Curable resin, curable resin intermediate, curable resin, curable resin composition, and method for producing cured product

Abstract

The present invention addresses the problem of providing a curable resin capable of providing a cured product having excellent adhesion and thermal shock resistance, a method for producing an intermediate capable of synthesizing the curable resin, and a method for producing the curable resin. A method for producing a curable resin intermediate, which comprises a step for reacting an epoxy resin having a polydispersity coefficient (Mw / Mn) of 2.8 or more with an unsaturated monoacid in the presence of a benzene or naphthalene to which two or more hydroxyl groups are directly bonded.

Description

Technical Field

[0001] The present invention relates to a curable resin that can be used for image formation and the like, a method for producing an intermediate capable of synthesizing the curable resin, a method for producing the curable resin, and a method for producing a curable resin composition containing the curable resin and a cured product thereof. Background Art

[0002] Epoxy acrylates obtained by modifying epoxy resins with unsaturated monobasic acids can be cured by heat or light, and the cured products have excellent chemical resistance and other properties. Therefore, they are used as curable resins for various molding materials and coatings. Epoxy acrylates are also widely used as photocurable resins for microfabrication and image formation. In this field, it is required to consider the application of the principles of photography from the perspective of image miniaturization, and to be able to develop with dilute weak alkaline aqueous solutions in terms of environmental measures. From this point of view, carboxyl-containing epoxy acrylates obtained by reacting polyacid anhydrides with epoxy acrylates to introduce carboxyl groups are used (for example, Patent Documents 1 to 4, etc.).

[0003] In pattern formation using photocurable resin, the following series of processes are used: after applying curable resin on a substrate, heating and drying to form a coating film, a pattern forming film is pressed against the coating film, and exposure and development are performed. In these series of processes, good developability and high resolution are required for forming fine patterns; or various studies have been conducted on the tack-free property of the curable resin related to the peelability of the pattern forming film after exposure / development. In addition, in recent years, high durability is also required for the cured product after curing the curable resin, and heat resistance and environmental resistance are required to withstand high temperature processing processes (for example, welding on solder resist, ITO film formation on color filter substrate, etc.), heat shock resistance and adhesion.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 61-243869

[0007] Patent Document 2: Japanese Patent Application Laid-Open No. 63-258975

[0008] Patent Document 3: Japanese Patent Application Laid-Open No. 11-222514

[0009] Patent Document 4: Japanese Patent Application Publication No. 2000-109541 Summary of the invention

[0010] Problem that the invention aims to solve

[0011] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a curable resin capable of providing a cured product having excellent adhesion and heat shock resistance, a method for producing an intermediate capable of synthesizing the curable resin, and a method for producing the curable resin.

[0012] Technical Solution

[0013] The present inventors conducted intensive research to solve the above-mentioned technical problems and found that if a curable resin intermediate is manufactured by the following method, the method comprising: reacting an epoxy resin having a polydispersity coefficient (Mw / Mn) of 2.8 or more with an unsaturated monobasic acid in the presence of benzene or naphthalene directly bonded with two or more hydroxyl groups, then the cured product obtained from the curable resin synthesized by the curable resin intermediate is a cured product having excellent adhesion and thermal cycle test resistance (TCT resistance), i.e., heat shock resistance, thereby completing the present invention.

[0014] That is, the present invention is defined by the following constituent requirements.

[0015] [1] A method for producing a curable resin intermediate, comprising: reacting an epoxy resin having a polydispersity coefficient (Mw / Mn) of 2.8 or more with an unsaturated monobasic acid in the presence of benzene or naphthalene to which two or more hydroxyl groups are directly bonded.

[0016] [2] The production method according to [1], wherein the epoxy resin is a cresol novolac type epoxy resin.

[0017] [3] The production method according to [1] or [2], wherein the epoxy resin has a weight average molecular weight of 3,000 or more, a softening point of 85 to 110° C., and an epoxy equivalent of 150 to 300 g / equivalent.

[0018] [4] The production method according to any one of [1] to [3], wherein in the step of reacting the epoxy resin with an unsaturated monobasic acid, the epoxy resin is also reacted with a phenolic compound having an alcoholic hydroxyl group.

[0019] [5] A method for producing a curable resin, comprising: producing a curable resin intermediate by the method according to any one of [1] to [4], and then reacting the obtained curable resin intermediate with a polybasic acid anhydride.

[0020] [6] The production method according to [5], wherein the double bond equivalent of the curable resin is 300 to 620 g / equivalent.

[0021] [7] The production method according to [5] or [6], wherein the acid value of the curable resin is 50 to 100 mgKOH / g.

[0022] [8] A method for producing a curable resin composition, comprising: producing a curable resin by the production method according to any one of [5] to [7], and then mixing the obtained curable resin, a polymerization initiator, and a monomer added as needed.

[0023] [9] A method for producing a cured product, comprising producing a curable resin composition by the production method according to [8], and then curing the obtained curable resin composition.

[0024]

[10] A curable resin, wherein the curable resin comprises: an epoxy resin-derived portion having a structure in which an epoxy group of an epoxy resin is ring-opened; an unsaturated monobasic acid residue bonded to a carbon atom of the ring-opened portion of the epoxy group; and a polybasic acid anhydride residue bonded to an oxygen atom of the ring-opened portion of the epoxy group, the polydispersity coefficient (Mw / Mn) of the epoxy resin-derived portion being 2.8 or more, and the curable resin contains benzene or naphthalene directly bonded with two or more hydroxyl groups.

[0025] Beneficial Effects

[0026] The curable resin intermediate of the present invention is manufactured by reacting an epoxy resin with an unsaturated monobasic acid in the presence of benzene or naphthalene directly bonded with two or more hydroxyl groups, and using an epoxy resin having a polydispersity coefficient (Mw / Mn) of 2.8 or more as the epoxy resin. Therefore, the curable resin intermediate of the present invention and the curable resin synthesized by the intermediate can provide a cured product having excellent adhesion, and not easily cracked even when repeatedly subjected to a high temperature and low temperature thermal history, that is, excellent thermal shock resistance. DETAILED DESCRIPTION

[0027] 1. Curable resin intermediate

[0028] In the present invention, the curable resin intermediate is obtained by the following manufacturing method, the manufacturing method comprising: a step of reacting an epoxy resin having a polydispersity coefficient (Mw / Mn) of 2.8 or more with an unsaturated monobasic acid in the presence of benzene or naphthalene directly bonded with two or more hydroxyl groups. According to the manufacturing method of the curable resin intermediate of the present invention, by reacting an unsaturated monobasic acid with an epoxy resin, a free radical polymerizable double bond can be introduced into the structure. If the curable resin intermediate is used, a curable resin that can form a cured product with excellent adhesion and TCT resistance can be provided. In addition, the cured product is preferably excellent in developability and detackification. It should be noted that the curable resin intermediate can also be used as a curable resin (for example, as epoxy (meth) acrylate, etc.) without reacting the curable resin intermediate with a polyacid anhydride, but it is preferred that the curable resin intermediate is reacted with a polyacid anhydride to be used as a curable resin (for example, as carboxyl-containing epoxy (meth) acrylate, etc.).

[0029] In the production of the curable resin intermediate, an epoxy resin having a polydispersity coefficient (Mw / Mn) of 2.8 or more is used. The epoxy resin is not particularly limited as long as it is a compound having two or more epoxy groups in one molecule and a polydispersity coefficient (Mw / Mn) of 2.8 or more, and a known epoxy resin can be used.

[0030] The polydispersity coefficient (Mw / Mn) of the epoxy resin can be determined by gel permeation chromatography (GPC).

