TW201704385A - White active energy ray curable resin composition - Google Patents

Abstract

An object of the present application is to provide a white active energy ray curable resin composition, which can form a cured product after a photocuring step, and has basic characteristics such as solder heat resistance, adhesion and coating film hardness, even without a further thermosetting step. The present application provides a white line active energy ray curable resin composition, comprising a reactive polycarboxylic acid compound (A), a reactive compound (B) other than the (A), a photopolymerization iniciator (C), and titanium oxide (D), wherein the reactive polycarboxylic acid compound (A) is obtained from a reaction of a reactant (E) with a polybasic acid anhydride (d), and the reactant (E) contains an epoxy resin (a) represented by the general formula (1), an acrylic acid (b), and a compound (c) having at least two or more hydroxyl groups and one or more carboxyl in one molecule.

Description

White active energy ray-hardening resin composition

The present invention relates to an active energy ray-curable resin composition suitable for a coating material for coating a conductor circuit pattern formed on a substrate such as a printed wiring board, and a cured product obtained by curing the active energy ray-curable resin composition. The coated printed wiring board or the like is coated to form a product.

The printed wiring board is generally used to form a pattern of a conductor circuit on a substrate, and to mount an electronic component by soldering on a land of the circuit pattern. The circuit portion other than the land is covered with a solder mask as a permanent protective film. Thereby, when the electronic component is soldered on the printed wiring board, the solder is prevented from adhering to an unnecessary portion, and the circuit conductor is prevented from being directly exposed to the air to be oxidized and corroded by humidity.

In the past, when a solder resist film having basic properties such as solder heat resistance and coating film hardness is formed on a printed wiring board, as described in Patent Document 1, a photo-curing step and a heat-curing step are required. First, the active energy ray-curable resin composition is applied to a printed wiring board, and then preliminarily dried at a temperature of about 60 to 100 ° C as necessary to form a coating film. Next, a pattern having a light transmissive property other than the land having the circuit pattern is used. A negative film is adhered to the active energy ray-curable resin composition, and is irradiated with an active energy ray (for example, ultraviolet ray) to harden the light. Further, the non-exposed area is removed with a weakly alkaline aqueous solution to develop the coating film. Finally, the coating film is thermally cured at a temperature of about 140 to 180 ° C, and a cured coating film of the active energy ray-curable resin composition is formed on the printed wiring board.

However, in such a conventional solder resist film forming method, since the photo-curing step and the heat-hardening step are performed, there is a problem that the productivity of the film-formed product is not improved. Moreover, when a solder resist film is formed on a substrate having low heat resistance, there is a problem that the quality of the substrate is deteriorated due to heat of the heat hardening step.

In Patent Document 2, it is disclosed that a resin composition containing a polyvalent carboxylic acid containing an unsaturated group is applied to a solder resist. However, a white active energy ray-curable resin composition in which titanium oxide or the like is dispersed is not described at all.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2008-257044

[Patent Document 2] Japanese Patent No. 2704661

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a white active energy ray-curable resin composition. After the photohardening step, a cured product having basic properties such as solder heat resistance, adhesion, and coating film hardness can be formed without further performing a heat curing step.

The present inventors have intensively studied in order to solve the above problems, and as a result, it has been found that a resin composition having a specific compound and composition can solve the above problems, and the present invention has been completed.

That is, the present invention relates to the following (1) to (8):

(1) A white active energy ray-curable resin composition containing a reactive polycarboxylic acid compound (A), a reactive polyvalent carboxylic acid compound (A), a reactive compound (B), and a photopolymerization initiator (C) and titanium oxide (D), wherein the reactive polycarboxylic acid compound (A) is obtained by reacting a reactant (E) with a polybasic acid anhydride (d), and the reactant (E) is a formula (E) 1) The epoxy resin (a) shown and at least one of the compound (b) having one or more polymerizable ethylenically unsaturated groups and one or more carboxyl groups in one molecule and one of the molecules as needed A reactant of the above hydroxyl group and one or more carboxyl group compounds (c).

(where n represents a positive number from 0 to 2)

(2) The white active energy ray-curable resin composition according to the above (1), wherein the reactive polycarboxylic acid compound (A) is obtained by reacting a reactant (E) with a polybasic acid anhydride (d). The reactant (E) is an epoxy resin (a) represented by the formula (1) and a compound (b) having one or more polymerizable ethylenically unsaturated groups and one or more carboxyl groups in one molecule. A reactant of a compound (c) having at least two hydroxyl groups and one or more carboxyl groups in one molecule.

(3) The white active energy ray-curable resin composition according to the above (1) or (2), wherein the photopolymerization initiator (C) is a mercaptophosphine-based photopolymerization initiator and a benzamidine group. The oxime-based photopolymerization initiator is used in an amount of from 2 to 100 parts by mass based on 1 part by mass of the benzamidine-based photopolymerization initiator.

(4) A white active energy ray-curable resin composition according to the above (1) or (2), wherein the photopolymerization initiator (C) is a mercaptophosphine-based photopolymerization initiator and a benzamidine group. The oxime-based photopolymerization initiator is used in an amount of from 3 to 50 parts by mass based on 1 part by mass of the fluorenyl fluorene-based photopolymerization initiator.

(5) A composition of a white active energy ray-curable resin according to the above (1) or (2) The photopolymerization initiator (C) is a mercaptophosphine-based photopolymerization initiator and a benzamidine-based photopolymerization initiator, the ratio of which is relative to the benzamidine-based photopolymerization. The amount of the starting agent is 1 part by mass, and the mercaptophosphine-based photopolymerization initiator is 4 to 10 parts by mass.

The white active energy ray-curable resin composition according to any one of the above aspects, wherein the mercaptophosphine-based photopolymerization initiator is selected from the group consisting of 2, 4, 6-three Methyl benzhydryl-diphenyl-phosphine oxide, bis(2,4,6-trimethylbenzylidene)-phenylphosphine oxide, bis(2,6-dimethylbenzylidene) One or more groups of -2,4,4-trimethyl-pentylphosphine oxide and (2,4,6-trimethylbenzylidene)ethoxyphenylphosphine oxide, benzamidine The fluorene photopolymerization initiator is selected from the group consisting of 1,2-octanedione, 1-[4-(phenylthio)-2-(O-benzylidenehydrazide)], 2-propanedione- One or more groups consisting of 2-O-benzimidoxime and 1-phenyl-1,2-propanedione-2-O-benzoguanidinium.

(7) A cured product of the white active energy ray-curable resin composition according to any one of the above (1) to (6).

(8) A cured wiring film comprising the white active energy ray-curable resin composition according to any one of the above (1) to (6).

According to the aspect of the present invention, by disposing the reactive polycarboxylic acid compound (A), even after the photohardening step by exposure, the thermal curing step is not performed, that is, by exposure treatment using an active energy ray. Available in reflectivity, solder heat resistance, adhesion and film hardness And many other hardened materials with excellent properties. Further, in the aspect of the invention, even if the heat hardening step is not performed after the photohardening step, the cured product excellent in the above various characteristics can be obtained, so that the production efficiency of the article (for example, a printed wiring board having a hardened film) is improved. .

Hereinafter, the present invention will be described in detail.

