aminophenyl) ether, bis (4-aminophenyl) sulfone, bis (3-aminophenyl) sulfone, bis (4-aminophenyl) methane Bis (3-aminophenyl) methane, bis (4-aminophenyl) sulfide, bis (3-aminophenyl) sulfide, 2,2-bis (4-aminophenyl) propane, 2,2-bis (3-amino) Phenyl) propane, 2,2-bis (4-aminophenyl) hexafluoropropane, o-dianisidine, o-tolidine, tolidine Diamines containing two benzenes such as sulfonic acids, 1,4-bis (4-aminophenoxy) benzene, 1,4-bis (3-aminophenoxy) benzene, 1,4-bis (4-aminophenyl) benzene 1,4-bis (3-aminophenyl) benzene, α, α'-bis (4-aminophenyl) -1,4-diisopropylbenzene, α, α'-bis (4-aminophenyl) -1,3 Diamines containing three benzenes such as diisopropylbenzene, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane 2,2-bis [4- (4-aminophenoxy) phenyl] sulfone, 4,4 ′-(4-aminophenoxy) biphenyl, 9,9-bis (4-amino) Nopyl) fluorene, diamines containing 4 or more benzenes such as 5,10-bis (4-aminophenyl) anthracene, and the like, and cycloaliphatic diamines include isophorone diamine, norbornene diamine, 1,2-diaminocyclohexane, 1,3 Examples of aliphatic diamines such as -diaminocyclohexane, 1,4-diaminocyclohexane and 4,4'-methylenebis (cyclohexylamine) include hexamethylenediamine and diaminododecane. Among these, alicyclic diamines are particularly suitable because they can provide an alcoholic hydroxyl-terminated imide oligomer having both heat resistance and solubility.

The monoamine compound having one alcoholic hydroxyl group is a hydrocarbon compound having one alcoholic hydroxyl group and one amino group in the molecule, and preferably has a carbon number such as aminoethanol, aminopropanol, and aminobutanol. Examples thereof include an aliphatic monoamine compound having 1 to 10 alcoholic hydroxyl groups and an alicyclic monoamine compound having an alcoholic hydroxyl group having 3 to 20 carbon atoms such as aminocyclohexanol.

The alcoholic hydroxyl-terminated imide oligomer comprises a tetracarboxylic acid component and an amine component composed of a diamine compound and a monoamine compound having one hydroxyl group, an acid anhydride group (or two adjacent carboxyl groups, etc.) of the tetracarboxylic acid component. ) And the number of equivalents of the amino group of the amine component so as to be approximately equal to each other, polymerization and imidization reaction can be performed in an organic solvent. Specifically, a tetracarboxylic acid component (particularly tetracarboxylic dianhydride), an amine component composed of a diamine compound and a monoamine compound having a hydroxyl group, an acid anhydride group (or an adjacent dicarboxylic acid group) and an amine component. The oligomer having an amide-acid bond is obtained by reacting each component in an organic polar solvent at a reaction temperature of about 100 ° C. or lower, particularly 80 ° C. or lower, in such a proportion that the amino group of Then, the amide-acid oligomer (also called amic acid oligomer) is added with an imidizing agent at a low temperature of about 0 ° C. to 140 ° C. or heated at a high temperature of 140 ° C. to 250 ° C. It can be obtained by the method of making it. In the dehydration / imidation reaction, toluene or xylene may be added and reacted while removing condensed water by azeotropy.

Examples of the organic solvent used for producing the alcoholic hydroxyl-terminated imide oligomer include amides such as N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, and N-methylcaprolactam. Solvents, solvents containing sulfur atoms such as dimethyl sulfoxide, hexamethylphosphamide, dimethyl sulfone, tetramethylene sulfone, dimethyltetramethylene sulfone, phenol solvents such as cresol, phenol, xylenol, diethylene glycol dimethyl ether (diglyme), triethylene glycol Diglyme solvents such as dimethyl ether (triglyme) and tetraglyme, lactone solvents such as γ-butyrolactone, isophorone, cyclohexanone, 3,3,5-trime Ketones solvents such as Le cyclohexanone, pyridine, ethylene glycol, dioxane, and the like tetramethylurea.

The alcoholic hydroxyl-terminated imide oligomer produced as described above may be a mixture of a plurality of oligomers having different m in the chemical formula (1). In the present invention, a mixture composed of a plurality of imide oligomers having different m may be used separately for each imide oligomer, but can be suitably used as it is without separation. In addition, m (average value of m in the case of a mixture) of the bifunctional hydroxyl-terminated imide oligomer can be controlled by the charging ratio (molar ratio) of the diamine compound and the monoamine compound in the amine component at the time of production.

In the modified polyimide resin, a diisocyanate compound, a polybutadiene diol or a polycarbonate diol, and an alcoholic hydroxyl group-terminated imide oligomer may be reacted at the same time. Preferably, the diisocyanate compound and the polybutadiene diol or the polycarbonate diol are converted into a hydroxyl group. It can react suitably so that it may become an excess amount, and it can obtain suitably by making a terminal isocyanate compound react, and then making an alcoholic hydroxyl group terminal imide oligomer react with the said terminal isocyanate compound. These reactions can be carried out without solvent or in an organic solvent, usually at a reaction temperature of 30 ° C. to 150 ° C., for a reaction time of 1 to 10 hours, preferably in an inert atmosphere. As the organic solvent, a solvent used for producing the above-mentioned alcoholic hydroxyl group-terminated imide oligomer can be preferably used. Details of the modified polyimide resin are as described in more detail in Patent Documents 1 to 3.

