Microcapsules and compositions providing controlled release of actives
View Patent ↗According to the present invention, there are provided microcapsules comprising an emulsion droplet encapsulated by a metallic film, wherein the emulsion droplet comprises an emulsifier disposed around a liquid core material. The present invention also provides processes for preparing the microcapsules, as well as formulations comprising the same. The present invention further provides for certain consumer products comprising: an adjunct material; and a plurality of microcapsules, said microcapsules comprising: an emulsion droplet encapsulated by a metallic film, wherein the emulsion droplet comprises an emulsifier disposed around a liquid core material.
1. A microcapsule comprising an emulsion droplet encapsulated by a metallic film, wherein the emulsion droplet comprises an emulsifier disposed around a liquid core material, wherein the emulsion droplet comprises particles of a first metal selected from palladium, platinum, silver, gold, copper, nickel, tin, and a combination thereof, a second metal selected from silver, gold, nickel, copper, and a combination thereof, the metallic film is formed on said emulsion droplet, and wherein
the liquid core material comprises a volatile material, and the particles of the first metal are nanoparticles,
the density of said particles of the first metal on the emulsion droplet is from 0.0001 g/m 2 to 0.01 g/m 2 of the surface area of the emulsion droplet
the metallic film has:
(i) a maximum thickness of 1000 nm; and
(ii) a minimum thickness of 1 nm;
the emulsifier further comprises a stabilizer stabilizing the nanoparticles; and
the nanoparticles of the first metal are charge-stabilized nanoparticles.
2. A microcapsule according to claim 1 , wherein the emulsifier is cross-linked.
3. A microcapsule according to claim 1 , wherein the microcapsule has a particle size from 0.1 micron to 500 microns.
4. A microcapsule according to claim 1 , further comprising an polymer film at least partially over coating.
5. A process for preparing a microcapsule, the process comprising the steps:
providing an emulsion droplet comprising an emulsifier disposed around a liquid core material; and
forming a metallic film on the emulsion droplet such that the emulsion droplet is encapsulated by the metallic film;
wherein the emulsion droplet comprises particles of a first metal selected from palladium, platinum, silver, gold, copper, nickel, tin, and a combination thereof and the step of forming the metallic film comprises forming a layer of a second metal selected from silver, gold, nickel, copper, and a combination thereof on said particles of the first metal, and wherein
the liquid core material comprises a volatile material, and the particles of the first metal are nanoparticles,
the density of said particles of the first metal on the emulsion droplet is from 0.0001 g/m 2 to 0.01 g/m 2 of the surface area of the emulsion droplet
the metallic film has:
(i) a maximum thickness of 1000 nm; and
(ii) a minimum thickness of 1 nm;
the emulsifier further comprises a stabilizer stabilizing the nanoparticles; and
the nanoparticles of the first metal are charge-stabilized nanoparticles.
6. A consumer product comprising a composition, said composition comprising:
an adjunct material; and
a plurality of microcapsules according to claim 1 .
7. A consumer product according to claim 6 , wherein the liquid core material is selected from the group consisting of perfumes; brighteners; insect repellants; silicones; waxes; flavors; vitamins; fabric softening agents; depilatories; skin care agents; enzymes; probiotics; dye polymer conjugate; dye clay conjugate; perfume delivery system; sensates; anti-bacterial agents; dyes; pigments; bleaches; flavorants; sweeteners; waxes; pharmaceuticals; fertilizers; herbicides and mixtures thereof.
8. A consumer product according to claim 6 , wherein said adjunct ingredient comprises from 0.01% to 99.9% ethanol, by weight of the composition.
9. A microcapsule according to claim 1 , wherein the first metal is selected from palladium, platinum, silver, gold, copper, nickel, tin, and a combination thereof.