JP2010275250A - Cosmetic - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cosmetic having an effective and continuing moisturizing effect. <P>SOLUTION: Biocompatible polymer nanoparticles which contain a moisturizing component and are surface-treated with a hydrophobicizing agent are incorporated into a cosmetic. As the moisturizing component, a ceramide or a ceramide precursor is suitably used and as the hydrophobicizing agent, a silicone is suitably used, and as the biocompatible polymer, a lactic acid-glycolic acid copolymer is suitably used. Further, such nanoparticles may be complex with a binder or the like. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a cosmetic having a moisturizing effect.

  Since the skin becomes easy to dry with age, the maintenance of the water retention capacity of the skin has been especially emphasized in recent years from the viewpoint of anti-aging, and various techniques for moisturizing have been studied.

  Various moisturizing ingredients such as hyaluronic acid and collagen are used in cosmetics. Among them, ceramide is a main component of keratin intercellular lipids and plays an important role in preventing moisture transpiration from the skin. Therefore, ceramide is used in many cosmetics as a moisturizing ingredient. A solid powder cosmetic containing powder and ceramide is known (Patent Document 1). In addition, it is known to use nanoparticles made of biocompatible polymer encapsulating ceramide as an external preparation composition (Patent Document 2). In addition to this, a hair growth agent for scalp that contains biocompatible polymer nanoparticles encapsulating stevia, ceramide precursor, ceramide, and blood flow promoting component is also known (Patent Document 3).

JP 2001-158717 A

Special table 2007-520576

JP 2009-107941 A

In order to fully exert the effect of the moisturizing component, if it is ceramide, it is necessary to deliver this to the stratum corneum cells of the stratum corneum, and if it is a moisturizing component other than ceramide (for example, hyaluronic acid or collagen) It is necessary to reach the dermis deeper than the layer. Moreover, in order to continuously exhibit the moisturizing effect, it is necessary to gradually release the moisturizing component. Furthermore, since many moisturizing ingredients are relatively expensive materials, an administration technique that exhibits a high moisturizing effect with a small amount of application is desirable.
However, if ceramide is simply blended as an oil component as in Patent Document 1, sufficient penetration into the stratum corneum cannot be expected due to surface tension and the like, and sustainability of the effect cannot be expected. Although these problems can be solved to some extent by using the biocompatible nanoparticles of Patent Document 2 and Patent Document 3, the biocompatible nanoparticles of Patent Document 3 for the purpose of blending into a hair restorer are disclosed in Patent Document 2. This biocompatible nanoparticle is not necessarily highly compatible with the skin because the particle surface is hydrophilic, and there is still room for improvement as a cosmetic composition.

  In view of the above problems, the present invention is to provide a cosmetic having an effective and continuous moisturizing effect.

  The first characteristic configuration of the cosmetic according to the present invention for achieving the above object lies in that biocompatible polymer nanoparticles containing a moisturizing component and surface-treated with a hydrophobizing agent are blended.

  By including the moisturizing component in the biocompatible polymer nanoparticles, the moisturizing component can reach the deep part of the skin, so that an effective moisturizing effect is exhibited. In addition, since the moisturizing component is continuously released by gradually decomposing the biocompatible polymer, a continuous moisturizing effect is exhibited. In addition, by surface-treating the biocompatible polymer nanoparticles with a hydrophobizing agent, the affinity with the skin is improved, and the particles that fall off the skin during application can be reduced. By these, the applied moisturizing component can be reliably delivered to the deep skin without waste, and a cosmetic having a high moisturizing effect can be provided even in a small amount. In the present invention, “nanoparticles” mean particles having an average particle diameter of less than 1000 nm.

  It is also expected that the secretion of sebum will be optimized as a result of enhancing the moisturizing effect by delivering the moisturizing component to the deep part of the skin. Since excessive secretion of sebum causes the break-up of makeup over time, it can be said that a cosmetic with enhanced moisturizing effect is also effective in preventing makeup break-up.

  The second characteristic configuration is that, in the first characteristic configuration, the moisturizing component is ceramide or a ceramide precursor.

  Ceramide or a ceramide precursor is a main component constituting intercellular lipids in the stratum corneum, and plays a role in preventing moisture evaporation from the inside of the skin. For this reason, by using ceramide or a ceramide precursor as a moisturizing component, it is possible to provide a cosmetic having an excellent moisturizing effect by enhancing the skin barrier function.

  The third characteristic configuration is that, in the first or second characteristic configuration, the hydrophobizing agent is silicone.

  Since silicone is excellent in stability in addition to hydrophobicity and skin affinity, by using silicone as a hydrophobizing agent, it is possible to provide cosmetics having excellent moisturizing effect and stable quality.

