Stearic Acid

In modern cosmetic formulations, it’s mostly vegetable-derived.

💧 Functions in Formulations

1. Thickener and Hardener

• Used to increase viscosity or stiffen emulsions and balms.
• Common in creams, lotions, and body butters to give a rich, firm texture.

2. Co-emulsifier

• Acts as a stabilizing agent for oil-in-water emulsions.
• Usually combined with emulsifiers.

3. Surfactant (Cleansing Agent)

• In soaps, stearic acid reacts with alkalis (like NaOH or KOH) to form stearates — the actual soap molecules.

4. Opacifier

• Adds opacity and creamy appearance to liquid soaps, lotions, and shampoos.

🧴 Applications
• Creams & Lotions — Thickener, emulsion stabilizer
• Shaving creams — Provides dense, stable foam
• Deodorants — Hardener, texture control
• Lip balms & butters — Adds structure and body
• Candles & soaps — Hardening agent, improves burn stability

⚗️ Typical Use Levels

• Creams/lotions: 1–5%
• Soaps & shaving creams: 5–20%
• Deodorant sticks & balms: 2–10%
• Melt it in the oil phase (above 70 °C) before emulsification.