JP2001233729A - Oil-in-water emulsified type multilayered cosmetic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oil-in-water emulsified type multilayered cosmetic requiring short time for separating into a layered formation and having a beautiful appearance. SOLUTION: This oil-in-water emulsified type multilayered cosmetic is characterized in that the cosmetic comprises polyethylene glycol having 150-25,000 mean degree of polymerization, a polyoxyethylene-based nonionic surfactant and an oil ingredient and the viscosity of the composition is <50 mPa.s at 30 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil-in-water type multi-layer cosmetic, and more particularly to an improvement in dispersibility during shaking and layer forming ability including appearance.

[0002]

2. Description of the Related Art A multi-layer cosmetic is a liquid cosmetic comprising two or more layers, and is often composed of two layers, an oil layer and an aqueous layer or an aqueous layer and a powder layer. All of them become uniform emulsion liquid and powder dispersion by shaking at the time of use, and after standing, the dispersed oil and powder gather at the upper or lower part and become multilayer again after use. It is.

[0003] Among them, in the case of a multi-layer cosmetic formed of an oil layer-aqueous layer, by blending a small amount of a surfactant or the like, it becomes temporarily emulsified during shaking and can be easily used. In this case, the temporarily emulsified oil component is
Over time, they gradually coalesce to form large oil droplets and collect at the top, forming a uniform oil layer. A problem with this type of multi-layer cosmetics is that if the temporarily formed emulsification is present to some extent or more stably, it will not be possible to separate it into a clean two-layer form.
In order to separate them into clean two layers, it is necessary to balance delicate emulsification on the formulation, which limits the width of the formulation and makes it difficult to have a wide feeling in use. Disadvantages of this type of multi-layer cosmetics include:
Both the oil layer and the water layer after separation have almost transparent appearance, so it is difficult to understand at a glance that it is a multi-layer type. There is a problem that it becomes difficult to understand from.

[0004] As a method for solving the above-mentioned problems, a multi-layered cosmetic composition has been devised in which oil is collected at an upper portion while maintaining an emulsified state to form a cloudy emulsified layer.
In this case, it is not necessary to go through the delicate stage of re-coalescing the temporarily emulsified oil component, so that there is a possibility that the formulation has a wide range, and the appearance after two-layer separation,
Since the upper emulsified layer is cloudy, there is a merit that the two-layer type can be easily distinguished from the appearance.

[0005]

However, this type of multi-layer cosmetic has a serious problem that it takes a very long time to separate into two layers.

[0006] The speed of separation into two layers, that is, the speed at which emulsified particles dispersed uniformly float, depends on many factors, but is generally known as Stokes' law. Meanwhile, the moving speed of the emulsified particles is proportional to the square of the radius of the emulsified particles, is proportional to the difference in density between the oil component and the aqueous phase, and is inversely proportional to the viscosity of the aqueous phase. Here, when the density difference between the oil component and the aqueous phase is sufficient and the viscosity of the aqueous phase is sufficiently low, the speed of separation into two layers depends on the size of the emulsified particles. Specifically, when the time required for separation into two layers is roughly estimated, when the size of the emulsified particles is 1000 μm, the time required for separation is about several minutes, when it is 100 μm, it is about several hours, when it is 10 μm. Is calculated to take several days, and 1 μm takes several years.

[0007] Considering that ordinary cosmetics are used daily, it is ideal to return to a two-layered structure within a few hours after using the cosmetics. Not returning is considered a drawback for cosmetics. Therefore, the emulsified particles need to be prepared to have a size of about 100 μm or more. However, in general, emulsions that can be prepared with emulsions, creams and the like often have emulsified particles having a size of about 1 μm to about 10 μm, and it is actually very difficult to stably prepare emulsified particles having a size of 100 μm or more. difficult. For the preparation of an emulsion having large emulsified particles, a method called a dispersion method, in which the emulsified particles are finely divided by mechanical force, is used.In this method, the size of the emulsified particles is distributed. Of small emulsified particles. The small emulsified particles generated here have a very low floating speed as described above, so even after most of the large emulsified particles levitated to the upper part by standing, the small emulsified particles were still dispersed in the lower phase. Since it remains, the lower phase becomes turbid for a long time, and it is very difficult to form a two-layer structure with a beautiful appearance.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an oil-in-water emulsion type multi-layer cosmetic which has a short time for separating into a multi-layer and has a beautiful appearance.

[0009]

SUMMARY OF THE INVENTION In view of the above-mentioned situation, the inventors of the present invention have proposed a two-layer cosmetic composition in which oil collects in the upper part (or lower part) while maintaining an emulsified state to form a cloudy emulsified layer. As a result of intensive research to obtain a multi-layered cosmetic composition having a short time to separate into two layers and a beautiful appearance, polyethylene glycol having an average degree of polymerization of between 150 and 25,000, and a polyoxyethylene-based nonionic The present invention has been found that, by combining a surfactant and an oily raw material in a specific weight ratio and blending, a multi-layered cosmetic having a beautiful appearance can be obtained by separating into two layers in several hours to about one day. Was completed.

