Dispersing agents are used when solid particles or poorly soluble materials need to be distributed throughout a liquid or semi-solid formulation.

They are particularly important in color cosmetics, mineral sunscreen products, foundations, mascaras, exfoliating products and formulations containing powders.

A good dispersing system promotes wetting of the particle surface and reduces particle-to-particle attraction.

Formulation Considerations

The appropriate dispersant depends on the chemical nature and surface properties of the particle, the continuous phase and the intended formulation.

Poor dispersion can result in sedimentation, agglomeration, color variation, uneven application and changes in texture.

Pigments and mineral particles may require pre-dispersion in an appropriate oil or other carrier before incorporation into the final formulation.

Processing

High-shear mixing or homogenization may be required to achieve a sufficiently fine and uniform dispersion.

However, excessive processing can introduce air, generate heat or affect sensitive ingredients.

References

Barel, A. O., Paye, M. and Maibach, H. I. Handbook of Cosmetic Science and Technology.

Lachman, L., Lieberman, H. A. and Kanig, J. L. The Theory and Practice of Industrial Pharmacy.

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