WO2013099801A1 - Aqueous adhesive - Google Patents

Abstract

The purpose of the present invention is to provide an aqueous adhesive which has excellent adhesiveness between bodies to be adhered. This aqueous adhesive contains at least two types of compositionally different ethylene-(meth)acrylate anhydride maleic acid copolymers, and this aqueous adhesive ideally further contains a surfactant, a basic compound and/or an adhesive resin.

Description

Water-based adhesive

The present invention relates to a water-based adhesive.

In general, various resins are contained in the water-based adhesive, and in order to impart or exhibit the characteristics required for the use of the water-based adhesive, studies on the type of resin and the like have been made (non-patent) Reference 1).

Conventional water-based adhesives are not always satisfactory in terms of adhesion to various adherends.

The present invention includes the following inventions.
[1] An aqueous adhesive comprising at least two ethylene- (meth) acrylate-maleic anhydride copolymers having different compositions.
[2] The aqueous adhesive according to [1], further comprising a surfactant represented by the following formula (I).

(In the formula, X represents a hydrogen atom or —SO ₃ M (M is a hydrogen atom, NH ₄ or an alkali metal). N represents an integer of 1 to 3. m represents an integer of 1 to 100.)
[3] The aqueous adhesive according to [2], wherein the surfactant includes at least two of a surfactant in which X is a hydrogen atom and a surfactant in which X is —SO ₃ M.
[4] The aqueous adhesive according to [2] or [3], wherein —SO ₃ M in the surfactant is —SO ₃ NH ₄ .
[5] The surfactant is a surfactant represented by the formula (A) and a surfactant represented by the formula (B) in a weight ratio of 1 to 99:99 to 1, 5 to 95. : 95-5, 10-90: 90-10, 30: 70-90: 10, 40: 60-90: 10 or 50: 50-90: 10, any one of [2]-[4] The water-based adhesive described in 1.

(In the formula, m represents an integer of 1 to 100.)
[6] The surfactant contains 0.1 to 50 parts by weight, 0.1 to 20 parts by weight, or 0.1 to 10 parts by weight with respect to 100 parts by weight of the resin contained in the aqueous adhesive [2]. -The water-based adhesive according to any one of [5].
[7] The ethylene: (meth) acrylate-maleic anhydride copolymer has a molar ratio of structural units of ethylene: (meth) acrylate: maleic anhydride of 10 to 95:50 to 1: 0.01 to 10 The water-based adhesive according to any one of [1] to [6].
[8] The ethylene- (meth) acrylate-maleic anhydride copolymer is contained in two kinds in a weight ratio of 1:99 to 99: 1, according to any one of [1] to [7] Water based adhesive.
[9] The aqueous adhesive according to any one of [1] to [8], further containing a basic compound.
[10] The aqueous adhesive according to any one of [1] to [9], further containing an adhesive resin.
[11] The aqueous adhesive according to any one of [1] to [10], wherein the aqueous adhesive contains a dispersoid having a particle size (number basis) of 0.01 to 1.0 μm.
[12] The aqueous adhesive according to any one of [1] to [11], further comprising a polyurethane resin or a water-insoluble polyurethane resin.

[13] Further, it contains a terpene resin selected from the group consisting of terpene polymers, terpene phenols, β-pinene polymers, aromatic modified terpene polymers, α-pinene polymers, and terpene hydrogenated resins. 1] to [12] The water-based adhesive according to any one of [12].
[14] A terpene resin selected from the group consisting of a polyurethane resin and a terpene polymer, terpene phenol, β-pinene polymer, aromatic modified terpene polymer, α-pinene polymer, and terpene hydrogenated resin The water-based adhesive according to any one of [1] to [11].
[15] The aqueous adhesive according to any one of [1] to [11], further comprising a polyurethane resin and terpene phenol or a water-insoluble polyurethane resin and terpene phenol.
[16] The aqueous adhesive according to any one of [1] to [15], further containing an isocyanate.
[17] Further, it contains an isocyanate selected from the group consisting of diphenylmethane diisocyanate (MDI), tolylene diisocyanate (TDI), hexamethylene diisocyanate (HDI), xylene diisocyanate (XDI) and oligomers or polymers thereof [1]. -The water-based adhesive according to any one of [15].
[18] After an ethylene- (meth) acrylate-maleic anhydride copolymer is obtained by polymerization, the ethylene- (meth) acrylate-maleic anhydride copolymer is dispersed in an aqueous medium and then obtained by an emulsification method. The water-based adhesive according to any one of [1] to [17].

According to the present invention, an aqueous adhesive capable of firmly bonding various adherends can be provided.

The aqueous adhesive of the present invention contains at least two ethylene- (meth) acrylate-maleic anhydride copolymers having different compositions.

<Copolymer>
The copolymer contained in the aqueous adhesive of the present invention is at least two ethylene- (meth) acrylate-maleic anhydride copolymers having different compositions, saponified products or partially saponified products thereof.
In this specification, acrylic acid and methacrylic acid are collectively referred to as (meth) acrylic acid, and acrylate and methacrylate are collectively referred to as (meth) acrylate.
Also, the (meth) _acrylate, a _C 1 ~ C ₁₀ alkyl group, esters of (meth) acrylic acid such as hydroxyl group-containing _C 1 ~ C ₁₀ alkyl group.
(Meth) acrylate includes methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, glycidyl (meth) acrylate, 2-hydroxyethyl acrylate, ester of methacrylic acid and alcohol And the like. Of these, methyl (meth) acrylate and ethyl (meth) acrylate are preferred.

“The compositions are different from each other” means that the molar ratio of the structural units derived from ethylene, (meth) acrylate monomer, and maleic anhydride constituting the ethylene- (meth) acrylate-maleic anhydride copolymer is different. Alternatively, as described above, the structure of the structural unit derived from (meth) acrylate may be different, or both may be different. Further, the molar ratio of structural units derived from ethylene alone, (meth) acrylate alone or maleic anhydride alone may be different, or the molar ratio of structural units derived from two or more components may be different. Alternatively, the molar ratio of structural units derived from all components may be different.
The ethylene- (meth) acrylate-maleic anhydride copolymers having different compositions may be only two kinds or may contain three or more kinds.

The form of this copolymer may be any of random copolymerization, block copolymerization, graft copolymerization, and the like. Further, it may be a modified product of ethylene- (meth) acrylate copolymer with maleic anhydride.
The molar ratio of the structural units of the ethylene- (meth) acrylate-maleic anhydride copolymer is usually 10 to 95:50 to 1: 0.01 to 10, preferably 20 to 95:50 to 1: It is 0.01 to 10, more preferably 30 to 95:35 to 4:10 to 1.
Such an ethylene- (meth) acrylate-maleic anhydride copolymer can be adjusted to the above-described composition ratio by adjusting the amount of each monomer used relative to the total amount of the raw material monomers. it can.

When there are two types of ethylene- (meth) acrylate-maleic anhydride copolymers having different compositions contained in the aqueous adhesive, the weight ratio thereof is, for example, 1:99 to 99: 1, preferably 5:95 to 95: 5, more preferably 10:90 to 90:10.

The ethylene- (meth) acrylate-maleic anhydride copolymer can be produced by a method known in the art, such as a radical polymerization method. As a method for producing the modified product, after melting ethylene and (meth) acrylic acid, maleic anhydride is added and modified, and ethylene and (meth) acrylic acid are dissolved in a solvent such as toluene and xylene. Thereafter, a known method such as a method of modifying by adding maleic anhydride may be used. The structural unit derived from maleic anhydride may be one in which an anhydride group (—CO—O—CO—) is retained or may be ring-opened, and may be ring-opened from the one retained. Both of them may be contained.
Examples of commercially available ethylene- (meth) acrylate-maleic anhydride copolymers include BONDINE AX8390, BONDINE HX8290, BONDINE LX4110, BONDINE HX8140, BONDINE HX8210 OREVAC T9314, OREVAC T9318, and OREVAC K1811.

