Method for preparing microcapsules

Abstract

The invention relates to a novel method for preparing microcapsules free of melamine-formaldehyde. Microcapsules obtainable by said method are also an object of the invention. Perfuming compositions and consumer products comprising said capsules, in particular perfumed consumer products in the form of home care or personal care products, are also part of the invention.

Description

[0001] This invention is a divisional application of patent application No. 201780046559.X, entitled "Method for Preparing Microcapsules," filed on July 26, 2017. Technical Field

[0002] This invention relates to a novel method for preparing melamine-formaldehyde-free microcapsules. Microcapsules obtainable by this method are also an object of this invention. Fragrance compositions and consumer products containing said capsules, particularly fragranced consumer products in the form of home care or personal care products, are also part of this invention. Background Technology

[0003] One of the challenges facing the fragrance industry is that the olfactory effects, particularly the "top notes," derived from odorous compounds are lost relatively quickly due to their volatility. To tailor the release rate of volatiles, delivery systems such as fragrance-containing microcapsules are needed to protect and subsequently release the payload of the nucleus upon triggering. A key requirement for these systems in the industry is their ability to remain suspended in challenging base materials without physical dissociation or degradation. This is referred to as performance in terms of delivery system stability. For example, the stability of microcapsules is particularly challenging for aromatic personal and household cleaners containing detergents with high levels of aggressive surfactants.

[0004] Amino-plastic microcapsules formed from melamine-formaldehyde resin have been widely used to encapsulate hydrophobic active substances, thereby protecting these substances and providing their controlled release. However, when used in consumer products containing surfactants (such as fragrance products), especially after prolonged storage at high temperatures, amino-plastic capsules encounter stability issues. In such products, even if the capsule shell remains intact, the encapsulated active agent tends to leak out of the capsule through diffusion across the wall due to the presence of surfactants that can dissolve the encapsulated active substance in the product base. This leakage reduces the efficiency of the capsule in protecting the active substance and providing its controlled release.

[0005] Various strategies have been described to improve the stability of oil-based microcapsules. Crosslinking of the capsule wall with chemical groups such as polyamines and polyisocyanates has been described as a method to improve microcapsule stability. WO 2011 / 154893 discloses a method for preparing polyurea microcapsules, for example, using a combination of aromatic and aliphatic polyisocyanates at specific relative concentrations. Compared to amino plastics, polyurea-based microcapsules have the added advantage of being free of melamine-formaldehyde. However, these capsules are not always satisfactory in terms of mechanical properties because they are less brittle, which can negatively impact their olfactory properties, represented by the intensity of the odor perceived during handling and, for example, after intentional breakage by friction.

[0006] WO2013 / 068255 also proposes a solution for developing “formaldehyde-free” capsules in response to growing industrial demand due to regulatory concerns. The described capsules are obtained by a method involving the use of an oligomer composition prepared by reacting a polyamine component with an aldehyde and a protic acid catalyst, followed by forming an emulsion with the oligomer composition, oil, and a crosslinking agent prior to final heating and cooling. The polyamine component is essential in the disclosed method because it participates in the wall structure and capsule performance in reducing oil leakage. However, the use of polyamines in this method limits the application range of the resulting capsules because some components may be unapproved.

[0007] There remains a need to simplify processes and formulations, and to use more environmentally friendly materials without compromising capsule performance, particularly in terms of stability in challenging media such as consumer product bases, and to provide good performance in the delivery of active ingredients, such as olfactory performance in the case of flavored ingredients. This invention offers a solution to these problems based on a novel method for preparing microcapsules, which utilizes a combination of bio-derived polymers and specific acids in the absence of polyamine components. Summary of the Invention

[0008] It has been surprisingly discovered that efficient melamine-formaldehyde-free microcapsules encapsulating active ingredients can be obtained by combining anionic bio-derived polyols with specific protic acid catalysts without the use of amines or polyamines. Therefore, the method of the present invention provides a solution to the aforementioned problems because it allows the preparation of poly(urea-carbamate) capsules with simplified formulations using bio-derived materials. Unexpectedly, the applicant has found that only specific acids can yield capsules with the desired stability in challenging base materials. In particular, acetic acid, widely disclosed as a protic acid component in polycondensation processes, cannot be stably encapsulated by the method of the present invention.

[0009] In its first embodiment, the present invention relates to a method for preparing a melamine-formaldehyde-free poly(urea-carbamate) core-shell microcapsule slurry, comprising the following steps:

[0010] 1) An oil, preferably containing spices or seasonings, is mixed with at least one polyisocyanate having at least three isocyanate functional groups to form an oil phase, provided that the oil phase is substantially free of diisocyanates.

[0011] 2) Under acidic conditions, preferably at a pH below 4.5, an aqueous phase is prepared, comprising at least one anionic bio-derived polyol and a catalyst comprising a protic acid with a pKa below 4.5;

[0012] 3) The oil phase is added to the aqueous phase to form an oil-in-water dispersion;

[0013] 4) Perform a curing step to form a microcapsule slurry;

[0014] 5) Optionally, at least one cationic copolymer may be added to the capsule slurry;

[0015] The method is carried out without the addition of large amounts of amines or polyamines at any stage of the process.

[0016] In a second embodiment, the present invention relates to melamine-formaldehyde-free poly(urea-carbamate) microcapsules that can be obtained by the above method, comprising an oil-based core and a shell, the shell being substantially composed of a polymerized polyisocyanate and an anionic bio-derived polyol, the polymerized polyisocyanate being formed of at least one polyisocyanate containing at least three isocyanate functional groups.

[0017] Another object of the present invention is to produce a flavoring composition containing the following substances:

[0018] (i) Microcapsules as defined above, wherein the oil contains a fragrance;

[0019] (ii) at least one ingredient selected from the group consisting of flavor carriers and flavor auxiliaries; and

[0020] (iii) Optionally, at least one flavoring adjuvant.

[0021] Consumer products containing the following substances are also part of this invention:

[0022] a) At least one surfactant in an amount of 2 to 65% by weight relative to the total weight of the consumer product;

[0023] b) Water or a water-miscible hydrophilic organic solvent; and

[0024] c) Microcapsules or flavored compositions as defined above. Detailed Implementation

[0025] Unless otherwise stated, percentages (%) represent the weight percentage of the composition.

[0026] The phrase "no large amounts of amines or polyamines are added at any stage of the method" means that, if present, the amount of amines or polyamines added must be sufficiently low so as not to significantly alter the properties of the microcapsule shell if reacted with polyisocyanates. Typically, the amount of amine functionality that can be added in the method of the present invention is less than 50 mol% of the isocyanate functionality, preferably less than 25 mol%, and most preferably less than 10 mol%.

[0027] According to a specific implementation plan, no amines or polyamines are added at any stage of the method.

[0028] "Active ingredient" refers to a single compound or a combination of multiple components.

[0029] "Flavor or flavoring oil" refers to a single flavoring or flavoring compound or a mixture of several flavoring or flavoring compounds.

[0030] "Bio-derived polyols" refer to chemically modified polyols derived from polyols produced by living organisms. Bio-derived polyols include both natural and artificial components, characterized by a molecular weight distribution ranging from 1,000 (1,000) to 1,000,000,000 (1 billion) Daltons. These macromolecules can be carbohydrates (based on sugars), proteins (based on amino acids), or a combination of both (gum), and can be linear, cross-linked, or branched.

[0031] "Consumer goods" or "final products" refer to manufactured goods intended for distribution, sale, and use by consumers.

[0032] Glyoxylic acid and 2-oxoacetic acid are used interchangeably in this invention.

[0033] For clarity, the term "dispersion" in this invention refers to a system in which particles are dispersed in a continuous phase of different compositions and specifically includes suspensions or emulsions.

[0034] It has been found that melamine- and formaldehyde-free microcapsules with good overall performance can be obtained by using anionic bio-derived polymers in combination with specific catalytic acids without the addition of (poly)amines. These microcapsules achieve a proper balance between stability in surfactant-based products and the delivery of active ingredients (i.e., odor perception in the case of fragrances). It is surprising that the properties of acids, which may affect the stability of capsules obtained by similar methods, have never been publicly disclosed, and that the only method described to date for polyurea-based capsules without added polyamines is either the use of diisocyanates (due to their reactivity) as a necessary component or the absence of teachings on the use of triisocyanates, as the resulting capsules have subsequently been described as having low performance, particularly high oil leakage during storage.

[0035] Therefore, in its first embodiment, the present invention relates to a method for preparing a melamine-formaldehyde-free poly(urea-carbamate) core-shell microcapsule slurry, comprising the following steps:

[0036] 1) An oil containing an active ingredient, preferably a spice or flavoring, is mixed with at least one polyisocyanate having at least three isocyanate functional groups to form an oil phase, provided that the oil phase is substantially free of diisocyanates.

[0037] 2) Under acidic conditions, preferably at a pH below 4.5, an aqueous phase is prepared, comprising at least one anionic bio-derived polyol and a catalyst comprising a protic acid with a pKa below 4.5;

[0038] 3) The oil phase is added to the aqueous phase to form an oil-in-water dispersion;

[0039] 4) Perform a curing step to form a microcapsule slurry;

[0040] 5) Optionally, at least one cationic copolymer may be added to the capsule slurry;

[0041] The method is carried out without the addition of large amounts of amines or polyamines at any stage of the process.

[0042] Therefore, it was found that in the absence of diisocyanates and amines, under specific acid conditions, polyisocyanates containing at least three isocyanate functional groups and specific emulsifiers as bio-derived polyols can polymerize with sufficient efficiency to provide capsule walls with good performance.

[0043] In one step of the method, the oil phase is formed by mixing at least one hydrophobic active ingredient with at least one polyisocyanate, provided that the oil phase is substantially free of diisocyanates.

[0044] The hydrophobic active ingredients are preferably selected from the group consisting of seasonings, seasoning ingredients, spices, flavoring ingredients, nutritional products, cosmetics, insect repellents, biocidal active substances and mixtures thereof.

[0045] According to one specific implementation, the hydrophobic active ingredient comprises a mixture of fragrance and another ingredient selected from the group consisting of active substances in nutritional products, cosmetics, insect control agents and biocides.

[0046] According to one specific implementation plan, the hydrophobic active ingredient includes fragrance.

[0047] According to one specific implementation plan, the hydrophobic active ingredient is composed of fragrance.

[0048] By "fragrance" (or "fragrance oil"), it refers herein to an ingredient or composition that is liquid at about 20°C. According to any of the above embodiments, the fragrance oil may be a single fragrance ingredient or a mixture of multiple ingredients in the form of a fragrance composition. As a "fragrance ingredient," it refers herein to a compound whose primary purpose is to impart or modulate odor. In other words, to be considered a fragrance ingredient, it must be recognized by those skilled in the art as capable of at least imparting or altering the odor of a composition in an active or pleasant manner, and not merely having an odor. For the purposes of this invention, the fragrance oil also includes combinations of the fragrance ingredient with substances (e.g., fragrance precursors, emulsions, or dispersions) that together improve, enhance, or alter the delivery of the fragrance ingredient, and combinations that impart additional benefits beyond altering or imparting odor, such additional benefits as persistence, bursting, odor neutralization, antimicrobial effects, microbial stability, and insect control.

