According to a new Unilever patent application, organic sunscreen agents have a number of disadvantages. Upon UV exposure, they are known to degrade, sometimes within hours, leaving consumers unprotected.
Further, some organic sunscreens, under certain circumstances, can cause skin irritation or may not be fully compatible with other sunscreen formula components. As such, attempts have been made to stabilize these ingredients; for example, by encapsulation. Encapsulates have shown some advantages but aggressive sunscreen re-application is still required to ensure protection.
Therefore, improvements in chemistry are needed in order to provide consumers with adequate sun protection. This was the focus of the present invention. Here, a polymer of D-glucose along with a branched heteroglycan and other components was unexpectedly shown to improve both SPF and UVA factors.
Compositions for improved sunscreen protection
U.S. Patent Application 20180161263
Publication date: June 14, 2018
Assignee: Conopco, Inc./Unilever
Described in this patent application are topical compositions exhibiting improved sun protection and UVA protection factors over existing sunscreens. The compositions include sunscreen; a polymer of D-glucose and/or a nonionic, branched heteroglycan; and specific diol compounds to enhance skin protection benefits.
In one embodiment, a composition is disclosed comprising: a) 0.1% to 30.0% w/w sunscreen; b) 0.1% to 10.0% w/w C3 to C16 alkane, mono-alkoxy or polyalkoxy diol(s) or a mixture thereof; and c) a cosmetically acceptable carrier. Here, the polysaccharide to alkane/alkoxy diol weight ratio ranges from 70:1 to 1:40, and the alkane diol comprises 1,2-octane diol.
According to the inventors, improvements in SPF and UVA-PF were unexpectedly achieved and further enhanced when alkane diols comprising viscinally substituted hydroxy groups were included in the described compositions. Test results showed compositions made consistent with this invention yielded higher sun protection factors, compared with both a control without saccharide and a comparative saccharide, i.e. hydroxypropyl cellulose.Patent application accessed on June 14, 2018