Hair conditioning composition for treatment of damaged hair

Abstract

The present invention relates to a hair conditioning composition designed for the treatment of damaged hair, particularly hair subjected to chemical treatments such as coloring, bleaching, perming, and straightening. The composition includes a combination of Alpha-lipoic acid (or its derivatives) and an amidoamine, such as Stearamidopropyl dimethylamine, in a specific molar ratio. These ingredients form a stable complex in a solvent, preferably propylene glycol, which facilitates even distribution of the active components on the hair. This composition provides an effective solution for restoring and maintaining the health of hair subjected to harsh chemical treatments.

Description

[0001] HAIR CONDITIONING COMPOSITION FOR TREATMENT OF DAMAGED HAIR FIELD OF THE INVENTION

[0002] The present invention pertains to development of hair damage repair composition and method for preparation thereof. The present invention specifically relates to a hair conditioning spray formulated to prevent hair damage, especially after chemical treatments.

[0003] BACKGROUND OF THE INVENTION

[0004] Hair is a delicate structure composed of keratin fibers, which are protected by the outermost layer known as the cuticle. The cuticle acts as a barrier, providing protection against environmental factors and preserving the hair's moisture balance. However, chemical treatments, such as hair coloring, bleaching, perming, and straightening, can cause significant damage to the cuticular layer. These treatments often involve harsh chemicals that alter the hair's natural structure, leading to the breakdown of the cuticle, increased porosity, and a loss of smoothness and shine.

[0005] For example, in hair coloring and bleaching processes, oxidative agents are used to break down natural pigments and lighten the hair. This oxidative process can weaken the cuticle, causing it to lift and become more vulnerable to environmental damage, resulting in hair that appears dry, brittle, and frizzy. Similarly, in hair styling treatments like perming and straightening, chemicals used in the reduction and reformation of the hair's disulfide bonds can damage the cuticular layers, leaving the hair more prone to mechanical stress and breakage.

[0006] Moreover, repeated exposure to these chemical treatments exacerbates the damage, leading to long-term weakening of the hair structure. As the cuticle becomes compromised, it can no longer effectively protect the inner cortex of the hair, leading to further dehydration, loss of elasticity, and increased susceptibility to breakage.Currently, hair care products are available to treat and repair chemically damaged hair, but many of them do not specifically target the cuticular layer or fail to offer long-lasting protection against ongoing damage. Most conventional formulations provide only superficial conditioning and do not effectively bind to the cuticle to restore its structure or reinforce its protective barrier.

[0007] As a result, there is a clear need for a more advanced and efficacious composition that not only helps to mitigate the damage caused by chemical treatments but also actively binds to the cuticular layer, replenishing and reinforcing its integrity. This would reduce the long-term effects of damage and improve the overall health, texture, and manageability of hair post-treatment.

[0008] Thus, there is a need for an efficacious composition that binds to the cuticular layer of the hair and reduces damage following chemical treatments. Therefore, an effective solution is required that can protect, restore, and improve the condition of the hair after it has undergone chemical processing.

[0009] T. Doering, et al in International Journal of Cosmetic Science (IFSCC), 10 (2007) (4) 323-329 reported use of hydrogen peroxide for oxidation hair coloring or bleaching, which easily penetrates into the hair fiber, resulting in irreversible cleavage of cystine crosslinks. In order to mitigate the effect various classes of antioxidants were screened for their anti-hair damage effect in a permanent hair dye formulation. The screening criteria were fulfdled by organic disulfides such as a-lipoic acid (ALA). Alpha lipoic acid significantly protected human hair during oxidation coloring as demonstrated by (i) amino acid and protein analysis, (ii) surface polarity measurement, (iii) lipid analysis, (iv) differential scanning calorimetry, and (v) combing work measurement. The presence of disulfide bonds appeared to be very favorable and the intramolecular cross-link within a-lipoic acid provided a kinetically controlled protection for cysteine crosslinks during oxidation coloring.US20230285309 discloses a capsule formulation, comprising a core encapsulated in a shell layer, said core comprises a fluid material like a cream, lotion, gel, serum, cleanser, soap, shampoo, oil or clay that comprises a cosmetic, pharmaceutical, nutritious or organoleptic active compound liquid containing an active compound, said fluid material is an emulsion and may contain alpha lipoic acid as an active compound. The document however, does not disclose any example of hair care formulation containing alpha lipoic acid.

[0010] Despite its remarkable antioxidant properties, ALA is hindered by challenges such as low bioavailability, poor solubility in water, chemical instability, short half-life, and unpleasant odor. The poor solubility of ALA in water creates difficulty in formulating water-based products like shampoos and conditioners. Additionally, its poor solubility leads to uneven distribution of the active ingredient and affect its bioavailability. ALA is unstable and prone to polymerization at low pH levels. Since many hair care products are slightly acidic, this presents a significant challenge for formulators. Creating a stable formula requires careful pH control and stabilization techniques.

