Development of novel sun care products is proceeding. These products not only protect the skin from UV rays, but prevent UV damage within the skin.

When the skin is exposed to ultraviolet light, reactive oxygen species and free radicals are generated which damage cells with the resulting production of sunburn cells and injury to DNA. Repeated insults to the skin over a long period may lead to skin cancer.



"Metallothionein" has the function of counteracting reactive oxygen species, but ordinarily it is minimally produced in the skin. Shiseido discovered that metallothionein is formed inside the skin when zinc compounds, utilized as cosmetic raw material, are applied to the skin. This discovery was utilized in the preparation of sun care products.