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