Basic amino acid derivative for use as a surfactant, and toiletry or detergent composition containing the same

Abstract: Basic amino-acid derivatives or salts thereof may be obtained by reacting glycidyl ethers with basic amino acids or salts thereof, and are useful as surfactants. When used as surfactants, the compounds of the invention show low irritability towards the skin or mucous membranes, and excellent conditioning effects and therefore can be used in a wide range of toiletry and detergent compositions.

Description: The present invention relates to a basic amino acid derivative suitable for use as a surfactant, in particular for use in a toiletry, detergent or fabric softener composition and the like. Surfactants having low irritability of the skin or the mucous membrane are preferably used in toiletry compositions such as face washes, shampoos, rinses, hair conditioners, body shampoos or the like and in detergent compositions. Further, hair toiletries such as rinses, hair conditioners, hair treatments and the like are expected to have conditioning effects such that these toiletries make the hair smooth and suppress any dry or hard feeling. Known examples of surfactant of low irritability towards the skin or the mucous membrane include acylamino-acid derivatives such as N-acylglutamic acid salts, N-acylglycine salts, N-acylarginine ethyl ester salts and the like. But the above-mentioned acylamino-acid derivatives give the hair low levels of conditioning, and these derivatives are, therefore, not satisfactory as conditioning agents such as rinses, hair conditioners and the like. Besides, with regard to the lathering property, further improvement is required. As another example of surfactant of an amino-acid-derivative type, a surfactant formed by adding a glycidyl ether to a neutral amino acid or an acidic amino acid is known. For example, N-( 3-alkyl-2-hydroxy)propyl-sarcosine and N,N-bis(3-alkyl-2-hydroxy)propyl-glycine formed upon using sarcosine and glycine are described in E. Ulsperger, Fette, seifen, anstrichm., 68 (11), 964 - 967 (1966). Further, N-(3-alkyl-2-hydroxy) propyl-serine, N-(3-alkyl-2-hydrox)propyl-aspartic acid and the like are described in WO-A-94/21595. However, these neutral and acidic amino-acid derivatives still give the hair unsatisfactory conditioning effects. Furthermore, amino-acid derivatives formed by adding a 1,2-epoxyalkane to an amino acid are described in JP-A-22,417/1973. However, these amino-acid derivatives are not said to be satisfactory in terms of a solubility. Meanwhile, alkyl quaternary ammonium salts and the like have been widely used as conditioning agents or fabric softening agents. It is known that these agents are electrically adsorbed on the hair surface which is weakly acidic, or the fabric surface which is charged negatively in the rinsing water, to impart good combing properties, smoothness and the like to the hair, or softness to the fabric. Nevertheless, they strongly irritate the skin, the mucous membrane and the like, and are problematic also in terms of their biodegradability. Further, they lower the hygroscopic property of fabric. Embodiments of the present invention desirably provide a surfactant having low irritability towards the skin, the mucous membrane and the like and which exhibit high solubility and high bubble stability. In a further embodiment a hair toiletry product is provided which desirably exhibits excellent conditioning effects such as imparting smoothness to the hair and suppressing dry or hard feel of the hair. In a still further embodiment a fabric softener is provided which may exhibit excellent softening effect and retention of the hygroscopic properties of fabrics. Under these circumstances, the present inventors have assiduously conducted investigations, and have consequently found that basic amino-acid derivatives formed by reacting glycidyl ethers which are epoxy compounds with basic amino acids such as arginine, lysine and the like can exhibit excellent conditioning effects, softening effects a low level of irritation, an excellent solubility and an excellent bubble stability. These findings have led to the completion of the present invention. The amino-acid derivatives of the present invention can widely be used in toiletry and detergent compositions, and are especially appropriate as hair toiletries such as shampoos, rinses, hair treatments, fabric softeners, and the like. The surfactant of the present invention contains at least one type of the basic amino-acid derivatives represented by formulas (1) to (4) or salts thereof: wherein R 1 to R 6 each represent a linear or branched alkyl or alkenyl group having from 8 to 22 carbon atoms, provided that R 2 and R 3 , or R 5 and R 6 may be the same or different, m represents an integer of from 1 to 5, and X represents any of the following substituents, Salts of the basic amino-acid derivatives include inorganic acid salts such as hydrochloride and sulfate, and organic