JP2628478B2 - Adhesive sheet - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a pressure-sensitive adhesive sheet, and more particularly to a pressure-sensitive adhesive sheet excellent in kanji printer suitability.

[Background Art] Adhesive sheets are used after being processed into labels, seals, stickers, patches and the like for a very wide range of uses such as commercial, office and home use.

The pressure-sensitive adhesive sheet has a pressure-sensitive adhesive layer formed between a surface substrate and a release substrate, and a paper, film, metal foil, or the like is used as the surface substrate, and a high-pressure sheet such as glassine paper is used as the release substrate. A material obtained by applying a release agent such as a silicon compound or a fluorine compound to a density base paper, a clay-coated paper, a polylamination base paper, or the like is used. As the adhesive, rubber-based, acrylic-based, vinyl ether-based emulsions,
Various adhesives of a solvent or non-solvent type are used.

Among such adhesive sheets, demand for an adhesive sheet for a kanji printer as a computer output has been rapidly increasing with the development of an information society.

Conventionally, glassine paper has been used as a release substrate for the pressure-sensitive adhesive sheet for this purpose. However, when high-beating, high-density paper such as glassine paper is used in a kanji printer, this paper shrinks more than normal paper when it is dried, so its behavior to heat is excessively sensitive, and therefore, when heat fixing toner, As a result of the movement, troubles such as poor paper feed, paper misalignment, and printing misregistration occur.In addition, due to the high rigidity, stacking failure occurs in the automatic folding stacker, and uneven heat absorption occurs after thermal fixing of the toner, resulting in unevenness. Curling and the like are easily generated, and heat is hardly dissipated, so that toner blocking is easily generated.

In addition, there has been a problem that the pressure-sensitive adhesive label may fall off the release substrate at the transfer portion or the fixing portion (a portion having a large curvature) due to the release force.

"Problems to be solved by the invention" The present invention provides a stacking defect caused by a release sheet,
An object of the present invention is to provide a pressure-sensitive adhesive sheet which improves blocking of unevenness, curl, and toner, and further prevents label from falling off in a printer.

"Means for Solving the Problems" The present invention relates to a pressure-sensitive adhesive sheet obtained by laminating at least an undercoat layer, a release agent layer, a pressure-sensitive adhesive layer and a surface substrate on a release substrate, wherein the main component of the undercoat layer is an emulsifier. 2-10% by weight
Contains an aqueous acrylate copolymer resin having a glass transition temperature of −60 to 20 ° C., and a release substrate having a tension of 1.0 g.
/ cm ³ or less.

[Operation] The configuration of the pressure-sensitive adhesive sheet of the present invention will be described in detail below.

As the undercoating agent used in the present invention, a method for producing the undercoating agent is disclosed from page 6, line 3 to page 12, line 5 of the specification of Japanese Patent Application No. 62-314788 filed by the present inventors. The aqueous acrylate copolymer resin whose main component contains an emulsifier in an amount of 2 to 10% by weight and a glass transition temperature of −60 to 20 ° C. is appropriately selected and used. As the hydrophilic ethylenically unsaturated monomer constituting the specific copolymer resin, for example, acrylic acid, methacrylic acid, crotonic acid,
Maleic acid, itaconic acid, fumaric acid, monoalkyl maleic acid, monoalkyl itaconic acid, ethylenically unsaturated carboxylic acid-containing monomers such as monoalkyl fumaric acid, further sodium vinyl sulfonate, sodium p-styrene sulfonate, 2-acrylamide-2-methylpropanesulfonic acid, acid phosphoxyethyl methacrylate ethanolamine half salt, sodium 3-allyloxy-2-hydroxypropanesulfonate, sodium polyoxyethylene styrenated phenylsulfate, sodium glycerin monoallyl ether monosulfosuccinate Sodium salt of 2-sulfoethyl methacrylate, sodium salt of a monoester of a higher alcohol of maleic acid, sodium acrylamidostearate, polyethylene glycol monoallylate Le, methoxy polyethylene glycol (meth) acrylate, phenoxy polyethylene glycol (meth) acrylate, methoxyethyl (meth)
Acrylate, butoxyethyl (meth) acrylate,
Examples include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, acrylamide, vinylpyrrolidone, and the like.

