JPH10104867A - Adhesive sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an adhesive sheet without causing jamming when it is passed through a copying machine or a printer adopting an electrophotographic transfer system by forming recording paper with a toner transfer layer having satisfactory toner fixability and sticking a peeling sheet to the rear side of the recording paper through an adhesive layer. SOLUTION: This adhesive sheet has a toner transfer layer on one side of the base sheet and a peeling sheet stuck to the other side though an adhesive layer. The toner transfer layer is an acrylic resin layer contg. fine particles of an acrylic ester polymer as a filler which does not form any film and the coefft. of kinetic friction on the surface of the toner transfer layer is in the range of 0.120-0.160.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive sheet suitable for recording by a copying machine or a printer of an electrophotographic transfer system, that is, for performing recording comprising a transfer layer of powder toner.

[0002]

2. Description of the Related Art Recording with an electrophotographic transfer type copying machine or printer is performed by developing an electrostatic latent image formed on an insulative photosensitive member having a drum shape by a powder toner developing method. It consists of a system for transferring images to recording paper.

As a recording paper for forming a recording by this system, that is, a recording paper for forming a transfer layer using powder toner, ordinary high quality paper can be used without providing a special toner transfer layer. Is the feature.

However, in order to obtain a clearer recorded image, that is, to enhance the fixability of the powder toner, an acrylic resin of the same type as the acrylic resin used for the binder of the powder toner is used. Paper having a toner transfer layer formed of a film-forming substance obtained by using a binder resin and appropriately adding a pigment and other auxiliaries to the binder resin.

[0005]

By the way, as a pressure-sensitive adhesive sheet in which a release sheet is adhered to the back surface of a recording paper via a pressure-sensitive adhesive layer, recording by a copying machine or a printer by the above-described electrophotographic transfer method is performed. Adhesive sheets that can be used are widely used as label sheets.In this kind of adhesive sheet, an adhesive sheet obtained by attaching a release sheet to the back surface of a recording paper having the toner transfer layer via an adhesive layer is When this is passed through a copying machine or printer using an electrophotographic transfer system, a paper passing failure often occurs.

That is, in a normal electrophotographic transfer type copier or printer, one sheet of recording paper stacked in a paper feed cassette is fed by a paper feed roller and a separation pad provided opposite to the paper feed roller. Each of which is separated and fed to a transfer section of a visualized image. The friction between the surface of the separation pad and the surface of the recording paper which comes into contact with the surface of the separation pad causes the inside of the paper feed cassette to be separated. It is possible to accurately feed the recording paper one by one, but in the case of the recording paper having the toner transfer layer, the recording paper stops before reaching the transfer section of the visible image, A paper feeding failure that prevents accurate paper feeding occurs.

When the recording paper having the toner transfer layer is passed through a copying machine or a printer of an electrophotographic transfer system, the above-mentioned paper passing failure is caused by attaching a release sheet to the back surface of the recording paper via an adhesive layer. When a pressure-sensitive adhesive sheet is formed, the problem occurs more frequently as the weight of the sheet increases.

The present inventor has clarified that the cause of the paper passing failure frequently occurring in the pressure-sensitive adhesive sheet having the toner transfer layer is as described below, and has completed the present invention.

That is, the kinetic friction coefficient of the toner transfer layer of the recording paper having the toner transfer layer is much larger than the kinetic friction coefficient of the recording paper having no toner transfer layer. When the adhesive sheet is fed from inside the paper feed cassette so as to be in contact with the surface of the separation pad of an electrophotographic transfer type copying machine or printer, the gap between the toner transfer layer of the adhesive sheet and the surface of the separation pad is extremely low. Due to the occurrence of large friction and the increase of the self-weight of the pressure-sensitive adhesive sheet itself, the pressure-sensitive adhesive sheet stops before reaching the transfer section of the visualized image, thereby causing a paper passing failure.

