Encapsulated composition

Abstract

FIELD: chemistry.SUBSTANCE: encapsulated perfume composition, which is a core-shell microcapsule, in which the core-shell microcapsule contains a core with at least one perfume ingredient, and a first shell surrounding the core, where the first shell contains a polymer stabilizer, which is formed by combining a polymer surfactant with at least one dipodal aminosilane, in which the polymer surfactant contains anionic groups or groups that can form anions, and a second shell encapsulating the first shell, wherein said second shell is formed by reacting an alkylated polyfunctional amine or reacting a polyfunctional amine with an aldehyde or reacting a polyisocyanate with a polyfunctional amine, as well as a method for producing the encapsulated composition and a washable consumer product containing the encapsulated composition.EFFECT: improving the stability of encapsulated core-shell perfume compositions while maintaining the desired release profile during use.14 cl, 3 tbl, 7 ex

Description

[0001] The present invention relates to an encapsulated composition comprising at least one core-shell microcapsule. The invention also relates to a method for producing the encapsulated composition and the use of such a composition to improve the properties of perfumery and / or cosmetic ingredients in consumer products. Furthermore, the present invention relates to a polymeric stabilizer and the use of such a polymeric stabilizer in the encapsulation of perfumery and / or cosmetic ingredients.

[0002] The introduction of encapsulated functional materials into consumer products, such as household chemicals, personal care products, and fabric care products, is known. Functional materials include, for example, perfumes, cosmetic agents, pharmaceuticals, and substrate enhancers.

[0003] Microcapsules that are particularly suitable for delivering such functional materials are core-shell microcapsules, in which the core typically contains the functional material, and the shell is impermeable or partially impermeable to the functional material. Such microcapsules are typically used in aqueous environments, and the encapsulated ingredients are hydrophobic. A wide range of shell materials can be used, provided that the shell material is impermeable or partially impermeable to the encapsulated ingredient.

[0004] Among functional materials, perfume and / or cosmetic ingredients are encapsulated for a variety of reasons. Microcapsules can isolate and protect this type of material from external suspending environments, such as consumer product bases, where they may be incompatible or unstable. They are also used to facilitate the distribution of ingredients on substrates such as skin or hair, as well as fabrics or hard household surfaces in the case of perfume ingredients. They can act as a means of regulating the spatiotemporal release of the ingredient.

[0005] The prior art has proposed a wide variety of encapsulating media, as well as perfume and / or cosmetic ingredients suitable for the manufacture of encapsulated compositions. Such encapsulating media include synthetic resins such as polyamides, polyureas, polyurethanes, polyacrylates, melamine-derived resins, or mixtures thereof.

[0006] Regarding materials suitable for the core, in principle, all ingredients in the perfume and / or cosmetics palette can be incorporated to some degree into a core-shell microcapsule. However, it is generally accepted that certain physicochemical properties of an ingredient, primarily its clog P, will influence whether and to what extent it can be encapsulated, and once encapsulated, its ability to remain in the core without significant leakage during storage.

[0007] In the hands of a skilled formulator, thoughtful selection of both shell and core materials can produce microencapsulated compositions that are stable in many consumer products, allowing for controlled release of the fragrance and / or cosmetic substance over time. However, even when using proven shell chemistries in combination with a suitable core composition, the formulator faces a difficult compromise between ensuring, on the one hand, that the microcapsules are sufficiently robust to be stable and not leak during production and storage, and, on the other hand, that there is sufficient release of the core contents during use. Another problematic aspect is the undesirable side reactions of the shell-forming compounds with the materials to be encapsulated during capsule formation.

[0008] US 2014 / 0331414 A1 discloses microcapsules produced by emulsifying perfume oil in the presence of a polymeric surfactant and silanes. The advantage of this chemistry is that it occurs under mild reaction conditions, particularly because the silanes are relatively unreactive with the encapsulated substances. These resulting microcapsules exhibit good olfactory properties on wet fabrics but exhibit limited stability with respect to leakage of perfume ingredients into surfactant-containing product bases during long-term storage.

[0009] Therefore, the problem underlying the present invention is to overcome the aforementioned shortcomings of the prior art. Specifically, the problem underlying the present invention is to provide encapsulated compositions of the aforementioned type that exhibit increased stability during production and storage while maintaining the desired release profile during use. Furthermore, the compositions must be manufactured in a safe, reliable, and cost-effective manner.

[0010] These problems are solved by the present invention. In a first aspect, the present invention relates to an encapsulated composition comprising at least one core-shell microcapsule. The at least one core-shell microcapsule comprises a core containing at least one perfume and / or cosmetic ingredient, and a shell surrounding the core. The shell comprises a polymeric stabilizer, which is formed by combining a polymeric surfactant with at least one dipodal aminosilane.

[0011] The term "polymeric surfactant" refers to a polymer that has the ability to reduce the interfacial tension between the oil phase and the aqueous phase when dissolved in one or both phases. This ability to reduce interfacial tension is called "interfacial activity."

[0012] The term "dipodal aminosilane" refers to a molecule containing at least one amino group and two residues, each of which carries at least one alkoxysilane fragment.

[0013] The term "formed by combination" in the present invention means that a polymeric surfactant and at least one dipodal aminosilane are brought into contact with each other to form a polymeric stabilizer. Without being limited to any particular theory, such formation may result from interactions between the polymeric surfactant and the at least one dipodal aminosilane, such as dispersion forces, electrostatic forces, or hydrogen bonds. However, this term also includes a chemical reaction that forms covalent bonds.

[0014] In addressing the problems of the prior art, it was discovered that the polymer stabilizer is a factor that contributes to the balance between microcapsule stability against perfume leakage during storage and perfume release under use. In particular, the importance of providing additional stabilization of the oil-water interface was identified.

[0015] The polymer stabilizer helps provide a particularly stable platform onto which various shell chemistries are deposited around perfume oil droplets to form new encapsulated perfume compositions, giving the formulator ample opportunity to create microcapsules with additional functionality or desired properties.

[0016] In particular embodiments of the present invention, at least one dipodal aminosilane has the formula (I):

[0017]

[0018] In the above formula (I), X represents -NR 1 -, -NR 1 CH2-NR 1 -, NR 1 -СН2-CH2-NR 1 -, NR 1 -СО-NR 1 - or

[0019]

[0020] In the above formula (I), each R 1 independently denotes H, CH3, or C2H5. Each R 2 independently denotes a linear or branched alkylene group having from 1 to 6 carbon atoms. Each R 3 independently represents a linear or branched alkyl group having from 1 to 4 carbon atoms. Each R 4 independently represents H or a linear or branched alkyl group having from 1 to 4 carbon atoms, f represents 0, 1 or 2.

[0021] The reason why dipodal aminosilanes are particularly advantageous for forming stable oil-water interfaces compared to conventional silanes is not fully understood. Without being bound by any theory, it can be speculated that this advantage is due to the specific, bidirectional arrangement of the silane moieties within the molecule.

[0022] Typical examples of dipodal aminosilanes include bis(3-(triethoxysilyl)propyl)amine, N,N'-bis(3-(trimethoxysilyl)propyl)urea, bis(3-(methyldiethoxysilyl)propyl)amine, N,N-bis(3-(trimethoxysilyl)propyl)ethane-1,2-diamine, bis(3-(methyldimethoxysilyl)propyl)-N-methylamine, and N,N-bis(3-(triethoxysilyl)propyl)piperazine.

[0023] In preferred embodiments of the present invention, the dipodal aminosilane is a secondary aminosilane. Using a secondary dipodal aminosilane instead of a primary aminosilane reduces the reactivity of the stabilizer with electrophilic species, particularly aldehydes. However, perfumes containing high levels of aldehydes can be easily encapsulated.

[0024] In particular embodiments of the present invention, the dipodal secondary aminosilane is bis(3-(triethoxysilyl)propyl)amine. This particular secondary aminosilane has the advantage of releasing ethanol instead of the more toxic and less desirable methanol during the interpolycondensation of the ethoxysilane groups.

[0025] In particular embodiments of the present invention, the polymeric stabilizer is formed by combining a polymeric surfactant with at least one dipodal aminosilane and an additional aminosilane, preferably an aromatic aminosilane, even more preferably selected from the group consisting of compounds having the formula (II):

[0026]

[0027] In the above formula (II) R 1 denotes a linear or branched alkylene group having from 1 to 6 carbon atoms. Each R 2 independently represents a linear or branched alkyl group having from 1 to 4 carbon atoms. Each R 3 independently represents H or a linear or branched alkyl group having from 1 to 4 carbon atoms, f represents 0, 1, or 2.

[0028] It was found that the inclusion of additional aminosilane in the polymer stabilizer results in a particularly stable oil-water interface.

[0029] In particular embodiments of the present invention, the aromatic aminosilane is selected from the group consisting of N-(3-(trimethoxysilyl)propyl)aniline and N-((trimethoxysilyl)methyl)aniline.

