JP7297338B2 - Curable resin composition and method for producing the same - Google Patents

Description

The present invention particularly relates to a curable resin composition that can be suitably used for liquid crystal display elements such as liquid crystal displays.

The method of manufacturing the liquid crystal display cell includes a method of manufacturing a liquid crystal display cell by dropping a liquid crystal on the inside of a weir of a sealant formed on one base material and then bonding the other base material together, or a method of applying a sealant. Sometimes, there is a method of providing a portion to be an injection port, injecting liquid crystal after bonding base materials together, and then sealing the injection port to manufacture a liquid crystal display cell. Since lamination includes a step of heating, a thermosetting resin composition containing an epoxy group-containing resin as a heat-curing component is used as a sealant composition for manufacturing a liquid crystal display cell.

As a curing agent for the epoxy group-containing resin, a latent curing agent capable of reacting with the epoxy group or the like when heat, light, pressure, or the like is applied is used (Patent Document 1, Patent Document 2, Patent Document 3).
Patent Document 2 discloses a curable epoxy resin composition containing a latent curing agent obtained by surface-treating fine powder of epoxy and/or polyisocyanate-modified amine with a reactant of water, polyisocyanate and epoxy resin. .
Patent Literature 3 discloses a sealant for a liquid crystal dripping method containing a hydrazide-based curing agent coated with a compound having an isocyanate group.

JP-A-2001-133794 JP 2010-90295 A JP 2012-93582 A

In Patent Document 1, when a curing agent that cures at a low temperature is used, the curing reaction starts gradually even at room temperature, which poses a problem of poor liquid stability.
The latent curing agent reacted with the isocyanate compound described in Patent Document 2 had to be prepared in advance before being mixed with the curable resin.
In Patent Document 3, the storage stability of the composition was confirmed, but the curability was not confirmed. In addition, when the sealant composition is usually filled in a syringe and applied to a substrate, and the syringe is washed with an organic solvent such as acetone and used repeatedly, the use of an epoxy adduct curing agent results in poor washability. There was a problem.
Accordingly, an object of the present invention is to provide a curable resin composition that is excellent in storage stability, curability and washability.

The present invention has the following configurations.
[1] A curable resin composition containing a curable resin (A), a latent curing agent (B) and an isocyanate compound (C),
Part or all of the latent curing agent (B) and part or all of the isocyanate compound (C) may react,
The latent curing agent (B) is selected from the group consisting of (b1) a carbazide compound, (b2) a compound obtained by adducting an imidazole compound to an epoxy resin, and (b3) a polyvalent amine compound consisting of an epoxy resin, an isocyanate compound, and urea. (provided that the polyvalent amine compound in (b3) does not contain hydrazine, hydrazide compound, and (b1) carbazide compound), (b4) two or more hydrazide compounds (b5) mixed crystals of one or more mono- or polyvalent amine compounds and one or more hydrazide compounds, and (b6) mixed crystals of one or more imidazole compounds and one or more hydrazide compounds A curable resin composition that is at least one selected from the group consisting of:
[2] The curable resin composition according to [1], which contains 0.02 to 28 parts by mass of the isocyanate compound (C) with respect to 100 parts by mass of the latent curing agent (B).
[3] The curable resin composition according to [1] or [2], further comprising a photoinitiator (D).
[4] The curable resin composition according to any one of [1] to [3], which is a sealant composition for liquid crystal display elements.
[5] A method for producing a curable resin composition containing a curable resin (A), a latent curing agent (B) and an isocyanate compound (C),
A step of mixing the curable resin (A), the latent curing agent (B) and the isocyanate compound (C) without pre-reacting the latent curing agent (B) and the isocyanate compound (C);
The latent curing agent (B) is selected from the group consisting of (b1) a carbazide compound, (b2) a compound obtained by adducting an imidazole compound to an epoxy resin, and (b3) a polyvalent amine compound consisting of an epoxy resin, an isocyanate compound, and urea. (provided that the polyvalent amine compound in (b3) does not contain hydrazine, hydrazide compound, and (b1) carbazide compound), (b4) two or more hydrazide compounds (b5) mixed crystals of one or more mono- or polyvalent amine compounds and one or more hydrazide compounds, and (b6) mixed crystals of one or more imidazole compounds and one or more hydrazide compounds is at least one selected from the group consisting of
A method for producing a curable resin composition.
[6] A liquid crystal display panel obtained using the curable resin composition of [1] to [4].
[7] A method for manufacturing a liquid crystal display panel, wherein the curable resin composition of [1] to [4] is photocured and/or thermally cured in the liquid crystal dropping method.

The curable resin composition of the present invention is excellent in storage stability, curability and washability.

The curable resin composition is a curable resin composition containing a curable resin (A), a latent curing agent (B) and an isocyanate compound (C),
Part or all of the latent curing agent (B) and part or all of the isocyanate compound (C) may react,
The latent curing agent (B) is a carbazide compound, a compound obtained by adducting imidazole to an epoxy resin, and a polyvalent amine compound to at least one compound selected from the group consisting of an epoxy resin, an isocyanate compound, and urea. mixed crystals of two or more hydrazide compounds, mixed crystals of one or more polyvalent amine compounds and one or more hydrazide compounds, and mixed crystals of one or more imidazole compounds and one or more hydrazide compounds A curable resin composition that is at least one selected from the group consisting of

1. Curing resin (A)
Curable resins include epoxy resins and resins having at least one unsaturated bond in the molecule (excluding epoxy resins having unsaturated bonds).

〔Epoxy resin〕
Known epoxy resins can be used, and examples thereof include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, and cycloaliphatic resin. Examples include epoxy resins, glycidyl ester-based resins, glycidylamine-based epoxy resins, heterocyclic epoxy resins, urethane-modified epoxy resins, and the like. Among these, it is preferable to use a bisphenol A type epoxy resin, a cresol novolac type epoxy resin, or the like.

Also, the epoxy resin may be an epoxy resin having an unsaturated bond. As an epoxy resin having such an unsaturated bond, there is a partially esterified epoxy resin obtained by reacting an epoxy resin with (meth)acrylic acid, in which a part of the epoxy group is modified with (meth)acrylic acid. mentioned. Such resins are described, for example, in JP-A-2012-77202. As the epoxy resin having an unsaturated bond, (meth)acrylic acid is preferably added in an amount of 10 to 90 equivalent%, more preferably 20 to 80 equivalent%, and still more preferably 30 to 70%, based on 1 equivalent of the epoxy group of the epoxy resin. Preference is given to partially esterified epoxy resins obtained by reacting equivalent %, particularly preferably 40 to 60 equivalent % of (meth)acrylic acid.
Epoxy resins may be used singly or in combination.

For the partially esterified epoxy resin, for example, first, bisphenol A type epoxy resin and acrylic acid or methacrylic acid are mixed in the presence of a basic catalyst in accordance with a conventional method to obtain 0.9 to 1 carboxylic acid group per 2 equivalents of epoxy group. To this reaction product, add toluene in a mass ratio of about 4 times and the same amount of pure water, stir at 60 to 80 ° C. for 1 hour, and then leave to stand to obtain an organic A layer and an aqueous layer are separated, and the aqueous layer is removed. This operation is repeated 3 to 5 times, and finally the organic layer is recovered and the remaining toluene is removed by vacuum distillation to obtain a partially esterified epoxy resin that has been treated to reduce water-soluble ionic substances. can. Specific examples of the above-mentioned bisphenol A type epoxy resin include Epikote 828, 834, 1001 and 1004 (manufactured by Mitsubishi Chemical Corporation) and Epiclon 850, 860 and 4055 (manufactured by DIC Corporation). As these raw material resins, resins subjected to treatment for reducing water-soluble ionic substances (also referred to as "high purification treatment"), such as Epiclon 850S (manufactured by DIC Corporation), are suitable. An example of the partially esterified epoxy resin is PR-850CRP (manufactured by KSM).

[Resin having at least one unsaturated bond in the molecule]
The resin composition may contain a resin having at least one unsaturated bond in its molecule (except epoxy resin having an unsaturated bond). Examples of resins having at least one unsaturated bond in the molecule include styrene derivatives, ethylene derivatives, maleimide derivatives, (meth)acrylic acid derivatives and the like. Among them, it is preferable to use a (meth)acrylic acid derivative having at least one (meth)acryloyl group in the molecule.

Specific examples of (meth)acrylic acid derivatives include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, and t (meth)acrylate. - (meth)acrylic acid alkyl esters such as butyl; (meth)acrylic acid aryl esters such as phenyl (meth)acrylate; (meth)acrylic acid aralkyl esters such as benzyl (meth)acrylate; methoxy (meth)acrylate Alkoxyalkyl (meth)acrylates such as ethyl, ethoxyethyl (meth)acrylate, propoxyethyl (meth)acrylate, butoxyethyl (meth)acrylate; 2-hydroxyethyl (meth)acrylate, (meth)acrylic Hydroxyl group-containing (meth)acrylic acid esters such as 3-hydroxypropyl acid, 2-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; lipids such as cyclohexyl (meth)acrylate; Examples thereof include (meth)acrylic acid esters of cyclic alcohols; epoxy (meth)acrylic acid (also called “epoxy (meth)acrylate”) obtained by modifying a resin having a glycidyl group with (meth)acrylic acid; (Meth)acrylic acid as used herein means both acrylic acid and methacrylic acid.

When an epoxy resin and a resin having at least one unsaturated bond in the molecule are used in combination, the blending amount of the epoxy resin and the resin having at least one unsaturated bond in the molecule is determined by the resin composition. It can be determined as appropriate according to the purpose of the cured product obtained by curing an object. When the resin having at least one unsaturated bond in the molecule is a (meth)acrylic acid derivative having at least one (meth)acryloyl group in the molecule, per equivalent of the epoxy group, (meth ) acryloyl group is preferably blended in an amount of 0.1 to 9.0 equivalents, and it is more preferably blended in an amount of (meth)acryloyl group of 0.3 to 4.0 equivalents.

