JP2013137373A - Photosensitive resin composition and cured product of the same, and production method of photosensitive resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive resin composition excellent in photosensitivity, which allows formation of a fine pattern and gives a cured coating film that is excellent in flexibility, insulating property, adhesion property and the like and is to be suitably used for a photo-solder resist.SOLUTION: The photosensitive resin composition includes a carboxyl group-containing photosensitive ester resin (A), at least one compound (B) selected from an epoxy group-containing compound, a non-blocked isocyanate compound or the like, and a photopolymerization initiator (C). The resin (A) is a compound obtained through steps of: producing a half ester compound (c) by reacting a polyol compound (a) with a tetrabasic acid dianhydride (b); generating a hydroxyl-group containing photosensitive ester resin (e) by reacting the half ester compound (c) with a compound (d) having an epoxy group or an oxetane group, and an ethylenically unsaturated group; and then reacting the hydroxyl group-containing photosensitive ester resin (e) with a dibasic acid anhydride (f).

Description

  The present invention relates to a photosensitive resin composition containing a photosensitive resin useful for printed wiring boards and the like, a cured product thereof, and a method for producing the photosensitive resin. More specifically, it is useful as a solder resist for flexible printed wiring boards, plating resists, interlayer electrical insulation materials for multilayer printed wiring boards, photosensitive optical waveguides, etc., and has excellent developability, and its cured film has adhesiveness and flexibility. The present invention relates to a photosensitive resin composition containing a specific photosensitive resin that gives a cured product excellent in solder heat resistance, chemical resistance, electrical insulation, and the like, and a cured product thereof, and a method for producing the photosensitive resin. Furthermore, the present invention relates to a highly flame-retardant photosensitive solder resist ink and a dry film type photosensitive solder resist containing the photosensitive resin composition.

  In the soldering process that is performed when protecting the wiring (circuit) pattern formed on the board from the external environment or when mounting electronic components on the printed wiring board, solder does not adhere to unnecessary parts. In order to protect the printed wiring board, a protective layer called a coverlay or a solder mask is coated on the printed wiring board. Until now, since hard printed wiring boards have been the mainstream, the resist coating after curing mainly requires adhesion to the substrate and heat resistance in addition to pattern accuracy. However, in recent years, the use of flexible printed wiring boards has greatly increased, and a protective layer used for a wiring pattern formed on a polyimide film is required to have adhesion with polyimide, flexibility, and electrical insulation.

 Conventionally, as a protective layer for flexible printed wiring boards, a polyimide film called a coverlay film is made by punching a mold that matches the pattern and then pasted using an adhesive, or by thermosetting applied by screen printing There are various types of inks, but for high density and high definition accompanying recent advances in electronics, UV curable photoresist type solder resist ink or dry film type solder resist that can be patterned with higher precision is available. It is being considered.

  Generally, in the photo solder resist for a flexible printed wiring board, the photo solder resist conventionally used for a rigid substrate can obtain pattern accuracy, but the cured coating film is hard, and the base of the flexible printed wiring board. There was a problem that adhesiveness with polyimide as a material was poor, and sufficient flexibility, flexibility and folding resistance could not be obtained.

 In recent years, many proposals have been made as photo solder resists having flexibility. For example, a resist ink composition is disclosed that includes a resin obtained by reacting succinic anhydride with an addition product of an epoxy resin having a bisphenol A skeleton in the main chain and an unsaturated group-containing monocarboxylic acid (Patent Document 1). ). Although this is excellent in developability, photosensitivity, adhesion, heat resistance, etc., there is a problem that the flexibility and folding resistance are still insufficient. In addition, as a photosensitive thermosetting composition, a reaction product of a secondary hydroxyl group generated by an esterification reaction of a cresol novolak type epoxy compound and an unsaturated monocarboxylic acid, and a saturated or unsaturated polybasic acid anhydride, A reaction product of the secondary hydroxyl group and an unsaturated group-containing isocyanate compound has been proposed (Patent Document 2). Although these are extremely excellent in adhesion, solder heat resistance, and coating film resistance, there is still a problem that the flexibility and folding resistance are insufficient.

 There has also been proposed a photosensitive element containing a polymer obtained by copolymerizing a monomer containing (meth) acrylic acid and (meth) acrylic acid ester as a binder component (Patent Document 3). These are excellent in developability and resolution, but when used in flexible printed wiring board applications, sufficient adhesion / flexibility / bending resistance to the polyimide substrate cannot be obtained.

 Moreover, the photosensitive resin composition which added the phosphorus-type flame retardant is disclosed (patent document 4). In order to reduce the burden on the environment, these are made flame retardant by using a non-halogen flame retardant. However, in order to give sufficient flame retardancy with a non-halogen flame retardant, it is necessary to add a large amount of flame retardant, and because of this, the resolution in the order of several tens of μm, which has been demanded in recent years, is required. Since the physical properties other than the flame retardancy required for the resist are lowered, such as a significant decrease, it is not sufficient to achieve both the flame retardancy and other physical properties.

 In addition, similar to the photosensitive resin of the present invention, compounds having an ester bond derived from half esterification in the main chain are also disclosed (Patent Documents 5 and 6). In Patent Document 5, a polyisocyanate compound is reacted with a terminal hydroxyl group-containing compound obtained from a polyol compound and a tetrabasic acid dianhydride, and a (meth) acrylate having one epoxy group in the molecule is further reacted. The resulting carboxyl group-containing urethane resin has been proposed. Although these have sufficient flexibility, they have a urethane bond in the main chain, so they are chemically unstable, such as being susceptible to cleavage under high temperature conditions. However, the various coating film resistances were not sufficient.

 Patent Document 6 discloses that a diepoxy compound is added to a terminal carboxyl group-containing compound obtained from a compound having at least one unsaturated double bond and one alcoholic hydroxyl group and tetrabasic acid dianhydride in one molecule. A carboxyl group-containing ester resin obtained by polyaddition and further addition of a polybasic acid anhydride has been proposed. This is excellent in solder heat resistance, chemical resistance, etc., but since the main chain does not have a structure derived from polyol or urethane bond, a satisfactory flexibility cannot be obtained.

 In this way, the conventional technology achieves both sufficient flexibility and folding resistance required as a protective layer for flexible printed wiring boards, and developability and solder heat resistance that can realize highly accurate patterning, and circuit A resin composition that can satisfy all physical properties necessary for the protective layer, such as electrical insulation, chemical resistance, and flame retardancy, and a cured product thereof have not been obtained.

Printed wiring boards are required to have high precision and high density in order to reduce the size and weight of portable devices and improve communication speed. Flexible printed wiring used mainly in the bent and connected areas of devices. The trend is the same for boards. Against this background, demands for protective layers for flexible printed wiring boards are becoming more and more advanced, and developability that can achieve higher definition of resist patterns and higher flexibility than conventional requirements. -While maintaining folding resistance, performance that satisfies solder heat resistance, substrate adhesion, high insulation, coating film resistance, flame resistance, etc. is required. Currently, commercially available photo solder resists cannot sufficiently meet these requirements.
Japanese Patent No. 3281473 Japanese Patent No. 2707495 JP 2004-279479 A JP 2006-251715 A JP 2001-159815 A Japanese Patent No. 4533591

  The present invention has excellent photosensitivity to active energy rays, and can form a fine pattern by developing with a dilute alkaline aqueous solution. The cured coating film obtained through a post-curing (post-cure) process is flexible, insulating, and adhesive. An object of the present invention is to provide a photosensitive resin composition that is excellent in solder heat resistance, coating film resistance, flame retardancy, etc., and that is suitably used for a photo solder resist, and a cured product thereof, as well as a method for producing a photosensitive resin. And

  As a result of intensive studies, the present inventors have found that a photosensitive resin composition containing a specific carboxyl group-containing photosensitive ester resin (A) solves the above-described problems. The present invention has been completed.

That is, the present invention relates to a compound (B) that is at least one selected from a carboxyl group-containing photosensitive ester resin (A), an epoxy group-containing compound, an unblocked isocyanate compound, and a blocked isocyanate compound, and a photopolymerization initiator (C A photosensitive resin composition comprising:
The carboxyl group-containing photosensitive ester resin (A) is
A polyol compound (a) and a tetrabasic acid dianhydride (b) are reacted to produce a half ester compound (c);
Reacting the half ester compound (c) with a compound (d) having an epoxy group or oxetane group and an ethylenically unsaturated group to produce a hydroxyl group-containing photosensitive ester resin (e);
The present invention relates to a photosensitive resin composition obtained by reacting the hydroxyl group-containing photosensitive ester resin (e) with a dibasic acid anhydride (f).

  Moreover, this invention relates to the said photosensitive resin composition which contains the thermosetting adjuvant (D) of an amino resin, a phenol resin, a polycarbodiimide compound, an aziridine compound, a benzoxazine compound, and a maleimide compound further.

Moreover, this invention relates to the said photosensitive resin composition whose acid value of carboxyl group-containing photosensitive ester resin (A) is 10-200 mgKOH / g.
Moreover, this invention relates to the said photosensitive resin composition whose ethylenically unsaturated group equivalent of carboxyl group-containing photosensitive ester resin (A) is 200-3000 g / eq.

Moreover, this invention relates to the said photosensitive resin composition whose weight average molecular weights of carboxyl group-containing photosensitive ester resin (A) are 3000-100000.
Moreover, this invention relates to the hardened | cured material formed by hardening | curing the said photosensitive resin composition.
Moreover, this invention relates to the photosensitive soldering resist ink containing the said photosensitive resin composition and a flame retardant.

The present invention also provides
A first step of reacting the polyol compound (a) with the tetrabasic acid dianhydride (b) to obtain a half ester compound (c);
A second step of obtaining a hydroxyl group-containing photosensitive ester resin (e) by reacting the half ester compound (c) with a compound (d) having an epoxy group or oxetane group and an ethylenically unsaturated group;
A third step of obtaining a carboxyl group-containing photosensitive ester resin (A) by reacting the hydroxyl group-containing photosensitive ester resin (e) with a dibasic acid anhydride (f);
The present invention relates to a method for producing a carboxyl group-containing photosensitive ester resin.

  According to the present invention, it has excellent photosensitivity to active energy rays, and can form a fine pattern by developing with a dilute aqueous alkali solution. It is excellent in solder heat resistance, coating film resistance, flame retardancy, etc., and can provide a photosensitive resin composition suitably used for a photo solder resist and a cured product thereof, and further a method for producing a photosensitive resin. I can do it now. The photosensitive resin composition of the present invention includes a solder resist for flexible printed wiring boards, a photosensitive coverlay film, a plating resist, an interlayer electrical insulating material for wiring boards, a photosensitive optical waveguide, and a silver paste on a polyethylene terephthalate film. It can be suitably used as a coverlay resist for a flexible printed circuit board formed with a circuit by printing a conductive ink such as carbon paste.

  In the photosensitive resin composition of the present invention, since the carboxyl group-containing photosensitive ester resin (A) does not have a urethane bond derived from the reaction of an isocyanate group and a hydroxyl group in the main chain, the main chain is chemically stable. Therefore, the resulting cured coating film has excellent resistance to various coating films, exhibits excellent heat resistance even when exposed to high temperature conditions such as a solder bath, and exhibits excellent electrical insulation even under high temperature and high humidity. To do. Furthermore, since the carboxyl group-containing photosensitive ester resin (A) of the present invention has a photosensitive group and a carboxyl group in the side chain, even if the amount of the photosensitive group and carboxyl group contained is small, Excellent resolution and developability. The functional groups introduced into these side chains can be arbitrarily adjusted in the amount introduced compared to the case where they are introduced only at the ends of the main chain, so that they have excellent photocurability, developability, resolution and coating film resistance. It can be demonstrated. Hereinafter, the carboxyl group-containing photosensitive ester resin (A) and the photosensitive resin composition of the present invention will be described.

  In the carboxyl group-containing photosensitive ester resin (A) of the present invention, as a first step, a polyol compound (a) is reacted with a tetrabasic acid dianhydride (b) to form a half ester compound (c). To do. Next, as a second step, the half-ester compound (c) is reacted with a compound (d) having an epoxy group or oxetane group and an ethylenically unsaturated group to react a hydroxyl group-containing photosensitive ester resin (e). Is made. Furthermore, it can obtain by making the said hydroxyl group containing photosensitive ester resin (e) and dibasic acid anhydride (f) react as a 3rd process. Hereinafter, the manufacturing method of carboxyl group-containing photosensitive ester resin (A) is demonstrated in detail.

  First, the half ester compound (c) obtained at the 1st process of this invention is demonstrated. The half ester compound (c) can be obtained by reacting the polyol compound (a) with the tetrabasic acid dianhydride (b). The hydroxyl group in the polyol compound (a) and the tetrabasic acid diacid are obtained. It is preferable that the acid anhydride group in the anhydride (b) is reacted at a molar ratio of hydroxyl group / acid anhydride group = 2/1 to 1/2. If the molar ratio is out of the range, the molecular weight of the finally obtained carboxyl group-containing photosensitive ester resin (A) becomes low, and it becomes difficult to obtain desired coating film resistance and film formability.

  In addition, the molar ratio as used in the field of this invention is a molar ratio with which functional groups actually react, and various starting materials use the quantity which enables reaction by the said molar ratio. Therefore, for example, when each starting material is charged in the reaction of “polyol compound (a)” with “tetrabasic acid dianhydride (b)”, 1.0 mol of hydroxyl group in “polyol compound (a)” In contrast, the acid anhydride group in the “tetrabasic acid dianhydride (b)” may be charged in an amount exceeding 2.0 mol (preferably charged at an upper limit of 2.1 mol).

  The polyol compound (a) used in the present invention has two or more hydroxyl groups, and further has a repeating unit having a polymerization degree of 2 or more in its structure. In addition, as the polyol compound (a), a compound containing two hydroxyl groups is preferably used, and the weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (hereinafter also referred to as “GPC”) is preferably 500 to 50,000. It is a compound of this. Examples of the polyol compound (a) include polyester polyols, polycarbonate polyols, polyether polyols, polybutadiene polyols, and polysiloxane polyols. In the present application, unless otherwise specified, the weight average molecular weight means a polystyrene-reduced weight average molecular weight by GPC measurement.

  Examples of the polyester polyol used in the present invention include a polyester polyol obtained by condensation reaction of a polyfunctional alcohol component and a dibasic acid component. Among the polyfunctional alcohol components, diols include ethylene glycol, propylene glycol, dipropylene glycol, diethylene glycol, triethylene glycol, butylene glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 3,3 '-Dimethylol heptane, polyoxyethylene glycol, polyoxypropylene glycol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, octanediol, butylethylpentanediol, 2-ethyl-1,3- Hexanediol, cyclohexanediol, bisphenol A and the like, and as the polyfunctional alcohol component having three or more hydroxyl groups, trimethylolethane, polytrimethylolethane, trimethylol group Bread, poly trimethylol propane, pentaerythritol, poly pentaerythritol, sorbitol, mannitol, arabitol, xylitol, galactitol, glycerol and the like.

