GB704257A - Improvements in detergent compositions - Google Patents

Abstract

A detergent composition comprises (1) between 10 and 20 per cent. by weight of a mixture of anionic detergents containing 50-85 per cent. by weight of an alkyl aryl sulphonate and 50-15 per cent. of an aliphatic amidoalkylene sulphonate of general formula R-CO-NR1-(CH2)n SO3A, where R is an alkyl radical, R1 is hydrogen or an alkyl, aryl or cyclo-aliphatic group, n is from 1 to 5 and A is hydrogen or an alkali metal, and (2) at least 40 per cent. and pre erably 40-65 per cent of alkali metal pyrophosphates and/or tripolyphosphates, the remainder consisting of builders and water. (The term "alkali-metal" includes the ammonium radical.) The alkyl aryl sulphonate may contain a straight or branched chain or a cycloaliphatic group of 6-18 carbon atoms, and the aromatic nucleus may be substituted or unsubstituted and is preferably mononuclear. The detergent may be used as the free sulphonic acid or as the alkali or alkaline earth salt. Preferably this component forms between 5 and 17 per cent. by weight of the total composition. The amidoalkylene sulphonate preferably contains 2 or 3 methylene groups. Suitable alkyl radicals (R) include myristyl, palmityl, oleyl and stearyl. Specified examples of this class of detergent include sodium palmitic tauride, sodium palmitic methyl tauride, sodium myristic methyl tauride, sodium palmitic/stearyl methyl tauride, and sodium palmitic methyl amidopropylene sulphonate. This component preferably forms 30-50 per cent of the active detergent mixture and from 3 to 10 per cent. of the final composition. The commercial grades of aliphatic amidoalkylene sulphonates normally contain about 1- 0 per cent, or more of fatty matter or soap, and the undesirable effect of such impurities may be counteracted by the addition of from 0.1 to about 10 per cent. by weight of the final composition of a compound of formula R-CO-NR1-R11-OH, where R is a saturated or unsaturated group of between 10 and 18 carbon atoms, R1 is hydrogen or an alkyl, aryl or cycloaliphatic group, and R11 is a straight or branched chain alkylene radical having 1 to 5 and preferably not more than 3 carbon atoms or a condensed ethylene oxide radical having not more than 8 and preferably 6 carbon atoms. Suitable compounds include myristic monoethanolamide, palmitic monoethanolamide myristic monoisopropanolamide, palmitic monoisopropanolamide, the mixture of monoethanolamides or monoisopropanolamides derived from coconut- or palm kernel oil fatty acids, and the mixture obtained by condensing 3 mols of ethylene oxide with coconut- or palm kernel oil fatty acid amides. Additional builders such as sulphates, carbonates, chlorides, silicates, borates, meta- or orthophosphates, starch, polyethylene glycol, polyvinyl alcohols and salts of carboxy methyl cellulose may be present. These may be selected such that an aqueous 0.14 per cent. solution of the composition has a pH of 7 or above, preferably from 7 to 10. The compositions may be prepared by blending the ingredients in an aqueous solution or slurry and drying to give flakes or powders. In a typical example a detergent composition is prepared from 10 per cent. of sodium palmitic methyl tauride, 10 per cent. of sodium phenyl polypropylene sulphonate, 55 per cent. tetrasodium pyrophosphate, 5 per cent. sodium silicate, 5 per cent. sodium carbonate, and 15 per cent. of sodium sulphate and water.