JP2735455B2 - Aqueous adhesive composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aqueous pressure-sensitive adhesive composition, and more particularly to a water-based pressure-sensitive adhesive composition having excellent adhesiveness and holding power and forming a film excellent in adhesiveness to a surface of low polarity such as polyolefin. Water-based adhesive composition.

[0002]

2. Description of the Related Art Conventionally, it has been known to use a copolymer aqueous dispersion obtained by emulsion polymerization of a vinyl monomer for forming a pressure-sensitive adhesive film or an adhesive film. When the adherend has a surface with low polarity such as polyethylene or polypropylene, there is a problem that adhesion is poor.

[0003]

In order to improve the adhesive strength, the molecular weight of the resin of the aqueous dispersion is reduced by using a chain transfer agent or the like, or a resin having a low glass transition point is used.
Further, there is a method of blending a tackifier. However, according to these methods, although the adhesive force is improved, there is a problem that the holding force of the adhesive is reduced.

[0004] A film which solves the above-mentioned conventional problems, improves adhesion without lowering holding power, and has excellent adhesion to adherends having a surface of low polarity such as polyolefin. It is an object of the present invention to provide an aqueous adhesive composition capable of forming

[0005]

Means for Solving the Problems As a result of intensive studies, the present inventors have achieved the above object by adopting the following constitution. That is, the present invention provides, as a core layer, at least one kind of tackifier resin selected from the group consisting of (A) a rosin resin having allyl hydrogen, a terpene resin having allyl hydrogen, and a petroleum resin having allyl hydrogen. a) 0.1 to 5% by weight of a carbonyl group-containing unsaturated monomer, (b) 60 to 99.8% by weight of an alkyl ester of acrylic acid having 4 to 12 carbon atoms, (c) these unsaturated monomers 0.1 to 39.9 other unsaturated monomers copolymerizable with
(B) aqueous dispersion of resin particles having a shell layer formed of a resin obtained by emulsion polymerization of a monomer mixture consisting of at least two hydrazino groups having at least two hydrazino groups in a molecule. The adhesive composition, wherein the glass transition temperature of the shell layer of the aqueous dispersion is −85 to −30 ° C.
Aqueous adhesive composition, characterized in that:

As the tackifier resin used for adjusting the resin core layer of the aqueous resin dispersion (A) in the present invention, a resin having allyl hydrogen can be mainly used. Examples of the resin having allyl hydrogen include a rosin resin having allyl hydrogen, a terpene resin having allyl hydrogen, and a petroleum resin having allyl hydrogen.

The rosin resins having allyl hydrogen include, for example, gum rosin, tall oil rosin, wood rosin, abietic acid isolated from these rosins, alkali metal salts of abietic acid, abietic acid and polyhydric alcohol (for example, ethylene). Glycol, glycerin, pentaerythritol, trimethylolpropane, etc.), various modified rosins, and various rosin derivatives.

These products are sold by Harima Chemicals, Inc. under the trade name Hariestar. Particularly preferred among these rosin-based resins having allyl hydrogen are those represented by the general formula

[0009]

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And a derivative thereof. As the terpene resin having allyl hydrogen, for example,

[0011]

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And terpene / phenol copolymer resins. The petroleum resin having allyl hydrogen is a C5 fraction (isoprene, cyclopentadiene, 1,3-pentadiene, 1-pentene, 2-pentene,
A resin obtained by copolymerizing pentene, dicyclopentadiene, 1,3-pentadiene, etc.) and a C6-C11 fraction (main component is C9 fraction such as indene, styrene, methylindene, α-methylstyrene). Polymerized resin, and C
Examples thereof include resins obtained by copolymerizing a 5-C11 fraction.

The "allyl hydrogen" described in this specification
Is the R of the following allyl skeleton¹~ R ^ThreeJoined to
Refers to hydrogen. Therefore,

[0014]

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The (a) carbonyl group-containing unsaturated monomer used for preparing the resin shell layer of the aqueous dispersion (A) in the present invention includes at least one carbonyl group (carboxyl group) in the molecule. And a polymerizable double bond-containing unsaturated monomer containing a carbonyl group based on a carboxylic acid ester group, that is, at least one carbonyl group based on an ald group or a keto group in the molecule. It is an unsaturated monomer having a polymerizable double bond.