Accordingly, an object of the present invention is to provide an adhesive sheet comprising a recording sheet having a toner transfer layer and a release sheet adhered to the back surface of the recording sheet via an adhesive layer, so that it can be passed through an electrophotographic transfer type copier or printer. An object of the present invention is to provide a pressure-sensitive adhesive sheet that does not cause paper passing failure.

[0011]

The above object is achieved by the pressure-sensitive adhesive sheet of the present invention having the following constitution. That is, the present invention is an adhesive sheet having a toner transfer layer on one surface of a base sheet, and a release sheet adhered to the other surface of the base sheet via an adhesive layer, wherein the toner The transfer layer is formed of an acrylic resin layer containing non-film-forming acrylic ester polymer fine particles as a filler, and the coefficient of kinetic friction of the surface of the toner transfer layer is from 0.120 to
It consists of an adhesive sheet in the range of 0.160.

In the pressure-sensitive adhesive sheet of the present invention having the above structure, the coefficient of dynamic friction of the surface of the toner transfer layer is 0.140.
More preferably, it is within the range of 0.150.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The pressure-sensitive adhesive sheet of the present invention comprises a substrate sheet, a toner transfer layer formed on one surface of the substrate sheet, and a pressure-sensitive adhesive layer on the other surface of the substrate sheet. It is a laminated sheet composed of a release sheet and a release sheet adhered to the sheet.

The toner transfer layer is composed of an acrylic resin layer containing non-film-forming acrylate polymer fine particles as a filler, and the surface of the toner transfer layer has a dynamic friction coefficient of 0.120 to 0.1. 160. In addition, paper-passing properties for registration rolls in copiers and printers,
In consideration of the surface condition of the pressure-sensitive adhesive sheet, the coefficient of kinetic friction of the surface of the toner transfer layer is preferably in the range of 0.140 to 0.150.

In the pressure-sensitive adhesive sheet of the present invention having the above-mentioned structure, as the base sheet, high-quality paper, medium-quality paper, coated paper, art paper, kraft paper, glazed paper, or the like is used.

As described above, the toner transfer layer is composed of an acrylic resin layer containing a non-film-forming acrylate polymer fine particle as a filler, and an acrylic resin emulsion which functions as a binder and a non-film-forming acrylic resin emulsion. It can be formed as a coating layer of a coating agent comprising a mixture with an acrylic acid ester polymer fine particle emulsion.

Examples of the acrylic resin which functions as a binder include, for example, methyl acrylate polymer, ethyl acrylate polymer, butyl acrylate polymer, acrylic acid 2-acrylate.
Ethylhexyl polymer, methyl methacrylate polymer, ethyl methacrylate polymer, butyl methacrylate polymer,
A cyclohexyl methacrylate polymer, a stearyl methacrylate polymer, or the like can be used.

The non-film-forming acrylic acid ester polymer fine particles have heat resistance due to internal crosslinking.
The state of the fine particles does not collapse even when the coating layer containing the coating agent is heated when drying the coating layer or when heated by a copying machine or a printer.

If the particle size of the non-film-forming acrylic acid ester polymer fine particles is too large or too small, the kinetic friction coefficient of the surface of the toner transfer layer is set to 0.120 to 0.160. You will not be able to do it. That is, if the particle size is too large, the coefficient of kinetic friction on the surface of the toner transfer layer cannot be made 0.120 or more, and the transferability of the toner transfer layer deteriorates. If the particle size is too small, a large amount of the fine particles must be added, which is uneconomical. Further, the effect of adding the fine particles cannot be obtained, and the dynamic friction coefficient of the surface of the toner transfer layer is reduced to 0.1.
160 or less. For this reason, the non-film-forming acrylate polymer fine particles preferably have an average particle size of about 0.1 to 20.0 μm,
Those having a thickness of about 0.5 to 10.0 μm are more preferable.

