Mordant dyes:

These dyes comprise no natural affinity for the fabric and are applied to it along with the help of specific additional substances termed as mordants. A mordant (Latin mordere = to bite) is any type of substance that can be fixed to fabric and reacts along with the dye to generate colours on fabric. Three sorts of mordants are generally used,

• Acidic mordants similar as tannic acids that are used with basic dyes.
• Basic mordants like albumin or metallic hydroxides that are used with acidic dyes.
• Metallic mordants such as salts of aluminum, chromium, iron, tin, etc., which are utilized with acidic dyes.