JPS63233890A - Thermal stencil paper - Google Patents

Abstract

PURPOSE:To enhance productivity and solvent resistance, by performing lamination by using a UV-curable type adhesive, in producing a thermal stencil paper through laminating a porous base with a thermoplastic synthetic resin film. CONSTITUTION:A UV-curable type adhesive may be generally a mixture of a polyester acrylate, urethane acrylate, epoxy acrylate or polyol acrylate with a photopolymerization initiator, and is particularly preferably a mixture comprising urethane acrylate as a main constituent. Lamination of a thermoplastic synthetic resin film with a porous base is performed by applying the adhesive to the surface of the resin film, pressing the porous base against the applied adhesive by a pressure of, for example, at least about 2 kg/m<2>, and irradiation with UV rays is conducted for at least 0.04 sec/cm from the film side by a UV lamp having an output of 80 W/cm. The resin film is, for example, a polyester film, and the thickness thereof is preferably 1-6 mum. The thickness of the porous base is preferably 15-40 mum.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a heat-sensitive stencil paper, and more particularly to a heat-sensitive stencil paper made by bonding a porous support and a thermoplastic synthetic resin film together using an adhesive. .

[Conventional technology]

Conventionally, heat-sensitive stencil paper is known, which is made by laminating a thermoplastic synthetic resin film such as a polyester film with an adhesive onto a support such as porous tissue paper. Adhesives used in this case include (1) solvent-based or water-based adhesives, (2) reactive systems such as room temperature curing type or thermosetting type,
(3) Ho-nodomelt type products are known. (1)
In the case of solvent-based systems (for example, Japanese Patent Publication No. 47-1188)
By using a solvent, the range of resin selection can be expanded, and the coating amount can be easily controlled by setting dilution conditions, but the solvent must be recovered, which poses problems in maintaining the working environment. be. In addition, regarding the physical properties of the product after lamination, it has the disadvantage that solvent resistance is poor and the inks that can be used are limited.

On the other hand, in the case of aqueous systems (Japanese Patent Publication No. 1187/1987), there are almost no problems in terms of the working environment, but the amount of heat required for drying is enormous, and moisture can damage the substrate (porous support).
The disadvantage is that the dimensional stability of the material is impaired.

On the other hand, in the case of (2) and (3), solvent-free systems do not involve the use of organic solvents compared to solvent-based systems, so there are almost no problems in the working environment such as adverse effects on the human body. In the case of hardening type (Japanese Unexamined Patent Publication No. 153697/1989),
The curing speed is slow, and the residence time required to check the physical properties of the product after manufacture is long, which is disadvantageous from the viewpoint of improving productivity. On the other hand, in the case of thermosetting adhesives, a considerable amount of heat is required to cure the adhesive, and as a result, the porous support and thermoplastic synthetic resin film, which are the base materials, are affected by heat and shrink, causing the product to deteriorate. Curls are more likely to occur. In addition, in the case of (3) true melt adhesives, like other solvent-free adhesives, the advantage is that the work environment is easy to maintain, but in this case too, the influence of heat on the base material is It becomes a problem. Also, the melting point,
Many of them have high melt viscosity, and there is a problem in that production control is difficult when maintaining a low coating amount.

[Problem that the invention seeks to solve]

SUMMARY OF THE INVENTION An object of the present invention is to provide a heat-sensitive stencil paper that eliminates the drawbacks of the prior art, has almost no problems in the working environment, has excellent productivity, and has excellent solvent resistance.

[Means for solving problems]

The present invention is a heat-sensitive stencil paper formed by laminating a porous support and a thermoplastic synthetic resin film, and is characterized in that the lamination is carried out using an ultraviolet curable adhesive.

As the thermoplastic synthetic resin film used in the present invention, for example, polyester film, polycarbonate film, polypropylene film, polyvinyl chloride film, etc. can be used, and the thickness thereof is preferably 10μ or less,
The thermoplastic synthetic resin film, which is more preferably 1 to 6 μm, is usually a biaxially stretched film, and preferably has a stretching ratio of 150 to 250% in both the longitudinal and transverse directions.

