Phospholipid-containing composition, cosmetic, and topical skin preparation

Abstract

Provided is a phospholipid-containing composition having improved stability over time, the composition being characterized by containing a phospholipid (A), as an essential component, in which polyvalent cations have been substantially reduced, and further containing one or more of a polyol compound (B), and water (C). Further provided is a cosmetic and a topical skin preparation characterized by being obtained by blending the phospholipid-containing composition therewith.

Description

Phospholipid-containing composition, cosmetic, and external preparation for skin

[0001] The present invention relates to a phospholipid-containing composition with improved stability over time, and cosmetics and external preparations for skin containing the composition.

[0002] Phospholipids are a major component of biological membranes and are used in various cosmetics and external preparations for skin because of their high safety for the skin.

[0003] In addition, phospholipids have a hydrophilic part and a hydrophobic part and form lipid membrane structures such as vesicles (liposomes) and bicelles having a lipid bilayer (lamella) structure. Therefore, they have a good moisturizing effect and are well tolerated by the skin, and are expected to be incorporated into more cosmetics and external preparations for skin in the future.

[0004] As a prior art document of an external preparation for skin containing phospholipids, for example, Patent Document 1 discloses a skin improver containing a composition containing a lipid membrane structure formed by a phospholipid having an acid value of 5 mg KOH / g or more.

[0005] Japanese Unexamined Patent Application Publication No. 2024-078511

[0006] On the other hand, due to structures such as the hydrophilic part / hydrophobic part and double bonds, phospholipids are likely to undergo various changes and have been a problem in lacking stability over time.

[0007] In particular, all compositions containing phospholipids are likely to undergo various changes such as coloring, odor, precipitation, aggregation, and sedimentation during long-term storage, and such changes often affect cosmetics and external preparations for skin containing phospholipids.

[0008] Therefore, there is a need for a technology to maintain the long-term stability of compositions containing phospholipids and cosmetics and external preparations for skin formulated with the composition.

[0009] Therefore, the present invention has been made in view of the above problems, and an object thereof is to provide a phospholipid-containing composition containing phospholipids with improved stability over time compared to the conventional ones, and cosmetics and external preparations for skin formulated with the composition.

[0010] As a result of intensive studies to solve the above problems, the present inventors have found that a phospholipid-containing composition containing, as an essential component, a phospholipid substantially reduced in polyvalent cations, and further containing one or more of a polyol compound and water, has improved stability over time compared to the prior art. A cosmetic and a topical skin preparation containing the composition can also be obtained.

[0011] (1) One aspect of the present invention is a phospholipid-containing composition having improved stability over time, which contains: (A) a phospholipid substantially reduced in polyvalent cations, as an essential component, and further contains one or more of (B) a polyol compound and (C) water. (2) In the aspect of (1) above, (D) a polyvalent cation complexing agent may further be contained. (3) In the aspect of (1) or (2) above, the component (A) may be a phospholipid in which polyvalent cations are substantially reduced to 2500 ppm or less. (4) In the aspect of (1) or (2) above, the component (A) may be a hydrogenated phospholipid. (5) In the aspect of (1) or (2) above, the component (B) may be at least one selected from the group consisting of 1,2-pentanediol, 1,2-hexanediol, 1,2-heptanediol, cyclohexyl glycerin, and hexyl glycerin. (6) A cosmetic characterized by containing the phospholipid-containing composition of (1) or (2) above may be provided. (7) A topical skin preparation characterized by containing the phospholipid-containing composition of (1) or (2) above may be provided.

[0012] According to the present invention, it is possible to provide a phospholipid-containing composition containing a phospholipid having improved stability over time compared to the prior art, and a cosmetic and a topical skin preparation containing the composition.

[0013] Hereinafter, embodiments of the present invention will be described in detail.

[0014] <Phospholipid-containing composition> The phospholipid-containing composition with improved temporal stability according to an embodiment of the present invention is characterized by containing (A) a phospholipid with substantially reduced polyvalent cations as an essential component, and further containing one or more of (B) a polyol compound and (C) water. Each of these substances will be described below.

[0015] [(A) Phospholipids with substantially reduced polyvalent cations] (A) Phospholipids with substantially reduced polyvalent cations are phospholipids in which the amount of polyvalent cations contained is reduced compared to phospholipids that are normally commercially available or produced by known manufacturing methods. By substantially reducing the amount of polyvalent cations contained in phospholipids, changes such as oxidation reactions, hydrolysis reactions, and polymerization reactions caused by polyvalent cations, as well as the discoloration, odor, precipitation, aggregation, and sedimentation of phospholipids caused by these changes, can be suppressed, and as a result the long-term stability of the phospholipid itself is also improved.

[0016] In this context, "substantial" means not only phospholipids whose polyvalent cation content has been reduced by the polyvalent cation reduction treatment described later, but also phospholipids in which, along with phospholipids with the normal amount of polyvalent cations, the polyvalent cations have formed complexes and been stabilized by adding the (D) polyvalent cation complexing agent described later, thereby reducing the amount of free polyvalent cations that affect the stability of the phospholipid.

[0017] While there are no particular restrictions on the origin of the phospholipid, lecithin is particularly preferred because it is naturally derived and suitable for use in cosmetics and topical skin preparations. Lecithin may be derived from soybeans, egg yolks, rapeseed, sunflowers, corn, etc., and is preferably of plant origin such as soybeans, rapeseed, sunflowers, or corn. Soybean-derived lecithin is even more preferred due to its availability and quality stability.

[0018] Also, as the phospholipid, from the viewpoint of preventing oxidative deterioration during the heating process in the production of cosmetics and external skin preparations and oxidative deterioration during the storage of those products, it is preferably a hydrogenated (hydrogenated) phospholipid. The hydrogenated phospholipid can be obtained by adding hydrogen atoms to the unsaturated carbon bonds of the phospholipid by a conventionally known method. Furthermore, as the hydrogenated phospholipid, hydrogenated lecithin is preferable, and hydrogenated lecithin derived from soybeans is particularly preferable.

[0019] Specifically, the polyvalent cations substantially reduced in the component (A) include aluminum (Al ３＋ ), americium (Am ３＋ ), barium (Ba ２＋ ), beryllium (Be ２＋ ), bismuth (Bi ３＋ ), berkelium (Bk ３＋ ), calcium (Ca ２＋ ), cadmium (Cd ２＋ ), cerium (Ce ３＋ , Ce ４＋ ), californium (Cf ３＋ ), curium (Cm ３＋ ), cobalt (Co ２＋ , Co ３＋ ), chromium (Cr ２＋ , Cr ３＋ ), copper (Cu ２＋ ), dysprosium (Dy ３＋ ), erbium (Er ３＋ ), europium (Eu ３＋ ), iron (Fe ２＋ , Fe ３＋ ), fermium (Fm ３＋ ), gallium (Ga ３＋ ), gadolinium (Gd ３＋ ), hafnium (Hf ４＋ ), mercury (Hg ２＋ ), holmium (Ho ３＋ ), indium (In ３＋ ), lanthanum (La ３＋ ), lutetium (Lu ３＋ ), magnesium (Mg ２＋ ), manganese (Mn ２＋ , Mn ３＋ ), molybdenum (Mo５＋ Mo ６＋ ), niobium (Nb ５＋ ), neodymium (Nd ３＋ ), nickel (Ni ２＋ ), Neptunium (NpO ２ ２＋ ), protactinium (Pa ５＋ ), lead (Pb ２＋ ), palladium (Pd ２＋ ), promethium (Pm ３＋ ), Praseogym (Pr ３＋ ), plutonium (Pu ３＋ , Pu ４＋ , Pu ６＋ ), antimony (Sb ３＋ ), scandium (Sc ３＋ ), samarium (Sm ３＋ ), tin (Sn ２＋ ), strontium (Sr ２＋ ), terbium (Tb ３＋ ), Thorium (Th ４＋ ), Titanium (Ti ３＋ , TiO ２＋ , Ti(H ２ O ２ )), Thallium (Tl ３＋ ), Thulium (Tm ３＋ ), uranium (U ４＋ , UO ２ ２＋ ), vanadium (V ２＋ , VO ２＋ , V ５＋ ), Yttrium (Y ３＋ ), ytterbium (Yb ３＋ ), zinc (Zn ２＋ ) and zirconium (Zr ４＋ ) contains each of the polyvalent cations shown in parentheses.

[0020] For treatment to reduce polyvalent cations contained in phospholipids, any material with ion exchange or ion adsorption capacity can be used. Examples include activated carbon, alumina, silica gel, Fluorisyl, activated clay, diatomaceous earth, adsorbents, ion exchange resins, zeolites, bentonite, montmorillonite, stivunsite, hectorite, savonite, molecular sieves, aluminosilicates, chelate resins, chelate fibers, hydroxyapatite, clay minerals, phosphonates, polyphosphonates, coprecipitants, Celite, and insoluble matrices. Among these, treatment with ion exchange resins and chelate resins is preferred. As the ion exchange resin used in the treatment, cation exchange resins are preferred, and among these, strongly acidic cation exchange resins having sulfonic acid groups are preferred.

[0021] The processing conditions using ion exchange resin can be appropriately set depending on the type of ion exchange resin used and the amount of polyvalent cations contained in the phospholipid before processing. There is no particular order in which the processing to reduce polyvalent cations is performed. For example, the reduction treatment may be performed in advance under one or more solvents different from (B) and (C), then the used solvent may be removed to temporarily extract the phospholipid, and this may be used in the phospholipid-containing composition as polyvalent cation-reduced phospholipid. Alternatively, the reduction treatment may be performed under a solvent other than (B) and (C), and without temporarily extracting the phospholipid as a standalone product, the solvent may be subsequently replaced with one containing (B) and / or (C). Furthermore, the reduction treatment may be incorporated from the beginning under a solvent containing (B) and / or (C). In this case, (B), (C), and other solvents may be used in combination to suit the reduction treatment, or unnecessary solvents may be removed after the reduction treatment, or the ratio of (B) and (C) may be adjusted to suit the intended use.

[0022] In component (A), phospholipids with substantially reduced polyvalent cations are preferably phospholipids in which the polyvalent cations are substantially reduced to 2500 ppm or less, 2400 ppm or less, 2300 ppm or less, 2200 ppm or less, 2100 ppm or less, 2000 ppm or less, 1900 ppm or less, 1800 ppm or less, 1700 ppm or less, 1600 ppm or less, and 1500 ppm or less, and particularly 1400 ppm or less, 1300 ppm or less, and 1200 ppm or less. It is more preferable that the amount be 1100 ppm or less, 1000 ppm or less, 900 ppm or less, 800 ppm or less, 700 ppm or less, 600 ppm or less, and 500 ppm or less; it is even more preferable that it be 400 ppm or less, 300 ppm or less, 200 ppm or less, and 100 ppm or less; and it is particularly preferable that it be 90 ppm or less, 80 ppm or less, 70 ppm or less, 60 ppm or less, 50 ppm or less, 40 ppm or less, 30 ppm or less, 20 ppm or less, and 10 ppm or less. The time-dependent stability of the phospholipid is further improved when the amount of polyvalent cations is 2500 ppm or less.

[0023] (A) As for the amount of phospholipids with substantially reduced polyvalent cations, from the viewpoint of stability, the lower limit is preferably 5% by mass or more, 6% by mass or more, 7% by mass or more, 8% by mass or more, and 9% by mass or more, relative to the total amount of the composition, more preferably 10% by mass or more, 11% by mass or more, 12% by mass or more, 13% by mass or more, and 14% by mass or more, and even more preferably 15% by mass or more, 16% by mass or more, 17% by mass or more, 18% by mass or more, and 19% by mass or more. Further, the upper limit is preferably 50 mass% or less, 49 mass% or less, 48 ​​mass% or less, 47 mass% or less, 46 mass% or less, 45 mass% or less, 44 mass% or less, 43 mass% or less, 42 mass% or less, 41 mass% or less, 40 mass% or less, 39 mass% or less, 38 mass% or less, 37 mass% or less, 36 mass% or less, 35 mass% or less, It is more preferably 34 mass% or less, 33 mass% or less, 32 mass% or less, 31 mass% or less, 30 mass% or less, 29 mass% or less, 28 mass% or less, 27 mass% or less, 26 mass% or less, 25 mass% or less, 24 mass% or less, 23 mass% or less, 22 mass% or less, 21 mass% or less, 20 mass% or less.

[0024] [(B) Polyol Compound] Furthermore, the phospholipid-containing composition according to the embodiment of the present invention includes a dispersion medium for dispersing the phospholipid, which is component (A), having a substantially reduced polyvalent cation. The dispersion medium includes one or more of (B) a polyol compound and (C) water, but a mixture of (B) a polyol compound and (C) water is preferred.

[0025] (B) The polyol compound may be, for example, a compound represented by the following formula (1).

[0026] In formula (1) above, 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.

[0027] C2-C6 alkyl groups may be linear or branched. Examples of C2-C6 alkyl groups include ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, iso-amyl group, tert-pentyl group, neopentyl group, n-hexyl group, 3-methylpentan-2-yl group, 3-methylpentan-3-yl group, 4-methylpentyl group, 4-methylpentan-2-yl group, 1,3-dimethylbutyl group, 3,3-dimethylbutyl group, 3,3-dimethylbutan-2-yl group, etc. C2-C6 alkyl groups are preferably linear. That is, C2-C6 alkyl groups are preferably groups selected from the group consisting of ethyl group, n-propyl group, n-butyl group, n-pentyl group, and n-hexyl group.

[0028] Examples of cycloalkyl groups having 3 to 6 carbon atoms include cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl groups, with cyclohexyl being preferred.

[0029] The substituents that may be present in C2-C6 alkyl groups and C3-C6 cycloalkyl groups are not particularly limited as long as they achieve the effects of the present invention. Examples of substituents include halogen atoms, acyl groups, alkyl groups, aryl groups, alkoxyl groups, nitro groups, amino groups, and cyano groups. However, C2-C6 alkyl groups are not substituted with alkyl groups. In formula (1) above, X is -O-, -C(=O)O-, or -O-C(=O)-, and is preferably -O-. Also, in formula (1) above, n is 0 or 1. In formula (1) above, when X is -O- and n is 1, the number of carbon atoms in the alkyl group as R is preferably 4 or more.

[0030] Among the compounds represented by formula (1), it is preferable that at least one is selected from the group consisting of 1,2-pentanediol, 1,2-hexanediol, 1,2-heptanediol, cyclohexylglycerin, and hexylglycerin, from the viewpoint of dispersibility and the long-term stability of phospholipids. Note that (B) polyol compounds may be used in combination of one or more types as appropriate.

[0031] (B) Regarding the amount of polyol compound, from the viewpoint of dispersibility and the long-term stability of phospholipids, the lower limit is preferably 15% by mass or more, 16% by mass or more, 17% by mass or more, 18% by mass or more, 19% by mass or more, 20% by mass or more, 21% by mass or more, 22% by mass or more, 23% by mass or more, 24% by mass or more, 25% by mass or more, 26% by mass or more, 27% by mass or more, 28% by mass or more, 29% by mass or more, and 30% by mass or more. It is more preferable that the amount is % or more, 31% or more by mass, 32% or more by mass, 33% or more by mass, 34% or more by mass, and 35% or more by mass, and it is even more preferable that the amount is 36% or more by mass, 37% or more by mass, 38% or more by mass, 39% or more by mass, 40% or more by mass, 41% or more by mass, 42% or more by mass, 43% or more by mass, 44% or more by mass, 45% or more by mass, 46% or more by mass, 47% or more by mass, 48% or more by mass, 49% or more by mass, and 50% or more by mass. The upper limits are 95% by mass or less, 94% by mass or less, 93% by mass or less, 92% by mass or less, 91% by mass or less, 90% by mass or less, 89% by mass or less, 88% by mass or less, 87% by mass or less, 86% by mass or less, 85% by mass or less. Below, preferably 84% by mass or less, 83% by mass or less, 82% by mass or less, 81% by mass or less, 80% by mass or less, 79% by mass or less, 78% by mass or less, 77% by mass or less, 76% by mass or less, 75% by mass or less, More preferably 74% by mass or less, 73% by mass or less, 72% by mass or less, 71% by mass or less, 70% by mass or less, 69% by mass or less, 68% by mass or less, 67% by mass or less, 66% by mass or less, 65% by mass or less, More preferably, the content is 64% by mass or less, 63% by mass or less, 62% by mass or less, 61% by mass or less, 60% by mass or less, 59% by mass or less, 58% by mass or less, 57% by mass or less, 56% by mass or less, and 55% by mass or less.

[0032] [(C) Water] Regarding the amount of (C) water, from the viewpoint of dispersibility and the long-term stability of phospholipids, the lower limit is preferably 0.5% by mass or more, 1% by mass or more, 2% by mass or more, 3% by mass or more, 4% by mass or more, 5% by mass or more, 6% by mass or more, 7% by mass or more, 8% by mass or more, 9% by mass or more, and 10% by mass or more relative to the total amount of composition. It is more preferably 11% by mass or more, 12% by mass or more, 13% by mass or more, 14% by mass or more, 15% by mass or more, 16% by mass or more, 17% by mass or more, 18% by mass or more, 19% by mass or more, and 20% by mass or more. It is even more preferably 21% by mass or more, 22% by mass or more, 23% by mass or more, 24% by mass or more, and 25% by mass or more. In addition, the upper limits are 75 mass% or less, 74 mass% or less, 73 mass% or less, 72 mass% or less, 71 mass% or less, 70 mass% or less, 69 mass% or less, 68 mass% or less, 67 mass% or less, 66 mass% or less, 65 mass% or less, 64 mass% or less, It is preferably 63 mass% or less, 62 mass% or less, 61 mass% or less, 60 mass% or less, 59 mass% or less, 58 mass% or less, 57 mass% or less, 56 mass% or less, 55 mass% or less, 54 mass% or less, 53 mass% or less, 52 mass% or less % or less, 51 mass% or less, 50 mass% or less, 49 mass% or less, 48 ​​mass% or less, 47 mass% or less, 46 mass% or less, 45 mass% or less, 44 mass% or less, 43 mass% or less, 42 mass% or less, 41 mass% or less Below, 40% by mass or less, 39% by mass or less, 38% by mass or less, 37% by mass or less, 36% by mass or less, 35% by mass or less, 34% by mass or less, 33% by mass or less, 32% by mass or less, 31% by mass or less, and 30% by mass or less.

