Sunscreen Compositions With Natural Waxes For Improved Water Resistance

Abstract

A sunscreen composition having improved water resistance comprising (i) a sunscreen active agent; (ii) a water resistant agent comprising a natural wax having a Damping Factor of less than 1.0 in a linear viscoelastic range at body temperature; and (iii) an emulsifier or a surfactant capable of stabilizing an emulsion of components (i) to (iii), wherein said sunscreen composition maintains at least 75%, preferably at least 85%, and most preferably at least 99%, of its static SPF after water immersion for 4 hours.

What is claimed is: 
     
         1 . A sunscreen composition comprising:
 (i) 0.1 wt. % to 45 wt. % of a sunscreen active agent;   (ii) 0.1 wt. % to 5 wt. % of a water resistant agent comprising a natural wax, wherein said natural wax consists of an animal wax;   (iii) 0.1 wt. % to 10 wt. % of an emulsifier comprising polyglyceryl-3 methylglucose distearate; and   (iv) a humectant, an emollient, or any combination thereof.   
     
     
         2 . The sunscreen composition of  claim 1 , wherein said sunscreen active agent comprises dibenzoylmethane, terephthalylidene dicamphor sulfonic acid, bis-disulizole disodium, disodium phenyl dibenzimidazole tetrasulfonate, diethylamino hydroxybenzoyl hexylbenzoate, bis-diethylamino hydroxybenzoyl benzoate, bis-benzoxazolylphenyl ethylhexylamino triazine, octocrylene, octinoxate, octisalate, homosalate, ensulizole, ethylhexyl triazone, enzacamene, amiloxate, diethylhexyl butamido triazine, benzylidene malonate polysiloxane, padimate-O, trolamine salicylate, cinoxate, p-aminobenzoic acid, oxybenzone, meradimate, titanium dioxide, zinc oxide, bis-octrizole, bemotrizinol, drometrizole trisiloxane, sulisobenzone, dioxybenzone, encapsulated UV filters, or any combination thereof. 
     
     
         3 . The sunscreen composition of  claim 1 , wherein said water resistant agent is present in an amount of 0.1 wt. % to 5 wt. %. 
     
     
         4 . The sunscreen composition of  claim 1 , wherein said animal wax comprises beeswax. 
     
     
         5 . The sunscreen composition of  claim 4 , wherein said animal wax further comprises china wax, shellac wax, or any combination thereof. 
     
     
         6 . The sunscreen composition of  claim 1 , wherein at least one animal wax has a Damping Factor of less than 1.0 calculated using an oscillation amplitude sweep test conducted from 0.01% to 100% strain at a constant angular frequency of 10 Rad/sec and a temperature of 37° C. 
     
     
         7 . The sunscreen composition of  claim 1 , wherein at least one animal wax has a pour point of 30° C. to 65° C. 
     
     
         8 . The sunscreen composition of  claim 1 , wherein said water resistant agent further comprises esters of triacylglycerol, diacylglycerol, and/or monoacylglycerol with fatty acids. 
     
     
         9 . The sunscreen composition of  claim 1 , wherein said emulsifier is present in an amount of 0.1 wt. % to 5 wt. %. 
     
     
         10 . The sunscreen composition of  claim 1 , wherein said emulsifier further comprises comprises glyceryl stearate. 
     
     
         11 . The sunscreen composition of  claim 10 , wherein said emulsifier further comprises sucrose distearate, sorbitan oleate, sorbitan dioleate, polyglyceryl-4 isostearate, polyglyceryl dimerate isostearate, or any combination thereof. 
     
     
         12 . The sunscreen composition of  claim 1 , wherein said humectant comprises glycerin. 
     
     
         13 . The sunscreen composition of  claim 1 , further comprising of 0.5 wt. % to 2.0 wt % of glycerin. 
     
     
         14 . The sunscreen composition of  claim 1 , further comprising a propellant. 
     
     
         15 . The sunscreen composition of  claim 13 , wherein said propellant comprises one or more of isobutene, butane, propane, dimethyl ether, and methyl ether.