wood tar

wood tar
a dark viscid product obtained from wood by distillation or by slow burning without flame, used in its natural state to preserve timber, rope, etc., or subjected to further distillation to yield creosote, oils, and a final residuum, wood pitch.
[1855-60]

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      liquid obtained as one of the products of the carbonization, or destructive distillation, of wood. There are two types: hardwood tars, derived from such woods as oak and beech; and resinous tars, derived from pine wood, particularly from resinous stumps and roots. Crude wood tar may be used as fuel or for preserving rope and wood and for caulking. The tar may be fractionated to yield creosote, oils, and pitch.

      Hardwood tars are obtained from pyroligneous acid, either as a deposit from the acid or as a residue from the distillation of the acid. Crude pyroligneous acid is the condensed, volatile product of wood distillation. Resinous wood tars differ from hardwood tar in containing the pleasant-smelling mixture of terpenes known as turpentine. Pine-wood tar, commonly called Stockholm, or Archangel, tar, is made extensively in the forests of Russia, Sweden, and Finland. It is the residue after the turpentine has been distilled, usually with the aid of steam. It is widely used in manufacturing tarred ropes and twine and in impregnating hemp fibre for oakum. In pharmacy, it has some slight use as a component of some ointments and antiseptics. Distillates of pine-wood tar, particularly the creosote fraction, are used in metallurgy in the froth flotation processes.

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Universalium. 2010.

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  • Wood tar — Tar Tar, n. [OE. terre, tarre, AS. teru, teoru; akin to D. teer, G. teer, theer, Icel. tjara, Sw. tj[ a]ra, Dan. ti[ae]re, and to E. tree. [root]63. See {Tree}.] A thick, black, viscous liquid obtained by the distillation of wood, coal, etc., and …   The Collaborative International Dictionary of English

  • Wood tar — Wood Wood, n. [OE. wode, wude, AS. wudu, wiodu; akin to OHG. witu, Icel. vi?r, Dan. & Sw. ved wood, and probably to Ir. & Gael. fiodh, W. gwydd trees, shrubs.] [1913 Webster] 1. A large and thick collection of trees; a forest or grove; frequently …   The Collaborative International Dictionary of English

  • wood tar — wood′ tar n. chem. a dark, viscid wood product used to preserve timber, rope, etc., or distilled to yield creosote, oils, and pitch • Etymology: 1855–60 …   From formal English to slang

  • wood tar — n. a dark, sticky, syruplike substance obtained by destructive distillation of wood and used in the preservation of timber, rope, etc …   English World dictionary

  • wood tar — noun any tar obtained by the destructive distillation of wood • Hypernyms: ↑natural resin • Hyponyms: ↑pine tar * * * noun : tar obtained by the destructive distillation of wood either as a deposit from pyroligneous acid or as a residue from the… …   Useful english dictionary

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  • wood tar — /ˈwʊd ta/ (say wood tah) noun a dark viscid product obtained from wood by distillation or burning slowly without flame, used in its natural state to preserve timber, etc., or subjected to further distillation, when it yields creosote, oils, and a …  

  • wood-tar creosote — noun : creosote 1 …   Useful english dictionary

  • wood-tar pitch — noun : pitch 1b …   Useful english dictionary

  • 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.Types of tarGeneralThe word tar is… …   Wikipedia

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