JP7462709B2 - Reactive polycarboxylic acid compound, active energy ray curable resin composition using the same, cured product thereof, and uses thereof - Google Patents

Description

The present invention relates to a novel reactive polycarboxylic acid compound (A), an active energy ray-curable resin composition containing the compound, and a cured product thereof. In particular, the present invention relates to a novel reactive polycarboxylic acid compound suitable as a resist material that can be used as a color resist, a resist material for color filters, and a black matrix material, an active energy ray-curable resin composition containing the compound, and a cured product thereof.

Printed wiring boards are required to be highly accurate and dense in order to make mobile devices smaller and lighter and to improve communication speeds. As a result, the demands on the solder resist that covers the circuits themselves are also becoming increasingly stringent. Even more than conventional demands, solder resists are now required to maintain higher heat resistance and thermal stability while also adhering to substrates, providing high insulation and being able to withstand electroless gold plating, and there is a demand for film-forming materials with tougher curing properties.

As one of these materials, a carboxylate compound obtained by reacting a general epoxy resin with a compound having a carboxylic acid and a hydroxyl group, and acrylic acid, is known as a material that has excellent developability despite its low acid value, and it is also known that this compound is suitable for use in resist inks (Patent Document 1).

On the other hand, acid-modified epoxy acrylates based on phenol aralkyl epoxy resins (such as NC-3000 manufactured by Nippon Kayaku) are generally known as materials that exhibit high toughness after curing, and their use as solder resists is also being investigated (Patent Document 2).

In addition, there is also known an attempt to apply an acid-modified epoxy acrylate having a phenol aralkyl type epoxy resin as a basic skeleton, in which carbon black or the like is dispersed, to a black matrix resist used in liquid crystal display panels or the like (Patent Document 3).
Furthermore, phenol aralkyl-type acid-modified epoxy acrylate compounds that have excellent dispersibility of color pigments and the like and good development properties even at high pigment concentrations have also been investigated (Patent Document 4).

Japanese Patent Application Laid-Open No. 06-324490 Japanese Patent Application Laid-Open No. 09-211860 JP 2005-055814 A JP 2015-163368 A

However, although the acid-modified epoxy acrylate having a phenol aralkyl type epoxy resin as a basic skeleton under study has good affinity with the resin and disperses the color pigment such as carbon black, further improvement in developability and higher heat resistance are required.
Therefore, an object of the present invention is to improve the above-mentioned problems of the conventional art and to provide a highly heat-resistant acid-modified epoxy acrylate compound having excellent dispersibility of color pigments and the like and good development properties even at a high pigment concentration, and an active energy ray-curable resin composition containing the same.

The inventors conducted extensive research to solve the above problems, and discovered that a resin composition using a reaction product of an epoxy resin having a polycyclic hydrocarbon group, an unsaturated group-containing carboxylic acid, and, if necessary, a compound having both a hydroxyl group and a carboxyl group in one molecule, and a specific polybasic acid anhydride, can solve the above problems, thus arriving at the present invention.

That is, the present invention provides:
[1] A reactive polycarboxylic acid compound (A) obtained by reacting an epoxy resin (a) represented by the following formula (1) with a carboxylic acid compound (b) having both a polymerizable ethylenically unsaturated group and a carboxy group in one molecule, and, if necessary, a compound (c) having both a hydroxyl group and a carboxy group in one molecule to obtain a reactive epoxy carboxylate compound (d) and reacting the resulting compound with a polybasic acid anhydride (e) represented by the following formula (2) or formula (3):

(In the formula, each Ar is independently either (I) or (II), and the molar ratio of (I) to (II) is (I)/(II) = 1 to 3. G represents a glycidyl group. n is the average number of repetitions and is a positive number in the range of 0 < n ≦ 5.)

(In formula (2), each R ₁ independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. m represents an integer of 1 to 3.)
[2] An active energy ray-curable resin composition comprising the reactive polycarboxylic acid compound (A) according to the preceding item [1];
[3] The active energy ray-curable resin composition according to the above item [2], which contains a reactive compound (B) other than the reactive polycarboxylic acid compound (A);
[4] The active energy ray-curable resin composition according to the above item [2] or [3], which contains a photopolymerization initiator.
[5] The active energy ray-curable resin composition according to any one of the above items [2] to [4], which is a molding material.
[6] The active energy ray-curable resin composition according to any one of the above items [2] to [4], which is a film-forming material;
[7] The active energy ray-curable resin composition according to any one of the above items [2] to [4], which is a resist material composition.
[8] A cured product of the active energy ray-curable resin composition according to any one of the above items [2] to [7].
[9] An article overcoated with the cured product according to the preceding item [8].
Regarding.

The active energy ray curable resin composition containing the reactive polycarboxylic acid compound (A) of the present invention not only gives a tough cured product, but also has excellent resin properties even in a state where the solvent is simply dried. In addition, the cured product obtained by curing the active energy ray curable resin composition of the present invention with active energy rays such as ultraviolet rays has excellent heat resistance and can be finely developed with an alkali, and is therefore suitable for use as a molding material, a film-forming material, or a resist material.
In addition, due to the high affinity with color pigments, the reactive polycarboxylic acid compound of the present invention and the active energy ray-curable resin composition containing the same exhibit good developability even at high pigment concentrations, and are therefore suitable for use as color resists, resist materials for color filters, in particular black matrix materials, and the like.

Furthermore, the active energy ray-curable resin composition containing the reactive polycarboxylic acid compound (A) of the present invention has thermal and mechanical toughness, good storage stability, and high reliability in terms of resistance to high temperature and high humidity and thermal shock, and is therefore also used in applications requiring particularly high reliability, such as solder resist for printed wiring boards, interlayer insulating materials for multilayer printed wiring boards, solder resist for flexible printed wiring boards, plating resist, and photosensitive optical waveguides.

The present invention will be described in detail below.
The reactive polycarboxylic acid compound (A) of the present invention can be obtained by reacting an epoxy resin (a) having a structure represented by the following formula (1) (with a carboxylic acid compound (b) having both a polymerizable ethylenically unsaturated group and a carboxy group in one molecule, and, if necessary, a compound (c) having both a hydroxyl group and a carboxy group in one molecule to obtain a reactive epoxy carboxylate compound (d), and then reacting the resulting compound with a polybasic acid anhydride (e) represented by the following formula (2) or formula (3).

(In the formula, each Ar is independently either (I) or (II), and the molar ratio of (I) to (II) is (I)/(II) = 1 to 3. G represents a glycidyl group. n is the average number of repetitions and is a positive number in the range of 0 < n ≦ 5.)

(In formula (2), each R ₁ independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. m represents an integer of 1 to 3.)

First, we will explain the carboxylation process for imparting reactivity to a carboxylate compound to obtain a reactive epoxy carboxylate compound (d).

The epoxy resin (a) represented by the formula (1) used in the present invention (hereinafter, also simply referred to as "epoxy resin (a)") is generally available under various trade names, for example, NC-3500 (manufactured by Nippon Kayaku Co., Ltd.).
In the formula (1), Ar (I) may be any of ortho, meta and para isomers. In the present invention, the meta isomer represented by the following formula (4) is preferred.

In the present invention, the carboxylic acid compound (b) having both a polymerizable ethylenically unsaturated group and a carboxyl group in one molecule (hereinafter also referred to simply as "carboxylic acid compound (b)") is reacted to impart reactivity to active energy rays. There are no limitations on the number of ethylenically unsaturated groups and carboxyl groups, so long as there is at least one each in the molecule.

Examples of carboxylic acid compounds (b) having both a polymerizable ethylenically unsaturated group and a carboxy group in one molecule include (meth)acrylic acids, crotonic acid, α-cyanocinnamic acid, cinnamic acid, or reaction products of saturated or unsaturated dibasic acids with unsaturated group-containing monoglycidyl compounds. In the above, examples of (meth)acrylic acids include (meth)acrylic acid, β-styrylacrylic acid, β-furfurylacrylic acid, (meth)acrylic acid dimer, monocarboxylic acid compounds containing one carboxy group in one molecule, such as half esters which are equimolar reaction products of saturated or unsaturated dibasic acid anhydrides and (meth)acrylate derivatives having one hydroxyl group in one molecule, and half esters which are equimolar reaction products of saturated or unsaturated dibasic acids and monoglycidyl (meth)acrylate derivatives, as well as polycarboxylic acid compounds having multiple carboxy groups in one molecule, such as half esters which are equimolar reaction products of (meth)acrylate derivatives having multiple hydroxyl groups in one molecule, and half esters which are equimolar reaction products of saturated or unsaturated dibasic acids and glycidyl (meth)acrylate derivatives having multiple epoxy groups.

Among these, in consideration of the stability of the reaction between the epoxy resin (a) and the carboxylic acid compound (b), the carboxylic acid compound (b) is preferably a monocarboxylic acid, and even when a monocarboxylic acid and a polycarboxylic acid are used in combination, it is preferable that the value represented by the molar amount of monocarboxylic acid/the molar amount of polycarboxylic acid is 15 or more.
Most preferred are (meth)acrylic acid, a reaction product of (meth)acrylic acid and ε-caprolactone, and cinnamic acid in terms of sensitivity when made into an active energy ray-curable resin composition.
As a compound having one or more polymerizable ethylenically unsaturated groups and one or more carboxy groups in one molecule, it is preferable that the compound does not have a hydroxyl group.

The compound (c) having both a hydroxyl group and a carboxyl group in one molecule used in the present invention (hereinafter also referred to simply as "compound (c)") is reacted with a carboxylate compound for the purpose of introducing a hydroxyl group into the carboxylate compound. These include compounds having one hydroxyl group and one carboxyl group in one molecule, compounds having two or more hydroxyl groups and one carboxyl group in one molecule, and compounds having one or more hydroxyl groups and two or more carboxyl groups in one molecule.
Examples of compounds having one hydroxyl group and one carboxyl group in one molecule include hydroxypropionic acid, hydroxybutanoic acid, hydroxystearic acid, etc. Examples of compounds having two or more hydroxyl groups and one carboxyl group in one molecule include dimethylolacetic acid, dimethylolpropionic acid, dimethylolbutanoic acid, etc. Examples of compounds having one or more hydroxyl groups and two or more carboxyl groups in one molecule include hydroxyphthalic acid, etc.
Among these, those containing two or more hydroxyl groups per molecule are preferred in consideration of the effects of the present invention. Furthermore, those containing one carboxyl group per molecule are preferred in consideration of the stability of the carboxylation reaction. Most preferred are those containing two hydroxyl groups and one carboxyl group per molecule. Considering the availability of raw materials, dimethylolpropionic acid and dimethylolbutanoic acid are particularly suitable.
As a compound having one or more hydroxyl groups and one or more carboxyl groups in one molecule, it is preferable that the compound does not have a polymerizable ethylenically unsaturated group.

The ratio of epoxy resin (a), carboxylic acid compound (b) and compound (c) used in this carboxylation reaction should be changed as appropriate depending on the application. That is, when all epoxy groups are carboxylated, no unreacted epoxy groups remain, and the storage stability of the reactive epoxy carboxylate compound (d) is high. In this case, only the reactivity due to the introduced double bonds is utilized.

On the other hand, by reducing the amount of carboxylic acid compound (b) and compound (c) charged and leaving unreacted residual epoxy groups, it is possible to utilize the reactivity of the introduced unsaturated bonds and the reaction of the remaining epoxy groups, such as a polymerization reaction or a thermal polymerization reaction, in combination with a photocationic catalyst. However, in this case, care should be taken when storing the reactive epoxy carboxylate compound (d) and when considering the manufacturing conditions.

