Difference between revisions of "Unki"
Jump to navigation
Jump to search
(username removed) |
|||
| (One intermediate revision by one other user not shown) | |||
| Line 1: | Line 1: | ||
== Description == | == Description == | ||
| − | A bright yellow natural dyestuff obtained from the fruit of the ''Gardinia florida'' that is native to the East Indies (Hofenk-de Graaf 1969). Unki has been used to dye silk a bright yellow color. The primary colorant in unki is [ | + | A bright yellow natural dyestuff obtained from the fruit of the ''Gardinia florida'' that is native to the East Indies (Hofenk-de Graaf 1969). Unki has been used to dye silk a bright yellow color. The primary colorant in unki is [[crocetin|crocetin]]. Crocetin is a substantive dye that is also found in [[saffron|saffron]]. |
| − | == | + | ==Physical and Chemical Properties== |
| − | Crocetin is soluble in water, ethanol, alkali solutions. Crocetin forms a blue solution in concentrated sulfuric acid. | + | * Crocetin is soluble in water, ethanol, alkali solutions. |
| + | * Crocetin forms a blue solution in concentrated sulfuric acid. | ||
| − | == | + | ==Resources and Citations== |
| − | J.Hofenk-de Graaf, ''Natural Dyestuffs: Origin, Chemical Constitution, Identification'', Central Research Laboratory for Objects of Art and Science, Amsterdam, September 1969. | + | * J.Hofenk-de Graaf, ''Natural Dyestuffs: Origin, Chemical Constitution, Identification'', Central Research Laboratory for Objects of Art and Science, Amsterdam, September 1969. |
[[Category:Materials database]] | [[Category:Materials database]] | ||
Latest revision as of 09:32, 23 June 2022
Description
A bright yellow natural dyestuff obtained from the fruit of the Gardinia florida that is native to the East Indies (Hofenk-de Graaf 1969). Unki has been used to dye silk a bright yellow color. The primary colorant in unki is Crocetin. Crocetin is a substantive dye that is also found in Saffron.
Physical and Chemical Properties
- Crocetin is soluble in water, ethanol, alkali solutions.
- Crocetin forms a blue solution in concentrated sulfuric acid.
Resources and Citations
- J.Hofenk-de Graaf, Natural Dyestuffs: Origin, Chemical Constitution, Identification, Central Research Laboratory for Objects of Art and Science, Amsterdam, September 1969.