JPH11193372A - Emulsion composition for paper bonding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive compsn. which exhibits a good balance between the adhesive strength just after lamination and the heat resistance after curing in a process for producing printed decorative sheets, does not leave behind formaldehyde. and can eliminate the troublesomeness accompanying two-component systems. SOLUTION: 100 pts.wt. (solid basis) emulsion prepd. by the emulsion polymn. of 0.5-10 wt.% free-radical-polymerizable monomer having a carboxyl group, 1-15 wt.% free-radical-polymerizable monomer having a nitrile group. and 75-98.5 wt.% other free-radical-polymerizable monomer is compounded with 0.1-10 mmol of a polyvalent metal ion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an emulsion composition used for bonding paper and wood materials, and more particularly, to a paper-based decorative sheet made of plywood, MDF, particle board, etc. The present invention relates to an emulsion composition used for a decorative printed board manufactured by bonding the same. More specifically, the present invention relates to an emulsion composition having excellent adhesiveness immediately after laminating a decorative sheet and plywood, MDF, particle board, and the like, and high adhesive strength after curing and heat resistance.

[0002]

2. Description of the Related Art Printed decorative boards are generally made by bonding a paper decorative sheet to plywood, MDF, particle board or the like. Conventionally, a vinyl acetate adhesive or a combination of a thermoplastic emulsion and a thermosetting resin is used for the bonding. Printed decorative boards may be exposed to high temperatures during use, and adhesives have recently been required to have high heat resistance. However, the vinyl acetate adhesive has insufficient heat resistance, and the adhesive strength immediately after bonding is also insufficient. Here, the adhesive force immediately after bonding refers to the adhesive force immediately after the adhesive is applied to a paper decorative sheet or plywood, MDF, particle board, etc., dried, and then bonded. With a vinyl acetate adhesive, the adhesive strength is insufficient and the range of drying conditions is narrow, so that it is practically difficult to use the adhesive. Further, in combination with a thermosetting resin, there is a trouble that a two-liquid mixture system is used, and there is a problem that formaldehyde remains.

On the other hand, Japanese Patent Application Laid-Open No. Hei 6-330017 discloses a technique using a modified amino resin in combination with an isocyanate compound, but the above problem has not been solved because an amino resin is used. . Japanese Patent Application Laid-Open No. 8-157799 discloses an emulsion adhesive as a PVC wrapping adhesive. However, this technique does not have sufficient adhesiveness immediately after bonding, which is highly required for paper, and Since there is no cross-linking, it is inevitable that the resin adheres to the blade used in cutting after lamination curing.

[0004]

DISCLOSURE OF THE INVENTION The present invention relates to an adhesive suitable for producing a printed decorative board made by bonding paper and a woody material, etc., to provide an adhesive force immediately after lamination and a heat resistance after curing. It is an object of the present invention to balance formability, eliminate the residual formaldehyde, and solve the inconvenience of two liquids, and also solve the adhesion of resin to the blade even in cutting performed after lamination curing. It is to be.

[0005] In the bonding between paper and paper decorative sheet and plywood, MDF, particle board, etc., the mutual bonding surface is rough and relatively hydrophilic. Therefore, in addition to the above-mentioned problems, the emulsion composition of the present invention has a filling property capable of filling the unevenness of the rough surface and filling the unevenness, and an adhesive force after drying even on a relatively hydrophilic surface. It is required to have adhesiveness that can maintain the above. Further, the printed decorative board manufactured by using the emulsion composition of the present invention may be subjected to a condition in which a temperature is applied during use, so that the emulsion composition has heat resistance such that the adhesive strength is not reduced even by heating. Required.

An object of the present invention is to propose an emulsion composition that can satisfy these various required properties.

[0007]

Means for Solving the Problems The present inventors have found that the above problems can be solved by a combination of a specific acrylic emulsion and a polyvalent metal ion, and have reached the present invention. That is, the present invention relates to (A) 0.5 to 10% by weight of a radical polymerizable monomer having a carboxyl group, 1 to 15% by weight of a radical polymerizable monomer having a nitrile group, and other radical polymerizable monomers. Emulsion 1 obtained by emulsion polymerization of a mixture containing 75 to 98.5% by weight of a monomer
This is an emulsion composition for paper bonding in which (B) 0.1 to 10 mmol of a polyvalent metal ion is blended with respect to 00 parts by weight (in terms of solid content).

