JP2021042369A - Curable resin composition, dry film and cured product thereof, and electronic component including the cured product - Google Patents

Abstract

To provide a curable resin composition improved in developability and resolution without deteriorating heat resistance and chemical resistance, a dry film containing the same, a cured product thereof, and a printed wiring board including the cured product.SOLUTION: The curable resin composition is obtained which contains (A) an amide-imide resin, (B) a compound having an ethylenic double bond, and (C) a photopolymerization initiator. The amide-imide resin (A) is a reaction product of a tricarboxylic acid anhydride and an isocyanurate type polyisocyanate synthesized from an isocyanate having an aliphatic structure and has a number average molecular weight of 500-1,000.SELECTED DRAWING: None

Description

The present invention relates to a curable resin composition, for example, a curable resin composition for an interlayer insulating material used when rewiring a printed wiring board, particularly a curable resin composition and a dry film of a curable resin composition. And the cured product, and electronic parts containing this cured product.

Conventionally, as the interlayer insulating material of the printed wiring board, various properties such as heat resistance of the cured product have been improved by using a curable resin composition containing an amidimide resin. In particular, when the amidoimide resin contains a carboxyl group, the coating film of the curable resin composition can be alkaline-developed. However, even when an amidoimide resin containing a carboxyl group is used, the developability or resolution is not always good (for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 2003-221249

Therefore, in a curable resin composition containing an amideimide resin, when a large amount of a carboxyl group-containing resin is contained in the amideimide resin in order to improve the resolution, the glass transition temperature (Tg) tends to decrease. , The chemical resistance of the obtained cured product may decrease. In particular, when the cured product is used in a form in which a cured product is contained in a part of the substrate of an electronic component, the substrate surface is cleaned with an acid or an alkali during the fabrication of the substrate, or the substrate is cleaned with a solvent during mounting. Chemical resistance is essential. However, until now, a resin composition having excellent heat resistance, developability, resolution, and chemical resistance has not been obtained.

Therefore, the present invention relates to a curable resin composition having improved developability and resolution without deteriorating heat resistance and chemical resistance, a dry film containing the same, a cured product thereof, and a print containing the cured product thereof. An object is to provide a wiring board.

As a result of diligent studies by the present inventors in view of the above objectives,
(A) Amidoimide resin and
(B) A compound having an ethylenic double bond and
(C) Photopolymerization initiator and
The amidoimide resin (A) is a reaction product of an isocyanurate-type polyisocyanate synthesized from an isocyanate having an aliphatic structure and a tricarboxylic acid anhydride, and has a number average molecular weight of 500 to 1000. A characteristic curable resin composition has been found, and the present invention has been completed.

The tricarboxylic acid anhydride of the present invention preferably has an aliphatic structure.

The curable resin composition of the present invention preferably further contains (D) a thermosetting resin.

The above-mentioned problems of the present invention are solved by a dry film containing a resin layer composed of the above-mentioned curable resin composition, a cured product of the curable resin composition, and an electronic component containing the cured product.

According to the present invention, a curable resin composition having excellent heat resistance and chemical resistance after curing and improved developability and resolution, a dry film thereof, a cured product thereof, and a printed wiring board containing the cured product thereof. You can get a board.

The curable resin composition of the present invention contains (A) an amidoimide resin, (B) a compound having an ethylenic double bond, and (C) a photopolymerization initiator, and (A) the amidoimide resin is a fat. It is a reaction product of an isocyanurate-type polyisocyanate synthesized from an isocyanate having a group structure and tricarboxylic acid anhydride, and has a number average molecular weight of 500 to 1000.
Since the curable resin composition of the present invention has the above-mentioned structure, it exhibits excellent developability when subjected to development with an alkaline developer, and the resolution of the cured product obtained thereby is extremely good. Will be done. Further, the cured product obtained from this curable resin composition is also excellent in heat resistance, cured coating film strength, and chemical resistance. Therefore, in the necessary application of both delicate resolution and durability (heat resistance, strength, chemical resistance) of the coating film, for example, in application as an interlayer insulating material such as a printed wiring board or an insulating material for rewiring. It is significant.

Hereinafter, each component of the curable resin composition will be described in detail.

[(A) Amidoimide resin]
The curable resin composition of the present invention contains (A) amidoimide resin.
The amidoimide resin (A) is produced by reacting an isocyanurate-type polyisocyanate synthesized from an isocyanate having an aliphatic structure with a tricarboxylic acid anhydride, and has a number average molecular weight in the range of 500 to 1000. Is used. That is, the (A) amidoimide resin used in the present invention forms an imide bond directly from the above-mentioned isocyanurate-type polyisocyanate and tricarboxylic acid anhydride, as compared with the synthesis via the polyamic acid intermediate of the prior art. It is possible to synthesize an amidoimide resin having good material stability, reproducibility and solubility, and excellent transparency. Further, by setting the number average molecular weight of the (A) amidimide resin in the range of 500 to 1000, the developability and the resolvability are particularly improved.

[Isocyanurate type polyisocyanate]
The above-mentioned isocyanurate-type polyisocyanate used as a synthetic raw material for the (A) amidoimide resin is an aliphatic isocyanurate, that is, an aliphatic linear isocyanate (for example, hexamethylene diisocyanate or trimethylhexamethylene diisocyanate) or an alicyclic isocyanate (isophorone). It is synthesized from diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylene diisocyanate, norbornan diisocyanate, hydrogenated diphenylmethane diisocyanate).

Specific examples of isocyanurate-type polyisocyanates include
HDI3N: Isocyanurate-type triisocyanate synthesized from hexamethylene diisocyanate,
HTMDI3N: isocyanurate-type triisocyanate synthesized from trimethylhexamethylene diisocyanate,
IPDI3N: Isocyanurate-type triisocyanate synthesized from isophorone diisocyanate,
HTDI3N: Isocyanurate-type triisocyanate synthesized from hydrogenated tolylene diisocyanate,
HXDI3N: Isocyanurate-type triisocyanate synthesized from hydrogenated xylene diisocyanate,
NBDI3N: isocyanurate-type triisocyanate synthesized from norbornane diisocyanate, and HMDI3N: isocyanurate-type triisocyanate synthesized from hydrogenated diphenylmethane diisocyanate.
Each of the above triisocyanurates may be used alone or in combination.

The isocyanate used as a raw material for the (A) amidoimide resin is preferably an alicyclic isocyanate, particularly isophorone diisocyanate, and by using this, a Tg is particularly improved and a cured coating film having excellent thermal characteristics can be obtained. Further, since the isocyanate having the aliphatic structure does not have an aromatic ring structure, the amideimide resin according to the present invention obtained thereby has high transparency.

[Tricarboxylic acid anhydride]
Examples of the tricarboxylic acid anhydride which is another reaction raw material of the (A) amidoimide resin include tricarboxylic acid anhydrides having an aromatic structure, for example, trimetic anhydride, 1,2,4-benzenetricarboxylic acid 1,2 anhydride and the like. Tricarboxylic acid anhydrides having an aliphatic structure (including an aliphatic linear structure or an alicyclic structure), for example, cyclohexanetricarboxylic acid anhydride, methylcyclohexanetricarboxylic acid anhydride, cyclohexcentricarboxylic acid anhydride, and the like. Methylcyclohexentricarboxylic anhydride and the like can be mentioned. As the tricarboxylic acid anhydride, one having an aliphatic structure is preferable, and cyclohexanetricarboxylic acid anhydride is particularly preferably used. The isocyanurate-type polyisocyanate and the tricarboxylic acid anhydride preferably have a structure that does not have an aromatic ring structure. As a result, the obtained amidoimide resin according to the present invention has high transparency, and by extension, the cured product obtained from the curable resin composition of the present invention containing the same also has high transparency.

Cyclohexanetricarboxylic acid anhydride is given by the following formula (1).

で表され、その具体例としてのシクロヘキサン−１，３，４−トリカルボン酸-３，４−無水物、シクロヘキサン−１，３，５−トリカルボン酸-３，５−無水物、シクロヘキサン−１，２，３−トリカルボン酸-２，３−無水物等、特に、シクロヘキサン−１，３，４−トリカルボン酸-３，４−無水物が好ましく用いられる。
すなわち、このような脂肪族トリカルボン酸無水物を（Ａ）アミドイミド樹脂の原料とすることにより、本発明の硬化物の耐熱性が一層優れたものとされる。

Cyclohexane-1,3,4-tricarboxylic acid-3,4-anhydride, cyclohexane-1,3,5-tricarboxylic acid-3,5-anhydride, cyclohexane-1,2 , 3-Tricarboxylic acid-2,3-anhydride and the like, particularly cyclohexane-1,3,4-tricarboxylic acid-3,4-anhydride is preferably used.
That is, by using such an aliphatic tricarboxylic acid anhydride as a raw material for the (A) amidoimide resin, the heat resistance of the cured product of the present invention is further improved.

Further, the above-mentioned tricarboxylic acid anhydride is used as a raw material for producing the (A) amidoimide resin, and in some cases, a bifunctional dicarboxylic acid compound such as an aliphatic or aromatic dicarboxylic acid such as sebacic acid, phthalic acid or fumaric acid is used. , Maleic acid and their acid anhydrides can also be used in combination.

When the carboxylic acid component of the tricarboxylic acid anhydride reacts with the isocyanate component in the isocyanurate-type polyisocyanate, imides and amides are formed, and the resin of the present invention becomes an amide imide resin. Further, when the isocyanurate-type polyisocyanate is reacted with the tricarboxylic acid anhydride, an imide bond is formed from the acid anhydride group and the isocyanate group, and an amide bond is formed from the carboxyl group and the isocyanate group. When the tricarboxylic acid anhydride group is reacted with the polyisocyanate group at a ratio that leaves the carboxylic acid (carboxyl group) component of the acid anhydride, the obtained polyamideimide resin has a carboxy group. This carboxy group reacts with a polymerizable group such as an epoxy group of an epoxy resin contained in the curable resin composition of the present invention described later to form a crosslinked structure of the cured product. In the reaction of tricarboxylic acid anhydride and triisocyanate, the above-mentioned two types of reactions, amidation and imidization, can be considered, but since the reaction rate is fast, tricarboxylic acid is selected at the acid anhydride group. Form an imide.

The isocyanurate-type polyisocyanate synthesized from an isocyanate having an aliphatic structure and the tricarboxylic acid anhydride having an aliphatic structure are the number of moles of the isocyanate group of the isocyanurate-type polyisocyanate synthesized from the isocyanate having the aliphatic structure. The ratio of (N) to the total number of moles of the carboxy group (M1) and the acid anhydride group (M2) of the tricarboxylic acid anhydride [(M1) + (M2)) / (N)] When the reaction is carried out so as to have a value of 1.1 to 1, the polarity in the reaction system becomes high and the reaction proceeds to lubrication, isocyanate groups do not remain, and the stability of the obtained polyimide resin is good. Tricarbonate It is preferable because the residual amount of the acid anhydride is small and the problem of separation such as recrystallization is unlikely to occur. Of these, 1.2 to 2 is more preferable. In the present invention, the acid anhydride group refers to a -CO-O-CO- group obtained by intramolecular dehydration condensation of two carboxylic acid molecules.

The imidization reaction is preferably carried out by mixing one or more kinds of isocyanates having an aliphatic structure and one or more kinds of tricarboxylic acid anhydrides in a solvent or no solvent and raising the temperature while stirring. .. The reaction temperature is preferably 50 ° C. to 250 ° C., particularly preferably 70 ° C. to 180 ° C. By setting the reaction temperature to such a level, the reaction rate is increased, and side reactions and decomposition are unlikely to occur. In the reaction, the acid anhydride group and the isocyanate group form an imide group with decarboxylation. The progress of the reaction can be tracked by analytical means such as infrared spectrum, acid value, and quantification of isocyanate groups. The infrared spectrum, 2270 cm ^-1 which is the characteristic absorption of an isocyanate group was reduced as the reaction further acid anhydride group is reduced with a characteristic absorption at 1860 cm ^-1 and 850 cm ^-1. On the other hand, the absorption of imide groups increases at ^{1780 cm -1} and 1720 cm ^-1. The reaction may be completed by lowering the temperature while confirming the target acid value, viscosity, molecular weight and the like. However, it is more preferable to continue the reaction until the isocyanate group disappears from the viewpoint of stability over time. Further, during or after the reaction, a catalyst, an antioxidant, a surfactant, another solvent or the like may be added as long as the physical properties of the resin to be synthesized are not impaired.

The acid value of the amideimide resin of the present invention is preferably 70 to 210 KOHmg / g, and particularly preferably 90 to 190 KOHmg / g. If it is 70 to 210 KOH mg / g, it exhibits excellent performance as a cured physical property.
Further, the amideimide resin of the present invention is preferably an amideimide resin that dissolves in the polar solvent containing neither nitrogen atom nor sulfur atom described above. Examples of such an amideimide resin include a branched amideimide resin having a branched structure and having an acid value of 60 KOHmg / g or more.

The (A) amidoimide resin in the curable resin composition has a number average molecular weight Mn of 500 to 1000, preferably in the range of 700 to 900.
In the present invention, when the number average molecular weight Mn of the (A) amidimide resin is 500 or more, the heat resistance of the cured coating film becomes good, and when the number average molecular weight Mn is 1000, the curable resin composition is developed. It is easy to add contrast when doing so, and the obtained cured coating film is also considered to have excellent resolution.
Unless otherwise specified, gel permeation chromatography (GPC) measurement results using a polystyrene standard are used for the number average molecular weight in the present invention.
The content of the amidimide resin (A) is preferably in the range of 30 to 85% by mass, particularly 40 to 70% by mass, based on the total solid content of the curable resin composition. This is because the Tg of the curable resin composition is improved and a cured coating film having excellent thermal characteristics can be obtained by setting the blending amount within this range.

[(B) Compound having an ethylenic double bond]
The curable resin composition of the present invention contains (B) a compound having an ethylenic double bond. (B) The compound having an ethylenic double bond can be photocured by irradiation with active energy rays to insolubilize the resin composition of the present invention in an alkaline aqueous solution or assist in insolubilization.

