JPS6360751A - Printing master and production thereof - Google Patents

Abstract

PURPOSE:To enable a master to be made in a very short time without using a process device provided with a lens etc., by a method wherein a thermal transfer material is selectively thermo-transferred on a base so that a printing image is formed directly on the base. CONSTITUTION:A thermal transfer film 31 consists of a transfer base 36 and an image forming material 37. The image forming material 37 spread on the transfer base 36 is selectively thermo-transferred on a base film 35 by a thermal head 34 driven by an external signal 33. On the other hand, the image forming material 37 which was not thermo-transferred remains on the transfer base 36 as it is to be taken up by a taken-up roller 32. A signal for driving the thermal head is externally applied, whereby a computer output etc. is connected directly or alternatively the signal is transmitted through various communication circuits to conduct the direct process of a master. In this manner, the master can be made very easily in a short time.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a printing master used in offset printing, which is characterized in that printing images are formed by total heat transfer, and a method for manufacturing the same.

2. Description of the Related Art In general, when copying about 1 to 10 sheets from an original, dry copying using an electrophotographic method is convenient. In addition, when printing a large number of copies of newspapers, magazines, etc., that is, when making copies of approximately 1,000 pages or more from a manuscript, it is recommended to make copies that utilize all of the general printing methods such as letterpress and offset lithography. is advantageous in terms of cost.

However, in the case of in-house newsletters and printed matter with a small number of copies, that is, when copying about 10 to 1000 copies, there is no suitable printing method that can be easily carried out because of the intermediate number of copies. This is a field called light printing.

In this field of light printing, instead of general letterpress or offset lithographic printing methods, a special printing plate called a flexible master is created, and then this master is used for offset lithographic printing. A method is used to do this. Methods for forming all lines of characters, etc. for printing on the master using photographic methods (hereinafter referred to as plate-making) include the conventional direct plate-making method that uses silver salt, and the electrofax plate-making method that uses electrophotography. was widely used.

In the following, offset lithographic printing using such a master will be briefly explained. FIG. 7 is an oblique view of the master. In FIG. 7, 1 is a one-line portion, and 2 is a non-printing portion. The image area 1 contains lipophilic metal, and the non-image area 2 has hydrophilicity. The image area 1 and the non-image area 2 constitute the surface of the master.

Figures 8 to 14 show the printing process used on Master 4 above. It is a figure for explaining. FIG. 8 shows a schematic sectional view 2 of the master. In FIG. 8, 3 is the pace and l is the master. Is the top 3 base 3 lipophilic? An image area 1 having a hydrophilic property and a non-image area 2 having a hydrophilic property are formed. These drawing area 1, non-printing area 2 and base 3 are master 4.
is formed. FIG. 9 shows how the surface of the master 4 is moistened with dampening water. In FIG. 9, 6 is a dampening water roller, 6 is a dampening water roller 7, and a dampening water 6 consisting of water and a small amount of additives is thinly adhered to the surface of this dampening water roller 5. . Then, by passing the dampening water roller 5 on the surface of the master 4, it becomes hydrophilic. A thin layer of dampening solution 6 is adsorbed onto the surface of the non-image area 2. here,
Since the surface of the image area 1 is lipophilic, the dampening water 6 does not adhere to the surface of the image area 1 even when the dampening water roller 5 passes therethrough. 1st
Figure Q shows how ink is attached to the surface of the master 4. In FIG. 10, an ink roller is shown, and printing ink 8 is coated on the surface of the ink roller 7 in the form of a thin film. The printing ink 8 is made of an oil such as linseed oil as a main component in which a pigment such as carbon blank is completely dispersed. Therefore, when the ink roller 7 passes over the printing area 1, which is a lipophilic part, the printing ink St is applied to the printing area 11.

- Ten thousand, is the ink roller 7 hydrophilic? When the stamp ink 8 passes over the non-image area 2, which is the part where the stamp ink 8
does not adhere. Figure 11 shows the state after printing ink 8 is attached to the surface of master 4. It shows. 11th
In the figure, is the printing ink 8 lipophilic as mentioned above?
It adheres only on the image area 1, which has a hydrophilic property, and does not adhere to the non-image area 2, which is defined as hydrophilic. Figure 12 shows the mask-
4 shows the situation when printing ink 8 is transferred to one blanket. In Fig. 12, numeral 9 is a plunket cylinder, on the surface of which is completely wrapped a rubber plate called a blanket. In FIG. 12, the printing ink 8 adhering to the printing area 1 of the master 4 is transferred to the entrance surface of the blank gutter 9. In FIG.

