Alkanolamine soap alkylene oxide condensate and mineral oil compsn. - used for degreasing steel esp. by spraying aq. solution

A compsn. for degreasing steel sheets contains (a) a mixt. of surfactants comprising an alkanolamino soap and an alkylene oxide/hydroxy cpd. condensate and (b) a lesser amt. of oil. A process for degreasing steel sheets comprises spraying the above compsn. on to the steel, particularly as an aq. soln. contg. 15-40% of the above compsn. The process is used for degreasing steel and pressed steel products such as car bodies before phosphate passivation. The compsns. have the advantage of non-inflammability and non-toxicity unlike the solvents at present used. Also, the compsn. does not affect the phosphate treatment; in the event of any delay after the treatment with the compsn., no oxidation occurs. The alkanolamine soap is derived from a 6-18C aliphatic monocarboxylic acid or a mixt. of such acids and a mono di- or tri-alkanolamine. The alkylene oxide condensate is derived from a 6-18C aliphatic alcohol or an (8-12C alkyl)-phenol. The pref. compsn. contains 10-30% (b) and 90-70% (a) with the mixt. (a) contg. 5-25% alkanolamine soap and 85-75% alkylene oxide condensate. Pref. condensates are with 2-12 mols/mol. of ethylene and/or propylene oxides. The oil is a mineral oil low in aromatics, esp. a naphthenic oil. Steel car bodies are sprayed with an aq. compsn. contg. 2.25% of ethanolamine soaps of a mixt. of 8-10C fatty acids; 3.25% naphthalene oil and 10.5% of a nonyl phenol/6 mols. ethylene oxide condensate. The time of spraying is from 1/2 to 2 mins. depending on the production line speed. Any large grease deposits are removed by brushing. After draining, the car bodies are phosphate treated in the normal manner. The car bodies are then painted and the results obtd. are identical to those obtd. when the degreasing is effected using solvent.