[0011] Additionally there are various cationic surfactants, for example, Amidoamines functionalized surfactant, which is widely used in hair care formulations. It interacts with the hair's surface, provide conditioning and protection against chemically induced damage. However, similar to alpha lipoic acid, such surfactants have poor solubility in water, and which prevents its application in water based formulation. Incorporation of such potential hair protective agents in hair care formulations gets limited due to their insolubility in water, or requires number of additional agents for stabilizing the formulations, which further increases the cost of productions of the formulations.

[0012] Thus, there is need for providing a solution, which allows cost effective and easy incorporation of alpha lipoic acid and cationic surfactant into regular hair careroutines, ensuring that the hair maintains its integrity and beauty even after frequent chemical processing.

[0013] OBJECTS OF THE INVENTION

[0014] The primary object of the present invention is to offer a formulation that binds to the cuticular layer of the hair, forming a protective barrier that helps reduce structural damage caused by harsh chemicals during and after chemical treatments. A further object of the invention is to improve the overall condition of the hair by enhancing moisture retention, restoring smoothness, and reducing frizz, thereby making the hair more manageable and healthy-looking.

[0015] An additional object of the invention is to provide a safe and effective solution that can be easily incorporated into regular hair care routines, ensuring that the hair maintains its integrity and beauty even after frequent chemical processing.

[0016] Still another object of the invention is to create a versatile product that can be used as a leave-on conditioning spray or in combination with other hair care treatments such as shampoos, hair oils, and rinse-off conditioners, offering flexibility in its application.

[0017] Another object of the invention is to provide a hair conditioning spray that effectively prevents and minimizes damage to the hair, particularly following chemical treatments such as coloring, bleaching, perming, and straightening.

[0018] Yet another object of the invention is to provide a complex containing alpha-lipoic acid and / or its derivatives and cationic surfactants, which work synergistically to protect and strengthen the hair’s cuticular layer.

[0019] SUMMARY OF THE INVENTION

[0020] In an aspect of the present invention there is provide a hair damage repair composition which comprises an aqueous solution of an antioxidant complex as ahair protective agent, wherein the antioxidant complex comprises amidoamine functionalized surfactant and alpha-lipoic acid.

[0021] It is further an aspect of the present invention to provide a water soluble antioxidant complex for hair damage repair composition, which comprises amidoamine functionalized surfactant and alpha-lipoic acid at a ratio 1:1 and 1:2 in an organic solvent.

[0022] It is also an aspect of the present invention to provide a water soluble antioxidant complex for hair damage repair composition comprising stearamidopropyl dimethylamine and alpha-lipoic acid at a ratio 1 : 1 in propylene glycol.

[0023] It is yet an aspect of the present invention to provide a water soluble antioxidant complex for hair damage repair composition comprising stearamidopropyl dimethylamine and alpha-lipoic acid at a ratio 1:2 in propylene glycol.

[0024] It is another aspect of the present invention to provide a hair spray composition comprising an aqueous solution of stearamidopropyl dimethylamine alpha-lipoate complex at a weight percentage ranging from 0.05% to 1% as an active agent, along with additional formulation excipients.

[0025] It is another aspect of the present invention to provide a hair shampoo composition comprising an aqueous solution of stearamidopropyl dimethylamine alpha-lipoate complex at a weight percentage ranging from 0.05% to 1% as an active agent, along with additional formulation excipients.

[0026] It is another aspect of the present invention to provide a hair conditioner comprising an aqueous solution of stearamidopropyl dimethylamine alpha-lipoate complex at a weight percentage ranging from 0.05% to 1% as an active agent, along with additional formulation excipients.It is another aspect of the present invention to provide a hair mask composition comprising an aqueous solution of stearamidopropyl dimethylamine alpha-lipoate complex at a weight percentage ranging from 0.05% to 1% as an active agent, along with additional formulation excipients.

[0027] It is also an aspect of the present invention to provide a method for preparation of a hair damage repair composition as claimed in preceding claim, comprising steps of:

[0028] i. preparing an antioxidant complex in water solubilized form, and

[0029] ii. combining with formulation excipient.

[0030] BRIEF DISCRIPTION OF THE FIGURES

[0031] Figure 1 illustrates A. insoluble Stearamidopropyl dimethylamine in propylene glycol solvent, B. insoluble Stearamidopropyl dimethylamine in water, C. insoluble alpha-lipoic acid in water, D. soluble alpha-lipoic acid in propylene glycol, E. Soluble StearamidopropylDimethylamine Lipoate in propylene glycol and F. Soluble Stearamidopropyl Dimethylamine Lipoate in water.

[0032] Figure 2 illustratesrH NMR spectrum of a-lipoic acid.

[0033] Figure 3 illustratesrH NMR spectrum of stearamidopropyldimethylamine.

[0034] Figure 4 illustratesrH NMR spectrum of stearamidopropyldimethylamine-a-lipoate complex.

[0035] Figure 5 illustrates FTIR spectrum of Alphalipoic Acid.

[0036] Figure 6 illustrates FTIR spectrum of Stearamidopropyldimethylamine.