  Examples of the dibasic acid component include aliphatic or aromatic dibasic acids such as terephthalic acid, adipic acid, azelaic acid, sebacic acid, phthalic anhydride, isophthalic acid, trimellitic acid, and anhydrides thereof.

  Β-butyrolactone, β-propiolactone, γ-butyrolactone, γ-valerolactone, δ-valerolactone, ε-caprolactone, γ-caprolactone, γ-heptanolactone, α-methyl-β-propiolactone, etc. Polyester polyols obtained by ring-opening polymerization of cyclic ester compounds such as lactones can also be used.

  Polyester polyols having phosphorus atoms can also be used, specifically, 2- (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-yl) methyl succinic acid or its acid anhydride; A polycondensate with ethylene glycol, or 2- (9,10-dihydro-9-oxa-10-oxide-10-phosphaphenanthrene-10-yl) methylsuccinic acid-bis- (2-hydroxyethyl) -ester, Or the polyester polyol obtained by the polycondensation is mentioned.

  Specifically in the polyester polyol, Kuraray polyol P series of Kuraray Co., Ltd. can be used. Among these, P-1041, P-2041, P-2010, P-2020, P-1030, and P-2030 are preferable because they have insulation reliability and heat resistance.

  The polycarbonate polyol used in the present invention has a structure represented by the following general formula (1) in its molecule.

General formula (1)
− [— O—R ⁸ —O—CO—] _m —
(In the formula, R ⁸ represents a divalent organic residue, and m represents an integer of 1 or more.)

  The polycarbonate polyol can be obtained, for example, by (1) a reaction between glycol or bisphenol and a carbonate ester, or (2) a reaction in which phosgene is allowed to act on glycol or bisphenol in the presence of an alkali.

Specific examples of the carbonic acid ester used in the production method (1) include dimethyl carbonate, diethyl carbonate, diphenyl carbonate, ethylene carbonate, and propylene carbonate.

Specific examples of glycols or bisphenols used in the production methods (1) and (2) include ethylene glycol, propylene glycol, dipropylene glycol, diethylene glycol, triethylene glycol, butylene glycol, and 3-methyl-1,5-pentanediol. 2-methyl-1,8-octanediol, 3,3′-dimethylolheptane, polyoxyethylene glycol, polyoxypropylene glycol, propanediol, 1,3-butanediol, 1,4-butanediol, 1, 5-pentanediol, 1,6-hexanediol, 1,9-nonanediol, neopentyl glycol, octanediol, butylethylpentanediol, 2-ethyl-1,3-hexanediol, cyclohexanediol It can be used bisphenols such as bisphenol A, bisphenol F, ethylene oxide to the bisphenols, also bisphenols obtained by adding an alkylene oxide such as propylene oxide. These compounds can be used as one kind or a mixture of two or more kinds.

  Specifically, the Kuraray polyol C series of Kuraray Co., Ltd. can be used in the polycarbonate polyol. Among these, PMHC-1050, PMHC-2050, C-1090, C-2090, C-1065N, C-2065N, C-1015N, and C-2015N are preferable because of their flexibility.

Examples of the polyether polyol used in the present invention include polymers, copolymers, and graft copolymers of alkylene oxides such as tetrahydrofuran, ethylene oxide, propylene oxide, and butylene oxide;
Polyether polyols obtained by condensation of hexanediol, methylhexanediol, heptanediol, octanediol or mixtures thereof;
Aromatic diols such as bisphenols obtained by adding alkylene oxides such as ethylene oxide and propylene oxide to bisphenol A and bisphenol F;
Using polyhydric alcohols such as trimethylol ethane, polytrimethylol ethane, trimethylol propane, polytrimethylol propane, pentaerythritol, polypentaerythritol, sorbitol, mannitol, arabitol, xylitol, galactitol, glycerin as part of the raw material Synthesized polyethylene oxide, polypropylene oxide, block copolymer or random copolymer of ethylene oxide / propylene oxide, polytetramethylene glycol, block copolymer or random copolymer of tetramethylene glycol and neopentyl glycol, etc. Polyether polyols;
Those having two or more hydroxyl groups can be used.

  The polybutadiene polyols used in the present invention include, for example, those obtained by hydrogenating unsaturated bonds in the molecule, such as polyethylene polyols, polypropylene polyols, polybutadiene polyols, hydrogenated polybutadiene polyols, polyisoprene polyols, hydrogenated compounds. And polyisoprene polyol.

  Commercially available products of polybutadiene polyol include NISSSO PB (G series) from Nippon Soda Co., Ltd., liquid polybutadiene having hydroxyl groups at both ends, such as Poly-Pd from Idemitsu Petrochemical Co., Ltd .; NISSSO PB (GI series) from Nippon Soda Co., Ltd. ), Hydrogenated polybutadiene having hydroxyl groups at both ends such as polytail H and polytail HA of Mitsubishi Chemical Corporation; liquid C5 polymer having hydroxyl groups at both ends, such as Poly-iP manufactured by Idemitsu Petrochemical Co., Ltd .; Examples include, but are not limited to, Epaul manufactured by Chemical Co., Ltd. and hydrogenated polyisoprene having hydroxyl groups at both ends, such as TH-1, TH-2, and TH-3 manufactured by Kuraray Co., Ltd.

  Examples of the polysiloxane polyols used in the present invention include compounds represented by general formulas (2) and (3).

General formula (2)

(X represents a hydroxyl group, R ¹ and R ² each represent an alkylene group having 1 to 6 carbon atoms, and n represents an integer of 5 or more.)

  General formula (3)

(Y represents a hydroxyl group, R ³ is an alkyl group having 1 to 6 carbon atoms, R ⁴ , R ⁵ and R ⁶ are each an alkylene group having 1 to 6 carbon atoms, and R ⁷ is a hydrogen atom or 1 to 1 carbon atoms. 6 represents an alkyl group, and n represents an integer of 5 or more.)

  Among these polyol compounds (a), polyester polyols composed of 1,4-cyclohexanedicarboxylic acid and 3-methyl-1,5-pentanediol, polycarbonate polyols using only 1,6-hexanediol as glycol, Polycarbonate diol using 1,6-hexanediol and 3-methyl-1,5-pentanediol as glycol, 1,9-nonanediol and 2-methyl-1,8-octanediol used as glycol Polycarbonate diol, polytetramethylene glycol, polypropylene glycol, or copolymer polyether polyol, polybutadiene polyol, hydrogenated polybutadiene polyol of tetramethylene glycol and neopentyl glycol Polysiloxane polyols and the like are excellent in flexibility, heat resistance, and hydrolysis resistance of the skeleton, and therefore excellent in electrical insulation, flexibility, heat resistance, moisture resistance, etc. as the carboxyl group-containing modified ester resin of the present invention. Particularly preferred. In the present invention, these polyol compounds (a) may be used alone or in combination.

  The compound (a-1) having at least one ethylenically unsaturated group and at least one hydroxyl group in one molecule optionally used in the present invention is a compound having one or more hydroxyl groups, It is a compound excluding the compound belonging to the “polyol compound (a)”. Representative examples thereof include, for example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acryl acrylates; diethylene glycol mono (meth) acrylate, dipropylene glycol mono (meth) acrylate, trimethylolpropane di (meth) ) Acrylate, glycerin di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, glycerin mono (meth) acrylate, reaction of dimethylolpropionic acid with 2-hydroxyethyl (meth) acrylate Product, reaction product of dimethylolpropionic acid and 2-hydroxypropyl (meth) acrylate, reaction product of dimethylolbutanoic acid and 2-hydroxyethyl (meth) acrylate Product, reaction product of dimethylolbutanoic acid and 2-hydroxypropyl (meth) acrylate, reaction product of epoxy compound having two epoxy groups in the molecule and (meth) acrylic acid or cinnamic acid, in the molecule And a reaction product of a phenol compound having two phenolic hydroxyl groups and glycidyl (meth) acrylate. Furthermore, a compound obtained by adding a cyclic ester such as ε-caprolactone to the hydroxyl group of the above compound can also be used. As an addition rate of (epsilon) -caprolactone, 1-2 mol is preferable with respect to 1 mol of said hydroxy (meth) alkyl acrylates. In the present invention, these compounds (a-1) having at least one ethylenically unsaturated group and at least one hydroxyl group in one molecule may be used alone or in combination. May be.

  Regarding the molar ratio of the polyol compound (a) used in the present invention to the compound (a-1) having at least one ethylenically unsaturated group and at least one hydroxyl group in one molecule, (a) The range of / (a-1) = 1/0 to 0.1 / 0.9 is preferable. When the molar ratio of (a-1) is more than 0.9, it becomes difficult to impart flexibility to the finally obtained coating film. On the other hand, by appropriately adjusting the molar ratio of (a-1) between 0 and 0.9, introducing a flexible skeleton derived from compound (a) into the main chain, and derived from compound (a-1) Therefore, the total physical properties as a resist can be improved.

  The tetrabasic acid dianhydride (b) used in the present invention is preferably a compound having 2 or more carboxylic acid anhydride groups in the molecule and having 8 to 50 carbon atoms. For example, pyromellitic anhydride 3,4,3 ′, 4′-benzophenone tetracarboxylic dianhydride, 2,3,2 ′, 3′-benzophenone tetracarboxylic dianhydride, 2,3,3 ′, 4′-benzophenone tetracarboxylic Acid dianhydride, 3,3 ′, 4,4′-diphenyltetracarboxylic dianhydride, 2,2 ′, 3,3′-diphenyltetracarboxylic dianhydride, 4,4′-oxydiphthalic acid dianhydride 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) propane dianhydride, 1,1-bis (2,3- Dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, 1,2,5 , 6-Naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,2,4,5-naphthalenetetracarboxylic dianhydride, 1,4,5,8 -Naphthalenetetracarboxylic dianhydride, phenanthrene-1,8,9,10-tetracarboxylic dianhydride, pyrazine-2,3,5,6-tetracarboxylic dianhydride, thiophene-2,3,4 5-tetracarboxylic dianhydride, bis (3,4-dicarboxyphenyl) dimethylsilane dianhydride, bis (3,4-dicarboxyphenyl) diphenylsilane dianhydride, 1,4-bis (3,4 -Dicarboxyphenyldimethylsilyl) benzene dianhydride, 1,3-bis (3,4-dicarboxyphenyl) -1,1,3,3-tetramethyldicyclohexane dianhydride, p-phenylbis (trimerit Acid monoester anhydride), ethylenetetracarboxylic dianhydride, 1,2,3,4-butanetetracarboxylic dianhydride, decahodronaphthalene-1,4,5,8-tetracarboxylic dianhydride , 4,8-dimethyl-1,2,3,5,6,7-hexahydronaphthalene-1,2,5,6-tetracarboxylic dianhydride, cyclopentane-1,2,3 4-tetracarboxylic dianhydride, pyrrolidine-2,3,4,5-tetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, bis (exo-bicyclo [2, 2,1] heptane-2,3-dicarboxylic anhydride) sulfone, bicyclo- (2,2,2) -oct (7) -ene-2,3,5,6-tetracarboxylic dianhydride, 2 , 2-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride, 2,2-bis [4- (3,4-dicarboxyphenoxy) phenyl] hexafluoropropane dianhydride, 4,4 ′ -Bis (3,4-dicarboxyphenoxy) diphenyl sulfide dianhydride, 1,4-bis (2-hydroxyhexafluoroisopropyl) benzenebis (trimellitic anhydride), 1,3-bis ( 2-hydroxyhexafluoroisopropyl) benzenebis (trimellitic anhydride), 5- (2,5-dioxotetrahydrofuryl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, tetrahydrofuran-2 , 3,4,5-tetracarboxylic acid dianhydride, commercially available products such as “Ricacid TMTA-C”, “Ricacid MTA-10”, “Ricacid MTA-15”, “Ricacid TMEG series” Examples include “Licacid TDA”. In the present invention, these tetrabasic acid dianhydrides (b) may be used alone or in combination.

  Among them, aromatic tetrabasic acid anhydrides such as pyromellitic anhydride and benzophenonetetracarboxylic dianhydride are particularly excellent in the present invention because of excellent reactivity with hydroxyl groups and heat resistance of the resin finally obtained. preferable.

  In the present invention, the synthesis conditions of the half ester compound (c) are not particularly limited, and can be performed under known conditions. For example, in a flask, a polyol compound (a), a compound (a-1) having at least one ethylenically unsaturated group and at least one hydroxyl group in one molecule, tetrabasic acid dianhydride (b) ) And a solvent, and the half ester compound (c) can be obtained by heating at 60 to 150 ° C. with stirring. At this time, an ethylenically unsaturated group may be added so as not to add a reaction catalyst such as a tertiary amino group-containing compound or the like to promote the reaction, or to cause gelation due to polymerization reaction or progress of polymerization. It is also possible to use a polymerization inhibitor or molecular oxygen.

  As polymerization inhibitors, hydroquinone, methylhydroquinone, pt-butylcatechol, 2-t-butylhydroquinone, 2,5-di-t-butylhydroquinone, trimethylhydroquinone, methoxyhydroquinone, p-benzoquinone, 2,5- Di-t-butylbenzoquinone, naphthoquinone, phenothiazine, N-oxyl compound and the like can be used. Further, even if molecular oxygen is present in the reaction vessel, there is an effect of inhibiting polymerization. For example, air or a mixed gas of air and an inert gas such as nitrogen may be blown into the reaction vessel so-called bubbling. In order to enhance the polymerization inhibition effect, it is preferable to use a polymerization inhibitor and molecular oxygen in combination.

  Next, the hydroxyl group-containing photosensitive ester resin (e) obtained in the second step of the present invention will be described. The hydroxyl group-containing photosensitive ester resin (e) can be obtained by reacting the half ester compound (c) with a compound (d) having an epoxy group or an oxetane group and an ethylenically unsaturated group. The carboxyl group in the compound (c), and the epoxy group or oxetane group in the compound (d) having an epoxy group or oxetane group and an ethylenically unsaturated group, carboxyl group / epoxy group or oxetane group = 1/0. It is preferable to make it react by the molar ratio of 1-1 / 1. When the epoxy group or oxetane group is less than the above molar ratio range, the double bond equivalent functioning as a photocrosslinking point in the finally obtained carboxyl group-containing photosensitive ester resin (A) becomes high, so that the desired heat resistance Properties and coating film resistance are difficult to obtain. Moreover, when there are more epoxy groups or oxetane groups than the range of the said molar ratio, it exists in the tendency for the flexibility of a final coating film to fall with the compound (e) which has an excess epoxy group or oxetane group, and an ethylenically unsaturated group. .

