JPH059167Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a stencil-making device for stencil printing.

Stencil printing is relatively simple and inexpensive among printing methods, so it is used for printing flyers, pamphlets, etc. This stencil printing uses a stencil printing master in which the image to be printed is formed by ink-permeable through holes.Printing ink is applied to the master plate with printing paper superimposed on the master, and the printing ink is applied to the through holes. In this method, a printed image is formed by passing the liquid through the paper and adhering it to the printing paper.

In the conventional method of manufacturing a stencil printing master,
As shown in FIG. 4, a heat-sensitive layer 1 made of synthetic resin
The original surface of the original 2 to be copied is brought into close contact with the surface of the heat-sensitive layer 11 of a light-transmissive stencil 1 made of a laminate of 1 and a porous support 12 into which printing ink permeates. Light including infrared IR from a flash discharge lamp is irradiated onto the document surface of the document 2 through the stencil 1, and the image portion 21 in the heat-sensitive layer 11 is heated by the heat generated by the infrared absorption in the black image portion 21 of the document 2, for example. An ink-permeable through hole 13 is formed in a portion facing the stencil plate, and a stencil printing original plate 10 is manufactured as shown in FIG.

Incidentally, the stencil 1 is often integrated with the mount 3 as shown in FIG. It is held in between. This holding prevents the original 2 from shifting its position, and furthermore, when arranging multiple small-sized originals 2 to form a new original, the mount 3
It would be convenient if it were integrated with the mount 3.
is not necessarily necessary.

By the way, in order to obtain a clear and faithful printed image, the degree of adhesion between the stencil 1 and the document 2 is important, and the heat generated in the image area 21 is reliably transferred to the heat-sensitive layer 11 to ensure that the image area 21 is faithfully printed. Through hole 13
must be formed. This stencil 1
In order to bring the stencil 1 and original 2 into close contact with each other, a belt is wrapped around a rotatable cylindrical transparent body and stretched, and the set of stencil 1 and original 2 is held between the belt and the transparent body. Since both are in surface contact, it is difficult to bring them into uniform surface contact. Therefore, when the image portion 21 consists of characters or figures mainly consisting of lines, it can be reproduced relatively faithfully, but when the image portion 21 is composed of a large area, such as a "solid black part" or a halftone part of a photograph, for example. If it is, there will be areas where the adhesion is insufficient, resulting in a defect called "white spots" in the printed image. As a countermeasure for this defect, it has been proposed to increase the tension of the belt to increase the clamping pressure with the transparent body. However, the transparent body is not a perfect cylinder, and when the cylinder is pulled out and manufactured, the unevenness of the cutting die is transferred to the transparent body, resulting in unevenness on the surface. On the other hand, since belts are made of hard cloth with high tensile strength, increasing the tension of the belt causes the convex parts of the transparent body to adhere strongly, but in the concave parts, the hard belt adapts to the concave parts and does not deform. Therefore, there is no close contact in this part, and for this reason, even if the tension is increased, there is a limit to uniform surface contact, and sufficient results are not obtained.

In addition, if the contact surface is flat, such as in a photo positive contact printer, attaching an elastic sheet such as urethane foam with air bubbles to the surface of the pressing plate and pressing it is effective for uniform surface contact. . However, in the case of a plate-making device for stencil printing, the transparent body is cylindrical, so when a thick elastic sheet is attached to the surface of the belt and pressed against the transparent body, the elastic sheet forms a circular shape along the transparent body. transforms into Since the elastic sheet is thick, the surface of the elastic sheet is compressed in the circumferential direction, causing wrinkles.
occurs. For this reason, it is not effective in uniformly bringing the document and the stencil into close contact with each other.

Therefore, the present invention was developed for use in stencil printing, where the original and the stencil are in uniform surface contact, and an original with no "white spots" or defects can be obtained even when the original has many "solid black parts" such as photographs or halftones. The purpose is to provide plate making equipment. For this purpose, a wide endless belt is stretched around a rotatable cylindrical transparent body, multiple fixed rollers, and a tension roller, and the set of original and stencil is sandwiched between the belt and the transparent body. In a plate-making device that is held under pressure and irradiates light including infrared rays toward the stencil through a transparent body, the endless belt is
This is achieved by a plate-making device for stencil printing characterized in that highly elastic hair-like bodies are flocked on the surface of the interlining of the belt, and the flocked surface is in contact with a transparent body.

