Lanolin

LANOLIN is an extremely effective emollient in restoring and maintaining
the all important hydration (moisture balance) of the stratum corneum, and so
prevents drying and chapping of the skin. Equally important, it does not alter
the skin's normal transpiration. Lanolin has been shown to cause the water in
the skin to build up to its normal level of 10-30%, by retarding without
completely inhibiting trans-epidermal moisture loss. Lanolin has the unique
property of absorbing twice its own weight of water. Lanolin has the
physical properties of increasing adhesion to dry skin, and forming protective
films on the skin. Lanolin is compatible with most fats and waxes used in
cosmetics and pharmaceutical preparations. Lanolin is self emulsifying,
producing very stable w/o emulsions with water and is often used in this
hydrous form.