JP6722033B2 - Skin cosmetics - Google Patents

Description

The present invention relates to skin cosmetics.

As a technique relating to fibrous cellulose, there are techniques described in Patent Documents 1 to 5.
Patent Document 1 (JP-A-2015-157796) describes that cellulose nanofibers can be obtained by defibrating a dispersion fluid of cellulose by a high-pressure injection treatment of 100 to 245 MPa.

In Patent Document 2 (JP 2009-293167 A), a polybasic acid half-esterified cellulose is prepared by semi-esterifying a polybasic acid anhydride into a part of the hydroxyl groups of cellulose to introduce a carboxyl group. , A technique for producing nanofibers by making them fine fibers is described.

Patent Document 3 (Japanese Patent Laid-Open No. 2013-127141) discloses a technique of producing fine fibrous cellulose by treating a fiber raw material containing cellulose with an oxo acid of phosphorus or a salt thereof and then defibrating the cellulose. Have been described.

In addition, Patent Document 1 described above also describes using fibrous cellulose in the field of cosmetics. That is, according to the document, when fibrous cellulose obtained by the method described in the document is used as an emulsifier, the concentration of water and oil is lower than that of a general emulsifier, but the state in which water and oil are not separated over a long period of time. Since it can be maintained, the ratio of extra additives in cosmetics can be reduced.

Patent Document 4 (JP-A-62-39507) describes a skin care cosmetic characterized in that a microfibrillated cellulose and a water-soluble polymer are essentially blended, and it is applied to the face or body. It is described that it is used as a scrub after application.

Further, in Patent Document 5 (JP 2006-240994 A), a cosmetic pack containing polyvinyl alcohol and microfibrillated cellulose as essential components has a film forming property, elongation of a coating film, an appropriate drying speed, It is described that the coating property and good peeling feeling are kept awaited, and the same document describes that the average fiber length of the microfibrillated cellulose is 0.1 to 1.0 mm.

JP, 2005-157796, A JP, 2009-293167, A JP, 2013-127141, A JP-A-62-39507 JP, 2006-240994, A

Here, since the percutaneous absorption of the cosmetic and the active ingredient contained therein follows the concentration gradient between the cosmetic and the skin, high permeability occurs immediately after the cosmetic is applied to the skin, while the skin elapses over time. Penetration into water will decrease.
On the other hand, in recent years, there has been a demand for cosmetics that can be absorbed percutaneously gradually over a long period of time and have a sustained effect of the ingredients.
However, the techniques described in the patent documents mentioned above in the section of background art have not been examined from the viewpoint of enhancing the sustained release effect of the components in the cosmetic when the cosmetic is applied to the skin. Further, conventional cellulose-containing cosmetics have been used in a limited number of applications, such as being used as a detergent or having to be applied as a pack.

Therefore, the present invention provides a skin cosmetic which is excellent in sustained release of the components contained in the cosmetic and can form a film.

The present inventor uses a combination of a cellulose suitable for a cosmetic formulation and a specific hydroxybenzenecarboxylic acid or a derivative thereof as a functional component, so that when the cosmetic is applied to the skin, the functional component It was found that sustained release is exhibited in percutaneous absorption.

That is, according to the present invention,
The following components (A) and (B):
(A) Unmodified fibrous cellulose having an average fiber length of 10 nm or more and less than 0.1 mm,
There is provided a skin cosmetic containing (B) hydroxybenzenecarboxylic acid or a derivative thereof, wherein the component (B) has an IOB value of 0.90 or more and 6.5 or less.

Further, according to the present invention, there is provided a method of using the skin cosmetic, which comprises the step of applying the skin cosmetic of the present invention described above to the skin.

According to the present invention, it is possible to provide a skin cosmetic which is excellent in sustained release of the components contained in the cosmetic and which can form a film.

Hereinafter, embodiments of the present invention will be described.
In this embodiment, the skin cosmetic contains the following components (A) and (B).
(A) Unmodified fibrous cellulose having an average fiber length of 10 nm or more and less than 0.1 mm (B) Hydroxybenzenecarboxylic acid or a derivative thereof, and the component (B) having an IOB value of 0.90 or more and 6.5 or less. is there.

