JP2016160211A - Soluble kerateine, manufacturing method of the same, and application of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide soluble reduction type keratin (kerateine) which does not require means such as modification and is not needed to be reduced prior to use while having physical properties such as excellent solubility, a manufacturing method thereof, and composition containing the keratin.SOLUTION: There are provided soluble kerateine obtained by processes (1) to (4) below and a composition containing the kerateine. (1) after α- keratin is reduced at pH9 to 13.5 while adding thioglycolic acid or salt thereof under the presence of water, insoluble residue is removed by filtration to obtain filtrate; (2) the obtained filtrate is adjusted to pH2.5 to 7, and generated sediments are recovered and rinsed; (3) the recovered sediments are dissolved in alkali solution of pH9 to 12, and thioglycolic acid or salt thereof is added under an inert condition; and (4) reaction liquid is adjusted to pH4 to 7, generated sediments are taken by filtration and rinsed to obtain solubilized kerateine.SELECTED DRAWING: Figure 3

Description

  The present invention relates to soluble keratein (reduced keratin) and uses thereof, and more specifically, prior to use while having excellent physical properties such as solubility without modifying the sulfhydryl group (-SH group) at the keratin end. The present invention relates to soluble keratein that does not need to be reduced and its use.

  Keratin fibers (α-keratin) typified by animal hair fibers such as wool have a composite structure in which crystalline microfibrils composed of α-helix molecules are embedded in an amorphous matrix. This α-keratin has a large network structure with a high cross-linking density, having a large amount of disulfide bonds (SS bonds) between and / or within the protein (keratin chain molecule) having such a complex structure. It is a natural polymer formed that is insoluble in water.

  Conventionally, attention has been paid to the hygroscopicity of α-keratin and the toughness that does not break even when bent, and attempts have been made to apply it to various new uses. As one of the methods, an attempt has been made to solubilize α-keratin and use it as a new chemical material.

  For example, in Patent Document 1, wool is used as α-keratin, and this is reduced with thioglycolic acid in the presence of a large amount of urea (protein denaturant), and then further thioglycolic acid is added in the presence of an oxidizing agent. A method of obtaining soluble keratin by reacting has been proposed. This technique promotes solubilization of α-keratin by cleaving hydrogen bonds in α-keratin with urea.

  However, this method has a problem that the yield of soluble keratin (the solubilization rate of α-keratin) is low even in the presence of a large amount of a protein denaturant and is about 31.7 to 51.4%. In addition, in order to use the soluble α-keratin obtained by this method, it is necessary to remove the protein denaturant from the soluble keratin solution, and there is a problem that the process becomes complicated such as a dialysis step must be included. there were.

  The present inventors previously developed and reported a new method for obtaining a soluble keratin derivative (carboxymethylalanyl disulfide keratin; CMADK) without using a protein denaturant (Patent Document 2). In this method, α-keratin is first brought into contact with sodium thioglycolate in the presence of water, and then an oxidizing agent is added to the obtained treatment liquid to produce soluble CMADK.

  By such a method, it becomes possible to solubilize keratin, and the polymer regenerated from the obtained soluble CMADK is a protein having various properties as a protein having the same properties as the original α-keratin. It is also disclosed in Patent Document 2 that it can be used as a raw material for a regenerated protein product such as regenerated fiber.

  The above-mentioned CMADK is soluble in water and can be used in various ways. However, it has a problem that it is difficult to use because it requires a reduction treatment.

JP-A-7-126296 JP 2009-23924 A

  As mentioned above, the production of soluble keratin is already possible, but this has the problem that it must be reduced before use, which is a bottleneck for practical use. The present invention has been made in view of such circumstances, and soluble reduced keratin (keratein) which does not require a means such as modification and does not need to be reduced prior to use while having excellent physical properties such as solubility. It is an object of the present invention to provide a manufacturing method thereof.

  As a result of continual research to solve the above-mentioned problems, the present inventors have conventionally made soluble keratin contact α-keratin with sodium thioglycolate in the presence of water, and then added an oxidizing agent to this treatment liquid. In the presence of thioglycolic acid and the like contained in this reaction system, some -SH groups in solubilized keratin are rapidly oxidized to cysteic acid by the action of oxygen, and disulfide is prepared. It was found to inhibit the (-SS-)-sulfide (-SH) exchange function.

  Then, in the production process of solubilized keratin, it was found that if thioglycolic acid or the like is removed and the oxidation process is prevented, a solubilized keratein having a disulfide-sulfide exchange function can be obtained, and the present invention has been completed.

