Where are W/O Emulsions Useful
Whereas water-in-oil emulsions have enjoyed a
long tradition and a widespread use in Europe,
they have become popular in the United States
only in recent years due to rising popularity in the
sunscreen market. - Why sunscreens? It is well
known that W/O emulsions are more efficient with
a higher SPF (sun protection factor) for the same
percentage of sunscreen. In addition, W/O
emulsions are preferred in sunscreen products
since they are better water-resistant than O/W
emulsions.
W/O emulsions are also often used in makeup
products as this will ensure smooth application
and a great skin feel and also prevent smudging
if volatile solvent are used.
Although most moisturizers (incl. day and night
creams) are O/W emulsions, a W/O emulsion is
preferred if the product is intended for very dry,
sensitive and compromised skin. W/O emulsifiers
are often milder than O/W emulsifiers and do not
disturb the lipid bilayers in the skin. In addition,
they may minimize the trans-epidermal water loss