UVA (from 320 nm to 400 nm) and UVB (from 280 nm to 320 nm) have been the focus of sunscreen developers for decades. While these wavelengths allow the human epidermis to tan, they also carry great potential to damage it.
UVB can cause erythema and sunburn while UVA causes a loss of skin elasticity and the appearance of wrinkles, leading to premature aging. It also triggers erythema or amplifies these reactions in some individuals. For these and other reasons, there is constant demand to prevent damage while also controlling the natural tanning process safely.
According to Pierre-Fabre inventors, though, some UV filters are responsible for allergic reactions, i.e., contact eczema, and/or suspected of systemic toxicity, e.g., acting as endocrine disruptors. There is thus a need to develop photoprotective systems that can effectively filter UV while overcoming the disadvantages of intolerance and toxicity.
While researching the optimization of photoprotective systems, these inventors unexpectedly found that the described needs were met using a specific combination of three or four solar filters, described herein.
U.S. Patent 9763867
Publication date: Sep. 19, 2017
Assignee: Pierre Fabre Dermo-Cosmetique
This invention relates to topical, cosmetic or pharmaceutical preparation containing a combination of three or four UV filters comprising:
- One or two UVA filters to obtain a critical wavelength > 370 nm, chosen from:
(i) 5,6,5,6-tetraphenyl-3, 3′-(1,4-phenylene)-bis[1,2,4]triazine;
(iii) Butyl methoxydibenzoylmethane (BMDBM), in a quantity less than 2% w/w; and
(iv) Hexyl-[4-(diethylamino)-2-hydroxybenzoyl]benzoate, -2,4-Bis[4-(2-ethyl-hexyloxy)-2-hydroxyphenyl]-6-(4-methoxyphenyl)-1,3,5-triazine=(BEMT).
- And one or two UVB filters, except for: octocrylene, PABA and ethylhexyl methoxycinnamate.
The composition also contains a pharmaceutically or cosmetically acceptable excipient.