(B) As a specific example of the compound having an ethylenic double bond,
Monoacrylates having a hydroxyl group such as hydroxyalkyl acrylates such as 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate;
Diacrylates of glycols such as ethylene glycol, methoxytetraethylene glycol, polyethylene glycol and propylene glycol;
Acrylamides such as N, N-dimethylacrylamide, N-methylolacrylamide, N, N-dimethylaminopropylacrylamide;
Aminoalkyl acrylates such as N, N-dimethylaminoethyl acrylate, N, N-dimethylaminopropyl acrylate;
Alkyl diols such as hexanediol, nonanediol, and decanediol, polyvalent alcohols such as trimethylolpropane, pentaerythritol, dipentaerythritol, isocyanurate, and tris-hydroxyethyl isocyanurate, or ethireoxyside adducts and propylene oxide adducts thereof. Or polyvalent acrylates such as ε-caprolactone adducts, for example bifunctional acrylates such as 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, 1,10-decanediol diacrylate, trimethylolpropane. Triacrylate, pentaerythritol triacrylate, tris (2-hydroxyethyl) isocyanurate triacrylate, ethylene oxide-modified trimethylol triacrylate, ethylene oxide-modified trimethylolpropane triacrylate, propylene euside-modified trimethylolpropane triacrylate, ε-caprolactone Trifunctional acrylate such as modified tris- (2-acryloxyethyl) isocyanurate, tetrafunctional acrylate such as ditrimethylolpropane tetraacrylate, pentaerythritol tetraacrylate, ethoxylated pentaerythritol tetraacrylate, pentaacrylate such as dipentaerythritol 5 Hexological acrylates such as functional acrylates and dipentaerythritol hexaacrylates, phenoxy acrylates, bisphenol A diacrylates, and polyvalent acrylates such as ethylene oxide adducts or propylene oxide adducts of these phenols; glycerin diglycidyl ether, glycerin Polyvalent acrylates of glycidyl ethers such as triglycidyl ether, trimethylolpropane triglycidyl ether, triglycidyl isocyanurate; acrylates having a dicyclopentadiene skeleton such as dicyclopentadiene diacrylate; Examples thereof include acrylates and melamine acrylates in which polyols such as polycarbonate diols, hydroxyl group-terminated polybutadienes, and polyester polyols are directly acrylated or urethane acrylated via diisocyanates, and each methacrylate corresponding to the above acrylates.

Further, an epoxy (meth) acrylate resin obtained by reacting a polyfunctional epoxy resin such as cresol novolac type epoxy resin with (meth) acrylic acid, and a hydroxy acrylate such as pentaerythritol triacrylate on the hydroxyl group of the epoxy acrylate resin. Examples thereof include an epoxy urethane acrylate compound obtained by reacting a diisocyanate half urethane compound such as isophorone diisocyanate. Such an epoxy acrylate-based resin can improve the photocurability without lowering the dryness to the touch.
(B) As the compound having an ethylenically unsaturated group, one type may be used alone, or two or more types may be used in combination.
(B) The compound having an ethylenically unsaturated group is added at a ratio of preferably 0.1 to 25 parts by mass, more preferably 3 to 20 parts by mass, based on 100 parts by mass of the solid content of the curable resin composition. Will be done.
(B) The photocurability of the curable resin composition by setting the blending amount of the compound having an ethylenically unsaturated group to 0.1 part by mass or more with respect to 100 parts by mass of the solid content of the curable resin composition. By setting the content to 20 parts by mass or less, halation due to an excessive photopolymerization reaction can be prevented and good resolution can be obtained.

[(C) Photopolymerization Initiator]
The curable resin composition of the present invention contains (C) a photopolymerization initiator. As the photopolymerization initiator (C), a known and commonly used material can be used without particular limitation. In particular, as will be described later, it is represented by an oxime ester system containing a structure represented by the general formula (I), an α-aminoacetophenone system containing a structure represented by the general formula (II), and a general formula (III). An acylphosphine oxide system including a structure, a titanocene system having a structure represented by the general formula (IV), and the like can be used.
(C) As the photopolymerization initiator, one type may be used alone, or two or more types may be used in combination.

[Oxime ester-based photoinitiator]

オキシムエステル系光開始剤は上記一般式（Ｉ）で表され、一般式（Ｉ）、Ｒ１は、水素原子、フェニル基、アルキル基、シクロアルキル基、アルカノイル基またはベンゾイル基を表わす。Ｒ２は、フェニル基、アルキル基、シクロアルキル基、アルカノイル基またはベンゾイル基を表わす。Ｒ１およびＲ２により表されるフェニル基は、置換基を有していてもよく、置換基としては、例えば、炭素数１〜６のアルキル基、フェニル基、ハロゲン原子等が挙げられる。Ｒ１およびＲ２により表されるアルキル基としては、炭素数１〜２０のアルキル基が好ましく、アルキル鎖中に１個以上の酸素原子を含んでいてもよい。また、１個以上の水酸基で置換されていてもよい。Ｒ１およびＲ２により表されるシクロアルキル基としては、炭素数５〜８のシクロアルキル基が好ましい。Ｒ１およびＲ２により表されるアルカノイル基としては、炭素数２〜２０のアルカノイル基が好ましい。Ｒ１およびＲ２により表されるベンゾイル基は、置換基を有していてもよく、置換基としては、例えば、炭素数が１〜６のアルキル基、フェニル基等が挙げられる。

The oxime ester-based photoinitiator is represented by the above general formula (I), and the general formula (I) and R1 represent a hydrogen atom, a phenyl group, an alkyl group, a cycloalkyl group, an alkanoyl group or a benzoyl group. R2 represents a phenyl group, an alkyl group, a cycloalkyl group, an alkanoyl group or a benzoyl group. The phenyl group represented by R1 and R2 may have a substituent, and examples of the substituent include an alkyl group having 1 to 6 carbon atoms, a phenyl group, a halogen atom and the like. As the alkyl group represented by R1 and R2, an alkyl group having 1 to 20 carbon atoms is preferable, and one or more oxygen atoms may be contained in the alkyl chain. Further, it may be substituted with one or more hydroxyl groups. As the cycloalkyl group represented by R1 and R2, a cycloalkyl group having 5 to 8 carbon atoms is preferable. As the alkanoyl group represented by R1 and R2, an alkanoyl group having 2 to 20 carbon atoms is preferable. The benzoyl group represented by R1 and R2 may have a substituent, and examples of the substituent include an alkyl group having 1 to 6 carbon atoms, a phenyl group and the like.

Specific examples of the oxime ester-based photopolymerization initiator of the general formula (I) include 1,2-octanedione-1- [4- (phenylthio) -2- (O-benzoyloxime)], etanone, 1-[. 9-Ethyl-6- (2-methylbenzoyl) -9H-carbazole-3-yl]-, 1- (O-acetyloxime) and the like can be mentioned. Examples of commercially available products include CGI-325 manufactured by BASF Japan, Irgacure OXE01, Irgacure OXE02, N-1919 manufactured by ADEKA CORPORATION, NCI-831 and the like. A photopolymerization initiator having two oxime ester groups in the molecule and a photopolymerization initiator having a carbazole structure can also be preferably used.

[Α-Aminoacetophenone-based photoinitiator]

α−アミノアセトフェノン系光開始剤は上記一般式（ＩＩ）で表され、一般式（ＩＩ）中、Ｒ３およびＲ４は、各々独立に、炭素数１〜１２のアルキル基またはアリールアルキル基を表わし、Ｒ５およびＲ６は、各々独立に、水素原子、または炭素数１〜６のアルキル基を表わし、あるいは２つが結合して環状アル キルエーテル基を形成してもよい。

The α-aminoacetophenone-based photoinitiator is represented by the above general formula (II), and in the general formula (II), R3 and R4 each independently represent an alkyl group or an arylalkyl group having 1 to 12 carbon atoms. R5 and R6 each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, or the two may be bonded to form a cyclic alkyl ether group.

Specific examples of the α-aminoacetophenone-based photopolymerization initiator include (4-morpholinobenzoyl) -1-benzyl-1-dimethylaminopropane (Omnirad 369, trade name, manufactured by IGM Resins), 4- ( Methylthiobenzoyl) -1-methyl-1-morpholinoetan (Omnirad 907, trade name, manufactured by IGM Resins), 2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [ Commercially available compounds such as 4- (4-morpholinyl) phenyl] -1-butanone (Omnirad 379, trade name, manufactured by IGM Resins) or a solution thereof can be used.