FIG. 13 shows the printing ink 8 on the surface of the blank book 90. Fig. 14 shows how the printing ink 8 is transferred onto the paper from the blanket fence 9? show. In FIG. 14, 1o is paper and 11 is an impression cylinder. That is,
Paper 10' between the plunket cylinder 9 and the pressure 111ii111
, (By passing it through, the blue printing ink attached to the surface of the sld paper 10 is transferred to the surface 1 of the sld paper 10. At this time, the pressure 11 is applied to the entire blanket il of the paper 10.
："Pressure on 19? With the role of pushing money.

FIG. 15 is a diagram briefly explaining the configuration of a printing apparatus that combines the steps explained in FIGS. 8 to 14 into one. 1st
In Figure 5, 12Vi dampening device, 13 inking device, 14 plate 1: the same. The master 4 has a base surface on the surface of the plate cylinder 14! JIllVC is fixed. Further, the dampening water device 12 is connected to the plate 11jal 1
The non-printing hydrophilic portion of the master 4 fixed to the surface of the master 4 has the function of supplying dampening water. On the other hand, the inking device 13I''i is a oleophilic part that is applied to the print area of the master 4 and functions to supply printing ink. By the clouds, version 1
ll-! The master 4 fixed on the surface of 14 is first applied with dampening water to prevent printing ink from adhering to the non-image areas by a dampening water device 12, and then made oleophilic by an inking device 13. Printing ink is applied to each image area. Next, the printing ink 8i'' on the master 4 is transferred to the surface of the blanket 9, and then transferred to the surface of the ink 1Q.

Now, when it comes to making a double master, there are two methods: a direct plate making method that uses silver halide, and an electrofax plate making method that uses electrophotography.

The following is a simple 1'5. Explain the method. In this direct plate-making method that uses one coat of silver halide, the master is called a wide-ranging beast copy master.

FIG. 16 is a diagram showing a cross section of a diffusion transfer master using the one-sheet method before plate making. In FIG. 16, the base 3 mentioned above is made of paper treated to be waterproof. 1
5 is an anti-nolation layer, 16 is a silver emulsion layer, and 17 is a surface layer. This surface layer 17 is made of a water-developable layer consisting entirely of gelatin, and has silver and silver sulfide particles dispersed therein, which serve as nuclei during development of the inner layer 1c, and the surface layer 17 itself has no photosensitivity.

Next, a method for making a plate for a diffusion transfer master will be described with reference to FIGS. 17 to 20. FIG. 17 shows the state of exposure of the diffusion transfer master. In FIG. 17, 18 is a manuscript, 19 is a plate-making camera, 2o is a diffusion transfer master, and 21 is a lens. First, the image lines of the original 18 are exposed by the lens 21 onto the surface of an enlarged copying master 20 which is set inside a plate-making camera. 1st
FIG. 8 1ζ± shows how the exposed diffusion transfer master 20 is developed. In FIG. 18, 22 is a developer. As shown in FIG. 18, the exposed diffusion transfer master 20d is developed in a developing device 22.

At this time, silver salt is developed from the silver emulsion layer in the diffusion transfer master 20, and metallic silver is deposited on the surface and in the layer. 19th
The figure shows the diffusion transfer master 20 being fixed 7? It shows.

In FIG. 19, 23 is a fixing solution, which serves to stabilize the remaining silver salt in the diffusion transfer master 2oK8 after development. do.

FIG. 20 shows a schematic cross-sectional view of the completed diffusion transfer master 20. In FIG. 20, the diffusion transfer master 20 (7) fi is an oleophilic material covered with metallic silver deposited by physical development. It can be seen that the image is divided into an image area 1 shown in the figure and a non-image area 2 mainly composed of gelatin.

Next, the Electrofunks plate-making method using the electrophotographic method will be briefly explained. This electrofunk 7. The master used in the plate-making method is CP C (C
oated Paper Copying) is called the master.

