JPH0525361A - Curable resin composition - Google Patents

Abstract

PURPOSE:To obtain the subject composition, containing a 2-oxazoline group- containing compound, a carboxyl group-containing compound and an onium salt-based catalyst, curable at a relatively low temperature in a short time and excellent in mechanical strength, water and solvent resistance, etc. CONSTITUTION:The objective composition containing (A) a compound having plural 2-oxazoline groups, (B) a compound having plural carboxyl groups and (C) a catalyst composed of an onium salt compound. The component (A) is a polymer, prepared by polymerizing a monomer component composed of an addition polymerizable oxazoline compound expressed by at least the formula [R<1> to R<4> are H, halogen, alkyl, aralkyl or (substituted)phenyl; R<5> is acyclic organic group having addition polymerizable unsaturated bond] and having the plural 2-oxazoline groups as side chains and/or the component (B) is a polymer, obtained by polymerizing a monomer component composed of at least an unsaturated carboxylic acid and having the plural carboxyl groups as side chains.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention can be cured at a relatively low temperature (for example, 60 to 120 ° C.) in a short time (for example, 1 to 30 minutes). Produces a cured product with excellent strength, water resistance, solvent resistance, and adhesion to substrates, including paints (including coating agents), surface treatment agents, adhesives, sealing agents, adhesives, and fiber treatments. The present invention relates to a curable resin composition useful for applications such as agents and nonwoven fabric binders.

[0002]

2. Description of the Related Art The reaction between a 2-oxazoline group and a carboxyl group is known, and an ester amide bond: -CONH-CR (R ')-CR "(R"')-OCO- by the ring-opening reaction of the oxazoline group. Is known to produce. For example, Japanese Patent Publication Sho 44
Japanese Patent Publication No. 31821 discloses a method for producing a crosslinked resin by causing a poly-2-oxazoline compound to act on a polymer having a carboxyl group in a side chain. Also, Journal of Polymer Science, Polymer Chemistry Edition, Vol. 23, 180
Pp 5-1817 (1985) [Journal of Polymer S
cience: Polymer Chemistry Edition, Vol.23, 1805-18
17 (1985)], a method of crosslinking a copolymer containing pendant cyclic imino ether with a dicarboxylic acid is disclosed.

On the other hand, in JP-A-60-88038, a curable resin using a catalyst such as a strong acid, a sulfonic acid ester, a sulfuric acid ester or an alkyl halide for the reaction of a bis (2-oxazoline) compound with a dicarboxylic acid. Compositions are disclosed. Further, JP-A-59-1533 discloses a curable resin composition using a phosphite ester as a catalyst in the reaction of a bis (2-oxazoline) compound and a dicarboxylic acid.

[0004]

In a curable resin composition containing a polymer having a carboxyl group in the side chain and a poly-2-oxazoline compound, it is necessary to cure the composition at a temperature of 100 ° C. or higher for several hours. The cured product produced when cured under milder conditions is mechanical strength, water resistance,
All of the solvent resistance and the adhesion to the substrate could not be sufficiently satisfied, which was not practical.

In the curable resin composition containing a bis (2-oxazoline) compound, a dicarboxylic acid and the above catalyst,
A catalyst promotes the reaction between the amide group formed by the reaction between the oxazoline group and the carboxyl group and the 2-oxazoline group,
There is a problem that a high temperature of 140 ° C. or higher is required for curing in order to crosslink. The present invention has a relatively low temperature (for example, 60 to 120 ° C.) and a short time (for example, 1 to 3).
It can be cured in 0 minutes), and when cured, it produces a cured product with excellent mechanical strength, water resistance, solvent resistance, and adhesion to a substrate. It is an object of the present invention to provide a curable resin composition that is useful in applications such as surface treatment agents, adhesives, sealing agents, pressure-sensitive adhesives, fiber treatment agents, and nonwoven fabric binders.

