Cosmetic composition and process for its preparation

Abstract

To provide a cosmetic composition using a natural pigment and excellent in luminescence.SOLUTION: The cosmetic composition contains a natural pigment and an alkyl galactoside having a 4-22C alkyl group. The method for producing the cosmetic composition includes a step of mixing a natural pigment with a crystal of an alkyl galactoside having a 4-22C alkyl group.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to cosmetic compositions. [Background technology]

[0002] Conventionally, techniques for solubilizing pigments in micelles formed by surfactants have been known. For example, Patent Document 1 proposes a method for stabilizing anthocyanin pigments, which comprises blending one or two surfactants selected from the group consisting of glycerin fatty acid esters, sucrose fatty acid esters, sorbitan fatty acid esters, polyglycerin fatty acid esters, propylene glycol fatty acid esters, calcium stearoyl lactylate, sodium alkyl sulfate, soybean phospholipids, lysolecithin, and chondroitin sulfate (salts) with the anthocyanin pigments. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-064531 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, there has been an increasing demand for naturally derived surfactants and natural colorants as cosmetic compositions. However, the technology of Patent Document 1 leaves room for improvement in terms of luminescence. For this reason, there has been a demand for cosmetic compositions that use natural colorants and have excellent luminescence properties. [Means for solving the problem]

[0005] The present invention can be realized as the following aspects.

[0006] (1) According to one aspect of the present invention, there is provided a cosmetic composition. This cosmetic composition contains a natural colorant and an alkyl galactoside having an alkyl group having from 4 to 22 carbon atoms. The cosmetic composition of this aspect has excellent luminescence.

[0007] (2) In the cosmetic composition described in (1) above, the number of carbon atoms in the alkyl group of the alkyl galactoside may be from 4 to 20. The cosmetic composition in this form has better luminescence.

[0008] (3) In the cosmetic composition according to (1) or (2), the natural colorant may contain a curcuminoid compound. The cosmetic composition in this form has excellent luminescence.

[0009] (4) According to another aspect of the present disclosure, there is provided a method for producing a cosmetic composition. This method for producing a cosmetic composition includes a step of mixing a natural colorant with a crystal of an alkyl galactoside having an alkyl group having 4 to 22 carbon atoms. This method for producing a cosmetic composition can produce a cosmetic composition with excellent luminescence.

[0010] (5) In the method for producing a cosmetic composition according to (4) above, the number of carbon atoms in the alkyl group of the alkyl galactoside may be from 4 to 20. The cosmetic composition of this form has better luminescence.

[0011] (6) The method for producing a cosmetic composition according to (4) or (5) above may include a first step of incorporating the natural colorant into micelles of the alkyl galactoside having an alkyl group containing 6 to 12 carbon atoms at a temperature of 30° C. to 90° C., and a second step of obtaining a hydrogel after the first step by cooling to a temperature lower than that of the first step. This form of the method for producing a cosmetic composition allows the production of a luminescent hydrogel as a cosmetic composition.

[0012] (7) The method for producing a cosmetic composition according to (6) above may further include a third step of obtaining a solid by filtering the hydrogel after the second step. This form of cosmetic composition allows the production of a solid cosmetic composition with excellent light-emitting properties.

[0013] (8) The method for producing a cosmetic composition according to (4) or (5) above may include a step A in which the natural colorant is incorporated into the alkyl galactoside crystals having an alkyl group having from 6 to 22 carbon atoms in oil dispersed therein at a temperature of from 60° C. to 150° C. This form of the method for producing a cosmetic composition allows the production of a luminous oil as a cosmetic composition.

[0014] (9) The method for producing a cosmetic composition according to (8) above may further include a step B of obtaining a solid by filtering the alkyl galactoside crystals incorporating the natural colorant after the step A. This form of cosmetic composition allows the production of a solid cosmetic composition with excellent luminescence.

[0015] The present invention can be realized in various forms, such as a cosmetic product containing a cosmetic composition, or use of an alkyl galactoside for producing a cosmetic composition. [Brief explanation of the drawings]

