JPWO2011004756A1 - Thermosetting composition for protective film of wiring board - Google Patents

Abstract

Provided is a thermosetting composition for a protective film of a wiring board excellent in low warpage, flexibility and long-term electrical insulation reliability. The thermosetting composition for a protective film of a wiring board of the present invention has an epoxy group-containing compound having a tricyclodecane structure, a functional group capable of reacting with an epoxy group, and a structural unit represented by the formula (1) A polyurethane and a solvent are essential components. (In the formula, R1 represents an alkylene group having 3 to 18 carbon atoms, and n represents an integer of 1 or more.) As an epoxy group-containing compound having a tricyclodecane structure, a compound of formula (2) is preferably used. It is done.

Description

  The present invention relates to a novel thermosetting composition for a protective film of a wiring board, a protective film for a wiring board obtained by curing the thermosetting composition for the protective film, a flexible wiring board covered with the protective film, and The present invention relates to a method for manufacturing a flexible wiring board covered with the protective film. More specifically, a thermosetting composition for a protective film of a wiring board excellent in low warpage, flexibility, and long-term electrical insulation reliability, and a wiring board obtained by curing the thermosetting composition for a protective film. The present invention relates to a protective film, a flexible wiring board partially or entirely covered with the protective film, and a method for manufacturing a flexible wiring board covered with the protective film.

Conventionally, surface protection films for flexible wiring circuits are made by punching a die that matches the pattern of a polyimide film called a coverlay film, and then pasting it with an adhesive, or UV curing with flexibility. A type or a thermosetting type overcoat agent is applied by a screen printing method, and the latter is particularly useful in terms of workability. As these curing type overcoat agents, resin compositions mainly composed of epoxy resin, acrylic resin, or composites thereof are known. These are often mainly composed of resins that have been modified, such as the introduction of a butadiene skeleton, a siloxane skeleton, a polycarbonate diol skeleton, a long-chain aliphatic skeleton, and the like. In addition, while suppressing the deterioration of chemical resistance and electrical insulation as much as possible, the improvement of flexibility and the occurrence of warpage due to curing shrinkage have been suppressed.
However, in recent years, flexible substrates have become lighter and thinner as electronic devices become lighter and smaller, and accordingly, the effects of flexibility and curing shrinkage of the resin composition to be overcoated are becoming more prominent. . For this reason, in the present situation, the curing type overcoat agent cannot satisfy the required performance in terms of warpage due to flexibility and curing shrinkage.

  For example, JP-A-11-61038 (Patent Document 1) discloses a resin composition using a polybutadiene blocked isocyanate and a polyol, but the cured product is excellent in terms of flexibility and shrinkage. However, heat resistance is not enough.

  Japanese Patent Application Laid-Open No. 2004-137370 (Patent Document 2) includes a polyamide-imide resin obtained by reacting a polycarbonate diol and a diisocyanate compound and a terminal diisocyanate polyurethane and trimellitic acid, and an amine-type epoxy resin. Although the composition containing this was disclosed, there existed a fault that the long-term reliability of the electrical property of the hardened | cured material obtained from a polyamideimide resin and an amine type epoxy resin was not enough.

  JP-A 2006-307183 (Patent Document 3) discloses a composition containing a carboxyl group-containing polyurethane polyimide and an epoxidized polybutadiene. This composition is dried to be a solvent. At the time of removal, the carboxyl group-containing polyurethane polyimide and the epoxidized polybutadiene are liable to cause a phase separation structure and have a disadvantage that a uniform film is hardly formed.

  Japanese Patent Application Laid-Open No. 2004-182792 (Patent Document 4) discloses a polyamideimide resin having an organosiloxane skeleton, but the adhesion between the cured product and the substrate is not good. It is necessary to use a special solvent such as methyl-2-pyrrolidone, which may cause a problem because the emulsion may be dissolved particularly during screen printing.

  JP-A 2006-348278 (Patent Document 5) discloses a carboxyl group-containing polyurethane and an epoxy compound having a polyol unit selected from the group consisting of polybutadiene polyol, polyisoprene polyol, hydrogenated polybutadiene polyol and hydrogenated polyisoprene polyol. A composition comprising is disclosed. For example, when focusing on the circuit pattern forming method used in the COF (Chip on Film) mounting method, the wiring that is currently widely used in the COF mounting method is produced by the subtractive method. . As an insulating film for wiring produced by these subtractive methods, a cured product obtained from the composition disclosed in Patent Document 5 exhibits sufficient insulating performance.

  Furthermore, Japanese Unexamined Patent Publication No. 2007-10037 (Patent Document 6) discloses a solder resist ink containing a carboxyl group-containing polyurethane having an organic residue derived from dimer diol and an epoxy compound. Regarding the cured product obtained from this composition, the solder resist ink disclosed in Patent Document 6 exhibits sufficient insulating performance as an insulating coating for wiring produced by the subtractive method.

JP-A-11-61038 JP 2004-137370 A JP 2006-307183 A JP 2004-182792 A JP 2006-348278 A JP 2007-100037 A

However, with the development of the semi-additive method, the distance between wirings of the flexible wiring board is expected to be further narrowed (for example, 20 μm pitch or less).
With this further narrowing of the pitch, the development of a resin with better electrical insulation performance is required.
An object of the present invention is to provide a thermosetting composition for a protective film of a wiring board that is flexible and can obtain a protective film having good electrical insulation characteristics even in a semi-additive method, and a wiring board obtained by curing the composition An object of the present invention is to provide a protective film, a flexible wiring board covered with the protective film, and a method of manufacturing the flexible wiring board.

  As a result of repeated studies to solve the above problems, the present inventors have used a curable composition containing a polyurethane having a specific structural unit, an epoxy group-containing compound having a specific structure, and a solvent. The present inventors have found that a cured product obtained by curing this curable composition is excellent in flexibility and electrical insulating properties, and the present invention has been completed.

（式中、Ｒ^１は、炭素数３〜１８のアルキレン基を表し、ｎは１以上の整数を表す。）That is, the present invention (I) comprises an epoxy group-containing compound having a tricyclodecane structure, a polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by formula (1), and a solvent as essential components. It is a thermosetting composition for protective film of a wiring board.

(In the formula, R ¹ represents an alkylene group having 3 to 18 carbon atoms, and n represents an integer of 1 or more.)

  This invention (II) is a protective film of a wiring board obtained by hardening | curing the thermosetting composition for protective films of the wiring board of this invention (I).

  In the present invention (III), part or all of the surface of the flexible wiring board in which the wiring is formed on the flexible substrate is covered with the protective film of the wiring board of the present invention (II). This is a flexible wiring board covered with a protective film.

  In the present invention (IV), a printed film is formed on the pattern by printing the thermosetting composition for the protective film of the wiring board of the present invention (I) on the wiring pattern portion subjected to tin plating of the flexible wiring board. Then, the printed film is heated and cured at 80 to 130 ° C. to form a protective film, which is a method for producing a flexible wiring board covered with a protective film.

  Further, the present invention relates to the following thermosetting composition for a protective film for a wiring board according to [1] to [12], a protective film for a wiring board according to [13], a flexible wiring board according to [14], and [15]. ] Is a method for manufacturing a flexible wiring board.

[1] An epoxy group-containing compound having a tricyclodecane structure, a polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1), and a protective film for a wiring board comprising a solvent as essential components Thermosetting composition.

[2] The epoxy group-containing compound having a tricyclodecane structure has a tricyclo [5.2.1.0 ^2,6 ] decane structure or a tricyclo [3.3.1.1 ^3,7 ] decane structure, The thermosetting composition for a protective film of a wiring board according to [1], which is an epoxy group-containing compound having an aromatic ring structure.

（式中、ｌは、０または１以上の整数を表す。）[3] The thermosetting composition for a protective film for a wiring board according to [2], wherein the epoxy group-containing compound having a tricyclodecane structure is a compound represented by the formula (2).

(In the formula, l represents 0 or an integer of 1 or more.)

[4] The polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) has a functional group capable of reacting with an epoxy group and represented by the formula (1) The thermosetting composition for a protective film of a wiring board according to any one of [1] to [3], which is a polyurethane polyimide having an imide bond.

[5] The thermosetting composition for a protective film of a wiring board according to any one of [1] to [4], wherein the functional group capable of reacting with an epoxy group is a carboxyl group.

[6] The thermosetting composition for a protective film of a wiring board according to any one of [1] to [4], wherein the functional group capable of reacting with an epoxy group is an acid anhydride group.

（式中、Ｒ^２、Ｒ^３は、それぞれ独立に、２価の脂肪族または芳香族炭化水素基を示し、Ｙ^１はテトラカルボン酸またはその酸無水物基から誘導される４価の有機基を示し、Ｘ^１はジアミン或いはジイソシアネートから誘導される２価の有機基を示し、ｍは、０〜２０の整数である。）[7] A polyurethane polyimide having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) and further having an imide bond reacts the following components (a) to (d): The thermosetting composition for a protective film for a wiring board according to [4] or [5], which is a polyurethane polyimide obtained by the above process.
Component (a) diisocyanate,
Component (b) (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms,
Component (c) Diol having a carboxyl group, and Component (d) A bifunctional hydroxyl-terminated imide represented by the formula (3).

Wherein R ² and R ³ each independently represents a divalent aliphatic or aromatic hydrocarbon group, and Y ¹ represents a tetravalent organic group derived from a tetracarboxylic acid or an acid anhydride group thereof. X ¹ represents a divalent organic group derived from diamine or diisocyanate, and m is an integer of 0 to 20.)

（式中、複数個のＲ^４は、それぞれ独立に炭素数３〜１８のアルキレン基であり、複数個のＲ^５は、それぞれ独立に炭素数３〜１８のアルキレン基であり、ａ及びｂは、それぞれ独立に１〜２０の整数であり、複数個のＸ^２は、それぞれ独立に２価の有機基である。）

（式中、複数個のＲ^６は、それぞれ独立に炭素数３〜１８のアルキレン基であり、複数個のＲ^７は、それぞれ独立に炭素数３〜１８のアルキレン基であり、ｃ及びｄは、それぞれ独立に１〜２０の整数であり、複数個のＸ^３は、それぞれ独立に２価の有機基であり、Ｙ^２は、ＣＨ_２、ＳＯ_２またはＯである。）

式中、複数個のＲ^８は、それぞれ独立に炭素数３〜１８のアルキレン基であり、複数個のＲ^９は、それぞれ独立に炭素数３〜１８のアルキレン基であり、ｅ及びｆは、それぞれ独立に１〜２０の整数であり、複数個のＸ^４は、それぞれ独立に２価の有機基であり、Ｙ^３は、式（７）〜式（３３）のいずれかの基である。

[8] A polyurethane polyimide having a functional group capable of reacting with an epoxy group, having a structural unit represented by the formula (1), and further having an imide bond is selected from the group consisting of formulas (4) to (6) The thermosetting composition for a protective film of a wiring board according to [4] or [6], which is a polyurethane polyimide having at least one selected structural unit.

(In the formula, a plurality of R ⁴ are each independently an alkylene group having 3 to 18 carbon atoms, a plurality of R ⁵ are each independently an alkylene group having 3 to 18 carbon atoms, and a and b are And each independently represents an integer of 1 to 20, and a plurality of X ² are each independently a divalent organic group.)

(Wherein a plurality of R ⁶ are each independently an alkylene group having 3 to 18 carbon atoms, a plurality of R ⁷ are each independently an alkylene group having 3 to 18 carbon atoms, and c and d are And each independently represents an integer of 1 to 20, a plurality of X ³ are each independently a divalent organic group, and Y ² is CH ₂ , SO ₂ or O.)

In the formula, a plurality of R ⁸ are each independently an alkylene group having 3 to 18 carbon atoms, a plurality of R ⁹ are each independently an alkylene group having 3 to 18 carbon atoms, and e and f are Each independently represents an integer of 1 to 20, a plurality of X ⁴ are each independently a divalent organic group, and Y ³ is any group of formulas (7) to (33).

[9] A polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) comprises the following component (a), component (b), component (c) and component (e): The thermosetting composition for a protective film for a wiring board according to any one of [1] to [3], which is a polyurethane obtained by a reaction.
Component (a) diisocyanate,
Component (b) (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms,
Component (c) a diol having a carboxyl group,
Component (e) A compound having 3 or more hydroxyl groups in one molecule.

[10] A polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) has a functional group capable of reacting with an epoxy group and represented by the formula (1) And [1] to [3], [5], [6] and [9], wherein the polyurethane further contains an organic residue derived from dimer diol. Thermosetting composition for protective film of wiring board.

[11] The solvent is a mixed solvent containing at least one solvent having a boiling point of 170 ° C. or more and less than 200 ° C. under atmospheric pressure and at least one solvent having a boiling point of 200 ° C. to 220 ° C. under atmospheric pressure. The thermosetting composition for a protective film for a wiring board according to any one of [1] to [10].
[12] The solvent is a mixed solvent containing at least one solvent selected from the following group A and at least one solvent selected from the following group B as essential components [1] -The thermosetting composition for protective films of the wiring board in any one of [11].
Group A: diethylene glycol dimethyl ether (boiling point 162 ° C.), diethylene glycol diethyl ether (boiling point 189 ° C.), diethylene glycol ethyl methyl ether (boiling point 176 ° C.), dipropylene glycol dimethyl ether (boiling point 171 ° C.), 3-methoxybutyl acetate (boiling point 171) ° C), ethylene glycol monobutyl ether acetate (boiling point 192 ° C)
Group B: Diethylene glycol butyl methyl ether (boiling point 212 ° C.), tripropylene glycol dimethyl ether (boiling point 215 ° C.), triethylene glycol dimethyl ether (boiling point 216 ° C.), ethylene glycol dibutyl ether (boiling point 203 ° C.), diethylene glycol monoethyl ether acetate (boiling point) 217 ° C.), γ-butyrolactone (boiling point 204 ° C.)

[13] A protective film for a wiring board obtained by curing the thermosetting composition for a protective film for a wiring board according to any one of [1] to [12].

[14] A part of or all of the surface of the flexible wiring board in which the wiring is formed on the flexible substrate is covered with the protective film of the wiring board according to [13]. A flexible wiring board covered with a protective film.

[15] Printing on the pattern by printing the thermosetting composition for a protective film of a wiring board according to any one of [1] to [12] on a tinned wiring pattern portion of a flexible wiring board A method for producing a flexible wiring board covered with a protective film, comprising forming a film and forming the protective film by heating and curing the printed film at 80 to 130 ° C.

The cured product of the present invention has no tack, good handling properties, good flexibility and moisture resistance, long-term electrical insulation reliability at a high level, and low warpage. In addition, the adhesiveness with the underfill material is good, and the solvent resistance is also good. For this reason, when applying the thermosetting composition of the present invention to a flexible substrate such as a flexible wiring board or a polyimide film, and then creating a cured product (protective film) by a curing reaction, the flexible wiring board with a protective film In addition, the warp of the flexible base material with a protective film is small, and the positioning of the IC chip mounting process is facilitated thereafter.
Moreover, since the cured product of the present invention has flexibility, it is possible to provide a flexible wiring board (for example, a flexible printed wiring board such as COF) with an electrically insulating protective film that is less susceptible to cracking.

（式中、Ｒ^１は、炭素数３〜１８のアルキレン基を表し、ｎは１以上の整数を表す。）Hereinafter, the present invention will be specifically described.
First, the present invention (I) will be described.
The present invention (I) includes an epoxy group-containing compound having a tricyclodecane structure, a polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1), and a wiring comprising a solvent as essential components It is a thermosetting composition for a protective film of a plate.

(In the formula, R ¹ represents an alkylene group having 3 to 18 carbon atoms, and n represents an integer of 1 or more.)

  The present invention (II) is a protective film for a wiring board obtained by curing the protective film thermosetting composition for the wiring board of the present invention (I).

  The epoxy group-containing compound having a tricyclodecane structure, which is one of the essential components of the composition of the present invention (I), is not particularly limited as long as it is a compound having a tricyclodecane structure and an epoxy group in the molecule.

Examples of the tricyclodecane structure include a tricyclo [5.2.1.0 ^2,6 ] decane structure or a tricyclo [3.3.1.1 ^3,7 ] decane structure.

（式中、ｌは、０または１以上の整数を表す。）

（式中、ｇは、０または１以上の整数を表す。）Examples of the epoxy group-containing compound having a tricyclo [5.2.1.0 ^2,6 ] decane structure include compounds represented by the following formula (2) and the following formula (34).

(In the formula, l represents 0 or an integer of 1 or more.)

(In the formula, g represents 0 or an integer of 1 or more.)

Examples of the epoxy group-containing compound having a tricyclo [3.3.1.1 ^3,7 ] decane structure include compounds represented by the following formula (35) to the following formula (38).

Among these compounds having a tricyclo [5.2.1.0 ^2,6 ] decane structure or a tricyclo [3.3.1.1 ^3,7 ] decane structure and an epoxy group, it is preferable to reduce the water absorption rate. Specifically, an epoxy group containing a tricyclo [5.2.1.0 ^2,6 ] decane structure or a tricyclo [3.3.1.1 ^3,7 ] decane structure and having an aromatic ring structure Compounds are preferred.
Among the formulas (2) and (34) to (38), the compounds represented by the formulas (2) and (35) to (38) are applicable.

Among epoxy group-containing compounds having a tricyclo [5.2.1.0 ^2,6 ] decane structure or a tricyclo [3.3.1.1 ^3,7 ] decane structure and having an aromatic ring structure In view of the ease, the compound represented by formula (2) is particularly preferred.
The compound represented by the formula (2) is commercially available from DIC Corporation (grade names: Epicron HP-7200L, Epicron HP-7200, Epicron HP-7200H, Epicron HP-7200HH), and also from Nippon Kayaku Co., Ltd. It is commercially available under the grade names XD-1000-2L and XD-1000 and is easily available.

The amount of the epoxy group-containing compound having a tricyclodecane structure, which is an essential component of the present invention (I), has a functional group capable of reacting with an epoxy group, which is an essential component of the present invention (I), which will be described later, and It can be shown by the ratio of the number of functional groups capable of reacting with epoxy groups contained in the polyurethane having the structural unit represented by formula (1) and the number of epoxy groups.
When the functional group capable of reacting with the epoxy group is a group that reacts 1: 1 with the epoxy group, the functional group capable of reacting with the epoxy group contained in the thermosetting composition of the present invention (I) The ratio of the number and the number of epoxy groups of the epoxy group-containing compound having a tricyclodecane structure is preferably in the range of 1/3 to 2/1, more preferably 1 / 2.5 to 1.5 /. 1 range. When this ratio is smaller than 1/3, there is a high possibility that many unreacted epoxy groups remain, which is not preferable. On the other hand, if this ratio is larger than 2/1, many functional groups capable of reacting with unreacted epoxy groups remain, which is not preferable in terms of electrical insulation performance. For example, it can be mentioned as a functional group in which a carboxyl group reacts with an epoxy group 1: 1.

（式中、Ｒ^１は、炭素数３〜１８のアルキレン基を表し、ｎは１以上の整数を表す。）One of the essential components of the composition of the present invention (I), a polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) reacts with an epoxy group in the molecule. If it is a polyurethane which has a functional unit and the structural unit shown by Formula (1), there will be no restriction | limiting in particular.

(In the formula, R ¹ represents an alkylene group having 3 to 18 carbon atoms, and n represents an integer of 1 or more.)

In formula (1), R ¹ represents an alkylene group having 3 to 18 carbon atoms. In the case of an alkylene group having 2 or less carbon atoms, the water resistance of the resulting polyurethane cannot be kept sufficiently, which is not preferable. Further, in the case of an alkylene group having 19 or more carbon atoms, the type of solvent capable of dissolving the generated polyurethane may be extremely reduced, or adhesion to polyimide may be lowered, which is not preferable. .
n is preferably an integer of 1 to 20.

  The structural unit of the formula (1) is a structural unit derived from a (poly) carbonate diol raw material having a diol structural unit having 3 to 18 carbon atoms. In order to further increase the water resistance, the dimer diol is combined with an epoxy group. It can be preferably used as one component when producing a polyurethane having a functional group capable of reacting and having a structural unit represented by the formula (1). The raw material (poly) carbonate diol having a number average molecular weight of 400 to 10,000 can be used.

  In addition, the expression “(poly) carbonate” in the (poly) carbonate diol described in the present specification means that the molecule has one or more carbonate bonds. In other words, “(poly) carbonate” means both monocarbonate and polycarbonate. Therefore, “(poly) carbonate diol” described in the present specification means a compound having one or more carbonate bonds in the molecule and two alcoholic hydroxyl groups.

In addition, when the (poly) carbonate diol is produced, the raw material diol component may remain and be included. In the present specification, the remaining diol component is referred to as “(poly) carbonate diol”. It is defined as not included.
For example, when (poly) carbonate diol is produced by transesterification using 1,9-nonanediol and diethyl carbonate as raw materials in the presence of a catalyst, the raw material 1,9-nonanediol is a product. When 5 mass% remains in a certain (poly) carbonate diol, it means that the remaining 1,9-nonanediol is not included in the “(poly) carbonate diol”.

  Examples of functional groups capable of reacting with epoxy groups include amino groups, carboxyl groups, carboxylic anhydride groups, mercapto groups, isocyanato groups, and hydroxyl groups. Among these functional groups, the reaction rate with the epoxy group-containing compound having a tricyclodecane structure is preferably within a certain range. From this, a carboxyl group and a carboxylic anhydride group are preferable. Further, it is desirable in use that the functional group is stable in the odor of the compound or in a normal atmosphere in a normal temperature atmosphere. In view of this, a carboxyl group is most desirable.

  In order to suppress warping during curing of the composition of the present invention (I), the increase in the crosslinking density during curing should be smaller unless the solvent resistance, long-term electrical insulation properties, and heat resistance of the cured product are impaired. desirable. In order to suppress the increase in the cross-linking density during curing to some extent and to exhibit the solvent resistance, long-term electrical insulation properties, and heat resistance of the cured product, it has a functional group that can react with an epoxy group and is represented by the formula (1 The polyurethane having the structural unit represented by () preferably has at least one structure in the molecule among the following three structures.

First, one of them is that a polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) further has an imide structure. That is, a polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) has a functional unit capable of reacting with an epoxy group and represented by the formula (1). It is desirable to be a polyurethane polyimide having an imide bond.
It is desirable that the following one structure has a certain branched structure in the molecule as long as it is soluble in the solvent.
Another structure is a polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1), and further containing an organic residue derived from dimer diol. desirable.

  First, a polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by formula (1) has a functional unit capable of reacting with an epoxy group and represented by formula (1). A case of polyurethane polyimide having an imide bond is described.

  Examples of polyurethane polyimide having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) and further having an imide bond include, for example, JP-A-2003-198105 and JP-A-2006. Examples thereof include a polyurethane polyimide having a functional group capable of reacting with an epoxy group described in Japanese Patent No. -307183, a structural unit represented by the formula (1), and further having an imide bond.

  First, a polyurethane polyimide having a functional group capable of reacting with an epoxy group described in JP-A-2003-198105, having a structural unit represented by formula (1), and further having an imide bond will be described.

（式中、複数個のＲ^４は、それぞれ独立に炭素数３〜１８のアルキレン基であり、複数個のＲ^５は、それぞれ独立に炭素数３〜１８のアルキレン基であり、ａ及びｂは、それぞれ独立に１〜２０の整数であり、複数個のＸ^２は、それぞれ独立に２価の有機基である。）

（式中、複数個のＲ^６は、それぞれ独立に炭素数３〜１８のアルキレン基であり、複数個のＲ^７は、それぞれ独立に炭素数３〜１８アルキレン基であり、ｃ及びｄは、それぞれ独立に１〜２０の整数であり、複数個のＸ^３は、それぞれ独立に２価の有機基であり、Ｙ^２は、ＣＨ_２、ＳＯ_２またはＯである。）

A polyurethane polyimide having a functional group capable of reacting with an epoxy group described in JP-A No. 2003-198105 and having a structural unit represented by the formula (1) and further having an imide bond is represented by the following formula ( 4) to polyurethane polyimide having a structural unit represented by formula (6) in the molecule.

(In the formula, a plurality of R ⁴ are each independently an alkylene group having 3 to 18 carbon atoms, a plurality of R ⁵ are each independently an alkylene group having 3 to 18 carbon atoms, and a and b are And each independently represents an integer of 1 to 20, and a plurality of X ² are each independently a divalent organic group.)

(Wherein a plurality of R ⁶ are each independently an alkylene group having 3 to 18 carbon atoms, a plurality of R ⁷ are each independently an alkylene group having 3 to 18 carbon atoms, and c and d are Each independently represents an integer of 1 to 20, a plurality of X ³ are each independently a divalent organic group, and Y ² is CH ₂ , SO ₂ or O.)

In the formula, a plurality of R ⁸ are each independently an alkylene group having 3 to 18 carbon atoms, a plurality of R ⁹ are each independently an alkylene group having 3 to 18 carbon atoms, and e and f are Each independently represents an integer of 1 to 20, a plurality of X ⁴ are each independently a divalent organic group, and Y ³ is any one of the following formulas (7) to (33): .

  The polyurethane polyimide having the structure represented by formula (4) or formula (5) is usually one or more compounds selected from trivalent polycarboxylic acids having acid anhydride groups and derivatives thereof, and isocyanate compounds or amines. Obtained by reacting with a compound.

（式中、Ｒ^１４は、水素、炭素数１〜１０のアルキル基又はフェニル基を示す。）The trivalent polycarboxylic acid having an acid anhydride group and its derivative are not particularly limited. For example, in the case of a polyurethane polyimide having a structure represented by the formula (4), a compound represented by the formula (39) is used. Can be used. Trimellitic anhydride is particularly preferable from the viewpoint of heat resistance and cost.

(In the formula, R ¹⁴ represents hydrogen, an alkyl group having 1 to 10 carbon atoms, or a phenyl group.)

（式中、Ｒ^１５は、水素、炭素数１〜１０のアルキル基又はフェニル基を示し、Ｙ^２は、ＣＨ_２、ＣＯ、ＳＯ_２、またはＯである。）Moreover, in the case of the polyurethane polyimide which has a structure shown by Formula (5), the compound shown by Formula (40) can be used.

(In the formula, R ¹⁵ represents hydrogen, an alkyl group having 1 to 10 carbon atoms, or a phenyl group, and Y ² represents CH ₂ , CO, SO ₂ , or O.)

（式中、Ｙ^３は、前記の式（７）〜式（３３）のいずれかの基である。）Furthermore, in the case of the polyurethane polyimide having the structure represented by the formula (6), a compound represented by the formula (41) can be used.

(In the formula, Y ³ is any one of the above formulas (7) to (33).)

  These tetracarboxylic dianhydrides may be used alone or in combination of two or more.

  In addition to these, as necessary, an aliphatic dicarboxylic acid (succinic acid, glutaric acid, adipic acid, azelaic acid, suberic acid, sebacic acid, decanedioic acid, dodecanedioic acid, dimer acid, etc.) Aromatic dicarboxylic acids (isophthalic acid, terephthalic acid, phthalic acid, naphthalenedicarboxylic acid, oxydibenzoic acid, etc.) can be used in combination. In this case, an amide bond is also formed in the molecular chain.

（式中、複数個のＲ^１６は、それぞれ独立に炭素数３〜１８のアルキレン基であり、複数個のＲ^１７は、それぞれ独立に炭素数３〜１８のアルキレン基であり、ｈ及びｉは、それぞれ独立に１〜２０の整数であり、複数個のＸ^５は、それぞれ独立に２価の有機基である。）As the isocyanate compound, for example, a diisocyanate compound represented by the formula (42) can be used.

(Wherein a plurality of R ¹⁶ are each independently an alkylene group having 3 to 18 carbon atoms, a plurality of R ¹⁷ are each independently an alkylene group having 3 to 18 carbon atoms, and h and i are And each independently represents an integer of 1 to 20, and the plurality of X ⁵ are each independently a divalent organic group.)

（式中、複数個のＲ^１８は、それぞれ独立に炭素数３〜１８のアルキレン基であり、ｊは、１〜２０の整数である。）

（式中、Ｘ^６は、２価の有機基である。）The diisocyanate compound of the formula (42) can be obtained by reacting the (poly) carbonate diol represented by the formula (43) with the diisocyanate represented by the formula (44).

(In the formula, a plurality of R ¹⁸ are each independently an alkylene group having 3 to ¹⁸ carbon atoms, and j is an integer of 1 to 20).

(In the formula, X ⁶ is a divalent organic group.)

X ⁶ of the diisocyanate represented by the formula (44) is, for example, an alkylene group having 1 to 20 carbon atoms, or a phenylene group that is unsubstituted or substituted with a lower alkyl group having 1 to 5 carbon atoms such as a methyl group. An arylene group is mentioned. The number of carbon atoms of the alkylene group is more preferably 1-18. A group having two aromatic rings such as diphenylmethane-4,4′-diyl group and diphenylsulfone-4,4′-diyl group is also preferable.

  Examples of the (poly) carbonate diol represented by the above formula (43) include α, ω-poly (1,6-hexylene carbonate) diol, α, ω-poly (3-methyl-1,5-pentyl). Lencarbonate) diol, α, ω-poly [(1,6-hexylene: 3-methyl-pentamethylene) carbonate] diol, α, ω-poly [(1,9-nonylene: 2-methyl-1,8- Octylene) carbonate] diol and the like, and commercially available products are trade names PLACEL, CD-205, 205PL, 205HL, 210, 210PL, 210HL, 220, 220PL, 220HL, manufactured by Daicel Chemical Industries, Ltd. Product names Kuraray Polyol C-590, C-1065N, C-1015N, C-2015N etc. It is done. These can be used alone or in combination of two or more.

As described above, when the (poly) carbonate diol is produced, the diol component as the raw material may remain and be contained. It is defined as not included in “carbonate diol”.
Accordingly, trade names PLACEL, CD-205, 205PL, 205HL, 210, 210PL, 210HL, 220, 220PL, 220HL, manufactured by Daicel Chemical Industries, Ltd. Raw material diols contained in commercially available (poly) carbonate diols such as C-1015N and C-2015N are not included in “(poly) carbonate diols”. These raw material diol components are included in (w) described later.

Examples of the diisocyanate represented by the formula (44) include diphenylmethane-2,4'-diisocyanate;3,2'-,3,3'-,4,2'-,4,3'-5, , 2'-, 5,3'-, 6,2'- or 6,3'-dimethyldiphenylmethane-2,4'-diisocyanate;3,2'-,3,3'-,4,2'-,4,3'-,5,2'-,5,3'-,6,2'- or 6,3'-diethyldiphenylmethane-2,4'-diisocyanate;3,2'-,3,3'-4,2'-,4,3'-,5,2'-,5,3'-,6,2'- or 6,3'-dimethoxydiphenylmethane-2,4'-diisocyanate; diphenylmethane-4, 4'-diisocyanate;diphenylmethane-3,3'-diisocyanate;-3,4'-diisocyanate; diphenyl ether-4,4'-diisocyanate;benzophenone-4,4'-diisocyanate;diphenylsulfone-4,4'-diisocyanate;tolylene-2,4-diisocyanate; tolylene-2,6 M-xylylene diisocyanate; p-xylylene diisocyanate; naphthalene-2,6-diisocyanate; in formula (44) such as 4,4 '-[2,2-bis (4-phenoxyphenyl) propane] diisocyanate , X ⁶ is preferably an aromatic polyisocyanate having an aromatic ring. These can be used alone or in combination of two or more.

  In addition, as the diisocyanate represented by the formula (44), within the scope of the object of the present invention, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, isophorone diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, trans Aliphatic or alicyclic isocyanates such as cyclohexane-1,4-diisocyanate, hydrogenated m-xylylene diisocyanate, and lysine diisocyanate, or trifunctional or higher polyisocyanates can be used.

  As the diisocyanate represented by the formula (44), a diisocyanate stabilized with a blocking agent necessary for avoiding changes over time may be used. Examples of the blocking agent include alcohol, phenol and oxime, but there is no particular limitation.

  As a raw material of this polyurethane polyimide, a diol component (hereinafter referred to as component (w)) other than the (poly) carbonate diol represented by the formula (43) can be used as necessary.

Examples of the component (w) include 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, and 1,5-pentanediol. 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,8-octanediol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,9-nonanediol, 2 -Methyl-1,8-octanediol, 1,10-decamethylene glycol, 1,2-tetradecanediol, 2,4-diethyl-1,5-pentanediol, 2-butyl-2-ethylpropanediol, 1, Examples include 3-cyclohexanedimethanol, 1,3-xylylene glycol, and 1,4-xylylene glycol.
Moreover, the raw material diol contained in the above-mentioned commercially available (poly) carbonate diol is contained in this component (w).

  The blending amount of the (poly) carbonate diol and component (w) represented by the above formula (43) and the diisocyanate represented by the formula (44) is such that the ratio of the number of hydroxyl groups to the number of isocyanate groups is isocyanate group / hydroxyl group = 1.01. It is preferable to make it above.

  The reaction of the (poly) carbonate diol represented by the above formula (43) and the component (w) with the diisocyanate represented by the formula (44) can be carried out without solvent or in the presence of an organic solvent. The reaction temperature is preferably 60 to 200 ° C, more preferably 80 to 180 ° C. The reaction time can be appropriately selected depending on the scale of the batch, the reaction conditions employed, and the like. For example, it can be 2 to 5 hours on a 1 to 5 L flask scale.

  The number average molecular weight of the diisocyanate compound represented by the formula (42) thus obtained is preferably 500 to 10,000, more preferably 1,000 to 9,500, and 1,500 to Particularly preferred is 9,000. When the number average molecular weight is less than 500, the warping property tends to be deteriorated. When the number average molecular weight exceeds 10,000, the reactivity of the isocyanate compound is lowered, and it tends to be difficult to obtain a polyimide resin.

  In the present specification, the number average molecular weight is a value measured by gel permeation chromatography (GPC) and converted using a standard polystyrene calibration curve.

Polyisocyanate compounds other than the diisocyanate compound represented by the formula (42) can also be used as the isocyanate compound as the raw material component of the polyurethane polyimide represented by the formulas (4) to (6).
These compounds are not particularly limited as long as they are polyisocyanate compounds other than the diisocyanate compound represented by the formula (42), and examples thereof include diisocyanates represented by the formula (44) and trivalent or higher polyisocyanates. These can be used alone or in combination of two or more. The preferred range of the number average molecular weight of the polyisocyanate compound other than the diisocyanate compound represented by the formula (42) is the same as that of the diisocyanate compound represented by the formula (42).

  In particular, from the viewpoint of heat resistance, it is preferable to use a diisocyanate compound represented by the formula (42) and a polyisocyanate compound other than the diisocyanate compound represented by the formula (42) in combination. In addition, when using individually the polyisocyanate compounds other than the diisocyanate compound represented by the formula (42) and the diisocyanate compound represented by the formula (42), flexibility, warpage, etc. as a protective film for a flexible wiring board are used. From the viewpoint, it is preferable to use a diisocyanate compound represented by the formula (42).

As a polyisocyanate compound other than the diisocyanate compound represented by the formula (42), 50 to 100% by mass of the total amount is preferably an aromatic polyisocyanate, and a balance of heat resistance, solubility, mechanical properties, cost and the like. , 4,4'-diphenylmethane diisocyanate is particularly preferred.

  When a diisocyanate compound represented by the formula (42) and a polyisocyanate compound other than the diisocyanate compound represented by the formula (42) are used in combination, a diisocyanate compound represented by the formula (42) / a compound other than the diisocyanate compound represented by the formula (42) The equivalent ratio of the polyisocyanate compound is preferably 0.1 / 0.9 to 0.9 / 0.1, more preferably 0.2 / 0.8 to 0.8 / 0.2, It is especially preferable to set it as 0.3 / 0.7-0.7 / 0.3. When the equivalence ratio is within this range, film properties such as good warpage, adhesion and good heat resistance can be obtained.

  Examples of the amine compound as a raw material component of the polyurethane polyimide having the structural units represented by the formulas (4) to (6) include compounds obtained by converting the isocyanate group in the isocyanate compound into an amino group. Conversion of the isocyanato group to an amino group can be performed by a known method. A preferred range of the number average molecular weight of the amine compound is the same as that of the diisocyanate compound represented by the formula (42).

  Moreover, the trivalent polycarboxylic acid which has the acid anhydride group of the raw material component of the polyurethane polyimide which has a structural unit shown by Formula (4)-Formula (6), or its derivative (s), and / or the tetravalence which has an acid anhydride group. The blending ratio of the polycarboxylic acid is such that the carboxyl group and the acid anhydride are based on the total number of isocyanate groups of the isocyanate compound (the diisocyanate compound represented by the formula (42) and the polyisocyanate compound other than the diisocyanate compound represented by the formula (42)). The ratio of the total number of physical groups is preferably 0.6 to 1.4, more preferably 0.7 to 1.3, and 0.8 to 1.2. It is particularly preferable to do so. When this ratio is less than 0.6 or exceeds 1.4, it tends to be difficult to increase the molecular weight of the resin containing polyimide bonds.

