| abstract |
The invention relates to a novel preparation process for stable complex multiple emulsions of the water-oil-water type, which are highly suitable for use in cosmetic preparations. The primary emulsions of the W/O type are prepared both in the presence of a non-ionic polymeric lipophilic emulsifier and of a non-ionic polymeric stabiliser, which in each case preferably have an HLB in the range from 6 to 10. In a second process step, further water, which contains a hydrophilic emulsifier having a relatively high HLB of preferably 12 to 25, is added to this primary emulsion until phase reversal occurs. It is important that in this second process step the process is not carried out in reverse, i.e. the primary emulsion is not added to the water phase. Further active substances, such as UV filters and vitamins, can be added to the aqueous or oily phase of the emulsions. In a third process step, hydrating agents and/or gelatinising agents can be added and as a result the viscosity can be increased without the stability of the multiple emulsions being impaired. |