HYBRID MICROCAPSULE

Abstract

The present invention relates to hybrid microcapsules, with a core based on a hydrophobic material, preferably a perfume, and a polymeric shell comprising chitosan particles. The process for preparing the microcapsules is also an object of the invention. The perfume compositions and the consumer products comprising the capsules, in particular perfumed consumer products in the form of household or personal care products, are also part of the invention.

Description

HYBRID MICROCAPSULES Field of Invention The present invention relates to hybrid microcapsules, with a core based on a hydrophobic material, preferably a perfume, and a polymeric shell comprising chitosan particles. The process for preparing the microcapsules is also an object of the invention. The perfume compositions and consumer products comprising the capsules, in particular perfumed consumer products in the form of home care or personal care products, are also part of the invention. Background of the Invention One of the challenges facing the perfume industry lies in the relatively rapid loss of the olfactory benefit provided by odoriferous compounds due to their volatility, particularly that of the top notes. To adjust the release rates of volatile compounds, delivery systems, such as microcapsules containing a perfume, are needed to protect and then release the core payload upon activation. A key industry requirement for these systems is their ability to survive suspension in challenging bases without dissociating or physically degrading. By i? / conn / zznz / E / YiAi Ref. 332319 For example, perfumed personal and household cleaners containing high levels of aggressive surfactant detergents pose a major challenge to the stability of microcapsules. Aminoplast microcapsules, formed from a melamine-formaldehyde resin, have been widely used to encapsulate hydrophobic active ingredients, thereby protecting them and providing controlled release. However, capsules, such as those made of aminoplast, suffer from stability problems when used in consumer products containing surfactants, such as perfumes, especially after prolonged storage at elevated temperatures. In such products, even if the capsule wall remains intact, the encapsulated active ingredient tends to leak from the capsule by diffusion through the wall due to the presence of surfactants that can solubilize the encapsulated active ingredient in the product's base. This leakage phenomenon reduces the capsules' effectiveness in protecting the active ingredient and providing controlled release. A variety of strategies have been described to improve the stability of oil-core microcapsules. Crosslinking the capsule walls with chemical groups, such as poly(amines) and poly(isocyanates), has been described as a way to improve microcapsule stability. For example, WO2011 / 154893 describes a process for preparing polyurea microcapsules using a combination of aromatic and aliphatic polyisocyanates at specific relative concentrations. The stabilization of oil / water interfaces with inorganic particles has been described in so-called Pickering emulsions. In this context, the functionalization of inorganic particles to enable crosslinking is known. For example, Pickering emulsions crosslinked from an external aqueous phase with polyelectrolytes that provide electrostatic interactions have been described previously (Li Jian et al. in Langmuir (2010), 26(19), 15554-15560). However, such systems are very likely to dissociate in a surfactant base or in ethanol over time, as the electrostatic interactions are insufficient to promote stability. Covalent crosslinking in relation to Pickering emulsions has also been described in the preparation of collodosomas. In particular, the use of diisocyanates as crosslinking agents has been described in scientific publications.WO2009 / 063257 also describes the use of polyisocyanates as potential crosslinking agents for surface-modified inorganic particles to prepare microcapsules with a higher level of UV protection for their contents. These products are typically proposed for agrochemical applications. This type of system is not suitable for encapsulating perfumes. In fact, to maintain good morphology and permeability of the microcapsules, an excess of surface-modified inorganic particles is required. Another problem is that these microcapsules offer little room for size adjustment. Furthermore, the amount of particles adsorbed at the oil-water interface is limited, which affects the properties of the capsule membranes. Therefore, there is still a need to provide new microcapsules without compromising their performance, particularly in terms of stability in a consumer product, as well as in supplying good performance in terms of supplying hydrophobic material. Brief Description of the Invention Therefore, a first aspect of the invention is a core-shell microcapsule comprising: a) an oil-based core comprising a hydrophobic material, preferably a perfume oil; and b) a polymeric coating comprising chitosan particles. A second aspect of the invention is a core-shell microcapsule suspension comprising at least one microcapsule made of: cann / zznz / E / YiAi a) an oil-based core comprising a hydrophobic material, preferably a perfume oil; and b) a polymeric coating comprising chitosan particles. A third aspect of the invention is a process for preparing core-shell microcapsules or a suspension of core-shell microcapsules as defined above, wherein the process comprises the steps of: 1) suspend chitosan particles in water to form an aqueous phase; 2) prepare an oily phase comprising a hydrophobic material, preferably a perfume oil; 3) Add the oily phase to the aqueous phase and mix them to form a Pickering oil-in-water emulsion, under conditions that allow the formation of core-shell microcapsules by means of interfacial polymerization and / or interfacial reaction, wherein a polyfunctional monomer is added in step 1) in the aqueous phase and / or in step 2) in the oily phase. In a fourth aspect, the invention relates to a microcapsule that can be obtained by means of such a process, as well as to the perfume compositions and consumer products containing them. In a final aspect, the invention relates to the use i? / conn / zznz / E / YiAi of chitosan-based particles, for the stabilization of a Pickering emulsion further subjected to an interfacial polymerization reaction. Brief Description of the Figures Figure 1: is a schematic representation of the formation of a Pickering emulsion when chitosan particles are used to stabilize the oil phase. Detailed Description of the Invention Unless otherwise stated, percentages (%) refer to the percentage by weight of a composition. An active ingredient is understood to be a single compound or a combination of ingredients. Perfume or flavoring oil means a single perfume or flavoring compound or a mixture of several perfume or flavoring compounds. A consumer product or final product is understood to be a manufactured product ready to be distributed, sold and used by a consumer. A microcapsule, or similar, in the present invention has a morphology that can vary from a core-shell type to a matrix type. According to one embodiment, it is of the core-shell type. In this case, the microcapsules comprise a core based on a hydrophobic material, typically a perfume, and a shell comprising chitosan particles. The microcapsules have a particle size distribution in the micrometer range (e.g., a mean diameter) between approximately 1 and 3000 micrometers, preferably between 1 and 1000 micrometers, more preferably between 1 and 500 micrometers, and even more preferably between 5 and 50 micrometers. The polymeric shell of the microcapsule according to the present invention is formed by means of interfacial polymerization and / or interfacial reaction in the presence of chitosan particles. Particle size is understood to be an average particle diameter based on the size distribution measured by dynamic light scattering (DLS) using the Zetasizer Nano ZS equipment from Malvern Instruments Ltd., UK, when the particles are dispersed in an aqueous phase. Microcapsule size means the volume mean diameter (D[4,3]) of the relevant capsules, the capsule suspension obtained by laser light scattering of a diluted sample in a Malvern Mastersizer 3000 apparatus. A polyfunctional monomer is understood to be a molecule that, as a unit, reacts or chemically bonds to form a polymer or a supramolecular polymer. The polyfunctional monomer is either oil-soluble or water-soluble. The polyfunctional monomer of the invention has at least two functional groups that have the ability to react with or bond to the functional groups of another component (e.g., chitosan particles) and / or that have the ability to polymerize to form a polymeric shell. The terms shell and wall are used interchangeably in the present invention. By polyurea-based wall or coating, it is understood that the polymeric coating comprises urea linkages produced either by an amino functional crosslinker or by hydrolysis of isocyanate groups to produce amino groups that have the ability to further react with isocyanate groups during interfacial polymerization. Surprisingly, it has now been discovered that core-shell microcapsules can be obtained that encapsulate the hydrophobic material when chitosan particles are contained within the shell. Therefore, the microcapsules of the invention provide a solution to the aforementioned problems because they improve storage stability on challenging substrates, even with a low concentration of polymeric material in the shell, and because they enhance application performance due to the cationic surface charges of the chitosan particles within the microcapsules. CORE-SHAPED MICROCAPSULE A first object of the invention is a core-shell microcapsule i? / cann / zznz / E / YiAi comprising: a) an oil-based core comprising a hydrophobic material, preferably a perfume oil; and b) a polymeric coating comprising chitosan particles. Hydrophobic material The hydrophobic material according to the invention can be an inert material, such as solvents or active ingredients. When hydrophobic materials are active ingredients, they are preferably chosen from the group consisting of flavors, flavoring ingredients, perfumes, perfume ingredients, nutraceuticals, cosmetics, pest control agents, biocidal active ingredients, and mixtures thereof. According to a particular modality, the hydrophobic material comprises a mixture of a perfume with another ingredient selected from the group consisting of nutraceuticals, cosmetics, pest control agents, and biocidal active ingredients. According to a particular modality, the hydrophobic material comprises a mixture of biocidal active ingredients with another ingredient selected from the group consisting of perfumes, nutraceuticals, cosmetics, pest control agents. i? / conn / zznz / E / YiAi According to a particular modality, the hydrophobic material comprises a mixture of pest control agents with another ingredient selected from the group consisting of perfumes, nutraceuticals, cosmetics, and biocidal active ingredients. According to a particular modality, the hydrophobic material comprises a perfume. According to one particular modality, the hydrophobic material consists of a perfume. According to a particular modality, the hydrophobic material consists of biocidal active ingredients. According to a particular modality, the hydrophobic material consists of pest control agents. Perfume (or perfume oil) here refers to an ingredient or composition that is a liquid at approximately 20°C. According to either of the above definitions, perfume oil may be a single fragrance ingredient or a mixture of ingredients forming a fragrance composition. A fragrance ingredient here refers to a compound used primarily to impart or modulate an odor. In other words, for such an ingredient to be considered a fragrance, it must be recognized by a person skilled in the art as having the ability to impart or modify, in a positive or pleasant manner, the odor of a composition, and not merely as having an odor.For the purposes of the present invention, the perfume oil also includes a combination of perfume ingredients with substances that jointly improve, enhance, or modify the delivery of the perfume ingredients, such as perfume precursors, emulsions, or dispersions, as well as combinations that impart an additional benefit beyond modifying or imparting an odor, such as long duration, increased odor perception, neutralization of bad odor, antimicrobial effect, microbial stability, pest control. The nature and type of the fragrance ingredients present in the oil phase do not warrant a more detailed description here, which in any case would not be exhaustive. A person skilled in the technique is able to select them based on their general knowledge and according to the intended use or application and the desired organoleptic effect. Generally speaking, these fragrance co-ingredients belong to chemical classes as varied as alcohols, aldehydes, ketones, esters, ethers, acetates, nitriles, terpenoids, nitrogenous or sulfurous heterocyclic compounds, and essential oils, and the fragrance co-ingredients can be of natural or synthetic origin. Many of these co-ingredients are listed in reference texts such as S.'s book. i? / conn / zznz / E / YiAi Arctander, Perfume and Flavour Chemicals, 1969, Montclair, New Jersey, USA, or its more recent versions, or in other works of a similar nature, as well as in the abundant patent literature in the field of perfumery. In particular, one can cite perfumery ingredients that are commonly used in perfume formulations, such as: - Aldehydic ingredients: decanal, dodecanal, 2-methyl-undecanal, 10-undecenal, octanal, nonanal and / or nonenal; Herbal ingredients: eucalyptus oil, camphor, eucalyptol, 5methyltricyclo[6.2.1.0~2.7~]undecane-4-one, l-methoxy-3hexanethiol, 2-ethyl-4,4-dimethyl-l,3-oxathane, 2,2,7 / 8,9 / 10tetramethylspiro[5,5]undec-8-en-l-one, menthol and / or alpha-pinene; - Balsamic ingredients: coumarin, ethyl vanillin and / or vanillin; - Citrus ingredients: dihydromyrcenol, citral, orange oil, linalyl acetate, citronellin nitrile, orange terpenes, limonene, lp-menthen-8-yl acetate and / or 1,4(8)-p-mentadiene; - Floral ingredients: methyl dihydrojasmonate, linalool, citronelol, phenylethanol, 3-(4-terc-butylphenyl)-2methylpropanal, hexylcinnamic aldehyde, benzyl acetate, benzyl salicylate, tetrahydro-2-isobutyl-4-4-methyl, pyranol(2) 2-(methylamino)methyl benzoate, (E)-3- i? / cann / zznz / E / YiAi methyl-4-(2,6,6-trimethyl-2-cyclohexen-l-yl)-3-butene-2-one, (1E)-1- (2,6,6-trimethyl-2-cyclohexen-l-yl)-l-penten-3-one, 1(2,6,6-trimethyl-l,3-cyclohexadiene-l-yl)-2-buten-l-one, (2E)1-(2,6,6-trimethyl-2-cyclohexen-l-2-bul-one, (2E)-1[2,6,6-trimethyl-3-cyclohexen-l-yl]-2-butene-l-one, (2E)-1(2,6,6-trimethyl-l-ciclohexen-l-yl)-2-butene-l-one, 2,5dimethyl-2-indanmethanol, 2,6,6-trimethyl-3-cyclohexenol-lcarboxylate, 3- (4,4-dimethyl-l-cyclohexen-l-yl)propanal, hexyl salicylate, 3,7-dimethyl-l,6-nonadiene-3-ol, 3-(4isopropylphenyl-2-propanel, dehydrogenase geraniol, p-menth-l-en-8-ol, 4-(1,1-dimethylethyl)-1cyclohexyl acetate, 1,l-dimethyl-2-phenylethyl acetate,4ciclohexil-2-metil-2-butanol, salicilato de amyl, dihidrojasmonato de metilo alto en cis, 3-metil-5-fenil-1pentanol, propionato de verdilo, acetato de geranilo, tetrahidro linalool, cis-7-p-mentanol, (S)-2-(l,ldimetilpropoxi)propanoato de propilo, 2-metoxinaftaleno, acetato de 2,2,2-tricloro-l-feniletilo, 4 / 3-(4-hidroxi-4metilpentil)-3-ciclohexeno-l-carbaldehido, aldehido amilcinámico, 8-decen-5-ólido, 4-fenil-2-butanona, acetato de isononilo, acetato de 4-(1,1-dimethylethyl)-1-cyclohexylo, verdigris isobutyrate and / or mixture of methylionone isomers;, - Fruit ingredients: gamma-undecalactone, 2,2,5- trimethyl-5-pentylcyclopentanone, 2-methyl-4-propyl-l,3oxathiane, 4-decanolide, 2-ethyl-pentanoate, cann / zznz acetate de-hemethylYiAi2 gamma-nonalactone, allyl heptanoate, 2-phenoxyethyl isobutyrate, 2-methyl1,3-dioxolane-2-ethyl acetate, 3-(3,3 / 1,l-dimethyl-5indanyl)propanal, 1,4-cyclohexanodicarboxyl acetate diet 3-methyl-2-hexen-l-yl, [3-ethyl-2-oxiranyl]acetate of 1-[3,3-dimethylcyclohexyl]ethyl and / or diethyl 1,4-cyclohexane dicarboxylate; - Green Ingredients: 2-methyl-3-hexanone (E)-oxime, 2,4-dimethyl-3-cyclohexene-l-carbaldehyde, 2-tercbutyl-l-cyclohexyl acetate, styralyl acetate, (2methylbutoxy)ol-4demethyl ether-allyl-acetate, 3-methylbutoxy diphenyl, (Z)-3-hexen-l-ol and / or 1-(5,5-dimethyl-l-cyclohexen1-yl)-4-penten-l-ona; Musk ingredients: 1,4-dioxa-5,17cycloheptadecanedione, (Z)-4-cyclopentadecen-l-one, 3-methylcyclopentadecanone, l-oxa-12-cyclohexadecen-2-one, 1-oxa-13-cyclohexadecen-2-one, (9Z)-9-cycloheptadecen-l-one, 2-{IS)-1-[(IR)-3,3-dimethylcyclohexyl]ethoxy}-2-oxoethyl propionate, 3-methyl-5-cyclopentadecen-l-one, 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-g-2-benzopyran, (IS,1'R)-2-[1-(3',3'-dimethyl-1'cyclohexyl)ethoxy]-2-methylpropyl propanoate, oxcyclohexadecan-2-one and / or (IS,1'R)-[1-(3',3'-dimethyl-1'cyclohexyl)ethoxycarbonyl]methyl propanoate; Wood ingredients: 1-[ (1RS,6SR)-2,2,6 i? / conn / zznz / E / YiAi trimethylcyclohexyl]-3-hexanol, 3,3-dimethyl-5-[(IR)-2,2,3trimethyl-3-cyclopentene-l-yl-penten]-2-4-dimethenol, 3,4'o [oxirane-2 , 9'-triccyclo[6.2.1.02'7] undec [ 4 ] eno, (1-ethoxyethoxy)cyclododecane, 2,2,9,11tetramethylspiro[5,5]undec-8-en-l-yl acetate, 1- (octahydro-2,3,8,8tetramethyl-2-naphthalenyl)-1-ethanone, patchouli oil, patchouli oil terpene fractions, clearwood®, (l'R,E)-2-ethyl-4-(2',2',3'-trimethyl-3'-cyclopentenyl-1,2' 2-ethyl-4- (2,2,3-trimethyl-3-cyclopenten-yl)-2buten-l-ol, methyl cedryl cebona, 5-(2,2,3-trimethyl-3cyclopentenyl)-3-methylpentane-2-ol, 1-(2,3,8,8-tetramethyl1,2,3,4,6,7,8,8a-octahydronaphthalene-2-yl)ethane-l-one and / or isobornyl acetate; - Other ingredients (for example, amber, especial in powder or acuoso): dodecahidro-3a,6,6,9a-tetramethylnafto[2,1-b]furano and any of its esteroisomers, heliotropina, aldehyde anisico, euqenol, aldehyde cinnamic, aceite de clove, 3-(1,3-benzodioxol-5-il)-2-methylpropanal, 7-metil-2H-l,5-benzodioxepin-3(4H)-ona,2,5,5-trimetil- 1,2,3,4,4a,5,6,7-octahidro-2-naftalenol, acetato de 1fenilvinilo, 6-metil-7-oxa-l-tia-4-azaespiro[4.4]nonano y / o 3(3-isopropil-l-fenil)butanal. It should also be understood that the ingredients can also be compounds that are known to release in a controlled manner different types of perfume compounds also known as perfumes or perfumes. The non-limiting examples of suitable proper fumes may include 4(dodecylthio)-4-(2,6,6-trimethyl-2-cyclohexen-l-yl)-2-butanone, 4-(dodecylthio)-4-(2,6,6-trimethyl-l-cyclohexen-l-yl)-2butanone, trans-3-(dodecylthio)-1-(2,6,6-trimethyl-3cyclohexen-l-yl)-1-butanone, oxo(phenyl)acetate de 2phenylethyl, oxo(phenyl)acetate de 3,7-dimethylocta-2,6-dien-yl, oxo(phenyl)acetate de (Z)-hex-3-en-l-yl, hexadecanoate de 3,7-Dimethyl-2,6-octadien-l-yl, bis(3,7dimethylocta-2,6-dien-l-yl) succinate, (2-((2-methylundec-l-en-lyl)oxy)ethyl)bencene, l-methoxy-4-(3-methyl-4-phenetoxybut-3-en-l-yl)bencene, (3-methyl-4-phenetoxybut-3-en-l-yl)bencene, 1( ( (Z)-hex-3-en-l-yl)oxy)-2-methylundec-l-eno, (2- ( (2methylundec-l-en-l-yl)oxy)ethoxy)bencene, 2-methyl-l-(octan-3yloxy)undec-l-eno,l-methoxy-4-(l-phenethoxyprop-l-en-2yl)benzene, l-methyl-4-(l-phenethoxyprop-l-en-2-yl)benzene, 2(1 —phenethoxyprop-l-en-2-yl)naphthalene, (2phenethoxyvinyl)benzene, (1-((3,7-dimethyloct-6-en-lyl)oxy)prop-l-en-2-yl)naphthalene or a mixture thereof., The fragrance ingredients may be dissolved in a solvent currently used in the perfume industry. The solvent is preferably not an alcohol. Examples of such solvents include diethyl phthalate, isopropyl myristate, Abalyn® (rosin resins, available from Eastman), benzyl benzoate, ethyl citrate, limonene, other terpenes, or isoparaffins. Preferably, the solvent is highly hydrophobic and spherically hindered, such as Abalyn® or benzyl benzoate. Preferably, the perfume comprises less than 30% solvent. More preferably, the perfume comprises less than 20%, and even more preferably, less than 10% solvent; all these percentages are defined by weight relative to the total weight of the perfume. Even more preferably, the perfume is essentially solvent-free. The preferred fragrance ingredients are those with high spherical hindrance, and in particular those from one of the following groups: - Group 1: perfume ingredients comprising a cyclohexane, cyclohexene, cyclohexanone or cyclohexenone ring substituted with at least one linear or branched C1 to C4 alkyl or alkenyl substituent; - Group 2: perfume ingredients comprising a cyclopentane, cyclopentene, cyclopentanone or cyclopentenone ring substituted with at least one linear or branched C4 to Cs alkyl or alkenyl substituent; - Group 3: Perfume ingredients comprising a phenyl ring or perfume ingredients comprising a cyclohexane, cyclohexene, cyclohexanone or cyclohexenone ring substituted with at least one linear or branched C5 to C5 alkyl or alkenyl substituent or with at least one phenyl substituent and optionally one or more linear or branched C1 to C3 alkyl or alkenyl substituents; - Group 4: perfume ingredients comprising at least two fused or joined C5 and / or Ce rings; - Group 5: perfume ingredients comprising a ring structure similar to camphor; - Group 6: perfume ingredients comprising at least one ring structure from C1 to C20; - Group 7: Perfume ingredients having a logP value greater than 3.5 and comprising at least one tere-butyl substituent or at least one trichloromethyl substituent; Examples of the ingredients from each of these groups are: - Group 1: 2,4-dimethyl-3-cyclohexeno-l-carbaldehyde (origin: Firmenich SA, Geneva, Switzerland), isocyclocitral, menthol, isomenthol, 2,2-dimethyl-6-methylen-lcyclohexanocarboxylate de methylo (origin: Firmenich SA, Geneva, Switzerland), nerol, terpineol, dihydroterpineol, acetato de terpenyl, acetato de dihydroterpenyl, dipentene, eucalyptol, hexilate, óxido de rosa, (S)-1,8-p-mentadien-7-ol (origin: Firmenich SA, Geneva, Switzerland), 1p-menthen-4-ol, acetato de (1RS,3RS,4SR)-3-p-mentanilo, (IR,2S,4R)-4,6,6trimethyl-bicyclo[3,1,1]heptan-2-ol, tetrahydro-4-methyl-2phenyl-2H-pyran (origin: Firmenich SA, Geneva, Switzerland), i? / conn / zznz / E / YiAi cyclohexyl acetate, cyclanol acetate, 1,4-cyclohexane diethyldicarboxylate (origin: Firmenich SA, Geneva, Switzerland), (3ARS, 6SR,7ASR)-perhydro-3,6-dimethylbenzo[B]furan-2-one (origin: Firmenich SA, Geneva, Switzerland), ( (6R)-perhydro-3,6-dimethyl-benzo[B]furan-2-one (origin: Firmenich SA, Geneva, Switzerland), 2,4,6-trimethyl-4-phenyl-l,3dioxane, 2,4,6-trimethyl-3-cyclohexene-l-carbaldehyde; Group 2: (E)-3-methyl-5-(2,2,3-trimethyl-3cyclopentene-l-yl)-4-penten-2-ol (origin: Givaudan SA, Vernier, Switzerland), (1'R, E)-2-ethyl-4-(2',2',3'-trimethyl-3'-penten-ol-2'-l-2' (origin: Firmenich SA, Geneva, Switzerland), (1'R,E)-3,3-dimethyl-5-(2',2',3'-trimethyl-3'-cyclopentene-1'yl)-4-penten-2-ol (origin: Firmenich SA, Geneva, Switzerland), 2heptylcyclopentanone, acetate de methyl-cis-3-oxo-2-pentyl-lcyclopentane (origin: Firmenich SA, Geneva, Switzerland), 2,2,5trimethyl-5-pentyl-l-cyclopentanone (origin: Firmenich SA, Geneva, Switzerland), 3,3-dimethyl-5-(2,2,3-trimethyl-3-cyclopenten1-yl)-4-penten-2-ol (origin: Firmenich SA, Geneva, Switzerland), 3methyl-5-(2,2,3-trimethyl-3-cyclopenten-l-yl)-2-pentanol (origin, Givaru and Vernier, SA); - Group 3: damascones, 1-(5,5-dimethyl-l-cyclohexen1-yl)-4-penten-l-one (origin: Firmenich SA, Geneva, Switzerland), necthalactone ((l'R)—2— [2 — (4*-methi1-3'-cyclohexene-1-clopentanone)]] alpha-ionone, beta-ionone, damascenone, mixture of 1-(5,5-dimethyl-l-cyclohexen-l-yl)-4 i? / conn / zznz / E / YiAi penten-l-one and 1-(3,3-dimethyl-l-cyclohexen-l-yl)-4-nabrate (Origen: Firgen, SA Switzerland), 1-(2,6,6-trimethyl1-cyclohexene-l-yl)-2-butene-l-one (origin: Firmenich SA, Geneva, Switzerland), (IS,1'R)-[1-(3',3'-dimethyl-1'cyclohexyl)ethoxycarbonyl]methyl propanoate (origin: Firmenich SA, Geneva, Switzerland), 2-tert-butyl-l-cyclohexyl acetate (origin: International Flavors and Fragrances, EUA), 1(2,2,3, 6-tetramethyl-cyclohexyl)-3-hexanol (origin: Firmenich SA, Geneva, Switzerland), trans-1-(2,2,6-trimethyl-l-cyclohexyl)-3hexanol (origin: Firmenich SA, Geneva, Switzerland), (E)-3-methyl-4(2,6,6-trimethyl-2-cyclohexen-l-yl)-3-buten-2-one, terpenyl isobutyrate, 4-(1,1-dimethylethyl)-1-cyclohexyl acetate (origin: Firmenich SA, Geneva, Switzerland), 8-methoxy-1p-menthenyl, propanoate (IS,1'R)-2-[1-(3',3'-dimethyl-1'cyclohexyl)ethoxi]-2-methylpropyl (origen: Firmenich SA, Ginebra, Suiza), para terc-butylcyclohexanone, mentenethiol, 1methyl-4-(4-methyl-3-pentenyl)-3-cyclohexeno-l-carbaldehido, cyclohexylpropionate de alylo, cyclohexylo salicylate, 2-methoxy-4-methylphenyl methyl carbonate, ethyl carbonate 2-methoxy-4-methylphenyl, 4-ethyl-2-methoxyphenyl methyl carbonate; - Group 4: methyl cedryl ketone (origin: International Flavors and Fragrances, USA), a mixture of (1RS,2SR,6RS,7RS,8SR)-tricyclo[5.2.1.0-2,6~]dec-3-en-8-yl 2-methylpropanoate and (1RS,2SR,6RS,7RS,8SR)-tricyclo[5.2.1.0-2,6~]dec-4-en-8-yl 2-methylpropanoate, vetiverol, vetiverone, 1-(octahydro-2,3,8,8-tetramethyl-2-naphthalenyl)-1-ethanone (origin: International Flavors and Fragrances, USA), (5RS,9RS,10SR)-2,6,9,10-tetramethyl-loxaspiro[4.5]deca-3,6-diene and the isomer (5RS,9SR,10RS), 6-ethyl-2,10,1O-trimethyl-l-oxaspiro[4.5]deca-3,6-diene, 1,2,3,5,6,7-hexahydro-l,1,2,3,3-pentamethyl-4-indenone (origin: International Flavors and Fragrances, USA), a mixture of 3-(3,3-dimethyl-5-indanyl)propanal and 3-(1,1-dimethyl5-indanyl)propanal (origin: Firmenich SA, Geneva, Switzerland), 3',4-dimethyl-tricyclo[6.2.1.0(2,7)]undec-4-ene-9-spiro-2'oxirane (origin: Firmenich SA, Geneva, Switzerland), 9 / 10ethyldiene-3-oxatricyclo[6.2.1.0(2,7)]undecane, acetate de (perhydro-5,5,8A-trimethyl-2-naphthalenyl (origen: Firmenich SA, Ginebra, Suiza), octalinol, (dodecahidro-3a,6,6,9a-tetramethylnaphtho[2,1-b]furan, origin: Firmenich SA, Ginebra, Suiza), acetate de triciclo[5.2.1.0 (2,6)]dec-3-en-8-ilo and triciclo[5.2.1.0(2,6)]dec-4-en-8-ilo acetate, as well as triciclo[5.2.1.0 (2,6)]dec-3-en-8-ilo propanoate and propanoate de tricycle[5.2.1.0(2,6)]dec-4-en-8-ilo, ( + )- (1S,2S,3S)-2,6,6trimethyl-bicyclo[3.1.1]heptane-3-espiro-2'-cyclohexen-4'-ona;. - Grupo 5: alcanfor, borneol, acetato de isobornil, 8-isopropil-6-metil-biciclo[2.2.2]oct-5-eno-2-carbaldehído, pineno, campheno, 8-metoxicedrano, (8-metoxi-2,6,6,8tetrametil-triciclo[5.3.1.0(1,5)]undecane (origen: Firmenich cann / zznz / E / YiAi SA, Geneva, Switzerland), cedreno, cedrenol, cedrol, mixture of 9ethylidene-3-oxatricyclo[6.2.1.0(2,7)]undecan-4-one and 10ethylidene-3-oxatricyclo[6.2.1.0(2,7)]undecan-4-one (origin: Firmenich SA, Geneva, Switzerland), 3-methoxy-7,7-dimethyl-10methylene-bicyclo[4.3.1]decane (origin: Firmenich SA, Geneva, Switzerland); - Group 6: (trimethyl-13-oxabicyclo-[10.1.0]-trideca4,8-diene (origin: Firmenich SA, Geneva, Switzerland), Ambrettolide LG ((E)-9-hexadecen-16-olide, origin: Firmenich SA, Geneva, Switzerland), pentadecenolide (origin: Firmenich SA, Geneva, Switzerland), muscenone (3-methyl-(4 / 5)-cyclopentadecenone, origin: Firmenich SA, Geneva, Switzerland), 3-methylcyclopentadecanone (origin: Firmenich SA, Geneva, Switzerland), pentadecanolide (origin: Firmenich SA, Geneva, Switzerland), cyclopentadecanone (origin: Firmenich SA, Geneva, Switzerland), 1-ethoxyethoxy)cyclododecane (origin: Firmenich SA, Geneva, Switzerland), 1,4-dioxacycloheptadecane-5,17-dione, 4,8cyclododecadien-l-one; Group 7: (+-)-2-methyl-3-[4-(2-methyl-2propanyl)phenyl]propanal (origin: Givaudan SA, Vernier, Switzerland), 2,2,2-trichloro-l-phenylethyl acetate. Preferably, the perfume comprises at least 30%, preferably at least 50%, and more preferably at least 60% of ingredients selected from groups 1 to 7, as defined above. More preferably, the perfume cann / zznz / E / YiAi comprises at least 30%, and more preferably at least 50%, of ingredients from groups 3 to 7, as defined above. Even more preferably, the perfume comprises at least 30%, and more preferably at least 50%, of ingredients from groups 3, 4, 6, or 7, as defined above. According to another preferred embodiment, the perfume comprises at least 30%, preferably at least 50%, more preferably at least 60% of ingredients having a logP greater than 3, preferably greater than 3.5 and even more preferably greater than 3.75. Preferably, the perfume used in the invention contains less than 10% by weight of primary alcohols, less than 15% by weight of secondary alcohols, and less than 20% by weight of tertiary alcohols. Advantageously, the perfume used in the invention contains no primary alcohols and contains less than 15% of secondary and tertiary alcohols. According to one embodiment, the oily phase (or oil-based core) comprises: 25-100% by weight of a perfume oil comprising at least 15% by weight of high-impact perfume raw materials having a Log T<-4, and - 0-75% by weight of a density equilibrium material having a density greater than 1.07 g / cm3. The nature of the high-impact perfume raw materials i? / conn / zznz / E / YiAi having a Log T<-4 and the density equilibrium material having a density greater than 1.07 g / cm3 are described in WO2018115250, the contents of which are included for reference. The term biocide refers to a chemical substance that has the ability to kill living organisms (e.g., microorganisms) or to reduce or prevent their growth and / or accumulation. Biocides are commonly used in medicine, agriculture, forestry, and industry, where they prevent contamination of, for example, water, agricultural products (including seeds), and pipelines. A biocide can be a pesticide, including fungicides, herbicides, insecticides, algaecides, molluscicides, acaricides, and rodenticides; and / or an antimicrobial agent such as germicides, antibiotics, antibacterials, antivirals, antifungals, antiprotozoals, and / or antiparasitics. As used in this document, a pest control agent refers to a substance that repels or attracts pests, or reduces, inhibits, or promotes their growth, development, or activity. Pests are any living organism—animal, plant, or fungus—that is invasive or harmful to other plants or animals. Pests include insects, particularly arthropods, mites, spiders, fungi, weeds, bacteria, and other microorganisms. i? / cann / zznz / E / YiAi According to one particular embodiment, the hydrophobic material is free of any active ingredient (such as perfume). According to this particular embodiment, it preferably comprises hydrophobic solvents, preferably selected from the group consisting of isopropyl myristate, triglycerides (e.g., Neobee® MCT oil, vegetable oils), D-limonene, silicone oil, mineral oil, and mixtures thereof with optionally hydrophilic solvents, preferably selected from the group consisting of 1,4-butanediol, benzyl alcohol, triethyl citrate, triacetin, benzyl acetate, ethyl acetate, propylene glycol (1,2-propanediol), 1,3-propanediol, dipropylene glycol, glycerol, glycol ethers, and mixtures thereof. According to any embodiment of the invention, the hydrophobic material represents between approximately 10% and 60% w / w, or even between 15% and 45% w / w, by weight, with respect to the total weight of the oily phase. According to a particular modality, the oily phase is essentially made up of the polyfunctional monomer and a perfume or flavoring oil. Polymer coating According to one embodiment, the polymeric coating comprises (or is made of) a material selected from the group consisting of polyurea, polyurethane, polyamide, polyester, polyacrylate, polysiloxane, polycarbonate, polysulfonamide, urea and formaldehyde polymers, melamine and formaldehyde, melamine and urea, or melamine and glyoxal and mixtures thereof. According to a particular modality, the material is polyurea and / or polyurethane. According to one modality, the polymeric material is present in an amount less than 20% by weight based on the total weight of the microcapsule. According to another modality, the polymeric material is present in an amount less than 10% by weight based on the total weight of the microcapsule. According to another modality, the polymeric material is present in an amount less than 6% by weight based on the total weight of the microcapsule. According to one modality, the polymeric material is present in an amount less than 12% by weight based on the total weight of the microcapsule suspension. According to another modality, the polymeric material is present in an amount less than 6% by weight based on the total weight of the microcapsule suspension. According to another modality, the polymeric material is present in an amount less than 3% by weight based on the total weight of the microcapsule suspension. In fact, it has been noted that even with a reduced amount of the polymeric material that forms the coating, the microcapsules still show good stability in consumer products. Chitosan particles According to the invention, the chitosan comprising the coating consists of solid particles. According to one modality, the chitosan particles are interspersed within the coating. According to one method, solid particles can be dispersed in water to form a homogeneous suspension of particles. The preferred chitosan particles are those with an average diameter of 5 pm at most, more preferably 3 pm at most. The relative proportion of chitosan particles, with respect to the hydrophobic material, may be between 1:1 and 1:300, preferably between 1:1 and 1:100. The chitosan particles are contained within the polymeric shell, meaning that they preferentially participate in the formation of the polymeric shell and have covalent bonding interactions with the polymeric shell, or are incorporated into the polymeric shell and / or adhere to the polymeric shell under non-covalent interactions. According to a particular embodiment, chitosan particles are crosslinked chitosan particles. The chitosan particles are preferably crosslinked with a crosslinking agent selected from the group consisting of water-soluble inorganic polyanions, water-soluble dialdehydes or polyaldehydes, and mixtures thereof. The water-soluble inorganic polyanions may include phosphate-based, silicate-based, sulfate-based, borate-based salts, and mixtures thereof. According to a particular formulation, the crosslinking agent is selected from the group consisting of sodium triphosphate, sodium hexametaphosphate, trisodium trimetaphosphate, sodium pyrophosphate, sodium phosphate, and mixtures thereof. More specifically, the crosslinking agent is sodium triphosphate. According to one embodiment, the weight ratio between the chitosan polymer (i.e., chitosan) and the crosslinking agent in the crosslinked chitosan particles is between 50:1 and 1:20, particularly between 50:1 and 1:10, more particularly between 20:1 and 1:1. According to a particular modality, the core-shell microcapsule comprises: a) an oil-based core comprising a perfume oil; and b) a polyurea-based coating comprising crosslinked chitosan particles, wherein the chitosan particles are preferably crosslinked with a phosphate-based salt, preferably sodium triphosphate. i? / conn / zznz / E / YiAi According to one modality, the cross-linked chitosan particles are embedded within the polyurea coating. Optional components When the microcapsules are in the form of a suspension, the microcapsule suspension comprises auxiliary ingredients selected from the group of thickening / rheology-modifying agents, antimicrobial agents, opacifying agents, mica particles, salt, pH stabilizers / buffering ingredients, preferably in an amount between 0 and 15% by weight based on the total weight of the suspension. According to another embodiment, the microcapsule suspension of the invention comprises an additional free (i.e., non-encapsulated) perfume, preferably in an amount between 5 and 50% by weight based on the total weight of the suspension. Optional external coating According to a particular embodiment of the invention, the microcapsules according to the invention comprise an external coating material selected from the group consisting of a polysaccharide, a cationic polymer, and mixtures thereof to form an external coating for the microcapsule. Polysaccharide polymers are well known to a person skilled in the art. The preferred non-ionic polysaccharides are selected from the group consisting of locust bean gum, xyloglucan, guar gum, hydroxypropyl guar, hydroxypropyl cellulose, hydroxypropyl methylcellulose, pectin, and mixtures thereof. According to a particular modality, the coating consists of a cationic coating. Cationic polymers are also well known to a person skilled in the art. Preferred cationic polymers have cationic charge densities of at least 0.5 meq / g, more preferably at least approximately 1.5 meq / g, but also preferably less than approximately 7 meq / g, and more preferably less than approximately 6.2 meq / g. The cationic charge density of cationic polymers can be determined by the Kjeldahl method as described in the U.S. Pharmacopeia under Chemical Tests for the Determination of Nitrogen. Preferred cationic polymers are selected from those containing units comprising primary, secondary, tertiary, and / or quaternary amine groups, which may either form part of the main polymer chain or be carried by a side substituent directly attached thereto. The weighted average molecular weight (Mw) of the cationic polymer is preferably between 10,000 and 3.5M Dalton, more preferably between 50,000 and 2M Dalton. i? / conn / zznz / E / YiAi According to a particular modality, cationic polymers based on acrylamide, methacrylamide, N-vinylpyrrolidone, quaternized N,N-dimethylaminomethacrylate, diallyldimethylammonium chloride, quaternized vinylimidazole (3-methyl-l-vinyl-lH-imidazole-3-io chloride), vinylpyrrolidone, acrylamidopropyltrimonium chloride, cassia hydroxypropyltrimonium chloride, guar hydroxypropyltrimonium chloride or polygalactomannan 2-hydroxypropyltrimethylammonium chloride ether, starch hydroxypropyltrimonium chloride and cellulose hydroxypropyltrimonium chloride will be used.Preferably, the copolymers will be selected from the group consisting of polyquaternium-5, polyquaternium-6, polyquaternium-7, polyquaternium-10, polyquaternium-11, polyquaternium-16, polyquaternium-22, polyquaternium-28, polyquaternium-43, polyquaternium-44, polyquaternium-46, hydroxypropyltrimonium chloride. cassia, hydroxypropyltrimonium chloride of guar or 2-hydroxypropyltrimethylammonium chloride ether of polygalactomannan, hydroxypropyltrimonium chloride of starch and hydroxypropyltrimonium chloride of cellulose. Specific examples of commercially available products include Saleare® SC60 (acrylamide acrylamide acrylamide cationic copolymer, source: BASF) or Luviquat®, such as PQ 11N, FC 550 i? / cann / zznz / E / YiAi or Style (polyquaternium-11 to 68 or vinylpyrrolidone quaternized copolymers, source: BASF), or also Jaguar® (C13S or C17, source: Rhodia). According to any of the preceding embodiments of the invention, an amount of the polymer described above is added, ranging from approximately 0% to 5% w / w, or even from approximately 0.1% to 2% w / w, the percentage being expressed on a w / w basis relative to the total weight of the suspension. A person skilled in the art clearly understands that only a portion of the added polymers will be incorporated / deposited onto the microcapsule coating. PROCESS FOR PREPARING THE CORE-SHAPED MICROCAPSULE The core-shell microcapsules of the invention can be prepared according to different processes depending mainly on the nature of the polymer wall. Another object of the invention is a process for preparing core-shell microcapsules as defined above, wherein the process comprises the steps of: 1) suspend chitosan particles in water to form an aqueous phase; 2) prepare an oily phase comprising a hydrophobic material, preferably a perfume oil; 3) Add the oily phase to the aqueous phase and mix them to form a Pickering oil-in-water emulsion, under conditions that allow the formation of core-shell microcapsules by means of interfacial polymerization and / or interfacial reaction, wherein a polyfunctional monomer is added in step 1) in the aqueous phase and / or in step 2) in the oily phase. According to one modality, in step 3), the oily phase is added to the aqueous phase under conditions that allow the reaction of the polyfunctional monomer to form a polymeric coating at the oil-water interface in the presence of chitosan particles. According to one particular embodiment, interfacial polymerization and / or interfacial reaction takes place between the polyfunctional monomer and the chitosan particles. In this embodiment, the coating is formed by the reaction between the polyfunctional monomer in oil, with water, and chitosan at the oil-water interface. According to one modality, the polyfunctional monomer is added to the oily phase in step 2). The above modality is particularly suitable when the polyfunctional monomer is oil-soluble (e.g., when polyisocyanate is used as a polyfunctional monomer). According to one modality, the polyfunctional monomer i? / cann / zznz / E / YiAi is added to the aqueous phase in step 1). The above modality is particularly suitable when the polyfunctional monomer is water-soluble (e.g., when a melamine resin is used as a polyfunctional monomer). According to one embodiment, a first polyfunctional monomer is added to the aqueous phase in step 1) (e.g., a melamine resin) and a second polyfunctional monomer (e.g., a polyisocyanate) is added to the oily phase in step 2). According to a particular embodiment, the process of the invention comprises the step of adding a polymeric emulsifier in step 1) in the aqueous phase. A polymeric emulsifier is understood to be an emulsifier that has both a polar group with an affinity for water (hydrophilic) and a non-polar group with an affinity for oil (lipophilic). The hydrophilic part dissolves in the aqueous phase, and the hydrophobic part dissolves in the oil phase, forming a film around the droplets. The chitosan particles used in the present invention are not polymeric emulsifiers. The chitosan particles belong to the colloidal particle stabilizer. This optional polymeric emulsifier helps stabilize oil flakes in the presence of chitosan particles. This modality may be particularly suitable when the concentration of chitosan particles is low. The polymeric emulsifier can be an ionic or non-ionic surfactant. Non-limiting examples of non-ionic polymers include polyvinyl alcohol, cellulose derivatives such as hydroxyethylcellulose, polyethylene oxide, copolymers of polyethylene oxide and polyethylene oxide or polypropylene, copolymers of alkyl acrylates and N-vinylpyrrolidone, and non-ionic polysaccharides. Ionic polymers include acrylamide and acrylic acid copolymers, an acidic anionic surfactant (such as sodium dodecyl sulfate), acrylic copolymers having a sulfonate group, and copolymers of vinyl ethers and maleic anhydride, and an ionic polysaccharide. According to one modality, during the process, no polymeric emulsifier is added at any stage of the process. According to a particular embodiment, the process of the invention comprises the step of adding a colloidal stabilizer or colloidal particle stabilizer (in addition to the chitosan particles), in step 1), in the aqueous phase. According to a particular embodiment, the process of the invention comprises the step of adding a reagent in step 1) and / or step 3). This optional reagent may participate in the formation of the microcapsule shell. The reagent may be water-soluble or water-suspended. Examples of suitable reagents include alcohols, amines, phenols, phenols, (meth)acrylates, epoxides, anhydrides with two or more functionalities, polyalkoxysilane, melamine-formaldehyde resin, melamine-glyoxal resin, and mixtures thereof. When a reagent is added, it can also react with the polyfunctional monomer to form a polymer shell. According to this method, in addition to the reagent, chitosan particles also participate in the formation of the polymer shell. Figure 1 illustrates the formation of a Pickering emulsion when chitosan particles or crosslinked chitosan particles are used. According to one particular embodiment, the microcapsules according to the invention are prepared in the absence of any molecular surfactant (also called a polymeric emulsifier). In the first stage of the process, the chitosan particles are dispersed in an aqueous phase. Typically, this is done using high mechanical agitation. When chitosan particles are not cross-linked, the particles can be obtained by: (i) the dissolution of chitosan in water under acidic conditions, typically at a pH between 3 and 5; and (ii) the increase of pH to form chitosan particles, typically at a pH greater than 6.5. i? / conn / zznz / E / YiAi When chitosan particles are cross-linked, the particles can be obtained by: (i) dissolving chitosan in water under acidic conditions, typically at a pH between 3 and 5; and (ii) adding a crosslinking agent to the chitosan solution from step (i) to form crosslinked chitosan particles, (iii) optionally, adjusting the pH between 5 and 7. Typically, step (ii) consists of mixing the crosslinking agent and the chitosan solution obtained in step (i) during stirring or mixing. According to one modality, the total amount of chitosan particles present in the aqueous phase is between 0.01 and 10% by weight, preferably between 0.1 and 5% by weight based on the total weight of the aqueous phase. According to one embodiment, in a second step, at least one oil-soluble polyfunctional monomer is dissolved in a hydrophobic material (e.g., a perfume or flavoring oil) to form an oily phase, which is then added to the aqueous phase to form a Pickering emulsion, the average droplet size of which is between 1 and 3000 microns, preferably between 1 and 500 microns, more preferably between 5 and 50 microns. The oil-in-water Pickering emulsion is prepared, for example, using a high-speed mechanical disperser or ultrasonic dispersers at room temperature. According to one modality, the oily phase represents between 5 and 60%, preferably between 20 and 40% of the Pickering emulsion. Once the Pickering emulsion is formed, the pH value is preferably kept at 5-6, or adjusted to a value above 6.5, or adjusted to a value above 8.5 and preferably not greater than 11. However, this step can be omitted. Interfacial polymerization and / or interfacial reaction can typically be carried out at a temperature between 50 °C and 90 °C under stirring for 2 to 40 hours to complete the reaction and form hybrid microcapsules in the form of a suspension. However, the heating step can be omitted. According to one modality, the polyfunctional monomer is selected from the group consisting of at least one polyisocyanate, maleic polyanhydride, polyacid chloride, polyepoxide, acrylate monomers, polyalkoxysilane, melamine-based resin, and mixtures thereof. According to a particular modality, the monomer added in step 2) is at least one polyisocyanate having at least two isocyanate functional groups. Suitable polyisocyanates used according to the invention include aromatic polyisocyanate, aliphatic polyisocyanate, and mixtures thereof. The polyisocyanate comprises at least two, preferably at least three, but may comprise up to six, or even only four, isocyanate functional groups. According to one particular embodiment, a triisocyanate (three isocyanate functional groups) is used. According to one modality, the polyisocyanate is an aromatic polyisocyanate. The term aromatic polyisocyanate is proposed here to encompass any polyisocyanate comprising an aromatic portion. Preferably, it comprises a phenyl, toluyl, xylyl, naphthyl, or diphenyl portion, more preferably a toluyl or xylyl portion. Preferred aromatic polyisocyanates are biurets, polyisocyanurates, and trimethylolpropane adducts of diisocyanates, most preferably comprising one of the specific aromatic portions mentioned above. More preferably, the aromatic polyisocyanate is a toluene diisocyanate polyisocyanurate (commercially available from Bayer under the trade name Desmodur® RC), a toluene diisocyanate trimethylolpropane adduct (commercially available from Bayer under the trade name Desmodur® L75), a xylylene diisocyanate trimethylolpropane adduct (commercially available from Mitsui Chemicals under the trade name Takenate® D-110N).In a more preferred embodiment, aromatic polyisocyanate is a trimethylolpropane adduct of xylylene diisocyanate. According to another embodiment, the polyisocyanate is an aliphatic polyisocyanate. The term aliphatic polyisocyanate is defined as a polyisocyanate that does not comprise any aromatic portion. Preferred aliphatic polyisocyanates are a hexamethylene diisocyanate trimer, an isophorone diisocyanate trimer, a hexamethylene diisocyanate trimethylolpropane adduct (available from Mitsui Chemicals), or a hexamethylene