JP2007279325A - Device and method for manufacturing photosensitive resin plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and a device capable of manufacturing a liquid photosensitive resin relief printing plate excellent in plate thickness precision. <P>SOLUTION: In the method for manufacturing the photosensitive resin plate for relief printing, a transparent film capable of transmitting active light is placed over at least one surface of a liquid photosensitive resin layer disposed between two base substrates at least one of which is a transparent substrate, and after image forming exposure to the active light is carried out from one surface or both the surfaces, development processing is performed. The manufacturing method for the photosensitive resin plate for relief printing is characterized in that the gap between the two base substrates is increased within a range wherein the upper base substrate is contacted after the formation of the liquid photosensitive resin layer and before or during the image forming exposure. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a method for producing a photosensitive resin plate for letterpress printing such as cardboard printing, film printing, preprint printing, and label printing.

  In general, in order to produce a printing plate using a liquid photosensitive resin, first, as shown in FIGS. 1, 2, and 4, the negative film 3 and the cover film 4 are placed on the lower transparent base plate 1 by means such as vacuum. The photosensitive resin layer 5 is laminated thereon, and the base film 6 and the masking film 7 are overlaid thereon. After that, as shown in FIG. 5, the base portion of the relief portion is formed by irradiating the active light from the upper lamp 9 through the upper transparent substrate 2 placed on the spacer 8 set to determine the thickness of the photosensitive resin plate. Masking exposure is performed, and then a relief exposure is performed by irradiating active light from the lower lamp 10 through the negative film 3 from the lower transparent substrate 1 side to form an image of the relief portion, and then the development process is performed. Do. Alternatively, after performing the relief exposure, the masking film 7 may be removed, and back exposure for stably fixing the formed relief portions A and B to the base film 6 may be performed from the upper transparent substrate 2 side.

  Next, an uncured portion is washed out with a suitable detergent and developed, and post-exposure and drying are performed to obtain a printing plate. Alternatively, without using a masking film, the negative film 3 and the cover film 4 are placed in close contact on the lower transparent base plate 1, the photosensitive resin layer 5 is laminated thereon, and the base film 6 is overlaid thereon. Thereafter, back exposure is performed to form the base of the plate by irradiating active light from the upper lamp 9 through the upper transparent substrate 2 placed on the spacer 8 set to determine the thickness of the photosensitive resin plate. Next, a method of obtaining a plate by performing relief exposure by irradiating active light from the lower lamp 10 through the negative film 3 from the lower transparent substrate 1 side, and developing, post-exposure and drying is widely used.

By the way, in such a manufacturing method, the bucket 11 containing the liquid photosensitive resin is run on the spacer 8 having a height set to a predetermined plate thickness, and the liquid photosensitive resin is placed on the lower transparent substrate 1. Lamination. Immediately after the lamination, due to the surface tension of the liquid resin and the resin flow at the outer peripheral portion, the plate thickness at the central portion of the plate tends to be thick and the plate thickness at the outer peripheral portion of the plate tends to be low. A printing relief plate having a predetermined plate thickness is manufactured by sandwiching the same between two transparent substrates having a space limited by a predetermined spacer height. However, sufficient time for the liquid photosensitive resin to flow is sufficient to achieve sufficiently small plate thickness accuracy by sandwiching between two transparent support substrates, that is, the difference between the highest plate thickness and the lowest plate thickness. I need to wait. Doing so will increase manufacturing time and reduce productivity. A conventional example of a method of waiting for such a sufficient time is described in Patent Document 1. Further, if the waiting time is shortened in order not to reduce the productivity, a printing relief plate having a large plate thickness accuracy may be produced. When printing is performed using such a printing plate, ink blurring occurs, making it difficult to obtain a clear printed image, and unfavorable situations such as obtaining a printed image with a large dot gain occur.
JP-A-8-305006

  The present invention overcomes the disadvantages of the conventional method described above, and forms a plate surface with a small difference in height between the plate center and the plate outer periphery in a short production time, and is clear and free of ink blurring and having a dot gain. It is an object of the present invention to provide a method for producing a relief printing plate that gives a small printed image, and a plate making apparatus used therefor.

