Patent ID: 8575234

Claim:
An ink composition comprising: a binder resin comprising a copolymer of monomers represented by the following Formula 3a and Formula 3b: wherein n is 2, 3, or 4, and m is 0, 1, or 2; a multifunctional monomer having an ethylenic unsaturated double bond; a coloring agent; a solvent; and a polymerization initiator represented by the following Formula 1: wherein each of R 1 , R 2 , and R 3 is independently hydrogen, halogen, a linear, branched or cyclic alkyl group having 1 to 18 substituted or unsubstituted carbon atoms, a linear, branched or cyclic alkoxy group having 1 to 18 substituted or unsubstituted carbon atoms, an alkylcarbonyl group having 2 to 18 substituted or unsubstituted carbon atoms, an alkoxycarbonyl group having 2 to 18 substituted or unsubstituted carbon atoms, a carboxyl group, a mercapto group, a cyano group, a hydroxyl group, a nitro group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted benzyl group, or a substituted or unsubstituted naphthyl group; and wherein X − is selected from the group consisting of a halogen ion, OH − , ClO 2 − , a sulfonate ion, a sulfate ion, a carbonate ion, a phosphate ion, a fluorophosphate ion, a borate ion, AlCl 4 − , BiF 6 − , a fluoroantimony ion, and a fluoroarsenic ion.