[A study of aggregate behavior of green-sensitive dyes containing fluorine]

Five different-structure carboncyanine dyes containing fluorine in methanol solution and the aggregate behavior on the surface of AgIBr tabulate grains were investigated, the photographic capability determined and the sensitive multiple calculated. From the monomolecular absorption curves of dye1, dye2 and dye3 in methanol solution, it can be seen that when the substitute changed from C2H5 to CH3 to no substitute, the maximal absorption peak shifted to a shorter wavelength. Sensitive dye with ethylene (dyel) adsorbed on the AgBrI surface formed a higher peak of J-aggregate with a higher sensitive multiple. Sensitive dye with no substitute (dye3) did not form J-aggregate, which had a low sensitive multiple and reduced the sensitivity. Compared with dye5, dye4 had a sharper and narrower reflective spectrum and a higher sensitive multiple. The results showed that a different-structure dye adsorbed on silver halide grains formed a different J-aggregate. The sensitive dye of J-aggregate with a sharper absorption spectrum had a higher sensitive multiple.