JPH08176391A - Curable resin composition and film-forming material - Google Patents

Abstract

PURPOSE: To provide a curable resin composition containing a liquid resin produced by copolymerizing a polyalkylene glycol monoacrylate and an epoxy- containing monomer, etc., and a curing agent reactive with epoxy group, applicable without using a solvent and useful as a film-forming material, etc. CONSTITUTION: This curable resin composition applicable without using a solvent and useful as a film-forming material, etc., is produced by compounding (A) a liquid resin having a number-average molecular weight of 10,000-200,000 and a viscosity of 500-30,000cps at 50 deg.C and produced by the copolymerization of (i) 10-95wt.% of a monomer of formula I (R<1> is H or CH3 ; R<2> is a 4-22C alkyl) and/or formula II (R<3> is H or a 1-4C alkyl; (n) is an integer of 1-3; (m) is an integer of 4-25), (ii) 2-50wt.% of a vinyl monomer having epoxy group in the molecule and (iii) 0-20wt.% of other polymerizable vinyl monomer with (B) 0.01-10 equivalent (based on 1 equivalent of the epoxy group in the liquid resin of the component A) of a curing agent compound having >=2 functional groups bondable with epoxy group in one molecule.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition which can be coated or molded without using a solvent, and is then treated with heat to give a solid cured product. The resin composition of the present invention is for a film-forming material such as paint or ink, or
It is used as a solventless resin composition for adhesives, pressure sensitive adhesives, fillers, molding materials and surface modification materials.

[0002]

2. Description of the Related Art Conventionally, paints, adhesives, adhesives, inks,
Resin solutions containing organic solvents have been used as fillers and molding materials. These resin solutions scatter a large amount of organic solvents in the painting, filling and curing / drying steps. With increasing interest in the global environment and working environment, restrictions on the use of such resin solutions are being imposed. One of the methods is to use an aqueous solution of resin, powder, or hot-melt material, but the aqueous solution of resin contains a small amount of an organic solvent from the viewpoint of improving the coating property, and it is said that the odor in the working environment was eliminated. Hard to say. In addition to the incineration of the released organic solvent, investment is required for wastewater treatment. A painting and filling factory equipped with a large-scale exhaust gas treatment facility can suppress the release of organic solvents into the atmosphere, but a small factory without such equipment cannot treat wastewater even if it can treat organic solvents. Have. In addition, in the case of coating or filling powder or hot melt, it is necessary to introduce new equipment because the method is significantly different from the conventional painting and filling equipment.

In order to solve the above problems, high solidification of the resin solution and improvement of the aqueous solution of the resin have been carried out. Due to such efforts, the usage amount of the resin solution will become more prominent in the future. Conceivable. However, as a fundamental solution, there is a strong demand for the development of a solventless liquid resin which is free from problems such as pollution, safety and hygiene, ignition and explosion, can be widely applied, and is easy to apply and fill. Further, these solventless liquid resins need to be formed into a coating film or a molded product that is cured by a conventional drying device. Such a solventless resin composition is disclosed in JP-A-57-171.
This technique uses a liquid resin based on an acrylic monomer, but since the resulting resin is an oligomer and contains a residual monomer in the composition, further improvement is desired. In terms of physical properties, it is known that it is difficult to control the physical properties of the coating film after curing in the case of coatings composed of resins in the oligomer domain (Soichi Muroi, “1992 Adhesion and Painting Study Group Course”). Proceedings, 4 pages, 1993
Year), it is desired to increase the molecular weight while maintaining low viscosity.

[0004]

DISCLOSURE OF THE INVENTION The present invention does not contaminate the working environment of the coating process with the organic solvent that scatters and does not discharge the organic solvent into the atmosphere, and thus does not require special exhaust gas treatment equipment. Moreover, the coating that has been used conventionally,
It is intended to provide a resin composition which can be coated and filled by a filling method, for example, a roll coater or a knife coater, and does not dissipate the solvent even if a conventional heating and drying is performed to form a hard film or a molded product.

