Question

What is the Dye - What is a dye??

Accepted Answer

A type of colourant  dyes alter the colour of other materials because they selectively absorb different wavelengths of light  The colour a dye produces is determined by the particular wavelength s  of light that are transmitted or reflected by the dye  and not those that are absorbed         Dyes are usually distinguished from pigments in two ways  dyes have an affinity for the substrate to which they are applied  there is an attraction between the two  and they are soluble  they will dissolve in a solvent to form a solution   Most dyes are liquid dyes that have been dissolved in water  or another solvent   although some are made in a paste form  They are either naturally occurring or synthetic organic chemicals  the earliest dyes were made from animals  minerals  and  most predominantly  plants  The first synthetic dyes were produced in the 18th and 19th centuries and quickly replaced natural dyes because they were less expensive  offered a vastly superior range of colours  and could be used to add a variety of important properties to materials  besides a specific colour  such as transparency  purity  and strength of colour         In labelling  dyes are used to colour the face material used to produce coloured labels and as the colourant in some printing inks  where they are absorbed by the fibres in paper face materials and impart a number of important properties including transparency  and purity and strength of colour

Colourant - What is a colourant?

Definition of COLOURANT: