JP2009155360A - Photosensitive resin and resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive resin composition which is excellent in basic properties such as developability and curability and is also excellent in both uncured film properties (tack-free properties, developability) and cured film physical properties (water resistance, flex resistance). <P>SOLUTION: An epoxy resin, a phenol compound having an alcoholic hydroxy group, and an unsaturated monobasic acid are allowed to react with each other to obtain a curable resin, which is allowed to react with a polybasic acid anhydride to obtain a photosensitive resin. The photosensitive resin is obtained by using a difunctional epoxy resin as the epoxy resin and using a polybasic acid anhydride having a plurality of acid anhydride groups in a molecule as at least part of the polybasic acid anhydride. The photosensitive resin composition comprises the photosensitive resin and a photopolymerization initiator. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a photosensitive resin composition that can be photocured to form an image.

  Photosensitive resin compositions for image formation are capable of microfabrication by applying the principle of photolithography (photolithography) and can form images by giving cured products with excellent physical properties. Are widely used for various resist materials and printing plates. The photosensitive resin composition for image formation includes a solvent development type and an alkali development type. In recent years, an alkali development type that can be developed with a dilute weak alkaline aqueous solution has become mainstream from the viewpoint of environmental measures.

  When the photosensitive resin composition for image formation is used in a photographic process (photolithography), first, the resin composition is applied onto a substrate, followed by heat drying to form a coating film. A series of steps is employed in which a film for pattern formation is attached to the coating film, exposed and developed. In such a process, if adhesiveness remains in the coating film after drying by heating, a part of the resist adheres to the pattern forming film after peeling, and an accurate pattern cannot be reproduced. There was a problem that the forming film could not be peeled off. For this reason, although photosensitivity is important, tack-free property after coating film formation is also an important required characteristic of the photosensitive resin composition for image formation. In addition to developability, the photocured coating film is required to have properties relating to long-term reliability such as heat resistance, water resistance and moisture resistance.

  A carboxyl group-containing vinyl ester in which a carboxyl group is introduced by reacting an acid anhydride with a vinyl ester (epoxy acrylate) obtained by reacting an epoxy resin with (meth) acrylic acid is known to satisfy the above characteristics to some extent. It has been. The present applicant has been continuously researching and developing a carboxyl group-containing vinyl ester photosensitive resin composition and has made many inventions (for example, Patent Documents 1 to 3).

  The carboxyl group-containing vinyl ester satisfies the conflicting properties such as tack-free property, photosensitivity, and developability in a well-balanced manner, and has relatively good important properties such as heat resistance and water resistance required for the cured product. . However, with the advancement of technology, higher level characteristics such as bending resistance have been demanded.

  This bending resistance is, for example, a characteristic that, after a coating film is formed on a thin film substrate and photocured, it does not crack even if the coating film is folded outward. In order to improve the bending resistance, it is conceivable to lower the Tg of the photosensitive resin to make the resin softer. However, the present inventors have investigated that even if the bending resistance is improved, In some cases, the developability of the pre-cured coating film was lowered.

JP 2007-153978 A JP 2007-199533 A JP 2007-206421 A

  In consideration of the above-mentioned conventional techniques, the present invention is excellent in basic properties such as developability and curability, has both tack-free properties of the uncured coating film and bending resistance of the cured coating film, and is excellent in water resistance. It is an object of the present invention to provide a photosensitive resin composition.

  The photosensitive resin of the present invention that has solved the above problems is obtained by reacting a polybasic acid anhydride with a curable resin obtained by reacting an epoxy resin, a phenolic compound having an alcoholic hydroxyl group, and an unsaturated monobasic acid. A photosensitive resin obtained by using a bifunctional epoxy resin as the epoxy resin and having a plurality of acid anhydride groups in one molecule as at least a part of the polybasic acid anhydride. And

  The photosensitive resin preferably has an acid value of 20 to 70 mg KOH / g, and the polybasic acid anhydride having a plurality of acid anhydride units in one molecule is preferably a tetrabasic acid dianhydride. The present invention also includes a photosensitive resin composition containing the photosensitive resin and a photopolymerization initiator, and a cured product obtained by curing the photosensitive resin composition.

The photosensitive resin composition of the present invention is a polybasic acid anhydride having a plurality of acid anhydride groups in one molecule by reacting a phenol compound having an alcoholic hydroxyl group with a bifunctional epoxy resin as a starting material. By extending the chain, the coating film was not made brittle and the bending resistance was improved.

  In addition, a polybasic acid anhydride having a plurality of acid anhydride groups in one molecule extends the chain while introducing a carboxyl group, so that tack-free property before photocuring can be maintained, and alkali development is possible even at a low acid value. Since it was good, it was also found that the cured coating film was excellent in water resistance.