[0005]

Means for Solving the Problems As a result of intensive studies made by the present inventor to solve the above problems, a resin composition comprising a specific acrylic monomer and a vinyl monomer having an epoxy group has a high molecular weight. However, the present invention was found to be a resin composition which can be coated and filled by a conventional coating and filling method, and which reacts with a crosslinking agent having at least two functional groups capable of binding to an epoxy group to cure. It was

That is, the present invention provides (i): a monomer represented by the following formula (A-1) and / or formula (A-2): 10 to 95% by weight CH ₂ = C (R ¹ ) COO-R ² (A-1) (In the formula, R ¹ represents a hydrogen atom or CH ₃ , and R ² represents an alkyl group having 4 to 22 carbon atoms.) CH ₂ ═C (R ¹ ) COO (C _n H _2n O) _m R ³ (A-2) (In the formula, R ¹ is a hydrogen atom or CH ₃ , R ³ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, n is an integer of 1 to 3, and m is Each represents an integer of 4 to 25.) Copolymerizing 2 to 50% by weight of a vinyl monomer (B) having an epoxy group in the molecule and 0 to 20% by weight of another polymerizable vinyl monomer (C). Number average molecular weight of 10,000 to 20
50,000 and a viscosity at 50 ° C of 500 to 3
A liquid resin of 10,000 cps, and (ii):
A curing agent compound having two or more functional groups capable of binding to an epoxy group in one molecule is used as the epoxy group 1 in the liquid resin (i).
The present invention relates to a curable resin composition containing 0.01 to 10 equivalents relative to equivalents. Furthermore, in the present invention, the liquid resin (i) comprises a monomer (A-1) and a monomer (A-2) (A-1) :( A
-2) = 10: 90 to 90:10 (molar ratio) The above-mentioned curable resin composition which is the liquid resin (i) used in the ratio. Further, the present invention is that the liquid resin (i) is radical-polymerized in a solvent such that the monomer of the liquid resin (i) is a good solvent and the liquid resin (i) is a poor solvent. The present invention relates to the above curable resin composition. Further, the present invention relates to a substantially solvent-free film-forming material comprising a curable liquid resin composition to which a curing catalyst is added.

The acrylic monomer used in the present invention is an acrylic compound represented by the general formula (A-1) having an alkyl group at the carboxyl group of the acrylic compound or the general formula (A-2). It is a compound in which a poly (alkyleneoxy) group is bonded. The number of carbon atoms in the alkyl group is 4 or more and 22 or less, or the repeating unit of the alkyleneoxy group is 4 or more and 25.
The following cases are preferable.

The acrylic monomer represented by the formula (A-1) used in the present invention is used as a constituent component for making the resin liquid. As the alkyl group derivative, for example,
2-ethylhexyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, heptyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, Undecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate, nonadecyl (meth) acrylate 4 to 22 carbon atoms such as (meth) acrylate, icosyl (meth) acrylate, henicosyl (meth) acrylate, and docosyl (meth) acrylate
There are alkyl (meth) acrylates of which the carbon number is
Acrylates having 8 to 20 alkyl groups or the corresponding methacrylates are preferred. If the carbon number is 3 or less, it is difficult to obtain a liquid resin, and if the carbon number is 23 or more, the degree of polymerization does not easily increase, and at 50 ° C it is a solid, so a dedicated melting system is required for painting and filling. Is not preferable.

As the poly (alkyleneoxy) group derivative of the monomer (A-2), for example, tetraethylene glycol (meth) acrylate, methoxytetraethylene glycol (meth) acrylate, ethoxytetraethylene glycol (meth) acrylate, propoxy. Tetraethylene glycol (meth) acrylate, n-butoxytetraethylene glycol (meth) acrylate, n-
Pentoxytetraethylene glycol (meth) acrylate, tetrapropylene glycol (meth) acrylate, methoxytetrapropylene glycol (meth) acrylate, ethoxytetrapropylene glycol (meth) acrylate, propoxytetrapropylene glycol (meth) acrylate, n-butoxytetrapropylene Examples include glycol (meth) acrylate, n-pentaxytetrapropylene glycol (meth) acrylate, polyethylene glycol (meth) acrylate, methoxy polyethylene glycol (meth) acrylate, and ethoxy polyethylene glycol (meth) acrylate. The viscosity of the resin can be effectively reduced by using an acrylate having a polyoxyalkylene chain of 4 to 25, preferably 5 to 22 repeating units or a corresponding methacrylate. When the repeating unit is 3 or less, it is difficult to obtain a liquid resin, and when it is 26 or more, the degree of polymerization is hard to increase, and since it is a solid at 50 ° C, a dedicated melting system is required for painting and filling. Therefore, it is not preferable.

