JP2001213759A - Skin cleaning agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a skin cleaning agent excellent in foamability, foam holding, detergency, and high in safety to the skin and improved in refreshed finishment. SOLUTION: This skin cleaning agent contains (A) a fatty acid isopropanol amide 0.5-5 wt.% having an acyl group of average 8-16C, (B) lauric acid soap and/or myristic acid soap and palmitic acid soap and/or stearic acid soap and the blending ratio (wt.%) of the total of lauric acid and myristic acid to the total of palmitic acid and stearic acid is (lauric asid + myristic asid):(palmitic asid + sutearic asid)=3:1 to 6:1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a skin cleanser.
More specifically, the present invention relates to a skin cleansing agent that is foamed, has good foaming properties, has excellent detergency, is highly safe for the skin, and has an improved refreshing finish.

[0002]

2. Description of the Related Art Fatty acid soap-based skin cleansing agents are widely used in the field of skin cleansing agents because of their usability, stability, price and the like.

[0003]

However, when a fatty acid soap is used as a main foaming cleaning base, a large amount of lauric acid or myristic acid is mainly used to ensure sufficient foaming power. Although foaming was excellent, there were problems such as poor foam retention, and inferior refreshing feeling due to the incorporation of a polymer compound for improving stability.

[0004]

The present inventors have conducted intensive studies in view of the above circumstances. As a result, when a specific fatty acid isopropanolamide and a specific fatty acid soap are used in a specific ratio, foaming, foam retention and detergency are excellent. The present inventors have found that a skin cleanser having high skin safety and a refreshing finish can be obtained, thereby completing the present invention.

That is, the present invention relates to (A) a method in which the average carbon number is 8
0.5 to 5.0% by weight of a fatty acid isopropanolamide having an acyl group of less than １６16, (B) lauric acid soap and / or myristic acid soap, and (C) palmitic acid soap and / or stearic acid soap. Compounding ratio (weight ratio) of the total amount of lauric acid and myristic acid and the total amount of palmitic acid and stearic acid in fatty acid soap
But (lauric acid + myristic acid): (palmitic acid +
Stearic acid) = 3: 1 to 6: 1.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below in detail.

The acyl group of the fatty acid isopropanolamide used in the present invention has an average carbon number of 8 to less than 16;
Desirable are 10 to 14 acyl groups. Examples of the fatty acid isopropanolamide include, for example, undecylenic acid isopropanolamide, lauric acid isopropanolamide, myristic acid isopropanolamide, coconut oil fatty acid isopropanolamide, palm kernel oil fatty acid isopropanolamide, and the like. Preferred fatty acid isopropanolamides include Amides, coconut oil fatty acid isopropanolamide, palm kernel oil fatty acid isopropanolamide, and the like are those whose main carbon atoms have an average carbon number of 12.

The amount of these fatty acid isopropanolamides is 0.5 to 5.0% by mass based on the total amount of the skin cleanser.
Preferably it is 1.0 to 4.0% by mass. 0.5% by mass
If the amount is smaller, foaming and foam retention are not sufficient, and the composition cannot function as a skin cleanser. Also, 5.
If the amount is more than 0% by mass, the viscosity of the skin cleanser is increased, a precipitate is generated, and a problem occurs in use. These fatty acid isopropanolamides can be used alone or in combination of two or more.

As the fatty acid of the fatty acid soap used in the present invention, general fatty acids used in detergents can be used without any particular limitation. For example, lauric acid, myristic acid, palmitic acid, stearic acid, palmito oleic acid, Oleic acid, isostearic acid, linoleic acid, behenic acid and the like can be mentioned. Fatty acids having 12 or more carbon atoms are preferred from the viewpoint of reducing skin irritation. In addition, fatty acid soaps in which the fatty acid consists solely of lauric acid, myristic acid, palmitic acid, and stearic acid are particularly preferable from the viewpoint of foaming, foam retention, detergency, lack of irritation, and refreshing feeling.

As neutralizing agents for neutralizing these fatty acids,
Examples include inorganic alkali agents such as potassium hydroxide and sodium hydroxide, and organic bases such as triethanolamine and aminomethylpropanol. Preferred neutralizing agents include
Potassium hydroxide. When neutralizing the fatty acid with a neutralizing agent, it is preferable that the fatty acid be neutralized at a neutralization rate of 94 to 98%. Occurs. These fatty acids do not need to be blended as the fatty acid soap itself, and may be blended as higher fatty acids and their neutralizers.