[0006]

In order to solve the above problems, the present invention provides a compound (A) having a plurality of 2-oxazoline groups in the molecule, a compound (A) having a plurality of carboxyl groups in the molecule ( A curable resin composition containing B) and a catalyst (C), wherein the compound (A) is at least an addition-polymerizable oxazoline compound (a-1) represented by the following general formula (I). It is a polymer (A-1) obtained by polymerizing a body component (a) and having a plurality of 2-oxazoline groups as side chains, and / or the compound (B) is at least an unsaturated carboxylic acid. A polymer (B-1) having a plurality of carboxyl groups as side chains, which is obtained by polymerizing a monomer component (b) consisting of (b-1);
The catalyst (C) is at least one selected from onium salts.
There is provided a curable resin composition comprising two compounds.

[0007]

[Chemical 2]

In the present invention, the compound (A) and the compound (B) described below are used as reaction raw materials, but at least one of the compounds (A) and (B) is a polymer, that is, in the following cases and It is important that either one or both. The compound (A) is obtained by polymerizing at least the monomer component (a) consisting of the addition-polymerizable oxazoline compound (a-1) represented by the above general formula (I), and a plurality of 2- as a side chain is formed. It is a polymer (A-1) having an oxazoline group.

A polymer (B-1) obtained by polymerizing a monomer component (b) composed of at least an unsaturated carboxylic acid (b-1), the compound (B) having a plurality of carboxyl groups as side chains. ). The compound (A) used in the present invention is not particularly limited as long as it is a compound having two or more 2-oxazoline groups in the molecule, and for example,
A polymer having a plurality of 2-oxazoline groups as side chains, which is obtained by polymerizing at least a monomer component (a) composed of the addition-polymerizable oxazoline compound (a-1) represented by the general formula (I). (Hereinafter, "oxazoline group-containing polymer"
(A-1); and a polycarboxylic acid such as a dicarboxylic acid, a polynitrile other than the polymer (A-1) obtained by the reaction of a nitrile compound such as dinitrile or trinitrile with an ethanolamine. One or more of the oxazoline compounds (A-2).
As the compound (A), the oxazoline group-containing polymer (A-1) is more preferable than the polyoxazoline compound (A-2).
Is preferred. This is because the polymer (A-1) has a higher molecular weight and the number of 2-oxazoline groups contained in one molecule is larger, so that the polymer can be effectively crosslinked by a small reaction.
The 2-oxazoline group is represented by the following general formula (II). That is, the 2-oxazoline group may have one or more hydrogen atoms substituted.

[0010]

[Chemical 3]

The oxazoline group-containing polymer (A-1) is
It is obtained by polymerizing a monomer component (a) composed of at least an addition-polymerizable oxazoline compound (a-1), and preferably has a number average molecular weight of 500 or more, more preferably 1000 or more. The monomer component (a) can be copolymerized with the addition-polymerizable oxazoline compound (a-1) in addition to the addition-polymerizable oxazoline compound (a-1), if necessary, and
Addition-polymerizable compounds (a- that do not react with oxazoline groups)
It may contain one or more of 2).

Addition-polymerizable oxazoline compound (a-1)
As specific examples of, for example, 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline,
2-vinyl-5-methyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 2-isopropenyl-
4-methyl-2-oxazoline, 2-isopropenyl-
5-ethyl-2-oxazoline and the like can be mentioned, and one compound selected from these groups can be used alone, or two or more compounds can be mixed and used. Among them, 2-isopropenyl-2
-Oxazoline is suitable because it is easily available industrially.
The amount of the addition-polymerizable oxazoline compound (a-1) used is not particularly limited, but in the polymer (A-1), 1
It is preferably at least wt%. If the amount is less than 1% by weight, the degree of curing will be insufficient, and the water resistance and mechanical strength of the cured product will tend to be impaired.

