Microcapsules and a cosmetic composition containing the same

Abstract

Disclosed are microcapsules comprising: (i) a core comprising a benefit agent; and (ii) a shell comprising silica, wherein the shell comprises a platy inorganic material having an average thickness of 1 to 1000 nm; and wherein the benefit agent is a fragrance, a pro-fragrance, a hair conditioning agent, an anti-dandruff agent, a moisturizer, an emollient, a dye and / or pigment, a color care additive (including a dye fixative), or a mixture thereof.

Description

[Technical Field]

[0001] The present invention relates to microcapsules and cosmetic compositions containing microcapsules. [Background technology]

[0002] Many personal and home care products strive to deliver beneficial agents to substrates such as hair, skin, fabrics, and hard surfaces. To achieve long-lasting performance, encapsulation of beneficial agents in microcapsules has been proposed as a means, particularly for fragrances. When applied, the microcapsules are deposited on a substrate, such as skin, and can be ruptured by the action of pressure and / or friction. The fragrance is then released, providing the consumer with a pleasant sensation.

[0003] However, there is still considerable room for improvement in consumer preference for improved fragrance perception at multiple stages of the washing process, such as the end of washing, and for more persistent and long-lasting fragrance performance, in order to drive commercial interest in this area.

[0004] Leakage of the encapsulating agent not only causes a decrease in performance but also presents the problem of limiting the materials that can be used as protective wall materials for the encapsulating agent. Melamine formaldehyde capsules are well known, but unfortunately, they need to be used in conjunction with a formaldehyde scavenger.

[0005] There is growing interest in developing safe and environmentally friendly microcapsules and compositions containing such microcapsule particles that deliver desired performance. U.S. Patent Application Publication No. 2016 / 177156A1 discloses a heat conduction capsule for increasing the thermal conductivity and heat capacity of heat exchange materials or similar thermal fluids. It can be used in cosmetic compositions and does not disclose any beneficial agents unrelated to the filling / release of beneficial agents. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] U.S. Patent Application Publication No. 2016 / 177156A1 [Overview of the project]

[0007] The inventors have developed microcapsules having a silica-containing shell with a beneficial agent in the core, the shell comprising a plate-like inorganic material having an average thickness of 1 to 1000 nM. Surprisingly, it has been found that such microcapsules, when included in cosmetic compositions, can have good filling efficiency and long-term sustained release of the beneficial agent while maintaining acceptable leakage for storage.

[0008] According to the first aspect, (i) A core containing beneficial agents, (ii) Microcapsules comprising a silica-containing shell, wherein the shell comprises a plate-like inorganic material having an average thickness of 1 to 1000 nm, and the beneficial agent is a fragrance, pro-fragrance, hair conditioning agent, anti-dandruff agent, moisturizer, emollient, dye and / or pigment, color care additive (including dye fixative), or a mixture thereof. Microcapsules are revealed.

[0009] According to a second aspect, a process for preparing microcapsules according to the first aspect of the present invention, a) A step of preparing an oil phase liquid containing a silica precursor and beneficial agents, b) A step of preparing an aqueous suspension by homogenizing a mixture of plate-shaped inorganic material and deionized water, c) A step of preparing an o / w emulsion by adding an aqueous suspension of plate-shaped inorganic material to an oil phase liquid and homogenizing it to form an emulsion, d) A step of placing the o / w emulsion in a 40°C oven for at least 24 hours to obtain a microcapsule slurry product, The process, including the following, will be disclosed.

[0010] According to a third aspect, a cosmetic composition comprising the microcapsules of the first aspect is disclosed. [Modes for carrying out the invention]

[0011] To avoid any doubt, any feature of one aspect of the present invention may be utilized in any other aspect of the present invention. The word “comprising” is intended to mean “including,” but not necessarily “consisting of” or “composed of.” In other words, the listed steps or options do not need to be exhaustive. Note that the examples given in the following description are intended to clarify the present invention and are not intended to limit the present invention to those examples themselves. Similarly, all percentages are weight / weight percentage unless otherwise specified. Except for the examples of operation and comparative examples, or unless explicitly stated, all figures in this description and claims indicating the amount of material or reaction conditions, the physical properties of the material, and / or use should be understood to be modified by the word “about.” Numerical ranges expressed in the form “x~y” are understood to include x and y. If multiple preferred ranges are described in the form “x~y” for a particular feature, it is understood that all ranges combining different endpoints are also intended. Where used herein, the indefinite articles "a" or "an" and their corresponding definite articles "the" mean at least one or more unless otherwise specified. The various features of the invention mentioned in the individual sections above are applied to other sections with the necessary modifications as needed. Thus, features specified in one section may be combined with features specified in other sections as needed. Any section headings are added for convenience only and are not intended to limit the disclosure in any way.

[0012] As used herein, "cosmetic composition" means a composition for topical application to the skin of mammals, particularly humans. Such compositions can generally be classified as leave-on or rinse-off, but are preferably of the leave-on type. The composition is specifically formulated into a product for application to the human body to improve appearance, but in addition, can also provide cleansing, odor control, or general aesthetic properties. The compositions of the present invention can be in the form of a liquid, lotion, cream, foam, scrub, gel, or toner, or can be applied via an instrument or a face mask or pad. Non-limiting examples of such compositions include leave-on skin lotions, creams, antiperspirants, deodorants, lipsticks, foundations, mascaras, sunless tanners, and sunscreen lotions. The compositions of the present invention are preferably leave-on compositions. As used herein, "skin" means the skin of the face as well as the body (e.g., neck, chest, back, arms, underarms, hands, legs, buttocks, and scalp), particularly the skin of those parts exposed to the sun.

[0013] As used herein, "hair care composition" means a composition for topical application to the hair or scalp of mammals, particularly humans. Topical means that the product is applied to the outer surface of the body. In the present invention, this is achieved by applying the hair care composition to the hair or scalp. Such products can generally be classified as leave-on or rinse-off and include any product applied to improve the appearance of the scalp and hair, cleansing, odor control, or general aesthetic properties. The hair care compositions of the present invention are preferably leave-on products. Alternatively, the hair care compositions of the present invention are rinse-off compositions. The hair care compositions according to the present invention are preferably shampoos, hair conditioners, hair creams, hair serums, mousses, hair gels, or hair oils.

