These two emulsions make up the bases for most creams and lotions on the market, including sun protection products. During the manufacturing process, the ingredients are incorporated in different phases. The most common and most cosmetically elegant emulsion is oil in water This leaves the water phase on the outside when it is rub bin in, giving the product an appealing finish on the skin. Sunscreens that are not designed to be water-resistant are typically formulated with oil in water emulsion bases.
A water in oil emulsion leaves the oily phase on the outside, and since oil is not soluble in water, it creates a 'water resistance.'
Basic water resistance is measured in static water. Over time, the product dissolves away from the skin. The amount of time it takes to fall below the specification for its stated SPF is the time of water resistance. Products that can remain effective in dynamic water for 80 minutes are the peak of the standard.
Tamara's carries PCA's Active Broad Spectrum SPF 45: Water Resistant sunscreen. This is a unique product for many reasons. Although it is a water in oil emulsion, it is light and cosmetically elegant, as well as water-resistant in dynamic water for 80 minutes. Even water-resistant sunscreen should be reapplied every two hours or after vigorously toweling off skin.