Hereinafter, each component will be described with reference to specific examples. Each component may be used alone or in combination of two or more.
In addition, in the present specification, “skin cosmetics” is also simply referred to as “cosmetics”.

(Component (A))
The component (A) is a natural cellulose microfiber body and is an unmodified cellulose.
Here, unmodified means that hydroxyl groups at the 2-position, 3-position and 6-position of the cellulose skeleton are not intentionally chemically modified by oxidation, etherification, esterification or the like.
The component (A) contains an unavoidable modifying group derived from natural cellulose, which is a raw material of the component (A), specifically a carboxy group at the 2-, 3- and 6-position hydroxyl groups of the cellulose skeleton. But it's okay. Here, as the unavoidable modifying group contained in the natural cellulose, a modifying group derived from a component contained in the plant that is a raw material of the natural cellulose, a modifying group inevitably generated in the process of isolating and purifying the natural cellulose from the plant. Etc., and these modifying groups are, for example, carboxy groups. For example, the natural cellulose which is the raw material of the component (A) may contain about 2 to 100 μmol/g of carboxy groups.

The origin of the cellulose raw material of the component (A) is not limited, and examples thereof include those derived from plant raw materials such as wood fibers (pulp).
The component (A) is obtained, for example, by crushing a cellulose raw material by a mechanical method or the like to obtain a fiber having a predetermined fiber diameter and a specific fiber length. The resulting component (A) is preferably insoluble in water.

The average fiber diameter of the component (A) is a viewpoint of improving the sustained release effect of the component (B), a viewpoint of improving the production stability of the component (A), and a viewpoint of improving the compatibility of the cosmetic with the skin. Therefore, it is preferably 1 nm or more, more preferably 3 nm or more, still more preferably 4 nm or more, even more preferably 8 nm or more, particularly preferably 9 nm or more, particularly preferably 10 nm or more, particularly preferably 15 nm or more, particularly preferably 25 nm. That is all.
From the viewpoint of enhancing dispersibility in a dispersion medium such as water, the average fiber diameter of the component (A) is preferably 10000 nm or less, more preferably 5000 nm or less, still more preferably 200 nm or less, still more preferably 50 nm. The following is particularly preferable, 40 nm or less, particularly preferably 30 nm or less.
Here, the average fiber diameter of the component (A) is measured by the method described below.
As a method for producing such microfibrillar unmodified cellulose, for example, the method described in JP 2012-51991 A can be used.

The average fiber length of the component (A) is 10 nm or more from the viewpoint of enhancing the sustained release effect of the component (B) and improving the sweat resistance and abrasion resistance of the cosmetic applied to the skin, The thickness is preferably 50 nm or more, more preferably 300 nm or more, further preferably 500 nm or more, even more preferably 1000 nm or more, and particularly preferably 1500 nm or more.
Further, from the viewpoint of enhancing the dispersibility of the component (A) in a dispersion medium such as water, the average fiber length of the component (A) is less than 0.1 mm (100 μm), preferably 90 μm or less, and more preferably It is 50 μm or less, even more preferably 10 μm or less, particularly preferably 5 μm or less, particularly preferably 3 μm or less.
Here, the average fiber length of the fibrous cellulose is measured by the method described below.

Further, the average aspect ratio (average fiber length/average fiber diameter) of the component (A) improves the balance between the sustained release effect of the component (B) and the dispersibility of the component (A) in a dispersion medium such as water. From the viewpoint, it is preferably 10 or more, more preferably 20 or more, still more preferably 50 or more, still more preferably 55 or more, and preferably 5000 or less, more preferably 1000 or less, further preferably 500. Or less, still more preferably 400 or less, particularly preferably 100 or less, particularly preferably 75 or less.

