摘要 |
A process for the production of patterns on a substrate bearing a layer of a negative-working, light-sensitive composition comprising at least one 1,4-dihydropyridine compound substituted in the 4 position by a 2'-nitrophenyl ring which becomes tacky and tonable on exposure to actinic radiation, comprising the steps of: (a) exposing said light-sensitive layer imagewise to actinic radiation whereby tacky areas are formed, and, (b) toning said exposed tacky areas with finely divided powders. |