The present invention will be specifically described below based on embodiments shown in the drawings.

In FIG. 1, a glass cylindrical transparent body 4 is rotatably mounted in the apparatus, and a flash discharge lamp 41 as an infrared radiation source and a mirror 42 surrounding the flash discharge lamp 41 are arranged inside the body. A wide endless belt 5 is wound around the three fixed rollers 6, one tension roller 7, and the transparent body 4, and the tension roller 7 is biased by the elastic force of the tension spring 9. Therefore, the belt 5 is stretched under tension. One of the fixed rollers 6 is a driving roller, and as the roller rotates, the belt 5 comes into pressure contact with the surface of the transparent body 4 and runs while rotating together with the transparent body 4. Near the transparent body 4, a carry-in chute 81 and a carry-out chute 82 are provided in two stages, upper and lower. When a combination W of a document 2 and a stencil 1 is inputted from the carry-in chute 81, the combination W is sandwiched between the transparent body 4 and the belt 5. During this time, it is irradiated with light including infrared rays by the flash of the flash discharge lamp 41, and is taken out from the carry-out chute 82.

As shown in FIG. 2, the endless belt 5 has a hard fabric interlining 51 that has a large tensile strength and hardly undergoes elongation deformation, and has a hair-like body 52 with high elasticity like soft rubber on the surface of the interlining 51. Highly densely flocked. The thickness of the hair-like bodies 52 can be arbitrarily selected from a wide range, but the point is that the hair-like bodies 52 that spring back against compressive force each independently protrude from the interlining 51. Bye. The flocked surface is wrapped around the transparent body 4 so as to be in contact with the surface thereof. Therefore, the belt 5 and the transparent body 4
When the combination W of the original 2 and the stencil 1 is clamped between the two, as shown in FIG. Press W, but especially the hair-like body 52
Since each one is independent, the recess 4
To surely bring a document 2 and a stencil 1 into close contact regardless of the shape of a. Therefore, any recess 4a can be reliably brought into close contact without unnecessarily increasing the tension of the belt 5, and the original 2 and the stencil 1 are brought into uniform surface contact.

Therefore, when the original 2 and the stencil 1 are irradiated with light including infrared rays, the heat generated in the wide area image area 21 is reliably transferred to the heat-sensitive layer 11, as explained in FIGS. 4 and 5. Then, a through hole 13 that is faithful to the image portion 21 is formed. Therefore, even if the document has many "solid black parts" such as photographs or halftones, "white spots" defects will not occur, and a clear printed image can be obtained.

As explained above, the endless belt has highly elastic hair-like flocks on the surface of the interlining of the belt, and the flocked surface is in contact with the transparent body, so that the original and the stencil are evenly placed on the same surface. It is possible to provide a plate-making device for stencil printing that can obtain an original plate that adheres closely and is free of "white spots" defects.

[Brief explanation of the drawing]

Figure 1 is a side view of the embodiment of the present invention, Figures 2 and 3 are
The figures are also cross-sectional views of the main parts, Figures 4, 5, and 6.
The figure is an explanatory cross-sectional view of the original plate. DESCRIPTION OF SYMBOLS 1... Stencil, 10... Original plate, 11... Heat sensitive layer, 12... Porous support, 2... Original, 4...
... Transparent body, 41 ... Flash discharge lamp, 42 ... Mirror, 5 ... Endless belt, 51 ... Interlining, 5
2...hairy body, 6...fixed roller, 7...tension roller, 9...tension spring.

Claims (1)

[Scope of utility model registration request] A wide endless belt is stretched around a rotatable cylindrical transparent body, multiple fixed rollers, and a tension roller, and the set of document and stencil is held between the belt and the transparent body. In a plate-making device that irradiates light including infrared rays toward a stencil through a transparent body, the endless belt has highly elastic hair-like flocks on the surface of the interlining of the belt, and this flocked surface is attached to the transparent body. A plate-making device for stencil printing, characterized in that it is in contact with the stencil.