When producing a reactive epoxy carboxylate compound (d) that does not leave epoxy groups, the total amount of the carboxylic acid compound (b) and compound (c) is preferably 90 to 120 equivalent percent per equivalent of the epoxy resin (a). Within this range, production can be performed under relatively stable conditions. If the amount of the carboxylic acid compound charged is greater than this, excess carboxylic acid compound (b) and compound (c) will remain, which is not preferable.

If epoxy groups are to remain, the total amount of the carboxylic acid compound (b) and compound (c) is preferably 20 to 90 equivalent percent per equivalent of the epoxy resin (a). Outside this range, the effect of the composite curing will be weak. Of course, in this case, sufficient care must be taken to prevent gelation during the reaction and to ensure the stability of the reactive epoxy carboxylate compound (d) over time.

The carboxylation reaction can be carried out without a solvent, or diluted with a solvent. There are no particular limitations on the solvent that can be used here, as long as it is an inert solvent for the carboxylation reaction.

The amount of solvent used should be adjusted appropriately depending on the viscosity and use of the resulting resin, but it is preferably used so that the solids content is 90 to 30% by mass, more preferably 80 to 50% by mass.

Specific examples include aromatic hydrocarbon solvents such as toluene, xylene, ethylbenzene, and tetramethylbenzene, aliphatic hydrocarbon solvents such as hexane, octane, and decane, and mixtures thereof such as petroleum ether, white gasoline, and solvent naphtha, as well as ester solvents, ether solvents, and ketone solvents.

Examples of ester solvents include alkyl acetates such as ethyl acetate, propyl acetate, and butyl acetate; cyclic esters such as γ-butyrolactone; mono- or polyalkylene glycol monoalkyl ether monoacetates such as ethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether monoacetate, diethylene glycol monoethyl ether monoacetate, triethylene glycol monoethyl ether monoacetate, diethylene glycol monobutyl ether monoacetate, propylene glycol monomethyl ether monoacetate, and butylene glycol monomethyl ether acetate; and polycarboxylic acid alkyl esters such as dialkyl glutarate, dialkyl succinate, and dialkyl adipate.

Examples of ether solvents include alkyl ethers such as diethyl ether and ethyl butyl ether, glycol ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, triethylene glycol dimethyl ether and triethylene glycol diethyl ether, and cyclic ethers such as tetrahydrofuran.

Ketone solvents include acetone, methyl ethyl ketone, cyclohexanone, isophorone, etc.

In addition, the reaction can be carried out in a single or mixed organic solvent using a reactive compound (B) other than the reactive polycarboxylic acid compound (A) described below (hereinafter also referred to simply as "reactive compound (B)"). In this case, when used as a curable resin composition, it is preferable because it can be used directly as a composition.

During the reaction, it is preferable to use a catalyst to promote the reaction, and the amount of the catalyst used is 0.1 to 10 parts by mass per 100 parts by mass of the total amount of the reactants, i.e., the epoxy resin (a), the carboxylic acid compound (b) and the compound (c), and optionally the solvent and other reactants. The reaction temperature is 60 to 150°C, and the reaction time is preferably 5 to 60 hours. Specific examples of catalysts that can be used include known general basic catalysts such as triethylamine, benzyldimethylamine, triethylammonium chloride, benzyltrimethylammonium bromide, benzyltrimethylammonium iodide, triphenylphosphine, triphenylstibine, methyltriphenylstibine, chromium octanoate, and zirconium octanoate.

A thermal polymerization inhibitor can also be used. As the thermal polymerization inhibitor, it is preferable to use hydroquinone monomethyl ether, 2-methylhydroquinone, hydroquinone, diphenylpicrylhydrazine, diphenylamine, 3,5-di-tert-butyl-4-hydroxytoluene, etc.

The carboxylation reaction is terminated when the acid value of the sample reaches 5 mg KOH/g or less, preferably 3 mg KOH/g or less, while sampling is performed as needed.

The preferred molecular weight range of the reactive epoxy carboxylate compound (d) thus obtained is a weight average molecular weight in terms of polystyrene measured by GPC of 500 to 50,000, more preferably 1,000 to 30,000, and particularly preferably 1,000 to 10,000.

If the molecular weight is smaller than this, the toughness of the cured product will not be sufficient, and if it is larger than this, the viscosity will be too high, making coating, etc. difficult.

Next, the acid addition step (hereinafter also simply referred to as "this acid addition reaction") will be described in detail. The acid addition step is carried out for the purpose of introducing a carboxy group, if necessary, into the reactive epoxy carboxylate compound (d) obtained in the previous step to obtain a reactive polycarboxylic acid compound (A). That is, the hydroxyl group generated by the carboxylation reaction is subjected to an addition reaction with the polybasic acid anhydride (e) represented by the above formula (2) or (3) (hereinafter also simply referred to as "polybasic acid anhydride (e)"), thereby introducing a carboxy group via an ester bond.

Examples of the alkyl group having 1 to 10 carbon atoms in the formula (2) include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group. A hydrogen atom, R ₁ in the formula (2) is preferably a methyl group.

The polybasic acid anhydride (e) is preferably a compound represented by the following formula (5).

The reaction of adding the polybasic acid anhydride (e) can be carried out by adding the polybasic acid anhydride (e) to the carboxylation reaction solution. The amount of addition should be appropriately changed depending on the application.

For example, when the reactive polycarboxylic acid compound (A) of the present invention is to be used as an alkaline aqueous solution development type resist material, the amount of polybasic acid anhydride (e) added is preferably calculated so that the solid acid value (based on JIS K5601-2-1:1999) of the finally obtained reactive polycarboxylic acid compound (A) is preferably 20 to 120 mgKOH/g, more preferably 30 to 110 mgKOH/g. When the solid acid value is within this range, the active energy ray curable resin composition of the present invention exhibits good alkaline aqueous solution developability. In other words, there is good patterning property, a wide control range for overdevelopment, and no excess acid anhydride remains.

During the reaction, it is preferable to use a catalyst to promote the reaction, and the amount of the catalyst used is 0.1 to 10 parts by mass based on the total amount of the reactants, i.e., the epoxy compound (a), the carboxylic acid compound (b) and the reactive epoxy carboxylate compound (d) obtained from the compound (c), and the polybasic acid anhydride (e), and optionally the solvent and other reactants. The reaction temperature is 60 to 150°C, and the reaction time is preferably 5 to 60 hours. Specific examples of catalysts that can be used include triethylamine, benzyldimethylamine, triethylammonium chloride, benzyltrimethylammonium bromide, benzyltrimethylammonium iodide, triphenylphosphine, triphenylstibine, methyltriphenylstibine, chromium octanoate, zirconium octanoate, etc.

This acid addition reaction can be carried out without a solvent or diluted with a solvent. There are no particular limitations on the solvent that can be used here, so long as it is an inert solvent for the acid addition reaction. Also, if a solvent is used in the preceding carboxylation reaction, the product can be directly subjected to the next acid addition reaction without removing the solvent, provided that the solvent is inert for both reactions. The solvent that can be used may be the same as that used in the carboxylation reaction.

The amount of solvent used should be adjusted appropriately depending on the viscosity and use of the resulting resin, but it is preferably used so that the solids content is 90 to 30% by mass, more preferably 80 to 50% by mass.

In addition, the reactive compound (B) can be used alone or in a mixed organic solvent. In this case, when used as a curable resin composition, it is preferable because it can be used directly as a composition.

It is also preferable to use the same thermal polymerization inhibitors as those exemplified in the carboxylation reaction described above.

This acid addition reaction is terminated when the acid value of the reactant reaches a range of plus or minus 10% of the set acid value, while sampling is performed as necessary.

The preferred molecular weight range of the reactive polycarboxylic acid compound (A) thus obtained is a weight average molecular weight in terms of polystyrene measured by GPC (gel permeation chromatography) of 500 to 50,000, more preferably 1,000 to 30,000, and particularly preferably 1,000 to 10,000.

If the molecular weight is smaller than this, the toughness of the cured product will not be sufficient, and if it is larger than this, the viscosity will be too high, making coating, etc. difficult.

Specific examples of reactive compounds (B) that can be used in the present invention include so-called reactive oligomers such as radical reaction type acrylates, cationic reaction type other epoxy compounds, and vinyl compounds that react with both.

Examples of acrylates that can be used include monofunctional (meth)acrylates, polyfunctional (meth)acrylates, as well as epoxy acrylates, polyester acrylates, urethane acrylates, etc.

Examples of monofunctional (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, lauryl (meth)acrylate, polyethylene glycol (meth)acrylate, polyethylene glycol (meth)acrylate monomethyl ether, phenylethyl (meth)acrylate, isobornyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, and tetrahydrofurfuryl (meth)acrylate.

Examples of polyfunctional (meth)acrylates include butanediol di(meth)acrylate, hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, nonanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene di(meth)acrylate, polyethylene glycol di(meth)acrylate, tris(meth)acryloyloxyethyl isocyanurate, polypropylene glycol di(meth)acrylate, adipic acid epoxy di(meth)acrylate, bisphenol ethylene oxide di(meth)acrylate, hydrogenated bisphenol ethylene oxide di(meth)acrylate, bisphenol di(meth)acrylate, acrylate, di(meth)acrylate of hydroxypivalic acid neopen glycol ε-caprolactone adduct, poly(meth)acrylate of reaction product of dipentaerythritol and ε-caprolactone, dipentaerythritol poly(meth)acrylate, trimethylolpropane tri(meth)acrylate, triethylolpropane tri(meth)acrylate and its ethylene oxide adduct, pentaerythritol tri(meth)acrylate and its ethylene oxide adduct, pentaerythritol tetra(meth)acrylate and its ethylene oxide adduct, dipentaerythritol hexa(meth)acrylate and its ethylene oxide adduct, etc.

Examples of vinyl compounds that can be used include vinyl ethers, styrenes, and other vinyl compounds. Examples of vinyl ethers include ethyl vinyl ether, propyl vinyl ether, hydroxyethyl vinyl ether, and ethylene glycol divinyl ether. Examples of styrenes include styrene, methylstyrene, and ethylstyrene. Examples of other vinyl compounds include triallyl isocyanurate and trimethallyl isocyanurate.

Furthermore, examples of so-called reactive oligomers include urethane acrylates, which have both a functional group sensitive to active energy rays and a urethane bond in the same molecule, polyester acrylates, which similarly have both a functional group sensitive to active energy rays and an ester bond in the same molecule, and epoxy acrylates, which are derived from epoxy resins and have both a functional group sensitive to active energy rays in the same molecule, and reactive oligomers in which these bonds are used in combination.

In addition, the cationic reactive monomer is not particularly limited as long as it is a compound having an epoxy group. For example, glycidyl (meth)acrylate, methyl glycidyl ether, ethyl glycidyl ether, butyl glycidyl ether, bisphenol A diglycidyl ether, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexane carboxylate (e.g., "Cyracure UVR-6110" manufactured by Union Carbide), 3,4-epoxycyclohexylethyl-3,4-epoxycyclohexane carboxylate, vinylcyclohexene dioxide (e.g., "ELR-4206" manufactured by Union Carbide), limonene dioxide (e.g., "Celloxide 3000" manufactured by Daicel Chemical Industries, Ltd.), a Examples of such compounds include arylcyclohexene dioxide, 3,4-epoxy-4-methylcyclohexyl-2-propylene oxide, 2-(3,4-epoxycyclohexyl-5,5-spiro-3,4-epoxy)cyclohexane-m-dioxane, bis(3,4-epoxycyclohexyl)adipate (such as Union Carbide's "Cyracure UVR-6128"), bis(3,4-epoxycyclohexylmethyl)adipate, bis(3,4-epoxycyclohexyl)ether, bis(3,4-epoxycyclohexylmethyl)ether, and bis(3,4-epoxycyclohexyl)diethylsiloxane.

