| abstract |
Said material contains a quinone-type compound which corresponds to one of the formulae (A) or (B) and which is capable in reduced state and under alkaline conditions of releasing a photographically useful group e.g. a dye:n n wherein:n each of (Nuox) 1 and (Nuox) 2 represents an oxidized nucleophilic group, Z represents a bivalent atomic group which is electronegative. Q together with the Z group represents a releasable photographically useful group. each of R', R 2 and R 3 is hydrogen. halogen. alkyl, alkoxy. or an acylamino group or R' and R 2 in adjacent positions on the ring form and ring fused with the remainder of the molecule. or R 2 and R 3 together are fused with the remainder of the molecule. each of R 4 and R 5 represents hydrogen or a hydrocarbon group. n At least one of the substituents R 1 , R 2 . R 3 . R 4 , or R 5 is a ballasting group X. |