Oil-in-water emulsion cosmetics

Abstract

To provide an oil-in-water type emulsion cosmetic which excels in emulsion stability, has quick compatibility with skin during application and excels in lack of stickiness to skin after application.SOLUTION: There is provided an oil-in-water type emulsion cosmetic which comprises a component (A): linear saturated higher alcohol having 16 to 22 carbon atoms, a component (B): linear saturated higher alcohol having 16 to 22 carbon atoms, a component (C): nonionic surfactant having an HLB of 8 or less, a component (D): sodium stearoyl lactylate and / or sodium stearoyl methyl taurate and a component (D): ethanol and excels in emulsion stability, has quick compatibility with skin during application and excels in lack of stickiness to skin after application.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an oil-in-water emulsion cosmetic which has excellent emulsion stability, is quickly absorbed into the skin when applied, and is non-sticky on the skin after application. [Background technology]

[0002] Oil-in-water emulsion cosmetics, such as milky lotions and creams, are often used in skin care applications to prevent skin drying and to replenish moisture and oil in the skin to keep it moist. Conventionally, oil-in-water emulsion cosmetics contain polyhydric alcohols and various oils to improve the moisturizing feeling, but as the content of these increases, the moisturizing feeling improves, but there are problems such as slow absorption upon application and increased stickiness of the skin after application. Furthermore, surfactants and polymeric emulsifiers are necessary to prepare emulsion cosmetics, and the inclusion of these ingredients also causes increased stickiness of the skin after application.

[0003] There have been many studies on improving skin compatibility during application and stickiness after application while maintaining emulsion stability and moisturizing feeling of the skin. Patent Document 1 discloses an emulsion cosmetic that improves sliminess and stickiness during application using polyhydric alcohols containing glycosyl trehalose, and Patent Document 2 discloses an emulsion composition that improves stickiness using carboxyvinyl polymers and alkyl-modified carboxyvinyl polymers. However, these cosmetics have a problem that although they can suppress stickiness caused by polyhydric alcohols and water-soluble polymers, they are not effective against stickiness of the skin caused by oils. Patent Document 3 discloses a skin cream that suppresses stickiness while maintaining moisturizing feeling by combining glyceryl (ethylhexanoate / stearate / adipic acid), higher alcohols, liquid oils, nonionic surfactants, and water. However, in the case of this skin cream, although there is an improvement in compatibility during application and stickiness of the skin after application, the emulsion stability is not satisfactory.

[0004] Furthermore, among skin care applications, cosmetics used on the body, particularly on the hands and fingers, tend to leave the skin feeling sticky after application because there are many opportunities to put on clothes or touch objects after application. Therefore, there is a strong demand for cosmetics that provide a moisturizing feeling but do not leave the skin feeling sticky after application. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2018-203634 A [Patent Document 2] JP 2014-31337 A [Patent Document 3] JP 2019-172625 A Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present invention is to provide an oil-in-water emulsion cosmetic which has excellent emulsion stability, is quickly absorbed into the skin when applied, and is non-sticky on the skin after application. [Means for solving the problem]

[0007] In view of these circumstances, the present inventors conducted extensive research and discovered that an oil-in-water emulsion cosmetic containing component (A) a linear saturated higher alcohol having 16 to 22 carbon atoms, component (B) a linear saturated higher fatty acid having 16 to 22 carbon atoms, component (C) a nonionic surfactant with an HLB of 8 or less, component (D) sodium stearoyl lactylate and / or sodium methyl stearoyl taurate, and component (E) ethanol has excellent emulsion stability, is quickly absorbed into the skin upon application, and is non-sticky after application, thereby completing the present invention.

[0008] That is, the present invention relates to the following components (A) to (E); (A) Straight-chain saturated higher alcohol with 16 to 22 carbon atoms (B) Straight-chain saturated higher fatty acids with 16 to 22 carbon atoms (C) Nonionic surfactants with HLB of 8 or less (D) Sodium stearoyl lactylate and / or sodium stearoyl methyl taurate (E) Ethanol The present invention relates to an oil-in-water emulsion cosmetic composition comprising: Effect of the Invention

[0009] The oil-in-water emulsion cosmetic of the present invention has excellent emulsion stability, is quickly absorbed into the skin when applied, and leaves the skin feeling non-sticky after application. Each of the constituent components will be described in detail below. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Examples of the linear saturated higher alcohol having 16 to 22 carbon atoms (A) of the present invention include cetyl alcohol, stearyl alcohol, behenyl alcohol, and hydrogenated rapeseed oil alcohol. These components may be used alone or in combination of two or more. Commercially available products include cetyl alcohol NX, stearyl alcohol NX, behenyl alcohol, and Alcohol No. 20-B (manufactured by Kokyu Alcohol Kogyo Co., Ltd.). From the viewpoint of emulsion stability, behenyl alcohol and hydrogenated rapeseed oil alcohol are preferred, and hydrogenated rapeseed oil alcohol is more preferred.

[0011] The content of the linear saturated higher alcohol having 16 to 22 carbon atoms (A) of the present invention is not particularly limited, but is preferably 0.1 to 0.7% by weight, more preferably 0.2 to 0.5% by weight, based on the oil-in-water emulsion cosmetic. If it is less than 0.1% by weight, it may cause a decrease in usability such as stickiness on the skin after application, or a decrease in emulsion stability. On the other hand, if it exceeds 0.7% by weight, it may cause a decrease in emulsion stability such as crystal precipitation.

[0012] Examples of the linear saturated higher fatty acid having 16 to 22 carbon atoms as component (B) of the present invention include palmitic acid, stearic acid, and behenic acid. These components may be used alone or in combination of two or more. Commercially available products that can be used include NAA-160, NAA-1865, and NAA-222S (manufactured by NOF Corporation). From the viewpoint of emulsion stability, behenic acid is preferred.

[0013] The content of the linear saturated higher fatty acid having 16 to 22 carbon atoms as component (B) of the present invention is not particularly limited, but is preferably 0.1 to 0.5% by weight, more preferably 0.2 to 0.4% by weight, based on the oil-in-water emulsion cosmetic. If it is less than 0.1% by weight, it may cause a decrease in usability such as stickiness on the skin after application, or a decrease in emulsion stability. On the other hand, if it exceeds 0.5% by weight, it may cause a decrease in emulsion stability such as crystal precipitation.

[0014] Examples of the nonionic surfactant with HLB8 or less as component (C) of the present invention include sorbitan stearate and glyceryl stearate. These components may be used alone or in combination of two or more. Commercially available products include NIKKOL SS-10V and NIKKOL MGS-AV (manufactured by Nikko Chemicals Co., Ltd.). From the viewpoint of emulsion stability, sorbitan stearate is preferred. The HLB (Hydrophile-Lipophile Balance) referred to here indicates the molecular weight of the hydrophilic group portion in the total molecular weight of the surfactant, and for nonionic surfactants, it can be calculated by Griffin's formula: HLB=20×Mw / M (M is the molecular weight of the nonionic surfactant, and Mw is the molecular weight of the hydrophilic group portion).

[0015] The content of the component (C) nonionic surfactant with HLB of 8 or less in the present invention is not particularly limited, but is preferably 0.2 to 0.8% by weight, more preferably 0.3 to 0.5% by weight, based on the oil-in-water emulsion cosmetic. If it is less than 0.2% by weight, emulsion particles may become coarse, and emulsion stability may decrease. On the other hand, if it exceeds 0.8% by weight, usability may decrease, such as stickiness of the skin after application.

[0016] The component (D) of the present invention, sodium stearoyl lactylate and / or sodium stearoyl methyl taurate, are both anionic surfactants. These components may be used alone or in combination of two kinds. Commercially available products include sodium stearoyl lactylate (manufactured by Musashino Chemical Laboratory Co., Ltd.) and NIKKOL SMT (manufactured by Nikko Chemicals Co., Ltd.). From the viewpoint of emulsion stability, sodium stearoyl lactylate is preferred.

[0017] The content of component (D) sodium stearoyl lactylate and / or sodium stearoyl methyl taurate in the oil-in-water emulsion cosmetic is not particularly limited, but is preferably 0.03 to 0.5% by weight, more preferably 0.05 to 0.3% by weight. If it is less than 0.03% by weight, emulsion particles may become coarse, resulting in a decrease in emulsion stability. On the other hand, if it exceeds 0.5% by weight, usability may decrease, such as stickiness on the skin after application.

[0018] The total amount of the oil phase excluding components (C) and (D) is preferably 2 to 15% by weight, more preferably 3 to 10% by weight. If it is less than 2% by weight, a decrease in emulsion stability, such as crystal precipitation, may occur. On the other hand, if it exceeds 15% by weight, a decrease in usability, such as increased stickiness on the skin after application, may occur. The oil phase here refers to the components in the cosmetic preparation excluding water and water-soluble components (excluding components (C) and (D)).

[0019] The content of ethanol (E) of the present invention is not particularly limited, but is preferably 2 to 8% by weight, more preferably 3 to 6% by weight, based on the oil-in-water emulsion cosmetic. If it is less than 2% by weight, it may cause a decrease in usability, such as a decrease in skin compatibility upon application and an increase in stickiness of the skin after application. On the other hand, if it exceeds 8% by weight, it may cause a decrease in emulsion stability.

