The colour fastness to soaping of the silk direct dyeing with tea colour and mordanted dyeing with heamatoxylin coffee, and carthamin already reach to 4 grade or more.

• 试验结果表明：茶叶色素直接上染丝绸，苏木黑、咖啡、红花素经铁盐或铝盐媒染丝绸，皂洗牢度均可达4级或4级以上；