Gala

Gala (Shellac) solution of lac in alcohol or acetone. Commercially, the name can be applied to the resinous substance (lac) itself rather than to the solution. The lac is a resin derived from secretions of the female lac insect (Laccifer lacca). The insects feed on the sap of the twigs of certain tropical trees like Kul (Zizyplus mauritiana), Dumur (Ficus hispida), Asathwa (Ficus religiosa), Palash (Butea monosperma), Kusum (Schleichera oleosa), Khoyer (Acacia catechu) etc; some of which are cultivated for this purpose.

The resinous secretion hardens upon exposure to air and forms a protective incrustation around the female young, which are thus held fast to the twigs. The twigs are scraped to remove the incrustation; this crude lac material is known as stick lac. If the stick is crushed, the wood splinters. Then, other foreign materials are removed. Next, the red colouring matter produced by the insects is dissolved out. The residue, when dried, is seed lac. Seed lac is melted, filtered and stretched into thin sheets, which are broken into flakes when cool. Gala is prepared from these flakes by dissolving them in alcohol. Gala varies in colour from dark amber to almost black; the palest one is orange lac and is the most valuable. Gala may be bleached; the product being known as white gala. Bleached gala takes delicate shades of colour and are dyed yellow for ornaments. Applied to surfaces such as wood and plaster, the solution forms a hard coating upon evaporation of the solvent. Gala is widely used as spirit varnish, protective covering for drawings and plaster casts, for stiffening in the manufacture of felt hats, in making sealing wax, and in electrical insulation. It is an essential ingredient in phonographic records, in artificial fruit, and flowers and various other articles.

India is regarded as the principal lac and gala producing country of the world, although some is obtained from other areas in Southeast Asia like Myanmar, Thailand, Sri Lanka, Indonesia and Malaysia. In Bangladesh, nawabganj district is the main area where stick lac is produced. In Talaimari area of Rajshahi City, there are a number of units of cottage industries where gala is extracted from stick lac. [Md Mahbub Murshed]

See also lac dye;lac insect. [Murshed, Md Mahbub Assistant Professor of Geography and Environment, Chittagong University]