JPH11310764A - Adhesive and laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an adhesive which is excellent in adhesive strength in the normal state or under heating or after repeated cooling and heating by incorporating an aq. dispersion of an ethylene/8-12C vinyl carbonylate copolymer, an aq. dispersion of an ethylene/vinyl acetate copolymer, and a tackifier in a specified solid content ratio into the same. SOLUTION: This adhesive contains an aq. dispersion of (A) a copolymer formed from 5-50 wt.% ethylene and 50-95 wt.% 8-12C vinyl carbonylate (e.g. vinyl laurate) and having a glass transition temp. of -40 to -5 deg.C; an aq. dispersion of (B) a copolymer formed from 5-40 wt.% ethylene and 60-95 wt.% vinyl acetate and having a glass transition temp. of -10 to 25 deg.C; and (C) a tackifier having a softening point of 100-150 deg.C (e.g. a stabilized rosin ester) in a wt. ratio of A/B of (10/90)-95/5) and in a wt. ratio of (A+B)/C of (100/5)-(100/200).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive excellent in normal adhesive strength, heat resistant adhesive strength, and cold / hot adhesive strength, particularly to an adhesive useful for plastics or wood and a laminated structure using the same.

[0002]

2. Description of the Related Art Conventionally, acrylic ester (co) polymer emulsions,
An aqueous emulsion having a low glass transition temperature and a high tackiness such as an ethylene-vinyl acetate-acrylate copolymer emulsion and an ethylene-tertiary carboxylate vinyl ester copolymer emulsion has been used. It is used in large quantities in applications. However, these aqueous emulsions, although high in tackiness, are often lacking in cohesive strength and heat resistance,
In many cases, practically sufficient adhesion cannot be achieved depending on applications requiring heat resistance, repetition of cooling and heating, and the form (thickness, etc.) of the polyolefin. For example, in the bonding of polyolefin / wood material, when the thickness of the polyolefin is small, the stress on deformation due to the temperature and the like of the polyolefin is small, so that the effect on the bonding is small. For example, the degree of deformation of the polyolefin itself is small, so that the influence on the adhesion is small. However, in the case of bonding a polyolefin that is significantly deformed by heat or the like and that is relatively thick enough to apply stress to the adhesive layer, there is a case where the end of the polyolefin is peeled off from a wood material that is less deformed and floats.

[0003] In order to solve these problems, a method of introducing a crosslinking group into an aqueous emulsion or a method of blending an adhesive emulsion having a low glass transition temperature with an aqueous emulsion having a relatively high glass transition temperature is used. Furthermore, a method of adding a tackifier (tackifier) to these aqueous emulsions has been attempted, and some of them exhibit performances substantially close to required levels. However, in the case where the polyolefin is greatly deformed by heat or the like as described above and is relatively thick enough to apply stress to the adhesive layer, the required level is particularly high, and at present it has not been satisfied.

[0004]

SUMMARY OF THE INVENTION Under such circumstances, the present invention provides an adhesive which does not have the above-mentioned problems and which is excellent in normal adhesive strength, heat resistant adhesive strength, and cold / hot repeated adhesive strength, especially for plastics. Another object is to provide an adhesive useful for wood materials. Another object of the present invention is to provide a laminated structure which has little thermal deformation and does not peel off at the end and has excellent interlayer adhesion.

[0005]

