JP2001049214A - Adhesive resin composition and its use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an adhesive resin composition having good ordinary-state and water-resistant adhesive strengths and being excellent in one-package stability and advantageous in cost by adding an oxazoline-group-containing polymer to a vinyl acetate resin emulsion. SOLUTION: This composition comprises (A) 100 pts.wt. vinyl acetate resin emulsion, desirably, emulsion based on an ethylene/vinyl acetate copolymer, further containing carboxy groups, and having an acid value of the resin solids of at most 50 mgKOH/g and (B) 1-50 pts.wt. polymer having oxazoline groups as side chains, obtained by copolymerizing an addition-polymerizable oxazoline compound represented by the formula (wherein R1 to R4 are each H, a halogen, an alkyl, an aralkyl, an aryl, or a substituted aryl; and R5 is an addition- polymerizable-unsaturation-containing acyclic organic group) with other comonomers. This composition can be desirably used as an adhesive for bonding a porous adherend to a thermoplastic resin adherend.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive resin composition useful for applications such as surface treatment agents for adhesives and films, and coating agents.

[0002]

2. Description of the Related Art Conventionally, for bonding plastic materials such as vinyl chloride resin and polyolefin resin, wood, paper, concrete, etc., ethylene-vinyl acetate resin emulsions and acrylate-vinyl acetate resin emulsions have been mainly used. An adhesive as a component is used.

As adhesives having improved water resistance, adhesives in which a crosslink is formed by mixing an isocyanate compound with the emulsion are widely known. For example, in Japanese Patent Publication No. 51-30577,
A water-resistant adhesive obtained by dissolving an isocyanate-based compound in a solvent and dispersing it in an aqueous solution or an aqueous emulsion containing polyvinyl alcohol is disclosed.

[0004] However, such an adhesive cross-linked with an isocyanate-based compound has a problem in that although it has excellent water resistance, it has low storage stability and a short pot life, so that one-packing is difficult. Had.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to have good normal state and water-resistant adhesive strength,
An object of the present invention is to provide an adhesive resin composition having excellent one-pack stability.

[0006]

Means for Solving the Problems The present inventor has made intensive studies to solve the above-mentioned problems. As a result, by adding the oxazoline group-containing polymer to the vinyl acetate resin-based emulsion, it is possible to improve not only the water-resistant adhesiveness but also the adhesion to the base material. And completed the present invention.

That is, the adhesive resin composition of the present invention comprises:
It comprises a vinyl acetate resin-based emulsion (A) and an oxazoline group-containing polymer (B) as essential components.
The adhesive of the present invention is an adhesive used for bonding a porous substrate and a thermoplastic resin substrate, and is characterized by being composed of the adhesive resin composition. The laminate of the present invention is obtained by bonding a porous substrate and a thermoplastic resin substrate via the adhesive resin composition.

[0008] The adhesive substrate of the present invention is obtained by applying the adhesive resin composition.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail. The adhesive (adhesive) resin composition of the present invention (hereinafter simply referred to as “adhesive resin composition”) is a vinyl acetate resin emulsion (A).
Is an essential component. The vinyl acetate resin-based emulsion (A) has good compatibility with wood, plywood, paper, and the like, and can exhibit good adhesion and adhesion when used as an adherend. In general, vinyl acetate resin-based emulsions are inexpensive and can be used as adhesive resin compositions that are advantageous in cost.

The vinyl acetate resin emulsion (A) in the present invention is obtained by emulsion polymerization of a vinyl acetate monomer alone or a vinyl acetate monomer and a monomer copolymerizable with the vinyl acetate monomer. The monomer copolymerizable with the vinyl acetate monomer includes, for example, ethylene; (meth) acrylates such as methyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate; and maleic ester , Dicarboxylic acid esters such as crotonic acid esters; N
-N-methylol derivative monomers such as methylol acrylamide and N-butoxymethylol acrylamide; having carboxyl group-containing monomers including acrylic acid and other functional groups such as sulfonic acid groups, epoxy groups, amino groups, and amide groups. Various monomers; and the like. One or more of these can be used.