That is, the oil-in-water emulsion type multilayer cosmetic of the present invention contains polyethylene glycol having an average degree of polymerization of between 150 and 25,000, a polyoxyethylene-based nonionic surfactant, and an oily component. It is characterized by doing. Further, the oil-in-water emulsion type multilayer cosmetic of the present invention is characterized in that the composition has a viscosity at 30 ° C. of less than 50 mPa · s.

In the oil-in-water emulsion type multi-layer cosmetic of the present invention, the content of polyethylene glycol having an average degree of polymerization between 150 and 25000 is 0.5-20% by weight, and It is preferable that the content of the nonionic surfactant is 0.02 to 5% by weight.

In the oil-in-water emulsion type multilayer cosmetic of the present invention, the polyoxyethylene-based nonionic surfactant is preferably polyoxyethylene hydrogenated castor oil or polyoxyethylene dihydrocholesteryl ether. is there. Further, in the oil-in-water emulsion type multilayer cosmetic of the present invention, the content of the ionic surfactant is 0.001.
It is preferred that it is less than wt%.

Further, in the oil-in-water emulsion type multi-layer cosmetic of the present invention, the content of the electrolyte having no surface activity is 0.1%.
It is not less than 1% by weight. In the oil-in-water emulsion type multi-layer cosmetic, the weight ratio of the ionic surfactant to the weight of the entire composition is A, and the weight ratio of the electrolyte having no surfactant to the weight of the total composition is B. At this time, it is preferable that the concentration is such that log (B) / log (A) is 0.6 or less.

[0014]

Embodiments of the present invention will be described below in detail. The present invention relates to a liquid multi-layer cosmetic containing oil emulsified in an oil-in-water type, and more specifically, by shaking at the time of use, the emulsified oil is uniformly dispersed and becomes entirely cloudy, and after use, By leaving still
The emulsified oil collects at the top or bottom to form a layer,
At this time, the present invention relates to a multilayer cosmetic in which the formation speed of the layers is high and the appearance of each layer is beautiful. FIG. 1 shows a conceptual diagram of the present invention. That is, when the emulsified particles are usually small,
Although the rate of formation of the layer is slow, in the present invention, by mixing polyethylene glycol having a specific polymerization degree and a specific nonionic surfactant, fine emulsified particles are temporarily aggregated after dispersion to form an aggregate. By pseudo-enlarging the size of the emulsified particles to be formed, the ability to form a layer can be enhanced. That is, this enables layer separation in a sufficiently short time even if the emulsified particle diameter is usually less than 100 μm. In addition, very small emulsified particles can be collected by this aggregation action, and the transparency of the aqueous layer can be remarkably improved. It is also excellent in redispersibility after being divided into multiple layers and creaming.

First, each component of the present invention will be described.
You.Polyethylene glycol  Polyethylene glycol used in the present invention,
Having an average degree of polymerization of 150 or more and 25,000 or less,
In other words, the INCI name described later includes between PEG-150 and PEG-25M.
It is rare. The name of the cosmetic ruler is polyethylene
Recall 6000 to polyethylene glycol 1100
000, average molecular weight 6000
Between 110,000 and 110,000. Polypolymers of these specific polymerization degrees
Ethylene glycol aggregates the emulsified particles, and the composition
Excellent layer of multi-layer cosmetics because the viscosity of
It can contribute to resolution.

Here, polyethylene glycol will be described. Polyethylene glycol is a polymer of ethylene oxide and produces various products having different properties depending on the degree of polymerization. Therefore, polyethylene glycol is distinguished by the difference in the average degree of polymerization. US CTFA International Cosmetic Ingregient D
As shown in Table 1, the ictionary contains 1
Three types of polyethylene glycol have been described. IN
CI (International Nomenclature Cosmetic Ingredient)
In the nomenclature of, for example, those having an average degree of polymerization of 150
Named according to average degree of polymerization, such as -150. In the case where the average degree of polymerization is 1000 or more, for example, those having an average degree of polymerization of 2000 are named PEG-2M. Also, Japanese official regulations such as cosmetic rules and outer rules describe seven types corresponding to the present invention shown in Table 1, and are named like polyethylene glycol 6000 according to their average molecular weights. ing. In Table 1,
The INCI name of the polyethylene glycol corresponding to the present invention, and the corresponding cosmetic rule and outer rule name are described in parallel. In addition, since the degree of polymerization of each polyethylene glycol has a distribution, the distribution of the approximate molecular weight is also described in Table 1 if there is a literature value.

