Dammar gum
Dammar, also called dammar gum, or damar gum, is a
triterpenoid resin, containing many triterpenes and their oxidation products. Many of them are low molecular weight compounds (dammarane, dammarenolic acid, oleanane, oleanonic acid, etc.), which easily oxidizes and photoxidizes.[1]
Types
- Damar mata kucing (‘cat's eye damar’) is a crystalline resin, usually in the form of round balls. Shorea javanica is an important source in Indonesia.[citation needed]
- Damar batu (‘stone damar’) is stone or pebble-shaped, opaque dammar collected from the ground.[citation needed]
- Damar hitam (‘black damar’)
Uses
- Dammar varnish, made from dammar gum dissolved in turpentine, was introduced as a picture varnish in 1826;[2] commonly used in oil painting, both during the painting process and after the painting is finished.[3] Dammar varnish and similar gum varnishes auto-oxidize and yellow over a relatively short time regardless of storage method; this effect is more pronounced on paintings stored in darkness than with works on display in light due to the bleaching effects of sunlight on the colorants involved.[4]
- Batik is made from dammar crystals dissolved in molten paraffin wax, to prevent the wax from cracking when it is drawn onto silk or rayon.[citation needed]
- Encaustic Paints are made from dammar crystals in beeswax with pigment added. The dammar crystals serve as a hardening agent.[5]
- As caulk for ships in the past, frequently with pitch or bitumen.[6]
- As a common mounting material along with light microscopy.[7]
- Used in Ayurvedic medicine for various conditions.[8]
Constituent compounds
Fresh dammar gum consists of a mixture of compounds; primarily hydroxydammarenone, dammarenolic acid, and oleanonic aldehyde.[4]
Material safety
Physical data
- Appearance: white powder
- Melting point: approx. 120 °C
- Density: 1.04 to 1.12 g/ml
- 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[citation needed], probably combustible and incompatible with strong oxidising agents. Its toxicity is low, but inhalation of dust may cause allergies.
See also
- Agathis (Araucariaceae), synonym Dammara
- Canarium strictum (Burseraceae), source of black dammar in South Asia
- Kauri gum, from Agathis australis
- Shorea hypochra (Dipterocarpaceae), source of dammar temak
- Shorea robusta (Dipterocarpaceae), source of sal dammar
- Vateria indica (Dipterocarpaceae), source of white dammar in South Asia
References
- doi:10.1002/jms.893
- ^ William Theodore Brannt (1893). Varnishes, lacquers, printing inks and sealing-waxes: their raw materials and their manufacture. H.C. Baird & Co. p. 168.
- ISBN 0-670-83701-6.
- ^ .
- )
- ISSN 0003-276X.
- ^ MD(Ayu), Dr J. V. Hebbar (2015-04-24). "Sarja - Vateria indica Uses, Dose, Research, Side Effects". Easy Ayurveda. Retrieved 2022-08-11.
Further reading
- Simon, Julia (19 October 2019). "Could This Tree Be an Eco-Friendly Way to Wean Indonesian Farmers Off Palm Oil?". All Things Considered. NPR. Retrieved 20 October 2019.