[0049] The nature and type of fragrance components present in the oil phase are not guaranteed to be described in greater detail here, as they are by no means exhaustive, and those skilled in the art can select them based on their common sense and according to the intended use or application and the desired sensory effect. Generally, these fragrance components belong to different chemical classifications, such as alcohols, aldehydes, ketones, esters, ethers, acetates, nitriles, terpenes, nitrogen- or sulfur-containing heterocyclic compounds, and essential oils, and the fragrance auxiliaries may be of natural or synthetic origin. In any case, many of these auxiliaries are listed in references such as S. Arctander's *Perfume and Flavor Chemicals*, 1969, Montclair, New Jersey, USA, or later editions thereof, or other works of a similar nature, as well as in the extensive patent literature in the field of fragrances. It is also understood that the components may also be compounds known to release various types of fragrance compounds in a controlled manner.

[0050] Fragrance ingredients can be dissolved in solvents currently used in the fragrance industry. The solvent is preferably not alcohol. Examples of such solvents are diethyl phthalate, isopropyl myristate, etc. (Rosin resin, available from Eastman), benzyl benzoate, ethyl citrate, limonene or other terpenes, or isoparaffins. Preferably, the solvent is highly hydrophobic and sterically hindered, for example... Or benzyl benzoate. Preferably, the fragrance contains less than 30% solvent. More preferably, the fragrance contains less than 20%, and even more preferably less than 10% solvent, all of which are defined by weight relative to the total weight of the fragrance. Most preferably, the fragrance is substantially solvent-free.

[0051] According to any embodiment of the invention, the hydrophobic active ingredient comprises about 10% to 60% w / w, or even 20% to 45% w / w, by weight, relative to the total weight of the dispersion obtained after step 3).

[0052] Suitable polyisocyanates used according to the present invention include aromatic polyisocyanates, aliphatic polyisocyanates, and mixtures thereof. The polyisocyanates contain at least three but may contain up to six, or even only four, isocyanate functional groups.

[0053] According to a specific implementation plan, triisocyanate (3 isocyanate functional groups) is used.

[0054] According to one embodiment, the polyisocyanate is an aromatic polyisocyanate. The term "aromatic polyisocyanate" herein includes any polyisocyanate containing an aromatic moiety. Preferably, it contains a phenyl, toluyl, xylyl, naphthyl, or diphenyl moiety, more preferably a toluyl or xylylyl moiety. Preferred aromatic polyisocyanates are biuret, polyisocyanurates, and trimethylolpropane adducts of diisocyanates, more preferably containing one of the aforementioned specific aromatic moieties. More preferably, the aromatic polyisocyanate is a polyisocyanurate of toluene diisocyanate (available from Bayer under the trade name...). (purchased from RC), trimethylolpropane adduct of toluene diisocyanate (available from Bayer under trade name) L75), trimethylolpropane adduct of phenyl diisocyanate (available from Mitsui Chemicals under trade name) (Obtained from D-110N). In a most preferred embodiment, the aromatic polyisocyanate is a trimethylolpropane adduct of phenyl diisocyanate.

[0055] According to another embodiment, the polyisocyanate is an aliphatic polyisocyanate. The term "aliphatic polyisocyanate" is defined as a polyisocyanate that does not contain any aromatic moiety. Preferred aliphatic polyisocyanates are trimers of hexamethylene diisocyanate, trimers of isophorone diisocyanate, trimethylolpropane adducts of hexamethylene diisocyanate (available from Mitsui Chemicals), or biuret of hexamethylene diisocyanate (available from Bayer under the trade name). N 100 (purchased), wherein a more preferred biuret is hexamethylene diisocyanate.

[0056] According to another embodiment, the at least one polyisocyanate is a mixture of at least one aliphatic polyisocyanate and at least one aromatic polyisocyanate, both containing at least three isocyanate functional groups, such as a mixture of hexamethylene diisocyanate biuret and phenyl diisocyanate trimethylolpropane adduct, a mixture of hexamethylene diisocyanate biuret and toluene diisocyanate polyisocyanate, and a mixture of hexamethylene diisocyanate biuret and toluene diisocyanate trimethylolpropane adduct. Most preferably, it is a mixture of hexamethylene diisocyanate biuret and phenyl diisocyanate trimethylolpropane adduct. Preferably, when used in mixture form, the molar ratio between the aliphatic polyisocyanate and the aromatic polyisocyanate is 80:20 to 10:90.

[0057] According to one embodiment, at least one polyisocyanate used in the method of the present invention is present in an amount of 1 to 15%, preferably 2 to 8%, more preferably 2 to 6%, of the oil phase.

[0058] According to one implementation scheme, the oil phase is free of diisocyanates.

[0059] According to one specific implementation, the oil phase is essentially composed of polyisocyanates having at least three isocyanate functional groups and flavoring or seasoning oils.

[0060] In another step of the method according to the invention, an anionic bio-derived polyol and a protic acid with a pKa below 4.5 are mixed under acidic conditions to form an aqueous phase. According to a preferred embodiment, the pH of the aqueous phase is below 4.5.

[0061] According to one specific implementation scheme, the anionic bio-derived polyols are selected from lignin, lignin sulfate, carboxymethyl cellulose, sodium alginate, polygalacturonic acid, sodium dextran sulfate, and mixtures thereof.

[0062] According to one implementation scheme, the protic acid is selected from the group consisting of glyoxylic acid, citric acid, tartaric acid, fumaric acid, salicylic acid, sulfuric acid, phosphoric acid, nitric acid, formic acid, hydrochloric acid, malic acid, lactic acid, oxalic acid, and mixtures thereof.

[0063] According to a preferred embodiment, proton acids with a pKa below 4.5 are selected from the group consisting of glyoxylic acid, citric acid, tartaric acid, fumaric acid, salicylic acid, oxalic acid, malic acid, lactic acid, formic acid, and mixtures thereof. According to a specific embodiment, proton acids with a pKa below 4.5 are composed of glyoxylic acid.

[0064] According to one embodiment, the catalyst contains at least 50% protic acids with a pKa below 4.5.

[0065] According to one specific implementation, the catalyst consists of protic acids with pKa below 4.5.

[0066] According to one specific implementation plan, the catalyst does not contain metal salts, especially tin salts.

[0067] According to any of the above embodiments of the present invention, the dispersion comprises about 0.5% to 2.5% w / w of anionic bio-derived polyols, the percentages being expressed on a w / w basis relative to the total weight of the dispersion obtained after step 3).

[0068] According to one embodiment of the present invention, the aqueous phase is cured at 45–60°C for 1 to 4 hours.

[0069] In another step of the method of the present invention, the oil phase is then added to the aqueous phase to form a dispersion, wherein the average droplet size is preferably 1 to 1000 μm, more preferably 1 to 500 μm, and even more preferably 5 to 50 μm. This is followed by a curing step 4), which allows the product to be encapsulated in the form of a slurry or liquid dispersion. According to a preferred embodiment, this step is carried out at a temperature of 60 to 80°C, possibly under pressure, for 1 to 4 hours. More preferably, it is carried out at 50 to 90°C for 30 minutes to 4 hours.

[0070] According to one specific embodiment of the present invention, at the end of step 4), a polymer selected from cationic polymers and mixtures thereof may be added to the slurry of the present invention to form an outer coating of the microcapsules.

[0071] Cationic polymers are well known to those skilled in the art, and preferred cationic polymers have a cationic charge density of at least 0.5 meq / g, more preferably at least about 1.5 meq / g, but even more preferably less than about 7 meq / g, more preferably less than about 6.2 meq / g. The cationic charge density of the cationic polymer can be determined by the Kjeldahl method as described in the chemical tests for nitrogen determination in the United States Pharmacopeia. Preferred cationic polymers are selected from those containing primary, secondary, tertiary, and / or quaternary amine groups that can form part of the main polymer chain or can be supported by side substituents directly connected thereto. The weight-average molecular weight (Mw) of the cationic polymer is preferably from 10,000 to 3.5 M Daltons, more preferably from 50,000 to 1.5 M Daltons. According to one specific implementation, cationic polymers based on the following substances may be used: acrylamide, methacrylamide, N-vinylpyrrolidone, quaternized N,N-dimethylaminomethacrylate, diallyl dimethylammonium chloride, quaternized vinylimidazolium (3-methyl-1-vinyl-1H-imidazolium-3-onium chloride), vinylpyrrolidone, acrylamide propyltrimethylammonium chloride, cassia gum hydroxypropyltrimethylammonium chloride, guar gum hydroxypropyltrimethylammonium chloride, or polygalactomannan 2-hydroxypropyltrimethylammonium chloride ether, starch hydroxypropyltrimethylammonium chloride, and cellulose hydroxypropyltrimethylammonium chloride. Preferably, the copolymer is 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, cassia gum hydroxypropyltrimethylammonium chloride, guar gum hydroxypropyltrimethylammonium chloride, or polygalactomannan 2-hydroxypropyltrimethylammonium chloride ether, starch hydroxypropyltrimethylammonium chloride, and cellulose hydroxypropyltrimethylammonium chloride. Specific examples of commercially available products can be cited. SC60 (a cationic copolymer of acrylamide propyltrimethylammonium chloride and acrylamide, source: BASF) or Such as PQ 11N, FC 550, or Style (quaternized copolymers of polyquaternium-11 to 68 or vinylpyrrolidone, source: BASF), and more. (C13S or C17, source: Rhodia).

[0072] According to any of the above embodiments of the present invention, the amount of the polymer added is about 0% to 5% w / w, or even about 0.1% to 2% w / w, the percentage being expressed on a w / w basis relative to the total weight of the slurry obtained after step 4). Those skilled in the art will clearly understand that only a portion of the added polymer will be incorporated into / deposited onto the microcapsule shell.

[0073] Alternatively, in optional step 5), the slurry obtained by the above method can be dried, such as by spray drying, to provide microcapsules as is, i.e., in powder form. It should be understood that any standard method known to those skilled in the art for performing such drying is also applicable. In particular, the slurry may preferably be spray-dried in the presence of a polymer carrier material such as polyvinyl acetate, polyvinyl alcohol, dextrin, natural or modified starch, plant gum, pectin, xanthan gum, alginate, carrageenan, or cellulose derivatives to provide microcapsules in powder form.

[0074] The invention also aims to obtain melamine- and formaldehyde-free poly(urea-carbamate) microcapsules, comprising a core containing oil and a shell substantially composed of a polymerized polyisocyanate and an anionic bio-derived polyol, wherein the polymerized polyisocyanate is formed from at least one polyisocyanate containing at least three isocyanate functional groups. Despite the film-forming properties of polyisocyanates and despite the absence of any polyamines, the capsules of the present invention exhibit excellent performance in terms of stability and delivery of active ingredients in challenging media.

[0075] In this regard, it must be mentioned that while ideally microcapsules exhibit optimal stability—that is, the lowest possible leakage of active ingredient upon application—combined with optimal delivery performance, i.e., fragrance strength before and after application, the varying degrees of stability depending on the application can be very interesting. Slightly less stable capsules with higher odor performance can be very useful, and so can more stable capsules with slightly lower odor performance. The capsules of the present invention have a profile of fragrance leakage / odor performance that varies depending on the proportion of polyisocyanates and the nature of the fragrance oil. Those skilled in the art can select the optimal balance according to the needs of the application. The capsules according to the present invention have the added advantage of being free of melamine-formaldehyde.

[0076] Another object of the present invention is a flavoring composition comprising:

[0077] (i) Microcapsules as defined above, wherein the oil contains fragrance;

[0078] (ii) at least one ingredient selected from the group consisting of flavor carriers, flavor auxiliaries and mixtures thereof;

[0079] (iii) Optionally, at least one flavoring adjuvant.

[0080] As liquid fragrance carriers, emulsified systems, i.e., solvent and surfactant systems, or solvents commonly used in fragrances, can be listed as non-limiting examples. A detailed description of the properties and types of solvents commonly used in fragrances is impossible to exhaust. However, solvents such as dipropylene glycol, diethyl phthalate, isopropyl myristate, benzyl benzoate, 2-(2-ethoxyethoxy)-1-ethanol, or ethyl citrate, which are the most commonly used, can be listed as non-limiting examples. For compositions containing fragrance carriers and fragrance auxiliary ingredients, in addition to those previously specified, other suitable fragrance carriers may also be ethanol, water / ethanol mixtures, limonene or other terpenes, isoparaffins, such as those marketed under trademarks... (Source: Exxon Chemical) Those known to the public, or glycol ethers and glycol ether esters, such as those marketed under trademarks... (Source: DowChemical Company) Those that are well-known. By "fragrance adjuvant," it refers to a compound used in a fragrance preparation or composition to impart a pleasurable effect, and is not a microcapsule as defined above. In other words, to be considered a fragrance adjuvant, it must be recognized by those skilled in the art as capable of actively or pleasantly imparting or altering the odor of a composition, and not merely having an odor.

[0081] The nature and type of fragrance additives present in fragrance compositions are not guaranteed to be described in greater detail here, as they are by no means exhaustive, and those skilled in the art can select them based on their common sense and according to the intended use or application and the desired sensory effect. Generally, these fragrance additives belong to different chemical classifications, such as alcohols, aldehydes, ketones, esters, ethers, acetates, nitriles, terpenes, nitrogen- or sulfur-containing heterocyclic compounds, and essential oils, and said fragrance additives may be of natural or synthetic origin. In any case, many of these additives are listed in references such as S. Arctander's *Perfume and Flavor Chemicals*, 1969, Montclair, New Jersey, USA, or later editions thereof, or other works of a similar nature, as well as in the extensive patent literature in the field of fragrances. It is also understood that said additives may also be compounds known to release various types of fragrance compounds in a controlled manner.

[0082] The term "fragrance adjuvant" refers to ingredients that can impart additional benefits (such as color, specific lightfastness, chemical stability, etc.). A detailed description of the properties and types of adjuvants commonly used in fragrance bases is impossible to exhaust, but it must be mentioned that the ingredients are well known to those skilled in the art.

[0083] Preferably, the flavoring composition according to the invention comprises 0.1 to 30% by weight of microcapsules as defined above.

[0084] The microcapsules of this invention are advantageously applicable in many fields and in consumer products. The microcapsules can be used in liquid form for liquid consumer products and in powder form for powder consumer products.

[0085] Another object of the present invention is a liquid consumer product comprising:

[0086] a) At least one surfactant in an amount of 2 to 65% by weight relative to the total weight of the consumer product;

[0087] b) Water or a water-miscible hydrophilic organic solvent; and

[0088] c) Microcapsules as defined above,

[0089] d) Optionally, unpackaged spices.

[0090] Powdered consumer products containing the following ingredients are also for the purposes of this invention:

[0091] (a) at least one surfactant comprising 2 to 65% of the total weight of the consumer product;

[0092] (b) Microcapsules as defined above.

[0093] (c) Optionally, a fragrance powder different from the microcapsules defined above.

[0094] When the microcapsules comprise a fragrance oil-based core, the products of the present invention are particularly suitable for scented consumer products, such as those belonging to the category of fine fragrances or "functional" fragrances. Functional fragrances particularly include personal care products, including hair care, body cleansing, skin care, hygiene care, and household care products, including clothing care and air care. Therefore, another object of the present invention is a scented consumer product comprising, as a fragrance ingredient, microcapsules as defined above or a fragrance composition as defined above. The fragrance ingredient of the consumer product may be a combination of fragrance microcapsules as defined above and free or unencapsulated fragrance, as well as other types of fragrance microcapsules besides those disclosed herein.

[0095] In particular, another objective of this invention is to produce liquid consumer products containing the following components:

[0096] a) At least one surfactant in an amount of 2 to 65% by weight relative to the total weight of the consumer product;

[0097] b) Water or a water-miscible hydrophilic organic solvent; and

[0098] c) Fragrance compositions as defined above.

[0099] Powdered consumer products containing the following ingredients are also part of this invention:

[0100] (a) at least one surfactant comprising 2 to 65% by weight relative to the total weight of the consumer product; and

[0101] (b) Fragrance compositions as defined above.

[0102] Therefore, the microcapsules of the present invention can be added to flavored consumer products as is or as part of the flavoring composition of the present invention.

[0103] For clarity, it must be mentioned that "fragrant consumer product" refers to a consumer product intended to deliver the fragrance effect, among various benefits, to a surface (e.g., skin, hair, textiles, paper, or household surfaces) or air (air freshener, deodorizer, etc.) to which it is applied. In other words, the fragrant consumer product according to the invention is a processed product comprising a functional formulation (also referred to as a "base") and beneficial agents, wherein an effective amount of microcapsules according to the invention is contained.

[0104] The nature and type of other ingredients in flavored consumer products are not guaranteed to be described in greater detail here, and are by no means exhaustive; those skilled in the art can select them based on their general knowledge and the properties and desired effects of the product. Formulations of consumer products in which the microcapsules of the present invention can be incorporated can be found in a large body of literature relating to such products. These formulations are not guaranteed to be described in detail here, and are by no means exhaustive. Those skilled in the art of formulating such consumer products are fully capable of selecting suitable components based on their general knowledge and available literature.

[0105] Suitable, non-limiting examples of scented consumer products may include perfumes, such as fine perfumes, colognes, or aftershaves; body sprays; fabric care products, such as liquid or solid detergents, tablets and capsules, fabric softeners, dry sheets, fabric fresheners, ironing solutions, or bleach; personal care products, such as hair care products (e.g., shampoos, conditioners, coloring agents, or hairsprays), cosmetic preparations (e.g., cold creams, body lotions, or deodorants or antiperspirants), or skin care products (e.g., soaps, bath mousses, body washes). Wash, bath oil or shower gel, bath salts, or hygiene products; air care products, such as air fresheners or "ready-to-use" powdered air fresheners; or household care products, such as general cleaners, liquid or powder or tablet dishwashing products, toilet cleaners, or products for cleaning various surfaces, such as sprays and wipes for treating / renovating textiles or hard surfaces (floors, tiles, stone floors, etc.); hygiene products, such as sanitary napkins, diapers, toilet paper, etc.

[0106] Preferably, the consumer product contains 0.1 to 15% by weight, more preferably 0.2 to 5% by weight, of the microcapsules of the present invention, these percentages being defined by weight relative to the total weight of the consumer product. Of course, the above concentrations can be adjusted according to the desired beneficial effects in each product.

[0107] The capsules of the present invention have been shown to be particularly advantageously stable in consumer products containing large amounts of surfactants, and more particularly, they exhibit improved stability compared to capsules in which only one type of particles is used.

[0108] The invention will now be further described by way of examples. It should be understood that the claimed invention is not limited in any way to these examples.

[0109] Example

[0110] Example 1

[0111] Preparation of the microcapsules of the present invention using glyoxylic acid and carboxymethyl cellulose

[0112] Microcapsule A-1:

[0113] Ambergum TM A solution of 1221 (carboxymethyl cellulose, a trademark of Hercules Inc.) in water was added to a 100 mL beaker. The pH was adjusted to 3.73 with glyoxylic acid. The solution was kept at 25°C before preparing the emulsion. A solution of fragrance oil (Table 1) and polyisocyanate (see Table 2) was added to the beaker and sheared at 24,000 rpm for 2 minutes using UltraTurrax. The emulsion was transferred to a 250 mL reactor and heated at 45°C for 1 hour, then at 60°C for 1 hour, and finally at 80°C for 3 hours. The reaction mixture was cooled to room temperature (pH = 3.87).

[0114] Table 2 reports the relative proportions of the raw materials.

[0115] Table 1: Fragrance Oil Compositions

[0116]

[0117] a) Methyl 2,2-dimethyl-6-methyl-1-cyclohexanecarboxylate, Source: Firmenich SA, Geneva, Switzerland

[0118] b) 2-tert-butyl-1-cyclohexyl acetate, trademarked by International Flavors & Fragrances, USA.

[0119] c) 4-(1,1-dimethylethyl)-1-cyclohexyl acetate, source: Firmenich SA, Geneva, Switzerland

[0120] d)(2Z)-2-phenyl-2-hexenonitrile, Source: Firmenich SA, Geneva, Switzerland

[0121] Table 2 - Capsule Formulation

[0122] raw material Quantity (g) % (w / w) water margin margin <![CDATA[Carboxymethyl cellulose (Ambergum TM 1221, 4%)]]> 40.00 2.37 2-Oxoacetic acid (50%) 0.57 0.42 Spice oils (Table 1) 25.00 37.10 <![CDATA[Polyisocyanate 1) > 1.90 2.11 total 67.47 100.00

[0123] 1) D-110N (75%) – Trimethylolpropane adduct of diphenyl diisocyanate, trademark from: Mitsui Chemicals

[0124] Microcapsule B-1

[0125] Microcapsule B-1 was prepared according to the protocol described for microcapsule A-1. A solution of carboxymethyl cellulose and glyoxylic acid was heated at 45°C for 1 hour and then cooled to 25°C (final pH = 3.69) before preparing the emulsion.

[0126] Microcapsule C-1

[0127] Microcapsule C-1 was prepared according to the protocol described for microcapsule A-1. A solution of carboxymethyl cellulose and glyoxylic acid was heated at 45°C for 2 hours and then cooled to 25°C (final pH = 3.85) before preparing the emulsion.

[0128] Microcapsule D-1

[0129] Microcapsule D-1 was prepared according to the protocol described for microcapsule A-1. A solution of carboxymethyl cellulose and glyoxylic acid was heated at 60°C for 1 hour and cooled to 25°C (final pH = 3.82) before preparing the emulsion.

[0130] Microcapsule E-1

[0131] Microcapsule E-1 was prepared according to the protocol described for microcapsule A-1. A solution of carboxymethyl cellulose and glyoxylic acid was heated at 60°C for 2 hours and cooled to 25°C (final pH = 3.81) before preparing the emulsion.

[0132] Microcapsule F-1

[0133] Microcapsule F-1 was prepared according to the conditions described for microcapsule B-1. Regarding the raw materials, a solution of the fragrance oil was prepared using 2.28 g of polyisocyanate (with 20% more NCO groups).

[0134] Microcapsule G-1

[0135] Microcapsule G-1 was prepared according to the conditions described for microcapsule B-1. Regarding the raw materials, a solution of the fragrance oil was prepared using 1.52 g of polyisocyanate (minimum 20% NCO groups).

[0136] Microcapsule H-1

[0137] Microcapsule H-1 was prepared according to the conditions described for microcapsule B-1. Regarding the raw materials, the oil phase contained fragrance oil and, as a polyisocyanate, D-110N (trimethylolpropane adduct of phenyl diisocyanate, trademark from Mitsui Chemicals) (0.95g) and

[0138] A mixture of N100 (biuret of hexamethylene diisocyanate) (trademark from Bayer) (0.95 g, final pH = 3.90).

[0139] Microcapsule I-1 According to the microcapsule B-1 protocol, 50g of Ambergum was used. TM Microcapsules I-1 were prepared using 1221 (Hercules Inc.) solution (plus 25% CMC) and 0.79 g glyoxylic acid solution (pH = 3.80).

