TYPES OF LAC MADE BY- kalpana

Lac is a resinous secretion from a scale insect called Lac Insect (Laccifer lacca) as a protective covering that inhabits on Ber (Ziziphus marutiana), Palas (Butea monosperma) and Kusum (Schleichera oleosa).

Classification on the basis of host plants: Rangeeni lac obtained from host plants, Palas, Ber, etc. It is scrapped off the branches with knives. Kusumi lac obtained from plant Kusum. It is cut into bits. The overall production of the Rangeeni lac is 6 to 8 times that of Kusumi as Kusum trees are generally less in no. and distribution but the KUSUMI lac has resin of superior quality.

Classification on the basis of procurement time ARI LAC (immature lac): If lac crops are harvested by cutting down the lac bearing twigs a little before the larval emergence, PHUNKI LAC (empty lac): If lac crops are harvested by after the larval emergence is over.

Classification on the basis of collection month: BAISAKHI JETHWI KATKI AGHANI December to January April to May October to November June to July

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. Composition of stick lac Lac resin - 68% Lac wax - 6% Lac dye - 1% Others - 25%

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

Manufacture of Seedlac The harvested sticklac is crushed and sieved to remove impurities. The sieved material is then repeatedly washed to remove insect parts and other soluble material. The resulting product is sun dried and is known as seedlac. The prefix seed refers to its pellet shape.

Machine for Crushing the Stick Lac.

Washing Machine.

Sun Drying of Washed Seedlac.

Seedlac is further processed into shellac. The manufactured product prepared from stick lac after washing and melting, which takes the form of yellow coloured flakes, is called SHELLAC.

Shellac

Manufacture of Shellac Seedlac is kept in the long bag made up of cloth, is passed gradually in front of a charcoal-fired hearth which melt the Lac. By twisting the bag, molten Lac is squeezed out through cloth. The viscous molten mass is flattened by pressing to make its sheet. This sheet is held near fire and stretched to a tenous, transparent sheet. This tenous sheet is then laid flat away from the fire place to cool and then broken into flakes of shellac.

Hand made processing of Shellacs

Kirilac During formation of shellac when lac is forced squeezed out of bag, impurities such as insect bodies or twigs are left in the bag. The residue left inside this cloth bag is another variety of refuse Lac known as Kirilac.

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

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.

Button lac

Manufacture of Button lac To prepare button lac the molten mass is made more fluid. It is then poured in small quantities in form of buttons. Then these buttons are brought close to heat to make their surfaces glossy and smooth.

Bleached Lac Bleached lac has super characteristics and qualities i.e. adhesive, is non-toxic and physiologically harmless. It is a refined product obtained by chemical treatment. In dry condition it is a hard solid insoluble in water but readily soluble in the lac solvents and produce pale yellow or colorless solutions. It softens readily under hot water but hardens again on cooling. Bleached lac deteriorates quickly and should be used within 2-3 months of manufacture.

Manufacture It is prepared by dissolving shellac or seed lac in aqueous Sodium carbonate solution, bleaching the solution with Sodium hypochlorite and precipitating the resin with Sulphuric acid precipitates are filtered, washed free from acid. the precipitates are either converted into bars or cooled, powered, and dried.

Dewaxed Lac It is bit harder, shines a bit brighter, is completely free from wax. Lac extract is heated to boiling point and the solution is allowed to stand the molten wax floats up and solidification by cooling occurs. This is removed from the lac. Lac obtained is dewaxed one.

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