Specific examples of the unsaturated monomer containing a carbonyl group include, for example, acrolein, diacetone acrylamide, formylstyrene, preferably
Vinyl alkyl ketone having 7 carbon atoms (eg, vinyl methyl ketone, vinyl ethyl ketone, vinyl isobutyl ketone, etc.), diacetone acrylate, acetonyl acrylate, diacetone methacrylate, 2-acetone
Examples thereof include hydroxypropyl acrylate-acetyl acetate, butanediol-1,4-acrylate-acetyl acetate, and acryl (or methacryl) oxyalkylpropanal represented by the following general formula (1).

[0017]

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Wherein R ¹ is H or CH ₃ , R ² is H or an alkyl group having 1 to ³ carbon atoms, and R ³ is 1 to ³
An alkyl group having 3 carbon atoms, and R ⁴ is 1-
Indicate an alkyl group having 4 carbon atoms. Among these unsaturated monomers containing a carbonyl group, acrolein, diacetone acrylamide and vinyl methyl ketone are preferred. The unsaturated monomer having a carbonyl group may be used alone or in combination of two or more. The amount of the unsaturated monomer having a carbonyl group used is 0.1 to 5.0 in all the unsaturated monomers.
% By weight, preferably 0.1 to 1.0% by weight. Outside this range, the holding power as an adhesive is inferior.

The (b) alkyl ester of acrylic acid having 4 to 12 carbon atoms used for preparing the resin shell layer of the aqueous dispersion (A) in the present invention includes, for example, n
-Butyl acrylate, isobutyl acrylate, hexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, nonyl acrylate, isononyl acrylate and the like. In particular, it is preferable to use n-butyl acrylate or 2-ethylhexyl acrylate because the balance between the adhesive strength and the holding power of the adhesive composition is improved.

(B) The alkyl ester of acrylic acid having 4 to 12 carbon atoms is used to develop the initial adhesiveness in the adhesive composition, and the amount of the alkyl ester used is the total amount of the unsaturated monomer. The content is 60 to 99.8% by weight. If the amount is less than 60% by weight, the copolymer resin becomes hard and the initial adhesiveness decreases.

(C) Other unsaturated monomers copolymerizable with these unsaturated monomers used for preparing the resin shell layer of the aqueous dispersion (A) in the present invention include, for example, Lower alkyl esters of acrylic acid such as methyl acrylate, ethyl acrylate and n-propyl acrylate; lower alkyl esters of methacrylic acid such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate and butyl methacrylate; styrene, α -Methylstyrene, acrylonitrile, methacrylonitrile, vinyl acetate, vinyl propionate, ethylene, vinyl chloride,
Vinylidene chloride; acrylamide, methacrylamide,
Unsaturated monomers having an amide group such as N-methylol acrylamide and N-methylol methacrylamide and derivatives thereof; unsaturated monomers having an epoxy group such as glycidyl acrylate and glycidyl methacrylate; acrylic acid, methacrylic acid, itaconic acid Unsaturated carboxylic acids such as hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate and hydroxybutyl methacrylate;
-Phenylmaleimide, N- (methyl) phenylmaleimide, N- (hydroxy) phenylmaleimide, N-
(Methoxy) phenylmaleimide, N-benzoic maleimide, N-methylmaleimide, N-ethylmaleimide,
Nn-propylmaleimide, N-isopropylmaleimide, Nn-butylmaleimide, N-isobutylmaleimide, Nt-butylmaleimide and the like can be mentioned.
The amount of these other unsaturated monomers used is 0.1 to 39.9% by weight based on the total amount of unsaturated monomers.

The glass transition point of the shell layer of the resin of the aqueous dispersion (A) of the present invention needs to be -85 to -30 ° C, preferably -75 to -40 ° C. If the glass transition point is too low, the holding power will decrease, and if the glass transition point is too high, the adhesion will decrease.

The aqueous dispersion (A) contains at least one tackifier resin selected from the group consisting of the above-mentioned rosin resin having allyl hydrogen, terpene resin having allyl hydrogen, and petroleum resin having allyl hydrogen. Layers and
(A) 0.1 to 5% by weight of a carbonyl group-containing unsaturated monomer, (b) 60 to 99.8% by weight of an alkyl ester of acrylic acid having 4 to 12 carbon atoms, (c) an unsaturated monomer thereof. It is an aqueous dispersion of resin particles having a shell layer of a resin obtained by emulsion polymerization of a monomer mixture comprising 0.1 to 39.9% by weight of another unsaturated monomer copolymerizable with the polymer. .