[0014] "Length", "width", and "thickness" refer to the length, width, and thickness of non-aggregated particles or microcapsules. The term "length" typically refers to the average dimension of a particle or microcapsule along its longitudinal axis. The term "width" refers to the average dimension of a particle or microcapsule that is perpendicular to the length and typically perpendicular to the longitudinal axis. The term "thickness" refers to the average dimension of a particle or microcapsule that is perpendicular to both the length and the width. The length, width, and thickness can be measured, for example, by a scanning electron microscope (SEM) by averaging the values of at least 10 particles.

[0015] As used herein, "particle size" refers to the particle size in a non-aggregated state, unless otherwise specified. In the case of a polydisperse sample having fine particles with a diameter of 1 micron or less, the diameter means, for example, the z-average particle size measured using dynamic light scattering (see International Standard ISO 13321) using an instrument such as Zetasizer Nano (trademark) (Malvern Instruments ILtd, UK). In the case of a polydisperse sample having particles with a diameter exceeding 1 micron, the diameter means, for example, the apparent volume median diameter (D50, also known as x50 and sometimes d(0.5)) of the particles that can be measured by laser diffraction using a system (e.g., Mastersizer (trademark) 2000 available from Malvern Instruments Ltd) that meets the requirements described in ISO 13320.

[0016] According to a first aspect, (i) a core containing a beneficial agent, (ii) a shell containing silica, wherein the shell contains a plate-like inorganic material having an average thickness of 1 to 1000 nm, and the beneficial agent is a fragrance, a perfume, a hair conditioning agent, an anti-dandruff agent, a moisturizing agent, a skin softening agent, a dye and / or a pigment, a color care additive (including a dye fixative), or a mixture thereof, a microcapsule is disclosed.

[0017] The term microcapsule refers to core-shell microcapsules with a size range of preferably 0.5 to 100 microns, more preferably 2 to 50 microns, even more preferably 5 to 30 microns, and most preferably 5 to 20 microns.

[0018] The shell thickness is preferably 0.01 to 10 microns, more preferably 0.05 to 1 micron, and more preferably 0.1 to 0.3 microns.

[0019] Preferably, the microcapsules of the present invention are in the form of a powder or an aqueous suspension, more preferably in the form of an aqueous suspension. The aqueous form of such microcapsules preferably contains 1 to 90% by weight of microcapsules, with the remainder being water. Alternatively, the microcapsules are in the form of a powder, preferably a freeze-dried powder.

[0020] The shell of the microcapsule according to the present invention contains silica. Preferably, the silica is sufficiently dispersed in the shell and bonded to the plate-like inorganic material.

[0021] The core of the microcapsule according to the present invention preferably contains a thickening agent. The thickening agent may be a lipid that is solid at room temperature but liquefies upon heat, or a mineral that can absorb oil to increase viscosity. Preferably, the thickening agent may be a lipid selected from fatty alcohols, fatty acids, and waxes. Preferably, the thickening agent may be a mineral selected from silica, bentonite, and magnesium aluminum silicate. More preferably, the thickening agent is hydrophobic silica.

[0022] Plate-shaped inorganic materials The shell of the microcapsule according to the present invention also includes a plate-like inorganic material.

[0023] The inorganic material of the present invention is in the form of a plate and has an average thickness of 1 to 1000 nm, preferably 5 to 500 nm, more preferably 10 to 100 nm, and even more preferably 10 to 50 nm.

[0024] The average particle size of the inorganic material is preferably 10 to 2000 nm in diameter, more preferably 50 to 1000 nm, and most preferably 100 to 500 nm.

[0025] The inorganic material is preferably selected from MgAl layered double hydroxide, hydroxyapatite, diatomaceous earth, magnesium hydroxide, calcium hydroxide, zeolite MCM-22, boron nitride, or a combination thereof, and more preferably the inorganic material is MgAl layered double hydroxide.

[0026] The inorganic material is preferably anionically surface-modified. The anionically surface-modified inorganic material preferably contains a group selected from sulfates, hydrosulfites, hyposulfites, sulfites, bisulfites, carbonates, bicarbonates, hydroxyls, chlorates, perchlorates, chlorates, hypochlorites, chromates, chromites, dichromates, iodates, nitrates, nitrites, phosphates, hypophosphates, superphosphates, phosphates, hydrogen phosphates, dihydrogen phosphates, manganese, permanganate, thiosulfates, bisulfates, silicates, metasilicates, aluminosilicates, acetates, formates, oxalates, dioxalates, hydrogen sulfide, cyanates, thiocyanates, borides, chlorides, fluorides, iodides, borates, bromates, and hypobromites. Anionic surface-modified inorganic materials more preferably contain groups selected from sulfates, hydrosulfites, hyposulfites, sulfites, bisulfites, carbonates, bicarbonates, hydroxyls, chlorates, perchlorates, chlorates, hypochlorites, chromates, chromites, dichromates, phosphates, hypophosphites, superphosphates, phosphites, monohydrogen phosphates, dihydrogen phosphates, thiosulfates, bisulfates, silicates, metasilicates, aluminosilicates, acetates, formates, oxalates, dioxalates, and hydrogen sulfides. Anionic surface-modified inorganic materials more preferably contain sulfate groups.

[0027] The inorganic material most preferably contains an anionic surface-modified MgAl layered double hydroxide.

[0028] The inorganic material has multiple layers, and the interlayer distance is preferably 0.1 to 10 nm, more preferably 0.2 to 5 nm, and even more preferably 0.5 to 2 nm. The inorganic material is preferably 5 to 1000 m 2 / g, comfortable 10-500m 2 / g, more preferably 50-200m 2 It has a specific surface area of ​​ / g.

[0029] Beneficial agent The beneficial agent according to the present invention may refer to an agent that can provide a range of benefits to hair and / or scalp, more preferably to human hair. The beneficial agent is typically present in an amount of 10 to 90%, more preferably 30 to 80%, of the total weight of the microcapsules.

