The dyes have {HEAD ~ the general formulae}: ##STR1## wherein the various substituents, R1 and {TAIL ~ R2} are each selected from hydrogen and a wide variety of groups such as lower alkyl, CN, halogen, and the like, R3 and R4 are each selected from hydrogen, lower alkyl, benzyl and phenyl, and Z represents the atoms necessary to complete a five or six membered ring 
wherein
The dyes have { HEAD ~ the general formulae } : # # STR1 # # wherein the various substituents , R1 and { TAIL ~ R2 } are each selected from hydrogen and a wide variety of groups such as lower alkyl , CN , halogen , and the like , R3 and R4 are each selected from hydrogen , lower alkyl , benzyl and phenyl , and Z represents the atoms necessary to complete a five or six membered ring
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH REL OTH OTH OTH OTH OTH OTH 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 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