Photographic products and processes
AssigneePolaroid Corporation
InventorsCharles E. Jandrue, Sr., Marcis M. Kampe, Myron S. Simon, David P. Waller, David C. Whritenour
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Abstract
A novel class of bridged indicator dyes is disclosed which possess absorption in the infrared region of the electromagnetic spectrum. These bridged indicator dyes are useful as light-absorbing, pH-sensitive optical filter agents in diffusion transfer photographic processes adapted to be performed in the presence of ambient light and to diffusion transfer products useful in such processes. These indicator dyes will also find utility in titrations and other analytical techniques and products where pH-sensitive indicator dyes are employed and absorption of infrared is useful.
Claims13
A compound having the formula ##STR39## wherein A and B are selected from a first and second carbocyclic aryl radical possessing as a substituent an amino or hydroxy group, said substituent positioned ortho or para to the meso carbon and meta to the bridging carbon, provided further that at least one of said A or B contains as said substituent a hydroxy group and X" represents the carbon atoms necessary to complete a fused polycyclic sulfinate ester ring system;
- provided further that when X" represents the carbon atoms necessary to complete 1,3-dihydro-2,2-dioxidebenzo[c]thiophene, the 1,3-dihydro-2,2-dioxidebenzo[c]thiophene is not substituted in the 7'-position with a group which exerts a steric influence such that the sulfone, at a pH at or above its pKa, remains closed at room temperature.
A compound having the formula ##STR40## wherein C and D represent carbocyclic aryl groups;
- E and E' represent an amino or hydroxy group positioned either ortho or para to the meso carbon and meta to the bridging carbon, provided that at least one of E or E' is hydroxy;
- R.sub.1 and R.sub.2 represent bulky groups or hydrogen, wherein said bulky groups are selected from the group consisting of:
- (1) branched alkyl having at least three carbon atoms;
- (2) a substituted amide represented by ##STR41## or (3) a substituted sulfonamide represented by ##STR42## wherein R' and R" are branched alkyl groups;
- provided at least one of said R.sub.1 and R.sub.2 is one of said bulky groups;
- and X' represents the carbon atoms necessary to complete a fused polycyclic carboxylate ring system or a fused polycyclic sulfinate ester ring system;
- provided further that when X' represents a phthalide or 1,3-dihydro-2,2-dioxidebenzo[c]thiophene, the phthalide or 1,3-dihydro-2,2-dioxidebenzo[c]thiophene is not substituted in the 7'-position with a group which exerts a steric influence such that the lactone or sulfone, at a pH at or above its pKa, remains closed at room temperature.
A compound containing the system represented by ##STR45## wherein X is selected from carboxy or halide.
Dependencies are inferred from the claim text.