JP7099152B2 - Adhesive-imparting resin water-based dispersion, water-based adhesive and pressure-sensitive adhesive sheet - Google Patents

Description

The present invention relates to an aqueous dispersion of a tackifier resin, and an aqueous adhesive and an adhesive sheet using the same.

Adhesives are widely used in industrial fields such as packaging, construction, building materials, automobiles, and electronic parts, as well as in general households. The most common laminated structure of the pressure-sensitive adhesive sheet is "base sheet / pressure-sensitive adhesive layer / release sheet" (single-sided pressure-sensitive adhesive sheet) or "release sheet / pressure-sensitive adhesive layer / base material sheet / pressure-sensitive adhesive layer / release sheet". (Double-sided adhesive sheet). At the time of use, the release sheet is peeled off and the adhesive layer is attached to the adherend. Adhesive sheets are used for various purposes and require various adhesive strengths.

In recent years, from the viewpoint of protecting the global environment (suppressing the emission of volatile organic compounds), improving the working environment, and effectively using resources, an aqueous emulsion adhesive (hereinafter referred to as "aqueous adhesive") has been used as an alternative to solvent-based adhesives. The use of (abbreviated as) has been studied. However, the water-based pressure-sensitive adhesive has the disadvantages that the adhesiveness to the base sheet and the adhesive force to the polyolefin-based adherend such as polyethylene and polypropylene are significantly inferior to those of the solvent-type pressure-sensitive adhesive. It has also been required to have sufficient adhesive strength to difficult-to-attach bodies such as adherends.

Further, in automobile applications and building material applications, there are concerns about sick car problems and sick house problems, so water-based adhesives are widely used. In the case of automobile applications, for example, in the case of interior materials, the temperature inside the vehicle becomes extremely high in the summer, while in the case of building materials, the temperature reaches high temperatures in an environment exposed to direct sunlight in the summer. The agent is required to have heat resistance, moisture heat resistance, and heat retention holding power under such high temperature.

In addition, the base sheet has been diversified recently, and in particular, in automobile applications, the sheet-like foam having irregularities on the surface such as urethane foam is porous, so that the actual contact area with the adhesive layer is small. Therefore, it was difficult to secure the adhesiveness of the pressure-sensitive adhesive layer to the sheet-like foam. The sheet-shaped foam is thicker than a general base sheet such as a plastic film or paper, and has a large force to return to a flat state against bending, that is, a restoring force. However, the adhesive sheet using the sheet-shaped foam as the base sheet is often attached to the adherend having an uneven surface or a curved surface as described above. Therefore, if the adhesive layer has insufficient adhesion to the sheet-shaped foam, the sheet-shaped foam cannot be attached to the adherend against the restoring force of the sheet-shaped foam. That is, peeling occurs between the sheet-shaped foam and the pressure-sensitive adhesive layer, and the sheet-shaped foam is peeled off from the adherend while the pressure-sensitive adhesive layer is left on the adherend.

On the other hand, even if the adhesive layer has sufficient adhesiveness to the sheet-like foam, if the adhesive force of the adhesive layer to the adherend is insufficient, the adhesive layer is between the adherend and the adhesive layer. Peeling occurs, and the sheet-like foam becomes one with the adhesive layer and peels off from the adherend.

As the water-based pressure-sensitive adhesive, in order to improve heat resistance and adhesive strength, acrylic polymer resin dispersion, styrene-butadiene copolymer latex, natural rubber latex, chloroprene latex, etc. are used as base polymers, and rosin-based resin, etc. It is known that it is used as an aqueous pressure-sensitive adhesive obtained by mixing an aqueous dispersion of a pressure-sensitive adhesive resin such as a petroleum-based resin, a terpene-based resin, a phenol resin, a ketone resin, and a polyolefin-based resin. Usually, an aqueous dispersion of a rosin-based resin, a terpene-based resin, and a petroleum-based resin is widely used as the tackifier resin aqueous dispersion because of its good compatibility with the base polymer and good adhesive characteristics. ing.

Various measures have been taken to improve these problems, for example, a specific oxyalkylene group-containing monomer (a) and an ethylenically unsaturated monomer (b) having an anionic group or an anion-forming group. ) And an acrylic copolymer that requires a copolymerizable hydrophobic monomer (c) as a polymer emulsifier, and contains a resin aqueous dispersion of a rosin substance and the resin aqueous dispersion as an active ingredient. A water-based sizing agent for papermaking is disclosed (see Patent Document 1). If this polymer emulsifier is used, a uniform resin aqueous dispersion of rosin substance can be obtained, but when mixed with an approximately resin aqueous dispersion aqueous acrylic resin and used as an aqueous pressure-sensitive adhesive, storage stability over a long period of time In addition, when an adhesive sheet is made, it can have low-temperature adhesiveness due to its high flexibility, but it is not only significantly inferior in heat resistance and moisture heat resistance, but also has poor adhesive strength to polyolefin-based adherends. It was enough.

For example, a polymer having a non-volatile content concentration excluding the surfactant component of 65 to 99% by mass of the tackifier resin (A) and a glass transition temperature (Tg) other than the tackifier resin (A) of -80 ° C to 0 ° C. B) Consisting of 1 to 35% by mass (however, the total of the tackifier resin (A) and the polymer (B) is 100% by mass), and the organic solvent contained in the aqueous dispersion of the tackifier resin (A). An aqueous dispersion of a tackifier resin having an amount of 50 ppm or less is disclosed (see Patent Document 2). Since no organic solvent is used in the production of the tackifier resin aqueous dispersion, there is an advantage that the tackifier resin aqueous dispersion does not contain any solvent. However, the tackifier resin aqueous dispersion is mixed with the acrylic resin. The pressure-sensitive adhesive sheet prepared from the generally water-based pressure-sensitive adhesive has a drawback that the heat resistance and the heat-retaining holding power are extremely lowered because the glass transition temperature (Tg) is low.

For example, the concentration of the non-volatile content excluding the emulsifier component is 135 to 180 ° C., the polymerized rosin-based ester resin (A) having an acid value of 20 or less is 65 to 99% by mass, and the acid value other than (A) is 50 to 100. Acrylic oligomer (B) having a carboxyl group having a mass average molecular weight of 1000 to 5000 is composed of 1 to 35% by mass [the total of the components (A) and (B) is 100% by mass], and is contained in the aqueous dispersion. A tackifier-imparting resin aqueous dispersion in which the amount of the organic solvent contained is 50 ppm or less is disclosed (see Patent Document 3). The aqueous dispersion of the adhesive-imparting resin is applied so as not to contain an organic solvent as much as possible, so that it is effective for environmental protection. However, the aqueous dispersion of the polymerized rosin-based ester resin is mixed with the acrylic resin to be aqueous. A pressure-sensitive adhesive sheet made from a generally water-based pressure-sensitive adhesive as a pressure-sensitive adhesive has insufficient adhesive strength to a polyolefin-based adherend, and when an attempt is made to produce a resin-based water-based dispersion that does not contain a solvent, the water-based dispersion becomes a pressure-sensitive adhesive. There were cases where there were problems such as high viscosity and difficulty in handling.

For example, a tackifier resin having a softening point of 120 to 190 ° C. dispersed in water under pressure-free conditions in the presence of an acrylic oligomer having a mass average molecular weight of 500 to 50,000. Aqueous dispersions are disclosed (see Patent Document 4). Since the aqueous dispersion of the adhesive-imparting resin does not contain an organic solvent, it is effective for environmental conservation, but since it uses a low molecular weight acrylic oligomer, it has an odor due to the residual unreacted acrylic monomer. It is easy to remain, and when the aqueous dispersion of the resin that imparts general adhesiveness is mixed with an acrylic resin to form an aqueous adhesive, the storage stability deteriorates over a long period of time, and when an adhesive sheet is prepared, the temperature is low. Although it can have both adhesiveness and heat resistance, it is not only significantly inferior in water resistance and moisture heat resistance, but also has insufficient adhesive strength to a polyolefin-based adherend.

In this way, when mixed with a base polymer to form an aqueous pressure-sensitive adhesive, it provides excellent adhesive strength, heat resistance, moisture heat resistance, and cohesive power as compared with conventional pressure-sensitive adhesives, and uses an organic solvent. However, an aqueous dispersion of a tackifier resin having good storage stability has been desired.

Japanese Unexamined Patent Publication No. 8-52340 Japanese Unexamined Patent Publication No. 2007-002212 Japanese Unexamined Patent Publication No. 2008-195888 Japanese Unexamined Patent Publication No. 2005-330436

From the viewpoint of contributing to environmental protection and occupational hygiene, the present invention has an extremely low content of organic solvent, and has excellent storage stability, mechanical stability, coatability, processability, adhesiveness, curved surface adhesiveness, and moisture and heat resistance. It is an object of the present invention to provide an aqueous pressure-sensitive adhesive dispersion that imparts constant load peelability and adhesiveness to a substrate, and to provide an aqueous pressure-sensitive adhesive containing the aqueous dispersion of a general adhesive-imparting resin and a pressure-sensitive adhesive sheet using the same. And.

As a result of diligent studies to solve the above problems, the present inventors have found that the above object can be achieved by the tackifier resin aqueous dispersion shown below, and have completed the present invention.

That is, an embodiment of the present invention includes a tackifier resin (A) having a softening point of 100 to 180 ° C., and a copolymer resin (B) having an alicyclic structure and an ethylene oxide unit, and the tackifier resin ( A) A tackifier resin aqueous dispersion containing 0.5 to 50 parts by mass of the copolymer resin (B) with respect to 100 parts by mass and having an organic solvent content of 1000 ppm or less.

Further, in the embodiment of the present invention, as the monomer unit constituting the copolymer resin (B), an ethylenically unsaturated compound (b1) unit having an alicyclic structure and an ethylene unsaturated compound having an ethylene oxide unit are provided. 10 to 30 parts by mass of the compound (b1) in 100 parts by mass of the copolymer resin (B), which contains a compound (b2) unit and an ethylenically unsaturated compound (b3) unit containing a carboxyl group. The tackifier resin aqueous dispersion is characterized by containing 55 to 80 parts by mass of the compound (b2) and 5 to 20 parts by mass of the compound (b3).

Further, in an embodiment of the present invention, the copolymer resin (B) is the tackifier resin aqueous dispersion characterized by having a mass average molecular weight of 1,000 to 300,000.

Further, in an embodiment of the present invention, the copolymer resin (B) is the tackifier resin aqueous dispersion characterized in that the glass transition temperature is in the range of −50 to 20 ° C.

Further, an embodiment of the present invention is characterized in that the tackifier resin (A) is one or more resins selected from the group consisting of a rosin-based resin, a terpene-based resin, and a petroleum-based resin. It is a resin aqueous dispersion.

Further, in the embodiment of the present invention, the liquid resin (C) having a mass average molecular weight of 300 to 50,000 (provided that the tackifier resin (A) and the copolymer resin (B) are used. The above-mentioned tack-imparting resin aqueous dispersion, which is characterized by containing).

Further, an embodiment of the present invention is the tackifier resin aqueous dispersion, which further comprises a surfactant (D).

Further, in an embodiment of the present invention, the surfactant (D) is the tackifier resin aqueous dispersion containing at least one of an anionic surfactant and a nonionic surfactant.

Further, an embodiment of the present invention is the tackifier resin aqueous dispersion, which further comprises the basic compound (E).

Further, an embodiment of the present invention is the tackifier resin aqueous dispersion in which the basic compound (E) is a tertiary amine.

Further, an embodiment of the present invention is an aqueous pressure-sensitive adhesive containing the base polymer (P) and the pressure-imparting resin aqueous dispersion.

Further, an embodiment of the present invention is a pressure-sensitive adhesive sheet provided with a pressure-sensitive adhesive layer formed of the above-mentioned water-based pressure-sensitive adhesive on a base material (G).

The present invention has an extremely low content of organic solvent, and has excellent storage stability, mechanical stability, coatability, workability, adhesiveness, curved surface adhesiveness, moisture resistance and heat resistance, constant load peeling property, and substrate adhesion. To provide a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive resin water-based dispersion and a water-based pressure-sensitive adhesive which can provide a good water-based pressure-sensitive adhesive and a pressure-sensitive adhesive layer formed of the water-based pressure-sensitive adhesive, as well as filterability and pot stain resistance. It has become possible to provide an aqueous dispersion of a pressure-sensitive adhesive resin having a high softening point with good mechanical stability and storage stability.

Hereinafter, embodiments of the present invention will be described.
In addition, in this specification,
Adhesive resin (A) having a softening point of 100 to 180 ° C., copolymer resin (B) having an alicyclic structure and an ethylene oxide unit, an ethylenically unsaturated compound (b1) having an alicyclic structure, an ethylene oxide unit. Ethylene unsaturated compound (b2), ethylenically unsaturated compound (b3) containing a carboxyl group, and other ethylenically unsaturated compound (b4), respectively B), compound (b1), compound (b2) and compound (b3), compound (b4) may be abbreviated.

In addition, when it is described as "(meth) acrylic", "(meth) acryloyl", "(meth) acrylic acid", "(meth) acrylate", "(meth) acryloyloxy", and "(meth) allyl". Unless otherwise specified, "acrylic or methacrylic", "acryloyl or methacrylic acid", "acrylic acid or methacrylic acid", "acrylate or methacrylate", "acryloyloxy or methacryloyloxy", and "allyl or methacrylic acid", respectively. ".
Hereinafter, each component constituting the tackifier resin aqueous dispersion will be specifically described.

