Topical skin preparations

Abstract

To provide a topical skin preparation that has superior stability, exhibits superior spread during application, leaves no oily feeling, and ensures a superior user experience.SOLUTION: A topical skin preparation contains degummed and bleached oil derived from Nannochloropsis oceanica.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an external preparation for skin. [Background Art]

[0002] Conventionally, in cosmetics for skin protection and moisturization, animal and plant-derived triglycerides that are solid at room temperature such as beeswax, shea butter, and Japan wax derived from Rhus succedanea fruit, or glyceryl tri(caprylate / caprate / myristate / stearate) with a fatty acid composition adjusted according to the desired properties, have been used for purposes such as reducing stickiness during application. For example, Patent Document 1 describes that an oily solid cosmetic containing dextrin fatty acid ester, naturally-derived solid fat and / or semi-solid fat, and isoparaffin is excellent in use feeling, skin protectiveness, and stability over time. Patent Document 2 describes that a solid cosmetic composition containing shea butter, cocoa butter, at least one component selected from Abyssinian oil, meadowfoam oil and an antioxidant, and a vegetable liquid oil does not cause stickiness when applied to the skin and has high oxidative stability. Patent Document 3 describes that an emulsified cosmetic composition containing an oily component selected from hydrocarbon oils, fatty acid triglycerides and fatty acid monoesters, di(octyldodecyl / phytosteryl / behenyl) lauroyl glutamate, and water is excellent in firm feeling during application and lack of stickiness after application. [Prior Art Literature] [Patent Literature]

[0003] [Patent Document 1] Japanese Unexamined Patent Application Publication No. 2017-114780 [Patent Document 2] Japanese Unexamined Patent Application Publication No. 2020-63224 [Patent Document 3] Japanese Unexamined Patent Application Publication No. 2021-11459 [Summary of the Invention] [Problems that the invention aims to solve]

[0004] However, plant and animal-derived triglycerides that are solid at room temperature do not have high solubility in liquid oils, and even if they are melted at around 80°C, they may solidify and precipitate at room temperature. Therefore, formulations that utilize the properties of solid triglycerides at room temperature have been limited to solid cosmetics and formulations combined with certain amphiphilic substances. In particular, when incorporated at high concentrations in liquid oil formulations and emulsified formulations, there were issues with storage stability. Furthermore, when incorporating solid triglycerides at room temperature, it is necessary to maintain high temperatures inside the equipment during the manufacturing process to ensure uniform dissolution of the raw material, which requires a lot of energy.

[0005] Furthermore, while the demand for plant-derived, room-temperature solid triglycerides, such as those derived from palm oil, is increasing year by year, a significant increase in production is unlikely, raising concerns about future supply chains. In particular, there are negative opinions regarding the continued use of triglycerides, such as shea butter, which are recognized as edible oils, as cosmetic ingredients amidst a global food shortage. Therefore, alternative oils are desired. This invention relates to a topical skin preparation that is excellent in terms of stability, usability, and feel. [Means for solving the problem]

[0006] The inventors of the present invention have discovered that by using an oil prepared from a culture of a specific species of microalga, Nannochloropsis, and then degummed and decolorized, it is possible to obtain a topical skin preparation that does not precipitate with Nannochloropsis-derived oil, has excellent storage stability, spreads well when applied, does not feel oily, and has a good feel to use, thus completing the present invention.

[0007] The present invention relates to a topical skin preparation containing a degummed and decolorized oil derived from Nannochloropsis oceanica. [Effects of the Invention]

[0008] The topical skin preparation of the present invention does not cause precipitation of the nannochloropsis-derived oil, has excellent storage stability, spreads well when applied, does not feel oily or sticky, and has a good feel to use. [Modes for carrying out the invention]

[0009] The oil used in this invention can be obtained from a culture of Nannochloropsis oceanica, a microalga belonging to the genus Nannochloropsis. Nannochloropsis is a marine organism belonging to the division Heterokonta, group Euonymus algae, and is used in fish farming and other applications. Extracts of Nannochloropsis have been studied as active ingredients in cosmetics for their antioxidant stress-reducing and skin-tightening effects (Japanese Patent Publication No. 2006-232766, Japanese Patent Publication No. 2019-532966). However, there are no reported cases of Nannochloropsis extract being used as an oily base in cosmetics such as oil formulations or emulsifiers.