[0020] Furthermore, the oil-in-water emulsion cosmetic of the present invention contains the above-mentioned components (A) to (E) as essential components, but preferably further contains an alkyl-modified carboxyvinyl polymer as component (F).

[0021] The alkyl-modified carboxyvinyl polymer (F) used in the present invention is preferably an (acrylates / alkyl acrylate (C10-C30)) crosspolymer. Commercially available products include Pemulen TR-1 and Pemulen TR-2 (manufactured by Lubrizol Japan Co., Ltd.).

[0022] The content of the alkyl-modified carboxyvinyl polymer (Component (F)) of the present invention is not particularly limited, but is preferably 0.05 to 0.4% by weight, more preferably 0.1 to 0.2% by weight, based on the oil-in-water emulsion cosmetic. If it is less than 0.05% by weight, emulsion stability may decrease. On the other hand, if it exceeds 0.4% by weight, usability may decrease, such as poor skin compatibility upon application and sticky skin after application.

[0023] The oil-in-water emulsion cosmetic of the present invention may contain, as necessary, components other than the above-mentioned components (A) to (F) that are usually used in skin external preparations such as cosmetics and medicines, within the scope that does not impair the effects of the present invention. The components other than the above-mentioned components (A) to (F) are not particularly limited, and may contain, for example, oils other than components (A) and (B), surfactants other than components (C) and (D), water-soluble polymers other than component (F), pH adjusters, chelating agents, moisturizers, aqueous components, antioxidants, cosmetic components, preservatives, film-forming agents, anti-fading agents, UV absorbers, antifoamers, fragrances, plant extracts, etc., as appropriate to impart various effects.

[0024] The form of the oil-in-water emulsion cosmetic of the present invention is not particularly limited, and a wide range of forms from emulsion to cream are possible. Among them, emulsion is preferred from the viewpoint of usability. In particular, it is preferred that the viscosity at 25°C measured with a B-type viscometer (No. 3 rotor, 30 rpm, 30 seconds) is 4,000 mPa s or less.

[0025] Furthermore, the area on which the oil-in-water emulsion cosmetic of the present invention is used is not particularly limited, and it can be used on the face, body, etc. Among these, from the viewpoint of ease of use, it is preferably used on the body, and more preferably used on the hands and fingers. EXAMPLES

[0026] The present invention will be described in more detail below with reference to examples. Note that the present invention is not limited to the following examples. In addition, the contents in the following examples are expressed in weight percent unless otherwise specified.

[0027] Prior to the examples, the effectiveness test method used in the present invention will be described.

[0028] [Emulsification stability] Each cosmetic example was filled into a glass container and stored for 3 months in a thermostatic chamber at 40° C. The appearance was evaluated by visual observation and the emulsion particles were evaluated by microscopic observation, and judged according to the following criteria. (Evaluation Criteria) ⊚: No difference was observed in appearance and emulsion particles from the initial state. ◯: The emulsion particles are larger than in the initial state, but no difference is observed in appearance. ×: The emulsion particles have become larger than in the initial state, and changes in appearance such as creaming or separation are observed.

[0029] [Usability] (1) Quickness of familiarity A panel of 20 experts conducted a usage test on each cosmetic example to determine how quickly it absorbed into the skin when applied, and rated it on a two-point scale, either "fast" or "not fast," according to the following criteria: (Evaluation Criteria) ◎: Of 20 people, more than 15 people answered that they quickly became accustomed to it. ○: Of 20 people, 10 to 14 people answered that they became familiar with it quickly. △: Of 20 people, 5 to 9 people answered that they got used to it quickly. ×: Of 20 people, 4 or fewer answered that they got used to it quickly.

[0030] (2) Non-sticky A panel of 20 experts conducted a use test on each cosmetic example to check whether it was sticky after application to the skin, and rated it on a two-level scale of "yes" or "no" according to the following criteria. (Evaluation Criteria) ◎: Of 20 people, 15 or more people answered that it was not sticky. ○: Of 20 people, 10 to 14 people answered that it was not sticky. △: 5 to 9 out of 20 people answered that it was not sticky. ×: Of 20 people, 4 or less people answered that it was not sticky.

[0031] Oil-in-water emulsion cosmetics having the formulations shown in Tables 1 to 3 were prepared, and the emulsion stability and usability were evaluated according to the above-mentioned criteria.