As the vinyl acetate resin emulsion (A) in the present invention, it is particularly preferable that an ethylene-vinyl acetate copolymer is a main component of the vinyl acetate resin emulsion (A). Thereby, good adhesion to a plastic substrate such as vinyl chloride or polyolefin can be imparted. The content of ethylene in the ethylene-vinyl acetate copolymer is 5 to 45% by weight.
It is preferable that If the ethylene content is less than 5% by weight, the cohesive strength of the polymer is insufficient, and it is difficult to obtain sufficient adhesive strength. On the other hand, if it exceeds 45% by weight, the adhesiveness to the adherend may be reduced. This is not preferred. The amount (solid content) of the ethylene-vinyl acetate copolymer is 30 to 100% by weight, preferably 60 to 100% by weight, based on the total solid content of the vinyl acetate resin emulsion (A) as 100% by weight. % Is preferable.

In the present invention, the vinyl acetate resin emulsion (A) preferably contains a carboxyl group. The adhesive resin composition of the present invention contains the oxazoline group-containing polymer (B) described later as an essential component. The oxazoline group-containing polymer is contained in the vinyl acetate resin-based emulsion (A) by containing a carboxyl group. By forming a crosslinked structure between the oxazoline group and the carboxyl group in the polymer (B), the adhesiveness of the resulting adhesive fat composition to an adherend and the water-resistant adhesiveness can be further improved.

The means for introducing a carboxyl group into the vinyl acetate resin emulsion (A) is not particularly limited. For example, when a polymer component of the vinyl acetate resin emulsion (A) is obtained, acetic acid may be used. A method in which a carboxyl group-containing unsaturated monomer copolymerizable with a vinyl monomer is copolymerized as a part of the copolymerization monomer, or a carboxyl group-containing unsaturated monomer is used as a component other than the polymer component of the vinyl acetate resin emulsion (A). There is a method of adding and containing a compound. For more information,
As a means for containing a carboxyl group-containing compound in, for example, when a part of the carboxyl group-containing unsaturated monomer used as a copolymerization monomer in the method remains in the emulsion system without copolymerization The residual unsaturated monomer having a carboxyl group can be treated as an acid component (the compound having a carboxyl group). In this case, the residual amount and the presence state of the carboxyl group are not particularly limited as long as the acid value of the resin solid of the emulsion (A) is within the range described below. As a means for introducing a carboxyl group, a method of copolymerizing a carboxyl group-containing unsaturated monomer is preferable, and a method of using a carboxyl group-modified compound as a protective colloid, which is one of the methods, is preferable. .

When the carboxyl group-containing unsaturated monomer is copolymerized, the carboxyl group-containing unsaturated monomer copolymerizable with the vinyl acetate monomer is not particularly limited. Unsaturated monomers such as acrylic acid, methacrylic acid and crotonic acid; maleic acid,
Unsaturated dicarboxylic acids such as fumaric acid and itaconic acid; and the like. These may be used alone or in combination of two or more.

When the carboxyl group-containing unsaturated monomer is copolymerized with vinyl acetate, the amount of the carboxyl group-containing unsaturated monomer used is not particularly limited,
5 to the total amount of all monomers including vinyl acetate monomer
% By weight or less. If the amount of the carboxyl group-containing unsaturated monomer exceeds 5% by weight, the water resistance of the adhesive resin composition tends to decrease, which is not preferable.

As a means for introducing a carboxyl group into the vinyl acetate resin emulsion (A), a method using a carboxyl group-modified polyvinyl alcohol, which is an example of a carboxyl group-modified compound, as a protective colloid at the time of emulsion polymerization is employed. In this case, the saponification degree of the carboxyl group-modified polyvinyl alcohol is not particularly limited, but is preferably 80 to 99 mol%. If the saponification degree is less than 80 mol%, the water resistance of the dried film of the adhesive resin composition tends to decrease, while if it exceeds 99 mol%, the stability during emulsion polymerization may be deteriorated. This is not preferred. The average degree of polymerization of the carboxyl group-modified polyvinyl alcohol is not particularly limited, but is preferably from 1,000 to 2,500, and
~ 2000 is more preferred. When the average degree of polymerization is less than 1000, the dry film strength of the obtained adhesive resin composition tends to decrease, while when it exceeds 2500, the viscosity of the obtained adhesive resin composition becomes too high,
Not preferred.