Hereinafter, the present invention will be described in detail. The radically polymerizable monomer having a carboxyl group used for producing the emulsion of the component (A) of the present invention is defined as having at least one carboxyl group and having one radically polymerizable double bond.
Or more. Examples of the radical polymerizable monomer having a carboxyl group include, for example, acrylic acid, monovalent carboxylic acid such as methacrylic acid, itaconic acid, fumaric acid, a polycarboxylic acid such as maleic acid, or a polycarboxylic acid. Examples include partially esterified compounds. One or two or more of these radically polymerizable monomers having a carboxyl group can be used. Preferably, acrylic acid, methacrylic acid and itaconic acid are used.

The amount of the radical polymerizable monomer having a carboxyl group is 0.5 to 10% by weight, preferably 0.1 to 10% by weight.
5 to 7% by weight, heat resistance is exhibited at 0.5% by weight or more, and adhesive strength immediately after lamination is exhibited at 15% by weight or less. The radically polymerizable monomer having a nitrile group used for producing the emulsion of the component (A) of the present invention is a monomer having at least one nitrile group and at least one radically polymerizable double bond. is there. For example, acrylonitrile, methacrylonitrile, alkyl cyanide and the like can be mentioned. One or more of these polymerizable monomers having a nitrile group may be used. Preferably, it is acrylonitrile or methacrylonitrile.

The amount of the radical polymerizable monomer having a nitrile group is 1 to 15% by weight, preferably 4 to 10% by weight.
When the content is 1% by weight or more, the toughness of adhesion is exhibited, and when the content is 15% by weight or less, the adhesive strength immediately after bonding is sufficient. Other radically polymerizable monomers used for producing the emulsion of the component (A) of the present invention include aromatic unsaturated compounds and α, β-unsaturated monocarboxylic acid alkyl esters. Examples of the aromatic unsaturated compound include styrene, α-methylstyrene, and vinyl toluene. Examples of the alkyl ester of an α, β-unsaturated monocarboxylic acid include an alkyl ester of acrylic acid or methacrylic acid. Alkyl esters of acrylic or methacrylic acid include methyl acrylate,
Ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, isobutyl acrylate, hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl acrylate, butyl methacrylate, isobutyl methacrylate, hexyl methacrylate, Examples thereof include cyclohexyl methacrylate, 2-ethylhexyl methacrylate, and lauryl methacrylate.

[0011] Radical polymerizable monomers other than those described above may be combined as necessary. For example, amide group-containing monomers such as acrylamide, methacrylamide, N,
N-methylenebisacrylamide, diacetone acrylamide, maleic amide, maleimide, etc., and a methylol group-containing monomer, for example, N-methylol acrylamide, N-methylol methacrylamide, dimethylol acrylamide, dimethylol methacrylamide, etc., an alkoxymethyl group-containing monomer, Epoxy group-containing monomers such as N-methoxymethylacrylamide, N-methoxymethylmethacrylamide, N-butoxymethylacrylamide, N-butoxymethylmethacrylamide,
For example, glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, methyl glycidyl acrylate, methyl glycidyl methacrylate and the like, hydroxyl group-containing monomers, for example, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate,
Polyfunctional monomers such as hydroxypropyl acrylate, hydroxypropyl methacrylate, polyethylene glycol acrylate, polyethylene glycol methacrylate, and the like, for example, divinylbenzene, polyoxyethylene diacrylate, polyoxyethylene dimethacrylate, polyoxypropylene diacrylate, polyoxypropylene dimethacrylate, Mono- or diester monomers of α, β-ethylenically unsaturated dicarboxylic acids, such as butanediol diacrylate, butanediol dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol tetraacrylate, and pentaerythritol tetramethacrylate, such as Mono or dibutyl maleate, fumaric acid Mono- or dioctyl and the like, vinyl ester monomers such as vinyl acetate, vinyl propionate and olefins such as butadiene, isoprene and chlorine-containing vinyl monomers such as vinyl chloride, vinylidene chloride and chloroprene can be exemplified.

