No-rinse wipe skin cleanser and skin cleansing method

Abstract

To provide a wiping skin-cleansing agent requiring no rinsing, which has excellent cleansing power and can be sufficiently removed after cleansing by wiping off with cloth or the like.SOLUTION: A wiping skin-cleansing agent requiring not rinsing consists of water and at least one fatty acid alkali metal salt selected from a group consisting of fatty acid potassium and fatty acid sodium, in which the fatty acid alkali metal salt contains (A) at least one selected from a group consisting of potassium oleate and sodium oleate, (B) at least one selected from a group consisting of potassium myristate and sodium myristate, and (C) at least one selected from a group consisting of potassium laurate and sodium laurate, and the mass ratios (A / (B+C)), (B / (A+C)) and (C / (A+B)) of the content of each component are within predetermined ranges.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a no-rinse wipe skin cleanser and a method for cleansing skin. [Background technology]

[0002] Skin cleansers such as soap, shampoo, and body shampoo are usually used by rinsing the cleanser with water or hot water after washing. However, there are cases where it is not possible to rinse off the cleanser with water or hot water due to illness, injury, natural disaster, or the like. In such cases, when using a general skin cleanser, there is a problem that the cleanser remains on the skin after use. In addition, there is also a problem that the remaining cleanser causes sliminess and stickiness. On the other hand, when wiping with a cloth dampened with water or the like without using a cleanser, dirt such as grime or sebum cannot be sufficiently removed. In order to solve the above problems, for example, Patent Document 1 describes a skin cleansing composition containing one or more types selected from sugar ester surfactants. However, the skin cleansing composition described in Patent Document 1 was not sufficient in terms of its ability to clean dirt. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-363062 Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention aims to provide a wipe-off skin cleanser that has excellent cleansing properties and can be sufficiently removed by wiping with a cloth or the like after cleansing, eliminating the need for rinsing, and a skin cleansing method using the same. [Means for solving the problem]

[0005] According to one aspect of the present invention, there is provided a wipe-off skin cleanser comprising water and at least one fatty acid alkali metal salt selected from the group consisting of potassium fatty acid and sodium fatty acid, wherein the fatty acid alkali metal salt is at least one selected from the group consisting of (A) potassium oleate and sodium oleate, (B) potassium myristate and sodium myristate, and (C) at least one selected from the group consisting of potassium laurate and sodium laurate. and at least one of the following: a mass ratio (A / (B+C)) of the content of the component (A) to the total amount of the component (B) and the component (C) is 0.12 or more and 4 or less; a mass ratio (B / (A+C)) of the content of the component (B) to the total amount of the component (A) and the component (C) is 0.05 or more and 4 or less; and a mass ratio (C / (A+B)) of the content of the component (C) to the total amount of the component (A) and the component (B) is 0.11 or more and 4 or less.

[0006] The wipe-off skin cleanser according to one embodiment of the present invention preferably does not contain any surfactants other than the fatty acid potassium salt and the fatty acid sodium salt.

[0007] According to one aspect of the present invention, there is provided a skin cleansing method using the wipe-type skin cleanser according to the aspect of the present invention, the skin cleansing method comprising the steps of applying the wipe-type skin cleanser to the skin and cleansing the skin, and wiping off the wipe-type skin cleanser after cleansing. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a wipe-off skin cleanser that has excellent cleansing properties and can be sufficiently removed by wiping with a cloth or the like after cleaning, eliminating the need for rinsing, as well as a skin cleansing method using the same. DETAILED DESCRIPTION OF THE INVENTION

[0009] [Skin cleanser for wiping] First, the wipe-off skin cleanser that does not require rinsing according to this embodiment will be described. The wipe-off skin cleanser of this embodiment comprises water and fatty acid potassium, as described below. The skin cleanser for wiping of this embodiment preferably consists of only water and fatty acid potassium or fatty acid sodium. Cleansing properties can be ensured by only this fatty acid potassium or fatty acid sodium. Furthermore, the skin cleanser for wiping of this embodiment does not require the use of surfactants other than fatty acid potassium and fatty acid sodium. Therefore, the burden on the human body is low. Furthermore, in order to avoid using unnecessary ingredients, it is preferable that the wipe-off skin cleanser of this embodiment does not contain any ingredients other than fatty acid potassium and fatty acid sodium (for example, organic solvents (such as alcohol), antibacterial agents, etc.).