[0016] [Figure 1] Fluorescence microscope image of the curcumin-containing luminescent hydrogel of Example 1. [Figure 2] 1 shows the emission spectrum of the curcumin-containing luminescent hydrogel of Example 1. [Figure 3] 1 shows the emission spectrum of the curcumin-containing luminescent powder of Example 2. [Figure 4] Fluorescence microscope image of curcumin-containing luminescent insoluble matter in Example 3. [Figure 5] 1 shows the emission spectrum of the curcumin-containing luminescent powder of Example 3. [Figure 6] Fluorescence microscope image of curcumin-containing luminescent insoluble matter in Example 4. [Figure 7] 1 shows the emission spectrum of the curcumin-containing luminescent powder of Example 4. [Figure 8] Fluorescence microscope image of the bisdemethoxycurcumin-containing luminescent hydrogel of Example 7. [Figure 9] Emission spectrum of the bisdemethoxycurcumin-containing luminescent hydrogel of Example 7. [Figure 10] 1 shows the emission spectrum of the bisdemethoxycurcumin-containing luminescent powder of Example 8. [Figure 11] Fluorescence microscope image of bisdemethoxycurcumin-containing luminescent insoluble matter in Example 9. [Figure 12] Emission spectrum of the bisdemethoxycurcumin-containing luminescent powder of Example 9. [Figure 13] Fluorescence microscope image of bisdemethoxycurcumin-containing luminescent insoluble matter in Example 10. [Figure 14] Emission spectrum of the bisdemethoxycurcumin-containing luminescent powder of Example 10. [Figure 15] FIG. 1 is an explanatory diagram showing the results of powder X-ray diffraction in Examples 16 to 18. [Figure 16] FIG. 10 is an explanatory diagram showing the results of NMR in Example 16. [Figure 17] Emission spectrum of the powder of Example 16. DETAILED DESCRIPTION OF THE INVENTION

[0017] According to one embodiment of the present disclosure, there is provided a cosmetic composition. This cosmetic composition includes a natural colorant and an alkyl galactoside having an alkyl group having from 4 to 22 carbon atoms. The cosmetic composition of the present disclosure has excellent luminescence properties.

[0018] In this disclosure, "natural pigments" refers to pigments that can be extracted from animals or plants. Therefore, they are not limited to pigments actually extracted from animals or plants, but may also be pigments obtained by chemical synthesis as long as their molecular structure is the same as that of naturally occurring pigments. Natural pigments are preferably water-insoluble. In this disclosure, "water-soluble" refers to a solubility of 1 g / kg or more in water at 25°C, and "water-insoluble" refers to a solubility of less than 1 g / kg in water at 25°C. Examples of water-insoluble natural pigments include, but are not limited to, curcuminoid compounds (curcumin, bisdemethoxycurcumin, demethoxycurcumin, etc.), chlorophyll, cyanidin, quercetin, luteolin, β-carotene, coenzyme Q10, turmeric pigments, flavonoid pigments, carotenoid pigments, porphyrin pigments, annatto pigments, safflower yellow, phycocyanin pigments, and Lithospermum Root pigments. Natural pigments may be used singly or in combination. The natural pigment preferably includes a curcuminoid compound.

[0019] The alkyl galactosides having an alkyl group having 4 to 22 carbon atoms (hereinafter simply referred to as "alkyl galactosides") are not particularly limited, but from the viewpoint of light-emitting properties, the number of carbon atoms in the alkyl group is preferably 4 to 20 carbon atoms, more preferably 6 to 18 carbon atoms, and even more preferably 6 to 12 carbon atoms. The alkyl group may be linear or branched, but from the viewpoint of light-emitting properties, linear is preferred. The alkyl group may be saturated or unsaturated, but from the viewpoint of light-emitting properties, saturated alkyl is preferred. More specifically, the alkyl galactosides are preferably at least one selected from the group consisting of hexyl galactoside, heptyl galactoside, octyl galactoside, nonyl galactoside, decyl galactoside, undecyl galactoside, and dodecyl galactoside. From the viewpoint of luminescence, the alkyl galactoside is preferably alkyl β-D-galactoside, but may also be alkyl α-D-galactoside, alkyl β-L-galactoside, or alkyl α-L-galactoside. One type of alkyl galactoside may be used alone, or two or more types may be used in combination.

[0020] The cosmetic composition of the present disclosure may be in any form, including, but not limited to, a solid, a gel, a sol, a liquid, and the like. Examples of solid forms include, but are not limited to, a powder, a granule, and the like. The luminescence quantum yield of the cosmetic composition is preferably, but not limited to, 3% or more, more preferably 5% or more, and even more preferably 10% or more. For example, in a gel-type cosmetic composition, the luminescence quantum yield is preferably 5% or more, more preferably 10% or more, and even more preferably 15% or more. Furthermore, for example, in a solid cosmetic composition, the luminescence quantum yield is preferably 15% or more, more preferably 20% or more, even more preferably 25% or more, even more preferably 30% or more, even more preferably 35% or more, and especially preferably 40% or more. The luminescence quantum yield can be determined using an integrating sphere by dividing the number of photons emitted from a sample as luminescence by the number of photons absorbed by the sample.

[0021] The cosmetic composition according to the present disclosure exhibits excellent luminescence. The mechanism by which this occurs is unclear, but it is thought that when prepared in water, the natural dye is incorporated into micelles formed by alkyl galactoside. When prepared in oil, the mechanism by which this occurs is unclear, but it is thought that the natural dye is incorporated during adsorption or recrystallization on the surface of an insoluble solid.

[0022] The method for producing the cosmetic composition of the present embodiment is not particularly limited, but it can be produced, for example, by the method described below. According to another aspect of the present disclosure, there is provided a method for producing a cosmetic composition.