[0017]

[Table 1]  INCI name Cosmetic rule, outer rule name Average molecular weight  PEG-150 polyethylene glycol 6000 6000-7500 PEG-180 PEG-200 PEG-240 polyethylene glycol 11000 9300-12500 PEG-350 polyethylene glycol 20000 15500-25000 PEG-2M polyethylene glycol 100,000 8000-101000 PEG-5M PEG-7M PEG- 9M Polyethylene glycol 400,000 320,000 to 480,000 PEG-14M Polyethylene glycol 600,000 550,000 to 650,000 PEG-20M PEG-23M PEG-25M Polyethylene glycol 11,000,000 100,000 to 12,000,000  [Literature] A. Lourenco: Compt. Rend., 49, 619 (1959) Comment on Cosmetic Ingredients Second Edition (1984) Yakuji Nippo Co., Ltd. IV
(1989) Yakuji Nippo CTFA International Cosmetic Ingregient Dictionary
(1995)

In the present invention, the average degree of polymerization is 15
The content of polyethylene glycol, which is between 0 and 25000, is preferably in the range from 0.5 to 20% by weight. 0.5
If the amount is less than the weight%, it is not preferable because the layer separation ability is not sufficient and a multilayer having a beautiful appearance is not obtained. On the other hand, if the content exceeds 20% by weight, disadvantages such as reduced layer separation ability and sticky feeling in use may occur.

[0019]Polyoxyethylene-based nonionic surfactant
Agent  Polyoxyethylene nonionic surfactants are hydrophilic groups
Surfactant with a polyoxyethylene chain as
The base (lipophilic base) can have various structures
You. Some types of surface activity due to differences in the structure of this hydrophobic group
Agents are present, but in the present invention,
Has an oxyethylene chain and an ionic hydrophilic group
Any structure can be used if it has no structure
You. The following are specific examples. (After
The lower polyoxyethylene is abbreviated as POE. ) POE sorbitan fat
Fatty acid ester, POE sorbitol fatty acid ester, POE
Serine fatty acid ester, polyethylene glycol fatty acid
Ester, POE alkyl ether, POE phytosterol
Ether, POE phytostanol ether, POE cholester
Lyl ether, POE dihydrocholesteryl ether, POE
Polyoxypropylene alkyl ether, POE alkyl
Phenyl ether, POE castor oil, POE hydrogenated castor oil, PO
E-lanolin, POE lanolin alcohol, POE beeswax induction
Body, POE alkylamine, POE fatty acid amide, POE alkyl
Lephenylformaldehyde condensate, POE trimethylo
Lupropane fatty acid ester, POE / methylpolysiloxa
Copolymers, etc. can be used.
POE hydrogenated castor oil, POE dihydrocholesteryl ether
Is particularly preferred. The polyoxyethylene-based non-
Ionic surfactants further differ in the structure of the alkyl chain
And, due to the difference in the number of addition polymerization of polyoxyethylene chains,
There are things with all the different properties. In the present invention
Uses the above polyoxyethylene-based nonionic surfactant
Can be used alone or in combination of two or more
it can. In the present invention, the polyoxyethylene-based non-
By using ionic surfactant, transparency of aqueous phase
Excellent oil-in-water emulsion type multi-layer cosmetic
You.

In the present invention, the content of the polyoxyethylene-based nonionic surfactant is preferably in the range of 0.02 to 5% by weight. If the amount is less than 0.02% by weight, the emulsified state may not be sufficiently stabilized. On the other hand, if the content exceeds 5% by weight, on the contrary, the speed of phase separation may be lowered, and stickiness may be caused in terms of usability, which is not preferable.

[0021]Oily component  The oil component used in the present invention is usually used in cosmetics.
Use any oily component that can be used.
Can be. Olive oil etc.
Natural vegetable oils, wax esters such as carnauba wax
, Squalane, liquid paraffin, vaseline, paraffin
Hydrocarbons, such as acetylene, and estyl such as cetyl 2-ethylhexanoate.
Silicone oils such as tellur oils and methylpolysiloxane,
Examples include higher fatty acids and higher alcohols. This
These oily components may be used alone or in combination of two or more.
Can be used.

[0022]Composition viscosity  The viscosity of the oil-in-water emulsion type multilayer cosmetic of the present invention is 30 ° C.
In this case, the pressure is preferably less than 50 mPa · s. this
At the above viscosity, it does not separate into multiple layers,
It is not preferable because the release speed may be extremely slow.
No.

[0023]Ionic surfactant  In the present invention, the composition contains an ionic surfactant.
Preferably, the amount is less than 0.001% by weight.
When the content is 0.001% by weight or more, the phase separation ability and the aqueous phase
It is not preferable because transparency may be impaired. However
However, if it contains an electrolyte that does not have surface activity
Not as long as the.