The toner transfer layer composed of an acrylic resin serving as a binder and non-film-forming acrylate polymer fine particles has a thickness of 100% by weight of the acrylic resin (solid component) serving as a binder. 0.5 to 5.0 (dry) g / m ^{2 by} about 10 to 15% by weight of a water-based coating agent containing 15 to 40 parts by weight of solid acrylic acid ester polymer fine particles (solids). ,
More preferably, it is formed to about 1.0 to 3.0 (dry) g / m ² .

It is convenient to previously form the toner transfer layer on one surface of the base sheet with the above-mentioned coating agent, but a release sheet is formed on the other surface of the base sheet via an adhesive layer. After sticking, a toner transfer layer may be formed on one surface of the base sheet.

The application of the coating agent for forming the toner transfer layer can be performed by a usual application method such as an air knife coater, a roll coater, a gravure coater, a bar coater and the like.

The pressure-sensitive adhesive layer laminated on the other side of the base sheet is coated with a water-based or solvent-based general pressure-sensitive adhesive, that is, an adhesive such as a natural rubber, a synthetic rubber, or an acrylic ester polymer. It is formed as a coating layer of an agent.

The release sheet adhered via the pressure-sensitive adhesive layer is a sheet having a release surface, such as high quality paper, medium quality paper, coated paper, art paper, kraft paper, glazed paper, etc. A paper obtained by subjecting a base paper to a release agent treatment with silicone or the like is used. In addition, this release sheet
It is a matter of course that the release sheet is attached so that the release surface of the release sheet is in contact with the pressure-sensitive adhesive layer.

The base paper used to obtain the release sheet is formed by forming a sealing layer on the base paper before subjecting the base paper to a release agent treatment with silicone or the like. It is preferable to prevent penetration of the agent. For example, those using a release sheet formed by attaching a plastic film to form the above-mentioned sealing layer are pressure-sensitive adhesive sheets applicable to printers without a heating step, but include kaolin, aluminum hydroxide, and carbonate. A release sheet formed with a filler layer formed of a coating layer of a filler such as calcium and an aqueous binder such as styrene-butadiene copolymer, casein, carboxymethylcellulose, and PVA was used. This is an adhesive sheet that can be applied to a heat fixing type copying machine or printer.

As described above, when recording is performed on a conventional adhesive sheet having a toner transfer layer by a copying machine or a printer of an electrophotographic transfer system, as described above, the paper passing failure is caused by the toner on the recording surface of the adhesive sheet. This is caused by too much friction between the transfer layer and the surface of the separation pad.In general, double feed due to too large a friction coefficient between the front and back surfaces of the pressure-sensitive adhesive sheet is also caused by the electrophotographic transfer method. When recording on an adhesive sheet by a copying machine or a printer, it causes paper passing failure.

On the other hand, in the above-mentioned pressure-sensitive adhesive sheet of the present invention, the kinetic friction coefficient of the toner transfer layer is lower than that of the conventional toner transfer layer. By forming the paper with plain paper, the coefficient of friction between the back surface of the pressure-sensitive adhesive sheet, which is a release sheet, and the surface of the pressure-sensitive adhesive sheet, which is a toner transfer layer, does not become too large. I have.

Furthermore, the fact that the coefficient of friction between the surface of the pressure-sensitive adhesive sheet and the resist roll and the coefficient of friction between the back surface of the pressure-sensitive adhesive sheet and the resist roll are too small may be reduced by the use of an electrophotographic transfer type copier or printer. However, in the pressure-sensitive adhesive sheet of the present invention, the kinetic friction coefficient of the toner transfer layer is the same as or close to the kinetic friction coefficient of plain paper. By using plain paper as the base paper in the release sheet forming the back surface, it is possible to prevent the friction coefficient between the pressure-sensitive adhesive sheet surface and the resist roll, and the friction coefficient between the pressure-sensitive adhesive sheet back surface and the resist roll from becoming too small. .

