Benzoic acid is a white, crystalline organic compound that is derived from benzoin resin or synthesized from toluene. It is used as a preferred acid in the production of aluminium complex greases, which are widely used in high-temperature applications such as electric motors, compressors, and bearings. Benzoic acid reacts with aluminium hydroxide to form aluminium benzoate, a thickener that provides excellent water resistance, thermal stability, and anti-corrosion properties to the grease.