A method for producing coloured patterns or images including the steps of(1) forming a polymer layer containing a soluble phthatocyanine precursor, selected from the group consisting of compounds of formulae (I) to (VII), ##STR14## wherein L1 and L2 are independently from each other C1 -C18 alkoxy, C1 -C18 alkylthio C1 -C18 alkylamino, C2 -C18 dialkylamino, or an unsubstituted or with 1 or 2 C1 -C