Patent GB-778901-A (GB)
Title: Improvements relating to emulsions
Inventor: GILBERT ERIC DOUGLAS
IPC: C23G5/06
Filed: 1952-05-15
Abstract: An emulsion comprises a hydrocarbon, a mineral acid, water and two anionic surface-active agents, each of which has the formula RSO3H or RSO4H (R being an alkyl or aryl-alkyl radical) or is a salt of one of these acids and one of which is preferentially soluble in the hydrocarbon and the other in water. The hydrocarbon may be aliphatic, alicyclic or aromatic and may be halogenated; an inhibitor, e.g. thiourea, may be present; the acid may be phosphoric, sulphuric or hydrochloric; the surface active agents may be those known under the Registered Trade Marks "Teepol" and "Petromor."  The hdyrocarbon may be the continuous phase, e.g. in a penetrating oil, but usually water forms the continuous phase.  The emulsion may be formed (1) by pouring a hydrocarbon containing the preferentially hydrocarbon-soluble agent into an acid solution containing the preferentially water-soluble agent, (2) by mixing the hydrocarbon and both surfaceactive agents together with some water, to form an unstable emulsion, and adding the mixture to an acid solution at the place of use, or (3) by forming a stable first emulsion of hydrocarbon, water, some acid and both surface-active agents and adding to an aqueous solution of acid, when inversion will occur. In the latter case, an aromatic solvent or a halogenated hydrocarbon, e.g. solvent naphtha or trichlorethylene, or both is preferably included in the first emulsion when the hydrocarbon is paraffinic. The emulsion may be used for degreasing, pickling or phosphating metals or for cleaning paint.  Specifications 778,903 and 778,904 are referred to.ALSO:An emulsion comprises a hydrocarbon, a mineral acid, water and two anionic surface-active agents, each of which has the formula RSO3H or RSO4H (R being an alkyl or aryl-alkyl radical) or is a salt of one of these acids and one of which is preferentially soluble in the hydrocarbon and the other in water. The hydrocarbon may be aliphatic, alicyclic or aromatic and may be halogenated; an inhibitor e.g. thiourea may be present; the acid may be phosphoric, sulphuric or hydrochloric; the surface active agents may be those known under the Registered Trade Marks "Teepol" and "Petromor".  The hydrocarbon may be the continuous phase e.g. in a penetrating oil but usually water forms the continuous phase.  The emulsion may be formed (1) by pouring a hydrocarbon containing the preferentially hydrocarbon-soluble agent into an acid solution containing the preferentially water-soluble agent, (2) by mixing the hydrocarbon and both surface-active agents together with some water, to form an unstable emulsion and adding the mixture to an acid solution at the place of use, or (3) by forming a stable first emulsion of hydrocarbon, water, some acid and both surface-active agents and adding to an aqueous solution of acid, when inversion will occur. In the latter case, an aromatic solvent or a halogenated hydrocarbon, e.g. solvent naphtha or trichlorethylene, or both is preferably included in the first emulsion when the hydrocarbon is paraffinic. The emulsion may be used for degreasing, pickling or phosphating metals or for cleaning paint.  Specifications 778,903 and 778,904 are referred to