Hair treatment composition

Abstract: A hair treatment composition which can imparts an excellent set-retaining power to the hair while maintaining the natural hair texture. The hair treatment composition contains a polymer capable of forming a polymer film having a water vapor transmission coefficient, which is determined on the basis of a water vapor transmission rate measured in accordance with "Testing Methods for Determination of Water Vapor Tansmission Rate of Moisture-proof Packaging Materials" [Japanese Industrial Standard (JIS) Z0208-1976], at a temperature of 20 °C under a relative humidity of 90 %, of 0.8 x 10 -3 g·m -1 ·hr -1 or below.

Description: This invention relates to the use of a polyvinyl alcohol containing a specified ionic group as a hair treatment composition which aims at retaining a hair set while maintaining the natural hair texture even under rainy weather or strong wind. With the recent diversified hair fashion, there arises great demand for hairstyling agents with various functions. Among all, it has been strongly required that a definite hair style is retained over a long period of time under various circumstances, in particular, under a high humidity or in strong winds. It has been a practice to add various polymers to hairstyling agents so as to impart a strong set-retaining power. Examples of the polymers commonly employed for such the purpose include the following ones: vinylpyrrolidone/vinyl acetate copolymer (PVP/VAE 335, manufactured by ISP); vinylpyrrolidone/dimethyl aminoethyl methacrylate copolymer (Copolymer 845, manufactured by ISP); methyl vinyl ether/monoalkyl maleate copolymer (Gantrez ES225, manufactured by ISP); and chitosan/dl-pyrrolidonecarboxylate (Kytamer PC, manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.). Each of these polymers has a high modulus of film elasticity of 1 x 10 8 Pa or more (20 °C, relative humidity 65 %). However, when the hair is set with a hairstyling agent containing such a polymer capable of forming a highly elastic film, there arise some problems. That is, the hair becomes stiff and the hairstyle loses natural feel both in appearance and texture. EP 0 141 269 A2 describes modified polyvinyl alcohol polymers containing oxylinked pendant quaternary ammonium or tertiary amine groups that are applied to skin as conditioning lotions or ointments in cosmetic and pharmaceutical formulations. According to two examples,. the modifying group is represented by -COCH 2 N + (CH 3 ) 2 (CH 2 Ph)Cl. JP-A-63035511 describes a pack cosmetic that is applied to the skin and contains a first agent comprising an aqueous solution of a carboxy-modified polyvinyl alcohol and a specific metal alt and a second agent comprising an aqueous solution of a specific alginic acid salt and borax, An object of the present invention is to solve the above-mentioned problems encountering in the prior art from a viewpoint different from the modulus of film elasticity of setting polymers (i.e., without forming any highly elastic film on the hair) by providing a hair treatment composition which can impart an excellent set-retaining power to the hair and protects the hairstyle from rainy or windy weather, while sustaining the natural hair texture. The present inventors have found out that the water content of the hair varies depending on the environmental humidity but the hair-set is deformed depending not merely on the environmental humidity but largely on the transmission rate of water which is determined on the difference between the water content of the hair and the environmental humidity; and that the hair-set can be efficaciously protected from deformation by regulating the transmission rate of water into the hair. Accordingly, the present invention provides the use for a hair treatment composition of an ionic group containing polyvinyl alcohol containing a polymer capable of forming a polymer film having a water vapor transmission coefficient, which is determined on the basis of a water vapor transmission rate measured in accordance with "Testing Methods for Determination of the Water Vapor Transmission Rate of Moisture-proof Packaging Materials" [Japanese Industrial Standard (JIS) Z0208-1976], at a temperature of 20 °C under a relative humidity of 90 %, of 0.8 x 10 -3 g·m -1 ·hr -1 or less. According to the hair treatment composition a film with a low water vapor transmission rate is formed on the hair. Therefore, even when the hair is under highly humid conditions (for example, rain), the transmission rate of the water into the hair can be suppresed at a low level. On the other hand, a hair-set is deformed at a rate largely depending on the transmission rate of water into the hair. Namely, the higher transmission rate causes the more deformation. Therefore, the hair treatment composition using said specific polymer makes it possible to considerably prevent the hair-set from deformation. In the hair treatment composition furthermore, the modulus of elasticity of the hair is not unnecessarily elevated in order to prevent the hair-set from deformation. As a result, it becomes possible to impart a natural feel to the hair-set. Fig. 1 illustrates the method for evaluating the water vapor transmission of a polymer film. Fig. 2. illustrates the method for measuring the setting efficiency. The symbols have each the following meaning. 