Stability of Vitamin C in cosmetics was studied by formulating as aqueous solution,O/W emulsion and polyalcohol-in-oil emulsion,followed by carrying out of stability test after high temperature accelerating treatment.

All the polyols that can react with TDI and other isocyanates to form polyisocyonate prepolymer,including polyol monomers,castor oil and its alcoholysate and hydroxyl resin,can be classified into the concept of "polyol precursor of prepolymer".

The calculation of L-K-P state equation for multicomponent system;