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The earliest known lacquers were made in Japan, China and India, perhaps as many as 7,000 years ago. These lacquers, made from urushiol, the sapSap is: tree sap A small, blunt object used as a weapon, often constructed from a bag filled with loose, heavy objects such as lead shot or coins. A tunnel or trench made by sapping . Sap is a 1992 EP by Alice in Chains. Colloquially, a sap is a weak or g of the lacquer treeToxicodendron is a small genus of woody shrubs and vines, all of which produce a skin-irritating oil, urushiol, which can cause a severe allergic reaction; hence the scientific name which means "poison tree". Members of this genus are very often included or varnish treeToxicodendron is a small genus of woody shrubs and vines, all of which produce a skin-irritating oil, urushiol, which can cause a severe allergic reaction; hence the scientific name which means "poison tree". Members of this genus are very often included, produce very hard, durable finishes that are both beautiful, and very resistant to damage by water, acid or abrasion. They do not, however, stand up well to ultraviolet light. Urushiol-based lacquers differ from most other lacquers in that they are slow-drying, and dry by oxidation rather than evaporationEvaporation is the process whereby atoms or molecules in a liquid state (or solid state if the substance sublimes) gain sufficient energy to enter the gaseous state. The thermal motion of a molecule must be sufficient to overcome the surface tension of th. Lacquer skills became very highly developed in India and Asia, and many highly decorated pieces were produced.
Imitations of Asian and Indian lacquer work became popular in England, France, the Netherlands, and Spain in the 17th century. The European technique, which is used on furniture and other objects, uses varnishes that have a resin base similar to shellac. The technique, which became known as japanning, involves applying several coats of varnish which are each heat-dried and polished.
Quick-drying solvent-based lacquers that contain nitrocelluloseNitrocellulose Cellulose nitrate guncotton is a highly flammable compound formed by nitrating cellulose (e. through exposure to nitric acid or powerful nitrating agent). Uses Nitrocellulose was used until World War II as a smokeless propellant, replacing, a natural resin obtained from cottonCotton is a soft fibre that grows around the seeds of the cotton plant. The fibre is most often spun into thread and used to make a soft, breathable textile. Cotton is a valuable crop because only about 10% of the raw weight is lost in processing. Once tr, were developed in the early 1920s, and extensively used in the automobile industry for 30 years. These lacquers are also used on musical instruments and other objects. The hardened finish dissolves in the solvent, and each coat of lacquer dissolves some of the previous coat. These lacquers were a huge improvement over earlier automobile finishes, both in ease of application, and in color retention. The preferred method of applying quick-drying lacquers is by spraying, and the development of nitrocellulose lacquers led to the first extensive use of spray guns. Nitrocellulose lacquers produce a very hard yet flexible, durable finish that can be polished to a high sheen. Drawback of these lacquers include the hazardous nature of the solvent, which is flammable, volatile and toxic, and the hazards of nitrocellulose, which is also used to make explosives.