1: Cup 2: Desiccant 3: Polymer 4: Sealing wax 5: Glove box 6: Fixation face 7: Acrylic sheet 8: Plate tress 9: Hair 10: Glass rod. As described above, the hair treatment composition is characterized by comprising a polymer having a water vapor transmission rate represented by a water vapor transmission coefficient of the polymer film not exceeding a definite level so as to improve the set-retaining power. As the polymer to be used in the hair treatment composition for improving the set-retaining power, use is made of a modified polyvinyl alcohol containing polymer having a regulated water vapor transmission rate of the polymer film, namely, one having a water vapor transmission coefficient of the polymer film, which is determined on the basis of a water vapor transmission rate measured in accordance with "Testing Methods for Determination of the Water Vapor Transmission Rate of Moisture-proof Packaging Materials" [JIS-Z0208-1976], at a temperature of 20 °C under a relative humidity of 90 %, of 0.8 x 10 -3 g·m -1 ·hr -1 or less, still preferably 0.6 x 10 -3 g·m -1 ·hr -1 or below. The term "water vapor transmission rate" as used herein means the amount (g·m -2 ·hr -1 ) of water vapor transmission through a unit area of a polymer film within a definite time. A larger water vapor transmission rate means that water vapor can the more easily transmit through the film. However, the water vapor transmission rate varies between films depending on the film thickness, even though these film are made of the same material. Thus water vapor transmission rate cannot be employed as an indication for the' comparison between the water vapor transmission rates of films differing in thickness and material from each other. In the present invention, therefore, "water vapor transmission coefficient" is used as a value showing the water vapor transmission rate of a material. "Water vapor transmission coefficient" is the slope (g·m -1 ·hr -1 ) of a line obtained by plotting the water vapor transmission rate against the reciprocal of the thickness. A larger water vapor transmission coefficient means that water vapor can the more easily transmit through the film. The water vapor transmission coefficient of a polymer film is obtained on the basis of a water vapor transmission rate measured in accordance with "Testing Methods for Determination of the Water Vapor Transmission Rate of Moisture-proof Packaging Materials" [JIS-Z0208-1976] in the following manner. Namely, as shown in Fig. 1 (a), 5 g of calcium chloride is introduced as a desiccant 2 into a cup 1 having an effective transmission sectional area of 28.27 cm 2 . Then the cup 1 is coated with a polymer film 3 and sealed by using white bees wax pellets as a sealing wax 4. The polymer film 3 employed in this case is one formed by casting a polymer solution onto a Petri dish made of Teflon and drying under reduced pressure (i.e., a cast method) and having a thickness of from 0.1 to 0.03 mm. As shown in Fig. 1 (b), the cup coated with the polymer film 3 is allowed to stand in a glove box 5 (temperature: 20 ± 0.1 °C, humidity: 90 ± 2 %). The humidity in this glove box 5 is controlled by using an aqueous solution of a compound which is commonly used for controlling humidity (i.e., phosphoric acid or glycerol). Then the cup 1 coated with the polymer film 3 is weighed with the passage of time. After the cup 1 is allowed to stand for 20 hours so as to attain the stationary state, it is weighed at intervals of 1.5 hours. When the cup 1 is allowed to stand in the glove box 5, namely, the weight of the cup is increased during the first several hours due to both of the water vapor transmission through the polymer film 3 and the moisture adsorbed by the polymer film 3 per se. After 20 hours, however, the weight of the cup 1 is changed exclusively by the water vapor transmission through the polymer film 3. Therefore, the cup is weighed at definite intervals (1.5 hours) after allowing to stand for 20 hours. As shown in Fig. 1 (c), the weight gain is plotted against time and the water vapor transmission rate J (g·m -2 ·hr -1 ) of the polymer film 3 of the corresponding thickness is determined from the slope of the line thus obtained. Next, polymer films differing in thickness from each other are also evaluated in the same manner and the water vapor transmission rate J of each polymer film is determined. As shown in Fig. 1 (d), the