The addition-polymerizable compound (a-2) used in the present invention means the addition-polymerizable oxazoline compound (a-
There is no particular limitation as long as it is an addition-polymerizable compound that is copolymerizable with 1) and does not react with an oxazoline group, and examples thereof include methyl (meth) acrylate, butyl (meth) acrylate, and (meth) acrylic acid 2 -(Meth) acrylic acid esters such as ethylhexyl; unsaturated nitriles such as (meth) acrylonitrile; (meth) acrylamide, N-
Unsaturated amides such as methylol (meth) acrylamide; vinyl esters such as vinyl acetate and vinyl propionate; vinyl ethers such as methyl vinyl ether and ethyl vinyl ether; α-olefins such as ethylene and propylene; vinyl chloride, vinylidene chloride, Halogenated α, β-unsaturated monomers such as vinyl fluoride; styrene,
Examples include α, β-unsaturated aromatic monomers such as α-methylstyrene, etc., and one of these compounds or a mixture of two or more thereof can be used.

The polymer (A-1) is obtained by polymerizing a monomer component (a) comprising at least an addition-polymerizable oxazoline compound (a-1) by a conventionally known polymerization method such as a suspension polymerization method, a solution polymerization method or an emulsion. It can be produced by a polymerization method or the like. Polymer (A-
Examples of the polyoxazoline compound (A-2) other than 1) include 2,2'-bis- (2-oxazoline), 2,2'-methylene-bis- (2-oxazoline), and 2,2'-. Ethylene-bis- (2-oxazoline), 2,2'-trimethylene-bis- (2-oxazoline), 2,2'-tetramethylene-bis- (2-oxazoline), 2,2'-hexamethylene-bis -(2-
Oxazoline), 2,2'-octamethylene-bis-
(2-oxazoline), 2,2'-ethylene-bis-
(4,4'-Dimethyl-2-oxazoline), 2,2 '
-P-phenylene-bis- (2-oxazoline), 2,
2'-m-phenylene-bis- (2-oxazoline),
2,2'-m-phenylene-bis- (4,4'-dimethyl-2-oxazoline), bis- (2-oxazolinylcyclohexane) sulfide, bis- (2-oxazolinylnorbornane) sulfide and the like can be mentioned. Any one of them may be used alone or two or more of them may be used in combination.

The compound (A) may be supplied in any form such as an organic solvent solution, an aqueous solution, a non-aqueous dispersion, an emulsion or a powder. The compound (B) used in the present invention is not particularly limited as long as it is a compound having two or more carboxyl groups in the molecule, and for example, a monomer including at least an unsaturated carboxylic acid (b-1). A polymer obtained by polymerizing the component (b) and having a plurality of carboxyl groups as side chains (hereinafter sometimes referred to as "carboxyl group-containing polymer") (B-1); and malonic acid, amber Acids, adipic acid, pimelic acid, speric acid, azelaic acid, sebacic acid, dodecanedioic acid and other aliphatic dicarboxylic acids, phthalic acid, isophthalic acid,
One or more of polycarboxylic acids (B-2) other than the polymer (B-1), such as aromatic dicarboxylic acids such as terephthalic acid, naphthalene dicarboxylic acid, diphenyl sulfone dicarboxylic acid and diphenylmethane dicarboxylic acid. Is.

The carboxyl group-containing polymer (B-1) is
It is formed by polymerizing a monomer component (b) composed of at least an unsaturated carboxylic acid (b-1) and has a number average molecular weight of 5
00 or more is preferable, and 1000 or more is more preferable. The monomer component (b) is an addition that is copolymerizable with the unsaturated carboxylic acid (b-1) as well as the unsaturated carboxylic acid (b-1) and does not react with a carboxyl group, if necessary. You may contain 1 or more types of polymeric compounds (b-2).

Examples of the unsaturated carboxylic acid (b-1) include unsaturated monocarboxylic acids such as (meth) acrylic acid, cinnamic acid and crotonic acid; unsaturated dicarboxylic acids such as maleic acid, itaconic acid and fumaric acid. Examples thereof include acids or their monoesters, and one kind or a mixture of two or more kinds selected from these groups can be used. The amount of the unsaturated carboxylic acid (b-1) used is not particularly limited, but it is 1 to 1 in the polymer (B-1).
A range of 20% by weight is preferred. If the amount used is less than 1% by weight, it cannot be a substantially effective amount in the reaction with the compound (A). On the contrary, if it exceeds 20% by weight, the water resistance of the cured product decreases, which is not preferable. In addition, as the compound (B),
The carboxyl group-containing polymer (B-1) is more preferable than the polycarboxylic acid (B-2) such as dicarboxylic acid. This is because the polymer (B-1) has a higher molecular weight and the number of carboxyl groups contained in one molecule is larger, so that the polymer (B-1) is effectively crosslinked by a small amount of reaction.