[0037] Figure 7 illustrates FTIR spectrum of Stearamidopropyldimethylamine-Alpha lipoate Salt

[0038] Figure 8 illustrates the SEM image of A. damaged hair, B. StearamidopropylDimethylamine Lipoate treated hair.

[0039] DESCRIPTION OF THE INVENTION

[0040] The present invention is directed to the development of a hair damage repair composition designed to reduce the adverse effects of chemical treatments on hair.The present invention is described with reference to specific embodiments and the figures / tables including the best mode contemplated by the inventors for carrying out the invention. This description is not meant to be construed in a limiting sense, as various alternate embodiments of the invention will become apparent to persons skilled in the art, upon reference to the description of the invention. It is therefore contemplated that such alternative embodiments form part of the present invention. Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Further, unless otherwise required by context, singular terms shall include pluralities and plural terms shall include the singular. Generally, nomenclatures utilized in connection with, and techniques of, phage, bacteriophage, pH, and temperature described herein are those well-known and commonly used in the art. Some of the terms are defined briefly here below; the definitions should not be construed in a limiting sense.

[0041] The use of “comprise”, “comprises”, “comprising”, “contain”, “contains”, “containing”, “include”, “includes”, and “including” are not intended to be limiting. It is to be understood that both the foregoing general description and this detailed description are exemplary and explanatory only and are not restrictive.

[0042] In an embodiment there is provided a hair damage repair composition comprising a hair protective agent.

[0043] The present invention provides a hair damage repair composition, comprising an aqueous solution of an anti-oxidant complex as a hair protective agent.

[0044] The anti-oxidant complex comprises alpha lipoic acid or its derivative and a cationic surfactant.

[0045] The cationic surfactant of the anti-oxidant complex is an amidoamine-functionalized surfactant.The present invention provides a complex of alpha lipoic acid or its derivative with a cationic surfactant, wherein the cationic surfactant is an amido amine -functionalized surfactant.

[0046] The exemplary amidoamine functionalized surfactant that may be used in the complex, but are not limited to, include brassicamidopropyl dimethylamine, lauramidopropyl dimethylamine, myristamidopropyl dimethylamine, stearamidopropyl dimethylamine, cocamidopropyl dimethylamine, ricinolamidopropyl dimethylamine, isostear amidopropyl dimethylamine, oleamidopropyl dimethylamine, behenamidopropyl dimethylamine, and palmamidopropyl dimethylamine.

[0047] In a preferred embodiment the amidoamine functionalized surfactant of the antioxidant complex comprises alpha lipoic acid or its derivative with stearamidopropyl dimethylamine.

[0048] The anti-oxidant complex is a salt form of amidoamine lipoate complex, and is soluble in water when the complex comprises amidoamine functionalized surfactant to alpha lipoic acid at a specific molar ratio of 1: 1 and 1:2.

[0049] In an embodiment, there is provided a water-soluble amidoamine lipoate complex, which comprises amidoamine functionalized surfactant and alpha Lipoic acid at a specific molar ratio of 1:2.

[0050] In a preferred embodiment, the water-soluble amidoamine lipoate complex comprises amidoamine functionalized surfactant and alpha Lipoic acid at a molar ratio of 1:1.

[0051] The amidoamine lipoate complex comprising amidoamine functionalized surfactant and alpha lipoic acid at a molar ratio of 1 : 1 provide significant protection against hair protein damage during chemical treatments.The hair damage repair composition comprises effective amount of an aqueous solution of amidoamine alpha lipoate complex salt.

[0052] The amidoamine-alpha lipoic acid complex salt interacts with hair keratinous substrate through multiple binding sites and provide targeted repair and protection to chemically treated hair. The binding process helps in protecting and repairing the cuticle layer of the hair, thus preventing further damage and improving the overall condition of the hair.

[0053] The hair damage repair composition comprises an aqueous solution of 0.001% to 5% amidoamine lipoate complex.

[0054] The present hair damage repair composition is formulated in various hair care formulations for imparting its hair protective effect, by mixing the aqueous solution of the active amidoamine lipoate complex with other formulation excipients.

[0055] In an embodiment there is provided a hair care formulations comprising a hair damage repair composition containing 0.05-1% amidoamine lipoate complex along with formulation excipients.

[0056] The hair care formulations, formulated to incorporate the present hair damage repair composition, are selected from leave-on sprays, hair oils, or in combination with shampoos, hair conditioning spray and rinse-off conditioners designed to be applied before, during, or after chemical treatments.

[0057] The formulation excipients, are commonly used excipients required for formulating hair care formulations, and are selected from anionic and amphoteric surfactants, cationic surfactants, permanent free cationic amidoamine, conditioning agents, silicones, fatty alcohols, humectants, oils and emollients, thickeners, chelating agents, preservatives, pH adjusters, and solvents.The anionic and amphoteric surfactants provide the cleansing and foaming effect in a hair care formulation. The anionic and amphoteric surfactant, which can be combined with the hair damage repair composition to develop a hair care formulation, is selected from Sodium lauroyl sarcosinate, Sodium laureth sulfate, Cocamidopropyl betaine, Sodium cocoyl isethionate.