[0031] Examples of epoxy resins include: bisphenol-type epoxy resins such as bisphenol A epoxy resin and bisphenol F epoxy resin; novolac-type epoxy resins such as phenol novolac-type epoxy resins, cresol novolac-type epoxy resins, and naphthalene-containing novolac-type epoxy resins; trisphenol methane-type epoxy resins; dicyclopentadiene-type epoxy resins; biphenyl-type epoxy resins; alicyclic epoxy resins; glycidylamine-type epoxy resins; glycidyl ester-type epoxy resins; a reaction product of a polyphenol compound obtained by a condensation reaction of a phenolic compound such as phenol, o-cresol, m-cresol, and naphthol with an aromatic aldehyde having a phenolic hydroxyl group and epichlorohydrin; a reaction product of a polyphenol compound obtained by an addition reaction of a phenolic compound with a diene compound such as divinylbenzene and dicyclopentadiene and epichlorohydrin; and the like. Furthermore, those obtained by bonding and chain-extending two or more molecules of these epoxy resins by reaction with a chain extender such as a polybasic acid, a polyphenol compound, a polyfunctional amino compound or a polythiol may also be used.

[0032] As the epoxy resin, preferably a novolac epoxy resin or a trisphenol methane epoxy resin is used, and a novolac epoxy resin is more preferably used. As the novolac epoxy resin, preferably a phenol novolac epoxy resin and a cresol novolac epoxy resin, more preferably a cresol novolac epoxy resin. As the cresol novolac epoxy resin, it can be any of an o-cresol novolac epoxy resin (hereinafter also referred to as an o-cresol novolac epoxy resin), a m-cresol novolac epoxy resin, and a p-cresol novolac epoxy resin, preferably an o-cresol novolac epoxy resin. In the case of using a cresol novolac epoxy resin, the cresol novolac epoxy resin can be used as at least a part of the epoxy resin. By using a cresol novolac epoxy resin, the heat resistance of the cured product formed by the curable resin obtained by the curable resin intermediate can be improved. As the cresol novolac type epoxy resin, a known one can be used, and for example, it can be produced by the reaction of cresol and epichlorohydrin.

[0033] In the present invention, it is preferred that a cresol novolac epoxy resin having a polydispersity index (Mw / Mn) of 2.8 or more is used as the main component of the epoxy resin. It should be noted that being used as the main component of the epoxy resin means using more than 50% by mass in 100% by mass of all epoxy resins. The usage amount of the cresol novolac epoxy resin having a polydispersity index (Mw / Mn) of 2.8 or more is preferably 80% by mass or more in 100% by mass of all epoxy resins, more preferably 90% by mass or more, and further preferably 95% by mass or more, and it is particularly preferred that substantially only a cresol novolac epoxy resin having a polydispersity index (Mw / Mn) of 2.8 or more is used as the epoxy resin.

[0034] As the cresol novolac epoxy resin having a polydispersity coefficient (Mw / Mn) of 2.8 or more, specifically, cresol novolac epoxy resin YDCN-704A manufactured by NIPPON STEEL Chemical & Material Co., Ltd., etc. can be used.

[0035] The curable resin intermediate is manufactured by using an epoxy resin having a polydispersity coefficient (Mw / Mn) of 2.8 or more. The cured product obtained from the curable resin synthesized by the curable resin intermediate has excellent developability and adhesion, is not prone to cracking even when a thermal history of high and low temperatures is repeatedly applied, and has excellent TCT resistance, i.e., heat shock resistance.

[0036] The polydispersity index (Mw / Mn) of the epoxy resin is preferably 2.83 or more, and more preferably 2.85 or more. On the other hand, the upper limit of the polydispersity index (Mw / Mn) of the epoxy resin is not particularly limited, but is preferably 3.5 or less from the perspective of operability. That is, the polydispersity index (Mw / Mn) of the epoxy resin is preferably 2.83 to 3.5, and more preferably 2.85 to 3.5. It should be noted that, in the case of using a cresol novolac type epoxy resin as the epoxy resin, the polydispersity index (Mw / Mn) is further preferably 3.3 or less, further preferably 3.25 or less, and even more preferably 3.2 or less. That is, the polydispersity index (Mw / Mn) in the case of using a cresol novolac type epoxy resin as the epoxy resin is preferably 2.83 to 3.5, more preferably 2.85 to 3.5, further preferably 2.85 to 3.3, further preferably 2.85 to 3.25, and even more preferably 2.85 to 3.2. By using a cresol novolac-type epoxy resin having a polydispersity coefficient (Mw / Mn) of 3.3 or less, a curable resin having excellent detackifying properties and / or developing properties can be easily obtained.

[0037] From the perspective of further improving the thermal shock resistance, the softening point of the epoxy resin is preferably 85°C or more, more preferably 89°C or more. It should be noted that when a cresol novolac epoxy resin is used as the epoxy resin, the softening point is preferably 85°C or more, more preferably 87°C or more, more preferably 89°C or more, more preferably 89.5°C or more, more preferably 90°C or more, and more preferably 90.5°C or more. The higher the softening point, the more excellent the detackification and thermal shock resistance of the cured product can be obtained. On the other hand, the upper limit of the softening point of the epoxy resin is not particularly limited, but from the perspective of operability, it is preferably 110°C or less. It should be noted that when a cresol novolac epoxy resin is used as the epoxy resin, the softening point is more preferably 103°C or less, more preferably 102.5°C or less, and more preferably 102°C or less. That is, the softening point of the epoxy resin is preferably 85-110°C, more preferably 89-110°C. In addition, when a cresol novolac epoxy resin is used as the epoxy resin, the softening point is preferably 85 to 110°C, more preferably 87 to 103°C, further preferably 89 to 102.5°C, further preferably 89.5 to 102°C, further preferably 90 to 102°C, further more preferably 90.5 to 102°C. By using a cresol novolac epoxy resin having a softening point of 103° or less, a curable resin having excellent developability can be easily obtained. In addition, the polydispersity coefficient (Mw / Mn) of the epoxy resin is 2.8 or more, so even if the softening point of the epoxy resin is 96°C or less, the formed cured product can have sufficient heat shock resistance.

[0038] The softening point of the epoxy resin can be determined according to JIS K 7234 (1986).

[0039] The weight average molecular weight (Mw) of the epoxy resin is preferably 3000 or more. It should be noted that, when a cresol novolac type epoxy resin is used as the epoxy resin, the weight average molecular weight (Mw) is more preferably 3100 or more, further preferably 3300 or more, and further preferably 3650 or more. On the other hand, the upper limit of the weight average molecular weight (Mw) of the epoxy resin is not particularly limited, but is preferably 15000 or less from the perspective of operability. It should be noted that, when a cresol novolac type epoxy resin is used as the epoxy resin, the weight average molecular weight (Mw) is more preferably 10000 or less, further preferably 8000 or less, and further preferably 6000 or less. That is, the weight average molecular weight (Mw) of the epoxy resin is preferably 3000 to 15000. When a cresol novolac epoxy resin is used as the epoxy resin, the weight average molecular weight (Mw) is preferably 3,000 to 15,000, more preferably 3,100 to 10,000, further preferably 3,300 to 8,000, and further preferably 3,650 to 6,000.

[0040] The weight average molecular weight (Mw) of the epoxy resin can be determined by gel permeation chromatography (GPC).

[0041] The epoxy equivalent of the epoxy resin is preferably 150 to 300 g / equivalent, more preferably 160 to 270 g / equivalent, and further preferably 170 to 250 g / equivalent.

[0042] The epoxy equivalent of the epoxy resin can be determined according to JIS K 7236 (2001).

[0043] As the unsaturated monobasic acid used to prepare the curable resin intermediate, any compound having one acid group and one or more free radical polymerizable unsaturated bonds in one molecule may be used. Examples of the acid group include carboxyl, sulfonic acid, phosphoric acid, etc., preferably carboxyl. By reacting the unsaturated monobasic acid with the epoxy resin, the acid group of the unsaturated monobasic acid can react with the epoxy group of the epoxy resin, thereby introducing a free radical polymerizable double bond into the epoxy resin.

[0044] As unsaturated monobasic acids, for example, acrylic acid, methacrylic acid, crotonic acid, cinnamic acid, β-acryloxy propionic acid, a reaction product of a hydroxyalkyl (meth)acrylate having one hydroxyl group and one (meth)acryloyl group and a dibasic acid anhydride, a reaction product of a multifunctional (meth)acrylate having one hydroxyl group and two or more (meth)acryloyl groups and a dibasic acid anhydride, and caprolactone modified products of these monobasic acids, etc. These unsaturated monobasic acids can be used alone or in combination. Among them, alkenyl carboxylic acids are preferably used, and acrylic acid or methacrylic acid is more preferred.

