Isoamyl esters for hair thermal protection

Abstract

The present disclosure provides a hair care composition that provides thermal protection of hair fibers. The hair care composition comprises an isoamyl ester derived from renewable sources. Methods of protecting hair from thermal damage using the composition and a hair styling system incorporating the composition are also disclosed.

Description

ISOAMYL ESTERS FOR HAIR THERMAL PROTECTION TECHNICAL FIELD

[0001] The present disclosure relates to hair care compositions, and more particularly to isoamyl ester compounds derived from renewable sources for providing thermal protection to hair fibers during heat styling processes.BACKGROUND

[0002] Emollients, including esters, are used in personal care formulations for various purposes such as moisturizing, texture enhancement, and spreadability. Conventional emollients include mineral oils, silicones, and petroleum-derived esters. There is interest in developing emollients from renewable sources for use in hair care and other personal care applications.SUMMARY

[0003] According to an aspect of the present disclosure, a hair care composition is provided. The hair care composition includes an isoamyl ester compound of Formula I: R1-COO-R2, wherein R1 represents a fatty acid chain derived from caprylic, capric, cocoate, palmitic, or stearic acids, having carbon chain lengths of C8, CIO, C12, Cl 6, or Cl 8 respectively, and R2 represents the isoamyl group derived from isoamyl alcohol, having the structure (CH3)2CHCH2CH2-. The composition also includes a cosmetically acceptable carrier. The composition provides thermal protection to hair fibers.

[0004] According to other aspects of the present disclosure, the hair care composition may include one or more of the following features. R1 may be derived from caprylic acid and have a carbon chain length of C8. R1 may be derived from capric acid and have a carbon chain length of CIO. R1 may be derived from cocoate acid and have a carbon chain length of Cl 2. R1 may be derived from palmitic acid and have a carbon chain length of Cl 6. R1 may bederived from stearic acid and have a carbon chain length of Cl 8. The composition may further include a silicone compound.

[0005] According to another aspect of the present disclosure, a hair care composition is provided. The hair care composition includes a mixture of a first thermal protective agent and a second thermal protective agent. The first thermal protective agent and the second thermal protective agent are each an isoamyl ester compound having a formula CH3(CH2)nCOOCH2CH(CH3)2, wherein n is an integer from 6 to 16, and wherein the first thermal protective agent is different from the second thermal protective agent.

[0006] According to other aspects of the present disclosure, the hair care composition may include one or more of the following features. The value of n may be selected from the group consisting of 6, 8, 10, 14, and 16. The composition may further include a silicone compound.

[0007] According to another aspect of the present disclosure, a method for protecting hair from thermal damage is provided. The method includes applying to hair a composition comprising an isoamyl ester compound of Formula I: Rl-COO-R2 wherein n is an integer from 6 to 16, wherein: n=6 for Caprylate (C8:0), n=8 for Caprate (C10:0), n=10-16 for Cocoate (mixture of fatty acids, mainly C12-C18), n=14 for Palmitate (C16:0), and n=16 for Stearate (C18:0). The method also includes exposing the hair to heat from a heat styling device.

[0008] According to other aspects of the present disclosure, the method may include one or more of the following features. The value of n may be 6, corresponding to isoamyl caprylate. The value of n may be 8, corresponding to isoamyl caprate. The value of n may be 14, corresponding to isoamyl palmitate. The value of n may be 16, corresponding to isoamyl stearate. The composition may further include a silicone compound. The silicone compound may be selected from the group consisting of dimethicone, cyclomethicone, and amodimethicone .

[0009] According to another aspect of the present disclosure, a hair styling system is provided. The hair styling system includes a heat styling device and a hair care composition comprising an isoamyl ester compound selected from the group consisting of isoamyl caprylate / caprate, isoamyl cocoate, and isoamyl palmitate / stearate. The hair care composition is configured to be applied to hair prior to using the heat styling device to provide thermal protection to the hair.

