JPH08216359A - Processing device - Google Patents

Abstract

PURPOSE: To process a screen process base paper on which moires are not conspicuous by using a screen process base paper constituted of a grating as a supporter. CONSTITUTION: A screen processing base paper 4 consisting of a grating and a solvent-soluble resin layer is stuck on a rectangular outer frame 4a. The grating direction of a screen processing base paper 4 conforms to the direction of respective sides of the rectangular outer frame 4a. An image information from an image scanner 1 is image-processed by a personal computer 2 so that the image is rotated by the given angle. The processed image information is outputted to a processing section 3. A discharge section 6 of the processing section 3 is provided with a number of jet nozzles for jetting a solvent and transferred in the processing direction A crossing the parallel direction of the jet nozzles. The processing direction A is inclined by the given angle to the grating direction of the screen processing base paper 4. The processing section 3 is driven by a processed image information. An image before the rotation is bored on the screen processing base paper 4. The ratio between the resolution in the main scanning and sub-scanning of the processing section 3 and the grating interval of the screen processing base paper 4 is varied in an analogic manner at all times. A bored image without generating interference is processed, and a preferred screen process printed image without generating moires is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate making apparatus for making a stencil sheet having a plate-making layer formed on a grid-like support, and more particularly to a plate making apparatus capable of forming a perforated image in which moire fringes are not noticeable. Is.

[0002]

2. Description of the Related Art Generally, a stencil sheet has a structure in which a plate-making layer is provided on a porous support and is stretched on an outer frame for use. Japanese paper or a lattice is known as a support. When the lattice is used as the support, the lattice is generally attached so that the lattice direction and the directions of the sides of the rectangular outer frame are aligned with each other. As the plate-making layer, a material such as a heat-sensitive film which can be perforated by heat is known.

As a method for making such a stencil sheet, for example, a method using a plate making apparatus having a thermal head is known. The thermal head has a large number of heating elements arranged in the main scanning direction at fixed fixed intervals. At the time of plate making, the lattice direction of the support of the stencil sheet and the main scanning direction and the sub scanning direction of the thermal head are aligned,
While moving the thermal head and the stencil sheet relatively in the sub-scanning direction, each heating element is selectively heated to heat-sensitize the stencil sheet.

[0004]

When making a stencil sheet having a lattice as a support, the main scanning direction and the sub-scanning direction of the thermal head of the plate making apparatus are in the same direction as the lattice of the stencil sheet. Therefore, the perforations formed in the stencil sheet by the heating elements of the thermal head arranged at a predetermined interval along the main scanning direction and the sub-scanning direction interfere with the lattice of the stencil sheet having a predetermined lattice constant to cause moire. May occur, and the printed image may have periodic shading, which may cause deterioration of the image. This moire becomes more noticeable as the resolution in the main scanning direction and the sub scanning direction of the plate making apparatus and the lattice constant of the stencil sheet become closer to an integer ratio. As a measure against moire, it is possible to use Japanese paper instead of a grid for the support of the stencil paper, but Japanese paper has a problem that it is inferior in durability to the grid.

It is an object of the present invention to provide a plate making apparatus capable of forming an image in which moire is inconspicuous by using a stencil sheet having a lattice as a support.

[0006]

A plate making apparatus according to claim 1 is a plate making apparatus for making a stencil sheet having a plate-making layer formed on a lattice-shaped support, and the main scanning direction at the time of plate making. And the sub-scanning direction is inclined at a predetermined angle with respect to the direction of the grid of the stencil sheet, and has a plate making means for inputting image information subjected to image processing.

A plate making apparatus according to a second aspect is a plate making apparatus for making a stencil sheet on which a plate making layer is formed on a lattice-shaped support, and the main scanning direction and the sub scanning direction at the time of plate making are the above-mentioned. The stencil sheet is characterized by being provided with a plate making means which is inclined by a predetermined angle with respect to the direction of the grid and which receives image information which has undergone image processing for rotating the image by a predetermined angle.