Here, the average fiber diameter, the average fiber length and the average aspect ratio of the component (A) are measured by the following methods. That is, the average fiber diameter and the average fiber length of fibrous cellulose were analyzed using a field emission scanning electron microscope (FE-SEM) for 200 randomly selected fibers, and an arithmetic average of 200 was calculated. To do. The average aspect ratio is calculated by the following formula.
Average aspect ratio = average fiber length / average fiber diameter

Further, the viscosity of the 2 mass% dispersion liquid of the component (A) is preferably 100 mPa·s or more, more preferably 400 mPa·s or more, further preferably from the viewpoint of improving the dispersion stability of the component (A). It is 2500 mPa·s or more, still more preferably 3000 mPa·s or more, preferably 10,000 mPa·s or less, and more preferably 8000 mPa·s or less.
Here, the viscosity of the 2% by mass dispersion liquid of the component (A) is the B-type viscometer (VISCOMETER TVB-10, Toki Sangyo Co., Ltd.) for the 2% by mass dispersion liquid of the component (A) (dispersion medium: water). Manufactured by Rotor No. 4), the rotation speed is 60 rpm, and the rotation speed is 1 minute at 25° C.

From the viewpoint of enhancing the sustained release effect of the component (B), enhancing the dispersion stability of the component (A), and improving the compatibility of the cosmetic with the skin, the component (A) is preferably The average fiber diameter is 25 nm or more and 50 nm or less, and the average fiber length is 1500 nm or more and 3000 nm or less. More preferably, the average fiber diameter and the average fiber length are in the above ranges, and the average aspect ratio is 50 or more 75. The following is more preferable, and the average fiber diameter, the average fiber length, and the average aspect ratio are more preferably in the above ranges, and the viscosity of the 2% by mass dispersion liquid is 2500 mPa·s or more and 8000 mPa·s or less.

As the component (A), microfiber cellulose for general industry is used from the viewpoint of improving the sustained release of the component (B), improving the familiarity of the cosmetic with the skin, and availability. be able to. Specific examples of commercially available microfibrous cellulose include BiNFi-s series cellulose (manufactured by Sugino Machine Ltd.), nanocellulose (manufactured by Daio Paper Co., Ltd.), ACC nanocellulose (manufactured by Chuetsu Pulp Industry Co., Ltd.) and the like.
Further, as the component (A), those having a specific fiber length can be selected and used from those obtained by the method described in JP 2012-51991 A.

The content of the component (A) in the cosmetic is preferably 0.01% by mass or more, and more preferably from the viewpoint of further improving the sustainability of the sustained release effect of the component (B). Is 0.1% by mass or more, more preferably 0.2% by mass or more, even more preferably 0.25% by mass or more, and particularly preferably 0.3% by mass or more.
Further, from the viewpoint of further enhancing the smooth feeling of use of the cosmetic, the content of the component (A) in the cosmetic is preferably 10% by mass or less, and more preferably 5% by mass, based on the entire cosmetic. The amount is preferably 2% by mass or less, more preferably 1.5% by mass or less, still more preferably 1.2% by mass or less.

(Component (B))
The component (B) is hydroxybenzenecarboxylic acid or its derivative. The IOB value of the component (B) is 0.90 or more and 6.5 or less.

In the present embodiment, since the component (B) is contained in the cosmetic together with the component (A), the cosmetic can form a film, and the component (B) is appropriately contained in the cosmetic. It is retained and gradually released. Therefore, for example, immediately after the cosmetic is applied to the skin, the cosmetic gently acts on the skin, and the effect of the cosmetic after application to the skin can be continued with time.

The IOB value of the component (B) is 0.90 or more from the viewpoint of improving the balance between the effect of stably retaining the component (B) in the cosmetic and the effect of the sustained release of the component (B) by the cosmetic. And more preferably 0.95 or more, still more preferably 0.97 or more, even more preferably 1.0 or more, still more preferably 1.2 or more, and 6.5 or less. , More preferably 5.5 or less, still more preferably 4.5 or less, still more preferably 2.0 or less, still more preferably 1.8 or less, and particularly preferably 1.4 or less.
Here, the IOB value (Inorganic-Organic Balance) of the component (B) is the following formula:
IOB value=Σ inorganic value/Σ organic value. In the above formula, for each of the “inorganic value” and the “organic value”, for example, the “organic value” is 20 for one carbon atom in the molecule and 100 for the same hydroxyl group. As described above, based on the "inorganic value" and "organic value" set for each atom and functional group, the "inorganic value" and "organic value" of the atoms and functional groups that make up the organic compound such as an oil agent are calculated. It can be calculated by integrating the "sexuality value" (see Yoshida Koda, "Organic Conceptual Diagram -Basics and Applications-", pages 11 to 17, Sankyo Publishing Co., Ltd., 1984).
When the cosmetic contains a plurality of hydroxybenzenecarboxylic acids or derivatives thereof, the IOB value of the component (B) is a weighted average value obtained by multiplying each IOB value by the mass ratio.

