JP2003226614A - Emulsifier having skin cell growth promoting property and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an emulsifier for cosmetics, which improves an emulsifying force and a using feeling and has a skin cell growth-promoting property. <P>SOLUTION: This emulsifier for the cosmetics comprises the aqueous solution of silk proteins consisting mainly of amorphous silk fibroin. The emulsifier for the cosmetics, wherein the aqueous solution of silk proteins is obtained by dissolving the un-degummed product, half-degummed product or degummed product of fibers (cocoon filaments) spun from silkworms in a neutral salt solution, and then dialyzing the solution. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a protein-based emulsifier and a method for producing an emulsified cosmetic using the emulsifier.

[0002]

2. Description of the Related Art Conventionally, when an emulsified cosmetic is prepared by emulsifying water and an oily substance, anionic, cationic, amphoteric, nonionic and other surfactants are generally used as emulsifiers. Has been. However, since it was pointed out that synthetic surfactants destroy the surface tissue of the skin and enter the body to cause liver damage, the direction of research and development has been toward safer emulsifiers using naturally-derived materials. We are moving in the direction we are aiming. In particular, naturally-occurring protein-based emulsifiers
Many proposals have been made because they are highly safe and generally have good affinity with the surface tissue of the skin.

In general, protein-based emulsifiers are inferior in emulsifying power to synthetic surfactants, and therefore their research is focused on increasing their emulsifying power by chemical modification (chemical modification treatment). For example, the following development examples are given. An emulsifier consisting of an amino acid alkyl esterified protein having an alkyl group having a carbon chain length of 14 to 24 (JP-A-60
-112800). A protein-based emulsifier in which an amino group of an amino acid ester is amide-bonded to the carboxyl terminal of a hydrolyzed protein (for example, JP-A-60-175531). An emulsifier consisting of a lecithin-gluten complex or a lecithin-globin complex (JP-A-63-283735). An emulsifier mainly composed of a functional protein obtained by binding an activated branched polysaccharide and a protein (Japanese Patent Laid-Open No. 1-23333).
No. 00) -Emulsifier comprising a complex of a protein or the hydrolyzate and a phospholipid (Japanese Patent Laid-Open No. 5-70332).・ Emulsifier consisting of protein complex in which lysophospholipid, free fatty acid and protein are bound (JP-A-5-56751) ・ Hydrolysis obtained by treating elastin present in animal ligament of cattle with proteolytic enzyme Of a surfactant or an aqueous solution of the hydrolyzate and a polyhydric alcohol as an emulsifier (JP-A-6-2792).
No. 54). An emulsifier containing 40% or more of the IIS globulin basic subunit in the protein of legumes (Japanese Patent Laid-Open No. 9-23837)
Issue). An emulsifier consisting of a combination of a protein and saponin or bile acid (JP-A 11-215956).

The raw material proteins used in these development examples are vegetable proteins such as soybean protein and wheat protein, collagen, gelatin, elastin, ovalbumin, serum albumin, egg yolk lecithin, milk casein, myosin, fibrinogen. Animal proteins such as are the main ones.

By the way, recently, since silk protein is a substance excellent in biocompatibility, its use in cosmetics has attracted attention, and cosmetic materials comprising various silk proteins have been proposed. For example, a water-soluble silk peptide (derived from silk fibroin) having an amino acid unit of 2 to 50 (average molecular weight of 200 to 5000) is blended with an amidocarboxylic acid type surfactant to improve a feeling of use and the like (Japanese Patent Laid-Open Publication No. HEI-8).
-20792), a liquid cosmetic containing a hydrolyzate of fibroin as a moisturizing agent (JP-A-6-157234).
JP), a water-soluble silk fibroin hydrolyzate was added to improve bath feeling (Japanese Patent Application Laid-Open No. 5-78232).
Gazette), a shampoo in which a water-soluble silk fibroin hydrolyzate having a molecular weight of about 1000 is mixed with egg yolk oil as a conditioning agent (JP-A-5-25024), carbon dioxide is added to an aqueous solution of fibroin, and then a fibroin aqueous solution is added. A gelled creamy moisturizer obtained by dispersing a microstructure obtained by adding an acid to near the isoelectric point in a dispersion medium (JP-A-10-
251299) (in this case, the pH of the aqueous fibroin solution)
The purpose is to bring about a gel with acid near the isoelectric point, and does not utilize an aqueous fibroin solution as an emulsifier. ) And other development examples. However, none of these uses silk protein as an emulsifier for cosmetics.

Very recently, an invention has been proposed in which silk protein is used as a surfactant (JP-A-11-2.
76876, Japanese Patent Laid-Open No. 2000-73090). This invention is a surfactant containing sericin or a sericin degradation product extracted from cocoon or raw silk as an active ingredient, and can be used in a wide range of fields such as pharmaceuticals, quasi drugs, cosmetics, foods and household detergents. It is said to be possible.

By the way, generally, an emulsified cosmetic obtained by using a protein-based emulsifier has a moisturizing and moisturizing feeling, but when it is actually used by picking it up, it has a tattered feeling and spreads. Often, there are problems in use such as poor sex. As an emulsifier used in cosmetics, not only safety and emulsifying power but also the feel during use are important factors.Therefore, when designing the formulation of emulsified cosmetics, these points should be fully considered. There is a need to do.