[0140] Microcapsule J-1 According to the microcapsule B-1 protocol, 60g of Ambergum was used. TM Microcapsules J-1 were prepared using 1221 (Hercules Inc.) solution (50% more CMC) and 0.89 g glyoxylic acid solution (pH = 3.80).

[0141] Example 2

[0142] Preparation of the capsules of the present invention using acids with pKa < 4.5

[0143] Microcapsule A-2

[0144] Ambergum TM A solution of 1221 (Hercules Inc.) in water was added to a 100 mL beaker. The pH was adjusted to 4.05 with an aqueous nitric acid solution. The solution was kept at 45°C for 1 hour, then cooled to 25°C. A solution of the fragrance oil and polyisocyanate (see Table 3) was added to the beaker, and the two phases were sheared using UltraTurrax at 24,000 rpm for 2 minutes. The emulsion was transferred to a 250 mL reactor and heated at 45°C for 1 hour, then at 60°C for 1 hour, and finally at 80°C for 3 hours. The reaction mixture was cooled to room temperature (pH = 4.01).

[0145] Table 3 - Capsule Formulation

[0146]

[0147] 1)Ambergum TM 1221, 4%, Source: Hercules Inc.

[0148] 2) D-110N (75%) – Trimethylolpropane adduct of diphenyl diisocyanate, trademark from: Mitsui Chemicals

[0149] Microcapsule B-2

[0150] Microcapsule B-2 was prepared according to the scheme described for microcapsule A-2, but with sulfuric acid instead of nitric acid (96%, 0.15 g, final pH = 3.94).

[0151] Microcapsule C-2

[0152] Microcapsule C-2 was prepared according to the scheme described for microcapsule A-2, but with formic acid (99%, 0.16 g, final pH = 3.92) used instead of nitric acid.

[0153] Microcapsule D-2

[0154] Microcapsule D-2 was prepared according to the scheme described for microcapsule A-2, but with hydrochloric acid aqueous solution (37%, 0.29 g, final pH = 3.76) instead of nitric acid.

[0155] Microcapsule E-2

[0156] According to the protocol described for microcapsule A-2, microcapsule E-2 was prepared in place of nitric acid in the presence of an aqueous solution of phosphoric acid (84%, 0.29 g, final pH = 4.04).

[0157] Microcapsule F-2

[0158] According to the protocol described for microcapsule A-2, microcapsule F-2 was prepared in place of nitric acid in the presence of an aqueous oxalic acid solution (0.1 M, 15.40 g, final pH = 4.03).

[0159] Microcapsule G-2

[0160] According to the protocol described for microcapsule A-2, microcapsule G-2 was prepared in place of nitric acid in the presence of citric acid monohydrate (99.5%, source: Acros organics, 0.35 g, final pH = 4.14).

[0161] Example 3

[0162] Preparation of capsules according to the present invention

[0163] Microcapsule A-3:

[0164] A solution of sodium alginate (Alfa Aesar) in water was added to a 100 mL beaker. The pH was adjusted to 3.79 using glyoxylic acid. The solution was kept at 25°C before preparing the emulsion. A solution of fragrance oil (Table 1) and polyisocyanate was added to the beaker and sheared at 24,000 rpm for 2 minutes using UltraTurrax. The emulsion was transferred to a 250 mL reactor and heated at 45°C for 1 hour, then at 60°C for 1 hour, and finally at 80°C for 3 hours. The reaction mixture was cooled to room temperature (pH = 3.79). Table 4 reports the relative proportions of the raw materials.

[0165] Table 4 - Capsule Formulation

[0166] raw material Quantity (g) % (w / w) water margin margin <![CDATA[Sodium alginate 1) > 40.00 2.37 2-Oxoacetic acid (50%) 0.45 0.33 Spice oils (Table 1) 25.00 37.12 <![CDATA[Polyisocyanate 2) > 1.90 2.12 total 67.35 100.00

[0167] 1) 4% aqueous solution, source: Alfa Aesar A18565, with extremely low viscosity.

[0168] 2) D-110N (75%) – Trimethylolpropane adduct of diphenyl diisocyanate, trademark: Mitsui Chemicals

[0169] Microcapsule B-3

[0170] Microcapsule B-3 was prepared in the presence of glyoxylic acid and sodium alginate solution according to the scheme described for microcapsule A-3, resulting in a low-viscosity aqueous solution (source: Alfa Aesar B25266, final pH = 3.84).

[0171] Microcapsule C-3

[0172] Microcapsule C-3 was prepared in the presence of a solution of glyoxylic acid and polygalacturonic acid (pectin, source: Sigma, P3889, CAS RN 25990-10-7, final pH = 2.21) according to the protocol described for microcapsule A-3.

[0173] Microcapsule D-3

[0174] Microcapsule D-3 was prepared in the presence of a solution of glyoxylic acid and polygalacturonic acid (pectin, source: Sigma, P3850, CAS RN 9049-37-0, final pH = 3.67) according to the protocol described for microcapsule A-3.

[0175] Microcapsule E-3

[0176] Microcapsule E-3 was prepared in the presence of glyoxylic acid and dextran sulfate sodium salt solution (source: Sigma, D6924, CAS RN 9011-18-1, final pH = 2.46) according to the scheme described for microcapsule A-3.

[0177] Microcapsule F-3

[0178] Microcapsule F-3 was prepared in the presence of glyoxylic acid and sodium dextran sulfate solution (source: Sigma, 51227, final pH = 3.77) according to the scheme described for microcapsule A-3.

[0179] Example 4

[0180] Preparation of capsules A-4 to E-4 containing cationic copolymers

[0181] General Program

[0182] Ambergum TM A solution of 1221 (Hercules Inc.) in water (4 wt%, 40 g) was added to a 100 mL beaker (Table 5). The pH was adjusted to 3.80 with an aqueous glyoxylic acid solution (50 wt%, 0.55 g). The solution was kept at 45°C for 1 hour, then cooled to 25°C. The fragrance oil (Table 1) (25.00 g), A+ (oil-soluble UVA filter, Bayer) (1.25g) and polyisocyanate- A solution of 1.90 g of D-110N (75%) (trimethylolpropane adduct of phenyl diisocyanate, trademark from Mitsui Chemicals) was added to a beaker, and the two phases were sheared with UltraTurrax at 24000 rpm for 2 minutes (pH = 3.80). The emulsion was transferred to a 250 mL reactor and heated at 45 °C for 1 hour, then held at 60 °C for 1 hour, and finally held at 80 °C for 2 hours. Acrylamidopropyltrimethylammonium chloride and a cationic copolymer of acrylamide ( The aqueous solution of SC60 (source: BASF) (3 wt%, Table 5) was prepared and the dispersion was stirred at 80°C for 1 hour. Finally, the reaction mixture was cooled to room temperature (pH = 3.80).

[0183] Table 5

[0184] Microcapsules A-4 B-4 C-4 D-4 E-4 <![CDATA[Cationic copolymer 1) (g)]]> 5.0 10.50 17.00 25.00 35.00 <![CDATA[Cationic copolymer 1) (wt%)]]> 0.2 0.4 0.6 0.8 1.00

[0185] 1) A cationic copolymer of acrylamide propyltrimethylammonium chloride and acrylamide ( SC60 (Source: BASF)

[0186] Example 5

[0187] Preparation of capsules F-4 to R-4 using a mixture of cationic copolymers

[0188] General Program

[0189] Capsules were prepared according to the scheme described in Capsule A-4. A cationic copolymer of acrylamide propyltrimethylammonium chloride and acrylamide ( An aqueous solution of SC60 (source: BASF) (3 wt%, 20 g) and a mixture of the second copolymer (1 wt%, Table 6) were added together, and the dispersion was stirred at 80 °C for 1 hour. Finally, the reaction mixture was cooled to room temperature (pH = 3.80).

[0190] Table 6

[0191] Microcapsules copolymer Solution (g) Concentration (wt%) F-4 Jaguar C13S 11.00 0.1 G-4 Jaguar C17AD 11.00 0.1 H-4 Tinocare PQ760A 22.00 0.2 J-4 Luviquat FC550 11.00 0.1 K-4 Luviquat FC370 11.00 0.1 L-4 Luviquat Style 11.00 0.1 M-4 Luviquat Excellence 22.00 0.2 N-4 N-Hance SP100 11.00 0.1 O-4 Polyquaternium 550 11.00 0.1 P-4 Polyquaternium 550 60.00 0.4 Q-4 Mirustyle CP 11.00 0.1 R-4 Mirustyle MFP 11.00 0.1

[0192] Example 6

[0193] Preparation of microcapsules using glyoxylic acid, acetic acid, and carboxymethyl cellulose

[0194] Microcapsule B-6

[0195] Carboxymethyl cellulose (Ambergum) TM 1221; Hercules Inc.) The solution in water was added to a 100 mL beaker. 50 wt% and 50 wt% solutions of acetic acid and glyoxylic acid were prepared separately. The pH of the aqueous phase was adjusted to 3.80 (1.06 g) using this solution. The carboxymethyl cellulose and acid solution was heated at 45 °C for 1 hour and cooled to 25 °C before preparing the emulsion. The fragrance oil and polyisocyanate solution (Table 7) was added to the beaker and sheared at 24000 rpm for 2 minutes using UltraTurrax. The emulsion was transferred to a 250 mL reactor and heated at 45 °C for 1 hour, then at 60 °C for 1 hour, and finally at 80 °C for 3 hours. The reaction mixture was cooled to room temperature (pH = 3.86).

[0196] Table 7

[0197] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 2.36 Acetic acid and glyoxylic acid (50%) 50 / 50 w / w 0.85 0.94 Spice oils (Table 1) 25.00 36.90 <![CDATA[Polyisocyanate 2) > 1.90 2.10 water margin 57.70 total 67.75 100.00

[0198] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0199] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0200] Microcapsule C-6

[0201] According to the protocol for microcapsule B-6, microcapsule C-6 was prepared with 25 wt% and 75 wt% acetic acid and glyoxylic acid (pH = 3.67), respectively.

[0202] Table 8

[0203] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 2.36 Acetic acid and glyoxylic acid (50%) 25 / 75 w / w 0.64 0.59 Spice oils (Table 1) 25.00 37.02 <![CDATA[Polyisocyanate 2) > 1.90 2.11 water margin 57.91 total 67.54 100.00

[0204] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0205] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0206] Microcapsule E-6

[0207] According to the protocol for microcapsule B-6, microcapsules E-6 were prepared with 10 wt% and 90 wt% acetic acid and glyoxylic acid (pH = 3.67), respectively.

[0208] Table 9

[0209] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 2.37 Acetic acid and glyoxylic acid (50%) 10 / 90 w / w 0.68 0.45 Spice oils (Table 1) 25.00 37.00 <![CDATA[Polyisocyanate 2) > 1.90 2.11 water margin 58.07 total 67.58 100.00

[0210] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0211] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0212] Microcapsule F-6

[0213] According to the protocol for microcapsule E-6, microcapsules F-6 were prepared using 50g of carboxymethyl cellulose solution.

[0214] Table 10

[0215] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 50.00 2.57 Acetic acid and glyoxylic acid (50%) 10 / 90 w / w 0.85 0.49 Spice oils (Table 1) 25.00 32.15 <![CDATA[Polyisocyanate 2) > 1.90 1.83 water margin 62.96 total 77.75 100.00

[0216] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0217] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0218] Microcapsule G-6

[0219] According to the protocol for microcapsule E-6, microcapsules G-6 were prepared using 60g of carboxymethyl cellulose solution.

[0220] Table 11

[0221] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 60.00 2.76 Acetic acid and glyoxylic acid (50%) 10 / 90 w / w 0.99 0.51 Spice oils (Table 1) 25.00 28.77 <![CDATA[Polyisocyanate 2) > 1.90 1.64 water margin 66.32 total 86.89 100.00

[0222] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0223] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0224] Example 7

[0225] Preparation of microcapsules using acetic acid and carboxymethyl cellulose

[0226] Comparison of microcapsules A-7

[0227] Carboxymethyl cellulose (Ambergum) TM 1221; Hercules Inc.) The solution in water was added to a 100 mL beaker. The pH was adjusted to 4.01 with acetic acid. The solution was kept at room temperature before preparing the emulsion. The solution of fragrance oil and polyisocyanate was added to the beaker and sheared at 24,000 rpm for 2 minutes using UltraTurrax. The emulsion was transferred to a 250 mL reactor and heated at 45°C for 1 hour, then at 60°C for 1 hour, and finally at 80°C for 3 hours. The reaction mixture was cooled to room temperature (pH = 4.03).

[0228] Table 12

[0229] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 2.37 Acetic acid 0.70 1.04 Spice oils (Table 1) 25.00 36.98 <![CDATA[Polyisocyanate 2) > 1.90 2.11 water margin 57.50 total 67.6 100.00

[0230] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0231] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0232] Comparison of microcapsule B-7

[0233] Comparative microcapsule B-7 was prepared according to the same protocol as comparative microcapsule A-7. A solution of carboxymethyl cellulose and acetic acid was heated at 45°C for 1 hour and then cooled to room temperature (final pH = 3.95) before preparing the emulsion.

[0234] Comparison of microcapsule C-7

[0235] Comparative microcapsule C-7 was prepared according to the same protocol as comparative microcapsule B-7. A solution of carboxymethyl cellulose and acetic acid was heated at 45°C for 2 hours (final pH = 3.99) before emulsion preparation.

[0236] Comparison of microcapsule D-7

[0237] Comparative microcapsules D-7 were prepared according to the same protocol as comparative microcapsules B-7. A solution of carboxymethyl cellulose and acetic acid was heated at 60°C for 1 hour (final pH = 3.99) before emulsion preparation.

[0238] Comparison of microcapsules E-7

[0239] Comparative microcapsules E-7 were prepared according to the same protocol as comparative microcapsules B-7. A solution of carboxymethyl cellulose and acetic acid was heated at 60°C for 2 hours prior to emulsion preparation (final pH = 3.91).

[0240] Comparison with microcapsule F-7

[0241] Comparative microcapsule F-7 was prepared according to the same scheme as comparative microcapsule A-7. A fragrance oil solution was prepared using 2.28 g of polyisocyanate (containing 20% ​​more NCO groups).

[0242] Comparison of microcapsule G-7

[0243] Based on the scheme of comparative microcapsule F-7, comparative microcapsule G-7 was prepared using 1.52 g of polyisocyanate (with 20% less NCO groups).

[0244] Comparison of microcapsules H-7

[0245] Carboxymethyl cellulose (Ambergum) TM1221; Hercules Inc.) The solution in water was added to a 100 mL beaker. The pH was adjusted to 4.01 with acetic acid. The carboxymethyl cellulose and acetic acid solution was heated at 45°C for 1 hour and cooled to 25°C before preparing the emulsion. The fragrance oil and polyisocyanate solution (Table 13) were added to the beaker and sheared at 24,000 rpm for 2 minutes using UltraTurrax. The emulsion was transferred to a 250 mL reactor and heated at 45°C for 1 hour, then at 60°C for 1 hour, and finally at 80°C for 3 hours. The reaction mixture was cooled to room temperature (pH = 3.97).

[0246] Table 13 - Capsule Formulation

[0247] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 2.37 Acetic acid 0.70 1.04 Spice oils (Table 1) 25.00 36.98 <![CDATA[Polyisocyanate 1 2) > 1.90 1.90 <![CDATA[Polyisocyanate 2 3) > 0.19 0.28 water margin 57.43 total 67.6 100.00

[0248] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0249] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0250] 3) Biuret of hexamethylene diisocyanate (Source: Bayer)

[0251] Comparison of microcapsule I-7

[0252] Based on the scheme of comparative microcapsule H-7, comparative microcapsule I-7 was prepared using a solution of fragrance oil and 0.95 g of polyisocyanate (Table 14) (pH = 3.77).

[0253] Table 14 - Capsule Formulation

[0254] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 2.37 Acetic acid 0.70 1.04 Spice oils (Table 1) 25.00 36.98 <![CDATA[Polyisocyanate 1 2) > 0.95 1.05 <![CDATA[Polyisocyanate 2 3) > 0.95 1.41 water margin 57.15 total 67.6 100.00

[0255] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0256] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0257] 3) Biuret of hexamethylene diisocyanate (Source: Bayer)

[0258] Example 8

[0259] Preparation of microcapsules for body care applications

[0260] General Solution

[0261] Carboxymethyl cellulose (Ambergum) TM 1221; Hercules Inc.) The solution in water was added to a 100 mL beaker. The pH was adjusted to 3.82 with glyoxylic acid. The solution was kept at 25°C before preparing the emulsion. The solution of fragrance oil (Table 15) and polyisocyanate was added to the beaker and sheared at 24,000 rpm for 2 minutes using UltraTurrax. The emulsion was transferred to a 250 mL reactor and heated at 45°C for 1 hour, then at 60°C for 1 hour, and finally at 80°C for 2 hours. The cationic polymer solution was added, and the dispersion was stirred at 80°C for another 1 hour. The reaction mixture was cooled to room temperature (pH = 3.94).

[0262] Table 15: Fragrance oil composition in the capsules of Example 7

[0263]

[0264] 1) Source: Firmenich SA, Geneva, Switzerland

[0265] 2) Methyl dihydrojasmonic acid; Source and trademark: Firmenich SA, Geneva, Switzerland

[0266] 3) 1-(octahydro-2,3,8,8-tetramethyl-2-naphthyl)-1-ethyl ketone; Source: International Flavors & Fragrances, USA

[0267] Microcapsule A-8

[0268] The capsules of the present invention were prepared using 0.80% cationic copolymer.

[0269] Table 16 - Capsule Formulation

[0270] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 1.74 Glyoxylic acid (50%) 0.51 0.28 Spice oils (Table 15) 25.00 27.20 <![CDATA[Polyisocyanate 2) > 1.90 1.55 <![CDATA[Cationic copolymer 3) > 24.50 0.80 water margin 68.43 total 91.91 100.00

[0271] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0272] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0273] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0274] Microcapsule B-8 The capsules of the present invention were prepared using a mixture of cationic copolymers (Table 17).

[0275] Table 17 - Capsule Formulation

[0276] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 1.62 Glyoxylic acid (50%) 0.57 0.29 Spice oils (Table 15) 25.00 25.39 <![CDATA[Polyisocyanate 2) > 1.90 1.45 <![CDATA[Cationic copolymer 1 3) > 20.00 0.61 <![CDATA[Cationic copolymer 1 4) > 11.00 0.11 water margin 70.53 total 98.47 100.00

[0277] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0278] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0279] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0280] 4) Guar gum hydroxypropyltrimethylammonium chloride; 1% solution; Bayer

[0281] Microcapsule C-8

[0282] The capsules of the present invention were prepared using 0.40% cationic polymer.

[0283] Table 18 - Capsule Formulation

[0284] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 2.05 Glyoxylic acid (50%) 0.57 0.37 Spice oils (Table 15) 25.00 32.06 <![CDATA[Polyisocyanate 2) > 1.90 1.83 <![CDATA[Cationic polymer 3) > 10.50 0.40 water margin 63.29 total 98.47 100.00

[0285] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0286] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0287] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0288] Microcapsule D-8

[0289] The capsules of the present invention were prepared using a mixture of two cationic copolymers.

[0290] Table 19 - Capsule Formulation

[0291] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 1.62 Glyoxylic acid (50%) 0.57 0.29 Spice oils (Table 15) 25.00 25.39 <![CDATA[Polyisocyanate 2) > 1.90 1.45 <![CDATA[Cationic polymer 1 3) > 20.00 0.61 <![CDATA[Cationic polymer 2 4) > 11.00 0.11 water margin 70.53 total 98.47 100.00

[0292] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0293] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0294] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0295] 4) C17, Trademark: Rhodia (Guar Hydroxypropyl Trimethylammonium Chloride)

[0296] Microcapsule E-8

[0297] The capsules of the present invention are prepared using a mixture of cationic polymers.

[0298] Table 20 - Capsule Formulation

[0299] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 1.46 Glyoxylic acid (50%) 0.57 0.26 Spice oils (Table 15) 25.00 22.84 <![CDATA[Polyisocyanate 2) > 1.90 1.30 <![CDATA[Cationic polymer 1 3) > 20.00 0.55 <![CDATA[Cationic polymer 2 4) > 22.00 0.20 water margin 73.39 total 109.47 100.00

[0300] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0301] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0302] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0303] 4) Tinocare PQ 760A: Source and Trademark: BASF (acrylamide / diallyldimethylammonium chloride and acrylamide-propyltrimethylammonium chloride / acrylamide copolymer), 1% aqueous solution

[0304] Microcapsule F-8

[0305] The capsules of the present invention are prepared using a mixture of cationic polymers.

[0306] Table 21 - Capsule Formulation

[0307] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 1.62 Glyoxylic acid (50%) 0.57 0.29 Spice oils (Table 15) 25.00 25.39 <![CDATA[Polyisocyanate 2) > 1.90 1.45 <![CDATA[Cationic polymer 1 3) > 20.00 0.61 <![CDATA[Cationic polymer 2 4) > 11.00 0.11 water margin 70.53 total 98.47 100.00

[0308] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0309] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0310] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0311] 4) PQ11: Source and Trademark: BASF (1-vinylpyrrolidone-2-one / 2-(acryloyloxy)-N-ethyl-N,N-dimethylethyl-1-aminoethyl sulfate copolymer), 1% aqueous solution.

[0312] Microcapsule G-8

[0313] The capsules of the present invention are prepared using a mixture of cationic polymers.

[0314] Table 22 - Capsule Formulation

[0315] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 1.62 Glyoxylic acid (50%) 0.57 0.29 Spice oils (Table 15) 25.00 25.39 <![CDATA[Polyisocyanate 2) > 1.90 1.45 <![CDATA[Cationic polymer 1 3) > 20.00 0.61 <![CDATA[Cationic polymer 2 4) > 11.00 0.11 water margin 70.53 total 98.47 100.00

[0316] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0317] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0318] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0319] 4) FC550: Source and Trademark: BASF (3-methyl-1-vinyl-1H-imidazolium-3-chloride / 1-vinylpyrrolidine-2-one copolymer), 1% aqueous solution

[0320] Microcapsule H-8

[0321] The capsules of the present invention are prepared using a mixture of cationic polymers.

[0322] Table 23 - Capsule Formulation

[0323] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 1.62 Glyoxylic acid (50%) 0.57 0.29 Spice oils (Table 15) 25.00 25.39 <![CDATA[Polyisocyanate 2) > 1.90 1.45 <![CDATA[Cationic polymer 1 3) > 20.00 0.61 <![CDATA[Cationic polymer 2 4) > 11.00 0.11 water margin 70.53 total 98.47 100.00

[0324] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0325] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0326] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0327] 4) 550: Source and Trademark: Nalco (acrylamide / diallyldimethylammonium chloride copolymer), 1% aqueous solution

[0328] Microcapsule I-8

[0329] The capsules of the present invention were prepared using a mixture of cationic polymers.

