Sodium stearate is primarily used to make soap. This element is the sodium salt derived from stearic acid, and it appears as a white solid in transparent soaps. Sodium stearate is mostly used to create soap bases, but it is also used to produce deodorants, latex paints, rubbers and inks, and to a lesser extent, food additives and flavorings.
Sodium stearate contains hydrophilic (water-absorbing) and hydrophobic (water-repelling) traits. These components are called the carboxylate and long hydrocarbon chains. Despite occurring in the same substance, sodium stearate, these components have dissimilar chemical properties. However, those differences enable the formation of micelles, which help to shape and structure the sodium stearate element. In addition to containing micelles, sodium stearate is formed from several oils and fats.
The percentage of sodium stearate, fats and oils varies among soap type and brand. The soap substance called tallow contains high amounts of stearic acid, which takes the form of triglyceride. In contrast, other soaps have higher fat contents and smaller amounts of sodium stearate.
Sodium stearate, while not considered safe for human consumption, is considered a relatively harmless substance for topical application, and poses little risk of causing adverse health effects such as skin rashes and irritation. According to the Environmental Working Group, sodium stearate is also not suspected to persist or linger in the atmosphere and it biodegrades relatively quickly.