The structure of the reduced form of the dye can be represented by the general formula: ##STR1## wherein R1 represents a member selected from the group consisting of aryl groups having up to 14 carbon atoms and containing from 1 to 5 electrons withdrawing substituents, {HEAD ~ alkyl groups} having up to 4 carbon atoms and containing {TAIL ~ one or more electron} withdrawing groups, certain electron withdrawing groups containing a ##STR2## moiety, and certain electron withdrawing groups containing a NH moiety 
The structure of the reduced form of the dye can be represented by the general formula : # # STR1 # # wherein R1 represents a member selected from the group consisting of aryl groups having up to 14 carbon atoms and containing from 1 to 5 electrons withdrawing substituents , { HEAD ~ alkyl groups } having up to 4 carbon atoms and containing { TAIL ~ one or more electron } withdrawing groups , certain electron withdrawing groups containing a # # STR2 # # moiety , and certain electron withdrawing groups containing a NH moiety
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH