BISMUTH OXIDE-BASED ADDITIVE FOR LASER MARKING

摘要

The present invention is directed to a bismuth oxide-based additive for laser marking containing oxygen-deficient bismuth oxide represented by the general formula: Bi 2 O (3-x) (provided that x is 0.01 or more and 0.3 or less and x represents the amount of oxygen deficiency calculated according to the formula: x = 3 - O 1s /Bi 4f × 2 from the ratio (O 1s /Bi 4f ) of the peak area attributed to the 1 s electrons of oxygen bonded to bismuth to the peak area attributed to the 4f electrons of bismuth obtained by X-ray photoelectron spectrometry), which enables marking with excellent blackness and contrast without causing undesirable coloration of a resin composition regardless of the type or shape of a resin to be used.