[0030] The beneficial agents of the present invention include fragrances, pro-fragrances, hair conditioning agents, anti-dandruff agents, moisturizers, emollients, dyes and / or pigments, color care additives (including dye fixatives), or mixtures thereof. More preferably, the beneficial agent includes fragrances, pro-fragrances, hair conditioning agents, anti-dandruff agents, or mixtures thereof. Even more preferably, the beneficial agent is selected from fragrances, pro-fragrances, or mixtures thereof, and most preferably, the beneficial agent is a fragrance.

[0031] Useful components of fragrances include both naturally derived and synthetic materials. These include single compounds and mixtures. Specific examples of such components can be found in current literature, for example, Fenaroli's Handbook of Flavour Ingredients, 1975, CRC Press; Synthetic Food Adjuncts, 1947, edited by Van Nostrand, by MB Jacobs; or Fragrance and Flavour Chemicals, 1969, Montclair, NJ (USA), by Arctander. These substances are well known to those skilled in the art of flavoring, fragrancing, and / or aromaticizing consumer products, that is, imparting odor and / or flavor or taste to traditionally fragranced or flavored consumer products, or modifying the odor and / or taste of consumer products.

[0032] In this context, "fragrance" refers not only to a fully formulated product fragrance, but also to the selected components of that fragrance, particularly the easily lost components such as the so-called "top notes."

[0033] Top notes are defined by Poucher (Journal of the Society of Cosmetic Chemists 6(2):80

[1955] ). Well-known examples of top notes include citrus oils, linalool, linalyl acetate, lavender, dihydromyrcenolate, rose oxide, and cis-3-hexanol. Top notes typically constitute 15–25% by weight of the fragrance composition, and in embodiments of the present invention containing increased levels of top notes, it is assumed that at least 20% by weight is present in the particles.

[0034] Another group of fragrances to which the present invention can be applied are so-called "aromatherapy" materials. These include many components also used in fragrances, including components of essential oils such as clary sage, eucalyptus, geranium, lavender, maize extract, neroli, nutmeg, spearmint, sweet violet leaf, and valerian.

[0035] Typical fragrance components that are advantageous to use in embodiments of the present invention include those having a relatively low boiling point, preferably less than 300°C when measured at one atmosphere, and preferably 100 to 250°C.

[0036] It is also advantageous to encapsulate fragrance components having a low LogP (i.e., the amount that is distributed in water), preferably less than 3.0.

[0037] Profragrances can be, for example, edible lipids. Edible lipids typically contain structural units that exhibit significant hydrophobicity. The majority of lipids are derived from fatty acids. In these "acyl" lipids, fatty acids exist mainly as esters and include mono-, di-, triacylglycerols, phospholipids, glycolipids, diol lipids, waxes, sterol esters, and tocopherols.

[0038] Fragrance typically makes up 10–85% of the total particle weight, preferably 15–75%. Fragrance appropriately has a molecular weight of 50–500 daltons. Pro-fragrance may have a higher molecular weight, typically 1–10 kD.

[0039] Pickering emulsion method: As used herein, “Pickering emulsion” refers to an emulsion stabilized by solid particles (e.g., colloidal silica) adsorbed at the interface between two phases. Pickering emulsion droplets are also suitable templates for microencapsulation and the formation of closed, impermeable capsules.

[0040] The present invention also relates to a process for preparing microcapsules.

[0041] The microcapsules according to the present invention are preferably prepared by using the Pickering emulsion method.

[0042] Microcapsule preparation process: The present invention also relates to a process for preparing microcapsules. The process is: a) A step of preparing an oil phase liquid containing a silica precursor and beneficial agents, b) A step of preparing an aqueous suspension by homogenizing a mixture of plate-shaped inorganic material and deionized water, c) A step of preparing an o / w emulsion by adding an aqueous suspension of plate-shaped inorganic material to an oil phase liquid and homogenizing it to form an emulsion, d) The step of placing the o / w emulsion in an oven at 40°C for at least 24 hours to obtain a microcapsule slurry product.

[0043] The silica precursor is preferably selected from alkoxysilanes and water-soluble silicates. Preferably, the alkoxysilane is selected from tetraethyl orthosilicate, tetramethyl orthosilicate, methyltriethoxysilane, methyltrimethoxysilane, vinyltrimethoxysilane, 3-aminopropyltrimethoxysilane, aminopropyltriethoxysilane, or a mixture thereof. More preferably, the alkoxysilane is selected from tetraethyl orthosilicate, aminopropyltriethoxysilane, or a mixture thereof.

[0044] The oil phase liquid in step a) preferably contains a thickener that increases the viscosity of the oil phase liquid. The thickener may be a lipid that is solid at room temperature but liquefies upon heat, or a mineral that can absorb oil and increase viscosity. Preferably, the thickener may be a lipid selected from fatty alcohols, fatty acids, and waxes. Preferably, the thickener may be a mineral selected from silica, bentonite, and magnesium aluminum silicate. More preferably, the thickener is hydrophobic silica.

[0045] It is preferable that ammonia be introduced into the aqueous suspension in step b).

[0046] Cosmetic composition In a further embodiment, a cosmetic composition is disclosed comprising microcapsules of the first embodiment in a carrier acceptable as a cosmetic. The cosmetic composition preferably contains 0.001% to 10%, more preferably 0.005% to 7.55%, and most preferably 0.01% to 5% by weight of microcapsules, based on the total weight of the composition.

[0047] Various materials may be present in the composition containing the microcapsules of the present invention in order to function as a carrier acceptable for use in cosmetics.

[0048] Preferably, the carrier contains water. The amount of water may range from 1 to 85% by weight, more preferably 5 to 90%, even more preferably 35 to 80%, and optimally 40 to 70%, based on the weight of the cosmetic composition, depending on the properties of the composition. Preferably, the carrier contains a surfactant.

[0049] The cosmetic compositions of the present invention may further contain other components common in the art to enhance their physical properties and performance. Suitable components include, but are not limited to, binders, colorants and pigments, pH adjusters, preservatives, optics, fragrances, viscosity modifiers, biological additives, buffers, conditioners, beneficial agents including natural extracts, essential oils and anti-inflammatory agents, coolants, antiperspirants, anti-aging agents, acne inhibitors, anti-dandruff agents, hair conditioning agents, antimicrobial agents, and antioxidants.