Of these, radical curing acrylates are the most preferred reactive compound (B). In the case of cationic types, carboxylic acids react with epoxy groups, making it necessary to use a two-liquid mixture type.

The reactive polycarboxylic acid compound (A) of the present invention can be mixed with another reactive compound (B) to obtain the active energy ray-curable resin composition of the present invention. At this time, other components may be added as appropriate depending on the application.

The active energy ray-curable resin composition of the present invention contains 97 to 5 parts by mass, preferably 87 to 10 parts by mass, of a reactive polycarboxylic acid compound (A) and 3 to 95 parts by mass, more preferably 3 to 90 parts by mass, of another reactive compound (B) in the composition. If necessary, the composition may contain 0 to 80 parts by mass of other components.

In addition, in order to adapt the active energy ray-curable resin composition of the present invention to various applications, other components can be added to the composition up to 70 parts by weight. Examples of other components include photopolymerization initiators, other additives, coloring materials, curing accelerators, and volatile solvents added to adjust viscosity for the purpose of imparting coating suitability, etc. Examples of other components that can be used are listed below.

The active energy ray-curable resin composition of the present invention may further contain a photopolymerization initiator. As the photopolymerization initiator, a radical type photopolymerization initiator or a cationic type photopolymerization initiator is preferable.
Examples of the radical type photopolymerization initiator include benzoins such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, and benzoin isobutyl ether; acetophenones such as acetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 2-hydroxy-2-methyl-phenylpropan-1-one, diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, and 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propan-1-one; 2-ethylanthraquinone, 2-t-butylanthraquinone, 2-chloroanthraquinone, and the like. Examples of known general radical photopolymerization initiators include anthraquinones such as quinone and 2-amyl anthraquinone; thioxanthones such as 2,4-diethylthioxanthone, 2-isopropylthioxanthone, and 2-chlorothioxanthone; ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzophenones such as benzophenone, 4-benzoyl-4'-methyldiphenyl sulfide and 4,4'-bismethylaminobenzophenone; and phosphine oxides such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide.

Cationic photopolymerization initiators include diazonium salts of Lewis acids, iodonium salts of Lewis acids, sulfonium salts of Lewis acids, phosphonium salts of Lewis acids, other halides, triazine initiators, borate initiators, and other photoacid generators.

Examples of diazonium salts of Lewis acids include p-methoxyphenyldiazonium fluorophosphonate and N,N-diethylaminophenyldiazonium hexafluorophosphonate (e.g., San-Aid SI-60L/SI-80L/SI-100L manufactured by Sanshin Chemical Industry Co., Ltd.), examples of iodonium salts of Lewis acids include diphenyliodonium hexafluorophosphonate and diphenyliodonium hexafluoroantimonate, examples of sulfonium salts of Lewis acids include triphenylsulfonium hexafluorophosphonate (e.g., Cyracure UVI-6990 manufactured by Union Carbide Co., Ltd.) and triphenylsulfonium hexafluoroantimonate (e.g., Cyracure UVI-6974 manufactured by Union Carbide Co., Ltd.), and examples of phosphonium salts of Lewis acids include triphenylphosphonium hexafluoroantimonate.

Other halides include 2,2,2-trichloro-[1-4'-(dimethylethyl)phenyl]ethanone (TrigonalPI manufactured by AKZO, etc.), 2,2-dichloro-1-4-(phenoxyphenyl)ethanone (Sandray 1000 manufactured by Sandoz, etc.), and α,α,α-tribromomethylphenylsulfone (BMPS manufactured by Seitetsu Kagaku, etc.). Triazine initiators include 2,4,6-tris(trichloromethyl)-triazine, 2,4-trichloromethyl-(4'-methoxyphenyl)-6-triazine (Triazine A manufactured by Panchim, etc.), 2,4-trichloromethyl-(4'-methoxystyryl)-6-triazine (Triazine PMS manufactured by Panchim, etc.), 2,4-trichloromethyl-(pipronyl)-6-triazine (Panchim, etc.), and 2,4-trichloromethyl-(pipronyl)-6-triazine (Panchim, etc.). Examples include Triazine PP manufactured by Panchim, 2,4-trichloromethyl-(4'-methoxynaphthyl)-6-triazine (Triazine B manufactured by Panchim, etc.), 2[2'(5-methylfuryl)ethylidene]-4,6-bis(trichloromethyl)-s-triazine (manufactured by Sanwa Chemical Co., Ltd., etc.), and 2(2'-furylethylidene)-4,6-bis(trichloromethyl)-s-triazine (manufactured by Sanwa Chemical Co., Ltd.).

Examples of borate-based photopolymerization initiators include NK-3876 and NK-3881 manufactured by Nippon Kanko Shikushiki Co., Ltd., and other photoacid generators include 9-phenylacridine, 2,2'-bis(o-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2-biimidazole (Kurokane Kasei Co., Ltd. Biimidazole, etc.), 2,2-azobis(2-amino-propane) dihydrochloride (Wako Pure Chemical Industries, Ltd. V50, etc.), 2,2-azobis[2-(imidazolin-2yl)propane]dihydrochloride (Wako Pure Chemical Industries, Ltd. V50, etc.), and 2,2-azobis[2-(imidazolin-2yl)propane]dihydrochloride (Wako Pure Chemical Industries, Ltd. V50, etc.). Examples include [eta-5-2-4-(cyclopentadecyl)(1,2,3,4,5,6,eta)-(methylethyl)-benzene]iron(II) hexafluorophosphonate (Irgacure 261, Ciba Geigy), and bis(y5-cyclopentadienyl)bis[2,6-difluoro-3-(1H-pyri-1-yl)phenyl]titanium (Ciba Geigy CGI-784, etc.).