[0010] The Nannochloropsis oceanica used in this invention can be cultured in a culture medium prepared by adding chelating agents and buffers commonly used in algal cultivation, such as ammonium sulfate and calcium superphosphate, to seawater. Cultivation is preferably carried out by excessive light irradiation in a closed system using a photoreactor, from the viewpoint of preventing contamination by other microorganisms and concentrating antioxidant components.

[0011] Nannochloropsis oceanica can be used after cultivation, or after concentration of the algae by centrifugation, filtration, etc., as needed, or after further sterilization by heating. Furthermore, methods such as pressing, solvent extraction using hexane or ethyl acetate, and pressure extraction can be used to obtain the oil.

[0012] The oil derived from Nannochloropsis oceanica (hereinafter referred to as "Nannochloropsis-derived oil") is used after degumming and decolorization. Degumming can be performed using water, or aqueous solutions of phosphoric acid or citric acid, or enzyme solutions, as needed. Decolorization can be performed using adsorbents such as activated carbon. Furthermore, deodorization may be performed in combination by exposure to water vapor or heating.

[0013] The nannochloropsis-derived oil used in this invention is a solid that partially melts at 20°C, but it can melt at a lower temperature than other solid fats commonly used in cosmetics, such as beeswax. The temperature at which the majority of the nannochloropsis-derived oil used in this invention melts and exhibits fluidity is preferably 45°C or lower, and more preferably 20 to 40°C.

[0014] In the topical skin preparation of the present invention, the content of nannochloropsis-derived oil is preferably 0.01 to 35% by mass, and more preferably 0.1 to 25% by mass, in the total composition, from the viewpoint of improving storage stability, improving spreadability during application, and reducing stickiness such as an oily feeling, without the nannochloropsis-derived oil precipitation.

[0015] When the topical skin preparation of the present invention is a non-aqueous oil preparation, the content of the nannochloropsis-derived oil is preferably 0.1 to 35% by mass, more preferably 1 to 33% by mass, and even more preferably 8 to 25% by mass in the total composition.

[0016] The topical skin preparation of the present invention can be made into an emulsified preparation by using water and a surfactant together with a nannochloropsis-derived oil. When the topical skin preparation of the present invention is an emulsified preparation, the content of the nannochloropsis-derived oil is preferably 0.01 to 20% by mass of the total composition, more preferably 0.02 to 10% by mass, even more preferably 0.03 to 5% by mass, and still more preferably 0.04 to 1% by mass.

[0017] As the surfactant, ionic surfactants and nonionic surfactants can be used. Examples of nonionic surfactants include polyoxyethylene hydrogenated castor oil, polyoxyethylene alkyl ethers, polyoxyethylene fatty acid esters, polyoxyethylene alkanol ethers, polyglycerin fatty acid esters, sucrose fatty acid esters, polyoxyethylene sorbit beeswax, glycolipids, and the like. Among these, from the viewpoints of preventing precipitation of an oil agent derived from Nannochloropsis, improving storage stability, improving spreadability upon application, and reducing greasiness such as oily feeling, it is preferable that the surfactant comprises one or more selected from polyoxyethylene hydrogenated castor oil, polyoxyethylene alkyl ethers and polyoxyethylene fatty acid esters, it is more preferable that the surfactant comprises one or more selected from polyoxyethylene hydrogenated castor oil and polyoxyethylene alkyl ethers, and it is still more preferable that the surfactant comprises polyoxyethylene hydrogenated castor oil. Examples of ionic surfactants include hydrogenated soybean phospholipids, egg yolk lecithin, acyl glutamates, sodium surfactin, acyl sulfates, and the like.

[0018] When the external preparation for skin of the present invention is an oil-in-water emulsion preparation, it is preferable to use a nonionic surfactant. The HLB of the nonionic surfactant is preferably from 9 to 18, and from the viewpoint of allowing a user to feel a change in the texture of the cosmetic during application, HLB of 11 to 16 is more preferred, and HLB of 12 to 15 is even more preferred. Further, when the external preparation for skin of the present invention is a water-in-oil emulsion preparation, it is preferable to use a nonionic surfactant. The HLB of the nonionic surfactant is preferably from 1 to 9, more preferably from 2 to 8, and even more preferably from 3 to 7.