[0033] Furthermore, when mixing (B) polyol compounds and (C) water, the amount of the mixture should be determined from the viewpoint of dispersibility and the long-term stability of phospholipids, with a minimum of 15% by mass, 16% by mass, 17% by mass, 18% by mass, 19% by mass, 20% by mass, 21% by mass, 22% by mass, 23% by mass, 24% by mass, 25% by mass, 26% by mass, 27% by mass, 28% by mass, 29% by mass, and 30% by mass, relative to the total amount of the composition. It is preferable that the amount be % or more, more preferably 31% by mass or more, 32% by mass or more, 33% by mass or more, 34% by mass or more, 35% by mass or more, 36% by mass or more, 37% by mass or more, 38% by mass or more, 39% by mass or more, and 40% by mass or more, and even more preferably 41% by mass or more, 42% by mass or more, 43% by mass or more, 44% by mass or more, 45% by mass or more, 46% by mass or more, 47% by mass or more, 48% by mass or more, 49% by mass or more, and 50% by mass or more. The upper limits are 95% by mass or less, 94% by mass or less, 93% by mass or less, 92% by mass or less, 91% by mass or less, 90% by mass or less, 89% by mass or less, 88% by mass or less, 87% by mass or less, 86% by mass or less, 85% by mass or less. Below, preferably 84% by mass or less, 83% by mass or less, 82% by mass or less, 81% by mass or less, 80% by mass or less, 79% by mass or less, 78% by mass or less, 77% by mass or less, 76% by mass or less, 75% by mass or less, More preferably 74% by mass or less, 73% by mass or less, 72% by mass or less, 71% by mass or less, 70% by mass or less, 69% by mass or less, 68% by mass or less, 67% by mass or less, 66% by mass or less, 65% by mass or less, More preferably, the content is 64% by mass or less, 63% by mass or less, 62% by mass or less, 61% by mass or less, 60% by mass or less, 59% by mass or less, 58% by mass or less, 57% by mass or less, 56% by mass or less, and 55% by mass or less.

[0034] [(D) Polyvalent Cation Complexing Agents] (D) Polyvalent cation complexing agents are not particularly limited as long as they can complex polyvalent cations, but examples include inorganic bases such as sodium hydroxide, potassium hydroxide, and ammonia; basic amino acids such as arginine, lysine, and histidine; basic compounds such as amine compounds such as ethanolamine, diethanolamine, triethanolamine, 2-amino-2-methyl-1,3-propanediol (AMPD), and 2-amino-2-hydroxymethyl-1,3-propanediol (tromethamine); inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, and carbonic acid; acidic compounds such as organic acids such as acetic acid, formic acid, propionic acid, butyric acid, citric acid, lactic acid, succinic acid, malic acid, tartaric acid, pyrrolidone carboxylic acid (PCA), gluconic acid, benzoic acid, ethylenediaminetetraacetic acid (EDTA), etidronic acid, pentetic acid, and phytic acid, and salts thereof. In particular, from the viewpoint of forming a more stable complex, organic acids and their salts that have chelating properties are preferred. Preferred examples of such substances include citrates such as trisodium citrate, edetates such as disodium ethylenediaminetetraacetate and trisodium ethylenediaminetetraacetate, tetrasodium etidronate, tetrasodium ethylenediaminesuccinate, sodium gluconate, tetrasodium glutamate diacetate, sodium phytate, sodium hexametaphosphate, pentasodium pentetate, and sodium metaphosphate.

[0035] Among the above, (D) as a polyvalent cation complexing agent, citrate salts such as trisodium citrate or EDTA salts such as trisodium ethylenediaminetetraacetate are preferred from the viewpoint of the stability of the chelate complex formed.

[0036] (D) The amount of polyvalent cation complexing agent is preferably, from the viewpoint of the long-term stability of the phospholipid, at a lower limit of 0.01% by mass or more, 0.02% by mass or more, 0.03% by mass or more, and 0.04% by mass or more, more preferably 0.05% by mass or more, 0.06% by mass or more, and 0.07% by mass or more, and even more preferably 0.08% by mass or more, 0.09% by mass or more, and 0.1% by mass or more, relative to the total amount of the composition. Furthermore, the upper limit is preferably 4.5% by mass or less and 4.0% by mass or less, more preferably 3.5% by mass or less and 3.0% by mass or less, and even more preferably 2.5% by mass or less and 2.0% by mass or less.

[0037] [(E) Other Components] The phospholipid-containing composition of the present invention may contain other components, as long as the stability of the phospholipids over time is maintained. Examples of such components include polyol compounds other than component (B), oils, surfactants, humectants, whitening agents, colorants, alcohols, amino acids, sugars, vitamins, viscosity modifiers, polymers, colorants, powders, UV absorbers, preservatives, antibacterial agents, antioxidants, fragrances, beauty ingredients, electrolytes, fibers, plant extracts, etc. The order of addition of these other components is not particularly limited and they can be appropriately selected, for example, according to their solubility.