In the modified polyimide resin of the present invention, a modified polyimide resin composition may be obtained by replacing a part of polybutadiene diol or polycarbonate diol (usually about 5 to 40 mol% in the diol component) with a reactive polar group-containing diol. Is suitable for curing by heating. As the reactive polar group-containing diol, a diol compound having an active hydrogen as a substituent, for example, a diol compound having a carboxyl group or a phenolic hydroxyl group is preferable, and the number of carbons having a carboxyl group or a phenolic hydroxyl group as a substituent is particularly preferred. A diol compound having 1 to 30 carbon atoms and 2 to 20 carbon atoms is preferred. Specifically, examples of the diol compound having a carboxyl group include 2,2-bis (hydroxymethyl) propionic acid and 2,2-bis (hydroxymethyl) butyric acid. Examples of the diol compound having a phenolic hydroxyl group include 2,6-bis (hydroxymethyl) -phenol and 2,6-bis (hydroxymethyl) -p-cresol.

The modified polyimide resin composition of the present invention comprises at least 100 parts by weight of a modified polyimide resin into which a soft segment comprising (A component) polybutadiene segment or polycarbonate segment is introduced, and (B component) 1 to 60 parts by weight of guanamine resin, preferably 1 to 50 parts by mass, more preferably 3 to 40 parts by mass, particularly preferably 3 to 30 parts by mass, and an organic solvent.

(Component B) The guanamine resin is a component responsible for the curing reaction of the modified polyimide resin composition of the present invention. If the content of the guanamine resin is less than the above range, the effect of the present invention cannot be obtained. If the content exceeds the above range, the modified polyimide resin into which the soft segment composed of the polybutadiene segment or the polycarbonate segment is introduced has excellent characteristics. Insulation, heat resistance, flexibility, etc. may be reduced.

In the modified polyimide resin composition of the present invention, 0.1 to 30 parts by mass, preferably 0.1 to 20 parts by mass, more preferably 0, of (C component) epoxy resin as a component responsible for the curing reaction. It is preferable to contain 5 to 10 parts by mass since the low-temperature curability can be improved.

As the guanamine resin, a benzoguanamine resin which is a condensate of benzoguanamine and formaldehyde is preferable. Of the benzoguanamine resins, lower alkyl etherified benzoguanamine resins obtained by etherifying some or all of the methylol groups of the methylolated benzoguanamine resin with a lower alcohol are particularly preferable.

Specific examples of the benzoguanamine resin include Cymel 1123 (mixed etherified benzoguanamine resin of methyl ether and ethyl ether), Cymel 1123-10 (mixed etherified benzoguanamine resin of methyl ether and butyl ether) manufactured by Nippon Cytec Industries, Inc. Cymel 1128 (Butyl etherified benzoguanamine resin), Mycoat 102 (Methyletherified benzoguanamine resin), Mycoat 132 (Methyl and butyl mixed etherified benzoguanamine / melamine co-condensation resin), Mycoat 136 (Methyl) manufactured by Nihon Cytec Industries, Ltd. A mixed etherified benzoguanamine resin of ether and butyl ether) and the like can be preferably mentioned.

The epoxy resin is preferably a liquid or solid epoxy resin having an epoxy equivalent of about 100 to 4000 and a molecular weight of about 300 to 10,000. For example, bisphenol A type or bisphenol F type epoxy resin (manufactured by Japan Epoxy Resin Co., Ltd .: Epicoat 806, Epicoat 825, Epicoat 828, Epicoat 1001, Epicoat 1002, Epicoat 1003, Epicoat 1004, Epicoat 1055AF, Epicoat 1004AF, Epicoat 1007, Epicoat 1009, Epicoat 1010, etc.) Trifunctional or higher epoxy resin (Japan Epoxy Resin: Epicoat 152, Epicoat 154, Epicoat 180 series, Epicoat 157 series, Epicoat 1032 series, Sumitomo Chemical Co., Ltd .: Sumiepoxy ELM100, Daicel Chemical Kogyo Co., Ltd .: EHPE3150, Ciba Geigy: MT0163, etc.), terminal epoxidized oligomer (Ube) Hiker ETBN 1300 × 40 manufactured by Sansei Co., Ltd., Denarex R-45EPT manufactured by Nagase ChemteX Corporation), epoxidized polybutadiene (manufactured by Nippon Petrochemical Co., Ltd .: E-1000-8, E-1800-6.5, Daicel) Chemical Industry Co., Ltd .: Epolide PB3600, etc.), and alicyclic epoxy resins (Daicel Chemical Co., Ltd .: Celoxide 2021P, Celoxide 2080, Epolide GT400, EHPE) and the like can be mentioned. Of these, use of epoxidized polybutadiene or alicyclic epoxy resin is preferable because low warpage is easily obtained.