diisocyanate biuret (commercially available from Bayer under the trade name Desmodur® N 100), of which a hexamethylene diisocyanate biuret is even more preferred. According to another embodiment, the polyisocyanate is in the form of a mixture of at least one aliphatic polyisocyanate and at least one aromatic polyisocyanate, both comprising at least two or three isocyanate functional groups, such as a mixture of hexamethylene diisocyanate biuret with a trimethylolpropane adduct of xylylene diisocyanate, a mixture of hexamethylene diisocyanate biuret with toluene diisocyanate polyisocyanurate, and a mixture of hexamethylene diisocyanate biuret with a trimethylolpropane adduct of toluene diisocyanate. More preferably, it is a mixture of hexamethylene diisocyanate biuret with a trimethylolpropane adduct of xylylene diisocyanate. Preferably, when used as a mixture, the molar ratio between aliphatic polyisocyanate and aromatic polyisocyanate ranges from 80:20 to 10:90.According to one embodiment, the polyisocyanate used in the process of the invention is present in amounts representing from 0.1 to 15%, preferably from 0.5 to 5% by weight based on the total amount of the oil phase. Optional step: optional external coating According to a particular embodiment of the invention, at the end of step 3) or during step 3), a polymer selected from the group consisting of a nonionic polysaccharide, a cationic polymer, and mixtures thereof may also be added to the suspension of the invention to form an external coating for the microcapsule. The nonionic polysaccharide and the cationic polymer are as defined above. PROCESS FOR PREPARING MICROCAPSULE POWDER Another object of the invention is a process for preparing a microcapsule powder comprising the steps defined above and an additional step consisting of subjecting the suspension obtained in step 3) to a drying process, such as spray drying, to provide the microcapsules as such, i.e., in powder form. It is understood that any standard method known to a person skilled in the art for carrying out such drying is also applicable. In particular, the suspension may be spray dried, preferably in the presence of a polymeric carrier material, such as polyvinyl acetate, polyvinyl alcohol, dextrins, natural or modified starch, vegetable gums, pectins, xanthan gums, alginates, carrageenans, or cellulose derivatives, to provide microcapsules in powder form. However, other drying methods can also be cited, such as extrusion, coating, spray granulation, fluidized bed, or even room temperature drying using materials (carrier, desiccant) that meet the specific criteria described in WO2017 / 134179. According to one particular modality, the carrier material contains a free perfume oil that may be the same as or different from the perfume in the microcapsule core. CORE-SHELL MICROCAPSULE Another object of the invention is a microcapsule obtainable by the process described above. PERFUME COMPOSITION AND CONSUMER PRODUCTS The microcapsules of the invention can be used in combination with active ingredients. Therefore, an object of the invention is a composition comprising: (i) microcapsules as defined above; (ii) an active ingredient, preferably chosen from the group consisting of a cosmetic ingredient, skin care ingredient, perfume ingredient, flavoring ingredient, odor-counteracting ingredient, bactericidal ingredient, fungicidal ingredient, pharmaceutical or agrochemical ingredient, a disinfectant ingredient, an insect repellent or attractant, and mixtures thereof. The capsules of the invention show good performance in terms of stability in a challenging environment. Another object of the present invention is a perfume composition comprising: (i) microcapsules as defined above, wherein the oil comprises a perfume; (ii) at least one ingredient selected from the group consisting of a perfumery carrier, a perfumery co-ingredient and mixtures thereof; (iii) optionally at least one perfumery adjuvant.Examples of liquid carriers that can be cited, but are not limited to, include an emulsifying system (i.e., a solvent and a surfactant system) or a solvent commonly used in perfumery. A detailed description of the nature and type of solvents commonly used in perfumery cannot be exhaustive. However, examples of solvents that can be cited that are not limited to include dipropylene glycol, diethyl phthalate, isopropyl myristate, benzyl benzoate, 2-(2-ethoxyethoxy)-1-ethanol, or ethyl citrate, which are the most commonly used.For compositions comprising both a fragrance carrier and a fragrance co-ingredient, other suitable fragrance carriers besides those specified above may also include ethanol, water / ethanol mixtures, limonene or other terpenes, isoparaffins such as those known under the trade name Isopar® (origin: Exxon Chemical), or glycol ethers and glycol ether esters such as those known under the trade name Dowanol® (origin: Dow Chemical Company). A fragrance co-ingredient herein means a compound used in a fragrance composition or preparation to impart a hedonic effect and that is not a microcapsule as defined above.In other words, for such a co-ingredient to be considered a perfumer, it must be recognized by a person skilled in the technique as having the ability to impart or modify the scent of a composition in a positive or pleasant way, and not just as having a scent. The nature and type of the perfume co-ingredients present in the fragrance composition do not warrant a more detailed description here, which in any case would not be exhaustive. A person skilled in the technique is able to select them based on their general knowledge and according to the intended use or application and the desired organoleptic effect. Generally speaking, these perfume co-ingredients belong to chemical classes as varied as alcohols, lactones, aldehydes, ketones, esters, ethers, acetates, nitriles, terpenoids, nitrogenous or sulfurous heterocyclic compounds, and essential oils, and perfume co-ingredients can be of natural or synthetic origin. In any case, many of these co-ingredients are listed in reference texts such as S. Arctander's book, Perfume and Flavour Chemicals, 1969, Montclair, New Jersey, USA.or its more recent versions, or in other works of a similar nature, as well as in the abundant patent literature in the field of perfumery. It is also understood that co-ingredients can also be compounds known to release various types of perfume compounds in a controlled manner. A perfumery adjuvant here refers to an ingredient that imparts an additional benefit, such as color, lightfastness, chemical stability, etc. A detailed description of the nature and type of adjuvant commonly used in perfume bases cannot be exhaustive, but it should be noted that these ingredients are well known to anyone skilled in the craft. Preferably, the perfume composition of i? / cann / zznz / E / YiAi according to the invention comprises between 0.01 and 30% by weight of the microcapsules as defined above. The microcapsules of the invention can be used advantageously in many fields of application and can be used in consumer products. The microcapsules can be used in a liquid form applicable to liquid consumer products, as well as in a powder form applicable to powdered consumer products. According to a particular modality, the consumer product as defined above is liquid and comprises: a) 2 to 65% by weight, with respect to the total weight of the consumer product, of at least one surfactant; b) water or a water-miscible hydrophilic organic solvent; and c) a suspension of microcapsules as defined above, d) optionally a non-encapsulated perfume. According to a particular modality, the consumer product as defined above is in powder form and comprises: a) 2 to 65% by weight, with respect to the total weight of the consumer product, of at least one surfactant; b) a microcapsule powder as defined above, i? / conn / zznz / E / YiAi c) optionally a perfume powder that is different from the microcapsules defined above. In the case of microcapsules containing a perfume oil-based core, the products of the invention can be used particularly in perfumed consumer products such as those belonging to the fine fragrance or functional perfumery sectors. Functional perfumery includes, in particular, personal care products, including hair care, body wash, skin care, and hygiene products, as well as household care products, including laundry, surface care, and air care products. Accordingly, another object of the present invention consists of a perfumed consumer product comprising, as a perfume ingredient, the microcapsules defined above or a perfume composition as defined above.The perfume element of the consumer product may be a combination of perfume microcapsules as defined above and a free or unencapsulated perfume, as well as other types of perfume microcapsules different from those described herein. In particular, a liquid consumer product comprises: i? / cann / zznz / E / YiAi a) 2 to 65% by weight, with respect to the total weight of the consumer product, of at least one surfactant; b) water or a water-miscible hydrophilic organic solvent; and c) a perfume composition as defined above which is another object of the invention. A powdered consumer product also includes: (a) from 2 to 65% by weight, with respect to the total weight of the consumer product, of at least one surfactant; and (b) a perfume composition as defined above that is part of the invention. Therefore, the microcapsules of the invention can be added as such or as part of a perfume composition of the invention in a perfumed consumer product. For the sake of clarity, it should be mentioned that a perfumed consumer product is defined as a consumer product that is expected to provide, among other benefits, a perfuming effect to the surface to which it is applied (e.g., skin, hair, textiles, paper, or household surfaces) or to the air (air freshener, deodorant, etc.). In other words, a perfumed consumer product according to the invention is a manufactured product comprising a functional formulation, also referred to as a base, along with beneficial agents, including an effective quantity of microcapsules according to the invention. The nature and type of the other constituents of the perfumed consumer product do not warrant a more detailed description here, which in any case would not be exhaustive. A person skilled in the art is capable of selecting them based on their general knowledge and in accordance with the nature and desired effect of the product. Base formulations of consumer products into which the microcapsules of the invention can be incorporated can be found in the abundant literature relating to such products. These formulations do not warrant a detailed description here, which in any case would not be exhaustive. A person skilled in the art of formulating such consumer products is perfectly capable of selecting the appropriate components based on their general knowledge and the available literature. Non-limiting examples of suitable scented consumer products may include a perfume, such as a fine perfume, cologne, aftershave lotion, or a lower concentration body perfume; a fabric care product, such as a liquid or solid detergent, tablets and capsules, fabric softener, dryer sheet, fabric refresher, ironing water, or bleach;a personal care product, such as a hair care product (for example, a shampoo, a hair conditioner, a coloring preparation or a hair spray), a cosmetic preparation (for example, a vanishing cream, a body lotion or a deodorant or antiperspirant), or a skin care product (for example, a perfumed soap, a shower or bath foam, a body soap, oil or gel, bath salts, or a hygiene product); an air care product, such as an air freshener or a ready-to-use powder air freshener;or a household care product, such as multipurpose cleaners, liquid or powder dishwashing products or tablets, toilet cleaners or products for cleaning various surfaces, for example, sprays and wipes intended for the treatment / refreshing of textiles or hard surfaces (floors, tiles, stone floors, etc.); a hygiene product, such as sanitary napkins, diapers, toilet paper. Another object of the invention is a consumer product comprising: - an active base for personal care, and - microcapsules as defined above