JPH05281748A - Method and apparatus for producing printing plate - Google Patents

Abstract

(57) [Summary] [Structure] Printing plate 50 using the photosensitive plate 1 from the original drawing 8
Which is a device for producing the image data, a scanner 13 for converting the original image 8 into image data, a layout scanner 15 for converting the image data into a required image pattern 20 suitable for a printing plate to be produced, and an exposure light source 11 for shielding light. An ink jet device 17 for forming an image 20 on the photosensitive plate 1 by depositing the ink 9, an exposure device 19 for exposing the photosensitive plate 1 with an exposure light source 11, and a developing device for developing the photosensitive plate 1. 21 are provided. [Effect] The original drawing 8 is converted into image data, and the light-shielding substance 9 is directly attached to the image portion of the photosensitive plate 1 by this image data. Therefore, the printing plate 50 is not used.
Can be produced. Further, instead of the plate-making film 5, the light-shielding substance 9 is attached to the image area 20 of the photosensitive plate 1 and exposed, so that the conventional printing plate can be used as it is.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is a printing plate used for printing such as offset printing and screen printing, which is for producing a photosensitive printing plate for forming an image pattern by photosensitization without using a plate-making film. The present invention relates to a method and an apparatus for producing a printing plate suitable for.

[0002]

2. Description of the Related Art In the preparation of a photosensitive printing plate for forming an image pattern by photosensitization, generally, as shown in FIG. 8 and FIG. The plate-making film 5 is produced from the image pattern arranged in the layout, and the pre-sensitized plate (hereinafter referred to as P
The plate making film 5 is placed on an S plate) 1 or a waterless plate (not shown), exposed by ultraviolet rays, exposed to light, and developed to develop the image area 20a and the non-image area 20.
A printing plate on which an image pattern 20 composed of b is formed is produced.

FIG. 7 shows the PS plate 1 which is now generally used as a photosensitive plate member. A hydrophilic layer 3 is formed on the surface of an aluminum support 2, and a photosensitive layer 4 is further provided on the hydrophilic layer 3. It is a thing. As shown in FIG. 8, a plate-making film 5 prepared from an original drawing is placed on the PS plate 1 at a predetermined position, and then the photosensitive layer 4 is exposed to ultraviolet rays from an exposure light source 11 as shown in FIG. Then, as shown in FIG. 11, the PS plate 1 is developed to form an image pattern 20 composed of an image area 20a and a non-image area 20b, thereby producing a printing plate 30.

Offset printing is performed as shown in FIG. 12 using the printing plate 30 thus produced. The printing ink 24 is applied to the lipophilic image area 20a, the dampening water 25 is filled in the hydrophilic layer of the non-image area 20b, and printing is performed by utilizing the repulsion of oil and water.

In recent years, image processing devices have been used to
In many cases, the original drawing is read, converted into image data consisting of binary values of X and Y, and characters, figures, photographs, etc. are treated as digital data of a computer.

Furthermore, using this image data, without making the plate-making film 5, as shown in FIG. 10, the laser irradiation device 23 is used and the photosensitive layer 7 of the image area 20a of the photosensitive plate 6 is used. A direct plate-making method in which a laser beam 23a is directly irradiated onto the surface of the substrate to expose it and then developed as shown in FIG. 11 to form an image pattern 20 composed of an image area 20a and a non-image area 20b is there.

[0007]

However, each of the conventional printing plate manufacturing methods described above has the following problems. First, in the method shown in FIGS. 8 and 9, since the plate-making film 5 is produced as described above, an intermediate material is required and the cost becomes high. Furthermore, since the steps of producing the plate-making film 5, exposing the photosensitive plate 1 and developing the photosensitive plate 1 are separated, a waiting time is lost between the steps, which leads to a longer delivery time. There is.

