Methods and compositions for protecting hair

Abstract

A method of protecting hair from damage by applying a long-chain unhydrolyzed alkyltrialkoxysilane to the hair shaft, then hydrolyzing and polymerizing the alkyltrialkoxysilane to form an impermeable outer layer on the hair shaft by utilizing pH adjusted water, followed by the application of heat. Alternatively, the alkyltrialkoxysilane may be applied to the hair in combination with an alkyl or alkenyl succinic anhydride prior to the application of heat.

Description

[Background technology]

[0001] Hair damage due to physical stress, chemical treatments, or natural aging is, of course, inevitable. Because hair does not naturally heal, damage is typically irreversible, yet most hair treatments focus on repairing already damaged hair.

[0002] The hair surface structure, the outermost layer of the hair shaft, is rich in 18-methyleicosanoic acid (18-MEA), which is covalently bound to the keratin-associated proteins of the hair cuticle, forming a relatively smooth, hydrophobic protective coating (see Non-Patent Document 1). When this layer of 18-MEA is lost, it is not replenished, and the natural structure and behavior of the hair are impaired. Concomitant with this loss, negatively charged sulfonic acid groups (SO3 - ) is exposed to the outermost surface of the hair and is the active species that makes hair relatively hydrophilic, sensitive to changes in humidity, and dull and frizzy in appearance. Loss of 18-MEA also exposes keratin-associated proteins, peptides, and amino acids, leading to their further damage and destruction.

[0003] The loss of 18-MEA from hair has traditionally been attributed to SO3 - This has been addressed with products containing positively charged quaternary salts that ionically bond with the site, temporarily neutralizing the negative charge on the hair. The main drawback to the use of these salts is that they only weakly bind to the damaged site on the hair shaft and are limited to low concentration levels. Furthermore, the combination of quaternary salts and SO3 - The ionic bond between the 18-MEA and the ionic bond is easily broken by simply washing or brushing the hair, making the effect temporary. Most products containing quaternary salts to treat 18-MEA loss incorporate fatty acids and other ingredients that cause buildup if used excessively. Therefore, most of these treatments are temporary and must be used regularly to achieve results. Furthermore, these products do not prevent further loss of 18-MEA; they only reduce the appearance of existing damage by neutralizing the charge. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] Tokunaga, Cosmetics, 6, 31 (2019) Summary of the Invention [Problem to be solved by the invention]

[0005] Another conventional approach to treating damaged hair involves penetrating the damaged hair cuticle with 18-MEA to correct the damage. For example, U.S. Patent No. 8,470,064 teaches that short-chain alkyltrialkoxysilanes of six carbons or less can penetrate the hair cuticle and improve hair manageability. Despite this benefit, structural changes occur in hair treated with these methods. U.S. Patent No. 10,487,242 describes a hair treatment method in which prehydrolyzed or prepolymerized alkyltrialkoxysilanes (alkylsilanetriols or alkylsilsesquioxanes) are applied directly to the hair or stabilized in an emulsion. However, there remains a need in the art for methods to prevent damage to the hair shaft. [Means for solving the problem]

[0006] In one aspect of the present disclosure, there is provided a method for protecting hair, comprising: (a) applying at least one long-chain alkyltriethoxysilane to wet or dry hair; (b) applying water adjusted to an acidic pH to the hair; (c) heating the hair; The present invention provides a method comprising:

[0007] In another aspect of the present disclosure, there is provided a method of protecting hair, comprising: (a) applying to wet or dry hair a mixture comprising at least one long-chain alkyltriethoxysilane and at least one long-chain alkyl or alkenyl succinic anhydride; (b) heating the hair; The present invention provides a method comprising:

[0008] In a further aspect of the present disclosure, there is provided a composition comprising at least one long chain alkyltriethoxysilane and at least one long chain alkyl or alkenyl succinic anhydride, which when applied to hair and allowed to dry forms a protective, elastic outer layer.

[0009] Advantageous refinements of the invention, which can be implemented alone or in combination, are defined in the dependent claims.