In the water-based adhesive of the present invention, the content of the ethylene- (meth) acrylate-maleic anhydride copolymer is, for example, that the stability of the water-based adhesive is maintained, the viscosity is kept moderate, and the good film-forming ability is maintained. Alternatively, from the viewpoint of developing good adhesiveness, it is preferably 1 to 60% by weight, more preferably 3 to 50% by weight, and further preferably 5 to 40% by weight with respect to the total amount of the aqueous adhesive. is there.

<Other resins>
The aqueous adhesive of the present invention may contain a resin other than at least two kinds of ethylene- (meth) acrylate-maleic anhydride copolymers having different compositions.
Examples of such resins include resins having structural units derived from α-olefins having 2 to 20 carbon atoms, polyolefin resins, acrylic resins (PMMA), polyvinyl chloride (PVC), polyvinylidene chloride, polystyrene ( PS), polyvinyl acetate (PVAc), polytetrafluoroethylene (PTFE), acrylonitrile butadiene styrene resin (ABS resin), AS resin and other polymers and copolymers, and modified polymers and modified products. . You may use these individually or in combination of 2 or more types.

Examples of the α-olefin having 2 to 20 carbon atoms include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene and 1-undecene. 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, vinylcyclohexane and the like. Preferably, ethylene, propylene, etc. are mentioned.

Examples of the copolymer containing a structural unit derived from an α-olefin having 2 to 20 carbon atoms include polyethylene (PE), high density polyethylene (HDPE), medium density polyethylene (MDPE), low density polyethylene (LDPE), polypropylene (PP And the like, or modified products thereof, such as ethylene-propylene copolymer, propylene-1-butene copolymer, ethylene-1-butene copolymer, ethylene-1-octene copolymer, ethylene- Α-olefin copolymers such as 1-hexene copolymer, ethylene-propylene-1-butene copolymer or modified products thereof, copolymers with copolymerizable monomers or modified products thereof, or two of these A mixture of the above is preferred. In a copolymer with a copolymerizable monomer, the copolymerizable monomer and α-olefin may be used alone or in combination of two or more. The form of the copolymer may be any of random copolymerization, block copolymerization, graft copolymerization, and the like. These may be those having a low molecular weight or a high molecular weight with a peroxide or the like.

Examples of the modified product of an α-olefin copolymer or a copolymer with a copolymerizable monomer include a modified product of an α, β-unsaturated carboxylic acid. In this case, the modification amount is usually 0.1 to 10% by weight, preferably 0.2 to 5% by weight, more preferably 0.2 to 4% by weight with respect to 100% by weight of the copolymer.
Examples of α, β-unsaturated carboxylic acids include α, β-unsaturated carboxylic acids (maleic acid, itaconic acid, citraconic acid, etc.), α, β-unsaturated carboxylic acid esters (methyl maleate, methyl itaconate) ), Α, β-unsaturated carboxylic anhydrides (maleic anhydride, itaconic anhydride, citraconic anhydride, etc.). These α, β-unsaturated carboxylic acids may be used in combination.

Such a modified product is a method in which an α-olefin copolymer or a copolymerizable monomer is melted and then modified by adding an α, β-unsaturated carboxylic acid or the like, an α-olefin copolymer Alternatively, it can be produced by a known method such as a method in which a copolymerizable monomer is dissolved in a solvent such as toluene or xylene and then modified by adding an α, β-unsaturated carboxylic acid or the like. In the case where the modified product contains a structural unit derived from an α, β-unsaturated carboxylic acid anhydride, even if the acid anhydride group (—CO—O—CO—) is retained, It may be the one that has been held and may contain both the retained one and the ring-opened one.

Examples of the copolymerizable monomer include unsaturated carboxylic acid or its anhydride, metal salt of α, β-unsaturated carboxylic acid, α, β-unsaturated carboxylic acid ester, vinyl ester, vinyl ester saponified product, cyclic olefin, Examples include vinyl aromatic compounds, polyene compounds (such as dienes), (meth) acrylonitrile, halogenated vinyls, and halogenated vinylidenes. You may use these individually or in combination of 2 or more types.

Examples of unsaturated carboxylic acids or anhydrides include acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, fumaric acid, crotonic acid, and unsaturated dicarboxylic acid half esters or half amides. Is mentioned. Of these, acrylic acid, methacrylic acid, maleic acid, and maleic anhydride are preferable, and acrylic acid and maleic anhydride are particularly preferable.
Examples of the metal salt of α, β-unsaturated carboxylic acid include sodium salt and magnesium salt of (meth) acrylic acid.
Examples of α, β-unsaturated carboxylic acid esters include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, glycidyl (meth) acrylate, 2-hydroxyethyl acrylate, Examples include esterified products of methacrylic acid and alcohol. Of these, methyl (meth) acrylate and ethyl (meth) acrylate are preferred.

Examples of vinyl esters include vinyl formate, vinyl acetate, vinyl propionate, vinyl pivalate, vinyl versatate, and the like. Of these, vinyl acetate is preferred.
Examples of the vinyl ester saponified product include vinyl alcohol obtained by saponifying vinyl ester with a basic compound or the like.

Examples of the cyclic olefin include norbornene, 5-methylnorbornene, 5-ethylnorbornene, 1,4,5,8-dimethano-1,2,3,4,4a, 5,8,8a-octahydronaphthalene, 1 , 2-dihydrodicyclopentadiene, 5-chloronorbornene, cyclopentene, cyclohexene, cycloheptene, vinylcyclohexane and the like.

Examples of the vinyl aromatic compound include styrene, α-methylstyrene, p-methylstyrene, vinylxylene, monochlorostyrene, dichlorostyrene, monobromostyrene, dibromostyrene, fluorostyrene, p-tert-butylstyrene, ethylstyrene, Examples include vinyl naphthalene.

Examples of polyene compounds include linear or branched aliphatic conjugated polyene compounds, alicyclic conjugated polyene compounds, aliphatic non-conjugated polyene compounds, alicyclic non-conjugated polyene compounds, and aromatic non-conjugated polyene compounds. Can be mentioned. These may have a substituent such as an alkoxy group, an aryl group, an aryloxy group, an aralkyl group, and an aralkyloxy group.

Examples of the aliphatic conjugated polyene compound include 1,3-butadiene, isoprene, 2-ethyl-1,3-butadiene, 2-propyl-1,3-butadiene, 2-isopropyl-1,3-butadiene, 2- Examples thereof include methyl-1,3-decadiene, 2,3-dimethyl-1,3-pentadiene, 2,3-dimethyl-1,3-octadiene, 2,3-dimethyl-1,3-decadiene and the like.

Examples of the alicyclic conjugated polyene compound include 2-methyl-1,3-cyclopentadiene, 2-methyl-1,3-cyclohexadiene, 2,3-dimethyl-1,3-cyclohexadiene, 2-chloro- Examples include 1,3-butadiene, 2-chloro-1,3-pentadiene, 2-chloro-1,3-cyclohexadiene and the like.

Examples of the aliphatic non-conjugated polyene compound include 1,4-hexadiene, 1,6-heptadiene, 1,6-octadiene, 1,9-decadiene, 3,3-dimethyl-1,4-hexadiene, and 5-ethyl. -1,4-heptadiene, 4-methyl-1,4-octadiene, 5-methyl-1,4-octadiene, 4-ethyl-1,4-octadiene, 4-methyl-1,4-nonadiene, 5-methyl 1,4-decadiene, 6-methyl-1,6-undecadiene, 4-ethylidene-12-methyl-1,11-pentadecadiene, and the like.

Examples of the alicyclic non-conjugated polyene compound include vinylcyclohexane, vinylcyclohexene, 5-vinyl-2-norbornene, 1,4-divinylcyclohexane, 1-isopropenyl-3-vinylcyclopentane, methyltetrahydroindene and the like. It is done.

Examples of the aromatic non-conjugated polyene compound include divinylbenzene and vinylisopropenylbenzene.

