13 Jul 2023 --- Japanese cosmetics giant Shiseido has found that the hardening of the stratum corneum, the outermost layer of skin, is a major cause of wrinkle formation. The company has developed a treatment for wrinkles that uses “pure retinol,” a compound that can soften the stratum corneum and prevent wrinkles from forming. As we age, the stratum corneum becomes thicker and harder, while the other layers become softer. This difference in hardness causes wrinkles to form.
