Method and device for producing colour images by way of a UV laser on pigmented substrates, and products produced as a result

摘要

A method is described for producing a character, pattern, symbol and/or image (8) on a substrate (2) by way of pigment particles (1) which are arranged thereon and lose their color effect under the action of a laser (23), wherein different pigment particles (1) with at least three different color effects are arranged on and/or in the substrate (2). The invention is distinguished by the following method steps: (a) production of a color chart (14), in which the individual color effect of individual pigment particles (1) or individual clusters of pigment particles is contained as a function of their spatial coordinate on and/or in the substrate (2); (b) spatially resolved irradiation, which changes the color effect of only individual pigment particles (1) or individual clusters of pigment particles, by way of a laser (23) at a single frequency on the basis of the color chart (14) in order to produce a resulting color effect. Furthermore, the present invention relates to substrates, in particular security documents, produced using a method of this type, and devices for carrying out methods of this type.

主权项

1. A method for producing a multi-coloured character, pattern, symbol or image on a substrate having pigment particles which are arranged thereon, wherein the pigment particles lose or change their colour effect under the action of a laser, wherein different pigment particles having at least two different colour effects are arranged on or in the substrate, wherein the pigment particles are distributed substantially randomly as a function of the location coordinates, wherein the method comprises the following method steps:
a producing a colour map, in which the individual colour effect of individual pigment particles or individual clusters of pigment particles is contained as a function of the location coordinates thereof on or in the substrate; b spatially resolved irradiating of the substrate with a laser at a single frequency adapted to only change the colour effect of individual pigment particles or individual clusters of pigment particles in their colour effect on the basis of the colour map to produce a resulting colour effect.