The amount of the monomer (A-1) or (A-2) used is 10 to 95% by weight, preferably 35 to 80% by weight, based on the liquid resin which is a copolymer. When the content of the monomer (A) in the coalescence is less than 35% by weight, especially 10% by weight, the liquid resin cannot maintain the low viscosity required for painting and filling, and on the contrary 80% by weight, especially 95% by weight. %, It is not preferable because a hard coating film cannot be obtained. Further, it is preferable to use the alkyl group derivative of the monomer (A-1) and the poly (alkyleneoxy) group derivative of the monomer (A-2) in combination because a decrease in viscosity is recognized. In this case, the ratio of the poly (alkyleneoxy) group derivative of the monomers (A-1) and (A-2) is preferably 1: 9 to 9: 1 (molar ratio).

Examples of the epoxy group-containing vinyl monomer (B) used in the present invention include glycidyl (meth) acrylate, glycidyl cinnamate, allyl glycidyl ether, vinylcyclohexene monoepoxide, and 1,3-butadiene. Examples include monoepoxide. You may use 2 or more types of these.

The vinyl monomer (B) having an epoxy group is used in an amount of 2 to 50% by weight, preferably 5 to 35% by weight, based on the entire liquid resin (i). If the content of component (B) is less than 5% by weight, especially less than 2% by weight, it becomes difficult to obtain a hard cured product. Conversely, if it exceeds 35% by weight, especially more than 50% by weight, the viscosity of the liquid resin becomes high and coating becomes difficult. Is not preferable.

The other polymerizable vinyl compound (C) used in the present invention can be used for improving the water resistance and hardness of the coating film. Specifically, aliphatic vinyl carboxylates such as vinyl acetate, aliphatic allyl carboxylates such as allyl acetate, allyl ethers such as allyl phenyl ether, alkyl (meth) acrylates such as methyl acrylate and ethyl methacrylate, styrene. , (Meth) acrylonitrile, (meth) acrylamide and the like. You may use 2 or more types of these.

The liquid resin of the present invention has a number average molecular weight (polystyrene conversion) value of 10,0 measured by GPC (gel permeation chromatograph) by adjusting the blending amount of the initiator.
It is synthesized in the range of 00 to 200,000, preferably 10,000 to 150,000. When the number average molecular weight is less than 10,000, it is difficult to isolate the resin component from the polymerization solution, and the mechanical properties of the cured product such as hardness and flexibility are deteriorated, solvent resistance, boiling water resistance, etc. Is not preferable, and when the number average molecular weight is more than 150,000, especially 200,000, the resin cannot maintain a coatable viscosity, which is not preferable.

Solubility parameter (sp value) of liquid resin (i)
Is 8.0 to 10.0 (cal / cm ³ ) ^1/2 , so methanol,
Ethanol, n-propanol, i-propanol, allyl alcohol, ethylene glycol, propylene glycol, methyl cellosolve, etc., sp value 10.0 (cal / cm ³ ) ^1/2 or more, preferably 11.5 (cal / cm ³ ) ^1/2 The use of the above solvent is preferable because only the liquid resin which has reached the preferable degree of polymerization is separated from the reaction solution, so that it is only necessary to remove the supernatant to isolate the resin component. In addition, dioxane, tetrahydrofuran, methanol, ethanol, n-propanol, i
-A water-miscible solvent such as propanol, methyl cellosolve, butyl cellosolve, methyl carbitol, or ethyl carbitol is preferably used because water can be added to isolate the resin component.