[0023] The method for producing a cosmetic composition according to the present disclosure includes a step of mixing a natural pigment with a crystal of an alkyl galactoside having an alkyl group having from 4 to 22 carbon atoms. Examples of the natural pigment include the same pigments as those described above, and examples of the crystal of an alkyl galactoside having an alkyl group having from 4 to 22 carbon atoms include the alkyl galactoside described above.

[0024] As an example of a method for producing the cosmetic composition of the present disclosure, a method for incorporating a natural colorant into an alkyl galactoside in water will be described below.

[0025] From the viewpoint of luminescence, the temperature in the mixing step is preferably 30° C. or higher and 90° C. or lower, more preferably 40° C. or higher and 80° C. or lower. In the mixing step, stirring or ultrasonic irradiation is preferably performed.

[0026] The mixing step may include mixing a solution containing an alkyl galactoside with a saturation amount or more of a natural colorant. This method allows a luminescent substance to be precipitated, resulting in the production of a luminescent cosmetic composition. Furthermore, this method allows the omission of a step requiring a temperature change, thereby preventing the cosmetic composition production process from becoming too complicated. While the mechanism by which this method allows the production of a luminescent cosmetic composition is not entirely clear, it is possible to cite the possibility that precipitation occurs as a result of excessive incorporation of the natural colorant into micelles formed by the alkyl galactoside.

[0027] The mixing step may include a step (hereinafter also referred to as "first step") of incorporating the natural dye into micelles of alkyl galactoside having an alkyl group having 6 to 12 carbon atoms at a temperature of 30 to 90°C. From the viewpoint of luminescence, the temperature in the first step is preferably 40 to 80°C.

[0028] After the first step, a second step may be performed in which the mixture is cooled to a temperature lower than that of the first step to obtain a hydrogel. That is, the method for producing a cosmetic composition may include a first step in which a natural colorant is incorporated into micelles of an alkyl galactoside having an alkyl group containing 6 to 12 carbon atoms at a temperature of 30°C to 90°C, and a second step in which the mixture is cooled to a temperature lower than that of the first step to obtain a hydrogel. The temperature of the second step is not particularly limited as long as it is lower than that of the first step. From the viewpoint of light emission, however, it is preferably at least 10°C lower than that of the first step, more preferably at least 20°C lower, and even more preferably at least 30°C lower. Furthermore, from the viewpoint of light emission, the temperature of the second step is preferably at least -20°C to 50°C, more preferably at least 0°C to 40°C, and even more preferably at least 3°C ​​to 30°C. Although the mechanism by which luminescent hydrogels can be produced by this method is unclear, it is believed that natural dyes are incorporated into micelles formed by alkyl galactoside, and that cooling results in the formation of a luminescent solid with a fibrous structure, resulting in hydrogelation. Furthermore, the hydrogel reversibly changes back to a micellar solution when heated. The luminescence quantum yield of the hydrogel-like cosmetic composition obtained by the second step is not particularly limited, but is preferably 5% or higher, more preferably 10% or higher, and even more preferably 15% or higher.

[0029] The method for producing a cosmetic composition may include a third step after the second step, in which the hydrogel is filtered to obtain a solid. The filtration method is not particularly limited, but examples thereof include filter filtration and Kiriyama filtration. The filter filtration is not particularly limited, but examples thereof include membrane filter filtration. The solid cosmetic composition obtained by the third step has excellent luminescence. The form of the solid cosmetic composition obtained by the third step is not particularly limited, but examples thereof include powder, granules, and particles. The luminescence quantum yield of the solid cosmetic composition obtained by the third step is not particularly limited, but is preferably 15% or more, more preferably 20% or more, even more preferably 25% or more, even more preferably 30% or more, even more preferably 35% or more, and particularly preferably 40% or more.

[0030] As an example of a method for producing the cosmetic composition of the present disclosure, a method for incorporating a natural pigment into an alkyl galactoside in oil will be described below.

[0031] The step of mixing in oil may include a step of incorporating a natural dye into alkyl galactoside crystals at a temperature of 60°C to 150°C in the oil in which alkyl galactoside crystals having an alkyl group having 6 to 22 carbon atoms are dispersed (hereinafter also referred to as "step A"). From the viewpoint of luminescence, the temperature in step A is preferably 65°C or higher, and more preferably 70°C or higher. Furthermore, from the viewpoint of reducing energy consumption, the temperature in step A is preferably 120°C or lower, and more preferably 90°C or lower. In step A, stirring or ultrasonic irradiation is preferably performed.

[0032] The oil used in step A is not particularly limited and may be, for example, liquid oils, hydrocarbon oils, ester oils, silicone oils, etc., but preferably contains liquid oils. One type of oil may be used alone, or two or more types may be used in combination. Turmeric extract may also be used as the oil for dissolving curcumin or bisdemethoxycurcumin.