[0019] Here, HLB (Hydrophilic-Lipophilic Balance) indicates the molecular weight of the hydrophilic group portion relative to the total molecular weight of a surfactant, and is determined by Griffin's formula. When the surfactant is composed of two or more nonionic surfactants, the HLB of the mixed surfactant is determined as follows. The (mixed) HLB of the mixed surfactant is the arithmetic average of the HLB values of each nonionic surfactant calculated based on their blending ratios. Mixed HLB=Σ(HLBx×Wx) / ΣWx HLBx represents the HLB value of nonionic surfactant X. Wx represents the mass (g) of nonionic surfactant X having the HLB value of HLBx.

[0020] One or more surfactants may be used in combination. From the viewpoints of preventing precipitation of the oil agent derived from Nannochloropsis, improving storage stability, spreading property upon application, and reducing greasiness such as oily feeling, the content of the surfactant is preferably 0.05 to 6% by mass, more preferably 0.1 to 5% by mass, still more preferably 0.3 to 4% by mass, and even more preferably 0.5 to 3.5% by mass, relative to the total mass of the composition.

[0021] When the external preparation for skin of the present invention is formulated as an emulsion preparation, the water content is preferably 20 to 99% by mass, more preferably 35 to 98% by mass, relative to the total mass of the composition.

[0022] When the external preparation for skin of the present invention is formulated as an emulsion preparation, it can further contain a polyhydric alcohol, which can improve spreading property upon application and reduce greasiness such as oily feeling. A polyhydric alcohol is a compound having two or more hydroxyl groups in the molecule, and any polyhydric alcohol commonly used in conventional external preparations for skin may be used. Examples of dihydric alcohols include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, butylene glycol, and propanediol. Examples of trihydric alcohols include glycerin and trimethylolpropane. Examples of tetrahydric alcohols include diglycerin and erythritol. Examples of pentahydric or higher polyhydric alcohols include polyglycerins such as triglycerin; sugars and sugar alcohols such as glucose, maltose, maltodose, sucrose, xylitol, sorbitol, malbitol, polyoxyethylene methyl glucoside, polyoxyethylene ethyl glucoside, and polyoxyethylene propylene glucoside.

[0023] Polyhydric alcohols can be used individually or in combination of two or more types. From the viewpoint of improving spreadability during application and reducing stickiness such as oiliness, the content is preferably 0.5 to 50% by mass, more preferably 1 to 40% by mass, and even more preferably 2 to 30% by mass in the total composition.

[0024] The topical skin preparation of the present invention may further contain a thickening agent, which can improve storage stability, enhance spreadability during application, and reduce stickiness such as an oily feeling, without causing precipitation of the oil derived from Nannochloropsis. The thickening agent increases the viscosity of the topical skin preparation by swelling in a continuous phase of water or oil, and any thickening agent commonly used in topical skin preparations is acceptable. Examples of thickening agents include polysaccharides such as xanthan gum, carrageenan, and Tremella fuciformis polysaccharide; modified polysaccharides such as carboxymethylated glucan, hydroxypropyl methylcellulose, and ethylcellulose; and synthetic polymers such as carboxyvinyl polymers, acyl-modified carboxyvinyl polymers, and sodium polyacrylate.

[0025] As a thickening agent, it is preferable to include xanthan gum, from the viewpoint of improving storage stability, enhancing spreadability during application, and reducing stickiness such as an oily feeling, without causing precipitation of oil derived from nannochloropsis. The amount of thickener is preferably 0.01 to 1% by mass, more preferably 0.05 to 0.7% by mass, and even more preferably 0.1 to 0.3% by mass, in the total composition, from the viewpoint of improving storage stability, improving spreadability during application, and reducing stickiness such as an oily feeling, without causing precipitation of the oil derived from Nannochloropsis.

[0026] The topical skin preparation of the present invention may further contain an oil that is liquid at 25°C in addition to the nannochloropsis-derived oil, which is preferable from the viewpoint of preventing the nannochloropsis-derived oil from precipitation, improving storage stability, improving spreadability during application, reducing stickiness such as an oily feeling, and from the viewpoint of reducing energy consumption and simplifying the manufacturing process. Liquid refers to a substance that has fluidity, and this includes paste-like substances. Examples of liquid oils at 25°C include those commonly used in topical skin preparations, such as hydrocarbon oils, ester oils, ether oils, silicone oils, and higher fatty acids.

