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Azo Dyes what are they?

This week we are focusing on EazyColours Colour additives Azo Dyes.

Color has an important role to play in textile, food, printing, pharmaceutical and cosmetic industries.

Azo dyes are considered to be easy to use, relatively cheap and to provide clear, strong colours. There are approximately 2000 azo dyes on the market. They are one of the most widely used chromophores in dye chemistry.

They are known in the industry as nepthol or azoic dyes which mainly consist of brown, red and yellow colours. They are synthetic compounds, formed by azo group which consists of two nitrogen atoms linked with each other. In the primeval times, azotes in French meant nitrogen and that is how the word 'azo' originated.

EazyColours sells a variety of these dyes:


RED 33





Azo dyes are synthetic colours and most of them contain only one azo group. The specialty of this type of dye is that it can provide almost all colors. They are consistent compared to other natural food dyes. They are steady and firm, when compared to the pH series of food. They do not fade when exposed to light and oxygen, and are also heat resistant.

Below are a few examples of the azo dyes EazyColours sells:

Amaranth, also known as FD&C Red No. 2, E123, Red 9, Acid Red 27, or C.I. 16185. Amaranth is an anionic dye. It can be applied to natural and synthetic fibres, leather paper and some resins. As a food additive it is known by its E number, E123. It is a water soluble powder with a red-ish brown to raspberry colour. It can be used in many rinse off cosmetic products such as bathbombs, melt and pour soap, bubble bars ect. In the UK it is mainly used in the food industry namely, giving glace cherries their distinctive colouring conversely amaranth has been banned in the United States since 1976 By the FDA.

Tartrazine (Yellow5) is a synthetic lemon yellow azo dye, primarily used as a food colouring, commonly known to cause possible hyperactivity in children. When used in personal care and cosmetics products it is usually labelled as CI 19140 or FD&C Yellow 5. It too is a water soluble powder. This dye can also be used in almost all rinse off cosmetic produts.

Ponceau 4R in food is known as E Number E124. It is a is a strawberry red azo dye that can be used in a variety of food products. This water soluble colour additive is stable to light & heat, but fades in the presence of ascorbic acid. It too can be used in a wide variety of rinse off cosmetic products. EazyColours sells the granular form which you would disolve in a little water first.

Let us know in the facebook group about any topics you would like us to cover in future. We are here to help and advice you on your journey in the Cosmetic industry. Our customers and those who use our products, are a part of the EazyColours family and we want you to feel included. Don't be shy or sit on the sidelines, no question is too silly please dont feel stupid for asking for help, you won't learn unless you ask :)

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