2. Latent curing agent (B)
The latent curing agent (B) is selected from the group consisting of (b1) a carbazide compound, (b2) a compound obtained by adducting imidazole to an epoxy resin, and (b3) a polyvalent amine compound consisting of an epoxy resin, an isocyanate compound, and urea. (b4) mixed crystals of two or more hydrazide compounds, (b5) mixed crystals of one or more polyvalent amine compounds and one or more hydrazide compounds, and (b6) ) At least one compound selected from the group consisting of mixed crystals of one or more imidazole compounds and one or more hydrazide compounds. In (b3) compounds obtained by adducting polyvalent amine compounds to epoxy resins and isocyanate compounds, the polyvalent amine compounds do not contain hydrazine, hydrazide compounds, and (b1) carbazide compounds.

（式中、Ｘ^１は、Ｃ_１～Ｃ_１２アルキレン、１つ若しくはそれ以上のＯ原子（酸素原子）で非連続的に中断されたＣ_２～Ｃ_１２アルキレン、Ｃ_１～Ｃ_１２アルキレンオキシカルボニルアルキレン、Ｃ_３～Ｃ_１２シクロアルキレン、Ｃ_１～Ｃ_１２アルキレン－Ｃ_３～Ｃ_１２シクロアルキレン、Ｃ_１～Ｃ_１２アルキレン－Ｃ_３～Ｃ_１２シクロアルキレン－Ｃ_１～Ｃ_１２アルキレン、Ｃ_３～Ｃ_１２シクロアルキレン－Ｃ_１～Ｃ_１２アルキレン－Ｃ_３～Ｃ_１２シクロアルキレン、ジＣ_３～Ｃ_１２シクロアルカンジイル、Ｃ_６～Ｃ_１４アリーレン、Ｃ_１～Ｃ_４アルキレン－Ｃ_６～Ｃ_１４アリーレン－Ｃ_１～Ｃ_４アルキレン、又はＣ_６～Ｃ_１４アリーレン－Ｃ_１～Ｃ_４アルキレン－Ｃ_６～Ｃ_１４アリーレン（ここで、アルキレンは、直鎖又は分岐鎖であり、ハロゲンで置換されていてもよく、Ｃ_３～Ｃ_１２シクロアルキレン又はＣ_６～Ｃ_１４アリーレンは、非置換であるか、又はハロゲン若しくはＣ_１～Ｃ_４アルキルで置換されている）である。）

（式中、Ｘ^２は、Ｃ_１～Ｃ_１２アルキル、１つ若しくはそれ以上のＯ原子（酸素原子）で非連続的に中断されたＣ_２～Ｃ_１２アルキル、Ｃ_１～Ｃ_１２アルキルオキシカルボニルアルキレン、Ｃ_３～Ｃ_１２シクロアルキル、Ｃ_１～Ｃ_１２アルキル－Ｃ_３～Ｃ_１２シクロアルキレン、Ｃ_３～Ｃ_１２シクロアルキル－Ｃ_１～Ｃ_１２アルキレン－Ｃ_３～Ｃ_１２シクロアルキレン、Ｃ_６～Ｃ_１４アリール、Ｃ_１～Ｃ_４アルキル－Ｃ_６～Ｃ_１４アリーレン、Ｃ_６～Ｃ_１４アリール－Ｃ_１～Ｃ_４アルキレン－Ｃ_６～Ｃ_１４アリーレン（ここで、アルキレンは、直鎖又は分岐鎖であり、ハロゲンで置換されていてもよく、Ｃ_３～Ｃ_１２シクロアルキル、Ｃ_３～Ｃ_１２シクロアルキレン、Ｃ_６～Ｃ_１４アリール又はＣ_６～Ｃ_１４アリーレンは、非置換であるか、又はハロゲン若しくはＣ_１～Ｃ_４アルキルで置換されている。）、又は（メタ）アクリロイルオキシアルキルである。） [(b1) carbazide compound]
Carbazide compounds include disemicarbazide compounds represented by the following formula (Ib) and semicarbazide compounds represented by the following formula (IIb).

(Wherein, X ¹ is C ₁ -C ₁₂ alkylene, C ₂ -C ₁₂ alkylene interrupted discontinuously by one or more O atoms (oxygen atoms), C ₁ -C ₁₂ alkyleneoxycarbonyl alkylene, C ₃ -C ₁₂ cycloalkylene, C ₁ -C ₁₂ alkylene-C ₃ -C ₁₂ cycloalkylene, C ₁ -C ₁₂ alkylene-C ₃ -C ₁₂ cycloalkylene-C ₁ -C ₁₂ alkylene, C ₃ - C ₁₂ cycloalkylene-C ₁ -C ₁₂ alkylene-C ₃ -C ₁₂ cycloalkylene, diC ₃ -C ₁₂ cycloalkanediyl, C ₆ -C ₁₄ arylene, C ₁ -C ₄ alkylene-C ₆ -C ₁₄ arylene —C ₁ -C ₄ alkylene, or C ₆ -C ₁₄ arylene -C ₁ -C ₄ alkylene-C ₆ -C ₁₄ arylene, wherein alkylene is linear or branched and substituted with halogen may be C ₃ -C ₁₂ cycloalkylene or C ₆ -C ₁₄ arylene are unsubstituted or substituted with halogen or C ₁ -C ₄ alkyl).

(wherein X ² is C ₁ -C ₁₂ alkyl, C ₂ -C ₁₂ alkyl discontinuously interrupted by one or more O atoms (oxygen atoms), C ₁ -C ₁₂ alkyloxycarbonyl alkylene, C ₃ -C ₁₂ cycloalkyl, C ₁ -C ₁₂ alkyl-C ₃ -C ₁₂ cycloalkylene, C ₃ -C ₁₂ cycloalkyl-C ₁ -C ₁₂ alkylene-C ₃ -C ₁₂ cycloalkylene, C ₆ -C ₁₄ aryl, C ₁ -C ₄ alkyl-C ₆ -C ₁₄ arylene, C ₆ -C ₁₄ aryl-C ₁ -C ₄ alkylene-C ₆ -C ₁₄ arylene (where alkylene is linear or branched) chain, optionally substituted with halogen, wherein C ₃ -C ₁₂ cycloalkyl, C ₃ -C ₁₂ cycloalkylene, C ₆ -C ₁₄ aryl or C ₆ -C ₁₄ arylene is unsubstituted or or substituted with halogen or C ₁ -C ₄ alkyl.), or (meth)acryloyloxyalkyl.)

As used herein, “C ₁ -C ₁₂ alkyl”, alone or in combination with any other term, is straight or branched chain, optionally substituted with halogen, one or more may be discontinuously interrupted by O atoms (oxygen atoms) of , preferably straight-chain. The carbon number range of alkyl is C ₁ to C ₁₂ , more preferably C ₁ to C ₈ , still more preferably C ₁ to C ₆ , and particularly preferably C ₁ to C ₄ . Specific examples include methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n- Linear ones such as dodecyl, and branched ones such as isopropyl, isobutyl, sec-butyl, t-butyl, 2-methylbutyl, isooctyl, t-octyl, 2-ethylhexyl and t-nonyl. Halogen includes fluorine, chlorine, bromine and iodine atoms. Halogen as a substituent is preferably a fluorine atom or a chlorine atom, more preferably a fluorine atom. The number of substitutions is 1 to 12, preferably 1 to 6, more preferably 1 to 4, particularly preferably 1 to 3.

As used herein, “C ₁ -C ₁₂ alkylene”, alone or in combination with other terms, is straight or branched chain, optionally substituted with halogen, one or more may be discontinuously interrupted by NH (imino group) or O atom (oxygen atom) (H atom (hydrogen atom) bonded to N atom (nitrogen atom) is an amino group or C ₁ to C ₁₂ (may be substituted with an alkylamino group of ), preferably straight-chain. Alkylene has a carbon number range of C ₁ to C ₁₂ , more preferably C ₁ to C ₈ , still more preferably C ₁ to C ₆ , and particularly preferably C ₁ to C ₄ . Specific examples include methylene, ethylene, trimethylene, propylene, tetramethylene, 1-methyltrimethylene, 2-methyltrimethylene, 3-methyltrimethylene, pentamethylene, 1-methyltetramethylene, 4-methyltetramethylene, methylene, hexamethylene, 5-methylpentamethylene, heptamethylene, octamethylene, nonamethylene, decamethylene, undecamethylene, dodecamethylene and the like. Halogen includes fluorine, chlorine, bromine and iodine atoms. Halogen as a substituent is preferably a fluorine atom or a chlorine atom, more preferably a fluorine atom. The number of substitutions is 1 to 12, preferably 1 to 6, more preferably 1 to 4, particularly preferably 1 to 3.

In this specification, the range of carbon number of alkyloxy or alkyleneoxy in "C ₁ -C ₁₂ alkyloxycarbonylalkylene" or "C ₁ -C ₁₂ alkyleneoxycarbonylalkylene" is C ₁ -C ₁₂ , and more C ₁ to C ₈ are preferred, C ₁ to C ₆ are more preferred, and C ₁ to C ₄ are particularly preferred. Specific examples include methoxycarbonylmethylene, ethoxycarbonylmethylene, n-propoxycarbonylmethylene, n-butoxycarbonylmethylene, n-pentyloxycarbonylmethylene, n-hekyloxycarbonylmethylene, n-heptyloxycarbonylmethylene, n Straight chain such as -octyloxycarbonylmethylene, n-nonyloxycarbonylmethylene, n-decyloxycarbonylmethylene, n-undecyloxycarbonylmethylene, n-dodecyloxycarbonylmethylene, isopropoxycarbonylmethylene, isobutoxycarbonylmethylene , sec-butoxycarbonylmethylene, t-butoxycarbonylmethylene, 2-methylbutoxycarbonylmethylene, isooctyloxycarbonylmethylene, t-octyloxycarbonylmethylene, 2-ethylhexyloxycarbonylmethylene and the like.

As used herein, alone or in combination with other terms, the carbon number range for " _C3 - _C12 cycloalkyl" is _C3 - _C12 , more preferably _C3 - _C8 , and further The range of C ₃ to C ₆ is preferred, and the range of C ₄ to C ₆ is particularly preferred. Specific examples include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl and cyclododecyl. C ₃ -C ₁₂ cycloalkyl is preferably cyclopentyl or cyclohexyl. C ₃ -C ₁₂ cycloalkyl may be unsubstituted or substituted with halogen or C ₁ -C ₄ alkyl, halogen including fluorine, chlorine, bromine, iodine atoms . Halogen as a substituent is preferably a fluorine atom or a chlorine atom, more preferably a chlorine atom. C ₁ -C ₄ alkyl as substituents include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and t-butyl. C ₁ -C ₄ alkyl as a substituent is preferably methyl, ethyl or n-propyl, more preferably methyl or ethyl. When having a substituent, the number of substituents is 1 to 5, preferably 1 to 3, more preferably 1 to 2, and particularly preferably 1.

