Gambir
The Gambir (from the Indonesian , with emphasis on the first syllable), also Gambir catechu- or yellow-catechu called, is a color and tannin , which from the leaves of climbing shrub Uncaria gambir from Malaysia is recovered and Indonesia. Both gambir and the similar catechu from the gerber acacia and other acacia species provide a brown color mostly for cotton and catechu also a black color for silk .
Other or outdated names for gambir are yellow or white, pale catechu , gutta gambir and incorrectly also terra japonica ("Japanese earth"). It is obtained especially in Indonesia on Java and Sumatra as well as in back India , and not like catechu from acacia, but from the young branches and leaves of the red shrub Uncaria gambir . This variety appears partly in cube-shaped dark brown or reddish black, inside a little lighter colored pieces than Singapore Gambir , partly as more yellow-brown, inside also lighter cubes ( Rhiogambir ).
To understand the plant dyes, it should be mentioned that the greater number of these are not contained directly in the relevant plant parts, but are only created from the existing components through a processing process. The actual catechu varieties taste astringent and then sweetish, but the gambir develops bitterness in addition to the astringent taste. The varieties all only partially dissolve in cold water, but should be completely soluble in hot water and the more sediment they leave behind, the more contaminated they are. In combination with chrome and copper salts and other additives, brown colors, mixed colors and real black are produced.
literature
- German Colonial Lexicon. Vol. I (1920): Dyes
- Catechu . In: Merck's Warenlexikon . 3rd ed. 1884 ff., P. 257 f.