Vitamin C powder in the fat soluble form. This means that it is added during the oil phase of your cream, lotion, etc. A strong antioxidant, it is used in conjunction with Vitamin A and Vitamin E for a superb preservative affect.
Ascorbic acid is the water (and/or) oil phase of Vitamin C. It less expensive and in my opinion not quite as predictable as a preservative but very effective as an anti-oxidant.
INCI: Ascorbyl Palmitate Suggested Usage Rate: Up to Solubility: Oil Soluble