[0024]Electrolyte without surface activity  Further, in the present invention, the ionic surfactant is 0.0%
Even if it contains more than 01% by weight,
0.1% by weight of electrolyte
Thus, the present invention can be achieved.

The non-surfactant electrolyte used in the present invention is a substance which dissolves in water to form charged ions in a solution and does not form an aggregate such as micelle in an aqueous solution. Or a substance that does not specifically adsorb to the water-oil interface in the emulsion. Many of them are salts formed by a combination of an acid and a base. Specific acids to be combined include hydrochloride, phosphate, metaphosphate,
Polyphosphate, sulfate, sulfite, borate, carbonate,
Nitrate, citrate, lactate, acetate, malate, tartrate, succinate, acidic amino acid salt, salicylate,
Benzoates, sulfocarbanoates, edetates, ascorbates, gluconates, pyrrolidonecarboxylates, and the like, and specific bases include sodium salts, potassium salts, magnesium salts, calcium salts, Examples include triethanolamine salts, aminomethylpropanol salts, basic amino acid salts, and the like, and these acids and bases can be arbitrarily combined. In addition, amphoteric substances such as amino acids and betaine can be used as the substance having a charge alone in an aqueous solution instead of a salt.

The relationship between the concentration of the ionic surfactant and the minimum required concentration of the electrolyte having no surface activity is as follows. That is, assuming that the weight ratio of the ionic surfactant to the weight of the total composition is A and the minimum required concentration of the weight ratio of the electrolyte having no surface activity to the weight of the total composition is B, the ionic surfactant is composed of When it is contained in a substance, the concentration is preferably such that log (B) / log (A) is 0.6 or less. If the above value is greater than 0.6,
This is not preferred because the transparency of the aqueous layer and the excellent layer forming ability may be impaired.

[0027]Other ingredients  In the oil-in-water emulsion type multilayer cosmetic according to the present invention, the above-mentioned
In addition to the essential components, unless the effects of the present invention are impaired
Ingredients commonly included in cosmetics are added as needed
be able to. These components include ethanol,
Lower alcohols such as isopropyl alcohol, glycerin
Propylene glycol, dipropylene glycol,
1,3-butanediol, sorbitol, maltitol
Polyhydric alcohols such as talc, kaolin, titanium oxide
, Silicic anhydride, powder such as cellulose powder, polyvinyl
Pyrrolidone, polyvinyl acetate, carboxymethyl cellulose
Water-soluble polymers such as glucose and xanthan gum, anionic
Surfactants, amphoteric surfactants, preservatives, bactericides, UV absorbers
Includes sorbents, chelating agents, antioxidants, fragrances, etc.
You.

[0028]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, the blending amount is% by weight, and the viscosity of each composition at 30 ° C. is less than 50 mPa · s unless otherwise specified. Prior to the examples, tests performed during the development process of the present invention will be described below.

[0029]Selection of aggregation components  The present inventors first, an appropriate amount of a cloudy lotion of the following formulation
Add various components and observe the state of emulsified particles with a microscope
In addition, by observing the appearance of the lotion,
Screening, a component capable of aggregating emulsified particles
Performed. Table 2 shows the results.

<Preparation of cloudy lotion> Methyl polysiloxane 1% by weight POE (60) hydrogenated castor oil 0.5 1,3-butylene glycol 5 Preservatives Appropriate amount Purified water residue

[Production Method] Using a high-capacity dispersing apparatus, emulsification is carried out to a particle size of about 1 to 5 μm.

[0032]

[Table 2]  Ingredients Blended amount Aggregation of emulsified particles Presence of creaming (%)  None---PEG-8 (* 1) 1--PEG-350 (* 2) 1 ○ ○ Polyarginine 1--Polyvinyl alcohol 1--Trimethylglycine 1--  * 1: Polyethylene glycol 400 (average degree of polymerization 8) * 2: Polyethylene glycol 20000 (average degree of polymerization 350)

From the results in Table 2, it can be seen that when polyethylene glycol (PEG-350) was added, aggregation of the emulsified particles was observed and creaming of the emulsified particles occurred. The aggregate of the emulsified particles formed here did not change with time and did not coalesce. The aggregate was dispersed when stirred, and again aggregated in a short time when allowed to stand.

Next, the present inventors conducted further studies in order to complete an oil-in-water emulsion type multilayer cosmetic. Less than,
The evaluation method used in each example will be described.

[Measurement of two-layer separation speed] Glass sedimentation tube (capacity 100 ml, outer diameter 30 mm, height 250 mm, with 100 ml scale)
Put 100 ml of the sample well dispersed in the flask, place in a thermostat at 30 ° C., and let it stand at 30 ° C. When the temperature reaches 30 ° C, remove the sedimentation tube.
Invert about 25 times for 1 minute to disperse the contents well,
Leave in 0 ° C constant temperature bath. Twenty-four hours after that, the volume of the lower layer is measured in a state of separation into two layers. The evaluation of the bilayer separation rate also depends on the lower volume when the equilibrium state is reached.
If the time value is half or more than 40 ml, it can be determined that the separation speed is sufficiently fast, and if it is less than 10 ml, it is determined that the separation speed is low.