Further, in the method shown in FIG. 10, since the plate making film 5 is not used, the cost can be reduced, and further,
By providing the image processing device and the laser irradiation device online, there are advantages that the loss between steps can be reduced and the plate making precision can be improved. However, in order to perform exposure by irradiation with a laser beam, it is necessary to use, for example, an OPC sensitive material or a highly sensitive sensitive material such as a silver salt emulsion as the photosensitive layer of the photosensitive plate. However, since printing plates using these sensitive materials cannot use conventional PS plates and the like, printing durability is inferior to that of conventional printing plates.
It is necessary to newly set up a storage area for printing plates.
Since various conditions at the time of exposure, development, etc. are different, there is a problem that dedicated equipment is required.

The present invention has been made in consideration of the above points, and a conventional PS plate or the like can be used, and a printing plate can be produced without using an intermediate material such as a plate-making film. An object of the present invention is to provide a method and an apparatus for producing a printing plate that can be used.

[0010]

The invention according to claim 1 is
A method of producing a printing plate from a master image using a photosensitive plate, comprising an image conversion step of converting the master image into image data, and converting the image data into a required image pattern suitable for the printing plate to be prepared. Data conversion step, a light-shielding substance attaching step of forming a light-shielding substance that shields an exposure light source to form the image pattern on the photosensitive plate body, and the photosensitive plate after the light-shielding substance attaching step. It is characterized by comprising an exposing step of exposing the body with the exposing light source, and a developing step of developing the photosensitive plate body after the exposing step.

The invention according to claim 2 is characterized in that, in the light-shielding substance attaching step, the light-shielding substance is attached to the photosensitive plate body by an ink jet device.

According to a third aspect of the present invention, there is provided an apparatus for producing a printing plate from an original drawing by using a photosensitive plate, and an image converting means for converting the original drawing into image data and the image data should be prepared. Data conversion means for converting into a required image pattern suitable for a printing plate; light-shielding substance attaching means for attaching the light-shielding substance that shields the exposure light source to form the image pattern on the photosensitive plate; It is characterized by comprising an exposing means for exposing the lithographic plate and a developing means for developing the photosensitive plate.

The invention according to claim 4 is characterized in that the light-shielding substance attaching means is an ink jet device.

[0014]

According to the first aspect of the present invention, the original drawing is converted into image data, and the light-shielding substance is directly attached to the image pattern of the photosensitive plate according to the image data. Therefore, an intermediate material such as a plate-making film is not used. A printing plate can be prepared. Further, instead of a plate-making film or the like, a light-shielding substance is attached to the image pattern of the photosensitive plate to expose it.
The conventional PS plate or the like can be used as it is.

According to the second aspect of the invention, since the ink jet device is used in the light-shielding substance attaching step,
An image pattern can be formed by attaching a light-shielding substance onto the photosensitive plate according to the image data, and the image conversion process and the data conversion process can be performed online with the image processing apparatus.
Further, it is possible to use the existing ink jet device as it is.

According to the invention described in claim 3, a printing plate can be produced without using a plate-making film. In addition, since the conventional PS plate can be used as it is, high printing durability can be maintained, and since it is not necessary to change the conditions such as exposure and development from the conventional one, the existing equipment such as a developing machine can be used. Can be used.

According to the fourth aspect of the present invention, since the light-shielding substance attaching means is an ink jet device and the image conversion means and the data conversion means can be brought online, a highly accurate printing plate can be produced. And there is no loss between the steps from reading the original drawing to developing the photosensitive plate,
It is possible to shorten the delivery time of printing plate production. Also, existing ink jet devices can be used.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments shown in the drawings. Here, for example, description will be given using an example in the case of producing a positive type printing plate by offset printing. FIG. 1 shows an apparatus for producing a printing plate according to the present invention, for example, an offset printing apparatus for producing a printing plate 50 using a positive type PS plate (photosensitive plate) 1. It is a thing. In FIG. 1, parts common to those of FIGS. 8 to 10 shown as a conventional example are designated by the same reference numerals. In this embodiment, an apparatus 26 for producing the printing plate 50 from the original drawing 8, which is a scanner (image converting means) 13 for converting the original drawing 8 into image data,
A layout scanner (data conversion means) 15 for converting the image data obtained from this image into a required image pattern 20 suitable for the printing plate to be prepared, and a light-shielding ink (light-shielding substance) 9 for shielding the exposure light source 11 from light. Attach P
An ink jet device (light-shielding substance adhering means) 17 for forming an image pattern 20 on the S plate 1, an exposure device (exposure device) 19 for exposing the PS plate 1 with an exposure light source 11, and a PS
A developing device (developing means) 21 for developing the plate 1 is provided.

