Patent ID: 6487386
Filing Date: 2002-11-26
Classification: G03G

Abstract:
A device for applying decorations and characters on glass, glass ceramic or ceramic products by means of an electrophotographic method, said device comprising:an image roller (5) provided with an electrostatically chargeable photoconductive layer; a photo-exposure assembly (6) for generating an electrostatic charge image corresponding to at least one of decorations and characters to be applied; a supply container (8) for a toner and means (8a) for developing the electrostatic charge image with said toner to form a toner image; an intermediate substrate comprising a dimensionally stable transfer roller (7) for receiving the toner image, said transfer roller being in direct contact with said image roller on one side thereof and in direct contact with a glass, glass ceramic or ceramic product (2) on the other side thereof; at least three coronas including a first corona (9a1, 9a2), a second corona (10a) and a third corona (9b1, 10b), said first corona (9a1, 9a2) being arranged on said transfer roller (7), said second corona (10a) being arranged beneath said product and in the vicinity of a zone of contact of said transfer roller (7) with said product, said at least three coronas comprising means for electrostatically transferring the toner image onto said product (2); heating means for burning the toner image onto the product, after electrostatically transferring the toner image onto the product; and a counterpart roller (11) embodied as a hollow roller and arranged beneath the product (2) in direct contact with said product (2) in the zone of contact of the product (2) with the transfer roller (7); wherein said second corona (10a) is arranged in an interior of the counterpart roller (11) and on a surface thereof in the vicinity of said zone of contact and said first corona (9a1, 9a2) on said transfer roller (7) is arranged in a region of contact of the transfer roller (7) with the image roller (5) and has an electrical potential that is opposite in sign to a charge of the toner image on the image roller (5); and wherein said third corona (9b1, 10b) has an electrical potential of opposite sign from that of the first corona (9a1, 9a2) and the second corona (10a) and Is arranged on the transfer roller (7) in the vicinity of the zone of contact of the transfer roller (7) with the product (2).