[0032] The oil-in-water emulsion cosmetic obtained according to the formulation in Table 1 was prepared by the manufacturing method described below. (Preparation method) Components 1 to 13 were heated to 75 to 80°C and uniformly dissolved. Components 14 to 20 were uniformly dispersed using a homomixer. Components 14 to 21 heated to 80 to 85°C were added to components 1 to 13 heated to 75 to 80°C, and emulsified by operating the homomixer. The mixture was then cooled, and component 22 was gradually added at 45°C. The mixture was then cooled to 30°C to obtain the oil-in-water emulsion cosmetic preparations of each example in Table 1.

[0033] [Table 1]

[0034] The results shown in Table 1 show that the cosmetics (Examples 1 to 10) containing (A) a linear saturated higher alcohol having 16 to 22 carbon atoms, (B) a linear saturated higher fatty acid having 16 to 22 carbon atoms, (C) a nonionic surfactant with an HLB of 8 or less, (D) sodium stearoyl lactylate and / or sodium methyl stearoyl taurate, and (E) ethanol have excellent emulsion stability and usability. On the other hand, the cosmetics not containing component (A) (Comparative Example 1), the cosmetics containing a linear saturated higher alcohol having less than 16 carbon atoms instead of component (A) (Comparative Example 2), and the cosmetics containing a branched higher alcohol instead of component (A) (Comparative Example 3) showed poor emulsion stability and poor usability.

[0035] The oil-in-water emulsion cosmetic obtained according to the formulation in Table 2 was prepared by the manufacturing method described below. (Preparation method) Components 1 to 12 were heated to 75 to 80°C and uniformly dissolved. Components 13 to 20 were uniformly dispersed using a homomixer. Components 13 to 20 heated to 80 to 85°C were added to components 1 to 12 heated to 75 to 80°C, and emulsified by operating the homomixer. The mixture was then cooled, and component 21 was gradually added at 45°C. The mixture was then cooled to 30°C to obtain the oil-in-water emulsion cosmetic preparations of each example in Table 2.

[0036] [Table 2]

[0037] From the results shown in Table 2, it can be seen that the cosmetics (Examples 11 to 19) containing (A) a linear saturated higher alcohol having 16 to 22 carbon atoms, (B) a linear saturated higher fatty acid having 16 to 22 carbon atoms, (C) a nonionic surfactant with an HLB of 8 or less, (D) sodium stearoyl lactylate and / or sodium methyl stearoyl taurate, and (E) ethanol have excellent emulsion stability and usability. On the other hand, the cosmetics not containing component (B) (Comparative Example 4) and the cosmetics containing a branched higher fatty acid instead of component (B) (Comparative Example 5) showed deterioration in emulsion stability and usability. Furthermore, the cosmetics not containing component (C) (Comparative Example 6) and the cosmetics containing a nonionic surfactant with an HLB of more than 8 instead of component (C) (Comparative Example 7) showed deterioration in emulsion stability and usability.

[0038] The oil-in-water emulsion cosmetic obtained according to the formulation in Table 3 was prepared by the manufacturing method described below. (Preparation method) Components 1 to 8 were heated to 75 to 80°C and uniformly dissolved. Components 9 to 19 were uniformly dispersed using a homomixer. Components 9 to 19 heated to 80 to 85°C were added to components 1 to 8 heated to 75 to 80°C, and emulsified by operating the homomixer. The mixture was then cooled, and component 20 was gradually added at 45°C. The mixture was then cooled to 30°C to obtain the oil-in-water emulsion cosmetic preparations of each example in Table 3.

[0039] [Table 3]

[0040] From the results shown in Table 3, it can be seen that the cosmetics (Examples 20 to 27) containing (A) a linear saturated higher alcohol having 16 to 22 carbon atoms, (B) a linear saturated higher fatty acid having 16 to 22 carbon atoms, (C) a nonionic surfactant having an HLB value of 8 or less, (D) sodium stearoyl lactylate and / or sodium stearoyl methyl taurate, and (E) ethanol have excellent emulsion stability and usability. On the other hand, the cosmetics not containing component (D) (Comparative Example 8), the cosmetics containing an anionic surfactant having a glutamate salt as a hydrophilic group instead of component (D) (Comparative Example 9), and the cosmetics containing an anionic surfactant having a 12-carbon hydrophobic group instead of component (D) (Comparative Example 10) showed poor emulsion stability and poor usability. Furthermore, the cosmetics not containing component (E) (Comparative Example 11) showed poor usability.

