| 摘要 |
PROBLEM TO BE SOLVED: To obtain an ink compsn. which is excellent in resistances to water and light and hardly blurs by at least incorporating an alkali-soluble colorant, a water-soluble org. solvent, water, and a water-soluble cationic resin obtd. by polymerizing an N,N-dialkylallylamine into the same. SOLUTION: The water-soluble cationic resin has repeating units of formula I and is prepd. by polymerizing an N,N-dialkylallylamine of formula II, if necessary together with another monomer, in water or a polar solvent in the presence of a free-radical polymn. initiator having an azo group and a cationic N [e.g. 2,2'-azobis(2-amidinopropane) dihydrochloride], pref. in an amt. of 25-100 mol% based on the monomer of formula II, neutralizing if necessary or bringing a polymer formed by neutralizing the reaction liquid after polymn., then removing the remaining monomer by distillation, and subjecting the resultant product to purification by ion-exchange film electroldialysis. In the formula, R1 and R2 are each 1-4C alkyl. |