  Therefore, the photosensitive resin composition of the present invention is an alkali-developable photosensitive resin composition for image formation, such as, for example, an etching resist, an electroless plating resist, a build-up printed wiring board insulating layer, a printing plate making, Can be suitably used for various applications such as for producing liquid crystal display panels such as a color filter protective film, a color filter, a black matrix, and a photo spacer.

The photosensitive resin which is an essential component of the photosensitive resin composition of the present invention includes a bifunctional epoxy resin, a phenol compound having an alcoholic hydroxyl group, an unsaturated monobasic acid, and a plurality of acid anhydride groups in one molecule. It is synthesized from a polybasic acid anhydride having. That is, a polybasic acid anhydride having a plurality of acid anhydride groups in one molecule for a curable resin obtained from a bifunctional epoxy resin, a phenolic compound having an alcoholic hydroxyl group, and an unsaturated monobasic acid. By reacting, a carboxyl group is introduced while chain-extending the curable resin to obtain an alkali development type photosensitive resin.

  By reacting a phenolic compound having an alcoholic hydroxyl group, a polybasic acid anhydride having a plurality of acid anhydride groups in one molecule is introduced by introducing an alcoholic hydroxyl group at the molecular chain end. Extend chain. As a result, tack-free property before curing, alkali developability, water resistance of the cured product, and flexibility could be improved in a balanced manner.

  The bifunctional epoxy resin that is the starting material of the present invention may be an epoxy compound having two epoxy groups in one molecule, and a known epoxy resin having two epoxy groups in one molecule can be used. Bisphenol type epoxy resins such as bisphenol A type, tetrabromobisphenol A type, bisphenol S type and bisphenol F type; alicyclic epoxy resin; diglycidyl ester type epoxy resin; diglycidyl ether type epoxy resin of polyhydric alcohol, especially Polyalkylene glycols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol, or dihydric alcohols obtained by adding alkylene oxide to a bisphenol compound that is a precursor of the bisphenol-type epoxy resin; Diglycidyl ether type epoxy resin obtained by reacting a Roruhidorin; diglycidyl amine type epoxy resins; biphenyl type epoxy resins; bifunctional epoxy resins such as phenylene type epoxy resins.

  Moreover, what extended | stretched the chain | strand by combining two or more molecules of these epoxy resins by reaction with chain extenders, such as a polybasic acid, a polyphenol compound, a polyfunctional amino compound, or a polyvalent thiol can also be used.

  Among these, bisphenol-type epoxy resins, biphenyl-type epoxy resins, and phenylene-type epoxy resins are preferable because the cured product properties are particularly good.

  In the present invention, a known epoxy resin having an average of 3 or more epoxy groups in one molecule may be used in combination as an epoxy resin as a starting material.

  As such an epoxy resin, any known epoxy resin having 3 or more epoxy groups in one molecule can be used without particular limitation, and a polyfunctional glycidylamine resin such as tetraglycidylaminodiphenylmethane; Polyfunctional glycidyl ether resins such as tetraphenyl glycidyl ether ethane; phenol novolac type epoxy resins and cresol novolac type epoxy resins; phenolic compounds such as phenol, o-cresol, m-cresol, naphthol, and aroma having a phenolic hydroxyl group Reaction product of polyphenol compound obtained by condensation reaction with aromatic aldehyde and epichlorohydrin; polyphenol compound obtained by addition reaction of phenol compound and diolefin compound such as divinylbenzene and dicyclopentadiene And Nord compound, reaction product of epichlorohydrin; 4-vinylcyclohexene-1-opening polymerization of oxide what was epoxidized with peracetic acid; epoxy resin having a heterocyclic ring such as triglycidyl isocyanurate; and the like.

  The phenolic compound having an alcoholic hydroxyl group of the present invention is a compound in which an alcoholic hydroxyl group is indirectly bonded to the aromatic ring of the phenolic compound, and has a plurality of alcoholic hydroxyl groups or phenolic hydroxyl groups. Also good. In addition to the alcoholic hydroxyl group and phenolic hydroxyl group, other substituents may be included, and naphthol having an alcoholic hydroxyl group is also included.

  Specific examples of such a phenol compound include (bis) hydroxymethylphenol, (bis) hydroxymethylcresol, hydroxymethyl-di-t-butylphenol, p-hydroxyphenyl-2-ethanol, p-hydroxyphenyl-2- Propanol, p-hydroxyphenyl-3-propanol, p-hydroxyphenyl-2-butanol, p-hydroxyphenyl-3-butanol, p-hydroxyphenyl-4-butanol, 4- (4-hydroxy-3-methoxyphenyl) Hydroxyalkylphenol or hydroxyalkylcresol such as 2-butanol, 4- (3-hydroxydecyl) -2-methoxyphenol, hydroxyethylcresol; hydroxybenzoic acid, hydroxyphenylbenzoic acid, hydride Esterified products of carboxyl group-containing phenolic compounds such as xylphenoxybenzoic acid and ethylene glycol, propylene glycol, glycerol, etc .; monoethylene oxide adducts of bisphenol, monopropylene oxide adducts of bisphenol, etc., one of these Or 2 or more types can be used.