The essential composition of the fatty acid in these fatty acid soaps in the present invention is that the blending ratio (mass ratio) of the total amount of lauric acid and myristic acid and the total amount of palmitic acid and stearic acid is (lauric acid + Myristic acid) :( palmitic acid + stearic acid) = 3: 1 to 6: 1. If this range is exceeded, basic performance such as foaming and foam retention,
Problems arise in the usability, which is not preferable.

The preferable range of the total amount of the fatty acids to be blended in the present invention is 15 to 25% by mass, more preferably 18 to 23% by mass. If the total amount of fatty acids is less than the above range, the total amount of soap is too small and cannot function as a skin cleanser on use, and if it is more than the above range, crystals may be generated at low temperatures, Other components constituting the cleaning agent, for example, a moisturizer, an emollient, and the like cannot be compounded.

The skin cleanser according to the present invention further comprises a medicinal agent, a water-soluble polymer,
Pearl brightener, moisturizer, anti-inflammatory, bactericide, preservative,
UV absorbers, antioxidants, organic and inorganic powders, pigments, and the like can be added as necessary.

[0014] The dosage form of the skin cleanser according to the present invention is not particularly limited, and may be any of viscous liquids, creams, gels, solids, and powders. Is a viscous liquid having a viscosity of 300 to 3000 centipoise.

[0015]

EXAMPLES Next, the present invention will be specifically described with reference to examples. Note that the present invention is not limited by this. The compounding amount is mass%. Prior to the examples, test methods and evaluation criteria will be described.

Detergency test A chloroform solution containing 7% of lanolin and 0.005% of Sudan III in a 5 cm × 5 cm wool muslin cloth.
4 mL is uniformly applied and dried, and the contaminated cloth is placed in an approximately 100 mL glass cylinder containing 40 mL of a 3% detergent solution, and shaken in a constant temperature bath at 40 ° C. for 15 minutes. It was rinsed well in the inside, dried, examined for reflectance, and the cleaning rate was determined by the following equation.

Cleaning rate (%) = 100 × (reflectance after cleaning−reflectance before cleaning) / (reflectance of original cloth−reflectance before cleaning)

The evaluation criteria were set as follows. ◎ ・ ・ ・ Excellent cleaning performance Cleaning rate 85% or more ○ ・ ・ ・ Good cleaning performance Cleaning rate 70% to less than 85% △ ・ ・ ・ Normal cleaning performance 55% to less than 70% × ・ ・ ・ Poor cleaning performance Cleaning Rate less than 55%

Bubbling test 40 in a cylindrical cylinder with a stirrer of 2500 mL container
400m artificial hard water (70ppm calcium carbonate)
L, and after adding 40 g of the test sample, 1 at 4500 rpm.
After stirring for minutes, the foam volume was measured. The evaluation criteria were set as follows. ：: Excellent foaming (bubble volume 1500 mL or more) ○: Good foaming (bubble volume 1200 mL or more, 1500 m)
L: Less than foaming: Normal (foam volume 800 mL or more, 1200 mL)
×: Poor foaming (foam volume less than 800 mL)

Bubble retention test 40 in a cylindrical cylinder with a stirrer of 2500 mL container
400m artificial hard water (70ppm calcium carbonate)
L, and after adding 40 g of the test sample, 1 at 4500 rpm.
The foam volume immediately after stirring for 1 minute was measured, followed by standing for 5 minutes. The foam volume after 5 minutes of standing was measured, and the foam retention was calculated by the following formula. Foam retention (%) = 100 × (Foam volume after 5 minutes of standing) /
(Foam volume immediately after stirring)

The evaluation criteria were set as follows. ◎ ・ ・ ・ Excellent foam retention 90% or more foam retention ○ ・ ・ ・ Good foam retention 80% or more and less than 90% △ ・ ・ ・ Normal foam retention 60% or more and less than 80% × ・ ・ ・ Foam Poor holding Foam retention less than 60%

Test for measuring irritation and refreshing feeling Twenty male and female subjects were allowed to clean their bodies using the prepared skin cleanser, and the irritation level and refreshing feeling were determined. The scores were classified as follows, the average value was calculated, and the stimulus and the refreshing feeling were compared. (Irritation) No irritation ・ ・ ・ 0 Slight irritation ・ ・ ・ 1 Stimulation ・ ・ ・ 2 Strong irritation ・ ・ ・ 3 (Refreshing feeling) Very refreshing ・ ・ ・ 0 Slight refreshing ・・ ・ 1 Somewhat slimy ・ ・ ・ 2 Very slimy ・ ・ ・ 3