  The compound (e) having an epoxy group or oxetane group and an ethylenically unsaturated group used in the present invention may be any compound containing at least one epoxy group or oxetane group and an ethylenically unsaturated group in the molecule. There is no particular limitation. For example, glycidyl (meth) acrylate, glycidyl cinnamic acid, 4-hydroxybutyl (meth) acrylate glycidyl ether, glycidyl allyl ether, 2,3-epoxy-2-methylpropyl (meth) acrylate, (3,4-epoxycyclohexyl) Many hydroxyl-containing groups such as methyl (meth) acrylate, 4-vinyl-1-cyclohexene-1,2-epoxide, 1,3-butadiene monoepoxide, oxetanyl (meth) acrylate, oxetanylcinnamic acid, and pentaerythritol triacrylate Modification of most epoxide groups of polyfunctional acrylate groups by reacting epichlorohydrin with hydroxyl groups of functional acrylic monomers, and phenol novolac epoxy resins to acrylate groups with acrylic acid, etc. Epoxy of the compound which has two or more epoxy groups in the molecule to the carboxyl group of the polyfunctional acrylate group-containing monoepoxide and carboxyl group-containing polyfunctional acrylic monomer, in which one epoxy group remains in one molecule on average Examples include polyepoxy acrylate group-containing monoepoxides obtained by reacting a part of the groups. By reacting these epoxy groups or oxetane groups with the carboxyl groups in the half ester compound (c), hydroxyl groups A photosensitive ester resin (e) is obtained. In the present invention, the compound (e) having an epoxy group or oxetane group and an ethylenically unsaturated group may be used alone or in combination.

  Among them, glycidyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate glycidyl ether, and the like are particularly preferable in the present invention because they are highly reactive with carboxyl groups and are very excellent in photosensitivity.

  In the present invention, a compound having no ethylenically unsaturated group and having an epoxy group or oxetane group is used in combination with a compound (d) having an epoxy group or oxetane group and an ethylenically unsaturated group. You can also. In this case, the photosensitivity of the carboxyl group-containing photosensitive ester resin (A) of the present invention can be controlled more widely. Examples of the compound having no ethylenically unsaturated group and having an epoxy group or oxetane group of the present invention include styrene oxide, phenyl glycidyl ether, o-phenylphenol glycidyl ether, p-phenylphenol glycidyl ether, glycidyl cinnamon. Mate, methyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, decyl glycidyl ether, stearyl glycidyl ether, allyl glycidyl ether, glycidol, N-glycidyl phthalimide, 1,3-dibromophenyl glycidyl ether, Celoxide 2000 (Daicel Chemical Industries) And oxetane alcohol).

  In the present invention, the synthesis conditions of the hydroxyl group-containing photosensitive ester resin (e) are not particularly limited, and in the same manner as in the first step, the half ester compound (c) and the epoxy group are added to the flask in the presence of oxygen. Alternatively, the compound (d) having an oxetane group and an ethylenically unsaturated group, and a solvent are preferably charged and reacted while heating and stirring at 25 to 150 ° C., and a reaction catalyst suitable as necessary and A polymerization inhibitor of an ethylenically unsaturated group can be newly added.

  Next, the carboxyl group-containing photosensitive ester resin (A) obtained in the third step of the present invention will be described. The carboxyl group-containing photosensitive ester resin (A) of the present invention can be obtained by reacting the hydroxyl group-containing photosensitive ester resin (e) with the dibasic acid anhydride (f). The hydroxyl group in the reactive ester resin (e) and the acid anhydride group in the dibasic acid anhydride (f) are reacted at a molar ratio of hydroxyl group / acid anhydride group = 1 / 0.01 to 1/1. It is preferable to make them. If the acid anhydride group is less than the above molar ratio range, the carboxyl group concentration that functions as a crosslinking point in the finally obtained carboxyl group-containing photosensitive ester resin (A) decreases, so that desired heat resistance and alkali development are achieved. It becomes difficult to obtain solubility in the liquid. Moreover, when there are more acid anhydride groups than the range of the said molar ratio, it exists in the tendency for the flexibility of a final coating film, solder heat resistance, and insulation reliability to fall with an excess dibasic acid anhydride (f).

  The dibasic acid anhydride (f) used in the present invention is not particularly limited as long as it is a compound containing at least one acid anhydride group in the molecule, and only one kind may be used alone. A plurality of them may be used in combination. Specifically, phthalic anhydride, methyltetrahydrophthalic anhydride, methylhymic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methylpentahydrophthalic anhydride, methyltrihydrophthalic anhydride, trialkyltetrahydrophthalic anhydride Acid, methylcyclohexene dicarboxylic acid anhydride, het anhydride, tetrabromophthalic anhydride, succinic anhydride, maleic anhydride, glutaric anhydride, butyl succinic anhydride, hexyl succinic anhydride, octyl succinic anhydride, dodecyl succinic acid Acid anhydride, butyl maleic anhydride, pentyl maleic anhydride, hexyl maleic anhydride, octyl maleic anhydride, decyl maleic anhydride, dodecyl maleic anhydride, butyl glutamic anhydride, hexyl glutamic anhydride, Heptip Glutamic anhydride, octyl glutamic acid anhydride, decyl glutamic acid anhydride, and the like dodecyl glutamic acid anhydride. Of these, succinic anhydride, tetrahydrophthalic anhydride, and the like are particularly preferable in the present invention because of their excellent developability, pattern formability, and coating film resistance.

  In the present invention, the synthesis conditions of the carboxyl group-containing photosensitive ester resin (A) are not particularly limited, and the hydroxyl group-containing photosensitive ester resin (e) is added to the flask in the presence of oxygen in the same manner as in the second step. ), Dibasic acid anhydride (f), and solvent are charged, and the reaction is preferably carried out by heating and stirring at 25 to 150 ° C., and if necessary, suitable reaction catalyst and ethylenically unsaturated group A polymerization inhibitor can be newly added.

  The acid value of the carboxyl group-containing photosensitive ester resin (A) of the present invention obtained by the above steps is preferably 10 to 200 mgKOH / g, more preferably 30 to 150 mgKOH / g. When the acid value is less than 10 mg KOH / g, sufficient developability may be difficult to obtain. For example, the film may remain as a residue in a portion where the film is dissolved and removed during development. On the other hand, when the acid value exceeds 200 mgKOH / g, the solubility of the coating film in the developer increases, and even the portion that is desired to be photocured and left as a pattern is dissolved, and the shape of the pattern may deteriorate.

  The ethylenically unsaturated group equivalent of the carboxyl group-containing photosensitive ester resin (A) of the present invention is preferably 200 to 5000 g / eq, more preferably 300 to 3000 g / eq. When the ethylenically unsaturated group equivalent is less than 200 g / eq, the photosensitivity may be too high, and even the part to be removed by dissolving the film during development is cured by light, and a good pattern shape is obtained. There may not be. When the ethylenically unsaturated group equivalent exceeds 5000 g / eq, the photosensitivity may be too low, the portion to be photocured may not be sufficiently cured, and the pattern dissolves during development, thereby obtaining a good pattern shape. There may not be. The “ethylenically unsaturated group equivalent” as used in the present invention is a theoretical value calculated from the weight of raw materials used during the synthesis of the resin, and the weight of the resin is the ethylenically unsaturated group present in the resin. It is divided by the number of groups and corresponds to the weight of the resin per mole of ethylenically unsaturated groups, ie, the reciprocal of the ethylenically unsaturated group concentration.

  The weight average molecular weight of the carboxyl group-containing photosensitive ester resin (A) of the present invention is preferably 3000 to 100,000, more preferably 5000 to 60000. When the weight average molecular weight is less than 3000, sufficient solder heat resistance and flexibility may not be obtained. On the other hand, when the weight average molecular weight exceeds 100,000, the solder heat resistance is excellent, but the developability may be deteriorated, and the viscosity and handling at the time of coating may be problems.

  The solvent used for the synthesis of the carboxyl group-containing photosensitive ester resin (A) can be appropriately selected according to the final use and the solubility of the reaction product. For example, when a dry film type photosensitive solder resist is used as the final application, it is preferable to use a low-boiling solvent because the solvent needs to be quickly dried in the dry film preparation step. Examples of the low boiling point solvent in this case include methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate, tetrahydrofuran, toluene, isopropyl alcohol and the like. In addition, when liquid solder resist ink is used as the final application, it is necessary to suppress the volatilization of the solvent as much as possible in consideration of the process of kneading fillers and pigments with rolls in the ink preparation process and the storage stability as ink. Therefore, it is preferable to use a high boiling point solvent. Examples of the high boiling point solvent in this case include carbitol acetate, methoxypropyl acetate, cyclohexanone, diisobutyl ketone and the like.

  In the present invention, these solvents may be used alone or in combination, if necessary, and may be used in combination. Or a solvent may be added.

  The photosensitive resin composition of the present invention is at least one selected from the group consisting of the carboxyl group-containing photosensitive ester resin (A), an epoxy group-containing compound, an isocyanate group-containing compound, and a blocked isocyanate group-containing compound. A compound (B) and a photoinitiator (C) are included. Here, at least one compound (B) selected from the group consisting of an epoxy group-containing compound, an isocyanate group-containing compound, and a blocked isocyanate group-containing compound [hereinafter also simply referred to as “compound (B)”. ] Will be described. The photosensitive resin composition of this invention uses a compound (B) as a hardening | curing agent of the carboxyl group-containing photosensitive ester resin (A) mentioned above.

  The epoxy group-containing compound used as (B) in the present invention is not particularly limited as long as it is a compound containing an epoxy group in the molecule. Moreover, the epoxy group-containing compound described here may or may not have an ethylenically unsaturated group. For example, examples of the compound having one epoxy group in the molecule include compounds such as N-glycidylphthalimide, glycidol, and glycidyl (meth) acrylate. These can be suitably used for the purpose of controlling the crosslink density of the cured product by using together with a compound having two or more epoxy groups in the molecule exemplified below as needed. Examples of the compound containing two or more epoxy groups in the molecule include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, bisphenol A / epichlorohydrin type epoxy resin, Bisphenol F / epichlorohydrin type epoxy resin, bisphenol S / epichlorohydrin type epoxy resin, bisphenol AD / epichlorohydrin type epoxy resin, biphenol / epichlorohydrin type epoxy resin, ethylene oxide adduct of bisphenol A or Propylene oxide adduct epichlorohydrin type epoxy resin, glycerin / epichlorohydrin adduct polyglycidyl ether, naphthalenediol diglycidyl ether, resorcino Rudiglycidyl ether, polybutadiene diglycidyl ether, hydroquinone diglycidyl ether, dibromoneopentyl glycol diglycidyl ether, neopentyl glycol diglycidyl ether, hexahydrophthalic acid diglycidyl ester, hydrogenated bisphenol A type diglycidyl ether, polypropylene glycol diglycidyl Ether, diphenylsulfone diglycidyl ether, dihydroxybenzophenone diglycidyl ether, biphenol diglycidyl ether, diphenylmethane diglycidyl ether, bisphenol full orange glycidyl ether, biscresol full orange glycidyl ether, bisphenoxyethanol full orange glycidyl ether, 1,3-bis ( N, N-diglycidyl Minomethyl) cyclohexane, N, N-diglycidylaniline, N, N-diglycidyltoluidine, Japanese Patent Application Laid-Open Nos. 2004-156024, 2004-315595, and 2004-323777. And an epoxy compound having a structure represented by the following formulas (4) to (6).

Formula (4)

Formula (5)

Formula (6)

  Further, trishydroxyethyl isocyanurate triglycidyl ether, triglycidyl isocyanurate, “Epicoat 1031S”, “Epicoat 1032H60”, “Epicoat 604”, “Epicoat 630” manufactured by Mitsubishi Chemical Corporation, phenol novolac epoxy resin, cresol Novolac type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene type epoxy resin, polyglycidyl ether of ethylene glycol / epichlorohydrin adduct, pentaerythritol polyglycidyl ether, trimethylol propane poly, disclosed in JP-A-2001-240654 Examples thereof include glycidyl ether, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, and the like. Moreover, the compound which has other thermosetting groups other than an epoxy group can also be used. For example, the silane modified epoxy resin currently disclosed by Unexamined-Japanese-Patent No. 2001-59011 and 2003-48953 is mentioned.

  In particular, isocyanurate ring-containing epoxy compounds such as trishydroxyethyl isocyanurate triglycidyl ether and triglycidyl isocyanurate are preferred because they tend to improve the adhesion strength to polyimide and copper when used in the present invention. Also, “Epicoat 1031S”, “Epicoat 1032H60”, “Epicoat 604”, and “Epicoat 630” manufactured by Mitsubishi Chemical Corporation are highly functional in the present invention because they are multifunctional and have excellent heat resistance. Aliphatic epoxy compounds and epoxy compounds described in JP-A Nos. 2004-156024, 2004-315595, and 2004-323777 are preferable because they are excellent in flexibility of a cured coating film. Further, the dicyclopentadiene type epoxy compound, the phenol novolak type epoxy resin, the cresol novolak type epoxy resin, the biphenol / epichlorohydrin type epoxy resin, etc. described in JP-A No. 2001-240654 are thermally cured in the present invention. It is excellent in terms of durability of a cured coating film including properties, hygroscopicity and heat resistance, and is preferable.

  The isocyanate group-containing compound is not particularly limited as long as it is a compound having an isocyanate group in the molecule. Specific examples of the diisocyanate compound include aromatic diisocyanates having 4 to 50 carbon atoms, aliphatic diisocyanates, araliphatic diisocyanates, and alicyclic diisocyanates.

  Examples of the aromatic diisocyanate include 1,3-phenylene diisocyanate, 4,4′-diphenyl diisocyanate, 1,4-phenylene diisocyanate, 4,4′-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6- Tolylene diisocyanate, 4,4'-toluidine diisocyanate, 2,4,6-triisocyanate toluene, 1,3,5-triisocyanate benzene, dianisidine diisocyanate, 4,4'-diphenyl ether diisocyanate, 4,4 ', 4 "-Triphenylmethane triisocyanate etc. can be mentioned.

  Examples of the aliphatic diisocyanate include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, dodecamethylene diisocyanate, 2 4,4-trimethylhexamethylene diisocyanate and the like.

  Examples of the araliphatic diisocyanate include ω, ω′-diisocyanate-1,3-dimethylbenzene, ω, ω′-diisocyanate-1,4-dimethylbenzene, ω, ω′-diisocyanate-1,4-diethylbenzene, 1 , 4-tetramethylxylylene diisocyanate, 1,3-tetramethylxylylene diisocyanate, and the like.

  Examples of the alicyclic diisocyanate include 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate [alias: isophorone diisocyanate], 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate. , Methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 4,4′-methylenebis (cyclohexyl isocyanate), 1,3-bis (isocyanatomethyl) cyclohexane, 1,4-bis (isocyanate methyl) A cyclohexane etc. can be mentioned.