The liquid resin (i) used in the present invention can be produced by a solution method or a dispersion method of radical polymerization using a known radical polymerization initiator. The radical polymerization initiator used is not particularly limited, for example,
Peroxide systems such as benzoyl peroxide, t-butyl peroxide, cumene hydroperoxide, lauroyl peroxide,
Azo initiators such as azobisisobutyronitrile and azobiscyclohexanenitrile, and persulfate initiators such as potassium persulfate and ammonium persulfate can be used. The amount of such radical polymerization initiator is preferably 0.01 to 5% by weight, more preferably 0.1 to 5% by weight, based on the total amount of monomers.
3% by weight.

The viscosity of the obtained liquid resin (i) is preferably 500 to 30,000 cps at 50 ° C. measured by a rheometer (dynamic viscoelasticity measuring device), more preferably 800 to 20,000 cps. Is.

The liquid resin (i) used in the present invention
Examples of the curing agent compound (ii) having two or more functional groups capable of binding to the epoxy group in one molecule include oxalic acid,
Aliphatic dicarboxylic acids and their anhydrides such as malonic acid, succinic acid, glutaric acid, hexanedioic acid, citric acid, maleic acid, methyl nadic acid, ethylene glycol, diethylene glycol, glycerin, erythritol, arabitol, xylitol, sorbitol, dulcitol, mannitol. , Catechol, resorcin, hydroquinone, guaiacol, hexylresorcin, pyrogallol, trihydroxybenzene, phloroglysin, dimethylolphenol, trimethylolpropane, and other polyhydric alcohols or phenolic compounds, or their alkoxy modified products, hexamethylol Having an alkylol group or an alkoxy group such as melamine, hexamethoxymethylated melamine, and hexabutoxymethylated melamine Compounds, cyanuric acid, ammelide, melamine-down, benzoguanamine, diethanolamine, triethanolamine, amino resin-based compounds such as di-aminopyridine,

Tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, m-xylene diisocyanate, p-xylene diisocyanate, 1,5
-Naphthalene diisocyanate, lysine diisocyanate, hydrogenated 4,4'-diphenylmethane diisocyanate, diisocyanate such as hydrogenated tolylene diisocyanate,
Alternatively, an isocyanate adduct at both ends of these with glycols or diamines, triphenylmethane triisocyanate, polymethylene polyphenyl isocyanate, polyvalent isocyanate such as coronele L, amino acids such as glycine and alanine, and their lactams and citric acid , Hydroxycarboxylic acids such as 12-hydroxystearic acid and 6-hydroxypentanoic acid, and lactones thereof. You may use 2 or more types of these.

The composition amount of the curing agent compound (ii) is determined by the ratio of the epoxy group equivalent in the liquid resin (i) and the functional group equivalent in the curing agent compound (ii). 0.01 to 10 chemical equivalents, and preferably 0.1 to 5 chemical equivalents, relative to 1 equivalent of the epoxy group of When the functional group equivalent in the curing agent compound (ii) is less than 0.01 chemical equivalent to 1 equivalent of epoxy group of the liquid resin (i), a hard cured product cannot be obtained, and conversely, it is more than 10 chemical equivalents. In this case, the unreacted curing agent compound (ii) causes poor curing, which is not preferable.

The resin composition of the present invention can be used as a substantially solvent-free paint or molding material. However, in order to improve the fluidity of the resin, a small amount of water, an organic solvent or the like may be added within 5% by weight of the resin composition. In addition, titanium white, colorants such as various pigments,
A lubricant or the like may be added. When the resin composition of the present invention is treated with heat after coating or molding, the epoxy group derived from the vinyl monomer (B) having an epoxy group and the functional group derived from the curing agent compound (ii) are Then, the addition reaction occurs,
Can be cured.

A curing catalyst generally used for improving the curing characteristics of the curable liquid resin composition of the present invention can be used. Examples of typical curing catalysts include pyridine, 4-dimethylaminopyridine, pyridines such as 4-pyrrolidinopyridine, triethylamine, N, N'-dimethylaniline, N, N'-dimethylbenzylamine, and N, N. ,
Tertiary amines such as N ', N'-tetramethyl-1,3-butanediamine,

Organometallic compounds or organic complexes of metals such as diethylzinc, tetra (n-butoxy) titanium, dibutyltin dilaurate, dibutyltin di (2-ethylhexoate), sulfuric acid, zinc chloride, sodium hydroxide. Inorganic substances such as. The amount of such a curing catalyst added is preferably 0, with respect to the curable liquid resin composition.
It is from 01 to 1% by weight, preferably from 0.02 to 0.5% by weight. The heat treatment is preferably heating between 30 ° C and 250 ° C. The heat source is not particularly limited, but generally a heat circulation type oven or a heating roll is preferably used. The liquid resin of the present invention can also be used as a compatibilizer, an interface modifier, a pigment dispersant, and the like.

EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. In the example,
% Means% by weight

(Synthesis Examples 1 to 8) Monomer (A) and monomer (B) were placed in a 500 ml four-necked round bottom flask equipped with a stirrer, a nitrogen inlet tube, a temperature sensor, and a condenser.
Compounded in the composition shown in Table 1, using azobisisobutyronitrile (AIBN) as an initiator (1% by weight based on the total amount of charged monomers) in isopropanol (IPA) solvent (concentration when charged with monomers: 30% by weight) %) And refluxed for 5 hours to give a viscous resin solution. When the obtained resin solution was allowed to stand while cooling with ice, it was separated into two layers. After removing the upper layer, the lower layer was washed with petroleum ether and dried in a vacuum dryer for 12 hours to obtain a liquid resin. The number average molecular weight (Mn) in terms of styrene by gel permeation chromatography (Tosoh SC-8020) of the obtained liquid resin and the viscosity at 50 ° C. were measured using a rheometer (RFS-II, manufactured by Rheometrics). The measurement results of number average molecular weight and viscosity (50 ° C.) are shown in Table 1.

The compounds used in Examples and Comparative Examples are abbreviated as follows. LMA: Lauryl Methacrylate PMA: n-Pentyl Methacrylate BMA: n-Butyl Methacrylate PEG9MA: Methoxypolyethylene glycol methacrylate (Shin Nakamura Chemical Co., Ltd. M-90G) PEG4MA: Methoxytetraethylene glycol methacrylate GMA: Glycidyl methacrylate AGE: Allylglycidyl Ether HMDI: Hexamethylene diisocyanate IPDI: Isophorone diisocyanate CL: Coronate L (Toluylene diisocyanate modified trimethylolpropane manufactured by Nippon Polyurethane Industry Co., Ltd.) CY350: Methanol modified melamine manufactured by Cyanamid EG: Ethylene glycol TEA: Triethanolamine

Table 1 ─────────────────────────────── No. Epoxy Mn Viscosity 50 ℃ Monomer (A) Single Quantum (B) (A) :( B) (* 10 ⁴ ) (cps) ─────────────────────────────── --Synthesis Example 1 LMA GMA 90:10 1.0 9000 Synthesis Example 2 LMA AGE 94: 6 1.5 9500 Synthesis Example 3 PMA GMA 85:15 1.2 11000 Synthesis Example 4 PMA AGE 90:10 1.1 8900 Synthesis Example 5 PEG9MA GMA 89:11 1.1 7400 Synthesis example 6 PEG9MA AGE 90:10 1.2 8400 Synthesis example 7 PEG4MA GMA 93: 7 1.0 7900 Synthesis example 8 PEG4MA AGE 90:10 1.1 14000 Synthesis example 9 PEG9MA / LMA = 1/9 GMA 90:10 1.0 7800 Synthesis example 10 PEG9MA / LMA = 2/8 GMA 90:10 1.1 7300 Synthesis example 11 PEG9MA / LMA = 4/6 GMA 90:10 1.2 6800 Synthesis example 12 PEG9MA / LMA = 6/4 GMA 90:10 1.1 6300 Synthesis example 13 PEG9MA / LMA = 8/2 GMA 90:10 1.0 7100 Synthesis example 14 PEG9MA / LMA = 9/1 GMA 90:10 1.1 8000 Synthesis example 15 BMA GMA 90:10 1.1 12000 Synthesis example 16 BMA AGE 85:15 1.0 11500 ─── ───────────────────── ───────

The equivalent amount of the functional group of the curing agent compound (ii) was added as shown in Table 2 to 1 equivalent of the epoxy group in the liquid resin (i), and dimethylbenzylamine was added in an amount of 0.5 wt. Table 2 shows the pencil hardness after heating at 200 ° C for 20 minutes (% 0.5% applicator coated on an aluminum plate on a hot plate at 50 ° C). Further, in Examples 4 and 10, cobalt naphthenate was used instead of dimethylbenzylamine.