The other radically polymerizable monomers may be one kind or a mixture of two or more kinds. Preferably, a combination of an aromatic unsaturated compound, an alkyl ester of α, β-unsaturated monocarboxylic acid, a methylol group-containing monomer, and an alkoxymethyl group-containing monomer is preferred. More preferably, the aromatic unsaturated compound includes styrene, and the alkyl ester of α, β-unsaturated monocarboxylic acid includes ethyl acrylate, butyl acrylate,
-Ethylhexyl acrylate and methyl methacrylate; and methylol group-containing monomers and alkoxymethyl group-containing monomers include N-methylolacrylamide and N-methoxymethylacrylamide.

The amount of other radically polymerizable monomer used is 75 to 98.5% by weight, preferably 83 to 95.
5% by weight. The emulsion of the component (A) of the paper bonding emulsion composition of the present invention can be produced by a conventionally known emulsion polymerization method. That is, emulsion polymerization is performed in the presence of a radical polymerizable monomer, a radical polymerization initiator, water, and a surfactant. For example, a plurality of radically polymerizable monomers are uniformly dissolved, and a surfactant, a dispersant, a protective colloid, a water-soluble polymer, etc., water and a radical polymerization initiator are added to form an emulsion dispersion, and then polymerized. Method. Also the method of adding the polymerization initiator may be added together with the emulsified dispersion or may be added separately,
Further, a radical polymerizable monomer mixture, a surfactant, an initiator and the like may be separately added.

Surfactants that can be used in emulsion polymerization include ionic and nonionic surfactants, and ionic surfactants include anionic, cationic and amphoteric surfactants. Examples of the anionic surfactant include a carboxylic acid type, a sulfate ester type, a sulfonic acid type, a phosphate ester type, and the like.Examples of the carboxylic acid type include a fatty acid soap and a naphthenic acid soap. Examples thereof include long-chain alcohol sulfate, polyoxyethylene alkyl phenyl ether sulfate, fatty acid monoglyceride sulfate, fatty acid monoalkanolamide sulfate, and the like.Examples of the sulfonic acid type include alkanesulfonic acid salts and α-sulfofatty acid salts. , Dialkyl sulfosuccinate, polyoxyethylene alkyl phenyl ether sulfonate, alkylbenzene sulfonate, formalin condensed naphthalene sulfonate, and the like. Examples of the phosphate ester type include polyoxyethylene alkyl E alkenyl ether phosphate salts, polyoxyethylene alkyl ether phosphate salts, and the like.

Examples of the cationic surfactant include a quaternary ammonium type, an aliphatic amine type and a heterocyclic amine type. Examples of the quaternary ammonium type include a long-chain primary amine salt and dialkyldimethylammonium. salt,
Long-chain tertiary amine salts, alkyltrimethylammonium salts, alkylpyridinium salts and the like are mentioned, examples of the aliphatic amine type include polyoxyethylene alkylamines, and examples of the heterocyclic amine type include alkylimidazoline and the like. Can be

Examples of the amphoteric surfactant include N-alkylamino acid type and imidazoline type. Examples of the N-alkylamino acid type include N-alkyl-β-aminopropionate and N-alkyl-β-imino. Examples include dipropionate salts, and the imidazoline type includes, for example, 2-alkylimidazoline derivatives.
As the nonionic surfactant, for example, ether type,
Ester type, alkanolamide type and the like, and examples of the ether type include polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether,
Polyoxyethylene alkyl thioethers and the like, and examples of the ester type include polyoxyethylene monofatty acid ester, polyoxyethylene difatty acid ester, polyoxyethylene propylene glycol fatty acid ester, polyoxyethylene sorbitan monofatty acid ester, glycerin monofatty acid ester, Examples include sucrose fatty acid esters, and examples of the alkanolamide type include fatty acid diethanolamide and polyoxyethylene alkylamide.