When the carboxyl group-modified polyvinyl alcohol is used as a protective colloid, its use amount is not particularly limited, but is 0 to the total amount of the vinyl acetate monomer and the monomer copolymerizable with the vinyl acetate monomer. And preferably from 1 to 30% by weight.
More preferably, the content is set to about 20% by weight. 0.1% by weight of carboxyl group-modified polyvinyl alcohol
If the amount is less than 30%, the initial polymerization tends to be difficult to occur. On the other hand, if the amount exceeds 30% by weight, the dry film strength of the obtained adhesive resin composition may decrease, which is not preferable.

In the present invention, the blending amount (solid content) of the vinyl acetate resin emulsion (A) is preferably 20 to 100% by weight based on the resin solid content of the whole composition. The vinyl acetate resin emulsion (A) in the present invention has an acid value of 50 mgKOH / g of the resin solid content.
The following is preferred. Acid value of resin solid content is 50m
If it exceeds gKOH / g, the water resistance of the obtained adhesive resin composition may decrease, which is not preferable.

The emulsion polymerization method for obtaining the vinyl acetate resin emulsion (A) is not particularly limited, and various conventionally known emulsion polymerization methods can be employed.
Examples of the emulsifier used in the emulsion polymerization for obtaining the vinyl acetate resin emulsion (A) include a protective colloid, a nonionic or cationic surfactant, and the like. These emulsifiers may be used alone or in combination of two or more.

Examples of the protective colloid include water-soluble polymers such as polyvinyl alcohols such as partially saponified polyvinyl alcohol and carboxyl group-modified polyvinyl alcohol; and cellulose derivatives such as hydroxyethyl cellulose. Among these, polyvinyl alcohols are preferred, and carboxyl group-modified polyvinyl alcohol is particularly preferred. As the protective colloid, those having an average degree of saponification of 7 to 99.5 mol% and an average degree of polymerization of 700 to 2700 are particularly preferable.

The amount of the emulsifier to be used is not particularly limited, but is 0.1% based on the total amount of the vinyl acetate monomer and the monomer copolymerizable with the vinyl acetate monomer.
The content is preferably 3 to 15% by weight. The amount of the emulsifier used is 0.
If the amount is less than 3% by weight, the stability of the emulsion may be impaired. On the other hand, if it exceeds 15% by weight, the viscosity of the emulsion tends to increase, which is not preferable.

The adhesive resin composition of the present invention contains the oxazoline group-containing polymer (B) as an essential component. By blending the oxazoline group-containing polymer (B),
In general, it can exhibit excellent adhesion even to adherends having low adhesion to a resin composition, for example, a vinyl chloride substrate or a polyolefin substrate. Liquid stability can be improved. Further, when the vinyl acetate resin emulsion (A) contains a carboxyl group, a crosslink is formed between the emulsion and the carboxyl group, and the water resistance of the obtained adhesive resin composition can be improved.

The oxazoline group-containing polymer (B) in the present invention comprises an addition polymerizable oxazoline compound represented by the following general formula (1) and, if necessary, one or more other copolymerizable monomers. It is a polymer obtained by polymerization and having an oxazoline group in a side chain.

[0024]

Embedded image

[0025] _{(wherein, R 1, R 2, R} 3, R 4 are each independently a hydrogen atom, a halogen atom, an alkyl group, an aralkyl group, an aryl group or a substituted aryl group,, R ₅ is (Acyclic organic group having an addition-polymerizable unsaturated bond) Specific examples of the addition-polymerizable oxazoline compound represented by the general formula (1) include, for example, 2-vinyl-2-oxazoline and 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. These may be used alone or in combination of two or more. Among them, in particular, 2
-Isopropenyl-2-oxazoline is preferred because it is easily available industrially.

If necessary, the other copolymerizable monomer copolymerized with the addition-polymerizable oxazoline compound may be a monomer that does not react with the oxazoline group and is copolymerizable with the addition-polymerizable oxazoline compound. There is no particular limitation as long as it is present. For example, methyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, 2-hydroxy (meth) acrylate (Meth) acrylic esters such as ethyl, 2-aminoethyl (meth) acrylate, and salts thereof; unsaturated nitriles such as (meth) acrylonitrile; (meth) acrylamide, N-methylol (meth) acrylamide; Unsaturated amides such as N- (2-hydroxyethyl) (meth) acrylamide; vinyl acetate, propion Vinyl esters such as vinyl; vinyl ethers such as methyl vinyl ether and ethyl vinyl ether; α-olefins such as ethylene and propylene; halogen-containing α, β-unsaturated monomers such as vinyl chloride, vinylidene chloride and vinyl fluoride Α, β such as styrene, α-methylstyrene, sodium styrenesulfonate;
-Unsaturated aromatic monomers; They are,
One or two or more can be used.