In the modified polyimide resin composition of the present invention, 1 to 50 parts by mass, preferably 2 to 40 parts by mass, more preferably 5 to 30 parts by mass of two or more phenolic hydroxyl groups with respect to 100 parts by mass of the modified polyimide resin. It can contain the compound which has. Examples of the compound having two or more phenolic hydroxyl groups include hydroquinone, 4,4'-dihydroxybiphenyl, and phenol resins such as phenol novolac and cresol novolac. As phenol resins, Meiwa Kasei Co., Ltd. phenol novolacs H-1, H-2, H-3, H-4, H-5, orthocresol novolac MER-130, triphenolmethane type MEH-7500, tetrakisphenol type MEH-7600, naphthol type MEH-7700, phenol aralkyl type MEH-7800, MEH-7785, triphenol type R-3, bisphenol novolac type MEP-6309, MEP-6309E, liquid phenol novolak MEH-8000H, MEH-8005, MEH-8010, MEH-8015, MEH-8205 and the like can be mentioned.

The modified polyimide resin composition usually contains a solvent. As the solvent, the organic solvent used in the synthesis of the modified polyimide resin can be used as it is, but preferably a nitrogen-containing solvent such as N, N-dimethylacetamide, N, N-diethylacetamide, N , N-dimethylformamide, N, N-diethylformamide, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N-methylcaprolactam, etc., sulfur-containing atomic solvents such as dimethyl sulfoxide, diethyl sulfoxide , Dimethylsulfone, diethylsulfone, hexamethylsulfuramide, and other oxygen-containing solvents such as phenolic solvents cresol, phenol, xylenol, diglyme-based solvents diethylene glycol dimethyl ether (diglyme), triethylene glycol dimethyl ether ( (Liglyme), tetraglyme, etc., ketone solvents such as acetone, acetophenone, propiophenone, cyclohexanone, isophorone, ether solvents such as ethylene glycol, dioxane, tetrahydrofuran, etc., and lactone solvents such as γ-butyrolactone. . In particular, N-methyl-2-pyrrolidone, N, N-dimethylsulfoxide, N, N-dimethylformamide, N, N-diethylformamide, N, N-dimethylacetamide, N, N-diethylacetamide, γ-butyrolactone, tri Ethylene glycol dimethyl ether or the like can be preferably used.

The thermosetting modified polyimide resin composition of the present invention preferably contains a curing catalyst such as a curing accelerating catalyst for accelerating the crosslinking reaction by heat treatment. Furthermore, the modified polyimide resin composition may contain fine fillers, pigments such as organic color pigments and inorganic color pigments, antifoaming agents, leveling agents and the like. As the fine filler, for example, conventionally known fine inorganic fillers such as silica, alumina, potassium carbonate, talc, barium sulfate, or fine organic fillers such as acrylic resin beads and urethane resin beads can be preferably cited. it can.

The above-mentioned acrylic resin beads and urethane resin beads are preferably spherical particles that can be easily obtained by suspension polymerization of methyl methacrylate or the like. The acrylic resin beads and urethane resin beads used in the present invention are preferably contained as fillers in the solution composition, and are preferably spherical crosslinked acrylic resin beads or crosslinked urethane resin beads.

The average particle size of the fine inorganic or organic filler is not particularly limited, but 0.001 to 20 μm, preferably 0.01 to 10 μm, more preferably 0.01 to 5 μm is suitable.

The modified polyimide resin composition of the present invention is not particularly limited, but the solution viscosity at room temperature (25 ° C.) is 5 to 1000 Pa · s, particularly 10 to 100 Pa · s, more preferably 10 to 60 Pa · s. However, it is preferable because workability such as screen printing, solution physical properties, and properties of the obtained cured insulating film are good.

The modified polyimide resin composition of the present invention can be suitably used for forming an insulating film (protective film) for electrical and electronic parts on which chip parts such as IC chips are mounted. For example, after printing and applying to the pattern surface of an insulating film having a wiring pattern formed of a conductive metal foil by screen printing or the like so that the thickness of the dry film is about 3 to 60 μm, 50 to 100 ° C. The solvent is removed by heat treatment at a temperature of about 5 to 60 minutes, and then cured by heat treatment at about 100 to 210 ° C., preferably at 110 to 200 ° C. for 5 to 120 minutes, preferably about 10 to 60 minutes. Preferably, a cured insulating film having an elastic modulus of 10 to 500 MPa is preferably formed.

The modified polyimide resin composition of the present invention has improved surface hardness and tackiness, is easy to suppress warpage, and not only provides strong adhesion to a sealing material or anisotropic conductive material. High flexibility, excellent electrical properties, good adhesion to conductive metals and substrates, heat resistance, solder heat resistance, solvent resistance (for example, acetone, isopropanol, methyl ethyl ketone, N-methyl-2) A cured insulating film having excellent solvent resistance to pyrrolidone), chemical resistance, flex resistance, and the like can be formed.

The composition for a modified polyimide resin insulating film of the present invention forms an insulating film having good performance as described above by heat treatment at a relatively low temperature of about 120 to 160 ° C., particularly about 120 ° C. (130 ° C. or less). It is possible. Therefore, it can also be suitably used as an interlayer adhesive for a multilayer wiring board.

