What is the role of urea in liquid detergent?

Urea in liquid detergent is added to improve solubility, i.e. It is a Hydrotop and act as an emulsifier between the lipophilic surfactant molecules and water (solvent). In the absence of which Phase separation 'll occur and the liquid detergent will separate into surfactant rich top layer and water rich bottom layer, which is bad quality to a common housewife. Yet there are other hydrotrophs replacing Urea these days like Ethanol...

Mohakmel