| 摘要 |
<p>PURPOSE:To obtain the subject pigment. comprising neodymium, ytterbium and an organic substance and capable of satisfying a sufficient luminous output in carrying out the reading at a high speed. CONSTITUTION:This pigment comprises (A) neodymium, (B) ytterbium and (C) an organic substance. Furthermore, the rise time for the pigment to attain 90% luminous intensity after the excitation with infrared rays is <=100mu sec and the primary particle diameter thereof is <=80% based on the infrared wavelength. Furthermore, the pigment comprises (D) a carboxylic acid complex salt of cinnamic acid with the components (A) and (B) and the molar fraction (Nd) of the component (A) and the molar fraction (Yb) of the component (C) are preferably at a ratio of (90:10)<=Nd:Yb<=(50:50).</p> |