[0058] The cationic surfactants provide the conditioning, antistatic and hair fiber substantive effect in a hair care formulation. The cationic surfactants, which can be combined with the hair damage repair composition to develop a hair care formulation, is selected from Cetrimonium chloride, Behentrimonium chloride, S tear amidopropyldimethylamine.

[0059] The permanent cationic amidoamine, which can be combined with the hair damage repair composition to develop a hair care formulation, is selected from bis-(Isostearoyl / Oleoyl Isopropyl) dimonium methosulfate, Cetrimonium Methosulfate, Distearoylethyl Hydroxyethylmonium Methosulfate, Quatemium-33, behenamidopropyl ethyldimonium ethosulfate, behenamidopropyl PG-dimonium chloride, oleamidopropyl ethyldimonium ethosulfate, oleamidopropyl PG-dimonium chloride, cocamidopropyl ethyldimonium ethosulfate, cocamidopropyltrimonium chloride, ricinoleamidopropyl ethyldimonium ethosulfate, ricinoleamidopropyltrimonium chloride, ricinoleamidopropyltrimonium methosulfate, stearamidopropyl ethyldimonium ethosulfate, stearamidopropyl trimonium methosulfate, undecyleneamidopropyltrimonium methosulfate, lauramidopropyl PG-dimonium chloride, and canolamidopropyl ethyldimonium ethosulfate, with preferred cationic amidoamines being Bis-(Isostearoyl / Oleoyl Isopropyl) Dimonium Methosulfate, Cetrimonium Methosulfate, and Distearoylethyl Hydroxyethylmonium Methosulfate.

[0060] The conditioning agents provide the effect of conditioning, and detangling of hairs in a hair care formulation. The conditioning agents, which can be combined withthe hair damage repair composition to develop a hair care formulation, is selected from Cetrimonium chloride, Behentrimonium methosulfate, Polyquatemium-7, Polyquatemium-73, Polyquatemium-10, Guar Hydroxytrimonium Chloride.

[0061] The silicones provide the effect of conditioning, shine, smoothness, and frizz control in a hair care formulation. The silicones, which can be combined with the hair damage repair composition to develop a hair care formulation, is selected from Amodimethicone, Dimethicone, Dimethiconol, Cyclopentasiloxane, Phenyl Trimethicone.

[0062] The Fatty Alcohols are added in hair care formulation for viscosity control, and for as emollient. The Fatty Alcohols, which can be combined with the hair damage repair composition to develop a hair care formulation, is selected from Cetyl alcohol, Stearyl alcohol, Cetearyl alcohol.

[0063] The Humectants are added in hair care formulation for moisture retention. The Humectants which can be combined with the hair damage repair composition to develop a hair care formulation, is selected from Glycerin, Propylene glycol, Sorbitol.

[0064] In a preferred embodiment there is provided a hair spray composition comprising an aqueous solution of stearamidopropyl dimethylamine alpha-lipoate complex at a weight percentage ranging from 0.05% to 1% as an active agent, along with additional formulation excipients.

[0065] In a preferred embodiment there is provided a hair shampoo composition comprising an aqueous solution of stearamidopropyl dimethylamine alpha-lipoate complex at a weight percentage ranging from 0.05% to 1% as an active agent, along with additional formulation excipients.In a preferred embodiment there is provided a hair conditioner composition comprising an aqueous solution of stearamidopropyl dimethylamine alpha-lipoate complex at a weight percentage ranging from 0.05% to 1% as an active agent, along with additional formulation excipients.

[0066] In a preferred embodiment there is provided a hair mask composition comprising an aqueous solution of stearamidopropyl dimethylamine alpha-lipoate complex at a weight percentage ranging from 0.05% to 1% as an active agent, along with additional formulation excipients.

[0067] In an embodiment there is provided a method for preparation of a hair damage repair composition.

[0068] The method for preparation of a hair damage repair composition comprises steps of:

[0069] i. preparing amidoamine-alpha lipoate complex, and

[0070] ii. preparing the aqueous solution of the amidoamine-alpha lipoate complex.

[0071] The present invention provides a method for preparation of amidoamine-alpha lipoate complex comprising mixing amidoamine functionalized surfactant, and alpha- lipoic acid in an organic solvent.

[0072] The method for preparation of amidoamine-alpha lipoate complex involves mixing amidoamine functionalized surfactant and alpha- lipoic acid at a specific molar ratio of 1:1 and 1:2, in solvent.

[0073] The complex of alpha-lipoic acid and amidoamine works synergistically to provide deep conditioning, protect against oxidative stress, and promote the recovery of the hair’s structural integrity. The solvent ensures that the active ingredient amidoamine alpha- lipoate is properly solubilized and ensures its even distribution in the hair. The solubilized complex penetrates the hair for optimal performance.The solvent as used in the preparation of amidoamine-alpha lipoate complex is selected from the group comprising propylene glycol, butylene glycol or propane-1,2-diol.

[0074] In a preferred embodiment, the solvent is propylene glycol.

[0075] In one embodiment, the hair damage repair composition is provided as a hair protecting agent in a hair treatment kit comprising the hair damage repair composition with different sets of products applied before, during, and / or after chemical treatments to protect and repair the hair.

[0076] In an embodiment, there is provided a hair treatment kit comprising

[0077] a) a hair damage repair composition comprising aqueous solution of amidoamine-alpha lipoate complex,

[0078] b) an oxidizing agent,

[0079] c) a colorant, and

[0080] d) a surfactant.

[0081] In an embodiment, the hair treatment kit is a hair styling treatments kit comprising a) a hair damage repair composition comprising water solubilized form of amidoamine-alpha lipoate complex,

[0082] b) a reducing agent,

[0083] c) an oxidizing agent, and

[0084] d) a surfactant.

[0085] The present invention is further illustrated in Examples.

[0086] EXAMPLES

[0087] Raw Material: Alpha-lipoic acid sourced from Jiangsu Tohope Pharmaceutical Co., Ltd., stearamidopropyl dimethylamine from Croda International Pic, and propylene glycol from Swadesh Chemicals. The ingredient amounts in the compositions are expressed in % by weight, based on the total weight of the cosmetic composition.Example 1: Preparation of Anti-oxidant complex

[0088] The Alpha lipoic acid, Stearamidopropyl dimethylamine, water and propylene glycol are mixed at varied proportion as shown in Table 1. Table 1 demonstrate that effective ionic complex formation between a-lipoic acid and the amidoamine is critically dependent on the molar ratio.

[0089] Table 1: Effect of Molar Ratio on Complex Formation and Solubility

[0090]

[0091] Stearamidopropyl dimethylamine is insoluble in both water (Figure 1(a)) and propylene glycol solvent (Figure 1(b)). Alpha-lipoic acid on the other hand is insoluble in water (Figure 1(c)), while soluble in propylene glycol solvent (Figure 1(d)). Stearamidopropyl dimethylamine (2 g), and Alpha-lipoic acid (1.11 g) was mixed with propylene glycol (20 ml) at 1 : 1 mol ratio and at 1 :2 mol ratio and heated slightly to form a water soluble form amidoamine alpha lipoate complex. Figure 1(e) and Figure 1(f) shows water-soluble Stearamidopropyldimethylamine-Eipoate complex prepared with propylene glycol at 1:1 molar ratio and 1:2 molar ratio respectively.

[0092] Ratio of 1:1 provides clear solutions, characteristic ammonium signals in

[0093]

[0094] NMR, and acceptable aqueous solubility, and used for further analysis. Deviation fromthese ratios results in incomplete proton transfer, reduced solubility, or precipitation due to excess free acid or amine, confirming that non- stoichiometric ratios do not yield a stable complex.

[0095] Example 2: Physicochemical Characteristics of the Anti-oxidant complex NMR Characterization of Alphalipoic Acid

[0096] 1H NMR (400 MHz, CDC13) 83.58 (m, J = 12.7, 6.4 Hz, 1H), 3.24 - 3.07 (m, 2H), 2.53 - 2.42 (m, 1H), 2.38 (t, J = 7.4 Hz, 2H), 1.92 (m, J = 13.8, 6.9 Hz, 1H), 1.78 -1.63 (m, 4H), 1.50 (m, J = 9.2, 6.8 Hz, 2H).

[0097] The recordedrH NMR spectrum (Figure 2) is consistent with the known structure of a-lipoic acid, showing characteristic multiplets corresponding to the dithiolane ring methine and methylene protons as well as the aliphatic side-chain methylene groups. Notably, the carboxylic acid (-COOH) proton signal, typically expected in the region of 6 10-12 ppm, is not observed in the spectrum recorded in CDCk This absence is attributable to rapid proton exchange and strong intermolecular hydrogen bonding of the carboxylic acid proton, which commonly results in severe line broadening or complete suppression of the -COOH resonance under non-hydrogen-bond-disrupting solvent conditions. Such behavior of the carboxylic acid proton in CDCh is well documented and does not affect confirmation of molecular identity. The remaining proton signals and their chemical shifts are fully consistent with a-lipoic acid and confirm the integrity of the compound.

[0098] NMR Characterization of Stearamidopropyldimethylamine

[0099] 1H NMR (400 MHz, CDC13) 67.26 (s, residual CHCh), 3.35-3.10 (m, 4H), 2.55-2.30 (m, 6H), 2.10-1.95 (m, 2H), 1.75-1.55 (m, 2H), 1.50-1.30 (br m, ~28H), 0.88 (t, J ~ 6.8 Hz, 3H).TheLH NMR spectrum (Figure 3) is consistent with the structure of stearamidopropyldimethylamine and shows the expected resonances for a long-chain fatty amide bearing a tertiary dimethylamine functionality.