As used herein, alone or in combination with other terms, the carbon number range for " _C3 - _C12 cycloalkylene" is _C3 - _C12 , more preferably _C3 - _C8 , and further The range of C ₃ to C ₆ is preferred, and the range of C ₄ to C ₆ is particularly preferred. Specific examples include cyclopropylene, cyclobutylene, cyclopentylene, cyclohexylene, cycloheptylene, cyclooctylene, cyclononylene, cyclodecylene, cycloundecylene and cyclododecylene. C ₃ -C ₁₂ cycloalkylene is preferably cyclopentylene or cyclohexylene. C ₃ -C ₁₂ cycloalkylene may be unsubstituted or substituted with halogen or C ₁ -C ₄ alkyl, halogen including fluorine, chlorine, bromine and iodine atoms . Halogen as a substituent is preferably a fluorine atom or a chlorine atom, more preferably a chlorine atom. C ₁ -C ₄ alkyl as substituents include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and t-butyl. C ₁ -C ₄ alkyl as a substituent is preferably methyl, ethyl or n-propyl, more preferably methyl or ethyl. When having a substituent, the number of substituents is 1 to 4, preferably 1 to 3, more preferably 1 to 2, and particularly preferably 1.

As used herein, “C ₆ -C ₁₄ aryl”, alone or in combination with other terms, is a monovalent radical having at least one aromatic ring. Specific examples thereof include phenyl, biphenyl, naphthyl, anthranyl, phenanthrene and the like. Phenyl, biphenyl or naphthyl is preferred, and phenyl or naphthyl is more preferred. C ₆ -C ₁₄ aryl may be unsubstituted or substituted with halogen or C ₁ -C ₄ alkyl, halogen including fluorine, chlorine, bromine and iodine atoms. Halogen as a substituent is preferably a fluorine atom or a chlorine atom, more preferably a chlorine atom. C ₁ -C ₄ alkyl as substituents include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and t-butyl. C ₁ -C ₄ alkyl as a substituent is preferably methyl, ethyl or n-propyl, more preferably methyl or ethyl. When having a substituent, the number of substituents is 1 to 5, preferably 1 to 3, more preferably 1 to 2, and particularly preferably 1.

As used herein, “C ₆ -C ₁₄ arylene”, alone or in combination with other terms, is a divalent radical having at least one aromatic ring. Specific examples thereof include phenylene, naphthylene, anthranylene, phenanthranylene, and the like. Phenylene and naphthylene are preferred, and phenylene and naphthylene are more preferred. C ₆ -C ₁₄ arylene may be unsubstituted or substituted with halogen or C ₁ -C ₄ alkyl, halogen including fluorine, chlorine, bromine and iodine atoms. Halogen as a substituent is preferably fluorine, chlorine or bromine, more preferably fluorine or chlorine. C ₁ -C ₄ alkyl as substituents include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and t-butyl. C ₁ -C ₄ alkyl as a substituent is preferably methyl, ethyl or n-propyl, more preferably methyl or ethyl. When having a substituent, the number of substituents is 1 to 4, preferably 1 to 3, more preferably 1 to 2, and particularly preferably 1.

[(b2) Compound obtained by adducting an imidazole compound to an epoxy resin]
The imidazole compound is an imidazole compound that does not have a primary amino group in the molecule. Examples of such imidazole compounds include compounds containing an imidazole ring in which the nitrogen atom at position 1 is unsubstituted, such as 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4, 5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and 2-methylimidazoline; and imidazole compounds substituted at the nitrogen atom at position 1, such as 1,2-dimethylimidazole, 1- benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, and 1 -Cyanoethyl-2-phenylimidazolium trimellitate and the like.
Examples of the epoxy resin in the compound obtained by adducting the imidazole compound to the epoxy resin include those exemplified for the curable resin (A).
Examples of commercially available compounds obtained by adducting an imidazole compound to an epoxy resin include EH-5011S (manufactured by ADEKA Corporation) and FXR-1121 (manufactured by T&K TOKA Corporation).

[(b3) A compound obtained by adducting a polyvalent amine compound to at least one compound selected from the group consisting of an epoxy resin, an isocyanate compound, and urea]
(Polyvalent amine compound)
Polyvalent amine compounds are compounds having at least two primary amino groups, and include diamine compounds having two primary amino groups, triamine compounds having three primary amino groups, and the like. .

(Diamine compound having two primary amino groups)
Examples of diamine compounds having two primary amino groups include, but are not limited to, aliphatic diamines, alicyclic diamines, and aromatic diamines. Further, specific examples of diamine compounds having two primary amino groups include polyvalent amine compounds represented by the following formula (5a).

式中、Ｌは、Ｃ_１～Ｃ_１２アルキレン、１つ若しくはそれ以上のＮＨ（イミノ基）若しくはＯ原子（酸素原子）で非連続的に中断されたＣ_２～Ｃ_１２アルキレン（Ｎ原子（窒素原子）に結合するＨ原子（水素原子）は、アミノ基又はＣ_１～Ｃ_１２アルキルアミノ基で置換されていてもよい）、Ｃ_３～Ｃ_１２シクロアルキレン、Ｃ_１～Ｃ_１２アルキレン－Ｃ_３～Ｃ_１２シクロアルキレン、Ｃ_１～Ｃ_１２アルキレン－Ｃ_３～Ｃ_１２シクロアルキレン－Ｃ_１～Ｃ_１２アルキレン、Ｃ_３～Ｃ_１２シクロアルキレン－Ｃ_１～Ｃ_４アルキレン－Ｃ_３～Ｃ_１２シクロアルキレン、Ｃ_６～Ｃ_１４アリーレン、Ｃ_１～Ｃ_４アルキレン－Ｃ_６～Ｃ_１４アリーレン、Ｃ_１～Ｃ_４アルキレン－Ｃ_６～Ｃ_１４アリーレン－Ｃ_１～Ｃ_４アルキレン、又はＣ_６～Ｃ_１４アリーレン－Ｃ_１～Ｃ_４アルキレン－Ｃ_６～Ｃ_１４アリーレン（ここで、アルキレンは、直鎖又は分岐鎖であり、ハロゲンで置換されていてもよく、Ｃ_３～Ｃ_１２シクロアルキレン又はＣ_６～Ｃ_１４アリーレンは、非置換であるか、又はハロゲン若しくはＣ_１～Ｃ_４アルキルで置換されていてもよい。）である。

In the formula, L is C ₁ -C ₁₂ alkylene, C ₂ -C ₁₂ alkylene (N atom (nitrogen atom) may be substituted with an amino group or a C ₁ -C ₁₂ alkylamino group), C ₃ -C ₁₂ cycloalkylene, C ₁ -C ₁₂ alkylene-C ₃ -C ₁₂ cycloalkylene, C ₁ -C ₁₂ alkylene-C ₃ -C ₁₂ cycloalkylene-C ₁ -C ₁₂ alkylene, C ₃ -C ₁₂ cycloalkylene-C ₁ -C ₄ alkylene-C ₃ -C ₁₂ cycloalkylene , C ₆ -C ₁₄ arylene, C ₁ -C ₄ alkylene-C ₆ -C ₁₄ arylene, C ₁ -C ₄ alkylene-C ₆ -C ₁₄ arylene-C ₁ -C ₄ alkylene, or C ₆ -C ₁₄ arylene —C ₁ -C ₄ alkylene-C ₆ -C ₁₄ arylene (wherein alkylene is linear or branched, optionally substituted with halogen, C ₃ -C ₁₂ cycloalkylene or C ₆ -C ₁₄ Arylene is unsubstituted or optionally substituted with halogen or C ₁ -C ₄ alkyl.).

Among aliphatic diamines, specific examples of compounds in which L is C ₁ to C ₁₂ alkylene in formula (5a) include ethylenediamine, propylenediamine, 1,2-diaminopropane, and 1,3-diaminopropane. , 1,3-diaminobutane, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, dodecamethylenediamine, propane-1,2-diamine, 1,2-diamino-2-methylpropane etc.

Among aliphatic diamines, in formula (5a), compounds wherein L is linear or branched C ₂ -C ₁₂ alkylene interrupted discontinuously by one or more O atoms (oxygen atoms) Specifically, for example, 2,2′-oxybis(ethylamine), 1,2-bis(2-aminoethoxy)ethane, 1,11-diamino-3,6,9-trioxaundecane, bis( 3-aminopropyl) ether, 1,4-butanediol bis(3-aminopropyl) ether, diethylene glycol bis(3-aminopropyl) ether, ethylene glycol bis(3-aminopropyl) ether and the like.

Among aliphatic diamines, in formula (5a), L is a linear or branched C ₂ -C ₁₂ alkylene (N atom ( The H atom (hydrogen atom) bonded to the nitrogen atom) may be substituted with an amino group or a C ₁ to C ₁₂ alkylamino group), specifically, for example, diethylenetriamine, triethylene Tetramine, tetraethylenepentamine, pentaethylenehexamine, tris(2-aminoethyl)amine, N,N'-bis(3-aminopropyl)ethylenediamine, bis(hexamethylene)triamine, 3,3'-diamino-N- methyldipropylamine, 3,3'-diaminodipropylamine, bis(3-aminopropyl)methylamine and the like.

Specific examples of alicyclic diamines include isophoronediamine, 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, trans-1,2-diaminocyclohexane, 1,3-bis(aminomethyl)cyclohexane, 4,4′-methylenebis(cyclohexylamine) 1,4-diamino-3,6-diethylcyclohexane, isophoronediamine and the like.