[0033] The liquid oils and fats are not particularly limited, but examples thereof include emu oil, avocado oil, camellia oil, turtle oil, macadamia nut oil, corn oil, mink oil, olive oil, rapeseed oil, egg yolk oil, sesame oil, persic oil, wheat germ oil, camellia oil, castor oil, linseed oil, safflower oil, cottonseed oil, perilla oil, meadowfoam oil, soybean oil, peanut oil, tea seed oil, Japanese kaya oil, rice bran oil, Chinese tung oil, Japanese tung oil, jojoba oil, germ oil, triglycerin, glycerin trioctanoate (triethylhexanoin), glycerin triisopalmitate, and the like.

[0034] The hydrocarbon oil is not particularly limited, but examples thereof include liquid paraffin, pristane, paraffin, squalene, petrolatum, hexadecane, heptane, and hexane.

[0035] The ester oil is not particularly limited, but examples thereof include isopropyl myristate, cetyl octanoate, octyldodecyl myristate, isopropyl palmitate, butyl stearate, hexyl laurate, myristyl myristate, decyl oleate, hexyldecyl dimethyloctanoate, isocetyl stearate, isocetyl isostearate, ethylene glycol di-2-ethylhexanoate, neopentyl glycol dicaprate, diisostearyl malate, glycerin di-2-heptylundecanoate, trimethylolpropane tri-2-ethylhexanoate, trimethylolpropane triisostearate, pentaneerythritol tetra-2-ethylhexanoate, glycerin tri-2-ethylhexanoate, triisostearate, Examples of suitable oils include methylolpropane, cetyl 2-ethylhexanoate, 2-ethylhexyl palmitate, glycerin trimyristate, tri-2-heptylundecanoic acid glyceride, oleic acid oil, cetostearyl alcohol, acetoglyceride, 2-heptylundecyl palmitate, cetyl palmitate, diisobutyl adipate, N-lauroyl-L-glutamic acid-2-octyldodecyl ester, di-2-heptylundecyl adipate, ethyl laurate, di-2-ethylhexyl sebacate, 2-hexyldecyl myristate, 2-hexyldecyl palmitate, 2-hexyldecyl adipate, diisopropyl sebacate, 2-ethylhexyl succinate, ethyl acetate, butyl acetate, amyl acetate, and triethyl citrate.

[0036] The silicone oil is not particularly limited, but examples thereof include linear siloxanes, cyclic siloxanes, etc. The linear siloxane is not particularly limited, but examples thereof include dimethylpolysiloxane, methylphenylpolysiloxane, methylhydrogenpolysiloxane, diphenyltrimethicone, diphenylsiloxyphenyltrimethicone, etc. The cyclic siloxane is not particularly limited, but examples thereof include pentasiloxane, decamethylpolysiloxane, dodecamethylpolysiloxane, tetramethyltetrahydrogenpolysiloxane, etc.

[0037] Step A may be followed by Step B, in which the alkyl galactoside crystals incorporating the natural colorant are filtered to obtain a solid. That is, the method for producing a cosmetic composition may include Step A, in which the natural colorant is incorporated into the alkyl galactoside crystals at a temperature of 60°C to 150°C in an oil in which alkyl galactoside crystals having an alkyl group containing 6 to 22 carbon atoms are dispersed, and Step B, in which the alkyl galactoside crystals incorporating the natural colorant are filtered to obtain a solid after Step A. The filtration method is not particularly limited, but examples include filter filtration and Kiriyama filtration. The filter filtration is not particularly limited, but examples include membrane filter filtration. The solid cosmetic composition obtained by Step B has excellent luminescence. The form of the solid cosmetic composition obtained by Step B is not particularly limited, but examples include powder, granules, and particles. [Example]

[0038] The present invention will be explained in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0039] <Test 1: Dye uptake in water> (1) Method Example 1: Preparation of curcumin-containing luminescent hydrogel 0.04 mL of a 0.5 mM ethanol solution of curcumin (Tokyo Chemical Industry Co., Ltd.) was added to a sample tube, and the ethanol was then removed under reduced pressure. 1% by mass of decyl β-D-galactoside (aq., 0.2 mL) was added, and the curcumin was solubilized by 10 minutes of ultrasonic irradiation using an MCS-6 (AS ONE Co., Ltd.) at 50°C. The solution was then allowed to stand at 4°C to prepare a curcumin-containing luminescent hydrogel (Example 1).

[0040] Example 2: Preparation of curcumin-containing luminescent powder The curcumin-containing luminescent hydrogel of Example 1 was filtered through a membrane filter to obtain curcumin-containing luminescent powder (Example 2).

[0041] Example 3: Preparation of luminescent insoluble matter containing curcumin 0.01 mL of a 0.5 mM curcumin (Tokyo Chemical Industry Co., Ltd.) ethanol solution was added to a sample tube, and the ethanol was then distilled off under reduced pressure. 1% by mass of undecyl β-D-galactoside (aq., 0.4 mL) was added, and the curcumin was solubilized by 10 minutes of ultrasonic irradiation using an MCS-6 (AS ONE Co., Ltd.) at 50°C. The solution was then left to stand at 4°C to obtain an insoluble precipitate. The resulting solution was then filtered through a membrane filter to obtain a curcumin-containing luminescent powder (Example 3).