[0010] The wipe-off skin cleanser of this embodiment may contain additives within the scope of the present invention. The additives may include at least one selected from the group consisting of pH adjusters, chelating agents, and fragrances. More specific examples of the additives include at least one selected from the group consisting of citric acid, tartaric acid, lactic acid, malic acid, oxalic acid, malonic acid, fumaric acid, succinic acid, glycolic acid, phytic acid, and salts thereof. When the above-mentioned additives are used, the wipe-off skin cleanser of the present embodiment preferably comprises water, fatty acid potassium, and the above-mentioned additives.

[0011] The wipe-off skin cleanser of this embodiment preferably consists only of water and fatty acid potassium or fatty acid sodium, and contains substantially no other components. The water used in the wipe-off skin cleanser of this embodiment is preferably purified water. Examples of purified water include reverse osmosis (RO) water, deionized water, and distilled water. Furthermore, purified water that complies with the Japanese Pharmacopoeia or the standards for quasi-drug ingredients is more preferred.

[0012] The fatty acid potassium salt used in this embodiment must contain (A) at least one selected from the group consisting of potassium oleate and sodium oleate, (B) at least one selected from the group consisting of potassium myristate and sodium myristate, and (C) at least one selected from the group consisting of potassium laurate and sodium laurate. The combination of components (A), (B), and (C) improves the cleansing properties of the wipe-off skin cleanser, and after cleansing, the cleanser can be sufficiently removed by wiping with a cloth or the like.

[0013] The component (A) used in this embodiment is a potassium salt or sodium salt of oleic acid, a fatty acid that occurs in extremely large amounts in nature, and has been confirmed to be low in burden on the human body. The potassium oleate used in this embodiment is obtained from oleic acid as a raw material and a potassium compound (such as potassium hydroxide) or a sodium compound. The raw material oleic acid usually contains impurities. These impurities are mostly linoleic acid, but also include stearic acid, linolenic acid, palmitic acid, and the like. The purity of the oleic acid is preferably 85% by mass or more, and more preferably 87% by mass or more.

[0014] The component (B) used in this embodiment is a potassium salt or sodium salt of myristic acid, a fatty acid that occurs abundantly in nature, and has been confirmed to be low in burden on the human body. The potassium myristate used in this embodiment is obtained from myristic acid as a raw material and a potassium compound (such as potassium hydroxide) or a sodium compound. The raw material myristic acid usually contains trace amounts of impurities. The purity of the myristic acid is preferably 97% by mass or more, and more preferably 99% by mass or more.

[0015] The component (C) used in this embodiment is a potassium salt or sodium salt of lauric acid, a fatty acid that occurs in extremely large amounts in nature, and has been confirmed to be low in burden on the human body. The potassium laurate used in this embodiment is obtained from lauric acid as a raw material and a potassium compound (such as potassium hydroxide) or a sodium compound. The raw material lauric acid usually contains trace amounts of impurities, such as capric acid and myristic acid. The purity of the lauric acid is preferably 97% by mass or more, and more preferably 99% by mass or more.

[0016] Impurities other than components (A), (B), and (C) include potassium caprylate, potassium palmitate, potassium stearate, potassium oleate, potassium linoleate, potassium linolenate, potassium arachidate, potassium behenate, sodium caprylate, sodium palmitate, sodium stearate, sodium oleate, sodium linoleate, sodium linolenate, sodium arachidate, and sodium behenate.

[0017] In this embodiment, the mass ratio (A / (B+C)) of the content of component (A) to the total amount of components (B) and (C) must be 0.12 or more and 4 or less. If this mass ratio is less than 0.12, the moisturizing feeling after cleansing will be insufficient. On the other hand, if this mass ratio exceeds 4, the foaming and foam quality of the wipe-off skin cleanser will be insufficient. From the viewpoint of cleanability, this mass ratio (A / (B+C)) is preferably 0.19 or more, more preferably 0.22 or more, even more preferably 0.5 or more, still more preferably 1 or more, and particularly preferably 1.25 or more. Also, from the viewpoint of cleanability, this mass ratio (A / (B+C)) is preferably 3.5 or less, more preferably 3.2 or less, even more preferably 3 or less, and particularly preferably 2.35 or less.