[0010] According to other aspects of the present disclosure, the hair styling system may include one or more of the following features. The isoamyl ester compound may be isoamyl caprylate / caprate represented by the formula CH3(CH2)nCOOCH2CH(CH3)2 wherein n is 6 or 8. The isoamyl ester compound may be isoamyl cocoate represented by the formula CH3(CH2)nCOOCH2CH(CH3)2 wherein n is an integer from 10 to 16. The heat styling device may be selected from the group consisting of a flat iron, curling iron, and blow dryer.

[0011] The foregoing general description of the illustrative embodiments and the following detailed description thereof are merely exemplary aspects of the teachings of this disclosure and are not restrictive.BRIEF DESCRIPTION OF FIGURES

[0012] The disclosure can be understood in consideration of the following detailed description of various embodiments in connection with the accompanying drawings.

[0013] FIG. 1 illustrates a cross-sectional view of a hair follicle structure, according to aspects of the present disclosure.

[0014] FIG. 2 shows a chemical reaction diagram depicting an amino acid condensation reaction, according to an embodiment.

[0015] FIG. 3 presents a structural diagram showing molecular interactions in keratin, according to aspects of the present disclosure.

[0016] FIG. 4 displays a cross-sectional view of a hair shaft structure, according to an embodiment.

[0017] FIG. 5 depicts a thermogravimetric analysis curve showing thermal decomposition behavior, according to aspects of the present disclosure.

[0018] FIG. 6 illustrates another thermogravimetric analysis curve showing thermal decomposition behavior, according to an embodiment.

[0019] FIG. 7 shows a thermogravimetric analysis curve demonstrating thermal decomposition behavior, according to aspects of the present disclosure.

[0020] FIG. 8 depicts another thermogravimetric analysis curve demonstrating thermal decomposition behavior, according to an embodiment.

[0021] FIG. 9 illustrates a thermogravimetric analysis curve showing thermal decomposition behavior, according to aspects of the present disclosure.

[0022] FIGS. 10A-10G show optical microscopy images of hair strands after various treatments, according to embodiments.

[0023] FIG. 11 depicts a differential scanning calorimetry thermogram showing thermal analysis results, according to an aspect of the present disclosure.

[0024] FIG. 12 illustrates another differential scanning calorimetry thermogram showing thermal analysis results, according to an embodiment.

[0025] FIG. 13 shows a differential scanning calorimetry thermogram displaying thermal analysis results, according to aspects of the present disclosure.

[0026] FIG. 14 depicts another differential scanning calorimetry thermogram displaying thermal analysis results, according to an embodiment.

[0027] FIG. 15 illustrates a differential scanning calorimetry analysis curve showing thermal events for a hair sample, according to aspects of the present disclosure.

[0028] FIG. 16 shows another differential scanning calorimetry analysis curve showing thermal events for a hair sample, according to an embodiment.

[0029] FIG. 17 is a graph illustrating example differential scanning calorimetry thermogram results for hair strands treated with isoamyl cocoate.

[0030] FIG. 18 is a graph illustrating example differential scanning calorimetry thermogram results for hair strands treated with isoamyl caprylate / caprate .

[0031] FIG. 19 is a graph illustrating example differential scanning calorimetry thermogram results for hair strands treated with isoamyl palmitate / stearate .

[0032] FIG. 20 is a graph illustrating example differential scanning calorimetry thermogram results for hair strands treated with hemisqualane .

[0033] FIG. 21 is a graph illustrating example differential scanning calorimetry thermogram results for hair strands treated with cyclomethicone.

[0034] FIG. 22 is a graph illustrating example differential scanning calorimetry thermogram results for hair strands treated with bis-cetearyl amodimethicone .

[0035] FIG. 23 is a graph illustrating example differential scanning calorimetry thermogram results for hair strands treated with coconut oil.

[0036] FIG. 24 is a graph illustrating example differential scanning calorimetry thermogram results for hair strands treated with mineral oil.

[0037] FIG. 25 is a graph illustrating example differential scanning calorimetry thermogram results for hair strands treated with diisoamyl succinate.DETAILED DESCRIPTION

[0038] For purposes of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiments illustrated in the drawings, and specific language will be used to describe the same. It will nonetheless be understood that no limitation of the scope of the disclosure is intended by the illustration and description of certain embodiments of the disclosure. In addition, any alterations and / or modifications of the illustrated and / or described embodiment(s) are contemplated as being within the scope of the present disclosure. Further, any other applications of the principles of thedisclosure, as illustrated and / or described herein, as would normally occur to one skilled in the art to which the disclosure pertains, are contemplated as being within the scope of the present disclosure.

[0039] Thermal protection can be important in modern hair care, given the widespread use of heat styling tools such as blow dryers, flat irons, and curling wands. Repeated exposure to high temperatures can lead to the degradation of the hair’s natural proteins and lipids, causing dryness, brittleness, and split ends.

[0040] The present disclosure relates to hair care compositions that provide thermal protection to hair fibers. The hair compositions may include an emollient that may provide thermal protection to hair fibers. In particular, the compositions comprise isoamyl ester compounds derived from renewable sources. These isoamyl ester compounds may be represented by Formula I: R1-COO-R2 In Formula I, R1 may represent a fatty acid chain derived from various natural sources, while R2 may represent an isoamyl group derived from isoamyl alcohol. The fatty acid chain R1 may have different carbon chain lengths, providing a range of isoamyl ester compounds with varied properties. In some cases, the isoamyl alcohol may be a naturally occurring alcohol, such as that derived from sugar cane. In some cases, the fatty acid may be a vegetal fatty acid. In some cases, the fatty acid may be derived from vegetable oil, coconut oil, palm oil, palm kernel oil, etc. Distinct fatty acid chain length cuts are used for producing these emollients, providing them with different sensory properties (spreadability and feeling of greasiness, for example), enabling formulators to design innovative and sustainable formulations for the personal care market.

[0041] The hair care compositions may include a cosmetically acceptable carrier along with the isoamyl ester compound. This combination allows for effective application and distribution of the thermal protection agent throughout the hair fibers.

[0042] Isoamyl ester compounds may be at least 50%, at least 75%, or 100% derived from renewable sources. At least 30 wt%, at least 50 wt%, at least 751 / 48wt% of the hair composition is from renewable sources. This aligns with growing consumer demand for sustainable and environmentally responsible personal care products.

[0043] The development of these isoamyl esters is based on a Greenformance concept, which associates sustainability with performance. This approach aims to deliver high-performing hair care products while minimizing environmental impact.

[0044] FIG. 1 illustrates a cross-sectional view of a hair follicle structure. Hair fibers are composed primarily of keratin, a protein organized into coiled helices that form the structural framework of the hair shaft. The hair shaft includes an outer cuticle layer of overlapping scales that protects the inner cortex, which contains the keratin fibers responsible for hair strength and elasticity. When hair is exposed to high temperatures during heat styling, thermal damage may occur through disruption of hydrogen bonds and protein structures within the hair, leading to dehydration, cuticle damage, and increased brittleness. The isoamyl ester compounds disclosed herein may provide thermal protection by forming a protective barrier on the hair surface and interacting with the hair's protein structure to help preserve hair integrity during heat exposure.

[0045] As shown in FIG. 2, keratin is a high molecular weight polypeptide composed of chains formed by the condensation of L-amino acids. The bond formed through condensation that links amino acids is known as a peptide bond. The polypeptide chain becomes the structure of the a-keratin fiber. The R1 and R2 groups represent the side chains of the amino acid residues in a-keratin, corresponding to 18 different compositions of hair from the main human races.

[0046] The stability and properties of keratin are determined by various chemical bonds and interactions within its structure, as depicted in FIG. 3. The chemical bonds that determine the structure of keratin can be classified into five types: ionic bonds, hydrogen bonds, Van der Waals forces, peptide or ester bonds, and disulfide bonds.

