| 摘要 |
PURPOSE:To perform a sharp marking, by a marking method wherein a laser light is irradiated on the surface of an article made of a material consisting of a boric acid-containing inorganic substance. CONSTITUTION:As a marking material, all boric acid-containing inorganic substances can be used, but a lithium borate anhydride or a calcium borate anhydride is preferably used for especially obtaining superior transparency and color forming properties. The boric acid-containing inorganic substance is incorporated in the amount of 5-80wt.%, preferably 15-60wt.%. If the content is less than 5wt.%, a sharp contrast cannot be obtained. If more than 80wt.%, the physical properties are remarkably deteriorated. A sharp marking can be obtained by irradiating a laser light having a suitable strength on the surface of a resin molded material or resin coated material consisting of the boric acid-containing inorganic substance through a mask. |