[0100] • 5 3.35-3.10 ppm (multiplet) corresponds to methylene protons adjacent to the tertiary amine nitrogen (-N-CH2-), characteristic of an unprotonated tertiary amine.

[0101] • 5 2.55-2.30 ppm (multiplet) includes the N-methyl protons (-N(CHs)2) and adjacent methylene protons of the propyl linker.

[0102] • 52.10-1.95 ppm is attributed to methylene protons adjacent to the amide carbonyl (-CO-CH2).

[0103] • 5 1.75-1.30 ppm represents the long aliphatic methylene chain of the stearamide moiety.

[0104] • 5 0.88 ppm (triplet) corresponds to the terminal methyl group of the Cis alkyl chain.

[0105] Notably, no resonance is observed in the 5 9-10 ppm region, confirming that the tertiary amine is present in its free base (unprotonated) form. This absence clearly distinguishes the free base from the corresponding a-lipoate salt, wherein a diagnostic ammonium (R.3NH ) proton signal appears in the downfield region.

[0106] NMR Characterization of Stearamidopropyldimethylamine- Alpha lipoate Salt 1H NMR (400 MHz, CDC13) 59.74 (s, 1H), 6.99 (s, 1H), 3.65 - 3.50 (m, 1H), 3.30 (m, J = 12.1, 5.7 Hz, 2H), 3.21 - 3.05 (m, 2H), 2.71 (m, J = 7.0 Hz, 2H), 2.50 - 2.38 (m, 7H), 2.27 (m, J = 14.0, 6.7 Hz, 2H), 2.21 - 2.13 (m, 2H), 1.95 - 1.86 (m, 1H), 1.86 - 1.76 (m, 2H), 1.75 - 1.55 (m, 5H), 1.55 - 1.38 (m, 2H), 1.26 (d, J = 12.1 Hz, 28H), 0.87 (t, J = 6.8 Hz, 3H).

[0107] TherH NMR spectrum (Figure 4) of the stearamidopropyldimethylamine-a- lipoate complex confirms the formation of an ionic ammonium carboxylate salt rather than a physical mixture of the starting materials. A distinct singlet at 59.74 ppm (1H) isobserved, which is assigned to the protonated tertiary amine (RsNH+) of stearamidopropyldimethylamine. The presence of this downfield, exchange-broadened proton resonance is characteristic of an ammonium species formed by proton transfer from a-lipoic acid to the tertiary amine, and is not present in the free base form of stearamidopropyldimethylamine. This signal in the 9-10 ppm region serves as direct spectroscopic evidence of protonation of the diamine moiety and confirms salt formation. The formation of ionic salt is confirmed by:

[0108] • Downfield shifting and broadening of N-adjacent methylene and methyl protons in the region of 5 2.7-3.3 ppm, consistent with protonation of the tertiary amine nitrogen.

[0109] • Absence of a carboxylic acid (-COOH) proton signal of a-lipoic acid in the 5 10-12 ppm region, indicating conversion of the acid to its carboxylate (COO ) form.

[0110] • Retention of characteristic aliphatic chain signals of stearamidopropyldimethylamine (5 1.26 ppm, long-chain methylenes; 50.87 ppm, terminal methyl), confirming structural integrity.

[0111] FTIR Characteristics of Alphalipoic Acid

[0112] A strong absorption observed in the region of 1686 cm1is assigned to the carboxylic acid carbonyl (C=O) stretching vibration (Figure 5). This peak is a diagnostic and characteristic absorption confirming the presence of the free carboxylic acid functionality in a-lipoic acid. The FTIR spectrum of a-lipoic acid is characterized by a strong carboxylic acid carbonyl absorption at 1686 cm1confirming the presence of carboxylic acid group.

[0113] FTIR Characteristics of Stearamidopropyldimethylamine

[0114] A broad absorption band at approximately 3303 cm1is attributed to N-H stretching vibrations of the amide group, indicating the presence of a secondary amide linkage within the molecule. A characteristic amide carbonyl (C=O) stretching vibration is observed at 1637 cm which serves as a diagnostic peak for the amide functionality and confirms successful formation of the amide linkage between stearic acid and the propylamine moiety. The absorption band at 1549 cm1is assigned to amide IIvibrations, arising from a combination of N-H bending and C-N stretching, further substantiating the presence of an amide group. The FTIR spectral data clearly confirm the presence of amide (-CONH-), which are consistent with the chemical structure of Stearamidopropyldimethylamine. The observed characteristic peaks (Figure 6), particularly the amide carbonyl absorption at -1637 cm serve as key identifying features of the compound and validate its structural integrity and chemical identity.

