JP2000221664A - Production of resin printing plate for flexographic printing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a resin printing plate having a small shrinkage after a photomechanical process. SOLUTION: The top and main parts of an adhesive layer of a double-coated tape on one side of the base film are separately covered with releasing paper 6" and releasing paper 6. The top part of an adhesive layer on the other side of the base film is covered with releasing paper 6', the main part of the adhesive layer is bonded to a base plate and this base plate is stuck to a photosensitive resin printing plate to form a printing plate material not subjected to primary exposure. A negative is optionally put on the surface of the photosensitive resin printing plate, the surface is covered with a cover sheet, close contact is attained by evacuation and primary exposure is carried out to produce the objective resin printing plate for flexographic printing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a resin plate for flexographic printing.
The present invention relates to a method of manufacturing a resin plate for flexographic printing, in which a double-sided tape is attached to a laminated plate obtained by laminating a photosensitive resin plate and a base plate, and then vacuum-adhered to make a main exposure.

[0002]

2. Description of the Related Art A resin plate for flexographic printing includes (i) a photosensitive resin plate for flexographic printing and a rubber-based bonded plate (abbreviated as a rubber-based resin plate) and (ii) a photosensitive resin plate for flexographic printing. And a plastic resin-based bonded plate (abbreviated as resin-based resin plate). FIG. 1 shows the configuration of a rubber-based resin plate or the like at the time of main exposure after vacuum suction and close contact in the conventional method (hereinafter, vacuum suction and close contact are referred to as vacuum close-contact). FIG. 2 shows the configuration of the plate and the like.

Hereinafter, a method of manufacturing a plate material will be described with reference to FIG. 1 using a conventional rubber-based resin plate as an example. The photosensitive resin plate 4 for flexographic printing (hereinafter abbreviated as “resin plate”) 4 is made of, for example, a UV-curable resin such as a styrene-butadiene-styrene resin having a thickness of about 3 mm. It is cured to a thickness of about 1 mm (back exposure).
After bonding the cured surface of the resin plate 4 after the back exposure to the base plate 5, a negative 7 is superposed on the resin plate side of the obtained resin plate / base plate as necessary, and a cover sheet 8 is placed thereon. , Sucking in a vacuum and bringing the negative 7 into close contact with the resin plate surface,
The main exposure is performed by an ultraviolet lamp or the like. By the main exposure, a portion irradiated with light corresponding to the negative is cured, and a pattern is obtained. After the main exposure, the cover sheet 8 and the negative 7 are removed, and the resin plate / base plate is supported only on the top 20 of the base plate 5 via a double-sided tape (not shown). Glued to the part. The bonding width of the top 20 of the base plate is 5 to 10 cm. Normally, since the double-sided tape 2 is a double-sided tape having a pattern such as a groove for air release, the adhesive strength is poor, and the adhesive surface is treated with an acrylic primer, and then the double-sided tape is bonded. In addition to bonding with a tape, they were reinforced with a strong adhesive tape or the like. The obtained resin plate / base plate / support film is conveyed to a washing step by a pin / bar / chain, and after the uncured resin is washed out by the solvent, the support film (washing and conveying film) is removed. , Dried. Dried resin plate /
After the resin plate is finally cured by post-exposure, a post-treatment is performed to give the surface an appropriate roughness, and a plate material is obtained. For the plate material, the double-sided tape 2 is stuck on the entire surface of the base plate side and stuck on the carrier sheet for printing and then attached to the plate cylinder (indirect sticking) or directly stuck to the plate cylinder for printing (direct sticking) ) It is then ready for printing.

In the conventional method, the adhesion between the base plate and the double-sided tape is poor in the washing step. Therefore, the base plate is bonded with the double-sided tape and reinforced so as to be covered with a strong adhesive tape or the like. If the time becomes long, the gum tape may drop off in the middle or a part of the double-sided tape may be peeled off, resulting in a decrease in the quality of the plate material or a failure in use. In addition, when applying a double-sided tape to a carrier sheet for printing, applying a primer treatment may cause uneven thickness depending on the method of application, deteriorating printing accuracy, making it difficult to obtain clean printing, and Doing so reduced the efficiency of the plate-pasting operation.

