To improve solubility in a ketone solvent by associating a cationic dye with a counter ion containing either a specific highly fluorinated alkylsulfonylmethide or a specific highly fluorinated alkylsulfonylimide.

A cationic dye is associated with a methide anion having at least two different, highly fluorinated or perfluorinated alkylsulfonyl groups (a) each having a 1-20C linear, branched, or cyclic alkyl or with an imide anion having at least one of the groups (a), and is then dissolved in a ketone solvent.