（式中、Ｒ^４、Ｒ^５、ａ、ｂ、Ｘ^２は、前記のとおりである。）In addition, a trivalent polycarboxylic acid having an acid anhydride group or a derivative thereof and / or a tetravalent polycarboxylic acid having an acid anhydride group is a compound represented by the formula (39), and an isocyanate compound is represented by the formula (42). When the diisocyanate compound shown is used, a polyamideimide having a structural unit represented by the formula (4) can be obtained.

(Wherein R ⁴ , R ⁵ , a, b, and X ² are as described above.)

（式中、Ｒ^６、Ｒ^７、ｃ、ｄ、Ｘ^３、Ｙ^２は、前記のとおりである。）In addition, a trivalent polycarboxylic acid having an acid anhydride group or a derivative thereof and / or a tetravalent polycarboxylic acid having an acid anhydride group, a compound represented by the formula (40), and an isocyanate compound represented by the formula (42) When the diisocyanate compound shown is used, a polyamideimide having a structural unit represented by the formula (5) can be obtained.

(Wherein R ⁶ , R ⁷ , c, d, X ³ and Y ² are as described above.)

（式中、Ｒ^８、Ｒ^９、ｅ、ｆ、Ｘ^４、Ｙ^３は、前記のとおりである。）Further, a trivalent polycarboxylic acid having an acid anhydride group or a derivative thereof and / or a tetravalent polycarboxylic acid having an acid anhydride group as a compound represented by the formula (41), an isocyanate compound represented by the formula (42) When the diisocyanate compound shown is used, a polyamideimide having a structural unit represented by the formula (6) can be obtained.

(In the formula, R ⁸ , R ⁹ , e, f, X ⁴ , and Y ³ are as described above.)

A trivalent polycarboxylic acid having an acid anhydride group and a derivative thereof, and a tetravalent polycarboxylic acid having an acid anhydride group in a method for producing a polyurethane polyimide having a structural unit represented by formula (4) to formula (6) The reaction of one or more compounds selected from acids with an isocyanate compound or an amine compound can be carried out by heat condensation in the presence of a solvent while removing the carbon dioxide gas that is generated free from the reaction system. .
By this method, a polyurethane polyimide having a carboxyl group, an acid anhydride or an isocyanate group at the terminal can be produced. The terminal group is preferably a carboxyl group and / or an acid anhydride in consideration of reactivity with the epoxy group.

  As the solvent for synthesis, a solvent having a boiling point of 150 ° C. to 250 ° C. under atmospheric pressure is generally used. In order to balance the solubility of the polyurethane polyimide having the structural units represented by the formulas (4) to (6) and the volatility of the solvent, 2 solvents having a boiling point of 150 ° C. to 250 ° C. under atmospheric pressure are used. More than one type can be used in combination and is preferred. More preferably, a solvent having a boiling point of 170 ° C. or more and less than 200 ° C. under atmospheric pressure and a solvent having a boiling point of 200 ° C. to 220 ° C. under atmospheric pressure are used in combination.

  Examples of the solvent having a boiling point of 170 ° C. or higher and lower than 200 ° C. under atmospheric pressure include diethylene glycol dimethyl ether (boiling point 162 ° C.), diethylene glycol diethyl ether (boiling point 189 ° C.), diethylene glycol ethyl methyl ether (boiling point 176 ° C.), dipropylene glycol. -Ludimethyl ether (boiling point 171 ° C.), 3-methoxybutyl acetate (boiling point 171 ° C.), ethylene glycol monobutyl ether acetate (boiling point 192 ° C.) and the like.

  Examples of the solvent having a boiling point of 200 ° C. to 220 ° C. under atmospheric pressure include diethylene glycol butyl methyl ether (boiling point 212 ° C.), tripropylene glycol dimethyl ether (boiling point 215 ° C.), triethylene glycol dimethyl ether (boiling point 216 ° C.), ethylene Examples include glycol dibutyl ether (boiling point 203 ° C.), diethylene glycol monoethyl ether acetate (boiling point 217 ° C.), and γ-butyrolactone (boiling point 204 ° C.).

After synthesis, it is preferable to use a suitable solvent for the thermosetting composition of the present invention as it is. In order to carry out the reaction in a homogeneous system with high volatility and low temperature curability, the following combinations of solvents are preferable.
Specifically, as a solvent having a boiling point of 170 ° C. to 200 ° C. under atmospheric pressure, diethylene glycol diethyl ether (boiling point 189 ° C.), diethylene glycol ethyl methyl ether (boiling point 176 ° C.), dipropylene glycol dimethyl ether (boiling point 171 ° C. ) And a solvent having a boiling point of 200 ° C. to 220 ° C. under atmospheric pressure, preferably γ-butyrolactone (boiling point 204 ° C.), and most preferable combination is atmospheric pressure. Combining diethylene glycol diethyl ether (boiling point 189 ° C.) as a solvent having a boiling point of 170 ° C. to 200 ° C. and γ-butyrolactone (boiling point 204 ° C.) as a solvent having a boiling point of 200 ° C. to 220 ° C. under atmospheric pressure. It is.

  Use of a combination of these preferable solvents is preferable because it has a low hygroscopic property, a high boiling point, and a low volatility, and is therefore excellent as a solvent for screen printing ink.

  In order to fully express the above effect, the ratio of the solvent having a boiling point of 170 ° C. to 200 ° C. under atmospheric pressure and the solvent having a boiling point of 200 ° C. to 220 ° C. under atmospheric pressure is a mass ratio, It is in the range of 5:95 to 80:20, and more preferably in the range of 10:90 to 60:40.

  In addition, a solvent other than a solvent having a boiling point of 170 ° C. to 200 ° C. under atmospheric pressure and a solvent having a boiling point of 200 ° C. to 220 ° C. under atmospheric pressure is used in combination as long as the solubility of the polyurethane polyimide is not impaired. can do. Reactive monomers and reactive diluents can also be used as solvents.

  It is preferable that the usage-amount of a solvent shall be 0.8 to 5.0 times (mass ratio) of the polyurethane polyimide to produce | generate. If it is less than 0.8 times, the viscosity at the time of synthesis is too high, and the synthesis tends to be difficult due to the inability to stir. If it exceeds 5.0 times, the reaction rate tends to decrease.

  The reaction temperature is preferably 80 to 210 ° C, more preferably 100 to 190 ° C, and particularly preferably 120 to 180 ° C. If it is less than 80 ° C., the reaction time becomes too long. The reaction time can be appropriately selected depending on the scale of the batch and the reaction conditions employed. If necessary, the reaction may be performed in the presence of a catalyst such as a tertiary amine, an alkali metal, an alkaline earth metal, a metal such as tin, zinc, titanium, cobalt, or a metalloid compound.

The number average molecular weight of the polyurethane polyimide thus obtained is preferably 4,000 to 40,000, more preferably 5,000 to 38,000, and 6,000 to 36,000. It is particularly preferred. When the number average molecular weight is less than 4,000, film properties such as heat resistance tend to be lowered. In addition, workability tends to be inferior.
In addition, the isocyanate group at the end of the resin can be blocked with a blocking agent such as alcohols, lactams, or oximes after completion of the synthesis.

  Next, a polyurethane polyimide having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) and further having an imide bond described in JP-A-2006-307183 will be described.

（式中、Ｒ^２、Ｒ^３は、それぞれ独立に、２価の脂肪族または芳香族炭化水素基を示し、Ｙ^１はテトラカルボン酸またはその酸無水物基から誘導される４価の有機基を示し、Ｘ^１はジアミン或いはジイソシアネートから誘導される２価の有機基を示し、ｍは、０〜２０の整数である。）JP-A 2006-307183 discloses a polyurethane polyimide having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1), and further having an imide bond. ), The component (b), the component (c ′) and the component (d).
Component (a) diisocyanate,
Component (b) (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms,
Component (c ′) A diol compound having a functional group capable of reacting with an epoxy group, and Component (d) a bifunctional hydroxyl-terminated imide represented by the formula (3).

Wherein R ² and R ³ each independently represents a divalent aliphatic or aromatic hydrocarbon group, and Y ¹ represents a tetravalent organic group derived from a tetracarboxylic acid or an acid anhydride group thereof. X ¹ represents a divalent organic group derived from diamine or diisocyanate, and m is an integer of 0 to 20.)

  Any diisocyanate may be used 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 Range diisocyanate - DOO, tolidine diisocyanate - DOO, xylylene diisocyanate - DOO etc. can be preferably exemplified.

As the diisocyanate, a blocked diisocyanate in which an isocyanate group is blocked with a blocking agent can be used.
Examples of the blocking agent include alcohols, phenols, active methylenes, mercaptans, acid amides, acid imides, imidazoles, ureas, oximes, amines, imines, There are bisulfite type, pyridine type, etc., and these may be used alone or in combination. Specific blocking agents include alcohols such as methanol, ethanol, propanol, butanol, 2-ethylhexanol, methyl cellosolve, butyl cellosolve, methyl carbitol, benzyl alcohol, Cyclohexanol, etc., phenolic, phenol, cresol, ethyl phenol, butyl phenol, nonyl phenol, dinonyl phenol, styrenated phenol, hydroxybenzoate, etc., active methylene As systems, dimethyl malonate, diethyl malonate, methyl acetoacetate, ethyl acetoacetate, acetylacetone, etc., as mercaptans, as butyl mercaptan, dodecyl mercaptan, etc., as acid amides, as acetanilide, acetate amide, ε-caprolactam, δ-valero Lactam, γ-Butirola Tam, etc., acid imide, succinimide, maleic imide, imidazole, imidazole, 2-methylimidazole, urea, urea, thiourea, ethylene urea, etc., oxime, Formaldehyde oxime, acetoaldoxime, acetoxime, methyl ethyl ketoxime, cyclohexanone oxime, etc., amine type, diphenylamine, aniline, carbazole, etc., imine type, ethyleneimine, polyethyleneimine, etc., bisulfite type, bisulfite type Examples of pyridines such as 2-hydroxypyridine and 2-hydroxyquinoline.

  The (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms has an effect of imparting flexibility to a target polyurethane polyimide.

  The (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms 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 (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms is specifically UH-CARB, UN-CARB, UD-CARB, UC-CARB, Daicel manufactured by Ube Industries, Ltd. Suitable examples include PLACEL CD-PL, PLACEL CD-H manufactured by Chemical Industry Co., Ltd., and Kuraray polyol C series manufactured by Kuraray Co., Ltd. These polycarbonate polyols are used alone or in combination of two or more.

In addition, when the (poly) carbonate polyol is produced, the polyol component as a raw material may remain and be included. In the present specification, the remaining polyol component is referred to as “(poly) carbonate polyol”. It is defined as not included.
For example, when (poly) carbonate polyol is produced by transesterification using 1,9-nonanediol and diethyl carbonate as raw materials in the presence of a catalyst, the raw material 1,9-nonanediol is a product. When 5% by mass remains in a certain (poly) carbonate polyol, the remaining 1,9-nonanediol is not included in the “(poly) carbonate polyol”, but the component (x ).

  As a raw material of this polyurethane polyimide, a (poly) carbonate polyol having an organic residue derived from one kind of diol having 3 to 18 carbon atoms may be used, or two or more kinds may be used in combination.

  By introducing a diol compound having a functional group capable of reacting with an epoxy group into the polyurethane polyimide molecule, it is possible to effectively crosslink the polyurethane polyimide, and the resulting cured insulating film has heat resistance. And the solvent resistance can be further increased.

  The diol compound having a functional group capable of reacting with such an epoxy group is not particularly limited, but 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. In particular, a diol compound having a carboxyl group is preferred.

  Of the compounds having a carboxyl group or a phenolic hydroxyl group as a substituent, a diol compound having 1 to 30 carbon atoms is preferred, and a diol compound having 2 to 20 carbon atoms is more preferred. Specifically, examples of the diol compound having a phenolic hydroxyl group include 2,6-bis (hydroxymethyl) -phenol and 2,6-bis (hydroxymethyl) -p-cresol, which have a carboxyl group. Examples of the diol compound include 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, and 2,2-dimethylolbutyric acid.

（式中、Ｒ^２、Ｒ^３は、それぞれ独立に、２価の脂肪族または芳香族炭化水素基を示し、Ｙ^１はテトラカルボン酸またはその酸無水物基から誘導される４価の有機基を示し、Ｘ^１はジアミン或いはジイソシアネートから誘導される２価の有機基を示し、ｍは、０〜２０の整数である。）Used when synthesizing a polyurethane polyimide having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) and further having an imide bond, as described in JP-A-2006-307183. The bifunctional hydroxyl-terminated imide can be represented by the following formula (3).

Wherein R ² and R ³ each independently represents a divalent aliphatic or aromatic hydrocarbon group, and Y ¹ represents a tetravalent organic group derived from a tetracarboxylic acid or an acid anhydride group thereof. X ¹ represents a divalent organic group derived from diamine or diisocyanate, and m is an integer of 0 to 20.)

  This bifunctional hydroxyl-terminated imide is obtained from a tetracarboxylic acid component and an amine component composed of a diamine compound and a monoamine compound having one hydroxyl group. In formula (3), m shows the integer of 0-20, Preferably it is 0-10, More preferably, it is 0-5, Most preferably, it is 1-5. When m is 20 or more, the bending resistance of the obtained insulating film may be deteriorated.

The tetracarboxylic acid component that is a raw material component of the bifunctional hydroxyl-terminated imide is an aromatic tetracarboxylic acid, or an esterified product of an acid dianhydride or lower alcohol thereof, and the resulting polyurethane polyimide has excellent heat resistance. Therefore, it is preferable. Specifically, 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′-diphenylsulfone tetracarboxylic acid, 3,3 ′, 4,4′-benzophenone tetracarboxylic 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-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 1,2,4,5-naphthalenetetracarboxylic acid, 1, , 5,8-naphthalenetetracarboxylic acid, aromatic tetracarboxylic acids such as 1,1-bis (2,3-dicarboxyphenyl) ethane, or esterified products of their acid dianhydrides and lower alcohols, and Cycloaliphatic tetracarboxylic acids such as cyclopentanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, 3-methylcyclohexane-1,2,4,5-tetracarboxylic acid, or their acids Preferable examples include anhydrides and esterified products of lower alcohols. Of these, 2,3,3 ′, 4′-biphenyltetracarboxylic acid, 3,3 ′, 4,4′-diphenylethertetracarboxylic acid, and 2,2 ′, 3,3′-biphenyl are particularly preferred. Tetracarboxylic acids or their acid dianhydrides or esterified products of lower alcohols are preferred because they have excellent solubility in solvents when used as polyurethane polyimides.
The tetracarboxylic acid component is preferably a tetracarboxylic dianhydride that can be easily reacted with a diamine.

  The diamine compound in the amine component used as a raw material for the bifunctional hydroxyl-terminated imide is not particularly limited, and aromatic, alicyclic and aliphatic diamines can be used. Specifically, the aromatic diamine is one benzene ring such as 1,4-diaminobenzene, 1,3-diaminobenzene, 2,4-diaminotoluene, 1,4-diamino-2,5-dihalogenobenzene. -Containing diamines, bis (4-aminophenyl) ether, bis (3-aminophenyl) ether, bis (4-aminophenyl) sulfone, bis (3-aminophenyl) sulfone, bis (4-amino) Phenyl) methane, bis (3-aminophenyl) methane, bis (4-aminophenyl) sulfide, bis (3-aminophenyl) sulfide, 2,2-bis (4-aminophenyl) propane, 2,2-bis ( 3-aminophenyl) propane, 2,2-bis (4-aminophenyl) hexafluoropropane, o-dianisidine, o-tolidine, torigins Diamines containing two benzene rings such as phonic 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, Diamines containing three benzene rings such as 3-diisopropylbenzene, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexa Fluoropropane, 2,2-bis [4- (4-aminophenoxy) phenyl] sulfone, 4,4 '-(4-aminophenoxy) biphenyl, 9,9-bis (4-a Examples thereof include diamine compounds such as diamines containing four or more benzene rings such as minophenyl) fluorene and 5,10-bis (4-aminophenyl) anthracene. The alicyclic diamine is preferably an alicyclic diamine having 5 to 30 carbon atoms having one or more aliphatic rings in the molecule, such as isophorone diamine, norbornene diamine, 1,2-diaminocyclohexane, 1,3-diamino. Examples include cyclohexane, 1,4-diaminocyclohexane, bis (4-aminocyclohexyl) methane, and the like. The aliphatic diamine is preferably an aliphatic diamine having 2 to 30 carbon atoms, and examples thereof include hexamethylene diamine and diaminododecane.

Among the diamine compounds, a bifunctional hydroxyl-terminated imide using an alicyclic diamine has high solubility in a solvent. For this reason, even when R ^{18 in the} formula (43) is combined with a (poly) carbonate polyol comprising a long chain methylene group having 9 to ¹⁸ carbon atoms, the polyurethane polyimide is uniformly distributed in the solvent. It is particularly suitable because it is easily dissolved and has good heat resistance.

  The monoamine compound having one hydroxyl group in the amine component of the bifunctional hydroxyl-terminated imide is not particularly limited as long as it is a compound having one hydroxyl group and one amino group in the molecule. Aliphatic monoamine compounds having a hydroxyl group such as propanol and aminobutanol, in particular aliphatic monoamine compounds having a hydroxyl group having 1 to 10 carbon atoms, alicyclic monoamine compounds having a hydroxyl group such as aminocyclohexanol, particularly 3 to 3 carbon atoms Fragrance having a hydroxyl group such as an alicyclic monoamine compound having 20 hydroxyl groups, aminophenol, aminocresol, 4-hydroxy-4'-aminodiphenyl ether, 4-hydroxy-4'-aminobiphenyl, aminobenzyl alcohol, aminophenethyl alcohol, etc. Group monoamination Things, especially carbon atoms can be preferably exemplified an aromatic monoamine compound having 6-20 hydroxyl groups.

