Science Fair Project Encyclopedia
Shellac
Shellac is a secretion of the lac insect Coccus lacca, found in the forests of Assam and Thailand. Freed from wood it is called "seedlac."
It is soluble in alkaline solutions such as ammonia, sodium borate, sodium carbonate, and sodium hydroxide, and also in various organic solvents.
When dissolved in acetone or alcohol, shellac yields a varnish of superior gloss and hardness. Orange shellac is bleached with sodium hypochlorite solution to form white shellac.
Shellac was also used in the production of gramophone records until ca. 1950. See gramophone record for details.
See also:
10-26-2009 08:16:03
The contents of this article is licensed from www.wikipedia.org under the GNU Free Documentation License. Click here to see the transparent copy and copyright details
The contents of this article is licensed from www.wikipedia.org under the GNU Free Documentation License. Click here to see the transparent copy and copyright details