In the present invention, the reactive polycarboxylic acid compound (A) is obtained by reacting a reactant (E) with a polybasic acid anhydride (d), and the reactant (E) is an epoxy resin represented by the general formula (1). (a) a compound (b) having one or more polymerizable ethylenically unsaturated groups and one or more carboxyl groups in one molecule, and one or more of the molecules having at least two or more hydroxyl groups and one or more carboxyl groups The reactant of the compound (c).

That is, the reactive polycarboxylic acid compound (A) of the present invention is obtained by reacting the epoxy resin (a) with the reactant (E) of the compound (b) with the polybasic acid anhydride (d), or by epoxy resin ( a) The reaction product (E) with the compound (b) and the compound (c) is further reacted with the polybasic acid anhydride (d).

In the present invention, an ethylenically unsaturated group and a hydroxyl group are introduced into a molecular chain by an epoxy group carboxylic acid esterification reaction, and the characteristics of the present invention are exerted.

The epoxy resin (a) represented by the formula (1) of the present invention is (4(4,1,1-bis(p-hydroxyphenyl)-ethyl)α,α-dimethylbenzyl) Phenol) (hereinafter referred to as phenol compound (PA1)) is obtained by reacting with an epihalohydrin. The epoxy resin of the present invention is as shown in the following representative structure.

(where n represents a positive number from 0 to 2)

The epoxy resin of the present invention can be obtained by, for example, TECMO REVG3101L (manufactured by Printec), NC-6300C (manufactured by Nippon Kasei Co., Ltd.), and NC-6300H (manufactured by Nippon Kayaku Co., Ltd.), but can also be obtained by the following manufacturing methods. a compound of formula (1).

Further, the epoxy resin (a) used in the present invention is more preferably a solid at normal temperature. In the present invention, an epoxy resin (a) having a softening point of 50 to 100 ° C or a melting point of 50 to 190 ° C is usually used, preferably having a softening point of 60 to 100 ° C or a melting point of 60 to 190 ° C. Further, in the present invention, an epoxy equivalent of from 130 to 500 g/eq., preferably from 150 to 400 g/eq., more preferably from 170 to 300 g/eq., can be used. When the epoxy equivalent is too small, the tendency to become hard and become brittle is strong, and when the epoxy equivalent is too large, hardness is hard to be formed and the glass transition point is lowered.

Examples of the epihalohydrin used in the reaction of the phenol compound (PA1) with an epihalohydrin include epichlorohydrin, α-methylepichlorohydrin, γ-methylepichlorohydrin, and epibromohydrin. In the invention, epichlorohydrin which is industrially easy to obtain is preferred. The epihalohydrin is used in an amount of 1 mol with respect to the hydroxyl group of the phenol compound (PA1), and is usually 2 to 15 mol, preferably 4 to 10 mol. use In the case of an excessive amount of epihalohydrin, not only the productivity is poor, but also the softening point of the epoxy resin to be produced is low, which does not have a beneficial effect on the viscosity at the time of making a prepreg. Further, when the amount of epihalohydrin is less than 2 mol, the value of n becomes large, and it becomes easy to be saponified during production.

In the above epoxidation reaction, an alkali metal hydroxide is preferably used. Examples of the alkali metal hydroxide include sodium hydroxide, potassium hydroxide and the like. Further, as the alkali metal hydroxide, a solid matter may be used, and an aqueous solution thereof may also be used. For example, when an alkali metal hydroxide is used in the form of an aqueous solution, water can be continuously added to the reaction system by continuously adding an aqueous solution of an alkali metal hydroxide to the reaction system under reduced pressure or under normal pressure. The epoxidation reaction is carried out by distilling off the epihalohydrin and further separating the liquid and removing the water to continuously return the epihalohydrin to the reaction system. Further, when a solid form is used, it is preferable to use a sheet material from the viewpoints of ease of handling, solubility, and the like. The alkali metal hydroxide is used in an amount of from 1 to 0.9 moles, preferably from 1.01 to 1.25 moles, more preferably from 1.01 to 1.15 moles, per mole of the hydroxyl group of the phenol compound (PA1).

In the above epoxidation reaction, in order to promote the reaction, a tetra-ammonium salt such as tetramethylammonium chloride, tetramethylammonium bromide or trimethylbenzylammonium chloride may be used, or tetramethylguanidine chloride may be used. A quaternary phosphonium salt such as tetramethylguanidinium bromide, trimethylbenzylhydrazine chloride, triphenylbenzylhydrazine chloride or triphenylethylphosphonium bromide is added as a catalyst. These 4-stage salts are used in an amount of from 1 to 15 g, preferably from 0.2 to 10 g, per 1 mol of the hydroxyl group of the phenol compound (PA1).

In the above epoxidation reaction, in terms of reaction progress, an alcohol such as methanol, ethanol or isopropyl, tetrahydrofuran or the like is added. It is preferred to carry out the reaction, such as an ether such as an alkane, an aprotic polar solvent such as dimethylhydrazine, dimethyl hydrazine or dimethylimidazolidone, and the like, particularly in terms of optical properties thereof, in the present invention. Alcohols and/or ethers are preferred.

When the above alcohol or ether is used, it is usually used in an amount of from 2 to 50% by mass, preferably from 4 to 20% by mass, based on the amount of the epihalohydrin used. On the other hand, when the above aprotic polar solvent is used, it is usually used in an amount of 5 to 100% by mass, preferably 10 to 80% by mass based on the amount of the epihalohydrin used.

In the above epoxidation reaction, the reaction temperature is usually from 30 to 90 ° C, preferably from 35 to 80 ° C. On the other hand, the reaction time is usually from 0.5 to 10 hours, preferably from 1 to 8 hours. The reaction of the present invention may be carried out under normal pressure or reduced pressure, and it is also possible to carry out the reaction under a reduced pressure condition under azeotropic dehydration conditions of water-epihalohydrin. The reactant of the epoxidation reaction can be purified by removing epihalohydrin, a solvent or the like under heating and reduced pressure after washing with water or without washing. Further, in order to form an epoxy resin having less hydrolyzable halogen, it is preferred to dissolve the recovered reactant in a solvent such as toluene or methyl isobutyl ketone, and to add an alkali metal such as sodium hydroxide or potassium hydroxide. The aqueous solution of the hydroxide is subjected to a ring closure reaction of the by-product to make the ring closure of the halogenated alcohol belonging to the by-product more reliable.

At this time, the alkali metal hydroxide is used in an amount of usually 0.01 to 0.3 mol, preferably 0.05 to 0.2 mol, based on the hydroxyl group of the phenol compound (PA1) used in the epoxidation. Further, the reaction temperature is usually from 50 to 120 ° C, and the reaction time is usually from 0.5 to 2 hours.

In the epoxidation reaction, after the completion of the reaction, the produced salt is removed by filtration, washing with water, or the like, and then the solvent is distilled off under heating and reduced pressure to obtain an epoxy resin which can be used in the present invention. The epoxy resin obtained in such a manner also includes a part in which an epoxy resin is added by a solvent or water, or a halogen is not completely closed and a halogen remains.

The epoxy resin (a) which is a reaction product of a phenol compound (PA1) and an epihalohydrin obtained in such a manner is preferably excellent in productivity and handleability, and further satisfies any of the following to impart high mechanical strength to the cured product. Subject condition.