[0042] Example 4: Preparation of curcumin-containing luminescent powder 0.01 mL of a 0.5 mM curcumin (Tokyo Chemical Industry Co., Ltd.) ethanol solution was added to a sample tube, and the ethanol was then distilled off under reduced pressure. 1% by mass dodecyl β-D-galactoside (aq., 0.4 mL) was added, and the curcumin was solubilized by 10 minutes of ultrasonic irradiation using an MCS-6 (AS ONE Co., Ltd.) at 50°C. The solution was then left to stand at 4°C to obtain an insoluble precipitate. The resulting solution was then filtered through a membrane filter to obtain a curcumin-containing luminescent powder (Example 4).

[0043] Example 5: Preparation of curcumin-containing luminescent hydrogel 0.01 mL of a 0.5 mM ethanol solution of curcumin (Tokyo Chemical Industry Co., Ltd.) was added to a sample tube, and the ethanol was then removed under reduced pressure. 10% by mass hexyl β-D-galactoside (aq., 0.4 mL) was added, and the curcumin was solubilized by 10 minutes of ultrasonic irradiation using an MCS-6 (AS ONE) at 50°C. The solution was then allowed to stand at 4°C to prepare a curcumin-containing luminescent hydrogel (Example 5).

[0044] Example 6: Preparation of curcumin-containing luminescent powder The curcumin-containing luminescent hydrogel of Example 5 was filtered through a membrane filter to obtain curcumin-containing luminescent powder (Example 6).

[0045] Example 7: Preparation of luminescent hydrogel containing bisdemethoxycurcumin 0.02 mL of a 0.5 mM bisdemethoxycurcumin (Tokyo Chemical Industry Co., Ltd.) ethanol solution was added to a sample tube, and the ethanol was then removed under reduced pressure. 1% by mass of decyl β-D-galactoside (aq., 0.2 mL) was added, and the solution was sonicated for 10 minutes at 50°C using an MCS-6 (AS ONE) to solubilize the bisdemethoxycurcumin. The solution was then allowed to stand at 4°C to prepare a bisdemethoxycurcumin-containing luminescent hydrogel (Example 7).

[0046] Example 8: Preparation of luminescent powder containing bisdemethoxycurcumin The bisdemethoxycurcumin-containing luminescent hydrogel of Example 7 was subjected to Kiriyama filtration to obtain bisdemethoxycurcumin-containing luminescent powder (Example 8) as an insoluble matter.

[0047] Example 9: Preparation of luminescent powder containing bisdemethoxycurcumin 0.01 mL of a 0.5 mM bisdemethoxycurcumin (Tokyo Chemical Industry Co., Ltd.) ethanol solution was added to a sample tube, and the ethanol was then distilled off under reduced pressure. 1% by mass of undecyl β-D-galactoside (aq., 0.4 mL) was added, and the solution was solubilized by ultrasonic irradiation using an MCS-6 (AS ONE Co., Ltd.) at 50°C for 10 minutes. The solution was then left to stand at 4°C to obtain an insoluble precipitate. Further filtration through a membrane filter yielded a bisdemethoxycurcumin-containing luminescent powder (Example 9).

[0048] Example 10: Preparation of luminescent powder containing bisdemethoxycurcumin 0.01 mL of a 0.5 mM bisdemethoxycurcumin (Tokyo Chemical Industry Co., Ltd.) ethanol solution was added to a sample tube, and the ethanol was then distilled off under reduced pressure. 1% by mass dodecyl β-D-galactoside (aq., 0.4 mL) was added, and the solution was solubilized by ultrasonic irradiation using an MCS-6 (AS ONE Co., Ltd.) at 50°C for 10 minutes. The solution was then left to stand at 4°C to obtain an insoluble precipitate. Further filtration through a membrane filter yielded a bisdemethoxycurcumin-containing luminescent powder (Example 10).

[0049] Example 11: Preparation of luminescent hydrogel containing bisdemethoxycurcumin 0.01 mL of a 0.5 mM bisdemethoxycurcumin (Tokyo Chemical Industry Co., Ltd.) ethanol solution was added to a sample tube, and the ethanol was then removed under reduced pressure. 10% by mass of hexyl β-D-galactoside (aq., 0.4 mL) was added, and the solution was sonicated for 10 minutes at 50°C using an MCS-6 (AS ONE) to solubilize the bisdemethoxycurcumin. The solution was then allowed to stand at 4°C to prepare a bisdemethoxycurcumin-containing luminescent hydrogel (Example 11).