Next, the second aspect of the present invention will be described. In the following description, when “same as the first mode” or “as described in the first mode” is described, it means that the preferable mode is also the mode described in the first mode. .

The modified polyimide resin of the present invention is a modified polyimide resin in which a soft segment composed of a polybutadiene segment or a polycarbonate segment is introduced into a hard segment having an imide structure, as described in the first embodiment.

A feature of the present invention is that a modified polyimide resin composition comprising a modified polyimide resin into which a soft segment composed of a polybutadiene segment or a polycarbonate segment prepared as described above is introduced, wherein acrylic resin beads are used as a filler. By adding, the surface hardness and fold resistance of the cured film obtained by heat treatment are improved at the same time.

As the modified polyimide resin, those described in the first embodiment can be used.

The modified polyimide resin composition of the present invention preferably comprises (A) 100 parts by mass of a modified polyimide resin into which a soft segment composed of a polybutadiene segment or a polycarbonate segment is introduced, (B) an epoxy compound, a polyvalent isocyanate compound, and an amino resin. At least one curable compound selected from the group consisting of 1 to 100 parts by weight, preferably 2 to 80 parts by weight, particularly 10 to 60 parts by weight, (C) 1 to 80 parts by weight of acrylic resin beads, and (D) an organic solvent. Consists of including.

The curable compound (B) can be used alone or in combination of two or more, but a combination of an epoxy compound and a polyvalent isocyanate compound or a combination of an epoxy compound and an amino resin is particularly preferable. If the amount used is more than the above range, the electrical insulation properties of the insulating film after curing will be reduced or tackiness will appear, and if it is too small, the heat resistance and chemical resistance of the insulating film after curing will deteriorate. Said range is preferred.

In order to obtain the effect of the first aspect, a guanamine resin which is a kind of amino resin is selected as the curable compound (B), and an epoxy resin is preferably used in combination.

The epoxy compound described in the first aspect can be used.

The isocyanate compound may be any compound as long as it has two or more isocyanate groups in one molecule. Examples of such isocyanate compounds include aliphatic, alicyclic or aromatic diisocyanates such as 1,4-tetramethylene diisocyanate, 1,5-pentamethylene diisocyanate, 1,6-hexamethylene diisocyanate. 2,2,4-trimethyl-1,6-hexamethylene diisocyanate, lysine diisocyanate, 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate), 1,3-bis (isocyanate methyl)- Cyclohexane, 4,4'-dicyclohexylmethane diisocyanate, tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, tolidine diisocyanate, xylylene diisocyanate Aneto, etc. can be mentioned.

Further, the isocyanate compound may be derived from an aliphatic, alicyclic or aromatic polyisocyanate, such as isocyanurate-modified polyisocyanate, burette-modified polyisocyanate, urethane-modified polyisocyanate, etc. .

Further, as the isocyanate compound, a blocked polyvalent isocyanate in which an isocyanate group of the polyvalent isocyanate is blocked with a blocking agent is preferably used.

As the block polyvalent isocyanate, in particular, Bernock D-500 (tolylene diisocyanate blocked), D-550 (1,6-hexamethylene diisocyanate blocked) manufactured by Dainippon Ink and Chemicals, Ltd., Takeda Mitsui Takenate Takenate B-830 (tolylene diisocyanate blocked), B-815N (4,4'-methylenebis (cyclohexyl isocyanate) blocked), B-842N (1,3-bis ( Isocyanatomethyl) cyclohexane blocked), B-846N (1,3-bis (isocyanatemethyl) cyclohexane blocked), B-874N (isophorone diisocyanate blocked), B-882N (1,6-hexamethylene) Diisocyanate broth ), Duranate MF-B60X (1,6-hexamethylene diisocyanate blocked), Asura Kasei Co., Ltd., Duranate MF-K60X (1,6-hexamethylene diisocyanate blocked), Duranate ME20-B80 (1) , 6-hexamethylene diisocyanate blocked), Elastolon BN-P17 (4,4′-diphenylmethane diisocyanate block) produced by Daiichi Kogyo Seiyaku Co., Ltd., Elastolon BN-04, Elastolon BN-08, Elastolon BN-44, Elastrone BN-45 (above, 3 to 5 functional groups per molecule of urethane-modified polyisocyanate block, all can be used after being dried and isolated in a water emulsion product) can be preferably used.

Examples of the amino resin include, but are not limited to, a lower alkyl etherified melamine resin or a lower alkyl etherified benzoguanamine resin obtained by etherifying a part or all of the methylol groups of a methylolated melamine resin or a methylolated benzoguanamine resin with a lower alcohol. Is preferred.