Specific examples of the copolymer of a monomer copolymerizable with an α-olefin include the following copolymers (i) to (vii).
(i) ethylene-vinyl acetate copolymer, saponified product or partially saponified product thereof (ii) ethylene- (meth) acrylic acid copolymer,
(iii) ethylene- (meth) acrylate copolymer such as ethylene-glycidyl (meth) acrylate copolymer, ethylene-methyl (meth) acrylate copolymer,
(iv) ethylene-alicyclic α-olefin copolymers such as ethylene-vinylcyclohexane,
(v) ethylene-vinyl acetate- (meth) acrylate copolymers such as ethylene-vinyl acetate copolymer-glycidyl (meth) acrylate, ethylene-vinyl acetate copolymer-methyl (meth) acrylate,
(vi) ethylene- (meth) acrylate- (meth) acrylate copolymers such as ethylene-glycidyl (meth) acrylate-methyl (meth) acrylate copolymer,
(vii) copolymers of these metal salts.

Furthermore, you may use resin which exhibits the function as an adhesive resin or a tackifier.
Examples of such resins include rosins, terpene resins, petroleum resins obtained by polymerizing petroleum fractions having 5 carbon atoms and hydrogenated resins, petroleum resins obtained by polymerizing petroleum fractions having 9 carbon atoms, and Examples thereof include hydrogenated resins, other petroleum resins, coumarone resins, indene resins and polyurethane resins.
Specifically, rosin, polymerized rosin, disproportionated rosin, hydrogenated rosin, maleated rosin, fumarized rosin and their glycerin ester, pentaerythritol ester, methyl ester, triethylene glycol ester, phenol modified product and ester thereof Rosins such as fluorides; terpene resins such as terpene polymers, terpene phenols, β-pinene polymers, aromatic modified terpene polymers, α-pinene polymers, terpene hydrogenated resins; petroleum fractions having 5 carbon atoms Petroleum resins obtained by polymerizing styrene, petroleum resins obtained by polymerizing petroleum fractions having 9 carbon atoms, and hydrogenated resins thereof; petroleum resins such as maleic acid modified products and fumaric acid modified products; polyisocyanate compounds and polyols described later Polyurethane obtained by reacting a compound and, if necessary, another compound For example, lettan resin.

Of these, terpene resins and polyurethane resins are preferable. Terpene resins are YS Resin PX / PXN, YS Polyster, Mighty Ace, YS Resin TO / TR, Clearon P / M / K (manufactured by Yashara Chemical Co., Ltd.), Tamanoru 803L / 901 (manufactured by Arakawa Chemical Co., Ltd.), Teltac 80 (Japan) Any of those commercially available as Terpen Chemical Co., Ltd.) can be used.

The polyurethane resin is preferably in the form of an aqueous emulsion in which polyurethane is dispersed in water.
Usually, the polyurethane resin can be obtained by reacting a polyisocyanate compound and a polyol compound, and if necessary, other compounds. Examples of the reaction include methods such as an acetone method, a prepolymer mixing method, a ketimine method, and a hot melt dispersion method.

Examples of the polyisocyanate compound include organic polyisocyanate compounds having two or more isocyanate groups in the molecule, which are used for ordinary polyurethane production. For example, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate (HDI), 2,2,4-trimethylhexamethylene diisocyanate, 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate, dicyclohexylmethane 4,4'-diisocyanate, methylcyclohexyl-2,4-diisocyanate, methylcyclohexyl-2,6-diisocyanate, xylylene diisocyanate (XDI), 1,3-bis (isocyanate) methylcyclohexane, tetramethylxylylene diisocyanate, trans Aliphatic diisocyanates such as cyclohexane-1,4-diisocyanate and lysine diisocyanate; 2,4-toluylene diisocyanate (TDI), 2,6-to Irene diisocyanate (TDI), diphenylmethane-4,4′-diisocyanate (MDI), 1,5′-naphthene diisocyanate, tolidine diisocyanate, diphenylmethylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, 4,4′-dibenzyl diisocyanate, 1, Aromatic diisocyanates such as 3-phenylene diisocyanate; lysine ester triisocyanate, triphenylmethane triisocyanate, 1,6,11-undecane triisocyanate, 1,8-isocyanate-4,4-isocyanate methyloctane, 1,3,3 Adducts of 6-hexamethylene triisocyanate, bicycloheptane triisocyanate, trimethylolpropane and toluylene diisocyanate And triisocyanates adducts such of trimethylol propane and 1,6-hexamethylene diisocyanate. You may use these individually or in combination of 2 or more types.

Examples of the polyol compound include compounds having two or more hydroxyl groups in the molecule, which are used for the production of ordinary polyurethane. For example, polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, trimethylolpropane, glycerin; polyethylene glycol, polypropylene glycol, polytetramethylene ether Polyether polyols such as glycol; adipic acid, sebacic acid, itaconic acid, maleic anhydride, terephthalic acid, isophthalic acid, fumaric acid, succinic acid, oxalic acid, malonic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid Dicarboxylic acids such as ethylene glycol, diethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, 1,2-propanedio 1,3-propanediol, 1,9-nonanediol, 3-methyl-1,5-pentanediol, 1,3-propanediol, tripropylene glycol, trimethylolpropane, glycerin and other polyol compounds. Polyester polyols such as polycaprolactone polyol and poly β-methyl-δ-valerolactone; polybutadiene polyols or hydrogenated products thereof, polycarbonate polyols, polythioether polyols, polyacrylate polyols, etc. .

The polyurethane resin preferably has a hydrophilic group in the molecule in order to improve dispersion stability in water. A polyurethane containing a hydrophilic group in the molecule is called an ionomer structure and has a surface-active ability in itself. Therefore, there exists a tendency which is easy to disperse | distribute in water, and there exists a tendency which improves the water resistance of the aqueous emulsion obtained by emulsion-polymerizing a monomer further to the polyurethane aqueous emulsion.

As the hydrophilic group, anionic groups such as a sulfonyl group and a carboxyl group are preferable, and a sulfonyl group is more preferable. This is because there is a tendency to further improve the water resistance of an aqueous emulsion obtained by emulsion polymerization of monomers.
In general, the anionic group is preferably neutralized by a neutralizing agent.
Examples of the neutralizing agent include tertiary amine compounds such as triethylamine and trietalamine; inorganic alkali compounds such as sodium hydroxide; ammonia and the like.

In order to introduce a hydrophilic group into the molecule, it is preferable to use the following compounds during the production of polyurethane. Examples of the compound include a nonionic hydrophilic group such as a structural unit derived from polyethylene glycol in the molecule, and a sulfonyl group, carboxyl group, hydroxyl group, primary amino group (—NH ₂ ), secondary amino group ( ═NH) and the like (hereinafter also referred to as “hydrophilic group-containing compound”) having at least one active hydrogen having reactivity with an isocyanate group.

Examples of the hydrophilic group-containing compound include 3,4-diaminobutanesulfonic acid, 3,6-diamino-2-toluenesulfonic acid, 2,6-diaminobenzenesulfonic acid, and N- (2-aminoethyl) -2. A sulfonic acid-containing compound such as aminoethylsulfonic acid; a carboxylic acid-containing compound such as 2,2-dimethylollactic acid, 2,2-dimethylolpropionic acid, and 2,2-dimethylolvaleric acid. You may use these individually or in combination of 2 or more types.

When the polyurethane resin is produced as an aqueous emulsion, it is a compound different from the hydrophilic group-containing compound for the purpose of chain extension, molecular weight adjustment, etc., if necessary, and contains active hydrogen capable of reacting with an isocyanate compound in the molecule. A compound to be used may be used in combination. Examples of such compounds include polyvalent amine compounds such as ethylenediamine, 1,4-butanediamine, and 1,6-hexanediamine; tertiary amine-containing polyhydric alcohols such as triethanolamine, methanol, ethanol, and butanol. And monoalcohols.