[0050] The cosmetic compositions of the present invention are suitable for topical application to human skin, scalp / hair, and include leave-on and wash-off products. Preferably, the compositions of the present invention are wash-off compositions. More preferably, the cosmetic compositions of the present invention are hair care compositions.

[0051] Hair care composition Preferably, the hair care product is a shampoo, hair conditioner, hair cream, hair serum, mousse, hair gel, or hair oil.

[0052] The hair care composition according to the present invention may also contain an anti-dandruff agent. The hair care composition of the present invention preferably contains 0.05 to 5% by weight of an anti-dandruff agent. The anti-dandruff agent is a compound active against dandruff, and is typically an antibacterial agent, preferably an antifungal agent. The antifungal agent typically exhibits a minimum inhibitory concentration of about 50 mg / ml or less against Malassezia species.

[0053] The anti-dandruff agent is preferably selected from azoles, Octopirox® (piroctone olamine), selenium sulfide, salicylic acid, and combinations thereof. Azoles include ketoconazole and crimbazole, preferably crimbazole.

[0054] The hair care composition of the present invention may further contain a zinc salt. The additional zinc salt may be appropriately selected from zinc salts of organic acids, zinc salts of inorganic acids, zinc oxide, zinc hydroxide, or mixtures thereof.

[0055] Preferred zinc salts include zinc oxide, zinc pyrrolidonecarboxylate, zinc citrate, zinc carbonate, zinc chloride, zinc sulfate, zinc glycinate, zinc acetate, zinc lactate, and mixtures thereof. Where present, the hair care composition of the present invention preferably contains 0.1 to 5% by weight, preferably 0.2 to 3% by weight, and more preferably 0.25 to 2.5% by weight of the salt, based on the total weight of the composition.

[0056] The hair care composition of the present invention comprises a surfactant selected from the group consisting of anionic surfactants, nonionic surfactants, zwitterionic surfactants, and mixtures thereof. The properties, types, amounts, and specific combinations that can be used depend on the formulation of the composition and, more importantly, on whether it is a shampoo, conditioner, or conditioning shampoo.

[0057] Preferably, the hair care composition of the present invention is a shampoo. Preferably, it contains a surfactant which is sodium lauryl sulfate, sodium lauryl ether sulfate, sodium lauryl ether sulfosuccinate, ammonium lauryl sulfate, ammonium lauryl ether sulfate, sodium cocoyl isethionate and lauryl ether carboxylic acid, cocobetaine, cocamidopropyl betaine, sodium cocoamphoacetate, or a mixture thereof.

[0058] Preferably, the hair care composition of the present invention contains 1 to 50%, preferably 2 to 40%, and more preferably 4 to 25% of total surfactants.

[0059] The hair care composition of the present invention is more preferably to contain cosmetic ingredients. Preferably, the cosmetic ingredients are selected from the group consisting of silicones, antimicrobial agents other than anti-dandruff agents, foaming agents, fragrances, encapsulating agents (e.g., encapsulated fragrances), dyes, colorants, pigments, preservatives, thickeners, proteins, phosphate esters, buffers, pH adjusters, pearlescent agents (e.g., mica, titanium dioxide, titanium dioxide-coated mica, ethylene glycol distearate (INCI glycol distearate)) and / or opacifiers, viscosity modifiers, emollients, sunscreens, emulsifiers, sensing active substances (e.g., menthol and menthol derivatives), vitamins, mineral oils, essential oils, lipids, natural active substances, glycerin, plant extracts, fruit extracts, natural hair nutrients such as sugar derivatives and amino acids, microcrystalline cellulose, and mixtures thereof.

[0060] Preferably, the hair care composition of the present invention contains at least one cosmetic ingredient in an amount of 0.01 to 20% by weight, more preferably 0.05 to 10% by weight, even more preferably 0.075 to 7.5% by weight, and most preferably 0.1 to 5% by weight, based on the weight of the total composition.

[0061] The hair care compositions of the present invention may also include synergistic antimicrobial compounds that, when used in combination with anti-dandruff active substances (e.g., zinc pyrithione), enhance their properties and provide synergistic antimicrobial benefits by further inhibiting the growth of Malassezia furfur. Non-limiting examples of these compounds include compounds having an alcohol group (e.g., honokiol, magnolol, or paeonol), piperazines, and phenolic compounds found in natural plant extracts, namely thymol and terpeniols.

[0062] Hair care products may further contain vitamin B3 compounds. A preferred vitamin B3 compound is niacinamide.

[0063] Niacinamide is known to stimulate the secretion of AMP (antimicrobial protein) from keratinocytes. This secreted AMP provides, for example, improved scalp immunity. Therefore, the anti-dandruff effect of niacinamide can be enhanced not only by its antifungal activity, but also by strengthening the scalp's own protective shield against pathogens. This combination can provide even longer-lasting protection, such as up to 24 hours of protection against bacteria.

[0064] If present, the hair care composition of the present invention preferably contains 0.1 to 5% niacinamide by weight of the composition, more preferably 0.5 to 5%, even more preferably 0.5 to 3%, and optimally 1.0 to 3.0% niacinamide.

[0065] silicone The hair care composition of the present invention preferably contains silicone.

[0066] For example, the composition of the present invention may contain emulsified droplets of a silicone conditioning agent to enhance conditioning performance.

[0067] Suitable silicones include polydiorganosiloxanes and polydimethylsiloxanes having the CTFA designation dimethicone. In addition, polydimethylsiloxanes having hydroxyl-terminated groups with the CTFA designation dimethiconol are suitable for use in the compositions of the present invention (particularly shampoos and conditioners).

[0068] Preferably, the viscosity of the emulsified silicone is at least 10,000 cst at 25°C, and the viscosity of the silicone is preferably at least 60,000 cst, most preferably at least 500,000 cst, and ideally at least 1,000,000 cst. Preferably, the viscosity is 10 to facilitate formulation. 9 It will not exceed CST.

[0069] Examples of suitable pre-formed emulsions include Xiameter MEM 1785 and microemulsion DC2-1865, available from Dow Corning. These are dimethiconol emulsions / microemulsions. Cross-linked silicone gums are also available in pre-emulsified forms, which is advantageous for facilitating formulation. A more preferred class of silicones for inclusion in shampoos and conditioners is amino-functional silicone. "Amino-functional silicone" means a silicone containing at least one primary, secondary, or tertiary amine group, or a quaternary ammonium group. Examples of suitable amino-functional silicones include the polysiloxane "amodimethicone" with the CTFA designation.