  In the prior art, as shown in FIGS. 1 and 2, the negative film 3 and the cover film 4 are placed in close contact with each other on the lower transparent base plate 1 by means of vacuum or the like, and the spacer 8 is placed on the bucket 11. When the photosensitive resin layer 5 is laminated while opening the bottom of the bucket while running, the central portion of the plate which hits the central portion of the bucket 11 immediately after the lamination of the liquid photosensitive resin is laminated as compared with the outer peripheral portion of the plate as shown in FIG. The amount of the laminate increased due to the influence of the surface tension, and on the other hand, the thickness of the outer periphery of the plate decreased due to the fluidity of the liquid due to the fluidity of the liquid. In this state, a plate surface having a large height difference between the plate central portion and the plate outer peripheral portion is formed. Therefore, the upper transparent substrate is placed on the spacer 8 set to determine the thickness of the photosensitive resin plate as shown in FIG. 2 and the liquid photosensitive resin layer 12 laminated higher than the height of the spacer 8 was forcibly spread by the upper transparent substrate 2. In other words, using the fluidity of the liquid resin, a standing time is provided before masking exposure, and the liquid resin at the center of the highly laminated plate is caused to flow into the liquid resin region at the outer periphery of the plate that is laminated low, The height difference between the center of the plate and the outer periphery of the plate was small.

  As a result of intensive studies to solve the above problems, the present inventor has taken a long time until the liquid resin reaches a steady state because the amount of the liquid resin forced to flow is large in the conventional method. For example, as shown in FIG. 3, the height of the spacer 8 is increased immediately after laminating the liquid photosensitive resin 5 as shown in FIG. By reducing the number, the present invention has been completed which can achieve both surprisingly high productivity and plate thickness accuracy.

That is, the present invention is as follows.
1. At least one of them is a transparent substrate, and a transparent film capable of transmitting active light is superimposed on at least one surface of a liquid photosensitive resin layer disposed between two supporting substrates, and image formation is performed by active light from one side or both sides. A method for producing a photosensitive resin plate for letterpress printing, which is subjected to development after exposure, wherein the two support substrates are formed after forming the liquid photosensitive resin layer, before image forming exposure, or during image forming exposure. A method for producing a photosensitive resin plate for letterpress printing, wherein the interval is increased within a range in contact with the upper support substrate.
2. 1. Increase the distance between support substrates by 0.05 mm or more and 0.5 mm or less. A method for producing a photosensitive resin plate for letterpress printing according to 1.
3. 1. Increase the distance between support substrates by 0.1 mm or more and 0.3 mm or less. A method for producing a photosensitive resin plate for letterpress printing according to 1.
4.1. To 3. The manufacturing apparatus used for the manufacturing method of the photosensitive resin plate for letterpress printing in any one of.

  According to the present invention, the difference in height between the central portion of the plate and the outer peripheral portion of the plate is reduced, and a plate with high plate thickness accuracy can be obtained quickly. As a result, there is no ink blur and a high quality printed matter with small dot gain. Productivity is greatly improved. In addition, since the printing plate obtained by the method of the present invention can be printed with a uniform printing pressure, the printing durability is deteriorated due to excessive local printing pressure, and the paper powder entering the printing plate during printing is reduced. Can be prevented.

  In the present invention, a negative film 3, a cover film 4, a liquid photosensitive resin 5, a base film 6, a masking film 7, and an upper transparent substrate 2 are laminated in this order on the lower transparent substrate 1 as shown in FIG. Masking exposure is performed by irradiating active light from the upper lamp 9 through the upper transparent substrate 2, then performing relief exposure by irradiating active light from the lower lamp 10 through the lower transparent substrate 1, and further removing the masking film 7. In this method, back exposure is performed by irradiating active light from the upper lamp 9 through the upper transparent substrate 2, and then the uncured liquid photosensitive resin is removed to form a photosensitive resin plate, and masking exposure is performed. Before or during exposure, the spacer height is increased so that the distance between the upper and lower transparent support substrates is increased within the range in contact with the upper support substrate. It is a method.

In the present invention, a negative film 3, a cover film 4, a liquid photosensitive resin 5, a base film 6 and an upper transparent substrate 2 are laminated in this order on the lower transparent substrate 1. A back exposure is performed by irradiating actinic light from the substrate, and then a relief exposure is performed by irradiating actinic light from the lower lamp 10 through the lower transparent substrate 1, and then the uncured liquid photosensitive resin is removed to remove the photosensitive resin plate. This is a method for producing a photosensitive resin plate in which the spacer height is slightly increased before performing back exposure or during exposure to increase the distance between the upper and lower transparent support substrates.
That is, according to the manufacturing method of the present invention, when molding and exposing the photosensitive resin, the spacer height is increased by a predetermined amount before or during the image forming exposure (masking exposure or back exposure) as the primary exposure. The distance between the upper and lower transparent support substrates is increased.