[0050] Example 12: Preparation of luminescent powder containing bisdemethoxycurcumin The bisdemethoxycurcumin-containing luminescent hydrogel of Example 11 was filtered through a membrane filter to obtain bisdemethoxycurcumin-containing luminescent powder (Example 12).

[0051] Example 13: Preparation of chlorophyll-containing luminescent hydrogel 0.04 mL of saturated chlorophyll (Tokyo Chemical Industry Co., Ltd.) hexane solution was added to the sample tube, and the hexane was then distilled off under reduced pressure. 1% by mass of decyl β-D-galactoside (aq., 0.4 mL) was added, and the fat-soluble chlorophyll was solubilized by 10 minutes of ultrasonic irradiation using an MCS-6 (AS ONE Co., Ltd.) at 50°C. The mixture was then allowed to stand at 4°C to prepare a fat-soluble chlorophyll-containing luminescent hydrogel (Example 13).

[0052] Example 14: Preparation of chlorophyll-containing luminescent powder The fat-soluble chlorophyll-containing luminescent hydrogel of Example 13 was subjected to Kiriyama filtration to obtain fat-soluble chlorophyll-containing luminescent powder (Example 14) as an insoluble matter.

[0053] Example 15: Preparation of luminescent powder using other natural pigments Pigment-containing powders were prepared in the same manner as in the above examples using cyanidin, quercetin, luteolin, β-carotene, and coenzyme Q10.

[0054] (2) Observation of the crystalline state and confirmation of luminescence The crystalline state of alkyl β-D-galactoside was observed using a fluorescence microscope with excitation at 488 nm for the luminescent hydrogels or luminescent insoluble matter of Examples 1, 3, 4, 7, 9, and 10. The luminescent properties of the luminescent hydrogels, luminescent insoluble matter, and luminescent powders of Examples 1 to 4 and 7 to 10 were also confirmed. To confirm the luminescent properties, the emission spectrum and luminescence quantum yield were measured with an excitation wavelength of 400 nm using a Quantaurus-QY C11347-01 device (Hamamatsu Photonics Co., Ltd.). The luminescent hydrogels or luminescent powders of Examples 5, 6, and 11 to 15 were measured using a microplate reader, and all were confirmed to be luminescent.

[0055] (3) Results Figure 1 is a fluorescence microscope image of the curcumin-containing luminescent hydrogel of Example 1. As shown in Figure 1, fibrous crystals were formed, confirming hydrogelation. The luminescence was due to curcumin, and it was shown that curcumin was incorporated into the fibrous crystals formed by decyl β-D-galactoside.

[0056] Figure 2 shows the emission spectrum of the curcumin-containing luminescent hydrogel of Example 1. As shown in Figure 2, the maximum emission wavelength was around 515 nm, and it was confirmed that the hydrogel exhibited luminescence in the range of 470-620 nm. The luminescence quantum yield was 6% or more when excited at 400 nm.

[0057] Figure 3 shows the emission spectrum of the curcumin-containing luminescent powder of Example 2. As shown in Figure 3, the maximum emission wavelength was around 530 nm, and it was confirmed that the powder exhibited luminescence in the range of 480-640 nm. The luminescence quantum yield was 20% or more when excited at 400 nm.

[0058] Figure 4 is a fluorescence microscope image of the curcumin-containing luminescent insoluble matter in Example 3. As shown in Figure 4, it was confirmed that fibrous and spherical crystal structures were formed, and that a semi-solid was formed. The luminescence was due to curcumin, and it was shown that curcumin was mixed into the fibrous crystals and spherical crystals formed by undecyl β-D-galactoside.

[0059] Figure 5 shows the emission spectrum of the curcumin-containing luminescent powder of Example 3. As shown in Figure 5, the maximum emission wavelength was around 520 nm, and it was confirmed that the powder exhibited luminescence in the range of 470-630 nm. The luminescence quantum yield was 20% or more when excited at 400 nm.

[0060] Figure 6 is a fluorescence microscope image of the curcumin-containing luminescent insoluble matter in Example 4. As shown in Figure 6, it was confirmed that a semi-solid was formed by the formation of spherical crystals. The luminescence was due to curcumin, and it was shown that curcumin was mixed into the fibrous crystals and spherical crystals formed by dodecyl β-D-galactoside.

[0061] Figure 7 shows the emission spectrum of the curcumin-containing luminescent powder of Example 4. As shown in Figure 7, the maximum emission wavelength was around 510 nm, and it was confirmed that the powder exhibited luminescence in the range of 460-610 nm. The luminescence quantum yield was 27% or more when excited at 400 nm.

[0062] Figure 8 is a fluorescence microscope image of the bisdemethoxycurcumin-containing luminescent hydrogel of Example 7. As shown in Figure 8, fibrous crystals were formed, confirming hydrogelation. The luminescence was due to bisdemethoxycurcumin, and it was shown that bisdemethoxycurcumin was incorporated into the fibrous crystals formed by decyl β-D-galactoside.

