Detergent: Definition and Role in Cosmetic Formulation

What Is a Detergent?

A detergent is a substance that assists in removing unwanted materials from a surface, particularly oily or water-insoluble substances. Detergents are generally associated with surfactants, which reduce surface tension and help disperse oils and dirt in water.

When a detergent-containing product is rinsed away, the surfactant system helps carry the removed impurities away with the water.

Detergents in Cosmetic Products

In cosmetics and personal care products, detergents are primarily used for cleansing. They can be found in formulations such as:

• Shampoos
• Shower gels and body washes
• Facial cleansers
• Liquid soaps
• Hand washes
• Other rinse-off cleansing products

Different surfactants can be selected depending on the desired cleansing performance, foam characteristics, mildness and sensory properties of the finished product.

Detergent and Surfactant

The terms detergent and surfactant are closely related but are not completely interchangeable. A surfactant is a broader category of substances that can perform functions such as cleansing, emulsification, solubilisation, wetting and foaming. Detergents are generally surfactant-based systems designed primarily for cleansing.

Detergents in Cosmetic Formulation

The choice and concentration of detergents are important in developing a cleansing product. The formulation needs to provide the required cleansing performance while maintaining the desired skin or hair feel and overall product characteristics.