[0010] In summary, the following embodiments are proposed as being particularly preferred within the scope of the present invention.

[0011] Embodiment 1: A method for protecting hair, comprising: (a) applying at least one long-chain alkyltriethoxysilane to wet or dry hair; (b) applying water adjusted to an acidic pH to the hair; (c) heating the hair; A method comprising:

[0012] Embodiment 2: The method of embodiment 1, wherein the alkyl group of the at least one alkyltriethoxysilane contains from about 8 to about 22 carbon atoms.

[0013] Embodiment 3: The method of embodiment 1 or 2, wherein the alkyl group of the at least one alkyltriethoxysilane contains from about 12 to about 16 carbon atoms.

[0014] Embodiment 4: The method of any one of embodiments 1 to 3, wherein the water in step (b) has a pH of about 4-5.

[0015] Embodiment 5: The method of any one of embodiments 1 to 4, wherein step (c) comprises applying heat from a hair dryer, curling iron, and / or straightener.

[0016] Embodiment 6: The method of any one of embodiments 1 to 5, wherein the protected hair has a protective elastic outer layer.

[0017] Embodiment 7: The method of any one of embodiments 1 to 6, wherein the alkyltriethoxysilane hydrolyzes and polymerizes on the surface of the hair to form a protective film.

[0018] Embodiment 8: The method of any of embodiments 1 to 7, wherein step (b) comprises applying a solution of acetic acid, citric acid, or a buffer system to the hair.

[0019] Embodiment 9: The method of any one of embodiments 1 to 8, wherein step (a) comprises applying a solution containing about 5 to 60 weight percent of at least one alkyltriethoxysilane in a volatile or non-volatile solvent.

[0020] Embodiment 10: A method for protecting hair, comprising: (a) applying to wet or dry hair a mixture comprising at least one long-chain alkyltriethoxysilane and at least one long-chain alkyl or alkenyl succinic anhydride; (b) heating the hair; A method comprising:

[0021] Embodiment 11: The method of embodiment 10, wherein the alkyl group of the at least one alkyltriethoxysilane contains from about 8 to about 22 carbon atoms.

[0022] Embodiment 12: The method of embodiment 10 or 11, wherein the alkyl group of the at least one alkyltriethoxysilane contains from about 12 to about 16 carbon atoms.

[0023] Embodiment 13: The method of any of embodiments 10 to 12, wherein the alkyl or alkenyl group of the alkyl or alkenyl succinic anhydride contains from about 8 to about 18 carbon atoms.

[0024] Embodiment 14: The method of any of embodiments 10 to 13, wherein step (b) comprises applying heat from a hair dryer, curling iron, and / or straightener.

[0025] Embodiment 15: The method of any of embodiments 10 to 14, wherein the protected hair has a protective elastic outer layer.

[0026] Embodiment 16: The method of any one of embodiments 10 to 15, wherein the alkyltriethoxysilane hydrolyzes and polymerizes on the surface of the hair to form a protective film.

[0027] Embodiment 17: The method of any of embodiments 10 to 16, wherein the mixture contains at least about 0.5 wt. % and less than about 10 wt. % of at least one long-chain alkyl or alkenyl succinic anhydride, the remainder being at least one alkyltriethoxysilane.

[0028] Embodiment 18: The method of any of embodiments 10 to 17, wherein the mixture contains at least about 0.5 wt. % and less than about 10 wt. % of at least one long-chain alkyl or alkenyl succinic anhydride, and about 5 to 60 wt. % of at least one alkyltriethoxysilane.

[0029] Embodiment 19: A composition comprising at least one long chain alkyltriethoxysilane and at least one long chain alkyl or alkenyl succinic anhydride, which when applied to hair and allowed to dry forms a protective, elastic outer layer.