[Aqueous layer transparency test] Glass sedimentation tube (capacity 100 ml, outer diameter 30 mm, height 250 mm, 100 ml scale)
100 ml of the sample well dispersed in the flask is left in a thermostat at 30 ° C. for 24 hours to separate into two layers. The sedimentation tube was placed in front of the black plate, and the transparency of the aqueous layer was observed with the naked eye, and judged based on the following criteria. ：: almost transparent △: slightly transparent but slightly cloudy ×: cloudy and almost transparent

[Usability test] About 1 ml of a sample was applied to the face of 10 female panels in their 20s and 30s, and a questionnaire on usability was taken. The evaluation was made according to the following criteria. ○: Two or less panelists answered “sticky” △: Three or more panelists answered “sticky” ×: Six or more panelists answered “sticky” Was

[Emulsification Stability Test] A 50 ml sample was placed in a glass tube with a screw cap having a capacity of 100 ml, and 300 ml per minute.
Repeat shaking at a rate of 20 times and continue for 20 minutes. Thereafter, a sample was taken, the size of the emulsified particles was measured with a microscope, and separation of oil components was observed, and evaluated according to the following criteria. ：: No change in the size of the emulsified particles, and no separation of oil was observed. Δ: Some of the emulsified particles were separated, but no separation of oil was observed. Is recognized

The present inventors have found that by using polyethylene glycol having a certain degree of polymerization and a specific nonionic surfactant, an excellent oil-in-water emulsion type multilayer cosmetic can be obtained. Then, the following test was conducted to complete the present invention as an actual cosmetic. A multi-layered cosmetic having the composition shown in the following Tables 3 to 6 was prepared, and the two-layer separation speed was measured, and the transparency test, usability test, and stability test of the aqueous layer (lower layer) after separation were performed. Was.

[0040]Examination of the degree of polymerization of polyethylene glycol  Next, the present inventors determined the degree of polymerization of polyethylene glycol.
Was examined using the compositions shown in the following table.

[0041]

[Table 3]  Example 1 Example 2 Example 3 Example 1 Example 2 Example 3 Example 4  PEG-32 (* 1) 10 − − − − − − − PEG-75 (* 2) − 5 10 − − − − PEG-150 (* 3) − − − 5 − − − PEG-240 (* 4) − − − − 5 − − PEG-25M (* 5) − − − − − 2 − PEG-45M (* 6) − − − − − − −2 POE (60) hydrogenated castor oil 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Liquid paraffin 5 5 5 5 5 5 5 Glycerin 5 5 5 5 5 5 5 Monosodium phosphate 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Preservatives qs qq qq qq qq qq qq Purified water Residue Residue Residue Residue Residue  Two-layer separation speed (ml) 0 0 5 75 75 55 30 Aqueous layer transparency × × △ ○ ○ ○ ○ Usability ○ ○ ○ ○ ○ △ × Stability ○ ○ ○ ○ ○ ○ ○  * 1: Polyethylene glycol 1540 (average degree of polymerization 32) * 2: Polyethylene glycol 4000 (average degree of polymerization 75) * 3: Polyethylene glycol 6000 (average degree of polymerization 150) * 4: Polyethylene glycol 11000 (average degree of polymerization 240) * 5 : Polyethylene glycol 1100000 (average degree of polymerization 25,000) * 6: polyethylene glycol 2500000 (average degree of polymerization 45000)

As is clear from Table 3, the multilayer cosmetics of the present invention (Examples 1 to 3) have a high two-layer separation speed and are excellent in the appearance of the two layers. If the average degree of polymerization of polyethylene glycol is less than 150 (Comparative Examples 1 to 3), the lower layer volume after 24 hours is less than 10 ml, the separation speed is low, and satisfactory results cannot be obtained. When the average degree of polymerization of polyethylene glycol exceeds 25,000,
(Comparative Example 4) Satisfactory results cannot be obtained because the usability is sticky.

[0043]Formulation of polyethylene glycol with specific polymerization degree
Consider quantity  Next, the present inventors, polyethylene glycol specific polymerization degree
Investigation of the blending amount of the resin was carried out using the compositions shown in the following table.

