JPS6114997A - Inking roller for offset printing - Google Patents

Abstract

PURPOSE:To provide the titled roller not deteriorated by a solvent and excellent in a printing ink receiving and releasing property, constituted by forming at least the surface of a roller main body of an inking roller for offset printing from an urethane resin having a metal powder such as an Al-powder uniformly mixed therein. CONSTITUTION:The center part 11 of a roller main body 7a is formed of a synthetic rubber layer and a surface layer 12 is formed of a composition prepared by uniformly mixing a metal powder such as an Al-powder or a brass powder, for example, with an one-component liquid ester type urethane resin to obtain an objective roller.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field 1] The present invention relates to an inking roller for offset printing.

1 Background Art 1 FIG. 1 shows the schematic configuration of an offset printing press. Normally, an offset printing machine consists of an offset cylinder 1, an impression cylinder 2, a plate cylinder 3, and a PS plate 4 attached to a plate g43. A water supply roller 6 that supplies water to the image, an inking roller 7 that supplies printing ink to the PS board 4, and a printing medium 8.
It consists of an a-ra 9 that conveys. In the figure, 10 is a blanket for offset printing. By the way, since the material of the roller body of the inking roller 7 of the conventional offset printing press is butyl rubber or nitrile rubber, there are the following problems.

In other words, commonly used printing inks contain pigments, resins, and solvents such as flax oil, solvent oil, and class 1 light oil.
Of these, Class 1 light oil had a significant effect on the inking roller 7. In other words, class 1 light oil degrades the butyl rubber or nitrile rubber used in the roller body, forming large irregularities on its surface, and the printing ink supplied from the ink tank to the roller body adheres to the irregularities, making it susceptible to damage. There was a drawback that printing ink could not be efficiently supplied to the PS board 4 due to poor performance. Another disadvantage is that the amount of printing ink supplied from the ink tank to the roller body must be increased.

[Objective of the Invention 1] The present invention has been made in view of the above-mentioned drawbacks, and its purpose is to provide an inking roller for offset printing that does not deteriorate due to solvents and has excellent resistance to printing ink. It is on offer.

[Disclosure of the Invention 1 and 1 Figure 2 shows a cross section of this embodiment, and the roller body 7a is formed of a general synthetic rubber layer 11 in the center, and a one-component ester-based layer 11 is formed on the surface of the roller body 7a. The surface layer 12 is formed of urethane resin (Kansai Paint Co., Ltd., product number R-2). This ester-based urethane resin was uniformly mixed with aluminum powder (250#) at a volume ratio of 2.5% to the resin.

However, when an offset printing machine as shown in FIG. 1 using this embodiment was used, the following results were obtained. In other words, the printing ink used (manufactured by Dainippon Ink & Chemicals Co., Ltd., product number SA) was supplied from an ink tank (not shown) to the roller body 7a, and when 1 million sheets were printed, the first type of solvent contained in the printing ink was No deterioration due to light oil was observed, and there was no penetration into the center. In addition, since no unevenness due to deterioration occurs and the aluminum particles appear on the surface of the surface layer 12, the ink transfer to the PS plate 4 attached to the plate cylinder 3 is good, and the result is excellent resistance. Ta. Furthermore, the minute irregularities created by the aluminum particles prevented ink particles from scattering.

Dog mζ This example is the aluminum grain F in Example 1 above.
The size of the ink was changed to 350#, and in this example, the dislocation of the single layer ink was better than in Example 1.

In this example, the capacity ratio to the resin in Example 1 was set to 2.
The amount was increased from 5% to 10%, and in this example as well as in Example 2, the single layer ink dislocation was better than in Example 1.

and 11 (In this example, as in Example 1, the roller main body 7a is formed with a general synthetic rubber layer 11 in the center, and the surface is coated with a two-component ester-based urethane resin (Kansai Paint Co., Ltd. Table 1r112 is formed using product number R-1).This ester-based urethane resin contains 5.5% of the resin.
Aluminum powder (300#) was evenly mixed in at a volume ratio of .

However, even in this example, the same results as in Example 1 were obtained during use. Note that a two-component type ester urethane resin can be used for the water supply roller because it has high water film permeability.

Although the metal powder used in each of the above Examples is aluminum, brass may also be used, and in this case, the particle size was similar to that of aluminum, and the same effect was obtained with a light weight. In this case, the color of the roller body 7a is silver in the case of aluminum, but it is gold in the case of brass.

Further, in each embodiment, the hardness of the surface layer 12 is appropriately obtained, so that it is suitable for measuring the ink film pressure, and the amount of ink supplied from the ink tank can be controlled to be minimized by measuring the ink film pressure.

[Effects of the Invention 1] The present invention provides an inking roller for offset printing that supplies printing ink to the plate cylinder as described above, in which at least the surface layer of the roller body is made of urethane-based ink that is almost uniformly mixed with metal powder such as aluminum or brass. Since it is made of resin, the roller body will not deteriorate due to the influence of the solvent contained in the printing ink, and there will be no unevenness due to deterioration, and the surface layer will have an appropriate hardness due to the metal powder. At the same time, minute irregularities are formed on the front lines, so there is no scattering of ink particles, and dislocation is improved, which improves the resistance of the roller body, resulting in the effect that the amount of printing ink used can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of an offset printing press, and FIG. 2 is a sectional view of an inking roller of the present invention, where 7 is an inking roller, 7a is a roller body, and 12 is a surface layer. Agent Patent Attorney Ishi 1) Ai 7 Figure 1 Figure 2

Claims (1)

[Claims] 1) In an inking roller for offset printing that supplies printing ink to a plate cylinder, at least the surface layer of the roller body is made of urethane resin into which metal powder such as aluminum or brass is almost uniformly mixed. An inking roller for offset printing characterized by comprising: 2) The inking roller for offset printing according to claim 1, characterized in that a one-component reaction type ester urethane resin is used as the urethane resin. 3) The inking roller for offset printing according to claim 1, characterized in that a two-component reaction type ester urethane resin is used as the urethane resin. 4) Volume ratio of metal powder to urethane resin is 2.5%
~10% and the size of metal powder is 250#~3
Claim 1 characterized in that it is configured as 50#.
The inking roller for offset printing according to item 1, 2 or 3.