Effect of Lac Dye on Mulberry Silk

摘要

Lac dye is a natural colouring matter comprising of Carminic, Kermesic and Laccaic acid and is extracted from sticklac. It is well-known that these are obtained either from exudation or dried bodies of lac insects. These acid compounds are hydro-soluble and non-toxic in nature. Lac dye is fast on animal fibres than on synthetic or vegetable fibres. It is alsornreported that lac dye at the level of 70-75% purity was extensively used for dyeing of wool and silk till the beginning of 20th century, but gradually replaced by synthetic dyes. In the absence of proper utilization, as much as 250 MT of lac dye is being wasted.