JPH07292328A - Adhesive tape using porous base material - Google Patents

Abstract

PURPOSE:To obtain an adhesive tape excellent in peelability by forming a filler layer having peeling properties on one face of a porous base material through a specific process, thus showing increased production efficiency because the peelability is given to the filler layer through a one-step process. CONSTITUTION:A porous base material such as Japanese paper or nonwoven fabric is coated with a coating agent comprising (A) a synthetic resin emulsion or suspension such as vinyl chlorideacrylic acid copolymer and (B) an emulsion or suspension of a peeling agent such as a silicone and dried on one face to form a peeling layer, simultaneously an adhesive layer is formed on the other to give the object product. The components A and B are preferably selected in combination of the same ionic type, for example, nonionic and nonionic, cationic and cationic or anionic and anionic, because these combinations do not break the emulsion or suspension structures, when they are mixed. Further, it is preferred that the components (A) and (B) are mixed at a ratio of 100:1 on the solid basis.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-sensitive adhesive tape obtained by subjecting a porous substrate such as paper or non-woven fabric to one side with a sealing treatment and a peeling treatment.

[0002]

2. Description of the Related Art An adhesive tape, which is a porous substrate made of fibrous material such as paper or non-woven fabric and provided with an adhesive layer, is wound into a roll or laminated to make contact with the adhesive layer. The base material adheres to the base material, and if the base material is peeled off during use, the base material is broken and cannot be peeled off. It is considered that this is because the peeling force of the adhesive surface is concentrated on the fluffy fibers on the back surface of the substrate.

For this reason, when Japanese paper is used as a substrate, fluff is formed by coating or impregnating a polyolefin resin such as polyethylene or polypropylene on the side opposite to the adhesive-coated surface, or by coating clay or starch. The fiber is held down and fixed.

For example, Japanese Patent Publication No. 55-12152 discloses that one side of Japanese paper impregnated with a fluororesin and a fixing aid is coated with an adhesive, and the other side is coated with a solvent-based release agent. There is described a Washi adhesive tape in which penetration of a release agent is suppressed without impairing the flexibility of Washi.

Further, in Japanese Patent Laid-Open No. 2-151427,
A fibrous base material is impregnated with a rubber-based or synthetic resin, and the amount of impregnation on both sides of the base material is made different to give the base material flexibility and increase the physical strength of the first surface layer of the base material. To improve the ability to follow the adherend surface,
An adhesive tape intended to be peeled off without tearing or breaking at the time of peeling is described.

[0006]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
The Japanese paper pressure-sensitive adhesive tape described in Japanese Patent No. 152 requires two steps of once adding a fluorine-based resin and a fixing aid to Japanese paper, and applying a solvent-based release agent so that one surface of this Japanese paper does not penetrate to the back surface. . Moreover, the solvent-based release agent easily penetrates the porous substrate such as Japanese paper and reaches the back surface, so that it is difficult to adjust the viscosity and set the coating amount.

Further, the adhesive tape described in Japanese Patent Application Laid-Open No. 2-151427 requires two steps of impregnating a base material with a rubber-based or synthetic resin to form a sealing layer and applying an adhesive on both surfaces. However, it is not intended to form a peeling layer.

The present invention solves the above-mentioned problems of the prior art by providing a sealing layer on one surface of a porous substrate and imparting releasability to the sealing layer in one step. An object of the present invention is to provide an adhesive tape having excellent releasability using a material.

[0009]

A pressure-sensitive adhesive tape using a porous substrate of the present invention is a pressure-sensitive adhesive tape having a release layer on one side of a porous substrate and a pressure-sensitive adhesive layer on the other side. The layer is formed by coating and drying a coating agent obtained by mixing a synthetic resin in an emulsion or suspension state and a release agent in an emulsion or suspension state.

As the porous substrate used in the present invention,
Examples thereof include natural fibers such as pulp and Manila hemp, and Japanese paper, kraft paper, woven cloth or non-woven cloth prepared by mixing vinylon and the like with these, and these are characterized by excellent hand-cutting properties. Examples of the release layer applied to one surface of the above-mentioned porous substrate include an emulsion or suspension in which a synthetic resin such as vinyl chloride-acrylic acid copolymer is dispersed in water, silicon, and a long-chain alkyl group-containing polymer. It is used as a coating agent in which an emulsion or suspension in which a release agent such as polyethylene, shellac or the like is dispersed is mixed.

When a synthetic resin dispersed as an emulsion or suspension is applied to a substrate,
Synthetic resin particles are accumulated between the fibers of the base material to form a sealing layer on the surface of the base material and in the vicinity of the surface, and at the same time, fluffing on the surface of the base material is suppressed and fixed. However, sufficient releasability cannot be obtained only with synthetic resin particles. Further, the release agent is absorbed inside the base material only by the emulsion or suspension in which the release agent is dispersed, and the filling layer is not formed. Therefore,
By using both as an emulsion or suspension mixed with each other, the release agent dispersed in water accumulates on the surface of the base material together with the synthetic resin, so that good release properties can be obtained.

The emulsion or suspension in which the synthetic resin is dispersed and the emulsion or suspension in which the release agent is dispersed are selected from nonions, cations, or anions. It is preferable because the emulsion or suspension structure is not destroyed.