[0070] Specific examples of amino-functional silicones suitable for use in the present invention are aminosilicone oils DC2-8220, DC2-8166, and DC2-8566 (all manufactured by Dow Corning).

[0071] The total amount of silicone is preferably 0.01 to 10% by weight, more preferably 0.1 to 5% by weight, and most preferably 0.5 to 3% by weight.

[0072] shampoo If the hair care product of the present invention is a shampoo, it is generally aqueous, that is, it has water or an aqueous solution or a lyotropic liquid crystal phase as its main component.

[0073] Ideally, the shampoo composition should contain 50-98%, preferably 60-92%, of water.

[0074] Preferably, the shampoo composition contains one or more cationic polymers for conditioning the hair.

[0075] Suitable cationic polymers include homopolymers that are cation-substituted or can be formed from two or more types of monomers. The weight-average (M) of the polymer.w The molecular weight is generally between 100,000 and 3,000,000 Daltons. The polymer has cationic nitrogen-containing groups such as quaternary ammonium or protonated amino groups, or mixtures thereof. If the molecular weight of the polymer is too low, the conditioning effect will be insufficient. If it is too high, there may be problems with high extensional viscosity, which leads to stringiness of the composition when injected.

[0076] Cationic nitrogen-containing groups generally exist as substituents on a portion of the total monomer units of cationic polymers. Therefore, if the polymer is not a homopolymer, it can contain spacer non-cationic monomer units. Such polymers are listed in the CTFA Cosmetic Ingredient Directory, 3rd edition. The ratio of cationic to non-cationic monomer units is generally selected to give a polymer with a required cationic charge density, typically between 0.2 and 3.0 meq / gM. The cationic charge density of the polymer is appropriately determined under chemical testing for nitrogen determination by the Kjeldahl method described in the United States Pharmacopeia.

[0077] Suitable cationic polymers include copolymers of vinyl monomers having cationic amines or quaternary ammonium functional groups with water-soluble spacer monomers, such as (meth)acrylamide, alkyl and dialkyl(meth)acrylamide, alkyl(meth)acrylate, vinylcaprolactone, and vinylpyrrolidine. The alkyl and dialkyl-substituted monomers preferably have C1-C7 alkyl groups, more preferably C1-3 alkyl groups. Other suitable spacers include vinyl esters, vinyl alcohols, maleic anhydride, propylene glycol, and ethylene glycol.

[0078] Cationic amines can be primary, secondary, or tertiary amines, depending on the specific species and pH of the composition. Generally, secondary and tertiary amines, particularly tertiary amines, are preferred.

[0079] Amine-substituted vinyl monomers and amines can be polymerized in amine form and then converted to ammonium by quaternization.

[0080] Cationic polymers may contain mixtures of monomer units derived from amines and / or quaternary ammonium-substituted monomers and / or compatible spacer monomers.

[0081] Suitable (non-limiting) cationic polymers include: - For example, cationic diallyl quaternary ammonium-containing polymers, including dimethyldiallylammonium chloride homopolymers and copolymers of acrylamide and dimethyldiallylammonium chloride, which are referred to as polyquaternium-6 and polyquaternium-7 in the Industrial Convention on Faculties (CTFA), respectively; - Mineral salts of amino-alkyl esters of homopolymers and copolymers of unsaturated carboxylic acids having 3 to 5 carbon atoms (as described in U.S. Patent No. 4,009,256); - Cationic polyacrylamide (described in International Publication No. 95 / 22311).

[0082] Other cationic polymers that can be used include cationic polysaccharide polymers such as cationic cellulose derivatives, cationic starch derivatives, and cationic guar gum derivatives.

[0083] Particularly suitable types of cationic polysaccharide polymers that can be used are cationic guar gum derivatives, such as guar hydroxypropyltrimethylammonium chloride (commercially available from Rhodia under their JAGUAR trademark series). Examples of such materials are JAGUAR C13S, JAGUAR C14, and JAGUAR C17.

[0084] A mixture of any of the above cationic polymers may be used.

[0085] The hair care composition of the present invention preferably contains 0.01 to 5%, preferably 0.02 to 1%, and more preferably 0.05 to 0.8% of a cationic polymer.

[0086] The hair care composition of the present invention has an average molecular weight (M) of 1 million to 2.2 million g / mol. w The material may further contain a cationic deposition polymer which is a cationic polygalactomannan having a degree of cationic substitution of 0.13 to 0.3.

[0087] Polygalactomannans are polysaccharides composed primarily of galactose and mannose units and are typically found in the endomilk material of seeds from leguminous plants such as guar, locust bean, honey locust, flame tree, and other members of the Fabaceae family. Polygalactomannans consist of a backbone of 1→4 linked β-D-mannopyranosyl backbone units (also called mannoside units or residues) and repeating 1→6 linked α-D-galactosyl side chain groups (also called galactoside units or residues) branching from the 6th carbon atom of mannopyranose residues in the polymer backbone. Polygalactomannans from different leguminous species differ from each other in the frequency of galactoside side units branching from the polymannoside backbone. Mannoside and galactoside units are collectively referred to as glycoside units or residues herein. The average ratio of mannoside to galactoside units in polygalactomannan (hereinafter referred to as "guar") contained in guar gum is approximately 2:1.

[0088] Suitable cationic polygalactomannans include guar and hydroxyalkyl guar (e.g., hydroxyethyl guar or hydroxypropyl guar) that have been cationically modified by chemical reaction with one or more derivatizing agents.

[0089] In a typical composition, the amount of cationic polygalactomannan is generally in the range of about 0.05 to 1%, preferably 0.1 to 0.8%, and more preferably 0.2 to 0.6%, based on the weight of the composition.

[0090] The hair care product of the present invention may further contain an anionic polymer rheology modifier such as a carboxylic acid polymer.

[0091] In the context of the present invention, the term "carboxylic acid polymer" generally refers to a homopolymer or copolymer obtained from the polymerization of an ethylenically unsaturated monomer containing a pendant carboxylic acid group (hereinafter referred to as "carboxyl monomer").