[0045] In the process of reacting an epoxy resin with an unsaturated monobasic acid in the presence of benzene or naphthalene directly bonded with two or more hydroxyl groups, the epoxy resin can also be further reacted with a phenolic compound having an alcoholic hydroxyl group (hereinafter also referred to as "phenolic compound A"). By reacting the phenolic compound having an alcoholic hydroxyl group, an alcoholic hydroxyl group can be introduced into the curable resin intermediate with the aid of a phenoxy unit. In the manufacturing process of the curable resin described later, the introduced alcoholic hydroxyl group has less steric hindrance than the hydroxyl group generated by the ring opening of the epoxy group possessed by the epoxy resin, and therefore reacts preferentially with a polyacid anhydride. According to the curable resin synthesized by the following curable resin intermediate, a cured product with further improved adhesion and TCT resistance can be obtained, wherein the curable resin intermediate is obtained by reacting the epoxy resin not only with an unsaturated monobasic acid but also with the phenolic compound A.

[0046] The phenolic compound with alcoholic hydroxyl group refers to an aromatic ring compound with alcoholic hydroxyl group and phenolic hydroxyl group. Phenolic hydroxyl group refers to a hydroxyl group directly bonded to the aromatic ring. In addition to the benzene ring, the aromatic ring is preferably an aromatic hydrocarbon ring such as a naphthalene ring, and can also be an aromatic heterocycle. The hydroxyl group directly bonded to the aromatic ring shows the same strong acidity as phenol and is classified as a phenolic hydroxyl group. On the other hand, the alcoholic hydroxyl group is indirectly bonded to the aromatic ring. The reactivity of these two hydroxyl groups with the epoxy group of the epoxy resin is different. The phenolic hydroxyl group preferentially reacts with the epoxy group, and the alcoholic hydroxyl group remains in an unreacted state. Therefore, when mixed with a polyacid anhydride next, the remaining alcoholic hydroxyl group reacts with the polyacid anhydride. The phenolic compound with alcoholic hydroxyl group can also have multiple alcoholic hydroxyl groups and / or multiple phenolic hydroxyl groups, and can also have other substituents (for example, alkyl, alkoxy, aryl, aryloxy, acyl, alkoxycarbonyl, aryloxycarbonyl, etc.).

[0047] As described above, the alcoholic hydroxyl group is indirectly bonded to the aromatic ring. Examples of the group present between the aromatic ring and the alcoholic hydroxyl group include: an alkylene group having 1 to 10 carbon atoms, such as a methylene group and an ethylene group; a group composed of a -C(=O)O- group and one or two alkylene groups having 1 to 10 carbon atoms; a group composed of an -O- group and one or two alkylene groups having 1 to 10 carbon atoms; a group composed of a divalent aromatic ring, such as a phenylene group, an -O- group and an alkylene group, etc. In any of the examples, it is preferred that the alcoholic hydroxyl group is bonded to the alkylene group.

[0048] As phenolic compounds having an alcoholic hydroxyl group, for example, there can be listed: hydroxyalkylphenols such as p-hydroxyphenyl-2-ethanol, p-hydroxyphenyl-3-propanol, p-hydroxyphenyl-4-butanol, (bis)hydroxymethylphenol, hydroxymethyl-di-tert-butylphenol; hydroxyalkylcresols such as (bis)hydroxymethylcresol and hydroxyethylcresol; esters of carboxyl-containing phenolic compounds such as hydroxybenzoic acid, hydroxyphenylbenzoic acid, hydroxyphenoxybenzoic acid, and ethylene glycol, propylene glycol, glycerol, etc.; monoethylene oxide adducts of bisphenol; monopropylene oxide adducts of bisphenol, etc. These phenolic compounds A can be used alone or in combination. Among them, hydroxyalkylphenol or hydroxyalkylcresol is preferably used, and hydroxyalkylphenol is more preferably used.

[0049] In the case of manufacturing a curable resin intermediate without using a phenolic compound having an alcoholic hydroxyl group, the unsaturated monobasic acid is reacted in a manner such that the acid group in the unsaturated monobasic acid is preferably 0.6 to 1.4 moles, more preferably 0.7 to 1.3 moles, and further preferably 0.8 to 1.1 moles relative to 1 chemical equivalent (molar equivalent) of the epoxy group in the epoxy resin. By reacting at such a ratio, it is easy to make the curability of the curable resin obtained by the curable resin intermediate good, and the storage stability of the curable resin is improved.

[0050] When a phenolic compound having an alcoholic hydroxyl group is used to manufacture a curable resin intermediate, there are the following methods, etc.: a method in which an epoxy resin is reacted with an unsaturated monobasic acid and then the phenolic compound having an alcoholic hydroxyl group is reacted; a method in which an epoxy resin is reacted with an unsaturated monobasic acid and a phenolic compound having an alcoholic hydroxyl group at one time; and a method in which an epoxy resin is reacted with a phenolic compound having an alcoholic hydroxyl group and then the unsaturated monobasic acid is reacted. Any method may be used.

[0051] In the case of using a phenolic compound having an alcoholic hydroxyl group to manufacture a curable resin intermediate, the unsaturated monoacid preferably reacts 0.5 to 0.85 moles relative to 1 chemical equivalent (molar equivalent) of the epoxy group in the epoxy resin, more preferably 0.55 to 0.8 moles, and further preferably 0.6 to 0.75 moles. By reacting more than 0.5 moles of the unsaturated monoacid relative to 1 chemical equivalent of the epoxy group in the epoxy resin, it is easy to make the curability of the obtained curable resin good. By reacting less than 0.85 moles of the unsaturated monoacid relative to 1 chemical equivalent of the epoxy group in the epoxy resin, the brittleness of the obtained cured product can be reduced, and the TCT resistance can be further improved.

[0052] When a phenolic compound having an alcoholic hydroxyl group is used to manufacture a curable resin intermediate, the phenolic compound having an alcoholic hydroxyl group is preferably reacted in an amount of 0.15 to 0.5 moles relative to one chemical equivalent (molar equivalent) of epoxy groups in the epoxy resin, more preferably 0.2 to 0.45 moles, and further preferably 0.25 to 0.4 moles. By reacting 0.15 moles or more of the phenolic compound A relative to one chemical equivalent of epoxy groups in the epoxy resin, the flexibility of the resulting cured product can be improved. By reacting 0.5 moles or less of the phenolic compound A relative to one chemical equivalent of epoxy groups in the epoxy resin, the curability of the resulting curable resin can be easily improved.

[0053] As the total amount of the unsaturated monobasic acid and the phenolic compound A, it is preferably set to 0.8 to 1.1 moles relative to 1 chemical equivalent (molar equivalent) of the epoxy group in the epoxy resin, and more preferably set to 0.85 to 1.05 moles. If the total amount of the unsaturated monobasic acid and the phenolic compound A is 0.8 moles or more relative to 1 chemical equivalent of the epoxy group in the epoxy resin, it is easy to fully exert the effect of introducing the unsaturated monobasic acid and the phenolic compound A into the epoxy resin. On the other hand, if the total amount of the unsaturated monobasic acid and the phenolic compound A is 1.1 moles or less relative to 1 chemical equivalent of the epoxy group in the epoxy resin, the amount of the unsaturated monobasic acid and the phenolic compound A that remain unreacted is reduced. If the amount of the unsaturated monobasic acid and the phenolic compound A that remain unreacted is reduced, the storage stability of the obtained curable resin is improved, and the reduction in the characteristics of the obtained cured product can be suppressed.

[0054] In the manufacture of curable resin intermediate, the reaction of epoxy resin and unsaturated monoacid is carried out in the presence of benzene or naphthalene directly bonded with two or more hydroxyl groups. Therefore, the obtained curable resin intermediate contains benzene or naphthalene directly bonded with two or more hydroxyl groups. In the reaction, benzene or naphthalene directly bonded with two or more hydroxyl groups plays a role as a polymerization inhibitor. In addition, in the curable resin composition containing the curable resin manufactured by the curable resin intermediate, there is benzene or naphthalene directly bonded with two or more hydroxyl groups, so the brittleness of the obtained cured product is reduced, and the TCT tolerance is further improved. It can be considered that the effect is obtained by interacting with the curable resin skeleton respectively by at least two phenolic hydroxyl groups possessed by the benzene or naphthalene, thereby acting as a buffer material between the curable resin skeletons.