[0038] <Lipid Membrane Structure-Containing Composition> The phospholipid-containing composition of the present invention may need to be dispersed in the aqueous phase depending on the usage conditions. One form of the phospholipid-containing composition is a lipid membrane structure-containing composition. The lipid membrane structure and the composition containing it will be described below.

[0039] The morphology 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 include liposomes, bicelles, and α-gels. The lipid membrane structure may be a single-layer lamellar structure called a unilamella or single lamellar, a multi-layer (2 to 10 layers) lamellar structure called an oligolamella, or a multi-lamellar structure with more layers, and these may be mixed. 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. In one embodiment of the present invention, the lipid membrane structure is preferably a single-layer lamellar liposome. A single-layer lamellar liposome has a fine particle size and a high internal aqueous phase volume, and therefore has excellent compound encapsulation efficiency and permeability. For this reason, it is useful in cosmetics and topical skin preparations that contain water-soluble beauty ingredients. In another embodiment of the present invention, the lipid membrane structure is preferably a bicell. Bycell is a fine, disc-shaped, single-layer lamellar structure with a thickness of 3 to 10 nm and a diameter of 15 to 100 nm, and exhibits excellent encapsulation and penetration of lipid-soluble components. Therefore, it is useful in cosmetics and topical skin preparations that contain lipid-soluble cosmetic ingredients. In the lipid membrane structure-containing composition according to the present invention, only one of single-layer lamellar liposomes and Bycell may be present, or these two may be mixed together.

[0040] The lipid membrane structure-containing composition of the present invention is obtained by dispersing a phospholipid-containing composition in an aqueous phase. The phospholipid-containing composition can be easily dispersed in the aqueous phase by heating. The temperature range can be 60°C to 95°C, preferably 65°C to 90°C, and more preferably 70°C to 90°C.

[0041] The lipid membrane structure-containing composition of the present invention contains phospholipids with substantially reduced polyvalent cations in water as an essential component, and optionally contains a polyol compound and a polyvalent cation complexing agent. The timing of adding the polyvalent cation complexing agent to the lipid membrane structure-containing composition is not particularly limited, and it is possible to add the polyvalent cation complexing agent to the aqueous phase when dispersing the phospholipid-containing composition in the aqueous phase, to add the polyvalent cation complexing agent after dispersion in the aqueous phase, or to add the polyvalent cation complexing agent to the phospholipid-containing composition before dispersion in the aqueous phase. Among these, it is preferable to add the polyvalent cation complexing agent to the phospholipid-containing composition before dispersion in the aqueous phase.

[0042] <Cosmetics or Topical Skin Preparations> The phospholipid-containing composition according to the present invention can contain phospholipids with improved temporal stability compared to conventional compositions. It can be diluted in advance in a solvent containing (B) and / or (C), allowing for long-term storage while maintaining good handling properties. As a result, the addition of additives to ensure the stability of phospholipids becomes unnecessary, which not only reduces manufacturing costs but also minimizes allergies and skin irritation caused by additives, resulting in skin-friendly cosmetics and topical skin preparations.

[0043] The phospholipid-containing composition of the present invention can be used as a cosmetic or topical skin preparation on its own, or it can be incorporated into cosmetics or topical skin preparations to impart skincare effects such as moisturizing. Therefore, one embodiment of the present invention is a cosmetic preparation containing the above-mentioned phospholipid-containing composition. Another embodiment of the present invention is a topical skin preparation containing the above-mentioned phospholipid-containing composition. The phospholipid-containing composition may also be incorporated in the form of the lipid membrane structure-containing composition described above.

[0044] The form of the cosmetic and topical skin preparation of the present invention is not particularly limited as long as the phospholipids are stably incorporated, but examples include lotion, gel, emulsion, cream, shampoo, and facial cleanser. From the viewpoint of taking advantage of the transparency of appearance, penetration upon application, and high stability obtained by containing the phospholipids and lipid membrane structures formed by the phospholipids of the present invention, it is preferable to incorporate them into low-viscosity lotions where it is difficult to incorporate lipid membrane structures.

[0045] In addition to the phospholipid-containing composition described above, the cosmetics and topical skin preparations of the present invention may further contain ingredients commonly used in cosmetics and topical skin preparations, to the extent that they do not impair the effects of the present invention. Examples of such ingredients include, but are not limited to, polyol compounds other than component (B), oils, surfactants, moisturizers, whitening agents, colorants, alcohols, amino acids, vitamins, viscosity modifiers, polymers, colorants, powders, UV absorbers, preservatives, antibacterial agents, antioxidants, fragrances, beauty ingredients, electrolytes, pH adjusters, fibers, water, plant extracts, etc.