[0047] FIG. 4 provides a detailed illustration of the hair fiber structure, showing the arrangement of the cuticle, cortex, and medulla layers. The cuticle forms the outermost layer of the hair shaft and consists of overlapping scales that protect the inner structures. The cortex, which makes up the bulk of the hair shaft, contains long keratin fibers that give hair its strength and elasticity. In some cases, the medulla may be present as a central core, though it is not always visible in human hair. This structural organization contributes to the hair’s overall properties and its response to external factors, including heat.

[0048] The cuticle (outer part) can serve as the main barrier to the penetration of chemical and enzymatic agents into the hair shaft and is also responsible for the hair’s surface properties. It is the outermost layer of hair fiber, composed of several similar cells. This structure significantly affects the permeation of substances into the hair. The surface of the cuticle cell is covered by a thin layer of lipids known as the layer. Between adjacent cells, these lipids are separated by the 5 layer of protein components. This triple structure between adjacent cells is called the cell membrane complex (CMC). The CMC is the only substructure that continuously fills the intercellular spaces of hair fiber, making it an important pathway for substance penetration.

[0049] When hair is exposed to high temperatures during heat styling processes, such as those from flat irons, curling irons, or blow dryers, thermal damage may occur. Heat can disrupt the hydrogen bonds and salt linkages that help maintain the hair’s structure, leading to changes in the keratin proteins. In some cases, prolonged or repeated exposure to high temperatures may cause the a-keratin structure to transform into [3-keratin, resulting in weakened and brittle hair.

[0050] Thermal damage may manifest in various ways, including dehydration of the hair shaft, lifting or damage to the cuticle scales, protein degradation in the cortex, changes in hair color or texture, and increased susceptibility to breakage and split ends.

[0051] To mitigate these effects, protective agents may be applied to the hair before heat styling. These agents may form a barrier on the hair surface, helping to distribute heat more evenly and reduce direct contact between the heating element and the hair fibers. In some cases, these protective agents may also help to retain moisture within the hair shaft, reducing the risk of dehydration during heat exposure.

[0052] Compositions containing isoamyl ester compounds may be applied to hair prior to heat styling to provide thermal protection. These compounds may interact with the hair surface and penetrate the cuticle layer, potentially offering protection against thermal damage. The method of protecting hair from thermal damage may involve applying such a composition to the hair and then exposing the treated hair to heat from styling devices such as flat irons, curling irons, or blow dryers.

[0053] The effectiveness of thermal protection agents may depend on factors such as their chemical structure, molecular weight, and ability to form a uniform film on the hair surface. In some cases, the protective effect may also be influenced by the agent’s thermal stability and its interaction with other components in the hair care formulation.

[0054] Understanding the structure of hair and the mechanisms of thermal damage provides a foundation for developing effective protective strategies. By incorporating suitable protective agents, such as isoamyl ester compounds, into hair care routines, it may be possible to minimize the negative effects of heat styling while maintaining the desired styling outcomes.

[0055] The personal care formulation (e.g., hair care formulation) may include one or more ingredients. In some examples, a personal care formulation may include a thermal protective agent. In some examples, a personal care formulation may include a thermal protective agent and an active ingredient. In some examples, a personal care formulation may include a thermal protective agent, an active ingredient, and one or more additives. The thermal protective agent maybe an emollient. The emollient may include an ester. The additive may include a cosmetically acceptable vehicle. The additive may include additional thermal protective agents. In some examples, a personal care formulation may include a first thermal protective agent and a second thermal protective agent. In some examples, a personal care formulation may include a first thermal protective agent, a second thermal protective agent, and an active ingredient. In some embodiments, a person care formulation may include a first thermal protective agent, a second thermal protective agent, an active ingredient, and a cosmetically acceptable vehicle.

[0056] The ester may be synthesized from an alcohol (e.g., amyl alcohol, isoamyl alcohol, etc.) and a fatty acid (e.g., vegetal oil). The alcohol (e.g., amyl alcohol, isoamyl alcohol, etc.) may be derived from sugar cane, which may be a widely-available natural raw material in Brazil. The fatty acids may be derived from a vegetable source, such as coconut or palm kernel. The fatty acid may be obtained from an environmentally responsible source. Distinct fatty acid chain length cuts may be used for producing these emollients, providing them with different sensory properties (e.g., spreadability and feeling of greasiness), enabling formulators to design innovative and sustainable formulations for the personal care market.