Specific examples of aromatic diamines include p-phenylenediamine, m-phenylenediamine, o-xylylenediamine, p-xylylenediamine, m-xylylenediamine, 4,4′-diaminodiphenylmethane, 1, 5-diaminonaphthalene, 1,8-diaminonaphthalene, 2,6-diaminotoluene, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4- Diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl 4'-methylimidazolyl-(1')]-ethyl -s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, an imidazolyl group in which the nitrogen atom at the 1-position is substituted, such as an isocyanuric acid adduct; primary diamines, diaminodiphenylsulfones, etc. having

Specific examples of triamine compounds having three primary amino groups include tris(4-aminophenyl)amine, tris(3-aminopropyl)amine, tris(2-aminoethyl ) polyalkylpolyamines such as amines, diethylenetriamine, triethylenetriamine, tetraethylenetriamine and tetraethylenepentamine.

The polyvalent amine compound in (b3) does not include hydrazine (NH ₂ NH ₂ ), hydrazide compounds, and (b1) carbazide compounds. The polyvalent amine compound in (b3) preferably does not contain a compound having a hydrazino group (NH ₂ NH--). Here, the hydrazide compound includes those exemplified in the hydrazide compounds described later. Polyvalent amine compounds other than (b3) include hydrazine, hydrazide compounds, and (b1) carbazide compounds. However, polyvalent amine compounds other than (b3) may not contain hydrazine, hydrazide compounds, and (b1) carbazide compounds.

(Epoxy resin)
Examples of the epoxy resin in the compound obtained by adducting the polyvalent amine compound to the epoxy resin include those exemplified for the curable resin (A).

(isocyanate compound)
Examples of the isocyanate compound in the compound obtained by adducting the polyvalent amine compound to the isocyanate compound include those exemplified in the isocyanate compound (C) described below.

Commercially available products of adducts of polyvalent amine compounds and epoxy resins include EH-5001P, EH-4370S, EH-5015S, EH-4375S, EH-5030S, EH-5057P, and EH-4358S (ADEKA Corporation ), FXR-1020, FXR-1030, and FXR-1081 (manufactured by T&K TOKA Co., Ltd.).

(preferred embodiment)
The (b3) polyvalent amine compound is selected from the group consisting of epoxy resins, isocyanate compounds, and urea, from the viewpoint that the reactivity with the curable resin (A) is further increased and the curing time can be further shortened. As the compound to which at least one compound is adducted, a compound obtained by adducting a polyvalent amine compound to an isocyanate compound is preferable.

[(b4) a mixed crystal of two or more hydrazide compounds, (b5) a mixed crystal of one or more mono- or polyvalent amine compounds and one or more hydrazide compounds, and (b6) one or more imidazole compounds and 1 Mixed Crystal with More Than Seed Hydrazide Compounds]
Mixed crystals of two or more hydrazide compounds, mixed crystals of one or more mono- or polyvalent amine compounds and one or more hydrazide compounds, and mixed crystals of one or more imidazole compounds and one or more hydrazide compounds are , is a mixed crystal having a crystal system different from the crystal system of a single component contained in the mixed crystal. Confirming the presence of peaks other than those originating from the raw materials by comparing the X-ray diffraction spectrum of the mixed crystal with the X-ray diffraction spectrum of one type of mono- or polyvalent amine compound as raw materials contained in the mixed crystal. can infer the existence of mixed crystals.
Examples of hydrazide compounds in these mixed crystals include those exemplified in the hydrazide compounds described below.
(b5) As polyvalent amine compounds in mixed crystals of one or more mono- or polyvalent amine compounds and one or more hydrazide compounds, (b3) polyvalent amine compounds are composed of an epoxy resin, an isocyanate compound, and urea. Compounds adducted to at least one compound selected from the group include those exemplified.
(b6) Examples of the imidazole compound in the mixed crystal of one or more imidazole compounds and one or more hydrazide compounds include those exemplified in (b2) Compounds in which imidazole is adducted to epoxy resin.

(Hydrazide compound)
The hydrazide compounds include monobasic hydrazide having one hydrazide group in the molecule, dibasic hydrazide having two hydrazide groups in the molecule, tribasic hydrazide having three hydrazide groups in the molecule, Examples include polyfunctional hydrazides having four or more hydrazide groups in the molecule.

Specific examples of monobasic hydrazides include acetohydrazide, propionic hydrazide, pentanoic hydrazide, lauric hydrazide, cyclohexanecarbohydrazide, salicylic hydrazide, p-hydroxybenzoic hydrazide, naphthoic hydrazide, and benzenesulfonohydrazide. be done.

Specific examples of dibasic acid hydrazides include oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, adipic acid dihydrazide, pimelic acid dihydrazide, suberic acid dihydrazide, azelaic acid dihydrazide, sebacic acid dihydrazide, dodecanoic acid dihydrazide, hexadecane dihydrazide acid dihydrazide, isophthalic acid dihydrazide, terephthalic acid dihydrazide, carbohydrazide, maleic acid dihydrazide, fumaric acid dihydrazide, diglycolic acid dihydrazide, tartaric acid dihydrazide, malic acid dihydrazide, 2,6-naphthoic acid dihydrazide, 1,4-naphthoic acid dihydrazide, 4,4′-bisbenzene dihydrazide, hydroquinone diglycolic acid dihydrazide, resorcinol diglycolic acid dihydrazide, catechol diglycolic acid dihydrazide, 4,4′-ethylidenebisphenol-diglycolic acid dihydrazide, 4,4′-vinylidenebisphenol-diglycol and acid dihydrazides.

Tribasic acid hydrazides include, for example, 1,3,5-tris(2-hydrazinocarbonylalkyl)isocyanurates such as 1,3,5-tris(2-hydrazinocarbonylethyl)isocyanurates.
Examples of polyfunctional hydrazides include polyacrylic acid hydrazides.

Further, when the hydrazide compound is a combination of two or more hydrazide compounds, at least one of the hydrazide compounds is preferably a dibasic dihydrazide, and more preferably all hydrazide compounds are dibasic dihydrazides. . Combinations of hydrazide compounds, where all hydrazide compounds are dibasic acid dihydrazides, include, for example, adipic acid dihydrazide and sebacic acid dihydrazide, adipic acid dihydrazide and decanedioic acid dihydrazide, sebacic acid dihydrazide and decanedioic acid dihydrazide, sebacic acid dihydrazide and dodecanedioic acid dihydrazide, etc., and a combination of sebacic acid dihydrazide and dodecanedioic acid dihydrazide is more preferable.

A mixed crystal of two or more kinds of hydrazide compounds has about 2 to 3 strong diffraction peaks at a Bragg angle (2θ±0.2°) of 20 to 25° in the X-ray diffraction spectrum by CuKα rays. It has crystal modifications. Also, the hydrazide compound used for the mixed crystal is preferably a crystalline hydrazide compound. Here, the crystalline hydrazide compound has a peak in the range of the Bragg angle 2θ (error 2θ±0.2°) of 5.0 to 7.5° in the X-ray diffraction spectrum for CuKα rays (wavelength 1.541 Å). A hydrazide compound having

(Composition of mixed crystal, etc.)
The ratio of the mono- or polyvalent amine compound, imidazole compound and/or hydrazide compound used in the mixed crystal depends on various conditions such as the type of epoxy resin to be cured, its application, and the required curing time and curing temperature. can be determined as appropriate. For example, two or more compounds are used in combination so that the total mixed crystal content of one compound is generally 1 to 99% by weight, preferably 10 to 90% by weight, more preferably 30 to 70% by weight. is good.

(Additional components contained in mixed crystals)
The mixed crystal can further contain a metal element capable of forming a complex with the compound contained in the mixed crystal. A mixed crystal containing a metal element is preferable because it can further improve the effect of improving liquid stability. Preferably, a mixed crystal of two or more hydrazide compounds containing a mixed crystal of two or more hydrazide compounds and a metal element capable of forming a complex with the hydrazide compound contained in the mixed crystal of two or more hydrazide compounds. be.

Metal elements preferably include aluminum, titanium, tin, zirconium, zinc, iron, magnesium, cobalt, nickel, bismuth, molybdenum, copper, antimony, barium, boron, manganese, indium, cesium, holmium, yttrium, silicon, and calcium. , silver, germanium, and gold. More preferably, the metal element includes at least one selected from the group consisting of aluminum, titanium, tin, zirconium, zinc, iron, magnesium, cobalt, nickel, bismuth, molybdenum, copper, antimony, barium and boron. . The metal elements can be used singly or in any combination of two or more. In addition, metal elements in the form of metal oxides and metal hydroxides can be used.

The content of the metal element is preferably 0.1 to 20.0% by mass, more preferably 1.0 to 10.0% by mass, based on the total amount of the mixed crystal and the metal element. When the content of the metal element is 0.1 to 20.0% by mass with respect to the total of the compound and the metal element contained in the mixed crystal, the metal element and the compound contained in the mixed crystal, such as crystalline hydrazide It is assumed that the compounds form good complexes.

(Method for producing mixed crystal)
A method for producing a mixed crystal comprises two or more amine compounds (i.e., a combination of two or more hydrazide compounds, a combination of one or more mono- or polyvalent amine compounds and one or more hydrazide compounds, or , a combination of one or more imidazole compounds and one or more hydrazide compounds) are heated to a melting point or higher and mixed to obtain a mixture, and the steps of cooling and solidifying the mixture. Specifically, the method for producing a mixed crystal includes (b4′) a combination of two or more hydrazide compounds, (b5′) one or more mono- or polyvalent amine compounds (one or more primary a combination of a primary mono-, di- and polyamine compound having an amino group, a secondary mono-, di- and polyamine compound having one or more secondary amino groups in the molecule) and one or more hydrazide compounds; (b6′) a combination of one or more imidazole compounds and one or more hydrazide compounds; , obtaining a mixture, and cooling and solidifying the mixture.

In the step of heating, melting and mixing, the temperature at which the two or more amine compounds as raw materials are heated is not particularly limited, but is a temperature at which the mixture of the two or more amine compounds as raw materials becomes substantially liquid. is preferred. The temperature at which the two or more amine compounds as raw materials become substantially liquid is a temperature near the melting point of the two or more amine compounds as raw materials, for example, a temperature about 10° C. lower than the melting point to 10° C. lower than the melting point. It is preferable that the temperature is as high as about °C. Here, the melting point of the two or more amine compounds as raw materials refers to the temperature of the highest melting point among the melting points of the two or more amine compounds as raw materials.

The cooling rate in the step of cooling and solidifying a molten mixture of two or more amine compounds as raw materials is preferably 20 to 0.01° C./min, more preferably 10 to 0.05° C./min, and still more preferably 5 to 0.1°C/min. Cooling may be performed in multiple stages, for example, in two stages. For example, it is possible to cool to 100 to 50° C. in the first stage, grow crystals at that temperature, and cool to room temperature in the second stage.

In addition, a method for producing a mixed crystal containing a mixed crystal of two or more kinds of amine compounds as raw materials and a metal capable of forming a complex with the amine compound as raw materials is a mono- or polyvalent amine compound, an imidazole compound, or a hydrazide. A step of heat-melting and mixing the compound with a metal element capable of forming a complex with the mono- or polyvalent amine compound, imidazole compound, or hydrazide compound to obtain a mixture, subjecting the mixture to constant temperature treatment, and cooling the mixture. and obtaining a solidified body.

The step of heating, melting and mixing to obtain a mixture and the step of cooling the mixture to obtain a solidified body are as described above.
The step of isothermally treating the mixture is a step of isothermally treating the mixture at a constant temperature for a certain period of time. Isothermal treatment means that the mixture is kept at a constant temperature (error range ±10°C) for a constant period of time. The temperature for isothermal treatment is not particularly limited, but is preferably 100 to 280°C, more preferably 130 to 250°C. The time for constant temperature treatment is not particularly limited, but it can be an optimum treatment time, for example, 0.01 to 10 hours, depending on the purpose of use when used as a curing agent.

Furthermore, the method for producing mixed crystals preferably includes a step of pulverizing the solidified product obtained by cooling into particles having an average particle size of 0.1 to 20.0 μm.
As a method for pulverizing, it is preferable to pulverize the solidified body using, for example, a high-pressure pulverizer. Examples of the high-pressure pulverizer include a cross jet mill (manufactured by Kurimoto Tekkosho Co., Ltd.), a counter jet mill (manufactured by Hosokawa Micron Co., Ltd.), and a nano jetmizer (manufactured by Aisin Nano Technologies Co., Ltd.).

(Preferred embodiment of latent curing agent (B))
The latent hardener (B) preferably has a granular form. Although the average particle size of the latent curing agent (B) is not particularly limited, it is preferably 0.1 to 20.0 μm, more preferably 0.2 to 10.0 μm. The average particle size can be determined by a particle size distribution analyzer using a laser diffraction/scattering method, and the average particle size is the volume average value D ₅₀ (D ₅₀ is the cumulative volume It is the value measured as the particle diameter at 50%, that is, the median diameter. The latent curing agent (B) having a granular form can be obtained by pulverizing the latent curing agent (B).

3. Isocyanate compound (C)
The isocyanate compound is a compound having at least one isocyanate group (-N=C=O) and is not particularly limited. be done.

式（１ａ）において、Ｘ^４は、Ｃ_１～Ｃ_１２アルキル、１つ若しくはそれ以上のＯ原子（酸素原子）で非連続的に中断されたＣ_２～Ｃ_１２アルキル、Ｃ_１～Ｃ_１２アルキルオキシカルボニルアルキレン、Ｃ_３～Ｃ_１２シクロアルキル、Ｃ_１～Ｃ_１２アルキル－Ｃ_３～Ｃ_１２シクロアルキレン、Ｃ_３～Ｃ_１２シクロアルキル－Ｃ_１～Ｃ_１２アルキレン－Ｃ_３～Ｃ_１２シクロアルキレン、Ｃ_６～Ｃ_１４アリール、Ｃ_１～Ｃ_４アルキル－Ｃ_６～Ｃ_１４アリーレン、Ｃ_６～Ｃ_１４アリール－Ｃ_１～Ｃ_４アルキレン－Ｃ_６～Ｃ_１４アリーレン（ここで、アルキレンは、直鎖又は分岐鎖であり、ハロゲンで置換されていてもよく、Ｃ_３～Ｃ_１２シクロアルキル、Ｃ_３～Ｃ_１２シクロアルキレン、Ｃ_６～Ｃ_１４アリール、又はＣ_６～Ｃ_１４アリーレンは、非置換であるか、又はハロゲン若しくはＣ_１～Ｃ_４アルキルで置換されている）、又は（メタ）アクリロイルオキシアルキルである。 (Monoisocyanate compound)
Examples of monoisocyanate compounds include compounds represented by the following formula (1a).

In formula (1a), X ⁴ is C ₁ -C ₁₂ alkyl, C ₂ -C ₁₂ alkyl discontinuously interrupted by one or more O atoms (oxygen atoms), C ₁ -C ₁₂ alkyl oxycarbonylalkylene, C ₃ -C ₁₂ cycloalkyl, _{C 1} -C ₁₂ alkyl-C ₃ -C ₁₂ cycloalkylene, C ₃ -C ₁₂ cycloalkyl-C 1 -C ₁₂ alkylene-C ₃ -C ₁₂ cycloalkylene, C ₆ -C ₁₄ aryl, C ₁ -C ₄ alkyl-C ₆ -C ₁₄ arylene, C ₆ -C ₁₄ aryl-C ₁ -C ₄ alkylene-C ₆ -C ₁₄ arylene (where alkylene is a linear or branched and optionally substituted with halogen, C ₃ -C ₁₂ cycloalkyl, C ₃ -C ₁₂ cycloalkylene, C ₆ -C ₁₄ aryl, or C ₆ -C ₁₄ arylene is unsubstituted or substituted with halogen or C ₁ -C ₄ alkyl), or (meth)acryloyloxyalkyl.

式（１ｂ）において、Ｒ^６は水素原子又はメチル基を示し、Ｒ^７はＣ_１～Ｃ_６アルキレンを示す。Ｒ^７のＣ_１～Ｃ_６アルキレンの炭素数の範囲は、好ましくはＣ_２～Ｃ_６、より好ましくはＣ_３～Ｃ_６である。 (Meth)acryloyloxyalkyl isocyanate as a monoisocyanate compound includes compounds represented by the following formula (1b).

In formula (1b), R ⁶ represents a hydrogen atom or a methyl group, and R ⁷ represents C ₁ -C ₆ alkylene. The carbon number range of C ₁ -C ₆ alkylene of R ⁷ is preferably C ₂ -C ₆ , more preferably C ₃ -C ₆ .

Specific examples of monoisocyanate compounds include methyl isocyanate, ethyl isocyanate, n-hexyl isocyanate, cyclohexyl isocyanate, 2-ethylhexyl isocyanate, phenyl isocyanate, benzyl isocyanate, propyl isocyanate, isopropyl isocyanate, butyl isocyanate, heptyl isocyanate, dodecyl isocyanate, octadecyl isocyanate, t-butyl isocyanate, ethyl isocyanate acetate, butyl isocyanate acetate, (S)-(-)-2-isocyanato methyl propionate, phenyl isocyanate, 1-naphthyl isocyanate, 4-chlorophenyl isocyanate, isocyanate Acid 4-fluorophenyl, phenethyl isocyanate, p-tolyl isocyanate, m-tolyl isocyanate, 3,5-dimethylphenyl isocyanate, 3-(triethoxysilyl)propyl isocyanate and the like.

Specific examples of the (meth)acryloyloxyalkyl isocyanate include (meth)acryloyloxymethyl isocyanate, (meth)acryloyloxyethyl isocyanate, and (meth)acryloyloxypropyl isocyanate.

式（２ａ）において、Ｘ^５は、Ｃ_１～Ｃ_１２アルキレン、１つ若しくはそれ以上のＯ原子（酸素原子）で非連続的に中断されたＣ_２～Ｃ_１２アルキレン、Ｃ_１～Ｃ_１２アルキレンオキシカルボニルアルキレン、Ｃ_３～Ｃ_１２シクロアルキレン、Ｃ_１～Ｃ_１２アルキレン－Ｃ_３～Ｃ_１２シクロアルキレン、Ｃ_１～Ｃ_１２アルキレン－Ｃ_３～Ｃ_１２シクロアルキレン－Ｃ_１～Ｃ_１２アルキレン、Ｃ_３～Ｃ_１２シクロアルキレン－Ｃ_１～Ｃ_１２アルキレン－Ｃ_３～Ｃ_１２シクロアルキレン、ジＣ_３～Ｃ_１２シクロアルカンジイル、Ｃ_６～Ｃ_１４アリーレン、Ｃ_１～Ｃ_４アルキレン－Ｃ_６～Ｃ_１４アリーレン－Ｃ_１～Ｃ_４アルキレン、又はＣ_６～Ｃ_１４アリーレン－Ｃ_１～Ｃ_４アルキレン－Ｃ_６～Ｃ_１４アリーレン（ここで、アルキレンは、直鎖又は分岐鎖であり、ハロゲンで置換されていてもよく、Ｃ_３～Ｃ_１２シクロアルキレン又はＣ_６～Ｃ_１４アリーレンは、非置換であるか、又はハロゲン若しくはＣ_１～Ｃ_４アルキルで置換されている）である。 (Diisocyanate compound)
Diisocyanate compounds include compounds represented by the following formula (2a).

In formula (2a), X ⁵ is C ₁ -C ₁₂ alkylene, C ₂ -C ₁₂ alkylene interrupted discontinuously by one or more O atoms (oxygen atoms), C ₁ -C ₁₂ alkylene oxycarbonylalkylene, C ₃ -C ₁₂ cycloalkylene, C ₁ -C ₁₂ alkylene-C ₃ -C ₁₂ cycloalkylene, C ₁ -C ₁₂ alkylene-C ₃ -C ₁₂ cycloalkylene-C ₁ -C ₁₂ alkylene, C ₃ -C ₁₂ cycloalkylene-C ₁ -C ₁₂ alkylene-C ₃ -C ₁₂ cycloalkylene, di-C ₃ -C ₁₂ cycloalkanediyl, C ₆ -C ₁₄ arylene, C ₁ -C ₄ alkylene-C ₆ -C ₁₄ arylene-C ₁ -C ₄ alkylene, or C ₆ -C ₁₄ arylene-C ₁ -C ₄ alkylene-C ₆ -C ₁₄ arylene, wherein alkylene is linear or branched and substituted with halogen. C ₃ -C ₁₂ cycloalkylene or C ₆ -C ₁₄ arylene is unsubstituted or substituted with halogen or C ₁ -C ₄ alkyl).