[0030] In particular embodiments of the present invention, the polymeric stabilizer is formed by combining a polymeric surfactant with at least one dipodal aminosilane and a tripodal aminosilane. The tripodal aminosilane may be an aminosilane of formula (III):

[0031]

[0032] In the above formula (III), each R 2 independently denotes a linear or branched alkylene group having from 1 to 6 carbon atoms. Each R 3independently represents a linear or branched alkyl group having from 1 to 4 carbon atoms. Each R 4 independently represents H or a linear or branched alkyl group having from 1 to 4 carbon atoms, f represents 0, 1 or 2.

[0033] In particular embodiments of the present invention, the polymeric stabilizer is formed by combining a polymeric surfactant with at least one dipodal aminosilane and a tripodal aminosilane of formula (IV):

[0034]

[0035] In the above formula (IV) R 1 denotes R 2 Si(OR 4 ) (3-f) (R 3 ) f . Each R 2 independently denotes a linear or branched alkylene group having from 1 to 6 carbon atoms. Each R 3 independently represents a linear or branched alkyl group having from 1 to 4 carbon atoms. Each R 4independently represents H or a linear or branched alkyl group having from 1 to 4 carbon atoms, f represents 0, 1 or 2.

[0036] The advantage of tripodal aminosilanes is to provide additional crosslinking capabilities within the shell.

[0037] In the context of the present invention, the polymeric surfactant is preferably soluble in the aqueous phase. Surfactants soluble in the aqueous phase promote the formation of oil-in-water emulsions.

[0038] A convenient way to evaluate the interfacial activity of a polymeric surfactant that is soluble in an aqueous phase is to measure the tension at the interface between the aqueous phase containing the polymeric surfactant and air. This tension is called "surface tension" and is usually expressed in mN / m. Surface tension can be measured by a number of methods that are well known to those skilled in the art. For example, surface tension can be measured by measuring the force required to separate a platinum ring of known circumference from the surface of the aqueous phase using a so-called du Noüy ring tensiometer (Du ). Alternatively, the surface tension can be obtained from the force required to wet a platinum or glass plate oriented perpendicular to the surface of the aqueous phase, according to the so-called Wilhelmy plate method.

[0039] For a given polymeric surfactant, the surface tension depends on the temperature and the concentration of that polymeric surfactant in the aqueous phase. Furthermore, if the polymeric surfactant is a polyelectrolyte containing cationic groups or anionic groups, or a polymer containing groups that can form cations or anions, the surface tension also depends on the ionic strength and / or pH of the aqueous phase. The surface tension of pure water is approximately 72 mN / m at 25°C.

[0040] The surface tension of the aqueous phase containing the polymeric surfactant may also depend on the age of the surface due to slow molecular movements and rearrangements on the surface.

[0041] In particular embodiments of the present invention, the polymeric surfactant is a polymer causing a surface tension of below 60 mN / m, more preferably below 55 mN / m, even more preferably below 50 mN / m, in a 1% (wt) aqueous solution containing 0.01% (wt) sodium chloride, measured after 1 hour of equilibration at at least one pH value selected from 3.5, 4.0, 4.5, 5.0, 5.5, 6.0 and 6.5 at a temperature of 25°C using a du Nouy ring tensiometer (type: K100 manufactured by Krtiss GmbH, Germany). Concentrations are given as weight percent of the total weight of the aqueous phase.

[0042] It is proposed that interfacial activity will direct the polymer to the oil / water interface where a polymer stabilizer is formed.

[0043] Preferably, the polymeric surfactant contains anionic groups or groups that can form anions, such as sulfate groups, sulfonate groups, phosphate groups, carboxylic acid groups, and anhydride groups. Without being limited by theory, it is believed that negatively charged polymers may preferentially interact with the aminosilanes mentioned above.

[0044] In particular embodiments of the present invention, the polymeric surfactant is a copolymer of maleic anhydride with ethylene and / or vinyl methyl ether. Such copolymers exhibit high interfacial activity due to the coexistence of both hydrophilic and hydrophobic moieties.

[0045] The copolymer of maleic anhydride with ethylene and / or vinyl methyl ether can be alternating. Alternating copolymers are preferable to block copolymers and random copolymers due to the more homogeneous distribution of maleic moieties along the polymer backbone.

[0046] In particular embodiments of the present invention, the copolymer of maleic anhydride with ethylene and / or vinyl methyl ether is fully or partially hydrolyzed.

[0047] Without being limited by any theory, the applicant believes that the silane groups additionally polycondensate with each other to form a silicon dioxide network at the interface, which further stabilizes that interface.

[0048] In particular embodiments of the present invention, the polymeric stabilizer is formed by combining bis(3-(triethoxysilyl)propyl)amine with (3-(trimethoxysilyl)propyl)aniline and a fully or partially hydrolyzed ethylene-maleic anhydride copolymer and / or a vinyl methyl ether-maleic anhydride copolymer, in particular in alternant form. This combination of a dipodal secondary aminosilane and an aromatic secondary aminosilane provides the desired interface stability and barrier properties. The stabilized interface becomes sufficiently impermeable to effectively encapsulate at least one perfume ingredient contained in the core. The polymeric stabilizer effectively forms a shell encapsulating at least one perfume ingredient contained in the core.

[0049] In the encapsulated compositions according to the present invention, the weight ratio of the dipodal aminosilane to the polymeric surfactant may be from 0.02 to 1, in particular from 0.2 to 0.9, even more preferably from 0.3 to 0.7. The weight ratio of the additional aminosilane to the polymeric surfactant may be from 0.02 to 1, in particular from 0.1 to 0.7, even more preferably from 0.15 to 0.5. The weight ratio of the shell to the core may be from 0.015 to 0.2, in particular from 0.03 to 0.09, even more preferably from 0.04 to 0.07.

[0050] The microcapsules mentioned above can be used alone or in combination with additional shell-forming materials to form a second shell encapsulating the first shell mentioned above, which then becomes the first shell underlying the second shell.

[0051] In particular embodiments of the present invention, the additional shell comprises at least one shell-forming material obtained by:

[0052] reaction of an alkylated polyfunctional amine or reaction of a polyfunctional amine with an aldehyde;

[0053] interaction of polyisocyanate with polyfunctional amine;

[0054] interaction of a polyfunctional amine with a polyfunctional (meth)acrylate and / or

[0055] reaction of unsaturated monomers selected from the group consisting of styrene, divinylbenzene, alkyl (meth)acrylates, polyfunctional (meth)acrylates and vinyl monomers.

[0056] The second aspect of the present invention relates to a method for producing an encapsulated composition, in particular the composition described in this application above. The method comprises the following steps:

[0057] a. dissolving a polymeric surfactant in an aqueous phase;

[0058] b. dissolving at least one dipodal aminosilane in an oil phase containing at least one perfume and / or cosmetic ingredient;

[0059] c. emulsifying an oil phase in an aqueous phase to form an oil-in-water emulsion;

[0060] d. initiating a dipodal aminosilane and a polymeric surfactant to form a first shell of a polymeric stabilizer encapsulating dispersed oil droplets, thereby forming a suspension of microcapsules.

[0061] The advantage of oil-in-water emulsions is that they provide a plurality of droplets that can be used as a template for shell formation, with the shell being built around each droplet. Furthermore, the droplet size distribution in emulsions can be controlled by adjusting emulsification conditions, such as stirring speed and stirrer geometry. The result is a plurality of microcapsules with controlled average size and size distribution, with the oil phase encapsulated and forming the core of the microcapsules.

[0062] Regarding step (d), the formation of the first shell of the polymer stabilizer is preferably initiated by adjusting the pH to a value in the range of 4.0 to 5.0. The temperature is preferably maintained at room temperature for at least 1 hour, more preferably at least 2 hours, even more preferably at least 3 hours, for example 3.5 hours, and then increased to at least 60°C, preferably at least 70°C, more preferably at least 80°C, but not more than 90°C. Under these conditions, the formation of the shell is well controlled, which means that optimal stabilization of the interface is obtained.

[0063] The appropriate stirring speed and stirrer geometry can be selected to achieve the desired average droplet size and droplet size distribution. A characteristic feature of the present invention is that the polymer stabilizer has sufficient surfactant strength and is capable of promoting the formation of dispersed oil droplets with the desired small droplet size and low polydispersity.

