Birch-tar
Encyclopedia
Birch-tar
Tar
Tar is modified pitch produced primarily from the wood and roots of pine by destructive distillation under pyrolysis. Production and trade in tar was a major contributor in the economies of Northern Europe and Colonial America. Its main use was in preserving wooden vessels against rot. The largest...

or birch-pitch is a substance (liquid when heated) derived from the dry distillation
Dry distillation
Dry distillation is the heating of solid materials to produce gaseous products . The method may or may not involve pyrolysis/thermolysis. The products are condensed and collected. This method usually requires higher temperatures than classical distillation. The method has been used to obtain...

 of the wood of the birch
Birch
Birch is a tree or shrub of the genus Betula , in the family Betulaceae, closely related to the beech/oak family, Fagaceae. The Betula genus contains 30–60 known taxa...

.

Compounds

It is compounded of guaiacol
Guaiacol
Guaiacol is a naturally occurring organic compound with the formula C6H4. Although it is biosynthesized by a variety of organisms, this colorless aromatic oil is usually derived from guaiacum or wood creosote. Samples darken upon exposure to air and light. Guaiacol is present in wood smoke,...

, phenols
Phenols
In organic chemistry, phenols, sometimes called phenolics, are a class of chemical compounds consisting of a hydroxyl group bonded directly to an aromatic hydrocarbon group...

, cresol
Cresol
Cresols are organic compounds which are methylphenols. They are a widely occurring natural and manufactured group of aromatic organic compounds which are categorized as phenols . Depending on the temperature, cresols can be solid or liquid because they have melting points not far from room...

, xylenol
Xylenol
Xylenol or dimethylphenol is an arene compound with two methyl groups and a hydroxyl group. 6 isomers exist of xylenol of which 2,6-xylenol with both methyl group in an ortho position with respect to the hydroxyl group is the most important...

, and creosol
Creosol
Creosol is an ingredient of creosote. Compared with phenol, creosol is a less toxic disinfectant.-Sources :* Coal tar creosote* Wood creosote* Reduction product of vanillin using zinc powder in strong hydrochloric acid...

.

Uses

Birch-tar was used widely as an adhesive
Adhesive
An adhesive, or glue, is a mixture in a liquid or semi-liquid state that adheres or bonds items together. Adhesives may come from either natural or synthetic sources. The types of materials that can be bonded are vast but they are especially useful for bonding thin materials...

 as early as the late Paleolithic
Paleolithic
The Paleolithic Age, Era or Period, is a prehistoric period of human history distinguished by the development of the most primitive stone tools discovered , and covers roughly 99% of human technological prehistory...

 or early Mesolithic
Mesolithic
The Mesolithic is an archaeological concept used to refer to certain groups of archaeological cultures defined as falling between the Paleolithic and the Neolithic....

 era. It has also been used as a disinfectant, in leather dressing, and in medicine.

Ends of fletching
Fletching
Fletching is the aerodynamic stabilization of arrows or darts with materials such as feathers, each piece of which is referred to as a fletch. The word is related to the French word flèche, meaning "arrow," via Old French; the ultimate root is Frankish fliukka...

 of arrows were fastened on with birch-tar in Mesolithic.

Birch-tar and raw-hide lashings were used to fix the blade of axes
Axes
Axes may refer to:* Axes, woodworking hand tools* The plural of axis* Axes , a 2005 rock album by the British band Electrelane* X and Y axes, or X, Y, and Z axes, perpendicular lines used in the Cartesian coordinate system...

 in Mesolithic.

Birch tar oil
Oil
An oil is any substance that is liquid at ambient temperatures and does not mix with water but may mix with other oils and organic solvents. This general definition includes vegetable oils, volatile essential oils, petrochemical oils, and synthetic oils....

 is an effective repellent
Repellent
Repellent can refer to:* Insect repellent* Animal repellent...

 of gastropods. The repellent effect of sole birch tar oil last about two weeks. The repellent effect of birch tar oil mixed with Vaseline
Vaseline
Vaseline is a brand of petroleum jelly based products owned by Anglo-Dutch company Unilever. Products include plain petroleum jelly and a selection of skin creams, soaps, lotions, cleansers, deodorants and personal lubricants....

 applied on fences lasts up to several months.

Birch tar oil is also used in perfumery as a base note to impart leather and wintergreen
Wintergreen
Wintergreen is a group of plants. Wintergreen once commonly referred to plants that continue photosynthesis throughout the winter...

notes.
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