KR100633667B1 - Aqueous dispersion type pressure-sensitive adhesive composition, pressure-sensitive adhesive sheet, and pressure-sensitive adhesive rubber foam sheet using the sheet - Google Patents

Abstract

An object of the present invention is to provide a water-dispersible pressure-sensitive adhesive composition which has excellent adhesion to a foam and terminal peeling performance, and is stable in time of adhesion (adhesion after time). Moreover, an object of this invention is to provide the adhesive sheet provided with the adhesive layer which consists of said water-dispersible adhesive composition on a base material, and the rubber foam adhesive sheet provided with these on one side or both sides of a rubber foam.

A pressure-sensitive adhesive sheet using a water-dispersible pressure-sensitive adhesive composition comprising a (meth) acrylic acid ester as a main component and a tackifier containing a phenol skeleton added to a polymer obtained by copolymerizing a monomer mixture containing a silane monomer and Rubber foam adhesive sheets are provided according to the present invention.

Description

Aqueous dispersion type pressure-sensitive adhesive composition, pressure-sensitive adhesive sheet, and rubber foam pressure-sensitive adhesive sheet using the sheet             

1 is a cross-sectional view schematically showing an example of the pressure sensitive adhesive sheet of the present invention.

2 is a cross-sectional view schematically showing still another example of the pressure-sensitive adhesive sheet of the present invention.

3 is a cross-sectional view schematically showing still another example of the pressure-sensitive adhesive sheet of the present invention.

4 is a cross-sectional view schematically showing still another example of the pressure-sensitive adhesive sheet of the present invention.

5 is a cross-sectional view schematically showing an example of the rubber foam adhesive sheet of the present invention.

6 is a cross-sectional view schematically showing still another example of the rubber foam adhesive sheet of the present invention.

7 is a cross-sectional view schematically showing still another example of the rubber foam adhesive sheet of the present invention.

8 is an explanatory diagram schematically showing a method for measuring the adhesive force to a rubber foam in an embodiment of the present invention.

It is explanatory drawing which showed schematically the measuring method of the terminal peelability test in the Example of this invention.

It is explanatory drawing which showed schematically the measuring method of the adhesive force of the rubber foam adhesive sheet in the Example of this invention.

Explanation of symbols for main parts of the drawings

1: pressure-sensitive adhesive layer 2: base material

3: release liner 4: pressure-sensitive adhesive layer

5: adhesive sheet 6: adhesive sheet

7: back treatment layer 8: foam

The present invention relates to a water-dispersible pressure-sensitive adhesive composition and a pressure-sensitive adhesive sheet (including tape, sheet, film, etc.) provided on the substrate and a rubber foam pressure-sensitive adhesive sheet having these on one or both sides of the rubber foam. .

Conventionally, rubber foams fill gaps in various industrial products, such as construction civil engineering, electrical equipment, housing equipment, and members of ships, vehicles, automobiles, etc., for dustproofing, insulation, soundproofing, dustproofing, cushioning, watertightness, and airtightness. It is widely used as a sealing material for making. In recent years, it is also widely used in the field of information devices such as PCs, mobile phones or PDAs.

The rubber foam is vulcanized and foamed by adding a vulcanizing agent and a foaming agent to a rubber polymer having excellent weather resistance, cold resistance, heat resistance, chemical resistance and the like, such as EPDM (ethylene propylene diene rubber), and an adhesive layer is added to facilitate construction. It is provided with.

Conventionally, the adhesive composition used for this use mainly used the solvent type adhesive composition which melt | dissolved the acryl-type or rubber type polymer in the organic solvent. However, in recent years, a switch to a solvent-free type has been desired in terms of environmental problems and hygiene problems in the working environment.

The pressure-sensitive adhesive sheet using the water-dispersible pressure-sensitive adhesive composition, which is a kind of non-solvent type, is preferable for environmental hygiene because it does not use an organic solvent, and has excellent advantages in terms of solvent resistance. However, such a water-dispersible PSA sheet has a drawback that it is difficult to achieve both adhesiveness and adhesion to adherends (particularly, roughened surfaces such as foams) and inferior practical properties such as terminal peelability compared to solvent-type PSA sheets.

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining in order to solve the said problem, when it polymerizes by adding a silane monomer and a chain transfer agent as needed to the monomer mixture which has a water dispersion type (meth) acrylic-acid alkylester as a main component, it adheres to the adherend and oil-retaining property. Was found to be compatible to a high level, and practical properties (terminal peelability, etc.) equivalent to the solvent-based pressure-sensitive adhesive were obtained (Japanese Patent Laid-Open No. 2001-163655).

However, even when the above-mentioned pressure-sensitive adhesive was used, it was difficult to obtain satisfactory adhesive strength with respect to the rubber foam, and in some cases, the adhesiveness deteriorated with time depending on the type of rubber foam. This deterioration in time-dependent adhesiveness is a phenomenon which can be seen not only in the case where the foam is used as an adherend but also in the foam adhesive sheet based on the foam.

An object of the present invention is to provide a water-dispersible pressure-sensitive adhesive composition that is excellent in adhesion to a foam and terminal peeling performance, and has stable adhesion over time. Moreover, an object of this invention is to provide the adhesive sheet provided on the base material with the adhesive layer which consists of said water-dispersible adhesive composition, and the rubber foam adhesive sheet provided with these on one side or both sides of a rubber foam.

As a result of earnestly examining the above problems, the present inventors found that the decrease in adhesion due to the passage of time is due to the migration of the non-polar components (paraffin oil, asphalt, etc.) of the rubber foam into the pressure-sensitive adhesive layer. By adding a tackifier containing a phenol skeleton to a polymer copolymerized with a silane monomer to a monomer mixture containing meth) acrylic acid ester as a main component, it is possible to prevent the movement of the nonpolar components of the rubber foam, thereby providing excellent adhesion to the rubber foam. It was found that an adhesive having terminal peeling performance and excellent adhesion stability over time was obtained, thereby completing the present invention.

The reason why the excellent effect can be obtained by adding a tackifier containing a phenol skeleton into the pressure-sensitive adhesive composition is not clear, but when the polarity of the pressure-sensitive adhesive is low, the non-polar component of the rubber-based foam is likely to move to the pressure-sensitive adhesive layer, and thus the adhesion strength is improved over time. Although a decrease is caused, it is considered that when the polarity is high, the movement of the component is suppressed and the decrease in adhesion force does not occur. Specifically, in the case where a low-polar polymerization rosin ester is added as a tackifier, the decrease in adhesion is observed, whereas in the case where a high-position rosin phenol or terpene phenol is added, the decrease in adhesion is suppressed. It is guessed that the phenol skeleton in a molecule is working effectively.

