Vegetable dyes

Also, the cost of dyeing cotton with natural vegetable dyes is 31—77/kg compared to a synthetic approach costing 35 cents /kg. In short, the use of natural vegetable dyes to color the world s textiles is both environmentally and logisticaHy impossible (4). 

The great English scientist Robert Boyle (1627-1691) was the first to document the use of natural vegetable dyes as acid-base indicators. 

Solimani, R., The flavonols quercetin, rutin and morin in DNA solution UV-vis dichroic (and mid-infrared) analysis explain the possible association between the biopolymer and a nucleophilic vegetable-dye, Biochim. Biophys. Acta, 1336, 281, 1997. 

The processes start with some stone presumably cut to form before coloring. The stone whether mica or so-called crystal, or other stone, is either submitted after cleaning and mordanting to a color bath, whereby color is absorbed into the texture of the stone, or in some cases submitted only to a superficial stain or varnish. It is evident that some of these stains must have been more or less evanescent, depending upon vegetable dyes, while others may have been relatively permanent. It is not to be taken for granted that all the stones used were transparent or colorless before treatment, as many of the precious or semiprecious stones valued by the ancients were not transparent. 

Blue dye is extracted from the leaves of the woad plant (an old world plant). Dyes extracted from plants are called vegetable dyes. People obviously knew how to extract dyes from plants. 

Saffron and turmeric were used to add taste and colour to food. Vegetable dyes were used to make colourful textiles. Red lead was used to add colour to perfume bottles made of clay. Tribal chiefs painted their faces to show their status and to frighten the enemy. 

Henna. Henna is the oldest and most widely used vegetable dye utilized in hair coloring. A temporary chestnut color is produced in blond or auburn hair by applying a paste of henna flowers and leaves ground in hot water immediately before use. (The dye is unstable in aqueous solution.) The addition of indigo achieves darker blue-black shades extracts of walnut shell or logwood enhance brown coloration. 

Halogens can colour / bleach vegetable dyes and kill bacteria. 

Most vegetable dyes are applied to natural animal or plant fibers that have already been spun into yarn or thread. Some, like henna (Lawsonia inermis) are used as dyes for hair, leather, paper, and wood, and may be used as pigments for painting on various materials, including skin. Henna is commonly used for body decorations and temporary henna tattoos. ... 

Bolton, E.M. (1960). Lichens for Vegetable Dyeing. Charles T. Branford Co., Newton Center, MA. 

Lesch, A. (1970). Vegetable Dyeing. Watson-Guptill Publications, New York, NY. 

The study of the dyes, mordants, and other coloring materials used in pre-Columbian textile artifacts remains an inadequately explored area of analytical endeavor. Thin layer chromatography and related techniques should prove productive in the identification of vegetable dyes (7). Inorganic materials can be readily identified by x-ray diffraction methods. 

Earthcycle has developed a line of packaging specific for fresh vegetable and fruit. The packaging trays are water resistant and are available in two colours, natural fibre and vanilla. Other colours are available upon request, using vegetable dyes, so the biodegradability and compostability of the product is not jeopardised. 

Some views do not distinguish between Tyrian and hyacinthine purples, whereas others contend that hyacinthine purple is the vegetable dye indigo. The sources of this confusion are discussed in the following paragraphs. 

Zarda is tobacco leaf broken into smaU pieces and boiled in water with Ume and spices to dryness and then colored with vegetable dyes. It is usuaUy chewed mixed with areca nut and spices. 

Vegetable Dyes rad, blue, yellow, groan 0.67 0.67 9 9. (le suunlne DuPoni Mylar 92A Him... 

The first indicators used were vegetable dyes. Litmus is a familiar example. Most of the indicators that we use in the laboratory today are synthetic compounds that is, they have been made in laboratories by chemists. Phenolphthalein is the most common acid-base indicator. It is colorless in solutions of pH less than 8 ([H3O+] > 10 M) and turns bright pink as pH approaches 10. 

Leechman, J. D., Vegetable Dyes from North American Plants, Saint Paul, The Webb Pub-... 

Mairet, E. M., Vegetable Dyes Being a Book bf Recipes and Other Information Useful to... 

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