The scanner 13 reads an original drawing of characters, drawings, photographs, etc., and converts it into numerical data consisting of binary values of X and Y, and an original drawing color of Y: yellow, C: cyan, M. : Magenta, BL: Black, 4
It has a color separation device that separates it into colors.

The layout scanner 15 is equipped with a halftone dot separation device 16 for separating color shades into halftone dots.

The ink jet device 17 has the same ink (light-shielding substance) 9 as the ordinary ink jet device.
Is a device for ejecting as a droplet particle from the nozzle 17a and electrically controlling the ejection direction of the particle to draw a pattern.

The PS plate 1 according to the present invention has a hydrophilic layer 3 formed on the surface of an aluminum support 2 and a photosensitive layer 4 provided on the upper surface thereof, as in the case shown in FIG. In this case, as the aluminum support 2, a high-purity and high-strength aluminum plate having a purity of 99% or more is used. The surface 2a of the aluminum support 2 is grained in order to enhance the adhesion of the photosensitive layer 4, the reproducibility of halftone dots, the water retention during printing, and the like. As the photosensitive layer 4, for example, a substance obtained by mixing a compound such as o naphthoquinonediazide compound and a resin is used, and it is sensitive to blue to ultraviolet rays.

The exposure device 19 has an exposure light source 11 such as ultra-high pressure mercury.

The developing device 21 is provided with a developer tank 28 filled with a developer 22 for developing the PS plate 1. Although not shown, a cleaning device for cleaning and drying the PS plate 1 after development and a drying device are provided on the rear side of the developer tank 28.

The stocker 29 for receiving the PS plate 1 after development from the developing device 21 and temporarily stocking it,
It is provided after the developing device 21.

Further, here, after the PS plate 1 is developed, a burning processing device for further improving printing durability and a gum coating processing device for protecting the non-image area of the PS plate 1 and enhancing hydrophilicity may be provided. Good.

The printing plate producing apparatus 26 according to the present embodiment is
Although configured as described above, each of the scanner 13, the layout scanner 15, the ink jet device 17, the exposure device 19, and the developing device 21 may have an integrated structure due to the structure of the equipment. The structure may be divided.

With the operation of the printing plate producing apparatus 26,
One embodiment of the method for producing a printing plate according to the present invention will be described with reference to FIGS.

First, the original drawing 8 such as characters, figures, and photographs is read by the image processing device of the scanner 13 and X,
The image data is converted into binary image data of Y. Further, here, when the original drawing is in color, it is separated into four colors of Y: yellow, C: cyan, M: magenta, and BL: black.
Converted to image data of one image pattern (SP
1).

Next, the layout scanner 15 uses the image data to specify the layout position of the image pattern 20 in the PS plate 1. Also, here, so-called "imposition" can be performed in which a large number of image patterns 20 are arranged in the PS plate 1. In addition, the halftone decomposing device 16 is used to separate the shade of color into halftone dots. Further, here, the positive printing or the negative printing is designated, and the image pattern 20 is converted into a desired form of the positive image or the negative image. The image data of the required image pattern 20 which is converted by the layout scanner 15 and is suitable for the printing plate 50 to be produced is the ink jet device 17
Is transmitted online or by using a medium such as a magnetic tape (SP2).

Next, in the ink jet device 17, as shown in FIG. 3, a substance that shields ultraviolet rays, for example, ink 9, is ejected from the nozzle 17a at the tip of the ink jet device 17 to eject the PS plate 1. Surface 4 of photosensitive layer 4
The image pattern 18 with the ink 9 is applied to the image area 20a of a.
Are formed (SP3).

Next, in the exposure device 19, as shown in FIG. 4, the PS plate 1 on which the image pattern 18 is formed is irradiated with ultraviolet rays by the ink 9 to form an image on the photosensitive layer 4 of the PS plate 1. The image pattern 20 including the portion 20a and the non-image area 20b is formed (SP4).