Preferred are nonionic and anionic surfactants. In addition to the non-reactive surfactants described above, a reactive surfactant may be used in combination or alone. The reactive surfactant has a radical polymerizable double bond in one molecule and has one or more functional groups selected from sulfonic acid groups, sulfonic acid ester groups, sulfonic acid groups, sulfonic acid ester bases, or It has a radical polymerizable double bond functional group in one molecule and has polyoxyethylene, polyoxypropylene, polyoxyethylene polyoxypropylene composite type alkyl ether or alcohol. Here, the salt refers to a sodium salt, a potassium salt, and an ammonium salt.

Examples of the dispersant, protective colloid, and water-soluble polymer include polyphosphate, polyacrylate, styrene-maleic acid copolymer salt, styrene-acrylic acid copolymer salt, and styrene-methacrylic acid copolymer. Coalescent salts, water-soluble acrylate copolymer salts, water-soluble methacrylate copolymer salts, polyvinyl alcohol, polyacrylamide, polymethacrylamide, polyacrylamide copolymer, polymethacrylamide copolymer, and the like.

As the polymerization initiator, water-soluble and oil-soluble polymerization initiators can be used. As the water-soluble polymerization initiator,
For example, persulfates, peroxides, water-soluble azobis compounds,
A peroxide-reducing agent redox system and the like are exemplified. Examples of the persulfate include ammonium persulfate, potassium persulfate, and sodium persulfate, and examples of the peroxide include hydrogen peroxide and t-butylhydrogen. Peroxide, t-butylperoxymaleic acid, and succinic peroxide are exemplified. Examples of the water-soluble azobis compound include 2,2′-azobis (N-hydroxyethylisobutylamide) and 2,2′-azobis (2- Amidinopropane) dihydrochloride, 4,4′-azobis (4-cyanopentanoic acid) and the like. As the redox system of the peroxide-reducing agent, for example, sodium sulfooxylate formaldehyde, Sodium bisulfite, sodium thiosulfate, sodium hydroxymethanesulfinate, L-asco Bottles acids, and their salts, cuprous salts, addition of a reducing agent such as ferrous salts.

Examples of the oil-soluble polymerization initiator include peroxides and oil-soluble azobis compounds. Examples of the peroxide include dibutyl peroxide, benzoyl peroxide, lauroyl peroxide, cumene hydroperoxide. And the like. Examples of the oil-soluble azobis compound include, for example, 2,2 ′
-Azobisisobutyronitrile, 2,2'-azobis-
2-methylbutyronitrile, 2,2'-azobis-2,
4-dimethylvaleronitrile and the like.

In the emulsion polymerization of the emulsion of the component (A) of the emulsion composition for paper adhesion of the present invention, if necessary, the pH of sodium hydrogen phosphate, sodium hydrogen carbonate or the like may be adjusted.
Before, during, and during the emulsion polymerization, a regulator, t-dodecyl mercaptan, a molecular weight regulator such as n-dodecyl mercaptan or a low molecular weight halogen compound, a chelating agent, a plasticizer, an organic solvent, etc.
It can be added in any of the later cases.

The polymerization temperature is, for example, from 0 to 150 ° C., especially from 30.
The temperature is preferably in the range of from 90 ° C to 90 ° C, and the reaction is carried out in an inert atmosphere under normal pressure or, if necessary, under pressure. The glass transition temperature of the emulsion of the component (A) of the paper bonding emulsion composition of the present invention is preferably from -50C to 20C. -50 ° C
As described above, heat resistance is exhibited, and at 20 ° C. or lower, there is no problem in adhesiveness immediately after bonding. More preferably, -40C
0 ° C.

The particle size of the emulsion is not particularly limited, but is preferably 50 to 1000 nm. More preferably, it is 80 to 500 nm. The emulsion used in the present invention may be a core-shell type emulsion. In the case of the core shell type, a difference in Tg, a difference in crosslinking, and the like may be provided between the core and the shell.

Examples of the polyvalent metal ion which is the component (B) of the paper bonding emulsion composition of the present invention include divalent to pentavalent metal ions. For example, zinc, iron, nickel,
Examples include copper, titanium, magnesium, calcium, barium, aluminum, zirconium, cadmium, nickel, and lead. Preferred are zinc, zirconium and calcium. These may be used alone or in a mixture of two or more.

