JP7498474B2 - Shaving composition - Google Patents

Description

The present invention relates to a shaving agent composition.

Shaving agents are commonly used when shaving beards or body hair. Traditionally, fatty acid soaps, which have excellent foaming power and foam quality, have been widely used as shaving agents. However, shaving agents based on fatty acid soaps are alkaline. For this reason, the above shaving agents have problems such as being highly irritating to the skin, which is naturally weakly acidic, and leaving a tingling or tight feeling after rinsing.

In view of the above problems, it has been proposed to use non-soap anionic surfactants instead of fatty acid soaps. Patent documents 1 to 3 and Patent document 4 propose phosphate ester surfactants and amino acid surfactants, respectively, as anionic surfactants to replace fatty acid soaps. In addition, although not a shaving agent, a low-irritation cleaning agent composition has been proposed that combines an acylalkyl taurine salt type anionic surfactant with an amphoteric surfactant (Patent documents 5 and 6).

In addition, non-foaming gel-type shaving agents that are not based on surfactants have been proposed to improve the smoothness of the razor (Patent Documents 7 to 9). Also, a shaving agent that contains an anionic surfactant, an amphoteric surfactant, and a water-soluble polysaccharide has been proposed, focusing on functions other than shaving (cleaning function) (Patent Document 10).

Patent No. 2799777 Japanese Patent Application Laid-Open No. 7-316031 Japanese Patent Application Laid-Open No. 7-316547 JP 2018-131542 A Patent No. 4830305 Patent No. 3178085 Japanese Patent Application Laid-Open No. 9-132516 Patent No. 4148546 JP 2005-206464 A JP 2006-96754 A

Conventional shaving agents containing anionic surfactants are still insufficient in reducing skin irritation. In addition, shaving agents, particularly for use in hair salons, medical facilities, and other professional settings, are required to have foaming power that can quickly create a voluminous lather (hereinafter referred to as "good foaming power"), as well as foaming properties that can create a dense lather that is easy to shave beard and body hair (hereinafter referred to as "good foaming properties"). Furthermore, in addition to the shaving function, there is a demand for functions other than simple cleaning, such as a skin cleansing function that keeps the skin in good condition even when used repeatedly on a daily basis.

The present invention aims to provide a shaving agent composition that contains an anionic surfactant, yet achieves further reduction in skin irritation, has good foaming power and good foaming properties, and also has a skin cleansing function.

The present invention relates to
The composition comprises a nonionic surfactant (A), an anionic surfactant (B), and a cellulose derivative (C),
The total content of (A) and (B) is 5.0 to 30.0 mass %,
The ratio (by mass) of the content of (A) to the content of (B) is 1/3 or more,
A shaving composition characterized by being weakly acidic;
I will provide a.

According to the present invention, a shaving agent composition is achieved that contains an anionic surfactant, yet is less irritating to the skin, has good foaming power and good foaming properties, and also has a skin cleansing function.

The shaving composition of the present invention contains a nonionic surfactant (A), an anionic surfactant (B), and a cellulose derivative (C).

The total content of the nonionic surfactant (A) and the anionic surfactant (B) is 5.0 to 30.0% by mass. If the total is less than 5.0% by mass, the foaming power and skin cleansing function are insufficient, and it is difficult to achieve good foaming. If the total exceeds 30.0% by mass, irritation to the skin increases and it is difficult to achieve the skin cleansing function. The lower limit of the total may be 6.0% by mass or more, 7.0% by mass or more, 8.0% by mass or more, 9.0% by mass or more, 10.0% by mass or more, or even 11.0% by mass or more. The upper limit of the total may be 27.5% by mass or less, 25.0% by mass or less, 22.5% by mass or less, 20.0% by mass or less, 18.0% by mass or less, or even 15.0% by mass or less.

The ratio C _A /C _B (mass basis) of the content C _A of the nonionic surfactant (A) to the content C _B of the anionic surfactant (B) is 1/3 or more. If the ratio C _A /C _B is less than 1/3, it is difficult to further reduce the irritation to the skin even if the composition is weakly acidic. In addition, it is difficult to achieve the skin cleansing function. The ratio C _A /C _B may be 1/2.75 or more, 1/2.5 or more, or even 1/2.25 or more. The upper limit of the ratio C _A /C _B is preferably 4 or less, and may be 3 or less, 2 or less, 1.5 or less, 1 or less, 1/1.33 or less, or even 1/1.5 or less. Anionic surfactants usually have a higher foaming power than nonionic surfactants. If the ratio C _A /C _B becomes excessively large, the foaming power tends to decrease. In addition, the composition is likely to feel sticky after use.

The composition of the present invention is weakly acidic. The pH of the composition of the present invention is less than 7.0, and may be 6.9 or less, or even 6.8 or less. If the pH is 7.0 or more, particularly if it exceeds 7.0 (becoming alkaline), the cleaning power and foaming power are improved, but it becomes difficult to further reduce irritation to the skin and achieve the skin cleansing function. The lower limit of the pH is preferably 3.0 or more, and may be 4.0 or more, 5.0 or more, 5.5 or more, or even 6.0 or more. If the pH is too low, the foaming power and the quality of the foaming property tend to decrease. In addition, the stability of the composition tends to decrease.

An example of the nonionic surfactant (A) is at least one selected from polyglycerin-based surfactants and sugar-based surfactants. However, the nonionic surfactant (A) is not limited to the above examples. The nonionic surfactant (A) may be at least one selected from polyglycerin fatty acid esters, polyglycerin alkyl ethers, and alkyl glucosides. In this case, good foaming power and skin cleansing function are more reliably achieved.

Polyglycerol fatty acid ester is a type of polyglycerol surfactant. The average degree of polymerization of polyglycerol constituting the polyglycerol fatty acid ester is not particularly limited, and may be 2 to 20, or 6 to 10. The fatty acid constituting the polyglycerol fatty acid ester is not particularly limited. The number of carbon atoms of the fatty acid constituting the polyglycerol fatty acid ester may be 6 to 30, or 8 to 22. The fatty acid constituting the polyglycerol fatty acid ester may be a saturated fatty acid or an unsaturated fatty acid. Examples of polyglycerol fatty acid ester are decaglyceryl laurate (polyglyceryl-10 laurate), decaglyceryl stearate, decaglyceryl isostearate, decaglyceryl oleate, pentaglyceryl laurate, pentaglyceryl stearate, pentaglyceryl isostearate, pentaglyceryl oleate, octaglyceryl laurate, octaglyceryl myristate, pentaglyceryl myristate, and decaglyceryl myristate.

Polyglycerol alkyl ether is a type of polyglycerol-based surfactant. The average degree of polymerization of the polyglycerol constituting the polyglycerol alkyl ether is not particularly limited, and may be 2 to 100, or 4 to 40. The number of carbon atoms in the alkyl group is not particularly limited. The number of carbon atoms in the alkyl group may be 6 to 30, or 8 to 22. The alkyl group may be linear or branched. Examples of polyglycerol alkyl ethers include diglycerol monooctyl ether, diglycerol monodecyl ether, diglycerol monododecyl ether, diglycerol monotetradecyl ether, triglycerol monooctyl ether, triglycerol monodecyl ether, triglycerol monododecyl ether, triglycerol monotetradecyl ether, tetraglycerol monooctyl ether, tetraglycerol monodecyl ether, tetraglycerol monododecyl ether, tetraglycerol monotetradecyl ether, hexaglycerol monooctyl ether, hexaglycerol monodecyl ether, hexaglycerol monotetradecyl ether, hexaglycerol mono dodecyl ether, hexaglycerin monotetradecyl ether, octaglycerin monooctyl ether, octaglycerin monodecyl ether, octaglycerin monododecyl ether, octaglycerin monotetradecyl ether, decaglycerin monooctyl ether, decaglycerin monodecyl ether, decaglycerin monododecyl ether, decaglycerin monotetradecyl ether, eicosaglycerin monooctyl ether, eicosaglycerin monodecyl ether, eicosaglycerin monododecyl ether (polyglyceryl-20 lauryl ether), and eicosaglycerin monotetradecyl ether.

Alkyl glucoside is a type of sugar-based surfactant. The number of carbon atoms in the alkyl group constituting the alkyl glucoside is not particularly limited, and may be 6 to 30, or 8 to 22. Examples of alkyl glucoside are lauryl glucoside, capryl glucoside, (caprylyl/capryl) glucoside, myristyl glucoside, decyl glucoside, cetostearyl glucoside, octyl glucoside, nonyl glucoside, and coconut oil alkyl glucoside.

The composition of the present invention may contain two or more types of nonionic surfactants (A).

The content of the nonionic surfactant (A) is, for example, 1.5 to 20.0% by mass. The upper limit of the content may be 15.0% by mass or less, 12.0% by mass or less, 10.0% by mass or less, or even 8.0% by mass or less. The lower limit of the content may be 2.0% by mass or more, 2.5% by mass or more, or even 3.0% by mass or more. If the content of the nonionic surfactant (A) is excessively large, the product is likely to feel sticky after use.

An example of the anionic surfactant (B) is a carboxylic acid surfactant. However, the anionic surfactant (B) is not limited to the above examples. Among anionic surfactants, carboxylic acid surfactants are less irritating to the skin.

Examples of carboxylic acid surfactants are N-acylamino acid salts, N-acyl-N-alkylamino acid salts, alkyl ether carboxylates, and hydroxyalkyl ether carboxylates. Examples of salts are sodium salts, potassium salts, monoethanolamine salts, diethanolamine salts, triethanolamine salts, and ammonium salts. Examples of amino acids constituting N-acylamino acid salts are glutamic acid, glycine, aspartic acid, and alanine. Examples of amino acids constituting N-acyl-N-alkylamino acid are glutamic acid, glycine, and alanine. Examples of acyl groups constituting N-acylamino acid salts and N-acyl-N-alkylamino acid salts are lauroyl, myristoyl, palmitoyl, and coconut oil fatty acid groups. Examples of alkyl groups constituting N-acyl-N-alkylamino acid are methyl, ethyl, propyl, and isopropyl groups. Examples of N-acylamino acid salts are sodium, potassium and triethanolamine salts of cocoyl glycine, lauroyl glutamic acid, myristoyl glutamic acid and cocoyl glutamic acid. Examples of N-acyl-N-alkylamino acid salts are sodium, potassium and triethanolamine salts of lauroyl isopropyl glycine, lauroyl sarcosine, myristoyl sarcosine, palmitoyl sarcosine and lauroyl methylalanine. Examples of alkyl ether carboxylates are polyoxyethylene lauryl ether carboxylates (e.g. laureth-4 acetate) and sodium and potassium salts of trideceth carboxylate. Examples of hydroxyalkyl ether carboxylates are sodium and potassium salts of lauryl glycol carboxylate and tridecyl glycol carboxylate.

The composition of the present invention may contain a hydroxyalkyl ether carboxylate as the anionic surfactant (B).

The composition of the present invention may contain two or more types of anionic surfactants (B). The composition of the present invention may contain, as the two or more types of anionic surfactants (B), a hydroxyalkyl ether carboxylate and at least one selected from an N-acyl amino acid salt, an N-acyl-N-alkyl amino acid salt, and an alkyl ether carboxylate, or may contain a hydroxyalkyl ether carboxylate and an N-acyl amino acid salt.

Fatty acid soap may be excluded from the anionic surfactant (B). Fatty acid soap is formed by neutralizing a fatty acid with an alkali, and is usually alkaline. When a fatty acid soap is included as the anionic surfactant (B), it tends to be difficult to make the composition weakly acidic.

The content of the anionic surfactant (B) is, for example, 4.0 to 25.0% by mass. The upper limit of the content may be 20.0% by mass or less, 15.0% by mass or less, 12.0% by mass or less, or even 10.0% by mass or less. The lower limit of the content may be 5.0% by mass or more, 6.0% by mass or more, or even 7.0% by mass or more. If the content of the anionic surfactant (B) is excessively large, irritation to the skin tends to increase.

An example of the cellulose derivative (C) is at least one selected from alkyl cellulose, hydroxyalkyl cellulose, hydroxyalkyl alkyl cellulose, and carboxyalkyl cellulose. The number of carbon atoms of the alkyl group constituting the cellulose derivative (C) may be 1 to 5 or 1 to 3. Examples of alkyl cellulose are methyl cellulose and ethyl cellulose. Examples of hydroxyalkyl cellulose are hydroxymethyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose. An example of hydroxyalkyl alkyl cellulose is hydroxypropyl methyl cellulose. An example of carboxyalkyl cellulose is carboxymethyl cellulose. The cellulose derivative (C) is preferably hydroxyalkyl alkyl cellulose, and more preferably hydroxypropyl methyl cellulose. In this case, good foaming properties can be more reliably achieved.

The cellulose derivative (C) may be water-soluble and dissolve in water at room temperature (25°C).

The weight average molecular weight (Mw) of the cellulose derivative (C) is, for example, 50,000 to 500,000, and may be 100,000 to 450,000, or even 200,000 to 400,000. When Mw is within these ranges, good foaming power and good foaming properties are more reliably achieved. Mw can be evaluated, for example, by gel permeation chromatography (GPC).

The composition of the present invention may contain two or more types of cellulose derivatives (C).

The content of the cellulose derivative (C) is, for example, 0.5 to 5.0% by mass. The upper limit of the content may be 4.0% by mass or less, 3.0% by mass or less, 2.5% by mass or less, 2.0% by mass or less, or even 1.5% by mass or less. The lower limit of the content may be 0.6% by mass or more, 0.75% by mass or more, or even 0.8% by mass or more. If the content of the cellulose derivative (C) is excessively small, the quality of the foaming property tends to decrease. If the content of the cellulose derivative (C) is excessively large, the viscosity of the composition tends to increase, and the foaming power tends to decrease.

The composition of the present invention usually contains water. The main component other than the nonionic surfactant (A), the anionic surfactant (B), and the cellulose derivative (C) may be water. The main component means the component with the largest content. The content of the main component is, for example, 50% by mass or more, and may be 70% by mass or more, 80% by mass or more, 90% by mass or more, 95% by mass or more, or even 99% by mass or more.

The composition of the present invention may contain other components other than the nonionic surfactant (A), the anionic surfactant (B), and the cellulose derivative (C). The other components are preferably components commonly used in cosmetics, quasi-drugs, pharmaceuticals, etc. Examples of the other components are surfactants other than (A) and (B), as well as additives such as polyhydric alcohols, higher alcohols, cationic polymers, preservatives, chelating agents, pH adjusters, moisturizers, humectants, antibacterial and germicidal agents, anti-inflammatory agents, vitamins, amino acids, viscosity adjusters, cooling agents, warming agents, colorants, and fragrances. However, the other components and additives are not limited to the above examples. The composition of the present invention may contain two or more other components. When the composition contains other components, the total content thereof may be, for example, 5.0% by mass or less, 4.0% by mass or less, or even 3.0% by mass or less.

The composition of the present invention may or may not substantially contain cationic surfactants and/or amphoteric surfactants. For example, if an amphoteric surfactant is contained, the composition may tend to be less stable or to feel sticky after use. In this specification, "substantially free" means that the content is, for example, less than 0.5% by mass, preferably 0.3% by mass or less, and more preferably 0.1% by mass or less.

The composition of the present invention may be in the form of, for example, a solution, cream, emulsion, or gel. However, the dosage form is not limited to the above examples. The composition of the present invention can be made into each dosage form by known methods.

The composition of the present invention is a foamable composition that can be foamed using hands, a shaving brush, a lather mixer, or the like. The composition of the present invention can be used, for example, by foaming (lathering) and then applying it to the area of the body of a human or non-human animal that is to be shaved. The foaming and/or shaving may be performed by a barber or the like. The subject of shaving is typically beard and body hair on the legs, armpits, etc. The composition can also be used for face washing and body washing. However, the method of using the composition of the present invention is not limited to the above examples.

The composition of the present invention can be produced by a conventional method of mixing the components in the prescribed amounts.

The present invention will be described in more detail below with reference to examples. The present invention is not limited to the following examples.

[Preparation of Composition]
Shaving compositions having the compositions shown in Tables 1 to 3 below were prepared by mixing each material with purified water. The content of each component shown in the tables is in mass %, and the ratio C _A /C _B is based on mass. The compositions were in the form of a solution. The pH of each of the prepared compositions was adjusted to 6.5 by adding a pH adjuster.

[evaluation]
The prepared compositions were evaluated as follows.

(Lather, density of foam, ease of shaving, no irritation on skin)
Twenty expert evaluators used a wet shaving brush to lather the composition and shaved their beards with the resulting lather, and evaluated lathering (whether a voluminous lather was quickly obtained), lather density (whether a dense lather with a bouncy feel was obtained), ease of shaving, and lack of tingling sensation on the skin during shaving. Lathering corresponds to foaming power, lather density and ease of shaving correspond to foaming quality, and lack of tingling sensation corresponds to skin irritation. Evaluation was made on a five-point scale of 5 points (very good), 4 points (good), 3 points (average), 2 points (not very good), and 1 point (bad), and for each evaluation item, an average of 4.0 points or more by the 20 evaluators was rated as ◎ (excellent), 3.0 points or more but less than 4.0 points was ◯ (good), 2.0 points or more but less than 3.0 points was △ (passable), and less than 2.0 points was × (unacceptable).

