Roller for fluid film preparation or application

Abstract

The invention relates to a roller for fluid film preparation, having an inside core (3), a first layer A, which surrounds the core and has a first hardness, and a second layer B, which surrounds first layer A and has a second hardness different from that of the first layer, where the two surround the core with a layer thickness d. In order to design a roller for fluid film preparation, particularly for offset printing, with which inhomogeneities in the printing medium or printed product, particularly ribbing on the printed product, can be at least largely avoided, and which is cost-efficient to manufacture, it is proposed that the roller coating be provided, at least in certain sections, with an essentially continuous hardness gradient through the layer thickness (dV). In order to produce the hardness gradient, a gradient of a hardness-modifying substance or agent, or a precursor thereof, e.g. an agent that increases the degree of cross-linking, can be incorporated into the coating material by means of diffusion or migration of the substance or agent from at least one surface of the roller coating.

Dependencies are inferred from the claim text.