That is, the present invention is a soluble keratein obtained by the following steps.
(1) In the presence of water, α-keratin is added with thioglycolic acid or a salt thereof to have a pH of 9 to
After reducing at 13.5, the insoluble residue is filtered off to obtain a filtrate. (2) The obtained filtrate is adjusted to pH 2.5-7, and the resulting precipitate is recovered and washed with water. (3) The collected precipitate is dissolved in an alkaline solution having a pH of 9 to 12, and thioglycolic acid or a salt thereof is added under inert conditions. (4) The reaction solution is adjusted to pH 4 to 7, and the resulting precipitate is filtered. Take and wash with water to obtain solubilized keratein.

  Moreover, this invention is a manufacturing method of the soluble keratein containing the process of said (1)-(4).

  Furthermore, this invention is a composition containing the said soluble keratein.

  The soluble keratein of the present invention has almost no —SS— bond specific to keratin, and conversely has —SH bond. And as shown in the below-mentioned Example, this thing can be preserve | saved by means, such as a simple sealing, For example, it can utilize as a compounding component of the composition for hair.

The electrophoresis pattern of keratein prepared by changing raw material keratin (wool), CMADK and re-reduction hydrolysis time is shown. In the figure, M: molecular weight marker, a: wool, b: CMADK, c: re-reduction hydrolysis time 1h, d: 3h, e: 6h, f: 9h, g: 12h, h: 15h, i: 24h . The Raman spectra of raw keratin (wool) and soluble keratin with different re-reduction hydrolysis times are shown. In the figure, a: raw wool, b: re-reduction hydrolysis time 1h, c: 3h, d: 6h, e: 9h, f: 12h, g: 15h, h: 24h. The figure which shows the result of the wet heat permanent of Example 2. FIG. A shows the state immediately after processing, and B shows the state after shampooing 10 times. FIG. 6 is a view showing the result of a straight perm of Example 6. FIG. In the figure, the state before treatment is shown in A, and the state after shampooing 10 times after straight perm treatment is shown in B. Further, the hairs in the figure are in the order of low damage perm hair, high damage perm hair, and peculiar hair from the left.

  The soluble keratein of the present invention is obtained by a method including the steps (1) to (4). That is, α-keratin that is insoluble in water is brought into contact with sodium thioglycolate in the presence of water without using a protein denaturant, and then the obtained treatment solution is subjected to several stages of pH adjustment and filtration steps It is obtained by going through.

  In order to produce soluble kerate from α-keratin, it is first contacted with thioglycolic acid or a salt thereof (hereinafter referred to as “thioglycolic acid”) in the presence of water to reduce α-keratin, and then obtained. The treated solution containing reduced α-keratin (keratein) is subjected to solid-liquid separation, and the insoluble residue is removed by filtration to obtain a filtrate (step (1)).

  Examples of α-keratin (keratin fiber) that is a starting material for producing the soluble keratein of the present invention include animal hair, human hair, hooves, horns, and nails. Among these, the animal hair is not particularly limited, and examples thereof include wool such as merino and lincoln.

  This α-keratin is preferably subjected to pretreatment such as washing with a neutral detergent, washing with water, and air drying, and may be used after cutting or pulverizing if necessary.

For the reduction of α-keratin, thioglycolic acid is used, which is a compound represented by HS—CH ₂ COOM (where M represents a hydrogen atom or an alkaline counter ion). Among these, examples of the salt of thioglycolic acid include sodium thioglycolate, potassium thioglycolate, lithium thioglycolate, and ammonium thioglycolate.

The reduction of α-keratin (Kr—CH ₂ —SS—CH ₂ —Kr; where Kr represents a partial structure of α-keratin; the same applies hereinafter) is brought into contact with thioglycolic acid in the presence of water. Therefore, an aqueous solution in which thioglycolate is dissolved in water may be used, or an aqueous solution in which thioglycolic acid (HS—CH ₂ COOH) and a base are dissolved in water may be used.

  This reduction operation is performed by immersing α-keratin in an aqueous solution containing the above thioglycolic acid, stirring and shaking. The pH of the aqueous solution at that time is the reduction reaction of α-keratin by thioglycolic acid. Is preferably in the range of 9 to 13.5. In order to adjust the pH within this range, it is preferable to add an alkali agent to the aqueous solution as necessary. The alkaline agent to be added is not particularly limited, but it is preferable to use lithium hydroxide, potassium hydroxide, sodium hydroxide, ammonium hydroxide or the like alone or in combination of two or more. In addition, when reducing α-keratin with an aqueous solution in which thioglycolic acid and a base are dissolved, it is preferable to use sodium hydroxide as an alkaline agent that is a base.