The object of the present invention is to provide an aqueous dispersion comprising (A) a copolymer composed of a monomer unit mainly composed of a vinyl ester of ethylene and a carboxylic acid having 8 to 12 carbon atoms. Wherein the total amount of ethylene units and vinyl ester units of a carboxylic acid having 8 to 12 carbon atoms in the copolymer constituting the dispersoid is 90% by weight or more, and the weight ratio is ethylene units / carbon number 8-12 vinyl ester of carboxylic acid ethylene unit = 5 / 95-50 / 50
And (B) an aqueous dispersion containing a copolymer composed of a monomer unit mainly composed of ethylene and vinyl acetate as a dispersoid, and an aqueous dispersion having a glass transition temperature of −40 ° C. to −5 ° C. The total amount of ethylene units and vinyl acetate units in the copolymer constituting the dispersoid is 95% by weight or more, and the weight ratio is expressed as ethylene units / vinyl acetate units =
5/95 to 40/60, and the glass transition temperature is −
An aqueous dispersion having a temperature of 10 to 25 ° C, and (C) a softening point of 1
(A) / (B) = 10 / 90-95 / 5, Δ (A) +
(B) Achieved by providing an adhesive wherein｝ / (C) = 100/5 to 100/200, and by providing a laminated structure in which a plastic and a wood material are laminated via the adhesive. Is done.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The adhesive of the present invention has a dispersoid as a component (A) a copolymer comprising a monomer unit mainly composed of ethylene and a vinyl ester of a carboxylic acid having 8 to 12 carbon atoms. In the aqueous dispersion, the total amount of the ethylene unit and the vinyl ester unit of the carboxylic acid having 8 to 12 carbon atoms in the copolymer constituting the dispersoid is 90% by weight or more, and the weight ratio is ethylene unit. / Vinyl ester of carboxylic acid having 8 to 12 carbon atoms ethylene unit = 5 / 95-
50/50, and the glass transition temperature is −40 ° C. to −
Contains an aqueous dispersion at 5 ° C. Here, carbon number 8 ~
The vinyl ester of a carboxylic acid having 12 is not particularly limited, but vinyl 2-ethylhexanoate having an average carbon number of 1
0 tertiary vinyl carboxylate (VeoVa10: trade name of Shell), vinyl laurate and the like. Above all, a tertiary vinyl carboxylate having an average carbon number of 10 is preferably used.

[0007] The component (A) of the present invention comprises ethylene and carbon number 8
It is necessary that a copolymer composed of monomer units mainly composed of a vinyl ester of a carboxylic acid of (1) to (12) be a dispersoid, and that their proportion in the copolymer constituting the dispersoid be 90% by weight or more. And preferably at least 92% by weight. If the proportion is less than 90%, the adhesive of the present invention does not exhibit sufficient normal state adhesiveness and cold and hot repeated adhesiveness. In the dispersoid in the component (A), the weight ratio of the ethylene unit and the vinyl ester unit of the carboxylic acid having 8 to 12 carbon atoms needs to be 5/95 to 50/50, preferably 8/92. ４０40/60. When the ethylene unit is less than 5% by weight, the adhesive of the present invention is inferior in heat resistance and the like. Also, if the ethylene unit is 50
If the amount is more than 10% by weight, it is practically difficult to produce, and the adhesive of the present invention has a poor balance of normal adhesiveness, heat-resistant adhesiveness, cold-heat adhesiveness and the like. Further, the glass transition temperature of the dispersoid in the component (A) needs to be from -40C to -5C, and preferably from -37C to -8C. When the glass transition temperature is lower than −40 ° C., the adhesive of the present invention is inferior in heat resistance and the like, and when it is higher than −5 ° C., the normal state adhesiveness and the cold / hot repetition adhesiveness are inferior.