[0018] In this embodiment, the mass ratio (B / (A+C)) of the content of component (B) to the total amount of components (A) and (C) must be 0.05 or more and 4 or less. If this mass ratio is less than 0.05, the foaming and foam quality of the wipe-off skin cleanser will be insufficient. On the other hand, if this mass ratio exceeds 4, the cleanser will be difficult to wipe off, causing problems with the cleanser's residue and reducing the stability of the liquid. From the viewpoints of the residual property, liquid stability, and cleaning performance of the detergent, this mass ratio (B / (A+C)) is preferably 0.11 or more, more preferably 0.15 or more, and particularly preferably 0.22 or more. From the viewpoints of the residual property, liquid stability, and cleaning performance of the detergent, this mass ratio (B / (A+C)) is preferably 3 or less, more preferably 2 or less, even more preferably 1.5 or less, and particularly preferably 0.5 or less.

[0019] In this embodiment, the mass ratio (C / (A+B)) of the content of component (C) to the total amount of components (A) and (B) must be 0.11 or more and 4 or less. If this mass ratio is less than 0.11, the foaming of the wipe-off skin cleanser will be insufficient. On the other hand, if this mass ratio exceeds 4, the moisturizing feeling after cleansing will be insufficient. From the viewpoint of cleanability, this mass ratio (C / (A+B)) is preferably 0.12 or more, more preferably 0.15 or more, and particularly preferably 0.19 or more. Also, from the viewpoint of cleanability, this mass ratio (C / (A+B)) is preferably 3 or less, more preferably 2 or less, even more preferably 1 or less, and particularly preferably 0.5 or less.

[0020] In this embodiment, the content of fatty acid potassium is preferably 10% by mass or more and 25% by mass or less, and more preferably 1% by mass or more and 30% by mass or less, based on the total amount of the wipe-off skin cleanser. If the content of fatty acid potassium is equal to or more than the lower limit, the cleansing properties can be further improved. On the other hand, if the content of fatty acid potassium is equal to or less than the upper limit, the stability of the liquid state can be improved.

[0021] The wipe-off skin cleanser of this embodiment may contain additives within the scope of the present invention. The additives may include at least one selected from the group consisting of pH adjusters and chelating agents. More specific examples of the additives include at least one selected from the group consisting of citric acid, tartaric acid, lactic acid, malic acid, oxalic acid, malonic acid, fumaric acid, succinic acid, glycolic acid, phytic acid, and salts thereof. When the above-mentioned additives are used, the wipe-off skin cleanser of the present embodiment preferably comprises water, fatty acid potassium, and the above-mentioned additives.

[0022] The wipe-off skin cleanser of this embodiment can be produced by blending water and fatty acid potassium salt in the above-mentioned predetermined ratio and stirring and mixing them.

[0023] [Skin cleansing method] Next, the skin cleansing method of this embodiment will be described. The skin cleansing method of this embodiment is a skin cleansing method using the wiping skin cleanser of this embodiment, and is a method including a cleaning step and a wiping step, which will be described below.

[0024] In the cleaning step, the skin cleanser for wiping is applied to the skin and then cleansed. Here, the wipe-off skin cleanser is preferably in foam form. A conventionally known method using a whisk or the like can be used to convert a liquid wipe-off skin cleanser into a foam-form wipe-off skin cleanser. The wipe-off skin cleanser may be foamed after being applied to the skin. Examples of skin include skin of the human body (hands, arms, face, head, neck, trunk, waist, legs, etc.) and skin of animals. The application method can be any of the conventionally known methods for applying wipe-off skin cleansers, specifically, (i) a method in which a packaged wipe-off skin cleanser is squeezed out of the container, lathered, and applied, and (ii) a method in which the wipe-off skin cleanser is rubbed onto the skin with the hands and lathered. The temperature of the wipe-off skin cleanser is not particularly limited as long as it is a temperature that does not cause any problems when it comes into contact with human skin. The amount of the wipe-off skin cleanser to be applied is not particularly limited and may be determined appropriately depending on the area to be cleaned.

[0025] In the wiping step, after washing, the skin cleanser for wiping is wiped off. When wiping off the skin cleanser for wiping, for example, cloth (towel, nonwoven fabric, woven fabric, mesh fabric, etc.) and paper (tissue paper, etc.) can be used. When wiping off the skin cleanser, it is preferable to moisten the cloth with water, etc. Examples of water include purified water, saline, and tap water. The temperature of the water is not particularly limited, as long as it is a temperature that is safe for contact with human skin. Furthermore, after wiping with a damp cloth, it is more preferable to further wipe with a dry cloth. Furthermore, there is no particular limit to the number of times wiping is performed, but it is more preferable to wipe twice or more.

[0026] As described above, the skin cleansing method of this embodiment allows the use of a wipe-off skin cleanser to cleanse skin even when the cleanser cannot be washed away with water, etc. Furthermore, since the wipe-off skin cleanser of this embodiment imposes little strain on the human body, the skin cleansing method of this embodiment allows the skin to be cleaned in a manner that imposes little strain on the human body. [Example]

[0027] Next, the present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these examples in any way.

[0028] [Example 1] First, oleic acid (Tokyo Chemical Industry Co., Ltd., pure content: 87% by mass), myristic acid (Tokyo Chemical Industry Co., Ltd., pure content: 99% by mass or more), lauric acid (Tokyo Chemical Industry Co., Ltd., pure content: 99% by mass or more), and 85% potassium hydroxide (Kanto Chemical Co., Ltd.) were prepared. Also, a beaker and a stirrer (IKA Corporation, "C-MAG HS 7") were prepared. 79.63 g of oleic acid, 18.25 g of 85% potassium hydroxide, and 604.47 g of purified water were added to a beaker, and the mixture was heated to 50°C while stirring with a stirrer to prepare a 350 mM potassium oleate aqueous solution (hereinafter also referred to as "C18:1K aqueous solution"). 127.90 g of myristic acid, 36.46 g of 85% potassium hydroxide, and 1,435.16 g of purified water were added to a beaker, and the mixture was heated to 50°C while stirring with a stirrer to prepare a 350 mM aqueous potassium myristate solution (hereinafter also referred to as "C14K aqueous solution"). 49.08 g of lauric acid, 16.03 g of 85% potassium hydroxide, and 634.92 g of purified water were added to a beaker, and the mixture was heated to a temperature of 50°C while stirring with a stirrer to prepare a 350 mM aqueous potassium laurate solution (hereinafter also referred to as "C12K aqueous solution"). Next, the C18:1K aqueous solution, the C14K aqueous solution, and the C12K aqueous solution were mixed to prepare a detergent (350 mM aqueous solution). The contents and mass ratios of components (A), (B), and (C) in Example 1 are shown in Table 1.

[0029] [Examples 2 to 7 and Comparative Examples 1 to 9] A detergent (350 mM aqueous solution) was obtained in the same manner as in Example 1, except that the contents of component (A), component (B), and component (C) were each as shown in Table 1.

[0030] [Cleaning agent evaluation] The detergents were evaluated (foaming, foam quality, moisturizing feeling after washing, liquid stability, and residue after wiping) using the following methods. The results are shown in Table 1. The cleansers of Comparative Examples 8 and 9 had precipitates and were problematic in terms of liquid stability, so they were not evaluated for foaming, foam quality, or moisturizing feeling after cleansing. Further, the residue after wiping was evaluated only for the cleaning agents of Example 4 and Comparative Examples 8 and 9. (1) Foaming 3 mL of detergent and 27 mL of purified water were placed in a mixer (Panasonic, "National MX-X53-G Fiber Mixer") and the lid was closed. The mixer was turned on, stirred for 10 seconds, and then stopped. The lid was then opened, a ruler was inserted, and the foam height was measured. Based on the foam height, foaming was evaluated according to the following criteria. ◎: The height of the bubbles is 6.5 cm or more. ○: The foam height is 5.0 cm or more and less than 6.5 cm. △: The foam height is 3.5 cm or more and less than 5.0 cm. ×: The height of the bubbles is less than 3.5 cm. (2) Foam quality The detergent was diluted two-fold to prepare a sample (175 mM). 3 mL of the sample was taken in the hand, and the sample was lathered using the same procedure as when washing hands. The lather quality was then evaluated according to the following criteria: ◎: Fine, three-dimensional, and bouncy foam. ◯: Normal good foam. △: Slightly watery and flat foam, but usable. ×: Not enough foam. (3) Moisturizing feeling after cleansing The detergent was diluted two-fold to prepare a sample (175 mM). 3 mL of the sample was taken into the hand, lathered using the usual hand washing procedure, and washed in the following order: palm, back of hand, between the fingers, toes, thumb, and wrist, followed by rinsing with tap water. The moisturizing sensation after washing was evaluated according to the following criteria: ◎: When you press the back of your hand with the thumb of your other hand, your fingers slip. ○: When you press the back of your hand with the thumb of your other hand, your fingers slip slightly. △: When I press the back of my hand with the thumb of my other hand, my fingers don't slip as much. ×: When I press the back of my hand with the thumb of my other hand, my fingers don't move at all. (4) Liquid stability The detergent was prepared and left at room temperature for 1 hour, after which its condition was visually inspected and the liquid stability was evaluated according to the following criteria. Good: No precipitate formed, and the product is liquid and fluid. ×: Precipitation was observed. (5) Residual residue after wiping The measurement was carried out using the FTIR-ATR method (manufactured by JASCO Corporation, device name "FTIR4200 type infrared spectrometer"). The skin on the upper arm of a healthy skin monitor subject was placed in close contact with the FTIR-ATR base, and the FT-IR spectrum of the bare skin was measured using the total reflection method. Next, approximately 0.01 g of foam cleanser was applied to the measurement area on a circular area with a diameter of 18 mm, and after leaving it for 2 minutes, the FT-IR spectrum of the unwashed bare skin after application was measured using the total reflection method. Next, 70 mL of pure water was added to a 100% cotton (25 cm x 25 cm) to prepare a wet towel heated to 50°C, and the area to which the detergent had been applied was wiped three times with this wet towel. Finally, the area where the cleanser was applied was wiped twice with a dry towel, and the FT-IR spectrum of the bare skin after wiping was measured. Based on these FT-IR spectra, 1400 cm -1 The residual ratio was calculated by subtracting the water and bare skin of each nearby band. The residual ratio is the ratio of absorbance of bare skin after wiping to that of bare skin after application and not washed (bare skin after wiping / bare skin after application and not washed). If this value is negative, the residual after wiping was judged as "Good", and if this value is 0 or more, the residual after wiping was judged as "Poor".

