JPH11254656A - Screen printing plate cleaning sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize simple removal and cleaning of an ink which is transferred to the rear side of a screen printing plate, by a method wherein a foam layer is formed on at least one side of a base material. SOLUTION: A screen printing plate cleaning sheet 1 consists of a base material 2 and a foam layer 3 formed on one side of the base material 2. To the surface of this foam layer 3, proper self-adhering properties such as the order of the self-adhering properties, which can be pasted to the screen printing plate and easily peeled off without feeling a large resistance at its peeling off, are given. Accordingly, by peeling off the foam layer 3 side of the sheet pressingly pasted to a printing plate, on which an ink is adhered, the foam layer 3 comes into tight contact with the uneven part of the screen mesh of the printing plate by means of the soft elasticity intrinsic to the foam layer 3 and a fine unevenness developing on the surface of the foam layer 3, resulting in adhering and adsorbing the ink transferred to the rear side of a printing plate and easily removing the ink from the printing plate. Further, since the ink is removed through the adsorbing action of the foam layer 3, no organic solvent is necessary.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning sheet for removing ink and the like behind a screen printing plate.

[0002]

2. Description of the Related Art In screen printing, after a certain number of printings, ink runs behind the screen printing plate and contaminates a printing material, so that accurate and beautiful printing cannot be performed. For this reason, conventionally, the printing plate has been cleaned by wiping the ink behind the screen printing plate with an organic solvent. However, in the method of cleaning a screen printing plate using an organic solvent, if the size of the printing material is large, it takes a long time to clean the printing plate, and the working efficiency is reduced. In addition, the use of an organic solvent causes safety and health and environmental problems.

[0003]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a screen printing plate cleaning sheet which can easily clean a screen printing plate with high working efficiency. Another object of the present invention is to provide a screen printing plate cleaning sheet which does not cause safety, health and environmental problems.

[0004]

Means for Solving the Problems The present inventors have conducted intensive studies to achieve the above object, and as a result, when a sheet having a specific structure is used, the ink behind the screen printing plate is easily removed and cleaned. They found what they could do and completed the invention. That is, the present invention provides (A) a base material,
(B) A screen printing plate cleaning sheet comprising a foam layer formed on at least one surface of the substrate.

[0005]

According to the screen printing plate cleaning sheet of the present invention, the foam layer side is applied to the printing plate to which the ink is adhered while being pressed, and then peeled off to obtain the soft elasticity of the foam layer. And the fine irregularities generated on the surface of the foam layer, the foam layer adheres well to the irregularities of the screen mesh of the printing plate, and adheres and adsorbs the backed ink to easily remove it from the printing plate. Further, since the ink is removed by the adsorption action of the foam layer as described above, an organic solvent is not required.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to the drawings as necessary. FIG. 1 is a schematic sectional view (conceptual diagram) showing an example of the screen printing plate cleaning sheet of the present invention. In this example, the screen printing plate cleaning sheet 1 includes a base material 2 and a foam layer 3 formed on one surface of the base material 2.

The substrate 2 is not particularly limited, and may be a conventional film such as an olefin resin (polyethylene,
Plastic films such as polypropylene, polyester, vinyl-based resin (eg, polyvinyl chloride), and styrene-based resin; nonwoven fabric; cloth; paper; The thickness of the base film 7 is not particularly limited, and can be appropriately set in consideration of strength, workability, and the like.
0 μm, more preferably about 15 to 100 μm.

The resin constituting the foam layer 3 is not particularly limited as long as it is a foamable resin. For example, rubber, acrylic resin, urethane resin, olefin resin, silicone resin, vinyl ether resin, Examples include a styrene resin, a vinyl chloride resin, a phenol resin, a urea resin, and an epoxy resin. Among the above resins,
Resin having adhesiveness, for example, rubber (for example, natural rubber, styrene-butadiene copolymer rubber, polyisobutylene, butyl rubber, recycled rubber, rubber latex, styrene-isoprene-styrene block copolymer, polybutadiene, chloroprene rubber, acrylic rubber And acrylic resins (for example, acrylic resins having a C _2-10 alkyl acrylate as a main constituent monomer and having a Tg of about −20 to −70 ° C .; styrene-acrylate copolymers), urethane Resin, olefin resin (eg, polyethylene; polypropylene; ethylene copolymer such as ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ethylene-acrylate copolymer), and silicone resin Is preferred. The resin may be cross-linked. The resins can be used alone or in combination of two or more.

