Since the first if people want to make a good final look of a product made from wood (wood furniture), then they would superimposing varnish or lacquer as camphor is exclusive image of man since time immemorial. Politer basic ingredients, namely:
o original base material chellac
o shellac factory
o bleached lac
a) The basic ingredients First Shellac
Shellac is obtained from a hard resin called lac, produced from a thin skin of the insects that are in the trees is a kind of fig tree species contained in Bengali, Siam, China, Ceylon, Burma, and the islands of Malacca. This material is known as a pure resin produced directly through insect activity. Many types of female insects which produce shellac, they break through the bark of a fig tree and urged the sap in the stem growth.
Insect migration of liquid droplets of sap to the red pomegranate paste, and then hardened at insect nests. Insect activity continuously, and then finally be able to transform sap into material that surrounds the hard insect nests until its thickness up to ½ “.
b) Shellac Manufacturers
If observed at a glance, from the lac insect that hardens on the surface of a wooden rod fig, can be broken with a range of sizes from 15 to 30 cm, is called the lac stick-lac. Stick-lac eroded by grinding or scraper, separated from the lac insect nests hard and pellet shaped to resemble grains called Seed-Lac. Seed lac is washed free from the old colors and of other objects attached to it.
Once dry, then placed on a cotton cloth bag + 7.5 cm in diameter, with variable length. Both ends of the bag is propped up by a binder and then heated on charcoal embers. With the gradual warming, Lac melted and then spread out to become thin sheets of porcelain that once the cold drum, a thin layer is called Shellac. At the initial softening-dropped shaped wads on cooling formed a sort of pastry palt 5 to 7cm in diameter with a thickness of 3mm.
This is called the button lac, usually labeled plastic dbungkus the lac quality. The initial condition colored lac old and dirty results of the process of melting and purification, in the trade is called garnet lac, Lac Garnet other than as shellac material, also can be used as decoration or diamante red pomegranate.
1) Composition Lac
Percentage of constituents contained in shellac varies depending on the type of tree, place / location, the weather, but in general, the content of shellac material consists of:
Lac resin 65-70%
Lac wax 3-5%
Gluten 4-6%
Dyes 10-12%
The above percentages exclude objects that are not useful. Like a dead insects, dirt and other – other. The existence of lac wax serves as an addition to tensile strength and lower the humidity prisoners. In alkoho mixture, l wax featuring a mix of murky. Lac dye in the original consists of two dyes (dye), a water-soluble, one soluble in spirit. Many water dissolves seed lac dye when washed. At any given time, before the value of shellac resin known. Lac instead harvested / picked to serve as shellac color (dye shellac). But most of shellac dissolved dye with spirit, and if chemically shellac diwax, then the color will be clear shellac.
2) Bleached Lac
Bleached lac used in wood finishing, chemically has an element as decolourant and also result in changes to the quality of the material itself. One way is to boil bleaching watery orange shellac, dissolved in carbone potash and potash will melt settles under the water and wait until it becomes white shellac.
Another method is dissolving shellac in alkali and chlorine gas stream then passes into solution. This is done under water until white. In the event a careful and large commercialized, used sodium hypochlorite and neutralized with acid sulpuric forwarded by filtration and washing.