Figure 21 shows a cross section of a CPC master made by one-step Lectroffax platemaking before platemaking. It shows.

In FIG. 21, the base 3 mentioned above is made of paper treated with water-resistant gold.
4 is an intermediate layer, and 25 is a photoconductive layer.

The photoconductive layer 25 is mainly composed of a photoconductor 1c made of oxidized lead-based material, resin-based material, or the like. Also, the intermediate layer 24 includes the base 3 and the photoconductive layer 25? It acts as an adhesive. Here, an image is formed on the surface of the CPC master using toner according to the principle of electrophotography.

The GPC master plate making method will be described below with reference to FIGS. 22 to 25.

Figure 22 shows a CPC master that has been corona discharged in advance? Shows how it is exposed. In FIG. 22, 26 is a CPC master. The surface of this CPC master 26 is negatively charged in advance by corona discharge. And manuscript 18
The image line is exposed to light on the surface of the CPC master 26 which is set inside one plate-making camera by the lens 211. At this time, the CPC master 26 receives light irradiation. The resistance of the portion of the photoconductive layer 25 decreases, discharge occurs, and the negative charge disappears.On the other hand, the portion of the photoconductive layer 26 that has not been irradiated with light is negatively charged to -i8. Figure 23 shows the CPC master 26 after exposure.
This shows how the entire image is developed. In Figure 23,
2A is a developer, in which toner 28 is dispersed. Then, the exposed CPC master 26 is developed by immersing it in a developer 27. At this time, the toner 28 in the current retaining liquid 27 selectively adheres only to the portions that are not irradiated with light from the apC master 26 and remain negatively charged.
Object formation is performed. FIG. 24 shows the state in which the CPC master 26 has been developed. In FIG. 24, toner 28 is selectively adhered to the surface of CPC master 26. In FIG. FIG. 25 shows how the toner 28 on the ape master 26 is kept constant i3. Second
In FIG. 5, 29 is a heating heater. In FIG. 25, the toner 28 formed into an image on the CPC master 26 is thermally fused by the heat of the heater 29 and then fixed. FIG. 26 shows how the entire non-printing area of the apC master 26 is made hydrophilic.

In FIG. 26, 30 is an etching solution.

Here, the main component of the photoconductive layer 25 on the surface not covered with the toner 28 of the CPC master 26, for example, zinc oxide, is exposed, and since zinc oxide itself is lipophilic,
It is necessary to make it hydrophilic by using an etching liquid 30 containing entirely phosphoric acid.

Figure 27 is a cross-sectional view 2 of the completed CPC master 26.
It shows. In Figure 27, cpc master 2
On the surface of 6, there is an image area 1 showing lipophilicity due to the toner 28.
It can be seen that a non-image area 2 made hydrophilic by the etching liquid 30 is formed, and the dampening water θ is adhered thereto.

Problems to be Solved by the Invention However, the master plate making method for light printing as described above has problems in terms of cost and ease of use.

First, in the direct plate-making method that uses silver salt, expensive silver salt is used in the diffusion transfer master itself, which increases the cost of the master itself. In order to reduce the amount of silver salt used in order to reduce this cost, metallic silver must be used in the printing ink receiving portion, and there is an inherent limit. Furthermore, when printing a large area, a master area proportional to the area and a proportional amount of silver salt are consumed.

Furthermore, the diffusion transfer master itself is not durable enough to be used many times, which is also a factor in increasing costs.

Next, in the electrofax plate making method using electrophotography, the CPC master itself is cheaper than the diffusion transfer method because no expensive silver salt is used.

However, the electrofax plate-making method requires a special device for performing corona discharge.

Furthermore, both the electrofax plate-making method and the direct plate-making method using silver salt require a highly accurate and expensive plate-making device. That is, a plate-making camera including a lens, a light source, etc., a developing tank, a fixing tank, etc. are required. Moreover, since liquid is inevitably used in the plate making process, there is a limit to the simplification of the structure. At the same time, there are consumables such as developer and master, maintenance is required, and there are limits to automation.

Also, either method requires a manuscript.

This manuscript is then photographed and printed, so the manuscript must be of extremely high quality in order to maintain the quality of the printed matter.