In addition, azo-based initiators such as azobisisobutyronitrile, and heat-sensitive peroxide-based radical initiators such as benzoyl peroxide may be used in combination. In addition, both radical and cationic photopolymerization initiators may be used in combination. One type of photopolymerization initiator may be used alone, or two or more types may be used in combination.

Among these, radical photopolymerization initiators are particularly preferred, taking into consideration the properties of the reactive polycarboxylic acid compound (A) of the present invention.

Furthermore, the active energy ray-curable resin composition of the present invention may contain a coloring pigment. As the coloring pigment, for example, a so-called extender pigment that is not intended for coloring may also be used. Examples of the coloring pigment include talc, barium sulfate, calcium carbonate, magnesium carbonate, barium titanate, aluminum hydroxide, silica, clay, etc.

Furthermore, the active energy ray-curable resin composition of the present invention may contain other additives as necessary. Examples of other additives that can be used include heat curing catalysts such as melamine, thixotropy-imparting agents such as aerosil, silicone-based and fluorine-based leveling agents and defoamers, polymerization inhibitors such as hydroquinone and hydroquinone monomethyl ether, stabilizers, and antioxidants.

Other resins that are not reactive to active energy rays (so-called inert polymers) can also be used, such as other epoxy resins, phenolic resins, urethane resins, polyester resins, ketone formaldehyde resins, cresol resins, xylene resins, diallyl phthalate resins, styrene resins, guanamine resins, natural and synthetic rubbers, acrylic resins, polyolefin resins, and modified products thereof. These are preferably used in an amount of up to 40 parts by mass in the resin composition.

In particular, when using the reactive polycarboxylic acid compound (A) for solder resist applications, it is preferable to use a known general epoxy resin as a resin that does not exhibit reactivity to active energy rays. This is because the carboxyl groups derived from the reactive polycarboxylic acid compound (A) remain even after reaction and curing with active energy rays, and as a result, the cured product has poor water resistance and hydrolysis resistance. Therefore, by using an epoxy resin, the remaining carboxyl groups are further carboxylated, forming an even stronger crosslinked structure. The known general epoxy resin can use the above-mentioned cation-reactive monomer.

In addition, a volatile solvent can be added to the resin composition in an amount of up to 50 parts by weight, more preferably up to 35 parts by weight, to adjust the viscosity depending on the intended use.

The active energy ray-curable resin composition of the present invention is easily cured by active energy rays. Specific examples of active energy rays include ultraviolet rays, visible light rays, infrared rays, electromagnetic waves such as X-rays, gamma rays, and laser beams, and particle rays such as alpha rays, beta rays, and electron beams. In consideration of the preferred applications of the present invention, among these, ultraviolet rays, laser beams, visible light, and electron beams are preferred.

In the present invention, a molding material refers to a material used in applications in which an uncured composition is placed in a mold or pressed against a mold to form an object, and then a curing reaction is caused by exposure to active energy rays to form the object, or an uncured composition is irradiated with focused light such as a laser to cause a curing reaction to form the object.

Specific suitable applications include flat sheets, sealing materials for protecting elements, so-called nanoimprint materials in which a finely processed "mold" is pressed against an uncured composition to perform fine molding, and peripheral sealing materials for light-emitting diodes and photoelectric conversion elements, which have particularly strict thermal requirements.

In the present invention, a film-forming material is used for the purpose of coating the surface of a substrate. Specific applications include ink materials such as gravure ink, flexographic ink, silk screen ink, and offset ink; coating materials such as hard coats, top coats, overprint varnishes, and clear coats; adhesive materials such as various adhesives and pressure sensitive adhesives for lamination and optical disks; and resist materials such as solder resists, etching resists, and resists for micromachines. Furthermore, a so-called dry film, in which a film-forming material is temporarily applied to a peelable substrate to form a film, and then the film is attached to the intended substrate to form a film, also falls under the category of a film-forming material.

The present invention includes a cured product obtained by irradiating the curable resin composition with active energy rays, and also includes a multi-layer material having a layer of the cured product.

Among these, the introduction of a carboxy group into the reactive polycarboxylic acid compound (A) enhances adhesion to the substrate, so it is preferable to use it for coating plastic substrates or metal substrates.

Furthermore, it is also preferable to use the unreacted reactive polycarboxylic acid compound (A) as an alkaline water developable resist material composition by taking advantage of the characteristic that the unreacted reactive polycarboxylic acid compound (A) is soluble in an alkaline aqueous solution.

In the present invention, the resist material composition refers to an active energy ray sensitive composition in which a coating layer of the composition is formed on a substrate, and then the composition is partially irradiated with active energy rays such as ultraviolet rays, and drawing is performed by utilizing the difference in physical properties between the irradiated and unirradiated areas. Specifically, the composition is used for the purpose of removing the irradiated or unirradiated areas by some method, such as dissolving them with a solvent or an alkaline solution, and then performing drawing.

The active energy ray-curable resin composition, which is the resist material composition of the present invention, can be applied to various materials that can be patterned, and is particularly useful as a solder resist material and an interlayer insulating material for build-up construction methods, and can also be used as an optical waveguide in printed wiring boards, optoelectronic boards, optical boards, and other electrical, electronic, and optical substrates.