When the proportion of these hydrophilic monomers in the copolymer resin is less than 1% by weight of the total monomers, the water solubility of the obtained copolymer resin becomes insufficient, and when it exceeds 50% by weight. In addition, the drying property is insufficient, the film becomes hard and the effect of improving curl is reduced. Therefore, it is necessary to copolymerize these hydrophilic monomers in the range of 1 to 50% by weight, more preferably 1 to 40% by weight.

In addition, among these hydrophilic monomers, especially ethylenic monomers such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, fumaric acid, monoalkylmaleic acid, monoalkylitaconic acid, monoalkylfumaric acid, etc. Saturated carboxylic acid-containing monomers are preferably used.

On the other hand, as the alkyl ester monomer of (meth) acrylic acid constituting the copolymer resin used in the present invention, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, Butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, (meth)
And stearyl acrylate.

The proportion of these (meth) acrylic acid alkyl ester monomers in the copolymer resin is 20 to 99% of all monomers.
It is adjusted in the range of weight%.

In the present invention, among these alkyl ester monomers of (meth) acrylic acid, in particular, butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, (meth) acrylic acid-2 (Meth) acrylic acid ester monomers having a _C4-10 alkyl group such as _-ethylhexyl are preferably used.

Further, other monomers copolymerizable with the above-mentioned monomers constituting the copolymer resin used in the present invention include, for example, vinyl acetate, vinyl chloride, vinylidene chloride, (meth) acrylonitrile, styrene, Ethylene, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, 1,3- Butylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethanetetra (meth) acrylate, divinylbenzene, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) ) Acrylate, Glycidyl (meth) acrylate, methyl glycidyl (meth) acrylate,
N-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N, N'-methylenebis (meth) acrylamide and the like can be mentioned.

The proportion of these other copolymerizable monomers in the copolymer resin is adjusted in the range of 0 to 40% by weight of the total monomers.

In particular, in the release sheet of the present invention, 2 to 40% by weight of the hydrophilic monomer as described above, 50 to 90% by weight of a (meth) acrylate monomer having a C4 to _C10 alkyl group, ) Other monomers 0-40, such as acrylonitrile
A copolymer resin obtained by copolymerizing by weight% is most preferably used.

The copolymer resin of the present invention is produced by a method of emulsion-copolymerizing or graft-copolymerizing each of the above monomers in an aqueous system in the presence of an emulsifier (protective colloid), a chain transfer agent, a polymerization initiator, and the like. The amount of the emulsifier used is particularly important, and it is contained in the range of 2 to 10% by weight based on the total amount of the monomers constituting the copolymer resin.

Examples of the emulsifier include anionic emulsifiers such as sodium dodecylbenzenesulfonate and sulfate of alkaryl polyether; and nonionic emulsifiers such as polyoxyethylene nonylphenol ether and polyoxyethylene / polyoxypropylene block copolymer. A cationic emulsifier such as laurylpyridinium chloride, cetyltrimethylammonium bromide, etc .; polyvinyl having at least one functional group selected from polyvinyl alcohol, (meth) acryloyl group, haloalkyl (meth) acryloyl group, and N-methylolacrylamide group. Examples include protective colloids such as alcohols, polyacrylamides, polyethylene glycol derivatives, and casein.

Examples of the chain transfer agent include thioglycerol, ethylene thioglycol, thioglycolic acid, and n-glycol.
Examples of the polymerization initiator include, for example, hydrogen peroxide, potassium persulfate, ammonium persulfate, and a so-called redox-based polymerization initiator comprising a combination thereof with a reducing agent such as sodium sulfite and sodium acid sulfite. Is mentioned.

When the content of the emulsifier is less than 2% by weight, the stability of the obtained emulsion becomes insufficient, and the particle size of the polymer becomes large. If it is contained in such a large amount as to exceed 10% by weight, the adhesion between the undercoat layer and the release agent layer is reduced. On the other hand, if the glass transition temperature of the copolymer resin is lower than −60 ° C., the adhesiveness of the film becomes too strong, and if it is higher than 20 ° C., the obtained film becomes too hard and loses practicality.

Further, it is desirable to use a release substrate having a strength of 1.0 g / cm ³ or less. With those in the release substrate bulk density 1.0 g / cm ³ or more, such as glassine paper, since the uneven moisture occurs after the thermal fixation of the toner in Kanji printer,
The toner is liable to generate unevenness, curl, and the like, and hardly dissipates heat, so that toner blocking is likely to occur.