That is, the present invention is an aqueous dispersion formed by adding a tackifier containing a phenol skeleton to an aqueous dispersion of a polymer obtained by copolymerizing a monomer mixture containing (meth) acrylic acid alkyl ester as a main component and a silane monomer. As an adhesive composition (claim 1), especially when a polymer superposes | polymerizes in the composition which has a (meth) acrylic-acid alkylester as a main component and does not contain a silane monomer, the resin composition which becomes 5% or less of solvent insoluble content is obtained. It relates to a water-dispersible pressure-sensitive adhesive composition (claim 2), characterized in that the polymer is obtained by copolymerizing a monomer mixture and 0.005 to 1 parts by weight of a silane monomer based on 100 parts by weight of the monomer mixture under the same conditions as described above.

In addition, the present invention relates to 100 parts by weight of a polymer obtained by copolymerizing a monomer mixture containing (meth) acrylic acid alkyl ester as a main component and containing a silane monomer as the water-dispersible pressure-sensitive adhesive composition. The present invention relates to a water-dispersible pressure-sensitive adhesive composition (Claim 3) formed by adding 0.005 to 1 parts by weight of an organic compound that can be used, and more particularly, to a water-dispersible pressure-sensitive adhesive composition (Claim 4) wherein the organic compound capable of bonding with the silane monomer is a silane compound. will be.

In addition, the present invention relates to a water-dispersible pressure-sensitive adhesive composition (claim 5) in which the silane-based monomer is a methoxy silane-based monomer, wherein the methacrylic acid is copolymerized in the polymer. It relates to an adhesive composition (claim 6).

The present invention also relates to a water-dispersible pressure-sensitive adhesive composition (claim 7) wherein the tackifier is a rosin phenol-based or terpene phenol-based tackifier.

Moreover, this invention relates to the adhesive sheet provided with the adhesive layer which consists of said water-dispersible adhesive composition in one side (claim 8) or both surfaces (claim 9) of a base material.

In addition, the present invention is provided with a pressure-sensitive adhesive layer made of the water-dispersible pressure-sensitive adhesive composition on one side or both sides of the rubber foam (claim 10) and the pressure-sensitive adhesive sheet on one side or both sides of the rubber foam It is related with the rubber foam adhesive sheet (claim 11) characterized by including.                         

In the present specification, the term "solvent insoluble" refers to a sample of a predetermined amount (approximately 500 mg) (the weight of the nonvolatile matter is referred to as W ₁ mg), and this is immersed in ethyl acetate for 3 days at room temperature. The insolubles were taken out and the insolubles were dried at 100 ° C. for 2 hours to measure the weight (W ₂ mg), which was calculated according to the following equation:

The present invention provides a water-dispersible pressure-sensitive adhesive composition comprising a (meth) acrylic acid alkyl ester as a main component and adding a tackifier containing a phenol skeleton to an aqueous dispersion of a polymer obtained by copolymerizing a monomer mixture containing a silane monomer. to provide.

As an example of the (meth) acrylic-acid alkylester used as a main component monomer in this invention, the compound represented by following General formula (1) is mentioned:

CH ₂ = C (R ₁ ) COOR ₂

(Wherein R ₁ is a hydrogen atom or a methyl group, and R ₂ represents an alkyl group having 2 to 14 carbon atoms)

Examples of R ₂ include ethyl, propyl, isopropyl, butyl, isobutyl, isoamyl, hexyl, heptyl, 2-ethylhexyl, isooctyl, isononyl, isodecyl and the like. It can be illustrated. Among these, C2-C10 alkyl groups, such as a butyl group and 2-ethylhexyl group, are preferable as R <_2> . The said (meth) acrylic-acid alkylester can be used individually or in mixture of 2 or more types. For example, butyl acrylate alone or a combination of butyl acrylate and 2-ethylhexyl acrylate can be used as the alkyl acrylate. In this case, the ratio of 2-ethylhexyl acrylate and butyl acrylate is about the former / the latter = 0/100-55/45 (for example, 5/95-60/40).

The proportion of the (meth) acrylic acid alkyl ester [eg, the (meth) acrylic acid C _2-14 alkyl ester] in the monomer mixture containing (meth) acrylic acid alkyl ester as a main component is generally 80% by weight or more (eg, 80 to 99.8). By weight), preferably at least 85% by weight (eg, about 85 to 99.5% by weight), more preferably at least 90% by weight (eg, about 90 to 99% by weight).

The monomer mixture usually contains a functional group-containing monomer (thermal crosslinkable functional group-containing monomer) to reach a crosslinking point for thermal crosslinking. By using the functional group-containing monomer as a comonomer component, the adhesion to the adherend is also improved.

As said functional group containing monomer, For example, Carboxyl group containing monomers, such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, crotonic acid, maleic anhydride, or its acid anhydride; Hydroxyl group-containing monomers such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 2-hydroxybutyl (meth) acrylate; (Meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, etc. Amide group-containing monomers; Amino group-containing monomers such as dimethylaminoethyl (meth) acrylate and t-butylaminoethyl (meth) acrylate; Glycidyl group-containing monomers such as glycidyl (meth) acrylate; (Meth) acrylonitrile, N- (meth) acryloyl morpholine, N-vinyl-2-pyrrolidone, etc. are mentioned. Among these, carboxyl group-containing monomers such as acrylic acid or acid anhydrides thereof are preferable. The functional group-containing monomer may be used alone or in combination of two or more.

The usage-amount of the said functional group containing monomer is 0.5-12 weight part, Preferably it is about 1-8 weight part with respect to 100 weight part of said (meth) acrylic-acid alkylesters.

In addition, the monomer mixture may contain other copolymerizable monomers, if necessary, in order to enhance properties such as cohesion. As such a copolymerizable monomer, For example, vinyl esters, such as methyl (meth) acrylate and a vinyl acetate; Aromatic vinyl compounds such as styrene and vinyltoluene; (Meth) acrylic acid esters of cyclic alcohols such as cyclopentyldi (meth) acrylate and isobonyl (meth) acrylate; Neopentyl glycol di (meth) acrylate, hexanediol di (meth) acrylate, propylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylol methane tri (meth) acrylate, di (Meth) acrylic acid ester of polyhydric alcohols, such as pentaerythritol hexa (meth) acrylate, etc. are mentioned. These copolymerizable monomers can also be used by 1 type (s) or 2 or more types.

In the present invention, the silane-based monomer copolymerized with the (meth) acrylic acid alkyl ester is not particularly limited as long as it is a polymerizable compound having a silicon atom, but in view of excellent copolymerizability with respect to the (meth) acrylic acid alkyl ester (meth) Silane compounds having a (meth) acryloyl group, such as a) acryloyloxyalkylsilane derivative, are preferable. Examples of the silane monomers include 3-methacryloyloxypropyltrimethoxysilane, 3-acryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, and 3-acryloyloxy. Propyltriethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, 3-acryloyloxypropylmethyldimethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, 3-acryloyloxy Propylmethyldiethoxysilane, etc. are mentioned. These silane monomers can be used individually or in combination of 2 or more types.