<Adhesive-imparting resin (A) having a softening point of 100 to 180 ° C.>
Examples of the tackifier resin (A) having a softening point of 100 to 180 ° C. include a rosin-based resin, a terpene-based resin, a phenol-based resin, a ketone-based resin, and a petroleum-based resin.
Specific examples of rosin-based resins include modified rosins obtained by modifying rosins, hydrides obtained by hydrogenating rosins, disproportionated rosins obtained by disproportionating rosins, and rosins. Examples thereof include polymerized rosins obtained by polymerizing these raw materials (collectively referred to as "raw material rosins"), and rosin esters which are esters of these raw material rosins and alcohols. Examples of the modified rosins include unsaturated acid-modified rosins obtained by modifying rosins with unsaturated acids, and phenol-modified rosins obtained by modifying rosins with phenols. As the unsaturated acid used for producing unsaturated acid-modified rosins, for example, (meth) acrylic acid, fumaric acid, maleic acid and the like can be used. As the phenols used for the phenol-modified rosins, for example, phenol, alkylphenol and the like can be used. The modification method is not particularly limited, and a known method may be adopted. Usually, a method of mixing rosins and unsaturated acids or phenols and heating them is adopted.

Specific examples of the terpene-based resin include a terpene-based resin obtained by polymerizing known terpenes such as α-pinene, β-pinene, and dipentene, or a terpene phenol obtained by copolymerizing terpenes and phenols. High molecular weight resins such as resins and terpene phenolic resins can also be used. In addition, these terpene-based resins may be hydrogenated.

As a specific example of the phenol-based resin, a phenol-formaldehyde resin which is a condensate of phenols and formaldehyde can be used. Examples of the phenols include phenol, m-cresol, 3,5-xylenol, p-alkylphenol, resorcin and the like, and these phenols and formaldehyde are subjected to an addition reaction with an alkali catalyst, or a condensation reaction with an acid catalyst. The obtained novolak and the like can be exemplified. Further, a phenol-acetylene resin obtained by a Leppe reaction using phenols and acetylene as a catalyst with zinc naphthenate or cadmium naphthenate as a catalyst can also be exemplified.

Examples of the ketone resin include methyl ethyl ketone, methyl isobutyl ketone, acetophenone, cyclohexanone and / or a condensate of methylcyclohexanone and formaldehyde.

As the petroleum-based resin, carbon obtained from penten, pentadiene, isoprene, cyclopentadiene, dicyclopentadiene, etc., among the decomposition oils excluding olefins having 2 to 4 carbon atoms such as ethylene, propylene, and butadiene in naphtha decomposition. Adipose-based, alicyclic-based, aromatic-based C9-based petroleum resins such as C5-based petroleum resins having a number of 5 or more and C9-based petroleum resins obtained from inden, methyl inden, vinyl toluene, styrene, α-methylstyrene, β-methylstyrene and the like. Examples thereof include a resin obtained by polymerizing the residual olefins of the above. In addition, C5 to C9 copolymer-based petroleum resins obtained from the above-mentioned various monomers, kumaron-based resins composed of polymers of kumaron and inden which are coal tar fractions, and resins such as dammer and copal can be mentioned.

Among these tackifier resins, the tackifier resin used in the present invention has a softening point in the range of 100 to 180 ° C., more preferably in the range of 120 to 170 ° C., and particularly preferably in the range of 140 to 170 ° C. If the softening point is less than 100 ° C., not only the adhesive strength does not improve when it is contained in the pressure-sensitive adhesive, but also the heat-resistant holding power is lowered, which is not preferable. Not only the compatibility with the base polymer of the above is deteriorated, but also the adhesiveness (also referred to as "tack") and the adhesiveness to the curved surface are deteriorated, which is not preferable.
The softening point in the present invention is the temperature at which the substance softens as the temperature rises and begins to deform, and is a value measured by the ring-and-ball method (JIS K5902).
Of these tackifier resins, known ones can be used without particular limitation as long as the softening point is in the range of 100 to 180 ° C., but rosin is used because of the compatibility of the base polymer and the development of good adhesiveness. A resin, a terpene resin, or a petroleum resin is preferable, and among these, a rosin resin is particularly preferable in terms of curved adhesiveness, water resistance, and moisture heat resistance.

<Copolymer resin (B) having an alicyclic structure and an ethylene oxide unit>
The copolymer resin (B) having an alicyclic structure and an ethylene oxide unit has an ethylenically unsaturated compound (b1) unit having an alicyclic structure and an ethylene oxide unit as a monomer constituting the copolymer. A resin containing an ethylenically unsaturated compound (b2) unit and an ethylenically unsaturated compound (b3) unit containing a carboxyl group is preferable, and a resin obtained by polymerizing a mixture of these monomers is preferable.

<< Ethylene unsaturated compound having an alicyclic structure (b1) >>
The compound (a1) is a compound having an alicyclic structure and an ethylenically unsaturated double bond group, and is a compound containing one or more alicyclic residues. The alicyclic structure is a saturated or unsaturated aliphatic hydrocarbon ring, and may have an aliphatic branch.
The main alicyclic structure includes, for example, monocyclic cycloalkanes such as cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclononane, cyclodecane, cycloundecane, and cyclododecane;
For example, monocyclic cycloalkenes such as cyclopropene, cyclobutene, cyclopropene, cyclohexene, cycloheptene, and cyclooctene.
For example, bicyclic alkanes such as spiropentane, spirodecane, bicycloundecane, decahydronaphthalene (decalin), norcanane, norbornane;
For example, bicyclic alkenes such as norbornene, norbornadiene, spiropentadiene;
For example, polycyclic structures such as dicyclopentadiene, adamantane, cubane, basketane, and housane can be mentioned.

The copolymer resin (B) using the ethylenically unsaturated compound (b1) having such an alicyclic structure as a monomer not only makes it possible to improve an appropriate cohesive force, but also makes it water resistant. It is possible to improve the moisture resistance and heat resistance.
Examples of the compound (b1) include cyclopentyl (meth) acrylate, 1-methyl-1-cyclopentyl (meth) acrylate, 1-ethyl-1-cyclopentyl (meth) acrylate, and 1-isopropyl (meth) acrylate. -1-Cyclopentyl, (meth) acrylate cyclohexyl, (meth) acrylate 1-methyl-1-cyclohexyl, (meth) acrylate 1-ethyl-1-cyclohexyl, (meth) acrylate 4- (tert-butyl) Cyclohexyl, (meth) acrylic acid 1,3,5-trimethylcyclohexyl, (meth) acrylic acid 3,3,5-trimethylcyclohexyl, (meth) acrylic acid 1-isopropyl-1-cyclohexyl, (meth) acrylic acid cyclohexylmethyl , (Meta) Acrylic Acid 1,4-Cyclohexanedimethanol, 2- (Meta) Acryloyloxyethyl Hexahydrophthalate (Meta) Acrylic Acid 1-Ethyl-1-Cyclooctyl, (Meta) Acrylic Acid Isobonyl, (Meta) Acrylic Dicyclopentanyl acid, dicyclopentanyloxyethyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, decahydronaphthalene-2-yl (meth) acrylate , (Meta) decahydro-1,4-methanonaphthalene-2-yl acrylate, (meth) decahydro acrylate-1,4: 5,8-dimethanonaphthalen-2-yl, 2-ethyl (meth) acrylate Decahydro-1,4: 5,8-dimethanoaphthalene-2-yl, (meth) acrylate Decahydro-3,8: 4,7-dimethanocyclobuta [b] naphthalene-5-yl, (meth) Dodecahydro-1H-4,9: 5,8-dimethanocyclopenta [b] naphthalene-5-yl, tetradecanohydro-1,4-methanoanthracen-2-yl (meth) acrylate, (meth) ) Tetradecahydro acrylate-1,4: 9,10-dimethanoanthracen-2-yl, tetradecahydro (meth) acrylate-1,4: 5,8,9,10-trimethanoanthracen-2- Il, (meth) acrylic acid (1s, 3r, 5R, 7S) -3-hydroxyadamantan-1-yl, (meth) acrylic acid (1s, 3R, 5R, 7s) -3,5-dihydroxyadamantan-1- Il, (meth) acrylic acid (3s, 5s, 7s) -adamantan-1-yl, (meth) acrylic acid (1s, 3s, 5R, 7S) )-2-Methyladamantan-1-yl, (meth) acrylic acid (1s, 3s, 5R, 7S) -2-ethyladamantan-1-yl, (meth) acrylic acid (1r, 3r, 5r, 7r)- 2-Ethyladamantan-2-yl, (meth) acrylic acid (1r, 3r, 5r, 7r) -2-isopropyladamantan-2-yl, (meth) acrylic acid {(3r, 5r, 7r) -adamantan-1 -Il} methyl, (meth) acrylic acid 1-{(3r, 5r, 7r) -adamantane-1-yl} ethyl and other monofunctional (meth) acrylic acid cyclic esters;

For example, N-cyclohexyl (meth) acrylamide, N, N-diethyl-3-cyclohexyl (meth) acrylamide, (Z) -N, N-dimethyl-3- (cyclohexyl) (meth) acrylamide, N-cyclohexyloxymethyl ( Monofunctional acrylamides such as meth) acrylamide, N-cyclohexyloxyethyl (meth) acrylamide, N-cyclohexyloxypropyl (meth) acrylamide, N-cyclohexyloxysibutyl (meth) acrylamide, and N-cyclohexyloxidedecyl (meth) acrylamide. Kind;

For example, cyclohexyl vinyl ether, cycloxylmethyl vinyl ether, cyclohexyl ethyl vinyl ether, menthyl vinyl ether, 1,2-cyclohexanedimethanol monovinyl ether, 1,3-cyclohexanedimethanol monovinyl ether, 1,4-cyclohexanedimethanol monovinyl ether, 4-vinyl. Monofunctionals such as -1-cyclohexene, isobonyl vinyl ether, 5-vinylbicyclo [2.2.1] hepta-2-ene (also known as 5-vinyl-2-norbornen), 1-adamantyl vinyl ether, 2-adamantyl vinyl ether, etc. Cyclic vinyl ethers;

For example, 5-vinyl-2-norbornene, 5-vinyl-2,3-oxylannorbornane, 2- (2-propenyl) bicyclo [2.2.1] heptane, 5-vinylbicyclo [2.2.1] hepta. -2-ene, 2,5-bis {(meth) allyloxy} norbornane, cyclohexyl (meth) allyl, 1,2-cyclohexanedimethanol mono (meth) allyl ether, 1,3-cyclohexanedimethanol mono (meth) allyl Monofunctional cyclic vinyl compounds and cyclic (meth) allyl compounds such as ether, 1,4-cyclohexanedimethanol mono (meth) allyl ether, 2-ethenylidene adamantan, 1- (meth) allyl adamantan;

For example, di (meth) acrylic acid 1,4-cyclohexanediol, di (meth) acrylic acid 2,5-norbornandiol, di (meth) acrylic acid 1,4-cyclohexanedimethanol, di (meth) acrylic acid 1, 4-Cyclohexenediol, di (meth) acrylate 1,4-cyclohexene dimethanol, di (meth) acrylate dimethyloltricyclodecane, di (meth) acrylate hexahydrophthalic acid, di (meth) acrylate tricyclo Decandyhydroxymethyl, di (meth) acrylate tricyclodecanedihydroxymethyldicaprolactonate, di (meth) acrylate 2-methyl-1,1'-tricyclo [3,3,1,13,7] decane-1 , 3-Diyl, Di (meth) acrylic acid 1,2-adamantandiol, Di (meth) acrylic acid 1,3-adamantandiol, Di (meth) acrylic acid 1,4-adamantandiol, Di (meth) acrylic acid Bifunctional (meth) acrylic acid cyclic diesters such as 1,2-adamantan dimethanol, di (meth) acrylic acid 1,3-adamantan dimethanol, di (meth) acrylic acid hexahydrophthalic acid;

For example, bifunctional cyclic divinyl compounds such as 1,4-cyclohexanedimethanol divinyl ether, 1,4-cyclohexanedimethanol di (meth) allyl ether, 1,3-divinyladamantane, 2,2-divinyladamantane, and divinyl compounds. Examples thereof include (meth) allyl compounds. Only one of these may be used, or a plurality of types may be used in combination.

Since the compound (b1) exhibits hydrophobicity, a non-polar monomer having 1 to 3 ring structures is preferable, and the compound (b1) is used as a monomer unit constituting the copolymer. Therefore, it can be introduced into the copolymer resin (B). Further, it is preferable that the compound (b1) does not have an aromatic ring. Having no aromatic ring makes it possible to introduce the hydrophobic unit into the copolymer resin (B) without impairing the flexibility of the ethylene oxide unit.
A pressure-sensitive adhesive resin aqueous dispersion containing such a copolymer resin (B) is mixed with a base polymer (P) described later and coated with an aqueous pressure-sensitive adhesive, and a prepared pressure-sensitive adhesive sheet is used as a polyolefin plate. Even if it is attached to an adherend having a low polarity such as, it is possible to maintain a high adhesive strength. In addition, even if the adhesive sheet is attached to the adherend and exposed for a long period of time under humidified heat conditions, it exhibits high cohesive force due to molecular orientation in addition to hydrophobicity, so deterioration phenomena such as foaming, floating and peeling occur. Is significantly suppressed.

<< Ethylene unsaturated compound having an ethylene oxide unit (b2) >>
Next, the ethylenically unsaturated compound (b2) having an ethylene oxide unit will be described.
The ethylenically unsaturated compound (b2) having an ethylene oxide unit is a compound having two or more ether bonds of repeating units in the molecule. Here, the ethylene oxide unit contained in the compound (b2) is a repeating unit (also referred to as the number of added moles) of ethylene oxide (EO, the unit unit of ethylene oxide may be abbreviated as “EO”). Indicates that it has two or more.
By having the ethylene oxide unit in the compound (b2), the tackifying resin (A) can be easily dispersed in water. The number of moles of the ethylene oxide unit (EO) added is preferably 2 to 100, more preferably 4 to 80, and even more preferably 4 to 60. When the number of moles of EO added is in the above range, the copolymer resin (B) has flexibility, so that it is possible to improve the adhesiveness to curved surfaces. It is assumed that the oxygen atom of the ester or ether is also contained in the ethylene oxide unit.

