Pigment vs Dye
Pigments and dyes are materials used to color other substances. Both pigments and dyes have been used since time immemorial to color clothes and other substances used by human beings. Pigment is a coloring substance usually in the form of an insoluble powder that makes paint when added to water and oil. A dye is also a coloring material though it is soluble in water and makes a mixture that can be used to color various substances such as clothes, baskets and other material. However, it is difficult to differentiate between the two for most people. This article will highlight their properties to make the differences clear to the readers.
A pigment is a coloring substance that makes the color of product look different because of its absorption of certain wavelengths. There are many substances having this property of selective wavelength absorption though only a few are chosen by humans, to work as colorants. Pigments that produce long lasting results are desired. There are some that produce temporary color change and these pigments are called fugitives. Fugitives fade away with time. Pigments are mostly used to color foods, cosmetics, plastics, paints and inks.
Dyes are substances found naturally and made synthetically too, and having the ability to change the color of the material over which they are applied. Mankind has been aware of dyes since ancient times. In earlier times, most of the dyes were obtained from plant sources. Roots, wood, stem, bark, and leaves of plants were used to provide color that was applied on clothes and other substances, to change their color tone. Indigo and saffron are renowned dyes used by human beings since ancient times. Synthetic dyes were produced for the first time in the 19th century and since then; thousands of synthetic dyes have been produced.
What is the difference between Pigment and Dye?
• Pigment is insoluble, whereas dye is soluble in water.
• There are thousands of dyes including natural and synthetic dyes, whereas pigments are comparatively smaller in number.
• The molecules of dyes are very large in comparison to molecules of pigments which are very small in size.
• Dyes are colorants that work on the principle of selective wavelength absorption while pigments work on principle of light scattering as well as selective absorption of wavelength.
• Dyes are organic in nature whereas pigments are inorganic substances (some of these are highly toxic).
• When used in printing inks, dye based inks make available huge variety whereas pigment based inks have rather limited options.
• Dyes based inks have a shorter life span whereas pigment based inks have a longer life span and are much more durable.