  Specific examples of the isocyanate group-containing compound having one or more isocyanate groups in the molecule include (meth) acryloyloxyethyl isocyanate, monofunctional isocyanate having one isocyanate group in one molecule, , 1-bis [(meth) acryloyloxymethyl] ethyl isocyanate, vinyl isocyanate, allyl isocyanate, (meth) acryloyl isocyanate, isopropenyl-α, α-dimethylbenzyl isocyanate, and the like. In addition, 1,6-diisocyanatohexane, isophorone diisocyanate, 4,4′-diphenylmethane diisocyanate, polymeric diphenylmethane diisocyanate, xylylene diisocyanate, tolylene 2,4-diisocyanate, toluene diisocyanate, 2,4-diisocyanic acid Toluene, hexamethylene diisocyanate, 4-methyl-m-phenylene diisocyanate, naphthylene diisocyanate, paraphenylene diisocyanate, tetramethylxylylene diisocyanate, cyclohexylmethane diisocyanate, hydrogenated xylylene diisocyanate, cyclohexyl diisocyanate, tolidine diisocyanate, 2,2 , 4-Trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate Nitrate, m-tetramethylxylylene diisocyanate, p-tetramethylxylylene diisocyanate, diisocyanate ester compounds such as dimer acid diisocyanate and hydroxyl group, carboxyl group, and amide group-containing vinyl monomers are reacted in equimolar amounts. It can be used as an ester compound.

  Examples of the polyfunctional isocyanate having 3 or more isocyanate groups in one molecule include aliphatic polyisocyanates such as aromatic polyisocyanates and lysine triisocyanates, araliphatic polyisocyanates, and alicyclic polyisocyanates. Examples thereof include trimethylolpropane adducts of diisocyanate described above, burettes reacted with water, and trimers having an isocyanurate ring.

  The blocked isocyanate group-containing compound is not particularly limited as long as the isocyanate group is an isocyanate group-containing compound protected with ε-caprolactam, MEK oxime, or the like. Specific examples include those obtained by blocking the isocyanate group of the isocyanate group-containing compound with ε-caprolactam, MEK oxime, cyclohexanone oxime, pyrazole, phenol, and the like.

  In the present invention, the compound (B) may be used alone or in combination. The amount of the compound (B) used may be determined in consideration of the application of the curable resin composition of the present invention, and is not particularly limited, but the carboxyl group-containing photosensitive ester resin (A) 100 weight. It is preferable to add at a ratio of 0.5 to 100 parts by weight, and more preferable to add at a ratio of 1 to 80 parts by weight. By using a compound (B), since the crosslinking density of the photosensitive resin composition of this invention can be adjusted to an appropriate value, the various physical properties of the coating film after hardening can be improved further. When the amount of the compound (B) used is less than 0.5 parts by weight, the crosslinking density of the coating film after heat curing becomes too low, and the desired adhesive strength and heat resistance may be insufficient. On the other hand, if the amount used is more than 100 parts by weight, the crosslinking density after heat curing becomes too high, and as a result, the flexibility and flexibility of the coating film may be lowered, and the adhesive strength may be significantly deteriorated. .

  Next, the photopolymerization initiator (C) will be described. The photopolymerization initiator (C) is added when the photosensitive compound is cured by ultraviolet rays. The photopolymerization initiator is not particularly limited as long as it has a function capable of initiating vinyl polymerization by photoexcitation. For example, a monocarbonyl compound, a dicarbonyl compound, an acetophenone compound, a benzoin ether compound, an acylphosphine oxide compound, an aminocarbonyl A compound etc. can be used.

  Specific examples of monocarbonyl compounds include benzophenone, 4-methyl-benzophenone, 2,4,6-trimethylbenzophenone, methyl-o-benzoylbenzoate, 4-phenylbenzophenone, 4- (4-methylphenylthio) phenyl-enetanone. 3,3′-dimethyl-4-methoxybenzophenone, 4- (1,3-acryloyl-1,4,7,10,13-pentaoxotridecyl) benzophenone, 3,3′4,4′-tetra ( t-butylperoxycarbonyl) benzophenone, 4-benzoyl-N, N, N-trimethylbenzenemethammonium chloride, 2-hydroxy-3- (4-benzoyl-phenoxy) -N, N, N-trimethyl-1-propanamine Hydrochloride, 4-benzoyl-N, N-dimethyl-n- [2 (1-Oxo-2-propenyloxyethyl)] metaammonium bromide, 2- / 4-iso-propylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1-chloro-4-propoxythioxanthone 2-hydroxy-3- (3,4-dimethyl-9-oxo-9Hthioxanthone-2-yloxy) -N, N, N-trimethyl-1-propanamine hydrochloride, benzoylmethylene-3-methylnaphtho (1, 2-d) thiazoline and the like.

  Examples of the dicarbonyl compound include 1,7,7-trimethyl-bicyclo [2.1.1] heptane-2,3-dione, benzyl, 2-ethylanthraquinone, 9,10-phenanthrenequinone, and methyl-α-oxobenzene. Examples include acetate and 4-phenylbenzyl.

  Examples of the acetophenone compound include 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- (4-isopropylphenyl) 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- ( 4-Isopropylphenyl) 2-hydroxy-di-2-methyl-1-phenylpropan-1-one, 1-hydroxy-cyclohexyl-phenyl ketone, 2-hydroxy-2-methyl-1-styrylpropan-1-one polymerization , Diethoxyacetophenone, dibutoxyacetophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2,2-diethoxy-1,2-diphenylethane-1-one, 2-methyl-1- [4- (Methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethyla No-1- (4-morpholino-phenyl) butan-1-one, 1-phenyl-1,2-propanedione-2- (o-ethoxycarbonyl) oxime, 3,6-bis (2-methyl-2- Morpholino-propanonyl) -9-butylcarbazole and the like.

Examples of the benzoin ether compound include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and benzoin normal butyl ether.
Examples of the acylphosphine oxide compound include 2,4,6-trimethylbenzoyldiphenylphosphine oxide and 4-n-propylphenyl-di (2,6-dichlorobenzoyl) phosphine oxide.

  Examples of aminocarbonyl compounds include methyl-4- (dimethylamino) benzoate, ethyl-4- (dimethylamino) benzoate, 2-nbutoxyethyl-4- (dimethylamino) benzoate, isoamyl-4- (dimethylamino) benzoate, 2- (dimethylamino) ethyl benzoate, 4,4′-bis-4-dimethylaminobenzophenone, 4,4′-bis-4-diethylaminobenzophenone, 2,5′-bis- (4-diethylaminobenzal) cyclopenta Non etc. are mentioned.

  In particular, in the present invention, when 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one and thioxanthones are used in combination, the photosensitivity is extremely low but the cost is very low. This is particularly preferable.

  These are not limited to the above compounds, and any compounds can be used as long as they have the ability to initiate polymerization by ultraviolet rays. These can be used alone or in combination, and the amount used is not limited, but is added in the range of 1 to 20 parts by weight with respect to 100 parts by weight as the total dry weight of the carboxyl group-containing photosensitive ester resin (A). It is preferable. Moreover, a well-known organic amine can also be added as a sensitizer.

  The photosensitive resin composition of the present invention includes the carboxyl group-containing photosensitive ester resin (A), a compound (B) that is at least one selected from an epoxy group-containing compound, a non-blocked isocyanate compound, and a blocked isocyanate compound. In addition to the photopolymerization initiator (C), it is more preferable to include a thermosetting aid (D). The thermosetting aid (D) referred to in the present invention represents a compound that contributes directly or catalytically to the curing reaction during thermosetting.

  Examples of the compound that directly contributes to the curing reaction during thermosetting include amino resins, phenol resins, polyfunctional polycarboxylic acid anhydrides, polyfunctional vinyl ether compounds, high molecular weight polycarbodiimides, and aziridine compounds.

  Examples of amino resins and phenol resins include addition compounds of urea, melamine, benzoguanamine, phenol, cresols, bisphenols, and the like with formaldehyde, or partial condensates thereof.

  The polyfunctional polycarboxylic acid anhydride is a compound having two or more carboxylic acid anhydride groups and is not particularly limited, but tetracarboxylic dianhydride, hexacarboxylic dianhydride, hexacarboxylic dianhydride And polyvalent carboxylic acid anhydrides such as maleic anhydride copolymer resins. In addition, polycarboxylic acid, polycarboxylic acid ester, polycarboxylic acid half ester, and the like that can be converted into an anhydride via a dehydration reaction during the reaction are “compounds having two or more carboxylic acid anhydride groups” in the present invention. "include.

  More specifically, as tetracarboxylic dianhydride, pyromellitic anhydride, benzophenone tetracarboxylic dianhydride, biphenyl tetracarboxylic dianhydride, oxydiphthalic dianhydride, diphenyl sulfone tetracarboxylic dianhydride, Diphenyl sulfide tetracarboxylic dianhydride, butane tetracarboxylic dianhydride, perylene tetracarboxylic dianhydride, naphthalene tetracarboxylic dianhydride, "Ricacid TMTA-C", "Ricacid MTA-" manufactured by Shin Nippon Chemical Co., Ltd. 10 ”,“ Licacid MTA-15 ”,“ Licacid TMEG series ”,“ Licacid TDA ”, and the like.

   Examples of maleic anhydride copolymer resins include SMA resin series manufactured by Sartomer, GSM series manufactured by Gifu Shellac Co., Ltd., styrene-maleic anhydride copolymer resins, p-phenylstyrene-maleic anhydride copolymer resins, polyethylene- Α-olefin-maleic anhydride copolymer resin such as maleic anhydride, “VEMA” (copolymer of methyl vinyl ether and maleic anhydride) manufactured by Daicel Chemical Industries, Ltd., and acrylic anhydride modified maleic anhydride (“Aurolen series”) ": Nippon Paper Chemical Co., Ltd.), maleic anhydride copolymer acrylic resin, and the like.

  Specific examples of the polyfunctional vinyl ether compound include ethylene glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, tetraethylene glycol divinyl ether, pentaerythritol divinyl ether, propylene glycol divinyl ether, dipropylene glycol divinyl ether, and tripropylene glycol. Divinyl ether, neopentyl glycol divinyl ether, 1,4-butanediol divinyl ether, 1,6-hexanediol divinyl ether, glycerin divinyl ether, trimethylolpropane divinyl ether, 1,4-dihydroxylcyclohexane divinyl ether, 1,4 -Dihydroxymethylcyclohexanedivinyl ether, Hyde Quinone divinyl ether, ethylene oxide modified hydroquinone divinyl ether, ethylene oxide modified resorcin divinyl ether, ethylene oxide modified bisphenol A divinyl ether, ethylene oxide modified bisphenol S divinyl ether, glycerin trivinyl ether, sorbitol tetravinyl ether, trimethylolpropane trivinyl ether, pentaerythritol Examples include trivinyl ether, pentaerythritol tetravinyl ether, dipentaerythritol hexavinyl ether, dipentaerythritol polyvinyl ether, ditrimethylolpropane tetravinyl ether, and ditrimethylolpropane polyvinyl ether.

  Examples of the high molecular weight polycarbodiimides include Nisshinbo's Carbodilite series. Among these, Carbodilite V-01, 03, 05, 07, and 09 are preferable because of excellent compatibility with organic solvents.

  Examples of the aziridine compound include 2,2′-bishydroxymethylbutanol tris [3- (1-aziridinyl) propionate], 4,4′-bis (ethyleneiminocarbonylamino) diphenylmethane, and the like.

  Other compounds that directly contribute to the curing reaction during thermal curing include benzoxazine compounds, benzocyclobutene compounds, maleimide compounds, nadiimide compounds, allyl nadiimide compounds, melamine compounds, and guanamine compounds, which are cured by heating. Any of them can be used effectively. These photopolymerizable groups, functional groups capable of reacting with carboxyl groups, and compounds having functional groups capable of reacting with hydroxyl groups can improve the heat resistance of the coating film after curing, and are therefore used more effectively. be able to.

Examples of compounds that contribute catalytically to the curing reaction during heat curing include tertiary amines such as triethylamine, tributylamine, benzyldimethylamine, 2,4,6-tris (dimethylaminomethyl) phenol, and N-methylpiperazine. And salts thereof;
2-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-methylimidazole, 2,4-dicyano-6- [2-methylimidazolyl-1] -Imidazoles such as ethyl-S-triazine and salts thereof;
1,5-diazabicyclo [5,4,0] -7-undecane, 1,5-diazabicyclo [4,3,0] -5-nonene, 1,4-diabicyclo [2,2,2,] octane, etc. Diazabicyclo compounds;
Phosphines such as tributylphosphine, triphenylphosphine, tris (dimethoxyphenyl) phosphine, tris (hydroxypropyl) phosphine, tris (cyanoethyl) phosphine;
Phosphonium salts such as tetraphenylphosphonium tetraphenylborate, methyltributylphosphonium tetraphenylborate, methyltricyanoethylphosphonium tetraphenylborate;
In addition, dicyandiamide, carboxylic acid hydrazide, and the like can be cited as compounds that are catalytic and that directly contribute to the curing reaction. Examples of the carboxylic acid hydrazide include succinic acid hydrazide and adipic acid hydrazide.

  These thermosetting aids (D) may be used alone or in combination of two or more. The amount of the thermosetting aid (D) used may be determined in consideration of the use of the photosensitive resin composition, and is not particularly limited, but the carboxyl group-containing photosensitive ester resin (A) is 100 weights. Is more preferably in the range of 0.1 to 100 parts by weight, and still more preferably in the range of 0.5 to 80 parts by weight. Thereby, since the crosslinking density of the photosensitive resin composition can be adjusted to an appropriate value, various physical properties of the photosensitive resin composition can be further improved. If the amount of the thermosetting aid (D) used is less than 0.1 parts by weight, the crosslinking density of the coating after heat curing becomes too low, and the cohesive strength and durability may be insufficient. Further, if the amount used is more than 100 parts by weight, the crosslinking density after heat curing becomes too high, and as a result, the flexibility and flexibility of the coating film may be lowered, and the warpage of the substrate may be remarkably deteriorated. is there.

  The photosensitive resin composition of this invention may contain resin other than the above-mentioned (A) as needed. Examples of resins other than (A) include acrylic resins, polyester resins, urethane resins, urea resins, urethane urea resins, epoxy resins, polyamide resins, and polyimide resins. Those containing a carboxyl group are preferred from the viewpoint of developability, and those containing an ethylenically unsaturated group are preferred from the viewpoint of resolution. In this invention, when it contains resin other than (A), it can be used individually or in combination.