[0057] Isoamyl alcohol, also known as isopentyl alcohol or 3-methyl-l-butanol, is a branched five-carbon alcohol with the chemical formula (CHs^CHCH CH OH. Isoamyl alcohol may be used as a reactant in the esterification reaction to produce the isoamyl ester compounds. In some cases, isoamyl alcohol may be derived from sugar cane through fermentation and distillation processes, contributing to the sustainable nature of the resulting ester emollient.

[0058] The renewable source of isoamyl alcohol (e.g., from sugar cane) contributes to the sustainable nature of the resulting ester emollient, aligning with the growing demand for natural and environmentally responsible ingredients inpersonal care products. The use of sugar cane-derived isoamyl alcohol distinguishes it from synthetic or petroleum-derived alternatives, emphasizing the commitment to renewable resources in the formulation of the personal care product. Sugar cane may be a widely available natural raw material, particularly in Brazil, India, Thailand, and China. Sugar-cane derived isoamyl alcohol may impact the final properties of the moisturizing agent, including its molecular structure, polarity, and potential interactions with skin or hair.

[0059] The fatty acid used in the synthesis of the moisturizing agent may be derived from vegetable sources, such as coconut or palm kernel oil. Coconut oil may be derived from the meat of mature coconuts harvested from the coconut palm (Cocos nucifera), while palm kernel oil may be extracted from the kernel or seed of the oil palm fruit (Elaeis guineensis). These fatty acids are typically octanoic (caprylic) acid or decanoic (capric) acid, which correspond to chain lengths of 8 and 10 carbon atoms, respectively. The use of these medium-chain fatty acids contributes to the unique properties of the resulting ester emollient, including its spreadability, skin feel, and moisturizing capabilities. The choice of vegetable-derived fatty acids aligns with the goal of creating a sustainable, renewable ingredient for personal care formulations. The specific fatty acid used can impact the final properties of the moisturizing agent, such as its melting point, viscosity, and skin penetration characteristics. By utilizing fatty acids from environmentally responsible sources, the formulation further enhances its eco-friendly profile while maintaining high performance as an emollient in skincare applications.

[0060] The ester may have a formula R — C(=O) — O — Ri, where R — C(=O) represents an acyl group, R may be an alkyl or aryl group, and Ri represents an alkyl group. R — C(=O) includes a carbonyl group (C=O) bonded to an alkyl or aryl group. Radicals of R or Ri are not typically part of the stable ester structure but may be involved in the formation or reaction processes related to the ester. In some examples, R is a linear or branched alkyl group, and Ri is a linear orbranched alkyl group having less than or equal to 6 carbons. In some examples, R is a linear or branched alkyl group having 7 carbons, and Ri is a linear or branched alkyl group having less than or equal to 6 carbons. In some examples, R is a linear or branched alkyl group having 9 carbons, and Ri is a linear or branched alkyl group having less than or equal to 6 carbons. In some examples, R is a linear or branched alkyl group, and Ri is a linear or branched alkyl group having 5 carbons. In some examples, R is a linear or branched alkyl group having 7 carbons, and Ri is a linear or branched alkyl group having 5 carbons. In some examples, R is a linear or branched alkyl group having 9 carbons, and Ri is a linear or branched alkyl group having 5 carbons. In some examples, R is a linear or branched alkyl group of the formula -(CH2)n-CH3, where n is 6 to 12, and Ri is a branched alkyl group. In some examples, R is a linear or branched alkyl group of the formula -(CH2)n-CH3, where n is 6, 7, 11, and 12, and Ri is a branched alkyl group.