acid salts such as acetate, citrate, p-toluenesulfonate, fatty acid salt, acidic amino-acid salt and L- or DL-pyrrolidonecarboxylate. These basic amino-acid derivatives or salts thereof may be used either singly or in combination. The basic amino-acid derivatives of formulae (1) to (4) can easily be produced by the same process of reacting an amino acid with an epoxyalkane as described in JP-A-22, 417/1973, namely by reacting a basic amino acid with a glycidyl ether represented by formula (8) wherein R 11 represents a linear or branched alkyl or alkenyl group having from 8 to 22 carbon atoms under alkaline conditions in a lower alcohol or a mixed solvent of a lower alcohol and water. The above-mentioned glycidyl ether can be obtained by reacting, for example, a natural or synthetic saturated or unsaturated higher alcohol with epichlorohydrin. Examples thereof include decylglycidyl ether, dodecylglycidyl ether, tetradecylglycidyl ether and stearylglycidyl ether. These may be used either singly or in combination. Commercially available examples of the glycidyl ether include Epiol L-41 (decylglycidyl ether) and Epiol SK (stearylglycidyl ether) made by NOF CORPORATION, Heloxy 8 (mixture of dodecylglycidyl ether and tetradecylglycidyl ether) made by ACI Japan Ltd., Denacol EX-192 (mixture of dodecylglycidyl ether and tetradecylglycidyl ether) made by Nagase Chemicals, Ltd., and SY-25L (mixture of decylglycidyl ether and dodecylglycidyl ether) made by Sakamoto Yakuhin Kogyo Co., Ltd. Examples of the basic amino acid include arginine, lysine, ornithine, histidine and hydroxylysine. In the case of, for example, lysine and ornithine among the basic amino acids, the binding moiety to the glycidyl ether is considered to be preferentially an ε-amino group (lysine) and a δ-amino group (ornithine). An α-amino group is also available. A compound obtained by reacting two molecules of the glycidyl ether with an ε-amino group, a δ-amino group or an α-amino group is also included therein. Further, a compound obtained by reacting one molecule of the glycidyl ether with each of an ε-amino group (δ-amino group in ornithine) and an α-amino group, and a compound obtained by adding three or four molecules of the glycidyl ether to one molecule of an amino acid may be used. Amino-acid derivatives obtained by reacting a neutral or acidic amino acid with a glycidyl ether are useful as surfactants too. Examples of the neutral amino acid include glycine, alanine, β-alanine, sarcosine, N-methyl-β-alanine, valine, leucine, isoleucine, serine, threonine, methionine, phenylalanine, tyrosine, proline, hydroxyproline, homoserine, α-aminobutyric acid, α-aminovaleric acid, α-aminocaproic acid, phenylglycine, cystine, cysteine, 3,4-dihydroxyphenylalanine and γ-aminobutyric acid. Examples of the acidic amino acid include glutamic acid and aspartic acid. However, these neutral or acidic amino-acid derivatives cannot provide satisfactory conditioning or softening effects. Incidentally, these neutral or acidic amino acid derivatives may be included in compositions of the invention unless the effect of the present invention is impaired. In the reaction between the glycidyl ether and the amino acid, it is advisable to use the amino acid in the form of an alkali metal salt or to conduct the reaction under alkaline conditions in order to increase a reactivity and prevent side reactions. However, with respect to arginine, the reaction could be conducted without using these conditions. As the reaction solvent, a lower alcohol such as methyl alcohol, ethyl alcohol, n-propyl alcohol or i-propyl alcohol, or a mixed solvent of this lower alcohol and water is ordinarily used. The mixing ratio of the lower alcohol to water varies depending on the types of the amino acid and the glycidyl ether. It may be between 100:0 and 10:90, preferably 1:1 to 2:1. When the amount of alcohol is small, the solubility of the glycidyl ether is decreased, and the reaction rate is notably reduced. The reaction temperature varies depending on the type and the composition of the reaction solvent. It is generally between 70°C and 100°C, preferably between 80°C and 95°C. It is advisable that the reaction be conducted under reflux. The glycidyl ether may be added at a time before heating, or in divided portions or dropwise continuously after heating is started. In order to control formation of by-products, it is preferable to add the same dropwise continuously after heating is started. The thus-obtained reaction product sometimes contains, besides the desired amino-acid derivatives, by-products such as unreacted amino acid, glycidyl ether hydrolyzate and the like. In this case, purification can be conducted by known methods such as extraction, recrystallization, chromatography or the like. The resulting product may be used in the form of a mixture unless it influences surface activity. When a higher alcohol is incorporated into the surfactants of the present invention, the hair conditioning