U.S. Patent No. 7,507,699 B2; Reckitt Benckiser has patented a water-soluble container with a single pocket or single receptacle part that contains a hard surface cleaning composition in powder form. The pocket is sealed by film or closure part which is comprised of at least one cationic surfactant having germicidal properties in which the cationic surfactant is present in an amount of 1-6%; at least one nonionic surfactant (6-20%); an organic acid selected from citric acid, lactic acid, adipic acid, succinic acid, and mixtures thereof, in which the organic acid is present in an amount up to 25%; an alkali salt, selected from carbonates, bicarbonates, sulfates and mixtures (45-90%); and optionally, up to approximately 10% of one or more conventional additives selected from coloring agents, fragrances and fragrance solubilizers, pH adjusting agents and pH buffers including organic and inorganic salts, optical brighteners, opacifying agents, antifoaming agents, enzymes, anti-spotting agents, antioxidants and anti-corrosion agents.
The hard surface cleaning composition in powder form necessarily is comprised of coated citric acid. When the water-soluble container is immersed in water, at least a part of the water-soluble container dissolves releasing the composition which effervesces in water, and wherein the resultant aqueous mixture formed is at a pH of greater than 7.