Other addition-polymerizable compounds (b-2) used in the present invention include the addition-polymerizable compounds (a) mentioned above.
-2) and the like, and other monomers having a functional group capable of reacting with an oxazoline group, such as 2-aminoethyl (meth) acrylate, glycidyl (meth) acrylate, and p-vinylphenol. And one or more of these can be used.

The polymer (B-1) can be produced by the same polymerization method as that for the polymer (A-1). The compound (B) may be supplied in any form such as an organic solvent solution, an aqueous solution, a non-aqueous dispersion, an emulsion, or a powder. In the present invention, the compounding ratio of the compound (A) and the compound (B) is not particularly limited,
For example, the molar ratio of the oxazoline group and the carboxyl group is preferably within the range of 20: 1 to 1:20. Compound (A)
The weight ratio of the compound (B) to the compound (B) is preferably 90:10 to 10:90. When it is out of this range, one of the 2-oxazoline group and the carboxyl group is decreased, an effective crosslinking reaction is not carried out, and the mechanical strength, water resistance, and
At least one of solvent resistance and adhesion to a substrate tends to be impaired.

In the present invention, it is important to use at least one compound selected from onium salts as a catalyst in order to accelerate the curing reaction of the compounds (A) and (B). The onium salt mentioned here is an ammonium salt, a sulfonium salt, an oxonium salt, an iodonium salt, a phosphonium salt, a nitronium salt, a nitrosonium salt, a diazonium salt, or the like. For example, monoammonium phosphate, diammonium phosphate, ammonium chloride,
Ammonium sulfate, ammonium nitrate, ammonium p-toluenesulfonate, ammonium sulfamate,
Ammonium salts of ammonium imidodisulfonate, tetrabutylammonium chloride, triethylbenzylammonium chloride, boron tetrafluoride tetrabutylammonium, phosphorus tetrafluoride tetrabutylammonium, tetrabutylammonium perchlorate, tetrabutylammonium sulfate, etc .; trimethyl iodide Sulfonium, boron tetrafluoride trimethylsulfonium, boron tetrafluoride diphenylmethylsulfonium, boron tetrafluoride benzyl tetramethylene sulfonium, antimony hexafluoride 2-butenyl tetramethylene sulfonium, antimony hexafluoride 3-methyl-2-butenyl Sulfonium salts such as tetramethylenesulfonium; oxonium salts such as boron tetrafluoride trimethyloxonium; diphenyliodonium chloride, boron tetrafluoride dif Iodonium salts such as niliodonium; Phosphonium salts such as antimony hexafluorocyanomethyltributylphosphonium and boron tetrafluoride ethoxycarbonylmethyltributylphosphonium; Nitronium salts such as nitronium boron tetrafluoride; Nitrosonium such as nitrosonium tetrafluoride Salts: diazonium salts such as 4-methoxybenzenediazonium chloride and the like can be used, and each can be used alone or in combination of two or more kinds.

The amount of the catalyst (C) used is preferably in the range of 0.1 to 10% by weight based on the total amount of the compound (A) and the compound (B). If it is less than 0.1% by weight, the desired cured product cannot be obtained because the catalytic action is substantially insufficient, and if it is added in excess of 10% by weight, the water resistance and mechanical strength of the cured product are adversely affected. Not preferable. The curable resin composition of the present invention is, for example, a plasticizer such as phthalic acid ester; a filler such as calcium carbonate, talc, clay, mica; , Pigments such as flower, zinc oxide, red bean, phthalocyanine; dyes;
Polyvinyl alcohol, hydroxyethyl cellulose,
A thickener such as starch; a dispersant; a wetting agent; a defoaming agent such as silicone may be optionally contained.

