Ink composition for marking nonporous substrate

PROBLEM TO BE SOLVED: To provide an ink composition which need not be cured with ultraviolet and is stably usable for marking an object having a nonporous surface by incorporating a specific polymer resin and a hydrophobic polymer resin having a plasticizing effect. SOLUTION: An ink composition which is for use in marking by the continuous jet method and contains no ultraviolet polymerization initiators is obtained by compounding 0.5-10 wt.% at least one dye and/or pigment selected among oil-soluble dyes, pigments, and basic dyes, at least one solvent selected among alcohols, ketones, esters, and aromatic hydrocarbons, a binder, and a conductive salt, the binder comprising at least one polymer resin which is either a hydroxylated resin with a hydroxyl value of 30-100 or a carboxylated resin with an acid value of 40-300, an epoxidized hydrophobic polymer resin having an epoxy content of 1,000-6,000 mmol/kg, and a resin selected among ketone resins, aldehyde resins, rosins, and rosin derivatives. COPYRIGHT: (C)1996,JPO