| 摘要 |
PURPOSE:To form a secure and sharp mark of a projecting shape on the surface of a thermoplastic resin by a simple method in marking of the surface of the thermoplastic resin by irradiating laser light on the resin surface, moving the laser light, interrupting the irradiation in the foamed state just before the resin evaporates and using the white foam formed in such a manner as the mark. CONSTITUTION:The laser light 2 is irradiated through a lens 4 onto the surface of the thermoplastic resin 1 such as acrylic resin so as to form a focus 3 thereon and is moved. The volatile component such as the unpolymerized monomer or resultant product of decomposition in the resin is foamed by the heating. The laser light is moved and interrupted in a manner as to cease the irradiation just before the volatile component evaporates. The white foamed part formed in such a manner is the mark. The sharp mark of the projecting shape securely sticking to the resin surface is thus obtd. easily and efficiently. |