A plate making apparatus according to a third aspect is a plate making apparatus for making a stencil sheet on which a plate making layer is formed on a lattice-shaped support, and the main scanning direction and the sub-scanning direction at the time of plate making are the above-mentioned. The stencil sheet is characterized by having a plate making means inclined by a predetermined angle with respect to the direction of the grid of the stencil sheet, and an image processing means for outputting image information obtained by performing image processing for rotating the image by a predetermined angle to the plate making means.

A plate making apparatus according to a fourth aspect is the plate making apparatus according to the third aspect, characterized in that the plate making means is a non-contact type plate making means that does not come into contact with the stencil sheet.

The plate making apparatus according to a fifth aspect is the plate making apparatus according to the fourth aspect, wherein the predetermined angle is 45 °.

[0011]

In the image processing means, the image information is subjected to image processing for rotating the image by a predetermined angle. The image information subjected to the image processing is output from the image processing means to the plate making means.
The main scanning direction and the sub scanning direction of the plate making means are inclined at a predetermined angle with respect to the direction of the grid of the stencil sheet for plate making. The plate making means punches an image at a predetermined position of the stencil sheet without causing moire.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a plate making apparatus according to the present invention will be described below with reference to the drawings. First, the stencil sheet 4 used in this embodiment will be described. The stencil sheet 4 used in this embodiment has a structure in which a lattice as a support is provided with a solvent-soluble resin layer as a plate-making layer. The solvent-soluble resin layer contains, as a main resin component, a thermoplastic resin or a thermosetting resin that is soluble in a solvent such as water or an organic solvent. As shown in FIG. 1, the stencil sheet 4 is attached to a rectangular outer frame 4a, but its lattice direction and the rectangular outer frame 4a.
The direction of each side of is the same.

Examples of the resin component soluble in an organic solvent include polyethylene, polypropylene, isobutylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyvinyl fluoride, polyvinyl acetate, acrylic resin, polyacrylonitrile, polyamide, Polyimide,
Petroleum resin, phenol resin, amino resin, epoxy resin, polyester, polycarbonate, polyurethane,
Polysulfone, silicone resin, alkyd resin, melamine resin, etc. are used. These resin components may be used alone or in combination, or may be used as a copolymer.

The water-soluble resin component is a resin soluble in water or an organic solvent miscible with water, such as polyvinyl alcohol, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, polyvinyl pyrrolidone, polyethylene-polyvinyl alcohol copolymer, polyethylene. Oxide, polyvinyl ether,
Polyvinyl acetal, polyacrylamide, starch, dextrin, alginic acid, ascorbic acid, water-soluble urethane and the like can be used. These resin components may be used alone or in combination, or may be used as a copolymer.

Thickness of the solvent-soluble resin layer d (μm)
Is preferably in the range of 0.1 to 100 μm, and 0.5 to 5
The range of 0 μm is more preferable. If the thickness is less than 0.1 μm, the strength of the solvent-soluble resin layer will be insufficient, resulting in 100 μm.
If it exceeds m, a large amount of solvent or water is required to dissolve the solvent-soluble resin layer, and the dissolution may be insufficient during plate making.

The stencil sheet is, for example, (1) a method of sticking a solvent-soluble resin film and a lattice with an adhesive or a pressure-sensitive adhesive, (2) a method of heat-sealing the solvent-soluble resin film to the lattice, and (3) dissolving in a solvent. Alternatively, a method in which a dispersed resin solution is applied onto a lattice and dried to form a solvent-soluble resin layer,
(4) A resin solution dissolved or dispersed in a solvent is applied and dried on a releasable support to form a resin layer, which is then bonded to a grid and then the releasable support is peeled off. I can.

The adhesive or pressure-sensitive adhesive used when producing the base paper by the above-mentioned laminating method can be a solvent-soluble type, a water-dispersed type or the like which is heat-cured or photo-cured and used. Melt type adhesives may be used.

Specific examples of the adhesive or pressure-sensitive adhesive include
Epoxy resin, phenol resin, polyvinyl acetate, ethylene-vinyl acetate copolymer, vinyl chloride-vinyl acetate copolymer, acrylic resin, polyester, polyurethane,
Styrene-butadiene copolymer, polyisobutylene, isoprene, butyl rubber, polyacrylamide, rosin,
A terpene resin, polystyrene, etc. are mentioned, and if necessary, a curing agent, a softening agent, a tackifier, a filler, etc. are mixed and used.

