Abstract
Long lasting performance is very important for make up products. Ideally, the make up color should not change after the application until it is removed. In investigating the causes of make up degradation, we discovered that the wetness of the pigments by secreted sebum from skin is an important factor causing “sebum darkening” which reduces the freshness and attractiveness of the make up.
We attempted to prevent sebum darkening by incorporating spherical silica into the make up formula in order to increase oil absorption. This, however, resulted in only a small improvement. For more substantial improvement, a new approach or new materials were needed. After testing many materials, it was found that titanium dioxide encapsulated in a porous of spherical silica, was the most effective. This process is believed to be due to the unique ability of the encapsulated titanium dioxide to maintain the brightness of the make up even after the silica is wet by sebum and becomes transparent. By using titanium dioxide encapsulated in silica, we have developed a long-lasting make up foundation and solved the sebum darkening problem which has troubled the make up manufacturers for many years.