  Unsaturated monobasic acids are used to introduce radically polymerizable double bonds into the resin. An unsaturated monobasic acid is a monobasic acid having one carboxyl group and one or more radically polymerizable unsaturated bonds. Specific examples include acrylic acid, methacrylic acid, crotonic acid, cinnamic acid, β-acryloxypropionic acid, hydroxyalkyl (meth) acrylate and dibasic acid having one hydroxyl group and one (meth) acryloyl group. A reaction product with an anhydride, a reaction product of a polyfunctional (meth) acrylate having one hydroxyl group and two or more (meth) acryloyl groups, and a dibasic acid anhydride, and the like.

  Among these, those having a (meth) acryloyl group such as acrylic acid and methacrylic acid are preferable. These can use 1 type (s) or 2 or more types.

  Reaction of epoxy resin with phenolic compound having alcoholic hydroxyl group and unsaturated monobasic acid is a method of reacting epoxy resin with unsaturated monobasic acid and then reacting phenolic compound with alcoholic hydroxyl group, epoxy resin A method of simultaneously reacting an unsaturated monobasic acid and a phenolic compound having an alcoholic hydroxyl group, a method of reacting an epoxy resin and a phenolic compound having an alcoholic hydroxyl group, and then reacting with an unsaturated monobasic acid, etc. Yes, either may be adopted.

  The phenolic compound having an alcoholic hydroxyl group is 0.01 mol or more and 0.6 mol or less (more preferably 0.05 mol or more and 0.5 mol or less) with respect to one chemical equivalent of epoxy group in the epoxy resin. The unsaturated monobasic acid is preferably reacted in an amount of 0.4 mol or more and 0.99 mol or less (more preferably 0.5 mol or more and 0.95 mol or less). Moreover, as a sum total of a phenol compound and unsaturated monobasic acid, it is preferable to set it as 0.8-1.1 mol with respect to 1 chemical equivalent of epoxy groups.

  By making the phenol compound 0.01 mol or more, the flexibility imparting effect is further exhibited, and by making the unsaturated monobasic acid 0.4 mol or more, better curability is obtained. By making this total amount 1.1 mol or less, unreacted phenolic compounds and unsaturated monobasic acids can be reduced, and these low molecular weight compounds do not cause deterioration in the properties of the cured product.

  As described above, the reaction of the phenolic compound having an alcoholic hydroxyl group and the unsaturated monobasic acid with respect to the epoxy resin may be carried out either first or simultaneously.

  These reactions are carried out in the presence or absence of a diluent such as a radically polymerizable monomer and a solvent, which will be described later, a polymerization inhibitor such as hydroquinone and oxygen, a tertiary amine such as triethylamine, a triethylbenzylammonium chloride and the like. Reactions of quaternary ammonium salts, imidazole compounds such as 2-ethyl-4-methylimidazole, phosphorus compounds such as triphenylphosphine and tetraphenylphosphonium bromide, metal organic acid salts or inorganic acid salts (lithium chloride, etc.) or chelate compounds What is necessary is just to make it react at 60-150 degreeC in the coexistence of a catalyst, Preferably it is 80-140 degreeC.

  By this reaction, a curable resin before chain extension by a polybasic acid anhydride having a plurality of acid anhydride groups in one molecule is obtained. This curable resin is introduced by a phenol compound having an alcoholic hydroxyl group. And an alcoholic hydroxyl group produced by ring opening of an epoxy group in a raw material epoxy resin by a phenol compound or an unsaturated monobasic acid having an alcoholic hydroxyl group. By reacting these hydroxyl groups with a polybasic acid anhydride having a plurality of acid anhydride groups in one molecule, a carboxyl group can be introduced while chain-extending the curable resin. Since the obtained carboxyl group-containing photosensitive resin can be alkali-developed, it can be used as an alkali-developable photosensitive resin for image formation or the like.

  Examples of the polybasic acid anhydride having a plurality of acid anhydride groups in one molecule include biphenyltetracarboxylic dianhydride, diphenylethertetracarboxylic dianhydride, butanetetracarboxylic dianhydride, cyclopentanetetracarboxylic acid diacid. Aliphatic or aromatic tetrabasic acid dianhydrides such as anhydride, pyromellitic dianhydride, benzophenone tetracarboxylic dianhydride, diphenylsulfone tetracarboxylic dianhydride, and the like, one or two of these More than seeds can be used.

  The acid value of the photosensitive resin in the present invention is preferably 20 mgKOH / g or more and 70 mgKOH / g or less. More preferably, they are 30 mgKOH / g or more and 65 mgKOH / g or less, More preferably, they are 40 mgKOH / g or more and 60 mgKOH / g or less. By setting it as this range, tack-free property before curing, alkali developability, and water resistance of the cured product can be improved in a balanced manner.

