Microcapsules and uses thereof

1. A core-shell microcapsule comprising:

a) a core of an oily phase containing at least one photolabile pro-fragrance ingredient which is a 2-oxoacetate derivative of formula

wherein,

R 1 represents a linear, branched or cyclic, saturated or unsaturated C 1 -C 16 hydrocarbon group, optionally substituted with one or two methoxy groups, and R 2 is a CH(R′)(R″) group derived from the corresponding C 6-20 perfuming aldehyde of formula (R″)CHO or C 6-20 perfuming ketone of formula (R′)(R″)C═O; and

b) a shell surrounding said core and formed by interfacial polymerisation or by a polymerisation induced phase separation process;

wherein the photolabile pro-fragrance ingredient releases a fragrant aldehyde or ketone when exposed to light by transforming the OR 2 moiety into a perfuming aldehyde (R″)CHO or ketone (R′)(R″)C═O, with simultaneous formation of a R 1 COOH or R 1 CHO residue.

2. A microcapsule according to claim 1 , comprising at least one pro-fragrance ingredient of formula (I) wherein R 1 represents a linear, branched or cyclic C 1 -C 10 hydrocarbon group.

3. A microcapsule according to claim 1 , comprising at least one pro-fragrance ingredient of formula (I) wherein R 1 represents a methyl, ethyl, tert-butyl, isopropyl, cyclopentyl or cyclohexyl group or a phenyl group optionally substituted with one or two methoxy groups.

4. A microcapsule according to claim 1 , comprising at least one pro-fragrance ingredient of formula (I) wherein R 2 is derived from an aldehyde selected from the group consisting of benzaldehyde, 1,3-benzodioxol-5-carboxaldehyde, 3-(1,3-benzodioxol-5-yl)-2-methylpropanal, 3-(4-tert-butyl-1-cyclohexen-1-yl)propanal, 2,4-decadienal, 2-decenal, 4-decenal, 8-decenal, 9-decenal, 3-(6,6-dimethyl-bicyclo[3.1.1]hept-2-en-2-yl)propanal, 2,4-dimethyl-3-cyclohexene-1-carbaldehyde, 3,5-dimethyl-3-cyclohexene-1-carbaldehyde, 1-(3,3-dimethyl-1-cyclohexyl)-1-ethanone, 5,9-dimethyl-4,8-decadienal, 3-(3,3- and 1,1-dimethyl-2,3-dihydro-1H-inden-5-yl)propanal, 2,6-dimethyl-5-heptenal, 3,7-dimethyl-2,6-octadienal, 3,7-dimethyloctanal, 3,7-dimethyl-6-octenal, (3,7-dimethyl-6-octenyl)acetaldehyde, 3-dodecenal, 4-dodecenal, 3-ethoxy-4-hydroxybenzaldehyde, 4-ethyl benzaldehyde, 3-(2 and 4-ethylphenyl)-2,2-dimethylpropanal, 2-furancarbaldehyde, 2,4-heptadienal, 3,5,5,6,7,8,8-heptamethyl-5,6,7,8-tetrahydronaphthalene-2-carbaldehyde, 4-heptenal, 2-hexenal, 3-hexenal, 2-hexyl-3-phenyl-2-propenal, 2-hydroxybenzaldehyde, 7-hydroxy-3,7-dimethyloctanal, 4-hydroxy-3-methoxybenzaldehyde, 4- and 3-(4-hydroxy-4-methylpentyl)-3-cyclohexene-1-carbaldehyde, 4-isopropylbenzaldehyde, 8-isopropyl-6-methyl-bicyclo[2.2.2]oct-5-ene-2-carbaldehyde, 3-(4-isopropylphenyl)-2-methylpropanal, 2-(4-isopropylphenyl)propanal, 2- and 4-methoxybenzaldehyde, 6-methoxy-2,6-dimethylheptanal, 3-(2-methoxyphenyl)acrylaldehyde, 8(9)-methoxy-tricyclo[5.2.1,0.(2,6)]decane-3(4)-carbaldehyde, 4-methylbenzaldehyde, 3-(4-methylcyclohex-3-en-1-yl)butanal, 2-(4-methylenecyclohexyl)propanal, 1-methyl-4-(4-methyl-3-pentenyl)-3-cyclohexen-1-carbaldehyde, 3-(4-methyl-3-pentenyl)-3-cyclohexene-1-carbaldehyde, 4-(4-methyl-3-pentenyl)-3-cyclohexene-1-carbaldehyde, (4-methylphenoxy)acetaldehyde, (4-methylphenyl)acetaldehyde, 3-methyl-5-phenylpentanal, 2-(1-methylpropyl)-1-cyclohexanone, 2-methyl-4-(2′,2′,3′-trimethyl-3′-cyclopentenyl)-4-pentenal, 2,4-nonadienal, 2,6-nonadienal, 2-nonenal, 3-nonenal, 6-nonenal, 8-nonenal, 2-octenal, 2-pentyl-3-phenyl-2-propenal, phenoxyacetaldehyde, 2-phenylacetaldehyde, 3-phenylbutanal, 3-phenylpropanal, 2-phenylpropanal, 3-phenyl-2-propenal, 4-(prop-1-en-2-yl)cyclohex-1-enecarbaldehyde, 3-(4-tert-butylphenyl)-2-methylpropanal, 3-(4-tert-butylphenyl)propanal, tricyclo[5.2.1,0(2,6)]decane-4-carbaldehyde, exo-tricyclo[5.2.1,0(2,6)]decane-8exo-carbaldehyde, 2,6,6-trimethyl-bicyclo[3.1.1]heptane-3-carbaldehyde, 2,4,6- and 3,5,6-trimethyl-3-cyclohexene-1-carbaldehyde, 2,2,3-trimethyl-3-cyclopentene-1-acetaldehyde, 2,6,10-trimethyl-2,6,9,11-dodecatetraenal, 2,5,6-trimethyl-4-heptenal, 3,5,5-trimethylhexanal, 2,6,10-trimethyl-9-undecenal, 2-undecenal, 10-undecenal or 9-undecenal and their mixtures, an aldehyde of formula (R″)CHO wherein R″ is a linear or α-branched alkyl group of C 6 to C 15 , and their mixtures.

5. A microcapsule according to claim 1 , comprising at least one pro-fragrance ingredient of formula (I) wherein R 2 is derived from a ketone selected from the group consisting of a damascenone, a damascene, a ionone or methyl ionone, irone, macrocyclic ketone such as, for example, cyclopentadecanone or 3-methyl-4-cyclopentadecen-1-one and 3-methyl-5-cyclopentadecen-1-one or 3-methyl-1-cyclopentadecanone, 1-(2-aminophenyl)-1-ethanone, 1-(3,3-dimethyl-1-cyclohexen-1-yl)-4-penten-1-one, 1-(5,5-dimethyl-1-cyclohexen-1-yl)-4-penten-1-one, 1-(3,3-dimethyl-1-cyclohexyl)-1-ethanone, 2,5-dimethyl-2-octene-6-one, 4,7-dimethyl-6-octene-3-one, (3,7-dimethyl-6-octenyloxy)acetaldehyde, 1-(2,4-dimethylphenyl)-1-ethanone, 4-(1,1-dimethylpropyl)-1-cyclohexanone, 2,4-di-tert-butyl-1-cyclohexanone, ethyl 4-oxopentanoate, 1-(4-ethylphenyl)-1-ethanone, 1-(3,5,5,6,8,8-hexamethyl-5,6,7,8-tetrahydronaphthalen-2-yl)ethanone, 2-hexyl-1-cyclopentanone, 2-hydroxy-3-methyl-2-cyclopenten-1-one, 4-(4-hydroxy-1-phenyl)-2-butanone, 1-(2- and 4-hydroxyphenyl)-1-ethanone, 2-isopropyl-5-methylcyclohexanone, 4-isopropyl-2-cyclohexen-1-one, 1-(5-isopropyl-2-methylcyclohex-1- or 2-en-1-yl)propanone, 1-(4-isopropyl-1-phenyl)-1-ethanone, 2-(2-mercaptopropan-2-yl)-5-methylcyclohexanone, 1-(4-methoxyphenyl)-1-ethanone, 7-methyl-2H,4H-1,5-benzodioxepin-3-one, 5-methyl-3-heptanone, 6-methyl-5-hepten-2-one, methyl 3-oxo-2-pentyl-1-cyclopentaneacetate, 1-(4-methylphenyl)-1-ethanone, 5-methyl-2-(propan-2-ylidene)cyclohexanone, 5-methyl-2-(prop-1-en-2-yl)cyclohexanone, 2-methyl-5-(prop-1-en-2-yl)cyclohex-2-enone, 5-methyl-exo-tricyclo[6.2.1,0(2,7)]undecan-4-one, 3-methyl-4-(1,2,2-trimethylpropyl)-4-penten-2-one, 2-naphthalenyl-1-ethanone, 1-(octahydro-2,3,8,8-tetramethyl-2-naphthalenyl)-1-ethanone, 3,4,5,6,6-pentamethyl-3-hepten-2-one, 2-pentyl-1-cyclopentanone, 4-phenyl-2-butanone, 1-phenyl-1-ethanone, 2- and 4-tert-butyl-1-cyclohexanone, 1-(4-tert-butylphenyl)-1-ethanone), 3,5,6,6-tetramethyl-4-methyleneheptan-2-one, 2,4,4,7-tetramethyl-6-octen-3-one, 1,7,7-trimethyl-bicyclo[2.2.1]heptan-2-one, 2,6,6-trimethyl-1-cycloheptanone, 2,6,6-trimethyl-2-cyclohexene-1,4-dione, 4-(2,6,6-trimethyl-2-cyclohexen-1-yl)-2-butanone, 1-(2,4,4-trimethyl-2-cyclohexen-1-yl)-2-buten-1-one, 1-(3,5,6-trimethyl-3-cyclohexen-1-yl)-1-ethanone, 2,2,5-trimethyl-5-pentyl-1-cyclopentanone or a C 6-15 ketone of formula (R′)(R″)C=o wherein R′ and R″ are linear alkyl groups, and their mixtures.

6. A microcapsule according to claim 1 , comprising at least one pro-fragrance ingredient of formula (I) selected from the group consisting of 3-(4-tert-butyl-1-cyclohexen-1-yl)propyl 2-oxo-2-phenylacetate, 3-(4-tert-butylphenyl)-2-methylpropyl 2-cyclohexyl-2-oxoacetate, 3-(4-(tert-butyl)phenyl)-2-methylpropyl 2-oxo-2-phenylacetate, decyl 2-cyclohexyl-2-oxoacetate, decyl 2-oxo-2-phenylacetate, (2,4-dimethyl-3-cyclohexen-1-yl)methyl 2-cyclohexyl-2-oxoacetate, (2,4-dimethyl-3-cyclohexen-1-yl)methyl 2-oxo-2-phenylacetate, 1-(3,3- and 5,5-dimethyl-1-cyclohexen-1-yl)-4-pentenyl 2-oxo2-phenylacetate, 3-(3,3- and 1,1-dimethyl-2,3-dihydro-1H-inden-5-yl)propyl 2-oxo-2-phenylacetate, 2,6-dimethyl-5-heptenyl 2-oxo-2-phenylacetate, 3,7-dimethyl-2,6-octadienyl 2-cyclohexyl-2-oxoacetate, 3,7-dimethyl-2,6-octadienyl 2-(4-methylcyclohexyl)-2-oxoacetate, 3,7-dimethyl-2,6-octadienyl 3-methyl-2-oxopentanoate, 3,7-dimethyl-2,6-octadienyl 2-oxo-2-phenylacetate, 3,7-dimethyl-2,6-octadienyl 2-oxopropanoate, 3,7-dimethyl-6-octenyl 2-(4-acetylphenyl)-2-oxoacetate, 3,7-dimethyl-6-octenyl(bicyclo[2.2.1]hept-2exo-yl)oxoacetate, 3,7-dimethyl-6-octenyl 2-cyclohexyl-2-oxoacetate, 3,7-dimethyl-6-octenyl 2-cyclopentyl-2-oxoacetate, 3,7-dimethyl-6-octenyl 2-(4-methylcyclohexyl)-2-oxoacetate, 3,7-dimethyl-6-octenyl[4-(2-methyl-1,3-dioxolan-2-yl)phenyl]oxoacetate, 3,7-dimethyl-6-octenyl 3-methyl-2-oxopentadecanoate, 3,7-dimethyl-6-octenyl 3-methyl-2-oxopentanoate, 3,7-dimethyl-6-octenyl 2-oxobutanoate, 3,7-dimethyl-6-octenyl 2-oxohexadecanoate, 3,7-dimethyl-6-octenyl 2-oxopentanoate, 3,7-dimethyl-6-octenyl 2-oxo-2-phenylacetate, 3,7-dimethyl-6-octenyl 2-oxopropanoate, 4-(1,1-dimethylpropyl)-1-cyclohexyl 2-cyclohexyl-2-oxoacetate, 4-dodecenyl 2-oxo-2-phenylacetate, 3,5,5,6,7,8,8-heptamethyl-5,6,7,8-tetrahydronaphthalen-2-yl)methyl 2-oxo-2-phenylacetate, 1-(3,5,5,6,8,8-hexamethyl-5,6,7,8-tetrahydro-2-naphthalenyl)ethyl 2-oxo-2-phenylacetate, 3-hexenyl 2-oxo-2-phenylacetate, 3-hexenyl 2-oxopropanoate, 7-hydroxy-3,7-dimethyloctyl 2-oxo2-phenylacetate, [4- and 3-(4-hydroxy-4-methylpentyl)-3-cyclohexen-1-yl]methyl 2-oxo-2-phenylacetate, 2-isopropyl-5-methylcyclohexyl 2-cyclohexyl-2-oxoacetate, 2-isopropyl-5-methylcyclohexyl 2-oxo-2-phenylacetate, 4-methoxybenzyl 2-cyclohexyl-2-oxoacetate, [4- and 3-(4-methyl-3-pentenyl)-3-cyclohexen-1-yl]methyl 2-oxo-2-phenylacetate, 3-methyl-5-phenylpentyl 2-oxo-2-phenylacetate, 2-methyl-4-(2′,2′,3′-trimethyl-3′-cyclopenten-1′-yl)-4-pentenyl 2-oxo-2-phenylacetate, 2,6-nonadienyl 2-oxo-2-phenylacetate, 3-nonenyl 2-oxo-2-phenylacetate, 2-pentyl-1-cyclopentyl 2-cyclohexyl-2-oxoacetate, 4-phenylbutan-2-yl 2-oxo-2-phenylacetate, 2-phenylethyl 2-oxo-2-phenylacetate, 2-phenylethyl 2-oxopropanoate, 3,5,6,6-tetramethyl-4-methyleneheptan-2-yl 2-oxo-2-phenylacetate, 4-(2,6,6-trimethyl-2-cyclohexenyl)-3-buten-2-yl 2-oxo-2-phenylacetate, 9-undecenyl 2-oxo-2-phenylacetate or 10-undecenyl 2-oxo-2-phenylacetate.

7. A microcapsule according to claim 1 , wherein said microcapsules has an average size of 1 to 200 micrometers.

8. A microcapsule according to claim 1 , wherein said microcapsules has a nominal shell to core mass ratio lower than 20%.

9. A microcapsule slurry consisting of a water-based dispersion or suspension of microcapsules according to claim 1 .

10. A perfuming composition characterized in that it comprises:

a) one or more microcapsules as defined in claim 1 , or a slurry according to claim 9 ;

b) at least one ingredient selected from the group consisting of a perfumery carrier and a perfumery base; and

c) optionally at least one perfumery adjuvant.

11. A consumer product, characterized in that it comprises:

a) as perfuming ingredient, a microcapsule as defined in claim 1 , a slurry according to claim 9 , or a perfuming composition according to claim 10 ; and

b) a consumer product base.

12. A method for intensifying or prolonging the diffusion effect of the characteristic odor of a fragrant aldehyde and/or ketone on a surface, characterized in that said surface is treated with

a) a microcapsule as defined in any one of claims 1 to 8 or a slurry according to claim 9 ;

b) a perfuming composition according to claim 10 ; or

c) a consumer product according to claim 11 ,

under conditions which are susceptible of allowing the release of the fragrant aldehyde and/or ketone.