Moreover, as a silane monomer copolymerizable other than the above, for example, vinyl trimethoxysilane, vinyl triethoxysilane, 4-vinyl butyl trimethoxysilane, 4-vinyl butyl triethoxysilane, 8-vinyl octyl trimethoxysilane , 8-vinyloctyltriethoxysilane, 10-methacryloyloxydecyltrimethoxysilane, 10-acryloyloxydecyltrimethoxysilane, 10-methacryloyloxydecyltriethoxysilane, 10- Acryloyloxydecyl triethoxysilane etc. can also be used.

Although the quantity of a silane monomer can be suitably selected according to the kind, use, etc. of the said (meth) acrylic-acid alkylester, the monomer mixture (except a silane monomer) whose copolymerization amount of a silane monomer is a main component of the said (meth) acrylic-acid alkylester) When it exceeds 1 weight part with respect to 100 weight part, adhesive force may fall to the extent to which it can not adhere | attach, and when it is less than 0.005 weight part, cohesion force will fall easily due to lack of polymer strength. Therefore, in the present invention, the amount of the silane monomer with respect to 100 parts by weight of the monomer mixture (excluding the silane monomer) is preferably 0.005 to 1 parts by weight, more preferably 0.01 to 0.5 parts by weight.

The polymer constituting the water-dispersible pressure-sensitive adhesive composition of the present invention is, for example, a (meth) acrylic acid ester copolymer according to an emulsion polymerization in which a monomer mixture containing, as the main component, the alkyl (meth) acrylic acid ester and a silane monomer is usually used. It can be prepared as an aqueous dispersion of.

In the water-dispersible pressure-sensitive adhesive composition of the present invention, a resin composition having a solvent-insoluble content of 5% or less is obtained, in particular, when polymerizing in a composition containing (meth) acrylic acid alkyl ester as a main component and not containing a silane monomer. Water-dissipation-type pressure-sensitive pressure containing the monomer mixture to be obtained and the polymer obtained by polymerization under the same conditions as the polymerization of 0.005 to 1 parts by weight of the silane monomer with respect to 100 parts by weight of the monomer mixture in a composition that does not contain the silane monomer. In the adhesive composition, it is possible to achieve excellent terminal peelability and high retention even though it is a water dispersion type.

Said "under the same conditions" means that the same polymerization conditions other than the presence or absence of a silane monomer, such as reaction temperature, reaction time, the kind and usage-amount of a polymerization initiator, the kind and usage-amount of a chain transfer agent, etc. are the same.

Moreover, when superposing | polymerizing in the composition which does not contain a silane monomer, when peeling the monomer mixture and silane monomer from which the resin composition in which a solvent insoluble content exceeds 5% is obtained, terminal peelability will fall easily.

The emulsion polymerization system that can be used in the present invention is general batch polymerization, continuous drop polymerization, split drop polymerization, or the like, and the polymerization temperature is, for example, about 20 to 100 ° C.

As a polymerization initiator used for superposition | polymerization, a 2,2'- azobisisobutylonitrile, 2,2'- azobis (2-methylpropionamidine) disulfate, 2,2'- azobis (2-ami Dinopropane) dihydrochloride, 2,2'-azobis [2- (5-methyl-2-imidazolin-2-yl) propane] dihydrochloride, 2,2'-azobis (N, N ' Azo initiators such as dimethylene isobutyl amidine; Persulfates such as potassium persulfate and ammonium persulfate; Peroxide initiators such as benzoyl peroxide, t-butyl hydroperoxide and hydrogen peroxide; Substituted ethane-based initiators such as phenyl substituted ethane; Aromatic carbonyl compounds; Redox initiators, such as the combination of a persulfate and sodium hydrogen sulfite, and a combination of a peroxide and sodium ascorbate, etc. are mentioned, It is not limited to these. The usage-amount of a polymerization initiator is about 0.005-1 weight part with respect to 100 weight part of total amounts of a monomer mixture.

In addition, a chain transfer agent can be used for superposition | polymerization. Examples of the chain transfer agent include chain transfer agents commonly used, such as mercaptans such as dodecanethiol. The amount of the chain transfer agent used is, for example, about 0.001 to 0.5 parts by weight based on 100 parts by weight of the total amount of the monomer mixture.

As the emulsifier, anionic emulsifiers such as sodium lauryl sulfate, ammonium lauryl sulfate, sodium dodecylbenzene sulfonate, sodium polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl phenyl ether ammonium sulfate and polyoxyethylene alkyl phenyl ether sodium sulfate; Nonionic emulsifiers, such as a polyoxy ethylene alkyl ether and polyoxyethylene alkyl phenyl ether, etc. can be used. These emulsifiers may be used independently and may use 2 or more types together. The amount of the emulsifier used is, for example, 0.2 to 10 parts by weight, preferably about 0.5 to 5 parts by weight, based on 100 parts by weight of the total amount of the monomer mixture.

In addition, the water-dispersible pressure-sensitive adhesive composition of the present invention can obtain the (meth) acrylic acid ester copolymer by a method other than the emulsion polymerization in addition to the production method by the emulsion polymerization, and then disperse in water with an emulsifier to prepare an aqueous dispersion. Can be.

The water-dispersible pressure-sensitive adhesive composition of the present invention is the number of (meth) acrylic acid ester copolymers containing the silane monomers in order to prevent delamination over time with respect to the release liner and the backing layer to which the silicone-based release agent is applied. An organic compound capable of bonding with the silane monomer can be added to the dispersion. An organic compound capable of binding to a silane monomer may be an active group (eg, a hydroxyl group or a reactive group that reacts with a Si-OH group generated by hydrolyzing a Si-OR group (R is an alkyl group such as methyl or ethyl) of the silane monomer). Although it does not specifically limit if it has a carboxyl group), The silane compound with favorable reactivity with a silane monomer is preferable.

The silane compound is a compound having a Si—H group, a Si—OH group, and a Si—OR group (R is an alkyl group such as methyl or ethyl) in a molecule, for example, methyltrimethoxysilane, butyltrimethoxysilane, and dodecyl tree. Methoxysilane, hexadecyltrimethoxysilane, octadecyldimethylmethoxysilane, dimethoxydimethylsilane, methoxytrimethylsilane, diethoxydimethylsilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane , Dimethoxydiphenylsilane, diphenylethoxy methylsilane, dimethoxymethylphenylsilane, triethylsilane, tripropylsilane, trimethylsilolol, triethylsilolol and the like.

It is preferable that the said silane compound does not have a functional group which reacts with a polymer, but it does not matter if it is a functional group which does not react remarkably. As a silane compound which has such a functional group, (meth) acrylic-acid silane compounds, such as 3-methacryloyloxypropyl trimethoxysilane and 3-acryloyloxypropyl trimethoxysilane, and dimethoxy-3- mercapto, for example. Propylmethylsilane, 3-mercaptopropyltrimethoxysilane, and the like. These silane compounds can be used independently and can use 2 or more types together.