Specific examples of the melamine resin include, for example, Uban 20SE, 225 (all manufactured by Mitsui Toatsu), Super Becamine J820-60, L-117-60, L-109-65, 437-508- Butyl etherified melamine resins such as 60, L-118-60, G821-60 (all manufactured by Dainippon Ink and Chemicals); Cymel 300, 303, 325, 327, 350, 730, 736, 738 (all manufactured by Nihon Cytec Industries, Inc.), Melan 522, 523 (all manufactured by Hitachi Chemical Co., Ltd.), Nicarak MS001, MX 430, MX 650 (all manufactured by Sanwa Chemical Co., Ltd.), Sumimar M-55 M-100, M-40S (both manufactured by Sumitomo Chemical Co., Ltd.), Resimin 740, 747 (both Monsan Methyl etherified melamine resins such as Cymel 232, 266, XV-514, 1130 (all manufactured by Nihon Cytec Industries), Nicalak MX500, MX600, MS95 (all manufactured by Sanwa Chemical Co., Ltd.) ), Resimin 753, 755 (both manufactured by Monsanto Co., Ltd.), Summar M-66B (manufactured by Sumitomo Chemical Co., Ltd.), and the like.

As a specific example of the benzoguanamine resin, those described in the first aspect can be used. When such a benzoguanamine resin is contained, it is the invention of the first aspect at the same time.

As the acrylic resin beads (acrylic resin fine powder) used in the present invention, spherical particles that are easily obtained by suspension polymerization of methyl methacrylate or the like are suitable. The acrylic resin beads used in the present invention are preferably contained as a filler in the solution composition, and are preferably spherical crosslinked acrylic resin beads.

The average particle diameter of the acrylic resin beads is not particularly limited, but is 1 to 20 μm, preferably 1 to 10 μm, more preferably 1 to 5 μm. Those having an average particle size of 1 μm or less are difficult to obtain, and when the average particle size is increased, the effect of improving the folding resistance is reduced or the insulating film for a flexible wiring board made of fine wiring is used. Since it cannot be performed, it is not suitable.

Specific examples of acrylic resin beads include Art Pearl G-400, G-800, GR-400, GR-800, J-4PY, J-4P, J-4PY, J-5P, J-, manufactured by Negami Kogyo Co., Ltd. Preferred examples include 7P, J7PY, S-5P, and the like.

The modified polyimide resin composition of the present invention has 2 or more phenolic hydroxyl groups of 1 to 50 parts by mass, preferably 2 to 40 parts by mass, more preferably 5 to 30 parts by mass with respect to 100 parts by mass of the modified polyimide resin. Compounds can be included. The compound having two or more phenolic hydroxyl groups has been described in the first embodiment.

As the solvent of the modified polyimide resin composition, those described in the first embodiment can be used.

The modified polyimide resin composition of the present invention may contain a curing catalyst such as a curing accelerating catalyst for accelerating the crosslinking reaction by heat treatment. Furthermore, the modified polyimide resin composition may contain fine fillers other than acrylic resin beads, pigments such as organic color pigments and inorganic color pigments, antifoaming agents and leveling agents. As fine fillers other than acrylic resin beads, conventionally known fine inorganic fillers such as silica, alumina, potassium carbonate, talc and barium sulfate can be preferably exemplified.

The modified polyimide resin composition of the present invention is not particularly limited, but the solution viscosity at room temperature (25 ° C.) is 5 to 1000 Pa · s, particularly 10 to 100 Pa · s, more preferably 10 to 60 Pa · s. It is suitable in view of workability such as printing, solution properties, and characteristics of the obtained cured insulating film.

The modified polyimide resin composition of the present invention provides strong adhesion to a sealing material or anisotropic conductive material in addition to improved surface hardness and fold resistance, and is less likely to warp and has flexibility. High, excellent electrical properties, good adhesion to conductive metals and substrates, heat resistance, solder heat resistance, solvent resistance (for example, resistance to acetone, isopropanol, methyl ethyl ketone, N-methyl-2-pyrrolidone) A cured insulating film excellent in solvent resistance, chemical resistance, flex resistance and the like can be formed.

The composition for a modified polyimide resin insulating film of the present invention can form an insulating film having good performance as described above, particularly by heat treatment at a relatively low temperature of about 160 ° C. Therefore, it can also be suitably used as an interlayer adhesive for a multilayer wiring board.

Hereinafter, the present invention will be further described with reference to examples and comparative examples. The present invention is not limited to the following examples.

In the following examples, measurement and evaluation were performed by the following methods.
[Tackiness test]
A coating film of a modified polyimide resin composition of a sample is formed on a polyimide film having a thickness of 35 μm by using an applicator, and this is cured by heating at 80 ° C. for 30 minutes and then at 120 ° C. for 90 minutes to cure the cured film having a thickness of 10 μm. After forming this, the laminate of this polyimide film and cured film was cut into a size of 2.5 cm × 10 cm as a test piece.

The test method is as follows: a test piece is placed on a hot plate heated to each set temperature (here, 110 ° C., 120 ° C., 130 ° C., and 140 ° C.) and heated to the same temperature as the hot plate. The weight (300 g in weight) was placed on the test piece for 30 seconds and the weight was lifted. When the weight was pulled up, the state where the test piece was caught on the weight was regarded as unacceptable (x), and the state where it was allowed to stand on the hot plate was regarded as acceptable (◯). The test was performed three times at each set temperature.

[MIT folding test]
After forming a circuit having a wiring width of 15 μm, an inter-wiring distance of 15 μm, and a circuit length of 20 cm on the surface of the base material using a two-layer CCL in which a 7 μm-thick copper layer is laminated on a 35 μm-thick polyimide layer, A flexible substrate having a surface plated with 3 μm thick Sn was prepared. A coating film of the modified polyimide resin composition of the sample is formed on the circuit area of the flexible substrate using a screen printing machine (manufactured by Neo Techno Japan, semi-automatic screen printing machine NT-15SS-U). Then, a test piece was prepared by heating and curing at 120 ° C. for 90 minutes to form a cured film having a thickness of 10 μm.