Therefore, in the pressure-sensitive adhesive sheet of the present invention,
It is preferable that the base paper in the release sheet forming the back surface of the pressure-sensitive adhesive sheet is formed of plain paper so as to avoid poor paper passing due to the above-described causes.

In addition, when a recording image is formed on an adhesive sheet by an electrophotographic transfer type copying machine or printer, paper passing failure may be caused by an adhesive sticking out from an end face around the adhesive sheet to a roll or the like. Is also caused by curl or the like generated in the adhesive sheet itself.

Therefore, in the pressure-sensitive adhesive sheet of the present invention,
The pressure-sensitive adhesive layer is formed of a cross-linkable pressure-sensitive adhesive having a high cohesive force, thereby preventing the pressure-sensitive adhesive from protruding from the peripheral end surface of the pressure-sensitive adhesive sheet, and preventing toner stains and the like due to the adhesion of the protruded pressure-sensitive adhesive. Is preferred.

Further, both the base sheet for forming the toner transfer layer and the base paper on which the release agent treatment is performed to form a release sheet are made of substantially the same material, so that moisture absorption, heating and the like are performed. It is preferable to suppress curl generated in the pressure-sensitive adhesive sheet.

[0033]

EXAMPLES Hereinafter, the specific constitution of the pressure-sensitive adhesive sheet of the present invention will be described based on examples, and the results of tests on the physical properties of the pressure-sensitive adhesive sheet will be described.

Examples 1-2 and Comparative Examples 1-6 Production of Release Sheets A base paper made of high quality paper "Shin Oji Paper Co., Ltd .: Sunflower" having a basis weight of 52.3 g / m ² was coated on one side with a polyvinyl alcohol aqueous solution. Is applied and dried to form a sealing layer, and a silicone resin “Toray Silicone Co., Ltd .:
3% by weight of a silicone-based release agent based on a mixed resin of 0.6% by weight of silicone resin "Toray Silicone Co., Ltd .: SRX-212" as well as 100 parts by weight of "SRX-211"
1 g (dry) / m of the toluene solution was measured with a bar coater.
After coating on No. ² , this was dried in an oven at 120 ° C. for 2 minutes to obtain a release sheet having a release agent layer.

Production of a Base Sheet Having a Toner Transfer Layer A base sheet made of high-quality paper "Shin Oji Paper Co., Ltd .: Sunflower" having a basis weight of 52.3 g / m ² was coated on one surface with the following solid components: A water-based coating agent having a mixing ratio of parts by weight shown in the predetermined column of Table 1] was applied at 1.5 g (dry) / m ² ,
By drying, a base sheet having a toner transfer layer was obtained.

The julimer is an aqueous emulsion of an acrylic ester copolymer "Nippon Pure Chemical Co., Ltd .: julimar SEK-301", which is an emulsion of an acrylic resin which performs a binder function.

PG-2 is an aqueous emulsion of non-film-forming acrylate polymer fine particles having an average particle size of 3.0 μm (Siden Chemical Co., Ltd .: matting agent PG-2). 7-30 is zinc stearate powder "Chukyo Oil &Fat"
Co., Ltd .: Hydrin Z-7-30 ".

Further, each coating agent was used after adjusting to an aqueous dispersion of 10.0% by weight of a solid component in the coating agent.

[0039]

[Table 1]

Manufacture of pressure-sensitive adhesive sheet An acrylic pressure-sensitive adhesive "Nippon Carbide Co., Ltd .: Nicazole TS-507" is applied to the release layer surface of the release sheet.
With a reverse roll coater at 1.5 g (dry) /
m ² and dried in an oven at 120 ° C. for 2 minutes to form a pressure-sensitive adhesive layer, and then, on the pressure-sensitive adhesive layer surface, a base sheet having the toner transfer layer described above, By sticking the toner transfer layer so as to be the outermost layer, each pressure-sensitive adhesive sheet composed of the product of Example of the present invention and the product of Comparative Example was obtained.