Hereinafter, the present invention will be described in more detail.
The transparent film capable of transmitting active light used in the present invention is a negative film imaged by a film production system such as an image setter, a transparent cover film, an image drawn directly on the surface by an inkjet or the like. This refers to a cover film with a negative design, a masking film imaged by a film production system such as an image setter, a transparent base film, and the like.

  In the production method of the present invention, a photosensitive resin, for example, a liquid photosensitive resin described in JP-A-1-245245, JP-A-3-226757 and the like can be used. When producing a printing plate with a normal liquid photosensitive resin, first, as shown in FIGS. 1, 2, and 3, the negative film 3 and the cover film 4 are placed on the transparent substrate 1 and processed into the transparent substrate 1. The negative film 4 is brought into vacuum contact with the transparent substrate 1 by the formed holes / grooves and vacuum piping. Further, the base film 6 is further placed on the resin layer 5 while running the bucket 11 containing the liquid photosensitive resin on the spacer set to a predetermined plate thickness and laminating the photosensitive resin layer 5. Laminate to. Thereafter, the thickness is preferably 0.05 mm or more and 0.5 mm or less, more preferably, the spacer height is increased by 0.1 mm or more and 0.3 mm or less, which is about the same as the masking film, and then the masking film 7 is stacked as shown in FIG. . Thereafter, as shown in FIG. 5, the transparent support substrate 2 is placed on the spacer set to determine the thickness of the photosensitive resin, and the base of the relief portion is formed by irradiating active light through the transparent substrate 2. Back exposure (masking exposure) is performed, and then relief exposure is performed by irradiating active light through the negative film 3 from the transparent substrate 1 side in order to form a relief portion of the image. Then, if necessary, the masking film 7 is removed, and back exposure for fixing the formed relief portions A and B and the base film 6 is performed from the transparent substrate 2 side.

  Next, the uncured photosensitive resin is washed and removed with a suitable detergent, and post-exposure and drying are performed to obtain a printing plate. Further, when a plate having a relatively small plate thickness is manufactured, the above-described masking film 7 is not used, and first, back exposure (back exposure) for forming the base of the relief portion on the entire plate surface through the transparent substrate 2 is performed. Then, in order to form a relief portion of the image, a method of performing relief exposure from the transparent substrate 1 side is performed. Also in this case, after the bucket 11 is run on the spacer set to a predetermined plate thickness and the photosensitive resin layer and the base film are laminated, 0.05 mm or more and 0.5 mm or less are preferable, preferably Increase the spacer height by 0.1 mm or more and 0.3 mm or less.

  The printing plate thus obtained has a smaller thickness difference between the plate center and the plate outer periphery than a plate produced by a conventional method. As a result, it is possible to provide a printed image having a high degree of reproducibility with respect to a document that is clear and has a small gain. The increase in the spacer height after laminating the liquid photosensitive resin is preferably 0.05 mm or more and 0.5 mm or less, more preferably 0.1 mm or more and 0.3 mm or less, and the difference in thickness between the images can be minimized. Compared to the conventional method, the plate-making time is shortened, the productivity can be improved, and the conditions are highly effective and practical. Furthermore, a plate with improved thickness accuracy can be produced by increasing the spacer height by an appropriate amount even at the initial time of back exposure.

  As the transparent substrates 1 and 2 used for the plate making, plastics such as glass, acrylic resin, polycarbonate resin, and polyvinyl chloride resin, and transparent ceramic are used.

The present invention will be described based on examples.
The plate thickness accuracy ΔT in each example and comparative example is determined as follows.
(1) Plate thickness accuracy ΔT: The difference between the minimum value and the maximum value when the plate thickness of the entire relief portion is measured at locations arranged in a lattice pattern with an interval of 50 mm or more and 150 mm or less.
(2) The allowable range of the plate thickness accuracy ΔT is determined as follows from the viewpoint of obtaining a high-quality printed matter having no ink blur and small dot gain.
：: 8/100 mm or less ○: greater than 8/100 mm and less than 10/100 mm x: greater than 10/100 mm (3) “Long” means exposure time longer than 150 seconds, and “less than 150 seconds” "Short".

