Sunscreen compositions with improved water resistance of UVA sunscreen active agents
Sunscreen compositions, products and methods that include at least one UVA sunscreen active agent, at least one UVB sunscreen active agent, and one or more water insoluble film forming polymers. The compositions, products and methods may further include one or more active or inactive cosmetic ingredients. The water insoluble film forming polymers synergistically affect the UVA and UVB sunscreen active agents, in particularly the UVA sunscreen active agents by significantly enhancing the water resistance of the UVA sunscreen active agents after water exposure as determined by the SPF and UVAPF values measured before and after water exposure.
1. A sunscreen composition comprising
a first phase comprising one or more UVA sunscreen active agents; and
a second phase comprising two or more water insoluble film forming polymers including trimethylsiloxysilicate and methyl dihydroabietate present in an aqueous emulsion, wherein said two or more water insoluble film forming polymers increase water resistance of said one or more UVA sunscreen active agents such that retention of UVAPF values after water exposure, as determined by UVAPF values measured before and after water exposure, is greater than at least 60%.
2. The sunscreen composition of claim 1 , wherein said two or more water insoluble film forming polymers increase water resistance of said one or more UVA sunscreen active agents such that retention of UVAPF values after water exposure, as determined by UVAPF values measured before and after water exposure, is greater than at least 70%.
3. The sunscreen composition of claim 1 , wherein said two or more water insoluble film forming polymers are present in an amount of about 0.5% to about 5.0%, based on the total weight of the sunscreen composition.
4. The sunscreen composition of claim 3 , wherein said two or more water insoluble film forming polymers are present in an amount of about 0.5% to about 2.0%, based on the total weight of the sunscreen composition.
5. The sunscreen composition of claim 1 , wherein the ratio of said trimethylsiloxysilicate to said methyl dihydroabietate is from about 1:4 to about 4:1.
6. A method of absorbing ultraviolet radiation on a keratinous substrate comprising applying a sunscreen composition according to claim 1 to a keratinous substrate and subjecting the keratinous substrate to ultraviolet radiation.