  The amount of thioglycolic acid used in the above reduction reaction is preferably 0.005 to 0.02 mol, particularly preferably 0.0075 to 0.01 mol, with respect to 1 g of α-keratin. Further, when viewed as the molar concentration of thioglycolic acid contained in the aqueous solution, it is not particularly limited, but is preferably 0.1 to 0.4M, more preferably 0.15 to 0.2M. preferable. The amount of the aqueous solution used is preferably 20 to 200 times (bath ratio) in volume ratio to 1 g of α-keratin.

Within the above range, almost all disulfide bonds (SS bonds) contained in α-keratin are reduced and converted into sulfhydryl groups (SH groups), so soluble keratein (HS—CH ₂ —Kr) and Kr It becomes a compound represented by —CH ₂ —SS—CH ₂ COOH (CMADK). In order to utilize the excess of thioglycolic acid in the above reaction, in addition to the above _{compounds, HOOCCH 2 -SS-CH 2 COOH} ( dithiodiglycolic acid; DTDG) also by-produced.

  The temperature in the reduction is preferably 20 to 50 ° C. If the treatment temperature is too low, the reduction rate of the SS bond decreases, and α-keratin may not be sufficiently reduced. On the other hand, if the treatment temperature is too high, the keratin chain molecule of α-keratin may be cleaved and the protein may be decomposed. Moreover, although processing time changes also with process temperature, the range for 20 minutes-5 days is preferable. If the treatment time is insufficient, the degree of reduction decreases, and some SS bonds may not be converted to sulfhydryl groups. Therefore, in order to reduce almost all SS bonds contained in α-keratin and avoid protein degradation, for example, when the treatment temperature is 20 ° C., the treatment temperature is about 3 to 5 days, and the treatment temperature is 25 ° C. In this case, it is preferable to set the processing time according to the processing temperature, such as about 48 hours, and when the processing temperature is 50 ° C., about 20 minutes to 4 hours.

  Since the treatment liquid obtained by such reduction contains non-keratin proteins and the like as insoluble residues, it is necessary to remove them by solid-liquid separation. This solid-liquid separation can be performed by a known method such as filtration, centrifugation, decantation or the like. When solid-liquid separation is performed by a filtration method, for example, it is preferable to use a filter paper of about No. 2 (retained particle diameter 5 μm) manufactured by Toyo Roshi Kaisha.

  The insoluble matter or precipitate filtered off by the solid-liquid separation is further added with an alkaline solution having a pH of about 11, and the extracted and solid-liquid separated solution is separated from the solid-liquid separated solution. You can meet them.

  The filtrate obtained by the above step (1) is then adjusted to an acidity of about pH 2.5-7, preferably about pH 4, and the resulting precipitate is recovered and washed with water (step (2)).

  This step is a step of precipitating soluble keratein or CMADK dissolved in the filtrate as a solid, and separating and purifying it from the remaining thioglycolic acid or its dimer DTDG. This precipitation may be natural precipitation, but in order to precipitate efficiently, use such as centrifugation is preferred.

  As a specific recovery method, a method of adding an acid to the filtrate obtained in the above step (1) to adjust its pH to about 2.5 to 7 and decanting, filtering or centrifugally depositing the resulting precipitate. Is exemplified. The pH adjustment at this time is preferably performed by adding an acid such as hydrochloric acid or acetic acid or a salt thereof. When hydrochloric acid is used as the acid, the molar concentration is preferably about 0.05M to 0.1M, and when acetic acid is used, the molar concentration is preferably about 0.5 to 1M.

  The precipitate obtained by the pH adjustment is preferably washed using an acetic acid aqueous solution or a hydrochloric acid aqueous solution having a pH of 3 to 4. In addition, it is more preferable to use an acetic acid aqueous solution in that this cleaning does not generate hydrochloric acid gas.

  The precipitate collected in the step (2) is then dissolved in an alkaline solution having a pH of 9 to 12, and thioglycolic acid is added to the solution under inert conditions (step (3)).

  This step is a step in which the solidified CMADK is dissolved again in an alkaline solution and reduced again with thioglycolic acid under the condition that oxygen in the air does not influence to form soluble keratein.

  In this step, for example, the precipitate collected in the step (2) with stirring in an aqueous solution having a pH of 9 to 12, preferably 10.5 to 12, with sodium hydroxide, potassium hydroxide, etc. ( Soluble keratin or CMADK) is dissolved so as to be about 1 to 5% by mass (hereinafter referred to as “%”), and then 5 to 15% with respect to 1% by weight of the precipitate under the condition of nitrogen substitution. It is carried out by adding about twice as much aqueous solution of thioglycolic acid.

  This reaction using thioglycolic acids is preferably carried out under substitution of an inert gas such as nitrogen or argon gas, or under conditions in which a small amount of these inert gases are passed, and the reaction temperature is preferably about room temperature.

  The keratin protein is composed of an intermediate filament protein (IFP; about Mw 50,000) and a keratin-associated protein (KAP; Mw 22,000 to 10,000), and the soluble keratein of the present invention includes a raw material keratin and There are high-molecular-weight soluble kerateins consisting of IFP and KAP having the same molecular weight, and low-molecular-weight soluble kerateins obtained by further hydrolyzing IFP and KAP. These soluble kerateins can be produced by adjusting the reaction time in the above step (3). That is, by setting the reaction time to about 0.5 to 3 hours, the polymer-soluble keratein having an average molecular weight of about 65,000 to 14,000 has an average reaction time of about 6 to 24 hours. A low molecular weight soluble keratein having a molecular weight of about 45,000 to 5,000 is obtained.

  In the above reaction, CMADK is reduced with thioglycolic acid to produce soluble keratein and DTDG. However, since the reaction is performed under inert conditions, the dimerization reaction between thioglycolic acids does not occur. The amount of DTDG in the system can be reduced.

  Finally, the pH of the reaction solution in the above step (3) is adjusted to 2.5 to 7, preferably 4 to 7, and the resulting precipitate is collected by filtration and washed with water to obtain the desired solubilized keratin. Yes (step (4)).

  This step is a step in which soluble keratein in the reaction system is solidified and separated from other substances such as thioglycolic acid or DTDG.

  Specifically, in step (4), an acid solution such as 1M hydrochloric acid is added to the reaction solution in step (3) to lower the pH to near neutrality, and then the pH is adjusted to 4 with a solution such as 25% acetic acid. It is carried out by precipitating soluble keratein to about ˜7, then washing it with water and removing thioglycolic acids and DTDG as contaminants.

  In this way, soluble keratein is obtained as a paste having a pH of 5 to 6, which may be stored as it is as a powder that has been refrigerated, frozen, or lyophilized. However, it is more preferable that after dehydration, it is placed in a lower alcohol such as ethanol, the remaining water is replaced with ethanol, and then stored as a dried product from which ethanol or the like is removed.

  The solubilized keratin of the present invention can be stored in a hermetically sealed package that prevents contact with air. However, when the storage is for a long period of time, it is preferable to add a preservative such as methylisothiazolineone. In addition, the soluble keratein of the present invention is preferably stored frozen in view of preventing light deterioration and heat deterioration, and more preferably stored in a sealed container.

  For example, the CMADK content in the soluble keratein of the present invention is 1% or less, and the DTDG content is 1% or less. And, for example, even when a 5% aqueous solution of this product is left in the atmosphere for one week, the residual rate remains 70% or more.

  The soluble keratein obtained as described above can be used for various applications, and preferred examples thereof include general hair care agents such as hair sprays, hair liquids and hair creams, and hair compositions such as permanent wave agents. Products, eyelash compositions, and nail compositions.

  In this hair composition, components other than the above-mentioned non-modified soluble keratein can be appropriately blended according to the purpose of use. Such known hair composition materials include surfactants such as anionic surfactants, cationic surfactants, amphoteric surfactants and nonionic surfactants; hydroxys such as higher alcohols, lower alcohols and polyhydric alcohols. Compounds; oily components such as fats and oils, ester oils, fatty acids, hydrocarbons, waxes; polymer components such as synthetic polymer compounds, semi-synthetic polymer compounds, natural polymer compounds, and saccharides. Examples of other known hair composition materials include silicones, proteins, amino acids, animal and plant extracts, microorganism-derived materials, inorganic compounds, fragrances, preservatives, and sequestering agents.