  The bifunctional hydroxyl-terminated imide 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 of the tetracarboxylic acid component (or two adjacent carboxyl groups, etc. ) And the number of equivalents of the amino group of the amine component so as to be substantially equal to each other, polymerization and imidization reaction can be performed in a 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 less, particularly 80 ° C. or less. Then, the amide-acid oligomer (also referred to as an 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. for dehydration / imide 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 solvent used in producing the bifunctional hydroxyl-terminated imide include amides such as N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, and N-methylcaprolactam. Solvents, dimethyl sulfoxide, hexamethylphosphamide, dimethylsulfone, tetramethylenesulfone, dimethyltetramethylenesulfone-containing solvents such as sulfur atoms, cresol, phenol, xylenol and other phenolic solvents, diethylene glycol dimethyl ether (diglyme), triethylene Glycol solvents such as glycol dimethyl ether (triglyme) and tetraglyme, lactone solvents such as γ-butyrolactone, isophorone, cyclohexanone, 3,3,5-trimethylcyclohexane Ketones solvents such Sanon, pyridine, ethylene glycol, dioxane, and other solvents such as tetramethylurea and benzene optionally toluene, aromatic hydrocarbon solvents such as xylene. These organic solvents may be used alone or in combination of two or more.

  The bifunctional hydroxyl-terminated imide produced as described above may be a mixture of a plurality of bifunctional hydroxyl-terminated imides having different m in the formula (3). In the present invention, a mixture of a plurality of bifunctional hydroxyl-terminated imide oligomers having different m may be used separately for each polyimide, but can be suitably used as it is without being separated. In addition, m (average value of m in the case of a mixture) of bifunctional hydroxyl-terminated imides 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 addition, the bifunctional hydroxyl-terminated imide produced as described above may be used as a modified imide oligomer solution by directly or concentrating or diluting the reaction solution. Alternatively, the reaction solution may be poured into a non-soluble solvent such as water and isolated as a powdered product, and the powder product may be dissolved in a solvent and used when necessary.

This polyurethane polyimide, as mentioned above,
Component (a) diisocyanate,
Component (b) (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms,
Component (c ′) Obtained by reacting a diol compound having a functional group capable of reacting with an epoxy group, and a component (d) a composition having a bifunctional hydroxyl-terminated imide represented by formula (3) as essential components.

  Moreover, the polyol which does not belong to any of a component (b), a component (c '), and a component (d) can be used together as needed (Hereinafter, this component is described as a component (x).).

  Examples of the component (x) include 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, and 1,5-pentanediol. 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,8-octanediol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,9-nonanediol, 2 -Methyl-1,8-octanediol, 1,10-decamethylene glycol, 1,2-tetradecanediol, 2,4-diethyl-1,5-pentanediol, 2-butyl-2-ethylpropanediol, 1, Examples include 3-cyclohexanedimethanol, 1,3-xylylene glycol, and 1,4-xylylene glycol.

  As described above, when the (poly) carbonate polyol is produced, the polyol component as a raw material may be left and contained, but in this specification, the remaining polyol component is “(poly) It is not included in “carbonate polyol” but included in component (x).

  The composition ratio of each component of component (a), component (b), component (c ′), and component (d) is the total number of hydroxyl groups / isocyanate groups. The molar ratio of component (c ′) + component (d) + component (x)] / component (a) is 0.5 to 3.0, preferably 0.8 to 2.5, especially 0.9 to 2. A ratio of 0.0 is preferred. When there are too many components (a), a polymerization liquid may thicken and it is unpreferable. Furthermore, it is preferable that the molar ratio of [component (b) + component (c ′) + component (x)] / component (d) is 0.01 to 100, preferably 0.1 to 10. This is because too much [component (b) + component (c ′) + component (x)] is inferior in heat resistance, and too much component (d) is inferior in flexibility.

  Further, the combination of the component (b) and the component (c ′), which are raw material components when producing this polyurethane polyimide, is an organic residue derived from a diol having 3 to 18 carbon atoms having a number average molecular weight of 500 to 10,000. When comprising a combination of a (poly) carbonate polyol having a group (component (b)) and component (c ′), component (a), [component (b) + component (c ′) + component (x)], Is a ratio of [component (b) + component (c ′) + component (x)] / component (a) of 0.5 to 2.5, preferably 0.8 to 2.5, In addition, the component (b) and the component (c ′) have a component (c ′) / component (b) molar ratio of 0.1 to 10, preferably 0.1 to 5. . If the value of [component (b) + component (c ′) + component (x)] / component (a) is too small, the content of component (d) increases and the flexibility is inferior, and [component (b) + component If the value of (c ′) + component (x)] / component (a) is too large, the content of component (d) decreases and the heat resistance is inferior. Moreover, in the ratio of component (b) and component (c ′), when the ratio of component (c ′) is too large, the viscosity of the resulting polyurethane polyimide solution becomes too high, or the hygroscopicity of the resulting cured film is high. Since it may become too large, it is not preferable. On the other hand, if the proportion of the component (c ′) is too small, the crosslinking density is lowered, and the heat resistance of the resulting cured film tends to be lowered, which is not preferable. Component (x) is preferably used in a smaller amount than component (b) or component (c ′), and more preferably only the polyol component remaining during the synthesis of component (b) is used.

（式中、Ｘ^６はジイソシアネートからイソシアネート基を除いた２価の基、複数個のＲ^２０は、それぞれ独立に、炭素数３〜１８のジオールから水酸基を除いた２価の基、ｔは１〜４０の整数、ｕは１〜１００の整数を表す。）

（式中、Ｘ^６はジイソシアネートからイソシアネート基を除いた２価の基、Ｗは、エポキシ基と反応可能な官能基を有するジオールから水酸基を除いた２価の基を表し、ｖは１〜４０の整数を表す。）

（式中、Ｘ^６はジイソシアネートからイソシアネート基を除いた２価の基、複数個のＲ^２１、Ｒ^２２はそれぞれ独立に２価の脂肪族または芳香族炭化水素基、Ｙ^４はテトラカルボン酸のカルボキシル基を除いた４価の基、Ｘ^７はジアミンのアミノ基を除いた２価の基を表し、ｗは０〜２０の整数、ｘは１〜１００の整数を表す。）The resulting polyurethane polyimide preferably contains structural units of the following formulas (45) to (47).

(In the formula, X ⁶ is a divalent group obtained by removing an isocyanate group from diisocyanate, a plurality of R ²⁰ are each independently a divalent group obtained by removing a hydroxyl group from a diol having 3 to 18 carbon atoms, and t is 1) Integer of ~ 40, u represents an integer of 1-100.)

(In the formula, X ⁶ represents a divalent group obtained by removing an isocyanate group from diisocyanate, W represents a divalent group obtained by removing a hydroxyl group from a diol having a functional group capable of reacting with an epoxy group, and v represents 1 to 40. Represents an integer.)

(Wherein X ⁶ is a divalent group obtained by removing an isocyanate group from diisocyanate, a plurality of R ²¹ and R ²² are each independently a divalent aliphatic or aromatic hydrocarbon group, and Y ⁴ is a tetracarboxylic acid. A tetravalent group excluding a carboxyl group, X ⁷ represents a divalent group excluding an amino group of diamine, w is an integer of 0 to 20, and x is an integer of 1 to 100.)

  Polyurethane polyimide is a copolymer of a 3 to 18 carbon diol-derived (poly) carbonate unit, a diol unit having a functional group capable of reacting with an epoxy group, and a bifunctional hydroxyl-terminated imide unit via a urethane bond. U, v, and x represent the degree of polymerization and the composition ratio of these units. However, this does not restrictively indicate that the above units are block copolymerized. The (poly) carbonate unit derived from a diol having 3 to 18 carbon atoms, a diol unit having a functional group capable of reacting with an epoxy group, and a bifunctional hydroxyl-terminated imide unit may be block copolymerization or random copolymerization. Moreover, although the terminal is not specified, it is an isocyanate group or a hydroxyl group by the diisocyanate compound or each unit located at the terminal.

  Furthermore, in this method for producing polyurethane polyimide, all components may be dissolved in a solvent at the same time and reacted. Since precipitation is likely to occur, the diisocyanate and (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms are reacted in excess with respect to the hydroxyl group of the isocyanate group, Next, it is preferable to react with a bifunctional hydroxyl-terminated imide because the reaction can be favorably advanced while maintaining solubility.

  When this polyurethane polyimide production method is specifically described, a diisocyanate compound and a (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms or a diol having a functional group capable of reacting with an epoxy group The reaction with can be carried out without solvent or dissolved in a solvent. The reaction temperature is 30 ° C to 150 ° C, preferably 30 ° C to 120 ° C, and the reaction time is usually 1 to 10 hours. This reaction is preferably performed in a nitrogen atmosphere in order to prevent the isocyanate from being deactivated by moisture.

  A diisocyanate compound obtained by a reaction between a diisocyanate compound and a (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms or a diol having a functional group capable of reacting with an epoxy group; The reaction with the hydrophilic hydroxyl-terminated imide can be suitably carried out in a solvent in a nitrogen atmosphere at a reaction temperature of 30 ° C. to 150 ° C., preferably 30 ° C. to 120 ° C., for a reaction time of 1 to 15 hours. In this reaction, the ratio of the number of hydroxyl groups of the bifunctional hydroxyl-terminated imide to the number of isocyanate groups of the diisocyanate compound (number of hydroxyl groups / number of isocyanate groups) is 0.5 to 2.5, preferably 1.5 to 2.5. Preferably it is. If it is 0.5 or less, the heat resistance of the resulting polyurethane polyimide resin is low, and if it is 2.5 or more, it becomes too hard when it is used as a cured film.

  As a solvent that can be suitably used in the reaction for producing this polyurethane polyimide, paragraph [4] as a solvent that can be used in the synthesis of polyurethane polyimide having a structural unit represented by formulas (4) to (6). The solvents described in [0191] to [0197] can be used.

  In order to suitably obtain the thermosetting composition of the present invention, the polyurethane polyimide can be dissolved in a solvent at a high concentration of at least 3% by mass, preferably about 5 to 60% by mass. The solution viscosity at 25 ° C. (E-type rotational viscometer) is preferably 1000 to 10000000 mPa · s, particularly about 1000 to 600000 mPa · s.

  When the molecular weight of this polyurethane polyimide becomes too large, the solution viscosity becomes too high, and stirring becomes difficult during preparation of the composition. Moreover, when the composition becomes too high in viscosity, workability when forming a coating film by a method such as screen printing is lowered. Therefore, the number average molecular weight of the polyurethane polyimide constituting the resin composition of the present invention is preferably 3000 to 50000, more preferably 4000 to 40000, and particularly preferably 4000 to 30000. When the number average molecular weight is less than 3000, the heat resistance and mechanical properties of the resulting cured insulating film tend to be reduced.

  When a diol having a carboxyl group is used as the component (c ′) which is a raw material component of the polyurethane imide, the acid value of the polyurethane imide is preferably 5 to 120 mgKOH / g, more preferably 10 to 50 mg KOH / g. When the acid value is less than 5 mgKOH / g, the reactivity with the epoxy group-containing compound having a tricyclodecane structure is lowered, and the heat resistance of the protective film of the wiring board obtained by curing the thermosetting composition described later is low. May be. On the other hand, if it exceeds 120 mgKOH / g, the protective film may be too hard and brittle.

  This polyurethane preferably has a number average molecular weight of 3000 to 50000 and an acid value of 5 to 120 mgKOH / g, more preferably a number average molecular weight of 4000 to 30000 and an acid value of 10 to 10. 50 mg KOH / g.

When the stability of the synthesized polyimide polyurethane is regarded as important among the polyurethane polyimides that have a functional group capable of reacting with an epoxy group and have the structural unit represented by the formula (1) and further have an imide bond Than the polyurethane polyimide having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) and further having an imide bond, as described in JP-A-2003-198105. Polyurethane polyimide having a functional group capable of reacting with an epoxy group described in JP-A-2006-307183, a structural unit represented by the formula (1), and further having an imide bond is preferable. Particularly preferred is a polyurethane polyimide obtained by reacting raw materials essentially comprising the following (a), (b), (c) and (d).
Component (a) diisocyanate,
Component (b) (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms,
Component (c) a diol having a carboxyl group,
Component (d) A bifunctional hydroxyl-terminated imide represented by the formula (3).

  Next, a polyurethane having a certain branched structure in the molecule as long as it dissolves in a solvent, a functional group capable of reacting with an epoxy group, and a structural unit represented by the formula (1) will be described.

A polyurethane having a certain branched structure in the molecule within a range that dissolves in a solvent, a functional group capable of reacting with an epoxy group, and a structural unit represented by the formula (1) includes the following component (a) and component: It can be obtained by reacting raw material components essentially comprising (b), component (c) and component (e).
Component (a) diisocyanate,
Component (b) (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms,
Component (c) a diol having a carboxyl group,
Component (e) A compound having 3 or more hydroxyl groups in one molecule.

  The diisocyanate of component (a) may be any 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-cyclohexane diisocyanate, isophorone diisocyanate, methylene bis (4-cyclohexyl isocyanate), 1,3-bis (isocyanatomethyl) cyclohexane, 1,4-bis (isocyanatomethyl) cyclohexane, 2,4-tolylene diisocyanate 2,6-tolylene diisocyanate, diphenylmethane-4,4'-diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, lysine diisocyanate, hexamethylene diisocyanate, 2,4,4-trimethylhexamethylene Gii Cyanate, 2,2,4-trimethyl hexane diisocyanate and norbornene diisocyanate can be preferably exemplified.

  As the (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms as component (b), the number average molecular weight is preferably 400 to 10,000, more preferably 450 to 5000, most preferably 500. ~ 3000. When the number average molecular weight is less than 400, 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 (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms is specifically UH-CARB, UN-CARB, UD-CARB, UC-CARB, Daicel manufactured by Ube Industries, Ltd. Product names PLACEL, CD-205, 205PL, 205HL, 210, 210PL, 210HL, 220, 220PL, 220HL, Kuraray Co., Ltd., trade names Kuraray Polyol C-590, C-1065N, C-1015N C-2015N and the like can be preferably exemplified. These polycarbonate polyols are used alone or in combination of two or more.

As described above, when the (poly) carbonate polyol is produced, the polyol component as a raw material may be left and contained, but in this specification, the remaining polyol component is “(poly) It is defined as not included in “carbonate polyol”.
For example, when a (poly) carbonate polyol is produced by transesterification using trimethylolpropane, 1,9-nonanediol and diethyl carbonate as raw materials in the presence of a catalyst, When 5% by mass of 9-nonanediol remained in the product (poly) carbonate polyol, the remaining trimethylolpropane and 1,9-nonanediol were “(poly) When the polyol is a compound having 3 or more hydroxyl groups in one molecule (in this case, trimethylolpropane) without being included in the “carbonate carbonate polyol”, it means that the polyol belongs to the component (e). And a polyol having two hydroxyl groups in one molecule (in this case, 1, - in the case of nonanediol) is meant to be included in the components described below (y).

  Examples of the diol having a carboxyl group as the component (c) include 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, N, N-bis (hydroxyethyl) glycine, N, N-bis ( Hydroxyethyl) glycine and the like can be mentioned. Among these, 2,2-dimethylolpropionic acid and 2,2-dimethylolbutanoic acid are particularly preferable from the viewpoint of solubility in a solvent. These diols having a carboxyl group may be used alone or in combination of two or more.

  Examples of the compound having 3 or more hydroxyl groups in one molecule of component (e) include glycerin, trimethylolethane, trimethylolpropane, tris (2-hydroxyethyl) isocyanurate, pentaerythritol, dipentaerythritol, sorbitol, and the like. Can be mentioned. Of these, trimethylolethane, trimethylolpropane, and tris (2-hydroxyethyl) isocyanurate are particularly preferable in view of ease of synthesis.

  As described above, when the (poly) carbonate polyol is produced, the polyol component as a raw material may be left and contained, but the remaining polyol component has a compound having three or more hydroxyl groups in one molecule. Is included in the component (e).

If necessary, in addition to component (b), component (c) and component (e), a diol component not included in any of component (b), component (c) and component (e) (below) , Described as component (y)).
Examples of the component (y) include 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, and 1,5-pentanediol. 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,8-octanediol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,9-nonanediol, 2 -Methyl-1,8-octanediol, 1,10-decamethylene glycol, 1,2-tetradecanediol, 2,4-diethyl-1,5-pentanediol, 2-butyl-2-ethylpropanediol, 1, Examples include 3-cyclohexanedimethanol, 1,3-xylylene glycol, and 1,4-xylylene glycol.

  In addition, as described above, when the (poly) carbonate polyol is produced, the polyol component as a raw material may be left and contained, but the remaining polyol component has a compound having two hydroxyl groups in one molecule ( That is, when it is a diol), it means that it is contained in the component (y) described later.

  As the polyurethane having a functional group capable of reacting with an epoxy group which is a component of the thermosetting composition of the present invention and having a structural unit represented by the formula (1), the above component (a), component (b), When using the polyurethane obtained by reacting the raw material component which makes component (c) and component (e) essential, as a manufacturing method of this polyurethane, it can manufacture with the following method, for example.

  A raw material component which essentially comprises component (a), component (b), component (c) and component (e) using a solvent in the presence or absence of a known urethanization catalyst such as dibutyltin dilaurate (If necessary, the component (y)) can be reacted. It is preferable to carry out this reaction without a catalyst because the physical property value of the protective film for the wiring board of the present invention (II) to be described later is improved.

  Although there is no restriction | limiting in particular about the order which prepares these raw materials, Usually, a component (b), a component (c), a component (e), and a component (y) as needed are prepared first, and it melt | dissolves in a solvent. Then, component (a) is added dropwise at 20 to 140 ° C., more preferably 60 to 120 ° C., and then reacted at 50 to 160 ° C., more preferably 60 to 150 ° C.

  The starting molar ratio of the raw materials is the molecular weight and acid value of the polyurethane obtained by reacting the desired raw material components essentially comprising component (a), component (b), component (c) and component (e). Adjust accordingly. The molecular weight of the polyurethane can also be adjusted by using a monohydroxyl compound. That is, when the target number average molecular weight is reached (or when the target number average molecular weight is approached), a monohydroxyl compound is added for the purpose of blocking the terminal isocyanate group and further suppressing the increase in the number average molecular weight. .

  When using a monohydroxyl compound, the number of isocyanate groups in the polyisocyanate compound may be less than or equal to the number of total hydroxyl groups in component (b), component (c), component (e) and component (y). Or even if it increases, there is no problem.

  Further, when an excess of monohydroxyl compound is used, an unreacted monohydroxyl compound remains. In this case, the excess monohydroxyl compound may be used as a part of the solvent as it is. Alternatively, it may be removed by distillation or the like.

  The introduction of the monohydroxyl compound into the polyurethane obtained by reacting the raw material components essentially comprising component (a), component (b), component (c) and component (e) increases the molecular weight of this polyurethane. In order to suppress (that is, stop the reaction), and in order to introduce the monohydroxyl compound into this polyurethane, the monohydroxyl compound is dropped into the solution at 20 to 150 ° C., more preferably at 70 to 140 ° C., Thereafter, the reaction is completed by maintaining at the same temperature.

  Moreover, it is preferable that the usage-amount of a component (e) is 0.1-5.0 mass% of all the raw material components, More preferably, it is 0.2-2.0 mass%, Most preferably, 0.3 to 1.5% by mass. If it is less than 0.1% by mass, the added effect may not be exhibited, which is not preferable. Moreover, when more than 5.0 mass%, molecular weight adjustment at the time of a synthesis | combination may become difficult, and it is unpreferable.

  As described above, the number average molecular weight of the polyurethane obtained by reacting the raw material components essentially comprising the component (a), the component (b), the component (c) and the component (e) is 1000 to 100,000. Is preferable, More preferably, it is 3000-50000, Most preferably, it is 5000-30000.

The “number average molecular weight” described in the present specification is a number average molecular weight in terms of polystyrene measured by gel permeation chromatography (hereinafter referred to as GPC). If the number average molecular weight is less than 1,000, the elongation, flexibility, and strength of the cured film may be impaired. Becomes higher, and there may be restrictions in terms of use.
In this specification, unless otherwise specified, the GPC measurement conditions are as follows.
Device name: HPLC unit HSS-2000 manufactured by JASCO Corporation
Column: Shodex column LF-804 (3 in series)
Mobile phase: Tetrahydrofuran Flow rate: 1.0 mL / min
Detector: JASCO Corporation RI-2031Plus
Temperature: 40.0 ° C
Sample amount: 100 μl of sample loop Sample concentration: prepared at around 0.1% by mass.

  The acid value of this polyurethane is preferably 5 to 120 mgKOH / g, more preferably 10 to 50 mgKOH / g. When the acid value is less than 5 mgKOH / g, the reactivity with the epoxy group-containing compound having a tricyclodecane structure is lowered, and the heat resistance of the protective film of the wiring board obtained by curing the protective film thermosetting composition is low. May be. On the other hand, if it exceeds 120 mgKOH / g, the protective film may be too hard and brittle.

This polyurethane is preferably a polyurethane having a number average molecular weight of 1,000 to 100,000 and an acid value of 5 to 120 mgKOH / g and having a functional group capable of curing reaction and a carbonate bond, and more preferably a number average molecular weight of 3000. The acid value is 10-50 mg KOH / g.
In addition, in this specification, the acid value of polyurethane is a value of an acid value measured by a potentiometric titration method of JIS K0070.

  As a solvent that can be suitably used in the reaction for producing the polyurethane, paragraph [0191] can be used as a solvent that can be used in the synthesis of the polyurethane polyimide having the structural units represented by the formulas (4) to (6). ] To [0197] can be used.

  Next, a polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) and further containing an organic residue derived from dimer diol will be described.

（式中、Ｒ^１０およびＲ^１１は何れもアルキル基であり、ｐおよびｑは０以上の整数であり、かつＲ^１０およびＲ^１１に含まれる各炭素数ならびにｐおよびｑの合計は３０である。）

（式中、Ｒ^１２およびＲ^１３は何れもアルキル基であり、ｒおよびｓは０以上の整数であり、かつＲ^１２およびＲ^１３に含まれる各炭素数ならびにｒおよびｓの合計は３４である。）In the present specification, the “dimer diol” means that a dimer acid and / or a lower alcohol ester thereof is reduced in the presence of a catalyst and a diol having a carbon number of 36 having a carboxylic acid portion of the dimer acid as an alcohol as a main component. It is what. Here, the main component means that it is present in an amount of 50% by mass or more. In addition to a diol having 36 carbon atoms, there may be a diol having 22 to 44 carbon atoms and not 36 carbon atoms. As the dimer diol in the present specification, a hydrogenated dimer diol obtained by hydrogenating a carbon-carbon double bond derived from dimer acid is particularly preferable. Examples of commercially available dimer diols include PRIPOL (registered trademark) 2033 (manufactured by Croda) and Sovermol (registered trademark) 908 (manufactured by Cognis). PRIPOL (registered trademark) 2033 is mainly composed of a mixture of compounds represented by the following formulas (48) and (49). The “dimer acid” is an acid obtained by an intermolecular dimerization reaction of an unsaturated fatty acid, and an unsaturated fatty acid having 11 to 22 carbon atoms forms a dimer having 36 carbon atoms. A dibasic acid obtained by dimerization by blending is a main component. Examples of commercially available products include PRIPOL (registered trademark) 1006, 1009, 1015, 1025 and the like (manufactured by Croda), and EMPOL (registered trademark) 1062 (Cognis).

(Wherein R ¹⁰ and R ¹¹ are both alkyl groups, p and q are integers of 0 or more, and the number of carbon atoms contained in R ¹⁰ and R ¹¹ and the sum of p and q are 30) .)

(Wherein R ¹² and R ¹³ are all alkyl groups, r and s are integers of 0 or more, and the total number of carbon atoms contained in R ¹² and R ¹³ and r and s is 34. .)

The “organic residue derived from dimer diol” in the present invention means a structure excluding hydrogen of at least one alcoholic hydroxyl group of the dimer diol.
The “organic residue derived from a diol having 3 to 18 carbon atoms” in the present invention means a structure excluding hydrogen of at least one alcoholic hydroxyl group of the diol having 3 to 18 carbon atoms.

A polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) and further containing an organic residue derived from dimer diol includes, for example, the following component (a), It can synthesize | combine by making the raw material component (component (z) as needed) which makes a component (b), a component (c), and a component (l) essential.
Component (a) diisocyanate,
Component (b) (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms,
Component (c) a diol having a carboxyl group,
Component (l) Dimer diol Component (z) Polyol other than polyol selected from the group consisting of component (b), component (c) and component (l)

  The diisocyanate of component (a) may be any 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-cyclohexane diisocyanate, isophorone diisocyanate, methylene bis (4-cyclohexyl isocyanate), 1,3-bis (isocyanatomethyl) cyclohexane, 1,4-bis (isocyanatomethyl) cyclohexane, 2,4-tolylene diisocyanate 2,6-tolylene diisocyanate, diphenylmethane-4,4'-diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, lysine diisocyanate, hexamethylene diisocyanate, 2,4,4-trimethylhexamethylene Gii Cyanate, 2,2,4-trimethyl hexane diisocyanate and norbornene diisocyanate can be preferably exemplified.

  As the (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms as component (b), the number average molecular weight is preferably 400 to 10,000, more preferably 450 to 5000, most preferably 500. ~ 3000. When the number average molecular weight is less than 400, 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 (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms is specifically UH-CARB, UN-CARB, UD-CARB, UC-CARB, Daicel manufactured by Ube Industries, Ltd. Product names PLACEL, CD-205, 205PL, 205HL, 210, 210PL, 210HL, 220, 220PL, 220HL, Kuraray Co., Ltd., trade names Kuraray Polyol C-590, C-1065N, C-1015N C-2015N and the like can be preferably exemplified. These polycarbonate polyols are used alone or in combination of two or more.

As described above, when the (poly) carbonate polyol is produced, the polyol component as a raw material may be left and contained, but in this specification, the remaining polyol component is “(poly) It is defined as not included in “carbonate polyol”.
For example, when (poly) carbonate polyol is produced by transesterification using 1,9-nonanediol and diethyl carbonate as raw materials in the presence of a catalyst, the raw material 1,9-nonanediol is a product. When 5% by mass remains in a certain (poly) carbonate polyol, the remaining 1,9-nonanediol is not included in the “(poly) carbonate polyol”, but the component (z ).

  Examples of the diol having a carboxyl group as the component (c) include 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, N, N-bis (hydroxyethyl) glycine, N, N-bis ( Hydroxyethyl) glycine and the like can be mentioned. Among these, 2,2-dimethylolpropionic acid and 2,2-dimethylolbutanoic acid are particularly preferable from the viewpoint of solubility in a solvent. These polyols having a carboxyl group may be used alone or in combination of two or more.

  As described above, the dimer diol of component (l) is mainly a diol having 36 carbon atoms in which dimer acid and / or its lower alcohol ester is reduced in the presence of a catalyst, and the carboxylic acid portion of dimer acid is alcohol. Ingredients. Here, the main component means that it is present in an amount of 50% by mass or more. In addition to a diol having 36 carbon atoms, there may be a diol having 22 to 44 carbon atoms and not 36 carbon atoms. As the dimer diol in the present specification, a hydrogenated dimer diol obtained by hydrogenating a carbon-carbon double bond derived from dimer acid is particularly preferable. Examples of commercially available dimer diols include PRIPOL 2033 (manufactured by Croda) and Sovermol 908 (manufactured by Cognis).

Further, in addition to the component (a), the component (b), the component (c) and the component (l) as necessary, the component (a), the component (b), the component (c) and the component (l) A diol component (component (z)) not included in any of them can be used in combination.
Examples of the component (z) include 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, and 1,5-pentanediol. 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,8-octanediol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,9-nonanediol, 2 -Methyl-1,8-octanediol, 1,10-decamethylene glycol, 1,2-tetradecanediol, 2,4-diethyl-1,5-pentanediol, 2-butyl-2-ethylpropanediol, 1, Examples include 3-cyclohexanedimethanol, 1,3-xylylene glycol, and 1,4-xylylene glycol.

  In addition, when the (poly) carbonate polyol is produced, the polyol component as a raw material may remain and be included, but the remaining polyol component is not included in the component (b) but included in the component (z). Means that

  A polyurethane having a functional group capable of reacting with an epoxy group which is a component of the thermosetting composition of the present invention and having a structural unit represented by the formula (1) has a functional group capable of reacting with an epoxy group and When a polyurethane having a structural unit represented by the formula (1) and further containing an organic residue derived from dimer diol is used, the polyurethane may be produced, for example, by the following method. Can do.

  A raw material component which essentially comprises component (a), component (b), component (c) and component (l) using a solvent in the presence or absence of a known urethanization catalyst such as dibutyltin dilaurate It can synthesize | combine by making (component (z)) react as needed. It is preferable to carry out this reaction without a catalyst because the physical property value of the protective film for the wiring board of the present invention (II) to be described later is improved.

  Although there is no restriction | limiting in particular about the order which prepares these raw materials, Usually, a component (b), a component (c), a component (l), and a component (z) are prepared first, and it melt | dissolves in a solvent as needed. Then, component (a) is added dropwise at 20 to 140 ° C., more preferably 60 to 120 ° C., and then reacted at 50 to 160 ° C., more preferably 60 to 150 ° C.

  The starting molar ratio of the raw materials is the molecular weight and acid value of the polyurethane obtained by reacting the desired raw material components essentially comprising component (a), component (b), component (c) and component (l). Adjust accordingly. The molecular weight of the polyurethane can also be adjusted by using a monohydroxyl compound. That is, when the target number average molecular weight is reached (or when the target number average molecular weight is approached), a monohydroxyl compound is added for the purpose of blocking the terminal isocyanate group and further suppressing the increase in the number average molecular weight. .

  When using a monohydroxyl compound, the same is true even if the number of isocyanate groups in component (a) is less than the total number of hydroxyl groups in component (b), component (c), component (l) and component (z). But it doesn't matter if you increase it or not.

  Further, when an excess of monohydroxyl compound is used, an unreacted monohydroxyl compound remains. In this case, the excess monohydroxyl compound may be used as a part of the solvent as it is. Alternatively, it may be removed by distillation or the like.

  The introduction of the monohydroxyl compound into the polyurethane obtained by reacting the raw material components essential to the component (a), the component (b), the component (c) and the component (l) increases the molecular weight of the polyurethane. In order to suppress (that is, stop the reaction), and in order to introduce the monohydroxyl compound into this polyurethane, the monohydroxyl compound is dropped into the solution at 20 to 150 ° C., more preferably at 70 to 140 ° C., Thereafter, the reaction is completed by maintaining at the same temperature.

  Moreover, it is preferable that the usage-amount of a component (l) is 5-50 mass% with respect to the total amount of a component (b), a component (c), a component (l), and a component (z), More preferably 10 to 45 mass%, and most preferably 15 to 40 mass%. When the amount is less than 5% by mass, the added effect may not be exhibited, which is not preferable. Moreover, when more than 50 mass%, the adhesiveness to the polyimide substrate of the protective film mentioned later may fall, and it is unpreferable.

As described above, the number average molecular weight of the polyurethane obtained by reacting the raw material components essentially comprising the component (a), the component (b), the component (c) and the component (l) is 1000 to 100,000. Is preferable, More preferably, it is 3000-50000, Most preferably, it is 5000-30000.
If the number average molecular weight is less than 1000, the elongation, flexibility, and strength of the cured film may be impaired. If the number average molecular weight exceeds 100000, the solubility in a solvent becomes low and the viscosity increases even if dissolved. There may be restrictions on usage.

  The acid value of this polyurethane is preferably 5 to 120 mgKOH / g, more preferably 10 to 50 mgKOH / g. When the acid value is less than 5 mgKOH / g, the reactivity with the epoxy group-containing compound having a tricyclodecane structure is lowered, and the heat resistance of the protective film of the wiring board obtained by curing the protective film thermosetting composition is low. May be. On the other hand, if it exceeds 120 mgKOH / g, the protective film may be too hard and brittle.

  This polyurethane is preferably a polyurethane having a number average molecular weight of 1,000 to 100,000 and an acid value of 5 to 120 mgKOH / g and having a functional group capable of curing reaction and a carbonate bond, and more preferably a number average molecular weight of 3000. The acid value is 10-50 mg KOH / g.

  As a solvent that can be suitably used in the reaction for producing the polyurethane, paragraph [0191] can be used as a solvent that can be used in the synthesis of the polyurethane polyimide having the structural units represented by the formulas (4) to (6). ] To [0197] can be used.

  The solvent, which is an essential component of the thermosetting composition of the present invention (I), was used for the synthesis of a polyurethane having a functional group capable of reacting with the aforementioned epoxy group and having a structural unit represented by the formula (1). It is economically preferable to use the solvent as it is as the solvent of the thermosetting composition of the present invention (I). Moreover, you may add a solvent further in the meaning which adjusts a viscosity. The concentration of the solvent in the thermosetting composition of the present invention (I) is preferably 10 to 90% by mass, more preferably 20 to 70% by mass.

The thermosetting composition of the present invention (I) can further preferably contain a curing accelerator. The curing accelerator is not particularly limited as long as it is a compound that promotes the reaction between an epoxy group and a carboxyl group. For example, melamine, acetoguanamine, benzoguanamine, 2,4-diamino-6-methacryloyloxyethyl-s -Triazines such as triazine, 2,4-methacryloyloxyethyl-s-triazine, 2,4-diamino-6-vinyl-s-triazine, 2,4-diamino-6-vinyl-s-triazine and isocyanuric acid adducts Compounds, imidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1-benzyl-2-methylimidazole, 2-phenyl-4- Methylimidazole, 1-cyanoethyl-2 Methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-aminoethyl-2-ethyl-4-methylimidazole, 1-aminoethyl-2-methylimidazole, 1- (cyanoethylaminoethyl) -2-methyl Imidazole, N- [2- (2-Methyl-1-imidazolyl) ethyl] urea, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-methylimidazolium trimellitate, 1-cyanoethyl-2-phenyl Imidazolium trimellitate, 1-cyanoethyl-2-ethyl-4-methylimidazolium trimellitate, 1-cyanoethyl-2-undecylimidazolium trimellitate, 2,4-diamino-6- [2'-methyl Imidazolyl- (1 ′)]-ethyl-s-triazine 2,4-diamino-6- [2'-undecylimidazolyl- (1 ')]-ethyl-s-triazine, 2,4-diamino-6- [2'-ethyl-4'-methylimidazolyl- (1 ′)]-Ethyl-s-triazine, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, N, N′-bis (2-methyl-1-imidazolylethyl) urea, N, N′-bis ( 2-methyl-1-imidazolylethyl) adipamide, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl-4.5-dihydroxymethylimidazole, 2-methylimidazole isocyanuric acid adduct, 2-phenyl Imidazole-isocyanuric acid adduct, 2,4-diamino-6- [2'-methylimidazolyl- (1 ')]-ethyl-s-tria Gin isocyanuric acid adduct, 2-methyl-4-formylimidazole, 2-ethyl-4-methyl-5-formylimidazole, 2-phenyl-4-methylformylimidazole, 1-benzyl-2-phenylimidazole, 1,2-dimethylimidazole, 1- (2-hydroxyethyl) imidazole, vinylimidazole, 1-methylimidazole, 1-allylimidazole, 2-ethylimidazole, 2-butylimidazole, 2-butyl-5-hydroxymethylimidazole, Imidazoles such as 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole, 1-benzyl-2-phenylimidazole hydrobromide, 1-dodecyl-2-methyl-3-benzylimidazolium chloride Compound, 1,5-diazabicyclo 4.3.0) Nonamen-5 and salts thereof, cycloamidine compounds such as diazabicycloalkenes such as 1,8-diazabicyclo (5.4.0) undecene-7 and salts thereof, and derivatives thereof, triethylenediamine, benzyl Tertiary amino group-containing compounds such as dimethylamine, triethanolamine, dimethylaminoethanol, tris (dimethylaminomethyl) phenol, triphenylphosphine, diphenyl (p-tolyl) phosphine, tris (alkylphenyl) phosphine, tris (alkoxyphenyl) ) Phosphine, tris (alkylalkoxyphenyl) phosphine, tris (dialkylphenyl) phosphine, tris (trialkylphenyl) phosphine, tris (tetraalkylphenyl) phosphine, tris (dialkoxypheny) ) Phosphine, tris (tri-alkoxyphenyl) phosphine, tris (tetra-alkoxyphenyl) phosphine, trialkyl phosphine, dialkyl aryl phosphines, organic phosphine compounds such as an alkyl diaryl phosphines, can be given Jishianjiajido like.
These curing accelerators may be used alone or in combination of two or more.

  Among these curing accelerators, in view of achieving both a curing accelerating action and electrical insulation performance, preferred are melamine, imidazole compounds, cycloamidine compounds and derivatives thereof, phosphine compounds, and amine compounds. More preferred are melamine, 1,5-diazabicyclo (4.3.0) nonene-5 and salts thereof, and 1,8-diazabicyclo (5.4.0) undecene-7 and salts thereof.

