Patent ID: 6916771
Filing Date: 2005-07-12
Classification: C11D

Abstract:
1. A method for clearing restrictions caused by organic materials in drain pipes, comprising: (a) introducing into a drain at least one oxidant-containing liquid which generates foam in situ, the liquid having at least one surfactant, and characterized by a static shear modulus of about 0.5-5 Pa, a relaxation time of about 3-30 sec. and a relative elasticity of about 3-50 sec/Pa, the foam characterized by a density of at least about 0.1 g/ml, a volume of at least two times the liquid volume, a half life of greater than about thirty minutes, wherein the foam contains a cleaning-effective amount of a drain cleaning active, and wherein the foam is characterized by an initial rate of foam development of about 150-800 ml/minute, and an active loss volume of less than about 25 percent; and (b) allowing the composition to remain in contact with the organic restriction material to react therewith.