[0030] Embodiment 20: The composition of embodiment 19, wherein the alkyl group of the at least one alkyltriethoxysilane contains from about 8 to about 22 carbon atoms, and the alkyl or alkenyl group of the at least one alkyl or alkenyl succinic anhydride contains from about 8 to about 18 carbon atoms. DETAILED DESCRIPTION OF THE INVENTION

[0031] Aspects of the present disclosure relate to methods of protecting the hair shaft before damage, thus preserving its original structure and extending its lifespan. Such methods offer additional benefits when used on damaged or undamaged hair by providing a healthier appearance, strength, and shine.

[0032] The method described herein forms a protective, elastic, and impermeable outer layer on each hair shaft, preventing the loss of 18-MEA during chemical and physical treatments and aging, and ensuring the integrity of the hair shaft. This is achieved by applying an alkyltriethoxysilane with a sufficient number of carbon atoms to wet or dry hair so that penetration into the cuticle does not occur and the structural integrity of the hair shaft is maintained. After application, the alkyltriethoxysilane undergoes a hydrolysis and polymerization process on the outer surface of the hair shaft when the pH is changed from neutral to slightly acidic and heat is applied. An appropriate alkyl group length, i.e., from about 8 to about 22 carbon atoms, is selected so that its hydrophobic behavior is similar to that of 18-MEA and its molecular size is large enough to prevent penetration into the hair shaft. Therefore, the alkyl group can have about 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, or 22 carbon atoms. Alkyltriethoxysilanes having from about 12 to about 16 carbon atoms appear to have the best compatibility and performance and are currently preferred. Thus, preferred alkyltriethoxysilanes contain about 12, 13, 14, 15, or 16 carbon atoms. When applied to hair, hydrolyzed, and polymerized, a protective layer is formed, leaving the hair fibers individual, i.e., not connected or linked by a continuous film, but rather smooth and organized, and better able to resist mechanical challenge.

[0033] A first method for protecting hair according to the present disclosure involves applying at least one long-chain alkyltriethoxysilane directly to wet or dry hair, followed by applying water adjusted to an acidic pH, preferably about 4-5, and heating the hair. The term "long-chain alkyltriethoxysilane" can be understood to encompass triethoxysilanes in which the alkyl group carbon chain contains about 8 to about 22 carbon atoms, more preferably about 12 to about 16 carbon atoms, as previously described. The hydrophobic alkyl moiety of the alkyltriethoxysilane forms a layer through hydrophobic interactions with the hydrocarbon chain of 18-MEA. After application to hair, the alkyltriethoxysilane rapidly combines with the 18-MEA-rich outer layer, and the application of acidic water hydrolyzes the triethoxy moiety of the silane. This initiates hydrolysis of the silane, which then condenses and polymerizes upon application of heat using heating appliances commonly found in hair salons, such as hair dryers, curling irons, and / or straightening irons. Adjusting the pH of the water can be accomplished by well-known methods, such as forming a dilute solution of acetic acid, citric acid, or other acidic species, or by using a buffer system such as sodium acetate / acetic acid, and then applying such a dilute solution to the hair in a second step. Alternatively, this method may involve first wetting the hair with water adjusted to an acidic pH, preferably about 4-5, and then applying at least one long-chain alkyltriethoxysilane. However, this method requires more aggressive application to achieve uniform behavior.

[0034] A second method for protecting hair according to the present disclosure involves applying a mixture containing primarily at least one long-chain alkyltriethoxysilane and at least one long-chain alkyl or alkenyl succinic anhydride to wet or dry hair. The term "long-chain alkyl or alkenyl succinic anhydride" can be understood to include succinic anhydrides in which the carbon chain of the alkyl or alkenyl group contains from about 8 to about 18 carbon atoms, more preferably about 16 carbon atoms. Thus, the alkyl or alkenyl group may contain about 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 carbon atoms. The amount of succinic anhydride in the mixture is preferably at least about 0.5% by weight and less than about 10% by weight, more preferably less than about 2% by weight. The amount of triethoxysilane in the mixture is preferably from about 50% by weight to about 99.5% by weight. Thus, the mixture may contain only succinic anhydride and triethoxysilane (0.5% to 10% by weight succinic anhydride, with the remainder triethoxysilane), or, as previously described, may be a solution containing the two components at the desired concentration relative to the remaining water or solvent. This method eliminates the need for a separate acidic water application step, and hair may be wetted before or after application. That is, the mixture may be applied to wet or dry hair. After application of the mixture containing alkyltriethoxysilane and alkyl or alkenyl succinic anhydride, the components are further condensed by applying heat to the hair using heating appliances commonly found in hair salons.