The stiffness of the release substrate is closely related to the folding operation of the pressure-sensitive adhesive sheet in the automatic folding stacker. Therefore, in order to obtain good stacker suitability, the stiffness of the release substrate is measured between 70 and 200 mg (measured with a Gurley stiffness tester, see Paper Trade Journal, 104 , p. 28).
7 to 290 (1937)). Such an embodiment is one of preferred embodiments of the present invention. When the stiffness of the peeled substrate is smaller than 70 mg, folding occurs at places other than the horizontal perforations, and when the stiffness is larger than 200 mg, it may not be folded at the horizontal perforations, which deteriorates the suitability of the stacker. is there.

The adhesive strength between the surface substrate and the release substrate is closely related to the suitability for labeling in a kanji printer, and in order to obtain good release performance, the tensile strength of the release agent (JIS K-6
301) is preferably 30 kg / cm ² or more. If the tensile strength of the release agent is less than 30 kg / cm ² , the adhesive label will fall off inside the printer, resulting in poor running of the paper.

In kanji printers, to improve the toner fixability, the surface of the surface substrate should have a glass transition temperature of -40 to 40.
It is desirable to apply or impregnate the polymer at 0 ° C. Such polymers include ethylene resin, propylene resin, styrene resin, birni chloride resin, vinylidene chloride resin, ethylene-vinyl acetate copolymer resin, ethylene
Vinyl chloride copolymer resin, vinyl chloride / vinyl acetate copolymer resin, ethylene / acrylate copolymer resin, ethylene / methacrylate copolymer resin, amide resin, nitrile resin, urethane resin, acrylate ester A water-dispersible or water-soluble polymer such as a coalescing resin or a copolymer resin, a methacrylic acid ester polymer resin or a copolymer resin, and the like can be given.

Among them, ethylene-vinyl acetate copolymer resin, ethylene-vinyl chloride copolymer resin, vinyl chloride-vinyl acetate copolymer resin, acrylate polymer resin or copolymer resin, methacrylate polymer resin or Copolymer resins are preferably used because of their excellent effects.

When the glass transition temperature of the above-mentioned polymer is lower than -40 ° C, there is a problem that the tackiness of the film becomes too strong and blocking occurs. On the other hand, if the glass transition temperature is higher than 100 ° C., the resulting film becomes too hard, causing curling on the surface to which the processing liquid is applied, resulting in poor fixability of the toner.

Incidentally, the method for producing the polymer is not particularly limited, for example, in water or a solvent, a chain transfer agent,
It is produced by a method of solution polymerization in the presence of a polymerization initiator or the like, or a method of emulsion polymerization in an aqueous system in the presence of a chain transfer agent, a polymerization initiator, an emulsifier (dispersant) or the like.

Further, the processing solution containing the specific polymer is desirably prepared as a water-dispersible processing solution in view of the drying property of the processing solution, the effect of improving the fixability of the toner, the effect of curl correction, and the safety of coating. .

In the polymer as described above, for example, cellulose derivatives such as methylcellulose, ethylcellulose, hydroxyethylcellulose, carboxymethylcellulose, dextrin, acid-treated starch, oxidized starch, crosslinked starch, starch ester, as long as the desired effects of the present invention are not impaired, Various water-soluble polymers such as starch derivatives such as graft copolymerized starch; water-soluble polymers such as polyhydric alcohols such as ethylene glycol, glycerin, trimethylolpropane, and diethylene glycol; and polyalkylene glycols such as polyethylene glycol and polypropylene glycol. Plasticizer; defoamer;
A wetting agent; a lubricant; a leveling agent; a curing agent; a thickening agent;

The treatment liquid is prepared by adding various additives to the above-mentioned specific polymer as a main component, and the concentration of the treatment liquid is in the range of 1 to 50% by weight, preferably 2 to 20% by weight. It is desirable to prepare it so that

The method of applying or impregnating the treatment liquid thus prepared on the surface of the surface substrate is not particularly limited. For example, various devices such as an air knife coater, a roll coater, a gravure coater, a bar coater, a blade coater, and a size press coater. Is appropriately used.