Examples of such compound (b2) include diethylene glycol mono (meth) acrylate, triethylene glycol mono (meth) acrylate, tetraethylene glycol mono (meth) acrylate, and polyoxyethylene polyoxyethylene mono (meth) acrylate. (Number of moles added with EO: 5 to 30), Poly (meth) acrylate (oxyethylene / oxypropylene) (Number of moles with EO: 2 to 30), Poly (meth) acrylate (oxyethylene / oxytetramethylene) ) (Number of moles added with EO: 2 to 30), poly (meth) acrylic acid (oxyethylene / oxybutylene) (number of moles added with EO: 2 to 30), etc. Ethylene oxide-added (meth) acrylic with repeated addition of ethylene oxide. Hydrolipid (meth) acrylic acid esters containing hydroxyl groups such as acid esters;

For example, an ethylene oxide addition system having a hydroxyl group at the end of repeated addition of ethylene oxide such as diethylene glycol monovinyl ether, triethylene glycol monovinyl ether, tetraethylene glycol monovinyl ether, and polyoxyethylene monovinyl ether (EO addition mole number: 5 to 30). Hydrolipid vinyl ethers containing hydroxyl groups such as vinyl ether;

For example, diethylene glycol mono (meth) allyl ether, triethylene glycol mono (meth) allyl ether, tetraethylene glycol mono (meth) allyl ether, polyoxyethylene mono (meth) allyl ether (number of moles added with EO: 5 to 30), etc. A hydroxyl group-containing aliphatic (meth) allyl ether such as an ethylene oxide addition system (meth) allyl ether having a hydroxyl group at the terminal to which the ethylene oxide is repeatedly added;

For example, (meth) methoxydiethylene glycol acrylate, (meth) methoxytriethylene glycol acrylate, (meth) methoxypolyoxyethylene acrylate (number of moles added with EO: 4-40), (meth) methoxypolyoxyethylene acrylate. Polyoxypropylene (number of moles added with EO: 2 to 30, number of moles added with PO: 1 to 20), (meth) ethoxydiethylene glycol acrylate, ethoxytriethylene glycol (meth) acrylate, ethoxypolyoxyethylene (meth) acrylate (Number of moles added with EO: 4 to 40), ethoxypolyoxyethylene / polyoxypropylene (meth) acrylic acid (number of moles added with EO: 2 to 30, number of moles added with PO: 1 to 20), (meth) butoxy acrylate Diethylene glycol, butoxytriethylene glycol (meth) acrylate, butoxypolyoxyethylene (meth) acrylate (number of moles added with EO: 4-40), hexyloxypolyoxyethylene (meth) acrylate (number of moles added with EO: 2 ~) 40), 2-ethylhexyloxypolyoxyethylene (meth) acrylate (number of moles added with EO: 2-40), octyloxypolyoxyethylene (meth) acrylate (number of moles added with EO: 2-40), (meth) Decyloxypolyoxyethylene acrylate (number of moles added with EO: 2-40), (meth) lauryloxypolyoxyethylene acrylate (number of moles added with EO: 4-40), (meth) octyloxypolyoxyethylene polyacrylate (Meta) acrylic acid esters containing an ethylene oxide unit having an alkoxy group such as oxypropylene (number of moles added with EO: 2 to 40);

For example, diethylene glycol methyl vinyl ether, diethylene glycol ethyl vinyl ether, diethylene glycol butyl vinyl ether, triethylene glycol methyl vinyl ether, triethylene glycol ethyl vinyl ether, triethylene glycol butyl vinyl ether, polyoxyethylene methyl vinyl ether (number of moles added by EO: 4 to 30), polyoxy. Vinyl ethers containing an ethylene oxide unit having an alkoxy group such as ethylene ethyl vinyl ether (number of moles added with EO: 4 to 30) and polyoxyethylene butyl vinyl ether (number of moles added with EO: 4 to 30);

For example, diethylene glycol methyl (meth) allyl ether, diethylene glycol ethyl (meth) allyl ether, diethylene glycol butyl (meth) allyl ether, triethylene glycol methyl (meth) allyl ether, triethylene glycol ethyl (meth) allyl ether, triethylene glycol butyl. (Meta) allyl ether, polyoxyethylene methyl (meth) allyl ether (number of moles added with EO: 4 to 30), polyoxyethylene ethyl (meth) allyl ether (number of moles added with EO: 4 to 30), polyoxyethylene butyl (Meta) allyl ethers containing ethylene oxide units having an alkoxy group such as (meth) allyl ethers (number of moles added with EO: 4 to 30);

For example, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyoxyethylene di (meth) acrylate (number of moles added with EO: 5-40), Polyoxyethylene-added trimethylol propantri (meth) acrylic acid ester (EO-added moles: 3 to 30), polyoxyethylene-added pentaerythritol tetra (meth) acrylic acid ester (EO-added moles: 3 to 30), di Polyethylene oxide unit-containing (meth) acrylic acid isocyanuric acid ethylene oxide modification (EO addition mole number: 2 to 30), tri (meth) acrylic acid isocyanuric acid ethylene oxide modification (EO addition mole number: 2 to 30), etc. Functional (meth) acrylic acid esters;

For example, diethylene glycol divinyl ether, triethylene glycol divinyl ether, tetraethylene glycol divinyl ether, polyethylene glycol divinyl ether (EO addition mole number: 5 to 30), polyoxyethylene hydrogenated trimethylol propanetrivinyl ether (EO addition mole number: 3 to 30). 30), Polyoxyethylene-added pentaerythritol Tetravinyl ethers (EO-added moles: 3 to 30) and other ethylene oxide unit-containing polyfunctional vinyl ethers;

For example, diethylene glycol di (meth) allyl ether, triethylene glycol di (meth) allyl ether, tetraethylene glycol di (meth) allyl ether, polyethylene glycol di (meth) allyl ether (EO addition mole number: 5 to 30), poly. Ethylene oxide units such as oxyethylene-added trimethylol propantri (meth) allyl ether (EO-added moles: 3 to 30) and polyoxyethylene-added pentaerythritol tetra (meth) allyl ether (EO-added moles: 3 to 30). Examples thereof include polyfunctional (meth) allyl ethers contained therein, but the present invention is not particularly limited thereto. These may be used alone or in combination of two or more.

The compound (b2) preferably does not have an aromatic ring from the viewpoint of improving the adhesion to the substrate and maintaining the adhesiveness to the curved surface. Further, since the copolymer resin (B) is easily emulsified with water, the tackifier resin (A) can be easily dispersed in water, and separation is suppressed even if it is left over time. Further, it becomes possible to further maintain water resistance and moisture heat resistance.
Further, the tackifier resin aqueous dispersion containing the copolymer resin (B) also has improved compatibility with the base polymer (P) described later, and the aqueous pressure-sensitive adhesive containing the general tackifier resin aqueous dispersion is available. It is possible to appropriately control various physical properties such as good adhesive strength, various resistances, and flexibility.

<< Ethylene unsaturated compound containing a carboxyl group (b3) >>
Subsequently, the ethylenically unsaturated compound (b3) containing a carboxyl group will be described.
The ethylenically unsaturated compound (b3) containing a carboxyl group is a compound having a carboxyl group or an acid anhydride group thereof ((-C = O) -O- (C = O)-) in the molecule. .. By having the copolymer resin (B) having a carboxyl group or an acid anhydride group thereof by the compound (b3), the tackifier resin (A) can be easily dispersed in water. In addition, the aqueous pressure-sensitive adhesive containing the aqueous dispersion of the resin that imparts general adhesion can maintain good adhesive strength and heat-resistant holding power.
Examples of such compound (b3) include (meth) acrylic acid, (meth) acrylic acid 2-carboxyethyl, (meth) acrylic acid 2-carboxypropyl, (meth) acrylic acid 3-carboxypropyl, and (meth) acrylic acid. ) Acrylic acid 4-carboxybutyl, (meth) acrylic acid dimer, maleic acid, fumaric acid, monomethylmaleic acid, monomethylfumalic acid, acconitic acid, sorbic acid, sucrose, α-chlorosorbic acid, glutaconic acid, citraconic acid , Mesaconic acid, itaconic acid, tigric acid, angelic acid, senesioic acid, crotonic acid, isocrotonic acid, mucobromic acid, mucochloric acid, muconic acid, aconitic acid, penicic acid, geranoic acid, citronellic acid, 4-acrylamide butanoic acid, 6 -Polylactone-based (meth) having a carboxyl group at the end due to the addition of a ring-opened lactone ring, such as acrylamide hexane acid, 2- (meth) acryloyloxyethyl succinate, mono (meth) acrylic acid ω-carboxypolycaprolactone ester. A carboxyl group-containing aliphatic acid such as an ester of (meth) acrylic acid and an alkylene oxide-added succinic acid having a carboxyl group at the terminal to which an alkylene oxide such as an acrylic acid ester, ethylene oxide or propylene oxide is repeatedly added. Examples thereof include carboxylic acids containing α, β-unsaturated double-bonding groups and their acid anhydrides, and these may be used alone or in combination of two or more, as described below. From the viewpoint of compatibility with the base polymer (P) shown in (1) and maintenance of curved surface adhesiveness, it is preferable not to have an aromatic ring.

<< Other Ethylene Unsaturated Compounds (b4) >>
Subsequently, the other ethylenically unsaturated compound (b4) will be described.
The other ethylenically unsaturated compound (b4) is an ethylenically unsaturated compound other than the above-mentioned compound (b1), compound (b2) and compound (b3).
The compound (b1), the compound (b2) or the compound which is a monomer unit constituting the copolymer resin (B) by using the compound (b4) as a part of the constituent monomer as needed. It may be easy to improve the efficiency of the copolymerization reaction with (b3). Further, the copolymer resin (B) can be made to have a low viscosity, and the tackability of the tackifier resin (A) at the time of emulsification may be easily improved.
Further, the mass average molecular weight (hereinafter, may be abbreviated as "Mw"), acid value (hereinafter, may be abbreviated as "AV") or viscosity (hereinafter, "Vis") of the copolymer resin (B). (Sometimes abbreviated as) can be controlled, so that the tackifier resin (A) can be easily dispersed in water. Further, the tackifier resin aqueous dispersion containing the copolymer resin (B) also has improved compatibility with the base polymer (P) described later, and the aqueous pressure-sensitive adhesive containing the general tackifier resin aqueous dispersion is available. It is possible to appropriately control various physical properties such as good adhesive strength, various resistances, and flexibility.

Examples of such compound (b4) include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and dodecyl (meth) acrylate, (meth). Cetyl acrylate, stearyl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, (meth) ) 1-butenyl acrylate, 1,3-methyl-3-butenyl (meth) acrylate, (meth) acrylate (methoxycarbonyl) methyl, glycidyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, ( (Meta) Acrylic acid esters such as sulfophenoxyethyl acrylate, (meth) perfluoromethyl acrylate, 3- (meth) acryloyloxypropylmethyldimethoxysilane;

Vinyl esters such as vinyl acetate and vinyl propionate; N-substituted vinyl compounds such as N-vinylpyridine, N-vinylcarbazole, N-vinyl-2-pyrrolidone and N-vinylphthalimide; (meth) acrylamide, dimethyl (meth) ) Acrylamides such as acrylamide and diacetone acrylamide; α-olefins such as 1-butene, 4-methyl-1-pentene, 1-octene, 1-decene and 1-dodecene; (meth) acrylonitrile, styrene and the like. , These may be used alone or in combination of two or more, but the compatibility with the base polymer (P) shown below, the adhesion to the substrate and the maintenance of the adhesiveness to the curved surface are maintained. From the viewpoint, it is preferable not to have an aromatic ring.

<< Copolymer resin (B) >>
The copolymer resin (B) is a copolymer resin having an alicyclic structure and an ethylene oxide unit, and is, for example, the above-mentioned compound (b1) and compound (b2), and if necessary, the compound (b3) and the compound (b). It can be obtained by copolymerizing b4). Among the above-mentioned monomers, a compound having a (meth) acryloyl group is preferable from the viewpoint of reactivity. In various ethylenically unsaturated compounds, the viscosity and emulsifying property of the copolymer resin (B) are controlled, the particle size and storage stability of the tackifying resin aqueous dispersion, and the adhesiveness and durability of the pressure-sensitive adhesive sheet are thus controlled. Alternatively, the above-mentioned compound (b1), compound (b2), compound (b3) and, if necessary, the compound (b4) can be selected as appropriate based on the coating suitability and the like.

The copolymer resin (B) usually contains 0.001 to 20 parts by mass of the polymerization initiator with respect to 100 parts by mass of the total of the monomer mixture of various ethylenically unsaturated compounds as described above according to a conventional method. It is synthesized by a method such as bulk polymerization, solution polymerization, emulsion polymerization, or suspension polymerization. The polymerization method and reaction operation are not particularly limited, but bulk polymerization and high-pressure polymerization are preferable. In the case of bulk polymerization, since no solvent is used, a high polymerization reaction rate can be expected, and it is possible to avoid mixing of excessive additives that have a great influence on physical properties. Further, in the case of high-pressure polymerization, although a pressure kettle is required, a high polymerization reaction rate can be achieved even with a reaction solution having a significantly high viscosity. Further, in the bulk polymerization method, the molecular weight and the viscosity can be controlled by the reaction temperature or the amount of the polymerization initiator, and in the high pressure polymerization method, the reaction temperature, the degree of pressurization and the like. In the polymerization reaction, the basic compound (E) described later can also be used in combination.