[0035] It is also within the scope of the present disclosure to apply long-chain alkyltrialkoxysilanes to hair in combination with a known carrier or vehicle that does not hydrolyze the alkyltrialkoxysilane prior to application to the hair. For example, a formulation containing 5-60 wt. % alkyltrialkoxysilane may be mixed with a compatible non-volatile solvent, such as, but not limited to, 2-ethylhexyl palmitate or octyl trimethicone, or a volatile solvent, such as, but not limited to, propyl trimethicone or decamethylcyclopentasiloxane. Such solvents are suitable for applying the alkoxysilane alone or when mixed with succinic anhydride, so long as the components are present in solution in the desired amounts.

[0036] Hair treated by the methods disclosed herein is protected from damage (e.g., environmental, physical stress, chemical treatment, and natural aging) and maintains the behavior of "healthy" hair, including combability, shine, reduced frizz, and smooth feel. Furthermore, the impermeable outer layer formed on each hair shaft allows the protected individual hairs to move independently, yet, because they have similar physical properties, they move relatively collectively, maintaining a natural appearance and behavior. This is in stark contrast to applying polymeric materials, such as oligomeric condensation products of alkoxysilanes, to hair to create crosslinks between hair shafts. Such crosslinking does not occur in hair treated by the methods described herein.

[0037] The methods described herein are suitable for treating all types of hair, including straight, wavy, curly, or frizzy hair, untreated hair, or hair that has been bleached, colored, permed, straightened, or any other type of chemical or physical treatment, and hair of any form, shape, or length.

[0038] The invention will now be described with reference to the following non-limiting examples.

[0039] Example 1: Application of n-octyltriethoxysilane to virgin hair with acidic water and / or heat exposure Sample Preparation: Untreated hair tresses (purchased from IHIP) of curly and kinky hair (curl pattern type IV) measuring 4 inches wide and 6 inches long were washed with a common shampoo, air-dried, and cut into four 1-inch strips labeled A, B, C, and D.

[0040] Sample 1 - Hair tress A weighing 4.0 g was washed with shampoo and conditioner and allowed to air dry. This sample is referred to as the "control."

[0041] Sample 2 - Hair Strand B was sprayed with n-octyltriethoxysilane (CAS No. 2943-75-1) and thoroughly saturated. Using fingers, the material was spread throughout the tress, covering the entire surface of the hair shaft. The treated tress was exposed to air at room temperature for 10 minutes. After 10 minutes, the tress was sprayed with water adjusted to pH 4.5 with acetic acid. The tress was covered with plastic for 30 minutes and then dried using a hair dryer on high speed and heat. Once the tress was completely dry, it was combed and flattened with a 410°F straightener, using 0.5-inch sections 5-7 times. After 24 hours, the tress was washed with shampoo and conditioner and air-dried at room temperature and 67% relative humidity. The treated hair exhibited increased shine, significantly reduced frizz, increased smoothness, and facilitated dry combing.

[0042] Sample 3 - Hair Tress C was sprayed with water adjusted to pH 4.5 with acetic acid until the hair was saturated. The tress was then sprayed with enough n-octyltriethoxysilane to saturated the hair. Using fingers, the material was spread over the tress, ensuring coverage over the entire surface of the hair shaft. The tress was covered with plastic for 30 minutes, dried using a hair dryer on high speed and high heat, and then combed and flattened with a 410°F straightener in 0.5-inch sections 5-7 times. The tress was then washed with shampoo and conditioner after 24 hours and air-dried at room temperature and 67% relative humidity. The treated hair exhibited increased shine, significantly reduced frizz, increased smoothness, and facilitated dry combing.