1. The epoxy equivalent is preferably from 195 to 245 g/eq., more preferably from 200 to 240 g/eq.

2. In the gel permeation chromatograph, the phenolic compound (PA1) is connected to each other by epihalohydrin, and the two are 30% by area or less, and the three are connected to 20% by area or less, more preferably 2 The number of individuals is 25 area% or less, and the number of connections is 3 area% or less. The remainder is the monomer of epoxy resin (a).

In the present invention, the compound (b) having one or more polymerizable ethylenically unsaturated groups and one or more carboxyl groups in one molecule is used to provide reactivity to the active energy ray. The ethylenically unsaturated group and the carboxyl group are not limited as long as they have one or more groups in the molecule. These may be mentioned as a monocarboxylic acid compound or a polyvalent carboxylic acid compound.

The monocarboxylic acid compound having one carboxyl group in one molecule may, for example, be (meth)acrylic acid or crotonic acid, α-cyanocinnamic acid, cinnamic acid, or a saturated or unsaturated dibasic acid and an unsaturated group. The reactant of the monoglycidyl compound. In the above, examples of the (meth)acrylic acid include (meth)acrylic acid, β-styrylacrylic acid, β-mercaptoacrylic acid, and (methyl). An acrylic acid dimer, a half ester of a molar reactant such as a saturated or unsaturated dibasic acid anhydride and a (meth)acrylic acid derivative having one hydroxyl group in one molecule, as a saturated or unsaturated dibasic acid and A half ester of a molar reactant such as an acrylic monoglycidyl ester derivative.

Further, a polycarboxylic acid compound having two or more carboxyl groups in one molecule may, for example, be a molar reaction of a saturated or unsaturated dibasic acid anhydride with a (meth) acrylate derivative having a plurality of hydroxyl groups in one molecule. a half ester of a substance, a half ester of a molar reactant such as a saturated or unsaturated dibasic acid and a glycidyl (meth)acrylate derivative having a plurality of epoxy groups.

Among these, in terms of sensitivity in forming an active energy ray-curable resin composition, the most preferable ones are (meth)acrylic acid; a reaction product of (meth)acrylic acid and ε-caprolactone. Or cinnamic acid. The compound (b) is preferably one which does not have a hydroxyl group in the compound.

In the present invention, the compound (c) having at least two or more hydroxyl groups and one or more carboxyl groups in one of the molecules used as needed is a reaction for the purpose of introducing a hydroxyl group into the carboxylate compound.

In the present invention, specific examples of the compound (c) having at least two or more hydroxyl groups and one or more carboxyl groups in one molecule include dimethylolpropionic acid, dimethylolbutanoic acid, and dimethylol group. A monocarboxylic acid containing a polyvalent hydroxyl group such as acetic acid, dimethylol valeric acid or dihydroxymethylhexanoic acid. As a particularly preferable one, dimethylolpropionic acid etc. are mentioned.

Among these, when considering the stability of the reaction of the epoxy resin (a) with the compound (b) and the compound (c), the compound (b) and the compound (c) The monocarboxylic acid is preferably a combination of a monocarboxylic acid and a polycarboxylic acid, and the total amount of the monocarboxylic acid and the total amount of the polycarboxylic acid are preferably 15 or more.

In the reaction, the addition ratio of the total of the carboxylic acid of the epoxy resin (a) to the compound (b) and, if necessary, the compound (c), is appropriately changed depending on the use. In other words, when all the epoxy groups are carboxylic acid esterified, since the unreacted epoxy group does not remain, the storage stability of the reactive epoxy carboxylic acid ester compound is high. At this time, only the reactivity due to the introduced double bond is utilized.

On the other hand, by deliberately reducing the amount of the carboxylic acid compound added and leaving the unreacted residual epoxy group, the reactivity due to the introduced unsaturated bond and the residual epoxy can be utilized in combination. The reaction caused by the group, for example, a polymerization reaction and a thermal polymerization reaction by a photocationic catalyst. However, at this time, attention should be paid to reviewing the storage and production conditions of the reactive epoxy carboxylic acid ester compound (E).

When the reactive epoxy carboxylic acid ester compound (E) which does not retain an epoxy group is produced, the total of the compound (b) and the compound (c) used as needed is 1 equivalent to the epoxy resin (a). It is preferably from 90 to 120 equivalent%. As long as it is within this range, it can be manufactured under relatively stable conditions. When the total amount of the compound (b) and the compound (c) to be used as required is more than the above range, the excess of the compound (b) and the compound (c) remains, which is not preferable.

Further, when the epoxy group is deliberately left, the total of the compound (b) and, if necessary, the compound (c) is preferably 20 to 90 equivalent % based on 1 equivalent of the epoxy resin (a). If it is outside this range, it will not Further, the reaction caused by the epoxy group is sufficiently carried out. At this time, it is necessary to sufficiently pay attention to the saponification during the reaction and the stability of the reactive epoxy carboxylic acid ester compound (E).

The ratio of use of the compound (b) to the compound (c) is, relative to the molar ratio of the carboxylic acid, the compound (b): the compound (c) is 95:5 to 5:95, and then preferably 95:5 to 40:60 range. As long as it is in this range, the sensitivity to the active energy ray is good, and a sufficient hydroxyl group can be introduced to react the reactive epoxy carboxylic acid ester compound (E) with the polybasic acid anhydride (d).

The carboxylic acid esterification reaction can be carried out without a solvent, or can be carried out by diluting with a solvent. Here, the solvent which can be used is not particularly limited as long as it is a solvent inert to the carboxylic acid esterification reaction.

The amount of the solvent to be used is preferably adjusted depending on the viscosity or use of the obtained resin, but it is preferably from 90 to 30 parts by mass, more preferably from 80 to 50 parts by mass, per 100 parts by mass of the solid part. Way to use.

Specific examples thereof include aromatic hydrocarbon solvents such as toluene, xylene, ethylbenzene, and tetramethylbenzene; aliphatic hydrocarbon solvents such as hexane, octane, and decane; and the like. Petroleum ether, white gasoline, solvent naphtha, etc., ester solvent, ether solvent, ketone solvent, and the like.

Examples of the ester solvent include alkyl acetates such as ethyl acetate, propyl acetate, and butyl acetate; cyclic esters such as γ-butyrolactone; ethylene glycol monomethyl ether acetate; and diethylene glycol. Monomethyl ether monoacetate, diethylene glycol monoethyl ether monoacetate, triethylene glycol monoethyl ether monoacetate, diethylene Mono- or polyalkylene glycol monoalkyl ether monoacetate such as alcohol monobutyl ether monoacetate, propylene glycol monomethyl ether acetate, butanediol monomethyl ether acetate; glutaric acid dioxane A polyvalent alkyl carboxylate such as a base ester, a dialkyl succinate or a dialkyl adipate.

Examples of the ether solvent include alkyl ethers such as diethyl ether and ethyl butyl ether; ethylene glycol dimethyl ether, ethylene glycol diethyl ether, dipropylene glycol dimethyl ether, and dipropylene glycol diethyl ether. a glycol ether such as ether, triethylene glycol dimethyl ether or triethylene glycol diethyl ether; or a cyclic ether such as tetrahydrofuran.

