Water-borne pigment-containing ink composition for central core type marking pen

摘要

A central core type marking pen which has an ink storage portion of a central core and a pen tip connected thereto, wherein the central core contains a water-based pigment-containing ink composition which contains a thickening agent and exhibits, at 20° C., a viscosity of not less than 45 mPa.s and not greater than 12 mPa.s when a stress of 0.01 and a stress of 10 Pa are applied, respectively.