ENHANCED PHOTOSTABILITY OF SUNCARE COMPOSITIONS CONTAINING AVOBENZONE
The photostability of avobenzone in a sunscreen composition is stabilized against photodegradation using menthyl anthranilate.
1 . A composition comprising avobenzone and menthyl anthranilate in an amount to stabilize avobenzone against photodegradation.
2 . The composition of claim 1 , wherein menthyl anthranilate is present from about 1 to about 6 weight percent of the composition.
3 . The composition of claim 2 , wherein the composition is substantially free of additional non-sunscreen agents that photostabilize avobenzone.
4 . The composition of claim 1 , wherein menthyl anthranilate is present in an amount of at least 1 weight percent of the composition.
5 . The composition of claim 1 , wherein menthyl anthranilate is present in an amount of at least 3 weight percent of the composition.
6 . The composition of claim 1 , wherein menthyl anthranilate is present in an amount of at least 5 weight percent of the composition.
7 . The composition of claim 1 , wherein the composition further comprises at least one additional sunscreen active besides avobenzone and menthyl anthranilate.
8 . The composition of claim 7 , wherein the additional sunscreen active is selected from the group consisting of octisalate, homosalate, octocrylene, oxybenzone, and combinations thereof.
9 . The composition of claim 1 , wherein the concentration of avobenzone is from about 1 to about 3 weight percent of the composition.
10 . The composition of claim 9 , wherein the concentration of avobenzone is about 2 weight percent of the composition.
11 . The composition of claim 1 , further comprising zinc oxide.
12 . The composition of claim 11 , wherein the concentration of zinc oxide is from about 5 to about 25 weight percent of the composition.
13 . The composition of claim 11 , wherein the concentration of zinc oxide is from about 5 to about 15 weight percent of the composition.
14 . The composition of claim 11 , wherein the concentration of zinc oxide is from about 5 to about 10 weight percent of the composition.
15 . The composition of claim 11 , wherein the concentration of zinc oxide is about 5 weight percent of the composition.
16 . The composition of claim 1 , wherein the composition is in the form of an emulsion.
17 . The composition of claim 16 , wherein the emulsion is an oil-in-water emulsion.
18 . The composition of claim 16 , wherein the emulsion is a water-in-oil emulsion.
19 . A method for protecting the skin against ultraviolet radiation, comprising applying to the skin an effective amount of a composition comprising avobenzone and menthyl anthranilate wherein the menthyl anthranilate is present in a sufficient amount to stabilize the avobenzone against photodegradation.
20 . The method of claim 19 , wherein the concentration of avobenzone in the composition is from about 1 to about 3 weight percent of the composition.
21 . The method of claim 19 , wherein menthyl anthranilate is present from about 1 to about 6 weight percent of the composition.
22 . The method of claim 19 , wherein the composition is substantially free of additional non-sunscreen agents that photostabilize avobenzone.
23 . The method of claim 19 , wherein menthyl anthranilate is present in an amount of at least 1 weight percent of the composition.
24 . The method of claim 19 , wherein menthyl anthranilate is present in an amount of at least 3 weight percent of the composition.
25 . The method of claim 19 , wherein menthyl anthranilate is present in an amount of at least 5 weight percent of the composition.
26 . The method of claim 19 , wherein avobenzone is stabilized against photodegradation for a period of at least 2 hours.
27 . The method of claim 19 , wherein avobenzone is stabilized against photodegradation for a period of at least 4 hours.
28 . A method for improving the photostability of avobenzone in a composition including avobenzone, the method comprising adding menthyl anthranilate to the composition in a sufficient amount to stabilize the avobenzone against photodegradation.
29 . The method of claim 28 , wherein the concentration of avobenzone is from about 1 to about 3 weight percent of the composition.
30 . The method of claim 28 , wherein avobenzone is stabilized against photodegradation for a period of at least 2 hours.
31 . The method of claim 28 , wherein avobenzone is stabilized against photodegradation for a period of at least 4 hours.
32 . The method of claim 28 , wherein the composition is substantially free of additional non-sunscreen agents that photostabilize avobenzone.