The fold resistance of this test piece was measured according to JIS P 8115 with an MIT type soft fatigue tester DA type (manufactured by Toyo Seiki Seisakusho). The measurement was performed under the conditions of 90 ° bending (R = 0.5) and a bending speed of 90 times / minute.

[Pencil hardness test]
A coating film of a modified polyimide resin composition as a sample is formed on the surface of a 50 μm thick copper foil using an applicator and cured by heating at 80 ° C. for 30 minutes and then at 120 ° C. for 90 minutes to obtain a cured film having a thickness of 20 μm. A specimen was formed as a test piece. The cured film of the obtained test piece was subjected to the procedure of JIS-K5600-5-4 using a pencil scratch coating film hardness tester (manufactured by Toyo Seiki Seisakusho) as an apparatus and 4B-2H (Mitsubishi UNI) as a pencil. Pencil hardness was measured.

[Measurement of gel fraction]
A film of the modified polyimide resin composition of the sample is formed on the glass coated with a release agent, and this is cured by heating at 80 ° C. for 30 minutes and then at 120 ° C. for 90 minutes to form a cured film having a thickness of 60 μm. After that, the cured film was peeled off from the glass and cut into a size of 5 cm × 10 cm was used as a test piece.

The test piece was immersed in acetone for 30 minutes, the mass of the test piece before and after immersion was measured, and the residual ratio of the mass was defined as the gel fraction.

Gel fraction (mass%) = [(mass after acetone immersion) / (mass before acetone immersion)] × 100

[Tensile modulus, elongation]
A heat treatment was performed at 80 ° C. for 30 minutes and then at 120 ° C. for 90 minutes to prepare a 70 μm thick sheet-like cured film. Tensile modulus and elongation were measured at a crosshead speed of 50 mm / min and a distance between chucks of 5 cm in an atmosphere of a temperature of 25 ° C. and a humidity of 50% RH.

〔warp〕
A coating film of the modified polyimide resin composition of the sample was formed on the surface of the polyimide film having a thickness of 25 μm by using an applicator, and this was cured by heat treatment at 80 ° C. for 30 minutes and then at 120 ° C. for 90 minutes to form a 10 μm thick film. A cured film was formed. A laminate of the polyimide film and the cured film was cut into a 5 cm square to obtain a test piece. The test piece was placed on a horizontal base with the cured film facing upward, and the gap between the four corners of the test piece and the horizontal base was measured with a caliper, and the average value of each gap was defined as the “warp” amount.

The compounds, curing agents, curing catalysts and fillers used in the following examples will be described.
[Tetracarboxylic acid component]
2,3,3 ′, 4′-biphenyltetracarboxylic dianhydride (manufactured by Ube Industries, Ltd.)
[Diamine compound]
Isophoronediamine (manufactured by Wako Pure Chemical Industries, Ltd.)
[Monoamine compound having one alcoholic hydroxyl group]
3-Aminopropanol (Wako Pure Chemical Industries, Ltd.)
〔solvent〕
γ-Butyrolactone (Mitsubishi Chemical Corporation)
[Polycarbonate diol]
ETERNACOLL UH-200 (Ube Industries, Ltd., average molecular weight 1997)
(Reactive polar group-containing diol)
2,2-bis (hydroxymethyl) propionic acid (manufactured by Tokyo Chemical Industry Co., Ltd.)
[Diisocyanate compound]
4,4'-Diphenylmethane diisocyanate (Nippon Polyurethane Industry Co., Ltd.)
[Guanamine resin]
Mycoat 136 (Nippon Cytec Industries, Ltd., mixed etherified benzoguanamine resin of methyl ether and butyl ether, imino group type)
[Melamine resin]
Cymel 211 (Nippon Cytec Industries, Ltd., mixed etherified melamine resin of methyl ether and butyl ether, imino group type)
Cymel 236 (manufactured by Nippon Cytec Industries, Ltd., mixed etherified melamine resin of methyl ether and butyl ether, fully alkylated type)
[Epoxy compound]
Celoxite 2021P (manufactured by Daicel Chemical Industries, Ltd.)
[Diisocyanate compound]
Takenate B-830 (Mitsui Chemicals Polyurethanes, Tolylene Diisocyanate blocked)
[Compounds having two or more phenolic hydroxyl groups (phenolic resin)]
H-1 (Maywa Kasei Co., Ltd., phenol novolak)
[Fine powder silica]
Aerosil R972 (Nippon Aerosil Co., Ltd., specific surface area (BET method): 110 m ² / g)
Aerosil # 50 (Nippon Aerosil Co., Ltd. average particle size 30 nm)
Silo Hovic 100 (Fuji Silysia Chemical Hydrophobic Silica Gel)
[Barium sulfate]
BARIFINE B-30: (manufactured by Sakai Chemical Industry Co., Ltd., average particle size: 0.3 μm)
[Curing catalyst]
Curesol 2E4MZ (manufactured by Shikoku Chemicals Co., Ltd., 2-ethyl-4-methylimidazole)
Diazabicycloundecene (DBU: Aldrich)
[Defoamer]
Disparon OX-881 (manufactured by Enomoto Kasei)
[Acrylic resin beads]
Art Pearl J4PY (Negami Kogyo Co., Ltd., average particle size 2.2μm)
Art Pearl J7PY (Negami Kogyo Co., Ltd., average particle size 6.6μm)
[Urethane resin beads]
Art Pearl C-800 (Negami Kogyo Co., Ltd., average particle size 6.6μm)
Art Pearl JB-1000T (Negami Kogyo Co., Ltd., average particle size 3.5μm)
[Amino resin beads]
D poster M05 (Nippon Shokubai Co., Ltd., 4-6μm)
[Surfactant]
LF-1983 (Made by Enomoto Kasei Co., Ltd.)

