Premium
A study of oil‐soluble azo dyes for silver dye‐bleach photography
Author(s) -
Peng Xiaojun,
Yang Jinzong
Publication year - 1995
Publication title -
journal of the society of dyers and colourists
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.297
H-Index - 49
eISSN - 1478-4408
pISSN - 0037-9859
DOI - 10.1111/j.1478-4408.1995.tb01722.x
Subject(s) - chemistry , substituent , bleach , alkyl , solubility , phosphate , organic chemistry , tributyl phosphate , nuclear chemistry , extraction (chemistry)
Azo dyes used in silver dye‐bleach photography have been studied, emphasising the relationships between molecular structures on the one hand and their oil solubility and bleachability on the other. A moderately bulky substituent at the ortho ‐position to the azo group is more favourable to good solubility than is a long‐chain alkyl substituent at another location. A dye containing the long‐chain alkyl group confers good colour density in aliphatic oils, such as tributyl phosphate (TBP) and dibutyl phthalate (DBP), but poor density in aromatic oil, such as tricresyl phosphate (TCP). The presence of the electron‐withdrawing substituents is likely to render the azo group more bleachable. Oils also play a role in the rate of bleach of the dyes: bleaching in TBP and DBP is superior to that in TCP