The method for producing the curable resin composition of the present invention is not particularly limited, and, for example, means commonly used by those skilled in the art can be widely applied. For example, a solution or dispersion or powder of the compound (A), a solution or dispersion or powder of the compound (B) and a solution or liquid or powder of the catalyst (C),
In addition, the above additives may be added and mixed as needed.

The curable resin composition of the present invention can be cured at a relatively low temperature (for example, 60 to 120 ° C.) in a short time (for example, 1 to 30 minutes). By thus curing, a cured product having excellent mechanical strength, water resistance, solvent resistance, and adhesion to a substrate is produced. Therefore, the curable resin composition of the present invention is useful for applications such as paints (including coating agents), surface treatment agents, adhesives, sealing agents, pressure-sensitive adhesives, fiber treatment agents, and nonwoven fabric binders.

[0024]

The curable resin composition of the present invention comprises the compound (A)
At least one of (B) and (B) is the specific polymer as described above, and since at least one compound of the onium salt is used as the catalyst, the catalyst activates the oxazoline group to form the carboxyl group. It is considered that the nucleophilic attack on the 5-position of the oxazoline ring of is easy to occur. Furthermore, since at least one of the oxazoline group and the carboxyl group is contained in the polymer, the temperature is lower than the conventional curing conditions (for example, 60 to 12).
Efficient cross-linking occurs at 0 ° C.) and / or short time (1 to 30 minutes), resulting in mechanical strength, water resistance, solvent resistance, and adhesion to a base material which are higher than those of conventional curable resin compositions. It produces a cured product that is excellent in everything.

[0025]

EXAMPLES Specific examples and comparative examples of the present invention will be shown below, but the present invention is not limited to the following examples.
In the following, "%" means "% by weight" and "part" means "part by weight" unless otherwise specified. -Production Example 1 (Production Example of Compound (A))-In a flask equipped with a stirrer, a reflux condenser, a nitrogen introduction tube, a thermometer and a dropping funnel, 782.4 parts of deionized water and Hitenol N-08 (No. 128 parts of 15% aqueous solution of polyoxyethylene nonyl phenyl ether sulfate ammonium salt manufactured by Ichigo Seiyaku Co., Ltd. was charged, pH was adjusted to 9.0 with an appropriate amount of ammonia water (28%), and the temperature was raised to 70 ° C. while slowly flowing nitrogen gas. Heated. 64 parts of a 5% aqueous solution of potassium persulfate was injected thereinto, and subsequently, a previously prepared monomer mixture consisting of 288 parts of butyl acrylate, 288 parts of styrene and 64 parts of 2-isopropenyl-2-oxazoline was prepared. It was added dropwise over 3 hours. During the reaction, nitrogen gas was continuously blown in, and the temperature in the flask was adjusted to 70
The temperature was kept at ± 1 ° C. After the dropping was completed, the same temperature was maintained for 2 hours, then the internal temperature was raised to 80 ° C., and stirring was continued for 1 hour to complete the reaction. Then, it is cooled and the nonvolatile content is 39.8%, p
H8.0 polymer aqueous dispersion containing oxazoline group (1)
Got This oxazoline group-containing polymer was insoluble in tetrahydrofuran and was a crosslinked product.

-Preparation Example 2 (Preparation Example of Compound (B))-A flask similar to that in Preparation Example 1 was charged with 782.4 parts of deionized water and 128 parts of a 15% aqueous solution of Hitenol N-08, and the mixture was gently mixed. The mixture was heated to 70 ° C while flowing nitrogen gas. 64 parts of a 5% aqueous solution of potassium persulfate was injected thereinto, and then butyl acrylate 320 prepared in advance was injected.
Part, 288 parts of styrene, and 32 parts of acrylic acid were added dropwise over 3 hours. Nitrogen gas was continuously blown during the reaction, and the temperature inside the flask was 70 ± 1 ° C.
Kept at. After the dropping was completed, the same temperature was maintained for 2 hours, then the internal temperature was raised to 80 ° C., and stirring was continued for 1 hour to complete the reaction. After cooling, a proper amount of ammonia water (28%)
The pH was adjusted to 8.5 with to obtain a carboxyl group-containing polymer aqueous dispersion (2) having a nonvolatile content of 39.8%. The carboxyl group-containing polymer had a number average molecular weight of 80,000.