Examples of polymerization initiators include 2,2'-azobisisobutyronitrile, 2,2'-azobis (2-methylbutyronitrile), 1,1'-azobis (cyclohexane1-carbonitrile), and 2, , 2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (2,4-dimethyl-4-methoxyvaleronitrile), dimethyl 2,2'-azobis (2-methylpropionate) , Dimethyl 2,2'-azobisisobutyrate, 1,1'-azobis (1-acetoxy-1-phenylethane), 4,4'-azobis (4-cyanovaleric acid), 2,2'- Examples thereof include azobis (2-hydroxymethylpropionitrile), 2,2'-azobis [2- (2-imidazolin-2-yl) propane] and other azo compounds.

In addition, benzoyl peroxide, tert-butyl perbenzoate, cumene hydroperoxide, diisopropyl peroxy dicarbonate, di-n-propyl peroxy dicarbonate, di (2-ethoxyethyl) peroxy dicarbonate, and tert-butyl peroxy. Organics such as -2-ethylhexanoate, tert-butylperoxyneodecanoate, tert-butylperoxyviverate, (3,5,5-trimethylhexanoyl) peroxide, dipropionyl peroxide, and diacetyl peroxide. Examples include peroxide.

Further, at the time of synthesis, mercaptans such as lauryl mercaptan and n-dodecyl mercaptan, and chain transfer agents such as α-methylstyrene dimer and limonene may be used.

Among these, from the viewpoint of molecular weight control and molecular weight distribution control, the polymerization initiators include 2,2'-azobisisobutyronitrile, dimethyl 2,2'-azobis (2-methylpropionate), and dimethyl 2,. 2'-azobisisobutyrate, 2,2'-azobis (2,4-dimethylvaleronitrile), dibenzoyldioxydan, tert-butylperbenzoate, tert-butylperoxypivalate, tert-hexylperoxypi Valate, octanoyl peroxide, lauroyl peroxide and tert-butylperoxy-2-ethylhexanoate are preferred.

The polymerization conditions for the polymerization reaction of the copolymer resin (B) may be appropriately set according to the polymerization method, and are not particularly limited. The polymerization temperature is preferably 20 to 150 ° C, more preferably 40 to 120 ° C. The reaction time may be appropriately set so that the polymerization reaction of each component of the ethylenically unsaturated compound is completed.

The alicyclic structure contained in the copolymer resin (B) is preferably introduced from the compound (b1) and contains 2 to 25% by mass of the alicyclic structure in 100% by mass of the copolymer resin (B). It is more preferably contained in an amount of 5 to 20% by mass. The ethylene oxide unit contained in the copolymer resin (B) is preferably introduced from the compound (b2) and contained in an amount of 40 to 80% by mass in 100% by mass of the copolymer resin (B), preferably 50. It is more preferably contained in an amount of about 70% by mass. When the alicyclic structure and the content of the ethylene oxide unit are in the above range, it is possible to have an effective surface-active ability in which a non-polar moiety having a hydrophobicity is present in the polar moiety being hydrophilic. Therefore, not only can the tackifier resin (A) be easily made water-based, but also the pressure-sensitive adhesive formed by coating with an aqueous pressure-sensitive adhesive using the tackifier resin aqueous dispersion containing the copolymer resin (B) of the present invention. It is also possible to maintain the moisture resistance and heat resistance of the sheet and improve the adhesiveness.

Since the copolymer resin (B) has the above-mentioned alicyclic structure and the ethylene oxide unit, as a monomer unit constituting the copolymer resin (B), in 100 parts by mass of the copolymer resin (B). ,
It is preferable to contain 10 to 30 parts by mass of the compound (b1), 55 to 80 parts by mass of the compound (b2), and 5 to 20 parts by mass of the compound (b3).
It is more preferably within the range of 15 to 30 parts by mass of the compound (b1), 55 to 80 parts by mass of the compound (b2), and 5 to 15 parts by mass of the compound (b3).
The mass ratio of the compound (b1) to the compound (b2) is preferably in the range of 5:95 to 40:60, more preferably in the range of 15:85 to 35:65.
When the content of each monomer is within the above range, the acid value (AV), mass average molecular weight (Mw), and glass transition temperature (hereinafter, abbreviated as "Tg") of the copolymer resin (B) are abbreviated. It is possible to appropriately control various physical properties such as adhesive strength, various resistances, flexibility, compatibility and emulsification.

The copolymer resin (B) has a glass transition point (Tg) of the copolymer resin of −50 to 20 ° C., more preferably −45 to 10 ° C. so as to exhibit good emulsifying property. In addition, it is preferable to select the composition ratio of each monomer which is a constituent component of the copolymer resin. When the Tg is within the above range, not only the emulsification of the tackifier resin (A) becomes easy, but also the flexibility of the pressure-sensitive adhesive sheet obtained from the water-based pressure-sensitive adhesive containing the tackifier-imparting resin aqueous dispersion is maintained. As it is, it is possible to maintain processability such as punching and cutting.

Here, in the copolymer resin (B), the glass transition temperature (Tg) of the copolymer is determined by using a differential scanning calorimeter (DSC) described later, and is a constituent component of each copolymer resin. If the Tg of the homopolymer that can be formed from each ethylenically unsaturated compound is known, the coweight is based on the glass transition temperature (Tg) of each homopolymer and the composition ratio of the ethylenically unsaturated compound. The Tg of the combined resin (B) can be theoretically obtained, and the Tg of the copolymer resin (B) can also be theoretically calculated by the following FOX equation.
<FOX formula> 1 / Tg = W1 / Tg1 + W2 / Tg2 + ... + Wi / Tgi + ... + Wn / Tgn
[In the above FOX formula, the glass transition temperature of the homopolymer of each compound constituting the polymer composed of n kinds of α, β-unsaturated double bond group-containing compounds is Tgi (K), and the mass fraction of each compound is used. The rate is Wi, and it is (W1 + W2 + ... + Wi + ... Wn = 1). ]

Further, as the Tg of the homopolymer, the value described in the literature can be used. As such documents, for example, the following documents can be referred to: Mitsubishi Rayon Acrylic Ester Catalog (2001 version); Osaka Organic Chemical Industry Co., Ltd. Catalog (2009 version); Hitachi Kasei Kogyo Co., Ltd. Funkrill Catalog (2009 version). 2007 edition); and "POLYMER HANDBOOK" 3rd edition, pp. 209-277, published by John Wiley & Sons, Inc. 1989. The Tg of the copolymer resin (B) in the present application was determined by using a differential scanning calorimeter (DSC) described later. Details of the method for measuring the glass transition temperature (Tg) are described in Examples.

The mass average molecular weight (Mw) of the copolymer resin (B) is preferably in the range of 1,000 to 300,000, more preferably in the range of 2,000 to 100,000, 2. The range of 000 to 50,000 is most preferable. The acid value (AV) of the copolymer resin (B) is preferably in the range of 10 to 300, more preferably in the range of 40 to 200, and even more preferably 50 to 100 mgKOH / g. The acid value (AV) is a value measured according to JIS K0070: 1992.
When the mass average molecular weight (Mw) and the acid value (AV) are in the above ranges, the viscosity of the tackifying resin aqueous dispersion can be made low and the emulsifying property is also good. It becomes easy to control in the range of 0.01 to 10 μm. Details of the method for measuring the acid value (AV) and the mass average molecular weight (Mw) are described in Examples.

The tackifier resin aqueous dispersion of the present invention contains 0.5 to 50 parts by mass of the copolymer resin (B) and 1 to 30 parts by mass with respect to 100 parts by mass of the tackifier resin (A). Is preferable. When the copolymer resin (B) is within this range, the viscosity of the tackifier resin aqueous dispersion is lowered, the workability is remarkably improved, and a stable aqueous dispersion can be obtained. Stability is improved. Further, even when it is contained in a base polymer described later to form an aqueous pressure-sensitive adhesive, a stable water-based pressure-sensitive adhesive can be obtained without separation, thickening or de-thickening after standing over time. The pressure-sensitive adhesive sheet obtained after coating and drying the water-based pressure-sensitive adhesive exhibits good adhesiveness, and can improve curved surface adhesiveness and heat-resistant holding power.

<Liquid resin (C) having a number average molecular weight of 300 to 50,000>
Next, the liquid resin (C) having a number average molecular weight of 300 to 50,000 will be described.
In one embodiment of the tackifier resin aqueous dispersion of the present invention, the tackifier resin aqueous dispersion has a number average molecular weight (hereinafter, may be abbreviated as “Mn”) of 300 to 300 in addition to the above essential components. It may contain a liquid resin (C) which is 50,000 (hereinafter, referred to as a liquid resin (C)). The liquid resin is a liquid or paste-like resin at 25 ° C. However, the tackifier resin (A) and the copolymer resin (B) are not included.
The number average molecular weight (Mn) of the liquid resin (C) is 300 to 50,000, preferably 500 to 10,000. When the number average molecular weight (Mn) is in this range, the adsorptivity to the tackifier resin (A) is enhanced, so that the dispersibility is improved and the heat-resistant holding power can be maintained.
Further, the liquid resin (C) is preferably contained in an amount of 0.1 to 50 parts by mass, more preferably 1 to 30 parts by mass, based on 100 parts by mass of the copolymer (A). When the liquid resin (C) is in this range, the dispersibility of the tackifier resin (A) is improved, and not only the particle size can be controlled accurately, but also the tackifier resin aqueous dispersion and the tackiness It is possible to achieve both the storage stability of the aqueous pressure-sensitive adhesive containing the aqueous dispersion of the imparting resin and the water resistance and moisture heat resistance of the pressure-sensitive adhesive layer formed from the water-based pressure-sensitive adhesive.

Specific examples of such a liquid resin (C) include olefin polymers, cyclic olefins, polyols, liquid rosin esters, and the like, but from the viewpoint of compatibility, unsaturated hydrocarbons having 4 to 5 carbon atoms in particular. A polymer of an olefin obtained by polymerizing the above, a cyclic olefin, or a liquid rosin ester is preferable. Examples of unsaturated hydrocarbons having 4 to 5 carbon atoms include 1-butene, isobutene, 2-butene, butadiene, 1-pentene, 2-pentene, isopenten, and isoprene. The polymerization may be carried out by a known method, and radical polymerization, cationic polymerization and the like can be adopted.
As the liquid resin (C), a commercially available product can also be used, and examples of the olefin polymer include NISSO-PB B-1000 (Mn = 1,200) and NISSO-PB G-1000 (Mn = 1,400, Hydroxyl value: 68-78 mgKOH / g), NISSO-PB BI-2000 (Mn = 2,200), NISSO-PB GI-2000 (Mn = 1,500, hydroxyl value = 60-75 mgKOH / g) [above, Japan Made by Soda];
LBR-302 (Mn = 5,500), LBR-361 (Mn = 5,500), L-SBR-820 (Mn = 8,500) [above, manufactured by Kuraray];
Nisseki Polybutene LV-7 (Mn = 300), Nisseki Polybutene LV-50 (Mn = 430), Nisseki Polybutene LV-100 (Mn = 500), Nisseki Polybutene HV-15 (Mn = 630), Nisseki Polybutene HV-35 (Mn = 750), Nisseki Polybutene HV-50 (Mn = 800) [above, manufactured by JXTG Energy Co., Ltd.];
NOF Polybutene 0N (Mn = 370), NOF Polybutene 015N (Mn = 580), NOF Polybutene 3N (Mn = 720), NOF Polybutene 10N (Mn = 1,000) [all manufactured by NOF Corporation];
Examples thereof include RT2730 (Mn = 1,000) and RT2304 (Mn = 800) [all manufactured by HUNSTMAN].

Examples of the liquid rosin ester include super ester L (Mn = 650, liquid rosin ester), super ester A-18 (Mn = 700, liquid rosin ester), and KE-364C (Mn = 221, liquid modified rosin ester) [ Above, liquid rosin manufactured by Arakawa Chemical Industry Co., Ltd.];
Examples thereof include Vanbeam UV-22C (Mn = 3,800, rosin-modified epoxy acrylate) and Vanbeam UV-500 (Mn = 4,200, rosin-modified epoxy acrylate) [above, liquid rosin manufactured by Harima Chemicals, Inc.].

Examples of the cyclic olefin include PRIPOL2033 (Mn = 540, dimerdiol) and PRIPOL1006 (Mn = 600, dimer acid) [above, CRODA Coatings & Polymers].

Examples of the polyol include polyether polyols, polyester polyols, polycarbonate polyols, copolymers thereof, and other glycols.

<Surfactant (D)>
Next, the surfactant (D) will be described.
In one embodiment of the tackifier resin aqueous dispersion of the present invention, the tackifier resin aqueous dispersion may further contain a surfactant (D) in addition to the above essential components.
When the tackifier resin (A) is made into an aqueous dispersion, it is possible to contain the surfactant (D) in terms of emulsion stability.
The surfactant (D) is not particularly limited, and various known surfactants of anionic, nonionic, cationic and amphoteric can be used, but anionic surfactants or nonionic surfactants may be used alone or. It is preferable to contain it in combination. The content thereof is 1 to 20 parts by mass, preferably 1 to 10 parts by mass with respect to 100 parts by mass of the tackifier resin (A). When the surfactant (D) is contained in the above range, it is possible to secure the storage stability of the aqueous dispersion without impairing the water resistance and moisture heat resistance of the adhesive layer.

Examples of the anionic surfactant include organic sulfonic acid, alkali metal salts of sulfate esters, ammonium salts and the like, and specific examples thereof include alkylaryl sulfonates, alkyl (or alkenyl) sulfate ester salts, and polyoxyethylene. Examples thereof include alkyl (or alkenyl) ether sulfate ester salts, polyoxyethylene alkylaryl ether sulfate ester salts, alkyl sulfosuccinic acid ester salts, alkyldiaryl ether disulfonic acids, and derivatives thereof.

Examples of the nonionic surfactant include ether-type or ether ester-type nonionic surfactants such as alkyl or aryl polyoxyethylene ether, polyoxyethylene fatty acid monoester, polyoxyethylene glycerin fatty acid ester, and poly. Ester-type nonionic surfactants such as oxyethylene fatty acid trimethylolpropane, polyoxyethylene fatty acid pentaerythritol, polyoxyethylene sorbitol fatty acid ester, fatty acid monoglyceride, fatty acid diglyceride, fatty acid triglyceride, fatty acid trimylol propane, fatty acid pentaerythritol, and sorbitan fatty acid ester. Examples thereof include a nitrogen-containing nonionic surfactant such as an activator, polyoxyethylene alkylamine, alkylalkanolamide, lauric acid diethanolamide, polyoxyethylene alkylamine monostearate, and polyoxyethylene stearate amide. These can be used alone or in combination of two or more.

<Basic compound (E)>
Next, the basic compound (E) will be described.
In one embodiment of the tackifier resin aqueous dispersion of the present invention, the tackifier resin aqueous dispersion may further contain a basic compound (E) in addition to the above essential components.
The carboxyl group in the tackifier resin (A) or the copolymer resin (B) is partially or wholly neutralized by the basic compound (E), and fine particles are generated by the electric repulsive force between the generated carboxyl anions. Aggregation between them is prevented and stability is imparted to the aqueous dispersion.

The basic compound (E) may be used when synthesizing the copolymer resin (B), or the tackifier resin (A) or the copolymer resin (B) is previously neutralized and then tackled. An aqueous dispersion of the imparting resin may be prepared, may be blended when the tackifier resin (A) and the copolymer resin (B) are mixed, or both may be used in combination.
The basic compound (E) is not particularly limited, and examples thereof include inorganic salts, ammonia, and organic bases. Among the organic bases, an organic amine compound having a boiling point of 300 ° C. or lower is preferable from the viewpoint of water resistance and moisture heat resistance of the coating film. When the boiling point is 300 ° C. or lower, it can be easily removed from the resin coating film by drying, and the water resistance / moisture heat resistance of the coating film, adhesion to the substrate, and adhesiveness are improved. As described above, the basic compound (E) may be used during the polymerization reaction to obtain the copolymer resin (B).

Specific examples of the organic amine compound include triethylamine, tributylamine, N, N-dimethylethanolamine, aminoethanol, N-methyl-N, N-diethanolamine, N, N-dimethylbenzylamine, isopropylamine, and iminobispropylamine. , Ethylamine, diethylamine, 3-ethoxypropylamine, 3-diethylaminopropylamine, sec-butylamine, dibutylamine, propylamine, methylaminopropylamine, 3-methoxypropylamine, monoethanolamine, morpholine, N-methylmorpholine, N -Ethylmorpholin, diazabicycloundecene and the like can be mentioned.

Among these organic amine compounds, tertiary amine (e1), which has good scattering property, is hard to remain in the coating film, and is non-reactive with the copolymer resin (B), is particularly preferable and industrially available. Particularly preferred are triethylamine, tributylamine, N, N-dimethylethanolamine, N, N-dimethylbenzylamine, N-methylmorpholine, N-ethylmorpholine, diazabicycloundecene and the like. The basic compound other than the tertiary amine (e1) is referred to as a basic substance (e2).

The content of the basic compound (E) may be 0.5 to 20.0 times the total amount of carboxyl groups contained in the tackifier resin (A) and the copolymer resin (B). Preferably, 1.0 to 10.0 times equivalent is more preferable. When the content of the basic compound (E) is in the above range, the drying time at the time of forming the coating film is short, and the stability of the aqueous dispersion can be improved.

<Other compounds (F)>
Next, the other compound (F) will be described.
In one embodiment of the tackifier resin aqueous dispersion of the present invention, the tackifier resin aqueous dispersion may further contain other compound (F) in addition to the above essential components as long as the problem can be solved.
The other compound (F) includes the tackifier resin (A), the copolymer resin (B), the liquid resin (C), the surfactant (D), the surfactant (D), the basic compound (E), and the like. It is a compound other than the base polymer (P), and is a compound having a function of improving the stability and physical properties of the material by adding a small amount of components. For example, hardeners, thickeners, plasticizers, preservatives, rust inhibitors, freeze-melt stabilizers, pigments, colorants, fillers, wetting agents, antioxidants, flame retardants, storage stabilizers, UV absorption. Examples thereof include agents, thixotropy-imparting agents, dispersion stabilizers, fluidity-imparting agents, film-forming aids, moisturizing agents, pH adjusters, leveling agents, hydrolysis inhibitors and defoaming agents.
The other compound (F) can be further added and used in the aqueous pressure-sensitive adhesive described later.

<Adhesive-imparting resin aqueous dispersion>
Next, the tackifier resin aqueous dispersion will be described.
As described above, the tackifier resin aqueous dispersion of the present invention comprises the copolymer resin (B) and, if necessary, the liquid resin (C), the surfactant (D), the basic compound (E) and other compounds. It is obtained by emulsifying the tackifier resin (A) while coexisting with (F).
Further, the tackifier resin aqueous dispersion preferably does not contain an organic solvent, and even if it is contained due to the residual organic solvent derived from the raw material, the content is preferably 1,000 ppm or less, more preferably 500 ppm or less. It is preferably 100 ppm or less, and most preferably 100 ppm or less.
The emulsification method is not particularly limited, and any of known emulsification methods such as high-pressure emulsification method, reversal emulsification method, ultrasonic emulsification method, and solvent emulsification method may be adopted, but the simplicity of equipment and production cost may be adopted. When environmental problems are taken into consideration, it is preferable to adopt a solvent-free inverted emulsification method that does not use an organic solvent. In the case of the solvent-free reverse emulsification method, the tackifier resin (A) is melted at the softening point or higher by using various emulsifiers such as various mixers, colloid mills, high-pressure emulsifiers, and high-pressure discharge emulsifiers. Under pressure or pressure, the copolymer resin (B) and, if necessary, the liquid resin (C), the surfactant (D), the basic compound (E) and the other compound (F) are premixed. An aqueous dispersion can be obtained by adding water and inverting the phase.

The non-volatile content concentration of the tackifier resin aqueous dispersion thus obtained is not particularly limited, but is usually adjusted appropriately so as to be about 20 to 70% before use. The average particle size of the obtained tackifier resin aqueous dispersion is usually about 0.1 to 2 μm, and most of the particles are uniformly dispersed as particles of 1 μm or less. The aqueous dispersion has a white to milky white appearance, has a pH value of about 5 to 11, and has a viscosity of usually about 10 to 2,000 mPa · s.

<Aqueous adhesive>
The aqueous pressure-sensitive adhesive of the present invention contains the base polymer (P) and the pressure-imparting resin aqueous dispersion.

<< Base Polymer (P) >>
The base polymer (P) used in the present invention exhibits tack (adhesiveness) at a glass transition temperature (Tg) of −70 to 0 ° C. and 25 ° C., and is mainly used as a main component of an aqueous pressure-sensitive adhesive. It is a dispersion. The base polymer (P) is preferably at least one selected from the group consisting of an acrylic aqueous dispersion, a rubber aqueous dispersion and a synthetic resin aqueous dispersion. As the base polymer, one type may be used alone, or two or more types may be used in combination.
As the acrylic aqueous dispersion, those generally used for various acrylic pressure-sensitive adhesives and the like can be used. For example, an aqueous dispersion produced by polymerizing a (meth) acrylic acid ester may be used. Can be done.
Further, as the rubber-based aqueous dispersion, various known substances used for the aqueous pressure-sensitive adhesive can be used. For example, natural rubber latex, styrene-butadiene copolymer latex, chloroprene latex and the like can be mentioned.
Further, the synthetic resin-based aqueous dispersion is a synthetic resin-based emulsion excluding the acrylic-based aqueous dispersion, and various known ones used for an aqueous pressure-sensitive adhesive can be used. Examples thereof include synthetic resin-based aqueous dispersions such as vinyl acetate-based aqueous dispersions, ethylene-vinyl acetate copolymer aqueous dispersions, and urethane-based aqueous dispersions.

The acrylic aqueous dispersion is synthesized according to a conventional method using 0.001 to 20 parts by mass of a polymerization initiator with respect to 100 parts by mass in total of the monomer mixture. For example, 2,2'-azobis (2-methylpropionamidine) dihydrochloride, azo-based such as 2,2'-azobis (2-amidinopropane) dihydrochloride, persulfate such as potassium persulfate and ammonium persulfate, Peroxides such as benzoyl peroxide, t-butyl hydroperoxide and hydrogen peroxide can be used. Further, a redox initiator composed of a combination of a persulfate and sodium bisulfite, a combination of a peroxide and sodium ascorbate, or the like can also be used. Usually, these polymerization initiators may be added in a predetermined amount at each stage of emulsion polymerization so that the polymerization reaction can be carried out.

The water-based pressure-sensitive adhesive of the present invention is not particularly limited in the combined use ratio of the base polymer (P) and the tack-imparting resin aqueous dispersion, but the effect of modification by the tack-imparting resin aqueous dispersion can be sufficiently exhibited, and As an appropriate range of use that does not cause deterioration of heat retention and tack due to excessive use, a pressure-imparting resin aqueous dispersion is usually 1 to 100 mass by mass with respect to 100 parts by mass (nonvolatile content equivalent) of the base polymer (P). It is preferable to include a part (converted to non-volatile content).

It is preferable that the viscosity of the aqueous pressure-sensitive adhesive of the present invention is appropriately adjusted according to the mode of use thereof. The aqueous pressure-sensitive adhesive of the present invention may additionally use water to adjust the viscosity, if necessary. The viscosity can also be reduced by heating the aqueous pressure-sensitive adhesive without the use of additional moisture.

When the pressure-sensitive adhesive layer is formed using the aqueous pressure-sensitive adhesive of the present invention, the film thickness of the pressure-sensitive adhesive layer is preferably 0.5 to 100 μm, more preferably 1 to 50 μm. When the film thickness is in the above range, it is possible to obtain a sufficient adhesive force.
Therefore, from the viewpoint of coating film formation, the viscosity of the aqueous pressure-sensitive adhesive is preferably in the range of 500 to 15,000 mPa · s as measured by a B-type viscometer at 25 ° C., preferably 1,000. More preferably, it is in the range of about 10,000 mPa · s. When the viscosity is 15,000 mPa · s or less, a thin film of 0.5 to 100 μm can be easily formed on the substrate by coating, and it is also easy to enhance the adhesive physical properties such as tack, adhesive strength and holding power. Is. On the other hand, when the viscosity is 500 mPa · s or more, it is easy to control the film thickness of the pressure-sensitive adhesive layer formed from the water-based pressure-sensitive adhesive. In the present embodiment, the film thickness, viscosity, or non-volatile content concentration of the pressure-sensitive adhesive layer is set according to the use of the laminated body.

The viscous pressure-sensitive adhesive of the present invention may further contain the above-mentioned other compound (F) in addition to the above-mentioned essential components as long as the problem can be solved.

<Adhesive sheet>
Next, the adhesive sheet will be described.
The pressure-sensitive adhesive sheet (also referred to as an adhesive film) of the present application is a sheet-like base material (also referred to as a release liner) whose surface has been peeled off, in which a pressure-sensitive adhesive layer made of the above-mentioned water-based pressure-sensitive adhesive is formed on a base material described later. ) May be laminated.
When producing a pressure-sensitive adhesive sheet, a water-based pressure-sensitive adhesive is applied to a base material described later by an appropriate method according to a conventional method, and then water is removed by a method such as heating to form a pressure-sensitive adhesive layer on the base material. Can be formed. For example, a method of applying a water-based adhesive to the peeled surface of the peeling liner, drying it, and laminating a base material to be used can be mentioned.

The method of applying the water-based adhesive is not particularly limited. For example, various well-known methods such as Meyer bar, applicator, brush, spray, roller, gravure coater, die coater, kiss coater, lip coater, comma coater, blade coater, knife coater, reverse coater, spin coater, dip coater, etc. Can be applied. Further, the form of thin film coating or thick film coating can also be selected without particular limitation depending on the intended use.

The basic laminated structure of the pressure-sensitive adhesive sheet is a single-sided pressure-sensitive adhesive sheet such as a base material / pressure-sensitive adhesive layer / release liner, or a double-sided pressure-sensitive adhesive sheet such as a release liner / pressure-sensitive adhesive layer / base material / pressure-sensitive adhesive layer / release liner. .. The laminated body laminated on the release liner in this way is called an adhesive sheet. At the time of use, the release liner is peeled off and the adhesive layer is attached to the adherend. When a water-based adhesive is applied, not only does the adhesive layer have adhesiveness at the moment when the adhesive layer touches the adherend, but also an adhesive other than the adhesive (hereinafter, simply referred to as an adhesive) is used. Unlike, it is necessary to have a cohesive force for maintaining a sticking state while having a tack and an appropriate hardness without completely solidifying during sticking. The cohesive force largely depends on the molecular weight and the crosslink density. A laminate laminated in the structure of the base material / adhesive layer / adherend in this way is referred to as a bonded laminate.

The pressure-sensitive adhesive sheet using the water-based pressure-sensitive adhesive of the present invention is used for a wide range of applications of various known pressure-sensitive adhesive products (labels, seals, tapes, stickers, etc.), and the water-based pressure-sensitive adhesive is based on two or more base materials (bases). One of the materials forms a base material for the pressure-sensitive adhesive sheet, and the other side of the base material forms a pressure-sensitive adhesive layer to which a base material (referred to as an adherend) is attached. The water-based adhesive of the present invention is generally used for building materials used for adhering materials such as concrete, cement mortar, various metals, leather, glass, vinyl chloride sheet, decorative paper, plywood panel, gypsum board, and ceiling. It is used for automobile interior materials such as materials, decorative parts, door rims, seats, instrument panels, dash silencers, center consoles, pillar trims, and rear parcels, and wire covering materials such as binding tapes for wires. Of these, it is particularly preferable that it is used for a poorly adherent base material.