[0008] On the other hand, the inventors of the present invention have conducted researches on silk for many years and found that silk fibroin has an action of promoting the growth of human cells and utilize it in a wound dressing material and the like. (Japanese Patent Laid-Open No. 9-19221)
No. 0, JP-A No. 11-253155). It has been clarified that the action is in the H chain and L chain of fibroin constituting silk fibroin (Japanese Patent Laid-Open No. 2001-163).
899, Japanese Patent Application No. 2001-180169). However, although silk protein has a cell growth promoting action, it has not been known that its aqueous solution or its gelled substance can be used as an emulsifier. It is considered that the main reason is that the fibroin aqueous solution and its gelation product are likely to be fibrillated under a strong shearing force such as stirring, and the fibrosis product (water-insoluble lump) is separated.

[0009]

The mainstream of conventional protein-based emulsifiers is that which can be put to practical use by improving the emulsifying power and the like by chemically treating (or chemically modifying) the starting protein. , A slightly constant result. However, when the raw material protein is modified by chemical modification, various reaction steps must be performed in order to obtain the target protein-based emulsifier, and especially unreacted reagents that affect the skin are removed from the reaction system. There is a problem in that it is very difficult to remove and obtain a pure emulsifier free from impurities. The present invention solves such problems, and further,
It is an object of the present invention to provide a cosmetic emulsifier which not only improves emulsifying power and feeling of use but also has an emulsifier itself having skin cell growth promoting properties.

[0010]

The present invention has been made from the above viewpoint, and an aqueous silk protein solution which can be obtained without special chemical modification has excellent properties as an emulsifier for cosmetics and the like. Is found.

That is, the present invention resides in (1), an emulsifier consisting of an aqueous solution of silk protein containing amorphous silk fibroin as a main component.

And (2), an emulsifier for cosmetics comprising an aqueous solution of silk protein containing non-crystalline silk fibroin as a main component.

The present invention also resides in (3), a method for producing an emulsified cosmetic composition, which comprises emulsifying an oily component with an emulsifier consisting of an aqueous solution of silk protein containing amorphous silk fibroin as a main component.

Further, (4), an emulsified cosmetic composition obtained by emulsifying an oily component with an emulsifier consisting of an aqueous solution of silk protein containing amorphous silk fibroin as a main component.

Further, (5) the present invention resides in an emulsifier consisting of an aqueous gel of silk protein whose main component is amorphous silk fibroin.

Further, (6) the present invention resides in an emulsifier for cosmetics, which comprises an aqueous gel of silk protein containing amorphous silk fibroin as a main component.

Further, (7) is a method for producing an emulsified cosmetic, which comprises emulsifying an oily component using an aqueous gel of silk protein containing amorphous silk fibroin as a main component.

Further, (8) the present invention resides in an emulsified cosmetic composition obtained by emulsifying an oily component using an aqueous gel of silk protein whose main component is amorphous silk fibroin.

Further, (9), an aqueous solution of silk protein containing amorphous silk fibroin as a main component neutralizes unrefined, semirefined and refined products of silkworm spit fibers (cocoon yarn). The above emulsifier for cosmetics is an aqueous silk protein solution obtained by dissolving with salt and then dialysis.

Further, (10), an aqueous gel of silk protein whose main component is non-crystalline silk fibroin is a non-scoured product, a semi-scoured product, a scoured product, etc. of fibers (cocoon thread) spun from silkworms. It exists in a cosmetic emulsifier which is an aqueous gel of silk protein obtained by gelling an aqueous silk protein solution obtained by dissolving with a soluble salt and then dialysis.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION An aqueous solution of a silk protein having a non-crystalline silk fibroin as a main component or an aqueous gel of a silk protein having a non-crystalline silk fibroin as a main component of the present invention is mixed with an oily component, It is possible to uniformly emulsify water and an oily component in an aqueous silk protein solution or an aqueous gel thereof. Moreover, since silk fibroin has a skin cell growth promoting action, it is possible to obtain a cosmetic emulsifier which not only improves emulsifying power and feeling of use but also emulsifier itself has skin cell growth promoting properties.

The present invention includes 1) cocoon yarn spun from silkworm and raw silk which is a processed product of cocoon yarn,
Starting materials are unrefined products such as silk thread and silk woven fabrics, semi-refined products, refined products, etc. 2) Dissolve these starting materials with neutral salt, and then dialyze with water, and 3) obtain the resulting silk protein aqueous solution. (A) use as an emulsifier as it is, or (b) once obtain an amorphous silk substance by drying an aqueous silk protein solution, and use the dried amorphous silk substance in water when using it as an emulsifier. To be used as an emulsifier by regenerating the silk protein aqueous solution, or 4) using the silk protein aqueous solution at 40 to 130 ° C., preferably 5
It includes an embodiment in which it is left to stand in an atmosphere of 0 ° C to 80 ° C to be gelled and is used as an emulsifier in the state of an aqueous gel. The thus-prepared emulsifier is added with a cosmetic oily component, and if necessary, various cosmetic additives, and the mixture is stirred to obtain a desired emulsion or cream-like cosmetic emulsion. Is something that can be done.

Examples of emulsified cosmetics or quasi drugs that can be produced using the emulsifier of the present invention include:
Cleansing cosmetics (makeup soap, face wash, shampoo, conditioner, etc.), hair cosmetics (hair dye, cosmetics for hair, etc.), basic cosmetics (general cream / milky lotion, shaving cream, lotion / cologne, shaving lotion, makeup oil,
Makeup cosmetics (foundation, etc.)
Eyebrow, eye cream, eye shadow, mascara, etc., fragrance cosmetics (perfume, etc.), sunburn, sunscreen cosmetics (sunblock, sunblock, sunblock, sunblock lotion, sunblock, sunblock oil, etc.), nail cosmetics (nail cream) Etc.), eyeliner cosmetics (eyeliner etc.), lip cosmetics (lipstick, lip balm etc.), oral cosmetics (toothpaste etc.), bath cosmetics (bath cosmetics etc.) and the like. The details of carrying out the present invention will be described below.