Examples of the ketone solvent include acetone, methyl ethyl ketone, methyl propyl ketone, methyl isobutyl ketone, cyclohexanone, and isophorone.

In addition, it can also be carried out in a single or mixed organic solvent such as the other reactive compound (B) to be described later. In this case, when it is used as a curable composition, it can be used as a composition as it is, and it is preferable.

In order to promote the reaction during the reaction, it is preferred to use a catalyst, and the amount of the catalyst used is relative to the reactant (that is, the epoxy resin (a), the carboxylic acid compound (b), and the compound (c) used as needed. The total amount of the reactants, such as a solvent added as the case may be, is usually 0.1 to 10 parts by mass. The reaction temperature at this time is usually from 60 to 150 ° C, and the reaction time is preferably from 5 to 60 hours. Specific examples of the catalyst which can be used include, for example, triethylamine, benzyldimethylamine, triethylammonium chloride, benzyltrimethylammonium bromide, and benzyltrimethyl iodide. Known general alkaline catalysts such as ammonium amide, triphenylphosphine, triphenylphosphonium hydride, methyltriphenylhydrogen hydride, chromium octoate, and zirconium octylate.

In addition, the thermal polymerization inhibitor uses hydroquinone monomethyl Ether, 2-methylhydroquinone, hydroquinone, diphenylpicrylhydrazine, diphenylamine, 3,5-di-t-butyl-4-hydroxytoluene or the like is preferred.

This reaction is based on the appropriate sampling, the acid value of the sample reaches 5mg. Below KOH/g, preferably 3 mg. The time point when KOH/g or less is used as the end point.

The preferred molecular weight range of the reactive epoxy oxy carboxylate compound (E) thus obtained is a polystyrene-equivalent weight average molecular weight measured by GPC of from 1,000 to 50,000, more preferably from 2,000 to 30,000.

When the molecular weight is less than this, the toughness of the cured product is not sufficiently exerted, and when it is larger than this, the viscosity becomes high and the coating is difficult to be formed.

Next, the acid addition step will be described in detail. The acid addition step is carried out for the purpose of introducing a carboxyl group into the reactive epoxy carboxylic acid ester compound (E) obtained in the previous step and obtaining the reactive polycarboxylic acid compound (A). In other words, the hydroxyl group generated by the carboxylic acid esterification reaction is subjected to an addition reaction with the polybasic acid anhydride (d), whereby a carboxyl group is introduced via an ester bond.

Specific examples of the polybasic acid anhydride (d) include, for example, a compound having an acid anhydride structure in a molecule, and are preferably succinic anhydride or phthalic anhydride excellent in alkali aqueous solution developability, heat resistance, and hydrolysis resistance. , tetrahydrophthalic anhydride, hexahydrophthalic anhydride, itaconic anhydride, 3-methyl-tetrahydrophthalic anhydride, 4-methyl-hexahydrophthalic anhydride, trimellitic acid Anhydride or maleic anhydride.

The reaction of adding the polybasic acid anhydride (d) can be carried out by the aforementioned The polycarboxylic acid anhydride (d) is added to the carboxylic acid esterification reaction liquid. The amount added should be changed as appropriate.

When the amount of the polybasic acid anhydride (d) to be added is, for example, when the reactive polycarboxylic acid compound (A) of the present invention is to be used as a basic development type photoresist, it is preferred to obtain the finally obtained reactive polycarboxylic acid compound. The solid acid value of (A) (according to JIS K5601-2-1:1999) is 40 to 120 mg. KOH / g, more preferably 60 to 120 mg. The polybasic acid anhydride (d) is added in such a manner as to calculate the KOH/g. When the solid acid value at this time is in this range, the photosensitive aqueous solution of the photosensitive resin composition of the present invention exhibits good developability. That is, the management of good patterning and over-exposure is also wide, and excess acid anhydride does not remain.

In order to promote the reaction during the reaction, it is preferred to use a catalyst, and the amount of the catalyst used is relative to the reactant (that is, the epoxy compound (a), the carboxylic acid compound (b), and the compound to be used as needed (c). The total amount of the obtained reactive epoxy carboxylic acid ester compound (E) and the polybasic acid anhydride (d), and a solvent to be added as the case may be 100 parts by mass, usually 0.1 to 10 parts by mass. The reaction temperature at this time is usually from 60 to 150 ° C, and the reaction time is preferably from 5 to 60 hours. Specific examples of the catalyst which can be used include, for example, triethylamine, benzyldimethylamine, triethylammonium chloride, benzyltrimethylammonium bromide, and benzyltrimethyl iodide. Alkyl ammonium, triphenylphosphine, triphenylhydroquinone, methyltriphenylhydrogen hydride, chromium octoate, zirconium octoate, and the like.

The acid addition reaction of the present invention can be carried out without a solvent, or can be carried out by diluting with a solvent. Here, the solvent which can be used is not particularly limited as long as it is an inert solvent for the acid addition reaction. set. Further, when it is produced by using a solvent in the carboxylic acid esterification reaction as the preceding step, the acid addition reaction can be directly supplied to the subsequent step without removing the solvent on the condition that the reaction is inert. The solvent which can be used is the same as that which can be used by the user in the esterification reaction of the carboxylic acid.

The amount of the solvent to be used is preferably adjusted depending on the viscosity or use of the obtained resin, but it is preferably 90 to 30 parts by mass, more preferably 80 to 50 parts by mass, per 100 parts by mass of the solid portion. The way to use.

In addition, it can also be carried out in a single or mixed organic solvent such as the reactive compound (B) to be described later. In this case, when it is used in the form of a curable composition, it is preferably used as a composition.

Further, a thermal polymerization inhibitor or the like is preferably used in the same manner as listed in the above-mentioned carboxylic acid esterification reaction.

In the case of performing the appropriate sampling, the reaction is based on the point that the acid value of the reactant is within a range of plus or minus 10% of the set acid value.

The preferred molecular weight range of the reactive polycarboxylic acid compound (A) is a polystyrene-equivalent weight average molecular weight measured by GPC of from 500 to 50,000, more preferably from 1,000 to 20,000.

The use ratio of the reactive polycarboxylic acid compound (A) in the resin composition is from 5 to 70% by mass, preferably from 10 to 65% by mass.

The reactive compound (B) which can be used in the present invention includes so-called radical-reactive acrylates, cationically reactive other epoxy compounds, and vinyl compounds which induce the two. Reactive oligomers.

Examples of the radical-reactive acrylates include monofunctional (meth) acrylates, bifunctional (meth) acrylates, trifunctional or higher (meth) acrylates, and urethanes (methyl groups). ) urethane (meth) acrylate oligomer, polyester (meth) acrylate oligomer, epoxy (meth) acrylate oligomer, and the like.

