JPS6330158B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat-sensitive stencil printing base paper in which a film and a porous thin paper are laminated, and a method for producing the same.

Various types of base paper for thermal stencil printing (hereinafter referred to as base paper) have been proposed in the past, but the main ones are thin thermoplastic films (vinylidene chloride film, polyester film, polypropylene film, etc.). and porous tissue paper (natural fibers, synthetic fibers, semi-synthetic fibers, and mixtures thereof). The principle of plate making using this base paper for thermal stencil printing is to overlap the original and base paper, irradiate this with infrared rays, and utilize the difference in heat absorption rate between the image and non-image areas of the original to absorb heat. The film is perforated only in areas corresponding to image areas with good efficiency. A copy identical to the original can be obtained by loading the base paper made in this way into a mimeograph machine and supplying ink from the porous thin paper side.

Now, in such a base paper, as shown in the figure, the ink 7 must pass through the components of the base paper 1, such as the porous thin paper 2, the adhesive 3, and the perforations 4 of the film, to reach the printing paper 6. However, porous tissue paper and ink do not blend together immediately, and the first or second prints are usually faded or faded. This is called a trial print and is a waste. In particular, when porous thin paper is made from fine denier (fibers of 0.1 denier or less), the fibers are dense, so it is necessary to waste about 30 sheets to obtain a relatively good print. Ta. By using this waste printing to blend the ink with the porous tissue paper, good prints can be obtained.

The present invention aims to eliminate unnecessary printing (including trial printing) in order to obtain good printed matter as described above.
A surfactant is applied to the porous thin paper so that the ink is immediately blended with the porous thin paper and the ink can easily pass through the perforated portions 4. That is, as shown in the figure, the ink 7 can easily pass through the porous thin paper 2 and the perforated portion 4 of the film by utilizing the interfacial effect of the surfactant. Of course, even if a surfactant is added to the ink, some effect can be expected, but there is still a problem that it does not blend quickly with porous tissue paper, and it would have been better to apply it to porous tissue paper. Furthermore, if it is used in ink, it is expected that problems will arise in drying properties depending on its concentration.

Note that the type of ink, the material of the porous tissue paper, and the type of surfactant are all related to each other.
It is difficult to unconditionally specify the type of surfactant. Therefore, the type of surfactant should be determined after the materials of the ink and porous thin paper are determined.

A more detailed explanation will be given below using some examples.

Example 1 A base paper made by laminating a porous thin paper with a basis weight of 5 g/m ² made of a 3μ polyester film (Torel Mirror #3) and a 0.03 denier polypropylene with polyvinyl acetate,
NBL Energen 105 and NS soap (both manufactured by Kao) were applied respectively. This was used as a base paper to make plates using a heat-sensitive flash plate making machine, and mimeograph printing was performed. The ink used was Ricoh Toshiya Ink S.
-30.

As a result, almost no improvement effect was observed for NS soap, but for Pellex NBL and Emulgen 105, good prints were obtained from approximately the third page (30 wasted prints without surfactant application). ).

Example 2 As a result of using lithographic ink (manufactured by Riso Kagaku Co., Ltd.) as the ink on the same base paper as in Example 1, a remarkable effect was observed for Emulgen 105.
Good prints were obtained from the 7th sheet onwards.

Example 3 3μ polyester film (Tolerumina product number
3C) and rayon paper with a basis weight of 8 g/m ² laminated with polyvinyl acetate, sodium stearate, Pellex NBL, Emulgen
105 and Emar 80 (both manufactured by Kao) were applied to porous tissue paper. Ink is Ricoh S-30
And so. As a result, Perex NBL, Emulgen
105 and Emaar 80 both produced good prints on the first sheet. Regarding sodium stearate, the first sheet was blurred as in the case of no application.

In the production of base paper for heat-sensitive stencil printing in which porous thin paper is impregnated with a surfactant as described above, first, the film and the porous thin paper are laminated, and then a surfactant solution is impregnated from the porous thin paper side. It is necessary to dry the film at a temperature below which the film does not change. This is because if a surfactant is applied to the porous tissue paper first, lamination with the film becomes extremely difficult.

As mentioned above, in thermal stencil printing base paper, by applying a surfactant to porous thin paper,
Wasteful printing until good printed matter is obtained is reduced.

[Brief explanation of the drawing]

The figure is a schematic diagram showing how ink passes through a base paper and is printed. DESCRIPTION OF SYMBOLS 1... Base paper, 2... Porous thin paper, 3... Adhesive, 4... Perforated part, 5... Film, 6... Printing paper.

Claims (1)

[Scope of Claims] 1. A base paper for heat-sensitive stencil printing, which is a base paper for heat-sensitive stencil printing in which a porous thin paper is laminated to a film, and the porous thin paper is coated with a surfactant. 2. A method for producing base paper for thermal stencil printing, which comprises laminating a porous thin paper onto a film, applying a surfactant solution from the porous thin paper side, and drying at a temperature below which the film does not substantially change.