PURPOSE: To obtain the titled ink keeping high adhesivity to an object to be printed and excellent visibility even if the printing object is exposed to a temperature to cause the change in the properties of the colorant, by using a colorant consisting of fine particles of colored glass or fine particles of colored glass composition forming a glass by heat-treatment.

CONSTITUTION: The objective composition is produced by compounding (A) a colorant consisting of fine particles of colored glass or fine particles of colored glass composition mixture forming a glass by heat-treatment, (B) a solvent, (C) a binder and (D) a conductivity-imparting agent. The component A is preferably a material having a melting point falling within the heat-resistant temperature range of the printing object. The glass composition mixture is e.g. Na2O.2 SiO2-Li2O.2SiO2. The colorant for the glass composition mixture is preferably inorganic pigment from the view point of heat-resistance.