The polyvalent metal ion may be added at the beginning of polymerization, during polymerization, or after polymerization. Preferably, after polymerization. The polyvalent metal ion may be used in any form such as an oxide, a hydrate, a salt, and a complex. When the polyvalent metal ion is in the form of a salt, the ion to be paired with the polyvalent metal ion may be an organic ion, an inorganic ion, or a form containing both. When the ion to be paired with the polyvalent metal ion is an organic ion, the polyvalent metal ion is used in the form of, for example, formate, acetate, oxalate and the like. When the ion to be paired with the polyvalent metal ion is an inorganic ion, the polyvalent metal ion is used in the form of, for example, chloride, sulfate, nitrate, nitrite, carbonate and the like.

When the polyvalent metal ion is in the form of a complex,
For example, combinations with the above-mentioned salts can be mentioned, and specific examples include ammonium complexes, ammine complexes, and polyvalent carboxylic acid complexes. For example, Japanese Patent Application Laid-Open No. 62-250078
Aqueous zinc carbonate solution, aqueous solution of zirconium carbonate, aqueous solution of zinc acetate, aqueous solution of zinc acrylate, aqueous solution of zinc glycine, aqueous solution of zinc glycine, aqueous solution of zinc malate and the like as described in Japanese Patent Publication No. Particularly, an aqueous solution of zinc carbonate and an aqueous solution of ammonium zirconium carbonate are practically preferable.

When the polyvalent metal ion is added, it can be added as an aqueous solution, a solution of an organic solvent, an emulsion, a paste, a slurry of powder, or the like. In the present invention,
The blending ratio of the emulsion of the component (A) to the polyvalent metal ion of the component (B) was determined as the emulsion 100 in terms of solid content.
The polyvalent metal ion is used in an amount of 0.1 to 10 mmol, preferably 0.5 to 8 mmol, per part by weight.
When (B) is 0.1 mmol or more, heat resistance is exhibited, and when it is 10 mmol or less, the adhesiveness immediately after bonding is sufficient.

A paper decorative sheet using the emulsion composition of the present invention is used for a printed decorative board, for example, Wood Industry, Vol 47, No. 12 (199).
There is no particular limitation on thin paper decorative paper described on page 583 of 2) or impregnated paper decorative paper in which a base paper is impregnated with a polymer. The method of using the emulsion composition of the present invention is not particularly limited. It may be used after thickening the emulsion composition with a thickener or the like,
It may be used after mixing inorganic and organic fillers.

There is no particular limitation on the method of sticking. For example, an adhesive is applied to plywood, MDF, particle board, etc.
Thereafter, a paper decorative sheet may be attached, or an adhesive may be applied to the paper decorative sheet, and thereafter, plywood, MDF, particle board, or the like may be attached. An adhesive may be applied to both plywood, MDF, particle board, etc., and a paper decorative sheet, and then both may be attached.

The drying conditions after the application of the emulsion composition are not particularly limited. What is necessary is just to heat or leave at normal temperature. Lamination of the paper composition sheet and plywood after drying the emulsion composition may also be performed using a press, a roll, or the like,
There is no particular limitation. If necessary, other emulsions may be added to the component (A) of the emulsion composition of the present invention. For example, a vinegar emulsion, an ethylene vinegar emulsion, a styrene-butadiene emulsion, a urethane emulsion, a chloroprene emulsion, and an acrylonitrile-butadiene emulsion are exemplified.

Further, the emulsion composition contains a bactericide,
Even if preservatives, defoamers, plasticizers, flow regulators, thickeners, pH regulators, surfactants, dyes, coloring pigments, various coupling agents, wax emulsions, inorganic fillers, organic fillers, etc. are added. good. If necessary, an amino resin such as a melamine resin, a urea resin, or a benzoguanamine resin, or an isocyanate resin or an epoxy compound may be added to the emulsion composition of the present invention.

The emulsion composition of the present invention can be used not only for paper decorative sheets, but also for PVC decorative sheets, wallpapers, filters, building interior / exterior materials, automobile interior materials, agricultural and medical adhesives, etc. Can be used.

