coal tar

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tar

[tahr]

a dark brown or black viscid liquid from the wood of various species of pine, or found as a by-product of the destructive distillation of bituminous coal (see coal tar). It is a complex mixture, the source of organic substances such as cresol, creosol, naphthalene, paraffin, phenol, and toluene. Formerly used as an oral medication in treatment of various conditions, it has been found to be toxic and carcinogenic and now has only limited topical use in certain skin diseases.

coal tar a by-product obtained in destructive distillation of bituminous coal; if its fumes are inhaled or if it is ingested in its natural state, it is toxic and carcinogenic. A preparation is used in ointment or solution in treatment of eczema and psoriasis.

coal tar

(kōl tar),

A by-product obtained during the destructive distillation of bituminous coal; a dark semisolid of characteristic naphthalenelike odor and a sharp, burning taste; used to treat skin diseases.

Farlex Partner Medical Dictionary © Farlex 2012

coal tar

A viscous black liquid containing numerous organic compounds that is obtained by the destructive distillation of coal and used as a roofing, waterproofing, and insulating compound and as a raw material for many dyes, drugs, and paints.

A blackish, semisolid by-product of the destructive distillation of bituminous coal, which contains benzene, naphthalene, phenols, and other organic compounds; coal tar is used to treat psoriasis, and may induce clearance of psoriatic plaques
Cons Unpleasant odour, carcinogenic
Coal tar is usually combined with UVB light

coal tar

Therapeutics A blackish, semisolid byproduct of the destructive distillation of bituminous coal, which contains benzene, naphthalene, phenols, and other organic compounds; CT is used to treat psoriasis, and may induce clearance of psoriatic plaques Cons Unpleasant odor, carcinogenic; CT is usually combined with UVB light. See Psoriasis.

coal tar

A complex mixture of organic substances, especially polycyclic hydrocarbons, derived from the distillation of coal. Although the action of this mixture is not well understood, coal tar preparations are used empirically to treat various skin disorders such as ECZEMA and PSORIASIS. The drug is on the WHO official list. It is contained in numerous trade preparations such as Baltar, Capasal, Carbo-Dome, Gelcotar, Pentrax, Polytar, Psoriderm and Tar Band.

Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

References in periodicals archive ?

Full Research Report On Global Coal Tar Market Analysis available at: https://www.millioninsights.com/industry-reports/coal-tar-market-outlook

Coal Tar Market Is Majorly Drive By Rising Demand From Medical & Industrial Segment And Sealing Of Roads Till 2022 / Million Insights

Coal tar pitch is a black, sticky solid material with a very high viscosity [2].

Study on the Pyrolysis Characteristic and the Microstructure of the Pyrolysis Products of [beta] Resins from Different Coal Tar Pitch

'As soon as Islamabad temperature touches 36 centigrade, the coal tar starts melting down and large pieces can be seen everywhere on LED lights covers.

Inquiry on Liaquat Gymnasium's roof leakage initiated

Coal tar yield ([Y.sub.tar]), lighter tar fraction ([f.sub.light]), lighter tar yield ([Y.sub.light tar]), noncondensed pyrolysis gas yield [Y.sub.i], gas yield [Y.sub.gas], char yield [Y.sub.char], and liquid yield [Y.sub.liquid] were calculated using (1) to (7) for the distribution of pyrolysis products.

In Situ Catalytic Pyrolysis of Low-Rank Coal for the Conversion of Heavy Oils into Light Oils

Coal tar pitch is a complex mixture of the residue from the distillation of high temperature coal tar with an approximate softening point of 90 to 180 degree C.

Global Coal Tar Pitch Market - Industry Analysis, Size, Share, Growth, Trends, and Forecast 2016-2021

By ESI coupled to high-field (9.4 T) FT-ICR MS tens of thousands of compounds observed as positive or negative molecular ions from basic or acidic species, respectively, have been resolved and their elemental compositions (CcHhNnOoSs) as well as the degree of saturation (number of rings plus double bonds) in crude oil, shale oil and coal tar and their distillates determined [12-14].

Analysis and identification of oxygen compounds in Longkou Shale Oil and Shenmu coal tar

However, among paving contractors, even in the same city, there can be diametrically opposing views about the performance, cost, health, and environmental pros and cons of coal tar - and asphalt-based sealers.

Studies raise questions about pavement sealers

Noteworthily, institutional investors widely opine that the joint venture will contribute considerably to Ho Tung's performance, partly because of strong consumer demand for detergents in emerging countries, and partly because of maltha, a side product of coal tar, which can be applied to production of anode materials of lithium materials.

Ho Tung aims to become world's second-largest detergent material manufacturer in 2013

This complex is expected to be comprised of three plants including a 250,000 metric ton coal tar distillation plant and two downstream plants producing needle coke and carbon black, added Koppers.

Koppers Inc announces MOU for construction of coal tar carbon products complex in China

"Topical therapy is the bread and butter of psoriasis treatment," and coal tar has been used for centuries to control the symptoms of plaque psoriasis, she said.

Topical coal tar could make a comeback for psoriasis

The most common coating, a coal tar slurry, is used to seal the pavement.

Dealing with spills

Meanwhile, ECHA has released proposals to harmonise within the EU the classification, labelling and packaging of four chemical substances used by the soap and cosmetics sectors: coal tar; coco alkyl amines; hydrogenated tallow alkyl amines; and standard tallow alkyl amines.