Of the component (B), the hydroxybenzenecarboxylic acid derivative is preferably one or more selected from the group consisting of hydroxybenzenecarboxylic acid salts, hydroxybenzenecarboxylic acid esters and salts thereof, and more preferably 2 One or more selected from the group consisting of -hydroxybenzenecarboxylic acid ester, 4-hydroxybenzenecarboxylic acid ester and salts thereof.
Specific examples of the counter ion constituting the salt include alkali metals such as sodium and potassium; alkaline earth metals such as calcium and magnesium; metals other than the above, such as titanium; ammonium; monoethanolamine, diethanolamine, triethanolamine and the like. And cations derived from basic amino acids such as arginine and lysine, and preferably ions derived from a metal selected from the group consisting of sodium, magnesium and titanium.

As specific examples of the component (B), 2-hydroxybenzenecarboxylic acid (IOB1.89), 2-hydroxybenzenecarboxylic acid dipropylene glycol (IOB1.13), 2-hydroxybenzenecarboxylic acid Na (IOB5.46). , Titanium 2-hydroxybenzenecarboxylate (IOB3.32), methyl 2-hydroxybenzenecarboxylate (IOB1.09), acetamidephenyl 2-hydroxybenzenecarboxylate (IOB1.30), ethylene glycol 2-hydroxybenzenecarboxylate (IOB1.30). IOB1.53), 2-hydroxybenzenecarboxylic acid diphenhydramine (IOB1.52) or other 2-hydroxybenzenecarboxylic acid or a derivative thereof; and 4-hydroxybenzenecarboxylic acid (IOB1.89), 4-hydroxybenzenecarboxylic acid methyl Na (IOB4.22), 4-hydroxybenzenecarboxylic acid ethyl Na (IOB3.75), 4-hydroxybenzenecarboxylic acid propyl Na (IOB3.38), 4-hydroxybenzenecarboxylic acid isobutyl Na (IOB3.21), 4- Butyl hydroxybenzenecarboxylate Na (IOB3.07), methyl 4-hydroxybenzenecarboxylate (IOB1.09), ethyl 4-hydroxybenzenecarboxylate (IOB0.97), isopropyl 4-hydroxybenzenecarboxylate (IOB0.92) 4-hydroxybenzenecarboxylic acid or a derivative thereof.

From the viewpoint of enhancing the sustained release effect of the component (B), the component (B) preferably contains at least one selected from the group consisting of hydroxybenzenecarboxylic acid esters and salts thereof, and more preferably 2 -One or more kinds selected from the group consisting of ethylene glycol hydroxybenzenecarboxylate, methyl 4-hydroxybenzenecarboxylate and ethyl 4-hydroxybenzenecarboxylate, and more preferably methyl 4-hydroxybenzenecarboxylate. And 1 or 2 selected from the group consisting of ethyl 4-hydroxybenzenecarboxylate.

The content of the component (B) in the skin cosmetic is from the viewpoint of improving the balance between the effect of stably retaining the component (B) in the cosmetic and the effect of the cosmetic releasing the component (B) slowly. , Preferably 0.02% by mass or more, more preferably 0.05% by mass or more, further preferably 0.1% by mass or more, still more preferably 0.15% by mass or more, based on the entire cosmetic; , Preferably 10% by mass or less, more preferably 6% by mass or less, further preferably 5% by mass or less, even more preferably 4% by mass or less, and particularly preferably 3% by mass or less.

