Patent ID: 6548468
Filing Date: 2003-04-15
Classification: C09D,C23G

Abstract:
A process for removing from a metal surface:at least 50% of an adherent carbonaceous deposit that is at least 0.2 mm thick and has been formed on at least one of: said metal surface; and paint that is in contact on one side with said metal surface by contact between: at least one of said metal surface and said paint and at least one of: hot gaseous products of combustion emitted from an internal combustion engine; and fuel for, lubricating materials for, or both fuel and lubricating materials for, an internal combustion engine; and any paint that is in contact with said metal surface at the beginning of said process, said process comprising at least one operation of contacting at least one of said metal surface, said paint in contact with said metal surface at the beginning of the process, and said carbonaceous deposit with an aqueous liquid cleaning composition that comprises water and the following components: (A) a component of inorganic alkalinizing agent selected from the group consisting of hydroxides, salts of polyfunctional inorganic acids, and mixtures thereof; and (B) a component of surfactant molecules that are not inorganic alkalinizing agents, at least part of said surfactant molecules being nonionic surfactants; and does not comprise more than about 6% of organic solvent, said operation of contacting being continued for an interval of time and then discontinued and, optionally, being followed by an operation of rinsing said metal surface with pressurized water.