  Among the above surfactants, anionic surfactants include, for example, N-acyl amino acid salts, alkyl ether carboxylates, fatty acid amide ether carboxylates, fatty acid amide ether carboxylic acids, acyl lactates, alkane sulfonic acids. Salt, α-olefin sulfonate, alkyl sulfosuccinate, alkyl sulfoacetate, alkylbenzene sulfonate, alkylnaphthalene sulfonate, alkyl sulfate, alkyl ether sulfate, fatty acid monoglyceride sulfate, alkyl phosphate, poly Anionic surfactants such as oxyethylene alkyl ether phosphates; for example, alkylamine salts, fatty acid amidoamine salts, ester-containing tertiary amine salts, arkobelle type tertiary amine salts, long-chain alkyltrimethylammonium salts, di-long-chain alkyldimethyls Cationic surfactants such as ammonium salts, tri long-chain alkyl monomethyl ammonium salts, benzalkonium type quaternary ammonium salts, monoalkyl ether type quaternary ammonium salts; for example, alkyl glycine salts, carboxymethyl glycine salts, N-acylaminoethyl -N-2-hydroxyethylglycine salt, alkylpolyaminopolycarboxyglycine salt, alkylaminopropionate, alkyliminodipropionate, N-acylaminoethyl-N-2-hydroxyethylpropionate, alkyldimethylaminoacetic acid Betaine, fatty acid amidopropyldimethylaminoacetic acid betaine, alkyldihydroxyethylaminoacetic acid betaine, N-alkyl-N, N-dimethylammonium-N-propylsulfonate, N-alkyl-N, N- Amphoteric surfactants such as dimethylammonium-N- (2-hydroxypropyl) sulfonate, N-fatty acid amidopropyl-N, N-dimethylammonium-N- (2-hydroxypropyl) sulfonate; Ethylene alkyl ether, polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol tetra fatty acid ester, glycerin fatty acid ester, sorbitan fatty acid ester, polyglycerin fatty acid ester, sucrose fatty acid Nonionic surfactants such as esters are exemplified. These surfactants can be used alone or in combination of two or more.

  Examples of the hydroxy compound that can be incorporated into the hair composition include higher alcohols such as cetanol, isocetyl alcohol, stearyl alcohol, isostearyl alcohol, behenyl alcohol, octyldodecanol, and myristyl alcohol; for example, ethanol and isopropyl alcohol. Lower alcohols; for example, polyhydric alcohols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, glycerin, diglycerin, and butylene glycol. These hydroxy compounds may be used alone or in combination of two or more.

  Furthermore, examples of the oily component that can be blended in the hair composition include almond oil, avocado oil, olive oil, shea fat oil, evening primrose oil, camellia oil, peanut oil, rosehip oil and the like; for example, ethyl oleate, myristic acid Isopropyl, isopropyl palmitate, butyl stearate, cetyl palmitate, myristyl myristate, octyldodecyl myristate, isopropyl isostearate, ethyl isostearate, cetyl 2-ethylhexanoate, hexyl isostearate, ethylene glycol di-2-ethylhexanoate , Ethylene glycol dioleate, propylene glycol di (capryl / capric acid), propylene glycol dioleate, trimethylolpropane triisostearate, tetra-2-ethylhexanoic acid Ester oils such as taerythritol, isocetyl isostearate, 2-octyldodecyl dimethyloctanoate, myristyl lactate, trioctyldodecyl citrate, diisostearyl malate, di-2-ethylhexyl succinate, diisobutyl adipate, cholesteryl stearate; Fatty acids such as isostearic acid, oleic acid, capric acid, stearic acid, palmitic acid, hydroxystearic acid, behenic acid, myristic acid, lauric acid, lanolin fatty acid, linoleic acid; eg liquid paraffin, squalane, pristane, ozokerite, paraffin, ceresin , Hydrocarbons such as petroleum jelly and microcrystalline wax; for example, waxes such as beeswax, mole, candelilla wax and carnauba wax. These oil components can also be used alone or in combination.

  Furthermore, examples of the polymer component that can be blended in the hair composition include synthetic polymer compounds such as carboxyvinyl polymer, polyvinyl alcohol, polyvinylpyrrolidone, polyacrylic acid, methacryloylethylbetaine / methacrylic acid ester copolymer; For example, semi-synthetic polymer compounds such as methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose, and soluble starch; for example, natural polymer compounds such as sodium alginate, guar gum, glucan, cellulose, sodium hyaluronate, and the like. These polymer components may be used alone or in combination of two or more.

 Furthermore, examples of the saccharide that can be blended in the hair composition of the present invention include sorbitol, mannitol, glucose, fructose, xylitol, lactose, maltose, maltitol, trehalose, and the like. It can mix | blend with a hair treatment agent.

