The Application of Rheology in the Development of Cosmetics

Establishing manufacturing processes, skin effects, texture and preventing problems with stability are all integral in the development and manufacture of cosmetics. The aim of this study was to evaluate the usefulness of rheological measurement in these areas of cosmetic production. Rheological measurement was applied at various stages during the development and manufacture of a bath milk, a skin care product, a cleansing milk and a facial cleansing foam. In the case of the bath milk, we applied mainly flow curves to observe the dispersibility of emulsified particles and to predict its stability. Regarding the skin care product, we investigated the rheological properties of materials on its basic formula to understand their effects on its texture. As for the cleansing milk, we used rheological measurements in order to distinguish the physical properties of formulas with defective texture from those that were acceptable. We then compared the rheological properties of an acceptable formula to those that had been produced by different manufacturing methods. The results of the study showed a significant correlation between the rheological measurement results and that of microscopic observations, sensory evaluations and stability tests. In the case of the facial cleansing foam, we selected a manufacturing machine and process with reference to the rheological measurement results. In conclusion, this study proved that rheology is useful in the development and manufacture of cosmetics.