As the difficult-to-adhere base material, a foam base material having holes such as a polyolefin foam, a soft polyether type, a soft polyester type, a hard polyether type, a hard polyester type polyurethane foam, and a vinyl chloride foam;
Polyethylene, polypropylene, poly-1-butene, polyisobutylene, ethylene-propylene copolymer, propylene-1-butene copolymer or block polymer, ethylene-propylene-diene ternary copolymer, polymethylpentene, cyclo An olefin resin base material such as a copolymer of pentadiene and ethylene and / or propylene;
Plastic resin base materials such as PET (polybutylene terephthalate resin), PBT (polybutylene terephthalate resin), PVC (vinyl chloride resin), nylon, PC (polycarbonate resin), polyallylate resin, PPS (polyphenylene sulfide resin), etc. are listed. Be done. The tackifier resin aqueous dispersion contained in the aqueous pressure-sensitive adhesive of the present invention exhibits excellent adhesion to a poorly adhesive substrate.

As described above, examples of the peeling liner include those obtained by peeling the surface of a sheet-like substrate such as cellophane, various plastic sheets, paper, and metal foil. Further, as the sheet-like base material, a single-layer material may be used, or a material in a multi-layered state in which a plurality of base materials are laminated can also be used.

Hereinafter, specific examples of the present invention will be described together with comparative examples, but the present invention is not limited to the following examples. Further, in the following Examples and Comparative Examples, "parts" and "%" represent "parts by mass" and "% by mass", respectively, unless otherwise specified.

<Synthesis of copolymer resin (B)>
(Synthesis Example 1)
The following monomers, polymerization initiators and basic compounds are added to the polymerization tank and dropping device of the polymerization reaction device equipped with a polymerization tank, stirrer, thermometer, reflux condenser, dropping device, and nitrogen introduction tube in the following ratios, respectively. I prepared it.

[Polymerization tank]
1-Methyl-1-cyclopentyl acrylate (b1) 5.22 parts Methacrylic acid (b3) 2.91 parts Triethylamine (e1) 6.59 parts V65 (polymerization initiator) 0.24 parts
[Dripping device]
1-Methyl-1-cyclopentyl acrylate (b1) 12.18 parts Methoxypolyoxyethylene acrylate (b2) 72.8 parts Methacrylic acid (b3) 6.79 parts Triethylamine (e1) 15.37 parts V-65 (polymerization) Initiator) 0.56 copies

After replacing the air in the polymerization tank with nitrogen gas, the mixture was heated to 80 ° C. with stirring under a nitrogen atmosphere to start the polymerization. The mixture containing the ethylenically unsaturated compound, the basic compound (E) and the polymerization initiator was added dropwise from the dropping device under the reflux temperature over 2 hours. After completion of the dropping, 0.1 part of the polymerization initiator was added twice every 1 hour with stirring, and then the reaction was continued for 3 hours. Then, 11.38 parts of triethylamine (e1) was added and cooled to 25 ° C. to obtain an amine solution of the copolymer resin (B). This solution is yellow transparent, has a non-volatile content concentration (NV) of 75.3%, a solution viscosity (Vis) of 750 mPa · s (25 ° C.), and the copolymer resin (B) has a glass transition temperature (Tg)-. The acid value (AV) of the copolymer was 63.5 mgKOH / g, and the mass average molecular weight (Mw) was 18,000 at 41 ° C.

<Synthesis Examples 2-27>
Synthesized by reacting in the same manner as in Synthesis Example 1 except that the types and blending amounts of the monomers constituting the copolymer resin, the polymerization initiator, and the basic compound (E) were changed according to Table 1. The copolymer resins of Examples 2 to 25 were synthesized.
The compound (b1) and the compound (b3) shown in Table 1 represent the total value (part) of the amount charged into the polymerization tank and the amount charged into the dropping tank.
Of these, the copolymer resins obtained in Synthesis Examples 1 to 11 and 15 to 25 are the copolymer resin (B), and the copolymer resins obtained in Synthesis Examples 12 to 14, 26 and 27 have the same weight. It is a copolymer resin (for comparative examples) that is not a coalesced resin (B).
The solution appearance, non-volatile content concentration (NV), solution viscosity (Vis), acid value (AV), mass average molecular weight (Mw) and glass transition temperature (Tg) of the obtained copolymer resin were determined according to the method described below. The results are shown in Table 1. The numerical values shown in Table 1 are total amounts (parts) including the amount charged into the polymerization tank and the amount charged into the dropping device, unless otherwise specified, and blanks indicate that they are not used.

<Manufacturing of adhesive resin aqueous dispersion>
(Manufacturing Example 1)
The following tackifier resin (A), copolymer resin (B), etc. Ion-exchanged water and, if necessary, a surfactant (D), a surfactant (D), and a basic compound (E) were charged in the following ratios.

[Stirring tank]
D-160 (A) 100 parts Copolymer resin (B) obtained in Synthesis Example 1 10 parts
[Dripping device 1]
10 parts of N, N-dimethylbenzylamine (e1)
[Dripping device 2]
80 copies of ion-exchanged water

After replacing the air in the stirring tank with nitrogen gas, the temperature was raised to 180 ° C. in a nitrogen stream while stirring, and the mixture was heated and melted for 1 hour. Then, the reaction temperature was cooled to 120 ° C., and then N, N-dimethylbenzylamine (e1) was added dropwise from the dropping device 1 in 0.5 hour. Further, the inside of the reaction system was vigorously stirred while being maintained at 100 ° C., ion-exchanged water was added dropwise from the dropping device 2 over 2 hours, and the phase was changed to obtain an aqueous dispersion. Further, 16.7 parts of ion-exchanged water was added and cooled to 25 ° C., and the mixture was filtered through a 180 mesh furnace cloth to obtain a tackifier resin aqueous dispersion having a non-volatile content concentration of 50.1%. At this time, the productivity, filterability, pot stainability, storage stability and mechanical stability were evaluated according to the methods described below, and the results are shown in Table 2.
Further, the non-volatile content concentration (NV), solution viscosity (Vis), average particle size (Dm) and hydrogen ion index (pH) of the obtained tackifier resin aqueous dispersion were obtained according to the method described below, and the results are shown in Table 2. It was shown to.

(Manufacturing Examples 2-75)
Production Examples 2 to 70 are the same as in Production Example 1 except that the types and blending amounts of the tackifier resin (A), the copolymer resin (B) and other materials are changed according to Table 2 as needed. Aqueous dispersion of adhesive-imparting resin was produced. The liquid resin (C) was charged into the stirring tank, the basic compound (E) was charged into the dropping device 1, and the ion-exchanged water and, if necessary, the surfactant (D) were charged into the dropping device 2.
Further, in Production Examples 73 to 75, the liquid resin (C) (Production Examples 73, 74) and the surfactant (D) (Production Example 75) were used without using the copolymer resin (B).
Further, the other compound (F) was added and mixed after cooling to 25 ° C. The numerical values shown in Table 2 represent "parts" unless otherwise specified, and blanks indicate that they are not used.
Among these, the aqueous dispersions obtained in Production Examples 1-9, 14-23, 25-33, 37-43, 47-50, 53-67, 69 and 70 are the tackifier resin aqueous dispersions of the present invention. The aqueous dispersions obtained in Production Examples 10 to 13, 24, 34 to 36, 44 to 46, 51, 52, 68 and 71 to 75 are not the tackifier resin aqueous dispersions of the present invention. Is. The non-volatile content concentration (NV), solution viscosity (Vis), average particle size (Dm), hydrogen ion index (pH) and organic solvent content of the obtained aqueous dispersion were determined according to the method described below, and the results are shown in Table 2. It was shown to. The ion-exchanged water shown in Table 2 represents the total value (part) of the amount charged into the dropping device 2 and the amount for adjusting the non-volatile content concentration. Further, in Production Examples 34, 36 and 52, in addition to the above, a part of the ion-exchanged water charged in the stirring tank was changed to toluene as an organic solvent. Further, Production Examples 46 and 73 could not be made water-based.

<Synthesis of base polymer (P)>
(Synthesis Example 101)
The following ethylenically unsaturated monomers, chain transfer agents, surfactants and ion-exchanged water were charged into the stirring tank of a stirring device equipped with a stirring tank, a stirrer and a thermometer in the following ratios.

[Stirring tank]
2-Ethylhexyl acrylate acrylate 81.94 parts Methyl methacrylate 10.18 parts 2-hydroxyethyl methacrylate 3.31 parts Acrylic acid 4.58 parts Octyl thioglycolate (chain transfer agent) 0.02 parts Reactive surface activity Agent 5.0 parts Ion exchanged water 30.5 parts

An aqueous dispersion of the monomer was obtained while stirring the inside of the stirring tank. Next, in the reaction tank and the dropping device of the polymerization reaction device equipped with the polymerization tank, the stirrer, the thermometer, the reflux condenser, the dropping device, and the nitrogen introduction tube, the following monomeric aqueous dispersion and the polymerization initiator are added to the reaction tank and the dropping device, respectively. It was prepared at the ratio of.

[Polymerization tank]
36.17 parts of ion-exchanged water
[Dripping device]
Aqueous dispersion of the above monomer 0.05 part 3% potassium persulfate aqueous solution (polymerization initiator) 10 parts

After replacing the air in the polymerization tank with nitrogen gas, the temperature was raised to 80 ° C. while stirring under a nitrogen atmosphere, and 0.1 part of a 3% potassium persulfate aqueous solution was added as a non-volatile content.
After 5 minutes, the aqueous dispersion of the monomer and the 3% aqueous potassium persulfate solution were added dropwise from the dropping device over 3 hours.
While maintaining the reaction temperature at 80 ° C., while further stirring, add 1.0 part of a 3% potassium persulfate aqueous solution twice every 0.5 hours after completion of the dropping, and then ripen for 2 hours to continue the reaction. did. Then, the mixture was cooled to 25 ° C. and adjusted to pH = 7.5 with aqueous ammonia to obtain a base polymer (acrylic resin aqueous dispersion) having a non-volatile content concentration of 60%. The non-volatile content concentration (NV), solution viscosity (Vis), and average particle size (Dm) of the obtained base polymer were determined according to the method described below, and the results are shown in Table 3.

(Synthesis Examples 102 and 103)
A base polymer (acrylic resin aqueous dispersion) was synthesized in the same manner as in Synthesis Example 101, except that the materials and blending amounts shown in Table 4 were changed. The non-volatile content concentration (NV), solution viscosity (Vis), and average particle size (Dm) of the obtained base polymer were determined according to the method described below, and the results are shown in Table 3.

《Appearance of solution》
The appearance of the copolymer (B) solutions obtained in Synthesis Examples 1 to 25 was visually observed under the conditions of 25 ° C., respectively. It is good if it is not extremely blackish.

<< Non-volatile content concentration (NV) >>
About 1 g of each of the copolymer resin solution or the aqueous dispersion of the base polymer obtained in each synthesis example and the tackifier resin aqueous dispersion obtained in each production example are weighed in a metal container and placed in an oven at 150 ° C. After drying for 20 minutes, the residual amount was weighed and the residual rate was calculated to obtain the non-volatile content concentration (solid content) (unit:%).

<< Solution Viscosity (Vis) >>
The copolymer resin solution obtained in Synthesis Examples 1 to 27, the aqueous dispersion of the base polymer obtained in Synthesis Examples 101 to 103, or the tackifying resin aqueous dispersion obtained in Production Examples 1 to 75, respectively. Measured at 25 ° C. with a B-type viscometer (TV-22 manufactured by Toki Sangyo Co., Ltd.) under the conditions of rotor No. 2 to 4, rotation speed of 0.5 to 100 rpm, and rotation for 1 minute. It was set to mPa · s).

《Average molecular weight》
For the copolymer resins obtained in Synthesis Examples 1 to 27, the number average molecular weight (Mn) and the mass average molecular weight (Mw) were measured by GPC (gel permeation chromatography) manufactured by Showa Denko KK. The number average molecular weight (Mn) and the mass average molecular weight (Mw) were determined by converting polystyrene as a standard substance.
Device name: Showa Denko GPC (Gel Permeation Chromatography) "Shodex GPC System-21"
Column: GMHXL manufactured by Tosoh Co., Ltd .: 4 pieces, HXL-H manufactured by Tosoh Co., Ltd.: 1 line were connected in series.
Mobile phase solvent: Tetrahydrofuran (THF)
Flow rate: 1.0 ml / min Column temperature: 40 ° C

《Acid value (AV)》
For the copolymer resins obtained in Synthesis Examples 1 to 27, weigh accurately about 1 g of a sample in an Erlenmeyer flask with a stopper, and add 100 ml of a toluene / ethanol (volume ratio: toluene / ethanol = 2/1) mixture. Dissolved. Phenolphthalein test solution was added as an indicator, held for 30 seconds, and then titrated with a 0.1N alcoholic potassium hydroxide solution until the solution turned pink.
The acid value was calculated by the following formula. The acid value was taken as the value of the dry state of the resin (unit: mgKOH / g).
Acid value (mgKOH / g) = {(5.611 × a × F) / S} / (nonvolatile content concentration / 100)
However, S: sample collection amount (g)
a: Consumption of 0.1N alcoholic potassium hydroxide solution (ml)
F: Titer of 0.1N alcoholic potassium hydroxide solution

<< Glass transition temperature (Tg) >>
The glass transition temperature (Tg) of the copolymer resin obtained in Synthesis Examples 1 to 27 was measured by the robot DSC (differential scanning calorimeter, "RDC220" manufactured by Seiko Instruments) and "SSC5200 Disk Station" (manufactured by Seiko Instruments). Was connected and measured.
Place about 10 mg of the sample in an aluminum pan, weigh it, set it in a differential scanning calorimeter, hold it at a temperature of 100 ° C for 5 minutes using an aluminum pan of the same type without a sample as a reference, and then use liquid nitrogen. It was rapidly cooled to 120 ° C. Then, the temperature was raised at a heating rate of 10 ° C./min, and the glass transition temperature (Tg, unit: ° C.) was determined from the obtained DSC chart.