[0063] Figure 9 shows the emission spectrum of the bisdemethoxycurcumin-containing luminescent hydrogel of Example 7. As shown in Figure 9, the maximum emission wavelength was around 501 nm, and it was confirmed that the gel exhibited luminescence in the range of 480-620 nm. The luminescence quantum yield was 30% or more when excited at 400 nm.

[0064] Figure 10 shows the emission spectrum of the bisdemethoxycurcumin-containing luminescent powder of Example 8. As shown in Figure 10, the maximum emission wavelength was around 530 nm, and it was confirmed that the powder exhibited luminescence in the range of 480-640 nm. The luminescence quantum yield was 40% or more when excited at 400 nm.

[0065] Figure 11 is a fluorescence microscope image of the luminescent insoluble matter containing bisdemethoxycurcumin in Example 9. As shown in Figure 11, it was confirmed that fibers and spherical crystal structures were formed, and a semi-solid was formed. The luminescence was due to bisdemethoxycurcumin, and it was shown that bisdemethoxycurcumin was mixed into the fibers and spherical crystals formed by undecyl β-D-galactoside.

[0066] Figure 12 shows the emission spectrum of the bisdemethoxycurcumin-containing luminescent powder of Example 9. As shown in Figure 12, the maximum emission wavelength was around 500 nm, and it was confirmed that the powder exhibited luminescence in the range of 450-600 nm. The luminescence quantum yield was 40% or more when excited at 400 nm.

[0067] Figure 13 is a fluorescence microscope image of the luminescent insoluble matter containing bisdemethoxycurcumin in Example 10. As shown in Figure 13, it was confirmed that a semi-solid was formed through the formation of fibers and spherical crystal structures. The luminescence was due to bisdemethoxycurcumin, and it was shown that bisdemethoxycurcumin was mixed into the fibers and spherical crystals formed by dodecyl β-D-galactoside.

[0068] Figure 14 shows the emission spectrum of the bisdemethoxycurcumin-containing luminescent powder of Example 10. As shown in Figure 14, the maximum emission wavelength was around 490 nm, and it was confirmed that the powder exhibited luminescence in the range of 450-590 nm. The luminescence quantum yield was 20% or more when excited at 400 nm.

[0069] <Test 2: Dye uptake in oil> (1) Powder preparation method Example 16: Preparation of curcumin-containing luminescent powder 20 mg of decyl β-D-galactoside anhydrate crystals was added to 2.0 mL of saturated curcumin (Tokyo Chemical Industry Co., Ltd.)-glyceryl tri-2-ethylhexanoate (NIKKOL Corporation), followed by 10 minutes of ultrasonic irradiation at 70°C using an MCS-6 (AS ONE Corporation) to adsorb curcumin. The mixture was then allowed to stand at room temperature and filtered using a Kiriyama filter to obtain a curcumin-containing luminescent powder (Example 16) as an insoluble material. During the Kiriyama filter, the insoluble portion was washed three times with glyceryl tri-2-ethylhexanoate.

[0070] Example 17: Preparation of curcumin-containing luminescent powder 20 mg of decyl β-D-galactoside monohydrate crystals were added to 2.0 mL of saturated curcumin (Tokyo Chemical Industry Co., Ltd.)-glyceryl tri-2-ethylhexanoate (NIKKOL Corporation), followed by 10 minutes of ultrasonic irradiation at 70°C using an MCS-6 (AS ONE Corporation) to adsorb curcumin. The mixture was then allowed to stand at room temperature and filtered using a Kiriyama filter to obtain the insoluble curcumin-containing luminescent powder (Example 18). During the Kiriyama filter, the insoluble side was washed three times with glyceryl tri-2-ethylhexanoate.

[0071] Example 18: Preparation of luminescent powder containing bisdemethoxycurcumin 20 mg of decyl β-D-galactoside monohydrate crystals were added to 2.0 mL of saturated bisdemethoxycurcumin (Tokyo Chemical Industry Co., Ltd.)-triolein (Fujifilm Wako Co., Ltd.), followed by 10 minutes of ultrasonic irradiation at 70°C using an MCS-6 (AS ONE) to adsorb bisdemethoxycurcumin. The mixture was then allowed to stand at room temperature and filtered using a Kiriyama filter to obtain bisdemethoxycurcumin-containing luminescent powder (Example 19) as an insoluble material. During the Kiriyama filter, the insoluble portion was washed three times with triolein.

[0072] (2) Powder X-ray diffraction, NMR and luminescence confirmation Powder X-ray diffraction measurements (PXRD) were carried out on the powders of Examples 16 to 18. For the measurements, a RINT-2000 (manufactured by Rigaku Corporation) was used, with CuKα as the radiation source. The same measurements were carried out on the decyl β-D-galactoside hydrate crystals and the decyl β-D-galactoside anhydrate crystals. In addition, the powders of Examples 16 and 17 were subjected to nuclear magnetic resonance spectroscopy ( 1 Analysis was carried out by H-NMR. The powder was dissolved in d6-DMSO solvent and used as a sample, which was measured by nuclear magnetic resonance spectroscopy using an ECA-600 (manufactured by JEOL Ltd.). Furthermore, the luminescence properties of the powders of Examples 16 to 18 were confirmed. To confirm the luminescence properties, the luminescence spectrum was measured at 365 nm excitation using a microplate reader.