As the polyurethane resin, a commercially available polyurethane aqueous emulsion or a commercially available water-soluble urethane resin may be used as it is.
For example, a polyurethane dispersion (or polyurethane liquid) in which a polyurethane resin is dispersed or dissolved in water can be used. In the polyurethane dispersion, the amount of the polyurethane resin is usually 10 to 70% by weight, preferably 30 to 50% by weight.
The polyurethane dispersion may further contain an organic solvent containing no isocyanate reactive group, for example, ethyl acetate, acetone, methyl ethyl ketone, N-methylpyrrolidone and the like. The amount of the organic solvent can usually be 0.1 to 100 parts by weight with respect to 100 parts by weight of water in the polyurethane dispersion.

As the water-soluble urethane resin, for example, manufactured by Sumitomo Bayer Urethane Co., Ltd .; Dispacol U-42, U-53, U-54, U-56, KA-8484, KA-8484, KA-8755, KA-8756 KA-8766, manufactured by DIC Corporation; Hydran HW-111, HW-311, HW-333, HW-350, HW-337, HW-374, AP-20, AP-60LM, AP-80, Sanyo Chemical Manufactured by Kogyo Co., Ltd .; Uprene UXA-306, UXA-307, Permarin UA-150, Permarin UA-200, Permarin UA-300, Permarin UA-310, Eucort UWS-145, Daiichi Kogyo Seiyaku Co., Ltd .; Super Flex 107M, 110, 126, 130, 150, 160, 300, 361, 370, 410, 420, 60, 700, 750, 820, manufactured by ADEKA; Adekabon titer HUX-401, HUX-420A, HUX-380, HUX-561, HUX-210, HUX-822, HUX-895, HUX-830, etc. .

When the water-based adhesive of the present invention contains other resin, preferably the ethylene- (meth) acrylate-maleic anhydride copolymer: other resin (nonvolatile content ratio) is 50:50 to 90:10 More preferably, it is 50:50 to 80:20. The form of these resins may be an emulsion, or may be emulsified together with an ethylene- (meth) acrylate-maleic anhydride copolymer.

When the aqueous adhesive of the present invention contains other resins, the content can be appropriately adjusted depending on, for example, the type of resin used, the purpose of use, the performance to be obtained, and the like. For example, from the viewpoint of maintaining the stability of the water-based adhesive, keeping the viscosity moderate, and exhibiting good coating film forming ability, it is preferably 1 to 60% by weight with respect to the total amount of the water-based adhesive. The amount is preferably 3 to 60% by weight, 3 to 50% by weight, and more preferably 5 to 55% by weight. Further, for example, from the viewpoint of exerting a function as a pressure-sensitive adhesive resin or a tackifier, it is preferably 1 to 99% by weight, more preferably 3 to 99% by weight, based on the total amount of the aqueous adhesive. Preferably, it is 5 to 90% by weight.

<Surfactant>
The aqueous adhesive of the present invention preferably further contains a surfactant that generally acts as an emulsifier. Such a surfactant may be any of cationic, anionic, amphoteric and nonionic surfactants, and among them, an anionic or nonionic surfactant is preferable. Particularly preferred are those having the structure of formula (I). The surfactants may be used alone or in combination of two or more, but it is preferable to use at least two types in combination. Among these, it is more preferable to use at least two kinds of surfactants having the structure of the formula (I).
X in the formula (I) is a hydrogen atom, —SO ₃ M (M is a hydrogen atom, —NH ₄ or an alkali metal), that is, sulfuric acid, sulfate (for example, an alkali metal salt such as ammonium salt or sodium), etc. Among them, a hydrogen atom, —SO ₃ H or —SO ₃ NH ₄ is preferable.
As combinations of at least two kinds of surfactants, those having the same X and different n and / or m may be combined, but those having the same or different n and / or m and different X may be combined. preferable. Specifically, X is a combination of a hydrogen atom and —SO ₃ H, a combination of a hydrogen atom and —SO ₃ NH ₄ , or a combination of —SO ₃ H and —SO ₃ NH ₄ . Of these, a combination of a hydrogen atom and —SO ₃ NH ₄ is preferable.

As the surfactant represented by the formula (I), Latemul AD-25 (manufactured by Kao Corporation), Latemuru E-1000A (manufactured by Kao Corporation) represented by the following formula (A), the following formula (B) And Neugen EA-177 (Daiichi Kogyo Seiyaku Co., Ltd.) represented by

(In the formula, m represents an integer of 1 to 100.)

The aqueous adhesive of the present invention may contain a surfactant other than the surfactant represented by the formula (I).
For example, the anionic surfactants include higher alcohol sulfates, higher alkyl sulfonates, higher carboxylates, alkyl benzene sulfonates, polyoxyethylene alkyl sulfate salts, polyoxyethylene alkyl phenyl ether sulfate salts, vinyls. Examples include sulfosuccinate.
Examples of cationic surfactants include alkylammonium salts such as dodecyltrimethylammonium salt and cetyltrimethylammonium salt, alkylpyridium salts such as cetylpyridium salt and decylpyridium salt, oxyalkylenetrialkylammonium salt, dioxyalkylenedialkylammonium salt , Allyl trialkyl ammonium salt, diallyl dialkyl ammonium salt and the like.
Nonionic surfactants include polyoxyethylene alkyl ethers such as polyoxyethylene propylene ether, polyoxyethylene alkyl phenyl ether, polyethylene glycol fatty acid esters, ethylene oxide propylene oxide block copolymers, polyoxyethylene fatty acid amides, and ethylene oxide. -A compound having a polyoxyethylene structure such as a propylene oxide copolymer or a sorbitan derivative such as a polyoxyethylene sorbitan fatty acid ester.
Examples of amphoteric surfactants include lauryl betaine and lauryl dimethylamine oxide.

The content of the surfactant is usually 0.1 to 50 parts by weight, preferably 0.1 to 20 parts by weight based on 100 parts by weight of the above-mentioned ethylene- (meth) acrylate-maleic anhydride copolymer. Part, more preferably 0.1 to 10 parts by weight.
When the aqueous adhesive of the present invention contains a surfactant other than the surfactant represented by the formula (I), the surfactant represented by the formula (I) is represented by the formula (I). The total content of the surfactants other than the surfactant is usually 0.1 to 50 parts by weight, preferably 100 parts by weight of the ethylene- (meth) acrylate-maleic anhydride copolymer, preferably The amount is 0.1 to 20 parts by weight, and more preferably 0.1 to 10 parts by weight.
When the aqueous adhesive of the present invention contains a resin other than the ethylene- (meth) acrylate-maleic anhydride copolymer, the content of the surfactant is usually 100 wt% of the resin contained in the aqueous adhesive. 0.1 to 50 parts by weight, preferably 0.1 to 20 parts by weight, and more preferably 0.1 to 10 parts by weight with respect to parts.
When the surfactant represented by the formula (A) and the surfactant represented by the formula (B) are used in combination, the weight ratio is preferably 1 to 99:99 to 1, more preferably 5 to 95: 95-5, more preferably 10-90: 90-10, particularly preferably 30: 70-90: 10, 40: 60-90: 10, 50: 50-90: 10.

<Basic compound>
The aqueous adhesive of the present invention preferably further contains a basic compound.
As a basic compound, what can neutralize a carboxyl group is preferable, for example, ammonia, an organic amine compound, a metal hydroxide, etc. are mentioned. Preferably, it is ammonia or an organic amine compound. In particular, an organic amine compound having a boiling point of 200 ° C. or less can be easily dispersed by ordinary drying, and when forming a coating film using an aqueous adhesive, the water resistance and alkali resistance of the coating film are maintained or It can be improved and is preferable.
Examples of the organic amine compound include triethylamine, N, N-dimethylethanolamine, aminoethanolamine, N-methyl-N, N-diethanolamine, isopropylamine, iminobispropylamine, ethylamine, diethylamine, 3-ethoxypropylamine, Examples include 3-diethylaminopropylamine, sec-butylamine, propylamine, methylaminopropylamine, 3-methoxypropylamine, monoethanolamine, morpholine, N-methylmorpholine, N-ethylmorpholine and the like. Of these, N, N-dimethylethanolamine and the like are preferable.
Examples of the metal hydroxide include lithium hydroxide, potassium hydroxide, sodium hydroxide and the like.