-Production Example 3 (Production Example of Compound (A))-100 parts of xylene was charged into a flask equipped with a stirrer, a reflux condenser, a nitrogen introducing tube, a thermometer and a dropping funnel, and 9
The temperature was raised to 0 ° C. While blowing nitrogen gas into it,
To a monomer mixture consisting of 40 parts of methyl methacrylate, 40 parts of butyl acrylate and 20 parts of 2-isopropenyl-2-oxazoline, was added perbutyl O (t-butylperoxy-2-ethylhexano manufactured by NOF CORPORATION). A solution obtained by dissolving 5 parts of ate) was added dropwise over 3 hours, and the mixture was further held at the same temperature for 3 hours and then cooled to room temperature to obtain an oxazoline group-containing polymer solution (3) having a nonvolatile content of 49.8%.
Got The number average molecular weight of this oxazoline group-containing polymer was 9,000.

-Production Example 4 (Production Example of Compound (A))-Isopropyl alcohol 1 was placed in the same flask as in Production Example 3.
00 parts were charged and the temperature was raised to 80 ° C. While blowing nitrogen gas therein, perbutyl O (t-butylperoxy-2-ethylhexanoate manufactured by NOF Corporation) 5 was added to 100 parts of 2-isopropenyl-2-oxazoline.
A part of the solution was added dropwise over 3 hours, and the mixture was kept at the same temperature for 3 hours and then cooled to room temperature to obtain a nonvolatile content of 4
A 9.9% oxazoline group-containing polymer solution (4) was obtained. The number average molecular weight of this oxazoline group-containing polymer is 1
It was 600.

The symbols in Tables 1 to 4 below are as follows. The polyoxazoline compounds (A- used in Examples and Comparative Examples
2) * 1: 2,2'-tetramethylene-bis- (2-oxazoline) * 2: 2,2'-m-phenylene-bis- (2-oxazoline) Polycarboxylic acid used in Examples and Comparative Examples (B-2) * 3: Succinic acid * 4: Adipic acid catalyst (C) used in Examples and Comparative Examples * 5: Diammonium phosphate * 6: Benzyltriethylammonium chloride * 7: Boron tetrafluoride trimethylsulfonium * 8: Boron tetrafluoride trimethyloxonium * 9: Boron tetrafluoride diphenylmethylsulfonium * 10: Diphenyliodonium chloride * 11: Boron tetrafluoride ethoxycarbonylmethyl tributylphosphonium * 12: Boron tetrafluoride nitronium * 13: Tetrafluoride Nitrosonium boride * 14: 4-methoxybenzenediazonium chloride Used in Examples and Comparative Examples Combined * a: Oxazoline group-containing polymer aqueous dispersion (1) * b: Carboxyl group-containing polymer aqueous dispersion (2) * c: Oxazoline group-containing polymer solution (3) * d: Arolone 453 in isopropyl alcohol * E: Oxazoline group-containing polymer solution (4) -Examples 1 to 14-Oxazoline group-containing polymer aqueous dispersion (1) obtained in Production Example 1 and carboxyl group-containing polymer aqueous dispersion obtained in Production Example 2 A curable resin composition was prepared using the liquid (2), the polyoxazoline compound, the polycarboxylic acid, and the catalyst in the ratios shown in Tables 1 and 2.

Comparative Example 1 A curable resin composition was obtained in the same manner as in Examples 1 to 9 except that no catalyst was used in Examples 1 to 9. -Comparative Example 2-In Example 1, 2,2'-tetramethylene-bis- (2-oxazoline) was used instead of the oxazoline group-containing polymer, and succinic acid was used instead of the carboxyl group-containing polymer. A curable resin composition was obtained in the same manner as in Example 1 except that the above was used.