[0008] The dispersoid of the component (A) of the present invention is a copolymer comprising a monomer unit mainly composed of ethylene and a vinyl ester of a carboxylic acid having 8 to 12 carbon atoms. A monomer other than ethylene and a vinyl ester of a carboxylic acid having 8 to 12 carbon atoms other than ethylene or a vinyl ester of a carboxylic acid having 8 to 12 carbon atoms may be used. Examples of copolymerizable monomers include olefins such as propylene and isobutylene; halogenated olefins such as vinyl chloride, vinyl fluoride, vinylidene chloride, and vinylidene fluoride; vinyl esters such as vinyl formate, vinyl acetate, and vinyl propionate; Acrylic esters such as methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, 2-hydroxyethyl acrylate; methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-methacrylic acid Methacrylic esters such as ethylhexyl, dodecyl methacrylate, 2-hydroxyethyl methacrylate, and glycidyl methacrylate; β-unsaturated dicarboxylic esters such as dibutyl maleate and dioctyl maleate; Dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate or quaternary products thereof; further, acrylamide, methacrylamide, N-methylolacrylamide, N, N-dimethylacrylamide, acrylamide-2-methylpropanesulfonic acid or its sodium salt Acrylamide monomers such as acrylic acid, methacrylic acid, maleic acid,
Unsaturated carboxylic acids such as fumaric acid, crotonic acid and itaconic acid; polyfunctional crosslinkable monomers such as diallyl phthalate, triallyl cyanurate and ethylene glycol di (meth) acrylate; N-vinylpyrrolidone; And the like.

The aqueous dispersion as the component (A) of the present invention comprises:
Surfactants or protective colloids, as well as surfactants /
It is obtained by pressure emulsion polymerization in combination with a protective colloid. As the surfactant, conventionally known anionic,
Cationic, nonionic, amphoteric surfactants can be used, and as protective colloids, polyvinyl alcohol, hydroxyethylcellulose, maleic anhydride-
An isobutylene copolymer or the like is generally used. Among them, polyvinyl alcohol is preferred as the protective colloid, and the average degree of polymerization is 100 to 4000 and the degree of saponification is 60 to 1
In addition to those having a molar ratio of 00 mol%, carboxyl groups, sulfonic groups, cationic groups, thiol groups, silanol groups,
Those having a functional group such as an amino group can also be used.

As the polymerization initiator, water-soluble peroxides and persulfates such as hydrogen peroxide, potassium persulfate and ammonium persulfate are used, and oil-soluble peroxides and azo compounds can also be used. Further, a redox initiator combining these and a reducing agent such as ferrous ion, tartaric acid, Rongalite, and sodium bisulfite can be used. The polymerization method includes a batch charging method in which the monomers are added to the polymerization system in a lump, a sequential addition method in which the monomers are continuously or intermittently added to the polymerization system, and emulsification of the monomers in advance with an aqueous solution of a surfactant or a protective colloid. In addition, an emulsion addition method of adding the mixture continuously or intermittently can be adopted.

The adhesive of the present invention is an aqueous dispersion containing, as a dispersoid, a copolymer comprising monomer units mainly composed of ethylene and vinyl acetate as a component (B). The total amount of ethylene units and vinyl acetate units in the polymer is 95% by weight or more, the weight ratio is ethylene units / vinyl acetate units = 5/95 to 40/60, and the glass transition temperature is -10. Contains an aqueous dispersion at 25 ° C. The component (B) of the present invention uses a copolymer composed of monomer units mainly composed of ethylene and vinyl acetate as a dispersoid, and their proportion in the copolymer constituting the dispersoid is 95% by weight or more. And it is preferably at least 96% by weight. When the proportion is less than 95%, the adhesive of the present invention does not exhibit sufficient heat resistance. In the dispersoid in the component (B), the weight ratio of ethylene units to vinyl acetate units is from 5/95 to 40/60.
And preferably from 8/92 to 30 /
70. When the ethylene unit is less than 5% by weight, the adhesive of the present invention is inferior in normal-state adhesiveness and adhesiveness under repetition of heat and cold, and when the ethylene unit exceeds 40% by weight, production is substantially difficult. In addition, the adhesive of the present invention has poor heat resistance. Further, the glass transition temperature of the dispersoid in the component (B) needs to be from -10C to 25C, and preferably from -8C to 15C. When the glass transition temperature is lower than −10 ° C., the heat-resistant adhesiveness of the adhesive of the present invention is inferior, and when it is higher than 15 ° C., the normal state adhesiveness and the cold / hot repetitive adhesiveness are inferior.

