JPH0880688A - Bonding sheet for temporarily bonding flexographic printing plate - Google Patents

Abstract

PURPOSE: To prevent the generation of an air sump when a flexographic printing plate is bonded to hold uniform thickness by providing a foamed resin layer wherein air bubbles are continued by mutual air bubbles or a surface space and fine ducts to the single surface of a support. CONSTITUTION: A foamed resin layer 11 is formed on the single surface of a support 10 composed of a polyester film so that a large number of air bubbles are present in the foamed resin layer 11 and continued by other adjacent air bubbles and a surface space and fine ducts to be uniformly distributed. A polyethylene film is laminated on the foamed resin layer 11 as a protective layer 12 and a self-adhesive is applied to the other surface of the support 10 to form a self-adhesive layer 13. Release paper is laminated on the self-adhesive layer 13 as a release layer 14 to obtain a bonding sheet 1A for temporarily bonding a flexographic printing plate. After the release layer 4 is peeled, the sheet 1A is gradually bonded to the rear surface of the flexographic printing plate while lightly rubbed and pressed so as not to generate wrinkles. After the protective layer 12 is peeled, the flexographic printing plate is positioned to closely bond the bonding sheet 1A to a plate cylinder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexographic plate temporary adhesion sheet for tightly adhering a flexographic plate to a plate cylinder, a carrier sheet or a sleeve.

[0002]

2. Description of the Related Art In conventional flexographic printing, as a method for mounting a flexographic plate on a plate cylinder of a printing machine, the following two methods are generally used.
There are two ways. (A) Method of aligning the flexographic plate using a sticking proofing machine and directly sticking the flexographic plate to the plate cylinder of the printing machine (b) To a plastic sheet made of polyamide, polyester, etc. (called a carrier sheet) The method of attaching the flexo plate to the plate cylinder by using the clamp etc. after the flexo plate pasting position is stated in advance and the flexo plate is pasted at that position. In the above method (a), the flexo plate is pasted. As the above, sticking with a double-sided pressure-sensitive adhesive sheet was used, and in the method (b), bonding with an adhesive or sticking with a double-sided pressure-sensitive adhesive sheet was used.

In recent years, the number of prints required for printing accuracy and multicolored prints has increased, and there is a tendency for further improvement in finish quality to be required. Therefore, the thickness accuracy of the flexo plate mounted on the plate cylinder and the positioning accuracy of each flexo plate in multicolor printing are being demanded more severely. However, when the flexographic plate is attached to the carrier sheet with an adhesive, it is difficult to apply the adhesive uniformly,
The adhesive strength may be non-uniform, or the thickness accuracy after sticking may not be obtained. Furthermore, even if a displacement occurs during alignment, the use of double-sided pressure-sensitive adhesive sheets instead of adhesives tends to increase because, for example, they cannot be re-attached after they are completely bonded.

However, when the flexographic plate is stuck with the double-sided pressure-sensitive adhesive sheet, air is not caught in the bonding surface between the flexographic plate and the double-sided pressure-sensitive adhesive sheet and the bonding surface between the double-sided pressure-sensitive adhesive sheet and the plate cylinder or the carrier sheet. There is a problem in that air liquor is likely to occur when it gets up and thickness accuracy is difficult to obtain. In general, if air pockets occur on the surface that was first applied, you can pierce the pin from the opposite surface of the double-sided PSA sheet to remove air from the pin holes, but then when you attach the opposite surface, air will be removed. When a puddle was formed, the pin could not be pierced, and the air puddle was removed by reattaching. Further, when the air pool was small, it was crushed with a finger and diffused, but the temporarily diffused air was liable to concentrate on a portion having a weak adhesive force, and sometimes existed as an air pool during the printing operation.

Further, in the re-adhesion work performed when an air pocket is generated or when the position is corrected, the flexographic plate is difficult to peel off from the plate cylinder or the carrier sheet, and the adhesive remains on the attaching surface. In some cases, there is a problem in that it is necessary to remove the remaining adhesive from the sticking surface.

When the flexographic plate is directly stuck to the plate cylinder, the flexo plate is generally stuck to the plate cylinder to which the double-sided pressure-sensitive adhesive sheet has been stuck in advance due to the work of the sticking proof machine, so that the printing work is completed. In that case, the flexographic plate must be peeled off from the double-sided adhesive sheet and stored. At that time, if an excessive peeling force is applied, the flexographic plate may be distorted or a fine pattern may be destroyed.

Further, when a flexo plate is attached to a carrier sheet using a thick double-sided pressure-sensitive adhesive sheet having a foam layer having cushioning properties laminated, since the work of attaching the flexo plate is performed on a flat surface, When the carrier sheet is mounted on the plate cylinder, there is a difference in the curvature radius between the flexo plate and the carrier sheet, which causes slack in the carrier sheet, and the flexo plate is pulled in the circumferential direction of the plate cylinder to cause slight distortion. However, there is a problem that the foam layer is refracted and air bubbles are generated. Further, in the conventional double-sided pressure-sensitive adhesive sheet laminated with a foam layer, it is difficult to peel it off because the adhesive strength is strong, and the double-sided pressure-sensitive adhesive sheet is re-attached on the plate cylinder, and the slack of the carrier sheet, the slight distortion of the flexo plate,
The air pocket due to the refraction of the foam could not be removed.

Further, in flexographic printing, which requires a higher printing accuracy, finer patterns can be obtained by using a relatively thin flexo plate, so that the thin flexo plate tends to increase, resulting in more uniform printing. Thickness accuracy and appropriate cushioning are required.

As a means for solving the above-mentioned problems, there is a fixing sheet 100 for a printing plate proposed in Japanese Patent Laid-Open No. 3-331152. As shown in FIG. 21, the fixing sheet has pressure-sensitive adhesive layers 102 and 104 on both sides of a support body 101, and exhaust paths 103 and 105 for air trapped in the sticking surface are provided. It is characterized by that. When the flexographic plate is attached to the carrier sheet with the fixing sheet, no air pocket is generated. However, by repeating re-adhesion, the adhesive strength decreases,
The adhesive surface becomes rough.

Even when a flexographic plate is directly printed on the plate cylinder by using the fixing sheet for printing, or when it is printed by being stuck on a carrier sheet, an ordering cycle until printing of a wide variety of products or the next printing is performed. For a long period of time, the flexographic plate is once peeled off and stored, but the fixing sheet cannot be reused due to the roughening of the pressure-sensitive adhesive surface or the deterioration of the adhesive force, and the fixing sheet is required each time printing is performed. Must be pasted. Further, since a large peeling force is required at the time of re-adhesion, workability is poor, and there is a problem that the flexographic plate is distorted or a fine pattern is destroyed.

As another solution, Japanese Patent Laid-Open No. 5-2460
There is a double-sided pressure-sensitive adhesive tape 110 for flexographic plate fixing proposed in Japanese Patent No. As shown in FIG. 22, the double-sided pressure-sensitive adhesive tape for fixing a flexographic plate has a first adhesive layer 112 for sticking a flexographic plate on one surface of a support 111 and a carrier sheet for sticking a carrier sheet on the other surface. The second pressure-sensitive adhesive layer 113 is formed, the pressure-sensitive adhesive force of the first pressure-sensitive adhesive layer is made larger than the pressure-sensitive adhesive force of the second pressure-sensitive adhesive layer, and further penetrates from the first pressure-sensitive adhesive layer to the second pressure-sensitive adhesive layer. A large number of holes 114 are formed.
When the flexographic plate is attached to the carrier sheet using the double-sided pressure-sensitive adhesive tape for fixing the flexographic plate, no air pocket is generated.
However, there were problems that the adhesive surfaces contacted with each other and the adhesive surface was roughened during repeated re-adhesion work, and there was almost no cushioning property.

Further, if an adhesive having a weaker adhesive force is used for the second adhesive layer of the double-sided pressure-sensitive adhesive tape for fixing a flexographic plate, it is expected that the adhesive will be easily peeled off and the re-adhesion work will be facilitated. However, adhesives with weak adhesive strength
Since the adhesive strength varies greatly depending on the surface condition when pressing and the pressing pressure, in order to prevent the flexo plate from coming off during printing, in consideration of safety, use the 180 ° peeling method for the stainless steel plate. 300 g / in adhesive strength
It is preferable that the thickness is 20 mm or more, and the re-adhesion work cannot be greatly improved.

Further, as another means for solving the problem, the actual exploitation Sho 63
There is an adhesive tape 120 for fixing a printing plate, which is proposed in Japanese Patent Publication No. 21058. The plate fixing adhesive tape is shown in FIG.
As shown in FIG. 3, one side of the foam substrate 121 has a tensile strength of 10
A plastic film 122 having a Kg / mm ² or more and an elongation of 10 to 200% is laminated, and the pressure-sensitive adhesive layer 1 is further provided on both sides thereof.
23 is laminated. When the flexographic plate is attached to the plate cylinder using the pressure-sensitive adhesive tape for fixing the plate, an appropriate cushioning property is obtained due to the elasticity of the foam substrate, and the foam substrate is reinforced by laminating the plastic film. When the flexographic plate is peeled off from the cylinder, the foamed substrate is not destroyed and remains on the plate cylinder surface. Further, the pressure-sensitive adhesive layer directly laminated on the foamed substrate is unlikely to cause air pockets when it is attached.

However, the pressure-sensitive adhesive layer directly laminated on the plastic film tends to cause air pockets when it is attached. In addition, a large peeling force is required at the time of re-adhesion, resulting in poor workability. In addition, the printing plate fixing adhesive tape that was used once is
It cannot be reused at the next printing. Furthermore, when a flexographic plate is attached to a carrier sheet using the printing plate fixing adhesive tape, due to the difference in the radius of curvature between the flexographic plate and the carrier sheet, the slack of the carrier sheet, the slight distortion of the flexographic plate, the foam substrate There is a problem that air bubbles are generated due to refraction.

As a mounting method other than the above (a) and (b), a flexographic plate is stuck to a sleeve formed by molding reinforced plastic into a cylindrical shape by using a sticking calibrator, and then the sleeve is mounted on the plate cylinder. A method of fitting and mounting has been proposed. However, since the double-sided pressure-sensitive adhesive sheet is used as a means for sticking the flexographic plate to the sleeve, the same problem as in the case of directly sticking it to the plate cylinder has also occurred in the mounting method.