[Reference Example 1]
Method for producing alcoholic hydroxyl-terminated imide oligomer solution 2,5,3 ', 4'-biphenyltetracarboxylic dianhydride was added to a 5 liter glass separable flask equipped with a stirrer, a nitrogen inlet tube, and a Dean-Star cleaver. 1471 g (5 mol), ethanol 507 g (11 mol) and γ-butyrolactone 2092 g were charged and stirred at 90 ° C. for 1 hour in a nitrogen atmosphere. Next, 376 g (5 mol) of 3-aminopropanol and 426 g (2.5 mol) of isophoronediamine were charged and heated in a nitrogen atmosphere at 120 ° C. for 2 hours and 180 ° C. for 2 hours to react with water generated by the imidization reaction. It was removed by blowing nitrogen into the liquid. This alcoholic hydroxyl group-terminated imide oligomer solution had a solid content of 51.6%.

[Reference Example 2]
Method for Producing Modified Polyimide Resin Solution In a 5 liter glass separable flask equipped with a stirrer and a nitrogen inlet tube, ETERNACOLL UH-200 1198.20 g (0.60 mol), the alcoholic hydroxyl group terminal synthesized in Reference Example 1 974.13 g of an imide oligomer solution, 80.48 g (0.60 mol) of 2,2-bis (4-hydroxymethyl) propionic acid and 2228.90 g of γ-butyrolactone were charged and stirred at 50 ° C. for 1 hour in a nitrogen atmosphere. . Subsequently, 429.00 g (1.71 mol) of 4,4′-diphenylmethane diisocyanate was added, and the mixture was stirred at 60 ° C. for 3 hours and at 80 ° C. for 10 hours. The resulting modified polyimide resin solution was a solution having a polymer solid content concentration of 45.7% by weight and a viscosity of 389 Pa · s.

[Example A-1]
In the modified polyimide resin solution obtained in Reference Example 2, in a glass container, 20 parts by mass of guanamine resin Mycoat 136 (M136) and 4.1 parts of epoxy resin ceroxide 2021P with respect to 100 parts by mass of the modified polyimide resin. Parts by weight, 2.5 parts by weight of phenolic resin H-1 and 0.5 parts by weight of amine-based curing catalyst 2E4MZ, 0.5 parts by weight of diazabicycloundecene, and further 7 parts by weight of Aerosil R972, 5 parts by mass of Silo Hovic 100 and 7.5 parts by mass of OX881 as an antifoaming agent were added, and the mixture was stirred and kneaded to obtain a uniformly mixed modified polyimide resin composition. Moreover, about the cured film of this modified polyimide resin composition, tack property, pencil hardness, gel fraction, and curvature were evaluated. The results are shown in Table 1.

Example A-2
The same procedure as in Example A-1 except that Mycoat 136 (M136) of guanamine resin was changed to 5 parts by weight, and 25 parts by weight of Aerosil # 50 and 30 parts by weight of barium sulfate B54 were used as the filler. A modified polyimide resin composition was obtained. This modified polyimide resin composition was evaluated in the same manner as in Example A-1. The results are shown in Table 1.

[Comparative Example A-1]
A modified polyimide resin composition was obtained in the same manner as in Example A-1, except that 4.5 parts by mass of B830, which is a diisocyanate compound, was used instead of the guanamine resin as a curing component. This modified polyimide resin composition was evaluated in the same manner as in Example A-1. The results are shown in Table 1.

[Comparative Example A-2]
A modified polyimide resin composition was obtained in the same manner as in Example A-1, except that 20 parts by mass of melamine resin Cymel 211 (C211) was used instead of the curable guanamine resin. This modified polyimide resin composition was evaluated in the same manner as in Example A-1. The results are shown in Table 1.

[Comparative Example A-3]
A modified polyimide resin composition was obtained in the same manner as in Example A-1, except that 20 parts by mass of melamine resin Cymel 236 (C236) was used instead of the curable guanamine resin. This modified polyimide resin composition was evaluated in the same manner as in Example A-1. The results are shown in Table 1.

