Dye

A dye is a colored substance that chemically bonds to the material to which it is being applied. This distinguishes dyes from <a href="/facts/Pigment/I3clCYkF">pigments</a> which do not chemically bind to the material they color. Dye is generally applied in an <a href="/facts/Aqueous_solution/eRNr3MH2">aqueous solution</a> and may require a <a href="/facts/Mordant/KGkRrkba">mordant</a> to improve the fastness of the dye on the fiber.
The majority of <a href="/facts/Natural_dye/qry80lhk">natural dyes</a> are derived from non-animal sources such as roots, berries, bark, leaves, wood, fungi and <a href="/facts/Lichen/lUrd6Sn7">lichens</a>. However, due to large-scale demand and technological improvements, most dyes used in the modern world are synthetically produced from substances such as petrochemicals. 
Some are extracted from <a href="/facts/Insect/IgDNvnUL">insects</a> and/or <a href="/facts/Mineral/LkUFbNmv">minerals</a>.
Synthetic dyes are produced from various chemicals. The great majority of dyes are obtained in this way because of their superior cost, optical properties (color), and resilience (fastness, mordancy). Both dyes and pigments are colored, because they absorb only some wavelengths of visible <a href="/facts/Light/jeofpMn4">light</a>. Dyes are usually soluble in some solvent, whereas pigments are insoluble. Some dyes can be <a href="/facts/Precipitation_(chemistry)/s3BgsLLY">rendered insoluble</a> with the addition of <a href="/facts/Salt_(chemistry)/lsSKwGpn">salt</a> to produce a <a href="/facts/Lake_pigment/gbfCHHJW">lake pigment</a>.

Dye open-in-new

Dye