The amount of the addition-polymerizable oxazoline compound used is not particularly limited, but should be at least 5% by weight based on all monomers used for obtaining the oxazoline group-containing polymer (B). Is preferred, and more preferably 10 to
70% by weight. More preferably, 20 to 60% by weight
And most preferably 30 to 60% by weight. If the amount of the addition-polymerizable oxazoline compound is less than 5% by weight, it is difficult to obtain sufficient adhesion to an adherend such as a vinyl chloride substrate or a polyolefin substrate, which is not preferable. If the use amount of the addition-polymerizable oxazoline compound exceeds 60% by weight, the water resistance of the obtained adhesive resin composition may decrease, which is not preferable.

The oxazoline group-containing polymer (B) in the present invention is desirably used as an aqueous solution or an aqueous dispersion. The aqueous solution of the oxazoline group-containing polymer (B) may be, for example, 50% by weight or more of a hydrophilic monomer in all the monomers used for obtaining the oxazoline group-containing polymer (B). More preferably, it can be obtained by imparting water solubility to the oxazoline group-containing polymer (B) at 60 to 90% by weight. Examples of the hydrophilic monomer include 2-hydroxyethyl (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, a monoester of (meth) acrylic acid and polyethylene glycol, and (meth) acrylic acid 2
-Aminoethyl and its salts, sodium (meth) acrylate, ammonium (meth) acrylate, (meth) acrylamide, N-methylol (meth) acrylamide and the like. Of these, monomers having a polyethylene glycol chain, such as methoxypolyethylene glycol (meth) acrylate, and a monoester of (meth) acrylic acid and polyethylene glycol, which are highly soluble in water, are particularly preferable.

The aqueous solution of the oxazoline group-containing polymer (B) is prepared by subjecting the addition-polymerizable oxazoline compound and, if necessary, the above-mentioned hydrophilic monomer to solution polymerization in an aqueous medium by a conventionally known polymerization method. Can be produced. The aqueous medium that can be used is not particularly limited as long as it can be easily mixed with water, and includes water alone, a mixture of water and an organic solvent, and an organic solvent alone. Mixtures with solvents are preferred. Usable organic solvents include methanol, ethanol, propanol, isopropanol, butanol,
Examples thereof include t-butanol, ethylene glycol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, diethylene glycol, acetone, and methyl ethyl ketone, and one or more of these can be used.

The aqueous dispersion of the oxazoline group-containing polymer (B) is prepared, for example, by using the above-mentioned addition-polymerizable oxazoline compound and, if necessary, one or more of the above-mentioned copolymerizable monomers.
It can be obtained by performing emulsion polymerization or suspension polymerization in an aqueous medium by a conventionally known polymerization method. Examples of the aqueous medium that can be used include those similar to the aqueous medium used to obtain the aqueous solution of the oxazoline group-containing polymer (B).

As another method for obtaining an aqueous dispersion of the oxazoline group-containing polymer (B), an oxazoline group-containing polymer (B) produced by a known polymerization method may be added with an emulsifier or a dispersant, if necessary. And a method of post-dispersion in the aqueous medium. In the present invention, the blending amount of the oxazoline group-containing polymer (B) is preferably 1 to 50 parts by weight based on 100 parts by weight of the vinyl acetate resin emulsion (A) on a solid basis. When the resin solid content of the aqueous solution or aqueous dispersion of the oxazoline group-containing polymer (B) is less than 1 part by weight based on 100 parts by weight of the vinyl acetate resin emulsion (A),
The adhesiveness of the resulting adhesive resin composition to a substrate such as vinyl chloride or polyolefin and the water resistance tend to decrease. On the other hand, if it exceeds 50 parts by weight, the oxazoline group-containing polymer (B) and vinyl acetate There is a tendency that miscibility with the resin emulsion (A) tends to decrease.

In the adhesive resin composition of the present invention, other polymers or polymer solutions can be used in combination as long as the effects of the present invention are not impaired. The type of polymer or polymer solution that can be used in combination in the present invention is not particularly limited. Also, the amount of addition is not particularly limited. Specific examples include aqueous solutions and aqueous dispersions of polymers such as acryl, urethane, polyester, polyamide, polyolefin, and polyamine. These may of course be used as a mixture if desired. Among these, a urethane resin-based emulsion, which is a urethane resin aqueous dispersion, is particularly preferred.
When a urethane resin-based emulsion is used in combination in the adhesive resin composition of the present invention, the content of the urethane resin-based emulsion is not particularly limited, but is preferably, for example, 1 to 30% by weight in the adhesive resin composition. In addition, usually, the solid content concentration of the polymer aqueous solution, dispersion, and emulsion is preferably about 20 to 70% by weight.

[0033] The adhesive resin composition of the present invention may optionally contain a curing agent. As a curing agent,
Although not particularly limited, a compound having two or more functional groups capable of reacting with an acid group and / or a hydroxyl group in a molecule is preferable. Specifically, for example, isocyanate-based,
Melamine-based, aziridine-based, epoxy-based, carbodiimide-based curing agents; various chelating-type curing agents;
Among these, isocyanate-based, epoxy-based, and carbodiimide-based curing agents are preferred. Particularly, as the isocyanate-based curing agent, for example, tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), hexamethylene diisocyanate (HD)
Diisocyanate compounds such as I); dimers or trimers of these diisocyanate compounds; polyisocyanate compounds which are modified products thereof; and the like. Among these, those obtained by modifying a polyisocyanate compound with a sulfonic acid group, a carboxyl group, or a nonionic hydrophilic group such as polyethylene glycol are preferred. Such a polyisocyanate compound modified by a hydrophilic segment is generally called a water-dispersed isocyanate, and is widely used as an aqueous curing agent.

The adhesive resin composition of the present invention may further contain, if necessary, for example, a tackifier, a surfactant, a plasticizer, a filler, a pigment within a range that does not impair the performance of the adhesive resin composition. , Dyes, stabilizers, antioxidants, UV absorbers,
One or more of various additives such as an antifoaming agent and a preservative may be contained. The total content of the vinyl acetate resin-based emulsion (A) and the oxazoline group-containing polymer (B) in the adhesive resin composition of the present invention is not particularly limited, but preferably, the adhesive is used. 1 to 100% by weight, more preferably 5 to 10% by weight in the conductive resin composition
The content is preferably 0% by weight, more preferably 10 to 100% by weight.

As a substrate to which the adhesive resin composition of the present invention can be applied, for example, a porous substrate such as a wood or cellulose substrate is preferable. More specifically, it is a rawan plywood, an MDF board, a particle board, a solid material or the like.
In addition, a plastic substrate such as a thermoplastic resin substrate, a surface of a cured coating film of a thermosetting resin, a surface of a cured product thereof, and the like can also be suitably used as the substrate. Also, cement board,
Inorganic materials such as gypsum board and ALC are also suitable as the base material. Since the adhesive resin composition of the present invention is excellent in one-pack stability and exhibits good normal state and water-resistant adhesiveness, for example, an adhesive for bonding different kinds or the same kind of these base materials (for example, for plywood) (Wood / wood, wood / plastic), packaging (paper / paper, paper / plastic), and automotive coatings. It is preferably used as a primer coating (primer coating) or the like.

The adhesive of the present invention is an adhesive used for bonding a porous substrate such as wood or a cellulose substrate to a thermoplastic resin substrate, and comprises the above-mentioned adhesive resin composition. . The thermoplastic resin substrate is not particularly limited, but for example, a substrate of vinyl chloride, polyolefin, polyester resin, polycarbonate resin, or the like is preferable. In particular, an adhesive used for a vinyl chloride base material and a polyolefin base material is preferable because it exhibits excellent adhesion. In particular, when a vinyl chloride substrate is used as the adherend, an aqueous solution of an oxazoline group-containing polymer having a glass transition temperature of 0 to 80 ° C is used as the oxazoline group-containing polymer contained in the adhesive resin composition. Preferably, when a polyolefin substrate is used as the adherend, the oxazoline group-containing polymer contained in the adhesive resin composition has a glass transition temperature of -70 to 20 ° C, preferably -50 to -20. It is preferable to use an aqueous dispersion of an oxazoline group-containing polymer at a temperature of ° C.

The adhesive of the present invention can also be effectively used for bonding the above-mentioned thermoplastic resin substrates. Further, the adhesive of the present invention, acrylic resin, epoxy resin,
When a thermosetting resin such as a curable polyester resin or the like is bonded to a cured resin film or a cured product thereof or a molded product thereof, a cellulose substrate (eg, paper), wood, inorganic Even when a material (for example, cement board, gypsum board, ALC, or the like) is bonded, excellent adhesiveness can be exhibited.