[Example B-1]
In a glass container, in the modified polyimide resin solution obtained in Reference Example 2, 3.5 parts by mass of epoxy resin ceroxide 2021P with respect to 100 parts by mass of modified polyimide resin, 10 parts by mass of amino resin (guanamine resin) M136, 2.5 parts by mass of phenol resin H-1 and 0.5 parts by mass of amine-based curing catalyst 2E4MZ, 0.5 parts by mass of diazabicycloundecene, 7 parts by mass of Aerosil R972, acrylic resin beads (Art 15 parts by mass of Pearl J4PY) and 7.5 parts by mass of LF-1983 as a surfactant were added, and the mixture was stirred and kneaded to obtain a uniformly mixed modified polyimide resin composition. Moreover, about the cured film of this modified polyimide resin composition, tensile elasticity modulus, bendability, board | substrate curvature amount, and pencil hardness were evaluated. The results are shown in Table 2.

[Example B-2]
A modified polyimide resin composition was obtained in the same manner as in Example B-1, except that the acrylic resin beads (Art Pearl J4PY) were changed from 15 parts by mass to 20 parts by mass. This modified polyimide resin composition was evaluated in the same manner as in Example B-1. The results are shown in Table 2.

Example B-3
A modified polyimide resin composition was obtained in the same manner as in Example B-1, except that the acrylic resin beads (Art Pearl J4PY) were changed from 15 parts by mass to 30 parts by mass. This modified polyimide resin composition was evaluated in the same manner as in Example B-1. The results are shown in Table 2.

[Example B-4]
A modified polyimide resin composition was obtained in the same manner as in Example B-1, except that the acrylic resin beads (Art Pearl J4PY) were changed from 15 parts by mass to 50 parts by mass. This modified polyimide resin composition was evaluated in the same manner as in Example B-1. The results are shown in Table 2.

[Example B-5]
A modified polyimide resin composition was obtained in the same manner as in Example B-2 except that the acrylic resin beads (Art Pearl J4PY) were changed to acrylic resin beads (Art Pearl J7PY). This modified polyimide resin composition was evaluated in the same manner as in Example B-1. The results are shown in Table 2.

[Comparative Example B-1]
A modified polyimide resin composition was obtained in the same manner as in Example B-2 except that the acrylic resin beads (Art Pearl J4PY) were changed to amino resin beads (Eposter M05). This modified polyimide resin composition was evaluated in the same manner as in Example B-1. The results are shown in Table 2.

[Comparative Example B-2]
A modified polyimide resin composition was obtained in the same manner as in Example B-2 except that the acrylic resin beads (Art Pearl J4PY) were changed to urethane resin beads (Art Pearl JB-1000T). This modified polyimide resin composition was evaluated in the same manner as in Example B-1. The results are shown in Table 2.

[Comparative Example B-3]
A modified polyimide resin composition was obtained in the same manner as in Example B-2 except that the acrylic resin beads (Art Pearl J4PY) were changed to urethane resin beads (Art Pearl C-800). This modified polyimide resin composition was evaluated in the same manner as in Example B-1. The results are shown in Table 2.

According to the present invention, in a modified polyimide resin composition comprising a modified polyimide resin introduced with a soft segment comprising a polybutadiene segment or a polycarbonate segment, the surface hardness, tackiness, and warpage of the cured film obtained by heat treatment are reduced. An improved modified polyimide resin composition can be provided. The cured film obtained by heat-treating this modified polyimide resin composition is excellent in electrical insulation, heat resistance, flexibility and the like, and particularly has improved surface hardness, tackiness and warpage. It can be suitably used as an insulating film for a wiring board.

According to one embodiment of the present invention, in a modified polyimide resin solution composition comprising a modified polyimide resin into which a soft segment comprising a polybutadiene segment or a polycarbonate segment is introduced, the surface hardness and resistance of a cured film obtained by heat treatment are obtained. A modified polyimide resin solution composition capable of improving the foldability can be provided. The cured film obtained by heat-treating this modified polyimide resin solution composition is excellent in electrical insulation, heat resistance, flexibility and the like, and in particular, has improved surface hardness and fold resistance. It can be suitably used as an insulating film for a plate.

Claims

A modified polyimide resin composition comprising a modified polyimide resin into which a soft segment composed of a polybutadiene segment or a polycarbonate segment is introduced, and a guanamine resin.
The modified polyimide resin composition according to claim 1, further comprising an epoxy resin.
The modified polyimide resin composition according to claim 1 or 2, wherein the modified polyimide resin composition contains 1 to 60 parts by mass of a guanamine resin with respect to 100 parts by mass of the modified polyimide resin.
The modified polyimide resin composition according to any one of claims 1 to 3, wherein the guanamine resin is a condensate of benzoguanamine and formaldehyde.
The modified polyimide resin composition according to any one of claims 1 to 4, further comprising acrylic resin beads.
6. The modified polyimide resin composition according to claim 5, wherein acrylic resin beads are contained at a ratio of 10 to 80 parts by mass with respect to 100 parts by mass of the modified polyimide resin.
The modified polyimide resin composition according to claim 5 or 6, wherein the acrylic resin beads have an average particle size of 10 µm or less.
The modified polyimide resin composition according to any one of claims 1 to 7, further comprising an organic solvent.
A cured film obtained by heat-treating the modified polyimide resin composition according to any one of claims 1 to 8.
10. The cured film according to claim 9, which is an insulating film of a flexible wiring board.