JPH0811278A - Manufacturing device for lithography - Google Patents

Abstract

PURPOSE:To favorably manufacture a large lithography by making a recording width of a thermal head large-sized by a method wherein a plurality of thermal printing heads are arranged by putting a ridge-line of a roll between them, and one thermal head is shifted by an integral number of times for a length between heating elements in an axial directional of the roll to the other thermal head. CONSTITUTION:A roll revolving means revolving a roll 1 by using its axial line as a center, and a contact means which brings heating parts 3A, 3B of thermal printing heads 2A, 2B into contact with the roll to which a plate material 4 is fitted, are provided. Then, a memory means which stores a data of each pixel of the plate material 4, and a dividing means which divides the data of the memory means respectively into the thermal printing heads 2A, 2B, are provided. Further, a plurality of the thermal printing heads 2A, 2B are arranged by putting a ridgeline of the roll between them in parallel with each other. One thermal printing head is arranged by being shifted in an axial direction of the roll 1 by an integral number of times for a length between adjacent heating elements to the other thermal printing head.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manufacturing apparatus for manufacturing a heat sensitive lithographic plate using a thermal print head.

[0002]

2. Description of the Related Art Printing plates are roughly classified into letterpress, planographic,
Although intaglio and stencil (screen) are provided, lithographic printing is generally performed by offset printing, and is performed as follows. That is, the planographic printing plate has a pattern of hydrophilic portions and lipophilic portions formed on its surface (printing surface), and is wound around a roll provided in the offset printing machine main body. Then, when the immersing water and the printing ink are alternately supplied to the lithographic surface, the immersing water adheres to the hydrophilic portion, while the printing ink repels the immersing water and adheres only to the lipophilic portion, This printing ink is once transferred to a blanket rubber roll and then retransferred to a paper or the like which is a printing medium.

Here, a conventional so-called lithographic manufacturing apparatus is mainly in a system called a silver salt system or an OPC system. In the silver salt method, a plate material substrate formed by coating a hydrophilic base material with a photosensitive solution is image-exposed through a photographic printing paper original or a film-baked material, which is developed and then dried to produce a lithographic plate. In recent years, the plate making process is omitted, and the laser beam is directly scanned using the digital data from the DTP without passing through the photographic printing paper original or a film-baked product of the printing paper original to obtain an image. An exposure type apparatus has also been put into practical use. On the other hand, the OPC method is
In this method, a plate material having an optical semiconductor on its surface is imagewise exposed to form a charging pattern, which is developed with a lipophilic toner and then fixed to produce a lithographic plate.

All of these systems are optical manufacturing systems for exposing a plate material to images, and the printing quality depends on the original image used and the diameter of the laser beam, but in general it is compared with other systems. High quality printing is obtained.

[0005]

However, the manufacturing process of the optical manufacturing apparatus is complicated as described above, and
In order to efficiently carry out the manufacturing work, a series of steps such as image exposure, development, and drying are automated by one device, which has the drawback that the entire manufacturing device is large and expensive. . In addition, such a device has a drawback that waste liquid is generated in the developing process, and therefore the treatment must be performed. Therefore, in recent years, the process is simple and space saving is required. It is desired to provide an inexpensive device.

On the other hand, for example, Japanese Patent Laid-Open No. 1-1684
No. 50 or JP-A-1-209135, D
A thermal-sensitive manufacturing apparatus has been disclosed in which digital data from TP is directly used to form a print pattern on a plate material by a thermal print head. According to these publications, by utilizing the thermal transfer method, a planographic printing plate can be easily manufactured by using an existing personal computer, word processor or the like as an output device.
However, since the line type thermal print head used in the thermal type manufacturing apparatus is mainly manufactured for OA equipment such as a facsimile, most of the maximum recording width of the thermal print head is A3 size (29 mm).
7 mm). However, lithographic printing requires A0 size and A1 size, and the recording width is insufficient if the conventional thermal print head is used as it is for the production of the lithographic plate.