The dispersoid of the component (B) of the present invention is a copolymer composed of monomer units mainly composed of ethylene and vinyl acetate, but not more than 5% by weight, other than ethylene and vinyl acetate. What copolymerized the monomer may be used. Examples of copolymerizable monomers include olefins such as propylene and isobutylene; halogenated olefins such as vinyl chloride, vinyl fluoride, vinylidene chloride, and vinylidene fluoride; vinyl formate, vinyl propionate, and vinyl 2-ethylhexanoate; Vinyl laurate, vinyl esters such as a vinyl ester of a tertiary carboxylic acid having an average of 10 carbon atoms; acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate; Acrylates such as 2-hydroxyethyl acrylate; methyl methacrylate, ethyl methacrylate, butyl methacrylate,
Methacrylates such as 2-ethylhexyl methacrylate, dodecyl methacrylate, 2-hydroxyethyl methacrylate, and glycidyl methacrylate; α, β-unsaturated dicarboxylic esters such as dibutyl maleate and dioctyl maleate; dimethylaminoethyl acrylate ,
Dimethylaminoethyl methacrylate or a quaternary compound thereof; further, acrylamide, methacrylamide,
Acrylamide monomers such as N-methylolacrylamide, N, N-dimethylacrylamide, acrylamide-2-methylpropanesulfonic acid or its sodium salt; acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, itaconic acid, etc. An unsaturated carboxylic acid;
Polyfunctional crosslinkable monomers such as diallyl phthalate, triallyl cyanurate, and ethylene glycol di (meth) acrylate; N-vinylpyrrolidone; and other vinyl compounds.

The aqueous dispersion as the component (B) of the present invention comprises:
Surfactants or protective colloids, as well as surfactants /
It is obtained by pressure emulsion polymerization in combination with a protective colloid. As the surfactant, conventionally known anionic,
Cationic, nonionic, amphoteric surfactants can be used, and as protective colloids, polyvinyl alcohol, hydroxyethylcellulose, maleic anhydride-
An isobutylene copolymer or the like is generally used. Among them, polyvinyl alcohol is preferred as the protective colloid, and the average degree of polymerization is 100 to 4000 and the degree of saponification is 60 to 1
In addition to those having a molar ratio of 00 mol%, carboxyl groups, sulfonic groups, cationic groups, thiol groups, silanol groups,
Those having a functional group such as an amino group can also be used.

As the polymerization initiator, water-soluble peroxides and persulfates such as hydrogen peroxide, potassium persulfate and ammonium persulfate are used, and oil-soluble peroxides and azo compounds can also be used. Further, a redox initiator combining these and a reducing agent such as ferrous ion, tartaric acid, Rongalite, and sodium bisulfite can be used. The polymerization method includes a batch charging method in which the monomers are added to the polymerization system in a lump, a sequential addition method in which the monomers are continuously or intermittently added to the polymerization system, and emulsification of the monomers in advance with an aqueous solution of a surfactant or a protective colloid. In addition, an emulsion addition method of adding the mixture continuously or intermittently can be adopted.

The adhesive of the present invention contains a tackifier having a softening point of 100 to 150 ° C. as the component (C). The components of the tackifier include various types, but are not particularly limited as long as the softening point (ring and ball method) is 100 to 150 ° C. Specific examples of the tackifier include rosin esters such as stabilized rosin esters, purified rosin esters, and polymerized rosin esters; terpene-based resins such as terpene-phenol resins, terpene polymers, and terpene-aromatic copolymers; and aliphatic. (C5 polymer), Aromatic (C9 polymer), C5 / C
Examples thereof include petroleum resin-based resins such as 9-copolymer, and among them, rosin ester-based resins are preferable. These tackifiers may be emulsified by forcibly emulsifying the tackifier resin in the components (A) and (B). However, the tackifier may be miscible with the components (A) and (B). (C) It is preferable to use as an aqueous dispersion liquid which is forcibly emulsified using various emulsifiers.