As a method for producing the aqueous dispersion (A) used for preparing the aqueous adhesive composition of the present invention, the above tackifier resin is dispersed in water in advance to form an emulsion, A monomer mixture capable of forming a shell layer is added and emulsion polymerization is performed. In addition, as a method of dispersing the tackifier resin in water, a method of dissolving the tackifier resin in a solvent, removing the solvent after emulsification in water in the presence of an emulsifier or a dispersant, or removing a small amount of solvent A method of dissolving the tackifier resin under high temperature and high pressure, emulsifying the resin in water in the presence of an emulsifier and a dispersant, and then removing the solvent is used. In the present invention, the core layer is preferably 0.1 to
20%, more preferably 1.0 to 10%. If the number of the core layers is too small, the adhesive strength of the pressure-sensitive adhesive is inferior. If the number of the core layers is too large, the holding power is inferior.

The emulsion polymerization of the monomer mixture can be easily carried out according to a conventional method. That is,
In water in the presence of a tackifier resin (an emulsifier or a dispersant may be further added if necessary), in the presence of a polymerization initiator such as potassium persulfate, Emulsion polymerization is performed under heating at 80 to 95 ° C.

As the polymerization initiator, a redox initiator using a reducing agent may be used. Further, the method of supplying the monomer may be a batch charging method, a method of sequentially adding the monomer, or a method of adding the monomer after forming the aqueous emulsion. Good. Further, a method of changing the monomer composition of the polymerization system stepwise or continuously, for example, a seed polymerization method or a power feed polymerization method can also be used.

Examples of the emulsifier used for emulsifying the tackifier resin and the monomer mixture include higher alcohol sulfates, alkylbenzene sulfonates, polyoxyethylene alkyl sulfates, and polyoxyethylene alkyl phenol ether sulfates. Anionic surfactants, such as ate salts, or various nonionic surfactants can be used. Further, a reactive emulsifier having a polymerizable double bond in the molecule may be used. Further, in some cases, a cationic surfactant can be used alone or in combination with a nonionic surfactant. The amount of the surfactant used is usually 0.2 to 10% by weight based on the total amount of unsaturated monomers.

As the dispersant used for emulsifying the tackifier resin or the monomer mixture, (a) at least one ald group or keto group and one polymerizable double 0.5% of a carbonyl group-containing monomer unit having a bond
(B) a monoolefinically unsaturated carboxylic acid unit having 3 to 5 carbon atoms, an unsaturated carboxylic acid amide unit, an N-alkyl and / or N of the unsaturated carboxylic acid amide; An alkylol derivative unit, an amino group-containing monomer unit (for example, N, N-dimethylaminoethyl methacrylate unit, N, N-diethylaminomethacrylate unit), or a monoolefinically unsaturated carboxylic acid unit. 99.5-
0.5% by weight, (c) an acrylic acid or methacrylic acid alkyl ester unit having 1 to 8 carbon atoms, a vinyl aromatic monomer unit, a vinyl halide unit, an ethylene unit, an acrylonitrile unit, a methacrylonitrile unit, A copolymer containing 0 to 70% by weight of a unit selected from the group consisting of a saturated carboxylic acid vinyl ester unit, a hydroxyl group-containing monomer unit (for example, a hydroxyethyl acrylate unit and a hydroxyethyl methacrylate unit), and a 1,3-diene unit. A coalesced or alkali neutralized product of the same copolymer may be used. When such a copolymer dispersant is used, since the dispersant component is integrated with the resin molecule by crosslinking, the resulting coating film formed by the aqueous pressure-sensitive adhesive composition of the present invention has water resistance and weather resistance. It becomes more excellent.

Next, if the hydrazine derivative (B) containing at least two hydrazino groups in the molecule is blended with the aqueous dispersion (A) obtained by the above emulsion polymerization,
The aqueous adhesive composition of the present invention is obtained. Examples of the hydrazine derivative (B) containing at least two hydrazino groups in its molecule include dicarboxylic acids which are dehydration condensates of dicarboxylic acids having 2 to 10, preferably 4 to 6 carbon atoms with hydrazine. Dihydrazide (eg, oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, glutaric acid dihydrazide, adipic acid dihydrazide, sebacic acid dihydrazide, maleic acid dihydrazide, fumaric acid dihydrazide, itaconic acid dihydrazide, etc.); having 2 to 4 carbon atoms. Aliphatic water-soluble dihydrazine (for example, ethylene-1,2-dihydrazine, propylene-1,3-dihydrazine, butylene-
1,4-dihydrazine, etc.).