Table 2 ───────────────────────────────── No. Liquid resin (i) Curing agent (ii) Chemical equivalent of (ii) Pencil hardness after heating ────────────────────────────────── Example 1 Synthesis example 1 HMDI 1.0 H Example 2 Synthesis Example 2 IPDI 1.0 H Example 3 Synthesis Example 3 CL 1.0 3H Example 4 Synthesis Example 4 CY350 1.0 3H Example 5 Synthesis Example 5 EG 1.0 2H Example 6 Synthesis Example 6 TEA 1.0 2H Example 7 Synthetic Example 7 HMDI 1.0 3H Example 8 Synthetic Example 8 IPDI 1.0 H Example 9 Synthetic Example 7 CL 1.0 H Example 10 Synthetic Example 6 CY350 1.0 H Example 11 Synthetic Example 9 CY350 1.0 2H Example 12 Synthetic Example 10 CL 1.0 H Example 13 Synthetic Example 11 IPDI 1.0 3H Example 14 Synthetic Example 12 HMDI 1.0 2H Example 15 Synthetic Example 13 CY350 1.0 H Example 16 Synthetic Example 14 CL 1.0 2H Example 17 Synthetic Example 15 CY350 1.0 2H Example 18 Synthetic Example 15 CL 1.0 H Example 19 Synthesis Example 16 CY350 1.0 2H Example 20 Synthesis Example 16 HMDI 1.0 H Comparative Example 1 Comparative Example 5 − − 6B Softer Comparative Example 2 Synthesis Example 4 − − 6B Softer ────────────────────────────── ────

[0029]

EFFECTS OF THE INVENTION According to the present invention, the working environment of the coating process is not contaminated by the scattered organic solvent, and the organic solvent is not released into the atmosphere, so that no special exhaust gas treatment equipment is required and it has been used conventionally. The painting, filling method,
For example, a resin composition which can be coated and filled with a roll coater or a knife coater, and which does not disperse the solvent even when subjected to conventional heating and drying, and which is a hard coating or a molded product, can be simply provided.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location C09D 133/14 137/00 PGL

Claims (4)

[Claims] 1. (i): 10 to 95% by weight of a monomer represented by the following formula (A-1) and / or formula (A-2): CH ₂ ═C (R ¹ ) COO—R ² (A -1) (wherein, R ¹ represents a hydrogen atom or CH _3, R ² represents, respectively it an alkyl group having 4 to 22 carbon _{atoms.) CH 2 = C (R} 1) COO (C n H 2n O) _m R ³ (A-2) (In the formula, R ¹ is a hydrogen atom or CH ₃ , R ³ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, n is an integer of 1 to 3, and m is 4 to 25. Of the vinyl monomer having an epoxy group in the molecule (B) 2 to 50% by weight and other polymerizable vinyl monomer (C) 0 to 20% by weight. Average molecular weight 10,000 to 20
50,000 and a viscosity at 50 ° C of 500 to 3
A liquid resin of 10,000 cps, and (ii):
A curing agent compound having two or more functional groups capable of binding to an epoxy group in one molecule is used as the epoxy group 1 in the liquid resin (i).
A curable resin composition comprising 0.01 to 10 equivalents based on equivalents. 2. The liquid resin (i) comprises the monomer (A-1) and the monomer (A-2) (A-1) :( A-2) = 10: 90.
The curable resin composition according to claim 1, which is the liquid resin (i) used at a ratio of about 90:10 (molar ratio). 3. The liquid resin (i) is radical-polymerized in a solvent such that the monomer of the liquid resin (i) is a good solvent and the liquid resin (i) is a poor solvent. The curable resin composition according to claim 1. 4. A substantially solvent-free film-forming material, which is obtained by adding a curing catalyst to the curable liquid resin composition according to claim 1.