Specific examples of diisocyanate compounds include diphenylmethane diisocyanate (MDI), tolylene diisocyanate (TDI), xylene diisocyanate (XDI), hydrogenated xylene diisocyanate (hydrogenated XDI), isophorone diisocyanate (IPDI), and tolidine diisocyanate (TPDI). ), hexamethylene diisocyanate (HDI), dicyclohexylmethane diisocyanate (HMDI), 2,4,4-trimethylhexamethylene diisocyanate (TMHDI), 3,5,5-trimethylhexamethylene diisocyanate (TMHDI), 4,4′-diisocyanate 3,3'-dimethylbiphenyl, 4,4'-diisocyanate 3,3'-dimethyldiphenylmethane, 2,2-bis(4-isocyanatophenyl)hexafluoropropane, 2,4-diisocyanatotoluene, 1,3-bis( 2-isocyanate, 2-propyl)benzene, tolylene-2,6-diisocyanate, 1,4-phenylene diisocyanate, 1,3-phenylene diisocyanate, 1,5-diisocyanatonaphthalene and the like.

式中、Ｒ^２は、同一又は異なり、直鎖又は分岐鎖のＣ_１～Ｃ_１２アルキレンである。 (triisocyanate compound)
Examples of the triisocyanate compound include compounds having an isocyanate group at three terminals and having an isocyanurate structure, a biuret structure or an adduct structure. Triisocyanate compounds having an isocyanurate structure include compounds having an isocyanurate structure represented by the following formula (3a).

wherein R ² is the same or different and is a linear or branched C ₁ -C ₁₂ alkylene.

式中、Ｒ^３は、同一又は異なり、直鎖又は分岐鎖のＣ_１～Ｃ_１２アルキレンである。 Examples of triisocyanate compounds having a biuret structure include compounds represented by the following formula (3b).

wherein R ³ are the same or different and are linear or branched C ₁ -C ₁₂ alkylene.

式中、Ｒ^４は、同一又は異なり、直鎖又は分岐鎖のＣ_１～Ｃ_１２アルキレンであり、Ｒ^５は、ＣＨである。 Triisocyanate compounds having an adduct structure include compounds represented by the following formula (3c).

wherein R ⁴ is the same or different, linear or branched C ₁ -C ₁₂ alkylene, and R ⁵ is CH.

Specific examples of triisocyanate compounds include tri(isocyanatomethyl)isocyanurate, tri(isocyanatoethyl)isocyanurate, tri(isocyanatopropyl)isocyanurate, tri(isocyanatobutyl)isocyanurate, and tri(isocyanatohexyl)isocyanate. nurate, N,N'-2-tris-isocyanatomethylmalonic acid amide, N,N'-2-tris-isocyanatohexylmalonic acid amide and the like.

式中、Ｘ^３は、Ｃ_３～Ｃ_１２シクロアルキル－Ｃ_１～Ｃ_１２アルキレン－Ｃ_３～Ｃ_１２シクロアルキル、又はＣ_６～Ｃ_１４アリール－Ｃ_１～Ｃ_４アルキレン－Ｃ_６～Ｃ_１４アリール（アルキレンは、直鎖又は分岐鎖であり、ハロゲンで置換されていてもよく、Ｃ_３～Ｃ_１２シクロアルキル又はＣ_６～Ｃ_１４アリールは、非置換であるか、又はハロゲン若しくはＣ_１～Ｃ_４アルキルで置換されていてもよい）から誘導される４価の基である。 (tetraisocyanate compound)
Examples of the tetraisocyanate compound include compounds represented by the following formula (4a).

wherein X ³ is C ₃ -C ₁₂ cycloalkyl-C ₁ -C ₁₂ alkylene-C ₃ -C ₁₂ cycloalkyl, or C ₆ -C ₁₄ aryl-C ₁ -C ₄ alkylene-C ₆ -C ₁₄ Aryl (alkylene is straight or branched and may be substituted with halogen, C ₃ -C ₁₂ cycloalkyl or C ₆ -C ₁₄ aryl is unsubstituted or substituted with halogen or C ₁ - optionally substituted with _C4 alkyl).

Further, examples of the tetraisocyanate compound include tetraisocyanate silane represented by the following formula (4b).

Specific examples of tetraisocyanate compounds include 4,4'-diphenylmethane-2,2',5,5'-tetraisocyanate and tetraisocyanatesilane.

4. Production method A method for producing a curable resin composition is a method for producing a curable resin composition containing a curable resin (A), a latent curing agent (B) and an isocyanate compound (C),
A step of mixing the curable resin (A), the latent curing agent (B), the isocyanate compound (C) and optional components without pre-reacting the latent curing agent (B) and the isocyanate compound (C).
The mixing method may be stirring and mixing the curable resin (A) and the isocyanate compound (C), and then stirring and mixing the latent curing agent (B), the curable resin (A) and the latent curing agent ( After B) is mixed with stirring, the isocyanate compound (C) may be mixed with stirring.
When the temperature during mixing is the temperature near the melting point of the latent curing agent (B) to be mixed, or the temperature in the reaction activation temperature zone, the curable resin (A) and the latent curing agent (B) is not preferable because it reacts with Also, if the temperature during mixing is too low, the fluidity of the resin is suppressed, making it difficult to stir. Therefore, the temperature during mixing is preferably 0 to 40°C, more preferably 10 to 40°C, and even more preferably 20 to 40°C.

In a conventional method for producing a curable resin composition, a latent curing agent and an isocyanate compound are pre-reacted, and the surface of the latent curing agent covered with the isocyanate compound is added to the curable resin composition.
However, in the present invention, the curable resin composition can be easily produced only by including the step of mixing the curable resin (A), the latent curing agent (B) and the isocyanate compound (C). The reason for this is that when the curable resin (A), the latent curing agent (B) and the isocyanate compound (C) are mixed, the reactivity between the latent curing agent (B) and the isocyanate compound (C) is high. This is because the reaction between the amino group on the surface of the latent curing agent and the isocyanate compound proceeds in the mixed composition.

5. State of latent curing agent (B) and isocyanate compound (C) As described above, the curable resin composition is a curable resin ( It is produced by mixing A), a latent curing agent (B) and an isocyanate compound (C). After mixing the curable resin (A), the latent curing agent (B) and the isocyanate compound (C) in this way, it has been confirmed that the amount of surface amines on the latent curing agent (B) decreases. . Here, the surface amine amount refers to the amount of amino groups present on the surface or surface layer of the particulate latent curing agent (B). Therefore, part or all of the latent curing agent (B) and part or all of the isocyanate compound (C) are reacting. Preferably, all of the latent curing agent (B) and all of the isocyanate compound (C) are reacted. For example, when all of the latent curing agent (B) has reacted, the latent curing agent (B) is not contained in an unreacted state in the curable resin composition, but the latent curing agent (B ) and the isocyanate compound (C) is confirmed to be the curable resin composition of the present invention.
When part or all of the latent curing agent (B) and part or all of the isocyanate compound (C) are thus reacting, at least part of the surface of the latent curing agent (B) The isocyanate compound (C) is reacting. That is, since the reactivity of the latent curing agent (B) and the isocyanate compound (C) is high, after mixing the latent curing agent (B) and the isocyanate compound (C), the isocyanate compound ( It is believed that C) attaches to the surface of the latent hardener (B). Therefore, in the curable resin composition, the amount of amine on the surface of the latent curing agent (B) decreases over time.

The state in which the latent curing agent (B) and the isocyanate compound (C) are reacting means that the reactive isocyanate group in the isocyanate compound (C) is the primary amino group of the latent curing agent (B), and / Alternatively, it is presumed to be in a state where it reacts with a secondary amino group to form a urea bond, biuret bond, or allophanate bond.

6. Compounding amount The curable resin composition preferably contains 1 to 100 parts by mass, more preferably 2 to 70 parts by mass, of the latent curing agent (B) with respect to 100 parts by mass of the curable resin (A). , more preferably 2 to 50 parts by mass. The curable resin composition preferably contains 0.0002 to 28 parts by mass of the isocyanate compound (C), more preferably 0.002 to 28 parts by mass, based on 100 parts by mass of the curable resin (A). , 0.02 to 28 parts by mass. Such a blending ratio is preferable from the viewpoint of liquid stability and curability of the composition.

In addition, the curable resin composition preferably contains 0.02 to 28 parts by mass of the isocyanate compound (C) with respect to 100 parts by mass of the latent curing agent (B), and contains 0.04 to 28 parts by mass. is more preferred, and 0.05 to 25 parts by mass is even more preferred. Such a blending ratio is preferable from the viewpoint of liquid stability and curability of the composition.

7. Other Components The curable resin composition contains, in addition to the above components, a photopolymerization initiator (D) and, if necessary, an inorganic filler (E), an organic filler (F), and a coupling agent (G). is preferably included.

[Photopolymerization initiator (D)]
Photopolymerization initiators include benzophenone, 2,2-diethoxyacetophenone, benzyl, benzoyl isopropyl ether, benzyl dimethyl ketal, 1-hydroxycyclohexylphenyl ketone, thioxanthone and the like. Moreover, you may use the photoradical polymerization initiator marketed as a photoinitiator. Commercially available photoradical polymerization initiators include, for example, Irgacure 907, Irgacure 819, Irgacure 651, Irgacure 369, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and Lucirin TPO (all of which are manufactured by BASF Japan). ) and the like.

[Inorganic filler (E)]
The inorganic filler is not particularly limited, and examples thereof include spherical silica, spherical alumina, spherical titanium oxide, spherical aluminum oxide, and spherical calcium carbonate. Among them, spherical silica is preferable because it has excellent dispersibility and is excellent in the effect of improving the adhesiveness of the sealant suitable for the liquid crystal dropping method and the moisture resistance of the cured product.

The mixing ratio of each component of the curable resin composition is preferably 0.5 to 10 parts by mass, more preferably 0.5 to 10 parts by mass of the photopolymerization initiator (D) with respect to 100 parts by mass of the curable resin composition. 5 to 7 parts by mass, more preferably 0.8 to 4 parts by mass. Also, (E) the inorganic filler is preferably 0 to 40 parts by mass, more preferably 2 to 30 parts by mass, and still more preferably 3 to 20 parts by mass with respect to 100 parts by mass of the curable resin composition. Further, the content of (D) the photopolymerization initiator is preferably 0.5 to 3% by mass in the total mass of the liquid crystal sealant composition. In addition, (E) the inorganic filler is preferably 0 to 40% by mass in the total mass of the liquid crystal sealant composition.