[0115] FTIR Characteristics of Stearamidopropyldimethylamine-Alpha lipoate Salt A broad absorption band at approximately 3303 cm1is attributed to hydrogen-bonded N-H stretching vibrations of the amide group and associated ionic interactions within the salt structure. The amide carbonyl (C=O) stretching vibration appears at 1650

[0116]

[0117] consistent with the amide linkage originating from stearamidopropyldimethylamine. Notably, the carboxylic acid C=O stretching band of a-lipoic acid (normally observed at 1686 cm ') is absent in the salt spectrum. Absorption bands at 1568 cm1and 1331 cm which are assigned to asymmetric and symmetric stretching vibrations of the carboxylate anion (-COO") (Figure 7). This shift is a key diagnostic indicator of salt formation.

[0118] Example 3: Surface damage analysis of Anti-oxidant complex

[0119] Hair tresses were treated with a commercially available blonde hair lightener to damage the hair (Figure 8(a)). The damaged hair was then treated with samples as shown in Table 2 for the effect on cuticle condition. The base formulation is a hair care formulation without having the antioxidant complex.

[0120] Table 2: Reduction of Surface Damage (SEM-Based Observation)

[0121]

[0122]

[0123] After the treatment, the hair was air-dried, and SEM images were recorded (Figure 8(b)). Co- treatment with the complex of Example 1 following the chemical treatment resulted in a reduction of surface damage, demonstrating the damage prevention efficacy of the complex. These results underscore the damage prevention efficacy of the complex, highlighting its potential as an effective treatment for minimizing damage caused by chemical hair treatments.

[0124] The results demonstrate that the a-lipoic acid-amidoamine complex effectively binds to chemically damaged hair, resulting in reduced surface damage, improved cuticle integrity, and enhanced conditioning properties. Compared to free alpha-lipoic acid, the complex shows superior deposition and conditioning performance. The observations are consistent with the SEM images illustrated in Fig. 8A (damaged hair) and Fig. 8B.

[0125] Example 4: Preparation of hair damage repair composition

[0126] Hair damage repair composition was prepared with 1:1 complex at varied concentration in water as shown in Table 3 below, and tested for formulation stability.

[0127] Table 3: Complex Concentration Optimization

[0128]

[0129] >

[0130]

[0131] Table 3 shows that the complex in composition is stable at a concentration range of 0.001-5%. An increase in concentration beyond 5% leads to unstable composition, and therefore is not suitable for formulation.

[0132] Example 5: Hair Spray Composition containing the anti-oxidant complex

[0133] A stable hair spray composition was prepared comprising an active propylene glycol Stearamidopropyldimethylamine Lipoate active, along with cosmetically acceptable carriers and auxiliaries as shown in Table 4.

[0134] Table 4: Hair Spray Composition

[0135]

[0136] Example 6: Hair Shampoo Composition containing the anti-oxidant complex A stable hair shampoo composition was prepared comprising an active propylene glycol stearamidopropyldimethylamine lipoate active, along with cosmetically acceptable carriers and auxiliaries as shown in Table 5.Table 5: Hair Shampoo Composition

[0137]

[0138] Example 7: Hair Conditioner Composition containing the anti-oxidant complex

[0139] A stable hair conditioner composition was prepared comprising an active propylene glycol stearamidopropyldimethylamine lipoate active, along with cosmetically acceptable carriers and auxiliaries as shown in Table 6.

[0140] Table 6: Hair Conditioner Composition

[0141]

[0142]

[0143] Example 8: Hair Mask Composition containing the anti-oxidant complex A stable hair mask composition was prepared comprising an active propylene glycol (and) stearamidopropyldimethylamine lipoate active, along with cosmetically acceptable carriers and auxiliaries as shown in Table 7.

[0144] Table 7: Hair Mask Composition

[0145]

[0146]

[0147] ADVANTAGE OF THE INVENTION

[0148] The present invention provides an innovative composition that effectively reduces damage to hair following chemical treatments. By using a combination of alpha-lipoic acid and amidoamines, in along with optimized solvent concentrations and molar ratios, the composition binds to the hair and provides targeted repair, and improving the overall health and appearance of the hair. The composition is versatile and can be used as part of a treatment kit for various chemical treatments, ensuring that the hair remains protected and restored throughout the treatment process.

Claims

CLAIMS:

1. A hair damage repair composition comprising an aqueous solution of an antioxidant complex as a hair protective agent, wherein the antioxidant complex comprises amidoamine functionalized surfactant and alpha-lipoic acid.

2. The hair damage repair composition as claimed in claim 1, wherein the antioxidant complex comprises amidoamine functionalized surfactant and alpha-lipoic acid at a ratio 1:1 and 1:2.

3. The hair damage repair composition as claimed in claim 1, wherein the amidoamine functionalized surfactant is selected from brassicamidopropyl dimethylamine, lauramidopropyl dimethylamine, myristamidopropyl dimethylamine, stearamidopropyl dimethylamine, cocamidopropyl dimethylamine, ricinolamidopropyl dimethylamine, isostearamidopropyl dimethylamine, oleamidopropyl dimethylamine, behenamidopropyl dimethylamine, and palmamidopropyl dimethylamine.

4. The hair damage repair composition as claimed in claim 1, comprises 0.001-5% wt of the antioxidant complex along with additional formulation excipient in the composition.

