JPH03178331A - Microemulsion composition - Google Patents

Abstract

PURPOSE:To enhance the safety to the skin and storage stability by preparing a microemulsion composition containing an oily substance liquid at room temp., a nonionic surfactant having a specific HLB value, vitamin E and water in respective specific amounts. CONSTITUTION:A preparatory emulsion is prepared by mixing at least one kind of an oily substance (a) liquid at room temp., at least one kind of a nonionic surfactant (b) having an HLB value of 7.0-16.0, at least one kind of vitamin E or its derivative (c) and water so that the wt. ratio of (a):(b):(c) becomes a range of 1:0.5-5.0:0.01-0.5. The preparatory emulsions are allowed to collide with each other, for example, by adapting an injection means such as a nozzle to prepare a microemulsion composition having an average particle size of 10-200nm.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a liquid oily substance having a specific ratio described below.

Regarding a finely divided emulsion composition prepared by colliding a pre-emulsion containing a specific nonionic surfactant, vitamin E or a vitamin E derivative, and water, more specifically, it can be used in the fields of cosmetics, pharmaceuticals, etc. This invention relates to a micronized emulsion compound with excellent skin safety, sensory properties, and storage stability.

[Prior art and problems to be solved by the invention] In the development of conventionally known fine emulsions, in order to make the emulsion particles fine and obtain a transparent composition, it is generally necessary to use a large amount of surfactant. When applied as cosmetics, there are problems such as a decrease in organoleptic properties and skin safety due to the large amount of surfactant.

For example, if we take a general transparent lotion as an example, the amount of surfactant required for the oily acid content is 5 to 2.
0 (@ quantity.

However, Japanese Patent Application Publication No. 52-151676,
By using the emulsification and dispersion method described in Japanese Patent Publication No. 15005, it is possible to prepare a fine emulsion containing many fake oily components using a small amount of surfactant. The emulsification and dispersion method described in these is a known high-pressure emulsification method,
The emulsions are injected from at least one nozzle and the emulsions are made to collide with each other, or the perforated material is made to collide with the wall of the vessel, thereby making it fine. As 62N to which such an emulsification dispersion method is applied, for example,
Micro-fluidizer
(manufactured by S company). This has made it possible, for example, to prepare a transparent lotion that contains a large amount of oily ingredients, has a good feel, and is highly safe for the skin.

However, the micronized emulsion thus obtained is not necessarily stable, and has the problem that the particles coalesce or separate when heated or over time, making it impossible to maintain the micronized state.

For example, by combining an appropriate nonionic surfactant with an oily component and treating the resulting pre-emulsion using the emulsification and dispersion method described above, you can easily create a transparent or translucent fine emulsion! It can be made from Il. Furthermore, it is sufficient to use the nonionic surfactant in an amount of 0.5 to 2.0 times the amount of the oily component. However, by leaving the fine emulsion at 45°C,
Weeks, or as early as the next day, it becomes cloudy or separates.

That is, although this finely divided emulsion has excellent organoleptic properties and skin safety, it has the problem of poor storage stability.

Using the above-mentioned emulsification and dispersion method, we prepared a finely divided emulsion containing a large amount of oily components with a small amount of surfactant, which has excellent skin safety, sensory properties, and storage stability. As a result, vitamin E or a vitamin E derivative of a specified star is added as an emulsification activation aid to the emulsified tetraacid acid, which is a combination of an oily substance that is liquid at room temperature and a nonionic surfactant, which is used in ordinary fine emulsions. By doing so, it was surprisingly discovered that the storage stability of the finely divided emulsion was significantly improved compared to a finely divided emulsion that did not contain these ingredients, and the present invention was completed.

The present invention comprises (al) at least one oily substance that is liquid at room temperature, at least one nonionic surfactant having an ibl o LB value in the range of O-16.0, and fcl vitamin E or containing at least one vitamin E derivative and FDL water, and the above +a): (bl
: The weight ratio of ICL! (0,5~5.0):
(0.01 to 0.5), with an average particle size of 10 to 200 nm, obtained by colliding preemulsions with each other or colliding the preemulsions with a wall.
It is a micronized emulsion m-acid characterized by the following.

The configuration of the present invention will be explained in detail below.

The oily substances used in the present invention are oils that are liquid at room temperature, such as liquid paraffin, squalane, and liquid synthetic esters (isopropyl myristate, isopropyl palmitate, myristic acid). octyldodecyl, etc.), vegetable oils (olive oil, soybean oil, rice bran oil, cottonseed yuzu, etc.), methylphenylpolysiloxane, and the like. However, it is not limited to these.