[0043] Sample 4 - Hair Tress D was sprayed with n-octyltriethoxysilane. Using fingers, the material was spread over the tress, ensuring coverage over the entire surface of the hair shaft. The tress was covered with plastic and allowed to react for 30 minutes, then dried using a hair dryer on high speed and high heat, followed by combing and straightening with a 410°F flat iron in 0.5-inch sections 5-7 times. The tress was washed with shampoo and conditioner after 24 hours and allowed to air dry at room temperature and 67% relative humidity. The treated hair exhibited increased shine, significantly reduced frizz, increased smoothness, and facilitated dry combing.

[0044] Analysis of hair bundles A to D Hair tresses A through D were laid flat on a surface and measurements were taken at their widest area. The width measurements of the treated hair were compared to the control (A) as an indicator of frizz; the wider the tress, the more frizz there was. Trapezius A (control) was 13 cm wide. Trapezius B was 7.5 cm wide, corresponding to a 42% reduction in frizz. Trapezius C was 7.7 cm wide, corresponding to a 40% reduction in frizz. Trapezius D was 7.0 cm wide, corresponding to a 46% reduction in frizz.

[0045] Samples B, C, and D exhibited defined curl, increased shine, and increased smoothness compared to Sample A (control), and these attributes were reviewed and evaluated by individuals with expertise in the cosmetics industry. The following relationships were observed: Smoothness: C>B>D, Shine: D=C=B

[0046] SEM images were collected for samples A, B, C, and D. Samples B, C, and D showed the presence of silicone in the outer layer of the hair shaft by energy dispersive X-ray spectroscopy (EDS) analysis.

[0047] Example 2: Application of Hexadecyltriethoxysilane to Bleached Hair with Acidic Water and / or Heat Exposure Sample Preparation: Hair tresses (purchased from IHIP) measuring 4 inches wide and 6 inches long were bleached twice at level 9 bleach using a 40 volume developer. The tresses were washed with a standard shampoo, air-dried, and cut into four 1-inch strips labeled A, B, C, and D.

[0048] Sample 1 - Hair tress A was washed with shampoo and conditioner and air dried. This sample is called "Control".

[0049] Sample 2 - Hair Strand B was sprayed with hexadecyltriethoxysilane (CAS No. 16415-13-7) and thoroughly saturated. Using fingers, the material was spread over the tress, covering the entire surface of the hair shaft. The treated tress was exposed to air at room temperature for 10 minutes. After 10 minutes, water adjusted to pH 4.5 with acetic acid was sprayed onto the tress. The tress was covered with plastic and allowed to react for 30 minutes, then dried using a hair dryer on high speed and heat. Once the tress was completely dry, it was combed and flattened with a 410°F straightener, 5-7 times in 0.5-inch sections. After 24 hours, the tress was washed with shampoo and conditioner and air-dried at room temperature and 65% relative humidity. The treated hair exhibited increased shine, significantly reduced frizz, increased smoothness, and facilitated dry combing.

[0050] Sample 3 - Hair Tress C was sprayed with water adjusted to pH 4.5 with citric acid until completely saturated, and then sprayed with hexadecyltriethoxysilane in a quantity sufficient to wet the hair. Using fingers, the material was spread over the tress to cover the entire surface of the hair shaft. The tress was covered with plastic and allowed to react for 30 minutes, then dried with a hair dryer on high speed and high heat, followed by combing and straightening with a 410°F flat iron in 0.5-inch sections 5-7 times. The tress was then washed with shampoo and conditioner after 24 hours and air-dried at room temperature and 65% relative humidity. The treated hair exhibited increased shine, significantly reduced frizz, increased smoothness, and facilitated dry combing.