The expansion ratio of the foam layer 3 varies depending on the type of resin and the foaming method.
It is about 0 times. The foam layer 3 contains various additives, for example, a plasticizer, an antioxidant, a flame retardant, an ultraviolet absorber, a coloring agent, an antistatic agent, a filler, an adhesive, a tackifier, a crosslinking agent, and the like. It may be.

[0010] The thickness of the foam layer 3 may be in a range that does not impair the strength and workability.
Preferably, it is about 0.1 to 2 mm. Note that an undercoat agent layer or the like may be provided between the base material 2 and the foam layer 3. Further, the foam layer 3 may be formed on both surfaces of the base material 2.

The foam layer 3 of the cleaning sheet 1 of the present invention
It is preferable that the surface has a sufficient degree of adhesiveness, for example, such that it can be attached to a screen printing plate and can be easily peeled off without feeling large resistance when peeled off. In a preferred cleaning sheet, the adhesive strength of the cleaning sheet of the present invention is, for example, 1 to 200 gf / 25 mm, particularly 3 to 100 gf / 25 mm, particularly 5 to 80 gf / by a measuring method according to JIS-Z-0237. 25
A cleaning sheet of about mm is included. The adhesive strength can be adjusted by appropriately selecting the type of the resin constituting the foam layer 3 and the type and amount of the additive.

The cleaning sheet of the present invention can be produced by using a conventional foam molding method, for example, an extrusion foam molding method or an injection foam molding method. Alternatively, it can be manufactured by applying a mixed solution containing a resin constituting the foam layer 3 and a suitable foaming agent onto the base material 2 and then subjecting the mixture to heating and foaming. The foaming method can be appropriately selected according to the type of the resin, etc., and is a method of foaming by mechanical stirring (mechanical foaming method), a method using a reaction product gas, a foaming agent (a volatile foaming agent or a decomposable foaming agent). ), A method for removing soluble substances, a method for foaming by spraying, a method for forming a syntactic foam, and a sintering method. The screen printing plate cleaning sheet of the present invention may be in the form of a tape, or may be wound in a roll.

[0013]

EXAMPLES The present invention will be described below in more detail with reference to Examples, but the present invention is not limited to these Examples.

Example 1 A foam layer made of rubber latex having a thickness of 0.8 mm was formed on one surface of a polyester film (substrate) to a thickness of 0.025 mm by a mechanical foaming method. Obtained.

Example 2 A polypropylene film (substrate) having a thickness of 0.04 mm was coated on one side with 100 parts by weight of an acrylic pressure-sensitive adhesive and heat-expandable microcapsules (Matsumoto Microsphere-F-301D manufactured by Matsumoto Yushi Seiyaku Co., Ltd.). A) a mixture with 10 parts by weight, and the microcapsules were expanded by heating to form a 0.15 mm-thick foam layer, and a cleaning sheet was obtained.

Comparative Example 1 Rubber latex was applied to one side of a polyester film (substrate) to a thickness of 0.025 mm to a thickness of 0.05 mm after drying to obtain a cleaning sheet.

Comparative Example 2 An acrylic adhesive was dried on one side of a polypropylene film (substrate) having a thickness of 0.04 mm to a thickness of 0.03 mm after drying.
And a cleaning sheet was obtained.

Experimental Example The adhesive strength of each cleaning sheet obtained in Examples 1 and 2 and Comparative Examples 1 and 2 was measured according to JIS-Z-0237. In addition, an operation was performed in which each cleaning sheet was attached to the back side of the screen printing plate on which the ink had flowed back after being used a certain number of times and peeled off, and the ink removability of each cleaning sheet was evaluated according to the following criteria. ：: Good adhesion to the uneven surface of the screen mesh and good ink removal ×: Poor adhesion to the uneven surface of the screen mesh and poor ink removal The results are shown in Table 1.

[0019]

[Table 1]

According to the sheet for cleaning a screen printing plate of the present invention, the ink or the like that has flowed behind the screen printing plate can be efficiently removed by a simple operation of sticking and peeling. Further, since there is no need to use an organic solvent, there is no problem that the working environment is deteriorated. It is also advantageous in terms of environmental protection.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of a screen printing plate cleaning sheet of the present invention.

[Explanation of symbols]

 1 Screen printing plate cleaning sheet 2 Substrate 3 Foam layer

Claims (2)

[Claims] 1. A screen printing plate cleaning sheet comprising (A) a base material and (B) a foam layer formed on at least one surface of the base material. 2. The screen printing plate cleaning sheet according to claim 1, wherein the foam layer is made of an adhesive resin.