The monofunctional (meth) acrylate may, for example, be acryloylmorpholine; 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, or (meth)acrylic acid 4 Hydroxy-containing (meth) acrylate such as hydroxybutyl ester; cyclohexane-1,4-dimethanol mono(meth) acrylate, tetrahydrofurfuryl (meth) acrylate, isophthalic acid (meth) acrylate An aliphatic (meth) acrylate such as ester, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate or dicyclopentenyloxyethyl (meth) acrylate; Phenyloxyethyl acrylate, phenyl (poly)ethoxy (meth) acrylate, p-cumyl phenoxyethyl (meth) acrylate, tribromophenyloxy (meth) acrylate Ester, phenylthioethyl (meth)acrylate, 2-hydroxy-3-phenyloxypropyl (meth)acrylate, phenylphenol (poly)ethoxy (meth) acrylate, phenyl An aromatic (meth) acrylate such as a phenol epoxy (meth) acrylate.

Examples of the bifunctional (meth) acrylate include 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, and 1,9-nonanediol II. (Meth) acrylate, tricyclodecane dimethanol (meth) acrylate, bisphenol A (poly) ethoxy di(meth) acrylate, bisphenol A (poly) propoxy bis (methyl) Acrylate, bisphenol F (poly) ethoxy di(meth) acrylate, ethylene glycol di(meth) acrylate, (poly) ethylene glycol di (meth) acrylate Di(meth)acrylate of ε-caprolactone adduct of ester, hydroxytrimethylacetic acid neopentyl glycol (for example, KAYARAD HX-220, HX-620, etc., manufactured by Nippon Kayaku Co., Ltd.) .

Examples of the trifunctional or higher polyfunctional (meth) acrylate include di-trimethylolpropane tetra(meth)acrylate, trimethylolpropane tri(meth)acrylate, and trimethylol octane. Tris(meth)acrylate, trimethylolpropane polyethoxy tri(meth)acrylate, trimethylolpropane (poly)propoxy tri(meth)acrylate, trimethylolpropane ( Poly) hydroxymethyl groups such as ethoxy (poly) propoxy tri(meth) acrylate; neopentyl alcohol tri(meth) acrylate, neopentyl alcohol poly ethoxy tetra (meth) acrylate Ester, neopentyl alcohol (poly) propoxy tetra (meth) acrylate, neopentyl alcohol tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol Neopentyl alcohols such as penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate; ginseng [(meth)acryloyloxyethyl]trimeric isocyanate, caprolactone modification Reference to [(meth)acryloyloxyethyl]trimeric isocyanate; succinic acid modified pentaerythritol triacrylate, succinic acid modified dipentaerythritol pentaacrylate.

Examples of the (poly)ester (meth) acrylate oligomer include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, neopentyl glycol, and polyethylene glycol. , (poly) propylene glycol and other glycols, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 2-methyl-1,8 -octanediol, 3-methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, 2-butyl-2-ethyl-1,3-propanediol, etc. Linear or branched alkanediols, alicyclic alkanediols such as cyclohexane-1,4-dimethanol, bisphenol A (poly)ethoxy glycol, or bisphenol A (poly)propoxy a diol compound such as a diol and the aforementioned dibasic acid A (poly)ester diol of a reactant thereof or an anhydride thereof, a reaction product with (meth)acrylic acid, or the like.

The urethane (meth) acrylate oligomer may, for example, be a diol compound (for example, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1, 4-butanediol, neopentyl glycol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 2-methyl-1,8-octanediol, 3- Methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, 2-butyl-2-ethyl-1,3-propanediol, cyclohexane-1,4 - dimethanol, polyethylene glycol, polypropylene glycol, bisphenol A polyethoxy diol, bisphenol A polypropoxy diol, etc.) or such diol compounds with dibasic acids or anhydrides (eg succinic acid, a polyester diol of a reactant of adipic acid, sebacic acid, dimer acid, isophthalic acid, terephthalic acid, phthalic acid or such anhydrides, and an organic polyisocyanate (for example, tetramethylene Chain-like saturated hydrocarbon isocyanate such as bis-isocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate or 2,4,4-trimethylhexamethylene diisocyanate; Carbaryl diisocyanate, norbornane diisocyanate, dicyclohexylmethane diisocyanate, methylene double ( a cyclic saturated hydrocarbon isocyanate such as 4-cyclohexyl isocyanate), hydrogenated diphenylmethane diisocyanate, hydrogenated xylene diisocyanate or hydrogenated toluene diisocyanate; 2,4-tolyl diisocyanate, 1,3-extended xylylene Aromatic esters such as isocyanate, p-phenylene diisocyanate, 3,3'-dimethyl-4,4'-diisocyanate, 6-isopropyl-1,3-phenyl diisocyanate, 1,5-naphthalene diisocyanate The reaction is carried out by reacting a polyisocyanate with a hydroxyl group-containing (meth) acrylate.

Epoxy (meth) acrylate oligomers have epoxy a compound of a base and a carboxylate compound of (meth)acrylic acid. For example, a phenol novolac type epoxy (meth) acrylate, a cresol novolac type epoxy (meth) acrylate, and a hydroxy phenyl methane type epoxy group may be mentioned. (Meth) acrylate, dicyclopentadiene phenol type epoxy (meth) acrylate, bisphenol A type epoxy (meth) acrylate, bisphenol F type epoxy (meth) acrylate Ester, biphenol type epoxy (meth) acrylate, bisphenol A novolac type epoxy (meth) acrylate, naphthalene skeleton-containing epoxy (meth) acrylate, glyoxal ring An oxy (meth) acrylate, a heterocyclic epoxy (meth) acrylate, or the like.

Examples of the vinyl compound include vinyl ethers, styrenes, and other vinyl compounds. Examples of the vinyl ethers include ethyl vinyl ether, propyl vinyl ether, hydroxyethyl vinyl ether, and ethylene glycol divinyl ether. Examples of the styrenes include styrene, methylstyrene, and ethylstyrene. Examples of the other vinyl compound include triallyl tripolyisocyanate and trimethylallyl trimer isocyanate.

Further, the cationically reactive monomer is not particularly limited as long as it is a compound having an epoxy group in general. Examples thereof include glycidyl (meth)acrylate, methyl glycidyl ether, ethyl glycidyl ether, butyl glycidyl ether, bisphenol A diglycidyl ether, and 3,4-epoxycyclohexylmethyl group. -3,4,-epoxycyclohexanecarboxylate ("Cyracure UVR-6110", manufactured by Union Carbide Co., Ltd.), 3,4-epoxycyclohexylethyl-3,4-epoxycyclohexane Alkyl carboxylate, vinyl cyclohexene oxide ("ELR-4206" manufactured by Union Carbide Co., Ltd.), limonenedioxide ("Celloxide 3000" manufactured by Daicel Co., Ltd.), etc. Cyclohexene, 3,4,-epoxy-4-methylcyclohexyl-2-epoxypropane, 2-(3,4-epoxycyclohexyl-5,5-spiro-3,4-ring Oxy)cyclohexane-intermediate Alkane, bis(3,4-epoxycyclohexyl) adipate (Cyracure UVR-6128, manufactured by Union Carbide Co., Ltd.), bis(3,4-epoxycyclohexylmethyl) adipate, Bis(3,4-epoxycyclohexyl)ether, bis(3,4-epoxycyclohexylmethyl)ether, bis(3,4-epoxycyclohexyl)diethyloxane, and the like.

Among these, the reactive compound (B) is preferably a monofunctional, bifunctional or trifunctional or higher (meth) from the viewpoint of improving the polymerizability and increasing the strength of the obtained spacer or the like. Acrylate and the like.