  The ethylenically unsaturated group-containing compound here is not particularly limited as long as it has an ethylenically unsaturated double bond in the structure. Examples include alkyl (meth) acrylates, alkylene glycol (meth) acrylates, compounds having a carboxyl group and an ethylenically unsaturated group, (meth) acrylate compounds having a hydroxyl group, and nitrogen-containing (meth) acrylate compounds. Monofunctional and polyfunctional compounds can be used as appropriate. From the viewpoint of photocurability and hard coat properties of the coating film, polyfunctional ones are preferred.

  More specifically, as the alkyl-based (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, 2-ethylhexyl ( (Meth) acrylate, heptyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) Acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate, nonadeci When there is an alkyl (meth) acrylate having an alkyl group having 1 to 22 carbon atoms such as (meth) acrylate, icosyl (meth) acrylate, heicosyl (meth) acrylate, docosyl (meth) acrylate, etc. Preferably, an alkyl (meth) acrylate having an alkyl group having 2 to 10 carbon atoms, more preferably 2 to 8 carbon atoms is used.

Examples of the alkylene glycol (meth) acrylate include diethylene glycol mono (meth) acrylate, triethylene glycol mono (meth) acrylate, tetraethylene glycol mono (meth) acrylate, hexaethylene glycol mono (meth) acrylate, and polyethylene glycol. Mono (meth) acrylate, dipropylene glycol mono (meth) acrylate, tripropylene glycol mono (meth) acrylate, tetrapropylene glycol mono (meth) acrylate, polytetramethylene glycol mono (meth) acrylate, etc .;
Mono (meth) acrylate having a hydroxyl group at the terminal and a polyoxyalkylene chain;
Methoxyethylene glycol (meth) acrylate, methoxydiethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, methoxytetraethylene glycol (meth) acrylate, ethoxytetraethylene glycol (meth) acrylate, propoxytetraethylene glycol (meth) acrylate , N-butoxytetraethylene glycol (meth) acrylate, n-pentoxytetraethylene glycol (meth) acrylate, tripropylene glycol (meth) acrylate, tetrapropylene glycol (meth) acrylate, methoxytripropylene glycol (meth) acrylate, methoxy Tetrapropylene glycol (meth) acrylate, ethoxytetrapropyleneglycol (Meth) acrylate, propoxytetrapropylene glycol (meth) acrylate, n-butoxytetrapropylene glycol (meth) acrylate, n-pentoxytetrapropylene glycol (meth) acrylate, polytetramethylene glycol (meth) acrylate, methoxypolytetra Methylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, ethoxypolyethylene glycol (meth) acrylate, mono (meth) acrylate having an alkoxy group at the terminal and a polyoxyalkylene chain;
Phenoxydiethylene glycol (meth) acrylate, phenoxyethylene glycol (meth) acrylate, phenoxytriethylene glycol (meth) acrylate, phenoxytetraethylene glycol (meth) acrylate, phenoxyhexaethylene glycol (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, Examples thereof include polyoxyalkylene (meth) acrylates having a phenoxy group or an aryloxy group at the terminal, such as phenoxytetrapropylene glycol (meth) acrylate.

  Examples of the compound having a carboxyl group and an ethylenically unsaturated group include maleic acid, fumaric acid, itaconic acid, citraconic acid, alkyl or alkenyl monoesters thereof, and phthalic acid β- (meth) acryloxyethyl monoester. Ester, isophthalic acid β- (meth) acryloxyethyl monoester, terephthalic acid β- (meth) acryloxyethyl monoester, succinic acid β- (meth) acryloxyethyl monoester, acrylic acid, methacrylic acid, crotonic acid, Cinnamic acid and the like can be exemplified.

  Moreover, as a compound which has a hydroxyl group and an ethylenically unsaturated group, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, glycerol mono (meth) acrylate, 4-hydroxyvinylbenzene and the like are listed.

Examples of the compound having a nitrogen atom and an ethylenically unsaturated group include (meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl- (meth) acrylamide, N-ethoxymethyl- (meth) acrylamide, Monoalkylol (meth) acrylamides such as N-propoxymethyl- (meth) acrylamide, N-butoxymethyl- (meth) acrylamide, N-pentoxymethyl- (meth) acrylamide, N, N-di (methylol) acrylamide, N-methylol-N-methoxymethyl (meth) acrylamide, N, N-di (methoxymethyl) acrylamide, N-ethoxymethyl-N-methoxymethylmethacrylamide, N, N-di (ethoxymethyl) acrylamide, N-ethoxy Methyl-N-propoxy Tylmethacrylamide, N, N-di (propoxymethyl) acrylamide, N-butoxymethyl-N- (propoxymethyl) methacrylamide, N, N-di (butoxymethyl) acrylamide, N-butoxymethyl-N- (methoxymethyl) ) Acrylamide unsaturated compounds such as dialkyl (meth) acrylamides such as methacrylamide, N, N-di (pentoxymethyl) acrylamide, N-methoxymethyl-N- (pentoxymethyl) methacrylamide, dimethylaminoethyl (meta ) Unsaturated compounds having dialkylamino groups such as acrylate, diethylaminoethyl (meth) acrylate, methylethylaminoethyl (meth) acrylate, dimethylaminostyrene, diethylaminostyrene, and C as a counter ion ^{-, Br} -, I ^- a halogen ion or, QSO ^3-: having (Q alkyl group having 1 to 12 carbon atoms) can be exemplified by quaternary ammonium salts of dialkylamino group-containing unsaturated compound.

Further, other unsaturated compounds include perfluoromethylmethyl (meth) acrylate, perfluoroethylmethyl (meth) acrylate, 2-perfluorobutylethyl (meth) acrylate, 2-perfluorohexylethyl (meth) acrylate, 2 -Perfluorooctylethyl (meth) acrylate, 2-perfluoroisononylethyl (meth) acrylate, 2-perfluorononylethyl (meth) acrylate, 2-perfluorodecylethyl (meth) acrylate, perfluoropropylpropyl (meth) ) Acrylate, perfluorooctylpropyl (meth) acrylate, perfluorooctyl amyl (meth) acrylate, perfluorooctyl undecyl (meth) acrylate, etc. Perfluoroalkyl (meth) acrylates having Kill group;
Perfluoroalkyl group-containing vinyl monomers such as perfluoroalkyl, alkylenes such as perfluorobutylethylene, perfluorohexylethylene, perfluorooctylethylene, perfluorodecylethylene;
Alkoxysilyl group-containing vinyl compounds such as vinyltrichlorosilane, vinyltris (βmethoxyethoxy) silane, vinyltriethoxysilane, γ- (meth) acryloxypropyltrimethoxysilane and derivatives thereof;
Examples thereof include glycidyl group-containing (meth) acrylates such as glycidyl (meth) acrylate and 3,4-epoxycyclohexyl (meth) acrylate, and one or more types can be appropriately selected from these groups and used.

Examples of fatty acid vinyl compounds include vinyl acetate, vinyl butyrate, vinyl propionate, vinyl hexanoate, vinyl caprylate, vinyl laurate, vinyl palmitate, and vinyl stearate;
Examples of alkyl vinyl ether compounds include butyl vinyl ether and ethyl vinyl ether;
As the α-olefin compound, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene and the like;
As vinyl compounds, allyl compounds such as allyl acetate, allyl alcohol, allylbenzene, allyl cyanide, vinyl cyanide, vinylcyclohexane, vinyl methyl ketone, styrene, α-methylstyrene, 2-methylstyrene, chlorostyrene, etc .;
As an ethynyl compound, acetylene, ethynylbenzene, ethynyltoluene, 1-ethynyl-1-cyclohexanol and the like;
Can also be used.

  Next, a polyfunctional compound having two or more ethylenically unsaturated groups is specifically exemplified.

  First, an aliphatic compound is illustrated among the compounds which have an ethylenically unsaturated group. Specifically, 1,3-propanediol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, Bis (acryloxy neopentyl glycol) adipate, bis (methacryloxy neopentyl glycol) adipate, epichlorohydrin modified 1,6-hexanediol di (meth) acrylate: Nippon Kayaku Kayrad R-167, hydroxypivalate neopentyl glycol di (Meth) acrylate, caprolactone-modified hydroxypivalic acid neopentyl glycol di (meth) acrylate: Nippon Kayaku Kayrad HX series alkyl type (meth) acrylate, ethylene glycol di (meth) acrylate , Diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, epichlorohydrin modified ethylene glycol di (meth) acrylate: Nagase Sangyo Denacol DA (M) -811, epichlorohydrin modified diethylene glycol di (meth) acrylate: Nagase Sangyo Denacol DA (M) -851, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate , Tetrapropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, epichlorohydrin modified propylene Recall di (meth) acrylate: alkylene glycol type (meth) acrylate such as Nagase Sangyo Denacol DA (M) -911, trimethylolpropane tri (meth) acrylate, ditrimethylolpropane tri (meth) acrylate, neopentyl glycol modified trimethylolpropane Di (meth) acrylate: Nippon Kayaku Kayrad R-604, ethylene oxide modified trimethylolpropane tri (meth) acrylate: Sartomer SR-454, propylene oxide modified trimethylolpropane tri (meth) acrylate: Nippon Kayaku TPA- 310, trichlorohydrin-modified trimethylolpropane tri (meth) acrylate: trimethylolpropane type (meth) acrylate such as Nagase Sangyo DA (M) -321, penta Erythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, stearic acid modified pentaerythritol di (meth) acrylate: Toa Synthetic Aronix M-233, dipentaerythritol hexa (meth) acrylate, dipentaerythritol monohydroxypenta (meta ) Acrylate, alkyl-modified dipentaerythritol poly (meth) acrylates: Kayarad D-310, 320, 330 made by Nippon Kayaku, etc. Caprolactone-modified dipentaerythritol poly (meth) acrylates: Kayrad DPCA-20 made by Nippon Kayaku Pentaerythritol type (meth) acrylate such as 30, 60, 120, glycerol di (meth) acrylate, epichlorohydrin modified glycerol tri (meth) acrylate Rate: Nagase Sangyo Denacol DA (M) -314, glycerol type (meth) acrylate such as triglycerol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, tricyclopentanyl di (meth) acrylate, cyclohexyldi (Meth) acrylate, methoxylated cyclohexyl di (meth) acrylate: cycloaliphatic (meth) acrylate such as Sanyo Kokusaku Pulp CAM-200, tris (acryloxyethyl) isocyanurate: Toa Gosei Aronix M-315, Tris (methacryloxy) Isocyanurate type (meth) acrylates such as ethyl) isocyanurate, caprolactone-modified tris (acryloxyethyl) isocyanurate, caprolactone-modified tris (methacryloxyethyl) isocyanurate, etc. It is below.

  Of the compounds having an ethylenically unsaturated group, aromatic compounds are exemplified. For example, hydroquinone, resorcin, catechol, pyrogallol, bisphenol A di (meth) acrylate, ethi (propyrene) oxide-modified bisphenol A di (meth) acrylate [“ethi (propyrene) oxide” means “ethylene oxide” or “propylene” Means "oxide". The same applies hereinafter. ], Bisphenol F di (meth) acrylate, Ethi (propi) ylene oxide modified bisphenol F di (meth) acrylate, Bisphenol S di (meth) acrylate, Ethi (propi) lene oxide modified bisphenol S di (meth) acrylate, Epichlorohydrin modified (Meth) acrylate compounds having aromatic groups such as di (meth) acrylate phthalate, tetrachlorobisphenol S ethyl (propylene) oxide modified di (meth) acrylate, tetrabromobisphenol S ethyl (propylene) oxide modified di (meth) Examples thereof include styrenes having an aromatic group substituted with a halogen atom having an atomic weight of chlorine atom or more, such as acrylate, and (meth) acrylate compounds.

  Furthermore, from the viewpoint of coating strength and scratch resistance, polyfunctional (meth) acrylates such as urethane (meth) acrylate, epoxy (meth) acrylate, and polyester (meth) acrylate are suitable as the ethylenically unsaturated group-containing compound. Can be used for Epoxy (meth) acrylate is obtained by esterifying an epoxy group of an epoxy resin with (meth) acrylic acid and converting the functional group to (meth) acrylate, and (meth) acrylic acid adduct to bisphenol A type epoxy resin. And (meth) acrylic acid adducts to novolac epoxy resins. Urethane (meth) acrylates are, for example, those obtained by reacting diisocyanates with (meth) acrylates having a hydroxyl group, and isocyanate group-containing urethane prepolymers obtained by reacting polyols and polyisocyanates under conditions of excess isocyanate groups. Some are obtained by reacting polymers with (meth) acrylates having a hydroxyl group. Alternatively, a hydroxyl group-containing urethane prepolymer obtained by reacting a polyol and a polyisocyanate under hydroxyl-excess conditions can be obtained by reacting with a (meth) acrylate having an isocyanate group.

The following can be illustrated as a commercial item.
Toa Gosei Co., Ltd .: Aronix M-400, Aronix M-402, Aronix M-310, Aronix M-408, Aronix M-450, Aronix M-7100, Aronix M-8030, Aronix M-8060;
Osaka Organic Chemical Industry Co., Ltd .: Biscote # 400;
Kayaku Sartomer Co., Ltd .: SR-295;
Made by Daicel UCB Corporation: DPHA, Ebecryl 220, Ebecryl 1290K, Ebecryl 5129, Ebecryl 2220, Ebecryl 6602;
Shin-Nakamura Chemical Co., Ltd .: NK Ester A-TMMT, NK Oligo EA-1020, NK Oligo EMA-1020, NK Oligo EA-6310, NK Oligo EA-6320, NK Oligo EA-6340, NK Oligo MA-6, NK oligo U-4HA, NK oligo U-6HA, NK oligo U-324A;
Manufactured by BASF: LaromerEA81;
San Nopco Co., Ltd .: Photomer 3016;
Arakawa Chemical Industries, Ltd .: beam set 371, beam set 575, beam set 577, beam set 700, beam set 710;
Manufactured by Negami Kogyo Co., Ltd .: Art Resin UN-3320HA, Art Resin UN-3320HB, Art Resin UN-3320HC, Art Resin UN-3320HS, Art Resin UN-9000H, Art Resin UN-901T, Art Resin HDP, Art Resin HDP- 3, Art Resin H61;
Nippon Synthetic Chemical Industry Co., Ltd .: Purple light UV-7600B, Purple light UV-7610B, Purple light UV-7620EA, Purple light UV-7630B, Purple light UV-1400B, Purple light UV-1700B, Purple light UV-6300B;
Kyoeisha Chemical Co., Ltd .: Light acrylate PE-4A, Light acrylate DPE-6A, UA-306H, UA-306T, UA-306I;
Nippon Kayaku Co., Ltd .: KAYARAD DPHA, KAYARAD DPHA2C, KAYARAD DPHA-40H, KAYARAD D-310, KAYARAD D-330, SR-35;
Etc.

  Among them, those containing an ethylene oxide addition structure in the molecule, Aronix M-310 manufactured by Toagosei Co., Ltd., SR-355 manufactured by Nippon Kayaku Co., Ltd., etc. are particularly preferred because of their excellent developability in the present invention. .

  In addition to the above, the photosensitive resin composition of the present invention includes optional components as long as the purpose is not impaired, and further includes solvents, dyes, pigments, flame retardants, antioxidants, polymerization inhibitors, leveling agents, humectants, viscosity modifiers. Preservatives, antibacterial agents, antistatic agents, anti-blocking agents, ultraviolet absorbers, infrared absorbers, electromagnetic shielding agents, fillers, and the like can be added. Especially used for insulating materials (such as circuit protection films, coverlay layers, interlayer insulating materials, etc.) that are in direct contact with the circuit for electronic materials, and for members that can become high heat around the circuit (printed wiring board adhesive, support substrate, etc.) When doing so, it is preferable to use a flame retardant together.

 Examples of the flame retardant include melamine phosphate, melamine polyphosphate, guanidine phosphate, guanidine polyphosphate, ammonium phosphate, ammonium polyphosphate, ammonium amidophosphate, ammonium polyphosphate, carbamate phosphate, and carbamate polyphosphate. Phosphate compounds and polyphosphate compounds, red phosphorus, organophosphate compounds, phosphazene compounds, phosphonic acid compounds, aluminum diethylphosphinate, aluminum methylethylphosphinate, aluminum diphenylphosphinate, aluminum ethylbutylphosphinate, Phosphinic acid compounds such as aluminum methylbutylphosphinate and aluminum aluminum phosphinate, phosphine oxide compounds, phosphorane compounds, phosphoramidation Phosphorus flame retardants such as products, triazine compounds such as melamine, melam, melem, melon and melamine cyanurate, cyanuric acid compounds, isocyanuric acid compounds, triazole compounds, tetrazole compounds, diazo compounds, urea and other nitrogen flame retardants , Silicon flame retardants such as silicone compounds and silane compounds, halogenated bisphenol A, halogenated epoxy compounds, halogenated flame retardants such as halogenated oligomers and polymers, halogenated flame retardants such as halogenated phenoxy compounds, water Metal hydroxides such as aluminum oxide, magnesium hydroxide, zirconium hydroxide, barium hydroxide, calcium hydroxide, tin oxide, aluminum oxide, magnesium oxide, zirconium oxide, zinc oxide, molybdenum oxide, antimony oxide, Nickel, zinc carbonate, magnesium carbonate, calcium carbonate, barium carbonate, zinc borate, and inorganic flame retardants such as hydrated glass. In the present invention, taking into consideration the influence on the environment, which has been recently taken into consideration, it is desirable to use a non-halogen flame retardant such as a phosphorus flame retardant or a nitrogen flame retardant, and in particular, the thermosetting resin composition of the present invention. It is preferable to use a phosphazene compound, a phosphinic acid compound, melamine polyphosphate, ammonium polyphosphate, melamine cyanurate, etc., which are more effective in flame retardancy, in combination. In the present invention, these flame retardants can be used alone or in combination.

  Since the photosensitive resin composition of the present invention and its cured product are characterized by excellent alkali developability, they can be suitably used for applications in which a film forming process including photocuring, alkali development, and post-cure is used. . Furthermore, since it has excellent solder heat resistance and coating film resistance, and also has excellent flexibility and flexibility, it can be suitably used particularly for solder resist inks for flexible printed wiring boards and photosensitive coverlay films. .

  The photosensitive resin composition of the present invention can be applied to a metal, ceramics, glass, plastic, wood, slate or the like as a substrate, and is not particularly limited. Specific types of plastic include polyester, polyolefin, polycarbonate, polystyrene, polymethyl methacrylate, triacetyl cellulose resin, ABS resin, AS resin, polyamide, epoxy resin, melamine resin, and the like. Examples of the shape of the substrate include a film sheet, a plate-like panel, a lens shape, a disk shape, and a fiber shape, but are not particularly limited.

The photosensitive resin composition of the present invention can be cured by a known radiation curing method to obtain a cured product, and as active energy rays, electron beams, ultraviolet rays, and visible light of 400 to 500 nm can be used. A thermionic emission gun, a field emission gun, or the like can be used as the electron beam source to be irradiated. For example, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a metal halide lamp, a gallium lamp, a xenon lamp, a carbon arc lamp, or the like can be used as a source (light source) for ultraviolet light and visible light of 400 to 500 nm. Specifically, an ultra-high pressure mercury lamp, a xenon mercury lamp, or a metal halide lamp is often used because of the point light source and the stability of luminance. The active energy dose to be irradiated, can be set appropriately in the range of 5~2000mJ / cm ^2, it is preferably in the range on the easy of 50~1000mJ / cm ² management process. Further, these active energy rays can be used in combination with heat by infrared rays, far infrared rays, hot air, high-frequency heating or the like.

  When used as a photo solder resist, the photosensitive resin composition of the present invention can be used as a liquid resist ink dissolved in a solvent or a dry film type resist obtained by previously drying the solvent.

  When used as a liquid resist ink, the photosensitive resin composition of the present invention may be subjected to radiation curing after the solvent is volatilized by natural or forced drying after coating on the base material. Although natural or forced drying may be performed after the radiation curing, it is preferable that the radiation curing is performed after natural or forced drying. In the case of a liquid resist ink, it is preferable that the solvent does not evaporate during handling until the application to the substrate is completed, such as the storage step and the coating step. As the dilution solvent at the time of ink preparation, those having a high boiling point are preferable. For example, it is particularly preferable to use carbitol acetate, methoxypropyl acetate, cyclohexanone, diisobutyl ketone or the like. In addition, in the case of liquid resist inks, there are also two-component types that are stored in advance separately from the curing agent in consideration of storage stability and handling, and mixed with a curing agent as necessary before coating. is there. Also in the case of the present invention, at least one compound (B) selected from the group consisting of an epoxy group-containing compound, an isocyanate group-containing compound, and a blocked isocyanate group-containing compound, a photopolymerization initiator (C), and thermosetting The auxiliary agent (D) can also be used as a two-component type, for example, by storing separately from the others as necessary.

  On the other hand, when using as a dry film type resist, first, a dry film type is obtained by applying a photosensitive composition dissolved in a solvent to a film substrate having good releasability such as a separate film and then drying the solvent. Create a resist. In this case, unlike the above-described liquid resist ink, it is necessary to dry the solvent completely in a short time, and therefore a solvent having a low boiling point is preferable. For example, it is particularly preferable to use methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate, tetrahydrofuran, toluene, isopropyl alcohol, or the like. The dry film formed on the separate film is laminated on a copper circuit or the like formed on polyimide, and thereafter, bubbles and the like are removed and adhered to the circuit by lamination or vacuum lamination. After this pasting step, there may be a case where the radiation curing is performed through a separate film, or a case where the development pattern is brought into contact after the separation film is peeled to perform the radiation curing. When radiation curing is performed by bringing a development pattern into contact, if the dry film has a tack, the development pattern may be contaminated. Therefore, a dry film type resist is required to have a low dry film tack. Since the photosensitive resin composition of this invention can reduce a tack as needed, it can be usefully used also as a dry film resist.

  Furthermore, the photosensitive resin composition of the present invention forms a pattern by developing after radiation curing, and forms a film having excellent resistance by thermosetting as post-cure. The post cure is preferably 30 to 2 hours at 100 to 200 ° C. Further, in order to further improve the resistance of the coating film, an active energy ray can be irradiated as necessary after post-curing. By irradiating the active energy ray after the post cure, the solder heat resistance and the like can be further improved.

 The cured product of the photosensitive resin composition of the present invention is a substrate, for example, a resist film, an interlayer insulating material for a build-up method, or an optical waveguide as a printed circuit board, an optoelectronic circuit board or an electrical / electronic / optical component such as an optical circuit board. Used for. Specific examples of articles having these base materials include home appliances such as computers and liquid crystal displays, and portable devices such as mobile phones. The thickness of the cured product layer is about 0.5 to 160 μm, and preferably about 1 to 100 μm.

  A solder mask for a flexible printed wiring board, an interlayer insulating film for a multilayer printed wiring board, or a photosensitive optical waveguide comprising the steps of applying, photocuring, alkali treatment and heat treatment of the photosensitive resin composition of the present invention This manufacturing method is also included in the present invention. For example, when specifically explaining a flexible printed wiring board, when using the liquid resin composition described above, a screen printing method, a spray method, a roll coating method, an electrostatic coating method, a curtain coating method, etc. The photosensitive resin composition of this invention is apply | coated by the method of 0.5-160 micrometers by the method of this, and it is normally dried at the temperature of 50-110 degreeC, Preferably it is 60-100 degreeC, and forms a coating film. Thereafter, the coating film is directly or indirectly irradiated with active energy rays such as ultraviolet rays with an intensity of about 10 to 2000 mJ / cm 2 through a photomask having an exposure pattern such as a negative film, and the unexposed portion is exposed with an alkali developer. Develop by spraying, rocking dipping, brushing, scrubbing, etc., for example. If necessary, further UV irradiation is performed, and then heat treatment is usually performed at a temperature of 100 to 200 ° C., preferably 140 to 180 ° C., so that the developability is excellent, and the cured film has adhesiveness, flexibility, solder A printed wiring board having a permanent protective film satisfying various physical properties such as heat resistance, chemical resistance and electrical insulation is obtained.

  EXAMPLES The present invention will be described in more detail with reference to the following examples. However, the following examples do not limit the scope of rights of the present invention. In the examples, “part” represents “part by weight”.

  The measurement conditions for GPC are as follows.

<Measurement of weight average molecular weight (Mw)>
For measurement of Mw, GPC (gel permeation chromatography) “HPC-8020” manufactured by Tosoh Corporation was used. GPC is liquid chromatography that separates and quantifies substances dissolved in a solvent (THF; tetrahydrofuran) based on the difference in molecular size. In the measurement of the present invention, “LF-604” (manufactured by Showa Denko KK: GPC column for rapid analysis: 6 mm ID × 150 mm size) is connected in series to the column, the flow rate is 0.6 ml / min, and the column temperature is 40. It carried out on the conditions of (degreeC) and the determination of the weight average molecular weight (Mw) was performed in polystyrene conversion.

<Molecular weight distribution (Mw / Mn)>
The degree of dispersion of the molecular weight is expressed. In the present invention, the weight average molecular weight (Mw) / number average molecular weight (Mn) was determined from the molecular weight measurement result.

[Production Example 1]
Nitrogen was introduced into a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, inlet tube, thermometer, 200.4 parts of PEG # 2000 (manufactured by NOF Corporation, polyethylene glycol), anhydrous pyromerit 43.6 parts of acid, 2.44 parts of DBU as a catalyst, and 250 parts of toluene as a solvent were charged, and the mixture was heated to 110 ° C. with stirring under a nitrogen stream and reacted for 8 hours to obtain a half ester compound. Next, the nitrogen from the nitrogen introduction tube was stopped in this flask and switched to introduction of dry air. While stirring, 54.0 parts of GMA (manufactured by NOF Corporation: glycidyl methacrylate), 0.15 of hydroquinone as a polymerization inhibitor Part was added and reacted at 80 ° C. for 8 hours. Next, 36.1 parts of Ricacid SA (manufactured by Shin Nippon Rika Co., Ltd .: succinic anhydride) was added as an acid anhydride and reacted for 8 hours at 80 ° C. After confirming that the absorption of the acid anhydride group disappeared by FT-IR measurement, it was cooled to room temperature. After completion of the reaction, methyl ethyl ketone was added to this solution to adjust the solid content to 50.0%. The carboxyl group-containing photosensitive ester resin according to this design had an ethylenically unsaturated group equivalent of 880 g / eq, a polystyrene-equivalent weight average molecular weight of 21,100, and an actually measured acid value of the resin solids of 64 mgKOH / g.

[Production Examples 2 to 5]
Carboxyl group-containing photosensitive ester resins of Production Examples 2 to 5 were obtained by performing the same operations as in Production Example 1 using the raw materials shown in Table 1.

[Production Example 6]
Dry air was introduced into a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, inlet tube and thermometer, 200.4 parts of PEG # 2000 (manufactured by NOF Corporation, polyethylene glycol), NK oligo EA-1020 (Shin-Nakamura Chemical Co., Ltd., bisphenol A type epoxy acrylate) 48.5 parts, pyromellitic anhydride 43.6 parts, catalyst 2.92 parts DBU, polymerization inhibitor 0.16 parts hydroquinone, solvent As a starting material, 250 parts of MEK was charged, and the mixture was heated to 80 ° C. with stirring in a nitrogen stream and reacted for 8 hours to obtain a half ester compound. Next, 28.4 parts of GMA (manufactured by NOF Corporation: glycidyl methacrylate) was added to this solution and reacted at 80 ° C. for 8 hours. Next, 20.0 parts of Ricacid SA (manufactured by Shin Nippon Rika Co., Ltd .: succinic anhydride) was added as an acid anhydride and reacted for 8 hours at 80 ° C. After confirming that the absorption of the acid anhydride group disappeared by FT-IR measurement, it was cooled to room temperature. After completion of the reaction, methyl ethyl ketone was added to this solution to adjust the solid content to 50.0%. The carboxyl group-containing photosensitive ester resin according to this design had an ethylenically unsaturated group equivalent of 1136 g / eq, a polystyrene-equivalent weight average molecular weight of 14100, and an actually measured acid value of resin solids of 66 mgKOH / g.

[Production Examples 7 to 10]
Carboxyl group-containing photosensitive ester resins of Production Examples 7 to 10 were obtained by performing the same operations as in Production Example 6 using the raw materials shown in Table 1.

  Table 1 shows the specifications of the carboxyl group-containing photosensitive ester resin obtained in Production Examples 1 to 10.

PEG # 1000: manufactured by NOF Corporation, polyethylene glycol PEG # 2000: manufactured by NOF Corporation, polyethylene glycol PTGL-3000: manufactured by Hodogaya Chemical Co., Ltd., polytetramethylene glycol P-2010: manufactured by Kuraray Co., Ltd., poly [( 3-methyl-1,5-pentanediol) -alt- (adipic acid)]
NK Oligo EA-1020: Shin-Nakamura Chemical Co., Ltd., bisphenol A type epoxy acrylate NK Oligo EA-5224: Shin-Nakamura Chemical Co., Ltd., hexahydrophthalic acid diglycidyl ether acrylate NK Oligo EA-5520: Shin-Nakamura Chemical Manufactured by Kogyo Co., Ltd., 1,4-butanediol diglycidyl ether acrylate PMDA: pyromellitic anhydride GMA: manufactured by NOF Corporation, glycidyl methacrylate ricacid SA: manufactured by Shin Nippon Rika Co., Ltd., succinic anhydride DBU: diazabicyclo Undesen

[Production Example 11]
A four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet pipe, inlet pipe, thermometer, bisphenol A type epoxy having an epoxy equivalent of 650, a softening point of 81.1 ° C., and a melt viscosity (150 ° C.) of 12.5 poise 371 parts of resin, 925 parts of epichlorohydrin, and 463 parts of dimethyl sulfoxide were added and dissolved uniformly, and then 52.8 parts of 98.5% aqueous sodium hydroxide solution was added at 70 ° C. over 100 minutes with stirring. After the addition, the reaction was further carried out at 70 ° C. for 3 hours. Subsequently, most of the excess unreacted epichlorohydrin and dimethyl sulfoxide are distilled off under reduced pressure, the reaction product containing by-product salt and dimethyl sulfoxide is dissolved in 750 parts of methyl isobutyl ketone, and further 10 parts of 30% aqueous sodium hydroxide solution. And reacted at 70 ° C. for 1 hour. After completion of the reaction, washing was performed twice with 200 parts of water. After separation of oil and water, methyl isobutyl ketone is recovered by distillation from the oil layer, and an epoxy resin having an epoxy equivalent of 287, a hydrolyzable chlorine content of 0.07%, a softening point of 64.2 ° C., and a melt viscosity (150 ° C.) of 7.1 poise. 340 parts were obtained.

