The leuco phenazine dye 1 wherein said {HEAD ~ electron withdrawing groups} are {TAIL ~ fluorinated alkyl groups} having up to 10 carbon atoms 
are
The leuco phenazine dye 1 wherein said { HEAD ~ electron withdrawing groups } are { TAIL ~ fluorinated alkyl groups } having up to 10 carbon atoms
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH