Microemulsion-based acid composition and its uses, particularly for cleaning operations
AssigneeSociete Nationale Elf Aquitaine
InventorsJean C. Gautier, Jacques Kamornicki
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Abstract
Composition comprising a hydrophobic liquid, an aqueous acid solution, a surfactant agent and a cosurfactant, a microemulsion being formed between the hydrophobic liquid and the aqueous solution; the surfactant comprises one or more surface-active phosphoric esters. Applications to the cleaning of greasy surfaces, scouring, passivation and phosphatizing, such operation being effected, if desired, in a single step without preliminary degreasing.
Claims18
A microemulsion capable of simultaneously degreasing and scouring a metal substrate comprising, by weight, 18-45% of aqueous acid, 30-65% of liquid hydrocarbon or chlorocarbon, 4-23% of a 4 to 12 carbon atom mono- or dihydric alcohol and 4-28% of one or a mixture of phosphoric acid esters of the formula ##STR5## in which M is selected from the group consisting of hydrogen, sodium, potassium, ammonium, alkaline earth metal and zinc, M' is M or RO[(CH.sub.2).sub.n O].sub.m --, wherein each individual R is phenyl or alkenyl of 1-30 carbon atoms, each individual n is 1-6 and each individual m is 2-15.
A method of simultaneously degreasing and scouring a metal substrate comprising contacting the substrate with a microemulsion, separating the substrate and the microemulsion and rinsing the substrate with water, wherein the microemulsion contains, by weight, 18-45% aqueous acid, 30-65% liquid hydrocarbon or chlorocarbon, 4-23% of a 4 to 12 carbon atom mono- or dihydric alcohol and 4-28% of one or a mixture of phosphoric acid esters of the formula ##STR6## in which M is selected from the group consisting of hydrogen, sodium, potassium, ammonium, alkaline earth metal and zinc, M' is M or RO[(CH.sub.2).sub.n O].sub.m --, each individual R is alkyl or alkenyl of 1-30 carbon atoms, phenyl or alkylphenyl, each individual n is 1-6 and each individual m is 2-15.
Dependencies are inferred from the claim text.