- A revolutionary weightless conditioner that lets you condition your way to beautiful, healthy looking hair. Powered by our patented Healthy Hair Molecule (OFPMA), Perfect hair Day (PhD) Conditioner is the second step to: helping you wash your hair less often; making hair look healthier instantly and improves over time. Perfect hair Day (PhD) Conditioner is ideal for all hair types. It is silicone-free. Safe and formulated for color and chemically treated hair. After using PhD Shampoo, apply PhD Conditioner to clean, wet hair. Spread evenly throughout hair. Rinse. Style with PhD 5-in-1 Styling Treatment.