or the perfume composition as defined above, wherein the consumer product is in the form of a personal care composition. The active ingredients for personal care products that can be incorporated into the microcapsules of the invention can be found in the extensive literature relating to such products. These formulations do not warrant a detailed description here, which in any case would not be exhaustive. A person skilled in the art of formulating such consumer products is perfectly capable of selecting the appropriate components based on their general knowledge and the available literature. The personal care composition is preferably chosen from the group consisting of a hair care product (e.g., shampoo, hair conditioner, coloring preparation or hair spray), a cosmetic preparation (e.g., fading cream, body lotion or deodorant or antiperspirant), or a skin care product (e.g., perfumed soap, shower or bath foam, body soap, oil or gel, bath salts or a hygiene product). Another object of the invention is a consumer product comprising: - an active base for home care or fabric care, and - microcapsules as defined above or the perfume composition as defined above, wherein the consumer product is in the form of a home care or fabric care composition. Active bases for household or fabric care products into which the microcapsules of the invention can be incorporated can be found in the extensive literature relating to such products. These formulations do not warrant a detailed description here, which in any case would not be exhaustive. A person skilled in the art of formulating such consumer products is perfectly capable of selecting the appropriate components based on their general knowledge and the available literature. Preferably, the consumer product comprises from 0.1 to 15% by weight, more preferably from 0.2 to 5% by weight, of the microcapsules of the present invention. These percentages are defined by weight with respect to the total weight of the consumer product. Of course, the above concentrations can be adjusted according to the desired beneficial effect in each product. Fabric softener An object of the invention is a consumer product in the form of a fabric softening composition comprising: an active fabric softening base; preferably selected from the group consisting of dialkyl quaternary ammonium salts, dialkyl ester quaternary ammonium salts (esterquats), Hamburg esterquat (HEQ), TEAQ (triethanolamine quat), silicones and mixtures thereof, preferably in an amount between 85 and 99.95% by weight based on the total weight of the composition, - microcapsules as defined above, preferably in an amount between 0.05 and 15% by weight, more preferably between 0.1 and 5% by weight based on the total weight of the composition. Liquid detergent An object of the invention is a consumer product in the form of a liquid detergent composition comprising: a liquid detergent active base; preferably selected from the group consisting of an anionic surfactant such as alkylbenzenesulfonate (ABS), secondary alkyl sulfonate (SAS), primary alcohol sulfate (PAS), lauryl ether sulfate (LES), methyl ester sulfonate (MES) and a non-ionic surfactant such as alkyl amines, alkanolamide, fatty alcohol poly(ethylene glycol) ether, fatty alcohol ethoxylate (FAE), ethylene oxide (EO) and propylene oxide (PO) copolymers, amine oxides, alkyl polyglucosides, alkyl polyglucosamides, preferably in an amount between 85 and 99.95% by weight based on the total weight of the composition. - microcapsules as defined above, preferably in an amount between 0.05 and 15% by weight, more preferably between 0.1 and 5% by weight based on the total weight of the composition. Solid detergent An object of the invention is a consumer product in the form of a solid detergent composition comprising: - a solid detergent active base; preferably selected from the group consisting of an anionic surfactant such as alkylbenzenesulfonate (ABS), secondary alkyl sulfonate (SAS), primary alcohol sulfate (FAS), lauryl ether sulfate (LES), methyl ester sulfonate (MES) and a non-ionic surfactant such as alkyl amines, alkanolamide, fatty alcohol poly(ethylene glycol) ether, fatty alcohol ethoxylate (FAE), ethylene oxide (EO) and propylene oxide (PO) copolymers, amine oxides, alkyl polyglucosides, alkyl polyglucosamides, preferably in an amount between 85 and 99.95% by weight based on the total weight of the composition, - microcapsules as defined above, preferably in an amount between 0.05 and 15% by weight, more preferably between 0.1 and 5% by weight based on the total weight of the composition. i? / conn / zznz / E / YiAi Shampoo / shower gel An object of the invention is a consumer product in the form of a shampoo or shower gel composition comprising: - an active shampoo or shower gel base; preferably selected from the group consisting of sodium alkyl ether sulfate, ammonium alkyl ether sulfates, alkyl amphoacetate, cocamidopropyl betaine, cocamide MEA, alkyl glucosides and amino acid-based surfactants and mixtures thereof, preferably in an amount between 85 and 99.95% by weight based on the total weight of the composition, - microcapsules as defined above, preferably in an amount between 0.05 and 15% by weight, more preferably between 0.1 and 5% by weight based on the total weight of the composition. Rinse-out conditioner An object of the invention is a consumer product in the form of a rinse-off conditioning composition comprising: an active conditioning rinse-off base; preferably selected from the group consisting of cetyltrimonium chloride, stearyltrimonium chloride, benzalkonium chloride, behentrimonium chloride and mixtures thereof, preferably in an amount between 85 and 99.95% by weight based on the total weight of the composition, - microcapsules as defined above, preferably in an amount between 0.05 and 15% by weight, more preferably between 0.1 and 5% by weight based on the total weight of the composition. Hair coloring An object of the invention is a consumer product in the form of an oxidizing composition for hair coloring comprising: - an oxidizing phase comprising an oxidizing agent and an alkaline phase comprising an alkaline agent, a dye precursor and a coupling compound; wherein the dye precursor and the coupling compound form an oxidizing hair dye in the presence of the oxidizing agent, preferably in an amount between 85 and 99.95% by weight based on the total weight of the composition, - microcapsules as defined above, preferably in an amount between 0.05 and 15% by weight, more preferably between 0.1 and 5% by weight based on the total weight of the composition. An oxidizing hair coloring composition is understood to be a composition comprising two groups of colorless dye molecules: the dye precursor and the coupling agent. Upon reacting with each other through an oxidation process, these two groups form a wide range of colored molecules (dyes) that are then trapped in the hair due to their size. In other words, the dye precursor and the coupling compound form an oxidizing hair dye in the presence of the oxidizing agent. Dye precursor and oxidizing dye precursor are used interchangeably in the present invention. Dye precursors can be aromatic compounds derived from benzene substituted with at least two electron-donating groups, such as NH₂ and OH, in the para or ortho positions to confer the property of easy oxidation. According to one modality, the dye precursors are selected from the group consisting of p-phenylene diamine, 2,5-diaminotoluene, N,N-bis(2-hydroxymethyl)-p-phenylene diamine, 4-aminophenol, 1,4-diaminobenzene, and mixtures thereof. Primary dye precursors are used in combination with coupling agents. Coupling agents are preferably aromatic compounds derived from benzene and substituted with groups, such as NH2 and OH, in the meta position. They do not produce color on their own, but rather modify the color, hue, or intensity of the colors developed by the dye precursor. According to one embodiment, the coupling agent is selected from the group consisting of resorcinol, 2-methyl resorcinol, 4-chlororesorcinol, 2,5-diaminotoluene, 1,3-diaminobenzene, 2,4-diaminophenoxyethanol HCl, 2-aminohydroxyethylaminoanisole sulfate, 4-amino-2-hydroxytoluene, and mixtures thereof. The oxidizing dye precursor is preferably used in an amount between 0.001% and 5%, preferably between 0.1% and 4% by weight based on the total weight of the composition. The use of oxidizing dye precursors and coupling agents in hair coloring formulations has been extensively described in the prior art and is well known to those skilled in the art. EP0946133A1, the contents of which are incorporated by reference, may be cited, for example. The alkaline phase comprises an alkaline agent, preferably selected from the group consisting of ammonium hydroxide, ammonium carbonate, ethanolamine, potassium hydroxide, sodium borate, sodium carbonate, triethanolamine and mixtures thereof. The alkaline agent is preferably used in an amount between 1% and 10%, preferably between 3% and 9% by weight based on the total weight of the composition. According to the invention, the coupling agent and the dye precursor in an alkaline medium form an oxidizing hair dye in the presence of the oxidizing agent. i? / conn / zznz / E / YiAi The oxidizing agent will supply the oxygen gas needed to develop color molecules and create a change in hair color. The oxidizing agent should be safe and effective for use in the compositions in this document. Preferably, the oxidizing agents suitable for use in this document shall be soluble in the compositions according to the present invention when in liquid form and / or in the form proposed for use. Preferably, the oxidizing agents suitable for use in this document shall be water-soluble. The oxidizing agents suitable for use in this document are selected from inorganic peroxygen oxidizing agents, preformed organic peroxyacid oxidizing agents, and organic peroxide oxidizing agents, or mixtures thereof. The oxidizing agent is preferably used in an amount between 5 and 30%, preferably between 5 and 25% by weight based on the total weight of the composition. Components commonly used in cosmetic compositions can be added to the hair coloring composition as defined in the present invention. Examples include surfactants, cationic polymers, oily substances, silicone derivatives, fragrances, preservatives, ultraviolet light absorbers, antioxidants, germicides, propellants, and thickeners. i? / conn / zznz / E / YiAi According to a particular modality, the hair coloring composition comprises one or more quaternary ammonium compounds, preferably selected from the group consisting of cetyltrimonium chloride, stearyltrimonium chloride, benzalkonium chloride, behentrimonium chloride and mixtures thereof, to confer benefits to a hair conditioner. Perfume composition According to a particular modality, the consumer product is in the form of a perfume composition comprising: 0.1 to 30%, preferably 0.1 to 20% of microcapsules as defined above, - 0 to 40%, preferably 3-40% perfume, and - 20-90, preferably 40-90% ethanol, by weight based on the total weight of the perfume composition. The invention will now be further described by means of the examples. It will be appreciated that the invention, as claimed, is not proposed to be limited in any way by these examples. Examples Example 1 Preparation of the microcapsules The microcapsules were prepared according to the general protocol that will be described below. i? / conn / zznz / E / YiAi The chitosan polymer was first dissolved in an acetic acid solution under stirring, and the chitosan polymer was optionally crosslinked by adding a sodium tripolyphosphate solution to form particles under stirring at a specific pH value of 4 and the pH of the suspension was increased to a pH of 6 to form particles in an aqueous phase. Next, an oil phase (including, for example, a polyisocyanate) was mixed with the aqueous phase, wherein the oil phase and / or the aqueous phase comprise a polyfunctional monomer. A Pickering emulsion was prepared using a homogenizer, Ultra Turrax, IKA T25, at 24,000 rpm for 5 minutes. The formulation is described in Tables 1-11 below. In another stage, the interfacial reaction was carried out at 80 °C under stirring for 3 