JPH01150581A - Thermal stencil paper and its production - Google Patents

Abstract

PURPOSE:To economically obtain high performance thermal stencil paper, by laminating a thermoplastic resin layer to one surface of a porous support. CONSTITUTION:A thermoplastic resin 2 is melted and extruded into a film shape from a T-die extruder 6 while a support 1 is supplied from a raw web roll 4 and the formed thermoplastic resin film is brought into contact with the support 1 at the place of cooling rolls 5, 5' to laminate both of them under pressure and the formed laminate is taken up by a take-up roll 7 to obtain thermal stencil paper. It is necessary to form the support 1 from a porous, body capable of permitting printing ink to be used to pass at the time of printing and, for example, paper, synthetic paper or blended fiber paper having a basis wt. of about 8-12g/m<2> is advantageously used. As the thermoplastic resin 2, for example, a polyvinyl chloride resin or a polystyrene resin can be used. A sticking preventing layer 3 can be formed on the thermoplastic resin layer 2. As mentioned above, by forming the thermoplastic resin layer by an extrusion coating method, the thermoplastic resin at the time of the contact with the support is in a molten or softened state and, therefore, said resin is sufficiently bonded to the porous support and the use of an adhesive becomes unnecessary.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a thermal mimeograph base paper and a method for producing the same, and more specifically, an object of the present invention is to economically provide a high-performance thermal mimeograph base paper.

(Prior Art) Conventionally, mimeograph printing has been widely used as a simple printing method, and this method uses a thermoplastic film layer laminated on the surface of a suitable support such as paper as a heat-sensitive mimeograph base paper. Printing is performed using a thermal head or infrared rays, the thermoplastic film layer is heated and melted to form image-shaped perforations, and printing is performed on a printing material such as paper by passing printing ink from the support side.

(Problem to be Solved by the Invention) The thermal mimeograph base paper used in the conventional thermal mimeographing method described above is generally formed by laminating a thin thermoplastic film layer of several μm on the surface of a porous support such as paper. However, there are the following problems.

(1) An adhesive is required when laminating a thermoplastic film on a porous support, which is a complicated process and causes wrinkles.

(2) The above adhesive layer must also be thermoplastic so that it can be perforated by heat, so strong adhesives such as thermosetting adhesives cannot be used, and therefore sufficient adhesive strength cannot be obtained. .

Furthermore, for the same reason, during printing, the adhesive strength is reduced by the solvent components in the printing ink, and the thermoplastic film layer is peeled off by a thermal head etc., resulting in problems in printing durability, such as poor printing.

(3) Since an organic solvent solution or emulsion of a thermoplastic resin is usually used as the adhesive, a drying process and an aging process are required, resulting in high process costs.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to overcome the above-mentioned drawbacks and to economically provide an excellent heat-sensitive mimeograph base paper.

(Means for solving problems) The above objects are achieved by the present invention as described below.

That is, the present invention consists of two inventions, the first invention being:
A heat-sensitive mimeograph base paper characterized in that a thermoplastic resin layer is laminated on one side of a porous support, and the second invention is a thermoplastic resin layer laminated on one side of a porous support A method for producing a heat-sensitive mimeograph base paper, characterized in that the resin layer is formed by an extrusion coating method.

(Function) By forming the thermoplastic resin layer of the heat-sensitive mimeograph base paper using an extrusion coating method, the thermoplastic resin is in a molten or softened state when it comes into contact with the support, so that it can sufficiently adhere to the porous support. The use of adhesive becomes unnecessary.

(Preferred Embodiments) Next, the present invention will be described in more detail by citing preferred embodiments.

FIG. 1 is a diagram schematically showing the manufacturing method of the present invention. The resin layer 2 is characterized in that it is formed by extrusion coating.

More specifically, as schematically shown in FIG. 1, T-die extrusion is performed in which the support 1 is supplied from the raw roll 4 and the thermoplastic resin 2 is melt-extruded at the cooling roll 5.5'. Machine 6
It comes into contact with and presses the thermoplastic resin film 2 extruded into a film shape to laminate the two, and is wound up on a take-up roll 7 to obtain the desired thermal mimeograph base paper.