Solvents that dissolve the solvent-soluble resin layer include aliphatic hydrocarbons, aromatic hydrocarbons, alcohols, ketones, esters, ethers, aldehydes, carboxylic acids, amines, and low molecular weight compounds. Heterocyclic compounds, oxides, water and the like can be mentioned, for example, hexane, heptane, octane, benzene, toluene, xylene, methyl alcohol, ethyl alcohol, isopropyl alcohol, n-propyl alcohol, butyl alcohol, ethylene glycol, diethylene glycol, propylene glycol. , Glycerin, acetone, methyl ethyl ketone, ethyl acetate, propyl acetate, ethyl ether, tetrahydrofuran, 1,4-dioxane, formic acid, acetic acid, propionic acid, formaldehyde, acetaldehyde, methylamine, ethylenedi Min, dimethylformamide, pyridine, ethylene oxide, and the like. These can be used alone or in combination.

If necessary, the solvent for plate making may contain a dye, a pigment, a filler, a binder, a curing agent, a preservative, a wetting agent, a surfactant, a pH adjusting agent and the like. However, it is preferable that these materials and amounts are such that no solid content remains when the solvent is evaporated or concentrated.

Next, the plate making apparatus 10 of this embodiment for making the stencil sheet 4 will be described. As shown in FIG. 2, the plate making apparatus 10 includes an image scanner 1 for reading an image, a personal computer 2 as an image processing means for processing data of an image read by the image scanner 1, and an image data from the personal computer 2. It has an inkjet printer 3 as a plate making means for making the stencil sheet 4.

The image scanner 1 reads an image to be plate-made and generates image information. The image information shown in FIG. 4A generated by the image scanner 1 is
It is input to the personal computer 2. The image information input to the personal computer 2 is subjected to image processing such that the image is rotated by a predetermined angle as shown in FIG.

The image information processed by the personal computer 2 is
It is output to the inkjet printer 3. As shown in FIG. 3, the inkjet printer 3 includes a base 5 on which the stencil sheet 4 is placed, and an ejecting unit for ejecting the solvent as described above in droplets onto the stencil sheet 4 on the base 5. 6 and 6. The discharge part 6 is provided with a large number of discharge nozzles arranged at predetermined intervals, and can move in a plate-making direction A orthogonal to the direction in which the discharge nozzles are arranged in parallel. The discharge unit 6 intermittently or continuously supplies the solvent to the solvent-soluble resin layer of the stencil sheet 4 in a non-contact state based on the image information supplied from the personal computer 2. The solvent supplied from the discharging unit 6 dissolves the solvent-soluble resin layer of the stencil sheet 4 to perforate it, and the solvent-soluble resin layer dissolved in the solvent permeates and diffuses in the lattice.

The main scanning direction and the sub scanning direction in the ink jet printer 3 correspond to the rotation angle in the image processing in the personal computer 2 with respect to the direction of the lattice of the stencil sheet 4 (that is, the side direction of the outer frame 4a). It is tilted by an angle. Therefore, as shown in FIG. 2C, the inkjet printer 3 driven based on the image-processed image information punches the image before rotation on the stencil sheet 4 inclined by a predetermined angle with respect to the inkjet printer 3. can do.

In the image processing, the angle for rotating the image and the inclination angle in the plate making direction with respect to the stencil sheet 4 may be set so that moire is inconspicuous as much as possible. For example, when the stencil sheet 4 which is made with the angle of 45 ° is used, a preferable stencil printing image in which moire is not noticeable can be obtained.

As described above, according to this embodiment, the stencil sheet 4
On the other hand, the ink jet printer 3 is arranged at a predetermined angle, and image information obtained by rotating the image by the same predetermined angle is given to the ink jet printer 3 for plate making. Therefore, the ratio of the lattice spacing of the stencil sheet 4 to the resolution in the main scanning and sub-scanning directions in the inkjet printer 3 always changes in an analog manner, so that a perforated image without interference can be formed. Then, when stencil printing is performed using the stencil base paper 4 perforated in this way, a preferable stencil printing image free from moire can be obtained.