(No tightness on the skin, smooth skin)
Twenty expert evaluators gently washed their faces, then used wet hands to lather the composition, and washed their faces with the resulting foam. After thoroughly rinsing off the foam, they gently wiped off the water with a towel, and evaluated the skin for its lack of tightness and smoothness. The lack of tightness corresponds to skin irritation, and the smoothness corresponds to skin cleansing function. The evaluation was carried out in the same manner as above, with the grades of ◎, ◯, △, and ×.

As shown in Tables 1 to 3, in each Example, the skin was free from stinging, the skin was free from tightness, and the skin was smooth, improved compared to Comparative Example 1, in which the ratio C _A /C _B was less than 1/3. It was confirmed that the control of the ratio C _A /C _B achieved further reduction in skin irritation and skin cleansing function. In addition, in each Example, the foaming, foam density, and skin smoothness were improved compared to Comparative Example 2, which did not contain anionic surfactant (B). The foam density, shaving ease, and skin free from stinging were improved compared to Comparative Example 3, which did not contain cellulose derivative (C). The skin smoothness was improved compared to Comparative Example 4, which did not contain cellulose derivative (C) and contained a polysaccharide-based polymer.

Separately from the above, a composition of Comparative Example 5 was prepared, which contains the same components and amounts of nonionic surfactant (A), anionic surfactant (B) and cellulose derivative (C) as in Example 1, but is weakly alkaline (pH = 7.5) by adjusting the amount of pH adjuster added. When the composition was evaluated as described above, the skin was rated x (not good) for lack of stinging sensation, lack of tightness, and smoothness. A composition of Comparative Example 6 was prepared, which contains the same components and amounts of nonionic surfactant (A), anionic surfactant (B) and cellulose derivative (C) as in Example 1, but is acidic (pH = 2.5) by adjusting the amount of pH adjuster added. When the composition was evaluated as described above, the foaming, foam density, and ease of shaving were rated x (not good).

The shaving composition of the present invention can be used, for example, for shaving beard and body hair, and can also be used for daily face and body washing.

Claims (4)

The composition comprises a nonionic surfactant (A), an anionic surfactant (B), a cellulose derivative (C), and water ,
The total content of (A) and (B) is 5.0 to 30.0 mass %,
The ratio (by mass) of the content of (A) to the content of (B) is 1/3 or more and 3 or less ,
The (A) is at least one selected from the group consisting of polyglycerol fatty acid esters, polyglycerol alkyl ethers, and alkyl glucosides,
The content of the (A) is 2.0 to 12.0 mass %,
The (B) contains a carboxylic acid surfactant,
the carboxylic acid surfactant is at least one selected from the group consisting of N-acylamino acid salts, N-acyl-N-alkylamino acid salts, alkyl ether carboxylates, and hydroxyalkyl ether carboxylates;
The (B) does not contain fatty acid soaps,
The content of the (B) is 4.0 to 20.0 mass %,
The (C) is at least one selected from alkyl cellulose, hydroxyalkyl cellulose, hydroxyalkyl alkyl cellulose, and carboxyalkyl cellulose,
The content of the (C) is 0.5 to 3.0 mass %,
It is weakly acidic,
Shaving compositions other than those containing ultramarines. The shaving composition according to claim 1 , wherein (C) is hydroxypropyl methylcellulose. The shaving composition according to claim 1 or 2 , wherein the content of (C) is 0.5 to 5% by mass. The composition comprises a nonionic surfactant (A), an anionic surfactant (B), a cellulose derivative (C), and water ,
The total content of (A) and (B) is 5.0 to 30.0 mass %,
The ratio (by mass) of the content of (A) to the content of (B) is 1/3 or more and 3 or less ,
The (A) is at least one selected from the group consisting of polyglycerol fatty acid esters, polyglycerol alkyl ethers, and alkyl glucosides,
The content of the (A) is 2.0 to 12.0 mass %,
The (B) contains a carboxylic acid surfactant,
the carboxylic acid surfactant is at least one selected from the group consisting of N-acylamino acid salts, N-acyl-N-alkylamino acid salts, alkyl ether carboxylates, and hydroxyalkyl ether carboxylates;
The (B) excludes fatty acid soaps and sodium polyoxyethylene myristyl ether sulfate,
The content of the (B) is 4.0 to 20.0 mass %,
The (C) is at least one selected from alkyl cellulose, hydroxyalkyl cellulose, hydroxyalkyl alkyl cellulose, and carboxyalkyl cellulose,
The content of the (C) is 0.5 to 3.0 mass %,
A shaving composition characterized by being weakly acidic.