Dammar gum

Dammar gum
Dammar resin from the tree Canarium strictum

Dammar gum is obtained from the Dipterocarpaceae family of trees in India and East Asia, principally those of the genera Shorea, Balanocarpus or Hopea. Most is produced by tapping trees; however, some is collected in fossilized form from the ground. The gum varies in colour from clear to pale yellow, while the fossilized form is grey-brown. Dammar gum is a triterpenoid resin, containing a large number of triterpenes and their oxidation products. Many of them are low molecular weight compounds (dammarane, dammarenolic acid, oleanane, oleanonic acid, etc.), but dammar also contains a polymeric fraction, composed of polycadinene.[1]

It is used in foods, as either a clouding or a glazing agent, in the making of incense, varnishing and in other processes. Dammar was first introduced as a picture varnish in 1826, and is commonly referred to as dammar varnish. The varnish, made from dammar gum and turpentine[2] is commonly used in oil painting, both during the painting process and after the painting is finished.[3]

The name is a Malay word meaning "resin" or "torch made from resin".

There are two further types of damar, besides the gum:

  • Mata kucing ("cat's eye") is a crystalline resin usually in the form of round balls.
  • Batu ("stone") is the name given to the stone or pebble-shaped opaque damar collected from the ground.

Contents

Material safety

Physical data

  • Appearance: white powder
  • Melting point: approx. 120 °C
  • Density (kg per m3): 1.04-1.12
  • Water solubility: xylene
  • Refractive index: approx. 1.5
  • CAS number: 9000-16-2
  • EINECS: 232-528-4
  • Harmonised Tariff: 1301-90

Stability and toxicity

The gum is stable, probably combustible, and incompatible with strong oxidizing agents. Its toxicity is low, but inhalation of dust may cause allergies


References

  1. ^ Scalarone, D.; Duursma, M. C.; Boon, J. J.; Chiantoire, O. MALDI-TOF mass spectrometry on cellulosic surfaces of fresh and photo-aged di- and triterpenoid varnish resins. J. Mass. Spec. 2005, 40, 1527-1535. DOI: 10.1002/jms.893
  2. ^ William Theodore Brannt (1893). Varnishes, lacquers, printing inks and sealing-waxes: their raw materials and their manufacture. H. C. Baird & co.. p. 168. http://books.google.com/books?id=JMPvAAAAMAAJ&dq=dammar%20varnish&pg=PA168#v=onepage&q=dammar%20varnish&f=false. 
  3. ^ Mayer, Ralph (1991). The Artist's Handbook of Materials and Techniques (5th ed.). Viking Adult. ISBN 0-670-83701-6). 

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Look at other dictionaries:

  • Dammar — Dam mar, Dammara Dam ma*ra, n. [Jav. & Malay. damar.] An oleoresin used in making varnishes; dammar gum; dammara resin. It is obtained from certain resin trees indigenous to the East Indies, esp. {Shorea robusta} and the dammar pine. [1913… …   The Collaborative International Dictionary of English

  • Dammar pine — Dammar Dam mar, Dammara Dam ma*ra, n. [Jav. & Malay. damar.] An oleoresin used in making varnishes; dammar gum; dammara resin. It is obtained from certain resin trees indigenous to the East Indies, esp. {Shorea robusta} and the dammar pine. [1913 …   The Collaborative International Dictionary of English

  • Gum — or GUM may refer to:Confectionary* Chewing gum * Functional chewing gum or Functional gum * Bubble gum * Wine gum * Gumdrop * Gum base * Gum industryNatural gums* Gum anima * Gum arabic * Cassia gum * Dammar gum * Gellan gum * Guar gum * Locust… …   Wikipedia

  • dammar resin — noun any of various hard resins from trees of the family Dipterocarpaceae and of the genus Agathis; especially the amboyna pine • Syn: ↑dammar, ↑gum dammar, ↑damar • Hypernyms: ↑natural resin …   Useful english dictionary

  • gum dammar — dammar (def. 1). [1865 70] * * * …   Universalium

  • gum dammar — noun any of various hard resins from trees of the family Dipterocarpaceae and of the genus Agathis; especially the amboyna pine • Syn: ↑dammar, ↑damar, ↑dammar resin • Hypernyms: ↑natural resin * * * noun or …   Useful english dictionary

  • dammar — /dam ahr, euhr, deuh mahr /, n. 1. Also called gum dammar. a copallike resin derived largely from dipterocarpaceous trees of southern Asia, esp. Malaya and Sumatra, and used chiefly for making colorless varnish. 2. any of various similar resins… …   Universalium

  • gum damar — noun see gum dammar …   Useful english dictionary

  • dammar —   n. kauri gum; several other resins from Australian and E Indian trees …   Dictionary of difficult words

  • Natural gum — Natural gums are polysaccharides of natural origin, capable of causing a large viscosity increase in solution, even at small concentrations. In the food industry they are used as thickening agents, gelling agents, emulsifying agents, and… …   Wikipedia

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