The adhesive of the present invention comprises the above (A), (B),
It is mainly composed of the component (C), but its mixing ratio is (A) / (B) = 10/90 to 95/5 in terms of solid content weight ratio,
{(A) + (B)} / (C) = 100/5 to 100/2
00, preferably (A) /
(B) = 20 / 80-90 / 10, {(A) + (B)}
/ (C) = 100/10 to 100/200, more preferably (A) / (B) = 30/70 to 70/30,
{(A) + (B)} / (C) = 100 / 30-100 /
150. When the component (A) is less than (A) / (B) = 10/100, the adhesive of the present invention is inferior in normal adhesion and cold / hot repetitive adhesion, and when the component (A) is more than 90/10. In addition, the adhesive of the present invention is inferior in heat-resistant adhesiveness and cold-heat adhesiveness. Also, ｛(A) +
(B) When the component (C) is less than 100 // 5, or {(A) + (B)} / (C) = 10
When the content of the component (C) is more than 0/200, the adhesiveness of the present invention cannot be balanced in normal adhesiveness, heat resistant adhesiveness, and cold / hot repeated adhesiveness.

The adhesive of the present invention is particularly useful for plastics and wood materials. Here, examples of the plastic include thermoplastic resins such as polyolefin, polyester, polyamide, polyvinyl chloride, and polystyrene. Of these, polyolefins, especially polypropylene and polyethylene, were difficult to provide excellent adhesion with conventional water-based adhesives.However, according to the adhesive of the present invention, excellent adhesiveness was obtained. Can be provided. Also, as a wood material,
Wood, plywood, fiberboard, particleboard,
MDF (Medium Density Fiberbo)
ard), cellulosic paper, interleaf paper and the like.

Through the adhesive of the present invention, plastic,
In particular, by laminating polyolefin and a woody material, a laminated structure having less thermal deformation and excellent interlayer adhesion can be obtained. In addition, even when a thick sheet, for example, a sheet having a thickness of 0.3 to 20 mm, particularly 0.5 to 10 mm is used as a polyolefin and laminated with a woody material, the sheet is less thermally deformed, and the sheet has a lower thermal deformation. The end does not peel off and no floating occurs.

Further, a composition obtained by blending a plastic, especially polyolefin, with an inorganic reinforcing agent such as mica,
By laminating this and the woody material via the adhesive of the present invention, it is possible to obtain a laminated structure having less thermal deformation and further excellent interlayer adhesion. At this time, the content of the inorganic reinforcing agent such as mica was 1 to the total weight.
It is 0 to 60% by weight, preferably 20 to 50% by weight.

The adhesive of the present invention is particularly useful as an interlayer adhesive for the above-mentioned laminated structure of plastic and wood material, but other laminated structures, for example, plastic / inorganic materials (concrete, mortar, etc.) It is also useful as an interlayer adhesive for a laminated structure of a plastic / inorganic material or the like containing an inorganic reinforcing agent such as mica.

The adhesive of the present invention may contain a conventionally known aqueous emulsion, a conventionally known anionic, nonionic, cationic or amphoteric surfactant, a starch, Modified starch, oxidized starch, sodium alginate, carboxymethylcellulose, methylcellulose, hydroxymethylcellulose,
Water-soluble polymer compounds such as maleic anhydride / isobutene copolymer, maleic anhydride / styrene copolymer, maleic anhydride / methyl vinyl ether copolymer, urea / formalin resin, urea / melamine / formalin resin, phenol / formalin A thermosetting resin such as a resin can also be used together. Further, the adhesive of the present invention includes fillers such as clay, kaolin, talc, calcium carbonate, and wood flour; fillers such as flour; pigments such as titanium oxide; and other preservatives, rust inhibitors, and defoamers Various additives such as the above can also be appropriately added.

The solid content of the adhesive of the present invention is from 20 to 7
5% by weight is preferred. If the solid concentration is lower than 20% by weight, there is a problem that the initial adhesive strength is not sufficiently exhibited,
If it exceeds 75% by weight, there is a problem that the viscosity of the adhesive increases and the stability decreases.