  There is no restriction | limiting in particular if the compounding quantity of these hardening accelerators can achieve the hardening acceleration effect. However, from the viewpoints of curability of the thermosetting composition of the present invention (I) and electrical insulating properties and water resistance of the protective film obtained by curing the thermosetting composition of the present invention (I), the present invention Of the epoxy group-containing compound having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) and a tricyclodecane structure contained in the thermosetting composition of (I) It is preferable to mix | blend in the range of 0.05-5 mass parts with respect to 100 mass parts of total amounts, More preferably, it is 0.1-3.0 mass parts. When the blending amount is less than 0.05 parts by mass, it is difficult to cure in a short time, and when it exceeds 5 parts by mass, the electrical insulation characteristics and water resistance of the cured product obtained by curing the composition are deteriorated. There is.

In the thermosetting composition of the present invention (I), inorganic fine particles and / or organic fine particles can be blended and preferably blended for the purpose of adjusting fluidity.
In the present specification, “inorganic fine particles and / or organic fine particles” means not only inorganic fine particles and organic fine particles, but also a powdery inorganic compound physically coated with an organic compound or chemically surfaced with an organic compound. It is defined to include organic / inorganic composite-based fine particles that have been treated.

  Inorganic fine particles and / or organic fine particles that may be used for the purpose of blending in the thermosetting composition of the present invention (I) contain an epoxy group having a tricyclodecane structure, which is an essential component of the present invention (I). There is no particular limitation as long as the paste is dispersed in a composition containing a compound, a polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1), and a solvent.

Examples of the inorganic fine particles include silica (SiO ₂ ), alumina (Al ₂ O ₃ ), titania (TiO ₂ ), tantalum oxide (Ta ₂ O ₅ ), zirconia (ZrO ₂ ), and silicon nitride (Si ₃ N ₄ ). , Barium titanate (BaO · TiO ₂ ), barium carbonate (BaCO ₃ ), lead titanate (PbO · TiO ₂ ), lead zirconate titanate (PZT), lead lanthanum zirconate titanate (PLZT), gallium oxide ( Ga ₂ O _3), spinel _{(MgO · Al 2 O 3)} , mullite _{(3Al 2 O 3 · 2SiO 2} ), cordierite _{(2MgO · 2Al 2 O 3 ·} 5SiO 2), talc (3MgO · 4SiO ₂ · H ₂ O), aluminum titanate _{(TiO 2 -Al 2 O 3)} , yttria-containing zirconia _{(Y 2} O 3 -ZrO ₂₎ Barium silicate (BaO · 8SiO _2), boron nitride (BN), calcium carbonate (CaCO _3), calcium sulfate (CaSO _4), zinc oxide (ZnO), magnesium titanate (MgO · _TiO 2), barium sulfate (BaSO ₄ ), Organic bentonite, carbon (C) and the like, and these can be used alone or in combination of two or more.

  The organic fine particles are preferably heat-resistant resin fine particles having an amide bond, an imide bond, an ester bond or an ether bond. The resin is preferably a polyimide resin or a precursor thereof, a polyamideimide resin or a precursor thereof, or a polyamide resin from the viewpoint of heat resistance and mechanical properties.

  The average particle diameter of these inorganic fine particles and / or organic fine particles is preferably 0.01 to 10 μm, more preferably 0.1 to 5 μm.

  The blending amount of the inorganic fine particles and / or the organic fine particles is 1-150 parts by mass, preferably 1 with respect to 100 parts by mass of the total amount of the carboxyl group-containing polyurethane, solvent and curing agent contained in the curable resin composition. It is -120 mass parts, More preferably, it is 1-60 mass parts.

The thermosetting composition for a protective film of a wiring board according to the present invention (I) is, for example, a heat for a protective film of a wiring board for Chip On Film (hereinafter referred to as COF) patterned using a screen printing method. It can be used as a curable composition.
Note that “COF” described in this specification means a mounting method in which a bare chip is mounted on a flexible wiring board and connected.

When the thermosetting composition of the present invention (I) is used as a thermosetting composition for a protective film of a wiring board for COF patterned using a screen printing method, generation of bubbles during printing An antifoaming agent can be used and preferably used for the purpose of eliminating or suppressing the odor.
The antifoaming agent is not particularly limited as long as it literally has an action of eliminating or suppressing bubbles generated when the thermosetting composition of the present invention (I) is printed.
Specific examples of the antifoaming agent used in the thermosetting composition of the present invention (I) include, for example, BYK-077 (manufactured by Big Chemie Japan), SN deformer 470 (manufactured by San Nopco), TSA750S (momentive Performance Materials Co., Ltd.), silicone-based antifoaming agents such as silicone oil SH-203 (Toray Dow Corning Co., Ltd.), Dappo SN-348 (manufactured by San Nopco), Dappo SN-354 (manufactured by San Nopco), Acrylic polymer antifoaming agents such as Dappo SN-368 (manufactured by San Nopco), Disparon 230HF (manufactured by Enomoto Kasei Co., Ltd.), Surfinol DF-110D (manufactured by Nissin Chemical Industry Co., Ltd.), Surfynol DF-37 (Nissan) Acetylene diol type antifoaming agent such as Shin-Chemical Industry Co., Ltd., and fluorine-containing FA-630 etc. Mention may be made of a silicone-based anti-foaming agents, and the like.

  Furthermore, the thermosetting composition of the present invention (I) includes surfactants such as a leveling agent, phthalocyanine blue, phthalocyanine green, iodin green, disazo yellow, kustal violet, carbon as necessary. Known colorants such as black and naphthalene black can be added.

  In addition, when it is necessary to suppress deterioration of the acid value of the resin and discoloration during heating, it is possible to add an antioxidant such as a phenolic antioxidant, a phosphite antioxidant, or a thioether antioxidant. And preferably added.

Examples of the phenolic antioxidant include compounds represented by the following formulas (50) to (60).

Examples of the phosphite antioxidant include compounds represented by the following formulas (61) to (71).

Examples of the thioether-based antioxidant include compounds represented by the following formulas (72) to (77).

  Moreover, a flame retardant and a lubricant can also be added as needed.

  The thermosetting composition of the present invention (I) can be obtained by uniformly kneading and mixing part or all of the blending components with a roll mill, a bead mill or the like. When a part of the blending components is mixed, the remaining components can be mixed when actually used.

  Furthermore, when the thermosetting composition of the present invention (I) is used as a thermosetting composition for a protective film of a wiring board for COF patterned by a screen printing method, the heat of the present invention (I) In order to improve the printability of the curable composition, it is desirable to have a certain range of thixotropy index.

  The “thixotropy index” described in the present specification is a cone / plate viscometer (Brookfield model: DV-II + Pro spindle model number: CPE-52), measured at 1 rpm at 25 ° C. It is defined as the ratio of the viscosity at the time of 10 to the viscosity at a rotation speed of 10 rpm at 25 ° C.

  When the thermosetting composition of the present invention (I) is used as a thermosetting composition for a protective film patterned by a screen printing method, the printability of the thermosetting composition of the present invention (I) is good. Therefore, the thixotropy index at 25 ° C. of the composition is preferably in the range of 1.1 to 3.0, more preferably in the range of 1.1 to 2.5. When using the thermosetting composition of this invention (I) as a soldering resist ink composition, when the thixotropy index in 25 degreeC of a thermosetting composition became less than 1.1, the thermosetting composition was printed. Later, the composition may flow, so that the film thickness may not be constant or the printed pattern may not be maintained. Moreover, if the thixotropy index at 25 ° C. of the thermosetting composition is larger than 3.0, the defoaming property of the coating film of the printed composition may be deteriorated.

Next, the protective film of the wiring board of the present invention (II) will be described.
The present invention (II) is a protective film for a wiring board obtained by curing the thermosetting composition for a protective film for a wiring board according to the present invention (I).

The protective film for the wiring board of the present invention (II) removes part or all of the solvent in the thermosetting composition for the protective film of the wiring board of the present invention (I), and then proceeds with the curing reaction by heating. In general, a cured product is obtained. For example, when obtaining the protective film of the wiring board of the present invention (II), the protective film can be obtained through the following first to third steps.
1st process The process of printing the thermosetting composition of this invention (I), and obtaining a coating film.
2nd process The process of obtaining the coating film from which the solvent was evaporated in the atmosphere of 20 to 100 degreeC, and the solvent of one part or all quantity was removed from the coating film obtained at the 1st process.
3rd process The process of heat-curing the coating film obtained at the 2nd process in the atmosphere of 100 to 250 degreeC, and obtaining the thermosetting coating film (namely, cured coating film).

  The first step is a step of printing the thermosetting composition of the present invention (I) to obtain a coating film, but there is no particular limitation on the printing method of the thermosetting composition of the present invention (I), for example, A coating film can be obtained by coating by a screen printing method, a roll coater method, a spray method, a curtain coater method or the like, and most preferably a screen printing method.

  The second step is a step of obtaining a coating film from which part or all of the solvent has been removed by evaporating the solvent from the coating film obtained in the first step in an atmosphere of 20 ° C. to 100 ° C. The time for removing the solvent is preferably 4 hours or less, more preferably 2 hours or less.

  In addition, the third step is a step in which the coating film obtained in the second step is heat-cured in an atmosphere of 100 ° C. to 250 ° C. to obtain a heat-cured coating film (that is, a cured coating film). . The time for thermosetting is preferably in the range of 20 minutes to 4 hours, more preferably in the range of 30 minutes to 2 hours.

  Finally, a method for manufacturing the flexible wiring board of the present invention (III) and the flexible wiring board of the present invention (IV) covered with a protective film will be described.

  In the present invention (III), a part or all of the surface of the flexible wiring board in which the wiring is formed on the flexible substrate is covered with the protective film for the wiring board described in the present invention (II). This is a flexible wiring board covered with a protective film.

  In the present invention (IV), a printed film is formed on the pattern by printing the thermosetting composition for the protective film of the wiring board of the present invention (I) on the wiring pattern portion subjected to tin plating of the flexible wiring board. Then, the printed film is heated and cured at 80 to 130 ° C. to form a protective film, which is a method for producing a flexible wiring board covered with a protective film.

  The thermosetting composition of the present invention (I) can be used, for example, as a protective film for a wiring board for COF by covering the entire surface or a part of the wiring of the flexible wiring board for COF.

Below, the specific process of the manufacturing method of this invention (IV) is described. For example, the protective film of a flexible wiring board can be formed through the following steps A to C.
Process A
The process of screen-printing the thermosetting composition of this invention (I) on the wiring pattern part by which the tin plating process of the flexible wiring board was carried out previously, and obtaining a coating film.
Process B
A step of evaporating the solvent from the coating film obtained in step A in an atmosphere of 20 to 100 ° C. to obtain a coating film from which a part or all of the solvent has been removed.
Process C
The process of obtaining the protective film of the flexible wiring board by thermosetting the coating film obtained by the process B in 80-130 degreeC atmosphere.

  The temperature for evaporating the solvent in Step B is 20 to 100 ° C., preferably 60 to 100 ° C., more preferably, considering the evaporation rate of the solvent and the quick transition to the next step (Step C). , 70-90 ° C. Although there is no restriction | limiting in particular in the time to evaporate the solvent of process B, Preferably, it is 10 to 120 minutes, More preferably, it is 20 to 100 minutes. The operation of the step B is an operation performed as necessary. The operation of the step C may be performed immediately after the operation of the step A, and the curing reaction and the removal of the solvent may be performed together.

  The conditions for thermosetting performed in the step C are in the range of 80 to 130 ° C. from the viewpoint of preventing the diffusion of the plating layer and obtaining warpage and flexibility suitable as a protective film. Preferably it is 90-130 degreeC, and is 110-130 degreeC. Although the time of the thermosetting performed at the process C does not have a restriction | limiting in particular, Preferably it is 20 to 150 minutes, More preferably, it is 30 to 120 minutes.

  The present invention will be described more specifically with reference to the following examples. However, the present invention is not limited to the following examples.

<Measurement of acid value>
The polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1), which is an essential component of the present invention (I), has a carboxyl group as a functional group capable of reacting with an epoxy group. In some cases, the acid value was measured by the following method.
The solvent in the polyurethane solution having a carboxyl group was distilled off under reduced pressure under heating to obtain a polyurethane having a carboxyl group.
Using this polyurethane having a carboxyl group, the acid value was measured according to the potentiometric titration method of JIS K0070.
The apparatus used in the potentiometric titration method is described below.
Device name: Kyoto Denshi Kogyo Co., Ltd. Automatic potentiometric titrator AT-510
Electrode: Composite glass electrode C-173 manufactured by Kyoto Electronics Industry Co., Ltd.

<Measurement of hydroxyl value>
The hydroxyl value was measured according to the neutralization titration method of JIS K0070.

<Measurement of number average molecular weight of polyurethane>
It is a value in terms of polystyrene measured by GPC, and GPC measurement conditions are as follows.
Device name: HPLC unit HSS-2000 manufactured by JASCO Corporation
Column: Three Shodex columns LF-804 connected (in series)
Mobile phase: Tetrahydrofuran Flow rate: 1.0 mL / min
Detector: RI-2031Plus manufactured by JASCO Corporation
Temperature: 40.0 ° C
Sample volume: Sample loop 100 μl
Sample concentration: adjusted to around 0.1% by mass

<Measurement of viscosity of polyurethane solution>
The viscosity of the carboxyl group-containing polyurethane solution was measured by the following method.
Using about 0.8 g of a carboxyl group-containing polyurethane solution, a cone / plate viscometer (Brookfield model: DV-II + Pro spindle model number: CPE-52), temperature 25.0 ° C., rotation speed 5 rpm Under the conditions, the viscosity after 7 minutes from the start of measurement was measured.

<Measurement of thixotropy index>
The thixotropy index of the thermosetting composition was measured by the following method.
Using a thermosetting composition of about 0.6 g, a thixotropy index was determined using a cone / plate viscometer (Brookfield model: DV-II + Pro spindle model number: CPE-52) at a temperature of 25.0 ° C. The viscosity was measured after 7 minutes from the start of measurement under the condition of 10 rpm. Thereafter, the viscosity was measured after 7 minutes from the start of measurement under the conditions of a temperature of 25.0 ° C. and a rotation speed of 1 rpm.
The thixotropy index was calculated by the following method.
How to find the thixotropy index:
Thixotropic index = [viscosity at 1 rpm] ÷ [viscosity at 10 rpm]

<Synthesis of bifunctional hydroxyl-terminated imide>
(Reference Synthesis Example 1) Production of bifunctional hydroxyl-terminated imide (A) In a 500-mL glass separable flask equipped with a nitrogen introduction tube, a Dean Star crusher, and a cooling tube, 2, 3, 3 ', 4'- Charge 58.8 g (0.20 mol) of biphenyltetracarboxylic dianhydride, 17.0 g (0.10 mol) of isophoronediamine, 15.0 g (0.20 mol) of 3-aminopropanol, and 200 mL of dimethylacetamide under a nitrogen atmosphere. , And stirred at 100 ° C. for 1 hour. Subsequently, 50 mL of toluene was added and heated at 180 ° C. for 4 hours, and water generated by the imidization reaction was removed azeotropically with toluene. The reaction solution was poured into 2 L of water, and the resulting precipitate was collected by filtration, washed with water and dried under reduced pressure to obtain 78.8 g of powder. From the result of ¹ H-NMR of this compound, this compound is a bifunctional hydroxyl-terminated imide having m (average value) of 1 in the formula (3) (hereinafter referred to as bifunctional hydroxyl-terminated imide (A)). It was confirmed that.

(Reference Synthesis Example 2) Production of bifunctional hydroxyl-terminated imide (B) In a 500 mL glass separable flask equipped with a nitrogen introduction tube, a Dean-Star cleaver and a cooling tube, 2,3,3 ', 4'- In a nitrogen atmosphere, 58.8 g (0.20 mol) of biphenyltetracarboxylic dianhydride, 25.55 g (0.15 mol) of isophoronediamine, 7.51 g (0.1 mol) of 3-aminopropanol, and 200 mL of dimethylacetamide were charged. , And stirred at 100 ° C. for 1 hour. Subsequently, 50 mL of toluene was added and heated at 180 ° C. for 4 hours, and water generated by the imidization reaction was removed azeotropically with toluene. The reaction solution was poured into 2 L of water, and the resulting precipitate was collected by filtration, washed with water and dried under reduced pressure to obtain 72.0 g of powder. From the result of ¹ H-NMR of this compound, this compound is a bifunctional hydroxyl-terminated imide having an m (average value) of 3 in formula (3) (hereinafter referred to as bifunctional hydroxyl-terminated imide (B)). It was confirmed that.

<Synthesis of polyurethane polyimide>
(Execution synthesis example 1)
Synthesis of Polyurethane Polyimide (1) A glass flask having a capacity of 300 mL equipped with a nitrogen introduction tube was added to Kuraray polyol C-2015 ((poly) carbonate diol and raw material diol (ie 1,6-hexanediol and 3-methyl-1). , 5-pentanediol), molar ratio of raw material diol; 1,6-hexanediol: 3-methyl-1,5-pentanediol = 85: 15, hydroxyl value 56.1 mgKOH / g, 1,6- Pexanediol residual concentration of 1.5% by mass, 3-methyl-1,5-pentanediol residual concentration of 0.5% by mass) 50.00 g (25 mmol), 2,2-dimethylolpropionic acid 3.35 g ( 25 mmol), 4,4′-diphenylmethane diisocyanate 15.64 g (62.5 mmol), γ-butyro G of tons 69.76G, under a nitrogen atmosphere and stirred 3.5 hours at 60 ° C.. Next, 20.92 g (25 mmol) of the bifunctional hydroxyl-terminated imide (A) prepared in Reference Example 2 and 20.92 g of γ-butyrolactone were added and stirred at 80 ° C. for 10 hours. The number average molecular weight determined from GPC of this polyurethane polyimide (hereinafter referred to as polyurethane polyimide (1)) solution was 6800. 23.75 g of a mixed solvent of γ-butyrolactone: diethylene glycol diethyl ether = 27.7: 72.3 (mass ratio) was added to the polyurethane polyimide (1) solution to adjust the solid content concentration to 44 mass%. The viscosity of this solution was 40 Pa · s. Moreover, the acid value of the polyurethane polyimide (1) was 15.6 mg-KOH / g.