If the amount of the organic compound that can be bonded to the silane monomer is less than 0.005 parts by weight based on 100 parts by weight of the polymer containing (meth) acrylic acid alkyl ester as the main component, heavy peeling may not be prevented. Moreover, when it exceeds 1 weight part, cohesion force may fall, the contamination to a to-be-adhered body may arise, and when using the organic compound which can couple | bond with a polyfunctional silane type monomer, peeling may become heavy on the contrary. This is presumably because the unreacted organic compound acts as a crosslinking agent. Therefore, in this invention, it is preferable that the quantity of the organic compound which can couple | bond with a silane monomer with respect to 100 weight part of said polymers is 0.005-1 weight part, More preferably, it is the range of 0.01-0.5 weight part.

In addition, in this invention, in order to prevent the time-lapse peeling with respect to the peeling liner and backing layer which apply | coated the silicone type peeling agent, the monomer mixture which makes the (meth) acrylic-acid alkylester the main component and also contains a silane monomer is copolymerized. In the polymer obtained, it is preferable to use a methoxysilane monomer in which R of the Si—OR group of the silane monomer is a methyl group as the silane monomer copolymerized with the above-mentioned (meth) acrylic acid alkyl ester. Examples of the methoxy silane monomers include 3-methacryloyloxypropyltrimethoxysilane, 3-acryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropylmethyldimethoxysilane, and 3-acryloyl. Oxypropylmethyldimethoxysilane, vinyltrimethoxysilane, 4-vinylbutyltrimethoxysilane, 8-vinyloctyltrimethoxysilane, 10-methacryloyloxydecyltrimethoxysilane, 10-acryloyloxyde Siltrimethoxysilane etc. are mentioned.

When methoxysilane-based monomers are used, the methoxysilane-based monomers have a high rate of hydrolysis and most of the methoxy groups hydrolyze into silanol groups during polymerization, so that most of the silane-based monomers incorporated into the polymer during drying are crosslinked. It is presumed that the silane monomers that can react with the release layer at the time of preservation decrease by being used for

Moreover, in order to achieve the same objective, in the polymer obtained by copolymerizing the monomer mixture which has (meth) acrylic-acid alkylester as a main component and also contains a silane monomer, using methacrylic acid as said functional group containing monomer is preferable. desirable. In the case of using a polymer copolymerized with methacrylic acid, it is possible to prevent an increase in the peeling force, since the methacrylic acid is more hydrophobic than acrylic acid in the aqueous dispersion and is distributed to the inside of the fine particles, thereby preventing hydrolysis of the silane monomers embedded in the polymer. It is presumably because it promotes.

In this invention, a crosslinking agent can be used according to the use of an adhesive. As said crosslinking agent, the crosslinking agent used normally can be used, For example, an isocyanate type crosslinking agent, an epoxy type crosslinking agent, an oxazoline type crosslinking agent, an aziridine type crosslinking agent, a metal chelate type crosslinking agent, etc. are mentioned. The crosslinking agent may use any of oil solubility and water solubility.

The water dispersion type adhesive composition of this invention is formed by adding the tackifier containing a phenol skeleton to the water dispersion of the (meth) acrylic acid ester polymer containing the said silane type monomer.

The tackifier used for this invention is a compound containing a phenol skeleton in a molecule | numerator, For example, rosin phenol resin, a terpene phenol resin, an alkyl phenol resin, etc. are mentioned.

Examples of the rosin phenol resin of the present invention include Arakawa Chemical Industry Co., Ltd. "Tamanol", Sumikomo Durez Co., Ltd. "Sumilite Resin", and the like; As terpene phenol resin, Yashara Chemical Co., Ltd. product "nanoret", "YS polyster", "Mighties", etc .; As the alkylphenol resin, commercially available products such as Hitachi Chemical Co., Ltd. "Hitanol", Sumitomo Chemical Co., Ltd. "Takkirol", and Murai Chemical Co., Ltd. "PP Series" can be used. These tackifiers may be used independently and may use 2 or more types together.

If the amount of the tackifier is less than 5 parts by weight or more than 50 parts by weight with respect to 100 parts by weight of the polymer containing the (meth) acrylic acid alkyl ester as a main component, practically sufficient adhesive properties are not obtained. Adhesiveness may be inadequate. Therefore, in the present invention, the amount of the tackifier to 100 parts by weight of the polymer is preferably 5 to 50 parts by weight, more preferably in the range of 10 to 40 parts by weight.

In addition, additives commonly used in pressure-sensitive adhesives, such as anti-aging agents, fillers, pigments, colorants, and the like may be added to the water-dispersible pressure-sensitive adhesive composition of the present invention.

In addition, in order to stabilize the particles in the water-dispersible pressure-sensitive adhesive composition of the present invention, the pH is usually adjusted to 7-9 using a base such as ammonia. In this case, when there is much residual ammonia, since the delamination progresses with respect to the peeling liner which applied the silicone type | system | group peeling agent, and a back processing layer over time, it is preferable that the addition amount is small, and pH is about 7-8 more preferable.

Next, an example of the adhesive sheet of this invention is demonstrated according to drawing. However, the present invention is not limited by these.

The adhesive sheet of this invention consists of a structure provided with the adhesive layer which consists of said water-dispersible adhesive composition in one side or both sides of a base material. BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows an example of the adhesive sheet which has an adhesive layer on both surfaces of a base film.

In FIG. 1, (5) represents an adhesive sheet, (1) represents the adhesive layer which consists of said water-dispersible adhesive composition, (2) represents the base material, and (3) has shown the peeling liner, respectively. The adhesive sheet 5 is based on a water-dispersible pressure-sensitive adhesive composition comprising a silane monomer and adding a tackifier containing a phenol skeleton to a copolymer of a monomer mixture composed mainly of (meth) acrylic acid alkyl esters. It is obtained by applying onto a substrate and thermally crosslinking to form the pressure-sensitive adhesive layer 1. Thereafter, it is adhered to the release liner 3 for protecting the adhesive face. This is preferably wound as shown, but can be stored as it is. Moreover, after forming the adhesive layer 1 on the peeling liner 3, you may make it adhere | attach with the base material 2.

In the present invention, the substrate 2 is, for example, plastic films such as polypropylene film, ethylene-propylene copolymer film, polyester film, polyvinyl chloride and the like; Papers such as conventional Japanese paper and kraft paper; Textiles such as cotton and staple fibers; Nonwovens such as polyester nonwovens and vinylon nonwovens; Metal foil etc. can be used. The plastic film may be any of an unstretched film and a stretched (uniaxially stretched or biaxially stretched) film. Moreover, the surface treatment by the commonly used undercoat, corona discharge system, etc. may be given to the surface which apply | coats an adhesive in a base material. Although the thickness of a base material can be suitably selected according to the objective, it is generally about 10-500 micrometers.

The pressure-sensitive adhesive layer 1 may be formed by using a coater commonly used, such as a gravure roll coater, a reverse roll coater, a kiss roll coater, a dip roll coater, a bar coater, a knife coater, a spray coater, or the like. It can obtain by apply | coating an aqueous dispersion type adhesive composition to the base material 2. The water-dispersible pressure-sensitive adhesive composition is applied so that the thickness of the pressure-sensitive adhesive layer after drying is, for example, about 10 to 100 μm.

