Patent ID: 8859640

Claim:
A coloring ink for marking dots on an outer surface of an electric wire, containing; 100 parts by weight of an ink material containing 96 parts by weight of at least 99% acetone, 3 parts by weight of poly(methyl methacrylate), and 1 part by weight of a coloring material; and 5-15 parts by weight of an aqueous polyvinyl alcohol solution, wherein the aqueous polyvinyl alcohol solution has a concentration of 10-15% by mass; wherein the coloring ink has a viscosity of at most 10 mPa·s; and wherein the coloring ink has the properties of color irregularity over less than ⅓ the total area of the respective dots, fastness such that the coloring ink of dots does not peel-off in a pressure test repeated 30 times, and merging such that ejected ink entirely covers circumference of the electrical wire to mark the respective dots.