Further, the mass ratio ((B)/(A)) of the content of the component (B) to the content of the component (A) in the cosmetic is an effect of stably retaining the component (B) in the cosmetic. From the viewpoint of improving the balance between the effect of the cosmetic and the sustained release of the component (B), it is preferably 0.01 or more, more preferably 0.1 or more, further preferably 0.2 or more, and It is more preferably 0.5 or more, preferably 100 or less, more preferably 50 or less, still more preferably 20 or less, and even more preferably 15 or less.

In the present embodiment, from the viewpoint of enhancing the sustained release effect of the component (B), enhancing the dispersion stability of the component (A), and improving the compatibility of the cosmetic with the skin, the components (A) and The combination of (B) preferably has an average fiber diameter of the component (A) of 25 nm or more and 50 nm or less, an average fiber length of the component (A) of 1500 nm or more and 3000 nm or less, and an IOB value of the component (B). Is 0.90 or more and 1.4 or less;
More preferably, the average fiber diameter and the average fiber length of the component (A) are in the above ranges, the average aspect ratio of the component (A) is 50 or more and 75 or less, and the component (B) is 4-hydroxybenzenecarboxylic acid. One or two selected from methyl acidate and ethyl 4-hydroxybenzenecarboxylate;
More preferably, the average fiber diameter, the average fiber length and the average aspect ratio of the component (A) are in the above ranges, and the viscosity of the 2% by mass dispersion is 2500 mPa·s or more and 8000 mPa·s or less, and the component (B). Is one or two selected from methyl 4-hydroxybenzenecarboxylate and ethyl 4-hydroxybenzenecarboxylate.

In this embodiment, the cosmetic may contain components other than the above.
For example, the cosmetic may contain a dispersion medium such as water. The content of the dispersion medium such as water can be, for example, the balance of the cosmetic except components other than water.

In addition, the cosmetic may contain a solvent other than water, and examples of such a solvent include alcohols having 1 to 4 carbon atoms such as ethanol and 2-propanol. From the viewpoint of improving the followability to the movement of the film formed by applying the cosmetic of the present embodiment to the skin, the content of the alcohol having 1 to 4 carbon atoms in the cosmetic is Is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, still more preferably 1% by mass or more, preferably 10% by mass or less, more preferably 8% by mass or less. , And more preferably 5 mass% or less.

In addition, in the present embodiment, the cosmetic contains a large amount of vitamins, deodorants, antiperspirants, cooling agents, fragrances, warming agents, glycerin, etc. within a range where a sustained release effect of the component (B) can be obtained. If necessary, components other than the components (A) and (B), such as a polyhydric alcohol or other moisturizers, oils, and pH adjusters, which are usually added to cosmetics, may be included.
From the viewpoint of improving the followability to the movement of the film formed by applying the cosmetic of the present embodiment to the skin, the content of the polyhydric alcohol in the cosmetic is preferably 0. 1% by mass or more, more preferably 1% by mass or more, further preferably 2% by mass or more, preferably 10% by mass or less, more preferably 8% by mass or less, further preferably 6% by mass. It is as follows.

Next, a method for manufacturing a cosmetic material according to this embodiment will be described.
The cosmetic in the present embodiment can be manufactured by a predetermined procedure depending on the form of the skin cosmetic. For example, the method for producing a cosmetic may include a step of dispersing the component (A) in a dispersion medium containing water to obtain a dispersion liquid, and a step of dissolving or dispersing the component (B) in the dispersion liquid. ..

The form of the obtained cosmetic can be a lotion, a solution, an emulsion, a cream, an ointment, a gel, and the like, and more specifically, an emulsion, a lotion, and a gel.
Further, it is preferable that the cosmetic material forms a film on the skin when applied to the skin.