When the aqueous adhesive of the present invention contains a basic compound, the content thereof is preferably 1 to 30% by weight, more preferably 2 to 20% by weight, based on the copolymer. More preferably, it is 2 to 10% by weight.

<solvent>
The aqueous adhesive of the present invention preferably contains no solvent. However, in some cases, in addition to water, for example, aromatic hydrocarbons such as toluene and xylene; aliphatic hydrocarbons such as hexane; ethyl acetate, Esters such as butyl acetate; ketones such as methyl ethyl ketone and methyl isobutyl ketone; alcohols such as methanol, ethanol, n-propanol, isopropyl alcohol, and n-butanol; glycols such as ethylene glycol, diethylene glycol, triethylene glycol, and propylene glycol Solvents, methyl cellosolve, cellosolve, butyl cellosolve, dioxane, MTBE (methyl tertiary butyl ether), cellsolve solvents such as butyl carbitol, diethylene glycol monomethyl ether, triethylene glycol Glycol solvents such as nomethyl ether, propylene glycol monomethyl ether, 3-methoxy-3-methyl-1-butanol, ethylene glycol monomethyl ether acetate, PMA (propylene glycol monomethyl ether acetate), diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether An organic solvent such as a glycol ester solvent such as acetate; You may use these individually or in combination of 2 or more types.
When the aqueous adhesive of the present invention contains a solvent, its content is usually 0.01 to 30 parts by weight, preferably 100 to 30 parts by weight, preferably 100 parts by weight of ethylene- (meth) acrylate-maleic anhydride copolymer. 0.01 to 10 parts by weight.

<Other ingredients>
The aqueous adhesive of the present invention usually contains water. Furthermore, phenol stabilizers, phosphite stabilizers, amine stabilizers, amide stabilizers, anti-aging agents, weathering stabilizers, anti-settling agents, as required, without compromising the intended properties of the water-based adhesive. Stabilizers, antioxidants, heat stabilizers, light stabilizers, etc .; thixotropic agents, thickeners, dispersants, antifoaming agents, viscosity modifiers, weathering agents, pigments, pigment dispersants, antistatic agents, Additives such as lubricants, nucleating agents, flame retardants, oils, dyes, curing agents (crosslinking agents); transition metal compounds such as titanium oxide (rutile type) and zinc oxide; pigments such as carbon black; glass fibers, carbon fibers, Potassium titanate fiber, wollastonite, calcium carbonate, calcium sulfate, talc, glass flake, barium sulfate, clay, kaolin, fine powder silica, mica, calcium silicate, aluminum hydroxide, magnesium hydroxide Beam, aluminum oxide, magnesium oxide, alumina, inorganic, such as celite, may contain organic fillers, and the like.

(water)
As the water contained in the aqueous adhesive of the present invention, tap water, deionized water or the like is generally used. In order to further improve the stability of the aqueous adhesive, a water-soluble resin such as polyvinyl alcohol, sodium polyacrylate, carboxymethyl cellulose, or hydroxyethyl cellulose may be added.
The water content is, for example, 20% by weight or more, preferably 30% by weight or more, more preferably 40% by weight or more, still more preferably 50% by weight or more based on the total amount of the aqueous adhesive. % By weight or less, preferably 85% by weight or less, more preferably 80% by weight or less, and further preferably 70% by weight or less.

(Thickener)
Thickeners can be used to adjust the viscosity of the formulation. As a thickener, manufactured by ADEKA Corporation; Adecanol UH-140S, UH-420, UH-438, UH-450VF, UH-462, UH-472, UH-526, UH-530, UH-540, UH -541VF, UH-550, UH-752, H-756VF, manufactured by San Nopco; SN thickener 920, 922, 924, 926, 929-S, A-801, A-806, A-812, A-813, A -818, 621N, 636, 601, 603, 612, 613, 615, 618, 621N, 630, 634, 636, 4050 and the like.

(Dispersant)
The dispersant can be used for improving the wettability of the coated substrate. As a dispersant, manufactured by ADEKA Corporation; Adeka Coal W-193, W-287, W-288, W-304, manufactured by BYK; BYK-333, BYK-345, BYK-346, BYK-347, BYK -348, BYK-349, BYK-378, manufactured by San Nopco; Nopco wet 50, SN wet 366, Nopco 38-C, SN disperse sand 5468, 5034, 5027, 5040, 5020 and the like.

(Curing agent)
Examples of the curing agent include diphenylmethane diisocyanate (MDI), tolylene diisocyanate (TDI), hexamethylene diisocyanate (HDI), xylene diisocyanate (XDI), and oligomers or polymers thereof, which are isocyanate curing agents. Specific examples include Sumidur 44V20, Sumidur N3200, N3300, N3400, N3600, N3900, S-304, S-305, XP-2655, XP-2487, XP-2547 and the like made by Sumika Bayer Urethane. . The curing agent is preferably 0.1 to 20 parts by weight, more preferably 0.1 to 10 parts by weight with respect to 100 parts by weight of the aqueous adhesive. The curing agent may be added after being dissolved in an organic solvent.

<Method for producing water-based adhesive>
The method for producing the aqueous adhesive of the present invention is a method known in the art, for example, a post-emulsification method (for example, a forced emulsification method, a method of dispersing the copolymer in an aqueous medium after obtaining the copolymer by polymerization) Any of the self-emulsification method and the phase inversion emulsification method) can be used.
Specifically, (1) A copolymer and a solvent are charged into a reactor, stirred and heated to dissolve, and a surfactant, water and / or solvent are charged into the reactor, and heated and stirred. (2) A copolymer and optionally a solvent are added to a kneader, and the mixture is stirred and heated and melted, and then a surfactant, water and / or Examples thereof include a method of adding a solvent, heating and stirring, and optionally adding water and / or a solvent before and after this and stirring.

In the production method of (1) described above, as the reactor, a container (preferably a sealed container, pressure-resistant container) provided with a heating device that can be heated and a stirrer that can apply a shearing force or the like to the contents. Container).
A normal stirrer can be used. Examples of such a pressure vessel include a pressure-resistant autoclave with a stirrer. Stirring may be performed, for example, at normal pressure or reduced pressure. The rotation speed of the stirrer is usually 50 to 1000 r. p. m. It can be performed at the number of rotations. If necessary, it is preferable to increase the rotational speed as the dispersion of the water-based adhesive proceeds.
The heating is usually performed at 50 to 200 ° C, preferably 60 to 150 ° C, more preferably 70 to 100 ° C.
After stirring, the solvent is preferably distilled off from the obtained dispersion (preferably, vacuum distillation or pressure distillation). As a method for distilling off, a method known in the art can be used. When performing vacuum distillation or pressure distillation, the degree of pressure reduction or pressure is usually ± 0.001 to 1 MPa, preferably ± 0.001 to 0.5 MPa.

In the production method (2) described above, examples of the kneader include a roll mill, a kneader, an extruder, an ink roll, and a Banbury mixer. In particular, an extruder or a multi-screw extruder having one or more screws in the casing may be used.

As a method of stirring using an extruder, a molten ethylene- (meth) acrylate-maleic anhydride copolymer and a surfactant are mixed, and this is continuously fed from the hopper or feed port of the extruder, This is melted and kneaded by heating, and water is supplied from at least one supply port provided in the compression zone, metering zone, degassing zone, etc. of the extruder, kneaded with a screw, and then continuously extruded from a die. .