[0092] A suitable carboxymonomer generally has one or two carboxylic acid groups, one carbon-to-carbon double bond, and contains a total of 3 to about 10 carbon atoms, more preferably 3 to about 5 carbon atoms.

[0093] Specific examples of suitable carboxymonomers include α-β-unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid; as well as α-β-unsaturated dicarboxylic acids such as itaconic acid, fumaric acid, maleic acid, and aconitic acid. Salts, esters, or anhydrides of the above α-β-unsaturated mono- or dicarboxylic acids may also be used. Examples include α-β-unsaturated dicarboxylic acids and monomethyl fumarates. 1-4 Half-esters with alkanols; cyclic anhydrides of α-β-unsaturated dicarboxylic acids such as maleic anhydride, itaconic anhydride, and citraconic anhydride; and C acrylates with acrylic acid or methacrylic acid such as ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, hexadecyl acrylate, and octadecyl acrylate. 1-30 It contains esters with alkanols.

[0094] In some cases, other ethylenically unsaturated monomers can be copolymerized into the carboxylic acid polymer backbone. Examples of such other ethylenically unsaturated monomers include styrene, vinyl acetate, ethylene, butadiene, acrylonitrile, and mixtures thereof. The carboxylic acid polymer may preferably have a molecular weight of at least 1 million daltons.

[0095] A suitable example is C1-4 It contains a crosslinked copolymer polymerized from an alkyl acrylate or methacrylate (e.g., ethyl acrylate) and one or more comonomers selected from acrylic acid, methacrylic acid, and mixtures thereof. Such materials can generally be referred to by the INCI name of the acrylate copolymer. Commercial examples include Aculyn® 33 manufactured by Rohm and Haas.

[0096] C of acrylic acid or methacrylic acid 10-30 Alkyl esters, and crosslinked copolymers polymerized from one or more comonomers selected from acrylic acid, methacrylic acid, and their respective C 1-4 Alkyl esters are also suitable. Such materials can generally be referred to by the INCI name of Acrylates / C10-30 Alkyl Acrylate Crosspolymer. Commercial examples include Carbopol® polymers 1342 and 1382 manufactured by Lubrizol Advanced Materials.

[0097] Copolymers that may be crosslinked with acrylic acid or methacrylic acid, alkyl acrylate, and ethoxylated hydrophobic modified alkyl acrylate are also suitable. Such materials can generally be referred to by the INCI names of acrylate / steareth-20 methacrylate copolymer, acrylate / beheneth-25 methacrylate copolymer, acrylate / steareth-20 methacrylate crosspolymer, and acrylate / palmiteth-25 acrylate copolymer. Commercial examples include Aculyn® 22, 28, or 88 manufactured by Rohm&Haas and Synthalen® manufactured by 3V Sigma.

[0098] The carboxylic acid is preferably a carbomer such as a homopolymer of acrylic acid crosslinked with allyl ether of pentaerythritol or allyl ether of sucrose.

[0099] Mixtures of any of the above materials can also be used.

[0100] Preferably, the hair care composition of the present invention contains 0.1 to 3.0%, more preferably 0.4 to 1.5%, of the weight of the composition, of a carboxylic acid polymer.

[0101] In formulations containing anionic polymer rheology modifiers such as the carboxylic acid polymers described above, it is often necessary to neutralize at least some of the free carboxyl groups by adding an inorganic or organic base. Suitable examples of inorganic or organic bases include alkali metal hydroxides (e.g., sodium hydroxide or potassium hydroxide), sodium carbonate, ammonium hydroxide, methylamine, diethylamine, trimethylamine, monoethanolamine, triethanolamine, and mixtures thereof.

[0102] The hair care composition of the present invention may also include a nonionic polymer rheology modifier selected from one or more nonionic cellulose ethers.

[0103] Suitable nonionic cellulose ethers or nonionic polymer rheology modifiers in this invention include methylcellulose and ethylcellulose (C 1-3 Alkyl)cellulose ethers; hydroxyethylcellulose and hydroxypropylcellulose, etc. 1-3 Alkyl)cellulose ether; mixed hydroxy(C) cellulose such as hydroxyethylhydroxypropylcellulose. 1-3 Alkyl)cellulose ethers; as well as (C) methylcellulose and hydroxypropylmethylcellulose. 1-3 Alkyl)hydroxy(C 1-3 It contains alkyl cellulose ether.

[0104] In the present invention, preferred nonionic cellulose ethers for use as nonionic polymer rheology modifiers are water-soluble nonionic cellulose ethers such as methylcellulose and hydroxypropylmethylcellulose. In this context, the term "water-soluble" refers to solubility in at least 1 gram, more preferably at least 3 grams, and most preferably at least 5 grams of water in 100 grams of distilled water at 25°C and 1 atm. This level indicates the formation of a macroscopically isotropic or clear, colored, or colorless solution.

[0105] Methylcellulose and hydroxypropylmethylcellulose are commercially available from Dow Chemical in several viscosity grades under their METHOCEL® trademark series.

[0106] Any mixture of nonionic cellulose ethers may also be suitable. In a typical composition according to the present invention, the level of nonionic cellulose ether is generally in the range of about 0.01 to about 2.0% by weight based on the total weight of the composition, preferably in the range of 0.1 to 0.5%, and more preferably in the range of 0.1 to 0.3%.

[0107] Preferably, the hair care product of the present invention contains 0.1 to 0.3% by weight of nonionic cellulose ether.

[0108] The hair care composition of the present invention may contain further optional ingredients to enhance performance and / or consumer acceptability. Examples of such ingredients include fragrances, dyes and pigments, as well as preservatives. Each of these ingredients is present in an amount effective to achieve its purpose. Generally, these optional ingredients are included individually at a level of up to 5% by weight, based on the total weight of the composition.

[0109] Usage Mode The cosmetic composition of the present invention is primarily intended for topical application to the skin, scalp, and hair.

[0110] The present invention also provides a method for processing a substrate, comprising the step of processing the substrate with a composition comprising the microcapsules of the present invention. Preferably, the substrate is skin, hair, and / or scalp. More preferably, the substrate is hair and / or scalp.