Further, a polymer having a hydrazino group represented by the following general formula can also be used as the hydrazine derivative. Such a polymer having a hydrazino group is described in detail, for example, in JP-A-55-6535.

[0031]

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Wherein X is a hydrogen atom or a carboxyl group, Y is a hydrogen atom or a methyl group, and A is each unit of acrylamide, methacrylamide, acrylate, methacrylate or maleic anhydride. And B are units of a monomer copolymerizable with acrylamide, methacrylamide, acrylate, methacrylate or maleic anhydride. Further, k, m and n are numbers satisfying the following formulas: 2 mol% ≦ k ≦ 100 mol% 0 mol% ≦ (m + n) ≦ 98 mol% (k + m + n) = 100 mol% ]

The mixing ratio of the hydrazine derivative in the present invention is such that the hydrazino group is preferably 0.05 to 5 mol, more preferably 0.4 to 1.2 mol, per 1 mol of the carbonyl group in the component (A). Ratio. If the blending ratio of the hydrazine derivative is too small, crosslinking is not sufficiently performed and the holding power tends to be reduced. If the blending ratio is too large, the adhesive strength tends to decrease.

Various other components can be added to the aqueous pressure-sensitive adhesive composition of the present invention, if necessary. For example, with respect to 1 mol of a hydrazino group of a hydrazine derivative,
One or more water-soluble metal salts (e.g., zinc salt, manganese salt, cobalt salt, lead salt, etc.)
0.02 mol can be added. When these water-soluble metal salts are added, the amount of the aqueous dispersion of the carbonyl group-containing copolymer containing the hydrazine derivative (that is, the aqueous pressure-sensitive adhesive composition of the present invention) is hindered in stability. The formation of free hydrazine can be prevented, and these metal salts do not adversely affect the crosslinking reaction in the formed coating film.

Further, the aqueous adhesive composition of the present invention comprises
Other aqueous resin dispersions can be added as long as the physical properties are not impaired. For example, an aqueous resin dispersion or a urethane resin emulsion obtained by general emulsion polymerization can be added. In particular, a monomer mixture having exactly the same monomer composition as used in the production of the resin aqueous dispersion used in the preparation of the aqueous pressure-sensitive adhesive composition of the present invention, a substantially chain transfer agent Aqueous resin dispersion obtained by emulsion polymerization in a reaction system that does not contain any of the above can be added.

The aqueous adhesive composition of the present invention may further contain a dispersant, a lubricant, a defoaming agent, a solvent, a film-forming aid, a plasticizer, Various additives such as an inhibitor, a thickener, and tackifier may be added. In addition, pigments generally known in the field of compounding techniques such as adhesives and pressure-sensitive adhesives, such as calcium carbonate, talc, clay, mica powder, barite, and titanium oxide, can also be compounded.

[0037]

The present invention will be described below in more detail with reference to Examples and Comparative Examples. “Parts” and “%” in these examples indicate parts by weight and% by weight, respectively, unless otherwise specified. Example 1 Temperature controller, squirrel-type stirrer, reflux condenser, supply container,
330 parts of water in a reactor equipped with a thermometer and a nitrogen inlet tube,
And 1 part of sodium persulfate.

As a feed I, a tackifier resin emulsion (trade name: Harrier Star DS-9, manufactured by Harima Chemicals, Inc.)
OE) was prepared and charged in the reaction vessel in advance. The following were prepared as feed II. 2-ethylhexyl acrylate 1363 parts Methyl methacrylate 133 parts Vinyl acetate 64 parts Acrolein 8 parts Acrylic acid 32 parts Water 650 parts Sulfate of sodium sulfate (anionic emulsifier) of p-nonylphenol reacted with 20 mol of ethylene oxide 30 106 parts by weight aqueous solution Separately, as a feed III, an initiator solution was prepared by dissolving 12 parts of sodium persulfate in 160 parts of water.

After the inside of the reactor previously charged with the initiator solution and the feed I was replaced with nitrogen gas, 10% by weight of the feed II was added to the reactor, and the mixture was heated to 90 ° C. did. Then, 10% by weight of Feed III is injected into the reactor, and Feed II and the remainder of Feed III are removed from 3 to 3%.
The reactor was fed gradually and uniformly over 3.5 hours. After the completion of the supply, the emulsion was maintained at 90 ° C. for 1.5 hours to carry out emulsion polymerization to obtain a copolymer dispersion. The copolymer concentration of the copolymer dispersion was about 57%.