[0044]

[Table 4]  Test example Test example Test example Test example Test example Test example Test example Test example Component name 1 2 3 4 5 6 7  PEG-350 0 0.1 0.5 1 5 20 30 POE (60) hydrogenated castor oil 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Liquid paraffin 5 5 5 5 5 5 5 Glycerin 5 5 5 5 5 5 5 5 Monosodium phosphate 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Preservatives qs qs qq qq qq qq qs Purified water residue residue residue residue residue residue residue residue  Bilayer separation speed (ml) 0 0 70 75 75 75 50 Transparency of aqueous layer × × △ ○ ○ ○ ○ Usability ○ ○ ○ ○ ○ △ × Stability ○ ○ ○ ○ ○ ○ ○

As is apparent from Table 4, in the water-in-oil emulsion type multi-layer cosmetic composition of the present invention, the amount of polyethylene glycol having an average degree of polymerization between 150 and 25,000 is less than 0.5% by weight. If less (Test Examples 1 and 2)
When the separation speed is low and the amount exceeds 20% by weight (Test Example 7), the usability becomes poor due to stickiness, so the amount of the specific polymerization degree polyethylene glycol is 0.5% by weight or more.
Preferably it is 20% by weight.

[0046]Examination of the type of surfactant  Next, the present inventors examined the types of surfactants in the following table.
Of the composition.

[0047]

[Table 5]  Comparative Comparison Performed Performed Performed Performed Ingredient Name Example 5 Example 6 Example 4 Example 5 Example 6 Example 7 Example 8  PEG-350 5 5 5 5 5 5 5 Sodium stearoyl quartamate 0.2 − − − − − − − sucrose stearate − 0.2 − − − − − POE (30) Scihuman cholesteryl ether − − 0.2 − − − − POE (60) Querceryl monoisostearate---0.2---POE (20) sorbitan monooleate----0.2--POE (10) monoisostearate-----0.2-POE (30) hexenyl ether-- − − − − 0.2 Liquid paraffin 5 5 5 5 5 5 5 Glycerin 5 5 5 5 5 5 5 Monosodium phosphate 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Preservatives Appropriate amount Appropriate amount Appropriate amount Appropriate amount Appropriate amount Purified water Residue Residue Residue Residue Residue  Two-layer separation speed (ml) 0 10 75 75 75 75 70 Transparency of aqueous layer × × ○ ○ ○ ○ ○ Usability ○ ○ ○ ○ ○ ○ ○ Stability △ △ ○ △ △ △ △

As is clear from Table 5, the multilayer cosmetic of the present invention has a high two-layer separation speed and is excellent in the appearance of two layers. When an anionic surfactant was used (Comparative Example 5) or when a nonionic surfactant other than polyoxyethylene was used (Comparative Example 6), the two-layer separation speed was low, and both were satisfactory. No result. Among polyoxyethylene-based nonionic surfactants, when polyoxyethylene hydrogenated castor oil was used (see Test Example 5 in Table 4) and when polyoxyethylene dihydrocholesteryl ether was used (Example 4), The stability is particularly good, and among them, these are particularly preferable.

[0049]Polyoxyethylene-based nonionic surfactant
Examination of compounding amount of agent  Next, the present inventors, polyoxyethylene non-ionic
Examination of the blending amount of the ionic surfactant using the composition shown in the table below
went.

[0050]

[Table 6]  Test example Test example Test example Test example Test example Component name 8 9 10 11 12  PEG-350 2 2 2 2 2 POE (60) hydrogenated castor oil 0.01 0.02 1 5 10 Liquid paraffin 5 5 5 5 5 Glycerin 5 5 5 5 5 Monosodium phosphate 0.2 0.2 0.2 0.2 0.2 Preservatives Qs Qs Qs Qs Qs Purification Water residue residue residue residue residue residue  Two-layer separation speed (ml) 80 80 75 40 10 Transparency of aqueous layer △ ○ ○ ○ ○ Usability ○ ○ ○ ○ × Stability × △ ○ ○ ○

As apparent from Table 6, in the multilayer cosmetic of the present invention, when the blending amount of the polyoxyethylene-based nonionic surfactant is less than 0.02% by weight (Test Example 8). On the other hand, when stable emulsification cannot be maintained, and when the blending amount of the polyoxyethylene-based nonionic surfactant is more than 5% by weight (Test Example 12), the two-layer separation speed is low and the stickiness is poor. Since it becomes worse, the blending amount of the polyoxyethylene-based nonionic surfactant is preferably between 0.02 and 5% by weight.

[0052]Relationship between viscosity and separation speed  Preparation of a multi-layer cosmetic having the composition shown in Table 7 below
The viscosity and two-layer separation speed were measured.

