Polyglycerol fatty acid ester mixture

A bath additive composition comprising:

• 10 to 60 wt-% of a polyglycerol fatty acid ester mixture of mono-, di- and polyesters of a polyglycerol having a degree of polymerization from 2 to 8 and at least one fatty acid selected from group consisting of saturated and unsaturated, branched and unbranched C.sub.6 - to C.sub.14 -fatty acids containing less than 10 wt-% of fatty acids having more than 14 carbon atoms;
• 10 to 60 wt-% of at least one oil or oil-component having cosmetic or therapeutic activity selected from the group consisting of natural and synthetic, mineral, ethereal and fatty animal and vegetable oils, and
• 0 to 70 wt-% water;
• wherein said polyglycerol fatty acid ester mixture has an HLB of greater than 8 and contains
• 0 to 5 parts by weight diglycerol fatty acid esters,
• 20 to 65 parts by weight triglycerol fatty acid esters,
• 20 to 50 parts by weight tetraglycerol fatty acid esters, and
• 5to 40 parts by weight higher polyglycerol fatty acid esters,
• in a total of 100 parts by weight of said ester mixture.

A process for preparing a polyglycerol fatty acid ester mixture of mono-, di- and polyesters of polyglycerols having a degree of polymerization of 2 to 8 and at least one saturated and/or unsaturated fatty acid, said process comprising the steps of initially heating a reaction mixture comprising

• a polyglycerol containing 0 to 5 wt-% diglycerol, 20 to 65 wt-% triglycerol, 20 to 50 wt-% tetraglycerol, and 5 to 40 wt-% higher polyglycerols, and
• at least one fatty acid selected from the group consisting of saturated and unsaturated, branched and unbranched C.sub.6 - to C.sub.14 -fatty acids containing less than 10 wt-% fatty acids having more than 14 carbon atoms, in a molar ratio of polyglycerol to fatty acid of 4:1 to 1:1 and in the presence of at least one catalyst, to a temperature of at least 140.degree. C. and reducing the pressure to at most 600 mbar;
• subsequently heating the reaction mixture in a temperature range from 140.degree. to 220.degree. C. under control of a temperature program, and simultaneously reducing the pressure under control of a pressure program from 600 to 10 mbar;
• removing resulting water of reaction by continuous distillation, and
• upon attaining an acid number of less than 3, cooling the resulting polyglycerol fatty acid ester mixture.