  The composition for hair of this invention is prepared by combining the soluble keratein of this invention with the said arbitrary component according to the use, and preparing it.

  The form of the hair composition is not particularly limited, and examples thereof include liquid, emulsion, lotion, cream, wax, gel, solid, foam (foam), and mist.

  The pH of the hair composition is not particularly limited, but is preferably 5.0 or more and 11.0 or less, preferably 6.0 or more and 10.0 or less, more preferably 6.5 or more and 9.0 or less, and 6 It is particularly preferably from 0.5 to 8.0. If the pH is less than 5.0, precipitation may occur, and if the pH is 11.0 or more, soluble keratein may be hydrolyzed.

  Next, some preferred embodiments of the hair composition of the present invention will be described.

  As an example of the preferable aspect of this invention hair composition, a heating type permanent wave agent can be mentioned. In this permanent wave agent, the composition is first applied to the hair, then given a desired shape to the hair, heated to an appropriate temperature, and held for an appropriate time to maintain the desired shape. is there.

  This permanent wave agent is preferably in the form of a solution, dispersion liquid or paste that can be easily applied to hair, and contains, for example, a solvent in addition to soluble keratein.

  The permanent wave agent is used, for example, by applying an appropriate amount to the hair after shampooing, then adjusting the hair to a desired shape with a curler or a brush, and then heating.

  This heating is generally at a temperature of 100 ° C. or less, preferably about 40 ° C. to 70 ° C., and the heating time is also generally about 3 to 20 minutes, preferably about 5 to 15 minutes. If the temperature and the heating time are in this range, the desired shape can be stably maintained without damaging the hair.

  Moreover, it is also possible to use a hair iron for heating, and if a round iron is used, a desired hair shape such as a wave hair can be formed, and if a flat iron is used, a desired hair shape can be formed. The heating temperature at this time is about 50 ° C. to 140 ° C., preferably about 80 ° C. to 130 ° C. The heating time is generally within 30 seconds when using a round iron, and when using a flat iron Is about 1 to 5 reciprocations, preferably about 5 to 15 minutes, while heating while moving one place within 5 seconds. If the temperature and the heating time are in this range, the desired shape can be stably maintained without damaging the hair.

  Furthermore, the hair can be heated by, for example, spraying warm air on the hair with a dryer or the like, or applying a heating element (such as curler) having an electric heater or the like to the hair.

  In addition, since the solubilized keratein of the present invention has an unmodified sulfhydryl group, the binding property to the sulfhydryl group in hair is high. Therefore, permanent hair can be appropriately imparted to virgin hair that has not been subjected to permanent treatment or coloring treatment, even to hair that has been subjected to permanent treatment or coloring treatment (coloring, decolorization, etc.) in the past.

  The hair composition of the present invention may be in the form of a general hair care agent such as a hair spray, a hair liquid, a hair cream, or the like, and may also be a two-component cold permanent agent.

  Furthermore, as another example of the use of the soluble keratin of the present invention, a composition for eyelashes, such as applying to a eyelash as a eyelash cosmetic liquid and applying a permanent curl with a hot eyelasher, or applying to a nail, a nail strengthening agent And nail compositions used as coating agents.

Action

  The soluble keratein of the present invention has an SH group generated by cleaving a disulfide (—SS—) bond of keratin by allowing thioglycolic acid to act on α-keratin, and cleaving this disulfide bond. In addition, the soluble keratein of the present invention substantially eliminated CMADK and DTDG that could not be removed by the conventional method of producing soluble keratin. It is possible to maintain a stable state even in the presence of.

  EXAMPLES Next, although an Example is given and this invention is demonstrated in more detail, this invention is not restrict | limited at all by these Examples.

Example 1
(1) Reduction reaction (synthesis of CMADK)
20 L of 0.4 M sodium thioglycolate solution adjusted to pH 11 with sodium hydroxide solution is placed in a chemical enamel tank that is a reaction vessel, and 1 kg of wool is put therein. The reaction was conducted while stirring for 24 hours in an open system at a reaction temperature of 30 ° C.

  After completion of the reaction, the reaction solution is filtered using water-resistant filter paper (126-3; manufactured by ADVANTEC) to obtain a filtrate. On the other hand, the residue on the filter paper is transferred to a beaker, and a pH 11 NaOH solution is added thereto and stirred. The NaOH solution is about 5 times the residual 1 (bath ratio 5) and stirred for about 15 minutes. The NaOH solution from the residue is then centrifuged and the solution portion is recovered. This step is performed once or twice, and the recovered liquid obtained is added to the first filtrate.