effects can further be increased. That is, in preferred embodiments, the present invention provides a toiletry or detergent composition comprising a surfactant of any of formulas (1) to (4) and a higher alcohol. A higher alcohol represented by formula (9) R 12 -OH wherein R 12 represents a linear or branched alkyl or alkenyl group having from 12 to 36 carbon atoms may be employed. Examples thereof which are widely used include cetyl alcohol, stearyl alcohol, behenyl alcohol, isostearyl alcohol, octyl dodecanol and oleyl alcohol. The higher alcohol and the surfactant in the above-mentioned detergent composition can be used at a relatively wide range of ratios. The weight ratio of the higher alcohol to the surfactant is preferably between 10:100 and 100:0.5, more preferably between 50:100 to 100:5. When it is less than 10:100, the effect provided by the higher alcohol is not sufficiently exhibited. When it is more than 100: 0.5, the conditioning effects or the feeling upon use is reduced. The surfactant of the present invention can be incorporated into compositions of toiletries and detergents, for example, hair care products such as shampoos, rinses and treatments, toiletries such as cleansing creams and massage creams body cleaning agents such as body shampoos, disinfectants, fabric softeners, kitchen detergents and detergents for general cleaning. The amount of the surfactant in the composition of the present invention can appropriately be determined depending on the use and the formulation. It is generally between 0.1% by weight and 95% by weight. Another surfactant may be jointly used in such a composition unless it impairs the effect of the present invention. Examples of other surfactants include anionic surfactants such as higher fatty acid salts, polyoxyalkyl ether sulfuric acid salts, N-acylaminocarboxylic acid salts, polyoxyethylene alkyl ether carboxylic acid salts, N-acyltaurine salts and sulfosuccinic acid surfactants; ampholytic surfactants such as alkyldimethylaminoacetic acid betaine, higher fatty acid amide propyldimethylaminoacetic acid betaine and imidazoline surfactants; nonionic surfactants such as alkyl saccharide surfactants, polyoxyethylene alkyl ether surfactants, higher fatty acid alkanolamides and amine oxides; and cationic surfactants such as alkyltrimethylammonium chlorides and N-acylarginine lower alkyl ester pyrrolidonecarboxylic acid salts. In addition to the above-mentioned surfactants, a variety of additives which are ordinarily used can be added. Examples thereof include wetting agents such as ethylene glycol, propylene glycol, 1,3-butylene glycol, glycerol and sorbitol; emulsifying agents such as glycerol monostearate and polyoxyethylene sorbitan monolaurate; hydrocarbons such as liquid paraffin, vaseline and squalane; esters such as isopropyl myristate and octyldodecyl myristate; cellulose derivatives such as hydroxyethyl cellulose, hydroxypropyl cellulose and carboxymethyl cellulose; anionic polymers- such as an acrylic acid polymer; silicon derivatives; and cationic polymers such as cationic guar gum. Further, antibiotics such as paraben derivatives, perfumes, pigments, viscosity modifiers, pearling agents, antioxidants, disinfectants, anti-inflammatory agents, UV absorbers, pH adjustors and drugs, eg crude drugs can be used as required. Examples The present invention is illustrated specifically by referring to the following Examples. However, the present invention is not limited to these Examples. Production Example 1 N-(2-hydroxy-3-dodecyloxy)propyl-L-arginine hydrochloride: L-arginine (17.4 g, 0.1 mols) was dissolved in 100 ml of water in a three-necked round flask, and 100 ml of i-propanol were added thereto. Then, 24.2 g (0.1 mols) of dodecylglycidyl ether (made by Sakamoto Yakuhin Kogyo Co., Ltd.) were added dropwise thereto over a period of 30 minutes while being heat-refluxed and stirred. Further, the mixture was stirred under reflux for 3 hours. It was identified through TLC and gas chromatography that dodecylglycidyl ether disappeared. Thereafter, the resulting mixture was neutralized with 10.1 g (0.1 mols) of 36-% hydrochloric acid. The reaction solution was concentrated under reduced pressure, and the residue was purified through silica-gel column chromatography (Kieselgel 60 made by MERCK & Co., Inc., eluent = mixture of chloroform, methanol and acetic acid at a ratio of 3:1:0.5) to give 15.0 g of N-(2-hydroxy-3-dodecyloxy)propyl-L-arginine hydrochloride (yield 36.0%). TLC (mixture of butanol, acetic acid and water at a ratio of 4:1:2) : Rf = 0.64 ESI mass spectrum: 417.5 (MH+) IR (NaCl, cm -1 ): 3177, 2955, 2920, 2853, 1692, 1628, 1468, 1397, 1377, 1215, 1116 Production Example 2 N, N-bis (2-hydroxy-3-dodecyloxy)propyl-L-arginine hydrochloride: L-arginine (17.4 g, 0.1 mols) was dissolved in 100 ml of water in a three-necked round flask, and 100 ml of i-propanol were added thereto. Then, 48.4 g (0.2 mols) of dodecylglycidyl ether were added dropwise thereto