On the other hand, in devices such as plotters, the problem of the recording width of the thermal print heads described above is solved by connecting a plurality of thermal print heads in the longitudinal direction thereof. It is technically difficult to eliminate the positional alignment and the height difference of the connected portions, and it takes a lot of man-hours, so that the connected thermal print head becomes expensive. In addition, the connected thermal print head cannot replace only the thermal print head having the defective heating element when a failure of the heating element occurs in one of the plurality of thermal print heads. As a result, the connected thermal print heads will be replaced, which is not preferable in terms of cost. Further, the printed quality of the connected thermal print head is deteriorated at the connected portion, and therefore, at present, it is desired to provide an apparatus which replaces the connected thermal print head.

The present invention is capable of solving the above-mentioned problems, and an object thereof is to increase the recording width of a thermal print head by an inexpensive and simple apparatus structure, thereby producing a large lithographic plate. An object of the present invention is to provide a lithographic manufacturing apparatus that can be preferably implemented.

[0009]

In the apparatus for producing a lithographic plate of the present invention, the surface of a lithographic plate material is heated to change the surface of the plate material from hydrophilic to lipophilic to form a printing pattern. In the lithographic plate manufacturing apparatus, a roll on which the plate material is mounted, a plurality of thermal print heads each having a heating element having a heating element that heats the plate material corresponding to each pixel, and the roll having the axis line Roll rotating means for rotating about the center, contact means for contacting the heat generating portion of the thermal print head and the roll on which the plate material is mounted, storage means for storing data of each pixel of the plate material,
Dividing means for dividing the data in the storage means into a plurality of pieces for each of the thermal print heads, and the plurality of thermal print heads are arranged in parallel to each other at least on both sides of the ridgeline of the roll. Another thermal print head is offset from one thermal print head in the axial direction of the roll by an integral multiple of the length between the adjacent heating elements.

[0010]

According to the lithographic plate manufacturing apparatus of the present invention, the roll on which the lithographic plate material is mounted and the heat generating portions of the plurality of thermal print heads are brought into contact with each other by contact means such as a reversible motor, and, for example, pulsed. The roll is rotated by a roll rotating means such as a motor. Then, each heating element that constitutes the heating portion of the thermal print head is selectively heated based on the data of the storage unit, and image formation is performed on the plate material. The thermal print heads are arranged at least on both sides of the ridgeline, and the other thermal print heads are displaced in the axial direction of the roll by an integral multiple of the length between adjacent heating elements. Therefore, particularly when the heating element near the left end of one thermal print head and the heating element near the right end of the other thermal print head are aligned in the tangential direction of the roll, the length is substantially several times less. A thermal printhead will be constructed. Therefore, by dividing the data in the storage means by the dividing means for each thermal print head and transferring it, it is possible to preferably manufacture a large-sized plate material.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 to 4 are views showing an embodiment of an apparatus for producing a lithographic plate (hereinafter, simply referred to as an apparatus) according to the present invention, and FIG. 1 is an enlarged plan view of an essential part of a thermal print head constituting the apparatus, 2 and 3 are side and front views showing the mechanical structure of the apparatus, and FIG. 4 is a block diagram showing the basic structure of the drive unit of the apparatus.

The apparatus shown in FIGS. 2 and 3 is of a circular pressure type in this example. That is, the roll indicated by 1 is
The surface of a cylindrical body made of metal is coated with, for example, a layer of silicon rubber or the like, and can be rotated at a constant peripheral speed in the direction of arrow X about its axis by a pulse motor (not shown) or the like as roll rotation means. And in parallel with the arrow Y direction by a reversible motor (not shown) as a contact means.

Further, a pair of line type thermal print heads indicated by reference numerals 2A and 2B are individually configured, and a plurality of (for example, 1536) heating elements 3a ..., 3b.
Are connected in series to form one line of the heat generating portions 3A and 3B, and each of the heat generating elements 3a ..., 3b has a shift register corresponding to each of the heat generating elements 3a. For example, it is designed to be divided into 512 parts, each of which is driven by a driver IC (not shown). The pair of thermal print heads 2A,
2B are arranged on both sides in parallel with each other with the lower end ridgeline of the roll 1 sandwiched therebetween, and one of the thermal print heads 2B is arranged in the axial direction of the roll 1 with respect to the other thermal print head 2A. They are arranged so as to be offset by a predetermined distance.