[0073] (3) Results Figure 15 is an explanatory diagram showing the results of powder X-ray diffraction for Examples 16 to 18. Figure 15 shows, from top to bottom, the results of powder X-ray diffraction measurement for decyl β-D-galactoside hydrate crystals, decyl β-D-galactoside anhydrate crystals, the powder of Example 16, the powder of Example 17, and the powder of Example 18. As shown in Figure 15, the decyl β-D-galactoside hydrate crystals and the anhydrate decyl β-D-galactoside crystals each showed a peak around 3.7 deg, while the powders prepared in Examples 16 to 18 all showed a new peak around 2.6 deg. This coincides with the peaks observed when decyl β-D-galactoside forms adducts or co-crystals with curcumin or bisdemethoxycurcumin, as previously reported (Ogawa, S., et al., Journal of Oleo Science, 74(8), 689-69 (2025)). This indicates that curcuminoid pigments are mixed into the decyl β-D-galactoside crystals.

[0074] FIG. 16 is an explanatory diagram showing the NMR results for Example 16. As shown in FIG. 16, if the integral of the protons of the -OH groups on the 2-, 3-, and 4-positions of galactose in decyl β-D-galactoside is taken as 1, the integrals of the protons on curcumin contained in the powder of Example 16 were a = 0.13 and c = 0.23. This indicates that the powder of Example 16 contains approximately 0.12 molecules of curcumin per molecule of decyl β-D-galactoside. According to the NMR results for Example 17, the powder of Example 17 was estimated to contain 0.09 molecules of curcumin per molecule of decyl β-D-galactoside. As mentioned above, in the preparation of the powders in Examples 16 and 17, the adsorption procedure was carried out at 70°C. However, the NMR results of the powders prepared by carrying out the adsorption procedure at 25°C instead of 70°C showed that the maximum curcumin content was only 0.02 molecules per molecule of decyl β-D-galactoside. This demonstrates the usefulness of the heating procedure when incorporating dyes into alkyl galactoside crystals.

[0075] Fig. 17 shows the emission spectrum of the powder of Example 16. As shown in Fig. 17, it was confirmed that the powder exhibited luminescence in the range of 450 nm to 700 nm. Similar results were also confirmed for the powders of Examples 17 and 18.

[0076] The present invention is not limited to the above-described embodiments and can be realized in various configurations without departing from the spirit of the present invention. For example, the technical features in the embodiments and examples corresponding to the technical features in each aspect described in the Summary of the Invention section can be appropriately replaced or combined to solve some or all of the above-described problems or achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be deleted as appropriate.

Claims

1. A cosmetic composition comprising: a natural colorant, an alkyl galactoside having an alkyl group having 4 to 22 carbon atoms, A cosmetic composition comprising:

2. The cosmetic composition according to claim 1, the alkyl group of the alkyl galactoside has 4 to 20 carbon atoms; Cosmetic compositions.

3. The cosmetic composition according to claim 1 or 2, The natural pigment comprises a curcuminoid compound. Cosmetic compositions.

4. A method for producing a cosmetic composition, comprising: The method includes a step of mixing a natural colorant with a crystal of an alkyl galactoside having an alkyl group having from 4 to 22 carbon atoms, A method for producing a cosmetic composition.

5. 5. The method for producing a cosmetic composition according to claim 4, the alkyl group of the alkyl galactoside has 4 to 20 carbon atoms; A method for producing a cosmetic composition.

6. 6. The method for producing a cosmetic composition according to claim 4 or 5, a first step of incorporating the natural dye into micelles of the alkyl galactoside having an alkyl group having 6 to 12 carbon atoms at a temperature of 30° C. to 90° C.; a second step of obtaining a hydrogel by cooling the mixture to a temperature lower than that of the first step after the first step; A method for producing a cosmetic composition, comprising:

7. The method for producing a cosmetic composition according to claim 6, further comprising: A third step is included after the second step, in which the hydrogel is filtered to obtain a solid. A method for producing a cosmetic composition.

8. 6. The method for producing a cosmetic composition according to claim 4 or 5, The method includes a step A of incorporating the natural colorant into the alkyl galactoside crystals having an alkyl group having from 6 to 22 carbon atoms in an oil in which the alkyl galactoside crystals are dispersed at a temperature of from 60° C. to 150° C. A method for producing a cosmetic composition.

9. The method for producing a cosmetic composition according to claim 8, further comprising: and after the step A, a step B of filtering the alkyl galactoside crystals incorporating the natural dye to obtain a solid. A method for producing a cosmetic composition.

Images