| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a chromatic color coloring agent for multicolor color developing laser marking, which can mark with at least two color tones different from each other by irradiating positions different from each other of a molded body with at least two laser beams having energies different from each other, a polymer composition for multicolor color developing laser marking, which can produce, for example, a chromatic color marking resulting from the coloring agent and a white marking on the surface of a molding, the ground color of which is black or one in dark color base, a laser marking method, a molding with multicolor markings or the like. <P>SOLUTION: This chromatic color coloring agent has an exothermic peak, which is ascertained by a differential thermal analysis and has a range of 360°C-590°C. This composition for laser marking includes the chromatic color coloring agent, a black substance (such as carbon black), which itself disappears or which discolors upon the receipt of laser beams, and a polymer under the condition that the contents of the chromatic color coloring agent and of the black substance are respectively 0.001-3 parts by mass and 0.01-2 parts by mass to 100 parts by mass of the polymer. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