The amount of application or impregnation is preferably adjusted in the range of about 0.05 to 20 g / m ² by dry weight, and particularly about 0.1 to 8 g / cm ² is desirably used.

There is no particular limitation on the method of forming the pressure-sensitive adhesive sheet, and, for example, a solvent-based pressure-sensitive adhesive is applied to a release sheet obtained by providing a primer layer on a release substrate and applying a release agent on the primer layer according to a conventional method. An adhesive, an emulsion-type pressure-sensitive adhesive, a hot-melt-type pressure-sensitive adhesive, and the like are applied, dried if necessary, and the surface substrate is bonded to perform humidity control and the like to finish the pressure-sensitive adhesive sheet.

"Examples" Hereinafter, the present invention will be described more specifically with reference to Examples, but of course, the present invention is not limited thereto. In the examples, the coating amount, the number of copies, the mixing ratio, and the like are all represented by solid contents.

Example 1 A treatment solution having the following composition was applied to the surface of a high-quality paper having a basis weight of 64 g / m ² and a thickness of 75 μm using an air knife coater so that the dry coating amount was 1.0 g / m ^2, and the coating was performed at 90 ° C. for 30 seconds. It was dried and smoothed with a super calender to obtain a surface substrate.

Treatment liquid composition Acrylic ester copolymer resin (glass transition temperature 47
℃, trade name: Ricabond ES-20, manufactured by Chuo Rika Kogyo) 97
An aqueous coating solution (concentration: 8% by weight) containing 1 part by weight of a wax emulsion and 2 parts by weight of a defoamer was prepared.

Production of release sheet butyl acrylate 270 g, acrylic acid 15 g, acrylonitrile 113 g, N-methylol acrylamide 2 g, polyoxyethylene nonylphenol ether emulsifier 5 g,
An emulsified monomer mixture (I) comprising 5 g of an oxyethylene / oxypropylene block polymer emulsifier and 170 g of ion-exchanged water was prepared.

Next, a stirrer, cooler, dropping funnel, nitrogen suction pipe,
In a two four-necked flask equipped with a thermometer, 2 g of a 1: 1 mixture of 240 g of ion-exchanged water, a polyoxyethylene nonylphenol ether emulsifier and an oxyethylene / oxypropylene block polymer emulsifier, and 0.8 g of potassium persulfate
After the temperature was raised to 70 ° C. while replacing with nitrogen, 1/6 of the emulsified monomer mixture (I) was added dropwise.

When the reaction rate reached 90%, the remaining emulsified monomer mixture (I) was added dropwise over 2 hours to polymerize. After completion of the dropwise addition, the mixture was aged at 70 ° C. for 2 hours to complete the reaction. After completion of the aging, the contents of the flask were cooled to 40 ° C., and a neutralization reaction was performed by adding an aqueous sodium hydroxide solution. After the completion of the reaction, the mixture was vigorously stirred to obtain a water-dispersible copolymer used in the present invention. (Content of emulsifier: 2.9% by weight) The glass transition temperature of the obtained water-dispersible copolymer was -29 ° C.

To 75 parts by weight of this water-dispersible copolymer, 24 parts by weight of an aqueous solution of oxidized starch (trade name: Ace C. Oji Corn Starch) was added, and further, colloidal silica (trade name: Snowtex 30, Nissan Chemical Industries, Ltd.) Was added to prepare an aqueous coating solution (II) for an undercoat layer having a concentration of 30% by weight.

The above-mentioned aqueous coating liquid for undercoat layer (II) was applied to a high-quality paper (peeling substrate) having a basis weight of 64 g / m ² and a thickness of 75 μm using a bar coater so that the dry coating amount was 4 g / m ^2, and then 120 ° C. And dry for 1 minute
A smoothing treatment was performed with a super calender to obtain a peeled substrate.
(Tensity: 0.82 g / cm ³ , Stiffness: 90 mg) On this undercoat layer, a silicone release agent (trade name: BY24
-162, manufactured by Toray Silicone Co., Ltd.) was applied with a bar coater so that the dry coating amount was 1.0 g / m ^2, and dried at 130 ° C. for 1 minute to obtain a release sheet. (Tensile strength of release agent: 40 kg / cm ² ) Production of pressure-sensitive adhesive sheet An acrylic emulsion pressure-sensitive adhesive (trade name: Nicazole TS-662, manufactured by Nippon Carbide Co., Ltd.) is applied to the release-coated surface of this release sheet by a reverse roll coater. With a dry coating weight of 20
g / m ² and dried at 120 ° C. for 1 minute. Next, the surface substrate was overlaid on the pressure-sensitive adhesive layer and bonded by a press roll, and then the pressure-sensitive adhesive sheet was obtained by controlling the humidity of the release sheet to 6%.

