Gravure printing roll and method for manufacture thereof

Abstract

Disclosed is a novel gravure printing roll which has no toxicity, causes no deterioration of the environment, has a surface-reinforcing coating layer and is excellent in print durability and printing performance. Also disclosed is a method for manufacture of the gravure printing roll. The gravure printing roll comprises a hollow roll, a copper-plated layer which is provided on the surface of the hollow roll and has multiple gravure cells formed on its surface, and a diamond-like carbon coating film which coats the surface of the copper-plated layer, wherein each of the gravure cells coated with the diamond-like carbon coating film has a depth of 5 [mu]m or greater and less than 10 [mu]m.

Description

technical field [0001] The present invention relates to a gravure plate-making roller capable of preparing a surface-strengthening coating with sufficient strength without chrome plating and having grooves of extremely shallow depth, and a manufacturing method thereof, in particular to a surface-strengthening coating used as a substitute for a chromium layer. A gravure plate-making roll having a diamond-like carbon (DLC) layer and simultaneously achieving sufficient printing density (optical density, transmittance density) and concealment in gravure printing, and a method for manufacturing the same. Background technique [0002] In the existing gravure plate-making rollers, a plate with 175 screen lines per inch and a groove depth of 25 μm to 30 μm in the darkest part is generally used, and inorganic pigments containing more than 90% of particle diameters of 2 or 3 μm are used Gravure printing with gravure ink of organic pigments. [0003] The basic composition of ink is th...

AI Technical Summary

Problems solved by technology

[0005] Chemical substances used in oil-based inks such as toluene MEK (1) strong pungent smell

(2) Low flash point and high volatility, so it is easy to catch fire and explode when fully charged

(3) Dangerous to health if inhaled

(4) have an impact on the environment

(5) Unfavorable for reduction of carbon dioxide emission

[0006] Organic compounds (VOC) (1) such as solvents evaporated in the printing process are discharged outside the factory, causing air pollution and odor problems around the factory

(2) If the factory is not fully drained, there is a risk of fire and explosion, and it is dangerous to the working environment such as endangering the health of the workers.

(3) The solvent that has not evaporated remains on the film and becomes the cause of the unique smell of the printed bag

However, the current situation is that in the chromium plating process, highly toxic hexavalent chromium is used, so in addition to increasing unnecessary costs to maintain work safety, there is also a problem of pollution. A surface strengthening coating that replaces the chromium layer is expected the emergence of

[0012] On the other hand, in the manufacture of gravure rolls (gravure cylinders), techniques are known in which diamond-like carbon (DLC) is used as a surface-strengthening coating on a copper-plated layer in which grooves are formed (Patent Documents 1 to 3) and The technology of forming a groove to form a printing plate after forming a DLC layer on a copper-plated layer (Patent Document 4), however, the DLC layer has a problem of being easily peeled off due to weak adhesion between the DLC layer and copper

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