[0055] Benzene or naphthalene directly bonded with two or more hydroxyl groups does not have a substituent other than the phenolic hydroxyl group, and therefore advantageously functions as a buffer material between curable resin skeletons. In contrast, in the case of benzene or naphthalene having a substituent other than the phenolic hydroxyl group, the effect as a buffer material between curable resin skeletons is poor. For example, when methyl hydroquinone is used in the manufacture of a curable resin intermediate, due to the steric hindrance of the methyl group of methyl hydroquinone, any of the two phenolic hydroxyl groups becomes difficult to interact with the curable resin skeleton, and the effect as a buffer material between curable resin skeletons is poor.

[0056] As benzene or naphthalene having two or more hydroxyl groups directly bonded thereto, for example, hydroquinone, catechol, 1,2,3-trihydroxybenzene, 1,2,4-trihydroxybenzene, 1,2-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 1,3,8-trihydroxynaphthalene, etc. These benzenes or naphthalenes can be used alone or in combination. As benzene or naphthalene having two or more hydroxyl groups directly bonded thereto, quinone reduction products such as hydroquinone, catechol, 1,2-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, and 2,6-dihydroxynaphthalene are preferred, and quinone reduction products in which two hydroxyl groups are not adjacent, i.e., hydroquinone, 1,4-dihydroxynaphthalene, and 2,6-dihydroxynaphthalene, etc. are more preferred, and hydroquinone is particularly preferred.

[0057] The amount of benzene and / or naphthalene having two or more hydroxyl groups directly bonded thereto is preferably 0.001 to 1% by mass, more preferably 0.005 to 0.9% by mass, further preferably 0.01 to 0.7% by mass, and still further preferably 0.05 to 0.5% by mass, based on 100% by mass of the epoxy resin.

[0058] In the manufacture of the curable resin intermediate, in addition to using benzene or naphthalene directly bonded with two or more hydroxyl groups, other polymerization inhibitors can also be used. As other polymerization inhibitors, there are no particular limitations, and known polymerization inhibitors can be used. As other polymerization inhibitors, for example, methyl hydroquinone, benzoquinone, hydroquinone monomethyl ether, p-tert-butyl hydroquinone, 2,6-di-tert-butyl-4-methylphenol, 6-tert-butyl-2,4-dimethylphenol, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), p-tert-butylcatechol, N,N-diethylhydroxylamine, 1,1-diphenyl-2-picrylhydrazyl, tri-p-nitrophenylmethyl, phenothiazine, 2,2,6,6-tetramethylpiperidinyl 1-oxyl, oxygen, etc. can be used.

[0059] The amount of other polymerization inhibitors used is preferably 10% by mass or less, more preferably 5% by mass or less, further preferably 1% by mass or less, and particularly preferably 0% by mass, based on 100% by mass of the total amount of the polymerization inhibitors including benzene and naphthalene directly bonded with two or more hydroxyl groups.

[0060] As described above, the curable resin intermediate can be obtained by the following manufacturing method, which comprises: a step of reacting an epoxy resin having a polydispersity coefficient (Mw / Mn) of 2.8 or more with an unsaturated monobasic acid in the presence of benzene or naphthalene directly bonded with two or more hydroxyl groups. In addition, the epoxy resin can also be further reacted with a phenolic compound having an alcoholic hydroxyl group. When the phenolic compound having an alcoholic hydroxyl group is also reacted, the reaction of the epoxy resin with the unsaturated monobasic acid and the reaction of the epoxy resin with the phenolic compound having an alcoholic hydroxyl group can be carried out either first or simultaneously.

[0061] The reaction of the epoxy resin, the unsaturated monobasic acid and the phenolic compound having an alcoholic hydroxyl group added as required is preferably carried out at 80° C. to 130° C., more preferably at 90° C. to 120° C., in the presence of a reaction catalyst. In addition, the reaction may be carried out in the presence of a radical polymerizable compound described later, a diluent such as a solvent, etc., as required.

[0062] As reaction catalysts, tertiary amines such as triethylamine, quaternary ammonium salts such as triethylbenzylammonium chloride, imidazole compounds such as 2-ethyl-4-methylimidazole, phosphorus compounds such as triphenylphosphine, organic acid salts or inorganic acid salts of metals (lithium chloride, etc.) or chelate compounds, etc., can be listed. The amount of the reaction catalyst used is not particularly limited, for example, preferably in the range of 0.0001 to 5.0% by mass, more preferably 0.001 to 1.0% by mass, relative to the total mass of the reaction raw materials.

[0063] In the curable resin intermediate obtained by the production method of the present invention, there are hydroxyl groups generated by the reaction of unsaturated monobasic acid with epoxy groups in epoxy resins and the ring opening of such epoxy groups. In addition, when a phenolic compound having an alcoholic hydroxyl group is reacted, in addition to the hydroxyl groups, there are hydroxyl groups derived from the phenolic compound A and hydroxyl groups generated by the reaction of the phenolic compound A with epoxy groups in epoxy resins and the ring opening of such epoxy groups.

[0064] 2. Curable resin

[0065] The curable resin of the present invention is a free radical polymerizable curable resin obtained by modifying an epoxy resin. The curable resin of the present invention is specifically obtained by reacting a polyacid anhydride with a curable resin intermediate which is a reaction product of an epoxy resin and an unsaturated monobasic acid, and more specifically obtained by the following manufacturing method, the manufacturing method comprising: a step of introducing a carboxyl group by reacting a polyacid anhydride with a hydroxyl group possessed by the curable resin intermediate. The curable resin obtained by the manufacturing method of the present invention is a resin in which free radical polymerizable double bonds and carboxyl groups are introduced into an epoxy resin, and therefore has alkali developability and curability using heat and light, and can be used as an alkali developable curable resin for image formation, etc. In addition, if the curable resin of the present invention is used, a cured product with excellent adhesion and TCT resistance can be formed.

[0066] Polybasic acid anhydride refers to a compound formed by acid anhydriding multiple acid groups with acid groups, and the number of acid anhydride groups can be more than one. As polybasic acid anhydride, for example, phthalic anhydride, succinic anhydride, octenyl succinic anhydride, penta (dodecenyl) succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, 3,6-endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, tetrabromophthalic anhydride, trimellitic acid and other dibasic acid anhydrides; biphenyltetracarboxylic dianhydride, diphenyl ether tetracarboxylic dianhydride, butane tetracarboxylic dianhydride, cyclopentane tetracarboxylic dianhydride, pyromellitic anhydride, benzophenone tetracarboxylic dianhydride and other aliphatic or aromatic tetracarboxylic dianhydrides, etc. These polybasic acid anhydrides can be used one or more. Among them, dibasic acid anhydrides are preferred, dibasic acid anhydrides having an ethylenically unsaturated double bond are more preferred, and tetrahydrophthalic anhydride and maleic anhydride are still more preferred.

[0067] The polyanhydride is reacted in such a manner that the acid anhydride group in the polyanhydride is preferably 0.1 to 1.1 moles, more preferably 0.2 to 0.9 moles, relative to 1 chemical equivalent (molar equivalent) of the hydroxyl group in the curable resin intermediate. By reacting the polyanhydride in this way, a carboxyl group can be appropriately introduced into the obtained curable resin, and the reaction between the polyanhydride and the curable resin intermediate can be efficiently carried out.

[0068] As described above, the curable resin can be obtained by a production method including a step of reacting a curable resin intermediate with a polybasic acid anhydride.