  In addition, the double bond equivalent (molecular weight per chemical equivalent of radical polymerizable double bond) of the photosensitive resin in the present invention is preferably 400 g / eq or more. Since the distance between the crosslinking points is appropriate, flexibility is imparted to the cured product and bending resistance is improved. A more preferred lower limit of the double bond equivalent is 450 g / eq, and a more preferred lower limit is 500 g / eq. The upper limit of the double bond equivalent is preferably 7000 g / eq. When the double bond equivalent is 7000 g / eq or less, sufficient fluidity can be obtained in the presence or absence of a diluent such as a radically polymerizable compound and a solvent described later, and handling during production and coating operations Is easy. A more preferred upper limit is 6000 g / eq, and a more preferred upper limit is 5000 g / eq.

  In the present invention, in order to make the acid value and double bond equivalent of the photosensitive resin within the above-mentioned preferable ranges, a hydroxyl group that the curable resin has a polybasic acid anhydride having a plurality of acid anhydride groups in one molecule. It is made to react so that it may become 0.1-10 mol with respect to 1 chemical equivalent of 0.01-0.5 mol with respect to 1 chemical equivalent of group, and the alcoholic hydroxyl group introduced with the phenolic compound which has an alcoholic hydroxyl group. It is preferable.

  In the present invention, in addition to the polybasic acid anhydride having a plurality of acid anhydride groups in one molecule, a dibasic acid anhydride may be used in combination. Thus, the carboxyl group can be introduced without extending the chain more than necessary (without increasing the molecular weight too much). Such dibasic acid anhydrides include phthalic anhydride, succinic anhydride, octenyl succinic anhydride, pentadodecenyl succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, 3 , 6-endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, tetrabromophthalic anhydride, trimellitic acid and the like.

  These are 50 mol% or less, more preferably 40 mol% or less, based on 100 mol% of the total polybasic acid anhydride, which is a combination of the polybasic acid anhydride having a plurality of acid anhydride groups in one molecule and the dibasic acid anhydride. By setting the amount to be used at a mol% or less, the developability can be supplemented without impairing the tack-free property maintaining effect.

  This reaction is usually carried out at 50 to 130 ° C. in the presence of a polymerization inhibitor such as hydroquinone or oxygen in the presence or absence of a diluent such as a radical polymerizable monomer or a solvent described later. At this time, if necessary, a tertiary amine such as triethylamine, a quaternary ammonium salt such as triethylbenzylammonium chloride, a metal salt such as lithium chloride, and the like may be added as a catalyst.

  The photosensitive resin of the present invention is obtained by a polybasic acid anhydride having a plurality of acid anhydride groups in one molecule via a hydroxyl group introduced at the terminal of a bifunctional epoxy resin through the steps described so far. It mainly contains chain-extended structures. Some starting epoxy resins also have alcoholic hydroxyl groups, and there are also hydroxyl groups that are formed by ring-opening by reaction of epoxy groups with unsaturated monobasic acids or phenolic compounds. This is because the reaction between the group and the acid anhydride group is hindered due to steric hindrance, and the reaction between the alcoholic hydroxyl group derived from the phenol compound and the acid anhydride group is given priority.

  By having such a structure, unsaturated double bonds are located at both ends of the molecular chain extended. Therefore, flexibility is imparted to the cured product and bending resistance is improved.

  When the photosensitive resin of the present invention is a photosensitive resin composition containing a photopolymerization initiator, radical polymerization by light becomes possible.

  Known photopolymerization initiators can be used such as benzoin such as benzoin, benzoin methyl ether, benzoin ethyl ether and alkyl ethers thereof; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone. Acetophenones such as 4- (1-t-butyldioxy-1-methylethyl) acetophenone; anthraquinones such as 2-methylanthraquinone, 2-amylanthraquinone, 2-t-butylanthraquinone, 1-chloroanthraquinone; 2,4 -Thioxanthones such as dimethylthioxanthone, 2,4-diisopropylthioxanthone and 2-chlorothioxanthone; Ketals such as acetophenone dimethyl ketal and benzyldimethyl ketal; Benzophenone, 4- (1- -Benzophenones such as butyldioxy-1-methylethyl) benzophenone and 3,3 ', 4,4'-tetrakis (t-butyldioxycarbonyl) benzophenone; 2-methyl-1- [4- (methylthio) phenyl]- Examples include 2-morpholino-propan-1-one and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1; acylphosphine oxides and xanthones.

  These photopolymerization initiators are used as one or a mixture of two or more, and are contained in an amount of 0.5 to 30 parts by mass with respect to 100 parts by mass in total of the photosensitive resin and the radically polymerizable compound described later. preferable. When the amount of the photopolymerization initiator is less than 0.5 parts by mass, it is necessary to increase the light irradiation time or it is difficult for polymerization to occur even if light irradiation is performed, so that an appropriate surface hardness can be obtained. Disappear. In addition, even if it mixes photopolymerization initiator exceeding 30 mass parts, there is no merit which uses it in large quantities.

  The photosensitive resin composition of the present invention may contain a radical polymerizable compound. Examples of the radical polymerizable compound include a radical polymerizable resin and a radical polymerizable monomer.

  As the radical polymerizable resin, unsaturated polyester, urethane acrylate, polyester acrylate, epoxy acrylate, or the like can be used. When these radical polymerizable resins are used as the radical polymerizable compound, in order to effectively exhibit the bending resistance improving effect and the like derived from the photosensitive resin of the present invention, the resin solid content (the photosensitive resin of the present invention and When the total amount of the radical polymerizable resin solid content) is 100 parts by mass, the radical polymerizable resin is preferably used at 90 parts by mass or less. A more preferable upper limit value is 80 parts by mass, and a further preferable upper limit value is 70 parts by mass.

  A radical polymerizable monomer can also be used as the radical polymerizable compound. Either a monofunctional monomer (one radical polymerizable double bond) or a polyfunctional monomer (two or more radical polymerizable double bonds) can be used. Since the radically polymerizable monomer is involved in photopolymerization, it can be used as a solvent for various reactions in addition to improving the properties of the resulting cured product, and can further adjust the viscosity of the photosensitive resin composition. . When using a radical polymerizable monomer, the preferable usage-amount is 300 mass parts or less (more preferably 100 mass parts or less) with respect to 100 mass parts of total amounts of the photosensitive resin of this invention and the said radical polymerizable resin.

  Specific examples of the radical polymerizable monomer include N-phenylmaleimide, N- (2-methylphenyl) maleimide, N- (4-methylphenyl) maleimide, N- (2,6-diethylphenyl) maleimide, N- ( 2-chlorophenyl) maleimide, N-methylmaleimide, N-ethylmaleimide, N-isopropylmaleimide, N-laurylmaleimide, N-cyclohexylmaleimide, N-phenylmethylmaleimide, N- (2,4,6-tribromophenyl) Maleimide, N- [3- (triethoxysilyl) propyl] maleimide, N-octadecenylmaleimide, N-dodecenylmaleimide, N- (2-methoxyphenyl) maleimide, N- (2,4,6 -Trichlorophenyl) maleimide, N- (4-hydroxyphenyl) maleimi N-substituted maleimide group-containing monomers such as N- (1-hydroxyphenyl) maleimide; styrene, α-methylstyrene, α-chlorostyrene, vinyltoluene, p-hydroxystyrene, divinylbenzene, diallyl phthalate, diallylbenzene Aromatic vinyl monomers such as phosphonate; vinyl ester monomers such as vinyl acetate and vinyl adipate; (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-hydroxy Ethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 4-hydroxymethyl (meth) acrylamide, pentaerythritol mono (meta) Acrylate, dipentaerythritol mono (meth) acrylate, trimethylolpropane mono (meth) acrylate, 1,6-hexanediol mono (meth) acrylate, glycerol mono (meth) acrylate, (di) ethylene glycol di (meth) acrylate, Propylene glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tris [2- (meth) (Acryloyloxyethyl) triazine, dendritic acrylate and other (meth) acrylic monomers; n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl (Hydroxy) alkyl vinyl (thio) ethers such as ether, isobutyl vinyl ether, n-hexyl vinyl ether, cyclohexyl vinyl ether, 2-ethylhexyl vinyl ether, 4-hydroxybutyl vinyl ether; 2- (vinyloxyethoxy) ethyl (meth) acrylate, ( 2- (isopropenoxyethoxyethoxy) ethyl (meth) acrylate, 2- (isopropenoxyethoxyethoxyethoxy) ethyl (meth) acrylate, 2- (isopropenoxyethoxyethoxyethoxyethoxy) ethyl (meth) acrylate, etc. A vinyl (thio) ether having a radical polymerizable double bond of the above; an acid anhydride group-containing monomer such as maleic anhydride, or a monomer obtained by ring-opening modification of an acid anhydride group with alcohols, amines, water, etc. Mer; N- Examples thereof include N-vinyl monomers such as vinylpyrrolidone and N-vinyloxazolidone; compounds having one or more double bonds capable of radical polymerization, such as allyl alcohol and triallyl cyanurate. These are suitably selected according to the use and required characteristics of the photosensitive resin composition, and can be used alone or in combination of two or more.

  From the viewpoint of workability when the composition of the present invention is applied to a substrate, a solvent may be blended in the composition. Solvents include hydrocarbons such as toluene and xylene; cellosolves such as cellosolve and butylcellosolve; carbitols such as carbitol and butylcarbitol; esters such as cellosolve acetate, carbitol acetate, and propylene glycol monomethyl ether acetate; methyl Examples thereof include ketones such as isobutyl ketone and methyl ethyl ketone; ethers such as diethylene glycol dimethyl ether. These solvents can be used singly or in combination of two or more, and are used in an appropriate amount so that the composition has an optimum viscosity during the coating operation.

  In the composition of the present invention, if necessary, fillers such as talc, clay, barium sulfate, coloring pigments, antifoaming agents, coupling agents, leveling agents, sensitizers, mold release agents, lubricants, You may add well-known additives, such as a plasticizer, antioxidant, a ultraviolet absorber, a flame retardant, a polymerization inhibitor, and a thickener. Further, various reinforcing fibers can be used as reinforcing fibers to form a fiber-reinforced composite material.

  When the photosensitive resin composition of the present invention is used for image formation, it is usually applied to a substrate by a known method, dried, exposed to obtain a cured coating film, and then an unexposed portion is treated with an alkaline aqueous solution. Then, alkali development is performed.

  Specific examples of alkalis that can be used for development include alkali metal compounds such as sodium carbonate, potassium carbonate, sodium hydroxide and potassium hydroxide; alkaline earth metal compounds such as calcium hydroxide; ammonia; monomethylamine and dimethylamine Water-soluble organic amines such as trimethylamine, monoethylamine, diethylamine, triethylamine, monopropylamine, dimethylpropylamine, monoethanolamine, diethanolamine, triethanolamine, ethylenediamine, diethylenetriamine, dimethylaminoethyl methacrylate, polyethyleneimine, These 1 type (s) or 2 or more types can be used.

  The photosensitive resin composition of the present invention can be used in the form of a dry film which is previously applied to a film of polyethylene terephthalate or the like and dried in addition to a method of directly applying a liquid resin to a substrate. In this case, a dry film may be laminated on a substrate, and the film may be peeled off before or after exposure.

  In addition, the CTP (Computer To Plate) system, which is frequently used in the printing plate making field, that is, without using a pattern forming film during exposure, laser light is directly scanned and exposed on the coating film using digitized data. The drawing method can be adopted.

Hereinafter, the present invention will be described in more detail by way of examples. However, the following examples are not intended to limit the present invention, and all modifications made without departing from the spirit of the present invention are within the technical scope of the present invention. Is included. In the following description, “part” represents “part by mass” and “%” represents “% by mass” unless otherwise specified.

Synthesis Example 1 (Example 1)
In a container equipped with a stirrer, a thermometer, a reflux condenser, and a gas introduction tube, 248 parts of “jER (registered trademark) 834” (manufactured by Japan Epoxy Resin; bisphenol A type epoxy resin: epoxy equivalent 248), 4- ( 4-hydroxy-3-methoxyphenyl) -2-butanol 58.9 parts, propylene glycol monomethyl ether acetate 94.3 parts, benzyltriethylammonium chloride 0.4 parts were charged and reacted at 120 ° C. for 3 hours to determine the epoxy group. Thus, the completion of the reaction between the epoxy group and the phenolic hydroxyl group was confirmed.

  Next, 61.1 parts of methacrylic acid, 0.8 part of methylhydroquinone and 1.1 parts of triphenylphosphine were added and reacted at 120 ° C. for 20 hours to confirm that the acid value of the reaction product was 3. .

  Further, 94.3 parts of propylene glycol monomethyl ether acetate and 32.7 parts of pyromellitic dianhydride were added and reacted at 110 ° C. for 3 hours to contain 68% of photosensitive resin A-1 having an acid value of 45 mg KOH / g. A dipropylene glycol monomethyl ether acetate solution was obtained.

Synthesis Example 2 (Example 2)
In a vessel equipped with a stirrer, thermometer, reflux condenser, and gas introduction tube, 248 parts of the above-mentioned “jER (registered trademark) 834”, 41.5 parts of p-hydroxyphenyl-2-ethanol, propylene glycol monomethyl ether acetate 90 .2 parts and 0.4 parts of benzyltriethylammonium chloride were charged, reacted at 120 ° C. for 3 hours, and the completion of the reaction between the epoxy group and the phenolic hydroxyl group was confirmed by epoxy group determination.

  Next, 61.1 parts of methacrylic acid, 0.8 part of methylhydroquinone and 1.1 parts of triphenylphosphine were added and reacted at 120 ° C. for 20 hours to confirm that the acid value of the reaction product was 4. .

  Further, 90.2 parts of propylene glycol monomethyl ether acetate and 32.7 parts of pyromellitic dianhydride were added and reacted at 110 ° C. for 3 hours to contain 68% of photosensitive resin A-2 having an acid value of 47 mg KOH / g. A dipropylene glycol monomethyl ether acetate solution was obtained.