[0053]

[Table 7]  Test example Test example Test example Test example Test example Test example Component name 13 14 15 16 17 18  PEG-350 2 2 2 2 2 2 POE (60) hydrogenated castor oil 0.2 0.2 0.2 0.2 0.2 0.2 Methyl polysiloxane 5 5 5 5 5 5 Ethanol 5 5 5 5 5 5 1,3-butylene glycol 2 2 2 2 2 2 Monosodium phosphate 0.2 0.2 0.2 0.2 0.2 0.2 Xanthan gum 0 0.02 0.05 0.1 0.15 0.2 Preservatives qs qs qq qq qs qq Purified water residue residue residue residue residue residue  Viscosity (mPa · s / 30 ° C) 6 10 18 45 116 304 Two-layer separation speed (ml) 80 75 50 12 00

Table 7 shows the results of the two-layer separation speed when the viscosity of the composition was changed by changing the content of xanthan gum. From the results, it was found that the viscosity at 30 ° C. of the composition was 5%.
In the case of less than 0 mPa · s (Test Examples 13 to 16), a sufficient bilayer separation speed is obtained, but in the case of 50 mPa · s or more (Test Example 1)
7, 18) It can be seen that the two-layer separation speed is low and the effect of the present invention is not sufficiently exhibited. That is, 30 ° C. of the composition
It can be seen that a viscosity of less than 50 mPa · s is one of the preferred conditions of the present invention.

Next, the present inventors have developed an anionic surfactant.
To what extent ionic surfactants such as surfactants
Check if it can be used for oil-in-water emulsion type multi-layer cosmetics
Debated.Relationship between the presence or absence of ionic surfactant and the state of two-layer separation  Prepare an oil-in-water emulsion type multi-layer cosmetic comprising the following composition,
The concentration of the ionic surfactant in the composition (X in the following formulation)
And the concentration of the electrolyte (indicated by Y in the following formulation)
Each of the multi-layer cosmetics was prepared, and for them,
Two-layer separation state after standing for 24 hours and water layer after separation
The transparency of the (lower layer) was observed. Table 8 shows the results.

[Formulation] (1) PEG-350 2% by weight (2) Methylpolysiloxane 2 (3) POE (30) dihydrocholesteryl ether 0.2 (4) Stearoyl glutamate monosodium X (5) Monosodium phosphate Y (6) Ethanol 2 (7) 1,3-butylene glycol 2 (8) Methyl paraben 0.2 (9) Purified water residue

[Evaluation Criteria] ○: Separated into two layers and the lower layer is almost completely transparent. △: Separated into two layers and the lower layer is slightly white and transparent. △: Separated into two layers and the lower layer is slightly opaque and translucent. △ ×: The whole is uniformly turbid, and a part of the oil is concentrated on the upper part. ×: The whole is uniformly turbid.

[0058]

[Table 8]  Stearoyl glutamate monosodium concentration (X) 0 0.001 0.005 0.02 0.1  0 △ × × × × 0.001 ○ △ × × × × 0.005 ○ × × × × Phosphoric acid 0.01 ○ × × × × Monosodium 0.02 ○ × × × × Concentration 0.05 ○ × × × × (Y) 0.1 ○ ○ × × × 0.2 ○ ○ ○ △ × × 0.5 ○ ○ ○ ○ △ 1 ○ ○ ○ ○ △ 2 ○ ○ ○ ○ ○ △

As apparent from Table 8, when the concentration of monosodium stearoyl glutamate, which is an ionic surfactant, is less than 0.001% (the leftmost column in Table 8), a two-layer appearance is obtained. You can see that. In the case of an ordinary general emulsified composition, an ionic surfactant such as a fatty acid soap is often used as an emulsifier, but in the present invention, only a nonionic surfactant is used as an emulsifier, and an ionic surfactant is used. It is one of the more preferable conditions of the present invention that no agent is contained.

In addition, 0.001% of ionic surfactant
Even in the case of containing the above (the second and subsequent columns from the left of Table 8), a two-layer appearance can be obtained by containing 0.1% or more of an electrolyte having no surfactant. .

In this case, it was found from the experiment in Table 8 that there is a certain relationship between the concentration of the ionic surfactant and the minimum required concentration of the electrolyte having no surfactant. Is derived. The weight ratio of the ionic surfactant to the weight of the whole composition is A (corresponding to X / 100), and the minimum required concentration of the weight ratio of the electrolyte having no surface activity to the weight of the whole composition is B (Y / 100). Table 9 shows that the relationship of log (B) / log (A) = 0.6 holds with respect to the minimum required B value. That is, when an ionic surfactant is contained in the composition, log (B)
One of the more preferred conditions of the present invention is a concentration at which / log (A) is 0.6 or less.

