JPS63301809A - Water-soluble keratin, its production and hair cosmetic containing same - Google Patents

Abstract

PURPOSE:To easily obtain water-soluble keratin suitable as a raw material for hair-cosmetic, preventing the gelatinization in a process for removing a reducing agent, by reducing a keratin-containing substance in a liquid medium and adding a surfactant to the resultant keratin solution. CONSTITUTION:A keratin-containing substance such as fur of goat, sheep, horse, pig, rabbit, etc., or feather of various birds is reduced to obtain a water-soluble keratin having a high mol.wt., free from irreversibly denaturated disulfide bond and suitable as a raw material for hair-cosmetic. In the above process, a surfactant (preferably an anionic surfactant having high solubility in water even at a high salt concentration) is added to a solution produced by reducing the keratin-containing substance in a liquid medium and removing insoluble materials from the product. The reducing agent is removed from the mixture e.g. by dialysis to effect complete desalting and purification of the keratin solution without causing clouding and precipitation and obtain a water-soluble keratin which can be easily dissolved in water even after drying.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention provides a water-soluble keratin whose disulfide bonds are not irreversibly denatured and which has a high molecular weight and is suitable for hair products, and a method for producing the same. The present invention relates to hair cosmetics containing the present invention.

[Conventional technology]

It has been known that keratins, which exist in large amounts in tissues such as hair, animal hair, feathers, horns, nails, and hooves, are useful as raw materials for hair cosmetics. However, keratin, which is a type of structural tanno-Q substance, is insoluble or sparingly soluble in ordinary solvents, and therefore cannot be used without extensive decomposition or modification treatment. In other words, a hydrolyzate obtained by a combination of hydrolysis with a concentrated acid or alkali, reduction treatment, and hydrolysis with a tannolyte-degrading enzyme of the above-mentioned keratin-containing natural product: Keranaine derivatives are obtained by reductive cleavage of thiol groups, followed by chemical modification with monoiodoacetic acid or N-ethylmaleimide to prevent recombination of the thiol groups; or keranaine derivatives obtained by oxidative decomposition of disulfide bonds with an oxidizing agent to form sulfonate salts. It is used in the form of keradose obtained from Shikoto K.

[Problem that the invention seeks to solve]

However, the above-mentioned keratin hydrolyzate has a problem in that, because of its small molecular weight, it has a low conditioning effect in imparting shine and body to the hair. In addition, although the molecular weight of keranine derivatives and keradose is close to that of the original keratin, the disulfide bonds characteristic of keratin are irreversibly denatured, so exchange reactions with thiol groups/zosulfide bonds in hair cannot be expected. However, it has the problem that it easily detaches from the hair.

Therefore, in order to obtain high-molecular-weight keratin without damaging disulfide bonds, a solubilizing agent consisting of a reducing agent such as thioglycolic acid and a phosphorus and phosphor modifier such as urea is added to the raw keratin-containing material in a highly alkaline manner. After reducing and solubilizing the material, it is carried out to remove the solubilized gold by performing treatments such as dialysis and ultrafiltration. However, with this method, it is extremely difficult to sufficiently remove the solubilizer while leaving the keratin in a dissolved state. In other words, the mechanism of solubilization of keratin by reducing agents is understood to be due to the cleavage of disulfide bonds in keratin and conversion into thiol groups. When the agent is eluted into the external dialysis fluid, the keratin in the internal fluid becomes insoluble again.
It aggregates and gradually turns into a gel.

In order to solubilize this dull keratin, the above-mentioned solubilizing agent must be added again. As a method to prevent dalification during dialysis, a method has been proposed that uses water to which polyhydric alcohol such as glycerin has been added as the external dialysis fluid (
JP-A-53-121800), but even this method had little effect on materials that are difficult to solubilize in 9, such as wool.

[Means to solve the problem At]

Therefore, the present inventor effectively removed the solubilizing agent from the keratin aqueous solution while completely preventing gelation.
We conducted extensive research to develop a method for producing keratin gold that can be easily dissolved in water even after dry recovery, and found that after adding a surfactant to a keratin solution obtained by reducing keratin material in a liquid medium. The inventors have discovered that the above object can be achieved by removing the solubilizing agent by isobaric dialysis, and have completed the present invention.

