JP2024043278A - Antiperspirant Composition - Google Patents

Abstract

[Problem] To provide an antiperspirant composition that has a good antiperspirant effect and a good texture. [Solution] The antiperspirant composition of the present invention is an antiperspirant composition containing a hydrophobic silica aerogel, a glyceryl alkyl ether, and an antiperspirant component, in which the content of the hydrophobic silica aerogel is 0.1 to less than 1.0 mass%, the content of the glyceryl alkyl ether is 0.1 to 10.0 mass%, and the content of the antiperspirant component is 1.0 to 25.0 mass%. By combining and blending these, a synergistic effect of each component can be achieved to obtain an antiperspirant composition that has a good antiperspirant effect and a good texture. [Selected Figure] None

Description

The present invention relates to antiperspirant compositions. More specifically, the present invention relates to an antiperspirant composition with good antiperspirant action and excellent texture.

Sweat glands are important organs that regulate body temperature by sweating, but the odor generated by sweating causes discomfort. Antiperspirant compositions that contain antiperspirant and antibacterial ingredients and suppress the generation of sweat and odor are used as cosmetics to prevent the discomfort caused by stickiness and odor caused by sweat.
Silica is used in antiperspirant compositions to provide a dry feel when applied. It has been discovered that by blending 1% by mass to 30% by mass of hydrophobic silica aerogel with high oil absorption as the silica to be blended, the hydrophobic silica aerogel effectively absorbs sebum and oils on the skin, improves adhesion to the skin, and enhances the blocking effect of sweat glands, and an antiperspirant composition with improved antiperspirant action has been developed (see, for example, Patent Document 1).
Here, "antiperspirant effect" refers to the effect of suppressing sweat secretion. When the antiperspirant effect is "improved,""good," or "excellent," it means that the secretion of sweat is suppressed.

JP2022-062424A

However, when 1% by mass or more of hydrophobic silica airgel is blended into an antiperspirant composition, the antiperspirant composition tends to thicken, become sticky, difficult to apply, and have a poor texture. On the other hand, when the amount of hydrophobic silica airgel was reduced, the antiperspirant effect tended to decrease. Therefore, an object of the present invention is to provide an antiperspirant composition that has a good antiperspirant effect and has a good texture.
Here, "texture" refers to the feel felt by the user when applying the antiperspirant composition. A "good" texture means that the texture is not sticky, smooth, and has good adhesion to the skin, and is comfortable, while a "poor" texture means that it is sticky, difficult to apply, and has poor adhesion to the skin. It is a bad and unpleasant condition.

The present inventors conducted extensive studies to solve the above problems. As an antiperspirant composition, by combining hydrophobic silica airgel, glyceryl alkyl ether, and antiperspirant components at predetermined contents, the synergistic effect of each component results in a good antiperspirant effect and texture. It has been found that a good antiperspirant composition can be obtained.

That is, the antiperspirant composition of the present invention is an antiperspirant composition containing a hydrophobic silica airgel, a glyceryl alkyl ether, and an antiperspirant component, wherein the content of the hydrophobic silica airgel is 0. 1 to less than 1.0% by mass, the content of the glyceryl alkyl ether is 0.1 to 10.0% by mass, and the content of the antiperspirant component is 1.0 to 25.0% by mass. .
Further, in the antiperspirant composition of the present invention, the hydrophobic silica airgel has a volume-based median diameter of 1 to 200 μm, a specific surface area of 350 to 1000 m ² /g, and a pore volume of 1 It is preferable that the pore radius is ˜6 ml/g and the peak value of the pore radius is 3˜40 nm.
In the antiperspirant composition of the present invention, it is preferable that the hydrophobic silica airgel is spherical.
In the antiperspirant composition of the present invention, the hydrophobic silica airgel preferably has an oil absorption of 400 to 800 mL/100 g and an M value of 20 to 60.
In the antiperspirant composition of the present invention, the glyceryl alkyl ether is preferably ethylhexylglycerin.
In the antiperspirant composition of the present invention, it is preferable that the antiperspirant component is at least one selected from chlorohydroxyaluminum or a complex of chlorohydroxyaluminum/zirconium and glycine.

In the antiperspirant composition of the present invention, the hydrophobic silica airgel with high oil absorption absorbs sebum and carries and sustains the release of the active ingredient glyceryl alkyl ether, and the antiperspirant component acts on the skin from which sebum has been absorbed. It covers the sweat glands and exerts an antiperspirant effect. In addition, the slowly released glyceryl alkyl ether exhibits antibacterial and moisturizing effects, and the synergistic effect of each ingredient is demonstrated, resulting in an antiperspirant effect and texture. can be improved.

The forms shown below are examples of the present invention, and the present invention is not limited to these forms.
The present invention will be explained in detail below.
[Antiperspirant composition]
The antiperspirant composition of the present invention is an antiperspirant composition containing a hydrophobic silica airgel, a glyceryl alkyl ether, and an antiperspirant component, wherein the content of the hydrophobic silica airgel is 0.1 to The content of the glyceryl alkyl ether is 0.1 to 10.0% by mass, and the content of the antiperspirant component is 1.0 to 25.0% by mass.

<Hydrophobic silica airgel>
The hydrophobic silica airgel (hereinafter also simply referred to as "silica airgel") contained in the antiperspirant composition of the present invention may be a known one, for example, one produced by the method described in JP 2018-177620A. can be used.
Preferred properties of the silica airgel used in the present invention will be shown below.

(median diameter)
The silica airgel used in the present invention has a median diameter (hereinafter sometimes simply referred to as "median diameter") in the volume frequency particle size distribution determined by the Coulter Counter method in the range of 1 to 30 μm. When the median diameter of the hydrophobic silica airgel is within this range, it is possible to obtain an antiperspirant composition that does not easily cause white cast and has a smooth texture. Furthermore, from the viewpoint of adhesion to the skin, the particle size of the silica airgel is preferably 30 μm or less. The median diameter is preferably in the range of 1 to 20 μm, particularly preferably 5 to 20 μm.
When the median diameter of the silica airgel is less than 1 μm, the antiperspirant composition tends to thicken and have a poor texture. If the median diameter exceeds 30 μm, clogging may occur when an aerosol type antiperspirant composition is made.

(Specific surface area)
In the present invention, the specific surface area of the silica airgel determined by the BET method (BET specific surface area) is preferably 350 to 1000 m ² /g, more preferably 400 to 850 m ² /g. It is preferable that the BET specific surface area is within this range, since it is possible to provide an antiperspirant composition having an appropriate viscosity and a smooth feel. If the specific surface area is smaller than this range, the effect of improving persistence tends to be small, and if the specific surface area is larger than this range, the antiperspirant composition will thicken and the texture will deteriorate. It tends to get worse.
Here, the specific surface area by the above BET method is determined by drying the sample to be measured at a temperature of 200°C for 3 hours or more under a vacuum of 1 kPa or less, and then applying an adsorption isotherm of only the nitrogen adsorption side at liquid nitrogen temperature. This is the value obtained by acquiring and analyzing it using the BET method.

(Average circularity)
In the present invention, the particle shape of the silica airgel is not particularly limited, but it is preferably spherical, and the average circularity is preferably 0.8 or more, particularly preferably 0.85 or more. As the average circularity becomes larger than 0.8 and approaches 1, each particle becomes closer to a perfect sphere, and the number of aggregated particles decreases. Therefore, if the average circularity is high, rolling properties will be better when used as a cosmetic additive, and an excellent texture will be obtained.
The above-mentioned "average circularity" refers to the following for each particle, using a scanning electron microscope (SEM) to obtain an SEM image with secondary electron detection, low accelerating voltage (1 kV to 3 kV), and 1000x magnification. A value C (circularity) defined by formula (1) is obtained (image analysis), and this circularity C is calculated as an arithmetic average value for 2000 or more particles (image analysis method). At this time, a particle group forming one aggregated particle is counted as one particle.
C=4πS/L ² (1)
In the above formula (1), S represents the area (projected area) that the particle occupies in the image, and L represents the length (perimeter) of the outer periphery of the particle in the image.

(M value)
The silica airgel is hydrophobic. Here, whether or not it is hydrophobic is confirmed by the following method. That is, after putting 25 ml of water into a 50 ml glass sample bottle, adding 0.1 g of silica airgel to be tested and shaking it well, the entire amount of the silica airgel was suspended in the water without being dispersed. You can check by doing it.
The degree of hydrophobicity of the silica airgel can be measured by the M value. The method for measuring the M value is as follows. 0.2 g of silica airgel is added to 50 mL of water in a 250 mL capacity beaker and methanol is slowly added dropwise from the burette. At this time, the solution in the beaker is constantly stirred with a magnetic stirrer. The end point is when the entire amount of the added silica airgel is suspended in the liquid, and the volume percentage (%) of methanol in the liquid mixture in the beaker at the end point is the M value.
The M value, which is an index of hydrophobicity of the silica airgel, is preferably from 20 to 60, preferably from 30 to 50. When the M value is within this range, it becomes possible to impart water repellency to the film formed after application of the antiperspirant composition, improving the antiperspirant effect and causing the film to be washed away by water from the outside. It becomes possible to suppress this.

(silylation)
In the silica airgel exhibiting the above M value, a specific example of a mode in which hydrophobicity is imparted is a mode in which an organic silyl group is introduced to the surface by being treated with a silylating agent. The organic silyl group is preferably a trimethylsilyl group because it tends to have an M value within the above-mentioned range.
Specific examples of the above-mentioned silylating agents include chlorosilanes such as chlorotrimethylsilane, dichlorodimethylsilane, and trichloromethylsilane, alkoxysilanes such as monomethyltrimethoxysilane and monomethyltriethoxysilane, hexamethyldisilazane, and hexamethylcyclotriethoxysilane. Silazane such as silazane, siloxane such as hexamethylsiloxane, octamethyltrisiloxane, cyclic siloxane such as siloxane octamethylcyclotetrasilazane, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, etc. It will be done. Among them, chlorotrimethylsilane, dichlorodimethylsilane, trichloromethylsilane, octamethylcyclotetrasiloxane, hexamethyldisilazane, and hexamethyldisiloxane are particularly preferred since the M value can be easily controlled within the above range. Generally, the silylating agent and the silanol groups of the silica airgel react to introduce corresponding hydrophobic groups onto the surface of the silica airgel.

(pore volume)
The silica airgel used in the present invention preferably has a pore volume of 3 to 6 mL/g. The lower limit is more preferably 3.5 mL/g or more, particularly 4 mL/g or more. Moreover, it is more preferable that the upper limit is 6 mL/g or less. It is preferable that the pore volume is within this range because it exhibits an excellent effect of supporting antibacterial components. When the pore volume is smaller than this range, the voids become smaller and the amount of antibacterial component supported tends to become smaller. If the pore volume is larger than this range, the antiperspirant composition tends to thicken and have a poor texture.
The pore volume was determined by obtaining an adsorption isotherm in the same manner as in the BET specific surface area measurement described above, and using the BJH method (Barrett, E.P.; Joyner, L.G.; Halenda, P.P., J.D.). Am. Chem. Soc. 73, 373 (1951) (hereinafter sometimes referred to as "BJH pore volume").The pores measured by this method have a radius of 1 The pores are 100 nm in diameter, and the integrated value of the pore volumes in this range is the pore volume in the present invention.

(Peak and distribution of pore radius)
It is recommended that the silica airgel used in the present invention has a peak pore radius of preferably 10 to 40 nm, more preferably 10 to 30 nm. Since the peak of the pore radius exists sharply in this range, the transparency of the silica airgel tends to be high, and when it is applied to the skin as an antiperspirant composition, it is less likely to cause a white cast.
In the present invention, the peak and distribution of the pore radius are determined by the cumulative pore volume (volume) obtained by analyzing the adsorption isotherm on the adsorption side obtained in the same manner as above using the BJH method. distribution curve).

(Oil absorption amount)
As mentioned above, the silica airgel used in the present invention preferably has a large specific surface area and a large pore volume, and its oil absorption is usually preferably 400 mL/100 g or more and 800 mL/100 g or less. It is preferable that the oil absorption amount is within this range, since it is possible to provide a cosmetic with good appearance retention and smooth texture. If the lower limit of the oil absorption amount is smaller than this range, the amount of antibacterial component supported tends to be small. If the upper limit of the oil absorption amount exceeds this range, the antiperspirant composition tends to thicken and its texture deteriorates.
The oil absorption amount is a value measured by the method described in JIS K5101-13-1 "Refined linseed oil method".

<Glyceryl alkyl ether (antibacterial ingredient)>
Glyceryl alkyl ether has an antibacterial effect, and by adding it to an antiperspirant composition, it suppresses the growth of resident bacteria on the skin that produce substances that cause body odor, thereby providing a deodorizing effect. In addition, since it is a glycerin derivative, it has a moisturizing effect, prevents dryness due to oil absorption of silica airgel, and has the effect of improving texture by moderately moisturizing.

Examples of the glyceryl alkyl ether that can be used in the present invention include methylheptylglycerin, ethylhexylglycerin, 1-octylglyceryl ether, isodecylglyceryl ether, and dodecylglycerin, among which ethylhexylglycerin is preferred. One type of glyceryl alkyl ether may be used alone, or two or more types may be used in an appropriate combination.

<Antiperspirant ingredient>
The antiperspirant component is not particularly limited as long as it suppresses the generation of sweat by astringent the skin, and any general-purpose component can be used. For example, chlorohydroxy aluminum, aluminum chloride, allantoin aluminum salt, chlorohydroxy zirconium, zirconium oxide, tannic acid, aluminum potassium sulfate, aluminum zirconium trichlorohydrate, aluminum zirconium tetrachlorohydrate, aluminum zirconium pentachlorohydrate, aluminum zirconium octa Examples include chlorohydrate, aluminum zirconium tetrachlorohydrex glycine, zinc oxide, zinc paraphenolsulfonate, and baked alum. These may be used alone or in combination of two or more. In particular, it is preferably at least one selected from chlorohydroxyaluminum or aluminum-zirconium tetrachlorohydrexglycine.

<Content of each component>
In the antiperspirant composition of the present invention, the amount of silica airgel blended is 0.1 to less than 1.0% by mass, and 0.3 to 0.8% by mass, based on 100% by mass of the entire antiperspirant composition. % is preferable. The larger the amount, the better the antiperspirant effect, but if the amount is 1.0% by mass or more, it tends to become sticky and difficult to apply, and the texture tends to deteriorate.
Further, the content of glyceryl alkyl ether is 0.1 to 10.0% by mass, preferably 0.5% to 2.0% by mass, from the viewpoint of deodorizing effect. If the content is less than 0.1% by mass, the deodorizing effect may be insufficient.
Further, the content of the antiperspirant component is 1.0 to 25.0% by mass, preferably 2.0% to 20.0% by mass, from the viewpoint of antiperspirant effect and skin irritation. If the content is less than 1.0% by mass, the antiperspirant effect may be insufficient.
When the content of each component is within the above range, the hydrophobic silica airgel with high oil absorption absorbs sebum and carries and sustainably releases the active ingredient glyceryl alkyl ether, and the antiperspirant component absorbs sebum. It covers the sweat glands of the skin and exerts an antiperspirant effect. In addition, the slowly released glyceryl alkyl ether exhibits antibacterial and moisturizing effects, and the synergistic effect of each ingredient is demonstrated, resulting in an excellent antiperspirant effect. Sweat effect and texture can be obtained.

<Other ingredients>
In the antiperspirant composition of the present invention, components known as components of antiperspirant compositions can be contained without particular limitation depending on the purpose and use of the antiperspirant composition. For example, surfactants, antioxidants, emulsion stabilizers, pH adjusters, astringents, preservatives, ultraviolet absorbers, chelating agents, humectants, thickeners, cooling agents, anti-inflammatory agents, vitamins, anti-caking agents. and feel-improving agents. These may be used alone or in combination of two or more. The content of the other components in the antiperspirant is not particularly limited and can be appropriately selected depending on the purpose.

Examples of the surfactant include nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, and specifically, polyoxyethylene polyoxypropylene glycol, polyoxypropylene glycol, Examples include oxyethylene lauryl ether, polyvinyl alcohol, polyethylene glycol monooleate, polyethylene glycol monostearate, polyoxyethylene sorbitan monostearate, sorbitan monopalmitate, sorbitan monolaurate, and sorbitan stearate. These may be used alone or in combination of two or more.

The antioxidant is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include ascorbic acid, alkali metal salts of ascorbic acid, butylated hydroxyanisole, tocotrienols, and the like. These may be used alone or in combination of two or more.

The astringent is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include zinc sulfate, zinc phenolsulfonate, citric acid, tartaric acid, lactic acid, tannic acid, alum, and the like. These may be used alone or in combination of two or more.

The preservative is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include salicylic acid, sulfur, resorcinol, phenoxyethanol, propylparapeben, and the like. These may be used alone or in combination of two or more.

The humectant is not particularly limited and can be selected as appropriate depending on the purpose, for example, glycerin, 1,3-butylene glycol, propylene glycol, diglycerin, polyglycerin, diethylene glycol, polyethylene glycol, ethylene glycol monomer. Examples include ethyl ether, sorbitol, dextrin, alkyl benzoate (C12-15), dimethicone, and cyclopentasiloxane. These may be used alone or in combination of two or more.

The thickener is not particularly limited and can be appropriately selected depending on the purpose, for example, sodium polyacrylate, cellulose ether, sodium alginate, ozokerite, stearyl dimethicone, (C20-40) alcohol, stearyl alcohol. etc. etc. These may be used alone or in combination of two or more.

The anti-caking agent is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include sericite and talc. These may be used alone or in combination of two types.

The feel improving agent is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include sericite and talc. These may be used alone or in combination of two types.

[Dosage form of antiperspirant composition]
The antiperspirant composition of the present invention may be in the form of, for example, an antiperspirant powder, an antiperspirant stick, an antiperspirant deodorant spray, an antiperspirant lotion, a roll-on antiperspirant, and the like.

[Method for producing antiperspirant composition]
The antiperspirant composition of the present invention can be manufactured according to a known method. For example, the silica airgel and glyceryl alkyl ether are blended to a desired content to prepare an active ingredient-supported silica airgel. An antiperspirant composition can be produced by blending the antiperspirant component and other components therein.

EXAMPLES Hereinafter, Examples will be shown to specifically explain the present invention, but the present invention is not limited to these Examples.

<Silica aerogel>
The hydrophobic silica aerogel has a surface modified with a trimethylsilyl group and was produced by the method described in JP 2018-177620 A. The physical properties of the silica aerogel used in the examples are shown in Table 1.

<Evaluation method>
The physical properties of the silica aerogel were evaluated by the following methods.

(Measurement of average circularity)
More than 2000 silica particles were observed at a magnification of 1000 times using an SEM (S-5500 manufactured by Hitachi High-Technologies Corporation, accelerating voltage 3.0 kV, secondary electron detection), and the SEM images were analyzed, and the average circularity was calculated according to the above definition.

(Measurement of particle size distribution and median diameter by Coulter counter method)
0.3 g of silica was added to 40 ml of ethanol and dispersed for 5 minutes at an output of 100 W using an ultrasonic cleaner UT-105S manufactured by Sharp Manufacturing Co., Ltd. The above-mentioned dispersion was carried out using a 50 ml laboratory screw tube bottle, which was placed in a washing tank containing an appropriate amount of water.

The obtained ethanol dispersion was measured using a precision particle size distribution measuring device, Multisizer 3, manufactured by Beckman Coulter, Inc., with a 100 μm aperture tube.
From the obtained particle size distribution, the median diameter for the volume distribution was evaluated.