In this example, when the unit corresponding to one of the heating elements 3a, 3b, ... which composes the heating portions 3A, 3B is one dot, the predetermined distance is one thermal print head 2A. On the other hand, the other thermal print head 2B has a length shifted by several dots. Therefore, particularly in this example, as shown in FIG. 1, the three heating elements 3a on the left end side of the one thermal print head 2A are provided.
And the three heat generating elements 3b on the right end side of the other thermal print head 2B are aligned in the tangential direction of the roll 1, whereby both thermal print heads 2A and 2B are positioned relative to the roll 1. It is constructed to be a little less than twice as long.

On the other hand, a plate material 4 serving as a planographic plate is fixed to the surface of the roll 1. The plate material 4 has the following composition components in this example. 1) Hydrophilic polymer: P-1 (15% solid content); 12.0 parts by weight 2) Lipophilic microcapsule: M-1 (20% solid content); 6.0 parts by weight 3) Isobutyronitrile; 1.0 parts by weight 4) Calcium carbonate; 0.8 parts by weight 5) Zinc stearate; 0.5 parts by weight 6) Water; 18.7 parts by weight Here, the lipophilic polymer: P-1 is as follows. Is formed in. First, hydroxylethyl acrylate 5.8
g, 16.0 g of acrylic acid, 0.2 g of dodecyl mercaptan, and 100 g of isopropyl alcohol were heated to 70 ° C. with stirring, and then 2,2
-Adding 0.38 g of azobis and reacting for 4 hours, further adding 6.4 g of glycidyl methacrylate, 0.5 g of t-butylhydroquinone and 1 g of benzyltrimethylammonium chloride and reacting at 130 ° C for 6 hours, Then, a poor solvent is added to carry out precipitation, washing and purification to obtain a lipophilic polymer: P-1.

Microcapsules M-1 are polyisocyanate compound 10 g obtained by desolvating Coronate L to a solid state, ethyl alcohol 8 g, and purified water 2 g.
And 5% aqueous solution of polyacrylamide are placed in a container and stirred at room temperature for 1 hour to obtain isocyanate microcapsules. And plate material 4
Is the above-mentioned respective components 1) to 6) applied onto a polyester support having a thickness of 180 μm coated with a urethane-based adhesive, further dried, and reacted at about 40 ° C. for 4 hours. It was made. More specifically, the lipophilic component is microencapsulated and disposed between lipophilic polymers, and the microcapsules are destroyed by the heat generated by the heat generating portion of the thermal print head 2, and the lipophilic pattern is formed on the destroyed portion of the microcapsules. Is created.

The roll 1 and the thermal print heads 2A and 2B are the same as the thermal print head 2A.
The heat generating portion and the ridge edge 1a of the roll 1 and the heat generating portion of the thermal print head 2B and the ridge edge 1b of the roll 1 are arranged in a main body (not shown) at a position where they overlap. When forming a printing pattern on the plate material 4,
The roll 1 is moved vertically downward to bring the printing surface of the plate material 4 into contact with the heat generating portions of the thermal print heads 2A and 2B at a predetermined pressure, and the roll 1 in this state is rotated to print in the sub-scanning direction. The material 4 is conveyed, and at this time, the heating elements 3a, 3b, ... Of the thermal print heads 2A, 2B are selectively heated by a drive unit described later.

The drive unit of the apparatus shown in FIG. 4 is constructed as follows. That is, the page memory as a storage unit denoted by reference numeral 5 stores pixel data for one page of paper or the like to be printed, and this pixel data is sequentially output by the address generation unit denoted by reference numeral 7. The data is designated and read, and is sent to the data dividing unit as a dividing unit indicated by reference numeral 6. Then, the signal specifying the pixel by the address generating unit 7 is also sent to the data dividing unit 6 at the same time, and the data dividing unit 6 transfers the pixel data to the thermal print heads 2A and 2B according to the specifying signal. Divide and send to each.

Next, the operation of the device having the above structure will be described. In this example, the thermal print heads 2A and 2B of 200 dpi are used, and the total number of heat generating elements of each of the thermal print heads 2A and 2B is 1536.
One line consisting of 3 pieces is divided into 3 parts, and 1 per division
3 data input lines using 6 data input lines
Data of two pixels is transferred. The reason why the heat generating parts 3A and 3B are divided into three is that the heat generating parts 3A and 3B are
The heating elements 3a ..., 3b ... of 3B generate heat in order from No. 1 to No. 1536, and therefore the heating elements 3a .., 3b from No. 1 to 512 belonging to the first division line.
It is sufficient to heat only the first divided line when sequentially generating heat in order to generate heat, and the electric power for heat generation is higher than that in the case where all the one line is generated by dividing one line in this way. The reason is that the amount is not excessively consumed.