The reactive compound (B) of the present invention can be used singly or in combination of two or more. The use ratio of the reactive compound (B) in the composition is preferably from 30 to 250 parts by mass, more preferably from 50 to 200 parts by mass, per 100 parts by mass of the reactive polycarboxylic acid compound (A). When the amount of the reactive compound (B) used is from 30 to 250 parts by mass, the sensitivity of the composition, the heat resistance and the elastic properties of the obtained cured product and the like are further improved.

The photopolymerization initiator (C) of the present invention is capable of inducing polymerization of a reactive polyvalent carboxylic acid compound (A) and a reactive compound (B) other than the reactive polycarboxylic acid compound (A) by inducing an active energy ray. The ingredients of the active species that started. Examples of such a photopolymerization initiator (C) include a mercaptophosphine compound, a benzammonium compound, an acetophenone compound, a biimidazole compound, and the like.

Wherein, the photopolymerization initiator is obtained by using a mercaptophosphine compound and a benzammonium compound in combination, and the reflectance, solder heat resistance, and the like are obtained even if the heat treatment step is not performed after the photohardening step by exposure. A cured product excellent in many properties such as adhesion and film hardness.

The mercaptophosphine-based photopolymerization initiator is not particularly limited as long as it is a photopolymerization initiator having a mercaptophosphine structure, and examples thereof include 2,4,6-trimethylbenzylidene-diphenyl-oxidation. Phosphine, bis(2,4,6-trimethylbenzylidene)-phenylphosphine oxide, bis(2,6-dimethylbenzylidene)-2,4,4-trimethyl-pentyl A fluorenylphosphine oxide compound such as phosphine oxide or (2,4,6-trimethylbenzylidene)ethoxyphenylphosphine oxide.

The benzamidine-based photopolymerization initiator is not particularly limited as long as it is a photopolymerization initiator having a benzammonium fluorene structure, and examples thereof include 1,2-octanedione and 1-[4-(benzene. , thiol)-2-(O-benzylidene hydrazide), 2-propanedione-2-O-benzimidoxime, 1-phenyl-1,2-propanedione-2-O - an oxime ester compound such as benzamidine.

The blending ratio of the mercaptophosphine-based photopolymerization initiator to the benzamidine-based photopolymerization initiator is not particularly limited, but, for example, 1 part by mass based on the benzamidine-based photopolymerization initiator, The lower limit of the amount of the compounding amount of the phosphine-based photopolymerization initiator is preferably 2 parts by mass in view of preventing a decrease in the reflectance of the cured product, so that the internal hardening is sufficiently performed to further enhance the density. From the viewpoint of the property, the lower limit is preferably 3 parts by mass, and the lower limit is particularly preferably 4 parts by mass from the viewpoint of reliably preventing the reflectance of the cured product from being lowered. On the other hand, with respect to 1 part by mass of the benzamidine-based photopolymerization initiator, the upper limit of the amount of the mercaptophosphine-based photopolymerization initiator increases the solder heat resistance and adhesion. In view of the above, the upper limit is preferably 100 parts by mass, and from the viewpoint of reliably preventing the hardness of the coating film from being lowered, the upper limit is more preferably 50 parts by mass, and the solder heat resistance and adhesion are made. From the standpoint of good balance to improve, the upper limit Good for 10 parts by mass.

That is, the ratio of the mercaptophosphine-based photopolymerization initiator to the benzamidine-based photopolymerization initiator is 1 part by mass relative to the benzamidine-based photopolymerization initiator, and the mercaptophosphine system is The photopolymerization initiator is usually from about 2 to 100 parts by mass, preferably from about 3 to 50 parts by mass, particularly preferably from 4 to 10 parts by mass.

The total amount of the fluorenylphosphine-based photopolymerization initiator and the benzamidine-based photopolymerization initiator is not particularly limited. For example, it is true that it is 100 parts by mass based on the reactive polycarboxylic acid compound (A). From the viewpoint of imparting photocurability and improving the mechanical strength of the cured product, the lower limit thereof is preferably 1 part by mass, and the lower limit is particularly preferably 2 parts by mass from the viewpoint of improving heat resistance. On the other hand, from the viewpoint of suppressing discoloration due to oxidative decomposition of the photopolymerization initiator and lowering the reflectance, the upper limit is preferably 30 parts by mass, and the adhesion to the substrate is considered. It is to be noted that the upper limit is particularly preferably 20 parts by mass.

In other words, the total amount of the fluorenylphosphine-based photopolymerization initiator and the benzamidine-based photopolymerization initiator is 100 parts by mass based on 100 parts by mass of the reactive polycarboxylic acid compound (A). It is particularly preferably from 1 to 30 parts by mass, more preferably from 2 to 20 parts by mass.

The titanium oxide (D) is prepared by whitening a cured product such as a coating film, and examples thereof include anatase-type titanium oxide and rutile-type titanium oxide having a rutile crystal structure. Among these, from the viewpoint of whiteness, rutile-type titanium oxide is preferred. The rutile-type titanium oxide system is, for example, "TR-600" manufactured by Fuji Titanium Industrial Co., Ltd. "TR-700", "TR-750", "TR-840"; "R-550", "R-580", "R-630", "R-820", "CR" manufactured by Ishihara Sangyo Co., Ltd. -50", "CR-60", "CR-80", "CR-90", "CR-93"; "KR-270", "KR-310" and "KR-380" manufactured by Titan Industrial Co., Ltd. "Wait. These may be used alone or in combination of two or more.

The amount of the titanium oxide (D) to be added is not particularly limited, but is preferably from 30 to 200% from the viewpoint of the whiteness and strength balance of the cured product with respect to 100 parts by mass of the reactive polycarboxylic acid compound (A). It is about 50 to 150 parts by mass.

In addition to the above components, the white active energy ray-curable resin composition of the present invention may contain various additives such as an antifoaming agent, a dispersing agent, a solvent, and an extender pigment as necessary.

A known one can be used as the antifoaming agent, and examples thereof include polyoxymethylene, hydrocarbon, and acrylic. The dispersing agent may, for example, be a coupling agent such as a decane system, a titanate system or an alumina system.

The solvent is used to adjust the viscosity or dryness of the white active energy ray-curable resin composition, and examples thereof include ketones such as methyl ethyl ketone and cyclohexane; aromatic hydrocarbons such as toluene and xylene; and methanol. Alcohols such as isopropanol and cyclohexanol; alicyclic hydrocarbons such as cyclohexane and methylcyclohexane; petroleum solvents such as petroleum ether and naphtha; cellosolve and butyl celesta Such as celsin; carbitol, butyl carbitol and other carbitol; ethyl acetate, butyl acetate, cyanidin acetate, butyl cyproterone acetate, carbene Acetate such as alcohol acetate or butyl carbitol acetate. These may be used alone or in combination of two or more.

The extender pigment is used to assist in enhancing the mechanical strength of the cured product (for example, the solder resist film after coating), and examples thereof include cerium oxide, barium sulfate, aluminum oxide, aluminum hydroxide, talc, and mica.