The applied water-dispersible pressure-sensitive adhesive composition is heat crosslinked by heating to form the pressure-sensitive adhesive layer (1). Thermal crosslinking is carried out by heating to a temperature at which the crosslinking reaction proceeds according to a commonly used method such as a silane monomer or a crosslinking agent. The solvent insoluble content of the adhesive layer after crosslinking is about 15 to 70 weight%, for example. The molecular weight (weight average molecular weight; in terms of standard polystyrene) of the solvent soluble portion of the pressure-sensitive adhesive layer after crosslinking is, for example, about 100000 to 600000, preferably about 200000 to 450000. The molecular weight of the solvent insoluble fraction and the solvent soluble portion of the pressure-sensitive adhesive layer after crosslinking is, for example, the ratio of the silane monomer or functional group-containing monomer to the total amount of the monomer mixture, the type and amount of the chain transfer agent or the crosslinking agent, in particular the silane monomer and the chain transfer agent. It can set arbitrarily by adjusting an amount suitably.

In the present invention, the release liner 3 is provided with a release layer made of a silicone release agent, a long chain alkyl release agent, a fluorine release agent, or the like on one side or both sides of the thin base material, and a conventionally used one is used. Although the thickness is not specifically limited, Preferably it is 15 micrometers or more, More preferably, it is 25-500 micrometers.

2 is a cross-sectional view schematically showing another example of the pressure-sensitive adhesive sheet of the present invention, wherein the pressure-sensitive adhesive layer 1 is provided on one side of the base material 2, and the pressure-sensitive adhesive composition different from the pressure-sensitive adhesive layer 1 on the other side. The adhesive layer 4 which consists of these is provided, and the adhesive sheet 6 is formed. And the peeling liner 3 is stuck in order to protect an adhesive surface. Although the adhesive layer 4 is not specifically limited here, According to the use and the kind of to-be-adhered body, conventionally well-known adhesive composition, such as acrylic type, rubber type, and silicone type, can be used. This is preferably wound as shown, but can be stored as it is. In addition, although the peeling liner 3 is comprised in FIG. 2 in contact with the adhesive layer 4, it may be comprised in contact with the adhesive layer 1. In this case, the structure can be changed according to the kind of to-be-adhered body which affixes an adhesive sheet initially.

3 is a cross-sectional view schematically showing still another example of the pressure-sensitive adhesive sheet of the present invention, wherein the pressure-sensitive adhesive layer 1 is provided on one side of the base material 2, and the release liner 3 is attached thereto. Shows. This is preferably wound as shown, but can be stored as it is.

4 is a cross-sectional view schematically showing still another example of the pressure-sensitive adhesive sheet of the present invention, showing a structure in which the pressure-sensitive adhesive layer 1 is attached to the base material 2 provided with the back treatment layer 7. As shown in the figure, the adhesive layer 1 is wound around the back treatment layer 4 to be stored.

In this invention, what provided the base material 1 with the silicone type peeling agent, the long-chain alkyl type peeling agent, the fluorine type peeling agent etc. according to a conventionally well-known method can be used for the back processing layer 7.

The adhesive sheet of the present invention has excellent adhesion to the rubber foam, and is usually 3N / 20mm or more, preferably 4N / 20mm or more, and more preferably 5N / 20mm or more (180 degree peeling, peeling speed 300mm /). Min, 23 ° C., in 60% RH atmosphere).

In addition, the present invention is provided with a rubber foam adhesive sheet, characterized in that the pressure-sensitive adhesive layer made of the water-dispersible pressure-sensitive adhesive composition on one side or both sides of the rubber foam, and the adhesive sheet provided on one side or both sides of the rubber foam The rubber foam adhesive sheet characterized by the above-mentioned.

FIG. 5 is a cross-sectional view schematically showing an example of a rubber foam pressure sensitive adhesive sheet provided with the pressure sensitive adhesive sheet 5 illustrated in FIG. 1 on one surface of the rubber foam. In FIG. 5, (8) represents a rubber foam, and others are as above-mentioned. In addition, the adhesive sheet 5 may be provided on both surfaces of the rubber foam 8.

FIG. 6 is a cross-sectional view showing still another example of the foamed pressure-sensitive adhesive sheet of the present invention, and is provided with the pressure-sensitive adhesive sheet 6 illustrated in FIG. 2 on one side of the rubber foam 8. In this case, the pressure sensitive adhesive sheet 6 is configured to be bonded to the foam 8 through the pressure sensitive adhesive layer 1. In addition, the adhesive sheet 6 may be provided on both sides of the rubber foam 8.

In addition, this invention can also be made into what is called a base-less double-sided adhesive sheet which does not contain a base material by forming the adhesive layer 1 on the peeling liner 3. This can be made into the rubber foam adhesive sheet which provided the adhesive layer which consists of a water-dispersible adhesive composition on one side (or both sides) of a rubber foam, for example, by sticking with the foam 8 like sectional drawing shown in FIG.

In the present invention, the rubber foam 8 can be obtained by vulcanizing and foaming a mixture containing a rubber polymer, a vulcanizing agent, a foaming agent, a vulcanization accelerator, a foaming aid and the like by heating.

The rubber polymer is not particularly limited, and conventionally known suitable ones can be used, for example, ethylene propylene diene rubber (EPDM) and ethylene propylene rubber, ethylene propylene polymer and silicone rubber, fluorine rubber and acrylic rubber, polyurethane type Rubber and polyamide-based rubber, natural rubber and polyisobutylene, polyisoprene and chloroprene rubber, butyl rubber and nitrile butyl rubber, styrene butadiene rubber and styrene butadiene styrene rubber, styrene isoprene styrene rubber and styrene ethylene Non-conjugated such as butadiene rubber, styrene, ethylene, butylene, styrene rubber and styrene, isoprene, propylene, styrene rubber, alpha-olefins such as chlorosulfonated polyethylene and butene-1, dicyclopentadiene and ethylene norbornene The cyclic or acyclic polyene having a heavy bond as a component And the like can be mentioned rubber-based copolymers. EPDM is preferable in view of practicality.

The vulcanizing agent is also not particularly limited, and any conventionally known suitable one can be used, such as sulfur, sulfur compounds, selenium, magnesium oxide, zinc monoxide, zinc oxide, organic peroxides, polyamines, and oximes (eg p-quinones). Oxime, p, p'-dibenzoylquinone dioxime, etc.), nitroso compounds (e.g. p-dinitrosobenzine), resins (e.g., alkylphenol-formaldehyde resins, melamine-formaldehyde condensates, etc.) And ammonium salts (for example, ammonium benzoate).

These vulcanizing agents can be used by appropriately selecting one kind or two kinds or more, and sulfur or sulfur compounds, in particular, sulfur can be preferably used in view of physical properties such as durability due to vulcanization and foamability of the obtained rubber foam. have. The amount of vulcanizing agent can be appropriately determined depending on the vulcanization efficiency and the like based on the type thereof. For example, in the case of sulfur or sulfur compounds, 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, is used per 100 parts by weight of the rubber polymer. .