[0111] The cosmetic composition is preferably a hair care composition, and if the hair care composition is a shampoo, it is applied topically to the hair and then massaged into the hair and scalp. It is then rinsed with water before drying the hair. A leave-on hair care composition, such as a hair oil or hair serum, is applied and left on for 1 to 10 hours before being rinsed off.

[0112] The present invention is further illustrated by the following non-limiting embodiments, and unless otherwise specified, all percentages cited are weight-based on total weight.

[0113] The present invention is not limited to the embodiments shown in the drawings. Therefore, if a reference number follows a feature described in the claims, it should be understood that such numbering is included solely for the purpose of clarifying the claims and is not intended to limit them in any way.

[0114] The examples are intended to illustrate the present invention and are not intended to limit the present invention to those examples themselves. [Examples]

[0115] [Table 1]

[0116] Other chemicals used in the examples were obtained from Sinopharm Chemical Reagent Co., Ltd.

[0117] [Example 1] Preparation of internal microcapsules according to the present invention. (1) Preparation of plate-shaped MgAl-LDH material: Mg(NO3)2.6H2O (0.0115 mol, 5.128 g), Al(NO3)3.9H2O (0.005 mol, 3.751 g), and hexamethylenetetramine (0.026 mol, 3.645 g) were mixed with 80 ml of deionized water, and the mixture was magnetically stirred until all chemicals were completely dissolved. The solution was transferred to an autoclave and heated at 140°C for 24 hours. The mixture in the autoclave was then separated into a 10 ml plastic centrifuge tube, and the crude product was obtained by centrifugation. The crude product was then washed with ethanol solution (ethanol:deionized water = 1:1 v / v) at a stirring speed of 4 krpm for 3 minutes, and the supernatant was discarded after centrifugation. The washing / centrifugation process was repeated three times, and finally the product was dried in an oven at 50°C.

[0118] (2) Preparation of plate-shaped SDS (sodium dodecylsulfonate) modified MgAl-LDH material: The preparation process was the same as that for the MgAl-LDH material (see above), except that sodium dodecylsulfonate (0.0052 mol, 1.498 g) was added during the mixing step.

[0119] (3) Preparation of microcapsules using MgAl-LDH material as a stabilizer: a) Preparation of oil phase (A): 0.5 ml of tetraethyl orthosilicate and 0.05 ml of aminopropyltriethoxysilane were mixed with 2 ml of limonene, and the mixture was shaken until completely homogeneous. In some cases, 0.034 g of hydrophobic SiO2 was added to the mixture to increase the viscosity of the oil phase. b) Preparation of emulsifier solution (B): 0.4 g of MgAl-LDH particles (or SDS-modified MgAl-LDH particles) were added to 20 ml of deionized water, and the mixture was homogenized at 3 krpm for 30 seconds. In some cases, 0.25 ml of ammonia was added to the mixture to accelerate the reaction rate of shell formation. c) Next, solution B was added to liquid A, and the mixture was homogenized at 8 krpm for 3 minutes to form an emulsion. d) Next, the emulsion was placed in an oven at 40°C for at least 24 hours to obtain the microcapsule slurry product.

[0120] (4) Characterization of the prepared microcapsules: The morphology of the MgAl-LDH material was characterized using a transmission electron microscope (TEM, JEOL JEM-2011) at 200kV. X-ray powder diffraction (XRD) analysis was performed using a BRUKER D2-PHASER X-ray diffractometer with CuKα rays (l=0.15418nm) over a 2θ range of 10° to 70° at a scanning rate of 4 / min. The morphology of the microcapsule samples was characterized using a scanning electron microscope (SEM, PHENOM PROX) or observed using a microscope (LTD XSP-3C with Shanghai Precision Instrument co. 20× objective lens). Microcapsule size was evaluated using the particle size measured by Mastersizer 2000.

[0121] To further test the strength of the shells, the fragrance was removed from the microcapsules by washing the aqueous suspension with ethanol. The strength of the microcapsules can be evaluated by observing whether or not the microcapsule structure collapsed after ethanol treatment. If the microcapsule shells remain intact even after ethanol treatment, the shell strength is considered very good.

[0122] The microcapsules of the present invention prepared by the above method were observed under a microscope, and a summary can be found in Table 1 below.

[0123] [Table 2]

[0124] As can be seen from Table 1, the microcapsules of the present invention (numbers 1-4) could be formed using the Pickering emulsion method. It also shows that the thickness of the plate-like inorganic material can be reduced for anionic surface modification, which helps stabilize the emulsion, and thereby the formed microcapsules are more intact. It has also been found that if the core contains a thickener for the oil phase liquid (e.g., silica), microcapsules of better quality can be formed.

[0125] Furthermore, it has been found that the shell of microcapsule (reference number 4) may remain intact even after ethanol treatment, indicating that the strength of the shell of microcapsule (reference number 4) is higher than that of others. The thickness of the shell was approximately 100-300 nm.

[0126] [Example 2] Fragrance filling efficiency and filling rate of the microcapsules of the present invention (taking reference number 4 as an example) A typical procedure was described as follows: 0.5 ml of microcapsule (reference number 4) slurry was mixed with 2 ml of deionized water while gently stirring with a glass rod. The diluted slurry was then filtered using a syringe-driven filter (0.45 μm, polyethersulfone membrane, ANPEL Scientific Instrument Co., Ltd.) to remove the microcapsules. The filtrate was mixed with 4 ml of ethanol in a 20 ml vial. The amount of fragrance in the filtrate (unfilled fragrance) was evaluated using GC-FID, and the data was W u This was recorded as follows. In another case, 0.5 ml of microcapsule slurry was mixed with 2 ml of deionized water. Then, 1.0 ml of diluted slurry and 4.0 ml of ethanol were added to a 20 ml vial. The vial was sealed and vibrated at 1000 rpm for 1 minute on an IKA MS2 Minishaker. The amount of fragrance in the slurry (total fragrance) was evaluated using GC-FID, and the data was recorded in W T It was recorded as follows. Next, the fragrance filling efficiency can be calculated according to the following formula. Fragrance filling efficiency % = (WT -W U ) / W T *100 (formula 1) During the ceremony, W T = Total weight of fragrance W U = Weight of unfilled fragrance In addition, the fragrance filling rate can also be calculated according to the following formula. Fragrance filling rate %=(W T -W U ) / (W s +W T -W U )*100 (formula 2) During the ceremony, W s = This represents the weight of the capsule shell, which was calculated according to the supply of raw materials for shell formation. The data is summarized in Table 2.