First, a reversible motor is driven to drive a roll 2 on which a plate material 4 to be a lithographic plate is mounted, and a heat generating portion 3 of a pair of thermal print heads 2A and 2B.
The roll 2 is rotated by a pulse motor while being pressed against A and 3B. At this time, a signal corresponding to the gradation data for one page of paper is sent from the page memory 5, and this signal is divided by the data dividing section 6 in correspondence with each of the thermal print heads 2A and 2B. Later transferred to these.

On the basis of this signal, the heat generating elements 3a, 3b ... Which constitute the heat generating portions 3A, 3B of the thermal print heads 2A, 2B are selectively heated, and an image is formed on the plate material 4. At this time, each thermal print head 2A,
2B includes three heating elements 3a on the left end side of one thermal print head 2A, and three heating elements 3b on the right end side of the other thermal print head 2B.
Since it is in the state of being aligned with the tangential direction of
The length of the thermal print head for
It is almost double. As a result, even a plate material 4 having a large size (specifically, A0 size, A1 size, etc.) can be manufactured without lowering print quality.

Further, according to such an apparatus, since the thermal printing heads 2A and 2B are simply used for manufacturing the plate material 4, the cost of the entire apparatus is low and the maintenance is easy. be able to. Further, since the development waste liquid is not generated during the production of the lithographic plate as in the conventional case, the waste liquid treatment step can be omitted and the pollution problem can be solved.

In this embodiment, two thermal print heads are used, but three, four, ... Can be used. The number of thermal print heads is the size of the planographic plate to be manufactured. It may be determined as appropriate in accordance with. Further, in both thermal print heads 2A and 2B, the three heating elements 3a on the left end side of one thermal print head 2A and the other thermal print head 2B
A case where the three heating elements 3b on the right end side of the above are aligned in the tangential direction of the roll 1, that is, the thermal print head 2B is displaced by 1533 dots (= 1536-3 dots) from the thermal print head 2A will be described. However, other lengths are of course possible.

[0024]

As is apparent from the above description, according to the lithographic plate manufacturing apparatus of the present invention, the thermal print head can be made large in size by an inexpensive and simple apparatus configuration, and thus, the lithographic plate having a large size can be manufactured. Manufacturing can be realized. Further, since the thermal print head is used as the heating means, the cost of the entire apparatus is low and maintenance can be facilitated. Further, since the developing waste liquid is not generated during the production of the planographic printing plate, the waste liquid treatment step can be omitted and the pollution problem can be solved.

[Brief description of drawings]

FIG. 1 is an enlarged plan view of an essential part of a thermal print head that constitutes a lithographic plate manufacturing apparatus according to the present invention.

FIG. 2 is a side view showing a mechanical configuration of the device.

FIG. 3 is a front view of the same.

FIG. 4 is a block diagram showing a basic configuration of a drive unit of the device.

[Explanation of symbols]

 1 roll 2A, 2B thermal print head 3A, 3B heat generating part 3a, 3b heat generating element 4 plate material 5 page memory (storing means) 6 data dividing section (dividing means)

Claims (1)

[Claims] 1. A lithographic plate manufacturing apparatus which heats the surface of a lithographic printing plate to change the surface of the lithographic printing plate from hydrophilic to lipophilic to form a printing pattern. A plurality of rolls, a plurality of thermal print heads each having a heating portion having a heating element that heats the plate material corresponding to each pixel, roll rotating means for rotating the rolls about their axes, and the thermal print Contact means for contacting the heat generating portion of the head with the roll on which the plate material is mounted, storage means for storing data of each pixel of the plate material, and a plurality of data of the storage means for each of the thermal print heads. And a plurality of thermal print heads are arranged in parallel with each other at least on both sides of the ridgeline of the roll, and one thermal print head is provided. An apparatus for manufacturing a lithographic plate, wherein another thermal print head is displaced from the print head in the axial direction of the roll by an integral multiple of the length between the adjacent heating elements.