over a period of 30 minutes while being heat-refluxed and stirred. Further, the mixture was stirred under reflux for 3 hours. It was identified through TLC and gas chromatography that dodecylglycidyl ether disappeared. Thereafter, the resulting mixture was neutralized with 10.1 g (0.1 mols) of 36-% hydrochloric acid. The reaction solution was concentrated under reduced pressure, and the residue was purified through silica-gel column chromatography (Kieselgel 60, eluent = mixture of chloroform, methanol and acetic acid at a ratio of 3:1:0.5) to give 11.4 g of N,N-bis(2-hydroxy-3-dodecyloxy)propyl-L-arginine hydrochloride (yield 17.2%). TLC (mixture of butanol, acetic acid and water at a ratio of 4:1:2) : Rf = 0.72 ESI mass spectrum: 659.7 (MH+) IR (NaCl, cm -1 ): 3177, 2955, 2920, 2853, 1692, 1628, 1468, 1397, 1377, 1215, 1120 Production Example 3 N-(2-hydroxy-3-octadecyloxy)propyl-L-arginine hydrochloride: L-arginine (17.4 g, 0.1 mols) was dissolved in 100 ml of water in a three-necked round flask, and 100 ml of i-propanol were added thereto. Then, 32.6 g (0.1 mols) of octadecylglycidyl ether (made by Sakamoto Yakuhin Kogyo Co., Ltd.) were added dropwise thereto over a period of 30 minutes while being heat-refluxed and stirred. Further, the mixture was stirred under reflux for 3 hours. It was identified through TLC and gas chromatography that octadecylglycidyl ether disappeared. Thereafter, the resulting mixture was neutralized with 10.1 g (0.1 mols) of 36-% hydrochloric acid. The reaction solution was concentrated under reduced pressure, and the residue was purified through silica-gel column chromatography (Kieselgel 60, eluent = mixture of chloroform, methanol and acetic acid at a ratio of 3:1:0.5) to give 21.2 g of N-(2-hydroxy-3-octadecyloxy)propyl-L-arginine hydrochloride (yield 42.3%). TLC (mixture of butanol, acetic acid and water at a ratio of 4:1:2) : Rf = 0.64 ESI mass spectrum: 501.5 (MH+) IR (NaCl, cm -1 ): 3175, 2955, 2917, 2851, 1692, 1628, 1468, 1377, 1215, 1121 Production Example 4 N,N-bis(2-hydroxy-3-octadecyloxy)propyl-L-arginine hydrochloride: L-arginine (17.4 g, 0.1. mols) was dissolved in 100 ml of water in a three-necked round flask, and 100 ml of i-propanol were added thereto. Then, 65.2 g (0.2 mols) of octadecylglycidyl ether were added dropwise thereto over a period of 30 minutes while being heat-refluxed and stirred. Further, the mixture was stirred under reflux for 3 hours. It was identified through TLC and gas chromatography that octadecylglycidyl ether disappeared. Thereafter, the resulting mixture was neutralized with 10.1 g (0.1 mols) of 36-% hydrochloric acid. The reaction solution was concentrated under reduced pressure, and the residue was purified through silica-gel column chromatography (Kieselgel 60, eluent = mixture of chloroform, methanol and acetic acid at a ratio of 3:1:0.5) to give 10.2 g of N,N-bis(2-hydroxy-3-octadecyloxypropyl)-L-arginine hydrochloride (yield 12.3%). TLC (mixture of butanol, acetic acid and water at a ratio of 4:1:2) : Rf = 0.72 ESI mass spectrum: 827.7 (MH+) IR (NaCl, cm -1 ): 3175, 2955, 2917, 2851, 1692, 1628, 1468, 1377, 1215, 1121 Production Example 5 Nε - (2-hydroxy-3-dodecyloxy)propyl-L-lysine hydrochloride: L-lysine hydrochloride (18.3 g, 0.1 mols) and 2.0 g (0.2 mols) of sodium hydroxide were dissolved in 100 ml of water in a three-necked round flask, and 100 ml of i-propanol were added thereto. Then, 24.2 g (0.1 mols) of dodecylglycidyl ether were added dropwise thereto over a period of 30 minutes while being heat-refluxed and stirred. Further, the mixture was stirred under reflux for 3 hours. It was identified through TLC and gas chromatography that dodecylglycidyl ether disappeared. Thereafter, the resulting mixture was neutralized with 10.1 g (0.1 mols) of 36-% hydrochloric acid. The reaction solution was concentrated under reduced pressure, and the residue was purified through silica-gel column chromatography (Kieselgel 60, eluent = mixture of chloroform, methanol and acetic acid at a ratio of 3:1:0.5) to give 10.1 g of Nε- (2-hydroxy-3-dodecyloxy)propyl-L-lysine hydrochloride (yield 23.7%). TLC (mixture of butanol, acetic acid and water at a ratio of 4:1:2) : Rf = 0.42 ESI mass spectrum: 389.4 (MH+) IR (Nacl, cm -1 ): 2955, 2923, 2853, 1620, 1586, 1468, 1120 Production Example 6 L-lysine hydrochloride (18.3 g, 0.1 mols) and 2.0 g (0.2 mols) of sodium hydroxide were dissolved in 100 ml of water in a three-necked round flask, and 100 ml of i-propanol were added thereto. Then, 48.4 g (0.2 mols) of dodecylglycidyl ether were added dropwise thereto over a period of 30 minutes while being heat-refluxed and stirred. Further, the mixture was stirred under reflux for 3 hours. It was identified through TLC and gas chromatography that dodecylglycidyl ether disappeared. Thereafter, the resulting mixture was neutralized with 10.1 g (0.1 mols) of 36-% hydrochloric acid. The reaction solution was concentrated under reduced pressure, and the