[0027] Examples of hydrocarbon oils include squalane, liquid paraffin, liquid isoparaffin, light liquid isoparaffin, heavy liquid isoparaffin, and α-olefin oligomers. The hydrocarbon oil preferably contains one or more selected from squalane and α-olefin oligomers, and more preferably contains squalane.

[0028] Examples of ester oils include monoester oils, diester oils, triester oils, and tetraester oils. Examples of monoester oils include monoesters of aliphatic or aromatic monocarboxylic acids or dicarboxylic acids having 2 to 24 carbon atoms. Specific examples include cetyl 2-ethylhexanoate, cetyl octanoate, isononyl isononanoate, isotridecyl isononanoate, hexyl laurate, isopropyl myristate, octyldodecyl myristate, myristyl myristate, 2-hexyldecyl myristate, isopropyl palmitate, octyl palmitate Examples include thiol, 2-hexyldecyl stearate butyl palmitate, isocetyl stearate, isocetyl isostearate, decyl oleate, isodecyl benzoate, octyl methoxycinnamate, hexyldecyl dimethyloctanoate, cetyl lactate, myristyl lactate, lanolin acetate, 2-ethylhexyl succinate, 2-hexyldecyl adipate, alkyl benzoate (C12-C15), ethylhexyl methoxycinnamate, jojoba oil, etc. The monoester oil preferably contains one or more selected from ethylhexyl methoxycinnamate and jojoba oil, and more preferably contains jojoba oil.

[0029] Examples of diester oils include diesters of dicarboxylic acids having 3 to 18 carbon atoms, and di-fatty acid esters of polyhydric alcohols. Specific examples include propylene glycol dicaprylate, neopentyl glycol dicaprate, glycol distearate, propylene glycol diisostearate, glyceryl diisostearate, glyceryl monomyristate monoisostearate, glyceryl di2-heptylundecanoate, di2-ethylhexyl succinate, diisopropyl sebacate, diisostearyl malate, ethylene glycol di2-ethylhexanoate, diisobutyl adipate, di-2-heptylundecyl adipate, and di-2-ethylhexyl sebacate.

[0030] Examples of triester oils include tri-fatty acid esters of polyhydric alcohols with a valency of 3 or higher, specifically glyceryl triisopalmitate, glyceryl tri-2-heptylundecanoate, trimethylolpropane triethylhexanoate, trimethylolpropane trioctanoate, tri(caprylic / capric acid)glycerin, glyceryl trioleate, glyceryl tri-2-ethylhexanoate, glyceryl triisostearate, and also vegetable oils such as olive oil, macadamia nut oil, meadowfoam oil, castor oil, safflower oil, sunflower oil, avocado oil, canola oil, apricot kernel oil, rice germ oil, and rice bran oil. The triester oil preferably contains one or more selected from vegetable oils, more preferably contains one or more selected from olive oil and macadamia nut oil, and even more preferably contains olive oil.

[0031] Examples of tetraester oils include tetra fatty acid esters of polyhydric alcohols with four or more valencies, specifically tetra(behenic acid / benzoic acid / ethylhexanoic acid) pentaerythritol, tetraethylhexanoate pentaerythritol, tetraoctanoate pentaerythritol, and tetra-2-ethylhexanoate pentaerythritol.

[0032] Examples of ether oils include dialkyl ethers, specifically dihexyl ether, dicaprylyl ether, and cetyl-1,3-dimethylbutyl ether.

[0033] Examples of silicone oils include volatile and non-volatile linear dimethylpolysiloxanes such as dimethylpolysiloxane (1 cs), dimethylpolysiloxane (1.5 cs), dimethylpolysiloxane (2 cs), dimethylpolysiloxane (6 cs), dimethylpolysiloxane (20 cs), and dimethylpolysiloxane (100 cs); branched siloxanes such as methyl trimethicone, tris(trimethylsilyl)methylsilane, and tetrakis(trimethylsilyl)silane; cyclic dimethylsiloxanes such as octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, and dodecamethylcyclohexasiloxane; methylphenylpolysiloxanes such as cross-linked methylpolysiloxane, network methylpolysiloxane, methyl trimethicone, and diphenylsiloxyphenyl trimethicone; and higher alcohol-modified organopolysiloxanes. The silicone oil preferably contains one or more selected from linear dimethylpolysiloxane and methylphenylpolysiloxane, more preferably contains one or more selected from non-volatile linear dimethylpolysiloxane and methylphenylpolysiloxane, and even more preferably contains methylphenylpolysiloxane.

[0034] Examples of high-grade fatty acids include oleic acid, isostearic acid, and undecylenic acid.

[0035] As a liquid oil at 25°C, it is preferable to include one or more selected from hydrocarbon oils, ester oils, ether oils, and silicone oils, more preferably containing hydrocarbon oils, ester oils, and silicone oils, even more preferably containing one or more selected from hydrocarbon oils, monoester oils, triester oils, and silicone oils, even more preferably containing one or more selected from squalane, ethylhexyl methoxycinnamate, olive oil, macadamia nut oil, jojoba oil, and methylphenylpolysiloxane, and especially preferable to include one or more selected from squalane, olive oil, jojoba oil, and methylphenylpolysiloxane.

[0036] The content of the liquid oil at 25°C is preferably 0.1 to 95% by mass, more preferably 0.5 to 80% by mass, and even more preferably 1 to 75% by mass, from the viewpoint of preventing precipitation of the oil derived from Nannochloropsis, improving storage stability, improving spreadability during application, and reducing stickiness such as an oily feeling. When the topical skin preparation of the present invention is a non-aqueous oil preparation, the content of the liquid oil at 25°C is preferably 50 to 95% by mass of the total composition, more preferably 60 to 93% by mass, and even more preferably 85 to 92% by mass. When the topical skin preparation of the present invention is an emulsified preparation, the content of the liquid oil at 25°C is preferably 0.1 to 80% by mass of the total composition, more preferably 0.5 to 78% by mass, and even more preferably 1 to 75% by mass.

[0037] In addition to the above-mentioned components, the topical skin preparation of the present invention may contain components commonly used in topical skin preparations, such as other oily components, monohydric alcohols such as ethanol, preservatives, antioxidants, pigments, pH adjusters, fragrances, plant extracts, colorants, powders, UV absorbers, moisturizers, blood circulation promoters, cooling agents, antiperspirants, bactericides, skin activators, and the like.

[0038] The topical skin preparation of the present invention can be manufactured by conventional methods. For example, it can be manufactured by appropriately mixing predetermined components, and can be manufactured by uniformly mixing and dispersing all components regardless of the order in which they are mixed. In particular, it can also be prepared by low-energy manufacturing, which involves stirring with minimal mechanical force in an environment of 40°C or below.

[0039] The topical skin preparation of the present invention can be applied to cosmetics, quasi-drugs such as medicated cosmetics, and pharmaceuticals, and is suitable as a cosmetic, and more suitable as a skin care cosmetic.

[0040] The present invention can be applied to various dosage forms of topical skin preparations, including solubilized preparations, emulsified preparations, oil preparations, and balm preparations. It is preferably applied to emulsified preparations and oil preparations, and more preferably to oil preparations. The oil preparation is preferably non-aqueous, and in the case of non-aqueous preparations, the content of aqueous components is preferably 1% by mass or less of the total composition, more preferably 0.5% by mass or less, even more preferably 0.1% by mass or less, and even more preferably substantially no aqueous components. [Examples]

[0041] Manufacturing Example 1 (1) Culturing, harvesting, and pretreatment of Nannochloropsis oceanica strain NIES2145: The culture of Nannochloropsis oceanica strain NIES2145 was performed in f / 2 liquid medium (75 mg NaNO3, 6 mg NaH2PO4·2H2O, 0.5 μg vitamin B12). 12 Using 0.5 μg biotin, 100 μg thiamine, 10 mg Na2SiO3·9H2O, 4.4 mg Na2EDTA·2H2O, 3.16 mg FeCl3·6H2O, 12 μg FeCl3·6H2O, 21 μg ZnSO4·7H2O, 180 μg MnCl2·4H2O, 7 μg CuSO4·5H2O, and 7 μg Na2MoO4·2H2O (1 L of artificial seawater), at a temperature of 25 degrees Celsius, a carbon dioxide concentration of 0.3%, a 12-hour light-dark cycle, osmosis at 120 rpm, and a light intensity of approximately 300 μmol photons / m². 2The culture was performed in an artificial climate chamber under the conditions of / s. The culture medium cultured for 2 weeks under the above conditions was used as the pre-culture medium. For the main culture, 10 times the volume of the pre-culture medium was used and cultured for 3 weeks, and the resulting culture medium was used as the oil extraction sample. The culture solution obtained above was centrifuged (9000 rpm, 20 minutes) to collect the algal cells. The collected algal cells were dried at 50°C, and then pre-treated by crushing the cells using an electric mill.

