Satinol Softening Oil From Research Mannikins. Heavy tanning oil. Satinol is a softening oil used to soften all types of tanned capes, hides, and skins. Can be cut with hot water and applied to moist tanned skins prior to finishing the tanning process. Satinol will be absorbed into leather and allows the skin to be much more pliable when dried. Satinol is an all natural product that is safe to use. Does not tan skins.