hours. The microcapsules obtained are in the form of a suspension (suspension in water). Table 1 - Formulation of perfume oil i? / conn / zznz / E / YiAi Ingredients % in the oil: Ethyl 2-Methylpentanoate 3.20%, Eucalyptol 7.80%, 2,4-Dimethyl-3-cyclohexene-1-carbaldehyde 0.75%, ClO2 aldehyde 0.75%, Citronellyl nitrile 4.30% Isobornyl acetate 3.00% 2-tert-butyl-l-cyclohexyl acetate 9.80% Citronellyl acetate 1.30% 2-Methylundecanal 3.00% Diphenyl oxide 0.80% C12 aldehyde 1.30% Dicyclopentadiene acetate 9.85% Beta ionone 3.30% Gamma undccalactone 18.75% Hexyl salicylate 15.90% Benzyl salicylate 16.20% i? / cann / zznz / E / YiAi Table 2 - Formulation of the microcapsule preparation A Ingredient % by weight Chitosan1) 0.7 Deionized water 68.49 Acetic acid 0.69 Xylene diisocyanate trimethylolpropane adduct 0.62) Sodium tripolyphosphate 0.12 Perfume oil3) 29.4 u Origin: Shanghai Aladdin Bio-Chem Technology Co., LTD, China 2) Takenate® D-110 N (74.4% solid content), brand commercial and origin of Mitsui3)see table 1 Table 3 - Microcapsule Preparation Formulation B Ingredient % by weight Chitosan1) 0.5 Deionized water) 66.74 Acetic acid 0.68 Xylene diisocyanate trimethylolpropane adduct 0.62) Sodium tripolyphosphate 0.08 Perfume oil3) 29.4 Origin: Shanghai Aladdin Bio-Chem Technology Co., LTD, China 2> Takenate® D-110 N (74.4% solid content), trademark and origin of Mitsui 3) see Table 1 Table 4 - Microcapsule Preparation Formulation C Ingredient % by weight Chitosan1) 0.35 Deionized water 68.89 Acetic acid 0.7 Xylene diisocyanate trimethylolpropane adduct 0.62) Sodium tripolyphosphate 0.006 Perfume oil3) 29.4 D Origin: Shanghai Aladdin Bio- -Chem Technology Co., LTD, China 2) Takenate® D-110 N (74.4% solid content), trademark and origin of Mitsui3) see table 1 i? / conn / zznz / E / YiAi Table 5 - Microcapsule Preparation Formulation D Ingredient % by weight Chitosan1) 0.14 Deionized water 69.15 Acetic acid 0.7 Xylene diisocyanate trimethylolpropane adduct 0.62) Sodium tripolyphosphate 0.014 Perfume oil3^ 29.4 D Origin: Shanghai Aladdin Bio-Chem Technology Co., LTD, China 2> Takenate® D-110 N (74.4% solid content), trademark and origin of Mitsui3)see table 1 Table 6 - Microcapsule Preparation Formulation E Ingredient % by weight Chitosan1) 0.5 Deionized water 66.74 Acetic acid 0.68 Xylene diisocyanate trimethylolpropane adduct 0.452) Sodium tripolyphosphate 0.08 Perfume oil3^ 29.55 i® Origin: Shanghai Aladdin Bio-Chem Technology Co., LTD, China 2) Takenate® D-110 N (74.4% solid content), trademark and origin of Mitsui 3) see Table 1 Table 7 - Microcapsule Preparation Formulation F Ingredient % by weight Chitosan1) 0.7 Deionized water 68.61 Xylene diisocyanate trimethylolpropane adduct 0.62* Acetic acid 0.69 Perfume oil3) 29.4 i? / cann / zznz / E / YiAi1)Origin: Shanghai Aladdin Bio-Chem Technology Co., LTD, China2)Takenate® D-110 N (74.4% solid content), trademark and origin of Mitsui3)see table 1 Table 8 - Formulation of the microcapsule preparation G Ingredient % by weight Chitosan0 Deionized water Xylene diisocyanate trimethylolpropane adduct2^ Acetic acid Perfume oil3) 1.05 68.26 0.6 0.69 29.4 Origin: Shanghai Aladdin Bio-Chem Technology Co., LTD, China 2) Takenate® D-110 N (74.4% solid content), trademark and origin of Mitsui 3) See Table 1 Table 9 - Formulation of the microcapsule preparation H i? / cann / zznz / E / YiAi Ingredient % by weight Chitosan 0.7 Deionized water 68.48 Acetic acid 0.7 Trimethylolpropane adduct of 0.3 Xylene diisocyanate2) Hexamethylene diisocyanate biuret3) Sodium tripolyphosphate 0.3 Perfume oil41 29.4 D Origin: Shanghai Aladdin Bio-Chem Technology Co., LTD, China 2) Takenate® D-110 N (74.4% solid content), trademark and origin of Mitsui 3) Desmodur® N-100, trademark and origin of Covestro 4) See Table 1 Table 10 - Microcapsule Preparation Formulation I Ingredient % by weight Chitosan1^ 0.7 Deionized water 68.33 Acetic acid 0.7 Butyl methacrylate 2.0 Dimethacrylate 2.8 1,4-butanediol Tripolyphosphate of 0.12 sodium Ammonium persulfate 0.15 Benzoyl peroxide 0.15 Perfume oil2)25.0511Origin: Shanghai Aladdin Bio-Chem Technology Co., LTD, China2)see table 1 Table 11 - Formulation of the microcapsule preparation J i? / cann / zznz / E / YiAi Ingredient % by weight Chitosan1) 0.7 Deionized water 65.20 Acetic acid 0.68 Xylene diisocyanate trimethylolpropane adduct2) 0.6 Melamine-glyoxal resin3) 2.3 Sodium tripolyphosphate 0.12 Cationic acrylic copolymer4) 1.0 Perfume oil5) 29.55 i-) Origin: Shanghai Aladdin Bio- -Chem Technology Co., LTD, China 2) Takenate® D-110 N (74.4% solid content), trademark and origin of Mitsui 3) Reaction of melamine, glyoxal and 2,2-dimethoxyacetaldehyde 4) Salere® SC 60, trademark and origin of BASF 5) See Table 1 The mean size and zeta potential of the prepared microcapsules were measured (see Table 12). The size distribution of the microcapsules was controlled by means of optical microscopy and light scattering (Mastersizer 3000, Malvern). cann / zznz / E / YiAi The zeta potential of the microcapsules was determined using a Zetasizer Nano ZS apparatus (Malvern Instruments). Table 12 - Average size and zeta potential of microcapsules Microcapsules Average size d(v, 0.5) Zeta potential A 27 gm 18.7 mV B 32 μιη 15.5 mV C 16 μm 12.1 mV D 28 μm 16.5 mV E 35 μm 18.1 mV F 31 μιη 6.1 mV G 18 μm 9.0 mV H 31 μm 18.8 mV I 43 μm 26.5 mV J 47 μm 28.2 mV Example 2 Storage stability in a fabric softening composition The stability of the capsules during storage in a fabric softener was evaluated. The microcapsule suspension of the present invention was diluted in the fabric softener composition described in Table 13 at a dosage of 0.2%. The softener was stored for one month at 37 °C. The amount of perfume that had leaked from the capsules was then measured by solvent extraction and GC-FID analysis (Table 14). Table 13 - Composition of fabric softener cann / zznz / E / YiAi Product Origin % by weight Stepantex VL 90A 8.88 10% Calcium Chloride Solution 0.36 Proxel GXL Avecia 0.04 Firmenich SA Perfume 1 Water 89.72 TOTAL 100 Table 14 Oil leak measurement Capsules Leakage after 30 days (%) A 19 B 22 C 42 D 21 E 27 F 30 G 33 H 31 J 14 It can be concluded from Table 14 that the microcapsules of the present invention show good stability on challenging bases despite the low amount of polyfunctional monomer in the coating. Example 3 Olfactory performance of the microcapsules The microcapsule suspension was diluted in a softening base containing 0.11% free perfume. The sample was agitated in a turbulator at 41 rpm for 5 minutes. To approximate the dilution required by the washing machine during the rinse cycle, the sample was diluted to 2% in deionized water. One milliliter of this solution was removed and placed on blotting paper. The sample was allowed to dry for 24 hours at room temperature before processing for pre- and post-rubbing evaluation. Evaluation scale: (fragrance intensity): 1=no fragrance odor; 2=barely detectable; 3=weak; 4=moderate; 5=slightly strong; 6=intense; 7=very intense. i? / cann / zznz / E / YiAi Table 15 - Sensory analysis results of the microcapsule diluted in fabric softener and applied to blotting paper Microcapsules Before rubbing After rubbing A 2.4 5.2 B 2.8 5.8 C 2.6 5.0 D 2.3 5.5 E 2.8 4.8 F 2.2 4.3 G 2.4 4.4 H 2.6 5.1 I 2.9 4.8 J 2.1 5.6 cann / zznz / E / YiAi The microcapsules show a good rubbing effect, which confirms efficient encapsulation. Example 4 Liquid detergent composition The AG microcapsules of the present invention were dispersed in a liquid detergent base described in Table 16 to obtain a concentration of the encapsulated perfume oil of 0.22%. Table 16 - Liquid detergent composition Ingredients Concentration [% by weight] Sodium C14-17 alkyl sec sulfonate 7 C12-18 and C18 unsaturated fatty acids 7.5 C12 / 14 fatty alcohol polyglycol ether with 7 mol EO3 17 Triethanolamine 7.5 Propylene glycol 11 Citric acid 6.5 Potassium hydroxide 9.5 Protease 0.2 Amylase 0.2 Mannanase 0.2 Stcarcth-204' acrylates / methacrylate structuring crosspolymer 6 Deionized water 27.4 i? / conn / zznz / E / YiAi 1) HostapurSAS 60; Origin: Clariant 2) Edenor K 12-18; Origin: Cognis 3) Genapol LA 070; Origin: Clariant 4) Aculyn 88; Origin: Dow Chemical Example 5 Rinse-out conditioner The AG microcapsules of the present invention were dispersed in a rinse-off conditioning base described in Table 17 to obtain a concentration of the encapsulated perfume oil of 0.5%. Table 17 - Composition of rinse-out conditioner Ingredients Concentration [% by weight] A Deionized water 81.8 Behentrimonium chloride 11 2.5 Hydroxyethylcellulose 2) 1.5 B Cetearyl alcohol 3) 4 Glyceryl stearate (and) PEG-100 stearate 4) 2 Behentrimonium methosulfate (and) Cetyl alcohol (and) Butylene glycol 5) 4 Ethoxy (20) stearyl alcohol 6) 1 c Amodimethicone (and) Trideceth-12 (and) Cetrimonium chloride 71 3 Chlorhexidine digluconate 8) 20% aqueous solution 0.2 D 10% aqueous citric acid solution to pH 3.5-4 qs TOTAL: 100 i? / cann / zznz / E / YiAi 1) Genamin KDM P, Clariant 2) Tylose H10 Y G4, Shin Etsu 3) Lanette O, BASF 4) Arlacel 165-FP-MBAL-PA-(RB), Croda 5) Incroquat Behenyl TMS-50-MBAL-PA-(ΜΗ) HA4112, Croda 6) SP Brij S20 MBAL-PA(RB), Croda 7) Xiameter DC MEM-0949 Emulsion, Dow Corning 8) Alpha Aesar Example 6 Shampoo composition The AG microcapsules of the present invention were weighed and mixed into a shampoo composition to add the equivalent of 0.2% perfume. Table 18 - Shampoo Composition Ingredients Concentration [% by weight] A Deionized water 44.4 Polyquaternium-10 0.3 Glycerin 85% 2) 1 DMDM ​​hydantoin 3) 0.2 B Sodium laureth sulfate 41 28 Cocamidopropyl betaine 5) 3.2 Disodium cocoamphodiacetate 6) 4 Ethoxy (20) stearyl alcohol 6) 1 C Sodium laureth sulfate 4) 3 Glyceryl laureate 7) 0.2 D Deionized water 1 Methylparaben de sodium 8) 0.1 E 10% aqueous solution of sodium chloride 15 10% aqueous solution of citric acid up to pH 5.5-6 cs Perfume 0.5 TOTAL: 100 i? / cann / zznz / E / YiAi 1) Ucare Polymer JR-400, Noveon 2) Switzerland 3) Glydant, Lonza 4) Texapon NSO IS, Cognis 5) Tego Betain F 50, Evonik 6) Amphotenside GB 2009, Zschimmer & Schwarz 7) Monomuls 90 L-12, Gruenau 8) Monosodium nipagin, NIPA Example Composition of the antiperspirant emulsion for a rotary ball device The AG microcapsules of the present invention were weighed and mixed into an antiperspirant emulsion composition for a rotating ball device to add the equivalent of 0.2% perfume. Table 19 - Antiperspirant composition i? / conn / zznz / E / YiAi Ingredient Quantity (% by weight) Stcarcth-21' (part A) 3.25 Steareth-212) (part A) 0.75 PPG-153 stearyl ether3) (part A) 4 Deionized water (part B) 51 50% aqueous aluminum chlorohydrate solution4) (part C) 40 Fragrance (part D) 1 1) BRIJ 72; origin: ICI 2) BRIJ 721; origin: ICI 3) ARLAMOL E; origin: UNIQEMA-CRODA 4) LOCRON L; origin: CLARIAN Parts A and B were heated separately to 75 °C; part A was added to part B under stirring, and the mixture was homogenized for 10 minutes. The mixture was then cooled under stirring; and part C was added slowly when the mixture reached 45 °C and part D when the mixture reached 35 °C, while stirring. The mixture was then cooled to room temperature. Example 8 Composition of the shower gel The AG microcapsules of the present invention were weighed and mixed in the following composition to add the equivalent of 0.2% perfume. Table 20 - Composition of the shower gel cann / zznz / E / YiAi Ingredients Quantity (% by weight) Function Deionized Water 49.350 Solvent Tetrasodium EDTA 0.050 Chelating Agent Acrylates Copolymer 6.000 Thickener Sodium C12-C15 Pareth Sulfate 35.000 Surfactant 20% Aqueous Sodium Hydroxide Solution 1.000 pH Adjuster Cocamidopropyl Betaine 8.000 Surfactant Methylchloroisothiazolinone and Methylisothiazolinone 0.100 Preservative Citric Acid (40%) 0.500 pH Adjuster 1) EDETA B POWDER; trademark and origin: BASF 2) CARBOPOL AQUA SF-1 POLYMER; trademark and origin: NOVEON 3) ZETESOL AO 328 U; trademark and origin: ZSCHIMMER & SCHWARZ 4) TEGO-BETAIN F 50; trademark and origin: GOLDSCHMIDT 5) KATHON GC; trademark and origin: ROHM & HASS. It is hereby stated that, as of this date, the best method known to the applicant for putting the aforementioned invention into practice is the one that is clear from the present description of the invention.