[0064] In the method according to the present invention, a 1 liter vessel equipped with a turbine or a cross-beam stirrer with pitched beam, such as a Mig stirrer, and having a stirrer diameter to reactor diameter ratio of 0.6 to 0.8 can be used. In such a reactor, microcapsules with an average particle size D(50) of 30 micrometers or less, more preferably 20 micrometers or less, and a polydispersity range of less than 1.5, more preferably less than 1.3, even more preferably less than 1.2, can be formed at a stirring speed of less than 1000 rpm, more preferably of the order of from about 100 to about 1000 rpm, even more preferably from about 500 to 700 rpm, for example 600 rpm. Preferably, the Mig type stirrer is used when operating at a speed of 600±50 rpm.However, one skilled in the art will readily appreciate that such mixing conditions can be varied depending on the reactor size and slurry volume, the precise geometry of the stirrer, and the stirrer-to-reactor diameter ratio. For example, for a MIG-type stirrer with a stirrer-to-reactor diameter ratio of 0.5 to 0.9 and slurry volumes ranging from 0.5 to 8 tons, the preferred mixing speed in the context of the present invention is between 150 rpm and 50 rpm.

[0065] In a specific embodiment of the present invention, the weight ratio of the dipodal aminosilane to the polymeric surfactant in the emulsion is set within the range of 0.02 to 1, more preferably 0.2 to 0.9, even more preferably 0.3 to 0.7, for example 0.35 or 0.65.

[0066] In a specific embodiment of the present invention, an additional aminosilane, preferably an aromatic aminosilane, is further dissolved in the oil phase (the above-mentioned step (b)) to form a first polymer stabilizer shell encapsulating the dispersed oil droplets (the above-mentioned step (d)). The weight ratio of the additional aminosilane to the polymeric surfactant in the emulsion can be set within the range of 0.2 to 0.7, in particular, especially 0.3 to 0.5, for example, 0.35.

[0067] In a specific embodiment of the present invention, the ratio of the shell material to the oil in the emulsion is set within the range of 0.015 to 0.2, more preferably 0.03 to 0.09, even more preferably 0.04 to 0.07, for example 0.06.

[0068] The microcapsules obtained by the above-mentioned method can be used as such or as a first shell on which a second shell can be formed, containing at least one additional shell-forming material.

[0069] Additional shell-forming materials may be added after the above polymer stabilizer shell is formed. The method may then include the following steps:

[0070] a. dissolving a polymeric surfactant in an aqueous phase;

[0071] b. dissolving at least one dipodal aminosilane in an oil phase containing at least one perfume and / or cosmetic ingredient;

[0072] c. emulsifying an oil phase in an aqueous phase to form an oil-in-water emulsion;

[0073] d. initiating a dipodal aminosilane and a polymeric surfactant to form a polymeric stabilizer shell encapsulating dispersed oil droplets, thereby forming a suspension of microcapsules;

[0074] e. providing additional shell-forming materials and causing these additional shell-forming materials to interact and form an additional shell encapsulating the microcapsules formed in step (d).

[0075] After microcapsule formation, the encapsulated composition is typically cooled to room temperature. Before, during, or after cooling, the encapsulated composition may undergo further processing. Further processing may include treating the composition with antimicrobial preservatives, which are well known in the art. Further processing may also include the addition of a suspending agent, such as a hydrocolloid suspending agent, to promote stable physical dispersion of the microcapsules and prevent any segregation or coalescence. Any additional adjuvants may also be added at this time.

[0076] The case where a polyfunctional amine and a polyisocyanate are used as additional shell-forming monomers represents a specific method for forming the encapsulated composition of the present invention. The method may include the following steps:

[0077] a. forming a suspension of microcapsules having a first shell comprising a polymeric stabilizer according to the present invention, as described in this application above;

[0078] b. adding at least one polyisocyanate, in particular adding a polyisocyanate (A) and a polyisocyanate (B) that is different from the polyisocyanate (A);

[0079] c. adding at least one polyfunctional amine;

[0080] d. forming a second shell around the first shell formed in step (a).

[0081] In the above-described method, the pH of the aqueous phase of the suspension formed in step (a) can be adjusted to a value in the range of 4 to 8, preferably 5 to 7, for example, about 6. The pH can be adjusted using an inorganic base, such as sodium hydroxide solution or carbonate buffer salts.

[0082] Organic isocyanates are compounds in which the isocyanate group is bonded to an organic residue (RN=C=O or R-NCO). In the context of the present invention, polyisocyanates (or polyfunctional isocyanates) are organic isocyanates with two or more (e.g., 3, 4, 5, etc.) isocyanate groups in the molecule. Suitable polyisocyanates are, in particular, aromatic, alicyclic, or aliphatic.

[0083] The polyisocyanate A mentioned above is preferably an anionically modified polyisocyanate that contains at least two isocyanate groups and at least one anionic or anionogenic functional group. An "anionogenic functional group" is a group that can become anionic depending on the chemical environment, in particular pH. Suitable anionic or anionogenic groups are, in particular, carboxylic acid groups, sulfonic acid groups, phosphonic acid groups, and their salts. Suitable salts can be sodium, potassium, or ammonium salts. Ammonium salts are preferred.

[0084] The anion-modified polyisocyanate A may be selected in each case from anion-modified hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, hexamethylene diisocyanate isocyanurate, and mixtures thereof.

[0085] In a particularly preferred embodiment, the anionically modified polyisocyanate A is a modified isocyanurate of hexamethylene diisocyanate sold by Covestro under the trade name Bayhydur® XP2547.

[0086] In one aspect of the present invention, the polyisocyanate B may be a non-ionic polyisocyanate.

[0087] Preferably, the non-ionic polyisocyanate B is selected from the group consisting of hexamethylene diisocyanate, tetramethylene diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 2,4- and 2,6-toluene diisocyanate and mixtures of their isomers, 2,4'- and 4,4'-diphenylmethane diisocyanate and mixtures of their isomers, xylylene diisocyanate (e.g. Desmodur® quix 175 sold by Covestro), optionally in the form of a trimethylolpropane (TMP) adduct (e.g. commercially available under the trade name Takenate™ D-110N), biurets, allophanates and / or isocyanurates of the above polyisocyanates or mixtures thereof.

[0088] A preferred commercially available non-ionic polyisocyanate B is dicyclohexylmethane diisocyanate, particularly sold by Covestro AG under the trade name Desmodur® W1.

[0089] A preferred commercially available non-ionic polyisocyanate B is hexamethylene diisocyanate, particularly that sold by Covestro AG under the trade name Desmodur® N3200.

[0090] A preferred commercially available non-ionic polyisocyanate B is isophorone diisocyanate, particularly sold by Covestro AG under the trade name Desmodur® Z.

[0091] The advantage of these polyisocyanates is that they are non-aromatic and therefore more stable and less prone to oxidation, yet have reactivity with polyamines and a suitable molecular structure to form impermeable encapsulating resins.

[0092] The weight ratio of the anionically modified polyisocyanate A to the nonionic polyisocyanate B may be in the range of 10:1 to 1:10, more preferably in the range of 1:1 to 1:5, and in particular in the range of 1:2 to 1:4. Such weight ratios provide resins having the highest impermeability and are therefore most suitable for encapsulation.

[0093] In the context of the present invention, "polyfunctional amine" means amines that contain at least two groups capable of reacting with NCO groups, where at least one of these groups capable of reacting with NCO groups is a primary or secondary amino group.

[0094] The polyfunctional amine is preferably selected from diamines, triamines, tetramines and higher order polyfunctional amines, amino alcohols, melamines, ureas, hydrazines, polymeric polyamines and mixtures thereof.

[0095] Preferred are polymeric polyamines having a weight-average molecular weight of at least 300 g / mol. More preferred are polymeric polyamines having a weight-average molecular weight of 500 to 2,000,000 g / mol, in particular 700 to 1,000,000 g / mol, and even more preferably 800 to 500,000 g / mol.

[0096] Preferred commercially available polyethyleneimines are sold by BASF SE under the trade name Lupasol®, in particular Lupasol™ G100.

[0097] It is preferable to use polyethyleneimine and isocyanate compounds in a weight ratio of 1:1 to 1:5, in particular 1:2 to 1:3, or in a ratio of 1:1 to 1:10 on a dry basis, in particular 1:4 to 1:6. Such weight ratios provide resins having the highest encapsulation efficiency and are therefore most suitable for encapsulation.

[0098] The formation of shells around the droplets in step (d) can be carried out by heating. This can be achieved at a temperature of at least 50°C, preferably at least 60°C, more preferably in the range of 65°C to 90°C, to ensure sufficiently rapid reaction progression. It may be preferable to increase the temperature continuously or in stages (for example, by 5°C in each case) until the reaction is substantially complete. The dispersion can then be cooled to room temperature.

[0099] The reaction time generally depends on the nature of the reactive materials forming the walls, the amount of said materials used, and the temperature used. The reaction time ranges from a few minutes to several hours. Typically, microcapsule formation takes from approximately 60 minutes to 6 hours, or up to 8 hours, at the temperatures specified above.

[0100] According to another specific embodiment of the present invention, the additional shell-forming monomers may be selected from precondensates of polyfunctional amines, more preferably precondensates of melamine and urea with aldehydes, and in particular formaldehyde.