Further, as another mounting method, there is proposed a method in which a plastic magnet sheet having a thickness of 0.4 to 1.5 mm is adhered to a flexographic plate with an adhesive or a double-sided adhesive tape, and is directly adsorbed on the plate cylinder. Has been done. However, the specific gravity of the plastic magnet sheet is 3.5 to 3.9, and when it is attached to the flexographic plate, it becomes considerably heavy and the workability deteriorates. Also, when a flexographic plate with a magnet sheet is brought close to the plate cylinder, the magnetic force attracts the flexo plate to the plate cylinder, making it difficult to align the position. Also,
Depending on the working environment, the metal powder is adsorbed on the adsorbing surface of the magnet sheet, and it is difficult to remove the metal powder. Further, the flexographic plate is stretched in the circumferential direction of the plate cylinder due to the difference in radius of curvature between the attracting surface of the magnet sheet and the flexographic plate surface. Or, if you attach the flexo plate to the magnet sheet that is pre-adsorbed on the plate cylinder,
When peeled off from the plate cylinder, there was a problem that the flexo plate remained rounded due to the difference in curvature radius and was difficult to store.

[0017]

SUMMARY OF THE INVENTION The present invention has been made in view of such problems of the prior art, and an object thereof is to apply a flexographic plate to a plate cylinder, a carrier sheet or a sleeve. When sticking, it has a uniform thickness without air pockets. Also,
Proper cushioning is obtained. Further, when the flexographic plate is peeled off, it can be peeled off without applying an excessive peeling force, and the flexo plate and the contact surface are not damaged. Furthermore, it is an object of the present invention to provide a contact sheet for flexographic plate temporary fixing, which has good workability in positioning and can be easily reattached.

[0018]

A contact sheet for flexographic printing plate temporary fixing according to claim 1 comprises: (A) a support made of a plastic film; (B) a large number of air bubbles provided on one side of the support. And the bubbles are provided on the other surface of the foamed resin layer (C) on the foamed resin layer (C) on the other side of the support, which is continuous with other air bubbles and / or surface spaces adjacent to each other by fine conduits. A laminate comprising an adhesive layer and (E) a release layer on the adhesive layer.

An adhesion sheet for flexographic plate temporary fixing according to claim 2 is characterized in that, in the laminate according to claim 1, a large number of holes are provided to allow ventilation from the adhesive layer to the foamed resin layer. .

The adhesion sheet for temporary fixing of flexographic printing plate according to claim 3 is the laminated body according to claim 1, wherein the adhesive layer is applied on the convex portions coated with the adhesive and thinner than the convex portions. Or a pressure-sensitive adhesive layer comprising concave portions which are not applied at all.

By the above, the above-mentioned object is achieved. The present invention will be described in detail below. The contact sheet for flexographic plate temporary fixing according to claim 1 is a laminated body as shown in FIG. As the support made of a plastic film, a plastic film of polyester, polyamide or the like having a thickness of 20 to 200 μm can be used. A polyester film having excellent dimensional stability and rigidity is preferable.

The foamed resin layer provided on one surface of the support has a large number of air bubbles inside, and these air bubbles are continuous with other air bubbles and / or surface spaces adjacent to each other by a fine conduit.
For example, the foamed sheet proposed in Japanese Patent Laid-Open No. 1-259043 can be used. The foamed sheet has adhesiveness and removability, and is formed by applying the foamed emulsion with a coating machine such as a comma coater or knife coater and then drying it with hot air at 100 to 160 ° C. The thickness of the foamed resin layer is preferably in the range of 200 to 1000 μm.

For the protective layer on the foamed resin layer, a known plastic film such as polyethylene, polypropylene, or polyvinyl chloride, or a release paper for a commonly used adhesive can be used.

The adhesive layer provided on the other surface of the support is
A rubber adhesive or a resin adhesive can be used. The pressure-sensitive adhesive layer has a thickness of 20 to 200 μm, and has a pressure sensitive adhesive force of 400 to 25 due to the 180 ° peeling method for a stainless steel plate.
It is preferably 00 g / 20 mm.

For the release layer on the pressure-sensitive adhesive layer, generally used release paper or release film for pressure-sensitive adhesive can be used.

As shown in FIG. 2, a large number of holes for venting from the pressure-sensitive adhesive layer to the foamed resin layer side are formed by laminating a peeling layer and a protective layer and then using a rotary die cutter or a puncher. Then, a hole penetrating from the peeling layer to the protective layer can be provided. Alternatively, as shown in FIG. 3, a needle-shaped pin having a sharp tip may be used to pierce the peeling layer so that the pin tip reaches the protective layer to form a hole. In that case, even if the tip of the pin reaches the surface of the foamed resin, the hole on the surface of the foamed resin contracts due to the elasticity of the foamed resin layer, and therefore the hole can hardly be visually confirmed.

Further, since the foamed resin layer has air permeability because the fine conduits communicating with the surface thereof and the bubbles inside are continuous with each other, if a hole penetrating the pressure-sensitive adhesive layer and the support is formed, The air trapped on the attachment surface is exhausted to the outside through the through hole and the foamed resin layer. Therefore, the foamed resin layer and the pressure-sensitive adhesive layer may be laminated on a support body having holes previously formed with a rotary die cutter or a puncher. In that case, depending on the size and shape of the pores, the thickness of the foamed resin layer, the viscosity at the time of applying the foamed emulsion, etc., the foamed resin layer may be entirely coated as shown in FIG. 4 or the pores as shown in FIG. It may not be applied.