The adhesive of the present invention can be applied by any method such as hand coating, brush coating, roll coating, spray coating, and the like. Will be

[0024]

Next, the present invention will be described in more detail with reference to Examples and Comparative Examples. In the following Examples and Comparative Examples, “parts” and “%” mean on a weight basis unless otherwise specified.

(Evaluation of Adhesive Property) Base material: mica reinforced polypropylene sheet (mica content 40% by weight based on total weight) Thickness 0.8 mm MDF board thickness 18 mm Adhesive base material size: 180 mm × 275 mm Adhesion method: Apply adhesive on MDF board by brush.
0 g was uniformly applied, and a mica-reinforced polypropylene sheet was stuck at an open time of about 5 minutes, and the air was released by holding the sheet lightly by hand. Thereafter, it was pressed (at 20 ° C. and 65% RH) for 2 days with a load of 5 kg, decompressed, and cured for 7 days (20 ° C. and 65% RH).・ Adhesiveness evaluation method: ・ End condition: The cured body was cured at 80 ° C. for 2 hours at -1.
Three heat cycles of 0 ° C. for 2 hours were performed, and the bonded end was visually observed. -Room temperature adhesive strength: Further, the state when the mica-reinforced polypropylene sheet was forcibly peeled off after the heat cycle was evaluated (20 ° C). ◎: Adhesive strength is very good ○: Adhesive strength is large, MDF material is broken △: Adhesive strength is not broken, MDF material is not damaged ×: Adhesive strength is small, peeling with little force applied ・ 80 ° C adhesive strength: Furthermore, the state when the mica-reinforced polypropylene sheet was forcibly peeled off at 80 ° C. after the heat cycle was evaluated. ：: Very good adhesive strength ○: Great adhesive power ×: Low adhesive strength, peeled off with little force

Example 1 (A) Ethylene-VeoVa10-vinyl acetate copolymer emulsion (Em-1: ethylene / VeoVa10 / vinyl acetate = 20/75/5 wt%, stabilizer PV
A / Nonionic emulsifier, Tg = -25 ℃, solid content concentration 50%) 90 parts,
(B) Ethylene-vinyl acetate copolymer emulsion ｛Em-
2: Ethylene / vinyl acetate = 20 / 80wt%, stabilizer PVA, Tg = 0 ° C, solid content concentration 55%｝ 10 parts, (C) tackifier (Rosin emulsion: Arakawa Chemical superester E-625, softening) Point 125 ° C, solids concentration 50
%) To prepare an adhesive. The adhesiveness was evaluated using this adhesive. Table 1 shows the results.

Example 2 The procedure of Example 1 was repeated except that Em-1 was changed to 80 parts and Em-2 was changed to 20 parts. Table 1 shows the results.

Example 3 Example 1 was repeated except that Em-1 was changed to 85 parts and Em-2 was changed to 15 parts. Table 1 shows the results.

Example 4 In Example 1, 50 parts of Em-1, 50 parts of Em-2 and 50 parts of a tackifier were blended to prepare an adhesive. The adhesiveness was evaluated using this adhesive. Table 1 shows the results.

Example 5 In Example 4, 30 parts of Em-1, 70 parts of Em-2 and 80 parts of a tackifier were mixed to prepare an adhesive. The adhesiveness was evaluated using this adhesive. Table 1 shows the results.

Example 6 The procedure of Example 4 was repeated, except that Em-1 was changed to 60 parts and Em-2 was changed to 40 parts. Table 1 shows the results.

Example 7 The procedure of Example 4 was repeated, except that the tackifier was changed to 100 parts. Table 1 shows the results.

Example 8 The procedure of Example 4 was repeated, except that the tackifier was changed to 30 parts. Table 1 shows the results.