[0101] The method for producing the corresponding encapsulated composition may include the following steps:

[0102] a. forming a suspension of microcapsules having a first shell comprising a polymeric stabilizer according to the present invention, as described in this application above;

[0103] b. adding at least one polyfunctional amine precondensate;

[0104] c. forming a second shell around the first shell formed in step (a).

[0105] The pH range of the reaction in step (c) is in the acidic region, more preferably from 3 to 6, for example 4.4±0.5, and the reaction temperature is from about 50°C to 95°C, more preferably from 70°C to 90°C. In addition, a formaldehyde scavenger can be used to reduce the level of formaldehyde in the final suspension, and the formaldehyde scavenger can be added before, during or after cooling the suspension to room temperature. 0106 According to the method of the present invention, a functional coating can be applied to the first or second shell of the core-shell microcapsules, if desired. The functional coating can completely or partially cover the microcapsule shell. Regardless of whether the functional coating is charged or uncharged, its primary purpose is to modify the surface properties of the microcapsule to achieve a desired effect, such as improving microcapsule deposition on a treated surface such as tissue, skin, or human hair. Functional coatings can be applied subsequently to already formed microcapsules, or they can be physically incorporated into the microcapsule shell during shell formation.They can be attached to the shell through physical forces, physical interactions such as hydrogen bonding, ionic interactions, hydrophobic interactions, electron transfer interactions, or they can be covalently bonded to the shell.

[0107] If the functional coating is to be attached to the shell via physical association, the coating's chemical structure will be determined to some extent by its compatibility with the shell chemistry, as some association with the microcapsule shell is required. If the functional coating is to be covalently bonded to the shell, this can be facilitated by incorporating materials into the shell that carry functional groups that are capable of reacting with the coating material.

[0108] Suitable coating materials may be based on polysaccharides, polypeptides, polycarbonates, polyesters, polyolefins (vinyl, acrylic, acrylamide, polydiene), polyesters, polyethers, polyurethanes, polyoxazoline, polyamine, silicone, polyphosphazine, polyaromatic, and polyheterocyclic. A more detailed list of coating materials can be found in patent literature, for example, EP 1 797 947 A2, which discloses coating materials that can be used as precipitation additives.

[0109] Particularly preferred coating materials may be selected from the group consisting of polymethyl (meth) acrylate, polydimethylaminoethyl (meth) acrylate, polybutyl (meth) acrylate, polydiallyl dimethyl ammonium chloride, and mixtures thereof.

[0110] If the coating material is a polymer, it can be formed in situ during the coating process by polymerizing the monomers of the coating material. More preferably, suitable monomers can be added to the suspension of core-shell microcapsules formed according to the method described in this application and initiated for polymerization, as well as react with functional groups on the shell, if applicable, to form a polymeric coating material that is covalently bonded to the shell and that at least partially coats it.

[0111] Accordingly, in a particular embodiment of the present invention, there is provided a method for forming a microcapsule and an encapsulated composition containing the same, wherein said method comprises the following steps:

[0112] a. forming a suspension of microcapsules according to any method described in this application above;

[0113] b. adding a polymerizable monomer to the suspension and initiating the monomer to both polymerize and react with functional groups available on the microcapsule shells to form a coating material covalently bonded to the core-shell microcapsule shells.

[0114] The coating polymer may be a cationic or cationic ampholytic polymer. In the context of the present invention, an "ampholytic polymer" is understood to mean a polymer containing both cationic and anionic groups, or containing corresponding ionizable groups. A cationic ampholytic polymer contains more cationic groups than anionic groups or groups that can form anions, and as such, has an overall positive charge.

[0115] The ampholytic polymer may contain from 1 to 99 mol % of cationic groups and from 1 to 99 mol % of anionic groups or groups that can form an anion. In a preferred embodiment of the present invention, the ampholytic polymer contains from 2 to 99 mol %, in particular from 30 to 95 mol %, and more preferably from 60 to 90 mol %, of cationic groups and from 1 to 98 mol %, in particular from 5 to 70 mol %, and more preferably from 10 to 40 mol % of anionic groups or groups that can form an anion.

[0116] The cationic groups in the cationic polymer can be pH independent. The cationic groups in the cationic polymer can be quaternary ammonium groups.

[0117] The cationic polymer can be obtained from at least one monomer bearing a quaternary ammonium functional group. In particular, the cationic monomer can be selected from the group consisting of quaternized dimethylaminoethyl acrylate (ADAME), quaternized dimethylaminoethyl methacrylate (MADAME), dimethyldiallylammonium chloride (DADMAC), acrylamidopropyltrimethylammonium chloride (ARTAC), and methacrylamidopropyltrimethylammonium chloride (MAPTAC).

[0118] When the cationic polymer contains anionic groups or groups that can form anions, it can also be obtained from a monomer selected from the group consisting of acrylic-based monomers, including acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, and strongly acidic monomers, for example, monomers with a functional group of the sulfonic or phosphonic acid type, such as 2-acrylamido-2-methylpropanesulfonic acid, vinylsulfonic acid, vinylphosphonic acid, allylsulfonic acid, allylphosphonic acid, styrene sulfonic acid. The acrylic-based monomer can also be any water-soluble salts of these monomers, wherein the salt is an alkali metal, alkaline earth metal, or ammonium salt. The most preferred acrylic-based monomer is acrylic acid, methacrylic acid, or a water-soluble salt thereof.

[0119] The cationic polymer can also be obtained from a non-ionic monomer selected from the group consisting of water-soluble vinyl monomers, more preferably acrylamide, methacrylamide, N-isopropylacrylamide, N,N-dimethylacrylamide, N-methylolacrylamide, N-vinylformamide, N-vinylacetamide, N-vinylpyridine and / or N-vinylpyrrolidone.

[0120] The cationic polymer may be an ampholytic copolymer obtained from a cationic monomer or a monomer that can form cations, in particular containing at least one quaternary ammonium group, an anionic monomer or a monomer that can form anions, in particular based on acrylic acid, methacrylic acid or a derivative thereof, and optionally a nonionic monomer. Such polymers provide an optimal combination of shell compatibility, good dispersion efficiency, good flow properties, and excellent affinity for the various substrates mentioned above.

[0121] In a more specific embodiment, the ampholytic copolymer is a copolymer of acrylic acid and dimethyl diallylammonium chloride (DADMAC).

[0122] The ampholytic polymer can be used in the encapsulated composition according to the present invention in an amount of from 1 to 20% (mass), more preferably from 2 to 10% (mass), based on the weight of the composition.

[0123] The ampholytic polymer can be prepared using polymerization methods well known to those skilled in the art. These known polymerization methods include solution polymerization, gel polymerization, precipitation polymerization, inverse emulsion polymerization, aqueous emulsion polymerization, suspension polymerization, and micellar polymerization.