[0069] The reaction of the curable resin intermediate and the polyacid anhydride is preferably carried out at 50°C to 130°C, and more preferably at 70°C to 110°C, in the presence of benzene or naphthalene directly bonded with two or more hydroxyl groups. In addition, the reaction may also be carried out in the presence of a reaction catalyst and / or a diluent such as a free radical polymerizable compound or a solvent as described later, as required. It should be noted that the reaction of the curable resin intermediate and the polyacid anhydride is conveniently carried out in the following manner: the polyacid anhydride is added to the reaction solution after the reaction of the curable resin intermediate is produced.

[0070] As for the benzene or naphthalene directly bonded with two or more hydroxyl groups, when the reaction of the curable resin intermediate is followed by the reaction of the curable resin intermediate with a polyacid anhydride, the benzene and / or naphthalene directly bonded with two or more hydroxyl groups in the reaction solution used in the manufacture of the curable resin intermediate can be continued to be used, or the benzene and / or naphthalene directly bonded with two or more hydroxyl groups can be further added. From the perspective of simplicity, it is preferred to continue to use the benzene and / or naphthalene directly bonded with two or more hydroxyl groups used in the manufacture of the curable resin intermediate. The amount of benzene and / or naphthalene directly bonded with two or more hydroxyl groups in the reaction of the curable resin intermediate with a polyacid anhydride is preferably 0.001 to 1% by mass relative to 100% by mass of the epoxy resin constituting the curable resin intermediate. It is more preferably 0.005 to 0.9% by mass, more preferably 0.01 to 0.7% by mass, and even more preferably 0.05 to 0.5% by mass.

[0071] As the reaction catalyst, tertiary amines such as triethylamine, quaternary ammonium salts such as triethylbenzylammonium chloride, metal salts such as lithium chloride, etc. can be cited. As for the reaction catalyst, when the reaction of the curable resin intermediate is followed by the reaction of the curable resin intermediate with the polyacid anhydride, the reaction catalyst in the reaction solution used when the curable resin intermediate is manufactured can be continued to be used, or a reaction catalyst can be further added. From the perspective of simplicity, it is preferred to continue to use the reaction catalyst used when the curable resin intermediate is manufactured. The amount of the reaction catalyst used in the reaction of the curable resin intermediate with the polyacid anhydride is not particularly limited. For example, it is preferably in the range of 0.0001 to 5.0% by mass, and more preferably 0.001 to 1.0% by mass, relative to the total mass of the reaction raw materials.

[0072] The reaction product obtained by reacting the curable resin intermediate with the polyacid anhydride is preferably filtered. That is, in the present invention, it is preferred that after the curable resin intermediate is reacted with the polyacid anhydride to obtain a crude product, a step of filtering the crude product (filtration step) is performed. By filtering, insoluble matter (inclusions) contained in the crude product can be removed, and the curable resin obtained in this way can achieve good pattern accuracy when used in image formation.

[0073] The filtration can be carried out using known filter materials such as bag filters, cartridge filters, stainless steel metal meshes, etc., and preferably uses filter materials that are resistant to the use of solvents and acids. The filtration can be carried out under normal pressure, or the primary side (inlet side) of the filter material can be pressurized, or the secondary side (outlet side) of the filter material can be depressurized, and a known filtration method can be used. From the perspective of improving the filtration accuracy, the pore size (mesh) of the filter material is preferably 100 μm or less, more preferably 50 μm or less, and from the perspective of ensuring the filtration speed (productivity), the pore size (mesh) of the filter material is preferably 0.1 μm or more, more preferably 1 μm or more. That is, the pore size of the filter material is preferably 0.1 to 100 μm, more preferably 1 to 50 μm. From the perspective of the working environment, safety and productivity, the filtration temperature is preferably 20°C or more, more preferably 30°C or more, and preferably 100°C or less, more preferably 95°C or less. That is, the filtration temperature is preferably 20 to 100°C, more preferably 30 to 95°C.

[0074] According to the method for producing a curable resin of the present invention, a curable resin intermediate is reacted with a polybasic acid anhydride, and the polybasic acid anhydride reacts with a hydroxyl group possessed by the curable resin intermediate, thereby introducing a carboxyl group. The curable resin containing a carboxyl group can be developed with an alkali, so the curable resin of the present invention can be used as an alkali-developable curable resin for image formation, etc. In particular, in the case of using a curable resin intermediate obtained by a manufacturing method including a step of reacting a phenolic compound having an alcoholic hydroxyl group, the polybasic acid anhydride preferentially reacts with a hydroxyl group derived from the phenolic compound A, so that the double bond portion introduced by the reaction with the unsaturated monobasic and the carboxyl group introduced by the reaction with the polybasic acid anhydride exist in a fully separated manner, and the functions of each functional group are more effectively exerted.

[0075] The curable resin of the present invention has: an epoxy resin-derived portion having a structure formed by ring-opening an epoxy group of an epoxy resin; an unsaturated monobasic acid residue bonded to a carbon atom of the ring-opening portion of the epoxy group; and a polyacid anhydride residue bonded to an oxygen atom of the ring-opening portion of the epoxy group. The curable resin of the present invention introduces a free radical polymerizable double bond and a carboxyl group into the epoxy resin, so it has alkali developability and curability using heat and light. Moreover, the polydispersity coefficient (Mw / Mn) of the epoxy resin-derived portion is 2.8 or more, so it can form a cured product with excellent adhesion, which is not easy to crack even if a high temperature and low temperature thermal history is repeatedly applied, and has excellent TCT resistance, that is, heat shock resistance. In addition, the following curable resin can form a cured product with better free radical polymerizability, alkali developability, and further improved adhesion and TCT resistance, wherein the curable resin has a phenolic compound residue with an alcoholic hydroxyl group bonded to a carbon atom of the ring-opening portion of the epoxy group and has a structure in which a polyacid anhydride residue is bonded to an oxygen atom possessed by the phenolic compound A.

[0076] The acid value of the curable resin is preferably 30 to 120 mgKOH / g, more preferably 40 to 110 mgKOH / g, and further preferably 50 to 100 mgKOH / g. If the acid value of the curable resin is 30 mgKOH / g or more, good alkali developability is easily exhibited even in a weakly alkaline aqueous solution. If the acid value of the curable resin is 120 mgKOH / g or less, the exposed portion is not easily corroded by the alkaline developer, and the water resistance and moisture resistance of the obtained cured product are improved.

[0077] The double bond equivalent of the curable resin (molecular weight per chemical equivalent of free radical polymerizable double bonds) is preferably 300 to 620 g / equivalent, more preferably 330 to 610 g / equivalent, and further preferably 350 to 600 g / equivalent. By controlling the polydispersity coefficient (Mw / Mn) of the epoxy resin and the double bond equivalent of the curable resin at the same time, the range of physical properties of the obtained cured product is expanded. If the double bond equivalent of the curable resin is 300 g / equivalent or more, the curability of the curable resin is improved, and the thermal properties of the obtained cured product are good. If the double bond equivalent of the curable resin is 620 g / equivalent or less, the flexibility of the obtained cured product is improved.

[0078] The double bond equivalent of the curable resin is determined by dividing the total mass of the curable resin by the number of moles of radical polymerizable double bonds introduced into the curable resin.

[0079] The curable resin preferably contains benzene or naphthalene directly bonded with two or more hydroxyl groups. The content of benzene and / or naphthalene directly bonded with two or more hydroxyl groups in the curable resin is preferably 0.0005 to 0.8% by mass, more preferably 0.002 to 0.7% by mass, further preferably 0.005 to 0.6% by mass, and further preferably 0.02 to 0.4% by mass in 100% by mass of the curable resin.

[0080] 3. Curable resin composition

[0081] The curable resin composition of the present invention is a composition containing the curable resin and polymerization initiator described above, and may also contain monomers (particularly free radical polymerizable monomers). The curable resin composition can be obtained by the following manufacturing method, which comprises: a process of obtaining a curable resin by the manufacturing method of the curable resin of the present invention; and a process (combining process) of mixing a curable resin and a polymerization initiator. The curable resin composition can be cured by applying heat or light irradiation to the curable resin to form a cured product. If the curable resin composition of the present invention is used, a cured product with excellent adhesion and TCT resistance can be formed.

