Misplaced Pages

Copal

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.

A resin is a solid or highly viscous liquid that can be converted into a polymer . Resins may be biological or synthetic in origin, but are typically harvested from plants. Resins are mixtures of organic compounds , and predominantly terpenes . Well known resins include amber , hashish , frankincense , myrrh and the animal-derived resin, shellac . Resins are commonly used in varnishes , adhesives , food additives , incenses and perfumes .

#225774

18-404: Copal is a tree resin , particularly the aromatic resins from the copal tree Protium copal ( Burseraceae ) used by the cultures of pre-Columbian Mesoamerica as ceremonially burned incense and for other purposes. More generally, copal includes resinous substances in an intermediate stage of polymerization and hardening between "gummier" resins and amber . Copal that is partly mineralized

36-412: A drop of a solvent such as acetone or chloroform is placed on it. African copal and the kauri gum of New Zealand are also procured in a semi-fossil condition. Rosin is a solidified resin from which the volatile terpenes have been removed by distillation. Typical rosin is a transparent or translucent mass, with a vitreous fracture and a faintly yellow or brown colour, non-odorous or having only

54-456: A slight turpentine odour and taste. Rosin is insoluble in water, mostly soluble in alcohol, essential oils , ether , and hot fatty oils. Rosin softens and melts when heated and burns with a bright but smoky flame. Rosin consists of a complex mixture of different substances including organic acids named the resin acids . Related to the terpenes, resin acid is oxidized terpenes. Resin acids dissolve in alkalis to form resin soaps , from which

72-459: Is a cognate of the Greek ῥητίνη rhētínē "resin of the pine", of unknown earlier origin, though probably non- Indo-European . The word "resin" has been applied in the modern world to nearly any component of a liquid that will set into a hard lacquer or enamel -like finish. An example is nail polish. Certain "casting resins" and synthetic resins (such as epoxy resin ) have also been given

90-593: Is known as copaline . It is available in different forms; the hard, amber-like yellow copal is a less expensive version, while the milky-white copal is more expensive. The word "copal" is derived from the Nahuatl language word copalli , meaning "incense". Subfossil copal is well known from New Zealand ( kauri gum from Agathis australis ( Araucariaceae )), Japan , the Dominican Republic , Colombia , and Madagascar . It often has inclusions and

108-480: Is sometimes sold as "young amber". When it is treated or enhanced in an autoclave (as is sometimes done to industrialized Baltic amber) it is used for jewelry. In its natural condition copal can be easily distinguished from old amber by its lighter citrine colour and its surface getting tacky with a drop of acetone or chloroform . Copal resin from Hymenaea verrucosa ( Fabaceae ) is found in East Africa and

126-700: Is used by honey bees to seal small gaps in their hives, while larger gaps are filled with beeswax. Shellac is an example of an insect-derived resin. Asphaltite and Utah resin are petroleum bitumens . Human use of plant resins has a very long history that was documented in ancient Greece by Theophrastus , in ancient Rome by Pliny the Elder , and especially in the resins known as frankincense and myrrh , prized in ancient Egypt . These were highly prized substances, and required as incense in some religious rites. The word resin comes from French resine , from Latin resina "resin", which either derives from or

144-434: Is used in incense. East Africa apparently had a higher amount of subfossil copal, which is found one or two meters below living copal trees, from roots of trees that may have lived thousands of years earlier. This subfossil copal produces a harder varnish. By the 18th century, Europeans found it to be a valuable ingredient in making a good wood varnish . It became widely used in the manufacture of furniture and carriages. It

162-614: The Aleppo Pine is used to flavour retsina , a Greek resinated wine . While animal resins are not as common as either plant or synthetic resins some animal resins like lac (obtained from Kerria lacca ) are used for applications like sealing wax in India , and lacquerware in Sri Lanka . Many materials are produced via the conversion of synthetic resins to solids. Important examples are bisphenol A diglycidyl ether , which

