| abstract |
Laser-marks (such as indicia, characters, symbols, patterns and the like) of exceptionally clear and thambiguous quality may be inscribed on the surface of an article whose surface region to be laser-marked is formed of a thermoplastic resin composition having a critical oxygen index of 22% or above as determined by ASTM D2863. The entire article may be formed (molded of such a thermoplastic resin composition, or the article may include a non-thermoplastic core having a surface layer thereof of the thermoplastic resin composition. Preferably, the thermoplastic resin composition is a polybutylene terephthalate with one or more flame retardants which impart the requisite critical oxygen index thereto. |