[0082] The curable resin of the present invention can also be heat-cured by using a known thermal polymerization initiator, but from the perspective of being able to micro-process or image-form the cured product by photolithography, it is preferably photocured by adding a photopolymerization initiator. In this regard, as the polymerization initiator, a photopolymerization initiator is preferably used.

[0083] As the thermal polymerization initiator, known substances can be used, and examples thereof include organic peroxides such as methyl ethyl ketone peroxide, benzoyl peroxide, diisopropylbenzene peroxide, tert-butyl hydroperoxide, cumene hydroperoxide, tert-butyl peroxyoctanoate, tert-butyl peroxybenzoate, lauroyl peroxide, and azo compounds such as azobisisobutyronitrile. The above-mentioned thermal polymerization initiators can be used alone or in combination of two or more. In the thermal polymerization application, a curing accelerator can also be mixed in the resin composition for use. As such a curing accelerator, cobalt naphthenate, cobalt octanoate, or tertiary amines can be listed as representative examples.

[0084] The amount of the thermal polymerization initiator used is preferably 0.05% by mass to 5% by mass based on 100% by mass of the total of the curable resin and the radical polymerizable compound used as required.

[0085] As the photopolymerization initiator, a known photopolymerization initiator can be used, and examples thereof include: benzoin and its alkyl ethers such as benzoin, benzoin methyl ether, and benzoin ethyl ether; acetophenones such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, and 4-(1-tert-butylperoxy-1-methylethyl)acetophenone; anthraquinones such as 2-methylanthraquinone, 2-amylanthraquinone, 2-tert-butylanthraquinone, and 1-chloroanthraquinone; 2,4-dimethylthioxanthone, 2,4-diisopropylthioxanthone, Thioxanthones such as 2-chlorothioxanthone; ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzophenones such as benzophenone, 4-(1-tert-butylperoxy-1-methylethyl)benzophenone, 3,3',4,4'-tetrakis(tert-butylperoxycarbonyl)benzophenone; 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propane-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1; acylphosphine oxides and xanthones, etc. The above-mentioned photopolymerization initiators may be used alone or in combination of two or more.

[0086] The amount of the photopolymerization initiator used is preferably 0.3 to 20% by mass, more preferably 0.5 to 15% by mass, and further preferably 1 to 10% by mass, based on 100% by mass of the total of the curable resin and the radical polymerizable compound used as required.

[0087] The curable resin composition may also contain a free radical polymerizable compound. Therefore, in the compounding step, in addition to the curable resin and the polymerization initiator, a free radical polymerizable compound may also be compounded. The free radical polymerizable compound may be a compound having only one double bond capable of free radical polymerization, or a compound having two or more double bonds capable of free radical polymerization. The free radical polymerizable compound participates in photopolymerization, which can improve the properties of the obtained cured product or adjust the viscosity of the curable resin composition.

[0088] The preferred amount used when using a free radical polymerizable compound is preferably 5% by mass or more, more preferably 10% by mass or more, and is preferably 500% by mass or less, more preferably 100% by mass or less (i.e., preferably 5 to 500% by mass, more preferably 10 to 100% by mass), relative to 100% by mass of the curable resin.

[0089] As free radical polymerizable compounds, free radical polymerizable oligomers and free radical polymerizable monomers can be cited. As free radical polymerizable oligomers, for example, unsaturated polyesters, epoxy acrylates, urethane acrylates, polyester acrylates, etc. can be used. As free radical polymerizable monomers, for example, aromatic vinyl monomers such as styrene, α-methylstyrene, α-chlorostyrene, vinyl toluene, divinylbenzene, diallyl phthalate, diallyl phenylphosphonate, etc.; vinyl ester monomers such as vinyl acetate and vinyl adipate; methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, etc. can be used. , β-hydroxyethyl (meth)acrylate, (2-oxo-1,3-dioxolan-4-yl)-methyl (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, tri(hydroxyethyl)isocyanurate tri(meth)acrylate and other (meth)acrylic monomers; triallyl cyanurate and the like. These are appropriately selected according to the purpose and required characteristics of the curable resin, and one or more kinds thereof may be used.

[0090] The curable resin composition may also contain a solvent. Therefore, in the compounding process, in addition to compounding the curable resin and the polymerization initiator, a solvent may also be compounded. As the solvent, hydrocarbons such as toluene and xylene can be listed; cellosolves such as cellosolves and butyl cellosolves; carbitols such as carbitol and butyl carbitol; cellosolve acetate, methyl carbitol acetate, carbitol acetate (also called ethyl carbitol acetate), butyl carbitol acetate, (di) propylene glycol monomethyl ether acetate, (di) methyl glutarate, (di) methyl succinate, (di) methyl adipate and other esters; ketones such as methyl isobutyl ketone and methyl ethyl ketone; ethers such as (di) ethylene glycol dimethyl ether, etc. As the solvent used in the present invention, esters are preferred, methyl carbitol acetate, ethyl carbitol acetate, butyl carbitol acetate are more preferred, and ethyl carbitol acetate is further preferred. These solvents may be used alone or in combination of two or more, and may be used in an appropriate amount so that the curable resin composition has an optimum viscosity when used.

[0091] The curable resin composition may also contain fillers such as talc, clay, barium sulfate, and silica, coloring pigments, defoamers, coupling agents, leveling agents, sensitizers, release agents, lubricants, plasticizers, antioxidants, ultraviolet absorbers, flame retardants, polymerization inhibitors, tackifiers and other known additives as needed.

[0092] 4. Cured product

[0093] The present invention also includes a cured product formed by curing a curable resin or a curable resin composition. The cured product of the present invention can be obtained by the following manufacturing method, which comprises: a step of obtaining a curable resin composition by the manufacturing method of the curable resin composition of the present invention; and a step of curing the curable resin composition (curing step). In the curing step, the curable resin composition or the curable resin contained therein can be cured by applying heat or light to the curable resin composition.

[0094] In the present invention, after applying a curable resin to a substrate and exposing it to obtain a cured coating film, the unexposed portion is dissolved in an alkaline solution, thereby enabling alkaline development. Examples of usable alkalis include alkali metal compounds such as sodium carbonate, potassium carbonate, sodium hydroxide, and potassium hydroxide; alkaline earth metal compounds such as calcium hydroxide; ammonia; water-soluble organic amines such as monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, monopropylamine, dimethylpropylamine, monoethanolamine, diethanolamine, triethanolamine, ethylenediamine, diethylenetriamine, dimethylaminoethyl methacrylate, and polyethyleneimine, and one or more of these can be used.

[0095] In addition to the method of directly applying the curable resin or curable resin composition of the present invention to the substrate in a liquid state, it can also be used in the form of a dry film formed by pre-applying it to a film such as polyethylene terephthalate and drying it. In this case, as long as the dry film is laminated on the substrate, the film can be peeled off before or after exposure. In addition, it is also possible to obtain a cured product by a CTP (Computer To Plate: direct platemaking machine) system that is recently used in the field of printing platemaking, that is, by the following method, without using a pattern forming film during exposure, but by scanning and exposing the laser directly on the coating film through digitized data to draw.

[0096] The cured product of the present invention is obtained by curing a modified epoxy resin using an epoxy resin having a polydispersity coefficient (Mw / Mn) of 2.8 or more, and therefore has excellent adhesion, is less likely to crack even when subjected to repeated high and low temperature thermal history, and has excellent thermal shock resistance.

[0097] This application claims the benefit of priority based on Japanese Patent Application No. 2022-109176 filed on July 6, 2022. The entire contents of the specification of Japanese Patent Application No. 2022-109176 filed on July 6, 2022 are incorporated herein by reference.

[0098] Example

[0099] Hereinafter, the present invention will be described in more detail by showing embodiments, but the scope of the present invention is not limited thereto, and the situation of changing the implementation within the scope of the gist of the present invention is all included in the technical scope of the present invention. It should be noted that in the following description, as long as there is no special explanation, "part" means "mass part", and "%" means "mass %".

[0100] The weight average molecular weight (Mw), number average molecular weight (Mn), and polydispersity coefficient (Mw / Mn) of the epoxy resin used in the synthesis example were determined by gel permeation chromatography (GPC) using polystyrene as a standard substance. The measurement conditions are as follows.

