直接染料的硅凝胶固色工艺探讨

通过对 23只常用直接染料进行固色试验,发现硅凝胶能提高绝大多数直接染料的色牢度,对于一些黑色品种效果尤其明显,沾色牢度可以提高 2~3级。硅凝胶是一种极性溶剂,含有大量Si-OH基,可以与黑色染料结构中含有的氨基和羟基相互之间形成氢键。由于形成氢键后会影响互变异构体的平衡,少数染料的色光会有改变。

Fixation of direct dyes with silica gel

Fixation of 23 common direct dyes is carried out with silica gel. It is found that silica gel can improve the color fastness of direct dyes, especially for the black dyes, the color fastness to staining can enhance 2~3 levels. The contained amino group and hydroxyl group in black dyes can form hydrogen bond with Si-OH group contained in polar silica gel. But the formation of hydrogen bond will destroy the balance between the tautomers, which will lead to color change.