Further, in the present invention, the active energy ray-curable resin composition is colored white using titanium oxide, but a blue coloring agent or a yellow coloring agent may be appropriately added to the extent that the effects of the present invention are not affected depending on the application. , colorants such as black colorants. Specific examples of the coloring agent other than white include an organic pigment such as a phthalocyanine system such as phthalocyanine green or phthalocyanine blue, an anthraquinone or an azo-based organic pigment, and an inorganic pigment such as carbon black.

The method for producing the active energy ray-curable resin composition of the present invention is not limited to a specific method. For example, the above components may be blended at a predetermined ratio, and then a three-roll mill, a ball mill, or a sand mixture may be used at room temperature. A kneading means such as a machine or a stirring means such as a super mixer or a planetary mixer is kneaded or mixed to produce. Further, before the kneading or mixing, preliminary kneading or preliminary mixing may be performed as needed.

Next, a method of using the above-described white active energy ray-curable resin composition of the present invention will be described. Here, the case where the white active energy ray-curable resin composition of the present invention is applied onto a circuit board as a solder resist film will be described as an example.

The white active energy ray-curable resin composition of the present invention obtained in the above manner is used by screen printing, a spray coater, a bar coater, an applicator, or a blade coater. A known coating method such as a knife coater, a roll coater, or a gravure coater is applied to, for example, an electric charge formed by etching a copper foil. The printed wiring board of the road pattern is made to have a desired thickness. Further, after the application, if necessary, in order to volatilize the solvent in the white active energy ray-curable resin composition, it may be heated at a temperature of about 60 to 80 ° C for about 15 to 60 minutes to form a non-sticky form. Coating film. A negative film having a light transmissive pattern other than the land pattern of the circuit pattern is adhered to the white active energy ray-curable resin composition coated by a known coating method, and irradiated thereon The active energy ray (for example, ultraviolet ray) causes the coating film to be photohardened. Next, the non-exposed area corresponding to the land is removed by a weakly alkaline aqueous solution, whereby the coating film is developed, and the target solder resist film can be formed on the printed wiring board. In the above development method, a spray method, a bath method, or the like is used, and the weakly alkaline aqueous solution to be used is not particularly limited, and examples thereof include a 0.5 to 5% sodium carbonate aqueous solution. Further, when the coating film is not required to be applied, the white active energy ray-curable resin composition can be photocured without using a negative film.

The circuit board coated with the solder resist film obtained in such a manner is formed by soldering an electronic component by a jet welding method, a reflow soldering method, or the like to form an electronic circuit unit.

A cured product and a cured film of a photohardenable white active energy ray-curable resin composition, and a circuit board or a printed wiring board having the cured product or the cured film are also included in the present invention.

(Example)

Hereinafter, the present invention will be described in more detail by way of examples, but the invention is not limited to the examples. Further, in the examples, unless otherwise stated, the parts are represented by "parts", and "%" means mass%.

The softening point, epoxy equivalent, and acid value were measured according to the following conditions.

1) Epoxy equivalent: It was measured by the method according to JIS K7236:2001.

2) Softening point: Measurement was carried out in accordance with the method of JIS K7234:1986.

3) Acid value: It was measured in accordance with the method of JIS K0070:1992.

Examples 1-1 to 1-3

[Preparation of Reactive Polycarboxylic Acid Compound (A)]

NC-6300H (manufactured by Nippon Kasei Co., Ltd.; n=0 (64%) of the general formula (1), n=1 (23%), n=2 or more as the epoxy resin (a) in the amount shown in Table 1 was added. (13%); epoxy equivalent: 230 g/eq.), acrylic acid (abbreviated as AA, Mw=72) as the compound (b) and the amount of the compound (c) as described in Table 1 in the amounts shown in Table 1. Hydroxymethylpropionic acid (DMPA, Mw = 134). 3 g of triphenylphosphine as a catalyst and propylene glycol monomethyl ether monoacetate as a solvent were added so that the solid content became 80% by mass of the reaction liquid, and the reaction was carried out at 100 ° C for 24 hours to obtain reactivity. A solution of an epoxy carboxylic acid ester compound (E). The solid acid value (AV: mg.KOH/g) 5 or less was used as the reaction end point, and the next reaction was carried out. The acid value was measured in the reaction solution and converted to the acid value in terms of the solid content.

Next, in the solution of the reactive epoxy carboxylic acid ester compound (E), tetrahydrophthalic anhydride (abbreviated as the polybasic acid anhydride (d)) in the amount shown in Table 1 was added so that the solid content was 65% by mass. THPA) and propylene glycol monomethyl ether monoacetate as a solvent are heated to 100 ° C and then subjected to an acid addition reaction to obtain a reactive polycarboxylic acid compound (A) solution. The solid acid value (AV: mg.KOH/g) is shown in Table 1.

Comparative Example 1-1, 1-2

[Preparation of a reactive polycarboxylic acid compound for comparison]

Except that the epoxy resin of Examples 1-1 to 1-3 was changed from the epoxy resin (a) of Examples 1-1 to 1-3 to the cresol novolac type epoxy resin EOCN-103S (manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent) The same procedure as in Examples 1-1 to 1-3 except for 200 g/eq.) was carried out to obtain a carboxylic acid ester compound solution.

Then, in the same manner as in Examples 1-1 to 1-3, a reactive polycarboxylic acid compound solution for comparison was obtained. The solid acid value (AV: mgKOH/g) is shown in Table 1.

Comparative Example 1-3

[Comparison of Reactive Polycarboxylic Acid Compounds Without Aromatic Rings]

In a 2 liter separable flask equipped with a stirrer, a thermometer, a reflux condenser, a dropping funnel, and a nitrogen introduction tube, 900 g of diethylene glycol dimethyl ether as a solvent and peroxidation as a polymerization initiator were added. After 21.4 g of tert-butyl 2-ethylhexanoate (Perbutyl® O manufactured by Nippon Oil & Fat Co., Ltd.), it was heated to 90 °C. After heating, 309.9 g of methacrylic acid, 116.4 g of methyl methacrylate, and 109.8 g of lactam-modified 2-hydroxyethyl methacrylate (Placcel FM1 manufactured by Daicel Co., Ltd.) were used as a polymerization initiation. 21.4 g of bis(4-tert-butylcyclohexyl) peroxydicarbonate (Peroyl TCP, manufactured by Nippon Oil & Fat Co., Ltd.) was added dropwise for 3 hours, and then matured for 6 hours to obtain a carboxyl group-containing Copolymerized resin. Further, the reaction was carried out under a nitrogen atmosphere.

Next, 3,4-epoxycyclohexyl methacrylate (manufactured by Daicel Co., Ltd.) was added to the obtained carboxyl group-containing copolymer resin. 363.9 g of Cyclomer A200), 3.6 g of dimethylbenzylamine as a ring-opening catalyst, and 1.80 g of hydroquinone monomethyl ether as a polymerization inhibitor, and heated to 100 ° C, and stirred. A ring-opening addition reaction of an epoxy group. After 16 hours, the acid value of the solid fraction was 108.9 mg. KOH/g, a solution of a carboxyl group-containing resin having a weight average molecular weight of 25,000 and containing 65 mass% (solid content) without an aromatic ring.

<Modulation of Composition of the Invention>

Each component shown in the following Table 2 was prepared according to the mixing ratio shown in the following Table 2, and mixed and dispersed at room temperature using a three-roll mill to prepare Examples 2-1 to 2-3 and Comparative Example 2-1. A white active energy ray-curable resin composition used up to 2-3.