[0031] [Table 1]

[0032] As shown in Table 1, the detergents obtained in Examples 1 to 7 were found to be good in foaming, foam quality, moisturizing feeling after washing, and liquid stability. This confirmed that the detergents obtained in Examples 1 to 7 had excellent cleansing properties. Furthermore, the detergent obtained in Example 4 was found to have good residue after wiping. Among fatty acid potassium salts, potassium myristate is known to be prone to residue problems. In contrast, only Comparative Example 9, in which the mass ratio (B / (A+C)) was 19, had a problem with residue after wiping, while Comparative Example 8, in which the mass ratio (B / (A+C)) was 4.88, also had good residue after wiping. This confirms that the detergent of the present invention, in which the mass ratio (B / (A+C)) is 4 or less, can be sufficiently removed by wiping with a cloth or the like after cleaning.

Claims

1. A wipe-off skin cleanser comprising water and at least one fatty acid alkali metal salt selected from the group consisting of fatty acid potassium salts and fatty acid sodium salts, The fatty acid alkali metal salt contains (A) at least one selected from the group consisting of potassium oleate and sodium oleate, (B) at least one selected from the group consisting of potassium myristate and sodium myristate, and (C) at least one selected from the group consisting of potassium laurate and sodium laurate, a mass ratio (A / (B+C)) of the content of the component (A) to the total amount of the component (B) and the component (C) is 1 or more and 2.57 or less; a mass ratio (B / (A+C)) of the content of the component (B) to the total amount of the component (A) and the component (C) is 0.05 or more and 4 or less; a mass ratio (C / (A+B)) of the content of the component (C) to the total amount of the component (A) and the component (B) is 0.11 or more and 4 or less; Contains no surfactants other than the fatty acid potassium and fatty acid sodium A wipe-off skin cleanser that does not require rinsing.

2. A wipe-off skin cleanser comprising water and at least one fatty acid alkali metal salt selected from the group consisting of fatty acid potassium salts and fatty acid sodium salts, The fatty acid alkali metal salt contains (A) at least one selected from the group consisting of potassium oleate and sodium oleate, (B) at least one selected from the group consisting of potassium myristate and sodium myristate, and (C) at least one selected from the group consisting of potassium laurate and sodium laurate, a mass ratio (A / (B+C)) of the content of the component (A) to the total amount of the component (B) and the component (C) is 0.12 or more and 4 or less; a mass ratio (B / (A+C)) of the content of the component (B) to the total amount of the component (A) and the component (C) is 0.05 or more and 4 or less; a mass ratio (C / (A+B)) of the content of the component (C) to the total amount of the component (A) and the component (B) is 2.57 or more and 4 or less; Contains no surfactants other than the fatty acid potassium and fatty acid sodium A wipe-off skin cleanser that does not require rinsing.

3. A skin cleansing method using the wipe-type skin cleanser according to claim 1 or 2, applying the wipe-off skin cleanser to the skin and cleaning it; After washing, wiping off the wipe-off skin cleanser; A skin cleansing method comprising:

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