[0042] (2) Preparation of crude oil: (1) The treated algae obtained in (1) were mixed with 20 times the amount (by weight) of hexane and thoroughly stirred to perform hexane extraction. The algae were separated from the hexane solution by suction filtration, and the solvent was distilled using a rotary evaporator to recover the oil. The obtained oil was used as Nannochloropsis-derived extracted oil (crude oil).

[0043] (3) Refining of crude oil: (2) Phosphoric acid (2% of fat) was added to the crude oil obtained in (2), and the mixture was vigorously stirred at 70°C for 30 minutes to remove the gum. Subsequently, NaOH (7% of fat) was added, and the mixture was vigorously stirred at 70°C for 30 minutes to remove the acid. The gum was separated by centrifugation (40°C, 8000 rpm, 30 minutes), and the removed fat was recovered. Distilled water (10% oil to fat) was added to the degummed oil, and the mixture was vigorously stirred at 70°C for 30 minutes. The aqueous layer was then removed by centrifugation (40°C, 8000 rpm, 30 minutes), and the mixture was washed with water. The washing was performed twice. The oil and fat after washing were dehydrated at 70°C and 90 hPa for 30 minutes. After dehydration, activated clay (3% to oil and fat) was added, and the mixture was vigorously stirred at 100°C and 90 hPa for 30 minutes to decolorize it. After the reaction, the mixture was filtered to separate the activated clay and oil and fat, obtaining the decolorized oil and fat. Steam (3% / h) was blown into the decolorized oil and fat, and distillation was performed to deodorize it. The reaction was carried out at 210°C and 150 pa with vigorous stirring for 1 hour to obtain nannochloropsis-derived oil (refined oil).

[0044] Test example For each component shown in Table 1, the state and stability (color change) at various temperatures were evaluated. The results are shown in Table 1.

[0045] (1) Appearance at each temperature: One g of each component was placed in a glass bottle, sealed, and placed in constant temperature baths at 20°C, 30°C, 40°C, and 45°C. After 4 hours, the appearance (presence or absence of precipitates) was observed visually.

[0046] (2) Stability (discoloration): 50g of each component was placed in a glass bottle, sealed, and placed in a constant temperature bath at 45°C. After one month, it was removed and left at 25°C for 6 hours, after which its appearance (presence or absence of discoloration) was observed visually.

[0047] [Table 1]

[0048] The degummed and decolorized nannochloropsis-derived oil did not discolor at high temperatures and exhibited excellent stability. On the other hand, the nannochloropsis-derived oil that had not been degummed or decolorized showed discoloration at high temperatures and was insufficient in terms of stability.

[0049] Examples 1-7, Comparative Examples 1-13 A topical skin preparation (oil-based beauty serum) with the composition shown in Table 2 was manufactured, and its spreadability upon application, lack of oiliness (stickiness), and stability (precipitation, two-phase separation, discoloration) were evaluated. The results are also shown in Table 2.

[0050] (Manufacturing method) All ingredients were mixed at 40°C and cooled to 32°C while stirring to obtain a topical skin preparation (oil serum).

[0051] (Evaluation method) (1) Spreadability and non-greasy feel (non-stickiness) when applied: One expert evaluator applied approximately 0.4g of each topical skin preparation to the skin and evaluated its spreadability upon application and the absence of oiliness (stickiness) after absorption, using the following four-point scale.

[0052] (1-1) Spread when applied: 4: It stretches well. 3: It stretches fairly well. 2: The growth rate is somewhat poor. 1: The growth is clearly poor.

[0053] (1-2) Lack of oiliness (stickiness) after it has been absorbed into the skin: 4: Does not feel oily. 3: It feels almost oily. 2: It feels oily. 1: I feel a strong oily sensation.

[0054] (2) Stability: Each topical skin preparation (50g) was placed in a glass bottle, sealed, and stored at 25°C for one month. After storage, its appearance (precipitation / two-phase separation) and appearance (discoloration) were visually evaluated on the following four-point scale.