In the first embodiment described above, the stencil sheet 4 having the solvent-soluble resin layer provided on the lattice was used, and the ink was supplied from the ink jet printer 3 to the stencil sheet 4 in a non-contact manner to carry out plate making. In addition, as a method of making a stencil sheet without contact, a method of making a stencil sheet having a heat-sensitive film on a grid by a semiconductor laser can be used.

However, the principle of plate making in the plate making apparatus of the present invention is not limited to the non-contact type using the solvent in the first embodiment. For example, a thermal head as plate making means may be brought into contact with a stencil sheet having a heat-sensitive film provided in a lattice to heat-perforate the heat-sensitive film. However, in that case, the thermal head and the stencil sheet must be relatively moved in contact with each other at a constant pressure during plate making. If the thermal head, which moves at a predetermined angle with respect to the grid of the stencil paper, comes into contact with the outer frame, which is normally oriented in the same direction as the grid of the stencil paper, at any position, the contact between the thermal head and the stencil paper will not occur. There may be a uniform portion. In order to avoid such an inconvenience and keep the thermal head and the stencil sheet in contact with each other at a constant pressure, the outer frame of the stencil sheet must be outside the moving range of the thermal head. In other words, the stencil sheet in the stencil sheet must be relatively small, or the area of the stencil sheet with respect to the plate-making area must be large.

It is considered that the problem of moiré can be solved even when the direction of the grid of the stencil sheet is preliminarily inclined by a predetermined angle and is attached to the outer frame and the ordinary plate making is performed. Fixing by tilting with respect to the frame is technically complicated and has little practical utility.

[0030]

As described above, according to the plate making apparatus of the present invention, the image information which has been subjected to the image processing for rotating the image by a predetermined angle is given to the plate making means inclined by the predetermined angle with respect to the grid of the stencil sheet. Since the plate-making is performed, the ratio of the lattice spacing of the stencil sheet to the resolution in the main-scanning and sub-scanning directions in the plate-making means always changes in an analog manner, so that a perforated image without interference can be formed. Then, when stencil printing is performed using the stencil sheet perforated in this manner, a preferable stencil printing image free from moire can be obtained.

[Brief description of drawings]

FIG. 1 is a plan view of a stencil sheet used in a first embodiment.

FIG. 2 is a perspective view of the plate making apparatus according to the first embodiment.

FIG. 3 is a perspective view of an inkjet printer in the plate making apparatus according to the first embodiment.

FIG. 4 is a diagram showing a process of image information and a plate making process in the first embodiment.

[Explanation of symbols]

 2 PC as image processing means 3 Inkjet printer as plate making means 4 Stencil sheet 10 Plate making device

Claims (5)

[Claims] 1. A plate making apparatus for making a stencil sheet in which a plate-making layer is formed on a lattice-shaped support, wherein a main scanning direction and a sub-scanning direction at the time of plate making are relative to a lattice direction of the stencil sheet. A plate-making apparatus, which is inclined by a predetermined angle and has plate-making means for inputting image information subjected to image processing. 2. A plate making apparatus for making a stencil sheet in which a plate-making layer is formed on a lattice-shaped support, wherein a main scanning direction and a sub-scanning direction at the time of plate making are relative to a lattice direction of the stencil sheet. A plate making apparatus comprising a plate making means which is inclined by a predetermined angle and into which image information subjected to image processing for rotating an image by a predetermined angle is inputted. 3. A plate making apparatus for making a stencil sheet in which a plate-making layer is formed on a lattice-shaped support, wherein the main scanning direction and the sub-scanning direction at the time of plate making are relative to the lattice direction of the stencil sheet. A plate making apparatus comprising: a plate making means inclined by a predetermined angle and image processing means for outputting image information, which has been subjected to image processing for rotating an image by a predetermined angle, to the plate making means. 4. The plate making apparatus according to claim 3, wherein the plate making unit is a non-contact type plate making unit that does not come into contact with the stencil sheet. 5. The plate making apparatus according to claim 4, wherein the predetermined angle is 45 °.