[Acylphosphine oxide-based photoinitiator]

アシルホスフィンオキサイド系光開始剤は上記一般式（ＩＩＩ）で表され、一般式（ＩＩＩ）中、Ｒ７およびＲ８は、各々独立に、炭素数１〜１０のアルキル基、シクロペンチル基、シクロヘキシル基等の炭素数５〜８のシクロアルキル基、アリール基、またはハロゲン原子、アルキル基もしくはアルコキシ基で置換されたアリール基、または炭素数１〜２０のカルボニル基（但し、双方が炭素数１〜２０のカルボニル基である場合を除く。）を表わす。

The acylphosphine oxide-based photoinitiator is represented by the above general formula (III), and in the general formula (III), R7 and R8 are independently each of an alkyl group having 1 to 10 carbon atoms, a cyclopentyl group, a cyclohexyl group and the like. A cycloalkyl group having 5 to 8 carbon atoms, an aryl group, or an aryl group substituted with a halogen atom, an alkyl group or an alkoxy group, or a carbonyl group having 1 to 20 carbon atoms (provided that both are carbonyls having 1 to 20 carbon atoms). Except when it is a group.)

Specific examples of the acylphosphine oxide-based photopolymerization initiator include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, and bis (2,6-dimethoxybenzoyl). ) -2,4,4-trimethyl-Pentylphosphine oxide and the like. Examples of commercially available products include Omnirad TPO manufactured by IGM Resins and Omnirad 819 manufactured by IGM Resins.

[Titanocene photoinitiator]

チタノセン系光開始剤は上記一般式（ＩＶ）で表され、一般式（ＩＶ）中、Ｒ９およびＲ１０は、各々独立に、ハロゲン原子、アリール基、ハロゲン化アリール基、複素環含有ハロゲン化アリール基を表わす。

The titanosen-based photoinitiator is represented by the above general formula (IV), and in the general formula (IV), R9 and R10 are independently halogen atoms, aryl groups, aryl halide groups, and heterocyclic aryl halide groups. Represents.

Examples of the titanosen-based photopolymerization initiator include bis (η5-2,4-cyclopentadiene-1-yl) -bis (2,6-difluoro-3- (1H-pyrrole-1-yl) -phenyl) titanium. Be done. Examples of commercially available products include Irgacure 784 manufactured by BASF Japan Ltd.
In the present specification, the halogen or halogen atom means fluorine, chlorine, bromine, and iodine, and the aryl is a single-tube aromatic hydrocarbon such as a phenyl group and a polycyclic aromatic hydrocarbon group such as a naphthyl group. Means.

Other photopolymerization initiators used in the present invention include, for example, benzoin and benzoin alkyl ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether; 2-methylanthraquinone, 2-ethylanthraquinone, and the like. Anthraquinones such as 2-t-butylanthraquinone, 1-chloroanthraquinone and 2-amylanthraquinone; thioxanthones such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone and 2,4-diisopropylthioxanthone. Ketals such as acetphenone dimethyl ketal and benzyl dimethyl ketal; benzophenones such as benzophenone; xanthons; various peroxides such as 3,3'4,4'-tetra- (tert-butylperoxycarbonyl) benzophenone; 1 , 7-Bis (9-acrydinyl) heptane and the like.

In the curable resin composition of the present invention, in addition to the above photopolymerization initiator, N, N-dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, pentyl-4-dimethylaminobenzoate , Triethylamine, triethanolamine and other tertiary amines, and can be used in combination with one or more of known and commonly used photosensitizers. Further, when a deeper photocuring depth is required, a 3-substituted coumarin dye, a leuco dye or the like can be used in combination as a curing aid, if necessary.

The photopolymerization initiator (C) is generally added at a ratio of 0.1 to 50 parts by mass, more preferably 1 to 30 parts by mass, based on 100 parts by mass of the solid content of the curable resin composition. When the blending amount of the photopolymerization initiator (C) is within the above range with respect to 100 parts by mass of the solid content of the curable resin composition, the photocuring reaction is satisfactorily promoted.

[(D) Thermosetting resin]
The curable resin composition of the present invention may further contain (D) a thermosetting resin. Examples of the thermosetting resin include two or more cyclic ether groups and / or cyclic thioether groups, polyisocyanate compounds, blocked isocyanate compounds, etc. in molecules such as polyfunctional epoxy compounds, polyfunctional oxetane compounds, and episulfide resins. Known thermosetting compounds such as compounds having two or more isocyanate groups or blocked isocyanate groups in one molecule, amine resins such as melamine resin and benzoguanamine resin and derivatives thereof, bismaleimide, oxazine, cyclocarbonate compound, carbodiimide resin and the like. Sexual resin can be mentioned.

As the polyfunctional epoxy resin, a known and commonly used polyfunctional epoxy resin having at least two epoxy groups in one molecule can be used. The epoxy resin may be liquid or solid or semi-solid. The polyfunctional epoxy resin includes bisphenol A type epoxy resin; brominated epoxy resin; novolak type epoxy resin; bisphenol F type epoxy resin; hydrogenated bisphenol A type epoxy resin; glycidylamine type epoxy resin; hidden in type epoxy resin; oil ring. Formula epoxy resin; trihydroxyphenylmethane type epoxy resin; bixylenel type or biphenol type epoxy resin or a mixture thereof; bisphenol S type epoxy resin; bisphenol A novolac type epoxy resin; tetraphenylol ethane type epoxy resin; heterocyclic epoxy Resin; diglycidyl phthalate resin; tetraglycidyl xylenoyl ethane resin; naphthalene group-containing epoxy resin; epoxy resin having a dicyclopentadiene skeleton; glycidyl methacrylate copolymer epoxy resin; cyclohexyl maleimide and glycidyl methacrylate copolymer epoxy resin ; Epoxy-modified polybutadiene rubber derivative; CTBN-modified epoxy resin and the like, but are not limited thereto. As the epoxy resin, bisphenol A type or bisphenol F type novolak type epoxy resin, bixyleneol type epoxy resin, biphenol type epoxy resin, biphenol novolac type (biphenyl aralkyl type) epoxy resin, naphthalene type epoxy resin or a mixture thereof is preferable. ..

From the viewpoint of improving heat resistance, an epoxy resin having an aromatic ring skeleton (for example, a naphthalene skeleton) is preferable, and from the viewpoint of improving resolution, an epoxy resin having an alicyclic skeleton is preferable.

Examples of the epoxy resin having an aromatic ring skeleton include an epoxy resin having a naphthalene skeleton, particularly an aralkyl-type naphthalene. In the epoxy resin having a naphthalene skeleton, naphthalene has a planar structure, the coefficient of linear expansion can be lowered, and the heat resistance can be further improved. Commercially available epoxy resins having this naphthalene skeleton include, for example, ESN-190 and ESN-360 manufactured by Nippon Steel Chemical Corporation, EPICRON HP-4032, EPICRON, HP-4032D manufactured by DIC, and NC manufactured by Nippon Kayaku Corporation. -7000L can be mentioned. Further, examples of the epoxy resin having an alicyclic skeleton include an epoxy resin having a dicyclopentadiene skeleton. This epoxy resin having an alicyclic skeleton can be expected to have an effect of improving the glass transition temperature as compared with the epoxy resin having a chain skeleton.

As the thermosetting resin as described above, one type may be used alone, or two or more types may be used in combination.
When the thermosetting resin (D) is used, the blending amount is 5 to 20 parts by mass with respect to 100 parts by mass of the solid content of the curable resin composition so that the curable resin composition can be developed and cured. Both the heat resistance and the resolution of the object are considered to be extremely excellent.