When the PS plate 1 on which the image pattern 18 is formed by the ink 9 is irradiated with ultraviolet rays from the exposure light source 11, the photosensitive layer 4c below the non-image area 20b on which the ink 9 is not adhered is exposed to ultraviolet rays. Photosensitizes and photo-decomposes or photo-isomerizes to generate a hydrophilic group, which becomes soluble in an alkaline aqueous solution or the like. On the other hand, the photosensitive layer 4b below the image area 20a to which the ink 9 adheres is shielded by the ink 9 and is not exposed.

Further, as shown in FIG. 5, the exposed PS plate 1 is developed with the alkaline developer 22 by the developing device 21 (SP5).

During exposure, the photosensitive layer 4c in the non-image area exposed to light is dissolved and the hydrophilic layer 3 is exposed on the surface. Also,
The portion of the photosensitive layer 4b that was not irradiated with light during exposure remains, and an oleophilic image area 20a is formed. Here, since the ink 9 elutes in the developing solution 22, it is possible to wash the ink 9 in advance by providing a cleaning means in front of the developing device 21 in order to prevent this.

After the PS plate 1 is developed, it may be subjected to a burning process for further improving printing durability or a gum coating process for protecting the non-image area of the PS plate 1 and enhancing hydrophilicity.

A predetermined printing plate 50 is manufactured by the above steps. Then, in this printing plate 50, as shown in FIG. 6, the printing ink 24 is applied to the lipophilic image area 20a, and the dampening water 25 is filled in the hydrophilic layer of the non-image area 20b. Printing is performed by using the repulsion of water.

In the present invention, the original drawing 8 is thus converted into image data, and the ink 9 is directly applied to the image pattern 20 of the PS plate 1 by using the image data to expose the image. , The plate-making film 5
The printing plate 50 can be produced without using an intermediate material such as, and the material cost can be reduced. Further, it is possible to manufacture the printing plate 50 with high accuracy. Further, since the process from the reading of the original drawing to the development of the PS plate 1 can be performed without any loss between steps, it is possible to shorten the delivery time of the printing plate 50.

Further, since the light-shielding ink 9 is attached to the image pattern portion of the PS plate 1 instead of the plate-making film 5, the conventional PS plate 1 can be used as it is. For this reason,
Since high printing durability can be maintained, there is no need to newly provide a storage place for the PS plate 1, and there is no need to change the conditions of exposure, development, etc., from those of the conventional exposure apparatus. The existing equipment can be used as is for the developing machine and the like.

Furthermore, since the ink 9 is used as the light-shielding substance, no post-treatment is required after the ink is attached to the PS plate 1, and removal after exposure is easy. Not limited to the above examples, for example, a printing method using a photosensitive printing plate such as a waterless plate for offset printing, a plate for screen printing, or the like as long as it is a printing method according to the present invention. Needless to say, the manufacturing apparatus may be applied to a printing plate used in another printing method.

[0041]

As described above, according to the method of claim 1, a method for producing a printing plate from a master image using a photosensitive plate, which is an image conversion step of converting the master image into image data And an image conversion step of converting image data into a desired image pattern suitable for the printing plate to be produced, and a light-shielding substance for forming an image pattern on the photosensitive plate by attaching a light-shielding substance that shields the exposure light source. Since it comprises an attaching step, an exposing step of exposing the photosensitive plate body with an exposure light source after the light shielding substance attaching step, and a developing step of developing the photosensitive plate body after the exposing step. A printing plate can be produced without using an intermediate material such as a plate-making film. Further, instead of a plate-making film or the like, since a light-shielding substance is attached to the image area of the photosensitive plate member and exposed, a conventional PS plate or the like can be used as it is.

Further, according to the method of claim 2, in the light-shielding substance attaching step, the light-shielding substance is attached to the photosensitive plate body by the ink jet device. An image pattern can be formed by adhering a volatile substance, and it becomes possible to put the image conversion device and the data conversion process on-line with the image processing apparatus. Further, the existing ink jet device can be used as it is, and the production can be performed at low cost.