In addition, it is preferable to add suitably other components mentioned above, such as a component other than the above, an antifoamer, a viscosity modifier, in the manufacture process of an aqueous adhesive.
Further, in the production process of the water-based adhesive, the surfactant is preferably used within a desired range. However, when the surfactant is used in excess, it is optionally excessive from the obtained water-based adhesive. The surfactant may be separated and removed. Separation and removal of the surfactant may be performed, for example, by using a centrifuge, a filter having an average pore size smaller than the average particle size of the aqueous adhesive (preferably having an average pore size of 0.05 to 0.5 μm). And a method using an ultrafiltration membrane).
Furthermore, it is preferable to cool the obtained water-based adhesive. Thereby, the water-based adhesive containing the fine particle of resin is obtained. The cooling is not particularly required to be performed at a low temperature, and a method of leaving it at room temperature can be mentioned. Thereby, a fine and homogeneous aqueous adhesive can be obtained without aggregation of resin or the like during the cooling process.

The particle size of the dispersoid contained in the aqueous adhesive of the present invention is usually 10 μm or less, preferably 0.01 to 10 μm, more preferably 0.01 to 2 μm, and still more preferably 0.01 to 10 μm. It is 1 μm and the stationary stability is good.
Here, the number-based particle size is a particle size corresponding to 50% of the cumulative particle size distribution value on the number basis, and the volume-based median size is 50% of the cumulative particle size distribution value on the volume basis. Corresponding particle size. The particle diameter means a median diameter value measured on a number basis unless otherwise specified.
Moreover, you may filter using the filter etc. which have various hole diameters as needed, for example.

<Usage method of water-based adhesive>
The aqueous adhesive of the present invention exhibits functions such as an adhesive, an adhesive, an adhesive modifier, a heat sealant, a paint, a primer for paint, an ink binder, an adhesive and an emulsion modifier, It can be used for bonding various materials (adherents) used in films, sheets, structural materials, building materials, automobile parts, electrical / electronic products, packaging materials, clothing, shoes, and the like.

The material of the adherend includes wood-based materials such as wood, plywood, medium density fiberboard (MDF), particle board, fiber board; cellulosic materials such as cotton cloth, cotton-containing fiber, linen cloth, rayon; polyethylene (ethylene Polyolefins such as a polyolefin having a structural unit derived from the main component), polypropylene (polyolefin having a structural unit derived from propylene as a main component), polystyrene (polyolefin having a structural unit derived from styrene as a main component), polycarbonate, Acrylonitrile / butadiene / styrene copolymer (ABS resin), (meth) acrylic resin polyester, polyether, polyvinyl chloride, polyurethane, foamed urethane, ethylene / vinyl acetate copolymer (EVA), foamed EVA, nylon 6, nylon 66 grade polyamide Resin or plastic material of the foam, and the like; polyurethanes, polyamide and synthetic leather polyamino acid; glass, ceramic material, ceramic or the like; iron, stainless steel, copper, a metal material such as aluminum and the like. These may be composite materials composed of a plurality of materials. Further, an inorganic filler such as talc, silica and activated carbon, a kneaded molded product of carbon fiber or the like and a plastic material may be used.
Especially, it is suitable for adhesion between ethylene / vinyl acetate copolymer, cotton-containing fiber, nylon resin, polyolefin, synthetic leather and the like.

Here, polyurethane is a polymer crosslinked by a urethane bond, and is usually obtained by reaction of alcohol (—OH) and isocyanate (—NCO). The urethane foam is a polyurethane foamed with a volatile solvent such as carbon dioxide or freon produced by a reaction between isocyanate and water used as a crosslinking agent. Semi-rigid polyurethane is used for automobile interiors, and hard polyurethane is used for paints.

An ethylene / vinyl acetate copolymer is generally a radical copolymer of ethylene and vinyl acetate at a high temperature and a high pressure, and the properties differ depending on the content of vinyl acetate and the like. The ethylene / vinyl acetate copolymer includes those having various vinyl acetate contents and forms (film, block, fiber, foam) which are widely used and used in various applications. In the ethylene-vinyl acetate copolymer, polyolefin or the like may be used in combination. Preferred polyolefins include ethylene-octene copolymer, ethylene-butene copolymer, polypropylene and polyethylene.

The cotton-containing fibers may be 100% cotton fibers, or may be blended fibers of cotton and other natural fibers and / or chemical fibers. Other natural fibers include wool, silk, hemp and the like. Chemical fibers include synthetic fibers (for example, polyamide fibers such as polyester and nylon), semi-synthetic fibers (cellulose fibers such as acetate, protein fibers such as promix), and regenerated fibers (rayon, cupra, polynosic, etc.) Cellulosic fibers), inorganic fibers (carbon fibers, glass fibers) and the like.
Examples of the form of the cotton-containing fiber that is the adherend of the aqueous adhesive of the present invention include various forms such as a woven fabric, a knitted fabric, a nonwoven fabric, a knitted fabric, a felt, a film, and a block shape.

Nylon resin is a so-called polyamide-based resin, and various types such as the type and molecular weight of the constituent monomer are included as long as the monomer is a polymer condensed by an amide bond. Specifically, nylon 6, nylon 6,6, nylon 4,6, nylon 11, nylon 12, etc. are mentioned. The nylon resin may have any form such as a film, block, fiber, or foam.

The polyolefin is a thermoplastic resin obtained by polymerizing an olefin, and examples thereof include homopolymers and copolymers having structural units derived from α-olefins having 2 to 20 carbon atoms.
Examples of the α-olefin having 2 to 20 carbon atoms include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, -Dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicocene, vinylcyclohexane and the like. Preferred are ethylene, propylene and the like. Examples of the copolymer having a structural unit derived from an α-olefin having 2 to 20 carbon atoms include those described later.
In particular, polyethylene has various properties such as high-density polyethylene, low-density polyethylene, ultra-low-density polyethylene, linear low-density polyethylene, and ultra-high-molecular-weight polyethylene depending on the difference in molecular weight. The polyethylene as the adherend includes any of these.
Polypropylene is a thermoplastic resin obtained by polymerizing propylene, and there are polypropylenes having different isotactic (isotactic), syndiotactic, and atactic stereoregularity due to the difference in stereoregularity. Polypropylene as an attachment includes any of these.

Synthetic leather includes both synthetic leather and artificial leather in the narrow sense. In other words, synthetic leather coated with synthetic resin on natural or synthetic fabric, etc., or synthetic fiber impregnated with fabric (usually non-woven fabric) such as microfiber is used as it is or coated with synthetic resin as a base material. Any of the above-mentioned artificial leathers may be used, and the synthetic resin used in these includes any of polyurethane, polyamide and polyamino acids. Among them, the synthetic resin is preferably a polyurethane system. As for the shape of the synthetic leather, various types such as a film, a sheet, and a block shape can be mentioned. Usually, a film and a sheet shape are used.

The water-based adhesive of the present invention is a constituent material such as a cover, a midsole, and an outer bottom of footwear including men's shoes and women's shoes such as sports shoes, town shoes, and business shoes, and industrial work shoes. It is suitably used as an adhesive for bonding the adherends.

In addition, the surface of these adherends may be smooth or may have irregularities. Moreover, you may give the primer process for improving adhesion | attachment with an adhesive agent etc. to those surfaces. Examples of the primer treatment include blast treatment, chemical treatment, degreasing, flame treatment, oxidation treatment, steam treatment, corona discharge treatment, ultraviolet irradiation treatment, plasma treatment, and ion treatment anchor layer formation.

In order to adhere the first base material and the second base material, the aqueous adhesive of the present invention is first applied to either one, preferably both, to form a coating film.
As a method for forming a coating film, the water-based adhesive of the present invention was applied to one or both surfaces of a known film-forming method, ethylene / vinyl acetate copolymer and cotton-containing fiber, and left at room temperature as necessary. After that, there is a method of subjecting to a heat treatment for drying or drying and baking. Depending on the composition of the water-based adhesive, it may be formed into a film by extrusion, or may be applied to various substrate surfaces and dried to form the resulting film. It may be sandwiched between the coalesced and the cotton-containing fiber and bonded under pressure (or heating).
Examples of the application method include gravure roll coating, reverse roll coating, bar coating, wire bar coating, lip coating, air knife coating, curtain flow coating, spray coating, dip coating, brush coating, spatula coating, and the like.