The details of each component used in the examples and comparative examples are shown.

<Reactive Compound (B)>

B-1: Mix of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate Compound (KAYARAD DPHA, manufactured by Nippon Kasei Co., Ltd.)

<Photopolymerization initiator (C)>

C-1: mercaptophosphine photopolymerization initiator

‧Bis(2,4,6-trimethylbenzylidene)-phenylphosphine oxide (IRGACURE 819, manufactured by BASF)

C-2: benzylidene oxime photopolymerization initiator

‧1,2-octanedione, 1-[4-(phenylthio)-2-(O-benzhydrylhydrazine)] (IRGACURE OXE 01, manufactured by BASF)

<Titanium oxide (D)>

D-1: rutile-type titanium oxide (CR-80, manufactured by Ishihara Sangyo Co., Ltd.)

<Preparation of test piece>

A printed wiring board having a circuit pattern formed on a copper clad laminate (FR-4, thickness 1.6 mm, conductor thickness 35 μm) was subjected to surface treatment by polishing (polishing wheel) polishing (corresponding to English: mopping or buffing or polishing). Next, the compositions of the present invention of Examples 2-1 to 2-3 and Comparative Examples 2-1 to 2-3 were each applied to a printed wiring board by a screen printing method. Then, the prepared printed wiring board was dried at 80 ° C for 30 minutes in a hot air circulating drying oven. On the coating film of the printed wiring board after drying, an ultraviolet ray (wavelength 300 to 400 nm) of 2000 mJ/cm ² was exposed by an exposure apparatus (model HMW-680GW manufactured by ORC Co., Ltd.) (printing step) A cured coating film of the composition of the present invention was formed on the sheet to prepare a test piece. The thickness of the hard coat film is 15 to 20 μm.

<evaluation>

The composition of Examples 2-1 to 2-3 and Comparative Examples 2-1 to 2-3 and the test piece formed of the coating film thereof were subjected to the following evaluations. The evaluation results are shown together in Table 3.

(1) Reflectance

The reflectance at 450 nm of the test piece coated with the cured coating film was measured using a spectrophotometer U-3310H (manufactured by Hitachi, Ltd.: φ 60 mm integrating sphere).

(2) Light resistance

The obtained test piece was further irradiated with Super UV (90 mW) light for 24 hours to accelerate deterioration, and then a spectrophotometer U-3310H (manufactured by Hitachi) was used. Co., Ltd.: φ 60mm integrating sphere), measuring the change in color. ΔE*ab represents a change in color. The smaller the value, the smaller the change in color.

(3) Solder heat resistance

The hardened coating film of the test piece was immersed in a solder bath of 260 ° C for 10 seconds according to the test method of JIS C-6481, and then a peeling test by a cellophane tape was set to 1 cycle to The state of the coating film after the 1 to 2 cycles of the repeated operation was visually observed, and the evaluation was performed according to the following criteria.

○: No change in the coating film was observed after 2 cycles of repeated operations.

△: It was confirmed that the coating film after the two cycles of the repeated operation was changed.

×: It was confirmed that the coating film after one cycle of the repeated operation was peeled off.

(4) Adhesion

In accordance with JIS K-5600-5-6, 100 (10 × 10) squares of 1 mm were placed on the test piece, and a peeling test using a celluloid tape was performed, and the peeling state of the square was visually observed, and the calculation was performed at 100 The number of squares in the square that are not peeled off from the substrate.

(5) Coating hardness

According to the test method of JIS K-5600-5-4, the tip of the core was ground to a flat 3B to 9H pencil, and the hardened coating film on the copper foil of the test piece was pressed at an angle of 45°, and no coating film was recorded. The hardness of the peeling pencil.

From the above results, the white active energy ray-curable composition containing the reactive polycarboxylic acid compound (A) of the present invention of Examples 2-1 to 2-3 was compared with Comparative Examples 2-1 to 2 The composition of -3 exhibits excellent reflectance, light resistance, and solder heat resistance, and is excellent in adhesion and coating film hardness. Further, Example 2-1 in which DMPA (Compound (c)) was used in the preparation of the reactive polycarboxylic acid compound (A) was observed, and Example 2-2 was observed, compared with the unused Compound (c). Example 2-3, which showed more excellent adhesion.

(industrial availability)

The white active energy ray-curable resin composition of the present invention can obtain a cured product excellent in reflectance, solder heat resistance, adhesion, and coating film hardness without performing a heat curing step after the photo-curing step, and thus, for example, The use of the solder mask and the cover film of the printed wiring board has high use value.

Claims (6)

A white active energy ray-curable resin composition containing a reactive polycarboxylic acid compound (A), a reactive compound (B) other than the reactive polycarboxylic acid compound (A), and a photopolymerization initiator (C) And a titanium oxide (D), wherein the reactive polycarboxylic acid compound (A) is obtained by reacting a reactant (E) with a polybasic acid anhydride (d), and the reactant (E) is a compound of the formula (1) The epoxy resin (a) and the compound (b) having one or more polymerizable ethylenically unsaturated groups and one or more carboxyl groups in one molecule, and at least one or more of the hydroxyl groups in one molecule as required a reactant of compound (c) with one or more carboxyl groups; Where n represents a positive number from 0 to 2. The white active energy ray-curable resin composition according to the first aspect of the invention, wherein the reactive polycarboxylic acid compound (A) is obtained by reacting a reactant (E) with a polybasic acid anhydride (d). The reactant (E) is an epoxy resin (a) represented by the formula (1) and has one or more polymerizable groups in one molecule. A compound (b) having an ethylenically unsaturated group and one or more carboxyl groups, and a reaction product of a compound (c) having at least two or more hydroxyl groups and one or more carboxyl groups in one molecule. The white active energy ray-curable resin composition according to claim 1 or 2, wherein the photopolymerization initiator (C) is a mercaptophosphine-based photopolymerization initiator and a benzamidine-based photopolymer The polymerization initiator is blended in an amount of from 2 to 100 parts by mass based on 1 part by mass of the benzamidine-based photopolymerization initiator and the mercaptophosphine-based photopolymerization initiator. The white active energy ray-curable resin composition according to claim 3, wherein the mercaptophosphine-based photopolymerization initiator is selected from the group consisting of 2,4,6-trimethylbenzimidyl-diphenyl -phosphine oxide, bis(2,4,6-trimethylbenzylidene)-phenylphosphine oxide, bis(2,6-dimethylbenzylidene)-2,4,4-trimethyl One or more groups consisting of keto-pentylphosphine oxide and (2,4,6-trimethylbenzylidene)ethoxyphenylphosphine oxide, a benzamidine-based photopolymerization initiator Free choice of 1,2-octanedione, 1-[4-(phenylthio)-, 2-(O-benzylidene fluorenyl)], 2-propanedione-2-O-benzylidene One or more groups consisting of hydrazine and 1-phenyl-1,2-propanedione-2-O-benzylidene fluorene. A cured product which is a cured product of a white active energy ray-curable resin composition according to claim 1 of the patent application. A printed wiring board comprising a cured film of a white active energy ray-curable resin composition according to claim 1 of the patent application.