Solvent Dyes:  These are solvent or oil soluble dyes that may be soluble in  a variety of common solvents such as acetone, toluene, alcohol. MEK, butyl acetate etc.  Many solvent dyes are also soluble in mineral oil, waxes, and lubricants.   Some solvent dyes are therefore useful in coloring candle wax.  Other uses include; dyeing leather, wood staining,  coloring plastics and resins, solvent inks, paints and decorative finishes, and smoke dyes.

Water Soluble Dyes:  These dyes have been modified by adding chemical functional groups to make them more polar and water soluble.  They are very similar in structure to some of the solvent dyes.  Some examples are acid dyes, reactive dyes, and basic dyes.  Many such dyes have ionic chemistry to be able to form bonds with specific substrates such as cotton, wool, or silk.  Water soluble dyes are useful for other things besides textiles.  Some are used for food coloring, water born inks, wood staining, and dyeing of anodized aluminum parts.