The natural haematochrome extracted from plum skin is a kind of safe and non - poisonous colorant.

从李子皮中提取天然红色是一种安全毒食用色。

If the hair graying is inreversible, hair colorant is the main choice for the masking of hair color change.

法逆转发变灰情况下，着色剂是发颜色主要方法。

This article describes the use of organic colorants as the optical recording media, such as polymethine cyanine, phthalocyanine, naphthocquinone and photochromic compounds.

介绍了用作光学记录介质有机染料,如多甲川菁、酞菁、荼醌以及光变色化合物等。