Since the cosmetic of the present embodiment contains the specific components (A) and (B), it is excellent in the sustained release property of the component (B) after the cosmetic is applied to the skin.
More specifically, in the present embodiment, since the component (B) in the cosmetic material moderately interacts with the component (A), the component (B) is excessively applied immediately after the cosmetic material is applied to the skin. It is possible to suppress transient penetration at a high concentration. Therefore, the action of the cosmetic immediately after being applied to the skin can be made mild and, for example, excessive irritation to the skin can be suppressed. Although the detailed reason for this is unknown, the interaction between the benzene ring of the component (B), which is a hydroxybenzenecarboxylic acid having a specific IOB value or a derivative thereof, and the component (A), which is a cellulose having a specific fiber length. It is considered that this is because the component (B) is trapped.
In addition, in the present embodiment, since the component (B) in the cosmetic material appropriately interacts with the component (A), the component (B) is gradually released from the cosmetic material. Therefore, after applying the cosmetic to the skin, the component (B) can be gradually percutaneously absorbed over a long period of time. Therefore, the durability of the effect of the component (B) in the cosmetic can be obtained.

Moreover, since the cosmetic of this embodiment contains the components (A) and (B), the cosmetic applied to the skin can form a film on the skin. Further, according to the present embodiment, for example, it is possible to obtain a film having excellent abrasion resistance, being resistant to rubbing and scratching, and having a good feeling in use.
More specifically, according to the present embodiment, it is possible to form a film that is water resistant and strong against rubbing, for example, even when the cosmetic is a hydrophilic cosmetic. Therefore, it has excellent resistance to sweating and rubbing of the skin, and the action of the cosmetic on the skin can be maintained for a long time.
Further, by using the cosmetic of the present embodiment, for example, it is possible to form a strong film. For this reason, for example, rubbing of the skin by the collar is reduced, and it is possible to prevent the collar stain, that is, the adhesion of the skin horny layer melanin pigment, so that the collar stain preventing ability can be exhibited.
Further, by using the cosmetic of the present embodiment, for example, sweat generated after applying the cosmetic to the skin can be diffused into the film of the cosmetic. Then, the generated sweat spreads on the film of the cosmetic and wets the film of the cosmetic to increase the surface area of the sweat exposed to the outside air. Therefore, for example, it is possible to make the sweat excellent in quick-drying after sweating. It will be possible. Further, this also makes it possible to suppress body odor.

Next, a method of using the cosmetic will be described.
The method of using the cosmetic according to the present embodiment includes, for example, a step of applying the cosmetic to the skin, and preferably a step of applying the cosmetic to the skin. More specifically, the method of using the cosmetic may include the step of applying the cosmetic to the skin to form a film.
Further, the cosmetic material in the present embodiment may be used for forming a film on the skin.

The embodiments of the present invention have been described above, but these are examples of the present invention, and various configurations other than the above can be adopted.

First, in the following examples, the following materials were used as cellulose.
(Fibrous cellulose)
The following components (A1) to (A5) were used as the unmodified fibrous cellulose.
(A1) BiNFi-s WMa-10002: Microfibrous cellulose, manufactured by Sugino Machine Ltd. (viscosity of 2 mass% dispersion liquid: 3000 mPa·s, average fiber diameter: 30 nm, average fiber length: 1800 nm, average aspect ratio: 60)
(A2) BiNFi-s FMa-1000: microfibrous cellulose, manufactured by Sugino Machine Limited (viscosity of 2% by mass dispersion: 700 mPa·s, average fiber diameter: 20 nm, average fiber length: 550 nm, average aspect ratio: 27. 5)
(A3) BiNFi-s AMa-1000: microfibrous cellulose, manufactured by Sugino Machine Limited (viscosity of 2% by mass dispersion: 2500 mPa·s, average fiber diameter: 30 nm, average fiber length: 550 nm, average aspect ratio: 18. 3)
(A4) BiNFi-s BMa-10002: Microfibrous cellulose, manufactured by Sugino Machine Limited (viscosity of 2% by mass dispersion: 7000 mPa·s, average fiber diameter: 30 nm, average fiber length: 2100 nm, average aspect ratio: 70)
(A5) BiNFi-s IMa-10002: Microfibrous cellulose, manufactured by Sugino Machine Limited (viscosity of 2% by mass dispersion: 7500 mPa·s, average fiber diameter: 40 nm, average fiber length: 2300 nm, average aspect ratio: 57. 5)
(Other cellulose)
As the other cellulose, the following components (A'1) to (A'5) were used.
(A′1) KMN-01: Oxidized cellulose fine fiber, manufactured by Kao Corporation (viscosity of 2% by mass dispersion: 4900 mPa·s, average fiber diameter: 3.3 nm, average fiber length: 830 nm, average aspect ratio: 251. 5, carboxy group content: 1.4 mmol/g, the production method will be described later.)
(A′2) Sunrose SLD-FM: Fine powdery sodium carboxymethyl cellulose, manufactured by Nippon Paper Industries (average particle diameter: 20 μm)
(A′3) CMC Daicel 1190: Water-soluble carboxymethylated cellulose, manufactured by Daicel Finechem Co., Ltd. (viscosity of 2 mass% dispersion liquid: 2980 Pa·s, molecular weight: 680,000, carboxymethyl substitution degree: 3.45 mmol/g)
(A′4) HEC Daicel SE850: Water-soluble hydroxyethyl cellulose, manufactured by Daicel Finechem Co., Ltd. (viscosity of 2 mass% dispersion liquid: 5380 mPa·s, average molecular weight: 1.15 million, degree of etherification: 1.3)
(A′5) Serish FD-100G: Microfibrous cellulose, manufactured by Daicel Finechem Co., Ltd. (viscosity of 2% by mass dispersion: 2800 mPa·s, average fiber length: 0.3 to 0.5 mm)