The evaluation criteria were set as follows. ◎: The average value of the stimulus and the refreshing feeling is less than 0.5 ○: The average value of the stimulus and the refreshing feeling is 0.5 or more and less than 1.0 △: The average value of the stimulus and the refreshing feeling is 1. 0 or more and less than 1.5 × ・ ・ ・ The average value of stimulation and refreshing feeling is 1.5 or more

Examples 1 to 3 and Comparative Examples 1 to 3 A skin cleanser having the composition (% by mass) shown in Table 1 was prepared according to a conventional method, and evaluated for cleanability, foaming, foam retention, irritation and refreshing feeling. did. Table 1 also shows the results.

[0025]

[Table 1]

As is clear from Table 1, the skin cleansing compositions of the present invention of Examples 1 to 3 are clearly more cleantable than Comparative Examples 1 to 3 which do not satisfy any of the essential components of the present invention. ,
It was excellent in all items of foaming, foam retention, irritation and refreshing feeling.

Examples 4 to 7, Comparative Examples 4 to 5 Skin cleansers having the composition (% by mass) shown in Table 2 were prepared according to a conventional method, and evaluated for detergency, foaming, foam retention, irritation and refreshing feeling. did. Table 2 also shows the results.

[0028]

[Table 2]

As is clear from Table 1, the skin cleansing compositions of the present invention of Examples 4 to 7 were excellent in all of the items of detergency, foaming, foam retention, irritation and refreshing feeling. On the other hand, Comparative Examples 4 and 5, which exceed the compounding ratio of the fatty acid of the present invention, are inferior in any of the items of detergency, foaming, foam retention, irritation and refreshing feeling.

Example 8 (Body soap) A body soap was produced by a conventional method according to the following formulation.
Hereinafter, all figures are% by mass. Lauric acid monoisopropanolamide 3.0 Lauric acid 12.0 Myristic acid 4.5 Palmitic acid 1.0 Stearic acid 2.0 Potassium hydroxide 5.0 Glycerin 3.0 Dipropylene glycol 1.0 Disodium edetate 0.0 2 Ethylene glycol distearate 2.0 Trehalose undecylenate 2.0 Sodium chloride 1.0 Methylcellulose 0.5 Hydrolyzed silk liquid 0.5 Hydrolyzed conchiolin liquid 0.5 Aloe extract 0.5 Lemon extract 0.5 Pigment fine amount Fragrance 1.5 Purified water balance

Example 9 (Hand soap) A hand soap was produced according to the following formulation by a conventional method. Coconut oil fatty acid monoisopropanolamide 5.0 Lauric acid 10.0 Myristic acid 5.5 Palmitic acid 2.0 Stearic acid 2.0 Potassium hydroxide 6.2 Glycerin 10.0 Disodium edetate 0.5 Ethylene glycol distearate 2.0 Sodium chloride 1.0 Dimethyl polysiloxane (100 cps) 1.0 Dye fine amount Perfume 1.0 Purified water balance

Example 10 (Facial cleansing soap) A facial cleansing soap was produced according to the following formulation by a conventional method. Lauric acid monoisopropanolamide 3.0 Lauric acid 5.0 Myristic acid 12.0 Stearic acid 4.0 Potassium hydroxide 5.4 Glycerin 13.0 1,3-butylene glycol 12.0 Beeswax 1.0 Polyoxyethylene (60) Glyceryl monoisostearate 1.0 Polyethylene glycol 1500 5.0 Fragrance 0.5 Purified water balance

The skin cleansers of Examples 8 to 10 have
It was excellent in all items of foaming, foam retention, irritation and refreshing feeling.

[0034]

EFFECTS OF THE INVENTION The skin cleansing composition of the present invention has excellent foaming, foam retention, detergency, high safety on the skin, and a refreshing finish.

Claims (1)

[Claims] (A) a fatty acid isopropanolamide having an acyl group having an average carbon number of 8 to less than 16
5.0% by mass, (B) lauric acid soap and / or myristic acid soap, (C) palmitic acid soap and / or
Or a stearic acid soap, and the blending ratio (mass ratio) of the total amount of lauric acid and myristic acid and the total amount of palmitic acid and stearic acid in the fatty acid soap is (lauric acid + myristic acid) :( palmitin Acid + stearic acid)
= 3: 1 to 6: 1.