Particularly suitable applications include photosensitive films, photosensitive films with supports, insulating resin sheets such as prepregs, circuit boards (for laminates, multilayer printed wiring boards, etc.), solder resists, underfill materials, die bonding materials, semiconductor encapsulants, hole-filling resins, and component embedding resins, taking advantage of their excellent heat resistance and developability. In particular, because they exhibit excellent developability even at high pigment concentrations, they can be used in a wide range of applications requiring resin compositions, such as color resists and resist materials for color filters, particularly black matrix materials.

Furthermore, it can also be suitably used in resin compositions for insulating layers of multilayer printed wiring boards (multilayer printed wiring boards in which the cured product of a photosensitive resin composition serves as the insulating layer), resin compositions for interlayer insulating layers (multilayer printed wiring boards in which the cured product of a photosensitive resin composition serves as the interlayer insulating layer), and resin compositions for plating (multilayer printed wiring boards in which plating is formed on the cured product of a photosensitive resin composition).

Patterning using the active energy ray curable resin composition of the present invention can be carried out, for example, as follows. The curable resin composition of the present invention is applied to a substrate in a thickness of 0.1 to 200 μm by a method such as screen printing, spraying, roll coating, electrostatic coating, curtain coating, or spin coating, and the coating film is dried at a temperature of usually 50 to 110° C., preferably 60 to 100° C., to form a coating film. Thereafter, the coating film is directly or indirectly irradiated with high energy rays such as ultraviolet rays through a photomask on which an exposure pattern has been formed, usually at an intensity of about 10 to 2000 mJ/cm ² , and a desired pattern can be obtained using a developing solution described later, for example, by spraying, vibration immersion, paddle, brushing, or the like.

The alkaline aqueous solution used in the above development may be an inorganic alkaline aqueous solution such as potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, sodium phosphate, or potassium phosphate, or an organic alkaline aqueous solution such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide, monoethanolamine, diethanolamine, or triethanolamine. This aqueous solution may further contain an organic solvent, a buffer, a complexing agent, a dye, or a pigment.

In addition, it is particularly suitable for use in dry films that require mechanical strength before the curing reaction due to active energy rays. That is, because the balance between the hydroxyl groups and the epoxy groups in the epoxy resin (a) used in the present invention is within a specific range, the reactive polycarboxylic acid compound (A) of the present invention can exhibit good developability despite its relatively high molecular weight.

There are no particular limitations on the method for forming the film, but any of a variety of coating methods can be used, including gravure and other intaglio printing methods, flexography and other letterpress printing methods, silk screen and other screen printing methods, offset and other planographic printing methods, and methods using a roll coater, knife coater, die coater, curtain coater, spin coater, etc.

The cured product of the active energy ray-curable resin composition of the present invention refers to the product obtained by irradiating the active energy ray-curable resin composition of the present invention with active energy rays and curing it.

An article overcoated with the active energy ray-curable resin composition of the present invention refers to a material having at least two layers obtained by forming a film on a substrate using the active energy ray-curable resin composition of the present invention and curing it.

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In the examples, % indicates % by mass unless otherwise specified.

The softening point, epoxy equivalent, and acid value were measured under the following conditions.
1) Epoxy equivalent: Measured according to a method in accordance with JIS K7236:2001.
2) Softening point: Measured according to a method in accordance with JIS K7234:1986.
3) Acid value: Measured according to a method in accordance with JIS K0070:1992.
4) The measurement conditions for GPC are as follows:
Model: TOSOH HLC-8220GPC
Column: Super HZM-N
Eluent: THF (tetrahydrofuran); 0.35 ml/min, 40° C.
Detector: RI (differential refractometer)
Molecular weight standards: polystyrene

Synthesis Examples 1 to 3: Synthesis of reactive epoxy carboxylate compound (d) 205 g of NC-3500 (manufactured by Nippon Kayaku Co., Ltd., softening point 70° C., epoxy equivalent 205 g/eq.), acrylic acid (AA) or methacrylic acid (MAA) as carboxylic acid compound (b) in the amount shown in Table 1, and dimethylolpropionic acid (hereinafter abbreviated as "DMPA") as compound (c) in the amount shown in Table 1 were added. 3 g of triphenylphosphine as catalyst and propylene glycol monomethyl ether monoacetate as solvent were added so that the solid content was 80 mass%, and the mixture was reacted at 100° C. for 24 hours to obtain a reactive epoxy carboxylate compound (d) solution.

(Example 1, Comparative Example 1): Preparation of reactive polycarboxylic acid compound (A) To 200 g of the obtained reactive epoxy carboxylate compound (d) solution, a compound shown in Table 2 as a polybasic acid anhydride (e), in an amount (g), and propylene glycol monomethyl ether monoacetate as a solvent were added so that the solid content was 65%, and the mixture was 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: mgKOH/g) of the obtained reactive polycarboxylic acid compound (A) is shown in Table 2. The solid acid value (mgKOH/g) was measured as a solution and converted to a value in terms of solid content.

HTMA: 1,2,4-cyclohexanetricarboxylic acid-1,2-anhydride, manufactured by Mitsubishi Gas Chemical Company, Inc.
NTA: norbornane tricarboxylic anhydride, synthetic product as described in Japanese Patent No. 5532123 THPA: 1,2,3,6-tetrahydrophthalic anhydride, manufactured by New Japan Chemical Co., Ltd. SA: Rikacid SA succinic anhydride, manufactured by New Japan Chemical Co., Ltd.

