primer

Primer is, quite literally, a product that acts as a foundation layer applied before foundation. Since most products are primarily composed of silicone oil, they create a smooth film on the skin to enhance foundation adhesion and absorb sebum. Depending on the firmness of the silicone oil component, formulations are divided into putty-like types that fill deep pores and lotion-like types that are moisturizing and apply thinly. Because only a small amount of primer is applied, sunscreen must be applied before the primer.