  The fourth characteristic configuration is that in any one of the first to third characteristic configurations, the biocompatible polymer is a lactic acid / glycolic acid copolymer.

  If a lactic acid / glycolic acid copolymer is used as the biocompatible polymer, the release rate of the encapsulated moisturizing component can be adjusted by controlling the ratio and molecular weight of lactic acid and glycolic acid. In addition, the lactic acid / glycolic acid copolymer has excellent long-term stability and can contain a relatively large amount of moisturizing components. Therefore, it is possible to provide a cosmetic with optimized moisturizing effect and stable quality.

  The cosmetic of the present invention contains biocompatible polymer nanoparticles encapsulating moisturizing ingredients and surface-treated with a hydrophobizing agent, so that the nanoparticles penetrate deep into the skin and gradually release the moisturizing ingredients. As a result, the moisturizing effect is demonstrated effectively and continuously, the affinity with the skin is improved, and the falling particles at the time of application can be reduced, so that the applied moisturizing component is reliably delivered to the deep part of the skin. Even if a small amount of moisturizing component, it exhibits a high moisturizing effect.

The schematic diagram of the ceramide inclusion | inner_cover nanoparticle which concerns on this invention. Furthermore, the schematic diagram of the nanoparticle which carry | supported ceramide. The schematic diagram of a ceramide inclusion composite particle. The graph which shows a moisture increase rate. The graph which shows TEWL suppression rate.

The nanoparticles of the present invention are those in which a moisturizing component is encapsulated in nanoparticles formed of a biocompatible polymer and surface-treated with a hydrophobizing agent (hereinafter may be described as “hydrophobized”). It is.
FIG. 1 is a schematic diagram showing the structure of nanoparticles according to the present invention. The hydrophobic moisturizing component-encapsulating nanoparticles 1 are formed by agglomerating a large number of biocompatible polymers 2, and the nanoparticles that are aggregates are surface-treated with a hydrophobizing agent 3. The matrix of the biocompatible polymer 2 contains a moisturizing component 4a.

  Examples of moisturizing ingredients used in the present invention include polyhydric alcohols (for example, 1,3-butylene glycol, dipropylene glycol, glycerin and the like), amino acids (glycosamine or salts thereof), sugar chains (for example, xylitol and the like), mucos. Polysaccharides (for example, hyaluronic acid or salts thereof), gums and carboxyvinyl polymers (acrylic acid / alkyl acrylate (C10-30) copolymers and other water-soluble polymers, organic acids or salts thereof, soybean lecithin, cholesterol Collagen and the like are preferred.

  Of these, ceramide is particularly suitable because it prevents moisture evaporation from the inside of the skin. Ceramide is a sphingolipid that occupies about 50% of interkeratinocyte lipids. It is known that there are seven types of ceramide 1 to ceramide 7 as the type and chemical structure of ceramide existing in the human stratum corneum. Ceramide is produced from serine and palmitoyl-CoA by the action of various enzymes, and once accumulated as glucosylceramide or sphingomyelin (ceramide precursor), it is discharged extracellularly at the bottom stratum corneum. Then, it is converted again into ceramide between keratinocytes by glucocerebrosidase or sphingomyelinase, and a layered structure (lamella structure) is constructed in which ceramide molecules are stacked together and stacked in a certain direction together with other intercellular lipids. And it is decomposed into sphingosine and fatty acid by ceramidase.

  The ceramide precursor is a substance that produces ceramide by metabolism in vivo, and includes glucosylceramide and sphingomyelin that are converted to ceramide, and glycosphingolipids extracted from animals and plants other than humans. Glycosphingolipids are those in which sugar is bound to ceramide, and include glucosylceramide bound to glucose and galactosylceramide bound to galactose. Ceramide dipotassium, ceramide stearyl and the like can also be suitably used.

  Biocompatible polymer nanoparticles penetrate deep into the skin, allowing the moisturizing component to reach the deep skin, and gradually decomposing the nanoparticles to release the moisturizing component in the deep skin. Can do.

By surface-treating the biocompatible polymer nanoparticles with a hydrophobizing agent, the affinity with the skin is improved. For this reason, the nanoparticles that fall off the skin when the cosmetic is applied can be reduced, and the applied moisturizing component can be surely penetrated deep into the skin without waste.
In addition, the surface treatment with a hydrophobizing agent can suppress an initial burst (a phenomenon in which a physiologically active ingredient is released at a time when the skin penetrates), so that a moisturizing component can be released continuously.
Furthermore, by increasing the affinity with the skin, the stretch of cosmetics and the familiarity with the skin are improved, and the feeling of use is improved.

The hydrophobizing agent used in the present invention is not particularly limited as long as the surface of the nanoparticles can be hydrophobized so as to enhance the affinity with the skin. Silicone, vegetable oil (castor oil, olive oil, etc.), fatty acid ester oil ( Butyl myristate, cetyl palmitate, triethylhexanoin, tri (capryl / capric acid) glyceryl, polyglyceryl-2 triisostearate, etc., higher alcohols (cetanol, stearyl alcohol, etc.), hydrocarbon oils (eg squalane), fluorine oil (Perfluoromethylisopropyl and the like) can be preferably used.
Among these, silicone that is excellent in stability in addition to hydrophobicity and skin affinity is particularly suitable.

Silicone is a polymer in which a siloxane bond composed of silicon and oxygen is used as a skeleton, an organic group mainly composed of methyl is bonded to silicon, and a silane monomer is hydrolyzed. Silicone includes octamethylpolysiloxane, tetradecamethylpolysiloxane, methylpolysiloxane, highly polymerized methylpolysiloxane, methylphenylpolysiloxane, methylhydrogenpolysiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, etc. And methylpolycyclosiloxane, trimethylsiloxysilicic acid, alkyl-modified silicone, polyether / alkyl-modified silicone, and alkylglyceryl ether-modified silicone.
Of these, methylpolysiloxane (dimethicone), decamethylcyclopentasiloxane (cyclopentasiloxane), methylhydrogenpolysiloxane (dimethicone / methicone copolymer) and the like are preferable.

The biocompatible polymer used in the present invention is desirably a biodegradable polymer that has low irritation and toxicity to the living body and is decomposed and metabolized after administration. Moreover, it is preferable that it is the particle | grains which discharge | release continuously the moisturizing component included.
Examples of such materials include polylactic acid (PLA), polyglycolic acid (PGA), polyaspartic acid and the like as biocompatible polymers. Further, these copolymers may be lactic acid / glycolic acid copolymer (PLGA), aspartic acid / lactic acid copolymer (PAL) or aspartic acid / lactic acid / glycolic acid copolymer (PALG). You may have such a charged group or group which can be functionalized.
Among these, a lactic acid / glycolic acid copolymer (PLGA) can be preferably used. It is known that PLGA can contain various physiologically active ingredients and can be stored for a long time while retaining the physiologically active ingredients. Furthermore, although depending on the type of physiologically active ingredient to be encapsulated and the molecular weight of PLGA, it is considered that sustained release can be performed in units of several hours to several months from the characteristics of PLGA hydrolysis and long-term half-life. In the cosmetic of the present invention, it is desirable to release the physiologically active ingredient in the range of 1 hour to 20 hours.

  The average molecular weight of PLGA is preferably in the range of 5,000 to 200,000, considering the ease of nanoparticle preparation, skin permeability of the prepared nanoparticles, and degradability inside the skin. More preferably, it is in the range of 15,000 to 25,000. The composition ratio of lactic acid to glycolic acid may be 1:99 to 99: 1, but is preferably 1/3 glycolic acid to lactic acid 1.

  Next, the manufacturing method of a moisturizing component inclusion nanoparticle is demonstrated. The method for producing the moisturizing component-encapsulating nanoparticles is not particularly limited as long as the moisturizing component and the biocompatible polymer can be processed into particles having an average particle diameter of less than 1,000 nm. Spherical crystallization can be preferably used. Spherical crystallization is a method in which spherical crystal particles can be designed and processed by directly controlling their physical properties by controlling the crystal generation and growth process in the final process of compound synthesis. One of the spherical crystallization methods is an emulsion solvent diffusion method (ESD method).

  The ESD method is a technique for producing nanoparticles (nanospheres) based on the following principle. In this method, two types of solvents are used: a good solvent that can dissolve the biocompatible polymer as a base material, and a poor solvent that does not dissolve the biocompatible polymer. As the good solvent, an organic solvent such as acetone that dissolves the biocompatible polymer and is miscible with the poor solvent is used. And as a poor solvent, water, polyvinyl alcohol aqueous solution, etc. are used normally. Hereinafter, the operation procedure when ceramide is used as the moisturizing component, PLGA is used as the biocompatible polymer, and silicone is used as the hydrophobizing agent will be described in detail. In some cases, a nanoparticle containing a moisturizing component is simply referred to as “nanoparticle”.

<Nanoparticle formation process>
First, after dissolving PLGA in a good solvent, a ceramide solution is added and mixed in the good solvent so that PLGA does not precipitate. When this mixed solution containing PLGA and ceramide is dropped into a poor solvent while stirring, the good solvent (organic solvent) in the mixed solution rapidly diffuses and moves into the poor solvent. As a result, self-emulsification of the good solvent occurs in the poor solvent (Marangoni effect), and emulsion droplets of the good solvent of submicron size are formed. Furthermore, due to the mutual diffusion of the good solvent and the poor solvent, the organic solvent continuously diffuses from the emulsion to the poor solvent, so that the solubility of PLGA and ceramide in the emulsion droplets decreases, and finally the ceramide is PLGA nanoparticles of encapsulated crystal particles are generated.

  In the above spherical crystallization method, nanoparticles can be formed by a physicochemical method, and the resulting nanoparticles are substantially spherical, so that homogeneous nanoparticles can be formed without considering the problem of catalyst and raw material residue. Can be easily formed. Then, the organic solvent which is a good solvent is depressurizingly distilled (solvent distillation process), and nanoparticle powder is obtained by drying.

  Although the kind of good solvent and poor solvent used in the nanoparticle formation step is not particularly limited, it is necessary to use a solvent that is highly safe for human bodies and has a low environmental load. As such a poor solvent, for example, water is preferably used. In order to enhance the dispersibility of the nanoparticles, an aqueous solution of a surfactant such as polyvinyl alcohol, polyethylene glycol, cyclodextrin, lecithin, hydroxymethyl cellulose, hydroxypropyl cellulose, or the like may be used.

  Examples of good solvents include halogenated alkanes, which are low-boiling organic solvents, acetone, methanol, ethanol, ethyl acetate, diethyl ether, cyclohexane, benzene, toluene, etc. About the guideline (March 30, 1998, Pharmaceutical Trial No. 307), only acetone classified as class 3 or a mixture of acetone and ethanol is preferably used.

  The ceramide-encapsulated nanoparticles produced in the present invention are not particularly limited as long as they have an average particle diameter of less than 1,000 nm, but generally the skin diameter is about 200 μm, so that the delivery effect to the stratum corneum is achieved. In order to increase the average particle size, the average particle size is preferably 300 nm or less. The skin cell size is 15,000 nm, and the skin cell spacing varies between shallow and deep skin, but is thought to be about 70 nm, and the skin cell spacing widens due to cell pulsation. If the diameter is about 200 nm, the nanoparticles can penetrate into the stratum corneum and further into the deep epidermis and dermis through the cell gap route (skin keratinocyte gap). On the other hand, if the particle size of the nanoparticles becomes too small, the amount of ceramide encapsulated decreases, so the average particle size is preferably 30 nm or more.

  The amount of ceramide encapsulated in the nanoparticles can be adjusted by adjusting the amount of ceramide added during nanoparticle formation, the type and molecular weight of the biocompatible polymer forming the nanoparticles, and the like. The amount of ceramide mixed in the good solvent during the formation of the nanoparticles is preferably 0.001 or more and 1.0 or less with respect to the biocompatible polymer. When the weight ratio with respect to the biocompatible polymer is less than 0.001, the concentration of ceramide in the good solvent is too low and the encapsulation rate in the nanoparticles is low. On the other hand, when it exceeds 1.0, formation of nanoparticles is inhibited.

  The ceramide-encapsulating nanoparticles can further support (externally attach) ceramide. Here, a method of electrostatically supporting ceramide on nanoparticles having a positive zeta potential will be described as an example.

  The surface of nanoparticles produced by spherical crystallization generally has a negative zeta potential. The zeta potential is a potential of a surface (sliding surface) where the above movement occurs when the potential of an electrically neutral region sufficiently separated from the particle is used as a reference. If the absolute value of the zeta potential is increased, the repulsive force between the particles is increased and the stability of the particles is increased. Conversely, as the zeta potential approaches 0, the particles are likely to aggregate. Therefore, the zeta potential is used as an index of the dispersed state of particles.

  In order to electrostatically support a ceramide having a negative zeta potential on a nanoparticle, it is necessary to charge the nanoparticle surface so as to have a positive zeta potential. When the cationic polymer is added to the poor solvent in the nanoparticle formation step, the surface of the formed nanoparticle is modified (coated) with the cationic polymer, and the zeta potential of the nanoparticle surface becomes positive. Therefore, by adding ceramide to the nanoparticle suspension before the hydrophobization treatment described later, a predetermined amount of ceramide that has become negatively charged anion molecules is supported on the nanoparticles by electrostatic interaction.

  Examples of the cationic polymer include chitosan and chitosan derivatives, cationized cellulose in which a plurality of cationic groups are bonded to cellulose, polyamino compounds such as polyethyleneimine, polyvinylamine, and polyallylamine, polyamino acids such as polyornithine and polylysine, and polyvinylimidazole. Polyvinylpyridinium chloride, alkylaminomethacrylate quaternary salt polymer (DAM), alkylaminomethacrylate quaternary salt / acrylamide copolymer (DAA), phospholipid polar group (phosphorylcholine group) that is a constituent of cell membrane (biological membrane) Polymers in which a cationic group such as a quaternary ammonium salt is bonded to a polymer having 2-methacryloyloxyethyl phosphorocholine (MPC) as a structural unit, which has both a methacryloyl group and an excellent polymerization property For example MPC and 2-hydroxy-3- methacryloyloxypropyl copolymer of trimethyl ammonium chloride) and others as mentioned, among others, chitosan or a derivative thereof is preferably used.

  Chitosan is a cationic natural polymer in which many glucosamines, one of the sugars with amino groups, contained in shrimp, crabs, and insect shells are bound. Emulsification stability, shape retention, biodegradability Since it has characteristics such as biocompatibility and antibacterial properties, it is widely used as a raw material for cosmetics, foods, clothing, pharmaceuticals and the like. By adding this chitosan into a poor solvent, ceramide-carrying nanoparticles with high safety and no adverse effects on the living body can be produced.

  FIG. 2 is a schematic diagram showing the structure of nanoparticles on which ceramide is electrostatically supported. The surface of the nanoparticles 1 is coated with a cationic polymer 5 and the outside thereof is surface-treated with a hydrophobizing agent 3. The cationic polymer 5 has a positive zeta potential. The ceramide 4 is encapsulated in the nanoparticles 1 (4a) and is electrostatically supported. In FIG. 2, ceramide supported on the nanoparticle surface is 4b.

  In addition, since the zeta potential becomes a larger positive value by using a more cationic polymer among the cationic polymers, more ceramide can be supported by the nanoparticles and the repulsive force between the nanoparticles is strong. As a result, the stability of the nanoparticles is increased. For example, a chitosan derivative such as N- [2-hydroxy-3- (trimethylammonio) propyl] chitosan having a higher cationic property by quaternizing a part of chitosan which is originally cationic ( Cationic chitosan) is preferably used.

  The amount of ceramide supported on the nanoparticles can be changed by adjusting the type and amount of the cationic polymer and the amount of ceramide added to the nanoparticle suspension before the hydrophobic treatment. The amount of ceramide added to the nanoparticle suspension is preferably 0.001 or more and 1.0 or less with respect to the biocompatible polymer. When the weight ratio with respect to the biocompatible polymer is less than 0.001, the concentration of ceramide is too low and the loading on the nanoparticles becomes low. On the other hand, when it exceeds 1.0, the amount that can be electrostatically supported is exceeded, and surplus ceramide that is not supported on the nanoparticles is generated.

  Thus, by combining the encapsulation of ceramide into nanoparticles and electrostatic loading, first the ceramide supported on the nanoparticles and then the ceramide encapsulated in the nanoparticles are released in this order. Therefore, the release rate of ceramide can be controlled in two stages.

  If surplus chitosan remains in the nanoparticle suspension before the hydrophobization treatment, chitosan and ceramide are adsorbed and ceramide cannot be efficiently supported on the nanoparticles. Therefore, it is preferable to provide a step (removal step) for removing chitosan by centrifugation before adding the ceramide solution after the solvent distillation step.

<Hydrophobicization treatment process>
In the ceramide-encapsulated nanoparticle suspension obtained in this manner, silicone previously dissolved in a water-miscible organic solvent such as alcohol is added with stirring, so that the surface layer of the nanoparticles is selectively used. Silicone is deposited and adsorbed on the surface. At this time, it is desirable that the weight ratio with respect to the biocompatible polymer is 0.001 or more and 20 or less as the amount of silicone added to the nanoparticle suspension. If it is less than 0.001, the hydrophobization of the nanoparticles becomes insufficient. On the other hand, if it exceeds 20, the aggregation between the nanoparticles becomes intense, and the adhesion to the inner wall of the reaction vessel, the stirring rod, the propeller, etc. increases. The yield of nanoparticles is also reduced.
As the water-miscible organic solvent for dissolving silicone, acetone, dimethyl sulfoxide, ethanol, methanol, isopropyl alcohol, and the like can be used, but the safety is particularly high and the solvent is distilled off at a low boiling point. Ethanol which is easy to do is suitable.

<Composite process>
The nanoparticles thus obtained are used as they are, or are combined as needed. This composite makes the composite particles easy to handle in which the nanoparticles are collected before use, and can return to the nanoparticles during use and restore their characteristics.

  As a nanoparticle composite method, a freeze drying method (for example, vacuum freeze drying using a drying shelf type freeze dryer (Takara Seisakusho) or Nauta mixer NXV (Hosokawa Micron)) is preferably used. It is done. Further, a fluidized bed dry granulation method (for example, fluid granulation is performed using Agromaster AGM (manufactured by Hosokawa Micron)) or a dry mechanical particle compounding method (for example, Mechanofusion System AMS (manufactured by Hosokawa Micron)) And may be combined by applying compressive and shear forces. In particular, when using a fluidized bed drying granulation method in which a mixture containing the material to be granulated is sprayed into a flowing gas, the composite particles can be easily and quickly reduced by shortening the time-consuming and laborious drying process. Since it can be manufactured, it is advantageous for industrialization.

  Next, composite particles obtained by combining ceramide-encapsulated nanoparticles with a binder will be described. By combining the nanoparticles with a binder, composite particles having excellent handling properties, redispersibility, and heat resistance can be obtained. Further, by adding a physiologically active ingredient in the binder, other physiologically active ingredients can be supported on the composite particles containing nanoparticles. FIG. 3 is a schematic diagram showing the structure of ceramide-containing composite particles obtained by combining ceramide-encapsulated nanoparticles with a binder. The composite particle 6 is a composite of the nanoparticle 1 with a binder 7, and a physiologically active component 8 is encapsulated in the binder 7.

  The binder can improve the heat resistance of the composite particles by forming a layer that separates the nanoparticles from each other at the time of compositing. In addition, if there is ceramide dispersed in the outer aqueous phase without being encapsulated in the nanoparticles, the ceramide dispersed in the outer aqueous phase is adsorbed on the surface of the nanoparticles during drying and forms a strong cross-link between the nanoparticles. Therefore, there is a concern that the redispersibility of the nanoparticles may be reduced. Therefore, by combining with a binder, it is possible to provide composite particles containing nanoparticles excellent in redispersibility, in which strong cross-linking between the nanoparticles is suppressed.

  Examples of such a binder include sugar alcohols such as mannitol, trehalose, sorbitol, erythritol, maltose, and xylitol, sucrose, and polymer compound powders such as an acrylic polymer and ethyl cellulose. If a sugar alcohol having a weak crystallinity is used as a binder, it may become amorphous during compounding and may not be formed into particles satisfactorily. Therefore, it is preferable to use mannitol having strong crystallinity.

  In addition, by encapsulating other physiologically active components in the binder, apart from ceramide released from the nanoparticles, the physiologically active components that dissolve from the surface of the composite particles immediately after permeation of the skin can be made to act immediately. . By adopting such a configuration, the composite particles can be given immediate effect.

  The physiologically active ingredients encapsulated in the binder include vitamin A, vitamin B, vitamin C, vitamin D, vitamin E, vitamin F, vitamin K, vitamin P, vitamin U, carnitine, ferulic acid, γ-oryzanol, α- Lipoic acid, orotic acid and their components or derivatives, retinol acetate, riboflavin acetate, pyridoxine dioctanoate, L-ascorbic acid dipalmitate, L-ascorbic acid-2-sodium sulfate, L-ascorbic acid phosphate Ester, DL-tocopherol-L-ascorbic acid diester dipotassium, pantothenyl ethyl ether, D-pantothenyl alcohol, acetyl pantothenyl ethyl ether, ergocalciferol, cholecalciferol, tocopherol acetate, tocopherol nicotinate Vitamin or vitamin derivatives such as roll, tocopherol succinate, or water-soluble pro such as VC-PMG (water-soluble ascorbyl phosphate Mg), AA2G (ascorbyl glucoside), panthenol (water-soluble vitamin B5), L-cysteine, etc. Vitamins are listed. Moreover, the moisturizing component included in the nanoparticles or a different moisturizing component may be used.

  By using the ceramide-encapsulated nanoparticles or ceramide-containing composite particles produced in this way as a raw material for cosmetics such as foundations, it has an effective and continuous moisturizing effect, and even with a small amount of moisturizing ingredients. A cosmetic that exhibits a sufficient moisturizing effect can be provided. The blending ratio of the nanoparticles or composite particles in the cosmetic can be arbitrarily set according to the required moisturizing effect.

  As a cosmetic dosage form, it is preferably used as a powder such as a powder foundation, but it may be used by blending it with an emulsion, lotion, skin cream or the like. In addition to powders, bases such as petrolatum, lanolin, paraffin, wax, plasters, resins, plastics, higher alcohols, glycols, glycerin, water, emulsifiers, suspending agents, etc. as necessary You may use it for the ointment, cream agent, lotion, gel agent etc. which were mix | blended and mixed. The blending ratio of the nanoparticles or composite particles in the cosmetic can be arbitrarily set according to the required effect, dosage form, and the like.

  In addition, PLGA will be hydrolyzed when it touches moisture for a long time, and the transport performance of nanoparticles will be lost. Therefore, when using as cosmetics such as milky lotion or lotion, or a lotion-type external preparation, the nanoparticle powder and the liquid in which it is dispersed are filled and stored in separate containers. It is preferable to mix and use a predetermined amount of the particle powder and the dispersion.

  In addition, the cosmetics of the present invention include talc, mica, sericite, titanium oxide, silicic anhydride, kaolin, zinc oxide, mica titanium, iron oxide and other inorganic powders, polyester, polyethylene, polystyrene, polyurethane, acrylic acid resin, Various resin powders such as phenol resin, fluororesin, divinylbenzene, styrene copolymer, or copolymer resin powders composed of two or more thereof, organic powders such as acetylcellulose, polysaccharides, proteins, red 202, red 226 Yellow 205, Yellow 401, Blue 1, Blue 204, Blue 404, etc. Pigment powder, metal soap such as zinc stearate, magnesium stearate, zinc palmitate, dimethicone, dimethicone / methicone copolymer, polyether Silicones such as modified silicones and fluorine-modified silicones, Lioctanoin, neopentyl glycol dicaprylate, tri (capryl / capric acid) glyceryl, (hydroxystearic acid / stearic acid / rosinic acid) dipentaerythrityl, ester oil such as hydrogenated isostearic acid castor oil, mineral oil, petroleum jelly, polybutene and other minerals Oils, carnauba wax, candelilla wax, beeswax and other waxes, jojoba oil, olive oil, aloe, safflower and other natural raw materials, etc. Alcohols such as polyhydric alcohols, surfactants, fats and oils, ultraviolet absorbers, colorants, fragrances, preservatives, and the like can be blended within a range that does not hinder the effects of the present invention.

The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and can be obtained by appropriately combining technical means disclosed in different embodiments. Embodiments are also included in the technical scope of the present invention. Hereinafter, the present invention will be described more specifically with reference to production examples, examples, comparative examples, and test examples. Hereinafter, composite particles of nanoparticles and a binder are described as “nanocomposite particles”.
[Production Example 1]

<Preparation of PLGA nanocomposite particles encapsulating ceramide and hydrophobized>
100 g of PLGA (PLGA-7520 manufactured by Wako Pure Chemical Industries, Ltd.) and 5 g of ceramide (Bioceramide CH manufactured by Yamakawa Trading Co., Ltd.) were dissolved in 2000 mL of acetone as a good solvent, and then 1000 mL of ethanol was added and mixed to obtain a polymer solution. This polymer solution was dropped into 4000 mL of water as a poor solvent at 40 ° C. and 400 rpm with stirring at a constant speed (20 mL / min), and ceramide-encapsulated PLGA nanoparticles were suspended by diffusion of the good solvent into the poor solvent. A liquid was obtained. Subsequently, after distilling off acetone and ethanol under reduced pressure, 500 mL of an ethanol solution in which 10 g of dimethicone / methicone copolymer (KF-9901 manufactured by Shin-Etsu Chemical Co., Ltd.), which is a kind of silicone, was dissolved was stirred at a constant rate (40 mL / min. ) To obtain a suspension of PLGA nanoparticles encapsulating ceramide and hydrophobized. Furthermore, 50 g of mannitol (manufactured by Towa Kasei Kogyo Co., Ltd.), a kind of sugar alcohol, was added to the resulting suspension, and then freeze-dried to form a composite. The obtained composite particles were sized using a sieve to obtain PLGA nanocomposite particle powder encapsulating ceramide and hydrophobized. Table 1 shows the weight ratio of each composition to the obtained nanocomposite particles. In addition, it was 182 nm when the nano composite particle was re-dispersed in water and the average particle diameter of the nanoparticle was measured with the particle size distribution measuring apparatus (Nikkiso Microtrac UPA) by a dynamic light scattering method.
[Production Example 2]

<Preparation of ceramide-encapsulated (not hydrophobized) PLGA nanocomposite particles>
PLGA nanocomposite particles encapsulating ceramide (not hydrophobized) were obtained in the same manner as in Production Example 1, except that the ethanol solution in which the dimethicone / methicone copolymer was dissolved was removed. Table 1 shows the weight ratio of each composition in the nanocomposite particles. The average particle size of the nanoparticles was 176 nm.

<Preparation of powder foundation>
The nanocomposite particles obtained in Production Example 1 and the components shown in A of Table 2 were mixed. To this mixture, the components shown in B of Table 1 were added and further mixed. The obtained mixture was sized with a sieve and then molded to prepare a powder foundation.