[0055] (2-1) Stability (precipitation / two-phase separation): 4: There is no precipitation whatsoever, and no two-phase separation of the liquid. 3: There is a very slight precipitate, but no two-phase separation of the liquid. 2: Clear precipitation or two-phase separation of the liquid is present. 1: Precipitation has occurred, and the entire composition has solidified.

[0056] (2-2) Stability (discoloration): 4: No change since saving began. 3: There is a slight change in color from the start of storage. 2: There is a slight change in color from the time storage began. 1: There is a clear change in color from the time storage began.

[0057] [Table 2]

[0058] As shown in Table 2, all of the topical skin preparations in the examples had a good feel and excellent stability. In contrast, when using nannochloropsis-derived oil (crude oil) that had not been degummed or decolorized, or water-soluble nannochloropsis extract, it was not possible to obtain a stable topical skin preparation. Furthermore, when using other solid fats such as shea butter, it was not possible to obtain a topical skin preparation with good stability and feel.

[0059] Examples 8-12, Comparative Examples 14-16 Oil-in-water emulsion cosmetics (oil-in-water emulsion beauty serums) with the compositions shown in Table 3 were prepared, and their spreadability upon application, lack of oiliness (stickiness), and stability (precipitation and two-phase separation) were evaluated in the same manner as in Examples 1 to 7. The results are also shown in Table 3.

[0060] (Manufacturing method) After heating and stirring phases A and B separately at 40°C, phase B was added to phase A and mixed, and the mixture was cooled to 25°C while stirring to obtain an oil-in-water emulsion cosmetic (oil-in-water emulsion beauty serum).

[0061] [Table 3]

[0062] As shown in Table 3, all of the oil-in-water emulsion cosmetics in the examples had a good feel and excellent stability. In contrast, when other solid fats such as shea butter were used, it was not possible to obtain cosmetics with good spreadability upon application, lack of oiliness (stickiness), and stability (precipitation / two-phase separation).

[0063] Example 13 In the same manner as in Examples 8-12, water-in-oil emulsion cosmetics (water-in-oil emulsion serums) with the compositions shown in Table 4 were prepared, and their spreadability upon application, lack of oiliness (stickiness), and stability (precipitation and two-phase separation) were evaluated. The results are also shown in Table 4.

[0064] [Table 4]

[0065] As shown in Table 4, the obtained water-in-oil emulsion cosmetic (water-in-oil emulsion beauty serum) exhibited excellent spreadability upon application, lack of oiliness (stickiness), and stability (precipitation and two-phase separation).

[0066] Prescription Examples 1-10 Topical skin preparations with the compositions shown in Tables 5-14 were manufactured. All of the resulting topical skin preparations spread well when applied, were non-greasy (non-sticky), did not precipitate or separate into two phases, and exhibited excellent stability.

[0067] [Table 5]

[0068] [Table 6]

[0069] [Table 7]

[0070] [Table 8]

[0071] [Table 9]

[0072] [Table 10]

[0073] [Table 11]

[0074] [Table 12]

[0075] [Table 13]

[0076] [Table 14]

[0077] *1: Manufactured by Nippon Fine Chemical Co., Ltd., ECOLANO CLE-NH, *2: Manufactured by Nippon Surfactant Co., Ltd., NIKKOL Sugar Squalane, *3: Croda Japan Co., Ltd., Cropure OL-LQ-(JP) *4: Manufactured by Dow Toray, DOWSIL FZ-209(-G) *5: Manufactured by Nippon Seika Co., Ltd., PRESOME RK-2) *6: Manufactured by Nippon Seika Co., Ltd., PLANDOOL-MAS, *7: Kikkoman Biochemifa Co., Ltd., Hyaluronic Acid FCH (FCH-SU) *8: Manufactured by Ichimaru Falcos, Immunotect B, *9: Dismutin-JPF, manufactured by DSM Nutritional Products. *10: Manufactured by Toyobo Co., Ltd., Surf Mellow-BBG(III)

Claims

1. A method for producing a topical skin preparation, comprising a pre-degummed and decolorized oil derived from Nannochloropsis oceanica.

2. A method for producing a topical skin preparation according to claim 1, wherein Nannochloropsis oceanica is cultured in a photoreactor.

3. Furthermore, a method for producing a topical skin preparation according to claim 1 or 2, comprising incorporating an oil that is liquid at 25°C.

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