JPS6233689A - Thermal stencil base paper - Google Patents

Abstract

PURPOSE:To enable a plate to be made direct by an irradiation of electromagnetic wave such as laser beam, by laminating a film made of themoplastic resin containing electromagnetic wave absorbing substance on a substrate made of porous member. CONSTITUTION:A thermal stencil base paper 3 consists of a substrate 1 and a film 2 of thermoplastic material laminated on one side surface thereof. The film 2 including fine powders of graphite and pigments of kinds etc. as electromagnetic wave absorbing substance is drawn to 1-6mum in thickness. Selective irradiation of laser beam on the thermal stencil base paper 3 results in the film 2 being perforated at the portion thereof which has been irradiated by laser beam, thus enabling the image corresponding to an original image to be formed on the thermal stencil base paper.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a heat-sensitive stencil paper that can be used in printing devices such as rotary mimeograph machines, and is particularly suitable for laser plate making.

(B) Conventional technology Conventional heat-sensitive stencil paper is difficult to absorb electromagnetic waves, as shown in, for example, JP-A-59-2895, JP-A-59-2896, JP-A-59-16793, etc. It is made by pasting a transparent or translucent thermoplastic film (eg, polyester film or polyethylene film) and a support made of a porous member (eg, rayon paper).

First, the thermoplastic film side of the heat-sensitive stencil paper is superimposed on the original, and then infrared rays are irradiated from the heat-sensitive stencil paper side. The film is selectively indirectly heated by heat generation, and perforations are formed in the film along the original image.

Therefore, in the heat-sensitive stencil paper, in order to prevent the thermoplastic film from being directly heated by absorbing infrared rays, the film is made as transparent as possible.

If the film is opaque and absorbs electromagnetic waves (such as infrared radiation), perforations may be made in areas other than those corresponding to the low-lightness areas of the original.
This is because the desired and proper plate making cannot be performed.

(c) Problems to be solved by the invention As mentioned above, conventional heat-sensitive stencil paper uses a film that is difficult to absorb (easily transmit) electromagnetic waves.
Even when this heat-sensitive stencil paper was irradiated with a laser beam, the film was not heated by the laser beam, making it impossible to directly make a plate. In other words, in the case of direct plate making using a laser beam, it is necessary to make perforations in the part of the film that is irradiated with the laser beam, but as mentioned above, this film is made of a material that does not easily absorb the laser beam (electromagnetic waves). If the plate is configured in such a way that it is not heated by the laser beam, it is difficult to form a hole, and as a result, proper plate making cannot be performed.

In addition, conventionally well-known opaque stencil paper coated with blue colored paraffin (so-called υ
There are various types of base paper (base paper for clothing) and so-called carbon vapor, but these base papers and heat-sensitive stencil base paper differ in their plate-making method, structure,
Physical properties etc. are significantly different.

The present invention has been made in view of the problems of the prior art, and aims to realize a thermal stencil paper that can be directly made into a plate by irradiating it with electromagnetic waves such as a laser beam.

B) Means for Solving the Problems The present invention provides a film in which a film made of a thermoplastic resin containing an electromagnetic wave absorbing substance and a support made of a porous member are attached. It is a heat-sensitive stencil paper.

(e) Effect In the present invention, since the film on which the perforations are formed contains an electromagnetic wave absorbing substance such as graphite, when the film is irradiated with electromagnetic waves along the shape of the original image, the electromagnetic waves of the film are The irradiated area is heated and a hole corresponding to the original image is opened. Therefore, plate making is performed directly using electromagnetic waves.

(F) Embodiment FIG. 1 is a partially enlarged cross-sectional view showing an embodiment of the present invention, and FIG. 2 is a schematic diagram showing the construction of a laser plate-making apparatus for plate-making a base paper according to the embodiment of the present invention. Further, FIG. 3 is a block diagram showing a control section of the laser plate making apparatus.

In FIG. 1, (1) is a conventionally known support in the form of a sheet made of natural fibers such as manila hemp or chemical fibers such as fine denier and having a thickness of 20 μm to 50 μm. A film (2) made of a conventionally known thermoplastic material such as a copolymer of vinylidene chloride and vinyl chloride, polypropylene, polyethylene, or polyester is attached to the side surface of the support (1), A heat-sensitive stencil paper (3) is constructed. In addition, the film (2)
contains ultrafine powders such as graphite and various pigments as electromagnetic wave absorbing substances. Further, the film (2) is stretched and formed to have a thickness of 1 μm to 6 μm so that perforations can be easily created using a laser beam.