According to a third aspect of the present invention, there is provided an apparatus for producing a printing plate from an original drawing, which is suitable for the image converting means for converting the original drawing into image data and the printing plate for producing the image data. Image conversion means for converting into a desired image pattern, light-shielding substance adhering means for adhering a light-shielding substance for shielding the exposure light source to form an image pattern on the photosensitive plate, and exposing means for exposing the photosensitive plate And a developing means for developing the photosensitive plate member, so that a printing plate can be prepared without using an intermediate material such as a plate-making film,
Material costs can be reduced. Further, since the conventional PS plate or the like can be used as it is, high printing durability can be maintained, and it is not necessary to newly provide a storage place for the printing plate. Further, since it is not necessary to change the conditions of exposure, development and the like from the conventional one, the existing equipment such as a developing machine can be used.

Further, according to the apparatus of the fourth aspect, since the light-shielding substance attaching means is an ink jet device, and the image conversion means and the data conversion means can be connected to the image processing apparatus online, so that It is possible to produce a printing plate with high accuracy, and there is no loss in the steps from the reading of the original drawing to the development of the photosensitive plate, and the delivery time of the printing plate can be shortened.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a printing plate producing apparatus according to the present invention.

FIG. 2 is a flowchart showing steps according to the method for producing a printing plate according to the present invention.

FIG. 3 is a cross-sectional view showing a step of attaching a light-shielding substance by the method for producing a printing plate according to the present invention.

FIG. 4 is a cross-sectional view showing an exposure step in the method for producing a printing plate according to the present invention.

FIG. 5 is a cross-sectional view showing a developing process of the photosensitive plate according to the invention.

FIG. 6 is a cross-sectional view showing a printing plate according to the present invention together with printing ink and the like attached to it.

FIG. 7 is a cross-sectional view of a photosensitive plate body according to the present invention.

FIG. 8 is a cross-sectional view showing an example of a conventional printing plate manufacturing method.

FIG. 9 is a cross-sectional view showing an example of a conventional printing plate manufacturing method.

FIG. 10 is a cross-sectional view showing another conventional example.

FIG. 11 is a cross-sectional view showing an example of a conventional printing plate manufacturing method.

FIG. 12 is a cross-sectional view showing a printing plate produced by a conventional method together with printing ink and the like attached to it.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 PS plate (photosensitive plate) 8 Original image 9 Ink (light-shielding substance) 11 Exposure light source 13 Scanner (image conversion means) 15 Layout scanner (data conversion means) 17 Ink jet device (light-shielding substance adhering means) 19 Exposure device (Exposure means) 20 Image pattern 21 Developing device (Developing means) 26 Printing plate making device 50 Printing plate

Claims (4)

[Claims] 1. A method for producing a printing plate from a master image by using a photosensitive plate, which comprises an image conversion step of converting the master image into image data, and a step required for the printing plate on which the image data is to be prepared. After the data conversion step of converting into an image pattern, a light-shielding substance attaching step of forming a light-shielding substance that shields the exposure light source to form the image pattern on the photosensitive plate body, and the light-shielding substance attaching step. A method for producing a printing plate, comprising: an exposure step of exposing the photosensitive plate member with the exposure light source; and a developing step of developing the photosensitive plate member after the exposure step. .. 2. The method for producing a printing plate according to claim 1, wherein, in the light-shielding substance attaching step, the light-shielding substance is attached to the photosensitive plate member by an ink jet device. 3. An apparatus for producing a printing plate from an original drawing by using a photosensitive plate, and an image conversion means for converting the original drawing into image data, and a required device suitable for the printing plate for producing the image data. Data conversion means for converting into an image pattern, a light-shielding substance adhering means for adhering a light-shielding substance that shields the exposure light source to form the image pattern on the photosensitive plate, and exposing the photosensitive plate An apparatus for producing a printing plate, comprising: an exposing unit; and a developing unit for developing the photosensitive plate member. 4. The printing plate producing apparatus according to claim 3, wherein the light-shielding substance attaching means is an ink jet device.