The curable resin composition is preferably produced by sufficiently kneading with a paint roll or the like, paying particular attention to uniform and complete dispersion of solids such as inorganic fillers.

[Organic filler (F)]
The organic filler is not particularly limited, and examples thereof include fine particles of monomers or polymers, specifically polyester fine particles, vinyl polymer fine particles, acrylic polymer fine particles, and polyurethane fine particles. Among them, an acrylic resin filler is preferable because of its excellent transparency.

[Coupling agent (G)]
The coupling agent is not particularly limited, and examples thereof include silane coupling agents.

[Other ingredients]
The curable resin composition may optionally contain silicone resin, urea resin, imide resin, glass, etc., in addition to the above resins.

In addition, the curable resin composition may optionally contain various additives such as antioxidants, ultraviolet absorbers, light stabilizers, paint surface improvers, thermal polymerization inhibitors, leveling agents, surfactants, Colorants, storage stabilizers, plasticizers, lubricants, inorganic particles, anti-aging agents, wettability improvers, antistatic agents and the like may be added.

[Liquid crystal display panel]
The curable resin composition satisfies the demands for finer lines and diversification of adhesive properties, and exhibits adhesive strength capable of suppressing peeling during cell cutting and mounting of an IC for driving a liquid crystal cell. It can be suitably used for manufacturing liquid crystal display panels. Thus, the curable resin composition is preferably used as a sealant composition for liquid crystal display elements. In addition, the liquid crystal display panel includes a facing glass substrate, a cured product of a curable resin composition that bonds the facing glass substrate, and a liquid crystal sealed with a cured product of the facing glass substrate and the curable resin composition. Prepare.

[Method for manufacturing liquid crystal display panel]
2. Description of the Related Art A liquid crystal dripping method is known as one of methods for manufacturing liquid crystal display elements such as liquid crystal display cells. In the liquid crystal dripping method, for example, a frame of a sealant for a liquid crystal display element is formed on one of the substrates, liquid crystal is dropped into the frame, and then the other substrate is bonded to seal the liquid crystal and display the liquid crystal. A method of manufacturing a device. Recently, a photo-heat combination type curable resin composition is used, and after sandwiching it between two substrates, the curable resin composition is photo-cured by ultraviolet irradiation or the like as the first step, and heat-cured as the second step. method is adopted. In addition, a method of manufacturing a liquid crystal display cell by only photocuring a curable resin composition after dropping a liquid crystal, and a method of manufacturing a liquid crystal display cell by only thermal curing have been studied.
A liquid crystal injection method is also known as one of other manufacturing methods. In the liquid crystal injection method, for example, when forming a sealant frame, a part that will be a liquid crystal injection port is provided, the base materials are bonded together and heat cured, and then the liquid crystal is injected. It is a method of producing a liquid crystal display cell by curing.
The curable resin composition is not limited to the method described above, and is widely and suitably used for manufacturing liquid crystal panels.

[Production Example 1: Production method of 1,1′-(hexane-1,6-diyl)bis[3-(2-aminoethyl)urea (adduct product (Product 1) of polyvalent amine and isocyanate compound)]

Solution A was prepared by dissolving 17.17 g of hexamethylene diisocyanate in 118 g of ethanol, and solution B was prepared by dissolving 61.36 g of ethylenediamine in 150 g of ethanol. Solution A was added dropwise at a rate of 1.4 g/min while solution B was stirred at 25° C. in a three-necked flask. After the dropwise addition of the dissolution liquid A was completed, the reaction liquid was measured with a Fourier transform infrared spectrophotometer, and it was confirmed that there was no peak around 2250 cm ⁻¹ derived from the isocyanate group, and the reaction was terminated. 1 mol of hexamethylene diisocyanate was reacted with 10 mol of ethylenediamine (molar ratio: 1:10).
After completion of the reaction, filter paper (No. 4, manufactured by Kiriyama Co., Ltd.) is filtered through a Kiriyama funnel (manufactured by Kiriyama Co., Ltd.), deliquoring is performed, and the resulting filtered material is washed with 100 ml of ethanol, and further filtered. The filtered material obtained was dried in a vacuum oven at 50°C. After drying, it is naturally cooled to room temperature, pulverized with a high-pressure pulverizer (trade name: Nano Jetmizer, manufactured by Aisin Nanotechnologies Co., Ltd.), and the average particle size (median diameter) is 2.2 μm. and an isocyanate compound (hereinafter also referred to as "Product 1").

[Production Example 2: Production method of adduct (Product 2) of polyvalent amine and urea]
750 g (5.5 mol) of m-xylylenediamine and 50 g (0.832 mol) of urea were placed in a 1 L eggplant flask and stirred at 175° C. for 5.5 hours. It was then cooled to room temperature. 500 ml of THF (tetrahydrofuran) was added, stirred and filtered. The filtrate was washed with 600 ml of THF while stirring, and filtered again. Here, 2000 g of toluene was added to the obtained filtrate, and the precipitated crystals were filtered. The filtered product was vacuum-dried at 50° C. and pulverized with a high-pressure pulverizer (trade name: Nano Jetmizer, manufactured by Aisin Nano Technologies Co., Ltd.) to obtain a polyvalent amine having an average particle diameter (median diameter) of 2.0 μm. and urea adduct (hereinafter also referred to as "product 2").

[Production Example 3: Method for producing 4,4′-hexamethylenebis(semicarbazide) (product 3)]

A solution A in which 16.8 g of hexamethylene diisocyanate was dissolved in 150 g of ethanol and a solution B in which 10 g of hydrazine was dissolved in 150 g of ethanol were prepared. Solution A was added dropwise at a rate of 1.4 g/min while solution B was being stirred at a controlled temperature of 25°C. After the dropwise addition of the dissolution liquid A was completed, the reaction liquid was measured with a Fourier transform infrared spectrophotometer, and it was confirmed that there was no peak around 2250 cm ⁻¹ derived from the isocyanate group, and the reaction was terminated. 2 mol of hydrazine was reacted with 1 mol of hexamethylene diisocyanate (molar ratio: 1:2).
After completion of the reaction, filter paper (No. 4, manufactured by Kiriyama Co., Ltd.) is filtered through a Kiriyama funnel (manufactured by Kiriyama Co., Ltd.), deliquoring is performed, and the filtered product is washed with 50 ml of ethanol, and further filtered. The filtered material obtained was dried in a vacuum oven at 50°C. After drying, it is pulverized with a high-pressure pulverizer (trade name: Nano Jetmizer, manufactured by Aisin Nano Technologies Co., Ltd.) to obtain a carbazide compound represented by the above chemical formula (B-2) having an average particle size (median diameter) of 2.1 μm (hereinafter referred to as , also referred to as “product 3”).

[Production Example 4: Method for producing a mixed crystal of two or more hydrazide compounds (Product 4)]
Sebacic acid dihydrazide (SDH, manufactured by Otsuka Chemical Co., Ltd.) 500 parts by mass, dodecanedioic acid dihydrazide (DDH, manufactured by Otsuka Chemical Co., Ltd.) 500 parts by mass, and aluminum oxide (AEROXIDE AluC, manufactured by Nippon Aerosil Co., Ltd.) 50 parts by mass (aluminum content of 2.5% by mass) was placed in a separable flask of 5000 ml and heated at 200° C. to obtain a mixture in which two kinds of crystalline hydrazide compounds were dissolved in a substantially liquid state. This mixture was thermostated at 200° C. for 2 hours.
The mixture was then transferred to a Pyrex (registered trademark) glass tray preheated to 200°C and set in a 200°C oven. Then, the molten mixture was cooled to room temperature in an oven at a cooling rate of about 1.0° C./min to obtain a solidified body. The solidified material that has been completely cooled to room temperature is coarsely pulverized with a cutter mill (manufactured by Orient), and finally pulverized with a high-pressure pulverizer (trade name: Nano Jetmizer, manufactured by Aisin Nano Technologies) to obtain an average particle size (median A hydrazide compound with a diameter of 2.5 μm (hereinafter also referred to as “Product 4”) was produced.

[Example 1]
100 parts by mass of partially methacrylated bisphenol A type epoxy resin (PR-850CRP, manufactured by KSM), 10 parts by mass of silica filler (Seahoster KE-C050HG, manufactured by Nippon Shokubai Co., Ltd.) as an inorganic filler, and an acrylic resin as an organic filler. Filler (manufactured by Aica Kogyo Co., Ltd., F-351) 10 parts by mass, a photoradical initiator (manufactured by KSM, EY Resin KR-2) 2 parts by weight and a radical polymerization inhibitor (manufactured by Tokyo Chemical Industry Co., Ltd., BHT: dibutyl hydroxy Toluene) 0.15 parts by mass, 1.0 parts by mass of a silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-403), and 15 parts by mass of Product 1 obtained in Production Example 1 as a latent curing agent. , and 0.1 part by mass of hexamethylene diisocyanate as an isocyanate compound, and uniformly dispersed at room temperature (25° C.) with a three-one motor (manufactured by IKA, trade name: RW28basic) to obtain a curable resin composition.