Next, 6 parts of adipic acid dihydrazide was added to the obtained aqueous resin dispersion, followed by stirring and mixing for 1 hour to obtain an aqueous pressure-sensitive adhesive composition. Examples 2 to 8 The monomer composition used in the emulsion polymerization, the type and amount of the tackifier resin used, the type of the hydrazine derivative and the amount used were changed as shown in Tables 1 and 2, and the others were the same as in Example 1. The aqueous pressure-sensitive adhesive composition was prepared according to the method described in (1).

[0041]

[Table 1]

[0042]

[Table 2]

* 1 DS-90E: Harimastar DS-90E (Rosin-based resin) manufactured by Harima Chemicals Co., Ltd. * 2 DS-110SE: Harristar DS-110SE manufactured by Harima Chemicals, Inc. (Rosin-based resin) * 3 E-625 ··· Arakawa Chemical Industry Co., Ltd. Super Ester E-625 (rosin-based resin) * 4 E-100 ··· Arakawa Chemical Industry Co., Ltd. product name Tamanoru E- 100 (terpene / phenolic resin) * 5 SE-350: trade name, manufactured by Toho Chemical Industry Co., Ltd. Himax SE-350 (petroleum resin) * 6 ADH: adipic dihydrazide * 7 SDH: sebacic dihydrazide Comparative Example 1 A temperature controller, an irrigated stirrer, a reflux condenser, a supply container,
330 parts of water in a reactor equipped with a thermometer and a nitrogen inlet tube,
And 1 part of sodium persulfate.

As a feed I, a tackifier resin emulsion (trade name: Harrier Star DS-9 manufactured by Harima Chemicals, Inc.)
OE) were prepared in 16 parts. The following were prepared as feed II. 2-ethylhexyl acrylate 1363 parts Methyl methacrylate 133 parts Vinyl acetate 64 parts Acrolein 8 parts Acrylic acid 32 parts Water 650 parts 30% by weight aqueous solution of the anionic emulsifier 106 parts Separately, as feed III, in water 160 parts An initiator solution in which 12 parts of sodium persulfate was dissolved was prepared.

The above initiator solution and feed II
After replacing the inside of the reactor charged with 0% by weight with nitrogen gas,
The mixture was heated to 90C. Next, 10% by weight of the feed III is injected into the reactor, and the feed II and the remainder of the feed III are gradually and uniformly mixed in the reactor over 3 to 3.5 hours. Supplied. After the end of the supply 1.
Emulsion polymerization was carried out at 90 ° C. for 5 hours to obtain a copolymer dispersion. The copolymer concentration of the copolymer dispersion was about 57%.
Met.

Next, 0.3 parts of sebacic acid dihydrazide and Feed I were added to the obtained aqueous resin dispersion, followed by stirring and mixing for 1 hour to obtain an aqueous pressure-sensitive adhesive composition. Comparative Examples 2 to 6 The monomer composition used for the emulsion polymerization, the type and amount of the tackifier resin used, the type of the hydrazine derivative and the amount used were changed as shown in Tables 3 and 4, and the others were as in Example 1. The aqueous pressure-sensitive adhesive composition was prepared according to the method described in (1).

Comparative Example 7 A temperature controller, an irrigated stirrer, a reflux condenser, a supply vessel,
330 parts of water in a reactor equipped with a thermometer and a nitrogen inlet tube,
And 1 part of sodium persulfate. 480 parts of a tackifier resin emulsion (trade name: Harrier Star DS-110SE, manufactured by Harima Chemicals, Inc.) was prepared as Feed I. The following were prepared as feeds II, III, and IV, respectively.

Feed II Methyl methacrylate 64 parts Acrylonitrile 64 parts Water 50 parts 30 wt% aqueous solution of the anionic emulsifier 8 parts Feed III 2-ethylhexyl acrylate 960 parts Butyl acrylate 480 parts Acrylic acid 22 parts Acrolein 10 parts Water 600 parts 30% by weight aqueous solution of the anionic emulsifier 100 parts Feed IV An initiator solution was prepared by dissolving 12 parts of sodium persulfate in 160 parts of water.

After the inside of the reaction vessel previously charged with the initiator solution and the feed I was replaced with nitrogen gas, the mixture was added to 9
Heated to 0 ° C. Then, 10% by weight of the feed II and the feed IV were gradually and uniformly fed to the reactor over 0.5 to 1 hour in parallel. Thirty minutes after the end of the supply, the remainder of Feed III and Feed IV was gradually and uniformly fed to the reactor over a period of 2.5 to 3 hours. 1.5 after the end of the supply
Emulsion polymerization was carried out at 90 ° C. for a time to obtain a copolymer dispersion. The copolymer concentration of the copolymer dispersion was about 52%.