A. Raw material The raw material of the silk protein of the present invention, which is mainly composed of the amorphous silk fibroin, is cocoon thread, raw thread, silk woven or knitted fabric, silk thread (fibroin fiber), their residual thread or their unscoured product, semi-scoured product, scoured product. It is possible to target all of the substances and the protein fibrous substances spun by silkworms such as domestic silkworms and wild silkworms, such as fibers, powders, films, etc. using them as raw materials.

Generally, silkworms secrete silk into the silk gland cavity in the body,
This silk is called liquid silk. Liquid silk consists of fibroin and sericin (these are called silk proteins), and liquid fibroin has a molecular weight of about 370,000 (Tasiro Yutaka
and Otsuki Eiichi, Journal of Cell Biology, Vol, 4
6, Pl (1970)). Fibroin having a molecular weight of about 370,000 is divided into a molecular weight of about 350,000 (H chain) and about 25,000 (L chain).

Silkworms spit liquid silk during cocooning to make cocoons (composed of cocoon threads and pupae). It is known that fibroin is present in the center of cocoon thread and sericin is present in the periphery, and the abundance ratio is (70-80% fibroin): 20-30% (sericin). Raw silk is made by collecting several to several tens of cocoon threads. A fabric woven with raw silk is called raw woven. The step of removing sericin from cocoon thread, raw silk or raw woven fabric is called scouring, and the fiber after scouring is silk thread or fibroin fiber.

As for silk yarn, first, a cocoon produced by a sericulture farmer is dried and boiled and then silk reeled to produce raw silk, and then raw silk or raw woven is refined to obtain silk silk or silk fabric. The waste generated in these processes is the residual yarn. Dry cocoon is cocoon 115-12
The temperature is gradually lowered from 0 ° C to about 80 ° C over 5 to 6 hours. Boiled cocoons are treated with steam and hot water at 100 to 105 ° C for 10 minutes.

B. The most common scouring method is boiling in an aqueous solution containing an alkaline sodium salt or soap (alkali soap scouring). In addition, when scouring with only alkaline sodium salt (alkali scouring), immersing in pressurized hot water (for example, 120 ° C. hot water) for scouring (high pressure scouring), and scouring with enzymes (enzyme scouring), etc. is there.
Although it may be boiled and scoured with water only, sericin remains uncommon due to the large amount of residual sericin. Silk yarn is obtained by such scouring. Here, it is called un-scouring when not being scoured, and semi-scouring when the scouring is not complete.

The product obtained by semi-scouring is also called silk thread, but it is not called fibroin fiber. Here, when fibroin is 99% or more, it is referred to as fibroin fiber. Examples of the alkaline aqueous solution used when scouring the raw materials include aqueous solutions of alkaline sodium salts such as sodium carbonate, sodium hydrogen carbonate, sodium silicate, sodium metasilicate, sodium phosphate, and sodium hydroxide. In the case of alkaline scouring, an aqueous solution of sodium carbonate is particularly preferable because it has an appropriate buffer effect. The raw material is de-sericinized by scouring.

In order to obtain the silk protein as the emulsifier of the present invention, not only the silk thread may be obtained by scouring, but the raw material may not be scoured, and an unscoured product obtained by finishing the scouring may be used. In addition, a silkworm silkworm silkworm cocoon thread (made of sericin), which is a mutant of domestic silkworm, may be added when an aqueous solution mainly containing amorphous fibroin is prepared. Sericin is a protein whose structural unit is mainly composed of serine (3-hydroxyalanine) and is mainly composed of a segment having a hydrophilic methylol group in its side chain, and fibroin containing many non-hydrophilic groups in its side chain. It is considered that the function as a moisturizer is stronger than that of.

That is, fibroin is -Gly-S.
er-Gly-Ala-Gly-Ala- is a repeating unit, and the constitution of the non-hydrophilic group per unit of -Ser- having a hydrophilic group is -Gly-Ala-Gly.
Since it consists of 5 units of -Ala-Gly-, the hydrophilic-lipophilic balance (HLB value) is in an intermediate range, and a wide range from 0 / W type emulsion to W / O type emulsion. On the other hand, it is considered that sericin, which is mainly formed from a structural unit having a hydrophilic group, is superior in the moisturizing function to the emulsifying power as compared with fibroin.

Incidentally, sericin has been reported to always have a hygroscopic property of 15% higher than that of fibroin (Koji Kataoka, Journal of Japan Silkworm Society, "Water content of liquid silk and cocoon yarn in spit yarn of domestic silkworm" 50) Volume, Issue 6, P478-483
(1981)). When a small amount of sericin is contained, it may be effective as a skin care material because it suppresses fibrosis due to so-called shear and enhances moisturizing properties.

C. Preparation of Silk Protein Aqueous Solution In a processing step such as scouring, silk is subjected to high-temperature and high-humidity treatment containing alkali, so that silk protein is easily decomposed and its molecular weight is lowered. Silk proteins are easily decomposed by acid, alkali, high temperature (especially wet heat) and light (especially ultraviolet rays and radiation) to lower the molecular weight. Even in the case of dissolution with a neutral salt, the molecular weight tends to decrease. Since the decrease in the molecular weight of silk protein is related to the decrease in the cell growth promoting property of silk protein, an extreme decrease in molecular weight is not preferable. In order to obtain the silk protein as the emulsifier of the present invention, the above raw materials are dissolved and obtained as follows.

Aqueous silk protein aqueous solution containing non-crystalline silk fibroin as a main component; in the present invention, a silk protein containing silk fibroin as a main component when the sericin content of the silk protein is less than about 50%. Examples of neutral salts that are silk solubilizers include neutral salts such as calcium chloride, copper ethylenediamine, sodium thiocyanate, lithium thiocyanate, lithium bromide and magnesium nitrate. Saturated aqueous solution or 50% of the neutral salt
[Weight (g) / Volume (mL)] A concentration of saturation or higher is preferable.

In the step of dissolving silk in a neutral salt solution, alcohol such as methyl alcohol, ethyl alcohol and propyl alcohol is added to the neutral salt and the temperature is kept at 94 ° C. or lower, preferably about 75 to 85 ° C. Should be done in.
In this case, the dissolution can be promoted by stirring. If the melting temperature is low, it will not dissolve easily. If the melting temperature is high, it will be easily dissolved, but the molecular weight will be significantly reduced. A solution obtained by dissolving silk with a neutral salt contains fibroin or a mixture of fibroin and sericin, a neutral salt, alcohol and the like. Insoluble matter is first removed from this solution, and then low molecular weight substances having a molecular weight of about 5,000 or less are removed using a dialysis membrane or a dialysis machine. An aqueous silk protein solution is obtained by such dialysis. Approximately 0.001 to 0.1 M of calcium chloride may remain in this silk protein aqueous solution.

On the other hand, the higher the molecular weight of the silk protein in the aqueous solution, the easier it is to fibrillize due to vibrations or shear during stirring. Since the fibrous substance becomes a water-insoluble lump, it becomes a cause of lowering the feeling of use (touch) as a cosmetic.
For this reason, it is preferable that the molecular weight of the silk protein is reduced to some extent, but a high-molecular-weight silk protein may be contained since it is difficult to cause fibrosis by making the emulsification method and the usage method gentle. Fibroin
It acts as an emulsifier with an average molecular weight (weight average) of 5,000 or more. However, at 5,000 to 20,000, there is almost no cell growth effect. If it is 20,000 to 40,000, the cell growth action is small, but it can be used as the emulsifier of the present invention. The average molecular weight of fibroin having sufficient cell growth promoting property is 40,000 to 370,000. Therefore, as the material for skin care, one having an average molecular weight in the range of 60,000 to 300,000 is particularly preferable.

D. Amorphous powder or film is prepared from an aqueous solution of silk protein containing non-crystalline silk fibroin as a main component, and this is dissolved again in water to obtain an aqueous silk protein solution again; the aqueous solution of C. is smoothed on a solid surface. It is also possible to obtain an aqueous silk solution by again immersing the non-crystalline silk film produced by casting and drying in water. The non-crystalline silk protein may be a powder or a powder. In this case, the silk protein aqueous solution can also be obtained by spray drying, freeze drying, or the like.

In the present invention, the non-crystalline silk fibroin has a crystallinity of less than 10% (Japanese Unexamined Patent Publication No. Hei 11 (1999)).
-70160). Even if it contains silk sericin,
A crystallinity of less than 10%. When the degree of crystallinity is less than 10%, when this silk protein is immersed in water, a part of the silk protein dissolves, and even if it partially absorbs water and floats, it is a very soft and aqueous gel. And acts as an emulsifier. In this case, as compared with the case where the silk protein aqueous solution is used as an emulsifier as it is, the drying and redissolving steps are further performed, which is disadvantageous in that the number of steps is large.

However, the amorphous silk can be stored for a long period of several years in a room with a relative humidity of about 50% or less in which light is blocked, and since it is dry, it is light and suitable for long-distance transportation. There are advantages such as being effective. The silk protein aqueous solution can also be obtained from liquid silk. For example, a silk protein aqueous solution can be obtained by taking out a gel-like content (liquid silk) from the middle and posterior glands of the silk gland of silkworm and dissolving it in water.

However, in this method, it is necessary to dissect the silkworm, take out the silk gland from the silkworm body, and take out liquid silk from the silk gland cavity. The maximum amount of silk obtained from one silkworm is about 0.4 g, and it is easy to contain impurities such as silkworm body fluid and silk gland cells, and it takes time to obtain silk. I won't. In the present invention, cocoon layers or cocoon threads of raw cocoons, dried cocoons or boiled cocoons, which are industrially advantageous, or raw silk, silk fabrics or residual threads thereof are used as materials.

E. The emulsified oily component of the silk protein aqueous solution includes vegetable oils such as olive oil, camellia oil, avocado oil, cacao oil, sunflower oil, persic oil, palm oil, castor oil and other animal oils, as well as jojoba oil and beeswax. Oils such as waxes, etc. listed in the cosmetic raw material standard, and oily components such as waxes are used. There is no great difference in the properties of the emulsion depending on the type of oily component.

A desired cosmetic is prepared by appropriately adjusting the concentration of the silk protein aqueous solution and the ratio of the oily component to the silk protein aqueous solution amount. As a method of mixing the silk protein aqueous solution and the oily component and emulsifying the mixture, there are a stirring method, a grinding method and the like, but either method may be used. It is desirable to properly use the emulsifying machine depending on the concentration of silk and the ratio of oil. The viscosity of the emulsion changes depending on the concentration of the silk aqueous solution, and when the concentration of the silk aqueous solution is low, the cell growth by silk protein is low. Therefore, the concentration is 0.1% or more, preferably 0.5% or more.