[0051] Sample 4 - Hair Tress D was sprayed with hexadecyltriethoxysilane (CAS No. 16415-13-7) until thoroughly saturated. Using fingers, the material was spread throughout the tress, covering the entire surface of the hair shaft. The tress was covered with plastic and allowed to react for 30 minutes, then dried using a hair dryer on high speed and high heat, followed by combing and straightening with a 410°F flat iron in 0.5-inch sections 5-7 times. The tress was washed with shampoo and conditioner after 24 hours and allowed to air dry at room temperature and 65% relative humidity. The treated hair exhibited increased shine, significantly reduced frizz, increased smoothness, and facilitated dry combing.

[0052] Analysis of hair bundles A to D Hair tresses A through D were laid flat on a surface and measurements were taken at their widest area. The width measurements of the treated hair were compared to the control as an indicator of frizz; the wider the tress, the more frizz there was. Trapezius A (control) was approximately 11 cm wide. Trapezius B was approximately 4.5 cm wide, corresponding to a 59% reduction in frizz. Trapezius C was approximately 5.0 cm wide, corresponding to a 55% reduction in frizz. Trapezius D was approximately 8.0 cm wide, corresponding to a 27% reduction in frizz.

[0053] Smoothness and shine were reviewed and evaluated by individuals with expertise in the cosmetics industry. The following relationships were observed: Samples B, C, and D showed a corrective effect compared to Sample A (control). Samples B, C, and D also showed increased shine and smoothness.

[0054] SEM images were collected for samples A, B, C, and D. Samples B, C, and D showed the presence of silicone in the outer layer of the hair shaft by energy dispersive X-ray spectroscopy (EDS) analysis.

[0055] Example 3: Application of hexadecyltriethoxysilane to hair with application of long-chain alkylsuccinic anhydride and heat exposure Sample Preparation: Untreated hair tresses (purchased from IHIP) of curly and kinky hair (curl pattern type IV) measuring 4 inches wide and 6 inches long were washed with a common shampoo, air-dried, and cut into four 1-inch strips labeled A, B, C, and D.

[0056] Sample 1 - Hair tress A weighing 4.0 g was washed with shampoo and conditioner and allowed to air dry. This sample is referred to as the "control."

[0057] Sample 2 - Hair Strand B was wetted with water and then sprayed with a solution consisting of 99% hexadecyltriethoxysilane (CAS No. 16415-13-7) and 1% dodecenyl succinic anhydride. Using fingers, the material was spread over the wet tress, covering the entire surface of the hair shaft. The tress was covered with plastic and allowed to react for 30 minutes, then dried using a hair dryer on high speed and high heat, followed by combing and straightening with a 410°F flat iron in 0.5-inch sections 5-7 times. The tress was then washed with shampoo and conditioner after 24 hours and allowed to air dry at room temperature and 67% relative humidity. The treated hair exhibited increased shine, significantly reduced frizz, increased smoothness, and facilitated dry combing.

[0058] Sample 3 - Hair Strand C was wetted with water and then sprayed with a solution consisting of 99% hexadecyltriethoxysilane (CAS No. 16415-13-7) and 1% hexadecenyl succinic anhydride. Using fingers, the material was spread over the wet tress, covering the entire surface of the hair shaft. The tress was covered with plastic and allowed to react for 30 minutes, then dried using a hair dryer on high speed and high heat, followed by combing and straightening with a 410°F flat iron in 0.5-inch sections 5-7 times. The tress was then washed with shampoo and conditioner after 24 hours and allowed to air dry at room temperature and 67% relative humidity. The treated hair exhibited increased shine, significantly reduced frizz, increased smoothness, and facilitated dry combing.

[0059] Sample 4 - Hair Strand D was wetted with water and then sprayed with a solution consisting of 99% hexadecyltriethoxysilane (CAS No. 16415-13-7) and 1% octadecenyl succinic anhydride (CAS No. 28777-98-2). Using fingers, the material was spread over the wet tress to cover the entire surface of the hair shaft. The tress was covered with plastic and allowed to react for 30 minutes. It was then dried using a hair dryer on high speed and high heat, followed by combing and ironing 0.5-inch sections 5-7 times at 410°F. The tress was then washed with shampoo and conditioner after 24 hours and allowed to air dry at room temperature and 67% relative humidity. The treated hair exhibited increased shine, significantly reduced frizz, increased smoothness, and facilitated dry combing.

