Maleic anhydride polymer-stabilized microcapsules
The present invention relates to microcapsules with a core-shell or matrix morphology stabilized by cross-linked nanoparticles. A process for the preparation of said microcapsules comprising selecting internal crosslinking of a Pickering emulsion is also an object of the invention. Perfumed consumer products, in particular fine fragrance, home and personal care products are also part of the invention.
1. A particle-stabilized microcapsule obtainable by a process comprising the steps of:
1) suspending inorganic solid particles with at least one amine functionality in water, to form an aqueous phase;
2) suspending at least one maleic anhydride-containing polymer in a perfume or flavor oil to form an oil phase;
3) adding the oil phase to the water phase and mixing the resulting emulsion to form the microcapsule due to reaction between the inorganic solid particles and the maleic anhydride-containing polymer with the resulting cross-linked particles present at the oil/water interface of the emulsion surrounding the perfume or flavor oil.
2. A microcapsule according to claim 1 , wherein the inorganic particles are selected from the group consisting of silica, silicates, titanium dioxide, aluminium oxide, zinc oxide, iron oxide, mica, clays, kaolin, montmorillonite, laponite, bentonite, perlite, dolomite, diatomite, vermiculite, hectorite, gibbsite, illite, kaolinite, aluminosilicates, gypsum, bauxite, magnesite, talc, magnesium carbonate, calcium carbonate, and diatomaceous earth.
3. A microcapsule according to claim 2 , wherein the inorganic particles comprise silica.
4. A particle-stabilized microcapsule obtainable by a process comprising the steps of:
1) suspending inorganic solid particles with at least one amine functionality in water, to form an aqueous phase;
2) suspending at least one maleic anhydride-containing polymer in a perfume or flavor oil to form an oil phase, wherein the at least one maleic anhydride-containing polymer is present in an amount comprised between 0.5 and 50 wt % of the oil phase; and
adding the oil phase to the water phase and mixing the resulting emulsion to form a microcapsule with cross-linked particles present at the oil/water interface.
5. A microcapsule according to claim 4 , wherein the at least one maleic anhydride-containing polymer is present in an amount comprised between 1 and 20 wt % of the oil phase.
6. A microcapsule according to claim 1 , wherein the inorganic particles are present in an amount comprised between 0.1 and 5 wt % of the aqueous phase.
7. A microcapsule according to claim 1 , wherein the size of inorganic, particles is comprised between 10 and 1000 nm.
8. A microcapsule according to claim 1 , wherein the maleic anhydride-containing polymer comprises at least one hydrophobic moiety and at least one maleic anhydride moiety.
9. A microcapsule according to claim 8 , wherein the hydrophobic moiety is selected from the group consisting of styrene, isoprene, ethylene, propylene, methyl vinyl ether, and octadecene.
10. A process for the preparation of a particle-stabilized microcapsule comprising the steps of:
1) suspending inorganic solid particles with at least one amine functionality in water, to form an aqueous phase;
2) suspending at least one maleic anhydride-containing polymer in a perfume oil to form an oil phase;
3) adding the oil phase to the water phase and mixing to form the microcapsule due to reaction between the inorganic solid particles and the maleic anhydride-containing polymer with the resulting cross-linked particles present at the oil/water interface of the emulsion surrounding the perfume or flavor oil.
11. A composition comprising
a) from 10 to 90 wt % of ethanol; and
b) from 0.1 to 15 wt % of microcapsules as defined in claim 1 .
12. A composition according to claim 11 , in the form of a perfume, an eau de toilette, an eau de parfum, a cologne or a body splash or a spray.
13. A liquid perfumed consumer product comprising
a) from 2 to 50% by weight, relative to the total weight of the consumer product, of at least one surfactant;
b) water; and
c) from 0.1 to 15% by weight of microcapsules as defined in claim 1 .
14. A liquid perfumed consumer product according to claim 13 , wherein said product is a home- or personal-care product.
15. A particle-stabilized microcapsule comprising
a) a core of hydrophobic perfume or flavor; and
b) a shell consisting of inorganic particles selectively cross-linked with a maleic anhydride-containing polymer.
16. A particle-stabilized microcapsule according to claim 1 , wherein the cross-linked particles form a matrix structure.
17. The microcapsule of claim 1 , which is stable in an amount of from 0.1 to 15 wt % in a composition comprising from 10 to 90 wt % ethanol and the microcapsules.
18. The microcapsule of claim 17 , wherein the composition is in the form of a perfume, an eau de toilette, an eau de parfum, a cologne or a body splash or a spray.
19. The microcapsule of claim 1 , which is stable in an amount of from 0.1 to 15 wt % in a composition comprising from 2 to 50 wt % of at least one surfactant, water and the microcapsules.
20. The microcapsule of claim 19 , wherein the composition is in the form of a home- or personal-care product.