The obtained adhesive sheet is a kanji printer (trade name: MEL
COM 8270, manufactured by Mitsubishi Electric Corporation).

Example 2 A treatment solution having the following composition was applied on a surface of a high-quality paper having a basis weight of 64 g / m ² and a thickness of 75 μm with a bar coater so that the dry coating amount was 1.2 g / m ^2, and was then applied at 100 ° C. for 30 seconds. It was dried and smoothed with a super calender to obtain a surface substrate.

Treatment liquid composition Ethylene / vinyl acetate copolymer resin (glass transition temperature 0 ° C, trade name: Ricabond BE-800, manufactured by Chuo Rika Kogyo Co., Ltd.)
An aqueous coating solution (concentration: 10% by weight) containing 90 parts by weight, 8 parts by weight of colloidal silica, and 2 parts by weight of an antifoaming agent was prepared.

Production of release sheet 190 g of 2-ethylhexyl acrylate, 60 g of methyl methacrylate, 120 g of acrylonitrile, 30 g of acrylic acid,
Polyoxyethylene alkyl phenyl sulfate emulsifier 8
g, 8 g of sodium dioctyl sulfosuccinate emulsifier,
An emulsified monomer mixture (I) comprising 170 g of ion-exchanged water was prepared.

Polymerization was carried out in the same manner as in Example 1 except that the obtained emulsion monomer mixture (I) was used, and the mixture was aged at 70 ° C. for 2 hours to complete the reaction.

After completion of aging, the contents of the flask were cooled to 50 ° C., a neutralization reaction was performed by adding an aqueous solution of potassium hydroxide, and after completion of the reaction, the mixture was vigorously stirred to obtain a water-soluble copolymer [A] used in the present invention. Was. (Emulsifier content: 3.8% by weight) The glass transition temperature of the obtained water-soluble copolymer [A] was -6 ° C.

Next, 100 g of butyl acrylate, 250 g of methyl methacrylate, 50 g of acrylic acid, 5 g of a polyoxyethylene nonylphenol ether emulsifier, 5 g of an oxyethylene / oxypropylene block polymer emulsifier, and ion-exchanged water
An emulsion monomer mixture (II) consisting of 170 g was prepared and polymerized and aged in the same manner as in Example 1 below.

After completion of aging, the contents of the flask were cooled to 50 ° C., a neutralization reaction was performed by adding an aqueous solution of potassium hydroxide, and after completion of the reaction, vigorous stirring was performed to obtain a water-soluble copolymer [B] used in the present invention. Was. The glass transition temperature of the obtained water-soluble copolymer [B] was 42 ° C.

30 parts by weight of the water-soluble copolymer [B] was added to 70 parts by weight of the water-soluble copolymer [A] to prepare an aqueous coating liquid for an undercoat layer having a concentration of 35% by weight.

On a high quality paper having a basis weight of 84 g / m ² and a thickness of 90 μm, the above-mentioned aqueous coating solution for the undercoat layer was dried with a blade coater to a coating amount of 3.5 g / m ^2.
, Dried at 120 ° C for 1 minute, and smoothed with a super calender to obtain a peeled substrate. (Tension:
0.85 g / cm ² , rigidity: 120 mg) On this undercoat layer, a silicone release agent (trade name: X-62)
-2402, manufactured by Shin-Etsu Chemical Co., Ltd.) was applied with a gravure coater so that the dry coating amount was 0.9 g / m ^2, and dried at 130 ° C. for 1 minute to obtain a release sheet. (Tensile strength of release agent: 35 kg / cm ² ) Manufacture of pressure-sensitive adhesive sheet An acrylic emulsion pressure-sensitive adhesive (trade name: Cybinol AT-560, manufactured by Siden Chemical Co., Ltd.) was applied to the release-coated surface of this release sheet using a comma coater ( (Hirano Techseed)
In dry coating amount was applied so as to 18g / m ^2, 90 at 100 ° C.
Dried for seconds.

