dimethine z 1 z 2 z 3 z 4 z 5 and z 6 independently represent the atoms chosen from c n o and s necessary to form a substituted or unsubstituted 5 or 6 membered ring preferably z 1 z 2 z 3 z 4 z 5 and z 6 independently represent a substituted or unsubstituted ketomethylene ring a substituted or unsubstituted pyrazolinone n is an integer of at least 2 preferably n is an integer of at least 2 to no more than 400 000 more preferably n is an integer of at least 2 and no more than 100 even more preferably n is an integer of at least 2 to no more than 20 most preferably n is an integer of at least 2 to no more than 5 x is a counter ion used to balance the charge of the molecule particularly preferred counter ions include but are not limited to halide clo 4 bf 4 p ch 3 c 6 h 4 so 3 it would be apparent from the disclosure that l excludes gelatin hydrophilic colloid or protein the recitation 34 atoms chosen from c n o and s necessary to from a 5 or 6 membered ring 34 or the equivalent thereof refers to substituted or unsubstituted rings fused rings may be mentioned as included aromatic and.