Synthesis Example 3 (Example 3)
In a vessel equipped with a stirrer, a thermometer, a reflux condenser, and a gas introduction tube, 248 parts of the above-mentioned “jER (registered trademark) 834”, 55.3 parts of p-hydroxyphenyl-2-ethanol, propylene glycol monomethyl ether acetate 94 And 0.4 part of benzyltriethylammonium chloride were added and reacted at 120 ° C. for 3 hours, and the completion of the reaction between the epoxy group and the phenolic hydroxyl group was confirmed by epoxy group determination.

  Next, 52.5 parts of methacrylic acid, 0.8 part of methylhydroquinone and 1.1 parts of triphenylphosphine were added and reacted at 120 ° C. for 20 hours to confirm that the acid value of the reaction product was 3. .

  Further, 94 parts of propylene glycol monomethyl ether acetate and 43.6 parts of pyromellitic dianhydride were added and reacted at 110 ° C. for 3 hours to obtain dipropylene containing 68% of photosensitive resin A-3 having an acid value of 59 mg KOH / g. A glycol monomethyl ether acetate solution was obtained.

Synthesis Example 4 (Example 4)
In a vessel equipped with a stirrer, thermometer, reflux condenser, and gas introduction tube, 248 parts of the above-mentioned “jER (registered trademark) 834”, 41.5 parts of p-hydroxyphenyl-2-ethanol, propylene glycol monomethyl ether acetate 95 0.1 part and 0.4 part of benzyltriethylammonium chloride were charged and reacted at 120 ° C. for 3 hours, and the completion of the reaction between the epoxy group and the phenolic hydroxyl group was confirmed by epoxy group determination.

  Next, 61.1 parts of methacrylic acid, 0.8 part of methylhydroquinone and 1.1 parts of triphenylphosphine were added and reacted at 120 ° C. for 20 hours to confirm that the acid value of the reaction product was 4. .

  Further, 95.1 parts of propylene glycol monomethyl ether acetate and 53.7 parts of diphenylsulfonetetracarboxylic dianhydride were added and reacted at 110 ° C. for 3 hours to obtain 68 mg of photosensitive resin A-4 having an acid value of 45 mgKOH / g. % Dipropylene glycol monomethyl ether acetate solution was obtained.

Synthesis Example 5 (Comparative Example 1)
In a vessel equipped with a stirrer, a thermometer, a reflux condenser, and a gas introduction tube, 248 parts of the above-mentioned “jER (registered trademark) 834”, 91.6 parts of propylene glycol monomethyl ether acetate, 87 parts of methacrylic acid, 0. 8 parts and 1 part of triphenylphosphine were charged and reacted at 120 ° C. for 20 hours to confirm that the acid value of the reaction product was 5.
Next, 91.6 parts of propylene glycol monomethyl ether acetate, 54.5 parts of pyromellitic dianhydride and 0.3 part of benzyltriethylammonium chloride were added and reacted at 110 ° C. for 6 hours to compare the acid value of 79 mgKOH / g. Dipropylene glycol monomethyl ether acetate solution containing 68% of photosensitive resin B-1 was obtained.

Synthesis Example 6 (Comparative Example 2)
In a vessel equipped with a stirrer, a thermometer, a reflux condenser, and a gas introduction pipe, 232 parts of “Epototo (registered trademark) YD-901” (manufactured by Tohto Kasei Co., Ltd .; bisphenol A type epoxy resin: epoxy equivalent 463.9), 69.9 parts of propylene glycol monomethyl ether acetate, 43.5 parts of methacrylic acid, 0.6 part of methylhydroquinone and 0.8 part of triphenylphosphine were added and reacted at 120 ° C. for 20 hours. The acid value of the reaction product was 3 It was confirmed that it became.

  Next, 69.9 parts of propylene glycol monomethyl ether acetate, 21.8 parts of pyromellitic dianhydride and 0.3 part of benzyltriethylammonium chloride were added and reacted at 110 ° C. for 6 hours to compare the acid value of 41 mgKOH / g. Dipropylene glycol monomethyl ether acetate solution containing 68% of photosensitive resin B-1 was obtained.

Synthesis Example 7 (Comparative Example 3)
In a container equipped with a stirrer, a thermometer, a reflux condenser, and a gas introduction pipe, 200 parts of “Epototo (registered trademark) YDCN-703” (manufactured by Toto Kasei Co., Ltd .; cresol novolac type epoxy resin: epoxy equivalent 200), p- Charge 41.5 parts of hydroxyphenyl-2-ethanol, 89.1 parts of propylene glycol monomethyl ether acetate and 0.3 part of benzyltriethylammonium chloride, react at 120 ° C. for 5 hours, and determine epoxy group and phenolic hydroxyl by epoxy group determination. The completion of the reaction with the group was confirmed. Next, 61.1 parts of methacrylic acid, 0.8 part of methylhydroquinone and 0.9 part of triphenylphosphine were added and reacted at 120 ° C. for 20 hours to confirm that the acid value of the reaction product was 3. . Further, 89.1 parts of propylene glycol monomethyl ether acetate and 76.1 parts of tetrahydrophthalic anhydride were added and reacted at 110 ° C. for 4 hours to contain 68% of comparative photosensitive resin B-3 having an acid value of 78 mgKOH / g. A dipropylene glycol monomethyl ether acetate solution was obtained.