Although not shown in the present invention, in addition to the above steps, the resin layer 2 may be made into a composite layer by co-extrusion coating different resins, and in order to form a smooth surface of the resin layer 2. Furthermore, it is also possible to form a very thin resin layer 2 with a smooth surface by co-extrusion coating the resin layer 2 with another non-adhesive resin and then peeling off the non-adhesive resin layer.

The mimeograph base paper of the present invention obtained as described above is characterized by having a thermoplastic resin layer 2 laminated on one surface of a porous support 1, as shown in the circle in FIG.

The support 1 used in the present invention needs to be porous so that the printing ink used during printing can pass through it, and examples include various types of paper, especially coarse paper such as Japanese paper, rayon, vinyl , synthetic paper made of chemical fibers such as polyester, acrylonitrile, and mixed paper of chemical fibers and natural fibers, etc., which are used as supports for conventional heat-sensitive mimeograph base paper, can be used in the present invention, and are not particularly limited. For example, paper, synthetic paper, mixed paper, etc. having a basis weight of about 8 to 12 g/rn' are advantageously used. Incidentally, these supports 1 may be previously subjected to a corona discharge treatment in order to improve adhesion to the resin layer 2.

The thermoplastic resin layer 2 itself laminated on the surface of the support 1 is also made of a material used in conventional heat-sensitive mimeograph base paper, such as polyvinyl chloride resin, vinyl chloride-vinylidene chloride copolymer resin, polyester resin. ,polyethylene,
Any polyolefin resin 1 such as polypropylene, polystyrene resin, etc. can be used, and there are no particular limitations.

These thermoplastic resin layers 2 have a thickness of 20 μm or less, preferably 10 μm or less, and optimally 1 to 5 μm so that perforations can be easily formed by heating means such as a thermal head.

The thermal mimeograph base paper obtained by the method described above has excellent plate-making properties, but when forming the mimeograph holes by heating the thermoplastic resin layer 2 with a thermal head or other method, depending on the conditions, the thermal may stick to the thermoplastic resin layer 2 and destroy the thermoplastic resin layer 2, or when a copying hole is formed by exposure through a positive original film, the positive original film may become sticky.

In order to solve this drawback, an anti-adhesive layer 3 can be formed on the thermoplastic resin layer 2 as shown in the second figure.

This anti-adhesion layer 3 needs to be heat-meltable and non-adhesive. Examples of such heat-meltable resins include fluororesins such as polytetrafluoroethylene, polychlorotrifluoroethylene, tetrafluoroethylene-hexafluoroethylene copolymers, polyvinylidene fluoride, silicone resins, epoxy resins,
Melamine resin, phenol resin, polyimide resin, polyvinyl acetal resin, polyvinyl butyral resin, polyoxyethylene terephthalate, polyethylene oxide resin, etc. can be used, and a surfactant may also be used to improve the slipperiness of the anti-adhesive layer 3 to be formed. For example, fatty acid metal salts such as metal salts of lithium, potassium, sodium, calcium, barium, aluminum such as stearic acid, palmitic acid, lauric acid, oleic acid, phosphate ester type surfactants, polyoxyethylene type surfactants, etc. A surfactant, such as a mono- or dialkyl phosphate ester or a tri(polyoxyethylene alkyl ether) phosphate, is added in an amount of about 10 to 200 parts per 100 parts by weight of the resin.
It is preferable to form an anti-adhesive layer 3 in addition in the proportion of parts by weight.

The anti-adhesion layer 3 made of the above resin (and surfactant) is
These materials may be dissolved or dispersed in an organic solvent or water to prepare a coating liquid, and this may be applied to the surface of the thermoplastic resin layer 2 by any method. The thickness of the anti-adhesive layer 3 is
If it is too thick, the heat sensitivity will decrease and the formation of perforations will be insufficient, so a thinner one is preferable, for example, a thickness of about 0.05 to 10 μm is preferable. The timing of forming the anti-adhesion layer 3 is not particularly limited, and may be after or during the formation of the heat-sensitive mimeograph base paper.