The laminate of the present invention is obtained by bonding a porous substrate such as a wood or cellulose substrate and a thermoplastic resin substrate via the adhesive resin composition. Since the adhesive resin composition has excellent adhesion to these substrates as described above, and has good normal state and water-resistant adhesiveness, the laminate of the present invention exhibits excellent peel strength. can do. The thermoplastic resin substrate is not particularly limited, but includes, for example, substrates such as vinyl chloride, polyolefin, polyester resin, and polycarbonate resin.In particular, a vinyl chloride substrate and a polyolefin substrate are excellent. It is preferable because it exhibits adhesiveness.

The method for producing the laminate of the present invention is not particularly limited. For example, an adhesive resin composition is applied to at least one of the porous substrate and the thermoplastic resin substrate, and Before the moisture in the adhesive resin composition is completely dried, wet lamination in which the porous substrate is bonded to the thermoplastic resin substrate, or the moisture in the applied adhesive resin composition is dried. Thereafter, dry lamination in which both substrates are bonded to each other can be employed.

The adhesive base material of the present invention is obtained by applying the adhesive resin composition. Specifically, for example, after dry coating the adhesive resin composition on a substrate,
It is dried, and if necessary, the coated surface is covered with release paper, and the resulting product is exemplified. The substrate is not particularly limited,
For example, it may be appropriately selected from the above-described base materials according to the purpose.

[0041]

EXAMPLES Examples and comparative examples according to the present invention will be described below, but the present invention is not limited by these examples. The “parts” described in the examples and comparative examples indicate “parts by weight”. First, a production example of the vinyl acetate resin emulsion (A) and the oxazoline group-containing polymer (B) will be described.

[Vinyl acetate resin emulsion (A1)
Production Example] Ethylene / vinyl acetate / acrylic acid was used at a copolymerization ratio of 25/72/3 (% by weight), and 10% by weight of polyvinyl alcohol (commercially available) based on the total amount of vinyl acetate and acrylic acid Emulsion polymerization using the name "Poval 205" manufactured by Kuraray Co., Ltd.) as an emulsifier,
A vinyl acetate resin-based emulsion (A1) containing an ethylene / vinyl acetate / acrylic acid copolymer having a nonvolatile content of 56%, a viscosity of 200 mPa · s, and an acid value of resin solid content of 16 mgKOH / g was obtained.

[Vinyl acetate resin emulsion (A2)
Production Example] Ethylene / vinyl acetate copolymer emulsion having a nonvolatile content of 55% and a viscosity of 250 mPa · s (trade name “SUMICA FLEX 455” manufactured by Sumitomo Chemical Co., Ltd.) was used as a vinyl acetate resin-based emulsion (A2). . [Production Example of Oxazoline Group-Containing Polymer (B1)] In a flask equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, a thermometer, and a dropping funnel, isopropyl alcohol 92.1 was added.
And 365.5 parts of deionized water, and heated to 80 ° C. while gently flowing nitrogen gas. There, 126 parts of methyl methacrylate prepared in advance, 2-
A monomer mixture consisting of 210 parts of isopropenyl-2-oxazoline, 84 parts of methoxypolyethylene glycol acrylate (trade name “Light Acrylate 130A” manufactured by Kyoeisha Chemical Co., Ltd.), and 2,2′-azobis (2 -Amidinopropane) dihydrochloride (trade name “V
-50 "(manufactured by Wako Pure Chemical Industries, Ltd.) and 21 parts of an initiator solution composed of 189 parts of isopropyl alcohol were respectively dropped from the dropping funnel over 2 hours. During the reaction, nitrogen gas was continuously blown, and the temperature in the flask was kept at 80 ° C ± 1 ° C. After maintaining the same temperature for 5 hours after the completion of the dropwise addition, the mixture was cooled and had a nonvolatile content of 40.4%, pH 8.7, and a viscosity of 570 mP
a · s aqueous solution of oxazoline group-containing polymer (B) (B
1) was obtained.