[(E) Carboxyl group-containing resin]
In order to further improve the developability, the curable resin composition of the present invention may contain (E) a carboxyl group-containing resin as the case may be.
The (E) carboxyl group-containing resin is a compound having a structure different from that of the above-mentioned (A) amidimide resin, and uses a photosensitive or non-photosensitive resin that does not contain an amidimide structure and has a carboxyl group in the molecule. be able to. Specific examples thereof include the following (E1) to (E10).

Specific examples of the non-photosensitive carboxyl group-containing resin include the following compounds (either oligomer or polymer).
(E1) A carboxyl group-containing resin obtained by copolymerizing an unsaturated carboxylic acid such as (meth) acrylic acid with an unsaturated group-containing compound such as styrene, α-methylstyrene, lower alkyl (meth) acrylate, or isobutylene.

(E2) Diisocyanates such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates and aromatic diisocyanates, carboxyl group-containing dialcohol compounds such as dimethylolpropionic acid and dimethylolbutanoic acid, polycarbonate-based polyols and polyether-based compounds. Carboxyl group-containing urethane by multiple addition reaction with diol compounds such as polyols, polyester-based polyols, polyolefin-based polyols, acrylic-based polyols, phenolic hydroxyl groups containing bisphenol A-based alkylene oxide adduct diols and compounds having alcoholic hydroxyl groups. resin.

(E3) Aliphatic compounds such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates, and aromatic diisocyanates, and polycarbonate-based polyols, polyether-based polyols, polyester-based polyols, polyolefin-based polyols, acrylic-based polyols, and bisphenol A-based A terminal carboxyl group-containing urethane resin obtained by reacting an acid anhydride at the end of a urethane resin by a double addition reaction with a diol compound such as a compound having a phenolic hydroxyl group containing an alkylene oxide adduct diol and a compound having an alcoholic hydroxyl group.

(E4) Diisocyanate and bifunctional epoxy resin such as bisphenol A type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bixylenol type epoxy resin, biphenol type epoxy resin ( Meta) A carboxyl group-containing photosensitive urethane resin obtained by a double addition reaction with an acrylate or a modified partial acid anhydride thereof, a carboxyl group-containing dialcohol compound, and a diol compound.

(E5) During the synthesis of the resin (E2) or (E4) described above, a compound having one hydroxyl group and one or more (meth) acryloyl groups in a molecule such as hydroxyalkyl (meth) acrylate is added, and the terminal is added. (Meta) Acryloylated carboxyl group-containing photosensitive urethane resin.

(E6) During the synthesis of the resin (E2) or (E4) described above, one isocyanate group and one or more (meth) acryloyl groups in the molecule, such as isophorone diisocyanate and pentaerythritol triacrylate equimolar reactants. A carboxyl group-containing photosensitive urethane resin that has been acryloylated at the end (meth) by adding a compound having.

(E7) A (meth) acrylic acid is reacted with a bifunctional or higher polyfunctional epoxy resin as described later, and phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride and the like are added to the hydroxyl groups present in the side chains. A carboxyl group-containing photosensitive resin to which a basic acid anhydride is added. Here, the epoxy resin is preferably solid.

(E8) A (meth) acrylic acid was reacted with a polyfunctional epoxy resin obtained by further epoxidizing the hydroxyl groups of a bifunctional epoxy resin as described later with epichlorohydrin, and a dibasic acid anhydride was added to the generated hydroxyl groups. A photosensitive resin containing a carboxyl group. Here, the epoxy resin is preferably solid.

(E9) A cyclic ether such as ethylene oxide or a cyclic carbonate such as propylene carbonate is added to a polyfunctional phenol compound such as novolak, and the obtained hydroxyl group is partially esterified with (meth) acrylic acid, and many of the remaining hydroxyl groups are present. A carboxyl group-containing photosensitive resin obtained by reacting with a basic acid anhydride.

(E10) In addition to these resins (E1) to (E9), one epoxy group and one or more (meth) acryloyl groups are further added to the molecules such as glycidyl (meth) acrylate and α-methylglycidyl (meth) acrylate. A carboxyl group-containing photosensitive resin to which a compound is added.

(E11) Reaction formation of a polyalcohol resin or the like obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule, that is, a polyphenol compound (for example, phenol novolac or cresol novolac) with an alkylene oxide such as ethylene oxide or propylene oxide. A carboxyl group-containing photosensitive resin obtained by reacting a product with an unsaturated group-containing monocarboxylic acid such as (meth) acrylic acid, and further reacting the obtained reaction product with a polybasic acid anhydride.

(E12) Reaction obtained by reacting a reaction product obtained by reacting a polyphenol compound (for example, phenol novolac or cresol novolac) with a cyclic carbonate compound such as ethylene carbonate or propylene carbonate by reacting an unsaturated group-containing monocarboxylic acid. A carboxyl group-containing photosensitive resin obtained by reacting a product with a polybasic acid anhydride.
In the present invention, photosensitive carboxyl group-containing photosensitive resins having a polyphenol skeleton, such as those (E11) and (E12), are preferably used.

The carboxyl group-containing resin (E) may be used alone or in combination of two or more, but the total mass is 1 with respect to 100 parts by mass of the solid content of the (A) amidimide resin. It is preferably parts by mass or more and 40 parts by mass or less, which improves the developability of the curable resin composition and the resolution of the cured product.

[Inorganic filler]
The curable resin composition of the present invention can further contain an inorganic filler used in ordinary resin compositions.
Specifically, for example, silica, barium sulfate, calcium carbonate, silicon nitride, aluminum nitride, boron nitride, alumina, magnesium oxide, aluminum hydroxide, magnesium hydroxide, titanium oxide, mica, talc, Neuburg silica soil, organic bentonite. Non-metal fillers such as, and metal fillers such as copper, gold, silver, palladium, and silicon can be mentioned.
In the curable resin composition of the present invention, these inorganic fillers may be used alone or in combination of two or more. In the present invention, it is preferable to use barium sulfate, silica, or both.

The content of these inorganic fillers is 5 to 60% by mass, particularly preferably 10 to 50% by mass, based on the total solid content of the curable resin composition of the present invention. By appropriately selecting the blending amount according to the type of the inorganic filler, the strength can be improved without lowering the resolution of the cured coating film.

[Other ingredients]
In addition to the above-mentioned components, components other than the above-mentioned components can be added to the curable resin composition of the present invention as long as the effects of the present invention are not impaired. Additives include silicone-based and fluorine-based defoamers, leveling agents, thermosetting accelerators, thermal polymerization inhibitors, ultraviolet absorbers, solvents, silane coupling agents, plasticizers, foaming agents, flame retardants, and antistatic agents. Agents, antistatic agents, antibacterial / antifungal agents, etc. can be blended.

A solvent can be used to make the curable resin composition have an appropriate viscosity for coating on a substrate or a carrier film. Organic solvents are mainly used as such solvents, and specific examples thereof include ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, and the like. Petroleum-based solvents and the like can be mentioned. More specifically, ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol and propylene glycol monomethyl. Glycol ethers such as ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, triethylene glycol monoethyl ether; ethyl acetate, butyl acetate, dipropylene glycol methyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate , Esters such as propylene glycol butyl ether acetate; alcohols such as ethanol, propanol, ethylene glycol and propylene glycol; aliphatic hydrocarbons such as octane and decane; petroleum such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha and solvent naphtha It is a system solvent or the like. As such an organic solvent, one type may be used alone, or two or more types may be used in combination.

