Varnish

Name:
Varnish
Detailed information:
(1) An organic protective coating similar to a paint except that it does not contain a colorant. It may be composed of a vegetable oil (linseed, tung, etc.) and solvent or of a synthetic or natural resin and solvent. In the first case the formation of the film is due to polymerization of the oil and in the second to evaporation of the solvent. “Long-oil” varnishes such as spar varnish have a high proportion of drying oil; “short-oil” types have a lower proportion, i.e., furniture varnishes. Spirit varnishes contain such solvents as methanol, toluene, ketones, etc. and often also thinners such as naphtha or other light hydrocarbon. Flammable.(2) A hard, tightly adherent deposit on the metal surfaces of automobile engines resulting from resinous oxidation products of gasoline and lubricating oils.