Process for the burning-in of light-sensitive layers during the preparation of printing forms

Claim 1

In a process for the preparation of an offset printing form, comprising exposing and developing a single, positive-working light-sensitive layer provided on a support, said layer containing a diazo compound as a light-sensitive ingredient of the light-sensitive layer to be processed, the improvement consisting essentially of burning-in said layer to be processed by heating the printing form to at least 180° C. by exposure to electromagnetic radiation which contains an infrared fraction of 50 to 87 percent, a fraction in the visible region of 10 to 30 percent, and an ultraviolet fraction of 3 to 30 percent, for a period of time between about 15 to 90 seconds which will not adversely affect the mechanical properties of said support to a significant extent, wherein the printing form is irradiated by said electromagnetic radiation from the side of said exposed and developed layer.