[0033]

Embodiments of the present invention will be described below. Unless otherwise specified, figures are based on weight. The methods for evaluating various physical properties in the present invention are as follows. (1) Paste leaving one end of the bond strength basis weight of 60 g / m ² of titanium sheet immediately after the emulsion composition 60 g / m ² is applied. Then, it is left in a dryer at 40 ° C. for 60 seconds. Next, a commercially available MDF (9 mm thick)
), The surface of the titanium paper coated with the emulsion composition is overlapped, and a 5 kg roller is reciprocated three times.

Immediately thereafter, hold the unbonded end of the titanium paper and slowly pull it apart. The bonded surface is observed and evaluated according to the following evaluation criteria. ○ The above is judged to be acceptable. ◎ There is resistance, and cohesive failure of the emulsion composition or fracture of the titanium paper portion occurs in 90% or more of the total bonding area. ○ There is resistance, and cohesive failure of the emulsion composition or breakdown of the titanium paper portion occurs in less than 90% to 40% or more of the total adhesive area.

X: Cohesive failure of the emulsion composition or the titanium paper portion occurs when the resistance is less than 40% of the total adhesive area, or the emulsion composition is peeled without resistance and does not cause cohesive failure of the emulsion composition. (2) Adhesive strength after curing After preparing the same material as the one for evaluating the adhesive strength immediately after pasting, leave it at 20 ° C. for 5 days and cure. afterwards,
Hold the unbonded end of the titanium paper and slowly pull it apart.
The bonded surface is observed and evaluated according to the following evaluation criteria. ○ The above is judged to be acceptable.

◎ The titanium paper part is broken at 90% or more of the total bonding area ○ The titanium paper part is broken at less than 90% of the total bonding area × interface between titanium paper and emulsion composition, or M
Peeling off at the interface between the DF and the emulsion composition, and no destruction of the titanium paper portion occurs. (3) Heat resistance after curing After preparing the same material as for the evaluation of the adhesive strength immediately after pasting, leave it at 20 ° C for 5 days and cure it, then make one short side of the titanium paper an unbonded end. Then, cut out with a cutter so that the bonding area becomes 25 mm wide and 10 cm long. A 200 g weight is attached to one end of the unbonded portion in the direction of 180 ° and left in a dryer at 60 ° C for 24 hours. After 24 hours, the state of the bonded product is observed and evaluated according to the following evaluation criteria. ○ The above is judged to be acceptable.

◎ No peeling of the bonding surface. ○ The adhesive surface was peeled, but the length was less than 5 cm. Poor: The peel length of the bonding surface was 5 cm or more, or the titanium paper was all peeled off and the weight dropped.

[0038]

[Production Examples 1 to 9] Production examples of emulsions 1 to 9 are shown below.
To 1000 parts of the radical polymerizable monomer shown in Table 1, 30 parts of a 25% aqueous solution of sodium alkyl allyl sulfosuccinate (trade name: Eleminol JS-2, manufactured by Sanyo Chemical Co., Ltd.), polyoxyethylene nonyl 30 parts of a 25% aqueous solution of sodium phenyl ether sulfate (trade name: Emar NC, manufactured by Kao Corporation), 2 parts of ammonium persulfate, and 400 parts of distilled water are added, and the mixture is stirred with a homomixer to prepare a pre-emulsion. Produced.

Separately, add 500 distilled water to a flask equipped with a stirrer.
And 4 parts of an aqueous solution adjusted to 25% of Emal NC, the temperature was raised to 80 ° C., and 1 part of ammonium persulfate was added to 50 parts of water.
Add the solution dissolved in the part. To this, the pre-emulsion is continuously dropped over 4 hours. Thereafter, stirring was continued at the same temperature for 3 hours. Then, cool to 30 ° C or less, and then
Filtration was performed using a 0 mesh wire mesh. After filtration, 25
The pH was adjusted to 7 with aqueous ammonia having a concentration of 7%, and water was added to adjust the solid content to 48%.

The viscosity of the emulsion after the emulsion polymerization and the Tg calculated from the total radical polymerizable monomers are also shown in Table 1.

[0041]

Examples 1 to 11 Emulsions 1 obtained in Production Examples 1 to 7
7 to 100 parts (each containing water) and 2 parts of a 25% aqueous solution of polyoxyethylene nonylphenyl ether (trade name: Emulgen 950, manufactured by Kao Corporation) (each containing water). Is added. Thereafter, an aqueous solution of zinc carbonate (6.4% in terms of zinc) or a 10% aqueous solution of calcium chloride was stirred and mixed at a ratio of 2 to 10 parts by weight (a numerical value including water) shown in Table 2 to form an emulsion composition. I got something.