[Example 1]
Liquid photosensitive resin APR (registered trademark) F-320 (manufactured by Asahi Kasei Chemicals Corporation) and F-330C (Asahi Kasei Chemicals Co., Ltd.) through a negative film and a cover film on a glass lower hard transparent substrate polished with high precision A photosensitive resin layer having a thickness of 5 mm (including a base film) is formed, and a polyester base film is overlaid thereon. Thereafter, the spacer height is increased by 0.1 mm, and a masking film having a thickness of 0.1 mm is overlaid (the state shown in FIG. 3). Then, an upper hard substrate made of Tempax glass polished with high accuracy was placed.

The distance between the two hard substrates was held by a spacer. Next, vacuum suction is performed from the upper and lower hard substrates, and after holding for 90 seconds while maintaining the adhesion of the negative film and the masking film, the mask is exposed for 60 seconds by irradiating active light through the upper transparent substrate and the masking film. It was. Thereafter, a relief exposure of irradiating active light through the lower transparent substrate and the negative film was performed for 130 seconds to complete the image forming exposure.
Next, the tourist layer thus exposed was washed out with a washing solution and developed according to a conventional method, followed by post-exposure in water and drying to obtain a printing plate having a plate thickness of 5 mm. The plate thickness accuracy ΔT of this plate is shown in Table 1.

[Example 2]
After laminating the photosensitive resin layer and the polyester base film by the same production method as in Example 1, a printing plate having a plate thickness of 5 mm was obtained under the condition that the spacer height was increased by 0.05 mm. The results are shown in Table 1.

[Comparative Example 1]
In Example 1, the plate was completely the same as Example 1 except that the upper transparent substrate was placed without changing the spacer height after laminating the photosensitive resin layer and the polyester base film (state of FIG. 4). A printing plate having a thickness of 5 mm was obtained. The results are shown in Table 1.

[Comparative Example 2]
In Example 1, after laminating the photosensitive resin layer and the polyester base film, the upper transparent substrate was placed without changing the spacer height, and then vacuum sucked from the upper and lower hard substrates to obtain the negative film and the masking film. A printing plate having a plate thickness of 5 mm was obtained in exactly the same manner as in Example 1, except that the adhesiveness was maintained for 180 seconds. The results are shown in Table 1.

  The present invention can be suitably used in the field of photosensitive resin plates for letterpress printing such as cardboard printing, film printing, preprint printing, and label printing.

It is a figure explaining the state which the bucket bottom part opens and is laminating. It is a figure explaining the state which has laminated | stacked the masking film after completion | finish of lamination. It is sectional drawing of the state before performing an exposure process in the state which increased the spacer height after laminating | stacking each layer by lamination etc. FIG. It is sectional drawing of the state before performing an exposure process in the state which laminated | stacked each layer by lamination etc. and did not change a spacer height. It is sectional drawing of the state which sandwiched each layer by the upper transparent substrate after laminating | stacking each layer, and finished relief exposure and masking exposure after that.

Explanation of symbols

1: Lower transparent substrate 2: Upper transparent substrate 3: Negative film 4: Cover film 5: Photosensitive resin layer 6: Base film 7: Masking film 8: Spacer 9: Upper lamp 10: Lower lamp 11: Bucket 12: Spacer height Liquid photosensitive resin layer laminated higher than

Claims (4)

  At least one of them is a transparent substrate, and a transparent film capable of transmitting active light is superimposed on at least one surface of a liquid photosensitive resin layer disposed between two supporting substrates, and image formation is performed by active light from one side or both sides. A method for producing a photosensitive resin plate for letterpress printing, which is subjected to development after exposure, wherein the two support substrates are formed after forming the liquid photosensitive resin layer, before image forming exposure, or during image forming exposure. A method for producing a photosensitive resin plate for letterpress printing, wherein the interval is increased within a range in contact with the upper support substrate.   The method for producing a photosensitive resin plate for letterpress printing according to claim 1, wherein the interval between the support substrates is increased by 0.05 mm or more and 0.5 mm or less.   The manufacturing method of the photosensitive resin plate for letterpress printing of Claim 1 which makes the space | interval of a support substrate increase 0.1 mm or more and 0.3 mm or less.   The manufacturing apparatus used for the manufacturing method of the photosensitive resin plate for letterpress printing in any one of Claim 1 to 3.