residue was purified throuqh silica-gel column chromatography (Kieselgel 60, eluent = mixture of chloroform, methanol and acetic acid at a ratio of 3:1:0.5) to give 30.7 g of hydrochloride of an adduct of dodecylglycidyl ether and L-lysine at a ratio of 2:1 (yield 46.1%). ESI mass spectrum: 631.6 (MH+) IR (NaCl, cm -1 ): 2955, 2923, 2853, 1619, 1574, 1468, 1410, 1122 Production Example 7 Nε-(2-hydroxy-3-octadecyloxy)propyl-L-lysine hydrochloride: L-lysine hydrochloride (18.3 g, 0.1 mols) and 2.0 g (0.2 mols) of sodium hydroxide were dissolved in 100 ml of water in a three-necked round flask, and 100 ml of i-propanol were added thereto. Then, 32.6 g (0.1 mols) of octadecylglycidyl ether were added dropwise thereto over a period of 30 minutes while being heat-refluxed and stirred. Further, the mixture was stirred under reflux for 3 hours. It was identified through TLC and gas chromatography that octadecylglycidyl ether disappeared. Thereafter, the resulting mixture was neutralized with 10.1 g (0.1 mols) of 36-% hydrochloric acid. The reaction solution was concentrated under reduced pressure, and the residue was purified through silica-gel column chromatography (Kieselgel 60, eluent = mixture of chloroform, methanol and acetic acid at a ratio of 3:1:0.5) to give 12.0 g of Nε-(2-hydroxy-3-octadecyloxy)propyl-L-lysine hydrochloride (yield 23.6%). TLC (mixture of butanol, acetic acid and water at a ratio of 4:1:2) : Rf = 0.42 ESI mass spectrum: 473.5 (MH+) IR (NaCl, cm -1 ): 2955, 2923, 2853, 1620, 1586, 1468, 1120 Production Example 8 L-lysine hydrochloride (18.3 g, 0.1 mols) and 2.0 g (0.2 mols) of sodium hydroxide were dissolved in 100 ml of water in a three-necked round flask, and 100 ml of i-propanol were added thereto. Then, 65.2 g (0.2 mols) of octadecylglycidyl ether were added dropwise thereto over a period of 30 minutes while being heat-refluxed and stirred. Further, the mixture was stirred under reflux for 3 hours. It was identified through TLC and gas chromatography that octadecylglycidyl ether disappeared. Thereafter, the resulting mixture was neutralized with 10.1 g (0.1 mols) of 36-% hydrochloric acid. The reaction solution was concentrated under reduced pressure, and the residue was purified through silica-gel column chromatography (Kieselgel 60, eluent = mixture of chloroform, methanol and acetic acid at a ratio of 3:1:0.5) to give 40.3 g of hydrochloride of an adduct of octadecylglycidyl ether and L-lysine at a ratio of 2:1 (yield 48.3%). ESI mass spectrum: 799.7 (MH+) IR (NaCl, cm -1 ) : 2955, 2923, 2853, 1619, 1574, 1468, 1410, 1122 Production Example 9 L-arginine was reacted with dodecylglycidyl ether in the same manner as in Production Example 1. After it was identified through TLC and gas chromatography that dedecylglycidyl ether disappeared, the reaction solution was neutralized with 36-% hydrochloric acid. The reaction solution was concentrated under reduced pressure to give 47.3 g of a reaction mixture. Production Example 10 L-lysine was reacted with dodecylglycidyl ether in the same manner as in Production Example 5. After it was identified through TLC and gas chromatography that dodecylglycidyl ether disappeared, the reaction solution was neutralized with 36-% hydrochloric acid. The reaction solution was concentrated under reduced pressure to give 52.1 g of a reaction mixture. Production Example 11 L-arginine (17.4 g, 0.1 mols) was dissolved in 100 ml of water in a three-necked round flask, and 100 ml of i-propanol were added thereto. Then, 25.6 g (0.1 mols) of Heroxine 8 (made by ACI Japan Ltd.) were added dropwise thereto over a period of 30 minutes while being heat-refluxed and stirred. Further, the mixture was stirred under reflux for 3 hours. After it was identified through TLC and gas chromatography that glycidyl ether disappeared, 12.9 g (0.1 mols) of DL-pyrrolidonecarboxylic acid were added thereto. Then, i-propyl alcohol was distilled off under reduced pressure, and the reaction solution was poured into cold acetone to give 50.9 g of a mixture of N-(2-hydroxy-3-dodecyloxy)propyl-L-arginine.DL-pyrrolidonecarboxylic acid salt and N-(2-hydroxy-3-tetradecyloxy) propyl-L-arginine-DL-pyrrolidonecarboxylic acid salt. The ESI mass spectrum of the resulting mixture was measured, and peaks of 417.5 (MH+) and 445.5 (MH+) were identified. Test Example 1 With respect to the surfactants obtained in Production Examples 1 and 5 and trimethylstearylammonium chloride and N-cocoyl-L-arginine ethyl ester·DL-pyrrolidonecarboxylic acid salt as comparative examples, the primary irritations of the skin and the eye mucous membrane were measured by the following test methods. The results are shown in Table 1. (1) Test for primary skin irritation Each of four New Zealand white male rabbits was seal-coated with a patch test plaster permeated with 0.3 ml of a 1-% surfactant aqueous solution, and was allowed to stand for 24 hours. Then, the plaster was removed from the rabbit. After 24 hours, the irritation was evaluated according to the following Draise's evaluation standard. Draise's evaluation score Irritation level 4 or more heavy from 2 to less than 4 light less than 2 slight (2) Test for primary eye mucous membrane irritation The lower eyelids of both eyes of each of four New Zealand white male rabbits were formed into a bag shape, and 0.1 ml of a 1-% surfactant aqueous solution were dropped therein. Thereafter, the upper and lower eyelids were gently joined. After 24 hours of the dropping, the irritation was evaluated according to the following Draise's evaluation standard. Draise's evaluation score Irritation level 50 or more heavy from 20 to less than 50 medium from 10 to less than 20 light less than 10 slight Irritation Skin Mucous membrane Examples Compound in Production Example 1 slight slight Compound in Production Example 5 slight slight Comparative Examples trimethylstearylammonium chloride heavy medium Nα-cocoyl-L-arginine ethyl ester salt slight slight From Table 1, it becomes apparent that the surfactant of the present invention gives a low level of irritation. Test Example 2 The surfactants were measured for the bubbling power and the bubble stability by the following test methods. Tests for bubbling power and bubble stability: Each of the surfactants was adjusted with purified water such that the concentration of the activator reached 0,25% by weight. Fifty grams of the aqueous solution were charged into a 350-milliliter home mixer, and stirred for 5 seconds. The volume (ml) of the bubbles immediately after the stirring and the volume (ml) of the bubbles after 5 minutes of the stirring were measured. The volume of bubbles immediately after the stirring was defined as a bubbling power, and the bubble retention calculated from the following equation was defined as a bubble stability. Bubble retention (%) = (volume of bubbles after 5 minutes of stirring / volume of bubbles immediately after stirring) x 100 Bubbling power (ml) Bubble stability (%) Examples Compound in Example 1 150 80.0 Compound in Example 5 130 69.2 Comparative Examples N-(2-hydroxy-3-dodecyloxy)propyl-methyltaurine sodium salt 80 37.5 N-(2-hydroxy-3-dodecyloxy)propyl-sarcosine sodium salt 120 58.3 Coconut oil fatty acid amide propyl betaine solution 140 64.3 N-coconut oil fatty acid-L-glutamic acid triethanolamine 130 61.5 From Table 2, it becomes apparent that the surfactant of the present invention exhibits the bubbling power which is the same as, or higher than, that of the usual surfactant which exhibits a low level of irritation. Test Example 3 The solubility of each surfactant in water was tested by the following method. Each of the surfactants was diluted with water to a concentration of 1, 3, 5, 10 or 20% by weight, and the solution was rendered uniform while being stirred at 50°C. The resulting solution was allowed to stand overnight at 25°C, and the solubility was then visually measured. The results are shown in Table 3. 1% 3% 5% 10% 20% Invention Compound in Example 1 clear clear clear clear clear Comparative Example N-(2-hydroxy-hexadecyl)-L-arginine hydrochloride slightly turbid turbid milk-white milk-white milk-white From Table 3, it becomes apparent that the compound of the present invention exhibits a higher solubility in water. Accordingly, a toiletry or detergent composition having a higher solution stability can be formed therefrom because separation or precipitation of the surfactant component can be prevented effectively. Test Example 4 A 0.5-% surfactant aqueous solution (150 g) was prepared. A hairpiece made of 20 g of the healthy hair of a Japanese woman was washed with a 1-% lauryl ether sodium sulfate aqueous solution, and then dipped in the above-mentioned aqueous solution for 1 minute. The resulting hairpiece was gently rinsed with a running hot water, and then dried using a dryer. With respect to a softness, a combing property, a moist feeling and a sticky feeling of the hair after the drying, the organoleptic evaluation was conducted by 8 expert panelists. In the evaluation, average values were calculated on the basis of the following standard. When the average value was 4.5 or more, the property was evaluated as very good (o ○). When the average value was between 3.5 and 4.4, the property was evaluated as good (○). When the average value was between 2.5 and 3.4, the property was evaluated as common (Δ). When the average value was 2.4 or less, the property was evaluated as bad. <Evaluation standard> Softness of the hair: 5: very soft and smooth 4: soft 3: common 2: slightly hard 1: hard Combing property of the hair: 5: Combing is conducted well and quite smoothly. 4: Combing is conducted well. 3: Combing property is common. 2: Combing property is slightly bad. 1: Combing property is bad, and combing is sometimes interrupted. Moist feeling: 5: quite moist 4: moist 3: common 2: slightly dry and hard 1: quite dry and hard Sticky feeling: 5: not sticky 4: little sticky 3: common 2: slightly sticky 1: sticky Example Comparative Example Compound in Production Example 1 N-(2-hydroxyhexadecyl)-L-arginine hydrochloride Untreated Softness o ○ ○ bad Combing property ○ Δ bad Moist feeling o ○ ○ bad Sticky feeling ○ ○ bad Test Example 5 A detergent composition shown in Table 5 was prepared. Each of eight expert panelists washed the hair with a commercially available shampoo, and then used the detergent composition. With respect to a softness, a combing property, a moist feeling and a sticky feeling of the air after the drying, the organoleptic evaluation was conducted by them. In the evaluation, average values were calculated on the basis of the following standard. When the average value was 4.5 or more, the property was evaluated as very good (o ○). When the average value was between 3.5 and 4.4, the property was evaluated as good (○). When the average value was between 2.5 and 3.4, the property was evaluated as common (Δ). When the average value was 2.4 or less, the property was evaluated as bad (×). <Evaluation standard> Softness of the hair: 5: very soft and smooth 4: soft 3: common 2: slightly hard 1: hard Combing property of the hair: 5: Combing is conducted well and quite smoothly. 4: Combing is conducted well. 3: Combing property is common. 2: Combing property is slightly bad. 1: Combing property is bad, and combing is sometimes interrupted. Moist feeling: 5: quite moist 4: moist 3: common 2: slightly dry and hard 1: quite dry and hard Sticky feeling: 5: not sticky 4: little sticky 3: common 2: slightly sticky 1: sticky From Tables 4 and 5, it becomes apparent that the surfactant and the detergent composition of the present invention exhibit excellent conditioning effects. Mixing Examples 1 and 2 Shampoo A composition shown in each of Tables 6 and 7 was heat-dissolved at from 70 to 80°C, and then cooled to room temperature to obtain a shampoo. This shampoo exhibited an excellent rinsing property, and a feeling after cleaning was satisfactory. Composition Amount Compound in Production Example 1 5.0 N-cocoyl-L-glutamic acid TEA 2 Polyoxyethylene (3) lauryl ether sodium sulfate 10 Lauric acid monoethanolamide 1 Propylene glycol 5 Cationic polymer ("MERQUAT 100" made by MERCK & Co., Inc.) 0.3 Antiseptic 0.1 Perfume 0.1 EDTA sodium salt 0.1 Purified water balance Composition Amount Compound in Production Example 5 1.0 Lauric acid amide propylbetaine 15 Coconut oil fatty acid diethanolamide 5 DL-pyrrolidonecarboxylic acid sodium salt 5 Ampholytic polymer ("PLAS SIZE L-401 made by GOO Chemical Co., Ltd.") 0.8 Citric acid 0.5 Antiseptic 0.1 Perfume 0.1 Purified water balance Mixing Examples 3 to 5 Rinse A composition shown in each of Tables 8 to 10 was heat-dissolved at from 70 to 80°C, and then cooled to room temperature to obtain a rinse. This rinse exhibited an excellent rinsing property, and a feeling after drying was satisfactory. Composition Amount Compound in Production Example 11 5 Polyoxyethylene (3) sulfosuccinic acid sodium salt 5 Cocoylisethionic acid sodium salt 2 Pyroglutamic acid glyceryl oleate 1 N-lauroyl-β-alanine TEA 1 Polyethylene glycol monostearate 0.5 Emorient oil ("Eldew CL-301" made by Ajinomoto Co., Inc.) 3 Wetting agent ("Prodew 100" made by Ajinomoto Co., Inc.) 5 Antiseptic 0.1 Perfume 0.1 Purified water balance Composition Amount Compound in Production Example 3 1 Isostearic acid diethanolamide 2 Cetanol 2 Liquid paraffin 1 Polyoxyethylene (5) oleyl ether 0.3 1,3-butylene glycol 5 Trimethylstearylammonium chloride 0.1 Hydroxyethyl cellulose 0.5 Antiseptic 0.1 Perfume 0.1 Purified water balance Composition Amount Compound in Production Example 5 6 Cetanol 6 Glycerol 3 Partially deacetylated chitin 0.5 Polyoxyethylene (20) sorbitan monostearate 0.2 Antiseptic 0.1 N-laurolyllysine trace Purified water balance Mixing Examples 6 and 7 Hair conditioner A composition shown in each of Tables 11 and 12 was heat-dissolved at from 70 to 80°C, and then cooled to room temperature to obtain a hair conditioner. Composition Amount Compound in Production Example 2 1 Cetanol 5 Coconut oil fatty acid diethanolamide 4 Dimethylpolysiloxane (1,000 cs) 1 Polyethylene glycol (400) 0.2 vaseline 0.5 Self-emulsifiable glycerol monostearate 0.2 Glycerol 1 Hydroxyethyl cellulose 0.8 Antiseptic 0.2 Purified water balance Composition Amount Compound in Production Example 6 5 Behenyl alcohol 7 Isopropyl myristate 1 Dipropylene glycol 3 Polyoxyethylene (4) stearyl ether 5 Polyethylene glycol dioleate 0.5 Polyethylene glycol 0.5 Sodium lactate 0.1 Antiseptic 0.1 Purified water balance Mixing Example 8 Hair lotion A composition shown in Table 13 was heat-dissolved at from 40 to 50°C, and then cooled to room temperature to obtain a hair lotion. Composition Amount Compound in Production Example 5 0.05 Oleyl alcohol 0.2 Liquid paraffin 0.5 Ethanol 5 Sorbitol 4 Polyoxyethylene (20) lauryl ether 2.5 Sorbitan monolaurate 0.5 Pigment 0.1 Perfume 0.1 Antiseptic 0.1 Purified water balance Test Example 6 A cotton towel on the