On the other hand, when the concentration of the silk protein aqueous solution is high, the elongation on the skin is lowered and the feeling of use is lowered. Therefore, the concentration is 15% or less, preferably 10% or less. When the ratio of sericin exceeds 50%, the property of sericin becomes strong and gelation easily occurs, which is not preferable. It is more preferably 30% or less. The emulsion becomes liquid when the concentration of the silk protein aqueous solution is low (about 3% or less), and can be used as an emulsion. As the concentration increases (about 3% or more), it becomes viscous and can be used as a cream or ointment. The fact that the cell growth rate is low when the silk fibroin concentration is low and the elongation is reduced when the silk protein aqueous solution concentration is high is the same as in the case of emulsification of the aqueous gel described below.

F. Gelation of silk protein aqueous solution Gelation is achieved by leaving the silk protein aqueous solution as it is. The higher the concentration of silk protein aqueous solution, the faster the gelation. When the concentration is 3%, it takes about one week for gelation at room temperature (25 ° C. ± 5 ° C.), and when the temperature is lowered to room temperature or lower, the gelation time becomes drastically longer. When the silk fibroin aqueous solution is kept at room temperature or higher, particularly 40 ° C. or higher, gelation occurs within about 2 days. In addition, the autoclave (120
(° C), gelation occurs in about 1 to 2 hours. Fifty
It is preferable to stand at a temperature of -80 ° C to cause gelation.

When the concentration of fibroin exceeds a certain level, the aqueous silk protein gel has -C = O- in the fibroin chain.
And -NH- form hydrogen bonds with other neighboring fibroin molecules and are loosely entangled with each other to form a three-dimensional network. Since this aqueous gel is in a very brittle state, the gel state is easily broken by an external force.

Therefore, the silk gel aqueous solution containing fibroin as a main component and having a water content of 4.5% was stirred without oily components, and the agitated product was separated by a centrifuge (8,000).
After 0 rpm for 10 minutes), the silk protein concentration of the supernatant was 0.1 to 2.0%. To the precipitate excluding the supernatant liquid, water corresponding to the supernatant liquid was added and stirred again (30
Second) and centrifugation (8,000 rpm, 10 minutes), the concentration of the silk protein aqueous solution in the supernatant was similarly 0.
It was 1 to 2.0%. A part of such a gel has a property of being easily dissolved in water by stirring, and this is called an aqueous gel. The silk protein aqueous solution thus obtained or its aqueous gel acts as an emulsifier when mixed with an oily component. An aqueous gel of silk protein that can be used as an emulsifier can be obtained by a method other than the present invention, such as an isoelectric point method.

G. The emulsification method of silk protein aqueous gel is described in the above-mentioned E. The same as in the case of the silk protein aqueous solution. When the concentration of silk protein in the gel is about 6% or more, it is difficult to emulsify the gel by mixing the oily component and stirring the mixture. As the concentration increases, emulsification becomes easier when water is added during stirring. Water needs to be equivalent to twice as much as silk protein. That is, 10 to 20 g of water may be added to 100 g of the gel having a concentration of 10% and stirred. Compared with the case of emulsification with silk protein aqueous solution,
It is industrially disadvantageous to gelate an aqueous silk protein solution and then to emulsify it, since it involves many gelling steps.

However, emulsification with an aqueous gel of silk protein has the advantage that it can be emulsified even when the ratio of oily component is smaller than that of the silk protein aqueous solution. That is, when the water content is the same, the use of an aqueous gel rather than the aqueous solution of silk protein can change the ratio of the oily component and the silk fibroin in a wide range, so that an emulsion having different properties can be obtained. It is presumed that the reason for this is that since silk fibroin is loosely bound between the molecules due to gelation of the silk protein aqueous solution, not all silk fibroin chains need to bind to the oil component.

The emulsified cosmetic composition of the present invention has the functions and effects of the present invention.
If necessary, a pH adjuster within a range that does not impair the effect,
Commonly used in cosmetics such as preservatives, thickeners, moisturizers, bactericides, anti-inflammatory agents, pigments, fragrances, antioxidants, UV absorbers, vitamins, organic or inorganic powders, alcohols and sugars. It goes without saying that the components can be appropriately mixed.

[0050]

[Example 1] -Emulsification of oily substance by silk protein aqueous solution The cocoon layer of domestic silkworm cocoons produced in the spring of 2001 was dried by a conventional method.
Boiled cocoons and reeled raw silk are used as raw materials, and 300 g of this raw silk is used as 1
It was scoured by boiling in 2 liters of water and 6 g of sodium carbonate for 40 minutes. The reduction is 25.7% and the fibroin is 99
It is considered that more than 100% of silk thread was obtained. This silk thread (150
g) is calcium chloride, ethanol, water molar ratio 1: 2
It was dissolved with a liquid of a ratio of 8 (10 times the amount of silk thread). The dissolution was carried out at 75 to 80 ° C. for 60 minutes, and dialyzed.

For dialysis, the solution is dialyzed with a dialysis membrane [Sanko Junyaku Co.
UC36-32-100] and immersed in pure water for dialysis. In the electrophoretic image of fibroin after dialysis, the H chain of fibroin was slightly confirmed, but the L chain was confirmed, and the weight average molecular weight by chromatography was about 240,000. The concentration of the silk protein aqueous solution after dialysis is 8.2%
Met. This concentration was diluted with pure water to prepare 4.0%, 2.0%, 1.0% and 0.2% silk protein aqueous solutions in addition to 8.2%. Further, while the silk aqueous solution having a concentration of 8.2% was put in the dialysis membrane, it was dried in a room at 5 ° C.
A 2% aqueous silk solution was obtained. Olive oil was added to these silk protein aqueous solutions having different concentrations and stirred (coffee mixer, about 20 seconds) to emulsify.

