Scalp and hair improvement agent

Abstract

This scalp and hair improvement agent includes a composition containing a lipid film structure formed by a phospholipid having an acid value of at least 5 mg KOH / g.

Description

Scalp and hair improvement agent

[0001] The present invention relates to a scalp hair improving agent that forms a lipid membrane structure containing a specific phospholipid.

[0002] In modern society, where beauty and health are highly valued, improving hair quality and scalp health have become important concerns for many people. Hair firmness and body are elements that symbolize healthy, youthful hair, and improving their quality has a significant impact on a person's self-confidence and appearance. Furthermore, scalp health is directly related to hair health, and preventing dandruff, in particular, is one of the basic measures for avoiding scalp problems. Conventional technologies have developed a wide variety of shampoos, rinses, and treatments to improve hair texture and maintain scalp cleanliness. These products offer certain benefits, such as cleansing power from surfactants and moisturizing effects from plant-derived ingredients. However, these conventional products can cause scalp irritation and excessive strain on the hair with long-term use. Liposomes, lipid membrane structures primarily composed of phospholipids, have been known to be useful in skin care (see Patent Document 1).

[0003] Patent No. 6778306

[0004] As mentioned above, it is known that lipid membrane structures mainly composed of phospholipids are useful for skin care as a carrier of active ingredients, but their effects as scalp hair improving agents, such as improving hair firmness, improving hair stiffness, improving scalp moisture, and preventing scalp dandruff, are not known.In view of the above circumstances, the problem that the present invention aims to solve is to provide a scalp hair improving agent that improves or prevents hair troubles such as improving hair firmness and hair stiffness, and scalp troubles such as moisturizing scalp and preventing scalp dandruff, without relying on special treatments or drugs, and with little burden on sensitive hair and scalp, safely.

[0005] As a result of extensive research, the inventors discovered that the above problems can be solved by using a lipid membrane structure formed from a phospholipid having a specific acid value as a scalp hair improvement agent, and thus completed the present invention.

[0006] That is, the present invention is as follows. [1] A scalp hair improvement agent comprising a composition containing a lipid membrane structure formed from a phospholipid having an acid value of 5 mg KOH / g or more. [2] The scalp hair improvement agent according to [1] above, wherein the phospholipid is a hydrogenated phospholipid. [3] The scalp hair improvement agent according to [1] or [2] above, wherein the lipid membrane structure is a single lamellar structure. [4] The scalp hair improvement agent according to [1] or [2] above, wherein the lipid membrane structure has an average hydrodynamic diameter of 200 nm or less. [5] The scalp hair improvement agent according to [1] or [2] above, which has an effect of improving hair firmness. [6] The scalp hair improvement agent according to [1] or [2] above, which has an effect of improving hair strength. [7] The scalp hair improvement agent according to [1] or [2] above, which has an effect of improving hair luster. [8] The scalp hair improvement agent according to [1] or [2] above, which has an effect of improving hair gloss. [9] The scalp hair improvement agent according to [1] or [2] above, which has a hair moisture-retaining improving effect.

[10] The scalp hair improvement agent according to [1] or [2] above, which has a hair-waviness reducing effect.

[11] The scalp hair improvement agent according to [1] or [2] above, which has a split-end preventing effect.

[12] The scalp hair improvement agent according to [1] or [2] above, which has a color fade suppressing effect.

[13] The scalp hair improvement agent according to [1] or [2] above, which has a bed-head preventing effect.

[14] The scalp hair improvement agent according to [1] or [2] above, which has a bed-head eliminating effect.

[15] The scalp hair improvement agent according to [1] or [2] above, which has a hair surface repair effect.

[16] The scalp hair improvement agent according to [1] or [2] above, which has a scalp moisture-retaining improving effect.

[17] The scalp hair improvement agent according to the above [1] or [2], which has a scalp dandruff prevention effect.

[18] The scalp hair improvement agent according to the above [1] or [2], which has a scalp itching improvement effect.

[19] The scalp hair improvement agent according to the above [1] or [2], which has a scalp inflammation suppression effect.

[20] The scalp hair improvement agent according to the above [1] or [2], which has a scalp odor suppression effect.

[21] The scalp hair improvement agent according to the above [1] or [2], which has a hair growth effect.

[22] The scalp hair improvement agent according to the above [1] or [2], which has a hair growth effect.

[23] The scalp and hair improvement agent according to the above [1] or [2], which has an effect of improving gray hair.

[0007] The present invention can provide a scalp and hair improving agent that improves or prevents hair troubles such as loss of hair firmness and strength, scalp troubles such as scalp moisturization and prevention of scalp dandruff, safely with little burden on sensitive hair and scalp, without relying on special treatments or chemicals.

[0008] 1 is a photograph of the lipid membrane structure formed in Example 5, observed by cryo-TEM.

[0009] Hereinafter, a mode for carrying out the present invention (hereinafter also referred to as "the present embodiment") will be described in detail. Note that the present invention is not limited to the present embodiment, and various modifications can be made within the scope of the gist of the present invention.

[0010] The scalp hair improvement agent of the present embodiment is a scalp hair improvement agent comprising a composition containing a lipid membrane structure formed from a phospholipid having an acid value of 5 mgKOH / g or more (hereinafter also referred to as a "lipid membrane structure-containing composition").

[0011] As used herein, "lipid membrane structures" refers to particles having a lamellar (lipid bilayer) structure in which lipid molecules are arranged with their hydrophilic groups facing outward and their hydrophobic groups facing each other. Specific forms thereof include those described in the section <Lipid membrane structure-containing composition> below. Furthermore, as used herein, if the mean hydrodynamic diameter of a lipid membrane structure-containing composition prepared using a composition for forming lipid membrane structures can be measured using a dynamic light scattering measurement device, more specifically, a Zetasizer Nano ZSP (manufactured by Malvern Instruments), it is considered that lipid membrane structures have been formed.

[0012] <Composition for forming lipid membrane structures> The composition for forming lipid membrane structures in this embodiment is a composition for obtaining a lipid membrane structure-containing composition. The components of the composition for forming lipid membrane structures will be described below.

[0013] [Component (A)] The composition for forming a lipid membrane structure in this embodiment contains, as component (A), a phospholipid having an acid value of 5 mgKOH / g or more. The phospholipid having an acid value of 5 mgKOH / g or more may be one or more types, or may be a combination of one or more phospholipids with an acid value of less than 5 mgKOH / g and one or more phospholipids with an acid value of 5 mgKOH / g or more, with an acid value of 5 mgKOH / g or more.

[0014] The origin of the phospholipid is not particularly limited, but lecithin is particularly preferred because it is naturally derived and can be suitably used in cosmetics and scalp and hair external preparations.The lecithin may be derived from soybean, egg yolk, rapeseed, sunflower, corn, etc., and is preferably derived from plants such as soybean, rapeseed, sunflower, corn, etc., and is more preferably derived from soybean in view of easy availability and quality stability.

