What is Emulsion
An emulsion is a heterogeneous system of two immiscible liquids (water and oil phase), one of which is dispersed as liquid droplets (i.e., the inner or dispersed phase) in the other (i.e., the outer or continuous phase). Water phase could be water or any other hydrophilic liquid i.e., hydrosols and the oil phase could be consisting of any lipophilic substance (or a blend of a few of them) such as oils and butters.
An emulsion is either of water-in-oil (W/O) or oil-in-water type (O/W), depending on the proportion of the outer phase and type of emulsifier used.
– O/W emulsions feel lighter over the skin because the water phase is the outer phase, emulsions are either liquid (lotions and milks) or semi-solids (creams).
– W/O emulsions provide better protection, especially important for mature and dry skin, and night care. They often leave a lubricious, rich, and oily feeling when applied to the skin.
The main difference between the 2 emulsions is the proportion of the liquid phase is higher in O/W emulsions. W/O emulsions have a high oil concentration, whereas O/W emulsions have a low oil concentration.
O/W emulsions tend to be less cost-effective, as oils are always more costly than water and these type of emulsions are generally more challenging to produce.