[0101] Apparatus: Gel Permeation Chromatograph HLC-8320GPC (manufactured by TOSOH Corporation).

[0102] Chromatographic column: TSKgel SuperHZM-M (manufactured by TOSOH Corporation).

[0103] Detector: RI detector for liquid chromatography.

[0104] Measurement temperature: 40℃.

[0105] Solvent: THF (tetrahydrofuran).

[0106] Sample concentration: 0.05g / 10cc.

[0107] Sample side flow rate: 0.6 ml / min.

[0108] (1) Synthesis of curable resin intermediate and curable resin

[0109] (1-1) Synthesis example 1

[0110] 208 parts of o-cresol novolac epoxy resin (cas.29690-82-2; epoxy resin 1) having a polydispersity index of 2.87 (Mn=1330, Mw=3820), a softening point of 91°C, and an epoxy equivalent of 208 g / equivalent were dissolved in 196.5 parts of ethyl carbitol acetate, 1.4 parts of triphenylphosphine were used as a reaction catalyst, 0.6 parts of hydroquinone were used as a polymerization inhibitor, 72.8 parts of acrylic acid were added as an unsaturated monobasic acid, and the mixture was reacted at 110°C for 15 hours to obtain a curable resin intermediate 1. Subsequently, 84.1 parts of tetrahydrophthalic anhydride were added as a polyacid anhydride, and the mixture was reacted with the curable resin intermediate 1 at 100°C for 8 hours. The temperature of the obtained reaction solution was lowered to 90°C, and the mixture was filtered using a 300-mesh stainless steel wire mesh (mesh size of about 50 μm). As a result, an ethyl carbitol acetate solution (A-1) containing 65% of curable resin 1 having an acid value of 90 mgKOH / g and a double bond equivalent of 360 g / equivalent was obtained.

[0111] The curable resin 1 has the following structural units (1) and (2).

[0112] [Chemical formula 1]

[0113]

[0114] (1-2) Synthesis example 2

[0115] 208 parts of o-cresol novolac epoxy resin (cas.29690-82-2: epoxy resin 2) having a polydispersity index of 3.03 (Mn=1270, Mw=3850), a softening point of 94°C, and an epoxy equivalent of 208 g / equivalent were dissolved in 196.5 parts of ethyl carbitol acetate, 1.4 parts of triphenylphosphine were used as a reaction catalyst, 0.6 parts of hydroquinone were used as a polymerization inhibitor, 72.8 parts of acrylic acid were added as an unsaturated monobasic acid, and the mixture was reacted at 110°C for 15 hours to obtain a curable resin intermediate 2. Subsequently, 84.1 parts of tetrahydrophthalic anhydride were added as a polyacid anhydride, and the mixture was reacted with the curable resin intermediate 2 at 100°C for 8 hours. The temperature of the obtained reaction solution was lowered to 90°C, and the mixture was filtered using a 300-mesh stainless steel wire mesh (mesh size of about 50 μm). As a result, an ethyl carbitol acetate solution (A-2) containing 65% of curable resin 2 having an acid value of 91 mgKOH / g and a double bond equivalent of 360 g / equivalent was obtained. Curable resin 2 has the structural units (1) and (2).

[0116] (1-3) Synthesis example 3

[0117] 208 parts of o-cresol novolac epoxy resin (epoxy resin 2) used in Synthesis Example 2 were dissolved in 196.5 parts of ethyl carbitol acetate, 1.5 parts of triphenylphosphine were used as a reaction catalyst, 0.6 parts of hydroquinone were used as a polymerization inhibitor, 41.5 parts of p-hydroxyphenyl-2-ethanol were added as a phenolic compound having an alcoholic hydroxyl group, and 51.2 parts of acrylic acid were added as an unsaturated monobasic acid, and the mixture was reacted at 110°C for 15 hours to obtain a curable resin intermediate 3. Subsequently, 64.3 parts of tetrahydrophthalic anhydride were added as a polyacid anhydride, and the mixture was reacted with the curable resin intermediate 3 at 100°C for 5 hours. The temperature of the obtained reaction solution was lowered to 90°C, and the mixture was filtered using a 300-mesh stainless steel wire mesh (mesh size of about 50 μm). As a result, an ethyl carbitol acetate solution (A-3) containing 65% of a curable resin 3 having an acid value of 69 mgKOH / g and a double bond equivalent of 520 g / equivalent was obtained.

[0118] The curable resin 3 has the following structural units (1), (2), and (3).

[0119] [Chemical formula 2]

[0120]

[0121] (1-4) Synthesis Example 4

[0122] 203 parts of o-cresol novolac epoxy resin (cas.29690-82-2; epoxy resin 3) with a polydispersity index of 2.92 (Mn=1100, Mw=3210), a softening point of 85°C, and an epoxy equivalent of 203 g / equivalent were dissolved in 192.9 parts of ethyl carbitol acetate, 1.4 parts of triphenylphosphine were used as a reaction catalyst, 0.6 parts of hydroquinone were used as a polymerization inhibitor, 72.8 parts of acrylic acid were added as an unsaturated monobasic acid, and the mixture was reacted at 110°C for 15 hours to obtain a curable resin intermediate 4. Subsequently, 82.6 parts of tetrahydrophthalic anhydride were added as a polyacid anhydride, and the mixture was reacted with the curable resin intermediate 4 at 100°C for 8 hours. The temperature of the obtained reaction solution was lowered to 90°C, and the mixture was filtered using a 300-mesh stainless steel wire mesh (mesh size of about 50 μm). As a result, an ethyl carbitol acetate solution (A-4) containing 65% of curable resin 4 having an acid value of 91 mgKOH / g and a double bond equivalent of 360 g / equivalent was obtained. Curable resin 4 has the structural units (1) and (2).

[0123] (1-5) Comparative Synthesis Example 1

[0124] 208 parts of the o-cresol novolac epoxy resin (epoxy resin 1) used in Synthesis Example 1 was dissolved in 196.5 parts of ethyl carbitol acetate, 1.4 parts of triphenylphosphine was used as a reaction catalyst, 0.6 parts of methylhydroquinone was used as a polymerization inhibitor, 72.8 parts of acrylic acid was added as an unsaturated monobasic acid, and the mixture was reacted at 110°C for 15 hours to obtain a curable resin intermediate 5. Next, 84.1 parts of tetrahydrophthalic anhydride was added as a polyacid anhydride, and the mixture was reacted with the curable resin intermediate 5 at 100°C for 8 hours. The temperature of the obtained reaction solution was lowered to 90°C, and the mixture was filtered using a 300-mesh stainless steel wire mesh (mesh size of about 50 μm). As a result, an ethyl carbitol acetate solution (B-1) containing 65% of a curable resin 5 having an acid value of 89 mgKOH / g and a double bond equivalent of 360 g / equivalent was obtained. The curable resin 5 has the above-mentioned structural units (1) and (2).

[0125] (1-6) Comparative Synthesis Example 2

[0126] 209 parts of o-cresol novolac epoxy resin (cas.29690-82-2; epoxy resin 4) with a polydispersity index of 2.72 (Mn=1340, Mw=3640), a softening point of 92.5°C, and an epoxy equivalent of 209 g / equivalent were dissolved in 197.2 parts of ethyl carbitol acetate, 1.4 parts of triphenylphosphine were used as a reaction catalyst, 0.6 parts of hydroquinone were used as a polymerization inhibitor, 72.8 parts of acrylic acid were added as an unsaturated monobasic acid, and the mixture was reacted at 110°C for 15 hours to obtain a curable resin intermediate 6. Subsequently, 84.4 parts of tetrahydrophthalic anhydride were added as a polyacid anhydride, and the mixture was reacted at 100°C for 8 hours. The temperature of the obtained reaction solution was lowered to 90°C, and the mixture was filtered using a 300-mesh stainless steel wire mesh (mesh size of about 50 μm). As a result, an ethyl carbitol acetate solution (B-2) containing 65% of curable resin 6 having an acid value of 90 mgKOH / g and a double bond equivalent of 370 g / equivalent was obtained. Curable resin 6 has the structural units (1) and (2).