[Production Example of Oxazoline Group-Containing Polymer (B2)] A flask equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, a thermometer and a dropping funnel was charged with 782.4 of deionized water.
Part, and ammonium polyoxyethylene nonylphenyl ether sulfate (trade name “HYTENOL N
-08 "15% aqueous solution 128 of Daiichi Kogyo Seiyaku Co., Ltd.)
And pH 9 with an appropriate amount of 28% aqueous ammonia.
The temperature was adjusted to 0 and heated to 70 ° C. while gently flowing nitrogen gas. Thereto, 64 parts of 5% potassium persulfate was injected, and subsequently, a previously prepared monomer mixture consisting of 256 parts of butyl acrylate and 64 parts of 2-isopropenyl-2-oxazoline was added thereto. It was added dropwise over 3 hours. During the reaction, nitrogen gas was continuously blown, and the temperature in the flask was kept at 70 ° C ± 1 ° C. After maintaining the same temperature for 2 hours after the completion of the dropping, the internal temperature was raised to 80 ° C.
Stirring was continued for an hour to complete the reaction. Then cool down,
Non-volatile content 39.8%, pH 8.0, glass transition temperature -5
An aqueous dispersion (B) of the oxazoline group-containing polymer (B) at 0 ° C.
2) was obtained.

[Production Example of Oxazoline Group-Containing Polymer (B3)] 50 parts of butyl acrylate, 2-isopropenyl-
Except that a monomer mixture consisting of 30 parts of 2-oxazoline and 20 parts of styrene was used, a nonvolatile content of 39.25 was obtained in the same manner as in the production example of the oxazoline group-containing polymer (B2).
An aqueous dispersion (B3) of the oxazoline group-containing polymer (B) having 0%, pH 8.1, and a glass transition temperature of 0 ° C. was obtained.

[Production Example of Oxazoline Group-Containing Polymer (B4)] 25 parts of butyl acrylate, 2-isopropenyl-
Except that a monomer mixture consisting of 55 parts of 2-oxazoline and 20 parts of styrene was used, the nonvolatile content of the polymer was adjusted in the same manner as in the production example of the oxazoline group-containing polymer (B2).
An aqueous dispersion (B4) of the oxazoline group-containing polymer (B) having 0%, pH 8.0 and a glass transition temperature of 50 ° C. was obtained.

Example 1 To 100 parts (apparent weight) of a vinyl acetate resin-based emulsion (A1), 9.5 parts (apparent weight) of an aqueous solution of an oxazoline group-containing polymer (B1) were added, and an adhesive resin was prepared. A composition was obtained. Then, the adhesive resin composition was uniformly applied to a 0.2 mm soft vinyl chloride sheet using a bar coater so as to be 67 g / m ^2, and a 4 mm thick JAS was applied to the resin composition application surface.
After laminating one kind of birch plywood, 20 ° C, pressure 800
Pressing was performed at kg / m ² for 24 hours. Furthermore, after decompression, it was cured at 20 ° C. for one week to obtain a decorative board sample.
Various performances were evaluated by the following methods using the obtained decorative board sample and the adhesive resin composition. Table 1 shows the results
Shown in <Evaluation method> (1) Normal peel test The obtained decorative board was cut into a 25 mm width, and JIS-K-685 at an atmosphere of 20 ° C and a peel speed of 200 mm / min.
A 180 ° peel test was performed in the same manner as in Example 4.

(2) Water Resistance Peeling Test The obtained decorative board was cut into a width of 25 mm, immersed in water at 20 ° C. for 24 hours, and immediately dried without drying.
In an atmosphere of 0 ° C., at a peeling speed of 200 mm / min, JIS
A 180 ° peel test was performed by a method according to -K-6854. (3) Viscosity stability over time After mixing the vinyl acetate resin emulsion and the aqueous solution or aqueous dispersion of the oxazoline group-containing polymer, the mixture was allowed to stand for 1 week in an atmosphere of 50 ° C. I asked.

[Examples 2 to 6] One of the aqueous dispersions (B2), (B3) and (B4) of the oxazoline group-containing polymer was added to the vinyl acetate resin emulsion (A1) or (A2). Add the amount (apparent weight) shown in 1
An adhesive resin composition was obtained, and a decorative board sample was obtained in the same manner as in Example 1. Various performances were evaluated in the same manner as in Example 1 using the obtained decorative board and the adhesive resin composition. Table 1 shows the results.