The curable resin composition of the present invention may be a liquid type or a dry film type obtained by drying the liquid type resin composition. The liquid type resin composition may be a two-component type or the like from the viewpoint of storage stability, but may be a one-component type. Hereinafter, the dry film will be described in detail as an embodiment of the curable resin composition.

[Manufacturing of dry film]
The dry film of the present invention has a resin layer obtained by applying the curable resin composition of the present invention on a film (hereinafter, also referred to as "carrier film") and then drying. In the dry film of the present invention, the curable resin composition of the present invention is diluted with an organic solvent to adjust the viscosity to an appropriate level, and a comma coater, a blade coater, a lip coater, a rod coater, a squeeze coater, a reverse coater, and a transfer coater are used. , A gravure coater, a spray coater or the like is applied onto a carrier film to a uniform thickness, and the film is usually obtained by drying at a temperature of 50 to 130 ° C. for 1 to 30 minutes. The coating film thickness is not particularly limited, but in general, the film thickness after drying may be appropriately set in the range of 3 to 100 μm, preferably 5 to 40 μm.

As the carrier film, a plastic film can be preferably used, and it is preferable to use a polyester film such as polyethylene terephthalate, a polyimide film, a polyamideimide film, a polypropylene film, and a plastic film such as a polystyrene film. The thickness of the carrier film is not particularly limited, but is generally selected as appropriate in the range of 10 to 150 μm.

After applying the curable resin composition of the present invention on the carrier film and drying it, a film that can be peeled off from the surface of the coating film for the purpose of preventing dust from adhering to the surface of the coating film (hereinafter, (Also referred to as “cover film”) may be laminated. As the peelable cover film, for example, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, a surface-treated paper or the like can be used, and when the cover film is peeled off, the adhesive strength between the coating film and the carrier film is increased. However, the adhesive strength between the coating film and the cover film may be smaller.

The drying treatment performed after applying the curable resin composition of the present invention on the carrier film is performed using a hot air circulation type drying furnace, an IR furnace, a hot plate, a convection oven, or the like, whereby a dry film can be obtained.

When the curable resin composition is applied directly onto a substrate, the substrate can be a pre-circuit-formed printed wiring board or flexible printed wiring board, as well as paper phenol, paper epoxy, glass cloth epoxy, glass polyimide, and glass. All grades using materials such as copper-clad laminates for high-frequency circuits using cloth / non-woven cloth epoxy, glass cloth / paper epoxy, synthetic fiber epoxy, fluorine / polyethylene / polyimideene ether, polyphenylene oxide / cyanate ester, etc. Examples thereof include copper-clad laminates (FR-4, etc.), other polyimide films, PET films, glass substrates, ceramic substrates, wafer plates, and the like.

[Manufacturing of cured product]
A cured product (cured film) using the curable resin composition of the present invention is produced as follows. That is, first, the curable resin composition is diluted with a solvent, if necessary, and then applied onto the substrate. The pattern formation on the curable resin composition is performed by selectively exposing (light irradiation) the resin layer obtained after volatile drying of the solvent and curing the exposed portion (light-irradiated portion). .. Then, the unexposed portion is developed with an alkaline aqueous solution (for example, 0.3 to 3% by mass sodium carbonate aqueous solution) to form a pattern of the coating film. Further, by irradiating the curable resin composition with light, a photocurable coating film is formed to form a cured coating film.

As the coating method, any method such as a dip coating method, a flow coating method, a bar coater method, and a screen printing method can be applied. Further, as the irradiation light source of the active energy ray, a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a xenon lamp, a metal halide lamp, or the like is suitable. In addition, UV-LED, laser beam, electron beam and the like can also be used as active energy rays.

Volatile drying performed after application is supported by a hot air circulation type drying oven, IR furnace, hot plate, convection oven, etc. It can be done by using the method of spraying on the body).

The cured resin composition or dry film after drying can be exposed to active energy rays by a contact method or a non-contact method through a photomask in which a pattern is formed. In addition, the exposed portion can be photocured by directly pattern-exposing the curable resin composition or the dry film with a laser direct exposure machine.

Here, as the exposure machine used for irradiating the active energy ray, any device equipped with a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a metal halide lamp, a mercury short arc lamp, etc., and capable of irradiating ultraviolet rays in the range of 350 to 450 nm. Further, for example, a direct drawing device such as a direct imaging device that directly draws an image with active energy rays from CAD data from a computer can also be used. As the light source of the direct drawing device, a mercury short arc lamp, an LED, or a gas laser or a solid-state laser may be used as long as a laser beam having a maximum wavelength in the range of 350 to 410 nm is used. The exposure amount for forming an image of the pattern resin layer varies depending on the film thickness and the like, but can be generally in the range of ^{20 to 1,500 mJ / cm 2} , preferably 20 to 1,200 mJ / cm 2.

As a developing method, a dipping method, a shower method, a spray method, a brush method, etc. can be adopted, and as a developing solution, potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, etc. can be adopted. , Ammonia, amines and other alkaline aqueous solutions can be used.

Furthermore the curable resin composition of the present invention can be an active energy ray, it is irradiated photocuring example in the range of ^{50mJ / cm 2 ~1500mJ / cm 2} . Light irradiation is performed by irradiation with active energy rays such as ultraviolet rays, electron beams, and chemical rays, preferably by ultraviolet irradiation. When the curable resin composition contains a thermosetting component, the curing of the coating film is promoted by heat-curing (post-curing) by heating to a temperature of about 100 to 180 ° C. after photocuring.

The curable resin composition of the present invention is applicable to electronic components. In the present invention, it means a component used for an electronic circuit, and includes active components such as a printed wiring board, a light emitting diode, and a laser diode, as well as passive components such as a resistor, a capacitor, an inductor, and a connector. The cured coating film of the sex composition exhibits the effect of the present invention. The curable resin composition of the present invention is particularly suitable for forming an insulating cured film of a printed wiring board, and is a permanent insulating film such as a coverlay, a solder resist, an interlayer insulating material, and an insulating material for forming a rewiring layer. It is more suitable for forming.

Since the electronic component containing the cured product obtained from the curable resin composition of the present invention is excellent in resolution and heat resistance of the cured product, it can fully exhibit its function as an electronic component. Further, since the cured product obtained from the curable resin composition of the present invention is also excellent in chemical resistance, a chemical used in cleaning with an acid or an alkali during the production of a substrate or with a solvent during mounting. As a result, the accuracy of electronic components can be maintained and improved without deterioration or deformation.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. The present invention is not limited to the following examples, and the "parts" and "%" described below are all based on mass unless otherwise specified.

[Synthesis of raw materials]
[Manufacturing of amidoimide resin]
Synthesis Example 1: Synthesis of (A) Amidoimide Resin 1 In a flask equipped with a stirrer, a thermometer, and a condenser, 5184 g of EDGA (diethylene glycol monoethyl ether acetate) and IPDI3N (isocyanurate-type triisocyanate synthesized from isophorone diisocyanate: NCO%). = 18.2) 2070 g (3 mol) and 1782 g (9 mol) of cyclohexane-1,3,4-tricarboxylic acid-3,4-anhydride were added, and the temperature was raised to 140 ° C. The reaction proceeded with foaming. The reaction was carried out at this temperature for 8 hours. The inside of the system became a pale yellow liquid, and as a result of measuring the characteristic absorption in the infrared spectrum, the characteristic absorption of isocyanate groups of 2270 cm-1 completely disappeared, and the absorption of imide groups was absorbed in 1780 cm-1 and 1720 cm-1. confirmed. The acid value was 140 KOHmg / g in terms of solid content, and the molecular weight was a number average molecular weight of 800 in terms of polystyrene. The concentration of the resin content was 40% by weight. The solution of this resin is referred to as the solution of (A) amidoimide resin 1.

