Liquid detergents are popular with the consumers. Despite numerous liquid detergent products on the market, however, a continuous consumer need exists for improved performance, especially if such can be achieved at a lower cost.
Specifically, consumers look for improved soil removal and improved whiteness and brightness, without having to pay a premium for such benefits. Polyamines, such as tetraethylene pentamine (“TEPA”), are known in petroleum production and refining operations as corrosion inhibitors, demulsifiers, neutralizers, and functional additives.
Laundry applications use modified polyamines. See for instance, WO 00/63334, EP 137 615, U.S. Pat. No. 5,669,984, U.S. Pat. No. 4,664,848, WO 99/49009, U.S. Pat. No. 6,121,226, U.S. Pat. No. 4,622,378, and U.S. Pat. No. 4,597,898. Some of these documents describe aqueous detergent compositions which also incorporate anionic surfactants or fatty acids, or anionic surfactant precursors, in the presence also of strong caustic agents which are added to produce anionic surfactants from anionic surfactant acid precursors or fatty acid salts from fatty acids. The present invention is based at least in part on the discovery that polyanionic ammonium surfactants employed in the present invention exhibit different characteristics and perform substantially better at soil removal than physical mixtures of anionic surfactants/fatty acids and polyamines. Furthermore, in the inventive compositions polyanionic ammonium surfactants can co-exist with a strong inorganic base to offer higher buffering capacity and high wash pH for improved performance.