Liquid oily substances may be used alone or in combination of two or more.

The nonionic surfactant used in the present invention is normally used as a raw material for cosmetics and the like, and is not particularly limited. For example, POE sorbitan fatty acid esters such as polyoxyethylene (hereinafter referred to as POE) sorbitan monooleate, POE sorbitan monostearate, POE sorbitan trioleate, POE
PO such as sorbitol monooleate, POE sorbitol pentaoleate, POE sorbitol monostearate, etc.
POE such as E sorbitol fatty acid ester ti, POE glycerin monostearate, POE glycerin monoisostearate, POE glycerin triisostearate, etc.
Glycerin fatty acid esters such as glycerin fatty acid esters, glyceryl monostearate, glyceryl monoisostearate, etc.'1. POE monooleate 1-, POE
POE fatty acid esters such as distearate and POE dioleate, POE oleyl ether, POE stearyl ether, and POE behenyl ether.

POE2. -Octyldodecyl ether, POE2-hexyldecyl ether, POE2-hebutyl undecyl ether, POE2-decyltetradecyl ether, PO
POE alkyl ethers such as E2-decylpentadecyl ether and POE cholestanol ether, POE alkyl phenyl ethers such as POE nonylphenyl ether, and POE-POP block copolymers.

POE-POP alkyl ethers such as POE/POP cetyl ether, POE-POE2-decyltetradecyl ether, POE/POP hydrogenated lanolin, POE castor oil or hydrogenated castor oil derivatives such as POE castor oil,
Examples include poEs wax and lanolin derivatives such as POE sorbitol beeswax, sugar esters such as sila sugar oleic acid monoester, polyglycerin monoalkyl esters and monoalkyl ethers.

Among these nonionic surfactants, those with an HLB value of 7.
One type or a combination of two or more types in the range of 0 to 16.0 may be used.

Examples of combinations of these liquid oily substances and nonionic surfactants suitable for emulsifying and dispersing them include the following.

Liquid oily substance Nonionic surfactant Liquid paraffin Polyoxyethylene sorbitan monostearate (20E, ○,) Polyoxyethylene sorbitan tristearate (20E, O,) Polyoxyethylene glycerin monostearate (5E, O, ) Squalane polyoxyethylene sorbitan trioleate (20E, O,) Polyoxyethylene sorbitan monooleate (6E, O,) Polyoxyethylene monostearate (IOE, O-) Octyldodecyl myristate polyoxyethylene monolaurate ( 10E, O,) Polyoxyethylene sorbittetraoleate (40E, O, y Polyoxyethylene cetyl ether (IOE, O,) Olive oil polyoxyethylene oleyl ether (7E, ○,) Polyoxyethylene behenyl ether (10E, O, ,) Polyoxyethylene hydrogenated castor oil (20E, O,) Methylphenylpolysiloxane polyoxyethylene sorbitan trioleate (20E, O,) Polyoxyethylene sorbitan monooleate (6E, O,) Polyoxyethylene hydrogenated castor oil ( 20E, Q,) Of course, the combination is not limited to these.

The vitamin E or vitamin E derivative used in the present invention is a known substance, such as vitamin E virane-1 E acetate and vitamin E derivative ne-1.

Examples include vitamin E succinate, vitamin E lyl-tobital E orotate, and the like. Vitamin E is α-
Refers to tocopherol, β-tocopherol, γ-1 copherol, δ-), copherol, etc., or a mixture thereof.

In the present invention, these vitamin E or vitamin E
At least one of m6 bodies is used.

The amount of liquid oily substance used in the present invention is as follows:
Preferably it is 0.1 to 30% by weight. Further, the amount of the nonionic surfactant to be blended is determined by the ratio to the liquid oily substance, and the ratio is 10.5 to 1:5, preferably 1:1 to 1:3. If the ratio of nonionic surfactant is less than 1:0.5, no finely divided emulsion will be produced, while if it exceeds 1:5, the skin safety and sensory properties will be poor.

Also, regarding the amount of vitamin E or its derivatives,
Similarly, it is determined by the ratio with the liquid oil substance, and the ratio is 1:0.01 to 1:O,S, preferably 1:0.05 to 1:0.2. If the ratio of vitamin E or its derivative is less than 1=0.01, it is not sufficient to achieve the desired effect of the present invention, but even if it exceeds 1:0.5,
It is not possible to expect an improvement in effectiveness commensurate with the increase.