[0124] In particular embodiments of the present invention, at least one perfume ingredient is selected from the group consisting of the following substances: ADOXAL™ (2,6,10-trimethylundec-9-enal); AGRUMEX™ (2-(tert-butyl)cyclohexylacetate); ALDEHYDE C 10 DECYL (decanal); ALDEHYDE C 11 MOA (2-methyldecanal); ALDEHYDE C 11 UNDECYLENYL (undec-10-enal); ALDEHYDE C 110 UNDECYLENYL (undecanal); ALDEHYDE C 12 LAURIC (dodecanal); ALDEHYDE C 12 MNA PURE (2-methylundecanal); ALDEHYDE ISO C 11 ((E)-undec-9-enal); ALDEHYDE TANGARIN 10% / TECH ((E)-dodec-2-enal); ALLYLAMIL GLYCOLATE (allyl-2-(isopentyloxy)acetate); ALLYL CYCLOHEXYL PROPIONATE (allyl-3-cyclohexylpropanate); ALLYL OENANTATE (allyl heptanoate); AMBER CORE™ (1-((2-(tert-butyl)cyclohexyl)oxy)butan-2-ol); AMBERMAX™ (1,3,4,5,6,7-hexahydro-beta,1,1,5,5-pentamethyl-2H-2,4a-methanonaphthalene-8-ethanol); AMYLSALICYLATE (pentyl-2-hydroxybenzoate); AFERMATE (1-(3,3-dimethylcyclohexyl)ethyl formate);BELAMBRE™ ((1R,2S,4R)-2'-isopropyl-1,7,7-trimethylspiro[bicyclo[2.2.1]heptane-2,4'-[1,3]dioxane]); BIGARYL (8-(sec-butyl)-5,6,7,8-tetrahydroquinoline); BIOSAMBRENE FORTE™ (BIOSAMBRENE FORTE) ((ethoxymethoxy)cyclododecane); BOISIRIS™ ((1S,2R,5R)-2-ethoxy-2,6,6-trimethyl-9-methylenebicyclo[3.3.1]nonane); BORNYL ACETATE ((2S,4S)-1,7,7-trimethylbicyclo[2.2.1]heptan-2-yl acetate); BUTYL BUTYROLACTATE (1-butoxy-1-oxopropan-2-yl butyrate); BUTYL CYCLOHEXYL ACETATE PARA (4-(tert-butyl)cyclohexyl acetate); CARYOPHYLLENE (Z)-4,11,11-trimethyl-8-methylenebicyclo[7.2.0]undec-4-ene); CASHMERAN™ (1,1,2,3,3-pentamethyl-2,3,6,7-tetrahydro-1H-inden-4(5H)-one); CASSYRANE™ (5-tert-butyl-2-methyl-5-propyl-2H-furan); CITRAL ((E)-3,7-dimethylocta-2,6-dienal); CITRAL LEMAROME™ N ((E)-3,7-dimethylocta-2,6-dienal); CITRATHAL™ R ((7)-1,1-diethoxy-3,7-dimethylocta-2,6-diene); CITRONELLAL (3,7-dimethyloct-6-enal); CITRONELLOL (3,7-dimethyloct-6-en-1-ol);CITRONELLYL ACETATE (3,7-dimethyloct-6-en-1-yl acetate); CITRONELLYL FORMATE (3,7-dimethyloct-6-en-1-yl formate); CITRONELLYLNITRIL (3,7-dimethyloct-6-ennitrile); CITRONELLYL PROPIONATE (3,7-dimethyloct-6-en-1-ylpropionate); CLONAL (dodecanenitrile); CORANOL (4-cyclohexyl-2-methylbutan-2-ol); COSMONE™ ((Z)-3-methylcyclotetradec-5-enone); CYCLAMENALDEHYDE (3-(4-isopropylphenyl)-2-methylpropanal); CYCLOGALBANATE (allyl-2-(cyclohexyloxy)acetate); CYCLOHEXYLSALICYLATE (cyclohexyl-2-hydroxybenzoate); CYCLOMIRAL (8,8-dimethyl-1,2,3,4,5,6,7,8-octahydronaphthalene-2-carbaldehyde); DAMASKENONE ((E)-1-(2,6,6-trimethylcyclohexa-1,3-dien-1-yl)but-2-en-1-one); DAMASCON ALPHA ((E)-1-(2,6,6-trimethylcyclohex-2-en-1-yl)but-2-en-1-one); DAMASCON DELTA ((E)-1-(2,6,6-trimethylcyclohex-3-en-1-yl)but-2-en-1-one); DECENAL-4-TPAHC ((E)-dec-4-enal); DELPHON (2-pentylcyclopentanone); DIHYDROANETHOLE (1-(1-(3,3-dimethylcyclohexyl)ethyl)-3-ethyl ester of propanedioic acid);DIHYDROJASMONE (3-methyl-2-pentylcyclopent-2-enone); DIMETHYLBENZYLCARBINOL (2-methyl-1-phenylpropan-2-ol); DIMETHYLBENZYLCARBINYL ACETATE (2-methyl-1-phenylpropan-2-yl acetate); DIMETHYLBENZYLCARBINYLBUTYRATE (2-methyl-1-phenylpropan-2-ylbutyrate); DIMETHYLOCTENONE (4,7-dimethyloct-6-en-3-one); DIMETHOL (2,6-dimethylheptan-2-ol); DIPENTENE (1-methyl-4-(prop-1-en-2-yl)cyclohex-1-ene); DUPICAL™ ((E)-4-((3a8,7aS)-hexahydro-1H-4,7-methanoinden-5(6H)-ylidene)butanal); EBANOL™ ((E)-3-methyl-5-(2,2,3-trimethylcyclopent-3-en-1-yl)pent-4-en-2-ol); ETHYL CAPRATE (ethyl hexanate); ETHYL CAPRYLATE (ethyl octanate); ETHYLLINALOOL ((E)-3,7-dimethylnona-1,6-dien-3-ol); ETHYLLINALYL ACETATE ((2)-3,7-dimethylnona-1,6-dien-3-yl acetate); ETHYLOENANTATE (ethyl heptanate); ETHYLSAFRANATE (ethyl 2,6,6-trimethylcyclohexa-1,3-diene-1-carboxylate); EUCALYPTOL ((1s,4s)-1,3,3-trimethyl-2-oxabicyclo[2.2.2]octane); PHENCHYL ACETATE ((2S)-1,3,3-trimethylbicyclo[2.2.1]heptan-2-yl acetate);FENHYL ALCOHOL ((1S,2R,4R)-1,3,3-trimethylbicyclo[2.2.1]heptan-2-ol); FIXOLIDE™ (1-(3,5,5,6,8,8-hexamethyl-5,6,7,8-tetrahydronaphthalen-2-yl)ethanone); FLORALOZONE™ (3-(4-ethylphenyl)-2,2-dimethylpropanal); FLORGYDRAL (3-(3-isopropylphenyl)butanal); FLOROCYCLENE™ ((3aR,6S,7aS)-3a,4,5,6,7,7a-hexahydro-1H-4,7-methanoinden-6-ylpropionate); FLOROPAL™ (2,4,6-trimethyl-4-phenyl-1,3-dioxane); FRESKOMENTHE™ (2-(sec-butyl)cyclohexanone); FRUITATE ((3aS,4S,7R,7aS)-ethyl octahydro-1H-4,7-methanoindene-3a-carboxylate); FRUTONIL (2-methyldecanenitrile); GALBANONE™ PURE (1-(3,3-dimethylcyclohex-1-en-1-yl)pent-4-en-1-one); GARDOCYCLENE™ (GARDOCYCLENE) ((3aR,6S,7aS)-3a,4,5,6,7,7a-hexahydro-1H-4,7-methanoinden-6-yl isobutyrate); GERANIOL ((E)-3,7-dimethylocta-2,6-dien-1-ol); GERANYL ACETATE SYNTHETIC ((E)-3,7-dimethylocta-2,6-dien-1-yl acetate); GERANYL ISOBUTYRATE ((E)-3,7-dimethylocta-2,6-dien-1-yl isobutyrate);GIVESCONE™ (ethyl-2-ethyl-6,6-dimethylcyclohex-2-enecarboxylate); HABANOLIDE™ ((E)-oxacyclohexadec-12-en-2-one); HEDIONE™ (methyl-3-oxo-2-pentylcyclopentaneacetate); HERBANATE™ ((2S)-ethyl-3-isopropylbicyclo[2.2.1]hept-5-ene-2-carboxylate); HEXENYL-3-CIS BUTYRATE ((Z)-hex-3-en-1-ylbutyrate); HEXYLCORIC ALDEHYDE ((E)-2-benzylideneoctanal); HEXYLISOBUTYRATE (hexylisobutyrate); HEXYL SALICYLATE (hexyl-2-hydroxybenzoate); INDOFLOR™ (4,4a,5,9b-tetrahydroindeno[1,2d][1,3]dioxin); IONONE BETA ((E)-4-(2,6,6-trimethylcyclohex-1-en-1-yl)but-3-en-2-one); IRIZONE ALPHA ((E)-4-(2,6,6-trimethylcyclohex-2-en-1-yl)but-3-en-2-one); IRON ALPHA ((E)-4-(2,5,6,6-tetramethylcyclohex-2-en-1-yl)but-3-en-2-one); ISO E SUPER™ (1-(2,3,8,8-tetramethyl-1,2,3,4,5,6,7,8-octahydronaphthalen-2-yl)ethanone); ISOCYCLOCITRAL (2,4,6-trimethylcyclohex-3-enecarbaldehyde); ISONONYLACETATE (3,5,5-trimethylhexyl acetate); ISOPROPYLMETHYL-2-BUTYRATE (isopropyl-2-methylbutanoate);ISORALDEINE™ 70 ((E)-3-methyl-4-(2,6,6-trimethylcyclohex-2-en-1-yl)but-3-en-2-one); JASMACYCLENE™ ((3aR,6S,7aS)-3a,4,5,6,7,7a-hexahydro-1H-4,7-methanoinden-6-yl acetate); JASMON CIS ((Z)-3-methyl-2-(pent-2-en-1-yl)cyclopent-2-enone); KARANAL™ (5-(sec-butyl)-2-(2,4-dimethylcyclohex-3-en-1-yl)-5-methyl-1,3-dioxane); COAVONE ((Z)-3,4,5,6,6-pentamethylhept-3-en-2-one); LEAF ACETAL ((Z)-1-(1-ethoxyethoxy)hex-3-ene); LEMONILE™ (LEMONIL) ((2E,6Z)-3,7-dimethylnona-2,6-dienenitrile); LIFFAROME™ GIV ((Z)-hex-3-en-1-ylmethylcarbonate); LILIAL™ (3-(4-(tert-butyl)phenyl)-2-methylpropanal); LINALOOL (3,7-dimethylocta-1,6-dien-3-ol); LINALYL ACETATE (3,7-dimethylocta-1,6-dien-3-yl acetate); MAHONIAL™ (MAHONIAL) ((4E)-9-hydroxy-5,9-dimethyl-4-decenal); MALTYL ISOBUTYRATE (2-methyl-4-oxo-4H-pyran-3-yl isobutyrate); MANZANATE (ethyl 2-methylpentanate); MELONAL™ (MELONIAL) (2,6-dimethylhept-5-enal); MENTHOL (2-isopropyl-5-methylcyclohexanol);MENTHONE (2-isopropyl-5-methylcyclohexanone); METHYLCEDRYLKETONE (1-((1S,8aS)-1,4,4,6-tetramethyl-2,3,3a,4,5,8-hexahydro-1H-5,8a-methanoazulen-7-yl)ethanone); METHYLNONYLKETONE EXTRA (undecan-2-one); METHYLOCTINE CARBONATE (methylnon-2-inoate); METHYL PAMPLEMUS (6,6-dimethoxy-2,5,5-trimethylhex-2-ene); MIRALDENE (4-(4-methylpent-3-en-1-yl)ciutohex-3-enecarbaldehyde); NECTARYL (2-(2-(4-methylcyclohex-3-en-1-yl)propyl)cyclopentanone); NEOBERGAMATE™ FORTE (2-methyl-6-methyleneoct-7-en-2-yl acetate); NEOFOLIONE™ ((E)-methylnon-2-enoate); NEROLIDYLE™ ((Z)-3,7,11-trimethyldodeca-1,6,10-trien-3-yl acetate); NERILACETATE HC ((Z)-3,7-dimethylocta-2,6-dien-1-yl acetate); NONADIL (6,8-dimethylnonan-2-ol); NONENAL-6-CIS ((Z)-non-6-enal); NYMPHEAL™ (3-(4-isobutyl-2-methylphenyl)propanal); ORIVONE™ (4-(tert-pentyl)cyclohexanone); PARADISAMIDE™ (2-ethyl-N-methyl-N-(m-tolyl)butanamide); PELARGEN (2-methyl-4-methylene-6-phenyltetrahydro-2H-pyran);PEONILE™ (2-cyclohexylidene-2-phenylacetonitrile); PETALIA™ (2-cytohexylidene-2-(o-tolyl)acetonitrile); PIVAROSE™ (2,2-dimethyl-2-phenylethylpropanate); PRECYCLEMONE™ B (1-methyl-4-(4-methylpent-3-en-1-yl)cyclohex-3-enecarbaldehyde); PYRALONE™ (6-(sec-butyl)quinoline); RADJANOL™ SUPER ((E)-2-ethyl-4-(2,2,3-trimethylcyclopent-3-en-1-yl)but-2-en-1-ol); RASPBERRY KETONE (N112) (4-(4-hydroxyphenyl)butan-2-one); RHUBAFURANE™ (2,2,5-trimethyl-5-pentylcyclopentanone); ROSACETOL (2,2,2-trichloro-1-phenylethyl acetate); ROSALVA (dec-9-en-1-ol); ROSIFOLIUM ((1-methyl-2-(5-methylhex-4-en-2-yl)cyclopropyl)-methanol); ROSYRANE™ SUPER (4-methylene-2-phenyltetrahydro-2H-pyran); SERENOLIDE (2-(1-(3,3-dimethylcyclohexyl)ethoxy)-2-methylpropylcyclopropanecarboxylate); SILVIAL™ (3-(4-isobutylphenyl)-2-methylpropanal); SPIROGALBANONE™ (1-(spiro[4.5]dec-6-en-7-yl)pent-4-en-1-one);STEMONE™ (STEMONE) ((E)-5-methylheptan-3-one oxime); SUPER MUGUET™ ((E)-6-ethyl-3-methyloct-6-en-1-ol); SYLKOLIDE™ ((E)-2-((3,5-dimethylhex-3-en-2-yl)oxy)-2-methylpropylcyclopropanecarboxylate); TERPINENE GAMMA (1-methyl-4-propan-2-ylcyclohexa-1,4-diene); TERPINOLENE (1-methyl-4-(propan-2-ylidene)cyclohex-1-ene); TERPINYL ACETATE (2-(4-methylcyclohex-3-en-1-yl)propan-2-yl acetate); TETRAHYDROLINALOOLL (3,7-dimethyloctan-3-ol); TETRAHYDROMYRCENOL (2,6-dimethyloctan-2-ol); TIBETOLIDE (oxacyclohexadecan-2-one); TRIDECENE-2-NITRILE ((E)-tridec-2-enenitrile); UNDECAVERTOL ((E)-4-methyldec-3-en-5-ol); VELOUTONE™ (2,2,5-trimethyl-5-pentylcyclopentanone); VIRIDINE™ ((2,2-dimethoxyethyl)benzene); ZINARINE™ (2-(2,4-dimethylcyclohexyl)pyridine) and mixtures thereof.