Synthesis Example 2: Synthesis of (A') amidoimide resin 2 EDGA (diethylene glycol monoethyl ether acetate) 4628 g, IPDI3N (isocyanurate-type triisocyanate synthesized from isophorone diisocyanate: NCO) in a flask equipped with a stirrer, a thermometer, and a condenser. % = 18.2) 2070 g (3 mol) and 1386 g (7 mol) of cyclohexane-1,3,4-tricarboxylic acid-3,4-anhydride were added, and the temperature was raised to 140 ° C. The reaction proceeded with foaming. The reaction was carried out at this temperature for 8 hours. The inside of the system became a pale yellow liquid, and as a result of measuring the characteristic absorption in the infrared spectrum, the characteristic absorption of isocyanate groups of 2270 cm-1 completely disappeared, and the absorption of imide groups was absorbed in 1780 cm-1 and 1720 cm-1. confirmed. The acid value was 140 KOHmg / g in terms of solid content, and the molecular weight was a number average molecular weight of 5800 in terms of polystyrene. The concentration of the resin content was 40% by weight. The solution of this resin is a solution of (A') amidoimide resin 2.

Synthesis Example 3: Synthesis of (A') amidoimide resin 3 EDGA (diethylene glycol monoethyl ether acetate) 4903 g, IPDI3N (isocyanurate-type triisocyanate synthesized from isophorone diisocyanate: NCO) in a flask equipped with a stirrer, a thermometer, and a condenser. % = 18.2) 2070 g (3 mol) and 1683 g (8.5 mol) of cyclohexane-1,3,4-tricarboxylic acid-3,4-anhydride were added, and the temperature was raised to 140 ° C. The reaction proceeded with foaming. The reaction was carried out at this temperature for 8 hours. The inside of the system became a pale yellow liquid, and as a result of measuring the characteristic absorption in the infrared spectrum, the characteristic absorption of isocyanate groups of 2270 cm-1 completely disappeared, and the absorption of imide groups was absorbed in 1780 cm-1 and 1720 cm-1. confirmed. The acid value was 140 KOHmg / g in terms of solid content, and the molecular weight was a number average molecular weight of 1500 in terms of polystyrene. The concentration of the resin content was 40% by weight. A solution of this resin is a solution of (A') amidoimide resin 3.

Synthesis Example 4 (A) Synthesis of amidoimide resin 4 EDGA (diethylene glycol monoethyl ether acetate) 3554 g, IPDI3N (isocyanurate-type triisocyanate synthesized from isophorone diisocyanate: NCO% =) in a flask equipped with a stirrer, a thermometer, and a condenser. 18.2) 2070 g (3 mol) and 1333 g (9 mol) of 1,2,4-benzentricarboxylic acid 1,2-anhydride were added, and the temperature was raised to 140 ° C. The reaction proceeded with foaming. The reaction was carried out at this temperature for 8 hours. The inside of the system became a brown liquid, and as a result of measuring the characteristic absorption by infrared spectrum, the characteristic absorption of isocyanate groups of 2270 cm-1 completely disappeared, and the absorption of imide groups was confirmed at 1780 cm-1 and 1720 cm-1. Was done. The acid value was 140 KOHmg / g in terms of solid content, and the molecular weight was a number average molecular weight of 800 in terms of polystyrene. The concentration of the resin content was 40% by weight.
This resin solution is used as the amidoimide resin 4 solution.

The number average molecular weights of the amidimide resins 1 to 4 were measured by a gel permeation chromatography (GPC) method (polystyrene standard) using the following measuring device and measuring conditions.

Device name: Waters 2695, manufactured by Waters
Detector: Waters, 2414 Differential Refractometer (RI) Detector Column: Waters, HSPgel Column for High Speed Analysis, HR MB-L,
3 μm, 6 mm × 150 mm × 2, and
Waters, HSPgel column, HR 1,3 μm,
6 mm x 150 mm x 2
Measurement condition:
Column temperature: 40 ° C
RI detector set temperature: 35 ° C
Developing solvent: Tetrahydrofuran Flow rate: 0.5 ml / min Sample volume: 10 μl
Sample concentration: 0.5 wt%

Synthesis Example 5: Synthesis of carboxyl group-containing resin A novolak type cresol resin (manufactured by Showa High Polymer Co., Ltd., trade name "Shonol CRG951") is added to an autoclave equipped with a thermometer, a nitrogen introduction device and an alkylene oxide introduction device, and a stirring device. , OH equivalent: 119.4) 119.4 g, potassium hydroxide 1.19 g and toluene 119.4 g were charged, the inside of the system was replaced with nitrogen while stirring, and the temperature was raised by heating. Next, 63.8 g of propylene oxide was gradually added dropwise, and the mixture was reacted at 125 to 132 ° C. and 0 to 4.8 kg / cm2 for 16 hours. Then, the mixture was cooled to room temperature, and 1.56 g of 89% phosphoric acid was added to and mixed with this reaction solution to neutralize potassium hydroxide, and the non-volatile content was 62.1% and the hydroxyl value was 182.2 g / eq. A propylene oxide reaction solution of the novolak type cresol resin was obtained. This had an average of 1.08 mol of alkylene oxide added per equivalent of phenolic hydroxyl group. 293.0 g of the alkylene oxide reaction solution of the obtained novolak type cresol resin, 43.2 g of acrylic acid, 11.53 g of methanesulfonic acid, 0.18 g of methylhydroquinone and 252.9 g of toluene were added to a stirrer, a thermometer and an air blowing tube. The reactor was charged with, and air was blown at a rate of 10 ml / min, and the reaction was carried out at 110 ° C. for 12 hours with stirring. As for the water produced by the reaction, 12.6 g of water was distilled off as an azeotropic mixture with toluene. Then, the mixture was cooled to room temperature, the obtained reaction solution was neutralized with 35.35 g of a 15% aqueous sodium hydroxide solution, and then washed with water. Then, toluene was distilled off while substituting 118.1 g of diethylene glycol monoethyl ether acetate with an evaporator to obtain a novolak type acrylate resin solution. Next, 332.5 g of the obtained novolak-type acrylate resin solution and 1.22 g of triphenylphosphine were charged into a reactor equipped with a stirrer, a thermometer and an air blowing tube, and air was blown at a rate of 10 ml / min. With stirring, 60.8 g of tetrahydrophthalic anhydride was gradually added, and the mixture was reacted at 95 to 101 ° C. for 6 hours. A carboxyl group-containing resin having an acid value of 88 mgKOH / g and a solid content of 71% was obtained.

[Examples 1 to 5 and Comparative Examples 1 to 3]
[Preparation of curable resin composition]
As shown in Table 1, each component was blended, premixed with a stirrer, and then kneaded and dispersed by a three-roll mill to prepare a curable resin composition according to Examples and Comparative Examples.
The blending amount in the table indicates the mass part (in terms of solid content).

<Optimal exposure>
For the curable resin compositions of the above Examples and Comparative Examples, a circuit pattern substrate having a copper thickness of 35 μm was bafflor-polished, washed with water, dried, and then applied to the entire surface of the circuit pattern substrate by a screen printing method. Dry for 60 minutes in a hot air circulation type drying furnace at ° C. After drying, exposure is performed via a step tablet (Kodak No. 2) using a projection type exposure device equipped with a high-pressure mercury lamp, and development (30 ° C., 0.2 MPa, 1 mass% sodium carbonate aqueous solution) is performed in 60 seconds. The optimum exposure amount was set when the pattern of the step tablet remaining at the time was 7 steps.