[0015] The phospholipid is preferably a hydrogenated phospholipid from the viewpoints of preventing oxidative deterioration due to heating processes in the production of cosmetics and quasi-drugs, oxidative deterioration during storage of these products, preventing accelerated oxidation of lipids in the stratum corneum and keratinocytes around the scalp due to oxidative deterioration of phospholipids and their lipid membrane structures, maintaining and strengthening the structure of stratum corneum intercellular lipids (barrier function) when the lipid membrane structures penetrate deep into the stratum corneum after application, strengthening the barrier function of the lipid membrane structures remaining on the stratum corneum surface that form on the scalp, and repairing and strengthening the structure of hair surface and deep hair. Hydrogenated phospholipids can be obtained by adding hydrogen atoms to the unsaturated carbon bonds of phospholipids using conventionally known methods. Hydrogenated lecithin is particularly preferred as the hydrogenated phospholipid.

[0016] The acid value of the phospholipid used in this embodiment is 5 mgKOH / g or more. When a phospholipid with an acid value of less than 5 mgKOH / g is used, the dispersibility of the lipid membrane structure deteriorates, and sufficient scalp hair improvement effect cannot be obtained. From the viewpoint of obtaining a finer lipid membrane structure, the acid value of the phospholipid is preferably 6, 7, 8, 9, 10, or 11 mgKOH / g or more, more preferably 12, 13, or 14 mgKOH / g or more, even more preferably 15 or 16 mgKOH / g or more, still more preferably 17, 18, or 19 mgKOH / g or more, particularly preferably 20 or 21 mgKOH / g or more, and particularly preferably 22, 23, 24, 25, 26, or 27 mgKOH / g or more. The upper limit of the acid value of the phospholipid is not particularly limited, and is, for example, 70 mgKOH / g or less, 60 mgKOH / g or less, 50 mgKOH / g or less, or 40 mgKOH / g or less. By appropriately selecting the type of phospholipid, a phospholipid having a desired acid value can be obtained. The acid value of the phospholipid is determined in accordance with "Standards for Quasi-drug Ingredients 2021, General Test Methods, Part 28. Acid Value Measurement Method."

[0017] The phospholipid may be either a synthetic product or a commercially available product. Examples of commercially available products include EMALEX (registered trademark) SLP manufactured by Nippon Emulsion Co., Ltd. and SLP-White H manufactured by Tsuji Oil Mills Co., Ltd. These may be used alone or in combination of two or more types.

[0018] The content of phospholipid in the composition for forming a lipid membrane structure in this embodiment is not particularly limited, but the lower limit is preferably 5% by mass or more, and more preferably 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, or 19% by mass or more. The upper limit is preferably 50% by mass or less, and more preferably 45, 40, 35, 30, 25, or 20% by mass or less. When the phospholipid content is 5% by mass or more, lipid membrane structures are efficiently formed when the composition for forming a lipid membrane structure is dispersed in water, and a sufficient scalp hair improvement effect tends to be obtained. When the phospholipid content is 50% by mass or less, component (A) is more easily dissolved or dispersed in the composition for forming a lipid membrane structure. Therefore, by using the composition for forming a lipid membrane structure, lipid membrane structures with excellent dispersibility in an aqueous phase are easily formed, and the stability of the lipid membrane structure-containing composition over time tends to be improved.

[0019] [Component (B)] The composition for forming a lipid membrane structure in this embodiment may contain, as component (B), a compound represented by the following formula 1. The component (B) may be one type or two or more types.

[0020]

[0021] In the above formula 1, R is a substituted or unsubstituted alkyl group having 2 to 6 carbon atoms or a substituted or unsubstituted cycloalkyl group having 3 to 6 carbon atoms.

[0022] The alkyl group having 2 to 6 carbon atoms may be either linear or branched. Examples of the alkyl group having 2 to 6 carbon atoms include an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an iso-amyl group, a tert-pentyl group, a neopentyl group, an n-hexyl group, a 3-methylpentan-2-yl group, a 3-methylpentan-3-yl group, a 4-methylpentyl group, a 4-methylpentan-2-yl group, a 1,3-dimethylbutyl group, a 3,3-dimethylbutyl group, and a 3,3-dimethylbutan-2-yl group. The alkyl group having 2 to 6 carbon atoms is preferably linear. That is, the alkyl group having 2 to 6 carbon atoms is preferably a group selected from the group consisting of an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, and an n-hexyl group.

[0023] Examples of the cycloalkyl group having 3 to 6 carbon atoms include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group, and preferably a cyclohexyl group.

[0024] Substituents for the alkyl group having 2 to 6 carbon atoms and the cycloalkyl group having 3 to 6 carbon atoms are not particularly limited as long as they do not impair the effects of the present invention. Examples of the substituents include halogen atoms, acyl groups, alkyl groups, aryl groups, alkoxyl groups, nitro groups, amino groups, and cyano groups. However, alkyl groups having 2 to 6 carbon atoms are not substituted with alkyl groups.

[0025] In the above formula 1, X is —O—, —C(═O)O—, or —O—C(═O)—, and is preferably —O—. Furthermore, in the above formula 1, n is 0 or 1. In the above formula 1, when X is —O— and n is 1, the number of carbon atoms in the alkyl group represented by R is preferably 4 or more.

[0026] The component (B) is preferably at least one selected from the group consisting of, for example, 1,2-pentanediol, 1,2-hexanediol, 1,2-heptanediol, 1,2-octanediol, cyclohexylglycerin, and hexylglycerin.

[0027] In particular, when 1,2-hexanediol, 1,2-heptanediol, or hexylglycerin is used as component (B), extremely fine lipid membrane structures can be formed. In this case, the lipid membrane structures are thought to form bicelles. Because bicelles are disc-shaped monolamellar structures, they have superior permeability to the stratum corneum of the scalp and hair compared to liposomes of comparable particle size. Therefore, from the perspective of obtaining lipid membrane structures with high permeability for fat-soluble components, it is preferable to use at least one selected from the group consisting of 1,2-hexanediol, 1,2-heptanediol, and hexylglycerin as component (B).

[0028] The component (B) may be either a synthetic product or a commercially available product.

[0029] The content of component (B) in the composition for forming a lipid membrane structure of this embodiment is not particularly limited, but the lower limit is preferably 15% by mass or more, and more preferably 20, 25, 30, 35, 40, 45, or 50% by mass or more, and the upper limit is preferably 95% by mass or less, more preferably 90, 85, 80, 75, or 70% by mass or less, and even more preferably 65, 60, or 55% by mass or less.