In addition, before apply | coating a water-based adhesive, you may give a primer process to the surface of a 1st base material and / or a 2nd base material as mentioned above. Examples of the primer treatment include blast treatment, chemical treatment, degreasing, flame treatment, oxidation treatment, steam treatment, corona discharge treatment, ultraviolet irradiation treatment, plasma treatment, ion treatment, anchor layer formation, and the like.
In particular, when using a substrate that can absorb water, such as cotton-containing fibers, a water-based adhesive may be applied and dried as a primer treatment. Application | coating of the water-based adhesive here can utilize the said method, and drying can be performed by the method mentioned later. The water-based adhesive used for the primer treatment may be only one type, may be a laminate of two or more types, may be the same in the first and second substrates, or different. There may be.

Drying or heat treatment may be natural drying, non-thermal drying such as air drying, or normal hot air circulation type oven, infrared or far infrared heater, electromagnetic wave (for example, electromagnetic wave having a frequency band of 2.45 ± 0.02 GHz). It can be carried out by heat drying using a microwave oven or the like. The heating temperature and the heating time can be appropriately adjusted according to the characteristics of the substrate, the composition of the aqueous adhesive of the present invention, and the like. The heating temperature is usually 30 to 150 ° C, preferably 40 to 85 ° C. The heating time is usually 1 second to 1 hour, preferably 5 seconds to 30 minutes, and more preferably 5 seconds to 10 minutes.
The application and drying or heat treatment of the water-based adhesive may be performed only once, or may be performed twice or more. At that time, the coating method and the drying method may be combined with each other, or may be combined with different methods. Moreover, you may combine the frequency band from which electromagnetic waves differ.

When laminating the first and second substrates, heat, pressure or both may be applied. In the case of applying heat, it is necessary to set the temperature range in which the first base material, the second base material, and the adhesive layer do not deteriorate, and the temperature is preferably 120 ° C. or lower, more preferably 100 ° C. or lower. The heat load may be performed using the above-described normal hot air circulation type oven, infrared heater, microwave oven, or the like. The pressure when the pressure is applied is usually 100 g / cm ² or more, which is less than the pressure at which the shapes of the first base material and the second base material are deformed.
In addition, after the first and second base materials are bonded, the obtained laminated structure may be subjected to the above-described drying or heat treatment (for example, electromagnetic wave irradiation), and further, a pressure load may be applied. Good.

The thickness of the coating film formed using the aqueous adhesive of the present invention can be appropriately adjusted depending on the form of the first base material and the second base material that are adherends, The thickness is 0.01 to 300 μm, preferably 0.01 to 200 μm.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. Parts and% in the examples mean weight basis unless otherwise specified.
The solid content was measured by a measuring method according to JIS K-6828.
The particle size of the dispersoid contained in the aqueous emulsion is a value measured with a laser diffraction particle size measuring device LA-950V2 manufactured by HORIBA. Unless otherwise specified, it is a median diameter value measured on a number basis.

<Production Example 1 of Aqueous Emulsion>
As shown in Table 1, in a 2 liter separable flask reaction vessel equipped with a stirrer, a thermometer and a reflux condenser, 200 parts of toluene as a solvent and a polymer as a copolymer (U1; BONDINE HX8290, manufactured by ARKEMA) ) 100 parts were added and stirred and dissolved at 80 ° C. Next, as a surfactant, a mixed solution of Latemul E-1000A (30% aqueous solution, manufactured by Kao Corporation) 0.34 parts, Neugen EA-177 (Daiichi Kogyo Seiyaku Co., Ltd.) 0.1 parts, and isopropanol 5 parts Was added dropwise over 10 minutes. After further stirring for 5 minutes, 5 parts of dimethylethanolamine was added, and the mixture was further stirred for 5 minutes.
Subsequently, the stirring apparatus was changed to TK Robotics (manufactured by PRIMIX Co., Ltd.), and a mixture of 100 parts of isopropanol and 100 parts of ion-exchanged water was added dropwise over 30 minutes while stirring the reaction mixture with a disper blade. When fluidity was recognized in the reaction mixture, the stirring blade was changed to a homomixer, and 300 parts of ion-exchanged water was added dropwise while stirring to obtain a milky white dispersion.
The obtained dispersion was put into a 2 L eggplant flask, distilled under reduced pressure with an evaporator, and filtered with a 200 mesh nylon net to obtain an aqueous emulsion containing a polymer (U1) and a surfactant. The particle size (number basis) of the dispersoid contained in the aqueous emulsion (E-1) obtained was 0.2 μm, and the non-volatile content was 39%.

<Production Examples 2 and 3 of aqueous emulsion>
Using the copolymers and surfactants shown in Table 1 in the weight ratios shown in Table 1, emulsions (E-2) and (E-3) were produced in substantially the same manner as in <Preparation Example 1 of Aqueous Emulsion>. Obtained.
The copolymers and surfactants in Table 1 are as follows.
Copolymer U1: BONDINE HX8290, manufactured by ARKEMA Copolymer U2: BONDINE LX4110, manufactured by ARKEMA Copolymer U3: BONDINE HX8210, manufactured by ARKEMA Surfactant 1: Latem E-1000A, 30% aqueous solution, Kao Corporation Surfactant 2: Neugen EA-177, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.

<Examples 1 to 7: Production of water-based adhesive, evaluation of M-EVA adhesion and heat resistance>
As shown in Table 2-1, terpene phenol as the adhesive resin 1 was added to the aqueous emulsions (E-1) to (E-3) (non-volatile content ratio, unit: parts by weight) obtained in the production examples of the aqueous emulsion. An aqueous emulsion (Tamanol E-200NT, manufactured by Arakawa Chemical Co., Ltd.) and an aqueous urethane emulsion (Disco Pearl U-54, manufactured by SBU) as the adhesive resin 2 were blended so that the solid content ratio was 100: 100: 100. Furthermore, Adecanol UH-756VF (manufactured by ADEKA) was added as a thickener, Nopco Wet 50 (manufactured by San Nopco) was added as a dispersant, and Desmodur N3300 (manufactured by SBU) was added as a crosslinking agent. After preparing with water so that the non-volatile content was 40%, the mixture was stirred with a three-one motor to obtain aqueous adhesives F2 to F8 and F10.

The obtained water-based adhesive F10 of Table 2-1 was applied to 100% cotton canvas using a glass rod (coating amount: weight after drying: about 130 g / m ² ), air dried for 20 minutes, and 3000 W Electromagnetic wave treatment was performed for 30 seconds.
In addition, each of the water-based adhesives F2 to F8 was given a bar coater No. 75 is applied to M-EVA (ethylene / vinyl acetate copolymer foam) (coating amount: about 30 g / m ² after drying), and the obtained M-EVA is irradiated with an electron wave at 3000 W for 110 seconds. Processed. Thereafter, an aqueous adhesive (F10) was applied to cotton canvas and M-EVA using a glass rod (cotton canvas coating amount: weight after drying: about 70 g / m ² , M-EVA coating amount: weight after drying: about 70 g / m m ² ), and M-EVA was subjected to electromagnetic wave treatment at 3000 W for 15 seconds.
Subsequently, the coated surfaces of the cotton canvas and the M-EVA aqueous adhesive were bonded together and subjected to electromagnetic wave treatment at 3900 W for 120 seconds. Then, it crimped | bonded by hand. Thus, a laminated structure composed of cotton / adhesive layer / M-EVA was obtained.