〔比較例１〕

[Comparative Example 1]

  A powder foundation was prepared in the same manner as in Example 1 except that the nanocomposite particles obtained in Production Example 2 were used instead of the nanocomposite particles obtained in Production Example 1. However, the compounding amount of the nanocomposite particles was adjusted so that the amount of ceramide in the foundation was equal to that in Production Example 1.

<Preparation of liquid foundation>
After mixing the components A and B shown in Table 3, the nanocomposite particles obtained in Production Example 1 were dispersed in the A phase and the B phase was gradually added dropwise with stirring. Finally, a liquid foundation was obtained by homogenization with a homogenizer.

〔比較例２〕

[Comparative Example 2]

In place of the nanocomposite particles obtained in Production Example 2 instead of the nanocomposite particles obtained in Production Example 1, the compounding amount was adjusted so that the amount of ceramide in the foundation was equal. A liquid foundation was prepared.
[Test Example 1]

Using 20 monitors, the powder foundations obtained in Example 1 and Comparative Example 1 were tested for use, sensory evaluation was performed on “moisturizing feeling”, “nobbling”, “attached”, and “decoration of makeup”, and the following criteria were used. The results are shown in Table 4.
(Criteria)
◎: 15 or more people judged good ○: 10 or more people, less than 15 judged good △: 5 people or more, less than 10 people judged good

〔試験例２〕

[Test Example 2]

    In the same manner as in Test Example 1, the liquid foundation obtained in Example 2 and Comparative Example 2 was tested for use, and a sensory evaluation was performed on “moisturizing feeling”, “feel”, “navi” and “decoration of makeup”. The results are shown in Table 5.

As shown in Table 4, when the powder foundation of Example 1 was used, most monitors judged that “moisturizing feeling”, “attached”, and “decoration of makeup” were better than when the powder foundation of Comparative Example 1 was used. did. Moreover, as shown in Table 5, when the liquid foundation of Example 2 was used, most of the monitors were related to “moisturizing feeling”, “feel”, and “decoration of makeup” compared to the case of using the liquid foundation of Comparative Example 2. Judged to be good.
[Test Example 3]

Before and after the implementation of Test Examples 1 and 2, the moisture value of the cheeks and transepidermal water loss (TEWL) values of each monitor were measured using a multi-skin measuring instrument (Courage + Khazaka MPA5), and the following formula From (1) moisture content increase rate and (2) TEWL value suppression rate were calculated. In addition, in order to evaluate a continuous moisturizing effect, the measurement after the test was performed 12 hours after using the foundation.

(1) Moisture increase rate (%) = (moisture value before test start-water value after test end) / water value before test start (2) TEWL suppression rate (%) = (TEWL value before test start− TEWL value after test) / TEWL value before test start

(1) The measurement result of the moisture increase rate is shown in FIG. 4, and (2) the measurement result of the TEWL suppression rate is shown in FIG. It can be seen that Example 1 significantly increased both (1) moisture increase rate and (2) TEWL suppression rate compared to Comparative Example 1 and Example 2 compared to Comparative Example 2.

  From these results, cosmetics containing ceramide, which is a moisturizing component, and blended with hydrophobized PLGA nanoparticles are uniformly moisturized when PLGA nanoparticles are uniformly fixed on the skin surface when applied to the skin. It has been confirmed that ceramide, which is a ceramide, is reliably delivered to the stratum corneum and is released continuously to exert an effective and persistent moisturizing effect.

  The cosmetic according to the present invention is effective and continuous, and can exhibit a high moisturizing effect. In addition, this makes it possible to optimize the secretion of sebum and prevent overtime makeup collapse. For this reason, besides being used suitably for a foundation, it can be used for a wide variety of dosage forms such as emulsion, lotion, skin cream, ointment, cream, lotion, gel.

1 Moisturizing component encapsulated nanoparticles 2 Biocompatible polymer (PLGA)
3 Hydrophobizing agent (silicone)
4a Moisturizing ingredient included (ceramide)
4b Moisturizing ingredient supported (ceramide)
5 Cationic polymer (chitosan)
6 Composite particle 7 Binder 8 Physiologically active ingredient

Claims (4)

  Cosmetics containing biocompatible polymer nanoparticles encapsulating moisturizing ingredients and surface-treated with a hydrophobizing agent.   The cosmetic according to claim 1, wherein the moisturizing component is ceramide or a ceramide precursor.   The cosmetic according to claim 1 or 2, wherein the hydrophobizing agent is silicone.   The cosmetic according to any one of claims 1 to 3, wherein the biocompatible polymer is a lactic acid / glycolic acid copolymer.

Images