Moreover, there is no restriction | limiting in particular as a foaming agent, For example, an inorganic foaming agent or an organic foaming agent can be used.

As the inorganic blowing agent, for example, ammonium carbonate, ammonium bicarbonate, sodium bicarbonate, ammonium nitrite, sodium borohydride, azide and the like are used. As the organic blowing agent, for example, azo compounds (e.g., azobisisobutyronitrile, azodicarboxylic acid amide (ADCA), barium azodicarboxylate, etc.), alkanes fluorides (e.g. trichloromonofluoromethane, dichloromonofluoro Romethane, etc.), hydrazine-based compounds (e.g., paratoluenesulfonylhydrazide, diphenylsulfone-3,3'-disulfonylhydrazide, 4,4'-oxybis (benzenesulfonylhydrazide), Etc.), semicarbazide compounds (e.g. p-toluylenesulfonyl semicarbazide, 4,4'-oxybis (benzenesulfonyl semicarbazide), etc.), triazole compounds (e.g. 5-morpholyl- 1,2,3,4-thiatriazole), N-nitroso-based compound (N, N'-dinirosopentamethylenetetramine, N, N'-dimethyl-N, N'-dinitrosoterephthalamide) Etc. are used.

These foaming agents can be used suitably selecting 1 type, or 2 or more types, and organic foaming agents, such as an azo compound and an N-nitroso type compound, are used preferably from a viewpoint of the physical property resulting from the foamability of the rubber foam obtained. In addition, the blending ratio of the blowing agent can be appropriately determined according to the physical properties of the intended foam, etc., and generally 0.1 to 100 parts by weight, preferably 0.5 to 50 parts by weight, more preferably 1 to 30 parts by weight, based on 100 parts by weight of the rubber polymer. It is wealth.

Moreover, in this rubber foam, it is preferable to mix | blend a foaming adjuvant in order to ensure vulcanization accelerator and favorable foaming so that a vulcanization may be promoted.

Examples of the vulcanization accelerator include dithiocarbamic acids (e.g., sodium dimethyldithiocarbamate, sodium diethyldithiocarbamate, zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate), and thiazoles (e.g., 2-mercaptobenzothiazole, dibenzothiadyl disulfide and the like), guanidines (e.g., diphenylguanidine, di-o-tolylguanidine, etc.), sulfenamides (e.g., benzothiadyl-2-diethylsulfenamide) , N-cyclohexyl-2-benzothiadylsulfenamide, etc.), thiurams (e.g., tetramethylthiuram monosulfide, tetramethylthiuram disulfide, etc.), xanthogenic acids (e.g. sodium isopropyl xanthogenate) , Isopropyl xanthogenic acid, etc.), aldehyde ammonia (e.g., acetaldehyde ammonia, hexamethylenetetramine, etc.), aldehyde amines (e.g., n-butylaldehyde aniline, butylaldehyde monobutylamine, etc.), thiouure Acids (e. G., Diethyl thiourea, trimethyl thiourea, etc.) are used. Such vulcanization accelerators may be used alone or in combination of two or more thereof. For example, it is preferable to use dithiocarbamic acids and thiazoles in view of the vulcanization rate and the like.

In addition, the compounding ratio of the vulcanization accelerator is, for example, 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the rubber polymer in view of the resistance to crushing and the vulcanization rate.

In contrast to vulcanization accelerators, for example, organic acids (e.g., phthalic anhydride, benzoic acid, salicylic acid, etc.) and amines (e.g., N-nitroso-diphenylamine, N-nitroso-phenyl-? -Vulcanization retarders such as naphthylamine) may be suitably blended.

As the foaming aid, for example, a urea compound, a salicylic acid compound, a benzoic acid compound or the like is used. These foaming aids can be used by appropriately selecting one kind or two kinds or more, and the urea-based compound is preferably used in view of having a low effect on vulcanization and a low price. The blending ratio of the foaming aid is, for example, 1 to 15 parts by weight, preferably 2 to 10 parts by weight, more preferably 3 to 8 parts by weight, based on 100 parts by weight of the rubber polymer.

Moreover, it is preferable to mix | blend a filler, processing oil, a lubricating agent, etc. according to the use, and this rubber foam can also mix | blend well-known additives, such as a plasticizer, a flame retardant, antioxidant, antioxidant, a pigment, a coloring agent, and an antifungal agent suitably, for example. It may be.

As the filler, for example, zincated, carbon black, calcium carbonate, magnesium carbonate, silicic acid or salts thereof, talc, mica, bentonite, silica, alumina, aluminum silicate, acetylene black, aluminum powder and the like are used. These fillers can be suitably selected from 1 type, or 2 or more types, and since zincification acts also as a stabilizer and carbon black also acts as a reinforcing material, it is used preferably. In general, calcium carbonate is commonly used. The blending ratio of the filler is, for example, 80 to 200 parts by weight, preferably 10 to 180 parts by weight based on 100 parts by weight of the rubber polymer.

Paraffin oil, petroleum oil, etc. are used as a process oil, Preferably process oil is used. The blending ratio of the processing oil is, for example, 10 to 60 parts by weight, preferably 30 to 50 parts by weight based on 100 parts by weight of the rubber polymer. By adding the processing oil, kneading and foaming of the blend are facilitated.

As the lubricant, for example, stearic acid or esters thereof are used, and the blending ratio thereof is, for example, 1 to 5 parts by weight, preferably 2 to 4 parts by weight based on 100 parts by weight of the rubber polymer. By adding a lubricant, for example, it is difficult to adhere to the roll during kneading and the workability can be improved.

As the plasticizer, for example, paraffins (e.g. chlorinated paraffin), waxes, naphthenes, aromatics, asphalts, dry oils (e.g. linseed oil), animal and vegetable oils, low molecular weight polymers, phthalic acid esters, and phosphate esters , Alkyl sulfonic acid esters, tackifiers and the like are used. By adding a plasticizer, a blend becomes soft and it becomes easy to foam.

As the flame retardant, for example, aluminum hydroxide, magnesium hydroxide and the like are used.

In addition, the rubber foam may suitably include a non-rubber polymer according to its purpose and use, and may be, for example, an acrylic polymer (eg, poly (meth) acrylic acid alkyl ester), polyvinyl chloride, polyethylene, polypropylene, ethylene-vinyl acetate. Copolymer, polyvinyl acetate, polyamide, polyester, chlorinated polyethylene, urethane polymer, styrene polymer, silicone polymer, epoxy resin and the like are used.

These non-rubber polymers may be appropriately selected from one kind or two or more kinds according to the purpose and use thereof, and the blending ratio thereof is, for example, 50 wt% or less, preferably 30 wt% or less, more preferably, of the rubber polymer. It is 15 weight% or less.

In the preparation of the blend of the rubber foam of the present invention, first, the blended ingredients such as rubber-based polymers, vulcanizing aids, fillers, and processing oils are kneaded, for example, by kneading such as kneaders and mixing rolls to adjust the blends. do. Moreover, in this kneading, it can also heat suitably. Subsequently, it is preferable to further select and mix a vulcanizing agent, a foaming agent, and a foaming adjuvant appropriately to this blend, and to further heat it after kneading this using a mixing roll or the like.