[0062]

[Table 9]  AB log (A) log (B) log (B) / log (A)  0.00001 0.001 -5.00 -3.00 0.60 0.00005 0.002 -4.30 -2.70 0.63 0.0002 0.005 -3.70 -2.30 0.62 0.001 0.02 -3.00 -1.70 0.57

Hereinafter, examples of the present invention will be further described. <Example 9> An oil-in-water emulsion type multilayer cosmetic having the following composition was prepared. [Formulation] (1) PEG-6 3% by weight (2) PEG-323 (3) PEG-350 2 (polyethylene glycol 20000, average degree of polymerization 350) (4) POE (30) dihydrocholesteryl ether 0.3 ( 5) Methylpolysiloxane 5 (6) Citric acid 0.1 (7) Sodium citrate 0.3 (8) Methylcellulose 0.1 (9) Sodium carboxymethylcellulose 0.1 (10) Ethanol 10 (11) Preservative appropriate amount (12) Appropriate amount of fragrance (13) Purified water residue [Production method] (1) to (3) and (6) to (9) are added and dissolved in (13). Next, (4), (11) and (12) dissolved in (10) are mixed. Next, (5) is added and emulsification is performed by vigorous stirring. A multi-layer cosmetic having a high two-layer separation speed and good appearance and usability was obtained.

Example 10 An oil-in-water emulsion type multilayer cosmetic having the following composition was prepared. [Prescription] (1) 1,3-butylene glycol 10% by weight (2) glycerin 5 (3) PEG-2M 2 (polyethylene glycol 100000, average degree of polymerization 2000) (4) POE (60) hydrogenated castor oil 0.4 (5) POE / methylpolysiloxane copolymer 0.1 (6) Methylpolysiloxane 2 (7) Decamethylcyclopentasiloxane 2 (8) Monosodium phosphate 0.1 (9) Disodium phosphate 0.1 (10) Sodium alginate 0.2 (11) Trisodium EDTA 0.1 (12) Ethanol 5 (13) Appropriate amount of preservative (14) Appropriate amount of perfume (15) Residual water Residue [Production method] According to Example 9. A multi-layer cosmetic having a high two-layer separation speed and good appearance and usability was obtained.

Example 11 An oil-in-water emulsion type multilayer cosmetic having the following composition was prepared. [Prescription] (1) PEG-350 3% by weight (polyethylene glycol 20000, average degree of polymerization 350) (2) glycerin 1 (3) POE (60) hydrogenated castor oil 0.3 (4) methylphenylpolysiloxane 5 (5) ) Talc 2 (6) Citric acid 0.1 (7) Sodium citrate 0.3 (8) Ethanol 25 (9) Preservative proper amount (10) Flavor proper amount (11) Purified water residue [Production method] According to Example 9 . A multi-layer cosmetic in which the cloudy oil layer settles down was obtained, and a two-layer separation speed was high, and a multi-layer cosmetic having good appearance and usability was obtained.

[0066]

EFFECT OF THE INVENTION The oil-in-water emulsion type multilayer cosmetic of the present invention comprises:
Since it contains polyethylene glycol having an average degree of polymerization of 150 to 25,000, a polyoxyethylene-based nonionic surfactant, and an oily component, the emulsified oil component is uniformly dispersed by shaking at the time of use. The whole becomes cloudy.After use, the emulsified oil collects on the upper or lower part to form a layer.The layer formation speed at this time is high, and the appearance of each layer is good. It can be a cosmetic.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a multilayer separation mechanism of an oil-in-water emulsion type multilayer cosmetic according to the present invention.

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Claims (7)

[Claims] 1. An oil-in-water emulsion type multi-layer cosmetic comprising polyethylene glycol having an average degree of polymerization of between 150 and 25,000, a polyoxyethylene-based nonionic surfactant, and an oily component. Fees. 2. The oil-in-water emulsion type multilayer cosmetic according to claim 1, wherein the viscosity of the composition at 30 ° C. is 50 mPa · s.
The oil-in-water emulsification type multilayer cosmetic characterized by being less than the following. 3. The oil-in-water emulsion type multilayer cosmetic according to claim 1, wherein the average degree of polymerization is 150 to 25.
Water having a content of polyethylene glycol of between 0.5 and 000, and a content of polyoxyethylene-based nonionic surfactant of 0.02 to 5% by weight. Oil emulsified multilayer cosmetic. 4. The oil-in-water emulsion type multi-layer cosmetic according to claim 1, wherein the polyoxyethylene nonionic surfactant is polyoxyethylene hydrogenated castor oil or polyoxyethylene dihydrocholesteryl ether. An oil-in-water emulsion type multilayer cosmetic characterized by the following. 5. The oil-in-water emulsion type emulsion according to claim 1, wherein the content of the ionic surfactant is less than 0.001% by weight. Multi-layer cosmetic. 6. The oil-in-water emulsification according to claim 1, wherein the content of the electrolyte having no surface activity is 0.1% by weight or more. Type multilayer cosmetics. 7. The oil-in-water emulsified multilayer cosmetic according to claim 6, wherein the weight ratio of the ionic surfactant to the weight of the total composition is A, and the weight of the electrolyte having no surfactant is based on the weight of the total composition. When the weight ratio is B, log (B) / log
An oil-in-water emulsion type multilayer cosmetic, wherein (A) has a concentration of 0.6 or less.