Composition for controlled release of actives
Topical film forming compositions that are able to efficiently deliver active ingredients to keratinic surfaces in a timed release manner comprise a combination of acrylates copolymer and acrylates/VA copolymer, and a combination of propane-1,3 diol and glycerin. The sizes of the pores that develop in the dried film may be controlled or fine tuned.
1. A topical aqueous composition for controlled release of active ingredients comprising:
a film former that comprises acrylates/vinyl acetate copolymer and acrylates copolymer in a weight ratio of 10:1 to 30:1, wherein the weight of the acrylates/vinyl acetate copolymer and acrylates copolymer combined comprise 20%-60% of the weight of the total composition;
a porosity adjuster that comprises propane-1,3 diol and glycerin in a weight ratio of 1:1 to 4:1, wherein the weight of the propane-1,3 diol and glycerin combined comprise 5.5% to 10% by total weight of the composition; and
one or more cosmetically acceptable active ingredients at a total concentration of 0.0001% to 10%, by weight of the composition.
2. The topical aqueous composition according to claim 1 wherein the active ingredient is salicylic acid.
3. The topical aqueous composition according to claim 1 wherein the active ingredient is hyaluronic acid.
4. The topical aqueous composition according to claim 1 wherein the active ingredient is glycolic acid.
5. The topical aqueous composition according to claim 1 wherein the weight ratio of acrylates/vinyl acetate copolymer to acrylates copolymer ranges from 15:1 to 25:1.
6. The topical aqueous composition according to claim 1 wherein the weight ratio of propane-1,3 diol to glycerin ranges from 1:1 to 3:1.
7. The topical aqueous composition according to claim 1 wherein the propane-1,3 diol and glycerin combined comprise 5.5% to 7% by total weight of the composition.
8. A method of making a delivery system for controlled release of active ingredients, the method comprising the steps of:
a) providing a topical aqueous composition according to claim 1 ;
b) applying the composition to a substrate; and
c) allowing the composition to dry to a film, such that pores develop in the film,
wherein the active ingredients accumulate in the pores that develop in the film.
9. The method according to claim 8 wherein the average size of the pores ranges from about 1.5 μm to about 3.0 μm.
10. The method according to claim 8 wherein the average size of the pores ranges from about 0.1 μm to about 1.5 μm.