Explanation:

Tasar is one of the varieties of natural silk. It stands next to mulbury silk in production as well as quality. There are two varieties of tasar tropical and temperate. Temperate tasar is also known as oak tasar. Morphologically silk consists of two single endless filaments surrounded by silk gum sericin. Tasar contains approximately 5 15 % sericin. Presence of sericin and other impurities imparts a harsh and stiff feel to fabric and also impedes penetration of dyes and other chemicals. Basic preparatory process known as degumming is given to remove sericin from silk. Soap, enzyme, alkali and acid are used for degumming. Removal of sericin enhances luster, smoothness, softness and even dye uptake. Tasar silk is brown to grayish in colour due to the tannin present in oak leaves so it requires preliminary bleaching to impart whiteness.