PC 50 (P-1001) Oxidized castor oil Degen Plasticizer Coatings Inks Blown Castor Oils are polymerized by oxidation in order to increase viscosity and specific gravity. Blown Castor is used as a plasticizer in lacquers and inks. Its hydrophobicity makes Blown Castor an excellent water fighter for the printing ink industry. Hydrophobic blown castor oil. Used as a plasticizer in lacquers and inks. Can be used as a very good water fighter for the printing ink industry.