[0005] When the base plate 5 is a polyester base, this poses no problem, but when the base plate 5 is a rubber base plate, the base cloth portion 9 inserted between the rubber layers has a function of maintaining the dimensions. But, depending on the solvent used at the time of washing,
The monomer and plasticizer in the resin plate were extracted, shrunk after drying, and the dimensional accuracy of the plate material was low.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a resin plate having a small expansion and contraction ratio after a plate making process, and to increase the adhesive strength between a support film head and a top of a double-sided tape adhered to a base plate. To make it difficult to peel off in the washing process, to obtain sufficient adhesive strength even if the primer treatment at the time of bonding to the carrier sheet is eliminated, and to eliminate the need for wiping the back surface of the plate material when used for printing, etc. The goal is to simplify the process.

[0007]

Means for Solving the Problems In the step before the main exposure, the present inventors adhered a double-sided tape to a resin plate / rubber base plate and then brought into close contact with the resin plate / rubber base plate to form a rubber base plate and a double-sided tape. The present inventors have found that such problems can be solved by enhancing the adhesion of the main part of the double-sided tape by the heat in the drying step, thereby completing the present invention.

That is, the first aspect of the present invention is that the top part (21) and the main part (3) of the adhesive layer (11) of the double-sided tape (2) are provided.
1) is covered with a release paper (6 ″) and a release paper (6), respectively. The adhesive layer (11) of the double-sided tape (2) and the adhesive layer (12) on the opposite side of the base film (10) are sandwiched. The top (22) is covered with a release paper (6 ') and the adhesive layer (1
The main part (32) of 2) is adhered to a base plate (5), and the base plate (5) is bonded to a photosensitive resin plate (4) so that a plate material (3) of non-primary exposure is formed. Then, a negative (7) is superposed on the surface of the photosensitive resin plate (4) as necessary, and a cover sheet (8) is put on the negative (7), and the main sheet is subjected to vacuum suction and adhered to perform main exposure. And a method for producing a resin plate for flexographic printing. The second aspect of the present invention is that the main portion (32) of the adhesive layer (12) is heated by heating after the main exposure.
A method for producing a resin plate for flexographic printing according to the first aspect of the present invention, wherein the method strengthens the adhesion between the resin plate and the base plate (5). A third aspect of the present invention provides the method for producing a resin plate for flexographic printing according to the first aspect of the present invention, wherein the base plate (5) is a rubber base or a polyester base. The fourth aspect of the present invention is to provide a base film (1
0) is a polyester film having a thickness of 25 to 100 μm, and the method for producing a resin plate for flexographic printing according to the first aspect of the present invention is provided. The fifth of the present invention
Provides a method for producing a resin plate for flexographic printing according to the first aspect of the present invention, wherein the pressure-sensitive adhesive layer is made of an acrylic or natural rubber.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 3 shows the structure of the cover sheet / negative / resin plate / base plate / double-sided tape at the time of vacuum suction before the main exposure in the present invention. The photosensitive resin plate 4 for flexographic printing (hereinafter abbreviated as "resin plate") 4 is made of, for example, a UV-curable resin such as a styrene-butadiene-styrene resin having a thickness of about 3 mm, and a back surface having a thickness of about 1 mm. Cure (back exposure).
The resin plate after the back exposure is bonded to the base plate 5. The double-sided tape 2 is laminated on the surface of the base plate 5 opposite to the surface on which the resin plate is bonded. The double-sided tape 2 has an adhesive layer 12 on the base plate 5 side and an adhesive layer 11 on the opposite side of the base film 10. The main part 32 of the adhesive layer 12 of the double-sided tape 2 is adhered to the base plate 5, and the top part 22 is covered with release paper 6 '. The adhesive layer 11 side of the double-sided tape 2 is the main part 31
There is a release paper 6 on the top, and a release paper 6 ″ on the top 21. A negative 7 is layered on the resin plate side of the resin plate / base plate / double-sided tape having such a configuration as necessary, and a cover sheet is placed thereon. 8 and then vacuum-adhered to form a double-sided tape 2
Is strongly adhered to the base plate 5, and the adhesive strength is also increased when the main exposure is performed by an ultraviolet lamp or the like. By the main exposure, the portion irradiated with light is cured, and a pattern corresponding to a negative is obtained. After the main exposure, the cover sheet 8 is removed, and if a negative is used, the negative 7 is also removed. The main exposure resin plate / base plate / double-sided tape to which the double-sided tape is strongly adhered is peeled off from the release paper at the top 6 ″ and attached to the head of a support film (not shown). After the uncured resin flows out by the solvent, the support film is removed and dried.
Since the adhesive strength of the double-sided tape is improved, there is no fear of peeling of the double-sided tape and the support film in the washing step. After drying the resin plate / base plate / support film, the resin plate is finally cured by post-exposure, and then subjected to a post-treatment for imparting appropriate roughness to the surface.