Each of the obtained laminated structures was allowed to stand at room temperature for 24 hours, and then, using a tensile tester (manufactured by Shimadzu Corporation, Autograph), at a peeling rate of 50 mm / min and a peeling angle of 180 degrees, the adhesion of the laminated structure. Was evaluated by measuring the peel strength. The results are shown in Table 2-2.
○: Peel strength of 70 N / inch or more.
X: Peel strength is less than 70 N / inch.

Each of the obtained laminated structures was allowed to stand at room temperature for 24 hours, and then, using a tensile tester (manufactured by Toyo Seiki, Strograph T), a set temperature in the tank of 60 ° C., a peeling speed of 50 mm / min, and a peeling angle of 180 degrees Thus, the heat resistance of the laminated structure was evaluated by measuring the peel strength. The results are shown in Table 2-2.
○: Peel strength of 15 N / inch or more.
X: Peel strength is less than 15 N / inch.

<Production Examples 4 to 7 of aqueous emulsion>
Using the copolymers and surfactants shown in Table 3 in the weight ratios shown in Table 3, aqueous emulsions (E-4) to (E-7) were produced in substantially the same manner as in <Preparation Example 1 of aqueous emulsion>. )
The copolymers and surfactants in Table 3 are as follows.
Copolymer P1: C ₂ / EVA / MAH copolymer (OREVAC T9314, manufactured by ARKEMA)
Copolymer P2: C ₂ / EVA / MAH copolymer (OREVAC T9318, manufactured by ARKEMA)
Copolymer U1: BONDINE HX8290, manufactured by ARKEMA Copolymer U2: BONDINE LX4110, manufactured by ARKEMA Surfactant 1: Latemul E-1000A, 30% aqueous solution, manufactured by Kao Corporation Surfactant 2: Neugen EA-177, Made by Daiichi Kogyo Seiyaku Co., Ltd.

<Examples 8 to 11: Production of aqueous adhesive and evaluation of adhesion to M-EVA>
To 100 parts by weight of each aqueous emulsion (non-volatile content ratio) obtained in the production example of an aqueous emulsion, Adecanol UH-420 (manufactured by ADEKA) as a thickener, and Nopco Wet 50 (manufactured by San Nopco) as a dispersant, Add the amount shown in Table 4 (nonvolatile content ratio, unit: parts by weight) and adjust with water so that the non-volatile content of the formulation is 40%, and stir with a three-one motor to produce aqueous adhesive D did.

The obtained water-based adhesive D in Table 4 was applied to 100% cotton canvas using a glass rod (coating amount: weight after drying: about 130 g / m ² ), and air-dried for 1 hour.
Also, the same water-based adhesive D applied to cotton was applied to the bar coater No. 75 was applied to M-EVA (foamed ethylene / vinyl acetate copolymer) (weight application amount after drying: about 30 g / m ² ), and the obtained M-EVA was naturally dried for 1 hour. Then, apply it to cotton canvas and M-EVA using a glass rod (cotton canvas: weight after drying about 70 g / m ² , M-EVA application amount: weight after drying about 30 g / m ² ), put in a microwave oven, Electromagnetic wave treatment was performed at 750 W for 30 seconds.
Subsequently, the coated surfaces of cotton canvas and M-EVA water-based adhesive were bonded together and pressure-bonded.
The cotton / adhesive layer / M-EVA laminated structure thus obtained was again placed in a microwave oven and subjected to electromagnetic wave treatment at 750 W for 110 seconds. After removing from the dryer, it was crimped by hand. Thus, a laminated structure composed of cotton / adhesive layer / M-EVA was obtained.
The obtained laminated structure was allowed to stand at room temperature for 24 hours, and the adhesion of the laminated structure was evaluated by the same method and evaluation criteria as described above. The results are shown in Table 4.

<Standing stability for 5 days>
The following tests were conducted on the aqueous emulsions obtained in the above production examples of aqueous emulsions.
The obtained aqueous emulsion was put into a 250 mL plastic container and allowed to stand at room temperature for 5 days, and then the appearance change was observed. As a result, all of the water-based emulsions (E-1) to (E-7) are homogeneously dispersed by visual observation, and aggregation, precipitation, phase separation, etc. occur even after long-term storage. It showed good stability.

According to the aqueous adhesive of the present invention, the adherend can be firmly bonded.

Claims (18)

1. An aqueous adhesive comprising at least two ethylene- (meth) acrylate-maleic anhydride copolymers having different compositions.
2. Furthermore, the water-based adhesive of Claim 1 containing surfactant represented by following formula (I).
   

   

   (In the formula, X represents a hydrogen atom or —SO ₃ M (M is a hydrogen atom, NH ₄ or an alkali metal). N represents an integer of 1 to 3. m represents an integer of 1 to 100.)
3. The aqueous adhesive according to claim 2, wherein the surfactant includes at least two of a surfactant in which X is a hydrogen atom and a surfactant in which X is -SO ₃ M.
4. 4. The aqueous adhesive according to claim 2, wherein —SO ₃ M in the surfactant is —SO ₃ NH ₄ .
5. The surfactant is a surfactant represented by the formula (A) and a surfactant represented by the formula (B) in a weight ratio of 1 to 99:99 to 1, 5 to 95:95 to The water-based adhesive according to any one of claims 2 to 4, comprising 5, 10 to 90:90 to 10, 30:70 to 90:10, 40:60 to 90:10, or 50:50 to 90:10. Agent.
   

   

   (In the formula, m represents an integer of 1 to 100.)
6. 6. The surfactant according to claim 2, wherein the surfactant contains 0.1 to 50 parts by weight, 0.1 to 20 parts by weight, or 0.1 to 10 parts by weight with respect to 100 parts by weight of the resin contained in the aqueous adhesive. The water-based adhesive according to any one of the above.
7. The ethylene- (meth) acrylate-maleic anhydride copolymer has a structural unit molar ratio of ethylene: (meth) acrylate: maleic anhydride of 10 to 95:50 to 1: 0.01 to 10. Item 7. The aqueous adhesive according to any one of Items 1 to 6.
8. The aqueous adhesive according to any one of claims 1 to 7, wherein the ethylene- (meth) acrylate-maleic anhydride copolymer is contained in two types in a weight ratio of 1:99 to 99: 1.
9. The water-based adhesive according to any one of claims 1 to 8, further comprising a basic compound.
10. The aqueous adhesive according to any one of claims 1 to 9, further comprising an adhesive resin.
11. The aqueous adhesive according to any one of claims 1 to 10, wherein the aqueous adhesive contains a dispersoid having a particle size (based on number) of 0.01 to 1.0 µm.
12. The aqueous adhesive according to any one of claims 1 to 11, further comprising a polyurethane resin or a water-insoluble polyurethane resin.
13. Furthermore, it contains a terpene resin selected from the group consisting of a terpene polymer, a terpene phenol, a β-pinene polymer, an aromatic modified terpene polymer, an α-pinene polymer, and a terpene hydrogenated resin. The water-based adhesive according to any one of 12 above.
14. Further, it contains a polyurethane resin and a terpene resin selected from the group consisting of a terpene polymer, a terpene phenol, a β-pinene polymer, an aromatic modified terpene polymer, an α-pinene polymer and a terpene hydrogenated resin. The water-based adhesive according to any one of claims 1 to 11.
15. The water-based adhesive according to any one of claims 1 to 11, further comprising a polyurethane resin and terpene phenol or a water-insoluble polyurethane resin and terpene phenol.
16. The aqueous adhesive according to any one of claims 1 to 15, further comprising an isocyanate.
17. Furthermore, it contains an isocyanate selected from the group consisting of diphenylmethane diisocyanate (MDI), tolylene diisocyanate (TDI), hexamethylene diisocyanate (HDI), xylene diisocyanate (XDI) and oligomers or polymers thereof. The water-based adhesive according to any one of the above.
18. An ethylene- (meth) acrylate-maleic anhydride copolymer is obtained by polymerization, and then the ethylene- (meth) acrylate-maleic anhydride copolymer is dispersed in an aqueous medium and then obtained by an emulsification method. The water-based adhesive according to any one of claims 1 to 17.