| 摘要 |
A metal surface is cleaned (see Group II) by "forcefully" spraying on to it an aqueous alkaline solution containing borax, an alkali metal orthophosphate, and a surface-active agent consisting of a condensation product of nonyl phenol or m-methyl-p-octyl-phenol and ethylene oxide, containing 6-11 ethylene oxide groups per molecule. The concentration of borax (calculated as Na2B4O7.10H2O) is pre ferably 1-5 g/l, the ratio of borax to phosphate (calculated as Na2HPO4) is from 65:35 to 35:65, and the concentration of surface-active agent is 0.01-0.5 g/l. Solid compositions suitable for dissolving in water are disclosed.ALSO:A metal surface is cleaned by "forcefully" spraying on to it an aqueous alkaline solution containing borax, an alkali metal orthophosphate, and a surface-active agent consisting of a condensation product of nonyl phenol or m-methyl-p-octyl phenol and ethylene oxide, containing 6-11 ethylene oxide groups per molecule. Surfaces of e.g. iron, steel, zinc, aluminium and copper, may be cleaned at below 120 DEG F., and then phosphated at 120 DEG F or below using an accelerated phosphating solution, e.g. a zinc phosphate solution containing nitrite, nitrate, sulphite, peroxide, bromate, picric acid or m-nitrobenzene sulphonate and, optionally, sodium ethylene diamine tetraacetate. The phosphate coating may be rinsed in dilute chromic acid solution. |