Although the shape of the hole is not particularly limited,
In terms of manufacturing, as shown in FIGS. 6 and 7, it is preferable that they are circular and provided at a constant pitch. For example, in the case of a circular shape, it is preferable that the diameter is 0.05 to 3 mm and the pitch is 2 to 30 mm. The hole having a diameter of 0.05 to 1 mm can be formed by using a needle pin having a sharp tip. Further, the hole having a diameter of 1 to 3 mm can be provided by forming a hole penetrating from the peeling layer to the protective layer using a rotary die cutter or a puncher. Further, in the case of a hole having a diameter of 0.5 to 3 mm, a method of laminating a foamed resin layer and a pressure-sensitive adhesive layer on a support body having a hole previously formed by using a rotary die cutter or a puncher can be used.

The pressure-sensitive adhesive layer provided on the other surface of the support according to claim 3 and having a convex portion coated with a pressure-sensitive adhesive and a concave portion coated thinner than the convex portion or not coated at all. A rubber-based adhesive or a resin-based adhesive can be used. The pressure-sensitive adhesive layer has a thickness of 20 to 200 μm, and has an adhesive force of 400 to 2 by a 180 ° peeling method with respect to a stainless steel plate.
It is preferably 500 g / 20 mm. The uneven structure of the pressure-sensitive adhesive layer may be a striped structure as shown in FIG. 10, a grid-like structure as shown in FIG. 11, a spot-like structure as shown in FIG. , The recess is continuous. The concave portion may be formed in a state where a part of the surface of the pressure-sensitive adhesive layer is scraped off as shown in FIG. 8, that is, in a state of being applied thinner than the convex portion, or as shown in FIG. 9, it is not applied at all. You may form in a state. Further, the uneven structure of the pressure-sensitive adhesive layer can be formed by a method of pattern-coating the pressure-sensitive adhesive or a method of filling the pressure-sensitive adhesive in a mold corresponding to the uneven structure and then transferring the pressure-sensitive adhesive to the support. In general,
The size of the convex portion is preferably 1 to 100 mm based on the width or diameter, and the width of the concave portion is preferably 0.1 to 5 mm.

When a flexographic plate is stuck using the adhesion sheet for temporary fixing of flexographic plate according to any one of claims 1 to 3, the following procedure can be mentioned, for example. (When the flexographic plate is attached to the plate cylinder or sleeve: see FIGS. 13, 14 and 15) The size of the flexo plate having the protruding portion 40 of a required length from both edges in the plate cylinder circumferential direction (Y direction). Then, the adhesion sheet for temporary fixing of flexo plate is cut. Next, the release layer is peeled off, and the protruding portions are arranged at both ends in the Y direction of the flexo plate temporary adhesion adhesive sheet,
The adhesive layer and the back side of the flexographic plate are attached. Next, after the protective layer is peeled off, the flexographic printing plate is attached to the printing cylinder, the foaming resin layer is brought into close contact with the printing drum or the sleeve, and the flexographic printing plate is temporarily fixed. Further, the protruding portion is fixed to the plate cylinder or sleeve with the adhesive tape 41, and the flexographic plate is attached.

(When a flexographic plate is attached to a carrier sheet: see FIGS. 16, 17, 18 and 19) Four directions of the flexographic plate in the plate cylinder circumferential direction (Y direction) and the plate cylinder axial direction (X direction). A protruding portion 50 of a required length from the edge,
The adhesion sheet for temporary fixing of flexographic plate is cut into a size having 51. Then, the release layer is peeled off, and the pressure-sensitive adhesive layer and the back surface of the flexographic plate are attached at the positions where the protruding portions are arranged at the four ends in the Y direction and the X direction of the adhesion sheet for flexographic plate temporary fixing. Next, after peeling off the protective layer, the attachment positions of the flexographic plates are aligned, the foamed resin layer is brought into close contact with the carrier sheet, and the flexographic plates are temporarily fixed. Next, the central portion 5 in the Y direction of the protruding portion at the end in the X direction
2 is fixed to the carrier sheet with an adhesive tape 53 having an arbitrary length. Next, after the carrier sheet is hung on a clamp of the plate cylinder, the flexographic plate temporary fixing adhesive sheet is peeled from both end portions in the Y direction, and is re-attached, leaving the fixed central portion in the Y direction. Next, the protruding portions 50 at both ends in the Y direction are fixed to the carrier sheet with an adhesive tape, and the flexographic plate is attached to the carrier sheet. Further, the clamp etc. of the plate cylinder are tightened, and the carrier sheet is attached to the plate cylinder.

In the above-mentioned procedure for sticking the flexographic plate, it is preferable in terms of work that the required length of the protruding portion is at least half the width of the adhesive tape. After sticking the adhesive layer and the back side of the flexo plate, even if a plastic film or paper is stuck to the protruding part after sticking the flexo plate, in order to nullify the adhesive force of the adhesive layer on the protruding part. Good.

Further, after the carrier sheet is temporarily fixed to the plate cylinder, if there is no working area for reattaching the flexo plate temporary adhesion contact sheet, the above-mentioned curved surface having the same radius as the plate cylinder is used. After carrying out the re-adhesion work, the carrier sheet may be attached to the plate cylinder. For a curved surface having a radius similar to that of the plate cylinder, for example, a stainless steel pipe for piping (outer diameter: up to 3
00 mm) or arc-welded large-diameter stainless steel pipe for pipes (outer diameter: 350 to 1000 mm) can be used.