[0061] An acyl group R is a functional group derived from a carboxylic acid by removing the hydroxyl (-OH) group. The acyl group contributes to the overall structure and properties of the ester, influencing characteristics such as its melting point, viscosity, and skin feel. The specific acyl group used can affect the emollient properties of the resulting ester, including its spreadability and moisturizing efficacy when incorporated into personal care formulations. The alkyl group Ri may be derived from an alcohol or may be an alcohol residue. The specific structure of the alkyl group Ri influences properties such as the melting point, viscosity, and skin penetration characteristics of the resulting thermal protective agent. For example, a longer alkyl chain may increase the emollient properties of the thermal protective agent, while a branched chain may affect its spreadability on hair. The choice of alkyl radical length and structure in the thermal protective agent can be tailored to optimize the desired properties of the personal care formulation.

[0062] The isoamyl ester compounds used in the hair care compositions may be represented by Formula I: R1-COO-R2 In Formula I, R1 represents a fatty acid chain derived from various natural sources, while R2 represents an isoamyl group derived from isoamyl alcohol. The isoamyl group R2 may have the structure (CH3)2CHCH2CH2-, which is obtained from isoamyl alcohol. In some cases, the isoamyl alcohol used to produce the isoamyl esters may be obtained from sugar cane, a renewable source.

[0063] The fatty acid chain R1 may be derived from caprylic, capric, cocoate, palmitic, or stearic acids. These fatty acids may have carbon chain lengths of C8, CIO, Cl 2, Cl 6, or Cl 8, respectively. In some cases, the fatty acids used to produce the isoamyl esters may be derived from coconut or palm kernel, which are also renewable sources.

[0064] The isoamyl ester compounds may also be represented by the formula: CH3(CH2)nCOOCH2CH(CH3)2In this formula, n may be an integer from 6 to 16. In some cases, n may be selected from the group consisting of 6, 8, 10, 14, and 16. These different values of n correspond to different isoamyl ester compounds: When n = 6, the compound may be isoamyl caprylate (C8:0); When n = 8, the compound may be isoamyl caprate (C10:0); When n = 10-16, the compound may be isoamyl cocoate (mixture of fatty acids, mainly C12-C18); When n = 14, the compound may be isoamyl palmitate (Cl 6:0); and When n = 16, the compound may be isoamyl stearate (Cl 8:0).

[0065] The ester may have a formula R-COO-C5H11, wherein R is a linear or branched alkyl group of formula -(CH2)n-CH3 and n is a natural number. The ester may have a formula R-COO-C5H11, wherein R is a linear or branched alkyl group of formula -(CH2)n-CH3 and n is 6. The ester may have a formula R-COO-C5H11, wherein R is a linear or branched alkyl group of formula -(CH2)n-CH3and n is 8.

[0066] The ester may have a formula R-COO-CH2CH2CH(CH3)2, where R is a linear or branched alkyl group of formula -(CH2)n-CH3and n is a naturalnumber. In the context of the ester formula R-COO-CH2CH2CH(CH3)2, the acyl group is represented by R-C(=O)-, where R is the alkyl group derived from the fatty acid used in the esterification reaction. In some examples, the ester may have a formula R-COO-CH2CH2CH(CH3)2, where R is a linear or branched alkyl group of formula -(CH2)n-CH3 and n is 6 to 8. In some examples, the ester may have a formula CH3-(CH2)6-COO-CH2CH2CH(CH3)2. In some examples, the ester may be isoamyl octanoate (isoamyl caprylate). In some examples, the ester may have a formula CH3-(CH2)g-COO-CH2CH2CH(CH3)2. In some examples, the ester may be isoamyl decanoate (isoamyl caprate).

[0067] In the thermal protective agent described, the acyl group is derived from either octanoic (caprylic) acid or decanoic (capric) acid, depending on whether n is 6 or 8 in the formula -(CH2)n-CH3. In this case, the fatty acid is typically either octanoic (caprylic) acid when n is 6, or decanoic (capric) acid when n is 8. These medium-chain fatty acids are chosen for their specific properties that contribute to the emollient and moisturizing capabilities of the resulting ester. The choice of alkyl group length can affect various properties of the thermal protective agent, such as its melting point, viscosity, and skin penetration characteristics, which in turn influence the performance and feel of the personal care formulation.