FIG. 4 shows the structure of the resin plate / base plate / double-sided tape after the post-treatment in the present invention. After the post-treatment, the resin plate / base plate / double-sided tape is bonded to the adhesive layer tops 21 and 22.
After trimming, the final finish is to prevent assault, trim for weight reduction and sealing of the peeling edge, then remove the release paper 6 and directly attach it to the plate cylinder for printing (directly The sheet is attached to a carrier sheet for printing (FIG. 5), or attached to a plate cylinder (indirect attachment (FIG. 6)), and then subjected to printing. In the present invention, the adhesion between the base plate and the double-sided tape at the top is strengthened mainly by the heat during the vacuum contact and the heat at the time of partial exposure, so that there is no need to perform a primer treatment or reinforce with a gum tape in advance. Also, the adhesive strength of the main part of the double-sided tape is improved by the heat during drying.

As the photosensitive resin plate 4 used in the present invention, a photosensitive resin plate of styrene-butadiene-styrene, styrene-isoprene-styrene, (meth) acrylic or the like can be used.

As the base plate 5 used in the present invention, a rubber base plate (referred to as a rubber base) or a resin base plate (referred to as a resin base) is used. Types of rubber-based rubber include natural rubber (NR), styrene-butadiene rubber (SBR), butadiene-acrylonitrile rubber (NBR), and chloroprene rubber (CR)
System, and the like. Rubber base thickness is 2-6mm
It is. The rubber base preferably has a base cloth 9 in the middle. Further, the rubber base preferably has a resin plate unnecessary for printing and a release layer for removing a rubber layer adhered to the resin plate. As the resin base, various conventional thermoplastics can be used, but polyester resins commercially available for flexographic printing are preferable.
The thickness of the resin base is 100 to 250 mm.

In the case of manufacturing a bonded plate of the photosensitive resin plate 4 and the rubber base plate, after the bonding is completed, the back surface is wiped off using a good solvent, and used for vacuum suction and main exposure.

The double-sided tape 2 used in the present invention includes:
One having adhesive layers 11 and 12 on both sides of a base film 10 is used. The base film 10 has a thickness of 25
Polyester films of １００100 μm are preferred. Examples of the material of the adhesive layer include acrylic, chloroprene rubber, styrene / butadiene rubber, and natural rubber, and preferably acrylic and natural rubber. When the double-sided tape 2 is bonded to the base 5, when the top is bonded to the support film, or when the main part is bonded to the plate cylinder or the carrier sheet, the double-sided tape 2 has a structure capable of bleeding air at the time of bonding. It is preferable that the adhesive layer is provided in a strip shape with an interval (producing a groove-shaped air vent), or the one provided with a pattern such as unevenness or embossing. The width of the tops 21 and 22 of the double-sided tape 2 is 5 to 10 cm and is adhered to the head of the support film 1.