  287 parts of this epoxy resin was put into a four-necked flask equipped with another stirrer, reflux condenser, nitrogen inlet pipe, inlet pipe and thermometer, and further 72 parts of acrylic acid, 0.3 part of methylhydroquinone, cyclohexanone 194 The reaction mixture was dissolved by heating and stirring at 90 ° C. Subsequently, the reaction liquid was cooled to 60 ° C., 1.7 parts of triphenylphosphine was added, and the reaction was performed at 100 ° C. for about 32 hours in the presence of oxygen to obtain a reaction product having an actually measured acid value of 1 mgKOH / g. Next, 78 parts of succinic anhydride and 42 parts of cyclohexanone were added thereto and reacted at 95 ° C. for about 6 hours to obtain a carboxyl group-containing photosensitive resin whose main skeleton was a bisphenol A type epoxy resin. Next, cyclohexanone was added to this solution to adjust the solid content to 50.0%. The ethylenically unsaturated group equivalent of the resin solid content by this design is 450 eq / g, the weight average molecular weight in terms of polystyrene is 7400, the molecular weight distribution is 2.23, and the acid value of the resin solid content by measurement is 100 mgKOH / g. It was.

[Production Example 12]
To a four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, an inlet tube, and a thermometer, 330 parts of a cresol novolac epoxy resin having an epoxy equivalent of 218 g / eq (manufactured by Toto Kasei Co., Ltd .: YDCN-702). The mixture was melted by heating at 90 to 100 ° C. and stirred. Next, 120 parts of acrylic acid, 0.6 part of hydroquinone, and 5 parts of dimethylbenzylamine were added, and the mixture was heated to 115 ° C. with stirring in the presence of oxygen and reacted for 12 hours. Next, 400 parts of cyclohexanone was added to this flask and dissolved by heating to 70 ° C. Next, 81 parts of succinic anhydride was added, the temperature was raised to 95 ° C., and the mixture was stirred and reacted for 8 hours. After confirming that the absorption of the acid anhydride group disappeared by FT-IR measurement, the mixture was cooled to room temperature to obtain a carboxyl group-containing photosensitive resin whose main skeleton was a cresol novolak skeleton. Next, cyclohexanone was added to this solution to adjust the solid content to 50.0%. The ethylenically unsaturated group equivalent of the resin solid content by this design is 319 g / eq, the weight average molecular weight in terms of polystyrene is 11000, the molecular weight distribution is 2.90, and the acid value of the resin solid content by measurement is 85 mgKOH / g. It was.

[Production Example 13]
A dropping funnel was placed in a four-necked flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, inlet tube, and thermometer, and 400 parts of cyclohexanone was charged into the flask, and the temperature was raised to 90 ° C. with stirring in a nitrogen atmosphere. did. In a separate container, 15 parts of methacrylic acid, 30 parts of methyl methacrylate, 30 parts of butyl methacrylate, 25 parts of benzyl methacrylate, 20 parts of azobisisobutyronitrile as a polymerization initiator and 100 parts of cyclohexanone are stirred and dissolved uniformly. did. The monomer solution was charged into a dropping funnel installed in the flask, and the monomer solution in the dropping funnel was dropped into the flask over 2 hours while stirring the flask at 90 ° C. in a nitrogen atmosphere. Stirring was continued at 90 ° C. even after completion of the dropping, and 0.5 part of azobisisobutyronitrile was charged into the flask after 2 hours from the end of the dropping. After 1 hour, 0.5 part of azobisisobutyronitrile was again added to the flask, and stirring was continued for another 2 hours. Thereafter, the flask was cooled to stop the reaction. A small amount of sampling was performed to obtain a carboxyl group-containing acrylic prepolymer having a polystyrene-equivalent weight average molecular weight of 18700, a molecular weight distribution of 2.58, and an acid value of resin solid content of 98 mgKOH / g.

  Next, the nitrogen from the nitrogen introduction tube was stopped in this flask, switched to introduction of dry air, and 111 parts of glycidyl methacrylate, 6 parts of dimethylbenzylamine and 0.3 part of hydroquinone as a polymerization inhibitor were added while stirring. , Reacted at 90 ° C. for 8 hours. After completion of the reaction, a small amount of sampling was performed to obtain a hydroxyl group-containing acrylic prepolymer having a polystyrene-equivalent weight average molecular weight of 19,900, a molecular weight distribution of 2.72, and an actually measured acid value of resin solids of 5 mgKOH / g.

  Next, 63 parts of succinic anhydride was added to the flask and reacted for 6 hours with stirring at 90 ° C. in a dry air atmosphere. After confirming that absorption of the acid anhydride group disappeared by FT-IR measurement, the mixture was cooled to room temperature to obtain a carboxyl group-containing photosensitive resin whose main skeleton was an acrylic resin. Next, cyclohexanone was added to this solution to adjust the solid content to 50.0%. The ethylenically unsaturated group equivalent of the resin solid content by this design is 863 g / eq, the weight average molecular weight in terms of polystyrene is 22000, the molecular weight distribution is 2.81, and the acid value of the resin solid content by measurement is 70 mgKOH / g. It was.

[Production Example 14]
In a 4-neck flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, inlet tube, thermometer, 212 parts of PTG850 (Hodogaya Chemical Co., Ltd .: polytetramethylene glycol, hydroxyl value = 129 mgKOH / g), ethylene glycol 75 Part, pyromellitic anhydride (manufactured by Daicel Chemical Industries, Ltd.) 159 parts, dimethylbenzylamine 2 parts, cyclohexanone 375 parts as a solvent, stirred for 10 hours at 100 ° C. with stirring in a nitrogen stream, Reaction was performed. Subsequently, 54 parts of isophorone diisocyanate was added to the flask and stirred at 90 ° C. for 8 hours to carry out a urethanization reaction. After completion of the reaction, a small amount of sampling was performed to obtain a carboxyl group-containing urethane prepolymer having a polystyrene-equivalent weight average molecular weight of 15,200, a molecular weight distribution of 2.87, and an actually measured acid value of 170 mgKOH / g of resin solids.

  Next, the nitrogen from the nitrogen introduction tube was stopped in this flask, switched to introduction of dry air, 110 parts of glycidyl methacrylate, 6 parts of dimethylbenzylamine, and 0.3 part of hydroquinone as a polymerization inhibitor were added while stirring. The reaction was continued for 8 hours at 90 ° C. After cooling, a small amount of sampling was performed to obtain a carboxyl group-containing photosensitive urethane resin whose main skeleton is an acid anhydride-modified urethane skeleton. Next, cyclohexanone was added to this solution to adjust the solid content to 50.0%. The ethylenically unsaturated group equivalent of the resin solid content according to the present design was 896 g / eq, the polystyrene-equivalent weight average molecular weight was 18,800, the molecular weight distribution was 3.12, and the acid value of the resin solid content was 72 mgKOH / g as measured.

[Production Example 15]
In a 4-neck flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, inlet tube, and thermometer, 218 parts of PTG850 (Hodogaya Chemical Co., Ltd .: polytetramethylene glycol, hydroxyl value = 129 mgKOH / g), ethylene glycol 47 Part, 125 parts of pyromellitic anhydride (manufactured by Daicel Chemical Industries, Ltd.), 2 parts of dimethylbenzylamine, and 375 parts of cyclohexanone as a solvent, stirred for 10 hours at 100 ° C. with stirring in a nitrogen stream, Reaction was performed. Subsequently, 111 parts of isophorone diisocyanate was added to the flask and stirred at 90 ° C. for 8 hours to carry out a urethanization reaction. After completion of the reaction, a small amount of sampling was performed to obtain a carboxyl group-containing urethane prepolymer having a polystyrene-equivalent weight average molecular weight of 17000, a molecular weight distribution of 2.60, and an actually measured acid value of 110 mgKOH / g of resin solids.

  Next, the nitrogen from the nitrogen introduction tube was stopped in this flask and switched to introduction of dry air. While stirring, 131 parts of glycidyl methacrylate, 6 parts of dimethylbenzylamine, and 0.3 part of hydroquinone as a polymerization inhibitor were added. The reaction was continued for 8 hours at 90 ° C. After completion of the reaction, a small amount of sampling was performed to obtain a hydroxyl group-containing urethane prepolymer having a polystyrene-equivalent weight average molecular weight of 19,200, a molecular weight distribution of 3.00, and an actually measured resin solid acid value of 4 mgKOH / g.

  Next, 74 parts of succinic anhydride was added to the flask, and the reaction was further continued for 6 hours at 90 ° C. in a dry air atmosphere. After confirming that absorption of the acid anhydride group disappeared by FT-IR measurement, the mixture was cooled to room temperature to obtain a carboxyl group-containing urethane resin whose main skeleton was an acid anhydride-modified urethane resin. Next, cyclohexanone was added to this solution to adjust the solid content to 50.0%. The ethylenically unsaturated group equivalent of the resin solid content by this design is 765 g / eq, the weight average molecular weight in terms of polystyrene is 21400, the molecular weight distribution is 3.20, and the acid value of the resin solid content by measurement is 67 mgKOH / g. It was.

Table 2 summarizes the specifications of the resins obtained in Production Examples 10 to 14.

[Example 1]
With respect to 100 parts of the solid content of the carboxyl group-containing photosensitive ester resin (A) solution obtained in Production Example 1, as a compound (B), Epicoat 1031S (manufactured by Mitsubishi Chemical Corporation: polyfunctional glycidyl ether type epoxy resin) 5 parts, BL3175 (manufactured by Sumika Bayer Urethane Co., Ltd .: isocyanurate type blocked isocyanate), and Irgacure 907 (manufactured by Ciba Specialty Chemicals Co., Ltd .: 2-methyl-1- [4] as a photopolymerization initiator. -(Methylthio) phenyl] -2-morpholino-1-propane) 2.5 parts and DETX-S (Nippon Kayaku Co., Ltd .: 2,4-diethylthioxanthone) 0.25 parts were uniformly dissolved and mixed. The photosensitive resin composition of this invention was created.

[Examples 2 to 14]
About the resin varnish obtained by manufacture example 2-19, it mix | blended in the ratio similar to Example 1, and created the photosensitive resin composition containing each resin.

[Comparative Examples 1-5]
About the resin varnish obtained by manufacture examples 10-14, it mix | blended in the ratio similar to Example 1, and created the photosensitive resin composition containing each resin.

<Evaluation 1>
The following evaluation was performed about the obtained photosensitive resin composition.

[Create sample A]
The obtained photosensitive resin composition was uniformly coated on a Kapton 100H (manufactured by Toray DuPont Co., Ltd .: polyimide film (25 μm thickness)) to a dry film thickness of 20 μm and dried, and then to room temperature. Cooled down. This is designated as sample A.

[Create sample B]
The sample A was irradiated with ultraviolet rays having an integrated light quantity of 300 mJ / cm ² using an ultraviolet exposure apparatus (USHIO INC .: “UVC-2534 / 1MNLC3-AA08”, 120 W / cm metal halide lamp, 1 lamp), and then 150 It was heat-cured (post-cured) for 1 hour in a hot air dryer at 0 ° C. The obtained cured film was cooled to room temperature. This is designated as sample B.

[Create sample C]
21 steps of Step Tablets (manufactured by Kodak Co., Ltd.) were brought into intimate contact with Sample A, and irradiated with ultraviolet rays having an integrated light amount of 150 mJ / cm ² using the same ultraviolet exposure apparatus used when Sample B was prepared. This is designated as sample C.

[Create sample D]
The obtained photosensitive resin composition was uniformly coated on a 38 μm-thick polyethylene terephthalate (hereinafter also referred to as “PET”) separator film so as to have a dry film thickness of 30 μm, and then dried. Until cooled. Next, another release-treated polyester film (38 μm thick) was laminated on the adhesive layer side to obtain a sheet with a double-sided protective film. This is designated as sample D.

(1) For the touch-tack sample A, the tackiness was evaluated by finger touch as follows.
○ ・ ・ ・ No fingerprints △ ・ ・ ・ Slight fingerprints ×× Fingerprints clearly

(2) Adhesiveness According to JIS K5400, 100 pieces of 1 mm × 1 mm grids were made on the cured coating film of Sample B, and a peeling test was performed using cello tape (registered trademark). The peeled state of the grid was observed and evaluated according to the following criteria.
○: No peeling Δ: 20% or less of the grid is peeled × × 21% or more of the grid is peeled

(3) Flexibility Sample B was bent 180 degrees with the cured coating surface facing outward, and the state of the coating film at that time was evaluated according to the following criteria.
○: No cracks are observed on the film surface Δ: Slight cracks are observed on the film surface ×: The film is cracked and cracks are clearly seen on the film surface

(4) Solvent resistance Sample B is immersed in isopropyl alcohol at room temperature for 30 minutes. After confirming that there was no abnormality in the external appearance, a peeling test was performed using cello tape (registered trademark), and evaluation was performed according to the following criteria.
○ ・ ・ ・ There is no abnormality in the appearance of the coating film, and there is no blistering or peeling. Δ ・ ・ ・ Slight peeling at the end of the coating film (between the coated part and the polyimide base material). And there is peeling

(5) Acid resistance Sample B is immersed in a 10% aqueous hydrochloric acid solution at room temperature for 30 minutes. After confirming that there was no abnormality in the external appearance, a peeling test was performed using cello tape (registered trademark), and evaluation was performed according to the following criteria.
○ ・ ・ ・ There are no abnormalities in the appearance of the coating film, and there is no swelling or peeling. △ ・ ・ ・ Slight swelling or peeling is observed around the edge of the coating film (between the coated part and the polyimide substrate).・ There are swelling and peeling on the coating film.

