Sunday, May 30, 2010

J.F. Royle and the dyes of India

John Forbes Royle (1799-1858) was one of the first to systematically investigate the potential of Indian plants. For economic use that is.
He was superintendant of the botanic garden at Saharanpur from 1823-1831, and succesfully introduces tea. In textile studies his main book is probably "The fibrous plants of India", but in his more general magnum opus on Himalayan flora, he also adds interesting details on dye stuffs.
more to follow..

Tuesday, May 25, 2010

The trade value of old batik in 1889

Just a small note I found in the magazine of the Dutch Colonial Museum (Koloniaal Museum), of januari 1889:
'Als een bewijs hoe in den vreemde het Javaansche batikwerk op prijs gesteld wordt, diene het feit, dat de Ceylonsche handelaren in kramerijen, die te Colombo op de Hollandsche mailbooten hunne waren komen aanbieden, steeds naar Sarongs of Kains (echte) vragen en daarvoor gaarne een relatief groote waarde aan snuisterijen in ruil aanbieden.
A governo voor repatrieerende indische dames die hare oude Sarongs op voordeelige wijze van de hand willen zetten.'

Saturday, May 22, 2010

Weifa: Honey-yellow from Asia's honey-trees

The long hunt for the nature of Lo kao (described below) is in quite a contrast to the story of another dye of Chinese origin: the weifa. As weifa is produced of flower buds, it didn't take more than a good botanical observator (found in Fortune) to identify the nature of the dyeing material. Which turned out to be the 'honey tree', Sophora japonica. Some reports state that the buds are baked, but most reports mentions simple drying (but drying in hot climates may mean something else than in temperate regions..)
First imported after the mission of Isidore Hedde for the French government (1843-46), they were compared to anise seeds, but were already soon discovered by Henon (1847) to be flower buds. Experiments by Lyon silk dyer Guinon showed that the bright yellow dye components turn brown when the flower develops, so early harvesting seems necessary.
It is said that the famous imperial yellow of the emperor's robes was dyed this way, but I have not yet found analytical proof for this.

Friday, May 21, 2010

Lo kao, a lucrative Chinese green of the 19th century

Lo kao (descibed as a greenish indigo) was a true novelty hit in the 1850´s. Until then, the main green dyes were composed of a mixture of yellow and blue dyes. Imperfect mixing led to unstable and not very lightfast colours. Lo kao dyed green without mixing. Before the discovery of its source plants the dye quickly became extremely expensive (the magazine Volksvlijt mentions a price of Dfl. 250 for a pound in 1854). After some experimentation Natalis Rondot found out that the dye was actually decocted from the bark of two related Rhamnus (buckthorn) species, R. utilis and R.chlorophorus. There are several books and articles that demonstrate the intense interest that the discovery caused, starting with Rondot's own Notice du vert de Chine (1858), followed by numerous articles in scientific magazines. A German publication, simply titled Das Chinagrün by Karl Löffler, surfaced in 1861.
A good overview of the research of the French into Chinese silk and its dyeing (and the subsequential interest of the Chinese in French sericulture) is online here: link
It proved a short-lived craze, however. Chemists made a slightly inferior buch much cheaper alternative from the European buckthorn, which, in its turn, was replaced in the 1860's by synthetic rapidly dyeing greens.