[0034]

The operation of the adhesion sheet for flexographic plate temporary fixing according to the present invention will be described below. The support imparts rigidity to the adhesion sheet for temporary fixing of flexographic plate, prevents the adhesion sheet for temporary fixing of flexographic plate from expanding and contracting during the attaching work, and does not cause variations in thickness and adhesion. Further, it is possible to prevent the foamed resin layer from being broken during the peeling work.

The foamed resin layer has adhesiveness and removability, and effectively acts on the smooth surface of the plate cylinder, carrier sheet and the like. It is considered that the action is manifested when the bubble structure inside the foamed resin and the appropriate elasticity of the foamed resin give a suction effect to the fine conduits communicating with the surface of the foamed resin, and combine with the smooth surface. In addition, the sucker effect is affected even if oil films such as silicone oil, machine oil, emulsifiers, etc., or water films, which generally inhibit adhesion or adhesion, are attached to the smooth surface of the plate cylinder or carrier sheet. The foamed resin layer retains good adhesion and removability.

When the flexographic plate is attached, the adhesion sheet for temporary fixing of the flexographic plate has an adhesiveness of the foamed resin layer of 5 to 50 g / 20 mm by the 90 ° peeling method with respect to the stainless steel plate and the plastic film. Since it is much weaker than general adhesives and has removability, it has a temporary fixing function to the plate cylinder or carrier sheet. In addition, the shear adhesive strength to the stainless steel plate is 0.8 to 1.5 kg / 4 cm ² , and when the surface of the foamed resin is in close contact, the flexographic plate does not shift and also has a position fixing function. Further, since the adhesiveness when the foamed resin surfaces are in contact with each other is weaker than the adhesiveness to the smooth surface, it can be easily peeled off and the foamed resin surface is not roughened. Due to these reasons, when the position of the flexographic plate is corrected, the re-pasting work can be easily performed.

When the surface of the foamed resin is brought into close contact with the surface of the plate cylinder, the carrier sheet or the sleeve, a non-adhered portion such as a so-called air pocket does not occur, so that the flexographic plate attached has a uniform thickness. To do. Further, the elasticity of the foamed resin layer gives the flexographic plate an appropriate cushioning property during printing. For these reasons, printing with the flexographic printing plate attached in the above procedure can prevent the occurrence of printing defects such as uneven printing, blurring, and blurring, and enables flexographic printing with high finishing accuracy.

The protective layer protects the surface of the foamed resin just before use and is peeled off when used. Also,
After printing, the flexographic plate is peeled off together with the flexo plate temporary adhesion adhesive sheet and stored with the protective layer laminated, so that the foamed resin surface is kept in a good state.

The adhesive layer is attached to the back surface of the flexographic plate. At that time, a large number of holes ventilated from the adhesive layer to the foamed resin layer act as exhaust holes for the air caught in the adhesive surface. Further, the concave portion formed on the adhesive layer with the adhesive thinner than the convex portion or not coated at all functions as an exhaust path for the air caught in the sticking surface.

When sticking the flexographic plate and the pressure-sensitive adhesive layer,
If you flexibly stick the flexo plate or the adhesion sheet for temporary flexo plate temporary holding while gently stroking it so that it does not wrinkle, air will be exhausted to the outside from the exhaust hole or exhaust path, so you will not entrap air . Also, air may be trapped inside the sticking surface at the time of sticking depending on the setting of the exhaust hole diameter and drilling density, or the setting of the exhaust passage width and spacing. Air is easily exhausted by pressing down.

The peeling layer protects the surface of the pressure-sensitive adhesive layer until just before use and is peeled off before use.

After the flexographic plate is temporarily fixed to the plate cylinder or sleeve, the protruding portions at both ends in the Y direction of the flexographic plate temporary adhesion sheet are fixed to the plate cylinder or sleeve with adhesive tape so that centrifugal force can be exerted during printing. Even if it is added to the flexo plate, the adhesion sheet for temporary fixing of the flexo plate does not peel off.

Further, after the flexographic plate is temporarily fixed to the carrier sheet, the Y direction central portions of the protruding portions at both ends in the X direction of the adhesion sheet for temporary fixing of the flexographic plate are fixed to the carrier sheet with an adhesive tape of an arbitrary length. After that, by peeling the adhesion sheet for flexo plate temporary fixing from both ends in the Y direction on the plate cylinder and re-adhering it, the sag of the carrier sheet and the flexo plate caused by the difference in the radius of curvature between the flexo plate and the carrier sheet. It is possible to easily remove the slight distortion, the air pool due to the refraction of the foamed resin layer, and the like.