Example 9 Em-1 in Example 4 was replaced with an ethylene-VeoVa10-2-vinyl ethylhexanoate-vinyl acetate copolymer emulsion (E
m-3: ethylene / VeoVa10 / 2-ethylhexanoate / vinyl acetate = 20/60/15
/ 5 wt%, stabilizer PVA / nonionic emulsifier, Tg = −32 ° C., solid content concentration 50%). Table 1 shows the results.

Example 10 Em-2 in Example 4 was replaced with an ethylene-vinyl acetate copolymer emulsion (Em-4: ethylene / vinyl acetate = 12/88 wt%, stabilizer
PVA, Tg = 12 ° C., solid content concentration 55%). Table 1 shows the results.

Example 11 The same procedure as in Example 4 was carried out except that, instead of using the tackifier in Example 4, Rossin Emulsion Sulfur Ester E-730-55 (softening point 125 ° C., solid content concentration 55%) manufactured by Arakawa Chemical Co., Ltd. was used. I made it. Table 1 shows the results.

Comparative Example 1 An adhesive was prepared by mixing 10 parts of a tackifier with 100 parts of Em-1. Using this adhesive, the above-mentioned adhesiveness was evaluated in the same manner as in Example 1 except that Em-2 was not used. Table 1 shows the results.

Comparative Example 2 The procedure of Example 1 was repeated, except that 10 parts of Em-1 and 90 parts of Em-2 were used. Table 1 shows the results.

Comparative Example 3 The procedure of Example 4 was repeated except that Em-1 was used in an amount of 100 parts and Em-2 was not used. Table 1 shows the results.

Comparative Example 4 The procedure of Example 4 was repeated, except that 10 parts of Em-1 and 90 parts of Em-2 were used. Table 1 shows the results.

Comparative Example 5 The procedure of Example 4 was repeated, except that 90 parts of Em-1 and 10 parts of Em-2 were used. Table 1 shows the results.

Comparative Example 6 In Example 4, an ethylene-vinyl acetate copolymer emulsion (Em-5: ethylene / vinyl acetate = 35/65 wt.) Was used instead of Em-1.
%, Stabilizer PVA, Tg = -25 ° C., solid content concentration 55%). Table 1 shows the results.

Comparative Example 7 In Example 4, an ethylene-VeoVa10-vinyl acetate copolymer emulsion (Em-6: ethylene / VeoVa10 / vinyl acetate = 20/60/20 wt%, stabilizer PVA) was used in place of Em-1. / Nonionic emulsifier, Tg =-
The procedure was the same as that of Example 4 except that 16 ° C. and a solid concentration of 50% were used. Table 1 shows the results.

Comparative Example 8 In Example 4, an ethylene-vinyl acetate copolymer emulsion (Em-7: ethylene / vinyl acetate = 3/97 wt%,
Example 4 was repeated except that a stabilizer (PVA, Tg = 26 ° C, solid content concentration 55%) was used. Table 1 shows the results.

COMPARATIVE EXAMPLE 9 Instead of the tackifier in Example 4, the composition was changed to Arakawa Chemical's Rossin Emulsion Supharester E-650 (softening point: 160 ° C., solid content: 50%).
%) Except that (%) was used. Table 1 shows the results
Shown in

Comparative Example 10 The procedure of Example 4 was repeated except that 200 parts of the tackifier was used. Table 1 shows the results.

Comparative Example 11 Example 4 was repeated except that no tackifier was used.
Same as. Table 1 shows the results.