[0068] The ester may have a formula R — COO — CH2CH2CH(RI)2R2where R is a linear or branched alkyl group of the formula -(CH2)n-CH3, with n between 1 to 12, Ri is independently, H, Ci-Cio alkyl, or a substituted alkyl group, and an R2is an unsubstituted linear or branched C1-C12 alkyl group. In some cases, the two Ri groups may be attached to the same carbon, forming a branched structure. In some cases, the total number of carbon atoms in the acyl portion (R-CO-) is 4 to 9. In some cases, the total number of carbon atoms in the acyl group is 8 carbons. In some cases, the total number of carbons in the acyl group is 10 carbons.

[0069] In some cases, R is a linear alkyl group of the formula -(CH2)n-CH3, with n between 2 and 7 (i.e., 3-8 carbons total for R) and / or, R i is independently, H or C1-C3 alkyl, and / or R2is an unsubstituted linear or branched Ci-Ce alkyl group. In some cases, the two Ri groups may be attached to the same carbon, forming a branched structure. In some cases, the total number of carbon atoms in the acyl portion (R-CO-) is 4 to 9.

[0070] In some cases, R is a linear alkyl group of the formula -(CH2)n-CH3, with n between 2 and 7 (i.e., 3-8 carbons total for R) and / or, Ri is independently, H or C1-C3 alkyl, and / or R2is an unsubstituted linear or branched Ci-Ce alkyl group. In some cases, the two Ri groups may be attached to the same carbon, forming a branched structure.

[0071] In some cases, R is a linear alkyl group of the formula -(CH2)n-CH3, with n between 1 and 12 (i.e., 2-13 carbons total for R) and / or, Ri is independently, H or Ci-C5 alkyl with two Ri groups attached to the same carbon, forming a branched structure and / or R2is an unsubstituted linear or branched Ci-Cs alkyl group.

[0072] In some cases, R is a linear alkyl group of the formula -(CH2)n-CH3, with n between 1 and 12 (i.e., 2-13 carbons total for R) and / or, Ri is independently, H or Ci-Cs alkyl with two Ri groups attached to the same carbon, forming a branched structure and / or R2is an unsubstituted linear or branched Ci-C10 alkyl group.

[0073] In some cases, Ri is a substituted alkyl group with a single substituent (e.g., methyl group, hydroxyl group, etc.). Alkyl groups are hydrocarbon chains derived from alkanes, typically represented as R or Ri, with structures like -CH3 (methyl), -CH2CH3 (ethyl), -CH2CH2CH3 (propyl), and so on. Substituted alkyl groups are alkyl groups that have one or more atoms or groups attached to the main carbon chain, which modifies the basic structure. Single substituent means that only one additional group or atom is attached to the main alkyl chain.

[0074] In some examples, the personal care formulation may include a mixture of a first thermal protective agent and a second thermal protective agent, which are different compounds. The different compounds may be based on different formula or same formula with different variables. In some examples, the personal care formulation may include a mixture of a first thermal protective agent and a second thermal protective agent in which each of the first thermal protective agent and the second thermal protective agent has a formula R-COO-CH2CH2CH(CH3)2, where R is a linear or branched alkyl group of formula -(CH2)n-CH3 and n is a natural number, and the first thermal protective agent has a different n than the second thermal protective agent. In some examples, the personal care formulation may include a mixture of a first thermal protective agent and a second thermal protective agent, where each of the first thermal protective agent and the second thermal protective agent having a formula R-COO-CH2CH2CH(CH3)2, R is a linear or branched alkyl group of formula -(CH2)n-CH3, and n is a natural number, and n is 6 for the first thermal protective agent and n is 8 for the second thermal protective agent.

[0075] In some aspects, the personal care formulation may include a thermal protective agent of formula R-COO-CH2CH2CH(CH3)2, where R is a linear or branched alkyl group of formula -(CH2)n-CH3. In this formula, n may be an integer from 6 to 8, indicating that the alkyl chain can vary in length from 7 to 9 carbon atoms in total. In some cases, n may be 6 or 8, corresponding to the use of octanoic (caprylic) acid or decanoic (capric) acid, respectively, in the synthesis of the thermal protective agent. The specific value of n may be selected based on various factors, such as the desired properties of the moisturizing agent, the available sources of fatty acids, and the specific requirements of the personal care formulation.

