Description - Active form of vitamin C that is fat-soluble and more stable but somewhat less potent than L-ascorbic acid when incorporated into products. Used in skincare for its antioxidant properties, helping protect skin from free radical damage, reducing signs of aging, and improving skin texture and evenness.
Benefits - 
Oil-soluble form of vitamin C
Potent antioxidant. Can improve appearance of aged and fragile skin. 
Ascorbyl palmitate can help improve skin texture by promoting collagen synthesis and cell regeneration
Widely used as add-on ingredient in skin-lightening products to correct hyperpigmentation and age spots.
Ascorbyl palmitate can help reduce the appearance of hyperpigmentation and dark spots, leading to a brighter and more even skin tone. 
Antioxidant effect can be increased by combining L-ascorbyl palmitate with L-ascorbic acid and/or vitamin E
Use - 
Add to hot fat phase or emulsifier phase of formulas. If it does not dissolve completely add vitamin C and some oil to a mortar and blend the mixture thoroughly with the pestle. Typical concentration 0.2-3 %. 
Applications - Lotions, creams, sun care & after sun products, shampoos, makeup products.