<< Average particle size (Dm) >>
The average particle diameters of the aqueous dispersions of the base polymers obtained in Synthesis Examples 101 to 103 and the tackifying resin aqueous dispersions obtained in Production Examples 1 to 75 were measured using "Microtrac" manufactured by Nikkiso Co., Ltd. .. For the average particle size, a value of 50% of the cumulative percentage was applied.

<< Hydrogen ion index (pH) >>
The pH obtained from the aqueous dispersion of the base polymer obtained in Synthesis Examples 101 to 103 or the tackifier resin aqueous dispersion obtained in Production Examples 1 to 75 was F-52S manufactured by HORIBA, electrode: model 6377-10D. Was measured using.

<< Evaluation of filterability >>
The tackifier resin aqueous dispersions obtained in Production Examples 1 to 75 were filtered through a 180 mesh furnace cloth and evaluated in three stages. In the case of "○" or "△" evaluation, there is no problem in actual use.
◯: Can be filtered quickly and has no residue. Good.
Δ: It takes some time for filtration, and some residue remains to the extent that it does not affect the non-volatile content concentration. Can be used practically.
X: Filtration time is long and there is a considerable amount of residue. The non-volatile content concentration is decreasing. Not practical.

《Evaluation of pot stains》
The state of solid matter adhering to the wall of the stirring tank after the production of the tackifying resin aqueous dispersions obtained in Production Examples 1 to 75 and the detergency with water were evaluated in three stages. In the case of "○" or "△" evaluation, there is no problem in actual use.
◯: No adhesion at all and good detergency Δ: There is some adhesion of solid matter, but the detergency is good. Can be used practically.
X: There is a lot of solid matter adhering to it, and it cannot be removed by washing. Not practical.

<< Evaluation of storage stability >>
The tackifying resin aqueous dispersion obtained in Production Examples 1 to 75 was collected in a 225 ml mayonnaise bottle, stored at 25 ° C. for 1 month with a lid, and then the dispersoid and liquid layer of the aqueous dispersion ( The state of separation of the dispersion medium) was evaluated in three stages. In the case of "○" or "△" evaluation, there is no problem in actual use.
◯: The aqueous dispersion does not separate even after storage for 1 month. Good.
Δ: It separates after storage for 2 weeks or more, but returns to a uniform aqueous dispersion by shaking. Can be used practically.
X: Separation after storage for less than 2 weeks or shaking does not return to a uniform aqueous dispersion. Not practical.

<< Evaluation of mechanical stability >>
5 g of water was added to 50 g of the tackifier resin aqueous dispersion obtained in Production Examples 1 to 75 to dilute the mixture, and the mixture was filtered through a 300 mesh wire mesh, and 50 g of the water was used as a test sample. Using a Maron type mechanical stability tester [manufactured by Tester Sangyo Co., Ltd.], a mechanical load is applied for 10 minutes under the conditions of a temperature of 25 ° C., a load of 15 kg, and a rotation speed of 1,000 rpm, and then 300 mesh of agglomerates are formed. The dry mass of the agglomerates was calculated with respect to the dry mass of the initial aqueous dispersion, and the mechanical stability was evaluated in three stages based on the agglomerate formation ratio (%). In the case of "○" or "△" evaluation, there is no problem in actual use.
◯: The agglomerate formation ratio is less than 0.1%. Good.
Δ: The agglomerate formation ratio is in the range of 0.1 to 1.0%. Can be used practically.
X: The agglomerate formation ratio exceeds 1.0%. Not practical.
Here, the agglomerate formation ratio was calculated by the following method.
Aggregate formation rate (%) = 100 x (aggregate mass) / (initial mass of test sample)

<< Evaluation of solvent content >>
The tackifier resin aqueous dispersion obtained in Production Examples 1 to 75 was diluted to 1% by mass with water as needed by using gas chromatography ["Gas Chromatograph GC-8A" manufactured by Shimadzu Corporation]. The product was directly put into the apparatus, the content of the organic solvent was determined, and the evaluation was made in three stages. In the case of "○" or "△" evaluation, there is no problem in actual use. The detection limit is 100 ppm.
Carrier gas: Nitrogen
Column filling material (manufactured by GL Sciences)
: PEG-HT (5%) -Uniport HP (60/80 mesh)
Column size: Diameter 3mm x 3m
Sample injection temperature (injection temperature): 180 ° C
Column temperature: 80 ° C
Internal standard substance: n-butanol]
◯: The content of the organic solvent is less than 100 ppm (below the detection limit). Good.
Δ: The content of the organic solvent is in the range of 100 to 1,000 ppm. Can be used practically.
X: The content of the organic solvent exceeds 1,000 ppm. Not practical.

The abbreviations of the materials used in each synthesis example and each production example are shown below. In addition, the numerical value represents a part, the blank indicates that there is no compounding, and the “-” display indicates that the evaluation has not been performed.

<Table 1>
-Compound (b1)
MCPA: 1-methyl-1-cyclopentyl acrylate, CHMA: cyclohexyl methacrylate, IBXMA: isobonyl methacrylate, DCPMA: dicyclopentanyl methacrylate, VNB: 5-vinyl-2-norbornene compound (b2)
MO9A: methoxypolyoxyethylene acrylate (number of moles with EO added: 9), MO9MA: methoxypolyoxyethylene methacrylate (number of moles with EO added: 9), OEPMA: octyloxypolyoxyethylene polyoxypropylene methacrylate (mol with EO added) Number: 8, number of moles with PO added: 6), EOVE: polyoxyethylene methyl vinyl ether (number of moles with EO: 8), PHEOA: phenoxypolyoxyethylene acrylate (number of moles with EO: 2)
-Compound (b3)
AA: Acrylic acid, EAA: 2-carboxyethyl acrylate, MAA: Methacrylic acid-Compound (b4)
2EHA: 2-ethylhexyl acrylate, LA: lauryl acrylate, BZMA: benzyl methacrylate, AAM: acrylamide ・ Polymerization initiator V65: 2,2'-azobis (2,4-dimethylvaleronitrile) [Wako Pure Chemical Industries, Ltd. Manufactured by "V65"], PBO: tert-butylperoxy-2-ethylhexanoate [manufactured by Nippon Oil & Fats Co., Ltd. "Perbutyl O"]
-Basic compound (E)
TEA: Triethylamine, DBU: Diazabicycloundecene, EA: 2-Aminoethanol

<Table 2>
-Adhesive-imparting resin (A)
D160: Polymerized rosin ester ["Pencel D-160" manufactured by Arakawa Chemical Industry Co., Ltd., softening point = 160 ° C.], KT3: Polymerized rosin ester ["Hariester KT-3" manufactured by Harima Kasei Co., Ltd., softening point = 180 ° C.], KR140: Hydrogen rosin ester ["Pine Crystal KR-140" manufactured by Arakawa Chemical Industry Co., Ltd., softening point = 140 ° C.], FTR: Petroleum resin ["FTR6125" manufactured by Mitsui Chemicals Co., Ltd., softening point = 125 ° C.], T160: Ester / phenolic resin [YShara Chemical's "YS Polystar T160", softening point = 160 ° C]
-Adhesive-imparting resin EH that is not the adhesive-imparting resin (A): Rosin ester ["Ester gum H" manufactured by Arakawa Chemical Industry Co., Ltd., softening point = 68 ° C.]
-Copolymer resin (B)
Synthesis example: Compounds obtained in each synthesis example shown in Table 2 (Synthesis Examples 1-27)
・ Liquid resin (C)
HV100: Polybutene [JXTG Energy Co., Ltd. "Nisseki Polybutene HV-100", Mn = 980], P1025: Dimeric acid [CRODA Co., Ltd. "Pripol1025", Mn = 560.9], P2010: Polyester polyol [Kuraray Co., Ltd. " Kuraray Polyol P-2010 ", Mn = 2,000], UV22C: Rosin-modified epoxy acrylate ["Bangbeam UV-22C "manufactured by Harima Kasei Co., Ltd., Mn = 3,800]
-Surfactant (D) (anion)
LAEOA: Polyoxyethylene lauryl ether ammonium sulfate (number of moles of EO addition: 20), SR20: polyoxyethylene-1- (allyloxymethyl) alkyl ether ammonium glycerin sulfonate (number of moles of EO addition: 20) SR20 "]
-Surfactant (D) (nonion)
STEO: Polyoxyethylene stearyl ether (number of moles of EO added: 50)
-Basic compound (e1)
TEA: triethylamine, DMBA: N, N-dimethylbenzylamine-basic compound (e2)
EA: 2-Aminoethanol ・ Water W: Ion-exchanged water ・ Organic solvent TOR: Toluene ・ Other compounds (F)
KM73A: Silicone defoamer [Shin-Etsu Chemical Co., Ltd. "Shin-Etsu Silicone KM-73A"]

<Table 3>
-Ethylene unsaturated monomer BA: butyl acrylate, 2EHA: 2-ethylhexyl acrylate, MMA: methyl methacrylate, MA: methyl acrylate, HEMA: 2-hydroxyethyl methacrylate, AA: acrylic acid, DAAM: Diacetone Acrylamide ・ Chain transfer agent SGO Octyl thioglycolate ・ Surface active agent KH10: Reactive surfactant [[Daiichi Kogyo Seiyaku Co., Ltd. “Aqualon KH-10”]
-Polymerization initiator KPS: 3% potassium persulfate aqueous solution-Water W: Ion-exchanged water

The mass described in the column of the polymerization initiator in Table 1 is the total mass of the mass added in the polymerization tank three times during the dropping, and the post-addition is the total mass added twice after the completion of the dropping. Means. Further, the mass described in the column of the polymerization initiator in Table 3 means the sum of the mass charged in the dropping tank and the mass added twice after the completion of dropping.

<Aqueous adhesive>
Using the tackifier resin aqueous dispersion obtained in the above production example, an aqueous pressure-sensitive adhesive was prepared by the following methods.
(Example 1)
The following base polymer, tackifier resin aqueous dispersion and other compound (F) {crosslinking agent, viscosity modifier, defoaming agent and preservative} are added to the stirring tank of the stirring device equipped with a stirring tank, a stirrer and a thermometer. It was prepared in the following ratio.

[Stirring tank]
100 parts of base polymer (P) of Synthesis Example 101 10 parts of tackifying resin aqueous dispersion of Production Example 1 5% aqueous solution of adipic acid dihydrazide (crosslinking agent) 1.0 part Adecanol UH-420 (viscosity adjuster) 0.4 Part SN Deformer 154 (antifoaming agent) 0.1 part Deltop 100N (preservative) 0.01 part

A homomixer [“LZB46-HM-3” manufactured by Chuo Rika Co., Ltd.] was used as a stirrer, and the mixture was stirred at a rotation speed of 2,000 rpm for 0.5 hours. Next, while stirring, Acrysol ASE-60 (viscosity adjuster), ammonia water and ion-exchanged water were added to adjust the pH, and the non-volatile content concentration (NV) was about 50% and the solution viscosity (Vis) was about 8,000 mPa · s. , The hydrogen ion index (pH) was adjusted to about 8.2 to obtain an aqueous pressure-sensitive adhesive. The non-volatile content concentration (NV), solution viscosity (Vis) and hydrogen ion index (pH) of the obtained aqueous pressure-sensitive adhesive were determined according to the above method, and the results are shown in Table 4.

(Examples 2 to 70, Comparative Examples 1 to 19)
Among the materials listed in Table 5, the base polymer, the tackifier resin aqueous dispersion, the cross-linking agent, the viscosity modifier, the defoaming agent and the preservative are blended according to the description in Table 4, and the mixture is stirred and mixed to obtain the respective aqueous pressure-sensitive adhesives. Obtained.
Each of the obtained aqueous pressure-sensitive adhesives was applied to each base material, dried and bonded to prepare a pressure-sensitive adhesive sheet, which was evaluated by the following method. The results of each are shown in Table 6. In Comparative Examples 11 and 17, the water-based pressure-sensitive adhesive was not produced or coated because the filterability of the tack-imparting resin aqueous dispersion was extremely poor.

<< Evaluation of storage stability >>
The aqueous pressure-sensitive adhesives obtained in each Example and Comparative Example were collected in a 225 ml mayonnaise bottle in the same manner as above, stored at 25 ° C. for 1 month with a lid, and then the dispersoid and liquid of the water-based pressure-sensitive adhesive. The state of separation of the layer (dispersion medium) was evaluated in three stages. In the case of "○" or "△" evaluation, there is no problem in actual use.
◯: The aqueous dispersion does not separate even after storage for 1 month. Good.
Δ: It separates after storage for 2 weeks or more, but returns to a uniform aqueous dispersion by shaking. Can be used practically.

X: Separation after storage for less than 2 weeks or shaking does not return to a uniform aqueous dispersion. Not practical.