(6) Substrate warpage Sample B was cut into a square of 5 cm x 5 cm, and the cured coating film surface was faced up and left on a flat table at 25 ° C and a humidity of 50% for 12 hours. For the sample after standing, the height at which the four corners of the square were lifted from the table was measured, the average value was calculated, and evaluated according to the following criteria. The smaller this value, the less the sample warps, indicating better.
○: 5 mm or less Δ ... 6 mm or more to 10 mm or less x ... 11 mm or more

(7) Flux resistance After a few drops of weakly active rosin flux (manufactured by Nippon Alpha Metals Co., Ltd., trade name: RM-615) was dropped on the test piece of Sample B, it was heat-treated in an oven at 260 ° C. for 3 minutes. The test piece was taken out of the oven, the flux was wiped off with isopropyl alcohol, and then judged according to the thickness of the cured film on the polyimide as follows. A thing which does not have a practical problem is (circle).
〇 ・ ・ ・ Change in film thickness is less than 5μm
Δ: Change in film thickness is 5 to 10 μm
×: Change in film thickness is greater than 10 μm

(8) Developability Sample C was developed with a 1% sodium carbonate aqueous solution at a spray pressure of ² Kg / cm ² for 60 seconds. The number of steps in which the coating film was swollen with the developer was defined as the number of swelling steps, and the number of steps in which the coating film was washed away with the developer was defined as the number of peeling steps. It can be said that the lower the number of peeling steps, the faster the development speed and the better the developability. The developability was judged according to the following criteria using the number of peeling steps.
○ ・ ・ ・ Number of peeling steps ≦ 7
Δ: number of peeling steps = 8-14
X ... number of peeling steps ≥ 15

(9) Resolution With respect to the number of swelling steps and the number of peeling steps confirmed in the evaluation of developability, a resolution step was obtained by the following formula.
[Resolution step] = [Number of peeling steps]-[Number of swelling steps]
It can be said that the smaller the resolution step, the sharper the pattern can be formed in the actual pattern forming process, and the better the resolution. Using this resolution step, the resolution was judged according to the following criteria.
○ ・ ・ ・ Resolution step ≦ 3
△ ・ ・ ・ Resolution step = 4-7
× ・ ・ ・ Resolution step ≧ 8

(10) Insulation reliability Comb pattern (conductor pattern width / space width = 50 μm / 50 μm) in which a copper circuit is formed on polyimide is printed on a 65 mm × 65 mm sheet from which the protective film of sample D has been removed. It was laminated on a circuit board at 80 ° C. and peeled off from the separator film. After irradiating ultraviolet rays with an integrated light quantity of 300 mJ / cm ² with the same ultraviolet exposure apparatus used when creating Sample B, the specimens for evaluation were prepared by thermosetting (post-cure) for 1 hour with a 150 ° C. hot air dryer. . A DC voltage of 50 V was continuously applied to the conductor circuit of this test piece for 100 hours under an atmosphere of a temperature of 130 ° C. and a relative humidity of 85%, and the insulation resistance value between the conductors after 100 hours was measured. The evaluation criteria are as follows.
○ ・ ・ ・ Insulation resistance value 10 ⁷ or more △ ・ ・ ・ Insulation resistance value 10 ⁶ or more and less than 10 ⁷ Ω × ・ ・ ・ Insulation resistance value less than 10 ⁶ Ω

<Evaluation results>
The results of Evaluation 1 are shown in Table 3.

From the result of evaluation 1, in the prior art (Comparative Examples 1 to 5), those having excellent adhesion and flexibility have poor developability and resolution, and conversely those having excellent developability and resolution have adhesion.・ It was found to be inferior in flexibility. On the other hand, the resin compositions (Examples 1 to 10) of the present invention have excellent physical properties such as adhesion, flexibility, flux resistance, developability, and resolution, as well as insulation reliability. I found it excellent. Furthermore, it has been found that it has a performance that cannot be achieved by the prior art (Comparative Examples 1 to 5), which has both the resistance of the coating film and flexible performance such as substrate warpage and flexibility. On the other hand, Example 11 cannot provide the flexibility of the coating film due to the small amount of the polyol (a) component, and Example 12 cannot obtain sufficient solder heat resistance and flexibility because the molecular weight is too small. It was. In addition, Example 13 was not able to obtain sufficient developability because the acid value was too small, and Example 14 had too few double bond equivalents, so that the number of sites functioning as photocrosslinking points decreased. It was found that desired heat resistance and coating film resistance could not be obtained.

[Example 11]
Epicoat 1031S (manufactured by Mitsubishi Chemical Corporation: polyfunctional glycidyl ether type epoxy resin) 5 as the compound (B) with respect to 100 parts of the solid content of the carboxyl group-containing photosensitive ester resin (A) solution obtained in Production Example 1 Part, BL3175 (manufactured by Sumika Bayer Urethane Co., Ltd .: isocyanurate type blocked isocyanate), Irgacure 907 (manufactured by Ciba Specialty Chemicals Co., Ltd .: 2-methyl-1- [4] as a photopolymerization initiator (C) -(Methylthio) phenyl] -2-morpholino-1-propane) 2.5 parts, also DETX-S (Nippon Kayaku Co., Ltd .: 2,4-diethylthioxanthone) 0.25 parts, containing ethylenically unsaturated group Aronix M-310 (manufactured by Toagosei Co., Ltd .: trimethylolpropane PO modified tria as a compound) 8 parts, DICY7 (manufactured by Ajinomoto Fine Techno Co., Ltd .: dicyandiamide) as an additive for thermosetting (D), 8 parts R812 (manufactured by Nippon Aerosil Co., Ltd .: hydrophobic silica fine particles), green paste (green) 2 parts of pigment / base resin (phenol resin) / solvent (carbitol acetate) = 28/12/60) and 8 parts of SPB-100 (Otsuka Chemical Co., Ltd .: phosphazene flame retardant) as a flame retardant, PHOSMEL-100 (Nissan Chemical Industry Co., Ltd .: melamine polyphosphate) 8 parts, STABIACE MC-5S (Sakai Chemical Industry Co., Ltd .: melamine cyanurate flame retardant) is blended and kneaded with 3 rolls of the present invention. A photosensitive solder resist ink was prepared.

[Examples 12 to 20]
About the resin varnish obtained by manufacture examples 2-10, it mix | blended in the ratio similar to Example 11, and created the soldering resist ink containing each resin.

[Comparative Examples 6 to 10]
About the resin varnish obtained by manufacture examples 11-15, it mix | blended in the ratio similar to Example 11, and created the soldering resist ink containing each resin.

<Evaluation 2>
The following evaluation was performed about the obtained photosensitive soldering resist ink.

[Create sample E]
The photosensitive solder resist ink obtained in Examples 15 to 28 and Comparative Examples 6 to 10 so that the film thickness after drying was 20 μm on the release surface of a 38 μm-thick separator PET film on which one side was peeled. Was coated and dried, and then cooled to room temperature. Next, the photosensitive resin composition surface on this film and a 25 μm-thick PET film are laminated to create a dry film type photosensitive solder resist of the photosensitive resin composition in which both surfaces are sandwiched by the PET film. did.

Next, from this dry film, the separator PET film is peeled off, and the photosensitive resin composition surface exposed on the surface and the copper foil surface of the copper-clad laminate (thinning the copper surface by etching) are laminated together, It was made to adhere by vacuum lamination (60 ° C., 0.2 MPa = 2 kg / cm ² ). Subsequently, a negative film having a resist pattern [φ70 μm hole, 21 steps, solid line / space = 100/60 (μm / μm)] is brought into close contact with the PET film, and an ultraviolet exposure device (EXM-1201F manufactured by ORC Corporation), short (Arc lamp) was used to irradiate ultraviolet rays (400 mJ / cm ² ). Next, the PET film was peeled off, and developed with a 1% sodium carbonate aqueous solution at a spray pressure of ² kg / cm ² for 60 seconds. Thereafter, heat curing was carried out with a hot air dryer at 150 ° C. for 1 hour to prepare Sample E.

(1) Solvent resistance Sample E was used in place of Sample B, and a solvent resistance test was conducted and evaluated in the same manner as in Evaluation 1.

(2) In place of acid-resistant sample B, sample E was used, and an acid resistance test was conducted and evaluated in the same manner as in evaluation 1.

(3) Developability Using the sample E instead of the sample C, the developability test was conducted in the same manner as in the evaluation 1, and the determination was made according to the following criteria.
○ ・ ・ ・ Number of peeling steps ≦ 5
Δ: number of peeling steps = 6 to 10
X ... number of peeling steps ≥ 11

(4) Resolution With respect to sample E, the hole part of φ70 μm was observed with a magnifying glass, and the diameter of the part where the resist layer was developed and the copper surface was exposed (the part where the hole was opened) was measured. The resolution was judged according to the following criteria. It can be said that the closer the diameter of this hole is to 70 μm, the more faithfully the pattern is formed and the better the resolution.
○ ・ ・ ・ Diameter 60μm or more Δ ・ ・ ・ Diameter 40μm or more to 59μm or less × ・ ・ ・ Diameter 39μm or less

(5) Solder heat resistance A weakly active rosin-based flux (manufactured by Nippon Alpha Metals Co., Ltd., trade name: RM-615) was applied to Sample E, and immersed in a solder bath (JIS C 6481) at 260 ° C. for 10 seconds. This was repeated as 2 cycles, and the state of the coating film was determined as follows.
○… There is no abnormality in the appearance of the coating film, and there is no swelling or peeling.
Δ: The coating film is partially swollen or peeled off.
X: The whole coating film has swelling or peeling.

[Create sample F]
After the photosensitive solder resist inks obtained in Examples 15 to 28 and Comparative Examples 6 to 10 were uniformly coated on a 38 μm-thick separator PET film so that the dry film thickness was 20 μm and dried, Cooled to room temperature. Next, after irradiating ultraviolet rays with an integrated light amount of 400 mJ / cm ² with the same ultraviolet exposure apparatus used when creating Sample E in Evaluation 2, it was cured with a hot air dryer at 150 ° C. for 1 hour. The obtained cured film was cooled to room temperature, and the cured coating film was peeled off from the separator film. This is designated as sample F.

(6) Flexibility In the same manner as the evaluation of the flexibility in evaluation 1, the flexibility of the sample F was tested and evaluated.

[Create sample G]
The photosensitive solder resist inks obtained in Examples 15 to 28 and Comparative Examples 6 to 10 containing a flame retardant were irradiated with ultraviolet rays without using a negative film having a resist pattern in the preparation process of Sample E (entire surface) Sample G was created in the same manner as the creation of sample E except for the exposure.

(7) Flame-retardant evaluation About the sample G, flame-retardant evaluation was performed based on UL Subject94V method, and the result was judged on the following reference | standard.
○ ・ ・ ・ VTM-0
△ ・ ・ ・ VTM-1
× ・ ・ ・ VTM-2 or less (including complete combustion)

<Evaluation results>
The results of Evaluation 2 are shown in Table 4.

  As can be seen from the results in Table 4, in Comparative Examples 6 and 7 (prior art), the coating film resistance, developability and heat resistance are excellent, but the most important as a flexible insulating protective film used for flexible printed wiring boards and the like. The flexibility, which is a physical property, could not be satisfied. In Comparative Examples 8 to 10 (prior art), the coating film resistance and developability were inferior in place of excellent flexibility. On the other hand, the photosensitive resin composition of the present invention was able to satisfy all of these physical properties essential as a flexible insulating protective layer at a high level. In addition, by adding a flame retardant, the physical properties of the conventional technique as a whole are reduced, but the photosensitive resin composition of the present invention can achieve both flame retardancy and physical properties as other resists. did it.

  As described above, the carboxyl group-containing photosensitive ester resin of the present invention has a photosensitive group and a carboxyl group in the side chain, thereby exhibiting very excellent developability even when the amount of the carboxyl group is small, Since these side chain functional groups are rich in reactivity as compared with the case where they are directly connected to the main chain, they can exhibit excellent resolution and coating film resistance. For this reason, by having a highly reactive photosensitive group and carboxyl group in the side chain, even if there are factors that significantly impair the developability and photosensitivity such as flame retardants, very good developability In addition, it exhibits photosensitivity and can exhibit flame retardancy while maintaining resolution and coating film resistance. In particular, the carboxyl group-containing photosensitive ester resin of the present invention having no urethane bond in the main chain is particularly stable when compared with Comparative Examples 9 and 10 that are urethane main skeletons because the main chain is chemically stable. It has the characteristics that it can exhibit adhesiveness and flexibility while maintaining excellent film resistance and heat resistance.

Claims (9)

Photosensitive resin containing at least one compound (B) selected from a carboxyl group-containing photosensitive ester resin (A), an epoxy group-containing compound, an unblocked isocyanate compound, and a blocked isocyanate compound, and a photopolymerization initiator (C) A composition comprising:
The carboxyl group-containing photosensitive ester resin (A) is
Reacting the polyol compound (a) with the tetrabasic acid dianhydride (b) to produce a half ester compound (c);
Reacting the half ester compound (c) with a compound (d) having an epoxy group or oxetane group and an ethylenically unsaturated group to produce a hydroxyl group-containing photosensitive ester resin (e);
A photosensitive resin composition obtained by reacting the hydroxyl group-containing photosensitive ester resin (e) with a dibasic acid anhydride (f).  Furthermore, the photosensitive resin composition of Claim 1 containing the thermosetting adjuvant (D) of an amino resin, a phenol resin, a polycarbodiimide compound, an aziridine compound, a benzoxazine compound, and a maleimide compound.   The photosensitive resin composition according to claim 1 or 2, wherein the carboxyl group-containing photosensitive ester resin (A) has an acid value of 10 to 200 mgKOH / g.  The photosensitive resin composition according to any one of claims 1 to 3, wherein the carboxyl group-containing photosensitive ester resin (A) has an ethylenically unsaturated group equivalent of 200 to 3000 g / eq.  The photosensitive resin composition according to any one of claims 1 to 4, wherein the carboxyl group-containing photosensitive ester resin (A) has a weight average molecular weight of 3000 to 100,000.  Hardened | cured material formed by hardening | curing the photosensitive resin composition in any one of Claims 1-5.  The photosensitive soldering resist ink containing the photosensitive resin composition in any one of Claims 1-6, and a flame retardant.  A dry film type photosensitive solder resist comprising the photosensitive resin composition according to claim 1 and a flame retardant. A first step of reacting the polyol compound (a) with the tetrabasic acid dianhydride (b) to obtain a half ester compound (c);
A second step of obtaining a hydroxyl group-containing photosensitive ester resin (e) by reacting the half ester compound (c) with a compound (d) having an epoxy group or oxetane group and an ethylenically unsaturated group;
The method comprises a third step of reacting the hydroxyl group-containing photosensitive ester resin (e) with a dibasic acid anhydride (f) to obtain a carboxyl group-containing photosensitive ester resin (A). A method for producing a group-containing photosensitive ester resin.