[0330] Table 24 - Capsule Formulation

[0331] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 1.22 Glyoxylic acid (50%) 0.57 0.22 Spice oils (Table 15) 25.00 19.02 <![CDATA[Polyisocyanate 2) > 1.90 1.08 <![CDATA[Cationic polymer 1 3) > 20.00 0.46 <![CDATA[Cationic polymer 2 4) > 44.00 0.33 water margin 77.67 total 131.47 100.00

[0332] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0333] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0334] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0335] 4) 550: Source and Trademark: Nalco (acrylamide / diallyldimethylammonium chloride copolymer), 1% aqueous solution

[0336] Microcapsule J-8

[0337] The capsules of the present invention are prepared using a mixture of cationic polymers.

[0338] Table 25 - Capsule Formulation

[0339]

[0340] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0341] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0342] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0343] 4) Style: Source and Trademark: BASF (3-methyl-1-vinyl-1H-imidazolium-3-chloride / 1-vinylpyrrolidone-2-one copolymer), 1% aqueous solution

[0344] Microcapsule K-8

[0345] The capsules of the present invention are prepared using a mixture of cationic polymers.

[0346] Table 26 - Capsule Formulation

[0347] raw material Quantity (g) % (w / w) Carboxymethyl cellulose 1) 40.00 1.46 Glyoxylic acid (50%) 0.57 0.26 Spice oils (Table 15) 25.00 22.84 <![CDATA[Polyisocyanate 2) > 1.90 1.30 <![CDATA[Cationic polymer 1 3) > 20.00 0.55 <![CDATA[Cationic polymer 2 4) > 22.00 0.20 water margin 73.39 total 109.47 100.00

[0348] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0349] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0350] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0351] 4) Excellence: Source and Trademark: BASF (3-methyl-1-vinyl-1H-imidazolium-3-chloride / 1-vinylpyrrolidone-2-one copolymer), 1% aqueous solution

[0352] Microcapsule L-8

[0353] The capsules of this invention were prepared using phosphoric acid and cationic polymers.

[0354] Table 27 - Capsule Formulation

[0355] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 1.58 Phosphoric acid (84%) 0.29 0.24 Spice oils (Table 15) 25.00 24.71 <![CDATA[Polyisocyanate 2) > 1.90 1.41 <![CDATA[Cationic polymer 3) > 34.00 1.01 water margin 71.05 total 101.19 100.00

[0356] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0357] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0358] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0359] Microcapsule M-8

[0360] The capsules of this invention were prepared using oxalic acid and cationic polymers.

[0361] Table 28 - Capsule Formulation

[0362]

[0363]

[0364] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0365] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0366] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0367] Microcapsule N-8

[0368] The capsules of this invention are prepared using citric acid and cationic polymers.

[0369] Table 29 - Capsule Formulation

[0370] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 1.58 Citric acid monohydrate (99.5%) 0.35 0.34 Spice oils (Table 15) 25.00 24.69 <![CDATA[Polyisocyanate 2) > 1.90 1.41 <![CDATA[Cationic polymer 3) > 34.00 1.01 water margin 70.97 total 101.25 100.00

[0371] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0372] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0373] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0374] Microcapsule O-8

[0375] The capsules of this invention were prepared using malic acid and cationic polymers.

[0376] Table 30 - Capsule Formulation

[0377] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 1.58 DL-malic acid 0.34 0.34 Spice oils (Table 15) 25.00 24.69 <![CDATA[Polyisocyanate 2) > 1.90 1.41 <![CDATA[Cationic polymer 3) > 34.00 1.01 water margin 70.97 total 101.24 100.00

[0378] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0379] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0380] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0381] Microcapsule P-8 The capsules of this invention were prepared using lactic acid and cationic polymers.

[0382] Table 31 - Capsule Formulation

[0383] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 1.58 L-lactic acid (90%) 0.38 0.34 Spice oils (Table 15) 25.00 24.68 <![CDATA[Polyisocyanate 2) > 1.90 1.41 <![CDATA[Cationic polymer 3) > 34.00 1.01 water margin 70.98 total 101.28 100.00

[0384] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0385] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0386] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0387] Microcapsule Q-8

[0388] The capsules of this invention were prepared using glyoxylic acid and cationic polymers.

[0389] Table 32 - Capsule Formulation

[0390] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 1.58 Glyoxylic acid (50%) 0.51 0.25 Spice oils (Table 15) 25.00 24.65 <![CDATA[Polyisocyanate 2) > 1.90 1.41 <![CDATA[Cationic polymer 3) > 34.00 1.01 water margin 71.10 total 101.41 100.00

[0391] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0392] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0393] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0394] Microcapsule R-8

[0395] The capsules of this invention are prepared using formic acid and cationic polymers.

[0396] Table 33 - Capsule Formulation

[0397] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 1.58 Formic acid (99%) 0.16 0.16 Spice oils (Table 15) 25.00 24.74 <![CDATA[Polyisocyanate 2) > 1.90 1.41 <![CDATA[Cationic polymer 3) > 34.00 1.01 water margin 71.10 total 101.06 100.00

[0398] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0399] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0400] 3) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0401] Example 9

[0402] AP ball bearing stability

[0403] Preparation of AP Roll-on Base Material

[0404] A mixture of BRIJ 72 (3.25 g, Croda, UK), BRIJ 721 (0.75 g, Croda, UK), and ARLAMOL E (4.00 g, Croda, UK) (preheated to 75°C) was added to water (51.00 g) with stirring. The mixture was homogenized for 10 minutes and then cooled to room temperature with stirring. LOCRON L (40.00 g, Clariant, Switzerland) was slowly added at 45°C, while the mixture was kept at room temperature. The capsule dispersion of the present invention (approximately 2.60 g) was added at 35°C to obtain a white liquid emulsion with an encapsulated fragrance oil concentration of 1%, a neutral odor (pH 4.2–4.7), and a viscosity of 1000–2500 cPs (measured 24–48 hours after production).

[0405] Table 34: Composition of AP Rollerball Base Material

[0406] raw material Quantity (g) % (w / w) BRIJ 72 3.25 3.17 BRIJ 721 0.75 0.73 ARLAMOL E 4.00 3.90 water 51.00 50.70 LOCRON L 40.00 39.00 Capsule dispersion 2.60 2.53 total 102.6 100

[0407] Spice leakage measurement

[0408] A 1 g sample of AP roll-on base material was introduced into a GC vial capped with a septum. The vial was stabilized at 65°C for 5 minutes with stirring. Sampling was performed for 10 minutes using an SPME fiber assembly with an 85 μm polyacrylate coating. The amount of fragrance leakage from the microcapsules was measured by gas chromatography (GC) using a GC system 6890N equipped with a 5973 mass spectrometer detector (Agilent Technologies, USA) and a DB-1MS column (30 m, id 0.25 mm, film thickness 0.25 μm). Volatiles were analyzed by GC at 60°C for 2 minutes, followed by analysis at 7°C for 1 minute. -1 Heating to 250°C, total running time was 29 minutes. Helium was used as the flowing gas phase (1.2 mL / min). -1 (Pressure 80.5 kPa, no splitting). Calibration curve measured using free fragrance oil.

[0409] Table 35

[0410]

[0411]

[0412] These results clearly demonstrate that the presence of at least one protic acid with a pKa below 4.5 prevents oil leakage from the microcapsules.

[0413] Example 10

[0414] Deposition on hair

[0415] Preparation of application base material

[0416] Table 36: Composition of Shampoo Base

[0417]

[0418]

[0419] 1) Ucare TM Polymer JR-400 (Source: Noveon)

[0420] Deposition measurement scheme

[0421] 1) Moisten the micro-hair sample (500mg) with tap water (40mL) at 37°C using a syringe, and then squeeze once.

[0422] 2) Pre-treat the wet hair sample with unfragrant matrix (0.2 mL), pass it through horizontal friction 5 times, then pass it through vertical friction 5 times; then rinse it with tap water at 37℃ (100 mL), and finally squeeze it once.

[0423] 3) Apply the scented base (0.2 mL, added to a capsule to obtain 0.2 wt% fragrance in the base) to the hair sample and rub it through 10 times horizontally, then rub it through 10 times vertically.

[0424] 4) Use a separation funnel to add 37℃ (100mL) tap water to rinse the hair sample, 7cm away from the well opening, and gently shake 5 times.

[0425] 5) Cut the hair sample into 20 mL vials and dry at 65°C overnight. Determine hair quality.

[0426] 6) Add EtOH (5 mL) to the vial, sonicate for 15 minutes, then shake on a plate for 30 minutes and filter.

[0427] 7) The reference substance was dried at 65°C overnight; EtOH (5 mL) was added to a vial, sonicated for 15 minutes, shaken on a plate for 30 minutes, and then filtered.

[0428] 8) Quantitative analysis of Uvinul A plus by HPLC.

[0429] Table 37: Microcapsule deposition on hair

[0430] Microcapsules Oil deposition rate [wt%] A-4 16.8 B-4 24.0 C-4 21.3 D-4 23.7 E-4 33.2 F-4 22.3 G-4 13.5 H-4 23.3 J-4 30.5 K-4 12.0 L-4 26.1 M-4 28.7 N-4 26.9 O-4 18.5 P-4 17.5 Q-4 20.1 R-4 14.3

[0431] These data highlight that good deposition can be achieved using the microcapsules of the present invention.

[0432] Example 11

[0433] Preparation of shower gel base using capsules

[0434] The capsules of the present invention were dispersed in the shower gel base described in Table 37 to obtain a concentration of 0.25% encapsulated fragrance oil. The shower gel base and capsules were stored at 50°C for one week.

[0435] Table 38: Shower Gel Formulas

[0436]

[0437] Stability in shower gel applications

[0438] The shower gel base containing 1g of capsules was introduced into a 20mL vial hermetically sealed with a rubber diaphragm. The vial was stabilized at 65°C for 5 minutes. A solid-phase microextraction (SPME fiber assembly, 85μm polyacrylate coated) needle was introduced into the vial through the diaphragm and held above the shower gel for 10 minutes. The needle was then injected into a GC syringe equipped with a DB-1MS column (Source: Agilent, length 30m, inner diameter 25mm, film thickness 0.25μm). Helium flow rate was 1.2mL / min, pressure was 80.5kPa, and split ratio was 20. The oven temperature was 60°C, increased to 250°C at a rate of 7°C / min.

[0439] Table 39: Stability (1 week - 50℃)

[0440]

[0441]

[0442] Capsules prepared with glyoxylic acid or stronger acids are stable in shower gel bases.

[0443] Example 12

[0444] Shampoo containing microcapsules prepared according to the method of the present invention

[0445] Preparation of microcapsules for shampoo applications

[0446] Microcapsule A9:

[0447] Ambergum TMA solution of 1221 (carboxymethyl cellulose, a trademark of Hercules Inc.) in water was added to a 100 mL beaker. The pH was adjusted to 3.89 with glyoxylic acid. The solution was kept at 25°C before preparing the emulsion. A solution of fragrance oil (see Table 40) and polyisocyanate (see Table 2) was added to the beaker and sheared at 24,000 rpm for 2 minutes using UltraTurrax. The emulsion was transferred to a 250 mL reactor and heated at 45°C for 1 hour, then at 60°C for 1 hour, and finally at 80°C for 2 hours. The cationic copolymer solution (Table 41) was added and the reaction was stirred at 80°C for 1 hour. Finally, the reaction mixture was cooled to room temperature (pH = 3.90).