Next, a laser plate making apparatus for directly making a plate by irradiating the base paper (3) of this embodiment with a laser beam will be described with reference to FIGS. 2 and 3.

In FIG. 2, (4) is the first cylindrical body around which the original (6) is wrapped, and (5) is the heat-sensitive stencil paper (3).
is the second cylindrical body around which is wound. Said double cylinder body (4)
(5) are integrally connected at the center, and both cylinder bodies (4H5) are configured to be integrally rotated by a motor (not shown). (The force is a rotating shaft that is held at both ends by the chassis (10) and passes through both the cylinder bodies (4) and (5). Also, (8) is a setper that holds both ends of the original (6). , (9) are set bars that hold both ends of the base paper (3).

On the sides of the first and second cylindrical bodies (4) and (5), there are l provided extending parallel to the rotation axes of these cylindrical bodies (4) and (5).
A pair of guide bars αηα are arranged in parallel, and a YAG (yttrium aluminum garnet) laser oscillator α1 is slidably mounted on the guide bars 01)(2). A well-known pickup head α→ for optically reading the original (6) is fixedly installed near the right end of the laser oscillator α opening.

Note that the laser head αQ that emits the laser beam is located near the left end of the laser oscillator a3, and the distance between this head 0υ and the pickup head 0→ is the original (
The distance is set to be equal to the distance from one end (left end) of base paper (3) to one end (left end) of base paper (3).

Next, the operation of the laser engraving apparatus will be explained. The first and second cylindrical bodies (41 (5) are integrally 300 mm
Rotates (main scan) with r, p, m, and at the same time laser oscillator α
(2) moves in the right direction at a constant speed (0,171EIg/sec) (sub-scanning with respect to the second cylinder (5)), but at this time, the pink-up head α→ is fixedly installed on the laser oscillator α pier. Therefore, this pickup head Q→ also moves in the same direction and at the same speed as the laser head α0 (sub-scanning with respect to the first cylindrical body (4)). Then, the optical signal read from the original (6) is converted into an electrical signal by the pickup head a→, and this electrical signal is A/D converted by the light intensity detector H, and then input to the microcomputer αη to provide information. It is processed. The output signal from the microcomputer αη is input to the laser modulator α, and the laser head α0
The output of the laser beam emitted from the is controlled. When the heat-sensitive stencil paper (3) is selectively irradiated with the laser beam emitted from the laser head α, the portion of the film (2) (see Figure 1) that is irradiated with the laser beam as described above. A perforation is made in the hole, and an image corresponding to the original image is made on the heat-sensitive stencil paper (3).

In addition, in this device, the oscillation wavelength is 106 as the electromagnetic wave generation source.
Using a 0OA YAG laser oscillator, the image density is 30
Although this setting is made in this example, a semiconductor laser oscillator may be used instead of the YAG laser oscillator, and it is still possible to further increase the image density.

When the heat-sensitive stencil paper (3) prepared as described above was used for printing on a Seiki Kogyo rotary copying press (Warp 1J5000), it was possible to obtain fine prints with extremely high printing quality.

(G) Effects of the Invention In the present invention, since the film in which the perforations are made contains an electromagnetic wave absorbing substance, it is possible to directly plate a heat-sensitive stencil paper using electromagnetic waves, which was previously considered impossible. Therefore, since laser plate making is possible, highly advanced plate making technology can be utilized.

In addition, by using a laser oscillator, the laser beam output of the laser printer can be directly supplied to the plate-making device, so it is possible to improve plate-making efficiency and dramatically expand the uses of thermal stencil paper. .

[Brief explanation of the drawing]

FIG. 1 is a partially enlarged sectional view showing one embodiment of the present invention, and FIG.
The figure is a schematic configuration diagram of the laser engraving apparatus, and FIG. 3 is a block diagram. (1) Support, (2) Film, (3)
・Thermal stencil paper.

Claims (1)

[Scope of Claims] 1. A heat-sensitive stencil paper comprising a film made of a thermoplastic resin containing an electromagnetic wave absorbing substance and a support made of a porous member attached to each other. 2. The heat-sensitive stencil paper according to claim 1, wherein the film is made of a stretchable resin. 3. The heat-sensitive stencil paper according to claim 1 or 2, wherein the electromagnetic wave absorbing substance is graphite.