[Examples 2 to 41 and Comparative Examples 1 to 14]
A curable resin composition was obtained in the same manner as in Example 1, except that the formulation of the curable resin composition was as shown in Tables 1 to 5.
Abbreviations in the table are as follows.
PR-850CRP: partially methacrylated bisphenol A type epoxy resin (manufactured by KSM, product name PR-850CRP)
850S: Bisphenol A type epoxy resin (manufactured by DIC, product name Epiclon 850S)
KE-C050HG: silica filler (manufactured by Nippon Shokubai Co., Ltd., product name Seahoster KE-C050HG)
F-351: acrylic resin filler (manufactured by Aica Kogyo Co., Ltd., product name F-351)
KR-2: Photoradical initiator (manufactured by KSM, product name EY Resin KR-2)
BHT: radical polymerization inhibitor dibutyl hydroxytoluene (manufactured by Tokyo Chemical Industry Co., Ltd., product name BHT)
KBM-403: Silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., product name KBM-403)
TPA-100: polyisocyanate of hexamethylene diisocyanate (manufactured by Asahi Kasei Corporation, product name TPA-100)
E402-100: polyisocyanate of hexamethylene diisocyanate (manufactured by Asahi Kasei, product name E402-100)
TSE-100: Polyisocyanate of hexamethylene diisocyanate (manufactured by Asahi Kasei Corporation, product name TSE-100)
Karenz AOI: 2-isocyanatoethyl acrylate (manufactured by Showa Denko K.K., product name Karenz AOI)
EH-5057P: adduct of polyvalent amine and epoxy resin (manufactured by ADEKA Co., Ltd., product name EH-5057P)
EH-5030S: Adduct product of polyvalent amine and epoxy resin (manufactured by ADEKA Co., Ltd., product name EH-5030S)
FXR-1020: Adduct product of polyvalent amine and epoxy resin (manufactured by T&K TOKA Co., Ltd., product name FXR-1020)
EH-5011S: Adduct product of imidazole and epoxy resin (manufactured by ADEKA Co., Ltd., product name EH-5011S)
EH-4070S: adduct of polyvalent amine and epoxy resin (manufactured by ADEKA Corporation, product name EH-4070S)
ADH: adipic hydrazide (manufactured by Otsuka Chemical Co., Ltd.)

[evaluation]
(Room temperature storage stability)
The viscosities of the resin compositions of Examples and Comparative Examples were measured immediately after preparation (within 2 hours) and taken as initial viscosities. Furthermore, the resin compositions of Examples and Comparative Examples were measured for viscosity after being left at 25°C for 7 days and viscosity after being left at 25°C for 14 days, respectively, and the viscosity change rate (%) was calculated based on the initial viscosity. bottom.
In addition, the viscosity was measured as follows. A 3° × R7.7 cone rotor was attached to an RE-105U viscometer (manufactured by Toki Sangyo Co., Ltd.), 0.15 ml of the target resin composition was set in the cone rotor, and the temperature was measured at 25 ° C. at 2.5 rpm. The viscosity of the resin composition was measured. If the measurement range is exceeded, the measurement is not possible. In addition, the standard of measurement range over is 1,200,000 mPa·s.

(Warm storage stability)
(1) Storage Stability After Heating at 40° C. The viscosity of the resin compositions of Examples and Comparative Examples was measured immediately after preparation (within 2 hours) and taken as the initial viscosity. After that, the resin compositions of Examples and Comparative Examples were heated at 40° C. for 2 hours, and the viscosity after standing at 25° C. for 7 days and the viscosity after standing at 25° C. for 14 days were measured. The viscosity change rate (%) was calculated based on the standard.

(2) Storage Stability after Heating at 50° C. The viscosity of the resin compositions of Examples and Comparative Examples was measured immediately after preparation (within 2 hours) and taken as the initial viscosity. After that, the resin compositions of Examples and Comparative Examples were heated at 50° C. for 2 hours, and the viscosity after standing at 25° C. for 7 days and the viscosity after standing at 25° C. for 14 days were measured. The viscosity change rate (%) was calculated based on the standard.
The viscosity was measured in the same manner as the liquid stability evaluation.

(Curability test)
Curability was measured for each of the cured pieces of the resin compositions of Examples and Comparative Examples, 1) when cured at 120°C for 1 hour, and 2) when cured at 120°C for 1 hour after UV 3000 mJ/ ^cm2 treatment. It was evaluated by the following methods.

Each cured piece obtained by curing under the above conditions was measured with an FT-IR measurement device (Spectrum one, manufactured by PerkinElmer) to evaluate curability. The following formula was used for calculating the epoxy curing rate. In the formula, the resin composition is an uncured product. A resin composition to which no isocyanate was added was used as a blank, and the difference from the blank was evaluated by ◯×.

Area where the reference peak exists; 1540 to 1480 cm ^-1 (near peak top 1510 cm ^-1 )
Area where epoxy group peak exists; 925 to 895 cm ^-1 (near peak top 910 cm ^-1 )
○: Curing rate is 0 to -20% with respect to the blank
×: Curing rate is less than -20% with respect to the blank

(Acetone washability test)
0.1 ml of the uncured resin compositions of Examples and Comparative Examples were placed in a 1 ml Terumo syringe, and linearly applied to a glass plate to a length of 2 cm. 200 ml of acetone was placed in a 300 ml beaker, and the composition applied to the slide glass was set upright in the beaker. After standing for 5 minutes, it was subjected to an ultrasonic cleaning device (device name: US-20PS manufactured by SND Co., Ltd.) for 5 minutes, then the glass plate was removed from the acetone bath, and the state of the glass was visually observed. evaluated with
x: The resin composition remains.
◯: No resin composition remained.

From the above results, the curable resin composition of the present invention has good curability and is superior in liquid stability and acetone washability to comparative examples containing no isocyanate compound. In addition, the curability is superior or the liquid stability is superior to those of Comparative Examples 9 to 12 in which a hydrazide-based curing agent is used as the latent curing agent.

(Amount of surface amine)
5.75 parts by mass of the curable resin composition of Example 41 and 5.75 parts by mass of the curable resin composition of Comparative Example 14 were separately dissolved in 20 parts by mass of acetonitrile, and suction filtration was performed using a 1 μm membrane filter. Furthermore, it was spray-washed with 15 parts by mass of acetonitrile. The filtered product was vacuum-dried at 25° C., and the product obtained from Example 41 was designated as processed product 1, and the product obtained from comparative example 14 was designated as processed product 2.
About 0.05 part by mass of each of the treated products 1 and 2 was separately collected in a vial bottle, and 20 parts by mass of a solution prepared by adjusting phenyl isocyanate to 20 ppm in methylcyclohexane was added.
It was placed in an ultrasonic cleaning tank (US-20PS manufactured by NSD Co., Ltd.) and dispersed for 3 minutes while applying ultrasonic waves. At this time, the vial was shaken by hand to disperse. After that, it was immersed in a hot water bath at 70°C for 1 hour. The vial was shaken by hand every 20 minutes. After immersing in a hot water bath at 70° C. for 1 hour, the mixture was placed in an ultrasonic cleaning tank, and the vial was shaken by hand while applying ultrasonic waves to disperse the mixture for 3 minutes.
After cooling to room temperature, the supernatant was taken in a syringe and filtered through a 0.2 μm filter made of PTFE. The absorbance of the filtrate was measured with a spectrophotometer (V-570 manufactured by JASCO Corporation). The absorbance at 226 nm of the 20 ppm phenyl isocyanate-methylcyclohexane solution and each sample was read with methylcyclohexane as a blank. Calculate the concentration of phenyl isocyanate using a phenyl isocyanate calibration curve prepared in advance, calculate the surface amino group amount (mmol) per 1 g of product 1 and treated product 1 from the concentration decrease, It was defined as the surface amine amount.
As a result, it was found that the treated product 2 had a surface amine amount of 0.77 mmol/g, and the treated product 1 had a surface amine amount of 0.10 mmol/g.
From this result, the treated material 1 obtained from Example 41 containing the latent curing agent (B) and the isocyanate compound (C) is higher than the treated material 2 obtained from Comparative Example 14 not containing the isocyanate compound (C). Also, the amount of surface amine is considerably reduced. Therefore, by mixing the curable resin (A), the latent curing agent (B) and the isocyanate compound (C), part or all of the latent curing agent (B) and part or all of the isocyanate compound (C) It was confirmed that all of them were reacting with each other, and that the surface amine amount of the latent curing agent (B) was reduced. These liquid stability evaluations were performed. Table 5 shows the results.

INDUSTRIAL APPLICABILITY The curable resin composition of the present invention can be suitably used, for example, as a sealant or encapsulant for electronic parts such as liquid crystal display panels, and is industrially useful.

Claims (6)

A curable resin composition comprising an epoxy resin (A), a latent curing agent (B), an isocyanate compound (C), a photopolymerization initiator (D) and a radical polymerization inhibitor,
Part of the latent curing agent (B) and part or all of the isocyanate compound (C) are reacted,
The latent curing agent (B) includes (b1) a carbazide compound, (b2) a compound obtained by adducting an imidazole compound to an epoxy resin, and (b3) a compound obtained by adducting a polyvalent amine compound to urea (where (b3) The polyvalent amine compounds in (b1) do not contain hydrazine, hydrazide compounds, and (b1) carbazide compounds), (b5) mixed crystals of one or more mono- or polyvalent amine compounds and one or more hydrazide compounds, and (b6 ) at least one selected from the group consisting of mixed crystals of one or more imidazole compounds and one or more hydrazide compounds,
A curable resin composition containing 0.02 to 28 parts by mass of an isocyanate compound (C) with respect to 100 parts by mass of the latent curing agent (B). 2. The curable resin composition according to claim 1, which is a sealant composition for liquid crystal display elements. The curable resin composition according to claim 1, further comprising an organic filler (F). Epoxy resin (A), latent curing agent (B), isocyanate compound (C), photopolymerization initiator (D) and radical polymerization inhibitor, with respect to 100 parts by mass of latent curing agent (B), isocyanate A method for producing a curable resin composition containing 0.02 to 28 parts by mass of the compound (C),
Epoxy resin (A), latent curing agent (B) and isocyanate compound (C), photopolymerization initiator (D) and radical polymerization without pre-reacting latent curing agent (B) and isocyanate compound (C) mixing an inhibitor;
The latent curing agent (B) includes (b1) a carbazide compound, (b2) a compound obtained by adducting an imidazole compound to an epoxy resin, and (b3) a polyvalent amine compound selected from the group consisting of an epoxy resin, an isocyanate compound, and urea. a compound adducted to at least one selected compound (wherein the polyamine compound in (b3) does not contain hydrazine, hydrazide compound, and (b1) carbazide compound), (b4) two or more hydrazides Mixed crystals of compounds, (b5) mixed crystals of one or more mono- or polyvalent amine compounds and one or more hydrazide compounds, and (b6) mixed crystals of one or more imidazole compounds and one or more hydrazide compounds is at least one selected from the group consisting of
A method for producing a curable resin composition. A liquid crystal display panel obtained using the curable resin composition according to any one of claims 1 to 3 . A method for manufacturing a liquid crystal display panel, wherein the curable resin composition according to any one of claims 1 to 3 is photocured and/or thermally cured in the liquid crystal dropping method.