Next, the surface substrate was overlaid on the pressure-sensitive adhesive layer and bonded by a press roll, and then the pressure-sensitive adhesive sheet was obtained by controlling the humidity of the release sheet to 6%.

The obtained adhesive sheet is a kanji printer (trade name: MEL
(C0M 8270, manufactured by Mitsubishi Electric Corporation).

Example 3 A treatment liquid having the following composition was applied on a surface of a high-quality paper having a basis weight of 52 g / m ² and a thickness of 90 μm with a bar coater so that the dry coating amount was 0.8 g / m ^2, and the coating was performed at 80 ° C. for 30 seconds. It was dried and smoothed with a super calender to obtain a surface substrate.

Treatment liquid composition Acrylic ester copolymer resin (glass transition temperature 70
° C, trade name: Licabond SA-Z713, manufactured by Chuo Rika Kogyo) 9
An aqueous coating liquid (concentration: 12% by weight) containing 6 parts by weight, 3 parts by weight of a wax emulsion, and 1 part by weight of an antifoaming agent was prepared.

Manufacture of release sheet 300 g of 2-ethylhexyl acrylate, 20 acrylic acid
g, 78 g of methyl methacrylate, 2 g of polyethylene glycol dimethacrylate, 10 g of a polyoxyethylene alkylphenyl sulfate-based emulsifier, 10 g of a sodium dioctylsulfosuccinate-based emulsifier, and 170 g of ion-exchanged water to prepare an emulsified monomer mixture (I).

Polymerization was carried out in the same manner as in Example 1 except that the obtained emulsion monomer mixture (I) was used, and the mixture was aged at 70 ° C. for 2 hours to complete the reaction. The glass transition temperature of this copolymer is -28 ° C
Met.

Next, butyl acrylate 25 g, acrylonitrile 60
g, 15 g of acrylic acid, 3 g of a polyoxyethylene alkylphenyl sulfate-based emulsifier, 0.2 g of ammonium persulfate, and 100 g of ion-exchanged water to prepare an emulsion monomer mixture (II).

During the previously polymerized copolymerization, the above-mentioned emulsified monomer mixture (II) was added dropwise over 1 hour while maintaining the temperature in the flask at 70 ° C., and the mixture was allowed to react for 3 hours. A polymer was obtained. An aqueous solution of potassium hydroxide was added thereto to carry out a neutralization reaction, followed by vigorous stirring to obtain a water-soluble graft copolymer. The average particle size of the obtained water-soluble graft copolymer is 0.1.
μm. (Emulsifier content: 5.2% by weight) To 90 parts by weight of this water-soluble copolymer, 8 parts by weight of polyethylene glycol and 2 parts by weight of colloidal silica (trade name: Snowtex 30, manufactured by Nissan Chemical Industries, Ltd.) were added. Concentration 33
By weight, an aqueous coating liquid for an undercoat layer was prepared.

On a high quality paper having a basis weight of 97 g / m ² and a thickness of 125 μm, apply the following undercoat layer aqueous coating solution with a bar coater so that the dry coating amount is 4.0 g / m ^2, and dry at 120 ° C. for 1 minute. A smoothing treatment was performed with a super calender to obtain a peeled substrate. (Tension: 0.85g
/ cm ³ , rigidity: 150mg) On this undercoat layer, a silicone release agent (trade name: SD-7)
320, a 9% toluene solution of Toray Silicone Co.) was applied by a bar coater so that the dry coating amount was 1.0 g / m ^2, and dried at 140 ° C. for 1 minute to obtain a release sheet. (Tensile strength of release agent: 45 kg / cm ² ) Manufacture of pressure-sensitive adhesive sheet An acrylic emulsion pressure-sensitive adhesive (trade name: Oribain BPW-3110, manufactured by Toyo Ink Mfg. Co., Ltd.) is slotted on the release-coated surface of this release sheet. Coating was performed with a die coater so that the dry coating amount was 20 g / m ^2, and the coating was dried at 120 ° C. for 1 minute.

Next, the surface substrate was overlaid on the pressure-sensitive adhesive layer and bonded by a press roll, and then the pressure-sensitive adhesive sheet was obtained by controlling the humidity of the release sheet to 6%.