[Preparation of photosensitive resin composition]
100 parts of each photosensitive resin solution obtained above, 10 parts of DPHA (manufactured by Nippon Kayaku Co., Ltd .; dipentaerythritol hexaacrylate), “Irgacure (registered trademark) 907” (Ciba Japan) as a photopolymerization initiator 5 parts of 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropen-1-one) were mixed to obtain a photosensitive resin composition. The following various characteristic evaluations are performed, and the evaluation results are shown in Table 1.

[Tack-free]
Each resin composition was applied to a thickness of 20 to 30 μm on a 1.6 mm thick copper-clad laminate that had been degreased and washed, and dried at 80 ° C. for 30 minutes in a hot air circulating drying oven to obtain a coating film. It was. The tack free property of this coating film was evaluated according to the following criteria by finger touch.
○: Tack is not recognized at all Δ: Slightly tack is recognized ×: Tack is remarkably recognized

[Developability]
A dry coating film was formed in the same manner as the tack-free evaluation. Subsequently, development was performed at 30 ° C. for 60 seconds using a 1% aqueous sodium carbonate solution, and the presence of the remaining resin coating film was visually evaluated according to the following criteria.
○: Good developability (no deposit on the copper surface)
X: Poor developability (a deposit remains remarkably on the copper surface or is not developed at all).

[Photocurability]
A dry coating film was formed in the same manner as the tack-free evaluation, and the coating film was cured by irradiating a light amount of 500 mJ / cm ² using a 1 kW ultra-high pressure mercury lamp. Next, development was performed at 30 ° C. for 120 seconds using a 1% aqueous sodium carbonate solution, and the photocurability was visually evaluated according to the following criteria based on the remaining degree of the coating film. In addition, what was x (developability defect) by the said developability evaluation was not evaluated.
○: No effect on coating film (good photocurability)
X: There exists peeling in a coating film (photocurability defect).

[Evaluation of boiling resistance]
A dry coating film was formed in the same manner as the tack-free evaluation, and the coating film was cured by irradiating a light amount of 500 mJ / cm ² using a 1 kW ultra-high pressure mercury lamp. Next, after heating at 150 ° C. for 30 minutes as a high-temperature condition, it was further immersed in boiling ion exchange water for 1 minute. The state of the coating film after immersion was visually evaluated according to the following criteria.
○: No abnormality in the appearance of the coating film ×: Swelling and peeling occurred in part of the coating film.

[Flexibility]
Each resin composition was applied to a polyethylene terephthalate film so that the film thickness after drying was 100 μm, and then dried at 80 ° C. for 30 minutes to obtain a coating film. Next, after performing exposure at ² J / cm ² using an ultraviolet exposure device, it was further heated at 160 ° C. for 1 hour. After cooling to room temperature, the cured coating film was peeled from the polyethylene terephthalate film to obtain a test piece. Using this test piece, at room temperature (23 ° C.) below, with the mandrel of 10 mm [phi, performs bending resistance evaluated according to 8.1 of JIS K 5400 ^-1990, it was visually evaluated for the presence or absence of occurrence of cracks on the following criteria .
○: No crack occurrence ×: Crack occurrence

As described above, the photosensitive resin composition of the present invention has tack-free properties and is excellent in developability and photocurability. Further, it was confirmed that the cured coating film showed excellent water resistance and flex resistance. Therefore, the photosensitive resin composition of the present invention is an alkali-developable photosensitive resin composition for image formation, such as, for example, an etching resist, an electroless plating resist, a build-up printed wiring board insulating layer, a printing plate making, a liquid crystal It can be suitably used for various applications such as for producing display panels.

Claims (5)

A photosensitive resin obtained by reacting a polybasic acid anhydride with a curable resin obtained by reacting an epoxy resin, a phenolic compound having an alcoholic hydroxyl group, and an unsaturated monobasic acid, the epoxy resin A photosensitive resin characterized in that a bifunctional epoxy resin is used and at least a part of the polybasic acid anhydride has a plurality of acid anhydride groups in one molecule. The photosensitive resin according to claim 1, wherein an acid value of the photosensitive resin is 20 to 70 mg KOH / g. The photosensitive resin according to claim 1 or 2, wherein the polybasic acid anhydride having a plurality of acid anhydride units in one molecule is a tetrabasic acid dianhydride. A photosensitive resin composition comprising the photosensitive resin according to claim 1 and a photopolymerization initiator. A cured product obtained by curing the photosensitive resin resin composition according to claim 4.