[0030] In the composition for forming lipid membrane structures of this embodiment, the content of component (B) preferably exceeds 100 parts by mass per 100 parts by mass of component (A). When the content of component (B) exceeds 100 parts by mass per 100 parts by mass of component (A), it tends to be easier to form fine lipid membrane structures. Furthermore, the content of component (B) is preferably 110, 120, 130, 140, or 150 parts by mass or more per 100 parts by mass of component (A). When the content is 150 parts by mass or more, component (A) is more easily dissolved or dispersed in the composition for forming lipid membrane structures, and therefore, by using this composition for forming lipid membrane structures, it tends to be possible to form lipid membrane structures with excellent dispersibility in an aqueous phase. Furthermore, from the viewpoint of obtaining finer lipid membrane structures, the content of component (B) is preferably 160, 170, 180, 190, or 200 parts by mass or more, more preferably 210, 220, 230, 240, or 250 parts by mass or more, even more preferably 260, 270, 280, 290, or 300 parts by mass or more, still more preferably 310, 320, 330, 340, or 350 parts by mass or more, and particularly preferably 360, 370, 380, 390, or 400 parts by mass or more, per 100 parts by mass of component (A). On the other hand, although there is no particular upper limit to the content of component (B) per 100 parts by mass of component (A), even if it exceeds 2000 parts by mass, the solubility or dispersibility of component (A) in the composition for forming lipid membrane structures is minimally affected, making it uneconomical. Therefore, according to this embodiment, the content of component (B) is preferably 2000 parts by mass or less per 100 parts by mass of component (A). Therefore, according to this embodiment, the content of component (B) is preferably more than 100 parts by mass and 2000 parts by mass or less per 100 parts by mass of component (A).

[0031] [Component (C)] The composition for forming a lipid membrane structure of this embodiment may further contain water as component (C). When component (A) with a high acid value is used, the combined use of components (B) and (C) can provide a composition for forming a lipid membrane structure in which component (A) has better solubility or dispersibility. Use of this composition for forming a lipid membrane structure tends to enable the formation of lipid membrane structures with excellent dispersibility in the aqueous phase. Furthermore, component (C) also serves to facilitate the incorporation of component (D) (a basic compound) and component (E) (an acidic compound) into the composition for forming a lipid membrane structure. Specifically, component (D) and / or component (E) can be easily incorporated into the composition for forming a lipid membrane structure by dissolving component (D) and / or component (E) in component (C) beforehand and then mixing with component (A) and component (B).

[0032] Component (C) is preferably water with few impurities, such as purified water, which is purified from tap water using a system that employs ion exchange, distillation, reverse osmosis, or ultrafiltration, either alone or in combination.

[0033] The content of component (C) in the composition for forming a lipid membrane structure of this embodiment is not particularly limited, but the lower limit is preferably 0.5% by mass or more, more preferably 1, 2, 3, 4, or 5% by mass or more, even more preferably 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15% by mass or more, and particularly preferably 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25% by mass or more. The upper limit is preferably 75% by mass or less, more preferably 70, 65, or 60% by mass or less, even more preferably 55, 50, 45, or 40% by mass or less, and particularly preferably 35 or 30% by mass or less.

[0034] Furthermore, in the composition for forming lipid membrane structures of this embodiment, the mass ratio (B) / (C) of the component (B) to the component (C) is preferably 0.3 to 100. The lower limit of this mass ratio range may be 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1.0. The upper limit of this mass ratio range may be 100, 90, 80, 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, or 6. The mass ratio range is, for example, more preferably 0.5 to 9, and even more preferably 1.0 to 6.

[0035] [Component (D)] The composition for forming a lipid membrane structure of this embodiment may further contain a basic compound as component (D). When component (A) with a high acid value is used, by adding component (D), a composition for forming a lipid membrane structure with better solubility or dispersibility of component (A) can be obtained, and use of this composition for forming a lipid membrane structure tends to improve the dispersibility of the lipid membrane structure in the aqueous phase. The component (D) may be one type or two or more types.

[0036] Examples of component (D) include inorganic bases such as sodium hydroxide, potassium hydroxide, and ammonia; basic amino acids such as arginine, lysine, and histidine; and amine compounds such as ethanolamine, diethanolamine, triethanolamine, 2-amino-2-methyl-1,3-propanediol (AMPD), and 2-amino-2-hydroxymethyl-1,3-propanediol (tromethamine). Of these, arginine is preferred.

[0037] The component (D) may be either a synthetic product or a commercially available product.

[0038] The content of component (D) in the composition for forming a lipid membrane structure of this embodiment is not particularly limited, but the lower limit is preferably 0.01% by mass or more, more preferably 0.02% by mass or more, and the upper limit is preferably 2% by mass or less, more preferably 1% by mass or less.

[0039] In the composition for forming a lipid membrane structure of this embodiment, the content of the component (D) is preferably at least 0.05 parts by mass, more preferably at least 0.1 parts by mass, as a lower limit, relative to 100 parts by mass of the component (A), and is preferably at most 10 parts by mass, more preferably at most 5 parts by mass.

[0040] [Component (E)] The composition for forming a lipid membrane structure of this embodiment may contain an acidic compound as component (E). By containing component (E), a composition for forming a lipid membrane structure having superior solubility or dispersibility of component (A) can be obtained, and use of this composition for forming a lipid membrane structure tends to improve the dispersibility of the lipid membrane structure in the aqueous phase. The component (E) may be one type or two or more types.

[0041] Examples of component (E) include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, and carbonic acid, and organic acids such as acetic acid, formic acid, propionic acid, butyric acid, citric acid, lactic acid, succinic acid, malic acid, tartaric acid, pyrrolidonecarboxylic acid (PCA), gluconic acid, benzoic acid, ethylenediaminetetraacetic acid (EDTA), etidronic acid, pentetic acid, and phytic acid. Among these, organic acids are preferred from the viewpoint of being able to obtain a composition for forming lipid membrane structures that is superior in solubility or dispersibility of component (A).

[0042] In particular, from the viewpoint of obtaining a composition for forming lipid membrane structures in which the component (A) has excellent solubility or dispersibility, from the viewpoint of forming lipid membrane structures with excellent dispersibility in an aqueous phase using the composition for forming lipid membrane structures, and from the viewpoint of improving the storage stability of the composition for forming lipid membrane structures and lipid membrane structure-containing compositions using the composition for forming lipid membrane structures, the component (E) is preferably an organic acid with chelating activity. The component (A) may have the property of easily binding to metal ions. In this case, adding an organic acid with chelating activity as the component (E) captures metal ions in the composition for forming lipid membrane structures, improving the storage stability of the composition for forming lipid membrane structures and making the component (A) more soluble or dispersible, thereby obtaining a composition for forming lipid membrane structures in which the component (A) has excellent solubility or dispersibility. It is presumed that the use of this composition will enable the formation of lipid membrane structures with excellent dispersibility in an aqueous phase and storage stability. As the organic acid having a chelating action, for example, citric acid, ethylenediaminetetraacetic acid (EDTA), etidronic acid, and pentetic acid are preferred, and ethylenediaminetetraacetic acid (EDTA) is more preferred.

[0043] The component (E) may be either a synthetic product or a commercially available product.

[0044] In the composition for forming a lipid membrane structure of this embodiment, the content of component (E) (in terms of free acid) is not particularly limited, but the lower limit is preferably 0.02% by mass or more, more preferably 0.04% by mass or more, and the upper limit is preferably 4% by mass or less, more preferably 2% by mass or less.

[0045] In the composition for forming a lipid membrane structure of this embodiment, the content of the component (E) (in terms of free acid) per 100 parts by mass of the component (A) is preferably 0.1 parts by mass or more, more preferably 0.2 parts by mass or more, as a lower limit, and more preferably 20 parts by mass or less, more preferably 10 parts by mass or less, as an upper limit.

[0046] From the viewpoint of increasing the solubility of the components (D) and (E) in the composition for forming lipid membrane structures and controlling the pH of the composition when dispersed in an aqueous phase within a predetermined range, the composition for forming lipid membrane structures of this embodiment preferably contains both the components (D) and (E). Such a composition for forming lipid membrane structures may be obtained by adding the components (D) and (E) separately, or by adding salts of the components (D) and (E).

[0047] The salts of component (D) and component (E) are not particularly limited, but examples include lysine hydrochloride; sodium citrate salts such as trisodium citrate; sodium phosphate salts such as disodium hydrogen phosphate; sodium benzoate; sodium ethylenediaminetetraacetate salts such as trisodium ethylenediaminetetraacetate (EDTA-3Na); and sodium diethylenetriaminepentaacetate salts such as pentasodium diethylenetriaminepentaacetate (pentasodium pentetate).

[0048] When the composition for forming a lipid membrane structure contains the component (D) and the component (E), the mass ratio (D) / (E) of the component (D) to the component (E) is 0.2 to 10. The lower limit of this mass ratio range may be 0.3, 0.4, or 0.5. The upper limit of this mass ratio range may be 10, 9, 8, 7, 6, or 5. The mass ratio range is preferably 0.5 to 5, for example.

[0049] In the composition for forming a lipid membrane structure of this embodiment, the total content of the components (D) and (E) is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, as a lower limit, and is preferably 4% by mass or less, more preferably 2% by mass or less, as an upper limit.

[0050] [Component (F)] The composition for forming a lipid membrane structure of this embodiment may further contain a fat-soluble compound as component (F). When component (A) with a high acid value is used, a composition for forming a lipid membrane structure with superior solubility or dispersibility of component (A) can be obtained by using component (B) and component (F) in combination. Use of this composition for forming a lipid membrane structure tends to enable the formation of lipid membrane structures with excellent dispersibility in the aqueous phase and high storage stability. Furthermore, use of component (F) in combination with component (D) and / or component (E) tends to enable the formation of finer lipid membrane structures. The component (F) may be one type or two or more types.

[0051] Examples of component (F) include sterols such as phytosterols, cholesterol, di(phytosteryl / octyldodecyl) lauroyl glutamate, phytosteryl oleate, and phytosteryl glucoside; triterpenes such as γ-oryzanol, glycyrrhizic acid, ursolic acid, and Centella asiatica extract (a mixture of asiatic acid, madecassic acid, and asiaticoside); fat-soluble vitamins such as retinol, hydrogenated retinol, cholecalciferol, tocopherol, and ascorbic acid esters; and astaxanthin. coenzymes such as ubiquinone; hydrocarbons such as limonene, petrolatum, and squalane; ceramides such as ceramide EOS, ceramide NG (ceramide 2), ceramide NP (ceramide 3), ceramide AP (ceramide 6II), ceramide EOP (ceramide 1), dihydroxylignoceroylphytosphingosine, cerebroside, glycosphingolipids, and cetyl PG hydroxyethyl palmitamide; and polyphenols such as tetrahydrodiferuloylmethane and pterostilbene. Among these, from the viewpoint that combining the component (F) with the components (A) and (B) mutually enhances the solubilities of the components (A) and (F), resulting in a composition for forming lipid membrane structures with excellent solubility of the component (A), ease of blending the component (F), and good storage stability, and from the viewpoint of improving the storage stability of a lipid membrane structure-containing composition using the composition for forming lipid membrane structures, it is preferable that the component (F) is at least one selected from the group consisting of phytosterols, cholesterol, γ-oryzanol, glycyrrhizinic acid, ursolic acid, Centella asiatica extract (a mixture of asiatic acid, madecassic acid, and asiaticoside), hydrogenated retinol, tocopherol, astaxanthin, ubiquinone, ceramide NG, ceramide NP, ceramide AP, ceramide EOP, tetrahydrodiferuloylmethane, and pterostilbene.

[0052] Component (F) may be either a synthetic product or a commercially available product. Examples of commercially available products include Phytosterol-SKP manufactured by Tama Biochemical Co., Ltd., TECA manufactured by Bayer, dl-α-tocopherol manufactured by DSM Ltd., NIKKOL (registered trademark) Retinol H10, NIKKOL (registered trademark) VC-IP, and squalane manufactured by Nikko Chemicals Co., Ltd., astaxanthin-20C and γ-oryzanol manufactured by Oryza Oil & Fat Chemical Co., Ltd., Kaneka Coenzyme Q10 manufactured by Kaneka Corporation, CERAMIDE 2 manufactured by Croda Japan Co., Ltd., and ursolic acid 90%, Sabi White, and Ptero White manufactured by Sabinsa Japan Corporation.

[0053] The content of component (F) in the composition for forming a lipid membrane structure of the present invention is not particularly limited, but the lower limit is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, even more preferably 0.1% by mass or more, and particularly preferably 1% by mass or more, and the upper limit is preferably 12% by mass or less, more preferably 10% by mass or less, even more preferably 8% by mass or less, and particularly preferably 6% by mass or less.

[0054] Furthermore, in the composition for forming a lipid membrane structure of this embodiment, the content of the component (F) is, relative to 100 parts by mass of the component (A), preferably 0.005 parts by mass or more, more preferably 0.05 parts by mass or more, even more preferably 0.5 parts by mass or more, and particularly preferably 5 parts by mass or more, as a lower limit, and preferably 60 parts by mass or less, more preferably 50 parts by mass or less, even more preferably 40 parts by mass or less, and particularly preferably 30 parts by mass or less, as an upper limit.

[0055] [Other Components] The lipid membrane structure-forming composition of this embodiment may further contain components (other components) other than the above components (A) to (F). Examples of other components include, but are not limited to, oils, surfactants, moisturizers, whitening agents, colorants, alcohols, amino acids, sugars, vitamins, viscosity modifiers, polymers, colorants, powders, UV absorbers, preservatives, antibacterial agents, antioxidants, fragrances, cosmetic ingredients, electrolytes, fibers, and plant extracts. These may be used alone or in combination of two or more. For example, by blending a cosmetic ingredient such as a moisturizer or whitening agent into the lipid membrane structure-forming composition and dispersing the lipid membrane structure-forming composition in an aqueous phase, lipid membrane structures encapsulating the cosmetic ingredient can be formed. When forming lipid membrane structures encapsulating the cosmetic ingredient, the timing of blending the cosmetic ingredient is not particularly limited. For example, a lipid membrane structure-forming composition containing ingredients other than the cosmetic ingredient may be prepared and then stored, and when preparing a lipid membrane structure-containing composition, the cosmetic ingredient may be added to the lipid membrane structure-forming composition, dissolved uniformly, and then dispersed in an aqueous phase to form lipid membrane structures encapsulating the cosmetic ingredient. Thus, the lipid membrane structure-forming composition not only simplifies the production of individual scalp and hair improving agents, but also allows different product groups to be easily produced by stocking the lipid membrane structure-forming composition in advance and changing the encapsulated cosmetic ingredient as desired.

[0056] From the viewpoint of obtaining finer lipid membrane structures, the pH of the composition for forming lipid membrane structures when dispersed in the aqueous phase is preferably 4.0 or higher, more preferably 5.0 or higher, even more preferably 7.0 or higher, and even more preferably 8.0 or higher. On the other hand, from the viewpoint of obtaining lipid membrane structures with uniform particle size (i.e., a highly uniform lipid membrane structure-containing composition), the pH of the composition for forming lipid membrane structures when dispersed in the aqueous phase is preferably 10.0 or lower, more preferably 9.5 or lower, and even more preferably 9.0 or lower. That is, the composition for forming lipid membrane structures of this embodiment preferably has a pH of 4.0 to 10.0 when dispersed in the aqueous phase. Here, the "pH of the composition for forming lipid membrane structures when dispersed in the aqueous phase" refers to the pH of the product obtained by dispersing the composition for forming lipid membrane structures in the aqueous phase, and is measured by the following method. 100 mL of purified water is added to a 200 mL beaker to prepare the aqueous phase. The aqueous phase is heated to 80°C, and the above-prepared composition for forming lipid membrane structures at 80°C is added while stirring at 100 rpm. After the addition is complete, the mixture is stirred at 80°C for 2 minutes to prepare a lipid membrane structure-containing composition. The above-prepared lipid membrane structure-containing composition is allowed to cool naturally to room temperature (25°C), and the pH at 25°C is measured using a pH meter (HM-25R, manufactured by DKK-TOA Corporation) using the glass electrode method.

[0057] <Lipid Membrane Structure-Containing Composition> The lipid membrane structure-containing composition of this embodiment is a composition containing lipid membrane structures formed from phospholipids with an acid value of 5 mgKOH / g or more, and can be obtained using the lipid membrane structure-forming composition described above. However, as long as the composition contains lipid membrane structures formed from phospholipids with an acid value of 5 mgKOH / g or more, it will exhibit the effect of the scalp hair improving agent of this embodiment, and therefore the production method is not particularly limited, and known methods can be used. For example, fine monolayer lamellar structures may be prepared using the sonication method, the ethanol injection method, or the cholic acid removal method. In addition, in methods for preparing lipid membrane structures containing multilayer lamellar structures, such as the Bangham method or the polyhydric alcohol method, fine lipid membrane structures may be prepared by combining a high-pressure emulsifier such as a microfluidizer or a micronization method such as the extrusion method. When forming lipid membrane structures using such known methods, the composition for forming lipid membrane structures described above is not limited to its composition, except that the lipid membrane structure contains a phospholipid with an acid value of 5 mgKOH / g or more as a component constituting the lipid membrane structure. The composition may be prepared using components and steps suitable for each production method.

[0058] The form of the lipid membrane structure is not particularly limited as long as it has a lamellar (lipid bilayer) structure in which lipid molecules are arranged with their hydrophilic groups facing outward and their hydrophobic groups facing inward, and examples thereof include liposomes, bicelles, and α-gels. The lipid membrane structure may be a single-layer lamellar structure called a unilamellar or single-lamellar structure, a multi-layered (2 to 10 layers) lamellar structure called an oligolamellar structure, a multi-lamellar structure with more layers, or a mixture of these. The lipid membrane structure is preferably a single-layer lamellar structure. A single-layer lamellar structure has a fine particle size and excellent compound encapsulation efficiency and permeability. The fact that the lipid membrane structure is a single-layer lamellar structure can be confirmed, for example, using cryo-electron microscopy (cryo-TEM). In this embodiment, the lipid membrane structure is preferably a single-layer lamellar liposome. A single-layer lamellar liposome has a fine particle size and a large internal aqueous phase volume, resulting in excellent water-soluble compound encapsulation efficiency and permeability. Therefore, it is useful in scalp and hair improvement agents that contain a water-soluble cosmetic ingredient. Furthermore, in this embodiment, the lipid membrane structures are preferably bicelles. Bicelles are fine, disc-shaped, unilamellar structures with a thickness of 3 to 10 nm and a diameter of 15 to 100 nm, and are excellent in encapsulation efficiency and penetration of fat-soluble ingredients. Therefore, it is useful in scalp and hair improvement agents that contain a fat-soluble cosmetic ingredient. The lipid membrane structure-containing composition of this embodiment may contain only one type of unilamellar liposome or bicelles, or these two types may be present together.

[0059] The upper limit of the average hydrodynamic diameter of the lipid membrane structures is preferably 200 nm or less, more preferably 190, 180, 170, 160, 150, 140, 130, 120, 110, 100, 90, or 80 nm or less, from the viewpoints of dispersibility, storage stability, and permeability into scalp hair. The lower limit of the average hydrodynamic diameter of the lipid membrane structures is not particularly limited, but is, for example, 20 nm or more, from the viewpoint of the efficiency of forming unilamellar structures.

[0060] From the viewpoints of dispersibility, storage stability, and permeability into scalp and hair, the upper limit of the polydispersity index (PDI) of the lipid membrane structures is preferably 0.80 or less, more preferably 0.50 or less, even more preferably 0.40 or less, still more preferably 0.30 or less, still more preferably 0.25 or less, and particularly preferably 0.20 or less. The lower limit of the polydispersity index (PDI) of the lipid membrane structures is not particularly limited, but is, for example, 0.01 or more.

[0061] The average hydrodynamic diameter and polydispersity index (PDI) of the lipid membrane structures are measured using a dynamic light scattering measurement device (Zetasizer Nano ZSP, manufactured by Malvern Instruments) and the harmonic mean diameter (Z-Average) and polydispersity index (PDI) based on scattered light intensity by cumulant analysis are used. The definitions of the average hydrodynamic diameter and polydispersity index used here are as described in "JIS Z8828:2019 Particle size analysis - dynamic light scattering method."

[0062] From the viewpoint of obtaining a sufficient scalp hair improving effect, the concentration of the lipid membrane structures in the lipid membrane structure-containing composition is preferably 0.0001% by mass or more, more preferably 0.01% by mass or more, and even more preferably 1% by mass or more. On the other hand, the upper limit of the concentration is not particularly limited, but is, for example, less than 5% by mass.

[0063] The pH of the lipid membrane structure-containing composition is preferably 4.0 to 10.0, specifically, the pH measured using a pH meter (HM-25R, manufactured by DKK-TOA Corporation) by the glass electrode method.

[0064] <Method for Producing a Lipid Membrane Structure-Containing Composition> The method for producing a lipid membrane structure-containing composition of the present invention is not particularly limited. When forming lipid membrane structures using a known method, the composition may be produced using components and steps appropriate for each production method, except that a phospholipid with an acid value of 5 mg KOH / g or more is included as a component constituting the lipid membrane structure. Furthermore, when using the composition for forming lipid membrane structures described above, a method in which a large excess of water is added to a composition for forming lipid membrane structures obtained by mixing the above-mentioned component (A) with, optionally, components (B) to (F) and other components, or a method in which the composition for forming lipid membrane structures is added to, a large excess of water, may be used. From the viewpoint of improving the dispersibility of the lipid membrane structures, the latter method is preferred. That is, in the method for producing a lipid membrane structure-containing composition according to this embodiment, it is preferable to disperse the composition for forming lipid membrane structures obtained by mixing the above-mentioned component (A) with, optionally, components (B) to (F) and other components, in an aqueous phase.

[0065] More specifically, the method for producing a lipid membrane structure-containing composition in this embodiment preferably comprises a step of mixing the above-mentioned component (A) with, as needed, one or more components selected from the group consisting of component (B), component (C), component (D), component (E), component (F), and other components to obtain a composition for forming lipid membrane structures (mixing step), and a step of dispersing the composition for forming lipid membrane structures in an aqueous phase (dispersing step).

[0066] (Mixing Step) In the mixing step, the components may be mixed all at once or sequentially. When the components are mixed sequentially, the order is not particularly limited. For example, when preparing a composition for forming a lipid membrane structure using the components (A), (B), and (C), the components (A) and (B) may be mixed, and then the component (C) may be added and mixed; the components (A) and (C) may be mixed, and then the component (B) may be added and mixed; or the components (B) and (C) may be added simultaneously to the component (A) and then mixed (e.g., by adding a mixed solvent of the components (B) and (C)). Furthermore, for example, when preparing a composition for forming a lipid membrane structure using the components (A) and (B) as well as the components (C), (D), and / or (E), the components (C), (D), and / or (E) may be added separately, or they may be mixed in advance and then the mixture added. Furthermore, for example, when preparing a composition for forming a lipid membrane structure using the above-mentioned components (A), (B), and (F) as well as the components (C), (D), and / or (E), the order of addition of component (F) is not particularly limited. For example, after mixing components (A), (B), and (F), components (C), (D), and / or (E) may be added simultaneously or sequentially. Alternatively, components (A) and (B) may be mixed simultaneously or sequentially with component (C), (D), and / or (E) added last. Furthermore, when preparing a composition for forming a lipid membrane structure using the components described above in [Other Components], the order of addition of the components described above in [Other Components] is not particularly limited and can be selected appropriately depending on, for example, solubility. For example, if the component is lipid-soluble, it may be added together with the component (F) or last. Alternatively, if it is water-soluble, it may be added together with the addition of component (C), component (D) and / or component (E), or may be added last.

[0067] The mixing temperature when mixing the components is not particularly limited, but is preferably equal to or higher than the phase transition temperature of component (A). For example, the upper limit is 120, 110, 100, 95, or 90°C, and the lower limit is 40, 45, 50, 55, 60, 65, 70, 75, 80, or 85°C. For example, it is 40 to 120°C, preferably 40 to 100°C, and more preferably 60 to 90°C. The mixing time is also not particularly limited, but is preferably 10 to 180 minutes. The mixing method is not particularly limited, but since it does not require high mechanical shearing force, it can be performed using known mixing means such as a magnetic stirrer (e.g., a hot stirrer), a paddle mixer, a propeller mixer, or a planetary mixer.

[0068] In the mixing step, in addition to the step of mixing the above-mentioned components, other steps such as purification (for example, filtration), cooling, storage, etc. may be appropriately performed. For example, a mixture is prepared by mixing component (A) and component (B) with, optionally, components (C) to (F) and a portion of other components, and undissolved matter contained in the mixture is removed by filtration. The mixture is then cooled and stored, and when preparing a lipid membrane structure-containing composition, the remaining components (B) to (F) and other components are blended into the mixture as necessary to obtain a composition for forming lipid membrane structures.

[0069] (Dispersion Step) The dispersion of the composition for forming lipid membrane structures obtained in the mixing step into the aqueous phase may be carried out without stirring the aqueous phase (the composition for forming lipid membrane structures may be added to the aqueous phase), or may be carried out while stirring the aqueous phase, or the aqueous phase may be added to the composition for forming lipid membrane structures. The stirring conditions for the aqueous phase and / or the composition for forming lipid membrane structures are not particularly limited, but may be carried out, for example, at a rotation speed of 10 to 300 rpm using a known stirring means. The composition for forming lipid membrane structures and / or the aqueous phase may be added all at once, in portions, or sequentially at any desired rate using a known dropwise addition means.

[0070] The aqueous phase preferably uses water with few impurities, such as purified water purified from tap water by a system that uses ion exchange, distillation, reverse osmosis, or ultrafiltration, either alone or in combination. Furthermore, the aqueous phase may further contain components other than water, as long as the lipid membrane structure can be formed. Examples of components other than water include oils, surfactants, moisturizers, whitening agents, coloring materials, alcohols, amino acids, sugars, vitamins, viscosity modifiers, polymers, colorants, powders, UV absorbers, preservatives, antibacterial agents, antioxidants, fragrances, cosmetic ingredients, electrolytes, fibers, and plant extracts.

[0071] In the dispersion step, the temperature of the aqueous phase is preferably equal to or higher than the phase transition temperature of component (A), since this tends to result in efficient formation of lipid membrane structures. The upper limit of the aqueous phase temperature is, for example, 100, 95, or 90°C, and the lower limit is 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, or 60°C. The temperature of the aqueous phase is, for example, 0 to 100°C, preferably 25 to 100°C, more preferably 40 to 95°C, and even more preferably 60 to 90°C.

[0072] In the dispersing step, the temperature of the composition for forming lipid membrane structures to be dispersed is preferably equal to or higher than the phase transition temperature of component (A), since this tends to result in efficient formation of lipid membrane structures. The upper limit of the temperature of the composition for forming lipid membrane structures is, for example, 120, 110, 100, 95, or 90°C, and the lower limit is 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, or 60°C. The temperature of the composition for forming lipid membrane structures is, for example, 0 to 120°C, preferably 25 to 120°C, more preferably 40 to 100°C, and even more preferably 60 to 90°C.

[0073] In the method for producing a lipid membrane structure-containing composition of this embodiment, in addition to the above-mentioned mixing and dispersing steps, other steps such as purification (for example, filtration), cooling, and storage may be further carried out.

