Alcoholic solution of sulphonic acid-containing copolymer dyed with basic dye

摘要

A coloring material comprising a solution of an alcohol-soluble resin having a sulfonic acid group or a salt thereof, which is dyed with a basic dye, in a solvent comprising an alcohol as a main component. The coloring material is prepared either by (a) polymerizing an ethylenically unsaturated sulfonic acid or a salt thereof in water and adding a basic dye to the obtained aqueous liquid of the formed polymer or (b) carrying out said polymerization in the presence of a basic dye, and dissolving (i) the obtained aqueous liquid of the formed colored polymer of (ii) a colored polymer obtained by removing water from the obtained aqueous liquid of the formed colored polymer in a solvent comprising an alcohol as a main component; or, (a') carrying out said polymerization in a solvent comprising an alcohol as a main component and then adding a basic dye to the obtained polymer solution, or (b') carrying out said polymerization in the presence of a basic dye.