After stirring, the emulsion was placed on the arm in an amount of 0.1 to 0.3 g, and was spread over a width of about 100 cm ² using fingers to apply the emulsion. When it was applied to the skin, the range of use as a cosmetic was examined based on the ease of spreading the emulsion (spreadability) and the ease with which small lumps came out of the emulsion (tattered feeling). The result is shown in FIG. The horizontal axis of FIG. 1 represents the protein concentration (%) of the silk protein aqueous solution. The vertical axis represents the oil fraction = 100 x oil fraction (g) / {silk protein aqueous solution (g) +
Oiliness component (g)} is shown. The range that can be used as an emulsion or cream is the part surrounded by the solid line A, preferably the part surrounded by B.

[0053]

Example 2 Emulsion of Silk Protein Aqueous Solution from Dry Amorphous Silk Protein (Film or Powder) The silk protein aqueous solution having a concentration of 4.0% prepared in Example 1 was placed in a room at 25 ° C. and 40% RH. On a plastic plate,
A silk film was prepared by drying while blowing air. The obtained non-crystalline silk film was immersed in water at 20 ° C. and dissolved to prepare silk protein aqueous solutions having concentrations of 6.0%, 4.0%, 2.0% and 1.0%. Olive oil was added to these and stirred as in Example 1 to emulsify them. The relationship between the concentration of the silk protein aqueous solution which can be used as a cosmetic for the obtained emulsion and the oily fraction was the same as that shown in FIG.

[0054]

[Example 3] Emulsification of oily silk protein aqueous gel 300 g of a cocoon layer of silkworm was dipped in a boiling solution of 6 g of sodium carbonate and 12 l of water, and scoured for 100 minutes. This silk thread 195
g was dissolved in a solution of 392 g of calcium chloride, 508 g of water and 325 g of ethanol. The melting temperature is 75 to 85 ° C,
The time is 3 hours.

For dialysis, tap water was changed for the first 2 days and then pure water was changed 8 times for 2 days. The H chain of fibroin cannot be confirmed from the electrophoresis image of the silk aqueous solution. The L chain was not clearly confirmed, and the average molecular weight was about 65,000 by gel chromatography. The concentration of this silk aqueous solution is 14.1%
Met. In addition, the concentration of 6.0%, 3.0%, 1.0%,
0.2% was prepared, and these were left to gel at 70 ° C. Olive oil was added to the obtained silk protein aqueous gel and stirred (coffee mixer, stirring for about 30 seconds) to emulsify.

The emulsion thus obtained was placed on the arm in an amount of 0.1 to 0.3 g, and spread out to an area of about 100 cm 2 using a finger (speed of about 20 to 200 cm / sec, 20 to 200 g).
Applied to the skin. At this time, the easiness of elongation of the emulsion and the easiness of forming small lumps from the emulsion (tattered feeling) were examined to determine the range of use as a cosmetic. The result is shown in FIG. The horizontal axis of FIG. 2 is the protein concentration (%) of the silk protein aqueous solution. The vertical axis shows the oil fraction =
100 x oil content (g) / {(silk protein aqueous solution (g) +
Oil content (g) + W (g)} is shown. W is the weight of water added at the time of stirring when the concentration of the gelled product is high. The area that can be used as emulsion or cream is the area surrounded by the solid line A,
It is preferably a portion surrounded by B.

[0057]

[Example 4] Preparation of silk protein aqueous gel: 300 g of a silkworm cocoon layer was immersed in a boiling solution (about 100 ° C) of 6 g of sodium carbonate and 12 l of water, and scouring was carried out for 70 minutes. 150 g of this silk thread was dissolved in a solution of 392 g of calcium chloride, 508 g of water and 325 g of ethanol. Melting temperature is 75-8
The temperature is 5 ° C. and the time is 2 hours. The dialysis was replaced with tap water for the first 2 days and then with pure water 8 times for 2 days.

From the electrophoretic image of the silk protein aqueous solution, the H chain of fibroin could not be confirmed, but the L chain was slightly confirmed. Average molecular weight by gel chromatography is about 1
It was 30,000. The obtained 9.41% concentration silk protein aqueous solution was diluted with water to prepare 3.12% and 0.20% silk protein aqueous solutions. These silk protein aqueous solutions were placed in a beaker and placed in a thermostatic chamber to examine gelation time.
An autoclave was used for 120 ° C.

The gelation was confirmed because the silk protein aqueous solution became milky white, but was based on the case where the silk protein aqueous solution did not spill from the beaker when the beaker was tilted.
However, if the concentration of the silk protein aqueous solution is about 3% or less,
The gel condition is very brittle and spills just by tilting it. In this case, pay attention to the bubbles contained in the gel, and make sure that the bubbles do not move even if the gel is tilted 10 to 30 ° with respect to the horizontal. The gel point was used. The result is shown in FIG. The silk protein aqueous solution gels in about 2 to 4 days at a temperature of 50 to 80 ° C. The gelation time changes to a shorter time by receiving a shearing force such as heat or stirring. A hydrophobic substance (for example, polyethylene glycol, glycerin, etc.) may be added to facilitate gelation.