-Examples 15-28 and Comparative Examples 3-5-The compounding ingredients of the curable resin compositions of Examples 1-14 and Comparative Examples 1 and 2 above were well mixed to obtain 20 ± 0.5.
The film was cast on a plate of tetrafluoroethylene resin under the condition of 75 ° C. and 75 ± 3% RH, and then dried in air at room temperature (20 ° C.) for one day to prepare a film having a thickness of about 0.3 mm. The obtained film was further heat-cured under the conditions shown in Tables 1 and 2. The obtained cured film was used as a test piece and the following tests were conducted. The results are shown in Tables 1 and 2.

(1) Solvent resistance A test piece was immersed in acetone at room temperature for 72 hours, and its swelling rate and elution rate were calculated according to the following equations (1) and (2).

[0033]

[Equation 1]

[0034]

[Equation 2]

(2) Film Strength Using an Instron tensile tester, the tensile strength was measured at 10 cm / min. (3) The appearance of the film after immersing in water resistant water for 4 hours was observed. On the other hand,
After thoroughly mixing the compounding components of the curable resin compositions of Examples 1 to 14 and Comparative Examples 1 and 2, the kanakin cloth (1 mm thick) and the SUS plate (2 mm) under the following bonding conditions.
And the normal state adhesive strength and the water resistant adhesive strength were measured according to the following methods. The results are shown in Tables 1 and 2.

[Laminating Conditions] Coating amount: 12 g / 30 cm ² Coating method: Manual roll press condition: Press hardening at room temperature (20 ° C.) at 0.5 kg / cm ² for 3 hours: 120 ° C. for 5 minutes (4) Normal-state adhesive strength The 180-degree peeling strength at 20 ° C. and 60% RH was measured.

(5) Water-resistant adhesive strength: 180 ° in a wet condition by leaving it in water at 20 ° C. for 20 hours.
The peel strength was measured. The peeling strength was measured with an Instron tensile tester at a tensile speed of 30 cm / min.

[0038]

[Table 1]

[0039]

[Table 2]

As shown in Tables 1 and 2, the curable resin compositions of Examples produced cured products having excellent solvent resistance, film strength, water resistance and adhesive strength. The film strength represents mechanical strength, and the water resistant adhesive strength represents water resistance and adhesion. Comparative Example 5 is a case where the composition of Comparative Example 3 was completely cured. Comparative Examples 3 to 5 are inferior in all of solvent resistance, film strength, water resistance and adhesive strength.

-Examples 29 to 40- The oxazoline group-containing polymer solution (3) obtained in Preparation Example 3,
Commercially available carboxyl group-containing polymer solution ("Arolone 453" manufactured by Nippon Shokubai Co., Ltd. (carboxyl group-containing polymer obtained by copolymerizing 10% of acrylic acid, number average molecular weight 4000)
Isopropyl alcohol solution, non-volatile content 69%), the oxazoline group-containing polymer solution (4) obtained in Production Example 4, the polyoxazoline compound, the polycarboxylic acid, and the catalyst in the ratios shown in Tables 3 and 4. A curable resin composition was prepared.

-Comparative Example 6-A curable resin composition was obtained in the same manner as in Examples 29 to 35 except that no catalyst was used in Examples 29 to 35. —Comparative Example 7— In Example 29, 2,2′-m-phenylene-bis- (2-oxazoline) was used instead of the oxazoline group-containing polymer, and adipine was used instead of the carboxyl group-containing polymer. Example 29 except that an acid was used
A curable resin composition was obtained in the same manner as.

-Examples 41-52 and Comparative Examples 8-10
-The compounding components of the curable resin compositions of Examples 29 to 40 and Comparative Examples 6 and 7 were mixed well, and the obtained resin solution was cast on a plate made of tetrafluoroethylene resin. These were dried under reduced pressure at 90 mmHg for 24 hours at 20 ° C. to obtain a film having a thickness of about 0.3 mm. The obtained film was further heat-cured under the conditions shown in Tables 3 and 4. The obtained cured film was used as a test piece and the following tests were conducted. The results are shown in Tables 3 and 4.