[0046] The concentration of phospholipids in cosmetics and topical skin preparations containing the phospholipid-containing composition of the present invention is preferably, as a lower limit, 0.01% by mass or more, 0.02% by mass or more, 0.05% by mass or more, and 0.1% by mass or more, more preferably 0.2% by mass or more, 0.3% by mass or more, 0.4% by mass or more, 0.5% by mass or more, 0.6% by mass or more, 0.7% by mass or more, 0.8% by mass or more, 0.9% by mass or more, and 1.0% by mass or more, and even more preferably 1.1% by mass or more, 1.2% by mass or more, 1.3% by mass or more, 1.4% by mass or more, 1.5% by mass or more, 1.6% by mass or more, 1.7% by mass or more, 1.8% by mass or more, 1.9% by mass or more, and 2.0% by mass or more. On the other hand, there is no particular upper limit to the concentration, but for example, it is less than 15% by mass, less than 14% by mass, less than 13% by mass, less than 12% by mass, less than 11% by mass, less than 10% by mass, less than 9.5% by mass, less than 9.0% by mass, less than 8.5% by mass, less than 8.0% by mass, less than 7.5% by mass, less than 7.0% by mass, less than 6.5% by mass, less than 6.0% by mass, less than 5.5% by mass, and less than 5.0% by mass.

[0047] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Furthermore, the amounts of ingredients in the following examples are expressed in mass percent unless otherwise specified.

[0048] <Examples 1-11, Comparative Examples 1-3> In a 100 mL beaker, component A or component A', and components B, C, and D as needed, were added in the amounts listed in Table 1. The mixture was stirred at 80°C for 20 minutes using a hot stirrer to prepare the phospholipid-containing compositions of Examples 1-11 and Comparative Examples 1-3. Furthermore, the prepared phospholipid-containing compositions were dispersed in the aqueous phase at 80°C to obtain lipid membrane structure-containing compositions.

[0049] <Example 12, Comparative Example 4> In addition to the lipid membrane structure-containing compositions of Examples 1 to 11 and Comparative Examples 1 to 3 described above, water was heated to 80°C in the amounts shown in Table 2, and the phospholipid compositions of Example 10 or Comparative Example 1, which were also heated and dissolved at 80°C, were dispersed in the water to obtain the lipid membrane structure-containing compositions of Example 12 and Comparative Example 4, respectively.

[0050] <Comparative Example 5> In addition, water and trisodium citrate dihydrate were uniformly heated and dissolved at 80°C in the amounts shown in Table 2, and the phospholipid composition of Comparative Example 1, which was also heated and dissolved at 80°C, was dispersed to obtain the lipid membrane structure-containing composition of Comparative Example 5.

[0051] <Comparative Example 6> Furthermore, using the amounts shown in Table 2, water was heated to 80°C, and the phospholipid composition of Comparative Example 1, which had also been heated and dissolved at 80°C, was dispersed. Then, an aqueous solution of trisodium citrate dihydrate heated to 80°C was added to obtain the lipid membrane structure-containing composition of Comparative Example 6.

[0052] Furthermore, the content of various elements in the prepared phospholipid-containing composition was measured using an ICP emission spectrometer (ICP-OES), and the amount of polyvalent cations in the phospholipids was calculated.

[0053] In the ICP emission spectrometer, the general-purpose mixed standard solution XSTC-22 (manufactured by Nishishin Shoji Co., Ltd.) was used for the measurement. The above general-purpose mixed standard solution contains aluminum (Al), boron (B), barium (Ba), calcium (Ca), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), potassium (K), lithium (Li), magnesium (Mg), manganese (Mn), molybdenum (Mo), sodium (Na), nickel (Ni), phosphorus (P), lead (Pb), antimony (Sb), silicon (Si), titanium (Ti), vanadium (V), and Although it contains 23 elements including zinc (Zn), the polyvalent cations targeted for measurement in this study were limited to 17 elements (polyvalent cations): aluminum (Al), barium (Ba), calcium (Ca), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), antimony (Sb), titanium (Ti), vanadium (V), and zinc (Zn).

[0054] Furthermore, in Examples 10 to 12, a polyvalent cation complexing agent was formulated together with hydrogenated lecithin. Assuming that all molecules of the polyvalent cation complexing agent chelated the polyvalent cations, the amount of chelated polyvalent cations, calculated from the number of moles of the polyvalent cation complexing agent, was subtracted from the amount of polyvalent cations measured by the phospholipid alone before formulation to determine the effective amount of polyvalent cations.