180-434: The family Dipterocarpaceae , dragon's blood from the dragon trees ( Dracaena species), elemi , frankincense from Boswellia sacra , galbanum from Ferula gummosa , gum guaiacum from the lignum vitae trees of the genus Guaiacum , kauri gum from trees of Agathis australis , hashish (Cannabis resin) from Cannabis indica , labdanum from mediterranean species of Cistus , mastic (plant resin) from

198-542: The majority by the end of that century. Copal is still used by a number of indigenous peoples of Mexico and Central America as an incense, during sweat lodge ceremonies and sacred mushroom ceremonies. Resin Resins protect plants from insects and pathogens, and are secreted in response to injury. Resins confound a wide range of herbivores, insects, and pathogens, while the volatile phenolic compounds may attract benefactors such as predators of insects that attack

SECTION 10

#1732790932226

216-530: The mastic tree Pistacia lentiscus , myrrh from shrubs of Commiphora , sandarac resin from Tetraclinis articulata , the national tree of Malta, styrax (a Benzoin resin from various Styrax species) and spinifex resin from Australian grasses. Amber is fossil resin (also called resinite) from coniferous and other tree species. Copal, kauri gum, dammar and other resins may also be found as subfossil deposits. Subfossil copal can be distinguished from genuine fossil amber because it becomes tacky when

234-688: The name "resin". Some naturally-derived resins, when soft, are known as 'oleoresins', and when containing benzoic acid or cinnamic acid they are called balsams. Oleoresins are naturally-occurring mixtures of an oil and a resin; they can be extracted from various plants. Other resinous products in their natural condition are a mix with gum or mucilaginous substances and known as gum resins . Several natural resins are used as ingredients in perfumes, e.g., balsams of Peru and tolu, elemi, styrax, and certain turpentines. Other liquid compounds found inside plants or exuded by plants, such as sap , latex , or mucilage , are sometimes confused with resin but are not

252-652: The plant. Most plant resins are composed of terpenes . Specific components are alpha-pinene , beta-pinene , delta-3 carene , and sabinene , the monocyclic terpenes limonene and terpinolene , and smaller amounts of the tricyclic sesquiterpenes , longifolene , caryophyllene , and delta-cadinene . Some resins also contain a high proportion of resin acids . Rosins on the other hand are less volatile and consist of diterpenes among other compounds. Examples of plant resins include amber , Balm of Gilead , balsam , Canada balsam , copal from trees of Protium copal and Hymenaea courbaril , dammar gum from trees of

270-741: The resin acids are regenerated upon treatment with acids. Examples of resin acids are abietic acid (sylvic acid), C 20 H 30 O 2 , plicatic acid contained in cedar, and pimaric acid , C 20 H 30 O 2 , a constituent of galipot resin. Abietic acid can also be extracted from rosin by means of hot alcohol. Rosin is obtained from pines and some other plants , mostly conifers . Plant resins are generally produced as stem secretions, but in some Central and South American species of Dalechampia and Clusia they are produced as pollination rewards, and used by some stingless bee species in nest construction. Propolis , consisting largely of resins collected from plants such as poplars and conifers ,

288-482: The same. Saps, in particular, serve a nutritive function that resins do not. Plant resins are valued for the production of varnishes , adhesives , and food glazing agents . They are also prized as raw materials for the synthesis of other organic compounds and provide constituents of incense and perfume . The oldest known use of plant resin comes from the late Middle Stone Age in Southern Africa where it

306-669: Was also sometimes used as a picture varnish. By the late 19th and early 20th century, varnish manufacturers in England and America were using it on train carriages, greatly swelling its demand. In 1859, Americans consumed 68% of the East African trade, which was controlled through the Sultan of Zanzibar , with Germany receiving 24%. The American Civil War and the creation of the Suez Canal led to Germany, India, and Hong Kong taking

324-460: Was used as an adhesive for hafting stone tools. The hard transparent resins, such as the copals, dammars , mastic , and sandarac , are principally used for varnishes and adhesives, while the softer odoriferous oleo-resins ( frankincense , elemi , turpentine , copaiba ), and gum resins containing essential oils ( ammoniacum , asafoetida , gamboge , myrrh , and scammony ) are more used for therapeutic purposes, food and incense . The resin of

#225774