| abstract |
Abstract of the Disclosure New Hydroquinones New hydroquinones have the formula: (I) wherein p is 1 or 2 and q is 0 or 1, provided that p + q is 1 or 2; R is a residue of formula: (II) wherein Q is selected from the residues -COZR4 wherein Z is O or NR5, -OX wherein X is R5 or -COR7, -NR8R9, -Po(OR10)[O]xR11 wherein x is O or 1, -SO2R12 or -CN, and salts thereof with organic or inorganic acid bases. The groups R1, R2, R3, R4, R5, R7, R8, R9, R10, R11, R12, k and n are defined hereafter. These compounds are used as couplers in photographic materials. |