water vapor transmission rate is plotted against the reciprocal of film thickness and thus the water vapor transmission coefficient P (g·m -1 ·hr -1 ) is determined from the slope of the line thus obtained. Fig. 1 (c) shows an example with the use of organosiloxane (organosiloxane A-2 described in EP-A-640643 corresponding to JP-A-7-133352; the term "JP-A" as used herein means an "unexamined published Japanese patent application") films having a thickness of 0.036 mm and 0.601 mm as the polymer film. Fig. 1 (d) shows another example with the use of poly(dimethyldiallylammonium chloride) (Merquat 100: manufactured by Calgon), polyethyloxazoline (molecular weight: 50,000) and polyvinyl alcohol (PA24, manufactured by Shin-Etsu Chemical Co., Ltd.) as the polymer film. In the present invention, use is made of a polyvinyl alcohol containing polymer capable of thus forming a polymer film with a water vapor transmission coefficient of 0.8 x 10 -3 g·m -1 ·hr -1 or less. Thus, the water vapor transmission rate of water into the hair can be sufficiently controlled in the process of the absorption of water by the hair, which makes it possible to retain the hair-set for a prolonged period of time. Use of the ionic group-modified polyvinyl alcohol containing polymer makes it possible not only to regulate the water vapor transmission coefficient of the polymer film at a low level but also to improve the adhesion of the film to the hair. In addition, flaking can be prevented and further a soft touch can be imparted to the hair thereby. In this case, the effects of the modification can be achieved even though the polymer has been modified by the ionic group only at a low ratio. On the other hand, excessive modification is not preferable, since it would cause an increase in the water vapor transmission coefficient of the polymer film. Accordingly, it is preferable that the ratio of the monomers containing the ionic group is not more than 50 % by mol based on the total monomers. Such the polymer containing an ionic group and capable of forming a polymer film with a low water vapor transmission coefficient can be obtained as a copolymer of vinyl alcohol with a monomer containing the ionic group. Examples of the ionic group include carboxylic acid, such as acrylic acid, methacrylic acid, maleic acid or itaconic acid, and methacryloylaminopropyltrimethylammonium chloride, It is preferable that the polymer to be used is one having a degree of polymerization of at least 500. It is not preferable that the degree of polymerization is excessively low, since such the polymer is liable to be plasticized under a high humidity so as to lower the set-retaining power. Further, the polymer to be used in the present invention is one capable of forming a polymer film which has a modulus of elasticity (20 °C, relative humidity 65 %) ranging from 0.01 x 10 7 Pa to 7 x 10 7 Pa, preferably from 0.01 x 10 7 Pa to 5 x 10 7 Pa. It has been a practice to use a polymer having a high modulus of film elasticity in order to strengthen the set-retaining power of a hair treatment. In the present invention, however, it is not necessary to elevate the modulus of film elasticity in order to strengthen the set-retaining power, since the set-retaining power has been improved by controlling the water vapor transmission coefficient of the film as described above. In addition, a high modulus of film elasticity makes the hair stiff and deteriorates the natural feel of the styled hair. Therefore, in the present invention a polymer forming a film with a relatively low modulus of elasticity of not more than 7 x 10 7 , preferably, not more than 5 x 10 7 is used. When the modulus of film elasticity is excessively low, on the other hand, the polymer film is too soft for sustaining the hairstyle, even though the polymer can form a film having a very low water vapor transmission coefficient. Accordingly, in the present invention a polymer capable of forming a polymer film with a modulus of film elasticity falling within the range as defined above is used. In the hair treatment composition use can be made of either one of the polymers capable of forming a polymer film with a low water vapor transmission coefficient or a combination of two or more of the same. Alternatively, it is possible to use a combination of polymers which do not satisfy the above-mentioned requirements. In this a case, it is preferable to blend these polymers in such a manner as to give a polymer composition satisfying the requirements of the present invention. In the hair treatment composition invention, it is preferable that the content of the polymer component is at least 0.1 % by weight of the stock solution of the composition. In general, the upper limit of the content thereof is about 80 % by weight. If necessary, the hair treatment composition may further contain various components. For example, it