As the porous support, synthetic IJJi fibers such as polyester fibers, vinylon fibers, and nylon fibers, each having a fineness of 3 deniers or less, or natural fibers such as manila hemp, mulberry, mitsumata, pulp, etc. alone or in mixtures, and other thermoplastics may be used. A material capable of absorbing the molten resin of the synthetic resin film 4 can be used, and its weight is 6 to 14 g.
/n? , especially preferably 8 to 14 g/m, and the thickness is 1
0 to 60μ, particularly 15 to 40μ is preferred.

The UV-curable adhesive used in the present invention generally includes polyester acrylate, urethane acrylate,
Examples include blends of epoxy acrylates, polyol acrylates, and photopolymerization initiators, but among the above, those containing urethane acrylate as a main component are particularly preferred. Tokyo Ink Co., Ltd. R-001, AH1 Toagosei (
Examples include UVX-196 manufactured by Co., Ltd.

In order to bond the thermoplastic synthetic resin film and the porous support, an ultraviolet curable adhesive is applied to the surface of the thermoplastic resin film, and the porous support is placed on the surface of the thermoplastic resin film, for example.
After crimping with a pressure of more than kg/rd, the film is irradiated with ultraviolet rays for more than 0.04 seconds/cm using an ultraviolet lamp with an output of 80 W/cm.

Hereinafter, the present invention will be specifically explained with reference to Examples.

〔Example〕

Example 1 A polyester film (thickness 2μ
) UV-curable adhesive (manufactured by Tokyo Ink Co., Ltd.) on the surface
-001) was applied, and Manila hemp tissue paper (8.5 g/nf) was pressed as a porous support. Immediately thereafter, apply an ultraviolet irradiation device (manufactured by Nippon Battery Co., Ltd., High Cure System, Hl Cure Sys Lem DHC40
The ultraviolet curable adhesive was cured by irradiation with ultraviolet rays at 3 DB and an output of 80 W/cm 2 ), and the film and support were bonded together. The traveling speed of the film and support at this time was 15 m/min. Next, a release agent containing silicone resin and silicone oil in a weight ratio of 1:1 was applied to the film surface of the base paper using a roll coater. The coating weight was 0.2 g/rd. The heat-sensitive stencil paper prepared as described above was plate-made and printed using a digital plate-making printing machine (manufactured by Riso Kagaku Kogyo Co., Ltd., Lingraph 007DI [IN) using a thermal head. Further, the heat-sensitive stencil paper was immersed in ethyl acetate, toluene, and methanol for 2 hours at 25° C. to examine the peeling state (solvent resistance) between the film and the support.

The results are shown in Table 1.

Margins below Table 1 * △ means "the image is unclear and there is some blurring", and O means "the image is clear and there is no blurring".

Examples 2 and 3 As an ultraviolet curing adhesive, UVX- manufactured by Toagosei Co., Ltd.
196 and AH manufactured by Tokyo Ink Co., Ltd. were used, and the coating amount was 1.1 g/rr? and 1.3g/rr? The film and the support were bonded together under the same conditions as in Example 1 except that. When the obtained thermal stencil paper was plate-made and printed using a digital plate-making printing machine in the same manner as in Example 1, a clear image faithful to the original could be obtained.

〔Effect of the invention〕

According to the present invention, the following effects can be obtained by using an ultraviolet curable adhesive.

(1) Since no solvent is used, there are almost no problems in the working environment.

(2) It cures instantly by irradiating it with ultraviolet rays, so it has excellent productivity.

(3) The crosslinking density of the resin is high, and the product has excellent solvent resistance.

(4) Since the resin viscosity before curing can be set low, stable production can be achieved with a low coating rate.

Claims (1)

[Claims] (1) A heat-sensitive stencil paper formed by laminating a porous support and a thermoplastic synthetic resin film, characterized in that the lamination is carried out using an ultraviolet curable adhesive.