Further, among the above, the method for producing the oxidized cellulose microfiber (KMN-01) of the component (A′1) is as follows.
(Production of oxidized cellulose microfiber)
Bleached kraft pulp of conifer (Fletcher Challenge Canada, trade name "Machenzie", CSF 650 ml) was used as a natural cellulose fiber. As the TEMPO, a commercially available product (Free radical, 98 mass% manufactured by ALDRICH) was used. A commercially available product (manufactured by Wako Pure Chemical Industries, Ltd.) was used as sodium hypochlorite. A commercially available product (manufactured by Wako Pure Chemical Industries, Ltd.) was used as sodium bromide.
First, 100 g of bleached kraft pulp fiber of softwood was sufficiently stirred with 9900 g of ion-exchanged water, and then TEMPO 1.25% by mass, sodium bromide 12.5% by mass, sodium hypochlorite 28. 4 mass% was added in this order. Using a pH stat, 0.5 M sodium hydroxide was added dropwise to maintain the pH at 10.5, and an oxidation reaction was performed. After the oxidation reaction was carried out for 120 minutes, the dropping was stopped to obtain oxidized pulp. The oxidized pulp was thoroughly washed with ion-exchanged water, and then dehydrated. Then, 3.9 g of oxidized pulp and 296.1 g of ion-exchanged water were stirred for 10 minutes with a mixer (Vita-Mix-Blender ABSOLUTE, manufactured by Osaka Chemical Co., Ltd.). The fiber was refined by the operation to obtain a dispersion liquid of cellulose fine fibers. The solid content concentration of the dispersion was 1.3% by mass. This cellulose fine fiber had an average fiber diameter of 3.3 nm, an average fiber length of 830 nm, an average aspect ratio of 251.5, and a carboxy group content of 1.4 mmol/g.

(Examples 1 to 7, Comparative Examples 1 to 5)
The components shown in Table 1 were mixed at room temperature (25° C., the same applies below) to prepare a skin cosmetic, and the retained amount of the component in the cosmetic was evaluated. The evaluation results are also shown in Table 1.
A dispersion liquid was prepared by dispersing the cellulose of any of the components (A1) to (A5) or (A'1) to (A'3) in water. The component (B) or (B′) was dissolved in the obtained dispersion liquid to obtain a sample. The concentration of each component in the sample is as shown in Table 1.
The obtained sample was filtered through a membrane filter (manufactured by ADVANTEC, DISMIC, PTFE membrane filter 25HPO45AN), and the concentration of the component (B) or (B′) contained in the obtained filtrate was measured. Further, the ratio of the component (B) or (B′) retained in the skin cosmetics of each example was calculated from the obtained quantitative value of the concentration by the following formula.
Retention amount (%) of component (B) or (B′)=(addition amount−quantitative value)/addition amount×100

From Table 1, it can be seen that the skin cosmetics obtained in each example are superior in the retention effect of the component (B) as compared with those in each comparative example.

