A process as in claims 11, 12, 13, 14 or 15, wherein said colorant is an electrically photosensitive material selected from the group consisting of(a) aromatic vinyl compounds having a condensed heterocyclic nitrogen-containing nucleus; (b) aromatic vinyl arylamine compounds; (c) aromatic vinyl compounds having a heterocyclic nucleus; (d) merocyanine and benzylidenes having at least one nucleus se