Patent ID: 8519071

Claim:
An aqueous composition having at 20° C. a Brookfield viscosity of 3000 mPas or less (measured at 20° C. with spindle 2 at 20 rpm) and comprising compounds of the general formula (III) R—O-(EO) p X (III) and compounds of the general formula (IV) CH 2 ═CH—CH 2 —O-(EO) q —X (IV) wherein R is an alkyl radical having 8 to 18 C atoms, which may be saturated or unsaturated, straight-chain or branched, X is a sulfate or phosphate group, the sulfate or phosphate group X being in neutralized form, (EO) is an ethylene oxide group, p is a number in the range from 2 to 100, and q is a number in the range from 2 to 100, with the proviso that the aqueous composition comprises the compounds (III) in an amount of at least 35% by weight, based on the overall composition, and with the further proviso that the aqueous composition comprises the sum of the compounds (III) and (IV) in an amount in the range from 35 to 70 percent by weight, based on the overall composition, wherein the composition is prepared by: (i) jointly ethoxylating a mixture of the compounds of the general formula (I) R—O-(EO) n H (I) and compounds of the general formula (II) CH 2 ═CH—CH 2 —O-(EO) m —H (II) wherein R is an alkyl radical having 8 to 18 C atoms, which may be saturated or unsaturated, straight-chain or branched, (EO) is an ethylene oxide group, n is a number in the range from 0 to 30, and m is a number in the range from 0 to 30, with the proviso that the compounds (I) are present in the mixture of the compounds (I) and (II) in a proportion of at least 60% by weight, based on the overall mixture (I) and (II), in such a way that the average degree of ethoxylation of the compounds (I) and (II) is raised by in each case at least two EO units per molecule, to give an intermediate (Z) which represents a mixture of the compounds of the general formula (I*) R—O-(EO) r H (I*) and compounds of the general formula (II*) CH 2 ═—CH—CH 2 —O-(EO) s —H (II*) wherein R is an alkyl radical having 8 to 18 C atoms, which may be saturated or unsaturated, straight-chain or branched, (EO) is an ethylene oxide group, r is a number in the range from 2 to 100, and s is a number in the range from 2 to 100, (ii) and then converting the intermediate (Z) by sulfation or phosphation and subsequent neutralization, into an aqueous composition comprising the compounds (III) and (IV).