(Effects) According to the present invention as described above, by forming the thermoplastic resin layer of the heat-sensitive mimeograph base paper by an extrusion coating method, the thermoplastic resin is in a molten or softened state when it comes into contact with the support, so that it becomes porous. It adheres well to the quality support, eliminates the need for adhesives, easily solves various problems caused by the use of adhesives, and provides a high-performance thermal mimeograph base paper economically.

(Example) Hereinafter, the present invention will be explained in more detail with reference to Examples.

In the text, parts or percentages are based on weight unless otherwise specified.

Example 1 Porous thin paper (Stencil Vapor, manufactured by Nippon Shigyo, 12
g/rn") at 15 W/rn'min to obtain treated paper. On the treated surface of this treated paper, high-density polyethylene (old 30% polyethylene, manufactured by Shirataki Maruzen Polyethylene) was applied using a T-die. It was coated to a thickness of 8 μm using an extrusion coating method (processing resin temperature 280°C). An ink having the following composition was applied to the resin layer surface of this laminate using a direct gravure method so that the solid content when dried was 0.08 g/
A heat-sensitive mimeograph base paper of the present invention was obtained by coating the paper to form an anti-adhesive layer.

Silicone-modified acrylic resin (MOP41, manufactured by Gosei Ink) 100 parts Organotin compound (
MOP curing type, manufactured by Suffix Ink) 0.4 parts Toluene 600 parts Isopropyl alcohol 300 parts'' - When the plate was made using a heat-sensitive flash plate making machine using a heat-sensitive mimeograph base paper and mimeographed, there were no problems in plate-making properties and printing durability. There wasn't.

Example 2 Polyester and polyethylene were coextruded and coated using a T-die coextrusion method so that the treated paper of Example 1 and the polyester were in contact with each other to form a laminate. The thickness of the polyester layer was 2 μm, while the thickness of the polyethylene layer was 40 μm.

Next, after peeling off the polyethylene layer, an anti-adhesion layer having a thickness of 0.1 ttm was formed on the surface of the polyester layer using an ink having the composition shown below to obtain a thermal mimeograph base paper of the present invention.

Polyvinyl butyral (S-LEC BX-1, manufactured by Block Chemical) 50 parts Surfactant (Blysurf 208, manufactured by Dai-Kogyaku Yakuhin)
50 parts toluene
450 parts methyl ethyl ketone 450 parts Recover Riboot 5S870 using the above heat-sensitive mimeograph base paper
When plate making and printing were carried out using the same machine, there were no failures due to adhesion of the thermal head, and good printed matter was obtained with excellent printing durability.

[Brief explanation of the drawing]

FIG. 1 is a diagram schematically showing the manufacturing method of the present invention, and FIG. 2 is a diagram schematically showing a cross section of an example of a thermal mimeograph base paper produced by the manufacturing method of the present invention. 1: Support 2: Resin layer 3: Anti-adhesive layer 4: Original wheel roll 5.5'; Cooling roll 6: T-die extruder 7; Winding roll

Claims (5)

[Claims] (1) A heat-sensitive mimeograph base paper characterized by having a thermoplastic resin layer laminated on one side of a porous support. (2) The thermal mimeograph base paper according to claim (1), wherein the resin layer is formed by an extrusion coating method. (3) The thermal mimeograph base paper according to claim (1), wherein an anti-adhesive layer is formed on the surface of the resin layer. (4) A method for producing a thermal mimeograph base paper comprising a thermoplastic resin layer laminated on one side of a porous support, the resin layer being formed by an extrusion coating method. (5) The method for producing a thermal mimeograph base paper according to claim (4), wherein an anti-adhesive layer is formed on the surface of the resin layer.