[0044]

【Example】

(Example 1) A foamed resin layer 1 having a thickness of 300 μm on one side with a polyester film having a thickness of 75 μm as a support 10
1 was formed in the following manner. First, 100 parts by weight of urethane resin emulsion (DIC FORM F-520 manufactured by Dainippon Ink and Chemicals, Inc., solid content 50% by weight) and acrylic resin emulsion (Boncoat 3750, manufactured by Dainippon Ink and Chemicals, Inc., solid content 23) 1% by weight) in a mixed emulsion with 0.5 part by weight of polyamine (trade name PA-20, manufactured by Dainippon Ink and Chemicals, Inc., solid content: 0.6% by weight) as a chain extender and stearin as a foaming agent. 10 parts by weight of 30% ammonium acid aqueous solution, 0.5 parts by weight of dimethyl silicone oil as a foam stabilizer, and bisphenol A diglycidyl ether type epoxy resin as a cross-linking agent (trade name CR-5 manufactured by Dainippon Ink and Chemicals, Inc.
L) A compounded emulsion was prepared by adding 2 parts by weight.
Then, the compounded emulsion was treated with a foaming machine to prepare a compounded emulsion: air = 1: 2 foamed emulsion in a volume ratio. Then, the foamed emulsion is applied to the support 10
Was coated on one side with a comma coater, dried with hot air at 100 ° C. for 2 minutes, and further dried with hot air at 150 ° C. for 3 minutes to form a foamed resin layer 11. When observing the foamed resin layer 11 with a microscope, as shown in FIG. 20, there are a large number of bubbles inside, some of the bubbles exist independently, and the rest of the bubbles are continuous with other bubbles in the vicinity in a fine conduit. It was also confirmed that the bubbles close to the surface are continuous with the surface space through the fine conduits and that the fine conduits leading to the surface are evenly distributed.

A polyethylene film having a thickness of 60 μm was laminated as a protective layer 12 on the foamed resin layer 11.

A commercially available rubber-based pressure-sensitive adhesive was applied to the other surface of the support 10 to a thickness of 50 μm to obtain a pressure-sensitive adhesive layer 13. The pressure-sensitive adhesive layer 13 had an adhesion of 1800 g / 20 mm to the stainless steel plate by the 180 ° peeling method.

A release paper having a thickness of 110 μm was laminated as a release layer 14 on the pressure-sensitive adhesive layer 13 to produce a flexographic plate temporary fixing contact sheet 1A as shown in FIG.

Then, as shown in FIG. 13, the adhesion sheet 1A for flexographic plate temporary fixing is cut into a size having a protruding portion 40 of about 25 mm from both end edges of the flexographic plate 2 in the Y direction, and the release layer 14 is peeled off. After that, it was gradually applied while pressing it gently so as not to wrinkle, and then applied to the back surface of the flexo plate 2. 5 to 15 diameters at several places at that time
Although an air pocket of mm was generated, a pin was pierced from the protective layer side, air was squeezed out from the pin hole, and all the air pocket was removed.

Then, as shown in FIGS. 14 and 15,
After the protective layer 12 was peeled off, the flexographic plate 2 was positioned and the flexographic plate temporary fixing adhesive sheet 1A was adhered to the plate cylinder 3. At that time, no air pocket was formed. In order to correct the position of the flexo plate 2, when the flexo plate 2 was peeled off from the plate cylinder together with the flexo plate temporary adhesion sheet 1A, it could be easily peeled off, and the foamed resin layer 1 was formed on the plate cylinder surface.
No remnant of 1 remained. Such adhesion and peeling operations were repeated 10 times and the change in adhesion performance was examined, and no change occurred. Further, the adhesion and peeling operations were performed on the carrier sheet and the sleeve, and the change in the adhesion performance was examined, but no change occurred.

Further, in order to securely fix the flexographic plate 2 to the plate cylinder 3, the protruding portion 40 of the adhesion sheet 1A for flexo plate temporary fixing is fixed to the plate cylinder 3 with an adhesive tape 41, and printing is performed. No positional displacement of the pattern due to the displacement of the plate or stretching was observed, and a printed product with good finishing accuracy was obtained.

Example 2 A laminated body formed in the same manner as in Example 1 had a pin diameter of 1.4 mm, a sharply pointed tapered portion length of 8.5 mm, and a theoretical tip angle of 4.7 °. Protect the needle-shaped pins from the release layer side 14 at the 3 mm pitch, and the tip of the pin is the protective layer
A hole 21 was formed by piercing to the extent that it reached 2, and a contact sheet 1C for flexographic plate temporary fixing as shown in FIG. 3 was manufactured. At that time, the pin hole diameter on the release paper was 0.1 mm, and no pin hole could be visually confirmed on the foamed resin surface.

Then, in the same manner as in Example 1, the flexographic plate temporary fixing adhesive sheet 1C was attached to the back surface of the flexographic plate 2. At that time, air pools having a diameter of 5 to 10 mm were formed at several places, but if the air was gently pressed so as to be squeezed out, all the air pools could be removed. Then, in order to prevent the adhesive in the protruding portion 40 from sticking to a hand or the like during the sticking work, a commercially available dry copy paper was stuck to the adhesive layer 13 in the protruding portion to invalidate the adhesive force.

Then, the protective layer 12 was peeled off, and cotton dust taken out from a household electric vacuum cleaner was attached to the foamed resin to contaminate the surface. In that state, there was almost no adhesion to the plate cylinder. Therefore, the deposits on the surface of the foamed resin were thoroughly washed off with tap water, allowed to air-dry indoors for 24 hours, and then the adhesion and removability to the plate cylinder were examined. Was confirmed.

Next, in order to securely fix the flexographic plate to the plate cylinder, the protruding portion 40 of the adhesion sheet 1C for flexo plate temporary fixing is fixed to the plate cylinder 3 with the adhesive tape 41, and printing is performed. No positional displacement of the pattern due to the displacement of the plate or stretching was observed, and a printed product with good finishing accuracy was obtained.