5. The hair damage repair composition as claimed in claim 1, wherein the antioxidant complex is soluble in water.

6. The hair damage repair composition as claimed in claim 4, wherein the additional formulation excipient is selected from anionic and amphoteric surfactants, cationic surfactants, permanent free cationic amidoamine, conditioning agents, silicones, fatty alcohols, humectants, oils and emollients, thickeners, chelating agents, preservatives, pH adjusters, and solvents.

7. The hair damage repair composition as claimed in claim 6, wherein the anionic and amphoteric surfactant is selected from Sodium lauroyl sarcosinate, Sodium laureth sulfate, Cocamidopropyl betaine, Sodium cocoyl isethionate.

8. The hair damage repair composition as claimed in claim 6, wherein the cationic surfactant is selected from Cetrimonium chloride, Behentrimonium chloride, S tearamidopropyldimethylamine .

9. The hair damage repair composition as claimed in claim 6, wherein the permanent cationic amidoamine is selected from bis-(Isostearoyl / Oleoyl Isopropyl) dimonium methosulfate, Cetrimonium Methosulfate, Distearoylethyl Hydroxyethylmonium Methosulfate, Quaternium-33, behenamidopropyl ethyldimonium ethosulfate, behenamidopropyl PG-dimonium chloride, oleamidopropyl ethyldimonium ethosulfate, oleamidopropyl PG-dimonium chloride, cocamidopropyl ethyldimonium ethosulfate, cocamidopropyltrimonium chloride, ricinoleamidopropyl ethyldimonium ethosulfate, ricinoleamidopropyltrimonium chloride, ricinoleamidopropyltrimonium methosulfate, stearamidopropyl ethyldimonium ethosulfate, stearamidopropyl trimonium methosulfate, undecyleneamidopropyltrimonium methosulfate, lauramidopropyl PG-dimonium chloride, and canolamidopropyl ethyldimonium ethosulfate, with preferred cationic amidoamines being Bis-(Isostearoyl / Oleoyl Isopropyl) Dimonium Methosulfate, Cetrimonium Methosulfate, and Distearoylethyl Hydroxyethylmonium Methosulfate.

10. The hair damage repair composition as claimed in claim 6, wherein the conditioning agent is selected from Cetrimonium chloride, Behentrimonium methosulfate, Polyquatemium-7, Polyquaternium-73, Polyquatemium-10, Guar Hydroxytrimonium Chloride.

11. The hair damage repair composition as claimed in claim 6, wherein the silicones is selected from Amodimethicone, Dimethicone, Dimethiconol, Cyclopentasiloxane, Phenyl Trimethicone.

12. The hair damage repair composition as claimed in claim 6, wherein the Fatty Alcohol is selected from Cetyl alcohol, Stearyl alcohol, Cetearyl alcohol.

13. The hair damage repair composition as claimed in claim 6, wherein the Humectants is selected from Glycerin, Propylene glycol, Sorbitol.

14. A water-soluble antioxidant complex for hair damage repair composition comprising amidoamine functionalized surfactant and alpha-lipoic acid at a ratio 1:1 and 1:2 in an organic solvent.

15. The water soluble antioxidant complex as claimed in claim 14, wherein the organic solvent is selected from propylene glycol, butylene glycol or propane- 1,2-diol.

16. A water-soluble antioxidant complex for hair damage repair composition comprising stearamidopropyl dimethylamine and alpha-lipoic acid at a ratio 1 : 1 in propylene glycol.

17. A water-soluble antioxidant complex for hair damage repair composition comprising stearamidopropyl dimethylamine and alpha-lipoic acid at a ratio 1:2 in propylene glycol.

18. A hair spray composition comprising an aqueous solution of stearamidopropyl dimethylamine alpha-lipoate complex at a weight percentage ranging from 0.05% to 1% as an active agent, along with additional formulation excipients.

19. A hair shampoo composition comprising an aqueous solution of stearamidopropyl dimethylamine alpha-lipoate complex at a weight percentage ranging from 0.05% to 1% as an active agent, along with additional formulation excipients.

20. A hair conditioner composition comprising an aqueous solution of stearamidopropyl dimethylamine alpha-lipoate complex at a weight percentage ranging from 0.05% to 1% as an active agent, along with additional formulation excipients.

21. A hair mask composition comprising an aqueous solution of stearamidopropyl dimethylamine alpha-lipoate complex at a weight percentage ranging from 0.05% to 1% as an active agent, along with additional formulation excipients.

22. A method for preparation of the hair damage repair composition as claimed in preceding claim, comprising steps of:i. preparing an antioxidant complex of claim 1, andii. dissolving the complex in water to form an aqueous solution of the complex.

23. The method as claimed in claim 22, wherein the step (i) comprises combining amidoamine functionalized surfactant and alpha-lipoic acid in organic solvent at a ratio of 1:1 and 1:2.

24. The method as claimed in claim 22 to 23, wherein the organic solvent is selected from the group comprising propylene glycol, butylene glycol or propane- 1,2-diol.

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