Living Proof Perfect hair Day (PhD) Dry Shampoo is powered by Living Proof's patented Healthy Hair Molecule (OFPMA) and Triple-Action Cleaning Technology that: absorbs and removes oil, sweat and odor, makes hair look, feel and smell clean, works on all hair colors because it leaves virtually no visible residue or powdery build-up behind, has a time-released fragrance to deliver a light, clean scent throughout the day. Perfect hair Day (PhD) Dry Shampoo is ideal for all hair types. It is silicone-free. Safe and formulated for color and chemically treated hair.