Page 176 - Reliance Foundation School Koparkhairane - School Magazine - Zenith 2020-21
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Dyes make our lives colourful. These are the oldest dyes and are commonly used for dying of
textile and other substances. These are water-soluble dyes and
“Life is like a rainbow. You need both rain and sun to its colour appears.” By unknown. are easy to use. Another example of natural dye is Tyrian
Tina got a new pink colour school bag as a birthday gift. All her friends were excited about her new school purple, which was extracted in very small amounts from the
bag. In school students were having different colour bags and other stationery materials. They were happy glands of a snail, Murex brandaries, indigenous to the
sharing colourful material with each other. Seven colours “VIGBOYR” make our life colourful and happy. Mediterranean Sea. This dye was called 'royal purple' because
Human emotions are also expressed in the form of colours. Nature gives us a variety of colours and shades in it was worn by royals, kings, priests etc
form of flowers, colourful food items, colourful insects etc. They are called natural colours. All above of Lycopene is a common example of natural dye present in tomatoes and other vegetables. This compound is
these is our eyes are please when we see a rainbow in the sky. Nowadays we use colours in form of crayons, responsible for giving red-yellow colour to the substance.
watercolour, acrylic colours, etc. These all are synthetic colours or the colours which are prepared in a
laboratory. These are not obtained from natural sources like plants, leaves or animals. Colours make our life
beautiful.
Colours are organic and inorganic compounds. These are
called dyes. Dyes are chemical substances used for colouring
purposes. Which is your favourite colour? Some of you may say
blue, pink, black, orange etc. Have you ever wondered when
and how these colours are prepared? From when are we started
using colours? History is not my favourite subject and why Synthetic dyes
should I read it? History is not just limited to pre-historic man, Dyes prepared in the laboratory are called synthetic dyes. In 1856, an English chemist William Henry Perkin
copper age, metal age, or just chronological order but here we was involved in the synthesis of antimalarial drugs. Accidentally he discovered 'Mauve' purple colour.
Fig.1: Mixture of all colours
would read about the discovery and development of colours. https://www.pictowall.co.uk/wallpaper-designs/colour/
In this article, we would read about natural and synthetic dyes.
Dyes are organic compounds more commonly
made up of carbon-hydrogen (HC)
combinations. Traditionally dyes obtained from
Fig. 2-The heterocyclic dye
known as indigo is a naturally natural sources like plants, animals etc were
occurring compound that can
used for dying or colouring purposes. Dying
be obtained from plants in the
genus Indigofera. of textile, paper etc is found since ancient
A to Z Botanical Collection/ times. Earlier people use natural dyes, obtain
Encyclopædia Britannica, Inc.
from plant or animal sources. Literature shows
the usage of natural dyes by Egyptians 4000
years ago.
Indigo and Alizarin are the oldest natural dyes. Alizarin is a red dye extracted from the roots of the madder
plant, Rubia tinctorium. Other red dyes were obtained from insects. These include kermes, obtained from Fig.4- Perkin portrait Fig.5- Mauveine in the historical collection of dyes
of the technical University of Dresden
Coccus ilicis (or Kermes ilicis), which infects the Kermes oak, and cochineal, obtained from Dactylopius
coccus, which lives on prickly pear cactus in Mexico. This revolutionised the dye industry. Many attempts were made to synthesise other dyes. These dyes earn
importance because of their properties like stability to high temperature, retaining ability, no action of
acidic substances. Over decades dye industry has expanded to a wide area. It has found applications in a
variety of areas like textile, food, polymer, metallurgy etc.
References:
1) https://www.bbvaopenmind.com/en/science/research/mauve-the-history-of-the-colour-that-
revolutionized-the-world/
2) https://www.britannica.com/technology/dye
3) https://nptel.ac.in/content/storage2/courses/116104046/1.pdf
Fig.3-Structures of Organic dyes
Pratiksha Rajadhakshya
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