In view of the above-mentioned problems, the present invention provides a printing master and its manufacturing method that is inexpensive, highly productive, and can be created in an extremely short time without using a plate-making device using a lens or the like. The purpose is to provide

Means for Solving the Problems In order to solve the above-mentioned problems, the stamps and printing masters of the present invention are formed by thermally transferring a thermal transfer material directly and selectively onto a base as printing lines.

Further, in the method for manufacturing a printing master of the present invention, a thermal transfer material is selectively thermally transferred onto a base, and printing lines are directly formed on the base.

Function: According to this configuration, by directly thermally transferring the lipophilic image-forming material t onto the base without using the entire optical system, plate making can be performed without an original.

In addition, master plate making can be easily performed in a short time without using expensive raw materials such as silver salt, and without making hands dirty.

EXAMPLE Hereinafter, an example of a printing master of the present invention using a thermal head as a heating element will be described with reference to the drawings. FIG. 1 is a diagram completely explaining an example of plate making of a printing master in an embodiment of the present invention. In FIG. 1, 31 is a thermal transfer film having a lipophilic line-forming material on its surface.

32 is a winding roller, which winds up the entire thermal transfer film 31. 33 is an external signal that electrically drives the thermal head 34. 35 is the base film and corresponds to the pace of the master. While the thermal transfer film 31 is being wound around a winding roller 32, the base film 3 is passed to a thermal head 34 driven by an external signal 33.
A lipophilic streak-forming material is selectively thermally transferred onto the surface of 5.

Here, the thermal head 34 is manufactured by Japanese Patent Application Laid-open No. 61-666.
This is known from Publication No. 62, etc., and has a structure including, for example, a thick film conductor, 9 common electrodes, 9 individual electrodes, and 9 heating elements on an alumina substrate with a glass layer, and these surfaces have a high resistance to corrosion resistance. Protected by a wear layer. And thick film conductor, common electrode.

The heating element is heated by the current flowing through the individual electrodes 2, and the image forming material on the thermal transfer film 31 is transferred to the base film 35.
selectively thermally transferred onto the surface.

2, 3, 4, and 5 below regarding the plate making of the printing master configured as described above.

The details and operation will be fully explained using FIG.

FIG. 2 is an enlarged sectional view of the tip of the thermal head 34. FIG. In FIG. 2, numeral 36 is a transfer base, the surface of which is coated with a lipophilic line-forming material. This transfer paste 3e and the image forming material 37 form the thermal transfer film 31. and - the image forming material 37 applied on the transfer paste 36 is selectively thermally transferred onto the base film 35 by a thermal plate 34 driven by an external signal 33; The image forming material 37 remains on the transfer base 36 and is wound up by the winding roller 32.

FIGS. 3 to 6 are diagrams showing the master processing steps in the present invention. In FIG. 3, the base film 35
The image forming material 37 is shown selectively thermally transferred by the thermal head 34 at the top. FIG. 4 shows the etching process. In FIG. 4, reference numeral 38 denotes an etching liquid, which serves to make the surface of the portion of the base film 35 not covered with the image forming material 37 hydrophilic. At this time, the image forming material 37 is mixed with the etching liquid 3.
The influence of 8 is bad for the entire party. This etching step may be omitted when the image forming material 37 is thermally transferred to a base film whose surface has been made hydrophilic in advance. Figure 5 shows the completed master 2. In FIG. 5, the surface of the line forming material 37 maintains oil-based properties, and the line forming material 37
The portion of the surface of the base film 350 that is not covered by the surface 2 is kept hydrophilic, and dampening water 39 is attached thereto.

FIG. 6 is an oblique view of a printing master completed according to the present invention. In FIG. 6, the drawing line forming material 37
This figure shows the formation of a lipophilic printed area and a hydrophilic non-printed area.

In the present invention, master plate making can be performed directly by applying a signal for driving the thermal head from outside, for example by directly connecting the output of a computer, or by transmitting the signal via various communication circuits. This enables direct plate-making of masters for newspaper printing, etc. by trenching and transmission, and direct plate-making of masters by facsimile.

By taking advantage of these features of the present invention, you can
Masters can be created extremely easily and in a short time, and can be applied not only to the field of light printing but also to other printing fields.

In addition, as streak-forming materials, for example, pigments, Carnauhawasox, ester waxes, and oils.