That is, the present invention provides a water-soluble keratin obtained by reducing a keratin-containing substance in a liquid medium, then adding a surfactant to the solution from which insoluble matter has been removed, and then removing the reducing agent, a method for producing the same, and a method for producing the same. The present invention provides a hair cosmetic containing the following.

The keratin-containing substance used in the present invention may be any substance containing true keratin, such as goat, sheep, horse,
Hair of pigs, cows, rabbits, etc., and feathers of various birds are preferably used.

Further, as the reducing agent, for example, thiol derivatives such as thioglycolic acid and mercanotoethanol; phosphorus-containing compounds such as tripelphosphine and triphenylphosphine; or hydrogen sulfite, etc. are used.

These reducing agents are keratin-containing substances 10? 0 for
．． 01 to 0.5 mol is used, but from the viewpoint of reduction reaction efficiency and economical efficiency, 0.0 mol is used for the keratin-containing material 102.
It is preferable to use 5 to 0.25 mol.

The reduction treatment is carried out in a liquid medium that is stable against reduction of water, alcohols, amides, etc. and has an affinity for keratin-containing substances. The amount of liquid medium needs to be in excess so that the keratin-containing material is completely immersed, but from the viewpoint of subsequent handling, it is preferably 10 to 40 times the weight of the keratin-containing material.

Furthermore, animal hair, hair, horns, nails, hooves, etc., may not have sufficient solubility in liquid media even if disulfide bonds are cleaved due to secondary bonds such as hydrogen bonds and salt-forming bonds. In such a case, add tanno-Q quality modifiers such as urea and thiourea; alcohols such as methanol, ethanol, and gulononol; alkalis such as sodium hydroxide and ammonia; zinc chloride and sodium iodide to the liquid medium. It is preferable to use a solution that contains an inorganic salt such as, for example, as a solubilizing agent to impart solubility to the reduced product. The larger the amount of such a solubilizing agent, the more effective it is, but the appropriate amount is determined in consideration of the solubility in the liquid medium and the efficiency of the subsequent removal operation of the reducing agent and the like.

The reduction solubilization reaction is carried out under alkaline conditions, preferably at pH 10.
It is preferable to carry out at 11.

Further, the reaction temperature and reaction time are appropriately adjusted so that the reduction reaction is completely carried out. For example, it is sufficient to carry out the reaction for 3 to 6 hours at room temperature, 24 to 48 hours at 5°C, and 30 minutes to 2 hours at 40 to 60°C.

The keratin solution obtained in this way often contains foreign substances and insoluble components that have adhered to the raw keratin-containing material, so it must be centrifuged or These insoluble substances are removed by filtration.

After removing insoluble matter, the surfactant to be added to the keratin solution should be an anionic surfactant that has good water solubility even under high salt concentrations, such as anionic surfactants. Preferred are sulfuric acid ester salts such as lyoxyethylene alkyl ether sulfates, or sulfonic acid salts such as formalin condensates of naphthalene sulfonic acid.

The amount of surfactant added to the solution is preferably 0.01 to 5% by weight, preferably 0.1 to 2% by weight. The amount added varies depending on the concentration of the keratin solution and the quality of the raw keratin, but adding more than 5% by weight is economically undesirable because it takes effort to remove the excess. By adding this surfactant, the keratin solution is completely desalted and purified without producing any turbidity or precipitation in the subsequent step of removing reducing agents and the like.

The step of removing the reducing agent and the like is carried out by means such as dialysis, electrodialysis, and ultrafiltration until the reducing agent, solubilizing agent, and excess surfactant are completely removed. For example, in dialysis, it is desirable to perform dialysis using 10 times the amount of ion-exchanged water as the keratin aqueous solution at room temperature for one week or more while frequently exchanging the external dialysis solution.

Finally, the obtained keratin solution is dried by freeze drying or the like to obtain the desired water-soluble keratin.