As described above, in order to form the sealing layer with the synthetic resin particles and to impart the releasability to the surface of the base material with the release agent particles, the emulsion or suspension in which the synthetic resin particles are dispersed and the release agent are used. The dispersed emulsion or suspension preferably has a solid content ratio of about 100: 1, but the ratio can be appropriately changed depending on the solid content of both emulsions or suspensions.

Although the synthetic resin and the release agent particles are slightly impregnated with the water inside the base material, most of them are on the surface of the base material and in the vicinity thereof because the particle size is larger than the gap between the fibers constituting the base material. Accumulated. The water impregnated inside the base material evaporates and disappears in the subsequent drying step, so that even if the back surface of the base material is coated with the pressure-sensitive adhesive, the pressure-sensitive adhesive is strongly adhered to the base material.

For forming the pressure-sensitive adhesive layer, usual means are used,
It may be formed by directly applying and drying a pressure-sensitive adhesive solution or pressure-sensitive adhesive emulsion of natural rubber type, synthetic rubber type, acrylic type or the like on a substrate, or may be formed by a transfer method.
However, in the case of the solution method, it is necessary to select one in which the solvent does not attack the peeling layer on the back surface.

[0016]

[Function] Since the synthetic resin forming the sealing layer is dispersed in an emulsion or suspension state and applied to the base material, the synthetic resin particles accumulate between the fibers near the application surface of the base material, and A filling layer is formed on the surface.
At the same time, fibers on the surface of the base material are fixed to suppress fluffing, and the strength of the base material in the thickness direction is improved. Further, since the release agent dispersed in water as an emulsion or suspension accumulates on the surface of the base material together with the synthetic resin, a good release property can be obtained for the adhesive surface laminated on the surface.

[0017]

EXAMPLE Next, an example of an adhesive tape using the porous substrate according to the present invention will be described. (Example 1) A polyethyleneimine-based release agent emulsion (manufactured by Nippon Shokubai Co., Ltd.) was added to a resin emulsion (manufactured by Nisshin Chemical Industry Co., Ltd., trade name: VINIFRAN 270) obtained by dispersing a vinyl chloride-acrylic acid ester copolymer in water. , Product name: K
X-RP18W03) is mixed so that the solid content ratio is 100: 1, and polyvinyl alcohol is used as a binder, and vinylon, pulp and Manila hemp are mixed and made into one side of a mixed paper having a basis weight of 30 g / m ^2. Then, a solid content of 15 g / m ² was applied and dried to perform back surface peeling treatment. Furthermore, an acrylic pressure-sensitive adhesive layer was formed on the other surface of the above-mentioned mixed paper by a transfer method so as to have a thickness of 30 μm to obtain an adhesive tape.

Comparative Example 1 An adhesive tape was prepared in the same manner as in Example 1 except that a coating agent containing no release agent emulsion was coated on a mixed paper at a solid content of 15 g / m ² and dried.

(Example 2) A rubber adhesive was applied to the other surface of the mixed paper which was subjected to the backside peeling treatment in Example 1 using a reverse coater so as to have a thickness of 30 µm and dried to obtain an adhesive tape.

(Comparative Example 2) A resin emulsion alone was applied to a mixed paper at a solid content of 15 g / m ² and dried, and a rubber adhesive was applied to the other surface to a thickness of 30 μm using a reverse coater and dried. It was an adhesive tape.

In order to evaluate the peeling effect, the above-mentioned Example 1 was used.
2 and Comparative Examples 1 and 2 were cut into a width of 15 mm, and a Washi adhesive tape (manufactured by Sekisui Chemical Co., Ltd., trade name: Paper Adhesive Tape # 653) was attached to the surface coated with the coating agent, and a load of 2 kg was applied. I crimped back and forth once.
The 180-degree peel force when the bonded Japanese paper adhesive tape was peeled at a high speed of 100 m / min was measured. The results are shown in Table 1.

[0022]

[Table 1]

As is clear from Table 1, Examples 1 and 2 have excellent releasability even when peeled at a high speed. However, it can be seen that the peelability of Comparative Examples 1 and 2 is very poor.

[0024]

The pressure-sensitive adhesive tape using the porous base material of the present invention has the above-mentioned constitution, and the sealing layer having peeling property is formed on one surface of the porous base material made of fibrous material. It is an excellent pressure-sensitive adhesive tape that can be peeled off at a high speed even when the pressure-sensitive adhesive layer provided on the other surface of the base material is stacked by rolling or stacking in a roll shape.

Further, in order to produce the adhesive tape of the present invention,
A synthetic resin dispersed as an emulsion or suspension and a release agent dispersed in water as an emulsion or suspension are mixed and simultaneously applied as a coating agent to the substrate, so a sealing layer is formed on one side of the substrate. Since the step of providing and the operation of imparting releasability to the sealing layer can be performed in one step, the manufacturing can be performed very efficiently.

Claims (1)

[Claims] 1. A pressure-sensitive adhesive tape having a release layer on one surface of a porous substrate and an adhesive layer on the other surface, wherein the release layer is a synthetic resin in an emulsion or suspension state and a release in an emulsion or suspension state. A pressure-sensitive adhesive tape using a porous base material, which is formed by applying and drying a coating agent mixed with an agent.