Thursday, October 15, 2009

Shellac Attack

The lac resin has been known since 1500 BC, and it is the only resin of animal origin. The lac (Tachardia lacca) are tiny insects that swarm and live off of host trees in India. They suck sap into the their bodies and excrete a resinous substance through their pores to form a crust on the twigs and branches. The crude lac (or sticklac) is scraped off the trees then dried, crushed, sifted and sorted. Traditionally this process was done by hand, but now can done by machine. When the lac is done being processed it is in flake form, as pictured above. To make shellac, the flakes are dissolved in alcohol. Today you can still buy shellac flakes at specialty store or buy premade shellac at any hardware store.

Shellac (handmade) is all natural and has been utilised for the manufacturing of many products including paint and varnish, a glaze for fruit, coffee beans and nuts, a coating for tablets, as a leather dressing, a sealing wax, as a printing ink, in cosmetics, in confections, as food coloring and polishes. Since shellac has been around for so long, it is found in many historic structures and furniture. Shellac is also best for inside surfaces, and is used in many fine finishing techniques, including french polish.

To test to see if a surface is in fact shellac, dab a small portion of it with denatured alcohol, which is the solvent for shellac. If the surface becomes tacky, it is most probably shellac.

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