If the keratin concentration may be low, it can be used as is without drying. The keratin obtained as described above is easily dissolved in water, contains 1 to 5 cystines and 0.5 to 3 cystines per 100 amino acid residues, and has an average molecular weight of 30,000 to 70,000. It is a polymeric keratin. The cysteine residues in keratin are gradually oxidized and converted to cystine in an aqueous solution, but this conversion can be prevented by adding an appropriate amount of a reducing agent to the aqueous solution. Further, in an absolutely dry state, cysteine residues are retained without being converted to cystine for a long period of one year or more even at room temperature. In any case, regardless of the degree of this conversion, the keratins of the invention are readily soluble in water.

Hair cosmetics of the present invention include shampoos, rinses, treatments, hair creams, setting lotions, hair solaces, hair liquids, IQ-Manent Wave intermediate treatment agents, and the like. These hair cosmetics are manufactured by known methods. Typical formulation examples are shown in Table 1.

The known ingredients used in these hair cosmetics will be explained below.

(1) Anionic or amphoteric surfactants These are used for the purpose of cleaning the scalp and hair, emulsifying oil, and promoting the penetration of drugs, and include alkyl sulfates, alkyl sulfate ether salts, sulfosuccinate ester salts, etc. Examples include anionic surfactants, imidacillin surfactants, and amphoteric surfactants such as betaine and sulfobetaine. The hydrophobic group is mainly an alkyl group or acyl group having 12 to 14 carbon atoms, and the counter ion used is an alkali metal, an alkanolamine, or the like.

(2) Nonionic surfactants are mainly used for the purpose of emulsifying oil and promoting penetration of drugs, etc. Lyoxyethylene alkyl ether type, fatty acid ester type, ? Examples include liglycerin ether type and ester type surfactants. Hydrophobic groups mainly have 1 carbon number
It is 2 to 14 alkyl groups or acyl groups.

(3) Cationic surfactant Used primarily for hair conditioning, quaternary ammonium salts of the following formula are exemplified.

(In the formula, 1 to 2 of R, , R, , R3 and R4 represent a linear or branched long-chain alkyl group or long-chain hydroxyalkyl group f having 8 to 20 carbon atoms, and the rest represent a long-chain hydroxyalkyl group f having 1 to 2 carbon atoms.
3 alkyl or hydroxyalkyl group or benzyl group, XFi halogen atom or carbon number 1 to 2
(4) Cationic conditioning? Rimer is used primarily for hair conditioning, and includes cationized cellulose (UCC Co., Ltd., ?Rimer JR400, etc.), sialyl quaternary ammonium type ? Examples include rimers (manufactured by Merck & Co., Ltd., Marquat 100.400, etc.).

(5) Amphoteric or nonionic film forming? Rimmer is used primarily for the hair styling effect, and is a lipinylpyrrolidone type, ? Livinyl ether type? Vinyl acetate type? Reacrylic acid type, amphoteric acrylic type, etc.? Rimmer is an example.

(6) Oily substances These are used primarily to condition and add luster to the hair, and include hydrocarbons, higher alcohols, fatty acid esters, lanolins, silicone derivatives, higher fatty acids, fatty acid amides, and the like.

(7) Other substances Humectants such as glycerin and propylene glycol, solubilizers such as ethanol and urea, water-soluble polymers, thickeners such as inorganic salts, other fragrances, pigments, sterilizing preservatives, anti-dandruff agents, Nolizing agents, antioxidants, ultraviolet absorbers, vitamins, hormones, plant extracts, etc. are used as appropriate.

〔Example〕

Next, a more detailed explanation will be given with reference to one example, but the present invention is not limited thereto.Example 1 (Preparation of water-soluble keratin-1) 0,001M ethylene containing urea (8M) Cyaminetetraacetic acid-0,0
To 1200 tons of 2M tris(hydroxymethyl)amine methane buffer (pH 7,4), add 4 liters of waste wool (charcoal noyl).
0f was immersed, degassing, and nitrogen substitution were repeated twice.

Add 2-mercatoethanol 202 under a nitrogen stream,
Subsequently, the pH was adjusted to 10.5 with 10% potassium hydroxide. The nitrogen supply was stopped, and the mixture was stirred at room temperature for 3 hours to carry out a reduction reaction.

After adjusting the pH to 5.0 with 6N hydrochloric acid, 10000r
pnll, centrifuged for 40 minutes at Q°C, 1990t
A supernatant liquid was obtained. To this solution, add tE'lyoxyethylene alkyl ether a tx<Emar 20CM-8,2
After adding 809 (5% product, manufactured by Kao Corporation) and mixing well, the mixture was placed in a cellophane dialysis tube with a diameter of 30/32 inches, and dialyzed for 5 days by flowing ion-exchanged water through the external solution.