Formation of the rubber foam of the present invention can be carried out by heating and vulcanizing the above-mentioned admixture, but at the time of formation, the admixture is formed into a predetermined form such as a sheet, if necessary, and the molded product is subjected to heat treatment. To form a vulcanized foam. In that case, it is preferable that the molded object was molded in an arbitrary form in a suitable manner, and there is no particular limitation regarding the form.

Therefore, the molded body before the vulcanization and foaming treatment may be formed into a sheet or other form in a suitable manner, for example, by mixing rolls, calendar rolls, extrusion molding, or the like. It may be molded in a predetermined form having irregularities and the like in a manner.

In the above-described formation of a foam having an uneven shape, a method in which a vulcanized state is placed on a mold having an uneven shape and heated, and a vulcanized foaming process is carried out by flowing a mixture that forms the molded product into the uneven shape of the mold is flowable. Can be. This method has the advantage that even in the case of a frame having a complicated deep concave-convex structure having a corrugated structure, the concave-convex shape can be formed with high precision.

Therefore, the dimension of a molded object is arbitrary and can be suitably determined according to the form of the rubber foam made into the objective, and the like. In the case of sheets or the like, the thickness thereof is generally 100 mm or less, preferably 1 μm to 80 mm, especially 10 μm to 50 mm.

The above-mentioned vulcanization foaming process can be performed on suitable conditions according to a prior art by the vulcanization start temperature, foaming temperature, etc. by the used vulcanizing agent, foaming agent, etc. Typical vulcanization foaming temperatures are about 200 ° C. or less, preferably 120 to 180 ° C. The vulcanized foaming process softens the admixture, decomposes the blowing agent, and forms a foamed structure, whereby vulcanization proceeds to form a desired vulcanized foam. The vulcanization foaming treatment can also be performed under pressure for the purpose of adjusting the expansion ratio. The pressurization condition follows the conventional method.

The expansion ratio (density ratio before and after the foaming) of the rubber foam to be formed is appropriately determined according to the purpose of use and the like. Generally, the density is 0.5 g / cm ³ or less, preferably 0.20 g / cm ³ or less, and more preferably 0.15 g / cm ³ or less. Such density can be controlled by adjusting the expansion ratio and the like by the blending amount of the blowing agent described above, the processing time and temperature of the vulcanized foam, and the like. In addition, it is possible to control the foaming structure such as independence or continuity of the vulcanized foam, or mixture thereof by adjusting the expansion ratio.

Since the rubber foam adhesive sheet which concerns on this invention uses an acrylic adhesive of a water dispersion type | mold, it can obtain the rubber foam adhesive sheet which is preferable for environmental hygiene, extremely excellent terminal peeling property and retention property is achieved, and the adhesive force with stability with time is stable. Therefore, it can be used for various uses according to conventional techniques, such as a cushioning material, a pad material, sealing materials for various purposes, such as airtightness and waterproofing, a vibration reducing material, such as a heat insulating material, soundproofing, and vibration suppression.

Example

The present invention is explained in more detail by the following examples. However, the present invention is not limited to these examples. In addition, "part" and "%" are a basis of weight unless there is particular notice.

Example 1

Using a reaction vessel equipped with a cooling tube, a nitrogen introduction tube, a thermometer, and a stirrer, 70 parts of butyl acrylate, 30 parts of 2-ethylhexyl acrylate, 3 parts of acrylate, 3-methacryloyloxypropyltrimethoxysilane (Shin-Etsu) KBM-503 manufactured by Silicone Co., Ltd.) 0.05 part, Dodecanethiol (chain transfer agent) 0.05 part, 2,2'-azobis [2- (5-methyl-2-imidazolin-2-yl) propane] di 0.1 part of hydrochloride (initiator) was added to 100 parts of water to which 1.5 parts of sodium polyoxyethylene lauryl sulfate (emulsifier) was added, followed by emulsion polymerization to obtain a polymer. In addition, the solvent insoluble content of the polymer at the time of completion | finish of superposition | polymerization in the case of superposing | polymerizing in the composition which does not mix a silane monomer similarly was 0%.

10% ammonium water was added thereto, the pH was adjusted to 8, and then 0.06 parts of n-decyltrimethoxysilane (AY43-210MC, manufactured by Dow Corning Silicon Co., Ltd.) was added as a silane compound to obtain an aqueous dispersion. did. To this 100 parts of solid content, 30 parts of rosin phenol-based resin ("Tamanol E-100" manufactured by Arakawa Chemical Industry Co., Ltd.) was added as a tackifier to obtain a water-dispersible pressure-sensitive adhesive.

This was coated on the heavy peeling surface of the peeling liner (SLB-80W5D manufactured by Kite Chemical Industry Co., Ltd.) coated with a silicone-based release agent, dried at 120 ° C. for 3 minutes, and provided with a pressure-sensitive adhesive layer having a thickness of 70 μm. did. This adhesive sheet was adhered to both surfaces of the nonwoven fabric (PR-1L manufactured by Nippon Paperboard Co., Ltd.) to prepare an adhesive sheet.

Example 2

In Example 1, a rosin phenolic resin (Sumilite Resin PR12603, manufactured by Sumitomo Durets, Inc.) was added instead of adding a rosin phenolic resin (Tamanole E-100, manufactured by Arakawa Chemical Industries, Ltd.) as a tackifier. A pressure-sensitive adhesive sheet was produced in the same manner as in Example 1, except that 30 parts of the aqueous dispersion was added as a solid content.

Example 3

Instead of adding a rosin phenolic resin (Tamanol E-100, manufactured by Arakawa Chemical Industry Co., Ltd.) as a tackifier in Example 1, a terpene phenolic resin (Nanoret G 1450, manufactured by Yashara Chemical Co., Ltd.) An adhesive sheet was produced in the same manner as in Example 1 except that 30 parts of the aqueous dispersion was added as a solid content.

Comparative Example 1

Instead of adding rosin phenolic resin ("Tamanol E-100" manufactured by Arakawa Chemical Industry Co., Ltd.) as the tackifier in Example 1, polymerized rosin ester resin ("Superester E-625" manufactured by Arakawa Chemical Industry Co., Ltd.). ) Was prepared in the same manner as in Example 1 except that 30 parts of) were added as a solid content.

Comparative Example 2

In the said Example 1, the adhesive sheet was produced like Example 1 except not having added a tackifier.

Comparative Example 3

70 parts of butyl acrylate, 30 parts of 2-ethylhexyl acrylates, 3 parts of acrylic acid, 0.07 parts of dodecane thiol (chain transfer agent) using the reaction vessel provided with a cooling tube, a nitrogen introduction tube, a thermometer, and a stirrer. Water to which 0.1 parts of 2'-azobis [2- (5-methyl-2-imidazolin-2-yl) propane] dihydrochloride (initiator) and 1.5 parts of sodium polyoxyethylene nonylphenyl ether (emulsifier) are added It was added to 100 parts and emulsion-polymerized to obtain a polymer.