may contain polymers (e.g., polyethylene glycol or polymeric silicone ), oils (hydrocarbon oil, ester oil or silicone oil ) or fats. Further, it may contain solvents, anionic, cationic or nonionic surfactants, higher alcohols, in order to solubilize or emulsify the hair treatment composition. Furthermore, it may contain various additives commonly employed in cosmetics (thickener, chelating agent, pearling agent, perfume, coloring matter, UV absorber, foaming agent or propellant, ), if needed. The hair treatment composition may be processed into various forms (hair foam, hair spray, hair set mist, hair set gel, color lotion, set lotion or blow lotion, ) without restriction. EXAMPLES To further illustrate the present invention in greater detail, the following Examples will be given. Examples 1 to 3, Comparative Examples 1 to 4 A set lotion was prepared by mixing the components as shown in Table 1 with the use of each polymer as listed in Table 2 as the polymer components. (Composition 1) Component wt. % Polymer 2 Ethanol 49 Purified water 49 The water vapor transmission coefficient and modulus of film elasticity (20 °C, 65 %) of each polymer employed were determined. As described above, the water vapor transmission coefficient was determined by forming a film by the cast method and measuring its water vapor transmission tate in accordance with JIS-Z0208-1976 at a temperature of 20 °C under a relative humidity of 90 %. The modulus of film elasticity was determined by using the film formed by the cast method similar to the determination of the water vapor transmission coefficient as a sample (30 mm in length, 5 mm in width, 0.3 mm in thickness). The measurement was performed by using a universal tensile compression tester ("Model TCM-20S", manufactured by Shinko Tsushin Kogyo) at 20 °C under a relative humidity of 65 % at a crosshead speed of 20 mm/min. The results are shown in Table 2 below. [Evaluation] The set lotions of the above Examples and Comparative Examples were evaluated in (i) set-retaining power in moist state; (ii) flaking; and (iii) softness; each in the following manner. (i) Set-retaining power in moist state As show in Fig. 2 (a), one end of hair 9 (a virgin hair bundle of a Japanese female, 10 cm in length, 1 g) was sandwiched between two acrylic plates and fixed with an adhesive, while another end was made free so as to prepare a plate tress 8. Next, the plate tress 8 was immersed in deionized water for 5 minutes and then the moisture was sufficiently eliminated with towel. Then each of the set lotions of Examples and Comparative Examples was applied onto the hair 9 of the plate tress 8 at a bathing ratio (hair : set lotion) of 1 : 0.2. As shown in Fig. 2 (b), the hair 9 was wound around a glass rod 10 (4 cm in diameter) and allowed to stand at 20 °C under a relative humidity of 65 % for 24 hours. Subsequently, the hair 9 was taken off from the glass rod 10 so as to relieve the set, as shown in Fig. 2 (c). The plate tress was fixed to the fixation face 6 with the use of a double coated tape and hung. After allowing to stand at 20 °C under a relative humidity of 98 % for 3 hours, the distance L1 between the tip of the hair 9 and the fixation face 6 was measured, as shown in Fig. 2 (d). From this length L1 and the spontaneous length L∞ of the plate tress which had been preliminarily measured in the state shown in Fig. 2 (e), the setting efficiency (%) was calculated in accordance with the following formula: Set efficiency (%) = [(L∞ - L1)/L∞] x 100. Based on the set efficiency 3 hours after relieving the set thus determined, the set-retaining power in the moist state was evaluated in 3 grades as specified below. 70 % or more : Good (G). 50 % to less than 70 %: Fair (F). less than 50 % : Bad (B). (ii) Flaking A sheet tress (a virgin hair bundle of a Japans female, 10 cm in length, 1 g) was prepared in the same manner as described above. Then each of the set lotions of Examples and Comparative Examples was applied onto the hair of the plate tress at a bathing ratio (hair : set lotion) of 1 : 0.2. After spontaneously drying, the plate tress was combed 5 times and then flaking was evaluated with the naked eye by skilled panelists in 4 grades as specified below. No or scarcely conspicuous flaking Excellent (E). Somewhat flaking but not conspicuous Good (G). Somewhat conspicuous flaking Fair (F). Conspicuous flaking Bad (B). (iii) Softness A sheet tress (a virgin hair bundle of a Japans female, 10 cm in length, 1 g) was prepared in the same manner as described above. Then each of the set lotions of Examples and Comparative Examples was applied onto the hair of the plate tress at a bathing ratio (hair : set lotion) of 1 : 0.2. After spontaneously drying, the softness of the plate tress was evaluated by touching by skilled panelists in 4 grades as specified below. Soft Excellent (E). Somewhat soft Good (G). Moderate Fair (F). Hard Bad (B). Ex. no. Set-retaining power in moist state Flaking Softness Ex. 1 G E E Ex. 2 G E E Ex. 3 G E E C. Ex. 1 B B G C. Ex. 2 B B B C. Ex. 3 B F B C. Ex. 4 B G B As is apparent from the results in Table 3, the set lotions of Examples, each containing a polymer capable of forming a polymer film with a water vapor transmission coefficient of 0.8 x 10 -3 g·m -1 ·hr -1 or less, make it possible to achieve a good set-retaining power and to impart a soft texture. Example 4 A hair set foam stock solution of the composition 2 as specified in Table 4 was prepared by mixing the components. (Composition 2: stock solution) Component wt. % Anionized polyvinyl alcohol ("HL12E", manufactured by Kuraray) 3 N-coconut oil fatty acid acyl-L-glutamic acid triethanolamine ("Amisoft CT12", manufactured by Ajinomoto) 0.3 Propylene glycol 0.1 α-Monoisostearyl glyceryl ether 0.1 8-Acetyl sucrose-modified alcohol 10.0 Perfume trace Deionized water the balance The stock solution thus obtained was mixed with liquefied petroleum gas employed as a propellant at a ratio of stock solution : propellant = 85 : 15 to thereby give a hair set foam. This hair set foam was evaluated in (i) set-retaining power in moist state; (ii) flaking; and (iii) softness; each in the same manner as described in Example 1. As a result, it showed a setting efficiency of 75 %, which indicated that it had a good set-retaining power. The flaking and softness were both evaluated as E (excellent). Example 5 A hair set spray stock solution of the composition 3 as specified in Table 5 was prepared by mixing the components. (Composition 3: stock solution) Component wt. % Anionized polyvinyl alcohol (HL12E manufactured by Kuraray) 2 α-Monoisostearyl glyceryl ether 0.1 Squalane 0.2 Propylene glycol 0.5 Deionized water 20.0 Perfume trace 8-Acetyl sucrose modified alcohol the balance The stock solution thus obtained was mixed with liquefied petroleum gas employed as a propellant at a ratio of stock solution : propellant = 50 : 50 to thereby give a hair set spray. This hair set spray was evaluated in (i) set-retaining power in moist state; (ii) flaking; and (iii) softness; each in the same manner as described in Example 1. As a result, it showed a setting efficiency of 77 %, which indicated that it had a good set-retaining power. The flaking and softness were both evaluated as E (excellent). Example 6 A hair set gel of the composition 4 as specified in Table 6 was prepared by mixing the components. (Composition 4: stock solution) Component wt. % Anionized polyvinyl alcohol (M115 manufactured by Kuraray) [water vapor transmission coefficient: 0.11 x 10 -3 g·m -1 ·hr -1 modulus of film elasticity: 7.0 x 10 7 Pa] 0.5 Anionized polyvinyl alcohol ("HL12E", manufactured by Kuraray) 3 Carboxyvinyl polymer 1.0 Triethanolamine (89 %) 1.2 α-Monoisostearyl glyceryl ether 0.1 Propylene glycol 1.0 Methyl p-hydroxybenzoate 0.2 Perfume trace Deionized water the balance The stock solution and the hair gel thus obtained were evaluated in (i) set-retaining power in moist state; (ii) flaking; and (iii) softness; each in the same manner as described in Example 1. As a result, it showed a setting efficiency of 80 %, which indicated that it had a good set-retaining power. The flaking and softness were both evaluated as E (excellent). According to the hair treatment composition of the present invention, an excellent set-retaining power can be imparted to the hair while maintaining the natural texture of the hair.

Claims: Use of an ionic group containing polymer containing polyvinyl alcohol wherein the ionic group is selected from carboxylic acid and methacryloylaminopropyltrimethylammonium chloride, and wherein said polymer is capable of forming a polymer film having a water vapor transmission coefficient, at a temperature of 20 °C under a relative humidity of 90 %, of 0.8 x 10 -3 g·m -1 ·hr -1 or below wherein said polymer film has a modulus of film elasticity at 20°C and a relative humidity of 65% in the range of from 0.01 x 10 7 Pa to 7 x 10 7 Pa, for a hair treatment composition. Use as claimed in Claim 1, wherein the ratio of a monomer containing an ionic group to the total monomers constituting the polymer is 50 % by mol or below. Use as claimed in Claim 1 or 2, wherein said polymer has a degree of polymerisation of at least 500. Use as claimed in any one of the Claims 1 to 3, wherein the polymer film has a modulus of elasticity ranging from 0.01 x 10 7 Pa to 5 x 10 7 Pa. Use as claimed in any one of the Claims 1 to 4, wherein the polymer is a random copolymer of vinyl alcohol and itaconic acid.

Inventors: HIRANO YUJI, KURE NAOHISA, HIRANO, YUJI, KURE, NAOHISA, Hirano, Yuji, c/o Kao Corp., Research Lab., Kure, Naohisa, c/o Kao Corp., Research Lab.
Applicants: KAO CORP, KAO CORPORATION
Application year: 1996
Main classification: A61K7
IPC codes: A61K8, A61Q5