Next, 6.0 parts of sebacic acid dihydrazide was added to the obtained aqueous resin dispersion, followed by stirring and mixing for 1 hour to obtain an aqueous pressure-sensitive adhesive composition. With respect to the applied and dried film of the aqueous pressure-sensitive adhesive compositions (copolymer resin concentration is about 57% by weight) obtained in each of the above Examples and Comparative Examples, ball tack, adhesion test and holding power ( Test). The results were as shown in Tables 1 to 4, respectively.

[0051]

[Table 3]

[0052]

[Table 4]

The method and evaluation of each test are as follows. Preparation of test pieces First, each aqueous pressure-sensitive adhesive composition was applied to a polyester film (2
5μ) using a Meyer bar on the surface, the dry film is 25 ±
The composition was applied so as to be 1 g / m ² and dried at 100 ° C. for 5 minutes to prepare a test piece.

(Ball tack) The above test piece (5 × 10
cm) was evaluated at an inclination angle of 30 ° according to JIS-Z0237. (Adhesion at room temperature) The above test piece (2.5 × 10 cm) was adhered to a stainless steel plate (SUS) or a polyethylene plate whose surface was polished, and reciprocated once with a 2 kg roller, and then subjected to a tensile test manufactured by Instron. The adhesive strength was evaluated at 20 ° C. using a machine. (Low-temperature adhesive strength) The above test piece (2.5 × 10 cm) was adhered to a stainless steel plate (SUS) or a polyethylene plate whose surface was polished, and reciprocated once with a 2 kg roller, and then subjected to a tensile test manufactured by Instron. The adhesive strength was evaluated at 5 ° C. using a machine. (Holding force) The above test piece (20 × 20 mm) was adhered to a stainless steel plate (SUS) whose surface was polished, and reciprocated once with a 2 kg roller. After 30 minutes, a load of 1 kg was applied, and a temperature of 40 ° C. and a humidity of 65 were applied. %, The holding power (time until peeling) was evaluated.

(Tg: glass transition point) Tg is 1 / Tg =
Shall be calculated by the formula _{W 1 / Tg 1 + W 2} / Tg 2 ··· + W n / Tg n. Where Tg, Tg ₁ , Tg _2.
· · Tg _n denotes the absolute _{temperature, W 1, W 2 ··· W} n denotes a polymerization fraction of the monomer component of the polymer. The following values were used for the Tg of the polymer of the angular monomer. Tg value Poly 2-ethylhexyl acrylate -85C Polybutyl acrylate -54C Polymethyl methacrylate 105C Polyvinyl acetate 30C Polyacrylonitrile 96C Polyacrylic acid 106C Polymethacrylic acid 144C Polydiacetone acrylamide 65C Polyacrolein About 60 ° C

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshihide Orimi 1000 Kawajiri-cho, Yokkaichi, Mie Prefecture Inside Mitsubishi Yuka Birdishe Co., Ltd. In-house (72) Inventor Takao Hattori 1000 Kawajiri-cho, Yokkaichi-shi, Mie, Mitsubishi Yuka Birdishe Co., Ltd.

Claims (2)

(57) [Claims] 1. A core layer comprising at least one tackifier resin selected from the group consisting of (A) a rosin resin having allyl hydrogen, a terpene resin having allyl hydrogen, and a petroleum resin having allyl hydrogen. ) 0.1 to 5% by weight of a carbonyl group-containing unsaturated monomer; (b) 60 to 99.8% by weight of an alkyl ester of acrylic acid having 4 to 12 carbon atoms; (B) an aqueous dispersion of resin particles having a shell layer of a resin obtained by emulsion polymerization of a monomer mixture comprising 0.1 to 39.9% by weight of another copolymerizable unsaturated monomer; An aqueous adhesive composition comprising a hydrazine derivative having at least two hydrazino groups in a molecule, wherein a glass transition temperature of a shell layer of the aqueous dispersion is −85 to −30 ° C. Aqueous adhesive composition. 2. The hydrazino group in the component (B) has a ratio of 0.05 to 1 mol of the carbonyl group in the component (A).
The aqueous adhesive composition according to claim 1, wherein the amount is 5 mol.