10 weight% ammonium water was added here and it adjusted to pH8. 30 parts of rosin phenolic resin ("Tamaol E-100" made by Arakawa Chemical Industry Co., Ltd.) is added as a tackifier with respect to 100 parts of solid content, and water-soluble epoxy crosslinking agent (TEPIC: Mitsubishi Gas Chemical Co., Ltd.) Product) was added to prepare a water-dispersible pressure-sensitive adhesive.

This was carried out similarly to Example 1, and the adhesive sheet was produced.

The following characteristics were examined about the adhesive sheet obtained from the above Examples and comparative examples. The results are shown in Table 1.

(Adhesion to rubber foam)

A PET film having a thickness of 40 μm was adhered to one side of the adhesive sheet obtained in Examples and Comparative Examples, and this was cut into a width of 20 mm and a length of 100 mm to prepare a test piece for evaluation. The test piece was pressed by a method of reciprocating a roller of 2 kg once with an EPDM rubber foam containing paraffin oil and asphalt as a plasticizer attached to a metal plate as a adherend, and the force required for peeling after standing at 23 ° C. for 30 minutes. Was measured. Measurement conditions were performed in 180 degree peeling, peeling rate 300 mm / min, 23 degreeC, 60% RH atmosphere using the universal tension tester "TCM-1kNB" by Minebea Inc. (refer FIG. 8).

(Terminal peeling test)

An adhesive sheet obtained in Examples and Comparative Examples was adhered to an EPDM rubber foam (5 mm thick) containing paraffinic oil and asphalt as a plasticizer, and this was cut into a width of 10 mm and a length of 50 mm to prepare a test piece for evaluation. . After attaching one end of this test piece to the edge part of ABS board with the contact area of 10 mm x 10 mm (the outer surface), the remainder (10 mm x 40 mm) was inverted to the inner surface of ABS board, and it adhere | attached. After leaving this at 70 degreeC for 2 hours, the presence or absence of peeling was evaluated from the ABS board of a rubber foam on the outer surface (refer FIG. 9).

(Adhesion of Rubber Foam Adhesive Sheet)

The pressure-sensitive adhesive sheets obtained in Examples and Comparative Examples were adhered to EPDM-based rubber foams (5 mm thick) containing paraffinic oil and asphalt as plasticizers, and cut into 20 mm width and 100 mm length to prepare test pieces for evaluation. did. The test piece was pressed by a method of reciprocating a 2 kg roller once with a SUS plate as a substrate, and left for 30 minutes at 23 ° C. (initial value) and after 7 days in a 60 ° C./90% RH atmosphere (over time). The force required for peeling off after storage was measured. The measurement conditions were performed in 90 degree | times peeling, peeling rate 300mm / min, 23 degreeC, 60% RH atmosphere using the universal tension tester "TCM-1kNB" by Minebea Corporation (refer FIG. 10).

Pressure-sensitive adhesive composition Rubber Foam Adhesive Strength [N / 20mm] Rubber Foam Terminal Peelability Adhesion to SUS Plate Crosslinking method Tackifying resin Initial [N / 20mm] After storage over time [N / 20mm] Example 1 Silanol Rosinphenol 7 ○ 12 12 Example 2 Rosinphenol 6 ○ 12 12 Example 3 Terpene phenol 5 ○ 10 10 Comparative Example 1 Silanol Polymeric rosin ester 8 ○ 12 6 Comparative Example 2 none One × 5 5 Comparative Example 3 Epoxy Rosinphenol 5 × 10 10

As can be clearly seen from Table 1, the water-dispersible pressure-sensitive adhesives of the present invention (Examples 1 to 3) showed satisfactory performance in all of the adhesive strength to the rubber foam, the terminal peelability, and the adhesive strength after aging.

In contrast, Comparative Example 1 using a polymerized rosin ester containing no phenol skeleton as a tackifier showed satisfactory performance to the rubber foam and terminal peelability, but was inferior to the adhesion after time storage. Moreover, the comparative example 2 which does not add a tackifier was inferior to the adhesive force to a rubber foam, and terminal peelability. Further, the water-dispersible pressure-sensitive adhesive (Comparative Example 3) crosslinked using an epoxy-based crosslinking agent without copolymerizing a silane monomer was inferior in terminal peelability.

As described above, the water-dispersible pressure-sensitive adhesive composition of the present invention is preferable for environmental hygiene because it uses an aqueous pressure-sensitive acrylic pressure-sensitive adhesive, and the pressure-sensitive adhesive sheet and the rubber foam pressure-sensitive adhesive sheet provided thereon have excellent adhesion to the rubber foam and terminal peeling. It has the performance, and also shows good adhesion characteristics with good adhesion stability over time.

Claims (11)

A water-dispersible pressure-sensitive adhesive composition formed by adding a tackifier containing a phenol skeleton to an aqueous dispersion of a polymer obtained by copolymerizing a monomer mixture containing (meth) acrylic acid alkyl ester as a main component and containing a silane monomer. The method of claim 1, The polymer is a monomer mixture in which a resin composition in which a solvent-insoluble content is 5% or less is obtained when the polymer is composed of a (meth) acrylic acid alkyl ester as a main component and polymerized in a composition that does not contain a silane monomer, and 100 parts by weight of the monomer mixture. A water-dispersible pressure-sensitive adhesive composition, which is obtained by copolymerizing 0.005 to 1 parts by weight of a silane monomer with respect to parts under the same conditions as described above. The method according to claim 1 or 2, A water-dispersible pressure-sensitive adhesive composition formed by adding 0.005 to 1 part by weight of an organic compound capable of bonding with a silane monomer based on 100 parts by weight of a polymer. The method of claim 3, wherein A water-dispersible pressure-sensitive adhesive composition wherein the organic compound capable of bonding with the silane monomer is a silane compound. The method according to claim 1 or 2, A water-dispersible pressure-sensitive adhesive composition, wherein the silane monomer is a methoxysilane monomer. The method according to claim 1 or 2, Methacrylic acid is copolymerized in a polymer, The water dispersion type adhesive composition characterized by the above-mentioned. The method according to claim 1 or 2, A water dispersion type pressure-sensitive adhesive composition wherein the tackifier is a rosin phenol-based or terpene phenol-based tackifier. An adhesive sheet provided with one side of a base material with the adhesive layer which consists of a water dispersion type adhesive composition of Claim 1. The adhesive sheet provided with the adhesive layer which consists of a water-dispersible adhesive composition of Claim 1 on both surfaces of a base material. A rubber foam pressure sensitive adhesive sheet comprising a pressure-sensitive adhesive layer made of the water-dispersible pressure-sensitive adhesive composition according to claim 1 on one side or both sides of a rubber foam. The rubber foam adhesive sheet which provided the adhesive sheet in any one of Claims 8-9 on one side or both sides of a rubber foam.

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