(Example 2 and Comparative Example 2): Preparation of resist material composition 54.44 g of the reactive polycarboxylic acid compound (A) obtained in Example 1 and Comparative Example 1, 3.54 g of HX-220 (trade name: diacrylate monomer manufactured by Nippon Kayaku Co., Ltd.) as another reactive compound (B), 4.72 g of Irgacure 907 (manufactured by Ciba Specialty Chemicals) and 0.47 g of Kayacure DETX-S (manufactured by Nippon Kayaku Co., Ltd.) as photopolymerization initiators, 14.83 g of NC-3000 (manufactured by Nippon Kayaku Co., Ltd.) as a curing agent component, 1.05 g of melamine as a heat curing catalyst, and 20.95 g of methyl ethyl ketone as a concentration adjusting solvent were added, and the mixture was kneaded and uniformly dispersed using a bead mill to obtain a resist material resin composition.
The obtained composition was uniformly applied by roll coating onto a copper foil film serving as a support film, and passed through a hot air drying oven at a temperature of 70° C. to form a resin layer having a thickness of 30 μm. Thereafter, spray development was performed using a 1% aqueous sodium carbonate solution, and the time required for complete development, the so-called break time, was used to evaluate the developability (unit: seconds).

The above results show that the resist material composition using the reactive polycarboxylic acid compound (A) of the present invention has better developability than the compositions using the comparative reactive polycarboxylic acid compounds.

(Example 3 and Comparative Example 3): Evaluation of heat resistance 8 g of the reactive polycarboxylic acid compound (A) obtained in Example 1 and Comparative Example 1, 0.24 g of Irgacure 907 (manufactured by Ciba Specialty Chemicals) and 0.01 g of Kayacure DETX-S (manufactured by Nippon Kayaku Co., Ltd.) as photopolymerization initiators, 0.403 g of NC-3000 (manufactured by Nippon Kayaku Co., Ltd.) as hardener components, 0.017 g of triphenylphosphine and 0.446 g of propylene glycol monomethyl ether monoacetate as heat curing catalysts were added, and the mixture was uniformly applied to a polyimide film, passed through a hot air drying oven at a temperature of 80°C, and a resin layer having a thickness of 20 μm was formed. The film was then exposed to ultraviolet light using an ultraviolet light exposure device (Oak Manufacturing Co., Ltd., model HMW-680GW) to obtain a cured product. The prepared cured product was cut into a width of 5 mm. Thereafter, the sample was set in a viscoelasticity measuring device RSA-G2 manufactured by TA instruments, and tan δ was measured in an air atmosphere at a frequency of 10 Hz and a temperature rise rate of 2° C./min. The temperature at the maximum value of tan δ was taken as Tg.

The above results show that the active energy ray-curable resin composition using the reactive polycarboxylic acid compound (A) of the present invention has superior heat resistance compared to the comparative resin composition.

(Example 4 and Comparative Example 4): Evaluation of pigment dispersibility 20 g of the reactive polycarboxylic acid compound (A) obtained in Example 1 and Comparative Example 1, 5.0 g of DPHA (trade name: acrylate monomer manufactured by Nippon Kayaku Co., Ltd.) as another reactive compound (B), 10 g of propylene glycol monomethyl ether acetate as an organic solvent, and 15 g or 10 g of Mitsubishi carbon black MA-100 as a coloring pigment were added and stirred. Further, 35 g of glass beads were added, and dispersion was performed for 1 hour using a paint shaker. The dispersion liquid after dispersion was applied onto a polyethylene terephthalate film using a wire bar coater #2, and dried for 10 minutes using a hot air dryer at 80°C. The gloss of the coating surface after drying was measured using a 60° reflection gloss meter (HORIBA IG-331 gloss meter) to evaluate the dispersibility of the carbon black. The results are shown in Table 5. The higher the gloss value, the better the pigment dispersibility.

From the above results, the coating film obtained from the resin composition containing the reactive polycarboxylic acid compound (A) obtained in Example 1 did not change in gloss value even when the content of the color pigment was high. It can be confirmed that the pigment dispersibility of the reactive polycarboxylic acid compound (A) of the present invention is excellent and does not depend on the content of the color pigment, even though the developability and heat resistance are improved.

From the above, the cured product of the active energy ray curable resin composition using the reactive polycarboxylic acid compound (A) of the present invention has excellent heat resistance and can be finely developed with an alkali, so that it is suitable for molding materials, film-forming materials, and resist materials. In particular, since it exhibits good developability even at a high pigment concentration, it is suitable for color resists, resist materials for color filters, and especially black matrix materials.

Claims (9)

An active energy ray-reactive polycarboxylic acid compound (A) is obtained by reacting an epoxy resin (a) represented by the following formula (1) with only a carboxylic acid compound (b) having both a (meth)acrylic group and a carboxy group in one molecule, or with only a carboxylic acid compound (b) having both a (meth)acrylic group and a carboxy group in one molecule and a compound (c) having both a hydroxyl group and a carboxy group in one molecule, to obtain an active energy ray-reactive epoxy carboxylate compound (d), which is obtained by reacting the epoxy resin (a) represented by the following formula (1) with a polybasic acid anhydride (e) represented by the following formula (2).

(In the formula, each Ar is independently either (I) or (II), and the molar ratio of (I) to (II) is (I)/(II)=1 to 3. G represents a glycidyl group. n represents the average number of repetitions and is a positive number in the range of 0<n≦5.)

(In formula (2), each R ₁ independently represents a hydrogen atom or a methyl group , and m represents an integer of 1 to 3.) An active energy ray-curable resin composition containing the active energy ray-reactive polycarboxylic acid compound (A) according to claim 1. The active energy ray curable resin composition according to claim 2, which contains an active energy ray reactive compound (B) other than the active energy ray reactive polycarboxylic acid compound (A). The active energy ray-curable resin composition according to claim 2 or claim 3, which contains a photopolymerization initiator. The active energy ray-curable resin composition according to any one of claims 2 to 4, which is a molding material. The active energy ray-curable resin composition according to any one of claims 2 to 4, which is a film-forming material. The active energy ray-curable resin composition according to any one of claims 2 to 4, which is a resist material composition. A cured product of the active energy ray-curable resin composition according to any one of claims 2 to 7. An article overcoated with a cured product of the active energy ray-curable resin composition according to claim 8.