[0125] A complete list of perfume ingredients that can be encapsulated according to the present invention can be found in perfumery literature, such as "Perfume & Flavor Chemicals", S. Arctander, Allured Publishing, 1994.

[0126] In particular embodiments of the present invention, the core may also contain cosmetic ingredients.

[0127] Preferably, the cosmetic ingredients have a calculated octanol / water partition coefficient (Clog P) of 1.5 or more, more preferably 3 or more. Alternatively, the Clog P of the cosmetic ingredient is preferably from 2 to 7.

[0128] Particularly suitable cosmetic ingredients can be selected from the group consisting of emollients, smoothing active ingredients, moisturizing active ingredients, soothing and relaxing active ingredients, beautifying active ingredients, anti-aging active ingredients, drainage active ingredients, remodeling active ingredients, skin-smoothing active ingredients, preservatives, antioxidant active ingredients, antibacterial or bacteriostatic active ingredients, cleansing active ingredients, lubricating active ingredients, structuring agents, hair conditioning agents, bleaching agents, texturizing agents, softening active ingredients, anti-dandruff active ingredients, and exfoliating agents.

[0129] Particularly suitable cosmetic ingredients include, but are not limited to, hydrophobic polymers such as alkyl dimethyl siloxanes, polymethyl silsesquioxanes, polyethylene, polyisobutylene, styrene-ethylene-styrene and styrene-butylene-styrene block copolymers, mineral oils such as hydrogenated isoparaffins, silicone oils, vegetable oils such as argan oil, jojoba oil, aloe vera oil, fatty acids and fatty alcohols and their esters, glycolipids, phospholipids, sphingolipids such as ceramides, sterols and steroids, terpenes, sesquiterpenes, triterpenes and their derivatives, essential oils such as arnica oil, artemisia oil, cinchona oil, birch leaf oil, calendula oil, cinnamon oil, oil Echinacea, eucalyptus oil, ginseng oil, jujube oil, sunflower oil, jasmine oil, lavender oil, lotus seed oil, perilla oil, rosemary oil, sandalwood oil, tea tree oil, thyme oil, valerian oil, wormwood oil,ylang-ylang oil, yucca oil.,

[0130] The resulting encapsulated composition, presented in the form of a suspension of microcapsules suspended in an aqueous suspending medium, can be incorporated as such into a consumer product base. However, if desired, the suspension can be dried to obtain the encapsulated composition in the form of a dry powder. Drying of the microcapsule suspension is conventional and can be carried out according to methods known in the art, such as spray drying, evaporation, lyophilization, or the use of a desiccant. Typically, as is common in the art, the dried microcapsules will be dispersed or suspended in a suitable powder, such as powdered silicon dioxide, which can act as a filler or flow enhancer. Such a suitable powder can be added to the encapsulated composition before, during, or after the drying step.

[0131] In a third aspect, the present invention provides an encapsulated composition obtainable by any of the methods described in this application above.

[0132] In a fourth aspect, the present invention provides the use of the encapsulated composition described in this application above for improving the properties of a perfume and / or cosmetic ingredient in a consumer product.

[0133] The fifth aspect of the present invention relates to a consumer product, in particular to a consumer product suitable for use in rinse-off products, containing the encapsulated composition described in this application above. The consumer product is preferably selected from the group consisting of detergents and fabric conditioners, hair conditioners, shampoos, liquid detergents for hard surfaces, cleaning agents for hard surfaces, washing powders, soaps, shower gels and skin care products.

[0134] The encapsulated compositions of the present invention are particularly suitable for use as carriers for delivering perfumes in consumer products that require microcapsules to adhere well to the substrate to ensure optimal perfume benefits. Such consumer products include shampoos and hair conditioners, as well as fabric treatment products such as laundry detergents and fabric softeners.