The support film 1 used in the present invention preferably has good adhesiveness to the double-sided tape, has chemical resistance at the time of washing, and does not easily expand and contract. As the support film 1, a polyester film having a thickness of 100 to 300 μm can be used.
Alternatively, a polyester film of 250 μm is preferable.

As the cover sheet 8 used in the present invention, a cover sheet which is sufficiently transparent to ultraviolet rays for exposure or the like and is hardly deteriorated is preferable, and examples thereof include a polyvinyl chloride film.

The plate material manufacturing apparatus used in the present invention includes:
An apparatus capable of performing a vacuum adhesion step, an exposure step, a washing step, a drying step, and a finishing step can be used.

In the vacuum contact step, the inside of the apparatus is 50 to 7
Since the pressure is reduced to 0 cmHg, atmospheric pressure is applied on the cover sheet, and the resin plate / base plate / double-sided tape covered with the cover sheet is pressed by atmospheric pressure, and the double-sided tape and the base plate are strongly bonded. The adhesive strength between the double-sided tape and the base plate is 1.5 kg / 3 cm width or more, preferably 2.
0 kg / 3 cm width or more.

The exposure step is carried out by irradiating ultraviolet rays, X-rays, γ-rays, electron beams or the like, but preferably ultraviolet rays are used. As a lamp for irradiation, a high-pressure and / or low-pressure mercury lamp or the like can be used. Back exposure, main exposure, and post-exposure can be performed by selecting the wavelength of the lamp using the same apparatus. When the main exposure is performed in a state of being in close contact with a vacuum, heat from an ultraviolet lamp or the like further increases the adhesive strength of the double-sided tape.

In the washing step, the photosensitive resin in the non-mainly exposed portion corresponding to the non-image portion is washed out. The solvent used in the washing step is selected depending on the type of the photosensitive resin. For example, an acid group-containing water-soluble polymer is dissolved and washed with an alkaline aqueous solvent, and a non-water-soluble polymer is dissolved and washed with an organic solvent.

In the drying step, the washed resin plate / base plate / double-sided tape is heated and dried. The heating conditions are 40 to 60 ° C. for 0.5 to 2.0 hours, preferably 5 to 2.0 hours.
0.5-1.0 hour at 0-55 ° C. The adhesion between the main portion 32 of the adhesive layer 12 and the base plate 5 can also be enhanced by heating. The adhesive strength between the main part of the double-sided tape and the base plate is 2.0 kg / 3 cm width or more, and preferably 2.5 to 4.0 kg / 3 cm width.

In the finishing step, the surface is tackified by post-exposure, the surface is given a roughness to improve ink acceptance and transferability, and the final exposure improves the strength of the photosensitive resin in the image area. .

After the finishing step, the top of the pressure-sensitive adhesive tape is cut off, trimmed for the final finishing to prevent the assembling, weight reduction, and sealing of the peeled edge.
Remove the release paper of the main part 31 of FIG. 1 and adhere it to the plate cylinder in the case of direct application, and attach it to the plate cylinder with a jig in the case of indirect application in a jig, and supply each for printing. Is done.

The printing ink is not particularly limited, and a mixed solvent-based ink containing a water, alcohol or glycol-based flexo ink and a surfactant, and a UV ink can be used.

The resin plate for flexographic printing obtained by the present invention has good dimensional accuracy and is mainly used for cardboard, heavy bags, soft packaging, beverage cartons, seal labels, envelopes and the like.

[0026]

EXAMPLES The present invention will now be described specifically with reference to examples, but the present invention is not limited to these examples. The adhesive strength was measured at a peeling rate of 180 degrees and a descent speed of 300 mm / min. The shrinkage rate was indicated by the average value of the vertical and horizontal shrinkage rates of a 500 mm × 500 mm plate material. In addition, the thing of the same size as the negative is assumed to have a shrinkage of 0%.

[Example 1] Photosensitive resin plate: MC plate MDR type (manufactured by DuPont) Rubber base: MC base thickness 7.0 mm (manufactured by Meiwa Rubber Industry Co., Ltd.) Double-sided tape (1) : Acrylic resin 535F (manufactured by Nitto Denko Corporation). It has a thickness of 110 μm / containing a polyester base material (thickness of 25 μm), and the adhesive layer is applied in a strip shape at regular intervals to release air. Double-sided tape (2): Acrylic resin type 213T (manufactured by Kyodo Giken Co., Ltd.). Contains 110 μm thickness / polyester base material (25 μm thickness), and has an embossed net-like adhesive layer for air release. Double-sided tape (3): Natural rubber Y447 (manufactured by Sumitomo 3M Limited). It has a thickness of 110 μm / containing polyester base material (thickness of 25 μm), and the adhesive layer has no pattern. Plate making machine Exposure machine: JE-1800-3H (manufactured by JEOL Ltd.), UV lamp: using Sankyo Denki HP360, output 4
0W Washing machine: 2001P (manufactured by Dupont) Drying machine: 3002D (manufactured by Dupont) A double-sided tape is attached to the rubber base of the laminated plate obtained by laminating the photosensitive resin plate to the rubber base. Wearing. The other side of the double-sided tape is covered with release paper. The top of the double-sided tape is provided with a width of 5 cm for fixing to the washing machine. A cover sheet was put on the double-sided tape-attached plate, and was vacuum-adhered at 55 cmHg for 12 minutes by an exposure machine to perform main exposure. At this time, double-sided tape is 40
Heated to ° C. After the main exposure, the release paper at the top with a width of 5 cm for fixing to the washing machine was peeled off, and the thickness was 188 μm.
After bonding to the head of a polyester support film, the solvent (tetrachloroethylene: isopropanol =
85: 15% by volume) for 4 minutes and 50
C. and dried for 30 minutes. The adhesive strength between the rubber base and the double-sided tape was measured 5 minutes after the end of the main exposure, and 10 minutes and 60 minutes after the end of plate making, and the shrinkage ratio was measured 1 hour and 12 hours after plate making. Table 1 shows the results. After the above-described plate making, the release paper on the double-sided tape side was peeled off, attached to a carrier sheet, attached to a plate cylinder, and used for printing.

[Comparative Example 1] A case where a double-sided tape was applied after the main exposure was completed using a bonded plate obtained by bonding a photosensitive resin plate to the same rubber base as in Example 1 and a double-sided tape for washing out. The adhesive strength between the rubber base and the double-sided tape, and the adhesive strength and shrinkage ratio between the rubber base and the double-sided tape when a double-sided tape for pasting was applied to the carrier sheet after the completion of plate making, as in Example 1. Was measured. Table 1 shows the results.

[0029]

[Table 1]

Example 2 Photosensitive resin plate: TDR-T100 type (manufactured by DuPont) Resin base: 125 μm thick polyester (manufactured by DuPont) The above photosensitive resin plate and resin base Are united. Using the integrated photosensitive resin plate / resin base, a double-sided tape was adhered in the same manner as in Example 1, and the main exposure was performed by vacuum adhesion at 55 cmHg for 20 minutes. At this time, the double-sided tape was heated to 42 ° C. After the main exposure, the release paper at the top having a width of 5 cm for fixing to the washing machine was peeled off in the same manner as in Example 1, and the thickness was 188 μm.
After bonding to the head of a polyester support film, the solvent (tetrachloroethylene: isopropanol =
85: 15% by volume) for 4 minutes and 50
C. and dried for 30 minutes. The adhesive strength between the polyester base and the double-sided tape was measured 5 minutes after the main exposure, and 10 minutes and 60 minutes after the plate making. Table 2 shows the results.
The release paper on the double-sided tape side of the plate making was peeled off and directly attached to the plate cylinder surface, and used for printing.

