Cosmetic hand and body moisturizers that are
of value are oil in water emulsions with a high water content,
often more than 60%. Nearly all cosmetic hand creams
contain substances that bind water, particularly
glycerol, sorbitol and propylene glycol, as well
as preservatives. Other important components are
skin protection substances, especially silicone
oils and substances based on them, and hydrophobic
fatty acid esters. These are thought to form a protective
film on the skin after the lipid component has been
penetrated and the water evaporated. Petrolatum, liquid
paraffin and other hydrophobic lipids would be expected
to have a similar effect.
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Specialised skin protection
products can be either water-in-oil or oil-in-water
emulsions. Water-in-oil emulsions can be used to
provide protection against hydrophilic ('water-loving')
irritants, which include soaps and detergents, and
also acids and bases, oil coolants, and so on. They
also show a good skin care effect. Their use does
not involve significant risk of lipid removal from
the skin, because the emulsifiers they contain cannot
emulsify lipids in water. Unfortunately the skin
can feel sticky after their use, and they are not
particularly popular among consumers.
Even such specialised products
cannot completely protect the skin against all irritants,
however.
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