[0060]

[Comparative example] -Emulsified silkworm silkworm cocoon layer (5.0 g) separated by an aqueous sericin solution was separated into several sheets, and this was immersed in 40 times (200 g) 8M urea water at 80 ° C for 15 minutes,
Stir well. The reduction by this scouring was 21.2%. The refined solution was dialyzed against 50 times amount of pure water (4 times every 2 hours). The concentration of this solution is 0.25% after dialysis.
And it was already gelling. The gelled sericin becomes an aqueous sericin solution when the temperature is raised. This liquid was boiled and the boiling time was changed. The sericin concentration thus obtained was 1.
An 85%, 3.24%, 5.48% aqueous solution was prepared. A precipitate floats in the aqueous solution having a concentration of 3.24% and 5.48% even during boiling. Olive oil was added to these aqueous sericin solutions and stirred. The emulsion that was emulsified by stirring was extended to the hand and judged as a cosmetic from the feel and the ease of extension.

As a result, when the concentration was less than 6%, an emulsion could be obtained, but compared with the case of using an aqueous silk protein solution containing fibroin as a main component,
When the temperature during use is high, it becomes soft, and when the temperature is low, it becomes hard easily. When an aqueous solution of sericin is used as an emulsifier, the concentration thereof can be used in the range of 0.1% to 6%, preferably several 0.1% to 4%, more preferably 0.1%.
To 2%. The concentration can be increased as the proportion of fibroin mixed in the aqueous sericin solution increases.

[0062]

[Test Example] (Test Example 1) Skin Irritation A patch test relating to skin irritation was carried out on the cosmetic creams of the other two companies (one each) that did not use the emulsion cream of the present invention and the silk protein aqueous solution. As the emulsified cream of the present invention, an aqueous gel of silk protein having a silk protein concentration of 4.5% (silk gel) obtained by the method of Example 4 was used,
The cosmetic materials and the amount ratios shown in Table 1 were mixed and stirred to obtain a silk cream.

Regarding these three points, 10 girls (1 in their teens, 4 in their 20s, 3 in their 30s, 40 in their 20s)
A patch test was carried out for two people. In the patch test, Finn-Chamber was used to apply silk cream, creams of Company A and Company B on the inside of the arm, and after 48 hours and 7
Two hours later, the skin reaction was evaluated according to the criteria (Shojiro Nakagawa: Clinic for contact dermatitis, clinical immunity). 4 after pasting
After 8 hours and 72 hours, by visual observation of the applied part,
The degree of irritation was determined as shown in Table 2, and the scores were scored. The total score of each sample was divided by the number of subjects to calculate 100 times, and the stimulation index is shown in Table 3. From Table 3, the skin cream was not irritating to the skin, but the creams of other companies containing no silk protein were irritating to the skin.

(Test Example 2) 5.0 g of cocoon layer of silkworm silkworm mainly composed of non-crystalline silk fibroin, which promotes cell growth, was immersed in 200 ml of 8M 8M urea water at 80 ° C., and stirred for scouring. . The scouring time is (1) 20 minutes and (2) 10 minutes, and the respective scouring time is (1) 25.8.
% And (2) 21.2%. Further, 5.0 g of the cocoon layer was boiled and scoured with 200 ml of water for (3) 30 minutes and (4) 15 minutes. Each reduction is (3) 16.0%, (4) 8.
It was 7%. The unrefined cocoon layer was designated as (5).
In (1), most sericin is excluded, and 99% or more is considered to be fibroin. In order to obtain the value of the sericin content in the silk proteins of (1) to (5), these are treated with water 1
9 in a boiling liquid containing 0.05 g of sodium carbonate in 00 ml
It was dipped for 0 minutes, thoroughly stirred, and scoured. The weight loss after scouring was calculated as the amount of sericin. In addition, a sericin silkworm cocoon layer [100% sericin (8)] was added to the domestic silkworm cocoon layer to give a sericin ratio of 50.0% (6), 75.0% (7).
made.

The coating of silk on the cell culture vessel was performed as follows. 0.01 of each of these (1) to (8) silk proteins
g was dissolved in 1.0 ml of 9M LiSCN, and each solution was added to 5 ml.
Dialyze 5 times with 0 times amount of water, and each silk protein after dialysis 0.0
1 ml of 025% solution was added to a petri dish (35 mm) for cell culture.
(φ, Falcon), air dried, washed 3 times with 2 ml of PBS, air dried again, and sterilized with 70% ethanol.

Human dermal fibroblasts purchased from Kurabo Industries, Ltd. were used as the cells. The medium used was a low serum medium for dermal fibroblast proliferation purchased from Kurabo. The culture was carried out by adding 2 ml of the medium to each petri dish coated with silk protein and inoculating ˜70,000 cells for 3 days. The number of cells is measured by alama blue (IWAKI) per dish.
Add 0.1 ml, and after 2 hours at 37 ° C, 570 nm, 6
The reduction amount of the dye calculated from the absorbance at 00 nm was defined as the number of growing cells. Table 4 shows the cell growth number of the petri dish coated with silk protein, using the petri dish not coated with silk protein as a control (100%). When silk protein was coated, the cell growth was superior to the control group regardless of the difference in sericin content.

