JPH0411821Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field This invention relates to a compressible offset blanket. More particularly, the present invention relates to a compressible offset blanket for printing, which includes a compressible layer between a surface layer and a reinforcing layer.

<Background and Prior Art> Conventionally, the above-mentioned compressible offset blanket has been designed to provide compression between the surface layer 1 and the reinforcing layer 2, as shown in FIG. The construction of gender 3 is being carried out.

This compressible layer 3 may be made of, for example, a cellular material made of non-woven fabric impregnated with latex (see Japanese Patent Publication No. 37-13110), or made of a rubber sponge manufactured using a foaming agent ( (see German Patent No. 1165046) have been proposed.

However, the former case has not been put to practical use because it cannot exhibit the desired printing characteristics. In the latter case, it is actually difficult to form bubbles a of a uniform diameter within the compressible layer 3, which has an extremely thin thickness of about 0.2 to 1 mm, and it is difficult to generate uniform printing pressure over the entire surface of the bracket. However, further improvement is desired.

For this reason, a compressible layer 3 has been developed in which the compressible layer 3 is made of a rubber elastic material mixed with micro hollow spheres of soluble or crushable material such as thermoplastic plastic (see Japanese Patent Publication No. 7371/1983). There is a problem that the manufacturing process becomes complicated.

<Purpose> The purpose of this invention is to provide a compressible offset blanket that can solve the above-mentioned problems using a principle completely different from that of the above-mentioned known technology.

<Structure> The structure of this invention to achieve the above object is that in a compressible offset blanket in which a compressible layer is formed between a surface layer and at least one reinforcing layer, the compressible layer is It is characterized in that it is constituted by an elastic sheet made of a rubber sheet having a satin-like uneven pattern.

<Example> Next, Figures 1 to 3 show examples of this invention.
This will be explained below with reference to the figures.

A shows the entire compressible offset blanket, one of which is the surface layer. This surface layer 1 has a double structure consisting of an oil-resistant rubber layer 10 and a fiber layer 11 laminated on the back surface thereof. 2 is a reinforcing layer, and in the case shown, an intermediate rubber layer 2 is provided between the rubberized fiber backing layers 20 and 20'.
1 is interposed.

Reference numeral 3 denotes a compressible layer characterized by this invention, which is constructed between the surface layer 1 and the reinforcing layer 2, and includes an elastic sheet 3 having a satin-like uneven pattern a on one side and both sides.
Consists of 0. As this elastic sheet 30, a rubber sheet with a total thickness of about 0.1 to 1 mm and a pitch P of forming convex portions a' of 10 to 100 μm is used.
The uneven pattern a is formed using a mold or a molded roll in which a fine uneven pattern is engraved by shot blasting, etching, or the like. And the elastic sheet 30 constituting the compressible layer 3
is laminated between the upper fiber layer 11 and the lower fiber backing layer 20 via primer layers (adhesive layers) b, b.

As a result of testing Blanket A with such a configuration installed in a printing machine, it was found that the contours of each of the countless dots (halftone dots) that make up a masterpiece line were very sharp, and the diameter of the halftone dots was larger than the specified diameter. There is no so-called "thickening phenomenon" where halftone dots become thicker, there is no so-called "skipping phenomenon" where spots appear in each halftone dot, and there are no "shocks" that appear on the printing screen due to the clearance between the gears of the printing roller. It was confirmed that an extremely good printed image could be obtained, with no striped shading called "eyes" occurring.

Note that the surface layer 1 may have a single layer structure consisting only of the oil-resistant rubber layer 10 without forming the fiber layer 11, and the reinforcing layer 2 may also include at least one layer of the fiber backing layer 20. That's fine.

<Effects> According to the compressible offset blanket of this invention constructed as described above, the compressible layer is composed of an elastic sheet having a satin-like uneven pattern. It can exhibit elasticity, have sharp halftone dots, and produce very good printed images without thickening, voids, or shadows.

Furthermore, it is possible to provide a material that exhibits various excellent practical effects, such as the ability to form the compressible layer itself easily and at low cost.

[Brief explanation of the drawing]

FIG. 1 is a sectional view, FIG. 2 is a perspective view of an elastic sheet, and FIG. 3 is a sectional view showing an example of a conventional product. DESCRIPTION OF SYMBOLS 1...Surface layer, 10...Oil-resistant rubber layer, 11...
...Fiber layer, 2...Reinforcement layer, 20, 20'...Fibre backing layer, 3...Compressible layer, 30...Elastic sheet, A...Compressible offset blanket, a...
...Nashiji-like uneven pattern.

Claims (1)

[Claims for Utility Model Registration] 1. A compressed offset blanket comprising a compressible layer between a surface layer and at least one reinforcing layer, wherein the compressible layer is made of rubber having a satin-like uneven pattern. A compressible offset blanket comprising an elastic sheet. 2. Claim 1 of the above utility model registration, in which a satin-like uneven pattern is formed on both sides of the elastic sheet.
Compressible offset blanket as described in Section 1. 3. Claim 1 of the above utility model registration, in which a satin-like uneven pattern is formed on one side of the elastic sheet.
Compressible offset blanket as described in Section 1. 4. The compressible offset blanket according to claim 1, wherein the surface layer has a single layer structure of an oil-resistant rubber layer. 5. Claim 1 of the above utility model registration in which the surface layer has a double structure consisting of an oil-resistant rubber layer and a fiber layer.
Compressible offset blankets as described in Section.