[0074] <Scalp Hair Improvement Agent> The lipid membrane structure-containing composition of the present embodiment may be used as a scalp hair improvement agent as it is, or the lipid membrane structure-containing composition may be blended into cosmetics or topical scalp hair preparations to impart a scalp hair improvement effect.

[0075] The form of the scalp hair improvement agent of this embodiment is not particularly limited as long as the lipid membrane structures can be stably incorporated, and examples thereof include lotion, gel, emulsion, cream, shampoo, spray, etc. From the viewpoint of taking advantage of the transparent appearance, penetrating feel upon application, and high stability that are achieved by containing the fine lipid membrane structures of this embodiment (for example, having an average hydrodynamic diameter of 200 nm or less), it is preferable to incorporate the agent into a low-viscosity lotion, in which it is difficult to incorporate lipid membrane structures.

[0076] In addition to the lipid membrane structure-containing composition, the scalp and hair improving agent of this embodiment may further contain ingredients that are commonly used in cosmetics or topical scalp and hair preparations, provided that the effects of the present invention are not impaired. Examples of such ingredients include, but are not limited to, oils, surfactants, moisturizers, whitening agents, coloring materials, alcohols, amino acids, vitamins, viscosity adjusters, polymers, colorants, powders, UV absorbers, preservatives, antibacterial agents, antioxidants, fragrances, cosmetic ingredients, electrolytes, pH adjusters, fibers, water, and plant extracts.

[0077] The concentration of the lipid membrane structures in the scalp and hair improving agent containing the lipid membrane structure-containing composition of this embodiment is preferably 0.0001% by mass or more, more preferably 0.01% by mass or more, and even more preferably 1% by mass or more. On the other hand, the upper limit of the concentration is not particularly limited, but is, for example, less than 5% by mass.

[0078] The scalp and hair improving effect is not particularly limited as long as it improves scalp and hair problems, and examples include one or more of the following: hair firmness improving effect, hair strength improving effect, hair gloss improving effect, hair moisture improving effect, hair frizz improving effect, split end prevention effect, color fade suppression effect, bedhead prevention effect, bedhead elimination effect, hair surface repair effect, scalp moisture improving effect, scalp dandruff prevention effect, scalp itching improving effect, scalp inflammation suppression effect, scalp odor suppression effect, hair growth effect, hair care effect, and gray hair reduction effect.

[0079] The scalp hair improvement effect includes either an immediate effect or a continuous effect, or both. An immediate effect refers to, for example, an effect that begins to appear 1 to 30 minutes, preferably 3 to 20 minutes, and more preferably 5 to 15 minutes after application of the scalp hair improvement agent to the scalp hair. A continuous effect refers to, for example, an effect that begins to appear 1 day to 1 month, preferably 3 days to 3 weeks, and more preferably 5 days to 2 weeks after continuous application of the scalp hair improvement agent to the scalp hair twice a day, morning and night, and the effect is maintained or further enhanced as long as the application is continued thereafter.

[0080] The present invention will be explained in more detail using examples and comparative examples, but the present invention is not limited to these examples. In the following examples, unless otherwise specified, various operations were carried out at room temperature (20 to 25°C). Furthermore, unless otherwise specified, "%" and "parts" mean "% by mass" and "parts by mass", respectively.

[0081] <Preparation of lipid membrane structure-containing composition> A lipid membrane structure-containing composition was prepared by the following method. Lecithin was prepared by purchasing commercially available soybean-derived hydrogenated and non-hydrogenated lecithins with different acid values ​​(acid value 0.3 to 30.8 mg KOH / g) and mixing them in a ratio to obtain the desired acid value. The following six types of soybean-derived hydrogenated and non-hydrogenated lecithins were used: Hydrogenated lecithin, acid value 0.3 mg KOH / g Hydrogenated lecithin, acid value 6.1 mg KOH / g Hydrogenated lecithin, acid value 15.0 mg KOH / g Hydrogenated lecithin, acid value 20.0 mg KOH / g Hydrogenated lecithin, acid value 23.1 mg KOH / g Non-hydrogenated lecithin, acid value 17.0 mg KOH / g

[0082] [Examples 1 to 7, Comparative Examples 1 and 2] Components (A) to (F) shown in Table 1 (contents in parts by mass) were heated to 80°C and mixed uniformly to obtain a composition for forming lipid membrane structures. The composition for forming lipid membrane structures described above was added to component (G) heated to 80°C, mixed uniformly, and then cooled to obtain a lipid membrane structure-containing composition. In Comparative Example 2, unmixed oil droplets were present when components (A) to (F) were mixed, and a homogeneous solution was not obtained. Furthermore, the composition obtained by mixing this with an aqueous phase had a cloudy appearance, and the formation of lipid membrane structures could not be confirmed.

[0083] [Appearance] The appearance of the lipid membrane structure-containing compositions prepared in the Examples and Comparative Examples was visually observed at 25°C in a glass bottle container with a diameter of 3.7 cm, and the appearance was evaluated based on the following criteria (a rating of ⊚ or ◯ indicates that the dispersibility of the lipid membrane structures is good): ⊚: A transparent or semi-transparent liquid in which the letters on the opposite side of the container are visible. ◯: A homogeneous liquid in which the letters on the opposite side of the container are not visible. ×: Separation or precipitation is observed.

[0084] [Presence or Absence of Lipid Membrane Structure Formation] The lipid membrane structure-containing compositions prepared in the Examples and Comparative Examples were subjected to cryo-TEM observation using a transmission electron microscope (H-7650, manufactured by Hitachi High-Technologies Corporation), and the presence or absence of lipid membrane structure formation was evaluated based on the following criteria (if ◎ or ○, it can be determined that lipid membrane structures have been formed): ◎: Unilamellar liposome structures and bicelle structures are observed. ○: In addition to unilamellar liposome structures and bicelle structures, multilamellar liposome structures are observed. ×: No lipid membrane structures are observed.

[0085] [Mean Hydrodynamic Diameter, Polydispersity Index (PDI)] The mean hydrodynamic diameter and polydispersity index (PDI) of the lipid membrane structures in the lipid membrane structure-containing composition prepared above were measured by cumulant analysis using a dynamic light scattering measurement device (Zetasizer Nano ZSP, manufactured by Malvern Instruments).

[0086] Figure 1 shows a cryo-TEM image of the lipid membrane structure-containing composition obtained in Example 5. The ring-shaped images indicate unilamellar liposome structures, and the rod-shaped images indicate bicelle structures, confirming the formation of lipid membrane structures with a unilamellar structure.

