Detergent:
Detergents are surface active compounds which get orient at the interface (between water and air) and reduce interfacial tension. It removes dirt from the surface of the textile material by emulsification and suspends the dirt in cleaning liquid.

Classification of Detergent:
Detergents are classified mainly in two- 1. Ionic 2. Non-ionic.
Ionic detergent also divided into three – 1. Anionic 2. Cationic 3. Amphoteric.

1. Anionic Detergent: After being ionized, anion is the dominating ion. For example – Soap. The reaction is-
C17H35CooNa  C17H35Coo- + Na+

C17H35Coo- this portion is very large and dominating ion.

2. Cationic Detergent: After being ionized, cation is the dominating ion. Example- Catyl Pyridinium Chloride.
3. Amphoteric Detergent: Soluble in water and produces both cation & anion. This detergent –a) posses affinity to wool and cellulose fibres. B) Has lubricating properties. C) Behave like anionic in the alkaline solution.
4. Non-ionic Detergent: When dissolved, get oriented at the surface and reduce surface tension. Don’t get ionized and contains hydrophilic head and hydrophobic tail.
Here Hydrophobic means it does not attract the water and the Hydrophillic means it attracts the water