(2) CMADK recovery and purification The filtrate obtained in (1) above was neutralized by adding a 6M-HCl aqueous solution. When the pH of the filtrate reached 7, it was replaced with 1M HCl solution and further lowered to pH 4. At this time, the solution became turbid as the pH decreased, and as the pH approached 4, precipitation occurred.

  The produced precipitate was recovered by decantation to obtain CMADK as a solid substance. For separation of the precipitate, solid-liquid separation processing such as filtration and centrifugation other than decantation may be used. The resulting CMADK precipitate is washed with water 2 to 3 times to purify unreacted thioglycolic acid (TGA) and dithiodiglycolic acid (DTDG) which is an oxidized dimer.

(3) Synthesis of soluble keratein (WK) CMADK obtained in (2) was neutralized and dissolved using a 25% NaOH solution. When the pH exceeded 7, it was replaced with dilute NaOH solution and the pH of this solution was adjusted to 11.

  Next, the concentration of the solution was adjusted so that the concentration of CMADK was 2 to 3%, and a reduction reaction was performed by adding 6-fold amount of 0.2M-TGA solution as a reducing agent to CMADK1. This reaction was performed with the solution replaced with nitrogen gas, and the reaction temperature was room temperature. Instead of nitrogen gas replacement, the reaction may be performed while flowing a very small amount of nitrogen gas.

  As shown in FIG. 1, in the above reaction, when the reaction time is 1 hour, the molecular weight is about 51 kDa and 65 kDa, two bands based on IF protein, and the molecular weight is 22 kDa to 10 kDa and has a high molecular weight band caused by KAP. WK was obtained. Further, by setting the reaction time to 12 hours, the IF protein and KAP bands were hydrolyzed to obtain a low molecular weight WK having a molecular weight of 45,000 to 5,000 in which the respective proteins were mixed.

FIG. 2 shows a Raman spectrum representing the relationship between the hydrolysis time of soluble keratein and the sulfhydryl group. The Raman shift near 550 cm ⁻¹ due to the disulfide group stretching vibration observed in the raw wool was not observed in WK, and a shift due to the sulfhydryl group stretching vibration was observed near 2600 cm ⁻¹ . The intensity of the sulfhydryl group was strongest at 1 h, and the peak intensity gradually decreased after 6 h.

(4) Recovery and washing of WK The pH of each WK solution obtained in (3) above was lowered to around pH 7 using a 6M-HCl solution. The pH was then lowered to 4 using a 25% acetic acid solution. The WK precipitated by this pH adjustment was washed with water 2-3 times to adjust the pH to 5-6.

  The resulting WK precipitate was lightly dehydrated by filtration or centrifugation, and then placed in 75% ethanol and replaced for 15 minutes. Subsequently, ethanol was removed by filtration or centrifugation, and each WK was sealed in a gas barrier bag. The ethanol may be removed by centrifugation, and WK is preferably refrigerated in the dark.

Example 2
Wet heat perm (1)
The low molecular weight WK obtained in Example 1 is dissolved in purified water so as to have a concentration of 1%, 1.5% and 2%, sodium carbonate is added to this solution, and the pH is adjusted to 10 to obtain a permanent wave composition. Adjusted.

  Wrapped shampooed middle damaged hair or damaged hair around a rod having a diameter of 10 mm, coated with the above permanent wave composition, heated with the following heating pattern, and then commercially available oxidizing agent (bromic acid) using bromic acid. (Concentration 5%) for 5 minutes. Next, rinsing was performed for 30 seconds, followed by natural drying. The result is shown in FIG. 3 (the state immediately after the treatment is A, and the state after shampooing 10 times is B).

[Heating pattern]
The temperature is raised from 20 ° C. to 55 ° C. at a rate of 5 ° C./min. After reaching 55 ° C., the temperature is kept at this temperature for 3 minutes. The total heating time is 10 minutes.

  As a result, it was clarified that wave formation is possible only with 1% of low molecular weight WK.

Example 3
Wet heat perm (2)
A wet heat perm was performed in the same manner as in Example 2 except that the low molecular WK was replaced with the polymer WK obtained in Example 1.

  As a result, it has been clarified that wave formation is possible with only 1.5% of the polymer WK, although the wave shape is gentler than that of the low molecular WK.

Example 4
Wet heat perm (3)
The polymer WK obtained in Example 1 was dissolved in purified water so that its concentration was 1.5% and cysteamine was 1.0%, and the pH of this solution was adjusted to 10 with sodium carbonate. A permanent wave composition was prepared.