[0135] The sixth aspect of the present invention relates to a polymeric stabilizer formed by combining a polymeric surfactant with a dipodal aminosilane and, optionally, an additional aminosilane, in particular for use as a first shell in the formation of a core-shell microcapsule. This first shell stabilizes the microcapsule core / water interface and is sufficiently impermeable to perfume ingredients to be used as the sole encapsulating shell. It can also be encapsulated or partially encapsulated by a second shell, which can provide additional stability and / or additional functional groups. Furthermore, the first and second shells can also be coated to provide additional stability and / or additional functional groups.

[0136] The seventh aspect of the present invention relates to the use of the polymeric stabilizer described in this application in the encapsulation of perfume and / or cosmetic ingredients. The polymeric stabilizer stabilizes oil / water interfaces and thus provides a template for the preparation of encapsulated compositions of perfume and / or cosmetic substances.

[0137] The present invention also relates to a method for improving the properties of a perfume and / or cosmetic ingredient in a consumer product by adding an encapsulated composition according to the present invention.

[0138] Furthermore, the present invention relates to a method for encapsulating a perfume and / or cosmetic ingredient, in which the polymeric stabilizer described in this application stabilizes and encapsulates oil droplets of an oil-in-water emulsion, and in which the oil phase contains at least one perfume and / or cosmetic ingredient.

[0139] The following are a number of examples which serve to further illustrate the present invention.

[0140] Example 1

[0141] Formation of microcapsules having a first shell containing a polymer stabilizer according to the present invention

[0142] In Examples 1.1-1.6, a series of core-shell microcapsules were prepared in which the levels of polymeric surfactant (ZeMac E400, ex Vertellus), dipodal aminosilane (bis(3-(triethoxysilyl)propyl)amine) and additional aminosilane (((trimethoxysilyl)propyl)aniline) were varied according to Table 1.

[0143] Microcapsules were obtained by carrying out the following steps:

[0144] a. preparing a core composition containing a well-defined amount (see Table 1) of a dipodal aminosilane (bis(3-(triethoxysilyl)propyl)amine) and a well-defined amount (see Table 1) of an additional aminosilane (((trimethoxysilyl)propyl)aniline) by mixing both aminosilanes with 40 g of a perfume composition;

[0145] b. emulsifying the core composition obtained in step (a) in a mixture of a well-defined amount (see Table 1) of ZeMac E400 in 39 g of water using a 300 ml reactor and a stirrer with angled cross blades operating at a stirring speed of 600 rpm at a temperature of 25±2°C;

[0146] c. adjusting the pH of the continuous phase of the emulsion to 4.4±0.5 using a 20% solution of NH3 in water and maintaining the system at a temperature of 25±2°C for 3.5 h while maintaining stirring as in step (b);

[0147] d. increasing the temperature to 80°C for 1 h while maintaining stirring as in steps (b) and (c) to complete the formation of core-shell capsules;

[0148] e. allowing the core-shell capsule suspension obtained in step (d) to cool to room temperature.

[0149] The solid content of each suspension was measured using a thermal balance operating at 120°C. The solid content, expressed as a mass percentage relative to the initial suspension applied to the balance, was taken at the point at which the rate of mass change due to drying fell below 0.1% / min. The ratio of the measured solid content to the theoretical solid content, calculated based on the mass of the perfume substances and encapsulating materials used, was taken as a measure of the encapsulation yield, expressed as % (mass).

[0150]

[0151] As can be seen from the encapsulation yield, the presence of dipodal aminosilane is a prerequisite for obtaining core-shell microcapsules with a high encapsulation yield. When using only dipodal aminosilane with ZeMac E400, the optimal range of the weight ratio of dipodal aminosilane to ZeMac E400 is 0.3 to 0.7. When using dipodal aminosilane in combination with an additional aminosilane and ZeMac E400, the optimal range of the weight ratio of dipodal aminosilane to ZeMac E400 is 0.3 to 0.5, and the weight ratio of the additional aminosilane to the polymeric surfactant in the emulsion is set within the range of 0.3 to 0.5.

[0152] Example 2

[0153] In Example 2, the microcapsules according to the prior art were obtained using the method described in US 2014 / 0331414 A1:

[0154] 462 g of water, 15 g of formic acid, and 250 g of 10% polyvinylpyrrolidone solution were added into a 1 L reactor with stirring. The stirring speed was set to 600 rpm, and 200 g of perfume was added, followed by 44.6 g of methyltriethoxysilane, 16.4 g of tetraethoxysilane, 11.4 g of dimethyldiethoxysilane, and 2.5 g of aminopropyltriethoxysilane at room temperature. After 2 h, the pH was slowly increased to 6 with 20% sodium hydroxide solution and the temperature was raised to 80 °C. After 4 h at 80 °C, the microcapsule suspension was slowly cooled to 25 °C. A microcapsule suspension with a solid content of 26% was obtained. The microcapsules had an average particle size of 17 micrometers.

[0155] Example 3

[0156] In Example 3, microcapsules having a first shell containing a polymer stabilizer according to the present invention and a second shell containing an aminoplast resin were obtained by carrying out the following steps:

[0157] a. preparing microcapsules containing the polymeric stabilizer described in Example 1.6;

[0158] b. adding 0.75g urea and 1.15g Luracoll SD (methylolated melamine precondensates, such as those produced by BASF) with continuous stirring for 30 minutes at 35°C;

[0159] c. increasing the temperature to 60°C for 1 hour and then to 80°C for 1 hour, while maintaining stirring to obtain a suspension of microcapsules having a second shell of an aminoplast resin surrounding a first shell containing a polymer stabilizer;

[0160] d. Cooling the suspension to room temperature.

[0161] Example 4

[0162] In Example 4, microcapsules having a first shell containing a polymer stabilizer according to the present invention and a second shell based on polyurea were obtained by carrying out the following steps:

[0163] a. preparing microcapsules containing the polymeric stabilizer described in Example 1.6;

[0164] b. adding 2 g of a hydrodispersible isocyanate based on hexamethylene diisocyanate (Bayhydur® XP2547, Covestro) and 22 g of 4,4-dicyclohexylmethanediyl diisocyanate (Desmodur® W1, Covestro) to the emulsion, maintaining stirring of the system as in step (b) and (c) in Example 1, at a temperature of 35±2°C for 30 minutes;

[0165] c. adding 8 g of polyethyleneimine solution (Lupasol® G100 with a concentration of 35% (w / w) in deionized water, BASF) in one step and gradually heating the reaction mixture to 70°C for 2 h;

[0166] d. adding 12.5 g of a 40% (wt) aqueous solution of acrylic acid-diallyldimethylammonium chloride copolymer (Merquat 281, Lubrizol) and further heating the reaction mixture to 85°C for 2 h;

[0167] e. Add 410 g of ammonia solution and 3 g of hydroxyethyl cellulose (Natrosol™ 250HX, Ashland) and cool the mixture to room temperature;

[0168] f. Adjusting the final pH of the suspension to 4.0±0.2 using citric acid solution.

[0169] Example 5

[0170] Evaluation of microcapsule leakage in a model extraction medium

[0171] The model extraction medium was a system consisting of an aqueous solution of ethanol with an initial concentration of 30 vol.%, coexisting with an immiscible cyclohexane phase.

[0172] In the first stage, 10 ml of cyclohexane was placed in a vessel. Then, 1.8 ml of 30 vol.% ethanol in water was added to the vessel. After equilibration, taking into account that the distribution coefficient of ethanol between cyclohexane and water is 0.03, the percentage of ethanol in the aqueous phase was 25.2 ± 0.5 vol.%, and the percentage of ethanol calculated for the entire system was 2.4 ± 0.05 vol.%.

[0173] In the second step, the suspension to be studied was diluted so that the concentration of the perfume substance in the diluted suspension was approximately 10% (mass), and 200 microliters of this diluted suspension was added to the vessel.

[0174] In the third step, the vessel was subjected to horizontal stirring on an elliptical stirring equipment in the xy directions operating at 250 rpm for 4 h (shaking in the z direction was avoided).

[0175] In the fourth step, the upper cyclohexane phase containing the extracted perfume was analyzed spectrophotometrically using a UV / visible spectrometer. The perfume concentration was determined by measuring the absorbed UV / visible light intensity at the maximum absorption wavelength, which was previously determined using a perfume / cyclohexane standard sample solution of known concentration. This standard solution was used as an external standard for quantifying the extracted perfume. The leakage value was determined as the percentage of encapsulated perfume recovered in the hexane phase.

[0176] Typical leakage values ​​are given in Table 2 below.

[0177] Example 6

[0178] Evaluation of aroma release efficiency

[0179] The release efficiency of the microcapsule suspensions was measured using a texture analyzer (TA XT PLUS, manufactured by TA Instruments). Three hundred microliters of undiluted suspension were applied to the surface of filter paper in three 100-microliter batches and left to dry overnight. The bottom surface of a mechanical sensor, consisting of a flat metal cylinder with a diameter of 12.5 micrometers, was then applied to the deposited microcapsules at a penetration rate of 0.01 mm / s.

