| abstract |
O/W emulsions, in particular O/W microemulsions, or O/W/O emulsions or O/W/O′ emulsions comprising at least one emulsifier (emulsifier A) chosen from the group of emulsifiers having the following properties n their lipophilicity either depends on the pH such that the lipophilicity is increased or decreased by raising or lowering the pH, it being unimportant which of the two possible changes in lipophilicity is effected by increasing or lowering the pH, and/or n their lipophilicity depends on the temperature such that the lipophilicity increases with increasing temperature and their hydrophilicity increases with decreasing temperature. |