[0060] Analysis of hair bundles A to D Hair tresses A through D were laid flat on a surface and measurements were taken at their widest area. The width measurements of the treated hair were compared to the control (A) as an indicator of frizz; the wider the tress, the more frizz there was. Trapeze A (control) was 13 cm wide. Trapeze B was approximately 7 cm wide, corresponding to a 46% reduction in frizz. Trapeze C was approximately 5 cm wide, corresponding to a 61.5% reduction in frizz. Sample D was approximately 5.5 cm wide, corresponding to a 57% reduction.

[0061] The smoothness and shine were reviewed and evaluated by individuals with expertise in the cosmetics industry. The following relationship was observed: Sample C showed a corrective effect compared to Sample A (control). Sample C also showed increased shine and smoothness.

[0062] Example 4: Application of Alkyltriethoxysilanes of Various Chain Lengths and Acidic Water to Hair Followed by Heat Exposure Sample Preparation: Untreated hair tresses (purchased from IHIP) of curly and kinky hair (curl pattern type IV) measuring 4 inches wide and 6 inches long were washed with a common shampoo, air-dried, and cut into four 1-inch strips labeled A, B, C, and D.

[0063] Sample 1 - Hair tress A was washed with shampoo and conditioner and air dried. This sample is called "Control".

[0064] Sample 2 - Hair Tress B was sprayed with water adjusted to pH 4.5 with citric acid until the hair was saturated, and then n-octyltriethoxysilane (CAS No. 2943-75-1) was sprayed until the tress was completely saturated. Using fingers, the material was spread over the tress, ensuring coverage over the entire surface of the hair shaft. The tress was covered with plastic and allowed to react for 30 minutes, then dried using a hair dryer on high speed and high heat, followed by combing and straightening with a 410°F flat iron in 0.5-inch sections 5-7 times. The tress was then washed with shampoo and conditioner after 24 hours and air-dried at room temperature and 67% relative humidity. The treated hair exhibited increased shine, significantly reduced frizz, increased smoothness, and facilitated dry combing.

[0065] Sample 3 - Hair Tress C was sprayed with water adjusted to pH 4.5 with citric acid until the hair was saturated, and then with isooctyltriethoxysilane until the tress was completely saturated. Using fingers, the material was spread over the tress, ensuring coverage over the entire surface of the hair shaft. The tress was covered with plastic and allowed to react for 30 minutes, then dried with a hair dryer on high speed and high heat, followed by combing and straightening with a 410°F flat iron in 0.5-inch sections 5-7 times. The tress was then washed with shampoo and conditioner after 24 hours and air-dried at room temperature and 67% relative humidity. The treated hair exhibited increased shine, significantly reduced frizz, increased smoothness, and facilitated dry combing.

[0066] Sample 4 - Hair Tress C was sprayed with water adjusted to pH 4.5 with citric acid until the hair was saturated, and then with hexadecyltriethoxysilane until the tress was completely saturated. Using fingers, the material was spread over the tress, ensuring coverage over the entire surface of the hair shaft. The tress was covered with plastic and allowed to react for 30 minutes, then dried with a hair dryer on high speed and high heat, followed by combing and straightening with a 410°F flat iron in 0.5-inch sections 5-7 times. The tress was then washed with shampoo and conditioner after 24 hours and air-dried at room temperature and 67% relative humidity. The treated hair exhibited increased shine, significantly reduced frizz, increased smoothness, and facilitated dry combing.

[0067] Analysis of hair bundles A to D Hair tresses A through D were laid flat on a surface and measurements were taken at their widest area. The width measurements of the treated hair were compared to the control as an indicator of frizz; the wider the tress, the more frizz there was. Trapezius A (control) was 12 cm wide. Trapezius B was 6.8 cm wide, corresponding to a 43% reduction in frizz. Trapezius C was 6.0 cm wide, corresponding to a 50% reduction in frizz. Trapezius D was 5.1 cm wide, corresponding to a 58% reduction in frizz.