[0448] Table 40: Composition of Fragrance Oils

[0449] raw material Quantity (g) Amyl acetate 1 Pipol Acetate (Z)-3-hexen-1-ol 0.67 Isoamyl acetate 0.76 Hexyl acetate 0.28 Hexylcinnamaldehyde 9.63 2-Methylvalerate ethyl 1) 1.3 benzyl benzoate 1.63 Methyl butyrate 7.63 Ethyl hexanoate 0.13 Methyl cinnamate 0.19 Allyl cyclohexylpropionate 2.73 Damasne 0.2 δ-Damaconone 0.21 dodecyl lactone 0.22 <![CDATA[Floropal TM 2)]]> 0.54 <![CDATA[Galaxolide TM 3)]]> 20.08 2-Ethyl methylbutyrate 1.08 2-(2-(4-methyl-3-cyclohexen-1-yl)propyl)cyclopentanone (Nectalactone) 9.9 Ethyl octanoate 4.03 Hexyl salicylate 4.61 <![CDATA[Verdox TM 4)]]> 17.93 2,4-Dimethyl-3-cyclohexene-1-carboxaldehyde 5) 2.6 Isopropyl myristate 11.66

[0450] 1) Source: Firmenich SA, Geneva, Switzerland

[0451] 2) 2,4,6-Trimethyl-4-phenyl-1,3-dioxane, Source: Symrise

[0452] 3) 4,6,6,7,8,8-Hexamethyl-1,3,4,6,7,8-Hexahydrocyclopentadiene[g]isobenzopyran, Source: International Flavors & Fragrances, USA

[0453] 4) 2-tert-butyl-1-cyclohexyl acetate, Source: International Flavors & Fragrances, USA

[0454] 5) Source: Firmenich SA, Geneva, Switzerland

[0455] Table 41 - Capsule Formulation

[0456] raw material Quantity (g) % (w / w) water margin margin <![CDATA[Carboxymethyl cellulose (Ambergum TM 1221, 4%)]]> 40.00 1.58 2-Oxoacetic acid (50%) 0.51 0.25 Spice oil 25.00 24.65 <![CDATA[Polyisocyanate 1) > 1.90 1.41 <![CDATA[Cationic copolymer 2) > 34.00 1.01 total 101.41 100.00

[0457] 1) D-110N(75%) - Trimethylolpropane adduct of phenyl dimethyl diisocyanate, trademark: Mitsui Chemicals;

[0458] 2) SC60: Source and Trademark: Ciba (acrylamidopropyltrimethylammonium chloride / acrylamide copolymer), 3% aqueous solution

[0459] Microcapsule B9Microcapsule B9 was prepared according to the protocol described for microcapsule A9. Oxalic acid solution (15.40 g, 0.1 M aqueous solution, pH 4.04) was used instead of glyoxylic acid solution.

[0460] Microcapsule C9 Microcapsule C9 was prepared according to the protocol described for microcapsule A9. Citric acid (0.35 g, 99.5%, pH 4.08) was used instead of glyoxylic acid solution.

[0461] Microcapsule D9 Microcapsules D9 were prepared according to the protocol described for microcapsule A9. DL malic acid (0.34 g, pH 4.08) was used instead of glyoxylic acid solution.

[0462] Microcapsule E9 Microcapsules E9 were prepared according to the protocol described for microcapsule A9. Lactic acid solution (0.38 g, 90% aqueous solution, pH 4.08) was used instead of glyoxylic acid solution.

[0463] Microcapsule F9 Microcapsule F9 was prepared according to the protocol described for microcapsule A9. Phosphoric acid solution (0.29 g, 84% aqueous solution, pH 4.03) was used instead of glyoxylic acid solution.

[0464] Microcapsule G9 Microcapsule G9 was prepared according to the protocol described for microcapsule A9. Formic acid (0.16 g, pH 4.08) was used instead of glyoxylic acid solution.

[0465] Hair appearance

[0466] Preparation of application base material

[0467] Table 42: Composition of Shampoo Base

[0468] Element Composition [wt%] A Deionized water 44.9 <![CDATA[Quaternized hydroxyethyl cellulose 1) > 0.3 85% glycerol (Source: Schweizerhall) 1.0 Glydant (Source: Lonza) 0.2 B Texapon NSO IS (Source: Cognis) 28.0 Tego Betain F 50 (Source: Goldschmidt AG) 3.2 Amphotensid GB 2009 (Source: Zschimmer&Schwarz) 2.0 C Texapon NSO IS (Source: Cognis) 4.0 Monomuls 90L-12 (Source: Gruenau) 0.3 D Deionized water 1.0 NIPAGIN monosodium salt (Source: NIPA) 0.1 E 10% sodium chloride aqueous solution 15.0 total 100.0

[0469] 1) Ucare TM Polymer JR-400 (Source: Noveon)

[0470] Performance measurement scheme

[0471] The capsules were infused with fragrance at a dose equivalent to 0.2% of the shampoo base and soaked at room temperature for at least 24 hours and then at 45°C for one month. Two dry hair samples (10g, Kerling Int., catalog number: 826500, Euro-Natural hair) were moistened in warm water (approximately 37°C) for 30 seconds, then each 10g of hair was washed with 1g of shampoo for 30 seconds. Gently rubbed with fingers. The washed hair samples were rinsed in a 1L beaker pre-filled with warm water. They were immersed in the beaker three times (three times in, three times out). Then they were immersed in the beaker and moved slowly back and forth three times in each direction, and finally rinsed under running water (flow rate 4 L / min) for 30 seconds (15 seconds per side) without touching the sample at all.

[0472] Remove excess water by squeezing the sample from the top plastic section to the ends of the hair. Do not touch or squeeze the hair sample to remove excess water. Perform a second wash with 1 gram of shampoo for 30 seconds and repeat the rinsing procedure described above. Place the hair sample on a drying rack to air dry at room temperature for 24 hours.

[0473] Before combing, assess the fragrance intensity of the hair sample according to the following fragrance intensity ratings: 1 - Imperceptible, 2 - Slightly perceptible, 3 - Weak, 4 - Medium, 5 - Persistent, 6 - Strong, 7 - Very Strong. Comb the hair sample three times with the thin end of a comb. The fragrance intensity immediately after combing is assessed using the same rating. Once the hair sample has been touched, rubbed, or combed, it cannot be evaluated using the "pre-combing" step. Therefore, at least two sets of hair samples were prepared. One set was never combed and used only for the "pre-combing" step. The other set was combed by up to ten team members for the "post-combing" step. If more than ten team members are required, another set of hair samples is prepared for the "post-combing" step. Hands are protected with gloves throughout the washing process.

[0474] The results are shown in the table below.

[0475] Table 43: Performance of Microcapsules on Hair

[0476]

[0477] These embodiments highlight that the microcapsules of the present invention exhibit good olfactory performance even for aged samples.

[0478] Example 13

[0479] Fabric softener containing microcapsules prepared by the method of the present invention

[0480] Preparation of microcapsules

[0481] Microcapsule A10

[0482] Ambergum TM A solution of 1221 (carboxymethyl cellulose, a trademark of Hercules Inc.) in water was added to a 100 mL beaker. The pH was adjusted to 3.73 with glyoxylic acid. The solution was kept at 25°C before preparing the emulsion. A solution of fragrance oil (Table 44) and polyisocyanate (see Table 45) was added to the beaker and sheared at 24,000 rpm for 2 minutes using UltraTurrax. The emulsion was transferred to a 250 mL reactor and heated at 45°C for 1 hour, then at 60°C for 1 hour, and finally at 80°C for 3 hours. The reaction mixture was cooled to room temperature (pH = 3.87).

[0483] Table 44: Fragrance Oil Compositions

[0484]

[0485] 1) Source: Firmenich SA, Geneva, Switzerland

[0486] 2) 1,3-Benzadioxopenten-5-carboxaldehyde, Source: Firmenich SA, Geneva, Switzerland

[0487] 3) 1-(5,5-dimethyl-1-cyclohexen-1-yl)-4-penten-1-one, Source: Firmenich SA, Geneva, Switzerland

[0488] Table 45 - Capsule Formulation

[0489] raw material Quantity (g) % (w / w) water margin margin <![CDATA[Carboxymethyl cellulose (Ambergum TM 1221, 4%)]]> 40.00 2.37 2-Oxoacetic acid (50%) 0.57 0.42 Spice oils (Table 44) 25.00 37.10 <![CDATA[Polyisocyanate 1) > 1.90 2.11 total 67.47 100.00

[0490] 1) D-110N(75%) - Trimethylolpropane adduct of phenyl dimethyl diisocyanate, trademark from: Mitsui Chemicals

[0491] Comparison of microcapsule B10

[0492] Carboxymethyl cellulose (Ambergum) TM 1221; Hercules Inc.) The solution in water was added to a 100 mL beaker. The pH was adjusted to 4.01 with acetic acid. The solution was kept at room temperature before preparing the emulsion. The solution of fragrance oil and polyisocyanate was added to the beaker and sheared at 24,000 rpm for 2 minutes using UltraTurrax. The emulsion was transferred to a 250 mL reactor and heated at 45°C for 1 hour, then at 60°C for 1 hour, and finally at 80°C for 3 hours. The reaction mixture was cooled to room temperature (pH = 4.03).

[0493] Table 46: Capsule Formation

[0494] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 2.37 Acetic acid 0.70 1.04 Spice oils (Table 44) 25.00 36.98 <![CDATA[Polyisocyanate 2) > 1.90 2.11 water margin 57.50 total 67.6 100.00

[0495] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0496] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0497] softener ingredients

[0498] A concentrated, unfragrant fabric softener base was prepared by mixing the ingredients listed in Table 47 in the amounts shown. Percentages are defined by weight relative to the total weight of the unfragrant fabric softener base.

[0499] Table 47: Formulation of concentrated unscented fabric softener base (pH ~ 2.85)

[0500] Element ％ <![CDATA[Stepantex VL90 A Diester Quat 1) ]]> 16.50 <![CDATA[Proxel GXL 2) ]]> 0.04 <![CDATA[CaCl2 (10% aqueous solution)]]> 0.20 water 83.26

[0501] 1) Source: Stepan

[0502] 2) Source: Avecia

[0503] The softener was prepared by adding capsules A10 and control capsules B10, at a weight of 0.45% relative to the total weight of the softener, to the unscented softener base in Table 47 under gentle shaking.

[0504] Storage stability performance

[0505] The storage stability of capsule A10 (glyoxylic acid) in the above-mentioned fabric softener was evaluated after two weeks of storage at 43°C. The storage stability of the control capsule B10 (acetic acid) was also evaluated. The amount of fragrance leaked from the capsules over time was measured by solvent extraction and GC-MS analysis (see Table 44). The results are summarized in Table 48 below.

[0506] Table 48: Storage stability of capsules

[0507] After being stored in a softener at 43°C for 2 weeks, the percentage of fragrance leaking from the capsules was [percentage missing]. Comparison with capsule B10 (acetic acid) >90％ Capsule A10 (glyoxylic acid) 22％

[0508] The above results show that the microcapsules prepared by the method of the present invention have significantly higher stability than the comparative microcapsules.