  Each of the middle damaged hair and damaged hair shampooed in advance is wound around a rod having a diameter of 11 mm, this permanent wave composition is applied, heated with the following heating pattern, rinsed for 30 seconds, and then brominated acid is used. The resulting product was treated with a commercially available oxidizing agent (bromic acid concentration 5%) for 5 minutes. Furthermore, it rinsed for 30 second and performed natural drying.

[Heating pattern]
The temperature is raised from 20 ° C. to 55 ° C. at a rate of 5 ° C./min. After reaching 55 ° C., the temperature is kept at this temperature for 3 minutes. The total heating time is 10 minutes.

  As a result, it was clarified that when 1.5% of the polymer WK was added, the wave forming ability was improved as compared with the case treated with only 1% cysteamine, and the durability of the wave was improved even after 10 shampoos. .

Example 5
Wet heat perm (4) A wet heat perm was performed in the same manner as in Example 4 except that the polymer WK was replaced with the low molecular weight WK obtained in Example 1.

  As a result, when 1.5% low molecular weight WK is added, the wave forming ability is improved compared to the case treated with only 1% cysteamine, and the durability of the wave is improved even after 10 shampoos. It became clear that it was higher than WK.

Example 6
Straight Perm The low molecular weight WK obtained in Example 1 was dissolved in purified water to a concentration of 2.0%, and the pH of this solution was adjusted to 10 with sodium carbonate to prepare a composition for straight perm.

  This straight perm composition is applied to pre-shampooed low-damaged hair, high-damaged hair, and peculiar hair (low-damaged hair and high-damaged hair are Japanese perm-treated hair, and peculiar hair is Indian hair (Bulux Co., Ltd.)). The product was applied, treated 5 times with a straight iron at 130 ° C., and then treated for 5 minutes with a commercially available oxidizing agent using bromic acid (5% bromic acid). Next, rinsing was performed for 30 seconds, followed by natural drying. The result is shown in FIG. 4 (the state before treatment is A, and the state after shampooing 10 times after treatment is B).

  As a result, it has been clarified that the treatment with a composition containing only 2% of low molecular weight WK has a high effect of changing wave permanent hairs and peculiar hairs straight.

Example 7
Straight Perm A straight perm was performed in the same manner as in Example 6 except that the low molecular WK was replaced with the polymer WK obtained in Example 1.

As a result, it has been clarified that only the polymer WK 2% can change the wave perm hair and the peculiar hair straight.

Claims (7)

Next step,
(1) In the presence of water, α-keratin is added with thioglycolic acid or a salt thereof to have a pH of 9 to
After reducing at 13.5, the insoluble residue is removed by filtration to obtain a filtrate. (2) The obtained filtrate is adjusted to pH 2.5-7, and the resulting precipitate is collected and washed with water. (3) The collected precipitate is dissolved in an alkaline solution having a pH of 9 to 12, and thioglycolic acid or a salt thereof is added under inert conditions. (4) The reaction solution is adjusted to pH 4 to 7, and the resulting precipitate is filtered. Soluble keratein obtained by taking and washing with water to obtain solubilized keratein.   The soluble keratein according to claim 1, wherein the reduction in step (1) is carried out at 20 to 50 ° C.   The soluble keratein according to claim 1 or 2, wherein the dissolution in the step (3) dissolves the precipitate recovered in the step (2) so as to become a 1 to 5% by mass solution.   The soluble kerate according to any one of claims 1 to 3, wherein the content of carboxymethylalanyl disulfide keratin and dithiodiglycolic acid is 1% or less, respectively. Next step,
(1) In the presence of water, α-keratin is added with thioglycolic acid or a salt thereof to have a pH of 9 to
After reducing at 13.5, the insoluble residue is removed by filtration to obtain a filtrate. (2) The obtained filtrate is adjusted to pH 2.5-7, and the resulting precipitate is collected and washed with water. (3) The collected precipitate is dissolved in an alkaline solution having a pH of 9 to 12, and thioglycolic acid or a salt thereof is added under inert conditions. (4) The reaction solution is adjusted to pH 4 to 7, and the resulting precipitate is filtered. A method for producing soluble keratein, which comprises taking, washing and obtaining solubilized keratein.   A composition containing the soluble keratein according to any one of claims 1 to 4. The composition according to claim 6, which is a composition for hair, a composition for eyelashes or a composition for nails.