[0068] Smoothness and shine were judged and rated by individuals with expertise in the cosmetics industry. The following relationships were observed:

[0069] Samples B, C, and D had increased shine and smoothness compared to sample A (control). Smoothness: C>D>B, Shine: D=C=B.

[0070] SEM images were collected for Samples A, B, C, and D. Samples B, C, and D showed the presence of silicone in the outer layer of the hair shaft via EDS analysis.

[0071] Those skilled in the art will appreciate that changes could be made to the embodiments described above without departing from the broad inventive concept. It is understood, therefore, that the invention is not limited to the particular embodiments disclosed, but that it is intended to cover modifications within the spirit and scope of the invention as defined by the appended claims.

Claims

1. A method for protecting hair, comprising: (a) applying at least one alkyltriethoxysilane having an alkyl group containing from 8 to 22 carbon atoms to wet or dry hair; (b) applying water adjusted to an acidic pH to the hair; (c) heating the hair; A method comprising:

2. 2. The method of claim 1, wherein the alkyl group of at least one of the alkyltriethoxysilanes contains from 12 to 16 carbon atoms.

3. 3. The method of claim 1 or 2, wherein the water in step (b) has a pH of 4 to 5.

4. 4. The method of any one of claims 1 to 3, wherein step (c) comprises applying heat from a hair dryer, curling iron, and / or straightening iron.

5. 5. The method of any one of claims 1 to 4, wherein the protected hair has a protective elastic outer layer.

6. 6. The method according to claim 1, wherein the alkyltriethoxysilane is hydrolyzed and polymerized on the surface of the hair to form a protective film.

7. 7. The method of any one of claims 1 to 6, wherein step (b) comprises applying a solution of acetic acid, citric acid, or a buffer system to the hair.

8. 8. The method of any one of claims 1 to 7, wherein step (a) comprises applying a solution containing 5 to 60% by weight of at least one alkyltriethoxysilane in a volatile or non-volatile solvent.

9. A method for protecting hair, comprising: (a) applying to wet or dry hair a mixture comprising at least one alkyltriethoxysilane having an alkyl group containing from 8 to 22 carbon atoms and at least one long chain alkyl or alkenyl succinic anhydride; (b) heating the hair; A method comprising:

10. 10. The method of claim 9, wherein the alkyl group of at least one of the alkyltriethoxysilanes contains from 12 to 16 carbon atoms.

11. 11. The process according to claim 9, wherein the alkyl or alkenyl group of the alkyl or alkenyl succinic anhydride contains from 8 to 18 carbon atoms.

12. 12. The method of any one of claims 9 to 11, wherein step (b) comprises applying heat from a hair dryer, curling iron, and / or straightening iron.

13. 13. A method according to any one of claims 9 to 12, wherein the protected hair has a protective elastic outer layer.

14. 14. The method according to any one of claims 9 to 13, wherein the alkyltriethoxysilane hydrolyzes and polymerizes on the surface of the hair to form a protective film.

15. 15. The method of any one of claims 9 to 14, wherein the mixture contains at least 0.5 wt. % and less than 10 wt. % of the at least one long chain alkyl or alkenyl succinic anhydride, the remainder being the at least one alkyltriethoxysilane.

16. 16. The method of any one of claims 9 to 15, wherein the mixture contains at least 0.5 wt. % and less than 10 wt. % of the at least one long-chain alkyl or alkenyl succinic anhydride, and 5 to 60 wt. % of the at least one alkyltriethoxysilane.

17. A composition comprising at least one alkyltriethoxysilane and at least one long chain alkyl or alkenyl succinic anhydride having an alkyl group containing from 8 to 22 carbon atoms, which when applied to hair and allowed to dry forms a protective, elastic outer layer.

18. The composition of claim 17, wherein the alkyl or alkenyl group of at least one alkyl or alkenyl succinic anhydride contains 8 to 18 carbon atoms.