| 摘要 |
PURPOSE:To enhance sensitivity and to eliminate occurrence of fog by incorporating a specified N- and O-contg. heterocyclic sensitizing dye and a specified N- and O-contg. heterocyclic sensitizing dye in a silver halide emulsion. CONSTITUTION:The silver halide emulsion high in sensitivity spectrally sensitizable without occurrence of fog can be obtained by incorporating a combination of sensitizing dyes represented by formula I and II in which R1, R2, R3, and R4 are each H, alkyl, or aryl, and each of R1 and R2, R3 and R4 may form a 5- or 6-membered aromatic ring; each of R5, R6 is substituted to a quaternary ammonium N; each of R5 and R2, R6 and R4, R5 and R7, and R9 may form a hetero ring; each of R7, R9 is H, alkyl, aryl, cyano, or the like; each of R7 and R9 may form a 5- or 6-membered ring; R8 is H, alkyl, aryl, heterocyclic, cyano, or the like; Y<-> is an anion; and p is O or a positive integer. |