(6) Curing rate The cured film was dipped in acetone for 24 hours, and the gel fraction was calculated by the following formula 3:

[0045]

[Equation 3]

Calculated according to On the other hand, Example 29 above
40 to 40 and the compounding components of the curable resin compositions of Comparative Examples 6 and 7, respectively, and then the resulting resin solution was cast on a steel plate and dried under reduced pressure in the same manner as above to obtain a film thickness of about 0. A coating of 1 mm was obtained. This coating film was cured by heating under the conditions shown in Tables 3 and 4. The following tests were conducted on the obtained cured coating film. The results are shown in Tables 3 and 4.

(7) Cross-cut test A test was conducted and evaluated according to Japanese Industrial Standard K-5400, 8.5.1. (8) Pencil Scratch Test According to Japanese Industrial Standard K-5401, a pencil scratch tester for coating film was used to perform a test with a load of 500 g.

(9) Solvent resistance test After rubbing the coating film with absorbent cotton containing methyl ethyl ketone 20 times, the appearance of the coating film was evaluated according to the following three grades from ⊚ to ∘. ⊚: No change. ◯: The gloss of the coating film is lost.

X: The coating film peels from the test plate. (10) Water resistance test The appearance of the coating film after immersing in water for 24 hours was observed.

[0050]

[Table 3]

[0051]

[Table 4]

As can be seen from Tables 3 and 4, the curable resin compositions of Examples had a high gel fraction, had little or no peeling in the cross cut test, had a high pencil hardness, and had a good solvent resistance and Good water resistance. The gel fraction is an index of the curing speed, and the higher the gel fraction, the faster the curing. The cross-cut test is an index of adhesion, and the larger the value, the better the adhesion. The pencil scratch test is an index of mechanical strength. The larger the numerical value before H, the larger the mechanical strength, and the smaller the mechanical strength in the order of HB and 1B. Comparative Example 10 is a case where the composition of Comparative Example 8 was completely cured. In Comparative Examples 8 to 10, curing speed, adhesion,
Poor mechanical strength, solvent resistance and water resistance.

[0053]

The curable resin composition of the present invention can be cured at a desired temperature and / or in a shorter time than conventional ones, and the cured product has mechanical strength, water resistance and solvent resistance. Excellent in all properties and adhesion to substrate.
Therefore, the curable resin composition of the present invention is useful for applications such as paints (including coating agents), surface treatment agents, adhesives, sealing agents, pressure-sensitive adhesives, fiber treatment agents, and nonwoven fabric binders.

Continued front page    (72) Inventor Goji Yamada             5-8 Nishiomitabicho, Suita City, Osaka Prefecture             Central Research Institute of Nippon Shokubai

Claims (3)

[Claims] 1. A curable resin composition comprising a compound (A) having a plurality of 2-oxazoline groups in the molecule, a compound (B) having a plurality of carboxyl groups in the molecule, and a catalyst (C). The compound (A) is obtained by polymerizing a monomer component (a) composed of at least an addition-polymerizable oxazoline compound (a-1) represented by the following general formula (I), and a plurality of side chains are provided. Is a polymer (A-1) having a 2-oxazoline group, and / or the compound (B) polymerizes a monomer component (b) containing at least an unsaturated carboxylic acid (b-1). Which is a polymer (B-1) having a plurality of carboxyl groups as side chains;
The catalyst (C) is at least one selected from onium salts.
A curable resin composition comprising two compounds. [Chemical 1] 2. The polymer (A-1) is a copolymer of an addition-polymerizable oxazoline compound (a-1) and an addition-polymerizable compound (a-2) that does not react with a 2-oxazoline group. Item 1. The curable resin composition according to item 1. 3. The polymer (B-1) is a copolymer of an unsaturated carboxylic acid (b-1) and an addition polymerizable compound (b-2) that does not react with a carboxyl group, or Two
The curable resin composition described.