[0180] As the probe penetrates the microcapsule layer deposited on the filter paper, it experiences a force inverse to the elastic force, which is proportional to the microcapsule's flexural modulus, which is inversely proportional to the microcapsule release efficiency. The magnitude of the measured force at 50% deformation of the microcapsule layer is used as a measure of the microcapsule release efficiency. The displacement corresponding to the 50% deformation point is defined as the half-distance between the displacement point at which initial contact with the microcapsules occurs, which is marked by the occurrence of the reverse force, and the point at which the probe's movement is stopped by the filter paper.

[0181]

[0182] From the force at 50% deformation measured on the microcapsules of Example 1.4, it can be concluded that the shells containing the new polymer stabilizer are hard and have a measurable elastic modulus. This result, combined with the limited leakage in a model extraction environment, confirms that the encapsulating shell was effectively formed in this example. The values ​​for Example 1.6 confirm that the addition of additional aminosilane effectively improves both mechanical and leakage stability. The leakage values ​​for Examples 3 and 4 confirm the stabilizing effect of adding a second aminoplast shell. Finally, a comparison with prior art microcapsules containing conventional alkoxysilanes and aminopropyltriethoxysilane shows that the latter are much less leakage stable.

[0183] Example 7

[0184] Comparison of olfactory properties of novel and conventional silane-based microcapsules

[0185] The olfactory properties of the microcapsules of Examples 1.6, 3, and 4 according to the present invention were compared with the olfactory properties of the conventional silane-based microcapsules according to Example 2. The samples were evaluated in an unscented hair conditioner. The above-mentioned microcapsule suspensions were added to the hair conditioner formulation under gentle stirring with a paddle stirrer, so that the content of the suspension in the hair conditioner base was 1% (by weight) relative to the total weight of the hair conditioner base. 1.5 g of hair conditioner was applied to 15 g samples moistened with 12 g of water. The samples were massaged, left for 1 minute, and then rinsed for 30 seconds under running tap water at 37°C and a flow rate of 3.2 L / min without touching the samples with hands. Olfactory evaluation of the samples before grinding was performed after 4 hours. For this evaluation, the samples were handled carefully to minimize the risk of mechanical destruction of the microcapsules.Olfactory evaluation of the post-rubbing samples was performed after drying them for 24 hours at room temperature. This evaluation was conducted by gently rubbing one part of each sample. Olfactory properties (intensity) were rated by a panel of four experts on a scale of 1 to 5 (1 = barely noticeable, 2 = weak, 3 = moderate, 4 = strong, and 5 = very strong). Comments on the perceived odor direction were recorded, if necessary.

[0186] This evaluation was performed on fresh samples and on samples stored for 1 month at 37°C.

[0187]

[0188] The results show that the microcapsules according to the present invention provide a significant improvement in the properties of the perfume substance compared with conventional silane-based aminoplast microcapsules.

Claims

1. An encapsulated perfume composition comprising a core-shell microcapsule, wherein the core-shell microcapsule comprises a core containing at least one perfume ingredient, and a first shell surrounding the core, wherein the first shell comprises a polymeric stabilizer that is formed by combining a polymeric surfactant with at least one dipodal aminosilane, wherein the dipodal aminosilane is an aminosilane of formula (I) where X stands for -NR 1 -, -NR 1 -СН2-NR 1 -, -NR 1 -CH2-CH2-NR 1 -, NR 1 -CO-NR 1 - or each R 1 independently denotes H, CH3 or C2H5; each R 2 independently denotes a linear or branched alkylene group having from 1 to 6 carbon atoms; each R 3 independently denotes a linear or branched alkyl group having from 1 to 4 carbon atoms; each R 4 independently represents H or a linear or branched alkyl group having from 1 to 4 carbon atoms; f represents 0, 1, or 2; in which the polymeric surfactant contains anionic groups or groups that can form anions; and a second shell encapsulating the first shell, said second shell being formed by: - the reaction of an alkylated polyfunctional amine or the reaction of a polyfunctional amine with an aldehyde; or - interaction of a polyisocyanate with a polyfunctional amine.

2. The encapsulated composition of claim 1, wherein the dipodal aminosilane is selected from the group consisting of bis(3-(triethoxysilyl)propyl)amine, N,N'-bis(3-(trimethoxysilyl)propyl)urea, bis(3-(methyldiethoxysilyl)propyl)amine, N,N'-bis(3-(trimethoxysilyl)propyl)ethane-1,2-diamine, bis(3-(methyldimethoxysilyl)propyl)-N-methylamine and 1,4-bis(3-(triethoxysilyl)propyl)piperazine.

3. The encapsulated composition of claim 1, wherein the dipodal aminosilane is a secondary aminosilane.

4. An encapsulated composition according to any one of claims 1 to 3, wherein the polymeric stabilizer is formed by combining a polymeric surfactant with at least one dipodal aminosilane and an additional aminosilane, preferably an aromatic aminosilane, even more preferably selected from the group consisting of compounds having the formula II: where R 1denotes a linear or branched alkylene group having from 1 to 6 carbon atoms; each R 2 independently denotes a linear or branched alkyl group having from 1 to 4 carbon atoms; each R 3 independently represents H or a linear or branched alkyl group having from 1 to 4 carbon atoms; f denotes 0, 1, or 2.

5. The encapsulated composition of claim 4, wherein the aromatic aminosilane is selected from the group consisting of N-(3-(trimethoxysilyl)propyl)aniline and N-((trimethoxysilyl)methyl)aniline.

6. The encapsulated composition of any one of claims 1 to 5, wherein the anionic groups or groups that can form anions contained in the polymeric surfactant are selected from sulfate groups, sulfonate groups, phosphate groups, carboxylic acid groups, and anhydride groups.

7. An encapsulated composition according to any one of claims 1 to 6, wherein the polymeric surfactant is a copolymer of maleic anhydride with ethylene and / or vinyl methyl ether.

8. The encapsulated composition of claim 7, wherein the copolymer of maleic anhydride with ethylene and / or vinyl methyl ether is alternative.

9. An encapsulated composition according to claim 7 or 8, wherein the copolymer of maleic anhydride with ethylene and / or vinyl methyl ether is completely or partially hydrolyzed.

10. An encapsulated composition according to any one of claims 1 to 9, wherein the polymeric stabilizer is formed by a combination of bis(3-(triethoxysilyl)propyl)amine with (3-(trimethoxysilyl)propyl)aniline and a fully or partially hydrolyzed ethylene-maleic anhydride copolymer and / or a vinyl methyl ether-maleic anhydride copolymer, in particular in alternant form.

11. An encapsulated composition according to any one of claims 1 to 10, wherein the weight ratio of the dipodal aminosilane to the polymeric surfactant is from 0.02 to 1, preferably from 0.2 to 0.9, even more preferably from 0.3 to 0.

7.

12. An encapsulated composition according to any one of claims 5 to 11, wherein the weight ratio of the additional aminosilane to the polymeric surfactant is from 0.02 to 1, preferably from 0.1 to 0.7, even more preferably from 0.15 to 0.

5.

13. A method for producing an encapsulated composition according to any one of paragraphs 1-12, comprising the following steps: a. dissolution of the polymeric surfactant in the aqueous phase; b. dissolving at least one dipodal aminosilane in an oil phase containing at least one perfume ingredient; c. emulsifying the oil phase in the aqueous phase to form an oil-in-water emulsion; d. initiating a dipodal aminosilane and a polymeric surfactant to form a first shell of a polymeric stabilizer encapsulating the dispersed oil droplets, thereby forming a suspension of microcapsules, and e. provision - an alkylated polyfunctional amine or a polyfunctional amine and an aldehyde; or - polyisocyanate and polyfunctional amine, and initiating their interaction to form a second shell encapsulating the microcapsules formed in step d; where the dipodal aminosilane is an aminosilane of formula (I) where X stands for -NR 1 -, -NR 1 -СН2-NR 1 -, -NR 1 -CH2-CH2-NR 1 -, NR 1 -CO-NR 1 - or each R 1independently denotes H, CH3 or C2H5; each R 2 independently denotes a linear or branched alkylene group having from 1 to 6 carbon atoms; each R 3 independently denotes a linear or branched alkyl group having from 1 to 4 carbon atoms; each R 4 independently represents H or a linear or branched alkyl group having from 1 to 4 carbon atoms; f represents 0, 1, or 2; wherein the polymeric surfactant contains anionic groups or groups that can form anions.

14. A rinse-off consumer product comprising an encapsulated composition according to any one of claims 1-12, which is selected from the group consisting of detergents and fabric conditioners, hair conditioners, shampoos, liquid detergents for hard surfaces, cleaning agents for hard surfaces, laundry detergents, soaps, shower gels and skin care products.

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