(Test Example 3) Molecular Weight of Fibroin and Cell Growth-Promoting Water Sodium carbonate 0.5 g was put in 1,000 cc of water, boiled (100 ° C.), and 10.0 g of cocoon layer of domestic silkworm was immersed in the boiled water. , Stirred and refined. Scouring time is (1) 5 minutes, (2)
20 minutes, (3) 60 minutes, (4) 130 minutes, (5) 180
Minutes Each reduction is (1) 22.3%, (2)
24.5%, (3) 25.1%, (4) 25.5%,
(5) It was 26.2%. It is considered that 99% or more of (4) and (5) is fibroin. The relationship between the molecular weight (weight average) and cell viability of these silk proteins was examined. A gel chromatography column was used to measure the average molecular weight, and the sample was analyzed using 8M urea / 40mM Tris-H2SO4 (pH
Elution at 8) (0.6 ml / min) and monitoring at 275 nm. Column for molecular weight measurement is Superdex 200 Pre
p grade (Pharmacia) was used.

Next, the cell viability of (1) to (5) was measured as follows. First, the coating of silk on the cell culture vessel was performed as follows. 0.01 g of each silk protein of (1) to (5) was dissolved in 1 ml of 9M LiSCN, and each solution was dialyzed 4 times with 50 times amount of water to obtain a silk protein aqueous solution. 1 ml of a 0.0025% solution of each silk protein was placed in a petri dish (35 mmφ, Falcon) for cell culture, air-dried, washed 3 times with 2 ml of PBS, air-dried again, and immersed in 70% ethanol for sterilization.

Human dermal fibroblasts purchased from Kurabo Industries Co., Ltd. were used as the cells, and a low serum medium for skin fibroblast growth purchased from Kurabo Industries was used as the medium. The culture was carried out by adding 2 ml of the medium to each petri dish coated with silk protein and inoculating ˜70,000 cells for 3 days. The number of cells was measured by adding 2 ml of medium and 0.1 ml of Alama Blue (IWAKI) to each petri dish, and after 2 hours at 37 ° C., 57 ml was added.
The amount of dye reduction calculated from the absorbance at 0 nm and 600 nm was defined as the number of viable cells. FIG. 4 shows the number of cells grown in a petri dish coated with silk protein, using a petri dish not coated with silk protein as a control (100%). Cell viability decreased as the molecular weight of fibroin decreased, but it has cell growth promoting activity when the molecular weight of fibroin is about 40,000 or more.

Although the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications can be made as long as the operation and effect described in the specification can be obtained.
For example, it is needless to say that it can be used for food (chocolate emulsifier etc.), medical use (ointment etc.), cleaning (detergent etc.) and other fields.

[0071]

The emulsifier for cosmetics of the present invention, which is composed of an aqueous solution of silk protein or an aqueous gel containing non-crystalline silk fibroin as a main component, not only improves the emulsifying power and the feeling of use, but also the emulsifier itself. Has skin cell growth promoting properties.
Therefore, an emulsion obtained by emulsifying an oily component using this emulsifier can be used in emulsified cosmetics having a wide range of oil-water compositions and is extremely excellent in skin care.

[0072]

[Table 1]

[0073]

[Table 2]

[0074]

[Table 3]

[0075]

[Table 4]

[Brief description of drawings]

FIG. 1 is a graph showing the relationship between the oil content of silk cream and the concentration of silk aqueous solution.

FIG. 2 is a diagram showing the relationship between the oil content of silk cream and the concentration of silk gel.

FIG. 3 is a diagram showing the relationship between the concentration (%), the temperature (° C.), and the time (day) related to gelation of a silk aqueous solution.

FIG. 4 is a diagram showing silk protein (weight) average molecular weight and cell growth rate (%).

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kozo Tsubouchi             3-3-1 Kinunodai, Taniwahara Village, Tsukuba-gun, Ibaraki Prefecture             -9-302 (72) Inventor Shoko Fujiura             6-11-13-608 Fukushima, Fukushima-ku, Osaka City, Osaka Prefecture               Inside Audremann Co., Ltd. F term (reference) 4C083 AA122 AC122 AC482 AD451                       AD452 AD532 AD662 CC02                       DD31 EE01 EE05 EE10 EE12                       FF01 FF05

Claims (10)

[Claims] 1. An emulsifier consisting of an aqueous solution of silk protein whose main component is amorphous silk fibroin. 2. A cosmetic emulsifier comprising an aqueous solution of silk protein containing amorphous silk fibroin as a main component. 3. A method for producing an emulsified cosmetic, which comprises emulsifying an oily component using an emulsifier consisting of an aqueous solution of silk protein containing amorphous silk fibroin as a main component. 4. An emulsified cosmetic product obtained by emulsifying an oily component with an emulsifier consisting of an aqueous solution of silk protein whose main component is amorphous silk fibroin. 5. An emulsifier consisting of an aqueous gel of silk protein whose main component is amorphous silk fibroin. 6. An emulsifier for cosmetics, which comprises an aqueous gel of silk protein whose main component is amorphous silk fibroin. 7. A method for producing an emulsified cosmetic, which comprises emulsifying an oily component using an aqueous gel of silk protein whose main component is amorphous silk fibroin. 8. An emulsified cosmetic product obtained by emulsifying an oily component using an aqueous gel of silk protein containing amorphous silk fibroin as a main component. 9. An aqueous solution of silk protein containing amorphous silk fibroin as a main component dissolves unrefined, semirefined and refined products of silk-fiber spun silk (cocoon yarn) with a neutral salt, The emulsifier for cosmetics according to claim 2, which is an aqueous solution of silk protein obtained by subsequent dialysis. 10. An aqueous gel of silk protein containing amorphous silk fibroin as a main component is prepared by dissolving an unscoured product, a semi-scoured product, a scoured product, etc. of a silkworm spun fiber (cocoon thread) with a neutral salt. The cosmetic emulsifier according to claim 6, which is an aqueous silk protein gel obtained by gelling an aqueous silk protein solution obtained by dialysis.