[0055] <Evaluation of the Composition> [Appearance (Tendency to Colorize Phospholipid-Containing Composition)] The above-prepared phospholipid-containing composition was stored in a 3.7 cm diameter glass bottle at 5°C and 40°C for one month, and its appearance (tendency to colorize) was judged according to the following criteria (◎ or ○ indicates good stability over time). ◎: No tendency to colorize when stored at 40°C compared to when stored at 5°C ○: Almost no tendency to colorize when stored at 40°C compared to when stored at 5°C △: Slight tendency to colorize when stored at 40°C compared to when stored at 5°C ×: Clear tendency to colorize when stored at 40°C compared to when stored at 5°C

[0056] [Appearance (Coloring tendency of lipid membrane structure-containing composition)] The lipid membrane structure-containing composition prepared above was stored in a 3.7 cm diameter glass bottle at 5°C and 40°C for one month, and its appearance (coloring tendency) was judged according to the following criteria (◎ or ○ indicates good stability over time). ◎: No difference in coloring tendency ○: Almost no difference in coloring tendency △: Slight coloring tendency when stored at 40°C ×: Clear coloring tendency when stored at 40°C

[0057] [Appearance (Tendency to suppress precipitation of lipid membrane structure-containing composition)] The lipid membrane structure-containing composition prepared above was stored in a 3.7 cm diameter glass bottle at 5°C and 40°C for one month, and its appearance (tendency to suppress precipitation) was judged according to the following criteria (◎ or ○ indicates good stability over time). ◎: No difference in precipitation tendency ○: Almost no difference in precipitation tendency △: Slight tendency to precipitate when stored at 40°C ×: Clear tendency to precipitate when stored at 40°C

[0058] The evaluation results for Examples 1 to 11 and Comparative Examples 1 to 3, as well as the formulations of each example and comparative example, are shown in Table 1 below.

[0059] Furthermore, the evaluation results for Example 12 and Comparative Examples 4-6, as well as the formulations of each example and comparative example, are shown in Table 1 below.

[0060] As is clear from the results in Table 1, there was almost no difference in appearance after long-term storage of the phospholipid-containing compositions and lipid membrane structure-containing compositions in Examples 1 to 11, confirming that the phospholipids contained had improved stability over time compared to conventional compositions. On the other hand, the phospholipid-containing compositions and lipid membrane structure-containing compositions in Comparative Examples 1 to 3 showed a tendency towards discoloration or precipitation in the appearance evaluation according to one of the criteria.

[0061] Furthermore, as is clear from the results in Table 2, there was almost no difference in the appearance of the lipid membrane structure-containing composition in Example 12 after long-term storage, confirming that its stability over time was improved. On the other hand, the lipid membrane structure-containing composition in Comparative Example 4 showed a tendency to discolor and precipitate after long-term storage, and although the lipid membrane structure-containing compositions in Comparative Examples 5 and 6 had the same composition as Example 12, they showed a slight tendency to discolor after long-term storage.

[0062] Although preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the embodiments described above, and various modifications and changes are possible within the scope of the gist of the present invention as described in the claims.

[0063] The phospholipid-containing composition of the present invention suppresses changes such as oxidation, hydrolysis, and polymerization reactions, and can also suppress discoloration, odor, precipitation, aggregation, and sedimentation of phospholipids caused by these changes. As a result, a phospholipid-containing composition containing phospholipids with improved temporal stability compared to conventional compositions can be obtained. Furthermore, by incorporating such a phospholipid-containing composition containing phospholipids with improved temporal stability into cosmetics and topical skin preparations, changes such as discoloration, odor, precipitation, aggregation, and sedimentation can also be suppressed in such cosmetics and topical skin preparations. Moreover, such effects not only make it possible to provide cosmetics and topical skin preparations with longer shelf lives, but also allow for the incorporation of phospholipids into formulations where it was previously difficult to incorporate them from a stability standpoint. This greatly expands the scope of product development that takes advantage of the various benefits of phospholipids, such as safety, moisturizing effect, and pleasant feel.

Claims

1. A phospholipid-containing composition with improved temporal stability, characterized in that it contains (A) a phospholipid with substantially reduced polyvalent cations as an essential component, and further contains one or more of (B) a polyol compound and (C) water.

2. The phospholipid-containing composition according to claim 1, further characterized by comprising (D) a polyvalent cation complexing agent.

3. The phospholipid-containing composition according to claim 1 or 2, characterized in that component (A) is a phospholipid in which the polyvalent cation is substantially reduced to 2500 ppm or less.

4. The phospholipid-containing composition according to claim 1 or 2, characterized in that the component (A) is a hydrogenated phospholipid.

5. The phospholipid-containing composition according to claim 1 or 2, characterized in that the component (B) is at least one selected from the group consisting of 1,2-pentanediol, 1,2-hexanediol, 1,2-heptanediol, cyclohexylglycerin, and hexylglycerin.

6. A cosmetic composition characterized by comprising the phospholipid-containing composition described in claim 1 or 2.

7. A topical skin preparation characterized by comprising the phospholipid-containing composition described in claim 1 or 2.

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