Semtol® 70/28 by Sonneborn is a high-purity White Mineral Oil (Liquid Paraffin) of a light viscosity grade. It is refined to an extreme degree to ensure the removal of all aromatic compounds and impurities, meeting the stringent safety requirements for internal and external pharmaceutical use. Semtol 70/28 serves primarily as an emollient, lubricant, and protective vehicle. It softens the skin and prevents transepidermal water loss (TEWL) by forming an occlusive barrier on the stratum corneum. In solid dose manufacturing, it is used to prevent powders from sticking to machinery. In liquid forms, it acts as a laxative. It acts as a non-polar solvent for oil-soluble active pharmaceutical ingredients (APIs) such as fat-soluble vitamins (A, D, E, K). It provides a smooth, non-greasy feel to topical formulations compared to heavier mineral oils. For topical creams and lotions it acts as the oil-phase base for dermatological products treating eczema or dry skin.