<1. Resolution>
The curable resin composition was diluted with methyl ethyl ketone to an appropriate viscosity and applied onto a carrier film (polyethylene terephthalate film). This was heated and dried in a hot air dryer at 80 ° C. for 30 minutes to form a curable resin composition layer having a thickness of 20 μm, and a cover film (polypropylene film) was laminated on the coating film to obtain a dry film. After that, the cover film was peeled off, the obtained dry film was heat-laminated on a copper-clad laminated substrate, and pattern exposure was performed at an optimum exposure amount using a projection exposure apparatus equipped with a high-pressure mercury lamp, and a 1% Na2CO3 aqueous solution at 30 ° C. was used. Was developed for 250 seconds under the condition of a spray pressure of 0.2 MPa to form a via pattern. This substrate was irradiated with ultraviolet rays in a UV conveyor furnace under the condition of an integrated exposure of 1000 mJ / cm ² , and then heated at 180 ° C. for 60 minutes to be cured.
The resolution of the substrate prepared by the evaluation substrate preparation method as described above was observed using an electron microscope. The via opening size was confirmed and evaluated as follows.
⊚: Via pattern formation of φ20 μm or less 〇: Via pattern shape of φ20 μm or more and less than 50 μm Δ: Via pattern shape of φ50 μm or more ×: Opening shape cannot be formed

<2. Developability>
The curable resin composition was diluted with methyl ethyl ketone to an appropriate viscosity and applied onto a carrier film (polyethylene terephthalate film). This was heated and dried in a hot air dryer at 80 ° C. for 30 minutes to form a curable resin composition layer having a thickness of 20 μm, and a cover film was laminated on the obtained coating film to obtain a dry film. Then, the cover film was peeled off, and the obtained dry film was heat-laminated on the copper-clad laminated substrate. The obtained substrate was developed with a 1% Na2CO3 aqueous solution at 30 ° C. under the condition of a spray pressure of 0.2 MPa for 60 seconds, and the development residue was evaluated as follows.
⊚: No residue 〇: Residue with a film thickness of less than 1 μm
Δ: Residue with a film thickness of 1 μm or more and less than 3 μm ×: Residue with a film thickness of 3 μm or more

<3. Heat resistance>
The curable resin composition was diluted with methyl ethyl ketone to an appropriate viscosity and applied onto a carrier film. This was heated and dried in a hot air dryer at 80 ° C. for 30 minutes to form a curable resin composition layer having a thickness of 20 μm, and a cover film was laminated on the coating film to obtain a dry film. After that, the cover film was peeled off, heat-laminated on the copper foil, solid-exposed at the optimum exposure amount using a projection exposure apparatus equipped with a high-pressure mercury lamp, and a 1% Na2CO3 aqueous solution at 30 ° C. was sprayed under the condition of 0.2 MPa. Development was carried out for 250 seconds. This substrate was irradiated with ultraviolet rays in a UV conveyor furnace under the condition of an integrated exposure of 1000 mJ / cm ² , and then heated at 180 ° C. for 60 minutes to be cured. A cured coating film was obtained by peeling off the cured coating film from the obtained copper foil with a cured coating film.
The glass transition temperature of the obtained cured coating film was measured under the following conditions.
Device: Dynamic viscoelasticity measuring device (DMA6100 manufactured by Seiko Instruments)
Measurement temperature: 30-300 ° C (5 ° C / min)
Frequency: 1Hz
Glass transition temperature: The maximum value of tan δ measured is taken as the glass transition temperature.
It is judged that the higher the glass transition temperature, the higher the heat resistance because the elastic change occurs at a higher temperature.
The evaluation criteria are as follows.
⊚: 190 ° C or higher 〇: 180 ° C or higher Δ: 170 ° C or higher ×: less than 170 ° C

<4. Breaking strength>
The evaluation substrate used for the heat resistance evaluation was evaluated by measuring the breaking strength in accordance with JIS K7127. The evaluation criteria are as follows.
⊚: 80 MPa or more 〇: 40 MPa or more, less than 80 MPa Δ: less than 40 MPa

<5. Chemical resistance>
The curable resin composition is diluted with methyl ethyl ketone to an appropriate viscosity, coated on a silicon wafer using a spin coater, and heated and dried in a hot air dryer at 80 ° C. for 30 minutes to obtain a curable resin composition layer having a thickness of 20 μm. Formed. A solid exposure was carried out at an optimum exposure amount using a projection type exposure apparatus equipped with a high-pressure mercury lamp, and a 1% Na2CO3 aqueous solution at 30 ° C. was developed under the condition of a spray pressure of 0.2 MPa for 250 seconds.
This substrate was irradiated with ultraviolet rays in a UV conveyor furnace under the condition of an integrated exposure of 1000 mJ / cm ² , and then heated at 180 ° C. for 60 minutes to be cured. The curable resin composition layer on the obtained wafer was cross-cut using a cutter so as to form 100 square squares having a side of 1 mm. A 10% potassium hydroxide solution was heated to 40 ° C in a water bath, soaked in a cross-cut wafer with a resin layer for 30 minutes, washed with water, and a cellophane tape (registered trademark) was attached to the dried resin layer to withstand peeling. The chemical properties were evaluated. The evaluation criteria are as follows.
◯: No peeling △: The resin layer slightly peels off from the wafer along the cross-cut line ×: One or more cross-cut square squares peel off

＊表中の配合量は質量部を基準とする。

* The blending amount in the table is based on the mass part.

Details of the materials listed in the table are shown below.
Amidimide resin 1: Synthesized according to Synthesis Example 1 Mn = 800
Amidimide resin 2: Synthesized according to Synthesis Example 2 Mn = 5800
Amidimide resin 3: Synthesized according to Synthesis Example 3 Mn = 1500
Amidimide resin 4: Synthesized according to Synthesis Example 4 Mn = 800
Photopolymerization initiator 1: 2-Methyl-1- (4-methylophenyl) -2-morpholinopropane-1-one Resin having an ethylenic double bond 1: Dipentaerythritol hexaacrylate has an ethylenic double bond Resin 2: Ethylene oxide-modified trimethylol propantriacrylate carboxyl group-containing resin: Synthesis Example 5
Thermosetting resin: Naftor-modified epoxy resin NC-7000L (manufactured by Nippon Kayaku Co., Ltd.)
Inorganic particles 1: Barium sulfate Inorganic particles 2: Silica

From the above, it can be seen that the curable resin composition of the present invention is not only excellent in heat resistance, but also has improved resolution, developability, breaking strength, and chemical resistance.

The present invention is not limited to the configuration and examples of the above-described embodiment, and various modifications can be made within the scope of the gist of the invention.

Claims (6)

(A) Amidoimide resin and
(B) A compound having an ethylenic double bond and
(C) Photopolymerization initiator and
Including
The amidimide resin (A) is a reaction product of an isocyanurate-type polyisocyanate synthesized from an isocyanate having an aliphatic structure and a tricarboxylic acid anhydride, and is characterized by having a number average molecular weight of 500 to 1000. Curable resin composition. The curable resin composition according to claim 1, wherein the tricarboxylic acid anhydride has an aliphatic structure. The curable resin composition according to claim 1 or 2, further comprising (D) a thermosetting resin. A dry film comprising a resin layer composed of the curable resin composition according to any one of claims 1 to 3. A cured product obtained by curing the resin layer of the curable resin composition according to any one of claims 1 to 3 or the dry film according to claim 4. An electronic component containing the cured product according to claim 5.