COMPARATIVE EXAMPLE 12 In place of the tackifier in Example 4, the composition was changed to Arakawa Chemical's Rosin Emulsion Sulfur Ester A-75 (softening point of 75 ° C., solid content of 50%).
%) Except that (%) was used. Table 1 shows the results
Shown in

[0049]

[Table 1]

Em-1: ethylene / VeoVa10 / vinyl acetate =
20/75 / 5wt%, stabilizer PVA / nonionic emulsifier, Tg
= -25 ° C, solid content concentration 50%, Em-2: ethylene / vinyl acetate = 20 / 80wt%, stabilizer P
VA, Tg = 0 ° C., solid content concentration 55% Em-3: ethylene / VeoVa10 / 2-vinyl ethylhexanoate / vinyl acetate = 20/60/15/5 wt%, stabilizer PVA / nonionic emulsifier, Tg = -32 ° C, solid content concentration 50%, Em-4: ethylene / vinyl acetate = 12 / 88wt%, stabilizer P
VA, Tg = 12 ° C, solid content concentration 55% Em-5: Ethylene / vinyl acetate = 35 / 65wt%, stabilizer P
VA, Tg = −25 ° C., solid content concentration 55% Em-6: ethylene / VeoVa10 / vinyl acetate = 20/60/2
0% by weight, stabilizer PVA / nonionic emulsifier, Tg: -16 ° C,
Solid content concentration 50wt% Em-7: ethylene / vinyl acetate = 3 / 97wt%, stabilizer PV
A, Tg: 26 ° C., solid content 55% by weight, super ester E-625 (softening point 125 ° C., solid content 50%) super ester E-730-55 (softening point 125 ° C., solid content 55)
%) SUPER ESTER E-650 (softening point 160 ° C, solid content 50%) SUPER ESTER A-75 (softening point 75 ° C, solid content 50%)

[0051]

The adhesive of the present invention is extremely excellent in normal adhesive strength, heat resistant adhesive strength and cold / hot repeated adhesive strength, and is particularly useful as an adhesive for plastics and wood materials. Further, the laminated structure laminated via the adhesive of the present invention, particularly the laminated structure obtained by laminating a plastic and a wooden material, has little thermal deformation and extremely excellent interlayer adhesion.

Claims (8)

[Claims] 1. An aqueous dispersion comprising, as a dispersoid, (A) a copolymer comprising a monomer unit mainly composed of a vinyl ester of ethylene and a carboxylic acid having 8 to 12 carbon atoms, wherein the aqueous dispersion comprises Ethylene units and carbon number of 8 to 8 in the copolymer
The total amount of vinyl ester units of 12 carboxylic acids is 90
% By weight or more, and the weight ratio is ethylene units / vinyl ester of carboxylic acid having 8 to 12 carbon atoms, ethylene units = 5/95 to 50/50, and the glass transition temperature is -40 ° C to -5 ° C. An aqueous dispersion comprising (B) a copolymer comprising a monomer unit mainly composed of ethylene and vinyl acetate as a dispersoid, wherein ethylene units occupy in the copolymer constituting the dispersoid And the total amount of vinyl acetate units is 95% by weight or more, and the weight ratio thereof is ethylene units / vinyl acetate units = 5/95 to 40/60,
And an aqueous dispersion having a glass transition temperature of -10 to 25 ° C, and a tackifier having a softening point of 100 to 150 ° C and a solid content weight ratio of (A) / (B) = 10/90.
９５95/5, {(A) + (B)} / (C) = 100/5
An adhesive that is １００100/200. 2. The solid content ratio is (A) / (B) = 20/80.
９５95/5, {(A) + (B)} / (C) = 100/1
2. The adhesive according to claim 1, wherein the amount is from 0 to 100/200. 3. The solid content ratio is (A) / (B) = 30/70.
７０70/30, {(A) + (B)} / (C) = 100 /
The adhesive according to claim 1, wherein the adhesive is 30 to 100/150. 4. The adhesive according to claim 1, which is a plastic adhesive. 5. The adhesive according to claim 1, which is an adhesive for polyolefin. 6. The adhesive according to claim 1, which is an adhesive for wood materials. 7. A laminated structure obtained by laminating a plastic and a wooden material via the adhesive according to claim 1, 2 or 3. 8. A laminated structure in which a woody material and a plastic containing an inorganic reinforcing agent are laminated via the adhesive according to claim 1, 2 or 3.