(Execution synthesis example 2)
Synthesis of Polyurethane Polyimide (2) In a 5 liter glass container equipped with a nitrogen introduction tube, a 1,6-hexane polycarbonate diol PLACCELCD-220 ((poly) carbonate diol and raw material diol (ie, 1,6- Hexanediol), hydroxyl value 56.1 mgKOH / g, 1,6-hexanediol residual concentration 3.0 mass%) 1000.0 g (0.50 mol) and 4,4′-diphenylmethane diisocyanate 250.27 g (1 0.003 mol) and 833.15 g of γ-butyrolactone were charged, and the temperature was raised to 140 ° C. and reacted for 5 hours. Further, to this reaction mixture, 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic dianhydride 358.29 g (1.00 mol), 4,4′-diphenylmethane diisocyanate 125.14 g (0.50 mol), And 58.497 g of γ-butyrolactone were added and reacted at 160 ° C. for 5 hours. The obtained polyurethane polyimide (hereinafter referred to as polyurethane polyimide (2)) is diluted with a mixed solvent of γ-butyrolactone: diethylene glycol diethyl ether = 67: 33 (mass ratio), and has a viscosity of 40 Pa · s and a solid content concentration of 40 mass. % Polyurethane polyimide (2) solution was obtained. The number average molecular weight of this polyurethane polyimide (2) obtained from GPC was 14,000.
The polyurethane polyimide (2) was measured for infrared absorption (IR) spectrum, and absorption of carboxylic acid anhydride was confirmed.
This polyurethane polyimide (2) solution was used for the following evaluation within the day after synthesis.

<Synthesis of branched polyurethane having carboxyl group and carbonate bond>
(Execution synthesis example 3)
Synthesis of polyurethane (1) In a reaction vessel equipped with a stirrer, a thermometer and a condenser, C-1015N (Kuraray Co., Ltd. (poly) carbonate diol and raw diol (ie, 1,9-nonanediol and 2-methyl- 1,8-octanediol), feed molar ratio of raw material diol; 1,9-nonanediol: 2-methyl-1,8-octanediol = 15: 85, hydroxyl value 112.3 mgKOH / g, 1,9 -Residual concentration of nonanediol 2.1 mass%, residual concentration of 2-methyl-1,8-octanediol 9.3 mass%) 220.4 g (0.221 mol), 2,2-dimethylolbutanoic acid (Japan) 42.2 g (0.285 mol), trimethylolpropane 2.7 g (20.1 mmol), γ-butyrolactone 51 Were charged .0g and diethylene glycol diethyl ether 90.0 g, was dissolved. The materials were heated to 100 ° C.. The temperature of the reaction solution was lowered to 90 ° C., and 133.7 g (0.510 mol) of methylenebis (4-cyclohexylisocyanate) was added dropwise over 30 minutes with a dropping funnel. After reacting at 120 ° C. for 9 hours and confirming that the isocyanate almost disappeared, 1.3 g (28.2 mmol) of ethanol was added dropwise, and further reacted at 80 ° C. for 3 hours to have a carboxyl group and a carbonate bond. A solution containing polyurethane (hereinafter referred to as polyurethane (1)) was obtained.
The viscosity of the solution containing the obtained polyurethane (1) was 101 Pa · s. The number average molecular weight of the polyurethane (1) contained in the solution containing the polyurethane (1) was 14,000, and the acid value of the polyurethane (1) was 40.0 mg-KOH / g.
Moreover, the solid content concentration in the solution containing this polyurethane (1) was 40.0% by mass.

<Synthesis of polyurethane having a carboxyl group and a carbonate bond and having a structural unit derived from dimer diol>
(Execution synthesis example 4)
Synthesis of polyurethane (2) In a reaction vessel equipped with a stirrer, a thermometer and a condenser, C-2015N (Kuraray Co., Ltd. (poly) carbonate diol and raw diol (ie 1,9-nonanediol and 2-methyl- 1,8-octanediol), feed molar ratio of raw material diol; 1,9-nonanediol: 2-methyl-1,8-octanediol = 15: 85, hydroxyl value 56.5 mgKOH / g, 1,9 -Residual concentration of nonanediol of 1.0 mass%, residual concentration of 2-methyl-1,8-octanediol of 3.6 mass%) 107.9 g (0.054 mol), 2,2-dimethylolbutanoic acid (Japan) (Made by Kasei Co., Ltd.) 32.3 g (0.218 mol), PRIPOL 2033 (98.2% by weight of dimer diol, 0.6% by weight of monool) Trimertriol 1.2 mass%, hydroxyl value; 205 mg KOH / g) 107.9 g (0.194 mol), tricyclo [5.2.1.0 ^2,6 ] decanedimethanol (Tokyo Chemical Industry Co., Ltd.) 14 .8 g (0.075 mol), 297.0 g of γ-butyrolactone and 198.0 g of diethylene glycol diethyl ether were charged and heated to 100 ° C. to dissolve all the raw materials. The temperature of the reaction solution was lowered to 90 ° C., and 142.1 g (0.542 mol) of methylenebis (4-cyclohexylisocyanate) was added dropwise over 30 minutes with a dropping funnel. After reacting at 120 ° C. for 9 hours and confirming that the isocyanate almost disappeared, 3.6 g (0.049 mol) of isobutanol (manufactured by Kyowa Hakko Chemical Co., Ltd.) was added dropwise, and the reaction was further performed at 120 ° C. for 4 hours. Then, a solution containing a polyurethane having a carboxyl group and a carbonate bond and having a structural unit derived from dimer diol (hereinafter referred to as polyurethane (2)) was obtained.
The viscosity of the solution containing the obtained polyurethane (2) was 78 Pa · s. The number average molecular weight of the polyurethane (2) contained in the solution containing the polyurethane (2) was 13,000, and the acid value of the polyurethane (2) was 40.0 mg-KOH / g.
Moreover, the solid content concentration in the solution containing this polyurethane (2) was 45.0% by mass.

(Execution synthesis example 5)
Synthesis of polyurethane (3) In a reaction vessel equipped with a stirrer, a thermometer and a condenser, C-2015N (Kuraray Co., Ltd. (poly) carbonate diol and raw diol (ie, 1,9-nonanediol and 2-methyl- 1,8-octanediol), feed molar ratio of raw material diol; 1,9-nonanediol: 2-methyl-1,8-octanediol = 15: 85, hydroxyl value 56.5 mgKOH / g, 1,9 -Residual concentration of nonanediol of 1.0 mass%, residual concentration of 2-methyl-1,8-octanediol of 3.6 mass%) 46.7 g (0.024 mol), 2,2-dimethylolbutanoic acid (Japan) 32.1 g (0.217 mol) manufactured by Kasei Co., Ltd., PRIPOL 2033 (98.2% by weight of dimer diol, 0.6% by weight of monool, Trimer triol 1.2% by mass, hydroxyl value; 205 mg KOH / g) 116.7 g (0.210 mol), UM-90 (1/1) (Ube Industries, Ltd. (poly) carbonate diol and raw diol (ie 1 , 6-hexanediol and cyclohexanedimethanol), feed molar ratio of raw material diol; 1,6-hexanediol: cyclohexanedimethanol = 1/1, hydroxyl value 122.7 mgKOH / g, 1,6-hexanediol 70.0 g (0.077 mol) of residual concentration 3.9% by mass, residual concentration of cyclohexanedimethanol 4.7% by mass), 297.0 g of γ-butyrolactone and 198.0 g of diethylene glycol diethyl ether were charged and heated to 100 ° C. All the ingredients were dissolved. The temperature of the reaction solution was lowered to 90 ° C., and 136.0 g (0.518 mol) of methylenebis (4-cyclohexylisocyanate) was added dropwise over 30 minutes with a dropping funnel. After reacting at 120 ° C. for 9 hours and confirming that the isocyanate almost disappeared, 3.6 g (0.049 mol) of isobutanol (manufactured by Kyowa Hakko Chemical Co., Ltd.) was added dropwise, and the reaction was further performed at 120 ° C. for 4 hours. And a solution containing a polyurethane having a carboxyl group and a carbonate bond and having a structural unit derived from dimer diol (hereinafter referred to as polyurethane (3)) was obtained.
The viscosity of the solution containing the obtained polyurethane (3) was 84 Pa · s. The number average molecular weight of the polyurethane (3) contained in the solution containing the polyurethane (3) was 12,000, and the acid value of the polyurethane (3) was 30.0 mg-KOH / g.
Moreover, the solid content concentration in the solution containing this polyurethane (3) was 45.0% by mass.

(Reference Synthesis Example 3)
In a reaction vessel equipped with a stirrer, a thermometer and a condenser, C-1015N (Kuraray Co., Ltd. (poly) carbonate diol and raw diol (ie 1,9-nonanediol and 2-methyl-1,8-octanediol) ), Molar ratio of raw material diol; 1,9-nonanediol: 2-methyl-1,8-octanediol = 15: 85, hydroxyl value 112.3 mgKOH / g, residual concentration of 1,9-nonanediol 2.1% by mass, 38.6 g of 2-methyl-1,8-octanediol residual concentration of 9.3% by mass) and Sovermol (registered trademark) 908 (dimer diol, manufactured by Cognis) 30.7 g, 2,2 -Charge 12.2 g of dimethylol butanoic acid (manufactured by Nippon Kasei Co., Ltd.) and 120.2 g of γ-butyrolactone and heat to 100 ° C To dissolve all of the raw materials Te. With a dropping funnel, 43.5 g of methylenebis (4-cyclohexylisocyanate) was added dropwise over 5 minutes. After completion of dropping, the reaction was carried out at 110 ° C. for 7 hours. After confirming that the isocyanate had almost disappeared, 2.0 g of isobutanol (manufactured by Wako Pure Chemical Industries, Ltd.) was added dropwise, and the reaction was further carried out at 120 ° C. for 2 hours. And a solution containing polyurethane (hereinafter referred to as polyurethane (4)) was obtained.
The number average molecular weight of the polyurethane (4) contained in the solution containing the polyurethane (4) was 12,000, and the acid value of the polyurethane (4) was 39.8 mg-KOH / g.
Moreover, the solid content concentration in the solution containing this polyurethane (4) was 50.3% by mass.

(Reference Synthesis Example 4)
In a reaction vessel equipped with a stirrer, a thermometer and a condenser, C-1015N (Kuraray Co., Ltd. (poly) carbonate diol and raw diol (ie 1,9-nonanediol and 2-methyl-1,8-octanediol) ), Molar ratio of raw material diol; 1,9-nonanediol: 2-methyl-1,8-octanediol = 15: 85, hydroxyl value 112.3 mgKOH / g, residual concentration of 1,9-nonanediol 2.1% by mass, residual concentration of 2-methyl-1,8-octanediol (9.3% by mass) 178.1 g, dioctyltin dilaurate (trade name Neostan U-810 manufactured by Nitto Kasei Co., Ltd.) 0.23 g, γ -191.3 g of butyrolactone and 33.8 g of diethylene glycol diethyl ether were charged and heated to 80 ° C. It was dissolved fee. With a dropping funnel, 47.0 g of methylenebis (4-cyclohexylisocyanate) was added dropwise over 5 minutes. After completion of the dropwise addition, the reaction was carried out at 80 ° C. for 4 hours. After confirming that the isocyanate had almost disappeared, 2.0 g of isobutanol (manufactured by Wako Pure Chemical Industries, Ltd.) was added dropwise, and the reaction was further carried out at 80 ° C. for 1 hour. And a solution containing polyurethane (hereinafter referred to as polyurethane (5)) was obtained.
The number average molecular weight of the polyurethane (5) contained in the solution containing the polyurethane (5) was 19,000, and the acid value of the polyurethane (5) was 0 mg-KOH / g.
Moreover, the solid content concentration in the solution containing this polyurethane (5) was 50.1% by mass.

（式中、ｌは、０または１以上の整数を表す。）
１００質量部の主剤組成物Ａ１及び９，６５質量部の硬化剤溶液Ｂ１及び消泡剤（モメンティブ・パフォーマンス・マテリアルズ社製 商品名：ＴＳＡ７５０Ｓ）０．５質量部を混合し、スパチュラを用いて、十分に撹拌混合した。その後、チクソトロピー指数を１．３に合わせるのに必要量のγ−ブチロラクトン：ジエチレングリコールジエチルエーテル＝８５：１５（質量比）の混合溶媒を添加して、粘度調整を行い、熱硬化性組成物（以下、熱硬化性組成物Ｇ１と記す。）を得た。(Example formulation 1)
1,8-diazabicyclo (4.5.0) undecene-7 (hereinafter referred to as DBU) as a curing accelerator with respect to 100 parts by mass of polyurethane polyimide (1) in a solution containing polyurethane polyimide (1) ( 1 part by mass of San Apro Co., Ltd.) was added and stirred and mixed uniformly. Further, 7 parts by mass of silica powder (Nippon Aerosil Co., Ltd., trade name: Aerosil R972) and 5 parts by mass of talc (Nippon Talc Co., Ltd., trade name: SG2000) were added, first roughly kneaded, and then triple roll mill (Inoue Co. A composition (hereinafter referred to as a main agent composition A1) containing polyurethane polyimide (1) uniformly mixed by repeating this kneading three times using a model manufactured by Seisakusho: S-43 / 4 × 11). .)
Further, in a container equipped with a stirrer, a thermometer, and a condenser, 300 g of an epoxy resin having a structure represented by the following formula (2) (DIC Corporation grade name; HP-7200H epoxy equivalent 278 g / eq), 180 g of γ-butyrolactone and 120 g of diethylene glycol diethyl ether was added and stirring was started. While continuing stirring, the temperature in the container was raised to 70 ° C. using an oil bath. After the internal temperature was raised to 70 ° C., stirring was continued for 30 minutes. Then, it confirmed that HP-7200H melt | dissolved completely, it cooled to room temperature, and the HP-7200H containing solution (henceforth hardening agent solution B1) with a density | concentration of 50 mass% was acquired.

(In the formula, l represents 0 or an integer of 1 or more.)
100 parts by mass of the main agent composition A1 and 9,65 parts by mass of the curing agent solution B1 and 0.5 part by mass of an antifoaming agent (product name: TSA750S manufactured by Momentive Performance Materials) are mixed, and a spatula is used. , Mixed well with stirring. Thereafter, a viscosity adjustment is performed by adding a mixed solvent of γ-butyrolactone: diethylene glycol diethyl ether = 85: 15 (mass ratio) necessary for adjusting the thixotropy index to 1.3. , Written as thermosetting composition G1).

(Example of formulation 2)
In a solution containing polyurethane polyimide (2), 7.9 parts by mass of Aerosil 380 (manufactured by Nippon Aerosil Co., Ltd.) and 1 part by weight of DBU (manufactured by Sun Apro Co., Ltd.) with respect to 100 parts by mass of polyurethane polyimide (2) Part is first roughly kneaded, then, using a three roll mill (manufactured by Inoue Seisakusho Co., Ltd. Model: S-43 / 4 × 11), this kneading is repeated three times to perform main kneading, and polyurethane polyimide (2) is obtained. A composition containing the composition (hereinafter referred to as main agent composition A2) was obtained.
To 100 parts by mass of the main agent composition A2, 20 parts by mass of a curing agent solution B1 and 0.5 part by mass of an antifoaming agent (trade name: TSA750S manufactured by Momentive Performance Materials) are added, and γ-butyrolactone: A thermosetting composition diluted with diethylene glycol diethyl ether = 85: 15 (mass ratio) and containing polyurethane polyimide (2) having a viscosity of 35 Pa · s, a thixotropy index of 2.2, and a nonvolatile content of 40% by mass (hereinafter, thermosetting) To be referred to as sex composition G2.).

(Example formulation 3)
111.1 parts by mass of the solution containing the polyurethane (1), 5.0 parts by mass of silica powder (trade name; Aerosil R974, manufactured by Nippon Aerosil Co., Ltd.), and melamine (manufactured by Nissan Chemical Industries, Ltd.) as a curing accelerator 36 parts by mass were mixed, and using a three-roll mill (manufactured by Inoue Seisakusho Co., Ltd. Model: S-43 / 4 × 11), kneading was repeated three times to perform main kneading, and a composition containing polyurethane (1) ( Hereinafter, referred to as main agent composition A3).
22.7 parts by mass of the curing agent solution B1 and 0.60 parts by mass of the antifoaming agent (trade name; TSA750S manufactured by Momentive Performance Materials) are mixed with 100 parts by mass of the main agent composition A3, and the spatula is mixed. Was thoroughly stirred and mixed. Thereafter, a viscosity adjustment is performed by adding a mixed solvent of γ-butyrolactone: diethylene glycol diethyl ether = 85: 15 (mass ratio) necessary for adjusting the thixotropy index to 1.3. , Written as thermosetting composition G3).

(Example formulation 4)
111.1 parts by mass of the solution containing the polyurethane (2), 5.0 parts by mass of silica powder (trade name; Aerosil R974, manufactured by Nippon Aerosil Co., Ltd.), and melamine (manufactured by Nissan Chemical Industries, Ltd.) as a curing accelerator 36 parts by mass are mixed, using a three-roll mill (manufactured by Inoue Seisakusho Co., Ltd. Model: S-43 / 4 × 11), this kneading is repeated three times to perform main kneading, and a composition containing polyurethane (2) ( Hereinafter, referred to as main agent composition A4).
A spatula is mixed with 25.5 parts by mass of the curing agent solution B1 and an antifoaming agent (product name: TSA750S, manufactured by Momentive Performance Materials) with respect to 100 parts by mass of the main agent composition A4. Was thoroughly stirred and mixed. Thereafter, a viscosity adjustment is performed by adding a mixed solvent of γ-butyrolactone: diethylene glycol diethyl ether = 60: 40 (mass ratio) necessary for adjusting the thixotropy index to 1.3. , Written as thermosetting composition G4).

(Example formulation 5)
111.1 parts by mass of the solution containing the polyurethane (3), 5.0 parts by mass of silica powder (trade name; Aerosil R974, manufactured by Nippon Aerosil Co., Ltd.), and melamine (manufactured by Nissan Chemical Industries, Ltd.) as a curing accelerator 36 parts by mass were mixed, using a three-roll mill (manufactured by Inoue Seisakusho Co., Ltd. Model: S-43 / 4 × 11), kneading was repeated three times to perform main kneading, and a composition containing polyurethane (3) ( Hereinafter, referred to as main agent composition A5).
Spatula is mixed with 19.1 parts by weight of the curing agent solution B1 and 0.60 parts by weight of an antifoaming agent (product name: TSA750S, manufactured by Momentive Performance Materials) with respect to 100 parts by weight of the main agent composition A5. Was thoroughly stirred and mixed. Thereafter, a viscosity adjustment is performed by adding a mixed solvent of γ-butyrolactone: diethylene glycol diethyl ether = 60: 40 (mass ratio) necessary for adjusting the thixotropy index to 1.3, and a thermosetting composition (hereinafter referred to as a thermosetting composition). , Written as thermosetting composition G5).