(Examples 8-10, Comparative Examples 6-11)
The components shown in Table 2 were mixed at room temperature to prepare a skin cosmetic, and the usability of the cosmetic and the permeability of the components in the cosmetic to the skin were evaluated. The evaluation results are also shown in Table 2.
A dispersion liquid was prepared by dispersing the cellulose of any of the components (A1), (A5) or (A'2) to (A'5) in water. Ingredient (B) or (B') was dissolved in the obtained dispersion to obtain a skin cosmetic of each example. The concentration of each component in the cosmetic is as shown in Table 2.

The cosmetics obtained by one professional panelist were applied to the upper arm of a person (40 μL/4 cm ² ), and it was evaluated whether or not the cosmetics could be applied uniformly as the usability when applied to the skin.
In addition, 1 hour or 6 hours after application, after washing the cosmetic on the skin surface with a hot water bath, the component (B) or (B′) that has penetrated into the skin is recovered by the cup shake method (solvent: water). The content of the hydroxybenzenecarboxylic acid derivative contained in the recovered sample solution was quantified by high performance liquid chromatography (HPLC) by the method and conditions described below.
Then, the permeation amount (%) into the skin with respect to the applied amount of the component (B) or (B′) was calculated from the obtained quantitative value. Evaluations were made for the cases where the elapsed time after applying the cosmetic to the skin was 1 hour and 6 hours, respectively.

(HPLC measurement method)
(Measurement condition)
The following conditions were used using a high performance liquid chromatograph with an ultraviolet absorption detector.
Column: L-column ODS 5 μm, 4.6×150 mm (manufactured by Chemical Substance Evaluation Organization)
Column temperature: 40°C
Mobile phase: methanol/5 mmol L ^-1 citric acid (6:4)
Flow rate: 1.0 mL/min
Injection volume: 10 μL
Measurement wavelength: 254 nm
(Quantification method)
For each hydroxybenzenecarboxylic acid used in the examples or comparative examples, a calibration curve was prepared in advance under the above conditions.
Next, for each sample solution collected from the skin surface in each example, HLPC measurement was performed under the above conditions, and the concentration (μg/mL) of the hydroxybenzenecarboxylic acid derivative in the sample solution was determined using a calibration curve. Based on the formula, the hydroxybenzenecarboxylic acid derivative content (g/kg) was calculated.
Hydroxybenzenecarboxylic acid derivative content (g/kg)=C/(25×W)
(In the above formula, C is the concentration (μg/mL) of the hydroxybenzenecarboxylic acid derivative in the sample liquid, and W is the sampled amount (g) of the sample liquid (10 μL).)

From Table 2, the skin cosmetics obtained in each example were uniformly applied to the skin to form a film. Then, in the skin cosmetics obtained in each example, as compared with those in each comparative example, excessive penetration of the component (B) after 1 hour from application of the cosmetic to the skin was suppressed, It can be seen that the component (B) is continuously permeated 6 hours after the application of the ingredient to the skin.

Claims (4)

The following components (A) and (B):
(A) Unmodified fibrous cellulose having an average fiber length of 10 nm or more and less than 0.1 mm,
(B) contains one or more selected from the group consisting of hydroxybenzenecarboxylic acid and salts thereof, hydroxybenzenecarboxylic acid ester and salts thereof, and the component (B) has an IOB value of 0.90 or more 6. A skin cosmetic which is 5 or less. The skin cosmetic according to claim 1, wherein the component (B) contains one or more selected from the group consisting of hydroxybenzenecarboxylic acid esters and salts thereof. The skin cosmetic according to claim 1 or 2, which forms a film on the skin when applied to the skin. A method of using a skin cosmetic, comprising the step of applying the skin cosmetic according to any one of claims 1 to 3 to the skin.