Stearic acid is the fatty acids from vegetable source is an excellent thickener and emulsion stabilizer for lotions and creams, salves, and body butters. Small amounts (1–4%) in lotions will significantly thicken them. Stearic acid improves the silkiness and glide of emulsions. With stearic acid you can use less wax, which improves skin feel. The more stearic acid, the stiffer and harder the butter. Stearic acid also produces creamier/richer products
INCI
Stearic Acid
BENEFITS
– It is a strong thickener without the weight and tack of waxes; I find it gives a rich buttery feel to products.
HIGH PERFORMANCE INGREDIENT
– Typical Ingredient
– Skin Replenishing
FORMULA LAYER
Functional – Thickener/Gum, Functional – Emulsifier
USAGE RATE
Add to the oil phase
Typical use level 2.0 to 3.0%, up to 25%.
Lower amounts are typically for emulsions, higher amounts are typically for anhydrous products.
Levels above 3.0 will result in soaping (a whitening and lack of absorption when rubbed on the skin)
SOLUBILITY
Oil, Alcohol
TYPE/CHARGE
Anionic, Oil-In-Water
SCENT
None
APPEARANCE
Off white flake or bead
SKIN TYPES
Dry, Mature/Aging
PRODUCTS
Cream/Lotion, Scrub, Balm/Butter
SUBSTITUTION
Cetyl alcohol and cetearyl alcohol
Stearic acid is a stronger thickener/hardener than both cetyl alcohol and cetearyl alcohol, so if either of those are used as an alternative the end product will be softer.
Categories: Functional – Thickener/Gum, Functional – Emulsifier