METHINE DYES FOR PHOTOGRAPHIC ANTIHALATION AND FILTER LAYERS

摘要

1320168 N-substituted pyridinium salts EASTMAN KODAK CO 11 June 1970 [12 June 1969 5 Nov 1969] 28369/70 Heading C2C [Also in Divisions C4 and G2] 2 - Methyl - 4,6 - di - p - tolylpyrylium perchlorate is prepared by reacting acetic anhydride and 4SP1/SP-methylacetophenone and then adding NaClO 4 , and is converted to 1-dimethylamino-2- methyl-4,6-di-(p-tolyl) pyridinium perchlorate by 1,1-dimethylhydrazine. Corresponding pyridinium salts containing 1-anilino, 1-(p-methyl)- anilino or 1 - (4H - 1,2,4 - triazol - 4 - yl) or 4,6- di-[p-(chloro or methoxy)phenyl] substituents, and/or iodide or tetrafluoroborate anions are prepared similarly.