Claims

1. A core-shell microcapsule, characterized in that it comprises: a) an oil-based core comprising a hydrophobic material, preferably a perfume oil; and b) a polymeric shell comprising chitosan particles.

2. The microcapsule according to claim 1, characterized in that the polymeric shell is made of a polymeric material selected from the group consisting of polyurea, polyurethane, polyamide, polyacrylate, polysiloxane, polycarbonate, polysulfonamide, urea-formaldehyde, melamine-formaldehyde resin, melamine-urea resin, melamine-glyoxal resin, gelatin / gum arabic, and mixtures thereof.

3. The microcapsule according to claim 2, characterized in that the polymeric shell is made of a material selected from the group consisting of polyurea, polyurethane, and mixtures thereof. 4.The microcapsule according to any of the preceding claims, characterized in that the chitosan particles are crosslinked chitosan particles.

5. The microcapsule according to claim 4, characterized in that the chitosan particles are crosslinked with a crosslinking agent selected from the group consisting of water-soluble inorganic polyanions, dialdehydes or water-soluble polyaldehydes, and mixtures thereof.

6. The microcapsule according to claim 5, characterized in that the crosslinking agent is selected from the group consisting of sodium triphosphate, sodium hexametaphosphate, trisodium trimetaphosphate, sodium pyrophosphate, sodium phosphate, and mixtures thereof.

7. The microcapsule according to any of the preceding claims, characterized in that the polymeric shell comprises less than 20% by weight of a polymeric material based on the total weight of the microcapsule. 8.The microcapsule according to any of the preceding claims, characterized in that it comprises: a) an oil-based core comprising a perfume oil; and b) a polyurea-based shell comprising crosslinked chitosan particles, wherein the chitosan particles are crosslinked with a phosphate-based salt, preferably sodium triphosphate.

9. A process for preparing core-shell microcapsules according to any of claims 1-8, characterized in that it comprises the steps of: 1) suspending chitosan particles in water to form an aqueous phase; 2) prepare an oily phase comprising a hydrophobic material, preferably a perfume oil; 3) Adding the oil phase to the aqueous phase and mixing them to form an oil-in-water Pickering emulsion, under conditions that allow the formation of core-shell microcapsules by means of interfacial polymerization and / or interfacial reaction, wherein a polyfunctional monomer is added in step 1) to the aqueous phase and / or in step 2) to the oil phase.

10. The process according to claim 9, characterized in that the polyfunctional monomer is selected from the group consisting of at least one polyisocyanate, polymaleic anhydride, polyhydrochloride, polyepoxide, acrylate monomers, polyalkoxysilane, melamine-based resin, and mixtures thereof.

11. The process according to claims 10 or 11, characterized in that the chitosan particles are obtained by: (i) dissolving chitosan in water under acidic conditions; and (ii) increasing the pH to form chitosan particles. 12.The process according to claims 10 or 11, characterized in that the chitosan particles are crosslinked and are obtained by: (i) dissolving the chitosan in water under acidic conditions; and (ii) adding a crosslinking agent to the chitosan solution of step (i) to form crosslinked chitosan particles.

13. The process according to claims 9-12, characterized in that the total amount of chitosan particles present in the aqueous phase is between 0.01 and 10% by weight, preferably between 0.1 and 5% by weight based on the total weight of the aqueous phase.

14. The process according to claims 9-13, characterized in that the oil phase represents between 5 and 60%, preferably between 20 and 40%, of the Pickering emulsion. 15.A consumer product, characterized in that it comprises: - an active base for personal care, and microcapsules according to claims 1-8, wherein the consumer product is in the form of a personal care composition.

16. A consumer product, characterized in that it comprises: - an active base for household care or fabric care, and microcapsules according to claims 1-8, wherein the consumer product is in the form of a household care or fabric care composition.