[0127] (1-7) Comparative Synthesis Example 3

[0128] 212 parts of o-cresol novolac epoxy resin (cas.29690-82-2; epoxy resin 5) having a polydispersity index of 2.59 (Mn=1380, Mw=3570), a softening point of 94°C, and an epoxy equivalent of 212 g / equivalent were dissolved in 199.3 parts of ethyl carbitol acetate, 1.4 parts of triphenylphosphine were used as a reaction catalyst, 0.6 parts of hydroquinone were used as a polymerization inhibitor, 72.8 parts of acrylic acid were added as an unsaturated monobasic acid, and the mixture was reacted at 110°C for 15 hours to obtain a curable resin intermediate 7. Subsequently, 85.3 parts of tetrahydrophthalic anhydride were added as a polyacid anhydride, and the mixture was reacted with the curable resin intermediate 7 at 100°C for 8 hours. The temperature of the obtained reaction solution was lowered to 90°C, and the mixture was filtered using a 300-mesh stainless steel wire mesh (mesh size of about 50 μm). As a result, a comparative ethyl carbitol acetate solution (B-3) containing 65% of curable resin 7 having an acid value of 91 mgKOH / g and a double bond equivalent of 370 g / equivalent was obtained. Curable resin 7 has the structural units (1) and (2).

[0129] (2) Preparation and Evaluation Method of Curable Resin Composition (2-1) Preparation Method

[0130] Using the curable resin solutions obtained in Synthesis Examples 1 to 4 and Comparative Synthesis Examples 1 to 3, curable resin compositions were prepared according to the formulations shown in Table 1, and evaluated by the following methods as Examples 1 to 4 and Comparative Examples 1 to 3, respectively.

[0131] [Evaluation of detackification]

[0132] Each curable resin composition was applied to a copper plate having a thickness of 0.5 mm at a thickness of 20 to 30 μm, and dried in a hot air circulation drying oven at 80° C. for 30 minutes to obtain a coating film. Next, a negative film was pressed onto the coating film and subjected to an ultraviolet exposure device at 2 J / cm 2 After exposure, the state when the negative film was peeled off was evaluated according to the following criteria.

[0133] ◎: Can be peeled off without peeling sound.

[0134] ○: There was a slight peeling sound, but no trace of the negative film remained on the coating film.

[0135] ×: There is a peeling sound and traces of the negative film remain on the coating film.

[0136] [Developability Evaluation]

[0137] Each curable resin composition was applied to a copper plate having a thickness of 0.5 mm at a thickness of 20 to 30 μm, and dried in a hot air circulation drying oven at 80° C. for 30 minutes to obtain a coating film. Next, a negative film was pressed onto the coating film and subjected to an ultraviolet exposure device at 2 J / cm 2 The negative film was peeled off, and developed using a 1% Na2CO3 aqueous solution at 30°C for 80 seconds, and the presence of the remaining resin coating film was evaluated by visual inspection based on the following criteria.

[0138] ○: Good developability (no deposits at all on the unexposed portion).

[0139] ×: Poor developability (adherent matter remains in the unexposed portion).

[0140] [Adhesion Evaluation]

[0141] A dry coating film was formed in the same manner as in the evaluation of detackification, and an ultraviolet exposure device was used to expose the film at 2 J / cm 2 The film was then heated at 150°C for 30 minutes as a high temperature condition. The tape was then attached to the coating film in a manner such that the size of the attached surface was 24 mm × 30 mm. The tape was instantly peeled off while the end of the tape was kept at a right angle to the coating film surface. The peeling test was performed, and the adhesion was visually evaluated according to the following criteria.

[0142] ◎: The adhesion of the coating film is good (no peeling).

[0143] ○: The peeling amount is less than 20% of the coating film (adherence surface).

[0144] ×: The peeling amount is 20% or more of the coating film (adherence surface).

[0145] [Thermal Cycle Test Resistance (TCT Resistance Evaluation)]

[0146] The dried coating film was formed, exposed and developed in the same manner as in the evaluation of developability to obtain a cured product. The cured product was heated at 150°C for 1 hour to prepare a test substrate. The test substrate was used to perform a hot and cold cycle test with 15 minutes at -65°C and 15 minutes at 150°C as one cycle. The appearance was observed every 100 cycles and evaluated visually according to the following criteria.

[0147] ◎: No cracks were observed even after 200 cycles.

[0148] ○: Cracks were observed at 200 cycles.

[0149] ×: Cracks were observed at 100 cycles.

[0150] (3) Results

[0151] The test evaluation results of each curable resin composition are shown in Table 1. In Examples 1 to 4 using an o-cresol novolac epoxy resin having a polydispersity index of 2.8 or more as the epoxy resin and using benzene directly bonded with two or more hydroxyl groups as a polymerization inhibitor, the obtained cured product has excellent adhesion and thermal cycle test resistance (TCT resistance), and also excellent detackification and developability. In Example 3 in which p-hydroxyphenyl-2-ethanol is added as a phenolic compound having an alcoholic hydroxyl group, the adhesion and thermal cycle test resistance (TCT resistance) are further improved. On the other hand, in Comparative Example 1 using methylhydroquinone as a polymerization inhibitor, the obtained cured product has poor detackification and thermal cycle test resistance (TCT resistance). In addition, in Comparative Examples 2 and 3 using an o-cresol novolac epoxy resin having a polydispersity index of less than 2.8, the obtained cured product has poor adhesion and thermal cycle test resistance (TCT resistance), and the detackification of Comparative Example 2 is even worse.

[0152] [Table 1]

[0153]

[0154] *Monomer (free radical polymerizable compound): dipentaerythritol hexaacrylate.

[0155] Polymerization initiator: Irgacure (registered trademark) 907 (photopolymerization initiator manufactured by BASF Japan).

[0156] Industrial Applicability

[0157] The curable resin intermediate, curable resin and curable resin composition of the present invention can be preferably used for various applications for alkali-developable image formation, such as printing plate making, color filter protective film, color filter, black matrix and other liquid crystal display panel manufacturing.

Claims

1. A method for producing a curable resin intermediate, comprising: A step of reacting an epoxy resin having a polydispersity coefficient (Mw / Mn) of 2.8 or more with an unsaturated monobasic acid in the presence of benzene or naphthalene to which two or more hydroxyl groups are directly bonded.

2. The manufacturing method according to claim 1, wherein: The epoxy resin is a cresol novolac type epoxy resin.

3. The manufacturing method according to claim 1, wherein: The epoxy resin has a weight average molecular weight of more than 3000, a softening point of 85 to 110° C., and an epoxy equivalent of 150 to 300 g / equivalent.

4. The manufacturing method according to claim 1, wherein: In the step of reacting the epoxy resin with the unsaturated monobasic acid, the epoxy resin is also reacted with a phenolic compound having an alcoholic hydroxyl group.

5. A method for producing a curable resin, comprising: A step of producing a curable resin intermediate by the method according to any one of claims 1 to 4, and then reacting the obtained curable resin intermediate with a polybasic acid anhydride.

6. The manufacturing method according to claim 5, wherein: The double bond equivalent of the curable resin is 300 to 620 g / equivalent.

7. The manufacturing method according to claim 5, wherein: The acid value of the curable resin is 50 to 100 mgKOH / g.

8. A method for producing a curable resin composition, comprising: After producing the curable resin by the production method according to claim 5, a step of mixing the obtained curable resin, a polymerization initiator and a monomer to be added as needed.

9. A method for producing a solidified product, wherein: After the curable resin composition is produced by the production method according to claim 8, the obtained curable resin composition is cured.

10. A curable resin, wherein: The curable resin comprises: an epoxy resin-derived portion having a structure in which an epoxy group of the epoxy resin is ring-opened; an unsaturated monobasic acid residue bonded to a carbon atom of the ring-opened portion of the epoxy group; and a polybasic acid anhydride residue bonded to an oxygen atom of the ring-opened portion of the epoxy group. The polydispersity coefficient (Mw / Mn) of the epoxy resin-derived portion is 2.8 or more, and the curable resin contains benzene or naphthalene to which two or more hydroxyl groups are directly bonded.

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