[0509] Olfactory performance

[0510] Washing and rinsing protocol:

[0511] In a European washing machine (Miele Novotronic W300-33CH), using a short cycle, cotton towels (20 towels, 18cm x 18cm, approximately 30g each) were washed at 40°C with 30g of unscented detergent. After washing, they were rinsed at 900rpm with 12.7g of the aforementioned concentrated fabric softener, which had been stored at 43°C for two weeks. The towels were then air-dried for 24 hours and evaluated by a panel of 20 trained members. The members were asked to gently rub the fabric by hand and rate the odor intensity on a scale of 1 to 10, where 1 corresponds to no odor and 10 corresponds to a very strong odor.

[0512] result

[0513] The team members discovered:

[0514] 1 / For fresh products, after drying, fabrics washed and treated with capsule A10 of the present invention delivered a strong fragrance enhancement upon rubbing. Fabrics washed and treated with comparative capsule B10 delivered a stronger fragrance impact before rubbing but provided lower enhancement upon rubbing, indicating poorer stability of the capsules in the washing machine.

[0515] 2 / Using a softener aged at 43°C for 2 weeks, after drying, fabrics washed and treated with the capsules A10 of the present invention still provided a strong fragrance enhancement upon rubbing, only slightly reduced compared to fresh fabrics, and conformed to good analytical fragrance stability. On the other hand, fabrics washed and treated with the comparative capsules B10 delivered a stronger fragrance impact before rubbing but showed no enhancement upon rubbing, again fully consistent with the very poor stability of these capsules in the fabric softener base at 43°C.

[0516] Example 14

[0517] AP roll-on containing microcapsules prepared by the method of the present invention

[0518] Preparation of microcapsules for AP roll-on applications

[0519] Microcapsule A11

[0520] Ambergum TMA solution of 1221 (carboxymethyl cellulose, a trademark of Hercules Inc.) in water was added to a 100 mL beaker. The pH was adjusted to 3.82 with glyoxylic acid solution. This solution was kept at 25°C before preparing the emulsion. A solution of fragrance oil (see Table 49) and polyisocyanate (see Table 50) was added to the beaker and sheared at 24,000 rpm for 2 minutes using UltraTurrax. The emulsion was transferred to a 250 mL reactor and heated at 45°C for 1 hour, then at 60°C for 1 hour, and finally at 80°C for 2 hours. The cationic copolymer solution was added, and the reaction was stirred at 80°C for 1 hour. Finally, the reaction mixture was cooled to room temperature (pH = 3.96).

[0521] Table 49: Fragrance Oil Compositions

[0522]

[0523]

[0524] 1) Methyl dihydrojasmonic acid, Source: Firmenich SA, Geneva, Switzerland

[0525] 2) 1-(5,5-dimethyl-1-cyclohexen-1-yl)-4-penten-1-one, Firmenich SA, Geneva, Switzerland

[0526] Table 50 - Capsule Formulation

[0527] raw material Quantity (g) % (w / w) water margin margin <![CDATA[Carboxymethyl cellulose (Ambergum TM 1221, 4%)]]> 40.00 2.37 2-Oxoacetic acid (50%) 0.51 0.38 Spice oils (see Table 49) 25.00 37.09 <![CDATA[Polyisocyanate 1) > 1.90 2.11 total 67.41 100.00

[0528] 1) D-110N(75%) - Trimethylolpropane adduct of phenyl dimethyl diisocyanate, trademark from: Mitsui Chemicals

[0529] Microcapsule B11 Microcapsule B11 was prepared according to the protocol described for microcapsule A11. A solution of glyoxylic acid and carboxymethyl cellulose was heated to 60°C and maintained for 2 hours.

[0530] Microcapsule C11 Microcapsules C11 were prepared according to the scheme described for microcapsule A11. A mixture of acetic acid (0.12 g) and glyoxylic acid solution (50 wt%, 0.36 g) was used instead of the glyoxylic acid solution.

[0531] Microcapsule D11 Microcapsules D11 were prepared according to the protocol described for microcapsule A11. Citric acid (0.35 g) was used instead of glyoxylic acid solution.

[0532] Microcapsule E11Microcapsules E11 were prepared according to the protocol described for microcapsule A11. Phosphoric acid solution (84%, 0.29 g) was used instead of glyoxylic acid solution.

[0533] Comparison with microcapsule G11:

[0534] Carboxymethyl cellulose (Ambergum) TM 1221; Hercules Inc.) The solution in water was added to a 100 mL beaker. The pH was adjusted to 4.01 with acetic acid. The solution was kept at room temperature before preparing the emulsion. The solution of fragrance oil (see Table 49) and polyisocyanate was added to the beaker and sheared at 24,000 rpm for 2 minutes using UltraTurrax. The emulsion was transferred to a 250 mL reactor and heated at 45 °C for 1 hour, then at 60 °C for 1 hour, and finally at 80 °C for 3 hours. The reaction mixture was cooled to room temperature (pH = 4.03).

[0535] Table 51: Capsule Formation

[0536] raw material Quantity (g) % (w / w) <![CDATA[Carboxymethyl cellulose 1) > 40.00 2.37 Acetic acid 0.70 1.04 Spice oils (Table 49) 25.00 36.98 <![CDATA[Polyisocyanate 2) > 1.90 2.11 water margin 57.50 total 67.6 100.00

[0537] 1)Ambergum TM 1221, 4%; Hercules Inc.

[0538] 2) D-110N (75%) is a trademark of Mitsui Chemicals; a trimethylolpropane adduct of phenyl diisocyanate.

[0539] AP ball bearing stability

[0540] Preparation of AP Roll-on Base Material

[0541] A mixture of BRIJ 72 (3.25 g, Croda, UK), BRIJ 721 (0.75 g, Croda, UK), and ARLAMOL E (4.00 g, Croda, UK) (preheated to 75°C) was added to water (51.00 g) with stirring. The mixture was homogenized for 10 minutes and then cooled to room temperature with stirring. LOCRON L (40.00 g, Clariant, Switzerland) was slowly added at 45°C, while the mixture was kept at room temperature. Finally, the fragrance oil (1.00 g, Firmenich SA, Switzerland) or the capsule dispersion of the present invention (2.60 g) was added at 35°C to obtain a white liquid emulsion with a neutral odor (pH 4.2–4.7) and a viscosity of 1000–2500 cPs (measured 24–48 hours after production).

[0542] Preparation of AP roll-on ball applications

[0543] The capsule dispersion (0.55 g) was introduced into the AP roll-on base material UBK 99 032 (50 g, table) as described above. The base material and dispersion were stirred for 5 minutes at 500 rpm and room temperature using a dissolver stirrer (R-1303, IKA, Germany) and a top-mounted stirrer (Eurostar, IKA, Germany). The sample was stored at 25°C for two weeks.

[0544] Spice leakage measurement

[0545] A 1 g sample of AP roll-on base material was introduced into a GC vial capped with a septum. The vial was stabilized at 65°C for 5 minutes with stirring. Sampling was performed for 10 minutes using an SPME fiber assembly with an 85 μm polyacrylate coating. The amount of fragrance leakage from the microcapsules was measured by gas chromatography (GC) using a GC system 6890N equipped with a 5973 mass spectrometer detector (Agilent Technologies, USA) and a DB-1MS column (30 m, id 0.25 mm, film thickness 0.25 μm). Volatiles were analyzed by GC at 60°C for 2 minutes, followed by analysis at 7°C for 1 minute. -1 Heating to 250°C, total running time was 29 minutes. Helium was used as the flowing gas phase (1.2 mL / min). -1 (Pressure 80.5 kPa, no splitting). Calibration curve measured using free fragrance oil.

[0546] Table 51: Stability measurement of AP roll-on / roll-off base material at 45°C (one month at 45°C)

[0547] Microcapsules ％ Microcapsule A11 2.6 Microcapsule B11 1.1 Microcapsule C11 3.7 Microcapsule D11 1.8 Microcapsule E11 0.8 Comparison Capsule G11 44.9

[0548] The above results show that the microcapsules prepared by the method of the present invention have significantly higher stability than the comparative microcapsules.

Claims

1. A method for preparing a melamine-formaldehyde-free poly(urea-carbamate) core-shell microcapsule slurry, comprising the following steps: 1) An oil containing an active ingredient, preferably a fragrance, is mixed with at least one polyisocyanate having at least three isocyanate functional groups to form an oil phase, provided that the oil phase is substantially free of diisocyanates. 2) An aqueous phase is prepared under acidic conditions with a pH below 4.5, comprising at least one anionic bio-derived polyol and a catalyst containing a protic acid with a pKa below 4.5 and free of tin salts; 3) The oil phase is added to the aqueous phase to form an oil-in-water dispersion; 4) Perform a curing step to form a microcapsule slurry; 5) Optionally, at least one cationic copolymer may be added to the capsule slurry; The method is carried out without the addition of large amounts of amines or polyamines at any stage of the process. The characteristic feature is that the protic acid is selected from the group consisting of glyoxylic acid, tartaric acid, fumaric acid, salicylic acid, sulfuric acid, nitric acid, hydrochloric acid, malic acid, lactic acid, and mixtures thereof. The anionic bio-derived polyol was selected from the group consisting of lignin, lignin sulfate, carboxymethyl cellulose, sodium alginate, polygalacturonic acid, sodium dextran sulfate, and mixtures thereof, and The dispersion contains 0.5% to 2.5% w / w of the anionic bio-derived polyol, the percentage being expressed on a w / w basis relative to the total weight of the dispersion obtained after step 3).

2. The method according to claim 1, characterized in that... Step 2 also includes curing the aqueous phase at 45–60°C for 30 minutes to 2 hours.

3. The method according to claim 1 or 2, characterized in that... Step 4 consists of interfacial polymerization at 60–80°C for 1 to 4 hours.

4. The method according to any one of claims 1 to 3 further includes the step of drying the capsule slurry to obtain dried microcapsules.

5. The method according to any one of claims 1 to 4, characterized in that... The at least one polyisocyanate having at least three isocyanate functional groups is present in an amount of 1 to 15 wt% of the oil phase.

6. The method according to any one of claims 1 to 5, characterized in that... The at least one polyisocyanate having at least three isocyanate functional groups includes aromatic polyisocyanates.

7. The method according to any one of claims 1 to 6, characterized in that... The oil phase is essentially composed of spice or flavoring oil and at least one polyisocyanate having at least three isocyanate functional groups.

8. A melamine-formaldehyde-free poly(urea-carbamate) microcapsule, obtainable by the method of any one of claims 1 to 7, comprising a core and a shell, the core containing oil, the shell being substantially composed of a polymerized polyisocyanate and an anionic bio-derived polyol, the polymerized polyisocyanate being formed from at least one polyisocyanate containing at least three isocyanate functional groups.

9. A flavoring composition comprising: (i) the microcapsule as defined in claim 8, wherein the oil contains a fragrance; (ii) at least one ingredient selected from the group consisting of flavor carriers and flavor auxiliaries; and (iii) Optionally, at least one flavoring adjuvant.

10. A liquid consumption product comprising: a) At least one surfactant comprising 2 to 65% by weight of the total weight of the consumer product; b) Water or a water-miscible hydrophilic organic solvent; and c) The microcapsules as defined in claim 8 or the flavored composition as defined in claim 9.

11. The liquid consumption product according to claim 10, characterized in that, The product in question is a home care product or a personal care product.

12. The product according to claim 11, wherein it is in the form of a leave-in hair care product.

13. A powdered consumer product comprising: (a) at least one surfactant comprising 2 to 65% by weight relative to the total weight of the consumer product; and (b) The microcapsule as defined in claim 8 or the flavored composition as defined in claim 9.

Images