[Examples 7 and 8] The adhesive resin compositions obtained in Examples 1 and 2 were used, and instead of a soft vinyl chloride sheet as an adhesive substrate, an OPP film (trade name “Pyrene” Toyobo) was used. A decorative board sample was obtained in the same manner as in Example 1 except that the above-mentioned method was used.
The untreated surface of the corona discharge treatment was used for the OPP film. Various performances were evaluated in the same manner as in Example 1 using the obtained decorative board sample and the adhesive resin composition. Table 1 shows the results.

Comparative Examples 1 and 2 Each of the vinyl acetate resin emulsions (A1) and (A2) was used alone as an adhesive resin composition. Then, a decorative board sample was obtained in the same manner as in Example 1 using each adhesive resin composition. Various performances were evaluated in the same manner as in Example 1 using the obtained decorative board sample and the adhesive resin composition. Table 2 shows the results.

Comparative Example 3 Instead of the oxazoline group-containing polymer (B), a polyisocyanate crosslinking agent (trade name "Aquanate 110" manufactured by Nippon Polyurethane Co., Ltd.)
Was used in the same manner as in Example 1 except that 10 parts (apparent weight) were used to obtain an adhesive resin composition. A decorative board sample was obtained in the same manner as in Example 1 using this adhesive resin composition. Various performances were evaluated in the same manner as in Example 1 using the obtained decorative board sample and the adhesive resin composition. Table 2 shows the results.

Comparative Example 4 Using the adhesive resin composition obtained in Comparative Example 1, an OPP film (Pyrene, Toyobo Co., Ltd.) was used instead of a soft vinyl chloride sheet as an adhesive base material.
Except for the use of Comparative Example 1, a decorative board sample was obtained. The untreated surface of the corona discharge treatment was used for the OPP film. Various performances were evaluated in the same manner as in Example 1 using the obtained decorative board sample and the adhesive resin composition. Table 2 shows the results.

[0054]

[Table 1]

[0055]

[Table 2]

As is clear from Table 1, the adhesive resin compositions obtained in Examples 1 to 8 were excellent in both the normal state and the water-resistant adhesive strength in a 180 ° peel test, and showed a vinyl chloride base material or a polyolefin base. In addition to exhibiting excellent adhesive strength to the material, it had good one-pack stability. On the other hand, as is clear from Table 2, the adhesive resin compositions obtained in Comparative Examples 1 and 2 are vinyl acetate resin emulsions (A1) or (A2) alone. Was extremely low in water-resistant adhesive strength. In addition, the adhesive resin composition obtained in Comparative Example 3 had a very poor one-pack stability because a polyisocyanate-based crosslinking agent was used instead of the oxazoline group-containing polymer. Further, from Comparative Example 4, the adhesiveness to the OPP film was also higher in the 180 ° peel test when the vinyl acetate resin-based emulsion (A1) was used alone than in the case where the oxazoline group-containing polymer was used. It is clear that the normal and water-resistant adhesive strength is very poor.

[0057]

According to the present invention, it is possible to provide an adhesive resin composition having good normal state and water-resistant adhesive strength and also having excellent one-pack stability.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4F100 AH02G AH03G AH07G AK01B AK04 AK15 AK31G AK31K AK62G AL05G AP00 AS00A BA02 CB00 DJ01A JB07 JB16B JK06 JL11 JM01G 4J040 DE021 DE031 LA03 JA07 MB07

Claims (7)

[Claims] 1. A vinyl acetate resin emulsion (A),
An adhesive resin composition comprising, as an essential component, an oxazoline group-containing polymer (B). 2. The vinyl acetate resin emulsion (A)
The adhesive resin composition according to claim 1, wherein the main component is an ethylene-vinyl acetate copolymer. 3. The vinyl acetate resin emulsion (A)
The adhesive resin composition according to claim 1, wherein the resin composition contains a carboxyl group. 4. The compounding amount of the oxazoline group-containing polymer (B) is 1 to 50 parts by weight based on 100 parts by weight of the vinyl acetate resin emulsion (A) on a solid content basis.
The adhesive resin composition according to any one of claims 1 to 3. 5. An adhesive used for bonding a porous substrate and a thermoplastic resin substrate, comprising an adhesive resin composition according to any one of claims 1 to 4. ,
adhesive. 6. A laminate comprising a porous substrate and a thermoplastic resin substrate bonded via the adhesive resin composition according to any one of claims 1 to 4. 7. An adhesive substrate to which the adhesive resin composition according to claim 1 is applied.