Common turpentine

Hatchett treated various kinds of wood, coal, and coke with nitric acid and found that a substance very analogous to tannin. . . may at any time be produced by exposing carbonaceous substances, whether vegetable, animal, or mineral, to the action of nitric acid. He also converted skin into leather by means of materials which, to professional men, must appear extraordinary, such as deal sawdust, asphaltum, common turpentine, pit coal, wax candle, and a piece of the same sort of skin.. . . ... 

Colophony—Common Rosin.—This is the residue remaining on the distillation of common turpentine it retains more or less water, and is known as white and yellow resin, being in this state translucent, and often slightly viscid. When deprived of water by fusion, it is termed brown or black resin, colophony, rosin, or fiddler s rosin. 

Resin.—Resides oil and alkali common resin or colophony also forms an important ingredient in the production of soap. The sources and method of procuring this substance have been fully discussed in a separate article, aud it only remains here to treat of it as a constituent of soap. The kind used is that yielded by the common turpentine, produced by and extracted from the several species of pine,, ... 

Kode of PreparatioiL—The oater bark near the root is removed from Pimu palutiritt Fimu i4eda Pinut pinastery as weU as from other varieties of pines. Incisions are then made through the inner bark into the wood, rom which a mixture of volatile oil and resin (crude or common turpentine) flows into a pit dug in the earth, whence it is transferred to casks. B j distillation, with or without water, the volatile oil (oil or spirit of turpentine) is separated from the resin. 

Alum, in fine powder. Common Turpentine Prepared Lard. . . ... 

Common Turpentine. 1 ounce. Prepared Lard.12 ounces. 

Figure 2.2 Chemical structures of the most common turpentine monoterpene components.

A varnish is often appHed on top of the paint layers. A varnish serves two purposes as a protective coating and also for an optical effect that enriches the colors of the painting. A traditional varnish consists of a natural plant resin dissolved or fused in a Hquid for appHcation to the surface (see Resins, natural). There are two types of varnish resins hard ones, the most important of which is copal, and soft ones, notably dammar and mastic. The hard resins are fossil, and to convert these to a fluid state, they are fused in oil at high temperature. The soft resins dissolve in organic solvents, eg, turpentine. The natural resin varnishes discolor over time and also become less soluble, making removal in case of failure more difficult (see Paint and FINNISH removers). Thus the use of more stable synthetic resins, such as certain methacrylates and cycHc ketone resins, has become quite common, especially in conservation practice. 

Camphor, Cj HjgO, occurs in the wood of the camphor tree Laurus camphora) as dextro-camphor. This is the ordinary camphor of commerce, known as Japan camphor, whilst the less common laevo-camphor is found in the oil of Matricaria parthenium. Camphor can also be obtained by the oxidation of borneol or isoborneol with nitric acid. Camphor may be prepared from turpentine in numerous ways, and there are many patents existing for its artificial preparation. Artificial camphor, however, does not appear to be able to compete commercially with the natural product. Amongst the methods may be enumerated the following —... 

Pineneozonide and Pineneoxoozonide. A compn corresponding to something between Cj oHj 03 and Cj 0Hj 604 was obtained by Harries Nere-sheuner (Ref 2) on treating right-rotary turpentine with weak ozone. It could be sepd into thick oily (80—90% of the total) and solid fractions. The mixt was insol in common org solvents, and puffed off when heated on a spatula... 

The terpenoid resins commonly used as artists materials were colophony, Venice turpentine, mastic, dammar, copals and sandarac, and most of the scientific literature concerning the identification of Old Master varnishes and the study of their degradation focuses on these resins. 

Rosin, a brittle solid, mp 80 °C, is obtained from the gum of trees and tree stumps as a residue after steam distillation of the turpentine. It is made of 90% resin acids and 10% neutral matter. Resin acids are tricyclic monocarboxylic acids of formula C20H30O2. The common isomer is 1-abietic acid. About 38% of rosin is used as paper size (its sodium salt), in synthetic rubber as an emulsifier in polymerization (13%), in adhesives (12%), coatings (8%), and inks (8%). 

A common industrial method of a-terpineol synthesis consists of the hydration of a-pinene or turpentine oil with aqueous mineral acids to give crystalline cis-terpin hydrate mp 117°C), followed by partial dehydration to a-terpineol. Suitable catalysts are weak acids or acid-activated silica gel [83]. 

Surface lipids of plants. The thick cuticle (Fig. 1-6) that covers the outer surfaces of green plants consists largely of waxes and other lipids but also contains a complex polymeric matrix of cutin (stems and leaves) or suberin (roots and wound surfaces).135/135a Plant waxes commonly have C10 - C30 chains in both acid and alcohol components. Methyl branches are frequently present. A major function of the waxes is to inhibit evaporation of water and to protect the outer cell layer. In addition, the methyl branched components may inhibit enzymatic breakdown by microbes. Free fatty acids, free alcohols, aldehydes, ketones, 13-dike tones, and alkanes are also present in plant surface waxes. Chain lengths are usually C20 - C35.136 Hydrocarbon formation can occur in other parts of a plant as well as in the cuticle. Thus, normal heptane constitutes up to 98% of the volatile portion of the turpentine of Pin us jeffreyi.81... 

Oil of Turpentine.—This is a common adulterant for the volatile oils and is not always easy to detect. In most cases use is made of the specific gravity, fractional distillation and rotatory power, and the characters of oil of turpentine are described in Chapter IX (see also Oil of Lemon). 

Acetaldehyde has a pungent, suffocating odor that is somewhat fruity and quite pleasant in dilute concentrations. Acetaldehyde is miscible in all proportions with water and most common organic solvents, e.g., acetone, benzene, ethyl alcohol, ether, gasoline, toluene, xylenes, turpentine, and acetic acid. 

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