Comparative Example 2 Using the same photosensitive resin plate / resin base as in Example 2 and a double-sided tape for washing out, a polyester base obtained by attaching the double-sided tape after the main exposure was completed. The adhesive strength between the double-sided tape and the adhesive strength between the polyester base and the double-sided tape when the double-sided tape was stuck after the plate making was measured in the same manner as in Example 2. Table 2 shows the results.

[0032]

[Table 2]

[0033]

According to the present invention, the adhesive strength between the double-sided tape and the laminating plate is greatly increased, and there is no need to reinforce the top of the double-sided tape with a gum tape or the like. became. Also, since it is attached to the base plate using a double-sided tape having a polyester base material, shrinkage due to extraction of monomers and plasticizers inside the resin plate in the washing step and the drying step is suppressed, and the obtained plate material is The dimensional accuracy has been greatly increased. Also, when fixing the plate material to the plate cylinder or carrier sheet during printing, the release paper is peeled off and fixed, so there is no need to wipe off the dirt on the base plate during the plate making process again, and no primer treatment is required Became.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing the configuration of a conventional method, such as a vacuum-adhesion method, a laminated plate of a photosensitive resin plate and a rubber base plate at the time of main exposure, and the like.

FIG. 2 is a cross-sectional view showing the configuration of a conventional method, such as a vacuum-adhesion and a laminated plate of a photosensitive resin plate and a resin base plate at the time of main exposure.

FIG. 3 is a cross-sectional view showing a structure of a laminated plate of a photosensitive resin plate and a rubber base plate at the time of vacuum adhesion and main exposure in the present invention.

FIG. 4 shows the resin plate / base plate /
It is sectional drawing which shows the structure of a double-sided tape.

FIG. 5 is a cross-sectional view showing a relationship between a plate cylinder and a resin plate for flexographic printing directly adhered thereon for printing in the present invention.

FIG. 6 is a cross-sectional view showing the relationship between a plate cylinder and a resin plate for flexographic printing which is indirectly affixed thereto via a carrier sheet for printing in the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Support film 2 Double-sided tape 3 Plate material 4 Photosensitive resin plate 5 Base plate 6 Release paper 6 'Release paper 6 "Release paper 7 Negative 8 Cover sheet 9 Base cloth 10 Base film 11 Adhesive layer 12 Adhesive layer 21, 22 Top 31, 32 Main part 50 Plate cylinder 60 Carrier sheet

 ──────────────────────────────────────────────────続 き Continued on front page F term (reference) 2H025 AB02 AC01 AD01 BD43 BD47 FA16 2H096 AA02 BA06 EA02 EA30 GA04 2H114 AA01 AA23 BA01 DA46 DA52 DA56 GA38

Claims (5)

[Claims] 1. A top part (21) and a main part (31) of an adhesive layer (11) of a double-sided tape (2) are each made of release paper (6 ″).
And a top portion (22) of the adhesive layer (12) opposite to the adhesive layer (11) of the double-sided tape (2) and the base film (10), and covered with the release paper (6 ′). ), The main part (32) of the adhesive layer (12) is adhered to the base plate (5), and the base plate (5) is bonded to the photosensitive resin plate (4) to form a non-primary exposed plate material ( A negative (7) is stacked on the surface of the photosensitive resin plate (4) as necessary so that 3) is formed, and a cover sheet (8) is placed on the negative (7).
A method for producing a resin plate for flexographic printing, wherein the main plate is exposed by vacuum suction. 2. The flexo according to claim 1, wherein after the main exposure, heating is applied to strengthen the adhesion between the main part (32) of the adhesive layer (12) and the base plate (5). Manufacturing method of printing resin plate. 3. The method for producing a resin plate for flexographic printing according to claim 1, wherein the base plate (5) is a rubber base or a polyester base. 4. The base film (10) has a thickness of 25 to 1
The method for producing a resin plate for flexographic printing according to claim 1, wherein the resin plate is a 00 μm polyester film. 5. The method for producing a resin plate for flexographic printing according to claim 1, wherein the adhesive layer is made of an acrylic or natural rubber.