(Example 3) A releasable type foam sheet (trade name: Papiral B manufactured by Dainippon Ink and Chemicals, Inc.) in which a polyethylene terephthalate (PET) film having a thickness of 75 μm, a urethane resin foam layer having a thickness of 300 μm, and a protective film are laminated. -002LC) PET film surface,
The rubber-based pressure-sensitive adhesive used in Example 1, wherein the pressure-sensitive adhesive coated convex portion 30 has a thickness of 50 μm and a width of 10 mm, and the non-coated concave portion 31 has a width of 1 mm and has a striped pressure-sensitive adhesive layer 1
5 was pattern-coated through a mask. Adhesive layer 15
Was 1400 g / 20 mm in terms of the adhesive force to the stainless steel plate by the 180 ° peeling method. Also, the adhesive layer 1
A release paper having a thickness of 110 μm was laminated as a release layer 14 on 5 to produce a flexographic plate temporary fixing contact sheet 1G as shown in FIG.

Next, as shown in FIG. 16, the flexographic plate temporary fixing contact sheet 1G is provided with a projecting portion 50 of about 25 mm from both end edges of the flexographic plate 2 in the Y direction and a projecting portion 51 of about 15 mm from both end edges in the X direction. Cut into a size with
After peeling off the peeling layer 14, it was attached to the back surface of the flexographic plate 2. At that time, no air pocket was formed.

Then, as shown in FIG. 17, the protective layer 12
After peeling off, the flexographic plate 2 was aligned and brought into close contact with the carrier sheet 4 placed on a flat table. In order to correct the position of the flexo plate 2, the flexo plate 2 is attached together with the flexo plate temporary adhesion sheet 1G to the carrier sheet 4
When peeled off, it was easily peeled off and no residue of the foamed resin layer 11 remained on the carrier sheet surface. Then, in order to securely fix the flexographic plate to the carrier sheet, the Y-direction central portions 52 of the protruding portions at both ends in the X direction of the adhesion sheet for temporary fixing of the flexographic plate are attached to the carrier sheet with an adhesive tape 53 having a length of about 50 mm. It was fixed at 4.

Then, as shown in FIGS. 18 and 19,
While the carrier sheet 4 is hung on the clamp 54 of the plate cylinder, the flexographic plate temporary fixing adhesive sheet 1G is peeled from both ends in the Y direction and re-adhered, and the flexographic plate 2 and the carrier sheet 4 have different radii of curvature. The foamed resin layer 11
The air pool due to the refraction of was removed. Next, the protruding portions 50 at both ends in the Y direction were fixed to the carrier sheet 4 with the adhesive tape 53. Further, the clamp 54 of the plate cylinder was tightened to attach the carrier sheet 4 to the plate cylinder 3. On the adhesion surface between the adhesion sheet for flexo plate temporary fixing and the carrier sheet,
No slack in the carrier sheet, no air pool due to refraction of the foamed resin layer, and no damage to the foamed resin layer were observed, and a uniform thickness was obtained.

[0059]

EFFECTS OF THE INVENTION When the adhesion sheet for temporary fixing of flexographic printing plate according to the present invention is used, the flexographic printing plate can be attached to the printing drum, carrier sheet or sleeve without causing air pockets, so that the flat printing plate has a uniform planar thickness during printing. Is obtained.
Further, since the foamed resin layer has an appropriate cushioning property,
The printing pressure is equalized, it is possible to prevent the occurrence of printing defects such as uneven printing, blurring, and blurring, and it is possible to perform flexographic printing with high finishing accuracy.

When the flexographic plate is attached to the plate cylinder or sleeve, the elasticity of the foamed resin layer absorbs the difference in arc length caused by the difference in radius of curvature between the flexo plate and the plate cylinder or sleeve, and the foamed resin layer It can be pasted without bending. Also, when the carrier sheet with the flexographic plate temporarily fixed on the plane is hung on the plate cylinder, the slack of the carrier sheet caused by the difference in the radius of curvature between the flexographic plate and the carrier sheet, the slight distortion of the flexographic plate, and the foaming The air pocket due to the refraction of the resin layer can be easily removed by re-adhesion work on the plate cylinder.

Further, since the flexographic plate can be easily peeled off when the flexographic plate is reattached or replaced, the flexographic plate, the flexographic plate temporary fixing adhesive sheet and the carrier sheet are not distorted or damaged. Moreover, since the residue of the foamed resin layer does not adhere to the plate cylinder, the carrier sheet or the sleeve and the surface of the foamed resin does not become rough, it is possible to easily and quickly correct the position by reattaching the flexographic plate. be able to.

Further, when the flexographic plate is temporarily fixed with the adhesion sheet for temporary fixing of the flexographic plate and then the protruding portion is fixed with the adhesive tape, the flexographic plate is not peeled off during printing.
Further, when the fixed flexographic plate is peeled off, it can be easily peeled off only by peeling off the adhesive tape on the protruding portion.

Further, since the surface of the foamed resin of the adhesion sheet for flexographic plate temporary fixing retains adhesion and removability as long as it is not contaminated with dust, the flexographic plate is adhered to the flexographic printing plate for temporary fixing after printing. It may be peeled off together with the sheet and stored with the protective layer laminated. The surface of the foamed resin is maintained in a good state, and the protective layer can be peeled off at the time of the next printing, and the work can be performed as it is. Further, even if the surface of the foamed resin is contaminated with dust or the like, it is possible to recover the adhesion force any number of times by washing with water.

