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  Introduction to Lac and Lac Culture by Dr. Sailesh Chattopadhyay    

What is lac?

Lac is a natural, biodegradable, non-toxic, odorless, tasteless, hard resin and non-injurious to health.

Lac is, in fact, a resinous protective secretion of tiny lac insect, Kerria lacca (Kerr) which belongs to the family Tachardidae in the super family Coccoidea of the order Hemiptera.  The lac insect is a pest on a number of plants both wild as well as cultivated. The tiny red–colored larvae of lac insect settle on the young succulent shoots of the host plants in myriads and secrete a thick resinous fluid which covers their bodies.  The secretion from the insects forms a hard continuous encrustation over the twigs.

The encrusted twigs are harvested and the encrusted twigs scraped off, dried and processed to yield the lac of commerce which is regarded as Non Wood Forest Product (NWFP) of great economic importance to India.

Ari Lac And Phunki Lac

If lac crops are harvested by cutting down the lac bearing twigs a little before the larval emergence, that lac is known as ARI LAC (immature lac) or after the emergence is over, that is called PHUNKI LAC (empty lac).

Lac And Its Forms

Stick lac: The lac encrustations is separated by knife or broken off with finger from the twig of host plants and is known is STICK LAC or CRUDE LAC or RAW LAC.

Seed lac: The stick lac, after grinding and washing, is called SEED LAC or CHOWRI.

Shellac: The manufactured product prepared from stick lac after washing and melting, which takes the form of yellow colored flakes, is called SHELLAC.

Button lac: After melting process, lac is dropped on a zinc sheet and allowed to spread out into round discs of about 3” diameter and 1/4” thickness is called Button Lac.

Garnet lac: It is prepared form inferior seed lac or kiri by the solvent extraction process. It is dark in color and comparatively free from wax.

Bleached lac: It is a refined product obtained by chemical treatment. It is prepared by dissolving shellac or seed lac in Sodium carbonate solution, bleaching the solution with Sodium hypochlorite and precipitating the resin with sulphuric acid. Bleached lac deteriorates quickly and should be used within 2-3 months of manufacture.

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