Gels

What Are Gels?

Gels are dispersed systems, originally liquids or solutions, that are structured to provide a consistency suitable for topical application. Unlike emulsions, gels generally do not contain two immiscible phases with opposite lyophilicity. Depending on the nature of the incorporated substances, they can be hydrophilic hydrogels or lipophilic lipogels (oleogels).

How Are Gels Structured?

The characteristic consistency of a gel is created by gelling or thickening agents, usually polymers, which form a three-dimensional network. Intermolecular forces bind solvent molecules to this network, reducing their mobility and increasing the viscosity of the system.

Properties of Cosmetic Gels

Pure gels are generally transparent, clear, or slightly opalescent. Transparency can be achieved when the ingredients are completely dissolved or present in colloidal form with particles in the submicron range.

Their light texture, appearance, and pleasant sensory characteristics make gels popular in cosmetic care products. They can also be used as a basis for more complex formulations.

Solid particles can be incorporated into gels to create stabilized suspensions, while oily lipids can be incorporated to produce hydrolipid dispersions or quasiemulsions.

References

Handbook of Cosmetic Science and Technology – André O. Barel, Marc Paye, Howard I. Maibach.