Dye

Soluble chemical substance or natural material which can impart color to other materials

A dye is a colored substance that is soluble in some solvent; by contrast pigments are insoluble or nearly so in all solvents. Because of their solubility, dyes can chemically bind to the material they color. Dye is generally applied in an aqueous solution and may require a mordant to improve the fastness of the dye on the fiber.

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