Further, even if an oil film or a water film, which generally inhibits adhesion or adhesion, is attached to the surface of the plate cylinder, carrier sheet or sleeve, it does not affect the sucker effect of the foamed resin layer, resulting in good adhesion. And removability can be obtained. That is, when the flexographic printing plate is attached, only the portion where the protruding portion of the adhesion sheet for temporarily fixing the flexographic printing plate is fixed with the adhesive tape needs to be cleaned, so that the plate cylinder, the carrier sheet or the sleeve can be easily managed.

[Brief description of drawings]

FIG. 1 is an enlarged cross-sectional view of one flexographic plate temporary adhesion sheet.

FIG. 2 is an enlarged cross-sectional view of a flexographic plate temporary fixing contact sheet having a perforated structure.

FIG. 3 is an enlarged cross-sectional view of a flexographic plate temporary fixing contact sheet having another punching structure.

FIG. 4 is an enlarged cross-sectional view of a flexographic plate temporary fixing contact sheet having another punching structure.

FIG. 5 is an enlarged cross-sectional view of a flexographic plate temporary fixing contact sheet having another punching structure.

FIG. 6 is a plan view showing a perforation position of one of the pressure-sensitive adhesive layers of the flexo plate temporary adhesion sheet.

FIG. 7 is a plan view showing another punching position of the pressure-sensitive adhesive layer of the adhesion sheet for flexographic plate temporary fixing.

FIG. 8 is an enlarged cross-sectional view of a flexographic plate temporary fixing contact sheet having an uneven pressure-sensitive adhesive layer.

FIG. 9 is an enlarged cross-sectional view of a flexographic plate temporary fixing contact sheet having another pressure-sensitive adhesive layer having an uneven structure.

FIG. 10 is a plan view showing one uneven structure of the pressure-sensitive adhesive layer of the adhesion sheet for flexographic plate temporary fixing.

FIG. 11 is a plan view showing another uneven structure of the pressure-sensitive adhesive layer of the adhesion sheet for flexographic plate temporary fixing.

FIG. 12 is a plan view showing another uneven structure of the pressure-sensitive adhesive layer of the adhesion sheet for flexographic plate temporary fixing.

FIG. 13 is a plan view showing a state in which a flexo plate temporary adhesion sheet is attached to a flexo plate.

FIG. 14 is a front view showing a state in which the flexographic plate of FIG. 13 is stuck on a plate cylinder.

15 is an enlarged cross-sectional view taken along line MM of FIG.

FIG. 16 is a plan view showing another state in which the adhesion sheet for temporarily fixing the flexographic plate is attached to the flexographic plate.

FIG. 17 is a plan view showing a state in which the flexographic plate of FIG. 16 is temporarily fixed to a carrier sheet.

FIG. 18 is a front view showing a state where the carrier sheet of FIG. 17 is mounted on the plate cylinder.

19 is an enlarged cross-sectional view taken along the line NN of FIG.

FIG. 20 is an enlarged sectional view of a foamed resin layer of a contact sheet for flexo plate temporary fixing.

FIG. 21 is an enlarged sectional view of a conventional fixing sheet of a printing plate.

FIG. 22 is an enlarged sectional view of a conventional double-sided pressure-sensitive adhesive tape for fixing a flexographic plate.

FIG. 23 is an enlarged cross-sectional view of a conventional printing plate fixing adhesive tape.

[Explanation of symbols]

1, 1A, 1B, 1C, 1D, 1E, 1F, 1G Flexographic printing plate temporary fixing contact sheet 2 Flexographic printing plate 3 Plate cylinder 4 Carrier sheet 10, 101, 111 Support 11 Foamed resin layer 12 Protective layer 13, 15, 102 , 104, 123 Adhesive layer 14 Release layer 20, 21, 22, 114 Hole 30 Convex part 31 Recessed part 40, 50, 51 Overhanging part 41, 53 Adhesive tape 52 Central part 54 Clamp 100 Fixing sheet 103, 105 Exhaust path 110 Flexo Double-sided adhesive tape for plate fixing 112 First adhesive layer 113 Second adhesive layer 120 Adhesive tape for plate fixing 121 Foam substrate 122 Plastic film

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location C09J 7/02 JJG JLE

Claims (3)

[Claims] 1. A support (10) made of a plastic film (10) (B) A large number of air bubbles provided inside one side of the support, and these air bubbles are adjacent to other air bubbles and / or surfaces. Foamed resin layer (11) (C) Protective layer on foamed resin layer (12) (D) Adhesive layer (13) provided on the other surface of the support, and (E) ) A contact sheet for flexographic plate temporary fixing, which is a laminate comprising a release layer (14) on an adhesive layer. 2. The laminate according to claim 1, wherein a large number of holes (20, 21, 22) for venting the adhesive layer (13) to the foamed resin layer (11) are provided. Adhesive sheet for temporary fixing of flexo plate. 3. The laminate according to claim 1, wherein the pressure-sensitive adhesive layer (13) includes a convex portion (30) coated with a pressure-sensitive adhesive.
A contact sheet for flexographic plate temporary fixing, comprising a pressure-sensitive adhesive layer (15) comprising a concave portion (31) which is applied thinner than the convex portion or is not applied at all.