[0127] [Table 3]

[0128] As shown in Table 2, no unfilled fragrance was detected, indicating a fragrance filling efficiency close to 100%. Subsequently, the fragrance filling rate was calculated as 74%. Therefore, the fragrance filling efficiency and filling rate of the microcapsules of the present invention are very good.

[0129] [Example 3] Leakage of fragrance from the microcapsules of the present invention (taking reference number 4 as an example) in a pharmaceutical formulation. Simplified body wash formulations (fragrance-free) are shown in Table 3.

[0130] [Table 4]

[0131] A typical procedure for evaluating fragrance leakage was described as follows: A 40 mg microcapsule (reference number 4) (400 mg microcapsule slurry, approximately 10% solids, 74% fragrance filling rate) was placed in a 20 ml vial, and 3 ml of body wash formulation was added to achieve a final fragrance concentration of approximately 10 mg / ml. The vial was sealed and the formulation and capsules were thoroughly mixed by vibrating it on an IKA MS2 Minishaker at 1000 rpm for 1.5 minutes. The vial was then allowed to stand at room temperature for 2, 4, or 24 hours. The mixture was then diluted approximately 10-fold by mixing with 36 ml of deionized water, and the capsules were removed by filtration using a syringe-driven filter (0.45 μm, polyethersulfone membrane, ANPEL Scientific Instrument Co., Ltd.). The purpose of dilution is to reduce the viscosity of the formulation sample and facilitate filtration. Next, 2 ml of the above filtrate was placed in a 20 ml vial and mixed with 8 ml of ethanol (to ensure that the fragrance concentration was within the range of the predetermined calibration curve for GC-FID evaluation), and the amount of fragrance in the filtrate (fragrance leakage) was evaluated using GC-FID. The data is summarized in Table 4.

[0132] [Table 5]

[0133] The data in Table 4 shows that the leakage rate was 20-30% during 24-hour storage, and no significant increase in leakage was observed with increasing storage time. Therefore, the leakage of the prepared fragrance capsules is at an acceptable level.

[0134] [Example 4] Fragrance release from the microcapsules of the present invention (taking reference number 4 as an example). A typical procedure for evaluating fragrance release was described below: A microcapsule sample (reference number 4) was prepared by placing 100 μl of microcapsule slurry into a 20 ml vial. The vial (without a cap) was left standing in a fume hood at room temperature (25°C) for 0, 1, 2, 3, 4, 5, or 6 hours. A control sample was prepared by mixing 1.0 g of limonene, 2.3 g of Tween-40, and 10.0 g of deionized water together. The limonene and Tween-40 content in the control sample was 7.5% and 17.3%, respectively. 100 μl of the control sample was placed into a 20 ml vial, and the vial (without a cap) was left standing in a fume hood at room temperature (25°C) for 0, 1, 2, 3, 4, 5, or 6 hours. Then, 5 ml of ethanol was added to the vial containing the capsule sample or control sample, and the vial was sealed. Next, the vial was vibrated on an IKA MS2 Minishaker at 1000 rpm for 60 seconds. The amount of fragrance in the ethanol (fragrance that was not released) was evaluated using GC-FID. The data is summarized in Table 5.

[0135] [Table 6]

[0136] The data in Table 5 shows that nearly 100% of the fragrance was released from the control sample within 3 hours, while only about 60% of the fragrance was released from the capsule sample within 6 hours. Therefore, this demonstrates the long-term sustained release characteristics of the microcapsules of the present invention.

Claims

1. A microcapsule, (i) a core comprising a benefit agent; (ii) a shell comprising silica; Including, the shell comprises a plate-like inorganic material having an average thickness of 1 to 1000 nm; Microcapsules wherein the benefit agent is a fragrance, a pro-fragrance, a hair conditioning agent, an anti-dandruff agent, a moisturizer, an emollient, a dye and / or pigment, a color care additive (including a dye fixative), or a mixture thereof.

2. 2. The microcapsule according to claim 1, wherein the average particle diameter of the plate-like inorganic material is 10 to 2000 nm.

3. 3. The microcapsules according to claim 1, wherein the plate-like inorganic material is selected from the group consisting of MgAl layered double hydroxide, hydroxyapatite, diatomaceous earth, magnesium hydroxide, calcium hydroxide, zeolite MCM-22, and boron nitride.

4. The microcapsules according to any one of claims 1 to 3, wherein the plate-like inorganic material is a MgAl layered double hydroxide.

5. The microcapsule according to any one of claims 1 to 4, wherein the plate-like inorganic material is anionically surface-modified.

6. The plate-like inorganic material has a length of 5 to 1000 m ２ The microcapsules according to any one of claims 1 to 5, having a specific surface area of ​​0.1g / g.

7. 7. The microcapsule of any one of claims 1 to 6, wherein the benefit agent is selected from a fragrance, a pro-fragrance, or a mixture thereof.

8. 8. The microcapsule of claim 1, wherein the core comprises a thickener.

9. 9. Microcapsules according to any one of claims 1 to 8, wherein the microcapsules have an average particle size of 0.5 to 100 microns.

10. 10. Microcapsules according to any one of claims 1 to 9, wherein the microcapsules are in the form of an aqueous suspension.

11. A method for producing the microcapsules according to any one of claims 1 to 10, a) preparing an oil phase liquid comprising a silica precursor and a benefit agent; b) preparing an aqueous suspension by homogenizing a mixture of platelet-shaped inorganic material and deionized water; c) preparing an oil-in-water emulsion by adding an aqueous suspension of plate-like inorganic material to the oil phase liquid and homogenizing to form an emulsion; d) placing the oil-in-water emulsion in an oven at 40°C for at least 24 hours to obtain a microcapsule slurry product; A manufacturing method comprising:

12. A cosmetic composition comprising the microcapsules of any one of claims 1 to 10 in a cosmetically acceptable carrier.

13. The composition of claim 12 comprising a surfactant.

14. 14. The composition of claim 12 or 13, which is a wash-off product.

15. The composition according to any one of claims 12 to 14, which is a hair care composition.