[0041] The components shown in Tables 1 to 3 were the following products. *1 Hynole 14SS (Kyukyu Alcohol Kogyo Co., Ltd.) *2 Lisonol 18SP (manufactured by Kokyu Alcohol Kogyo Co., Ltd.) *3 Cetyl Alcohol NX (Kyukyu Alcohol Kogyo Co., Ltd.) *4 Stearyl Alcohol NX (Kyukyu Alcohol Kogyo Co., Ltd.) *5 Behenyl alcohol (Kyushu Alcohol Kogyo Co., Ltd.) *6 Alcohol No. 20-B (Kyukyu Alcohol Kogyo Co., Ltd.) *7 NAA-222S (NOF Corporation) *8 NIKKOL SS-10V (manufactured by Nikko Chemicals Co., Ltd.) *9 Sodium stearoyl lactylate (Musashino Chemical Laboratory Co., Ltd.) *10 Pemulen TR-1 (manufactured by Lubrizol Japan, Ltd.) *11 Isostearic acid EX (Kyushu Alcohol Kogyo Co., Ltd.) *12 NAA-160 (NOF Corporation) *13 NAA-1865 (NOF Corporation) *14 NIKKOL TMGS-15V (manufactured by Nikko Chemicals Co., Ltd.) *15 NIKKOL SMT (manufactured by Nikko Chemicals Co., Ltd.) *16 Amisoft HS-11P(F) (manufactured by Ajinomoto Co., Inc.) *17 NIKKOL LMT (manufactured by Nikko Chemicals Co., Ltd.)

[0042] Example 28 Body Milk Ingredients Content (wt%) (1) Squalane 4.00 (2) Diisostearyl malate 0.50 (3) Octyldodecyl myristate 1.00 (4) Vaseline 0.50 (5) Shea butter 0.10 (6) Phytosteryl Macadamiate 0.30 (7) Ceramide 0.01 (8) Hydrogenated rapeseed oil alcohol 0.25 (9) Behenic acid 0.30 (10) Sorbitan stearate 0.20 (11) Sodium stearoyl lactylate 0.10 (12) Remaining purified water (13) EDTA-2Na 0.05 (14) (Acrylates / C10-C30 alkyl acrylate) crosspolymer 0.18 (15) Xanthan gum 0.02 (16) Sodium hyaluronate 0.01 (17) Glycerin 6.00 (18) Pentylene glycol 2.00 (19) Methylparaben 0.20 (20) 1,3-butylene glycol 4.00 (21) AMPD 0.15 (22) Polyquaternium-51 1.00 (23) Ethanol 5.00

[0043] (Preparation method) Components (1) to (11) were heated to 75 to 80°C and uniformly dissolved. Components (12) to (21) were uniformly dispersed using a homomixer. Components (12) to (21) heated to 80 to 85°C were added to components (1) to (11) heated to 75 to 80°C, and the homomixer was operated to emulsify. The mixture was then cooled, and components (22) and (23) were gradually added at 45°C. The mixture was then cooled to 30°C to obtain the oil-in-water emulsion cosmetic of Example 28.

[0044] The cosmetic preparation of Example 28, which contained (A) a linear saturated higher alcohol having 16 to 22 carbon atoms, (B) a linear saturated higher fatty acid having 16 to 22 carbon atoms, (C) a nonionic surfactant having an HLB of 8 or less, (D) sodium stearoyl lactylate and / or sodium methyl stearoyl taurate, and (E) ethanol, was an oil-in-water emulsion cosmetic that had excellent emulsion stability, was quickly absorbed into the skin upon application, and was excellent in terms of non-stickiness on the skin after application. [Industrial Applicability]

[0045] According to the present invention, it is possible to provide an oil-in-water emulsion cosmetic which has excellent emulsion stability, is quickly absorbed into the skin when applied, and leaves the skin without feeling sticky after application.

Claims

1. The following components (A) to (F): (A) Hydrogenated rapeseed oil alcohol (B) Straight-chain saturated higher fatty acid having 16 to 22 carbon atoms (C) Nonionic surfactants with an HLB of 8 or less (D) Sodium stearoyl lactylate and / or sodium stearoyl methyl taurate (E) Ethanol (F) Acrylates / alkyl acrylate (C10-30) crosspolymer The oil-in-water emulsion cosmetic comprises: a) a component (A) content of 0.1 to 0.7% by weight; b) a component (C) content of 0.2 to 0.8% by weight; and c) a total amount of the oil phase excluding components (C) and (D) of 2 to 15% by weight.

2. 2. The oil-in-water emulsion cosmetic according to claim 1, characterized in that the content of component (E) ethanol is 2 to 8% by weight.

3. 3. The oil-in-water emulsion cosmetic according to claim 1, wherein the component (C) nonionic surfactant having an HLB of 8 or less is sorbitan stearate.

Images