As a result, the solubilizing agent was removed and no keratin glue was formed within the dialysis tube.

The dialysis fluid is combined and freeze-dried. 17.6 f of keratin-like keratin was obtained. This keratin was easily dissolved in ion-exchanged water.

Example 2 (Preparation of water-soluble keratin-2) 0.8M potassium thioglycolate aqueous solution (pH 10,5) 300
tK, 1°t of cut wool was added, and the mixture was left at 5°C for 36 hours to carry out a slow reduction reaction. The residue was recovered by vacuum filtration, and immediately poured into 300 tons of ion-exchanged water with stirring. At this time, due to the rapid change in ionic strength, keratin, which has a relatively low sulfur content and a large molecular weight, dissolves into the ion exchange water. Stir at room temperature for 1
After a period of time, a clear liquid was obtained by vacuum filtration.

To this filtrate, 1.5 f of a formalin condensate of sodium naphthalene sulfonate (Demol N1 manufactured by Kao Corporation) was added and dissolved. This solution was dialyzed in the same manner as in Example 1,
A transparent keratin aqueous solution was obtained. The completion of dialysis was monitored by the absorption of the external dialysis fluid (by the naphthalene skeleton). Finally, it was freeze-dried to obtain 3.81 keratin-like keratin. Amino acid analysis of this water-soluble keratin revealed that per 100 amino acid residues, there were 3.32 cysteine and 1.20 cysteine, and the cystine/cysteine content of the polymer fraction of wool tongue and elutrium The acid was retained.

The su obtained in this way? When keratin-like keratin was dissolved in ion-exchanged water to make a 2% solution and cast onto a glass plate or an acrylic plate and air-dried, a film with good film-forming properties and a pencil hardness of 4H or higher was obtained.

Example 3 Chassis compositions shown in Table 2 were prepared by a conventional method, and p
Adjusted to H7.2. All of these shampoos showed good lathering and foam slippage when used, and hair that was washed and dried using these shampoos did not exhibit fried hair, had low combing power, and was particularly excellent in style formation retention. .

Table 2 Similar good results were obtained using the water-soluble keratin obtained in Example 2.

Example 4 A hair rinse shown in Table 3 was prepared, and after adjusting the pH to 5.0, the total amount was adjusted to 100 with water. Hair treated with these rinses had excellent moisturizing and smoothness after drying, and exhibited particularly good style formation retention.

Table 3 Similar results were obtained using the water-soluble keratin of Example 2.

Example 5 The pre-shampoo treatment shown in Table 4 was prepared by adding a water-soluble component heated to the same temperature to an oil-soluble component heated to 70°C, followed by cooling, stirring, and emulsification. The hair treated with these treatments has excellent moisturizing and smoothness after drying, giving it a rating of 4! It showed good style formation retention and the combing force was small.

Example 6 The hair setting agents shown in Table 5 were prepared according to a conventional method. All of these exhibited good set retention power.

Table 5 *Car TF: Gol 941 (Gutdrich) Example 7 The /9-ma intermediate treatment agent shown in Table 6 was prepared according to a conventional method. When this intermediate treatment agent was used on hair treated with the first agent of Q-Ma containing thioglycolic acid, the odor characteristic of No-Ma treated hair was reduced. Also, ・Q-
Damage to hair is reduced and style retention is improved.

Procedural amendment (voluntary) September 16, 1988

Claims (1)

[Scope of Claims] 1. Water-soluble keratin obtained by reducing a keratin-containing substance in a liquid medium, then adding a surfactant to the solution from which insoluble matter has been removed, and then removing the reducing agent. 2. A method for producing water-soluble keratin, which comprises reducing a keratin-containing substance in a liquid medium, adding a surfactant to the solution from which insoluble matter has been removed, and then removing the reducing agent. 3. Hair characterized by containing water-soluble keratin obtained by reducing a keratin-containing substance in a liquid medium, then adding a surfactant to the solution from which insoluble matters have been removed, and then removing the reducing agent. Cosmetics.