<< Evaluation of mechanical stability >>
50 g of the aqueous pressure-sensitive adhesive obtained in each Example and Comparative Example was collected, diluted with 5 g of water and filtered through a 300-mesh wire mesh, and 50 g of the sample was used as a test sample. Using a Maron type mechanical stability tester [manufactured by Tester Sangyo Co., Ltd.], a mechanical load is applied for 10 minutes under the conditions of a temperature of 25 ° C., a load of 15 kg, and a rotation speed of 1,000 rpm, and then 300 mesh of agglomerates are formed. The dry mass of the agglomerates was calculated with respect to the dry mass of the initial aqueous pressure-sensitive adhesive, and the mechanical stability was evaluated in three stages based on the agglomerate formation ratio (%). In the case of "○" or "△" evaluation, there is no problem in actual use.
◯: The agglomerate formation ratio is less than 0.1%. Good.
Δ: The agglomerate formation ratio is in the range of 0.1 to 1.0%. Can be used practically.
X: The agglomerate formation ratio exceeds 1.0%. Not practical.
Here, the agglomerate formation ratio was calculated by the following method.
Aggregate formation rate (%) = 100 x (aggregate mass) / (initial mass of test sample)

<< Evaluation of coatability >>
The obtained aqueous pressure-sensitive adhesive is coated on commercially available glassine paper (hereinafter, also referred to as "glassine separator") that has been peeled off as a peeling liner so that the thickness of the pressure-sensitive adhesive layer after drying is 18 μm. Then, the pressure-sensitive adhesive layer was formed by drying with hot air at 100 ° C. for 2 minutes. Next, a commercially available high-quality paper having a thickness of 60 μm was bonded to the coated surface to prepare a pressure-sensitive adhesive sheet composed of high-quality paper / adhesive layer / release liner. Then, the state of the pressure-sensitive adhesive layer surface (coated surface) after the peeling liner was peeled off was visually observed and evaluated in three stages. In the case of "○" or "△" evaluation, there is no problem in actual use.
◯: The coated surface is smooth with no repellency, foaming or streaks. Good.
Δ: Some cissing and foaming are observed at the edge of the coated surface. Can be used practically.
X: Repellent, foaming and streaks were observed on the entire coated surface. Bad.

<< Evaluation of workability >>
Each adhesive sheet prepared by the same method as the above-mentioned << Evaluation of coatability >> was cured in an environment of 23 ° C. and a relative humidity of 50% for 3 days. After that, it was cut into a width of 100 mm and a length of 100 mm, 20 sheets were stacked, and the adhesive layer was projected from the end of the adhesive film when pressed at 40 ° C.-60 kg / cm ² for 1 hour as follows. Was evaluated on a three-point scale. In the case of "○" or "△" evaluation, there is no problem in actual use.
◯: No protrusion of the adhesive layer is observed. Good.
Δ: Extrusion of the adhesive layer of less than 0.3 mm is observed, but it can be used practically.
X: Extrusion of the adhesive layer of 0.3 mm or more is observed. Bad.

<< Measurement of peel strength >>
Each adhesive sheet prepared by the same method as the above << Evaluation of coatability >> is cut into a width of 25 mm × a length of 100 mm, the release liner is peeled off, and the exposed adhesive layer is a polyethylene (PE) plate having a thickness of 3 mm. The sample was attached to the sample in an environment of 23 ° C. and a relative humidity of 50%, and a roll having a mass of 2 kg was reciprocated once to obtain a measurement sample. This measurement sample was left to stand in an environment of 23 ° C. and a relative humidity of 50% for 1 day, and then peeled off at a peeling speed of 300 mm / min using a tensile tester (“Tencilon” manufactured by Orientec) under the same environment. The peel strength was measured under the condition of an angle of 180 degrees (peeling strength measurement one day after bonding).
Further, the measurement sample was left to stand in an environment of 60 ° C. and a relative humidity of 95% for 3 days, and then the peel strength was measured by the same method (measurement of peel strength after 3 days of moist heat). This peel strength was evaluated as an adhesive force in three stages. In the case of "○" or "△" evaluation, there is no problem in actual use.
◯: Adhesive strength is 20.0 (mN / 25 mm) or more. Good.
Δ: Adhesive strength is 15.0 (mN / 25 mm) or more and less than 20.0 (mN / 25 mm). Practical is possible.
X: Adhesive strength is less than 15.0 (mN / 25 mm). It is defective and cannot be used practically.

《Measurement of holding power》
Each adhesive sheet prepared by the same method as the above << Evaluation of coatability >> is cut into a width of 25 mm × a length of 100 mm, and the peeling liner is peeled off so that the bonded portion becomes 25 mm × 25 mm, and the exposed adhesive is exposed. The layer was attached to a stainless steel (SUS) plate having a thickness of 3 mm in an environment of 23 ° C. and a relative humidity of 50%, and a roll having a mass of 2 kg was reciprocated once to obtain a measurement sample.
After leaving this measurement sample in an environment of 40 ° C for 20 minutes, a load of 1 kg is applied in an environment of 40 ° C, and a holding force tester [manufactured by Tester Sangyo Co., Ltd.] is used for 70,000 seconds under the condition of 40 ° C. The measurement was performed, and the time until the load dropped, or when the load did not drop, the length deviated from the initial pasting was measured and evaluated in the following three stages. In the case of "○" or "△" evaluation, there is no problem in actual use.
◯: There is no drop of load, and the deviation is less than 0.5 mm. Good.
Δ: There is no drop in load, but the deviation is 0.5 mm or more. Practical is possible.
×: Fall in less than 70,000 seconds. It is defective and cannot be used practically.

<< Evaluation of curved surface adhesiveness >>
Each adhesive sheet prepared by the same method as the above-mentioned << Evaluation of coatability >> is cut into a width of 20 mm and a length of 22 mm, and is formed on a curved surface of a polyethylene (PE) resin cylinder having a diameter of 10 mm. It was affixed along the direction, crimped with a 2 kg rubber roller, and left for 24 hours in an atmosphere of 23 ° C.-50%. Then, the peeling state of the end portion in the length direction of the sample was visually observed and evaluated in three stages according to the following criteria.
◯: No peeling is performed, or the portion of the sample end less than 0.1 mm is peeled. Good Δ: The portion of 0.1 to 0.5 mm at the end of the sample is peeled off. Practical is possible.
X: The portion of the sample end exceeding 0.5 mm is peeled off. It is defective and cannot be used practically.

<< Evaluation of constant load peelability test >>
The obtained aqueous pressure-sensitive adhesive was applied onto the peeled surface of the glassine separator so as to have a thickness of 60 μm after drying, and dried with hot air at 100 ° C. for 2 minutes to form a pressure-sensitive adhesive layer. Next, a polyester non-woven fabric layer of the skin material, which is a sheet-like foam having a three-layer structure consisting of a skin layer (fabric) / urethane foam layer / polyester non-woven fabric layer and having a thickness of 10 mm, is bonded to the original thickness of the skin material. Pressurized and pressure-bonded to 10% of the thickness to prepare a pressure-sensitive adhesive sheet composed of a skin material / pressure-sensitive adhesive layer / release liner.
Each of the obtained adhesive sheets was cut into a width of 25 mm and a length of 100 mm, the release liner was peeled off, and the exposed adhesive layer was formed of a polypropylene plate (hereinafter, also referred to as “PP plate”) at 23 ° C. The sample was attached in an environment of 50% relative humidity, and a roll having a mass of 2 kg was reciprocated once to obtain a measurement sample.
The obtained measurement sample was left to stand in an environment of 23 ° C. and a relative humidity of 50% for 24 hours, and then left to stand in an environment of 80 ° C. for 1 hour. It was kept horizontal, a weight of 100 g was hung from the end of the adhesive sheet in the part not attached, left for 1 hour, and the length of the part peeled off from the PP plate was measured. If all of the PP plate was peeled off within 1 hour, the time until then was measured and evaluated on a 3-point scale according to the following criteria. The test was conducted in an environment of 80 ° C. In the case of "○" or "△" evaluation, there is no problem in actual use.
◯: Does not fall and has a deviation of less than 20 mm. Good and practically no problem.
Δ: Fall in 50 minutes or more. Practical is possible.
×: Dropped in less than 50 minutes. It is defective and cannot be used practically.

<< Evaluation of substrate adhesion >>
Peel off the peeling liner from each pressure-sensitive adhesive sheet prepared by the same method as the above-mentioned << Evaluation of constant load peelability test >> and rub the exposed pressure-sensitive adhesive layer with a finger to see if the pressure-sensitive adhesive layer falls off from the skin material that is the base material. Whether or not it was evaluated on a three-point scale based on the following criteria. In the case of "○" or "△" evaluation, there is no problem in actual use.
◯: Does not fall off from the base material even if rubbed more than 15 round trips. Good and practically no problem.
Δ: It falls off from the base material after 5 to 15 round trips. Practical is possible.
X: The adhesive drops off in less than 5 round trips. It is defective and cannot be used practically.

The materials used in the examples and comparative examples are shown below. In Tables 4 and 5, blanks mean no compounding, and "-" indicates unpainted.
・ Base polymer (P)
Synthesis Examples: Acrylic aqueous dispersions (Synthesis Examples 101 to 103) obtained in each of the synthesis examples shown in Table 4, LA50: chloroprene latex [“LA-50” manufactured by Denka, NV = 50%], GFL280: chloroprene. Latex [Tosoh's "Skyprene Latex GFL-280", NV = 52%]
-Adhesive-imparting resin aqueous dispersion Production example: Adhesive-imparting resin aqueous dispersion obtained in each production example shown in Table 2 (Production Examples 1 to 75).
・ Crosslinking agent (F)
ADH: 5% aqueous solution of adipic acid dihydrazide ・ Viscosity adjuster (F)
UH420: "Adecanol UH-420" manufactured by Adeka Corporation, NV = 30%, ASE60: "Acrysol ASE-60" manufactured by Dow Chemical Corporation, NV = 28%
・ Defoamer (F)
SN154: "SN Deformer 154" manufactured by San Nopco Ltd.
・ Preservative (F)
100N: "Deltop 100N" manufactured by Osaka Gas Chemical Co., Ltd.
・ Water W: Ion-exchanged water

As described above, the water-based adhesive of the present invention has storage stability and mechanical properties in Examples 1 to 23, 25 to 28, 30, 31, 36 to 47, 53, 54, 58 to 61, and 63 to 70. "△" evaluation (practical level) is 3 or less out of 10 items in all of stability, coatability, workability, peel strength, holding power, curved surface adhesiveness, constant load peeling and substrate adhesion. And all the others are evaluated as "○" (good level), so it can be seen that they are excellent.
Further, in Examples 24, 29, 32, 33, 48-52, 55-57 and 62, the “Δ” evaluation (practical level) of each evaluation is 4 to 10 out of 10 items, and “×”. Since there is no evaluation (defective level), it can be used without any problem in practical use.
On the other hand, in Comparative Examples 1 to 19, any one of storage stability, mechanical stability, coatability, workability, peel strength, holding power, curved surface adhesiveness, constant load peeling, and substrate adhesion is obtained. It turns out to be extremely inferior.

The tackifier resin aqueous dispersion according to the present invention has excellent filterability, pot stain resistance, mechanical stability and storage stability even if the tackifier resin is contained in a high concentration without using an organic solvent. Since it is possible to have a tackifier resin aqueous dispersion having a high softening point and the compatibility with the base polymer is also good, the aqueous pressure-sensitive adhesive containing the general tackifier resin aqueous dispersion has excellent storage stability. , Mechanical stability, coatability, workability, adhesiveness, curved surface adhesiveness, moisture and heat resistance, constant load peeling property, substrate adhesion, etc. , Electrical equipment field (for example, home appliances, kitchen equipment, air conditioning, etc.), transport equipment field (for example, ships, automobiles, etc.), furniture field, miscellaneous goods field, etc. be.

Claims (11)

It contains a tackifier resin (A) having a softening point of 100 to 180 ° C., and a copolymer resin (B) having an alicyclic structure and an ethylene oxide unit.
The copolymer resin (B) is contained in an amount of 0.5 to 50 parts by mass with respect to 100 parts by mass of the tackifier resin (A).
As the monomer unit constituting the copolymer resin (B), an ethylenically unsaturated compound (b1) unit having an alicyclic structure, an ethylenically unsaturated compound (b2) unit having an ethylene oxide unit, and a carboxyl group Contains 10 to 30 parts by mass of the compound (b1) and 55 to 80 parts by mass of the compound (b2) in 100 parts by mass of the copolymer resin (B). , And 5 to 20 parts by mass of the compound (b3).
A tackifying resin aqueous dispersion having an organic solvent content of 1000 ppm or less. The tackifier resin aqueous dispersion according to claim 1 , wherein the copolymer resin (B) has a mass average molecular weight of 1,000 to 300,000. The tackifier resin aqueous dispersion according to claim 1 or 2 , wherein the copolymer resin (B) has a glass transition temperature in the range of −50 to 20 ° C. The tackiness according to any one of claims 1 to 3 , wherein the tackifier resin (A) is one or more resins selected from the group consisting of a rosin-based resin, a terpene-based resin, and a petroleum-based resin. Applying resin aqueous dispersion. Further, it is characterized by containing a liquid resin (C) having a mass average molecular weight of 300 to 50,000 (excluding the case where the tackifier resin (A) and the copolymer resin (B) are used). The tackifier resin aqueous dispersion according to any one of claims 1 to 4 . The tackifier resin aqueous dispersion according to any one of claims 1 to 5 , further comprising a surfactant (D). The tackifier resin aqueous dispersion according to claim 6 , wherein the surfactant (D) contains at least one of an anionic surfactant and a nonionic surfactant. The tackifier resin aqueous dispersion according to any one of claims 1 to 7 , further comprising the basic compound (E). The tackifier resin aqueous dispersion according to claim 8 , wherein the basic compound (E) is a tertiary amine. An aqueous pressure-sensitive adhesive comprising the base polymer (P) and the tack-imparting resin aqueous dispersion according to any one of claims 1 to 9 . A pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer formed from the water-based pressure-sensitive adhesive according to claim 10 on the base material (G).