[0087] [Scalp Hair Improvement Effect Test] Using the lipid membrane structure-containing compositions obtained in the Examples and Comparative Examples as samples, the following effect tests a to z were conducted by a panel of 20 expert members (men and women in their 20s to 50s), and the effects compared to before application were evaluated by sensory evaluation based on the following criteria. ◎: Very effective ○: Effective △: No change ×: Worsening condition a [Immediate hair firmness improvement effect] Each sample was applied to hair, and the immediate hair firmness improvement effect after blow-drying was evaluated. b [Continuous hair firmness improvement effect] Each sample was applied to hair twice a day, morning and evening, and the ongoing hair firmness improvement effect after one week was evaluated. c [Immediate hair stiffness improvement effect] Each sample was applied to hair, and the immediate hair stiffness improvement effect after blow-drying was evaluated. d [Continuous hair stiffness improvement effect] Each sample was applied to hair twice a day, morning and evening, and the ongoing hair stiffness improvement effect after one week was evaluated. e [Effect of improving immediate hair gloss] Each sample was applied to hair, and the effect of improving immediate hair gloss after drying was evaluated. f [Effect of improving continuous hair gloss] Each sample was applied to hair twice a week, morning and evening, and the effect of improving continuous hair gloss after one week was evaluated. g [Effect of improving immediate hair gloss] Each sample was applied to hair, and the effect of improving immediate hair gloss after drying was evaluated. h [Effect of improving continuous hair gloss] Each sample was applied to hair twice a week, morning and evening, and the effect of improving continuous hair gloss after one week was evaluated. i [Effect of improving immediate hair moisture] Each sample was applied to hair, and the effect of improving immediate hair moisture after drying was evaluated. j [Effect of improving continuous hair moisture] Each sample was applied to hair twice a week, morning and evening, and the effect of improving continuous hair moisture after one week was evaluated. k [Immediate hair frizz improvement effect] Each sample was applied to hair, and the immediate hair frizz improvement effect after drying was evaluated. l [Continuous hair frizz improvement effect] Each sample was applied to hair twice a day, morning and evening, and the continuous hair frizz improvement effect after one week was evaluated. m [Split-end prevention effect] Each sample was applied to hair twice a day, morning and evening, and the split-end prevention effect was evaluated four weeks after the start of application.n [Effect of preventing color fading] Each sample was applied to hair twice a day, morning and night, and the effect of preventing color fading was evaluated for four weeks after the start of application. o [Effect of preventing bedhead] Each sample was applied to hair and the effect of preventing bedhead the following morning was evaluated. p [Effect of eliminating bedhead] Each sample was applied to hair and the effect of eliminating bedhead after using a hair dryer was evaluated. q [Effect of repairing hair surface (cuticle)] Each sample was applied to hair and the effect of repairing hair surface (cuticle) after using a hair dryer was evaluated. r [Effect of improving immediate scalp moisture] Each sample was applied to the scalp and the effect of improving immediate scalp moisture was evaluated. s [Effect of improving continuous scalp moisture] Each sample was applied to the scalp twice a day, morning and night, and the effect of improving continuous scalp moisture after one week was evaluated. t [Scalp dandruff prevention effect] Each sample was applied to the scalp twice a week, morning and night, and the scalp dandruff prevention effect was evaluated after one week. u [Scalp itching improvement effect] Each sample was applied to the scalp twice a week, morning and night, and the scalp itching improvement effect was evaluated after one week. v [Scalp inflammation suppression effect] Each sample was applied to the scalp twice a week, morning and night, and the scalp inflammation suppression effect was evaluated after one week. w [Scalp odor improvement effect] Each sample was applied to the scalp twice a week, morning and night, and the scalp odor improvement effect was evaluated after one week. x [Hair growth effect] Each sample was applied to the scalp twice a week, morning and night, and the hair growth effect was evaluated over a period of six months from the start of application. y [Hair growth effect] Each sample was applied to the scalp twice a week, morning and night, and the hair growth effect was evaluated over a period of six months from the start of application. z [Effect of preventing gray hair] Each sample was applied to the scalp twice a day, morning and evening, and the effect of preventing gray hair was evaluated for six months after the start of application.

[0088] The results of each of the above evaluations are shown in Table 1 below.

[0089] As shown in Table 1, the compositions of Examples 1 to 7, in which lipid membrane structures formed from hydrogenated and non-hydrogenated lecithin with an acid value of 5 mgKOH / g or more were dispersed, exhibited scalp and hair improving effects such as improving hair wrinkles and firmness, improving scalp moisture retention, and preventing scalp dandruff. On the other hand, Comparative Example 1 used hydrogenated lecithin with an acid value of less than 5 mgKOH / g, and although the formation of lipid membrane structures was confirmed, the scalp and hair improving effect was insufficient. Comparative Example 2 used hydrogenated lecithin with an acid value of 5 mgKOH / g or more, but the incorporation of excessive squalane resulted in the formation of an O / W emulsion rather than a lipid membrane structure, and the scalp and hair improving effect was insufficient.

Claims

1. A scalp and hair improving agent comprising a composition containing a lipid membrane structure formed from phospholipids having an acid value of 5 mg KOH / g or more.

2. The scalp and hair improving agent according to claim 1, wherein the phospholipid is a hydrogenated phospholipid.

3. A scalp and hair improvement agent according to claim 1 or 2, wherein the lipid membrane structure is a single-layer lamellar structure.

4. A scalp and hair improvement agent according to claim 1 or 2, wherein the average hydrodynamic diameter of the lipid membrane structures is 200 nm or less.

5. A scalp and hair improvement agent according to claim 1 or 2, which has the effect of improving hair firmness.

6. A scalp and hair improving agent according to claim 1 or 2, which has the effect of improving hair strength.

7. A scalp and hair improving agent according to claim 1 or 2, which has the effect of improving hair gloss.

8. A scalp and hair improvement agent according to claim 1 or 2, which has the effect of improving hair gloss.

9. A scalp and hair improvement agent according to claim 1 or 2, which has the effect of improving hair moisture retention.

10. A scalp and hair improvement agent according to claim 1 or 2, which has the effect of reducing hair frizz.

11. A scalp and hair improving agent according to claim 1 or 2, which has the effect of preventing split ends.

12. A scalp and hair improvement agent according to claim 1 or 2, which has the effect of inhibiting color fading.

13. A scalp and hair improving agent according to claim 1 or 2, which has the effect of preventing bedhead.

14. A scalp and hair improving agent according to claim 1 or 2, which has the effect of eliminating bedhead.

15. A scalp and hair improvement agent according to claim 1 or 2, which has a hair surface repair effect.

16. A scalp and hair improvement agent according to claim 1 or 2, which has the effect of improving scalp moisturizing.

17. A scalp and hair improvement agent according to claim 1 or 2, which has the effect of preventing dandruff on the scalp.

18. A scalp and hair improvement agent according to claim 1 or 2, which has the effect of alleviating scalp itching.

19. A scalp and hair improvement agent according to claim 1 or 2, which has an effect of suppressing scalp inflammation.

20. A scalp and hair improvement agent described in claim 1 or 2, which has the effect of suppressing scalp odor.

21. A scalp and hair improvement agent according to claim 1 or 2, which has a hair growth effect.

22. A scalp and hair improving agent according to claim 1 or 2, which has a hair growth effect.

23. A scalp and hair improvement agent according to claim 1 or 2, which has the effect of improving gray hair.

Images