A mixture of 2Q, 20, 40, 10, and 10% by weight of each other has excellent lipophilicity, exhibits stable acid resistance and alkali resistance, and is stable against various etching solutions. ing. However, it goes without saying that many other line-forming materials can be used in the present invention.

The present inventors conducted an experiment on master plate making using an 8 mm end face type thermal head all around the circumference. In this case, the driving voltage of the thermal head was 10 volts, and a PET (polyethylene terephthalate) film was used as the heat transfer film, and 6 volts was used as the image forming material on top of this.
Wax ink for thermal transfer printers with a melting point of 8°C approx.
A coating of gram/m2 was used. Also,
A commercially available CPC master was used as the base film of the master, and the image forming material was selectively thermally transferred onto the surface of the CPC master using a thermal head, and all plate making was performed. Next, after being treated with a commercially available etching solution, it was set in an offset printing machine that normally performs offset printing H:Ik using an electrofax method using a commercially available offset printing ink. The offset printed products according to the present invention were clean and did not smudge in any way compared to the conventional ones.

As another method of utilizing the invention, an ordinary thermal transfer printer can also be used as a master plate-making device in the invention. 1, not only in the light printing field - ovicidal
It is also possible to apply this method to offset lithographic printing, etc.

In addition to the thermal head, we also have an infrared laser in the pond.
Needless to say, methods that can obtain local heating such as electron beams, electromagnetic waves, and lines of magnetic force can also be used.

Effects of the Invention As described above, the present invention is characterized in that the image is formed by selectively thermally transferring the image forming material, and it is possible to easily and cheaply produce a complete master of one piece without a manuscript. can.

The master in the present invention is printed on a printing machine without any distinction from conventional masters. In addition, the master of the present invention does not require photographing the entire original, does not require a special optical system, and directly makes the entire master.
It becomes possible to make plates in an extremely short time and without getting your hands dirty.

Furthermore, by taking advantage of the fact that it is driven by an external signal, master plate making may be performed directly from a signal from a facsimile or a word processor.

Further, by using a storage medium such as a floppy disk as an external signal, a master can be easily made. Moreover, the advantage of being able to do this at low cost and with high speed i is great. Therefore, the industrial value of the present invention is extremely large in the future information society.

[Brief explanation of drawings]

FIG. 1 is a diagram illustrating an example of plate making of a printing master in an embodiment of the present invention, FIG. 2 is an enlarged sectional view of the tip of a thermal head for making a master of the present invention, and FIG.
FIGS. 4 and 5 are diagrams showing the processing steps of the master according to the present invention, FIG. 6 is an oblique view of the master completed according to the present invention, and FIG. 7 is an oblique view of the conventional master 2. , Fig. 8, Fig. 9, Fig. 10, Fig. 11, Fig. 1
Figures 2, 13, and 14 show all conventional masters (・+,
A diagram for explaining the printing process used in Figure 15, 11i, and the purchase of a printing device that combines the processes in Figures 8 to 14 into one.
``y,'' (r) Figure 16 is a diagram showing a cross section of a conventional diffusion transfer master using one-sheet-one-printing method before plate making, Figures 17, 18, and 19 ← Figure 20 is a schematic cross-sectional view of the completed conventional diffusion transfer master, and Figure 21 is the conventional electrofax plate making method. Figures 22 and 23 are cross-sectional views of the CPC master before plate making.
FIG. 7 is a schematic cross-sectional view of the completed conventional CPC Manukoo. 31... Thermal transfer film, 32... Winding roller, 33... External signal, 34...
... Thermal head, 35 ... Base film, 36 ... Transfer base, 37 ... Image forming material. Name of agent: Patent attorney Toshio Nakao and 1 other person31
- Ichijuku Somimi Furumu 32 --- A steep V ---My ear\-su,, 37---Picture form, collar No. 2 Figure 3 Figure 4 Figure 33 Figure 5 3Z Figure 6 Figure 7 Figure 8 Figure 12 Figure 13 Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 Figure 21 Figure 25 Figure 26 Figure 27 6

Claims (2)

[Claims] (1) A printing master in which a thermal transfer material is directly and selectively thermally transferred as printing lines onto a base. (2) A method for producing a printing master, in which a thermal transfer material is selectively thermally transferred onto a base to form printing lines directly on the base.