Colour agents

Other ingredients may include cheapening extenders such as castor oil, colouring agents, lubrieants and, rarely, fillers. 

Sweetening, flavouring and colouring agents. Mar of the sugars and other sweetening... 

Cochineal and lac dye can be studied by HPLC with spectrophotometric and NI ESI MS detection. [34] In cochineal, carminic acid appears as a dominant colouring agent. In lac dye extracts, the signal at m/z 536 corresponding to a quasi-molecular ion of laccaic acid A is observed as the dominant one. [19]... 

Ferric oxide prepared for use as an inorganic colouring agent for rubbers. The colour varies according to type, brick-red, orange, bluish-red, etc. 

The red form of mercuric sulphide once popular as an inorganic colouring agent for rubber. Vertical Continuous Vulcanisation... 

An activator in rubber compounds containing organic accelerators. In polychloroprene, zinc oxide is considered to be the accelerator rather than the activator. The use of zinc oxide as a reinforcing agent and as a white colouring agent is obsolescent. Zinc oxide is manufactured by either the French (or indirect) process or by the American (or direct) process. It can be used as a filler to impart high thermal conductivity. 

Zinc chromate, an inorganic colouring agent for rubber. 

It is clear that the colour of a glass is the result of a complex interplay between the co-ordination of the transition metal ions, the redox reactions between the various ions present and the redox potential in the furnace. The traditional archaeological view that colour can be simply related to the presence of various colouring agents can only be regarded as a very crude guide. 

Newton, R.G. (1978). Colouring agents used by Medieval glassmakers. Glass Technology 19 59-60. 

Lycopene, a carotenoid occurring mainly in tomatoes, is extensively applied as a natural colouring agent in food and food products. 

Colouring agent Direct compression (% Z-isomer formed) Wet granulation (% Z-isomer formed)... 

One of the simplest, and hence cheapest smoke colouring agents is an azo dye known as l-(phenylazo)-2-naphthol which is bright orange in colour and also used as a pyrotechnic distress signal. The dye is made by a diazotisation process involving aniline and 2-naphthol as shown in Scheme 10.1. 

Centuries after man had started to use iron oxides as colouring agents, he discovered how to smelt them. The first iron was produced between 4000 and 2000 BC. Since then, this product of iron oxides has been used in weapons, utensils, tools, implements and construction. The extensive English iron ore deposits contributed to the lead England acquired in the Industrial Revolution. 

Prehistoric cave painting of a red horse from Lascaux. The colours used in the painting were obtained from the local deposits of red and yellow ochres, i. e. iron oxides. Similar ochre deposits in Southern France are still mined for pigment production today. As colouring agents, iron oxides have served man more or less continuously for over 30,000 years. A major, modern technological application of these compounds (mainly in synthetic form) is as pigment. 

Many heterocyclic compounds are biosynthesized by plants and animals and are biologically active. Over millions of years these organisms have been under intense evolutionary pressure, and their metabolites may be used to advantage for example, as toxins to ward off predators, or as colouring agents to attract mates or pollinating insects. Some heterocycles are fundamental to life, such as haem derivatives in blood and the... 

Colouring agents— Certain colouring agents (e.g. methylene blue, magenta etc.) are used in mouthwashes for pleasing colour. 

Some Aromatic Amines and Related NItro Compounds—Hair Dyes, Colouring Agents and Miscellaneous Industrial Chemicals 1978 400 pages... 

Carotenoids are found abundantly in plants, and have been used as colouring agents for foods, drinks, confectionery and drugs. The vitamin A group of... 

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