[Experiment] The coefficient of kinetic friction of the toner transfer layer surface of each of the pressure-sensitive adhesive sheets obtained in the examples and comparative examples (the surface of the high-quality paper forming the base sheet in the pressure-sensitive adhesive sheet of comparative example 1) was J . TAPPI No. According to No. 30-79, using a steel plate, the moving speed of the lower movable beam of the tensile tester was 400 mm / min. Tested. The results are shown in [Table 2].

The surface smoothness of the surface of the toner transfer layer of each of the pressure-sensitive adhesive sheets obtained in Examples and Comparative Examples (the surface of the high-quality paper forming the base sheet in the pressure-sensitive adhesive sheet of Comparative Example 1) was determined as follows. It was measured by a grinding type smoothness tester. The results are shown in [Table 2].

Further, a laser printer “Fuji Xerox Co., Ltd .: Vivece 550” was applied to the surface of the toner transfer layer of each adhesive sheet (the surface of the high-quality paper forming the base sheet in the adhesive sheet of Comparative Example 1). After performing the entire recording for the test using, the adhesive surface of the scotch mending tape is adhered to the formation surface of the recorded image, and then peeled off to remove the toner adhered to the scotch mending tape. The degree of toner fixability on the surface of the toner transfer layer was tested according to presence, absence, and adhesion amount.

The results of this test are shown in Table 2. In Table 2, there is little adhesion of toner to the adhesive surface of the scotch mending tape. ······ Displayed with ○.

Further, the paper-passing property was tested using a printer based on Epson LP-9000. This test result,
In Table 2, one or more paper passing failures indicate that the adhesive sheet 5
× occurred when the number of sheets was 0 or less ··· ×, where one or more paper passing failures occurred when the number of adhesive sheets was from 51 sheets to 500 sheets ···
No sheet passing failure occurs up to 501 sheets of adhesive sheet ...
○, indicated by In addition, one piece of the adhesive sheet was cut into an A4 size plate.

[0046]

[Table 2]

As is clear from the above Examples and Comparative Examples, the amount of the non-film-forming acrylate polymer fine particles in the toner transfer layer was increased, and the dynamic friction coefficient and surface smoothness of the toner transfer layer were increased. And can be reduced,
As a result, it is possible to improve the paper passing property without deteriorating the toner fixing property of the toner transfer layer that does not contain the non-film-forming acrylate polymer fine particles.

Also, by lowering the coefficient of kinetic friction of the toner transfer layer by adding a lubricant, it is possible to improve the paper passing property of the pressure-sensitive adhesive sheet. It can be seen that the toner fixability cannot be maintained (Comparative Example 6).

[0049]

According to the present invention, there is provided an adhesive sheet having a toner transfer layer on one surface of a substrate sheet, and a release sheet adhered to the other surface of the substrate sheet via an adhesive layer. The toner transfer layer is composed of an acrylic resin layer containing non-film-forming acrylate polymer fine particles as a filler, and the surface of the toner transfer layer has a coefficient of dynamic friction of 0.
It consists of an adhesive sheet in the range of 120 to 0.160.

According to the pressure-sensitive adhesive sheet of the present invention having the above-described structure, the toner sheet has excellent toner fixability when forming a recording image formed of a transfer layer using powder toner, and when passed through an electrophotographic transfer type copying machine or printer. It becomes an adhesive sheet with excellent paper passing properties.

Claims (2)

[Claims] 1. An adhesive sheet having a toner transfer layer on one surface of a substrate sheet and a release sheet adhered to the other surface of the substrate sheet via an adhesive layer. Is composed of an acrylic resin layer containing non-film-forming acrylic acid ester polymer fine particles as a filler, and the coefficient of kinetic friction of the surface of the toner transfer layer is 0.120 to
An adhesive sheet characterized by being within the range of 0.160. 2. The pressure-sensitive adhesive sheet according to claim 1, wherein the coefficient of kinetic friction of the surface of the toner transfer layer is in the range of 0.140 to 0.150.