lac insect

Lac is the scarlet resinous secretion of a number of species of insects, namely some of the species of the genera Metatachardia, Laccifer, Tachordiella, Austrotacharidia, Afrotachardina, and Tachardina of the superfamily Coccoidea, of which the most commonly cultivated species is Kerria lacca.^[1]

The above mentioned families are some of the 28 families of scale insects and mealybugs comprising a large group of about 8000 described species of plant sucking insects, a few of which produce similar natural products (e.g., cochineal and crimson). Thousands of these tiny insects colonize branches of suitable host trees and secrete the resinous pigment. The coated branches of the host trees are cut and harvested as sticklac.

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 known as seedlac. The prefix seed refers to its pellet shape. It is used in violin and other varnish and is soluble in alcohol. This type of lac was used in the finishing of 18th century fowling guns in the US. Seedlac which still contains 3-5% impurities is processed into shellac by heat treatment or solvent extraction.

Lac production is found in Assam and other parts of North-East India, Bangladesh, Myanmar, Thailand, Laos, Vietnam and parts of China. It is also found in Mexico.

Host trees

Kerria lacca can be cultivated on either cultivated or wild host trees.

• In India the most common host trees are
  • Dhak (Butea monosperma)
  • Ber (Ziziphus mauritiana)
  • Kusum (Schleichera oleosa)
• In Thailand the most common host trees are
  • Rain tree (Samanea saman)
  • Pigeon pea (Cajanus cajan)
• In China the common host trees include
  • Pigeon pea (Cajanus cajan)
  • Hibiscus species
• In Mexico
  • Barbados nut (Jatropha curcas)

Uses

The use of lac dye goes back to ancient times. It has been used in India as a skin cosmetic and dye for wool and silk. In China it is a traditional dye for leather goods. The use of lac for dye has been supplanted by synthetic dyes. It is used in medicine as hepatoprotective and antiobesity drug.^{[citation needed]}

See also

• Lacquer - A product that was at one time made from lac, but in modern common usage now refers to a separate product with similar properties.
• Shellac - A glaze used on many edible products such as Skittles^[2]

References

1. ^ http://banglapedia.search.com.bd/HT/L_0005.htm Banglapedia: Lac
2. ^ Ingredients of Skittles

External links

• Picture of lac insect
• Drawing of insect, its larva and a colony
• http://www.beadnshop.com/lac-kashmiri-beads/ Beads and other products produced with the help of lac. Manufacturing process and information on site.
• http://www.jatropha.de/ The Jatropha Website, for production in Mexico