US Patent 7114438 Printing machine including central impression cylinder

Printing machine having at least one impression cylinder (16), characterised in that the impression cylinder (16) has a cylinder body (44) made of a material which, in circumferential direction of the impression cylinder (16) has a linear thermal expansion coefficient of less than 2×10−6 K−1. The material may be a composite material, for example, a material containing carbon fibers, in particular a synthetic resin reinforced with carbon fibers.