Sunscreen formulation
The present application relates to sunscreen formulations, including foamable sunscreen formulations, that comprise zinc oxide and titanium dioxide particles, suitably in the size range of about 1-100 nm. The compositions suitably produce a minimal residual whitening effect when applied to a skin surface.
1. A sunscreen formulation consisting essentially of:
a. about 1 wt % to about 25 wt % active particles having a primary particle size of about 10 nm to about 500 nm;
b. about 0.1 wt % to about 20 wt % emulsion stabilizer;
c. about 0.01 wt % to about 30 wt % skin conditioner;
d. about 0.01 wt % to about 20 wt % emulsifier; and
e. about 0.05 wt % to about 20 wt % suspending agent,
wherein the formulation produces a minimal residual whitening effect when applied to a skin surface.
2. The sunscreen formulation of claim 1 , wherein the active particles have a primary particle size of about 10 nm to about 200 nm.
3. The sunscreen formulation of claim 1 , wherein the active particles comprise titanium dioxide particles, zinc oxide particles, or both.
4. The sunscreen formulation of claim 1 , wherein the active particles comprise about 1 wt % to about 10 wt % titanium dioxide particles.
5. The sunscreen formulation of claim 1 , wherein the active particles comprise about 1 wt % to about 20 wt % zinc oxide particles.
6. The sunscreen formulation of claim 1 , wherein the active particles comprise about 1 wt % to about 10 wt % titanium dioxide particles and about 1 wt % to about 10 wt % zinc oxide particles.
7. The sunscreen formulation of claim 1 , wherein the emulsion stabilizer is selected from microcrystalline cellulose, cellulose gum, xanthan gum, magnesium aluminum silicate, bentonite clay, hectorite clay, and combination thereof.
8. The sunscreen formulation of claim 1 , wherein the skin conditioner is selected from C 12-15 alkyl benzoate, octyldodecyl neopentanoate, butyl octyl salicylate, caprylyl glycol, glycerin, fatty acid esters of C 8 or greater, mineral oil, and combination thereof.
9. The sunscreen formulation of claim 1 , wherein the emulsifier is selected from glyceryl stearate, ceteareth-20, polysorbate 80, sodium lauryl sulfate, lecithin, and combination thereof.
10. The sunscreen formulation of claim 1 , wherein the suspending agent is selected from polyhydroxystearic acid, sodium polyacrylate polymer, methyl methacrylate crosspolymer, and combination thereof.
11. The sunscreen formulation of claim 1 , further consisting essentially of about 0.01 wt % to about 1 wt % iron oxide particles.
12. The sunscreen formulation of claim 1 , further consisting essentially of a film former.
13. The sunscreen formulation of claim 12 , wherein the film former is selected from polyurethane-2, polymethyl methacrylate, tricontanyl poly(vinyl pyrollidone) (PVP), vinyl pyrollidone/eicosene copolymer, and combination thereof.
14. A sunscreen formulation consisting essentially of:
a. about 1 wt % to about 25 wt % zinc oxide particles having a primary particle size of about 10 nm to about 500 nm; about 1 wt % to about 25 wt % titanium dioxide particles having a primary particle size of about 10 nm to about 500 nm; or a combination thereof;
b. an emulsion stabilizer;
c. a skin conditioner;
d. an emulsifier; and
e. a suspending agent,
wherein the formulation produces a minimal residual whitening effect when applied to a skin surface.
15. The sunscreen formulation of claim 14 , wherein the emulsion stabilizer is selected from microcrystalline cellulose, cellulose gum, xanthan gum, magnesium aluminum silicate, bentonite clay, hectorite clay, and combination thereof.
16. The sunscreen formulation of claim 14 , wherein the skin conditioner is selected from C 12-15 alkyl benzoate, octyldodecyl neopentanoate, butyl octyl salicylate, caprylyl glycol, glycerin, fatty acid esters of C 8 or greater, mineral oil, and combination thereof.
17. The sunscreen formulation of claim 14 , wherein the emulsifier is selected from glyceryl stearate, ceteareth-20, polysorbate 80, sodium lauryl sulfate, lecithin, and combination thereof.
18. The sunscreen formulation of claim 14 , wherein the suspending agent is selected from polyhydroxystearic acid, sodium polyacrylate polymer, methyl methacrylate crosspolymer, and combination thereof.
19. A sunscreen formulation consisting essentially of:
a. about 1 wt % to about 25 wt % zinc oxide particles having a primary particle size of about 10 nm to about 500 nm; about 1 wt % to about 25 wt % titanium dioxide particles having a primary particle size of about 10 nm to about 500 nm; or a combination thereof;
b. about 0.1 wt % to about 20 wt % emulsion stabilizer;
c. about 0.01 wt % to about 30 wt % skin conditioner; and
d. about 0.01 wt % to about 20 wt % emulsifier,
wherein the formulation produces a minimal residual whitening effect when applied to a skin surface.
20. The sunscreen formulation of claim 19 , further consisting essentially of a suspending agent, a film former, or both.