The obtained adhesive sheet is a kanji printer (trade name: MEL
(C0M 8270, manufactured by Mitsubishi Electric Corporation).

Example 4 An adhesive sheet was produced in the same manner as in Example 3 except that high quality paper having a basis weight of 52 g / m ² and a thickness of 70 μm was used as a surface substrate.

The obtained adhesive sheet is used as a kanji printer (trade name: MEL
C0M 8270 (manufactured by Mitsubishi Electric Corporation) showed that the paper-feeding suitability was good, but the toner fixability was insufficient.

Example 5 Basis weight 120 g / m ² , thickness 160 μm (tension: 0.75 g / cm ³ , rigidity: 2
A release sheet was obtained in the same manner as in Example 1 except that high-quality paper (30 mg) was used.

An adhesive sheet was obtained on this release sheet in the same manner as in Example 1.

The obtained adhesive sheet is used as a kanji printer (trade name: MEL
(COM 8270, manufactured by Mitsubishi Electric Corp.), the toner had good fixability, but occasionally jammed the sheet.

Comparative Example 1 Production of Release Sheet Basis weight 85 g / m ² , thickness 75 μm (tension: 1.13 g / cm ³ , rigidity: 210 m)
g) 9% of the same silicone release agent (trade name: BY24-162, manufactured by Toray Silicone Co., Ltd.) on the glassine paper of Example 1
The toluene solution was applied by a gravure coater so that the dry coating amount was 1.0 g / m ^2, and dried at 130 ° C. for 1 minute to obtain a release sheet.

Production of pressure-sensitive adhesive sheet The same acrylic emulsion pressure-sensitive adhesive as in Example 1 (trade name: Nicazole TS-66) was applied to the release-coated surface of this release sheet.
2, manufactured by Nippon Carbide Co.) was applied by a reverse roll coater so that the dry coating amount was 200 g / m ² , and dried at 120 ° C. for 1 minute. Next, the same surface substrate as in Example 1 was overlaid on the pressure-sensitive adhesive layer and bonded with a press roll, and then the pressure-sensitive adhesive sheet was obtained by controlling the humidity of the release sheet to 6%.

The obtained adhesive sheet was converted to a kanji printer (trade name: MELCO
(M8270, manufactured by Mitsubishi Electric Corporation). When printing was performed, jamming occurred, after toner was fixed by heat, blocking occurred, and uneven moisture absorption caused unevenness, resulting in poor paper passing aptitude.

Comparative Example 2 Silicone release agent (trade name: SRX-211, manufactured by Toray Silicone Co., Ltd.) as a release agent (tensile strength of adhesive: 15 kg / c)
except using m ²⁾ in the same manner as in Example 1 to obtain an adhesive sheet.

This adhesive sheet can be used with a kanji printer (product name: MELCOM
8270, manufactured by Mitsubishi Electric Corporation), the label peeling force was too small, the label fell off in the printer, and smooth paper passing was not possible.

[Effect] The pressure-sensitive adhesive sheet of the present invention was excellent in stacking suitability, label peeling suitability, toner fixing property and the like.

Claims (4)

(57) [Claims] 1. A pressure-sensitive adhesive sheet comprising at least an undercoat layer, a release layer, a pressure-sensitive adhesive layer and a surface substrate laminated on a release substrate, wherein the main component of the undercoat layer is 2 to 10% by weight of an emulsifier.
Contains an aqueous acrylate copolymer resin having a glass transition temperature of −60 to 20 ° C., and a release substrate having a tension of 1.0 g.
/ cm ³ or less. 2. The stiffness of a release substrate (Paper Trade
Journal. 104 , pp. 287-290 (1937), Gurley stiffness tester) is 70-200 mg. 3. The release agent has a tensile strength (JIS K-6301) of 30K.
The pressure-sensitive adhesive sheet according to claim 1, wherein the pressure-sensitive adhesive sheet has a g / cm ² or more. 4. A glass substrate having a glass transition temperature of -40 to 10 on the surface of a surface substrate.
The method according to claim 1, wherein a treatment liquid containing a polymer at 0 ° C. as a main component is applied or impregnated.
The pressure-sensitive adhesive sheet according to (2) or (3).