REFINING OF STICKLAC
Sticklac is converted to commercial grades of Seedlac and Shellac. The yield of refined lac from sticklac varies between 40-60% depending of the host tree, area of cultivation and other factors. apart from lac resin, sticklac contains 6-7% of lac wax, 3-5% water moisture, colouring matter (lac dye), and impurities like insect debris, wood pieces, sand etc.
The refinement of sticklac into seedlac, the semiprocessed material, is mostly carried out in cottage scale or semi-mechanised factories in the lac-growing areas. Seedlac is then converted to shellac of various grades, either by hand-made process in the cottage industries or machine-made process in mechanised industries.
CONVERSION INTO SEEDLAC
Sticklac is first crushed and sieved to remove sand and dust and at the same time rubbing the lac against the sides of the Vat to break open the insect bodies and dissolving the colouring matter in water. The lighter impurities float on the surface and form a scum which can be easily removed. The coloured water containing lac dye is drained out. The washing is repeated until the dye and most of the impurities are removed.
The lac thus cleaned is spread on large, clean, open air
floor to dry. After drying, it is winnowed and sieved to get the commercial variety to seedlac. The dusty lac which is eliminated by sieving is known as Molamma lac and falls under the category of Refuse lac. Molamma contains approximate 55-80%