(Example formulation 6)
A spatula is mixed with 30.3 parts by mass of a curing agent solution B1 and an antifoaming agent (trade name; TSA750S, manufactured by Momentive Performance Materials) of 100 parts by mass of the main agent composition A3. Was thoroughly stirred and mixed. Thereafter, a viscosity adjustment is performed by adding a mixed solvent of γ-butyrolactone: diethylene glycol diethyl ether = 85: 15 (mass ratio) necessary for adjusting the thixotropy index to 1.3. , Written as thermosetting composition G6).

(Example formulation 7)
A spatula is mixed with 34.0 parts by mass of the curing agent solution B1 and an antifoaming agent (trade name; TSA750S, manufactured by Momentive Performance Materials) with respect to 100 parts by mass of the main agent composition A4. Was thoroughly stirred and mixed. Thereafter, a viscosity adjustment is performed by adding a mixed solvent of γ-butyrolactone: diethylene glycol diethyl ether = 60: 40 (mass ratio) necessary for adjusting the thixotropy index to 1.3, and a thermosetting composition (hereinafter referred to as a thermosetting composition). , Written as thermosetting composition G7).

(Example of formulation 8)
A spatula is mixed with 25.5 parts by mass of the curing agent solution B1 and 0.60 parts by mass of an antifoaming agent (trade name; TSA750S, manufactured by Momentive Performance Materials) with respect to 100 parts by mass of the main agent composition A5. Was thoroughly stirred and mixed. Thereafter, a viscosity adjustment is performed by adding a mixed solvent of γ-butyrolactone: diethylene glycol diethyl ether = 60: 40 (mass ratio) necessary for adjusting the thixotropy index to 1.3, and a thermosetting composition (hereinafter referred to as a thermosetting composition). , Written as thermosetting composition G8).

(Comparative Formulation Example 1)
With respect to 100 parts by mass of the main agent composition A1, Celoxide 2021P (manufactured by Daicel Chemical Industries, (3 ', 4'-epoxycyclohexane) methyl-3,4-epoxycyclohexanecarboxylate, epoxy equivalent 126 g / eq) 4 .2 parts by mass and an antifoaming agent (product name: TSA750S, manufactured by Momentive Performance Materials) 0.5 part by mass is uniformly mixed with the composition containing the polyurethane polyimide (1), and the polyurethane polyimide (1) A thermosetting composition (hereinafter referred to as thermosetting composition H1) was obtained.

(Comparative Formulation Example 2)
For 100 parts by mass of the main agent composition A2, 10 parts by mass of YH-434 (trade name of amine-type epoxy resin manufactured by Tohto Kasei Co., Ltd., epoxy equivalent 120 g / eq) and TSA750S (manufactured by Momentive Performance Materials) Anti-foaming product name) Thermosetting containing 0.5 parts by mass, diluted with γ-butyrolactone and containing polyurethane polyimide (2) having a viscosity of 35 Pa · s, a thixotropy index of 2.4, and a nonvolatile content of 40% by mass A composition (hereinafter referred to as a thermosetting composition H2) was obtained.

(Comparative Formulation Example 3)
To a container equipped with a stirrer and a condenser, 300 parts by mass of jER828EL (Bisphenol A type epoxy resin, epoxy equivalent 190 g / eq, manufactured by Japan Epoxy Resin Co., Ltd.) and 300 parts by mass of diethylene glycol monoethyl ether acetate were added, and stirring was started. Stirring was continued for 1 hour. Thereafter, it was confirmed that jER828EL was completely dissolved, and a jER828EL-containing solution having a concentration of 50% by mass was obtained. This solution is designated as a curing agent solution B2.
111.1 parts by mass of the solution containing the polyurethane (4), 5.0 parts by mass of silica powder (trade name; Aerosil R974, manufactured by Nippon Aerosil Co., Ltd.), and melamine (manufactured by Nissan Chemical Industries, Ltd.) as a curing accelerator 36 parts by mass were mixed, and using a three-roll mill (manufactured by Inoue Seisakusho Co., Ltd. Model: S-43 / 4 × 11), kneading was repeated three times to perform main kneading, and a composition containing polyurethane (4) Hereinafter, referred to as main agent composition A6).
To 100 parts by mass of the main agent composition A6, 14.2 parts by mass of the curing agent solution B2 and 0.60 parts by mass of an antifoaming agent (trade name; TSA750S, manufactured by Momentive Performance Materials) are mixed, and a spatula Was thoroughly stirred and mixed. Thereafter, a viscosity adjustment is performed by adding a mixed solvent of γ-butyrolactone: diethylene glycol monoethyl ether acetate = 1: 1 (mass ratio) necessary for adjusting the thixotropy index to 1.3, and the thermosetting composition. (Hereinafter, referred to as thermosetting composition H3).

(Comparative Formulation Example 4)
88.9 parts by mass of the solution containing the polyurethane (5), 5.0 parts by mass of silica powder (trade name; Aerosil R974, manufactured by Nippon Aerosil Co., Ltd.), and melamine (manufactured by Nissan Chemical Industries, Ltd.) as a curing accelerator 0. 36 parts by mass are mixed, using a three-roll mill (manufactured by Inoue Seisakusho Co., Ltd. Model: S-43 / 4 × 11), the kneading is repeated three times to perform main kneading, and a composition containing polyurethane (5) ( Hereinafter, referred to as main agent composition A7).
82.7 parts by mass of the main agent composition A7 is mixed with 22.7 parts by mass of the curing agent solution B1 and 0.60 parts by mass of the defoaming agent (trade name; TSA750S manufactured by Momentive Performance Materials). The mixture was thoroughly stirred using a spatula. Thereafter, a viscosity adjustment is performed by adding a mixed solvent of γ-butyrolactone: diethylene glycol diethyl ether = 85: 15 (mass ratio) necessary for adjusting the thixotropy index to 1.3. , Referred to as thermosetting composition H4).

(Examples 1-8, Comparative Examples 1-3)
As described in Table 1, polyimide and tin plating treatment were performed by the methods described later using the thermosetting composition G1 to thermosetting composition G8 and the thermosetting composition H1 to thermosetting composition H4, respectively. Evaluation of adhesion to copper subjected to, evaluation of warpage and long-term electrical insulation reliability were performed. The results are shown in Table 1.

Evaluation of adhesion to polyimide and tin-plated copper Flexible copper-clad laminate (grade name; Esperflex copper thickness: 8 μm, polyimide thickness; 38 μm, manufactured by Sumitomo Metal Mining Co., Ltd.) The polyimide film (Kapton (registered trademark) 300H, manufactured by Toray DuPont Co., Ltd.) is coated with the thermosetting composition G1 by screen printing to a thickness of 15 μm (the thickness after drying). ) And placed in an 80 ° C. hot air circulation dryer for 30 minutes, and then placed in a 120 ° C. hot air circulation dryer for 120 minutes for curing. In this cured coating film, 100 grid patterns were cut at 1 mm intervals, a tape cut to a length of about 75 mm was bonded to the grid portion, and a peeling tape (a product specified in JIS Z 1522) was 60 °. The film was peeled off at an angle near 0.5 to 0.5 to 1.0 seconds.
In addition, the peeling tape evaluated by the following reference | standard using the product made from Nitto Denko Corporation.
○: When 80 or more grids remain,
△: When the number of grids is 50 or more and less than 80,
×: When the number of grids remains less than 50.
The results are shown in Table 1.
Moreover, the same evaluation was performed using the thermosetting composition G2 to the thermosetting composition G8 and the thermosetting composition H1 to the thermosetting composition H4.
The results are also shown in Table 1.

Evaluation of warpage The thermosetting composition G1 was applied to a substrate by screen printing, placed in an 80 ° C hot air circulation dryer for 30 minutes, and then placed in a 120 ° C hot air circulation dryer for 60 minutes to cure. I let you. A 38 μm-thick polyimide film [Kapton (registered trademark) 150EN, manufactured by Toray DuPont Co., Ltd.] was used as the substrate.
About the coating film which apply | coated the thermosetting composition and hardened | cured using the dryer, it cut with a circle cutter to 50 mmphi. What is cut into a circle exhibits a deformation in which the vicinity of the center warps in a convex or concave shape. After leaving the test piece at a temperature of 23 ± 0.5 ° C. and a humidity of 60 ± 5% RH for 12 hours or more, the test piece is left in a convex state, and the portion that is most warped from the plane, The height of the warp from the plane was measured using a length meter and averaged at two locations that were symmetric with respect to the center of. The sign represents the direction of warping, and when left in a downwardly convex state, the case where the cured film is on the upper side with respect to the polyimide film is “+”, and the case where the cured film is on the lower side is “−”.
The results are shown in Table 1.
Moreover, the same evaluation was performed using the thermosetting composition G2 to the thermosetting composition G8 and the thermosetting composition H1 to the thermosetting composition H4.
The results are also shown in Table 1.

Evaluation of flexibility Flexible copper-clad laminate (manufactured by Sumitomo Metal Mining Co., Ltd. grade name: Esperflex copper thickness: 8 μm, polyimide thickness: 38 μm) on copper of 75 mm width and 110 mm length, after curing The thermosetting composition G1 was applied by clean printing so that the thickness of the coating film became 15 μm, held at room temperature for 10 minutes, and cured by placing it in a 120 ° C. hot air circulating dryer for 60 minutes. The PET film on the back of the prepared test piece was peeled off, cut into a strip shape with a width of 10 mm with a cutter knife, bent about 180 degrees so that the coating surface was on the outside, and 0.5 ± 0 using a compressor. Compressed at 2 MPa for 3 seconds. The bent part was bent and observed with a 30-fold microscope to confirm the presence or absence of cracks.
The results are shown in Table 1.
Moreover, the same evaluation was performed using the thermosetting composition G2 to the thermosetting composition G8 and the thermosetting composition H1 to the thermosetting composition H4.
The results are also shown in Table 1.

Long-term electrical insulation reliability evaluation (1)
A substrate having a fine comb pattern shape described in JPCA-ET01 manufactured by etching a flexible copper-clad laminate (Sumitomo Metal Mining Co., Ltd. grade name; Esperflex copper thickness: 8 μm, polyimide thickness: 38 μm) Width / width between copper wirings = 15 μm / 15 μm) A thickness of 15 μm from the polyimide surface after drying the thermosetting composition G1 by screen printing on a flexible wiring board subjected to tin plating (after drying) Then, it was placed in a hot air circulating dryer at 80 ° C. for 30 minutes, and then cured by placing it in a 120 ° C. hot air circulating dryer for 120 minutes.
Using this test piece, a bias voltage of 60 V was applied, and a constant temperature and humidity test under the conditions of a temperature of 120 ° C. and a humidity of 85% RH was performed using MIGRATION TESTER MODEL MIG-8600 (manufactured by IMV). Table 1 shows resistance values at 1 hour, 100 hours, 200 hours, 300 hours, and 400 hours after starting the temperature and humidity steady state test.
Moreover, the same evaluation was performed using the thermosetting composition G2 to the thermosetting composition G8 and the thermosetting composition H1 to the thermosetting composition H4.
The results are also shown in Table 1.

Long-term electrical insulation reliability evaluation (2)
A substrate having a fine comb pattern shape described in JPCA-ET01 manufactured by etching a flexible copper-clad laminate (Sumitomo Metal Mining Co., Ltd. grade name; Esperflex copper thickness: 8 μm, polyimide thickness: 38 μm) Width / width between copper wirings = 15 μm / 15 μm) A thickness of 15 μm from the polyimide surface after drying the thermosetting composition G1 by screen printing on a flexible wiring board subjected to tin plating (after drying) Then, it was placed in a hot air circulating dryer at 80 ° C. for 30 minutes, and then cured by placing it in a 120 ° C. hot air circulating dryer for 120 minutes.
Using this test piece, a bias voltage of 60 V was applied, and a temperature and humidity steady test under conditions of a temperature of 85 ° C. and a humidity of 85% RH was performed using MIGRATION TESTER MODEL MIG-8600 (manufactured by IMV). Table 1 shows the resistance values after 10 hours, 500 hours, 1000 hours, and 2000 hours after the start of the temperature and humidity steady test.
Moreover, the same evaluation was performed using the thermosetting composition G2 to the thermosetting composition G8 and the thermosetting composition H1 to the thermosetting composition H4.
The results are also shown in Table 1.

  From the results of Table 1, by using the thermosetting composition of the present invention (I), a novel composition capable of expressing long-term electrical insulation characteristics while maintaining a high level of resistance value and the composition were cured. The hardened | cured material obtained can be provided.

  The thermosetting composition for a protective film of a wiring board of the present invention is suitably used for production of a flexible wiring board.

Claims (15)

Thermosetting for protective film of wiring board having epoxy group-containing compound having tricyclodecane structure, polyurethane having functional group capable of reacting with epoxy group and having structural unit represented by formula (1) and solvent as essential components Sex composition.

(In the formula, R ¹ represents an alkylene group having 3 to 18 carbon atoms, and n represents an integer of 1 or more.) The epoxy group-containing compound having a tricyclodecane structure has a tricyclo [5.2.1.0 ^2,6 ] decane structure or a tricyclo [3.3.1.1 ^3,7 ] decane structure, and an aromatic ring The thermosetting composition for a protective film for a wiring board according to claim 1, which is an epoxy group-containing compound having a structure. The thermosetting composition for a protective film of a wiring board according to claim 2, wherein the epoxy group-containing compound having a tricyclodecane structure is a compound represented by the formula (2).

(In the formula, l represents 0 or an integer of 1 or more.)   The polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by formula (1) has a functional group capable of reacting with an epoxy group and having a structural unit represented by formula (1). Furthermore, it is the polyurethane polyimide which has an imide bond, The thermosetting composition for protective films of the wiring board of any one of Claims 1-3 characterized by the above-mentioned.   The thermosetting composition for a protective film of a wiring board according to any one of claims 1 to 4, wherein the functional group capable of reacting with an epoxy group is a carboxyl group.   The thermosetting composition for a protective film of a wiring board according to any one of claims 1 to 4, wherein the functional group capable of reacting with an epoxy group is an acid anhydride group. A polyurethane polyimide having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) and further having an imide bond is obtained by reacting the following components (a) to (d): The thermosetting composition for a protective film for a wiring board according to claim 4, wherein the thermosetting composition is a polyurethane polyimide.
Component (a) diisocyanate,
Component (b) (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms,
Component (c) Diol having a carboxyl group, and Component (d) A bifunctional hydroxyl-terminated imide represented by the formula (3).

Wherein R ² and R ³ each independently represents a divalent aliphatic or aromatic hydrocarbon group, and Y ¹ represents a tetravalent organic group derived from a tetracarboxylic acid or an acid anhydride group thereof. X ¹ represents a divalent organic group derived from diamine or diisocyanate, and m is an integer of 0 to 20.) A polyurethane polyimide having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) and further having an imide bond is selected from the group consisting of the formulas (4) to (6). The thermosetting composition for a protective film of a wiring board according to claim 4, which is a polyurethane polyimide having one type of structural unit.

In the formula, a plurality of R ⁴ are each independently an alkylene group having 3 to 18 carbon atoms, a plurality of R ⁵ are each independently an alkylene group having 3 to 18 carbon atoms, and a and b are Each is independently an integer of 1 to 20, and the plurality of X ² are each independently a divalent organic group.

In the formula, a plurality of R ⁶ are each independently a C 3-18 alkylene group, a plurality of R ⁷ are each independently a C 3-18 alkylene group, and c and d are each independently integers of 1 to 20, a plurality of ^{X 3} are each independently a divalent organic _group, ^{Y 2} is CH 2, SO ₂ or O.

In the formula, a plurality of R ⁸ are each independently an alkylene group having 3 to 18 carbon atoms, a plurality of R ⁹ are each independently an alkylene group having 3 to 18 carbon atoms, and e and f are Each independently represents an integer of 1 to 20, a plurality of X ⁴ are each independently a divalent organic group, and Y ³ is any one of the following formulas (7) to (33): .

A polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) reacts with the following components (a), (b), (c) and (e): The thermosetting composition for a protective film of a wiring board according to any one of claims 1 to 3, which is a polyurethane obtained.
Component (a) diisocyanate,
Component (b) (poly) carbonate polyol having an organic residue derived from a diol having 3 to 18 carbon atoms,
Component (c) a diol having a carboxyl group,
Component (e) A compound having 3 or more hydroxyl groups in one molecule.   The polyurethane having a functional group capable of reacting with an epoxy group and having a structural unit represented by the formula (1) is a polyurethane further containing an organic residue derived from a dimer diol. The thermosetting composition for a protective film for a wiring board according to any one of 1 to 3, 5, 6, and 9.   The solvent is a mixed solvent containing at least one solvent having a boiling point of 170 ° C. or more and less than 200 ° C. under atmospheric pressure and at least one solvent having a boiling point of 200 ° C. to 220 ° C. under atmospheric pressure. The thermosetting composition for a protective film for a wiring board according to any one of claims 1 to 10. The solvent having a boiling point of 170 ° C. or more and less than 200 ° C. under atmospheric pressure is at least one selected from the following group A, and the solvent having a boiling point of 200 ° C. to 220 ° C. under atmospheric pressure is the following group B: It is at least 1 sort (s) chosen from the inside, The thermosetting composition for protective films of the wiring board of Claim 11 characterized by the above-mentioned.
Group A: diethylene glycol dimethyl ether (boiling point 162 ° C.), diethylene glycol diethyl ether (boiling point 189 ° C.), diethylene glycol ethyl methyl ether (boiling point 176 ° C.), dipropylene glycol dimethyl ether (boiling point 171 ° C.), 3-methoxybutyl acetate (boiling point 171) ° C), ethylene glycol monobutyl ether acetate (boiling point 192 ° C)
Group B: Diethylene glycol butyl methyl ether (boiling point 212 ° C.), tripropylene glycol dimethyl ether (boiling point 215 ° C.), triethylene glycol dimethyl ether (boiling point 216 ° C.), ethylene glycol dibutyl ether (boiling point 203 ° C.), diethylene glycol monoethyl ether acetate (boiling point) 217 ° C.), γ-butyrolactone (boiling point 204 ° C.).   The protective film of the wiring board obtained by hardening | curing the thermosetting composition for protective films of the wiring board of any one of Claims 1-12.   A part of or all of the surface of the flexible wiring board in which the wiring is formed on the flexible substrate is covered with the protective film of the wiring board according to claim 13. A flexible wiring board covered with a film.   A printed film is formed on the pattern by printing the thermosetting composition for a protective film of a wiring board according to any one of claims 1 to 12 on a tinned wiring pattern portion of a flexible wiring board. A method for producing a flexible wiring board covered with a protective film, wherein the printed film is heated and cured at 80 to 130 ° C. to form a protective film.