At such a ratio, the pre-emulsions obtained by a normal emulsification method are made to collide with each other or the pre-emulsions are made to collide with a wall to make the emulsified particles finer, and further, as necessary, to obtain a desired average particle size. The average grain size of the fine emulsion in the present invention is 10 to 200 nm, which is not preferable because the appearance will be poor if it is outside this range.

In the present invention, as a means for making the above-mentioned preliminary emulsion fine, there is, for example, injection using a nozzle. In this case, the injection pressure should be set to 300 to 1000 kg/cm, for example.
, By setting the temperature in the range of 5 to 40℃,
The desired micronized emulsion described above can be obtained. However, this varies depending on the device and is not particularly limited.

The fine emulsion composition of the present invention is characterized by being able to incorporate a large amount of oily ingredients with a much smaller amount of nonionic surfactant than conventional solubilized systems, and having excellent organoleptic properties and skin safety. It also has excellent appearance and storage stability.

In addition to the above-mentioned essential ingredients, the micronized emulsion of the present invention also contains five pigments, fragrances, preservatives, pigments, antioxidants, thickeners,
Heat insulating agents, ultraviolet absorbers, chelating agents, other oils, surfactants, active aids, and the like can be blended as appropriate within the range that achieves the object of the present invention.

The micronized emulsion composition of the present invention can be used, for example, in lotions, hair tonics, and hair oils.

It can be used in products such as cleansing oils, aerosol products, and pharmaceutical liquids.

〔Example〕

Hereinafter, the present invention will be described in detail based on Examples and Comparative Examples.

The test methods for skin safety, sensory properties, and storage stability described in the Examples are as follows.

(1) Skin safety test Samples o and o s were applied to the skin on the side of the forearm layer of 25 subjects.
g was applied for 24 hours as an occlusive patch using a circular lint cloth with a diameter of 1.0 cm.
The skin condition of 25 subjects was evaluated for each sample according to the following criteria.

The evaluation results were determined based on the stronger reaction between 1 hour and 24 hours after removal of the bandage, and expressed as the number of people who rated (±) or higher.

Judgment Criteria (2) Sensory Characteristics Evaluation After 20 test subjects used the sample for 10 days, the characteristics of the sample were evaluated.

The test results were ``no sticky or slimy feeling''
, the number of people who answered that it blends well with the skin and that it has a desirable oily feel.

(3) Storage stability test After storing the sample in a constant temperature room at 45℃ for two weeks, observe the appearance of the sample. If no abnormality is observed (the appearance is transparent or translucent), it is considered good. If this was observed (oil separated, cloudy, etc.), it was judged as defective.

In addition, those that were already cloudy at the time of preparation were marked as "-".

(4) Measurement of average particle size Particle size distribution analyzer submicron sizer B1-90 (BROOK-HAVEN) applying photon correlation spectroscopy
INsTRUMENTs C0R-PO[? ATI
(manufactured by ON), the average particle diameter was measured immediately after preparation.

Examples 1-11. Comparative Examples 1 to 53! A transparent lotion was prepared according to the composition shown below, and the various tests described above were conducted. The results are shown in Table 1.

(1) Precautions (2) Preparation method Component (C) was uniformly dissolved in component (A) at room temperature or with salt, and component (B) was added thereto and mixed uniformly. Component (D) was successively added thereto and mixed and stirred to form a preliminary emulsion.

This is carried out using a microfluidizer (Microfluidizer).
(manufactured by DICS), 700 kg/cm”, 3Q
(3) Characteristics As shown in Table 1, Examples 1 to 8, which are micronized emulsions of the present invention, are finer than Comparative Examples 1 to 15. In all aspects of sex testing, sensory evaluation, and storage stability testing,
Good evaluations were obtained.

In particular, it was clearly observed that the storage stability of the micronized emulsion was significantly improved by adding a small amount of Vita Straw E or a vitamin E derivative.

〔Effect of the invention〕

As described above, the micronized emulsion composition of the present invention has been shown to have high skin safety, excellent sensory properties, and excellent storage stability.

Claims (1)

[Scope of Claims] (a) at least one oily substance that is liquid at room temperature; (b) at least one nonionic surfactant having an HLB value in the range of 7.0 to 16.0; c) contains at least one kind of vitamin E or a vitamin E derivative and (d) water, and the weight ratio of (a):(b):(c) is 1:(0.5 to 5.0): (0.01 to 0.5) A fine emulsion characterized in that the average particle size is 10 to 200 nm, obtained by colliding preliminary emulsions with each other or colliding the preliminary emulsions with a wall. Composition.