(Measurement of other physical property values)
The BET specific surface area and BJH pore volume were measured using BELSORP-max manufactured by Bell Japan Co., Ltd. according to the above definitions. The oil absorption was measured by the "refined linseed oil method" specified in JIS K5101-13-1.

(Example 1, Comparative Examples 1-2)
An antiperspirant composition was prepared according to the formulation in Table 2. The manufacturing procedure is shown below.
(1) Mix component A, component B, and component D, respectively.
(2) While adding component B to component A, stir and mix.
(3) Stir and mix while adding component C to 2.
(4) Stir and mix while adding component D to 3.
(5) 4 is poured into a stick-shaped container with a height of 750 mm and an oval shape of 370 mm x 170 mm, and is cooled for 30 minutes to form a stick shape.

<Sensory test of antiperspirant composition>
A sensory test was conducted by 20 expert panelists regarding the antiperspirant effect of the antiperspirant compositions produced according to the Examples and Comparative Examples. Each antiperspirant composition was applied to the armpits each day after evening bath and kept in cool and ventilated conditions. Each evaluation item was evaluated in five stages according to the criteria shown in Table 3. The average value was determined and evaluated according to the following criteria. The results are shown in Table 4.

The evaluation items are shown below.
・Evaluation on the first day of use ・Evaluation after 1 hour of exercise that causes sweating on a different day from other evaluations ・Evaluation after 7 days of use ・Product texture

The above "evaluation on the first day of use" refers to the evaluation of the antiperspirant effect in the evening after one day after first applying the antiperspirant composition. This is an evaluation of the antiperspirant effect on the 7th day when the antiperspirant composition was removed and the application of the antiperspirant composition to the armpit after bathing was continued for the 7th day.

The above-mentioned "product texture" includes smoothness (does the antiperspirant composition slide easily and does not get caught on the skin), non-stickiness (does it have a sticky feel), and ease of application (does it feel silky and easy to apply to the skin?) The adhesion to the skin (no adhesion to clothes etc. after application) was evaluated. The evaluation criteria are shown below.

The judgment criteria are shown below.
(Judgment): (Average value of evaluation)
◎ (Very good): 4.5 or more 〇 (Good): 3.5 or more and less than 4.5 △ (Insufficient): 2.5 or more and less than 3.5 × (Poor): Less than 2.5
The results are shown in Table 4.

From the results in Table 4, the antiperspirant composition of the present invention, which is an example, has a smaller amount of silica airgel than Comparative Example 1, which has a larger amount of silica airgel. Thickening is suppressed and the texture of the product is excellent.
Compared to Comparative Example 2 in which silica airgel is not blended, since silica airgel is blended, a synergistic effect of each component is exhibited, and the antiperspirant effect is excellent.
Therefore, it can be seen that Example 1 had a better antiperspirant effect and texture than those of the comparative examples.

Claims (6)

An antiperspirant composition containing a hydrophobic silica airgel, a glyceryl alkyl ether, and an antiperspirant component,
The content of the hydrophobic silica airgel is 0.1 to less than 1.0% by mass,
The content of the glyceryl alkyl ether is 0.1 to 10.0% by mass,
An antiperspirant composition characterized in that the content of the antiperspirant component is 1.0 to 25.0% by mass. The hydrophobic silica airgel has a volume-based median diameter of 1 to 200 μm, a specific surface area of 350 to 1000 m ² /g, a pore volume of 1 to 6 ml/g, and a peak value of pore radius measured by the Coulter counter method. The antiperspirant composition according to claim 1, which has a particle diameter of 3 to 40 nm. The antiperspirant composition according to claim 1 or 2, wherein the hydrophobic silica airgel is spherical. The antiperspirant composition according to claim 1 or 2, wherein the hydrophobic silica airgel has an oil absorption of 400 to 800 mL/100 g and an M value of 20 to 60. The antiperspirant composition according to claim 1 or 2, wherein the glyceryl alkyl ether is ethylhexylglycerin. The antiperspirant composition according to claim 1 or 2, wherein the antiperspirant component is at least one selected from chlorohydroxyaluminum and a complex of chlorohydroxyaluminum zirconium and glycine.