market and an acrylic jersey were washed twice with a clothing detergent on the market using an electric washing machine (a double-tank type). Thereafter, they were rinsed with city water of ordinary temperature. Each of the surfactants was adjusted with city water at 25°C such that the concentration of the surfactant reached 50 ppm to obtain homogeneous solutions. The cotton towel and acrylic jersey whose weight ratio was 1:1 were soaked in the surfactant solution whose weight is 30 times as large as the weight of the cotton towel and the acrylic jersey. After 3 minutes, they were spun dry using the electric washing machine. Thereafter, they were dried at 25°C and a relative humidity of 40% for 24 hours, and were used for the evaluation. (1) Test for fabric softness. With respect to softness, the organoleptic evaluation was conducted by eight panellists. In the evaluation, average values were calculated on the basis of the following standard. <Evaluation standard> 4: equal to distearyl dimethyl ammonium chloride 3: softer than trimethyl stearyl ammonium chloride 2: equal to trimethyl stearyl ammonium chloride 1: equal to untreated (2) Test for hygroscopic property According to JIS (Japan Industrial Standard) L 1096, a cotton towel treated with each of the surfactants was cut into a rectangular fragment (20mm X 150mm), and the end part of the fragment (5mm) was soaked in water coloured by blue dye . After five minutes, the height of ascended water was measured. Surfactant Softness Hygroscopic (mm) Comparative Example Distearyl dimethyl ammonium chloride 4 25 Trimethyl stearyl ammonium chloride 2 37 Example Surfactant in Example 11 4 77 Surfactant in Example 7 4 80 Surfactant in Example 8 4 77 Surfactant in Example 10 3 77 Mixing Examples 9 and 10 Fabric Softener A composition shown in each of Tables 15 and 16 was heat-dissolved at from 70 to 80°C, and then cooled to room temperature to obtain a fabric softener. This fabric softener exhibited an excellent softening property, and a hygroscopic property of fabric treated with it was satisfactory. In conclusion, embodiments of the surfactant of the present invention have low irritability towards the skin or the mucous membrane, and give an excellent feeling upon use. Accordingly, examples of the surfactant find wide acceptance. They may be advantageously used as conditioning components or detergent components in hair toiletries such as shampoos, rinses, hair treatments and the like.

Claims: A method for producing a derivative of a basic amino acid, or a salt of said derivative, comprising heat reacting a basic amino acid or a salt thereof with a glycidyl ether in an alcohol or in a mixed solvent of an alcohol and water. A method according to claim 1 wherein the glycidyl ether has the formula (8) wherein R 11 represents a linear or branched alkyl or alkenyl group having from 8 to 22 carbon atoms and the reaction is carried out under alkaline conditions. A derivative of a basic amino acid or a salt of said derivative wherein the derivative is represented by one of the formulae (1) to (4) wherein R 1 to R 6 each represent a linear or branched alkyl or alkenyl group having from 8 to 22 carbon atoms, provided that R 2 and R 3 , or R 5 and R 6 may be the same or different, m represents an integer of from 1 to 5, and X represents any of the following substituents, or salts thereof. A basic amino-acid derivative according to claim 3 represented by formula wherein R 7 represents a linear or branched alkyl or alkenyl group having from 8 to 22 carbon atoms or a salt thereof. A basic amino-acid derivative according to claim 3 represented by formula wherein R 8 and R 9 are the same or different and each represents a linear or branched alkyl or alkenyl group having from 8 to 22 carbon atoms or a salt thereof. A basic amino-acid derivative according to claim 3 represented by formula wherein R 10 represents a linear or branched alkyl or alkenyl group having from 8 to 22 carbon atoms or a salt thereof. A toiletry or detergent composition containing a derivative or salt of any one of claims 3 to 6. A toiletry or detergent composition according to claim 7 further containing a higher alcohol. A surfactant composition comprising a derivative or salt of any one of claims 3 to 6. A surfactant composition according to claim 9 comprising an aqueous solution of the amino acid derivative or salt of any one of claims 3 to 6, the concentration of the derivative or salt in the solution being between 0.1% and 95% by weight. A fabric softener composition comprising a derivative or salt of any one of claims 3 to 6.

Inventors: HONMA MASAO, NOGUCHI YASUNOBU, SANO KEIGO, TABOHASHI TATSURO, HONMA, MASAO, NOGUCHI, YASUNOBU, SANO, KEIGO, TABOHASHI, TATSURO, Honma, Masao, c/o Center Research Lab., NOGUCHI, YASUNOBU, C/O CENTRAL RESEARCH LAB., Tabohashi, Tatsuro, c/o Central Research Lab.
Applicants: AJINOMOTO KK, AJINOMOTO CO., INC.
Application year: 1997
Main classification: B01F17
IPC codes: B01F17