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Tar

This article is about the black liquid. For other uses of this word, see tar (disambiguation).

Tar is a viscous black liquid derived from the destructive distillation of organic matter. Most tar is produced from coal as a byproduct of coke production, but it can also be produced from petroleum, peat or wood. Naturally occurring "tar pits" (e.g. the La Brea Tar Pits in Los Angeles) actually contain asphalt, not tar, and are more accurately known as asphalt pits. In English and French, "tar" means primarily the coal derivative, but in northern Europe, it refers primarily to the wood distillate, which is used in the flavoring of candy (among other things).

Tar was a vital component of the first sealed, or "tarmac", roads. It was also used as seal for roofing shingles and to seal the hulls of ships and boats. It was also used to waterproof sails, but today sails made from naturally waterproof synthetic substances have negated the need for sail sealing.

Wood tar is still used to seal traditional wooden boats and the roofs of historical shingle-roofed churches. Wood tar is also available diluted as tar water . Wood tar has numerous uses:

  • Flavoring for candies (e.g. Terva Leijona ) and alcohol (Terva Viina )
  • Scent for saunas
  • Anti-dandruff agent in shampoo
  • Disinfectant
  • Treatment of psoriasis
  • As a component of cosmetics
07-10-2008 09:35:13
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