The above-described performance evaluation was performed using these emulsion compositions. Table 3 shows the results. In addition, when the pasted material of a predetermined size was cut out with a cutter in order to evaluate the heat resistance after curing, no resin adhered to the blade of the cutter, and the cutter blade could be cut out without any problem.

[0043]

Comparative Examples 1 to 4 Emulsions 2, 8, and 9 obtained in Production Examples 2, 8, and 9 were used to prepare emulsion compositions according to the formulations shown in Table 4. In addition, the numerical values of the amounts of the emulsion, the emulgen 950, and the aqueous solution of zinc ammonium carbonate shown in Table 4 are all numerical values including water. Next, performance evaluation was performed in the same manner as in the examples. Table 5 shows the results.

[0044]

Comparative Example 5 8 parts of methacrylic acid, 43 parts of 2-ethylhexyl acrylate, 27 parts of butyl acrylate, 15 parts of methyl methacrylate, 7 parts of vinyl acetate, 0.03 part of lauryl mercaptan, 35.5 parts of water, Levenol WZ
Two parts (polyoxyethylene alkyl ether sodium sulfate, manufactured by Kao) were emulsified with a homomixer to prepare a mixed emulsion.

Next, 15 parts of ion-exchanged water was charged into a flask with a stirrer, and the temperature was raised to 80 ° C. To this, the above mixed emulsion was precharged at 5%, and at the same time, 0.6 part of a 5% aqueous solution of ammonium persulfate was added to start emulsion polymerization. Ten minutes after the start of the emulsion polymerization, the remaining mixed emulsion and 5.4 parts of a 5% aqueous solution of ammonium persulfate were added dropwise over 3 hours. During this time, the temperature inside the flask was kept at 80 ° C. After completion of the dropwise addition, the inside of the flask was kept at 80 ° C. for 2 hours.
After the completion of the reaction, the reaction mixture is cooled to 30 ° C. or lower, and the ammonia water is added to 0.1%.
Emulsion 8 was obtained by adding 5 parts. To 100 parts by weight of this emulsion (in terms of solid content), 10 parts (in terms of solid content) of urethane emulsion (Superflex 750, solid content 40%, manufactured by Daiichi Kogyo Seiyaku) were added and mixed.
The solid content of the emulsion was 60% and the pH was 5.4.

Using this emulsion, the adhesive strength immediately after the application was measured, and the result was x based on the same evaluation criteria. In addition, for the evaluation of heat resistance after curing, cutting was performed with a cutter in the same manner as in the example, but the resin adhered to the blade of the cutter and cutting was not performed smoothly.

[0047]

[Table 1]

[0048]

[Table 2]

[0049]

[Table 3]

[0050]

[Table 4]

[0051]

[Table 5]

[0052]

According to the present invention, when paper and a wooden material are bonded, a balance between the adhesive strength immediately after bonding and the heat resistance after curing can be achieved. Also, there is no residual formaldehyde,
In addition, the inconvenience of mixing and using the two liquids can be eliminated. In addition, it has a filling property that can fill in irregularities on rough surfaces such as paper and plywood surfaces to fill in irregularities, and has an adhesive force after drying even on relatively hydrophilic surfaces such as paper and plywood surfaces. It has the heat resistance that can be maintained and the adhesive strength does not decrease by heating. In addition, even when cutting with a cutter, cutting can be performed smoothly without resin adhering to the blade of the cutter.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08F 220: 06 220: 44)

Claims (1)

[Claims] (A) 0.5 to 10% by weight of a radical polymerizable monomer having a carboxyl group; 1 to 15% by weight of a radical polymerizable monomer having a nitrile group; (B) 0.1 to 10 parts by weight of a polyvalent metal ion (B) per 100 parts by weight (solid content) of an emulsion obtained by emulsion polymerization of a mixture containing 75 to 98.5% by weight of a monomer.
Emulsion composition for paper bonding containing mmol.