[0076] The isoamyl ester compounds may have properties that make them suitable alternatives to traditional hair care ingredients. These properties may include emollient characteristics that provide moisturizing and softening effectson hair, film-forming ability that may contribute to thermal protection properties, low viscosity resulting in a light, non-greasy feel desirable in hair care formulations, thermal stability that may contribute to effectiveness as thermal protectants, and biodegradability due to their derivation from renewable sources compared to some synthetic alternatives.

[0077] The use of these isoamyl ester compounds in hair care formulations may offer potential advantages in terms of sustainability and performance. Their derivation from renewable sources may align with growing consumer demand for natural and environmentally responsible personal care products. Additionally, their unique chemical structures may provide functional benefits in hair care applications, particularly in the context of thermal protection during heat styling processes.

[0078] The isoamyl ester compounds may provide thermal protection to hair through various mechanisms. In some cases, these compounds may form a protective film on the hair surface when applied prior to heat styling. This film may act as a barrier, helping to distribute heat more evenly across the hair shaft and reducing direct contact between the heating element and the hair fibers.

[0079] The film-forming properties of isoamyl esters may be attributed to their molecular structure. The fatty acid portion of the molecule may interact with the lipids present in the hair cuticle, while the isoamyl group may contribute to the compound’s ability to spread and form a uniform layer on the hair surface. This film may help to seal the cuticle, potentially reducing moisture loss during heat exposure.

[0080] In some cases, isoamyl esters may also interact with hair proteins, particularly keratin. These interactions may help to stabilize the protein structure, potentially reducing the risk of heat-induced protein denaturation. The ester linkage in the isoamyl ester compounds may form hydrogen bonds with amino acid residues in the keratin structure, which may contribute to the thermal protection effect.

[0081] In some embodiments, the thermal protective agent may be present in about 0.1% to about 5% by weight of the personal care formulation, such as 1% by weight. The specific concentration of the thermal protective agent in the formulation may be adjusted based on various factors, such as the desired moisturizing effect, the stability of the formulation, the sensory properties of the formulation, thermal protection properties, or other characteristics.

[0082] When compared to traditional thermal protectants like Bis-Cetearyl Amodimethicone and Hemisqualane, isoamyl esters may offer certain advantages. For example, isoamyl esters may have a lower molecular weight compared to Bis-Cetearyl Amodimethicone, which may allow for better penetration into the hair shaft. This deeper penetration may provide more comprehensive protection against heat damage. Isoamyl esters may perform similarly or superior to traditional thermal protectants with characteristic filmforming properties and low thermal conductivity, which may help reduce heat transfer from the source to the hair fiber, thereby minimizing water loss. Isoamyl esters may protect the hair’s keratin, an essential structural protein that keeps hair strong and healthy. By forming a protective barrier, these ingredients can reduce the direct impact of heat on keratin, preventing its degradation due to high temperatures and maintaining the hair’s integrity and strength.

[0083] In some embodiments, the personal care formulation may include one or more additives, such as solvent, thickener, film former, stabilizer, chelating agent, emollient, emulsifier, moisturizer, antioxidant, skin conditioning agent, preservative, pH adjuster, etc. The additive may include one or more or a mixture of the following: Cyclopentasiloxane, Dimethiconol, Ethylhexyl Methoxycinnamate, Simmondsia Chinensis Seed Oil. The one or more additive may be at least 0.1 wt%, such as 0.2wt%, 0.5wt%, lwt%, etc. of the personal care formulation.

[0084] A cosmetically acceptable vehicle is an essential component of a cosmetic or hair product that stabilizes and helps maintain the stability of activeingredients, preventing degradation or separation of the product. The vehicle enhances application by improving the texture, spreadability, and absorption of the product on the skin or hair. A suitable vehicle should be non-irritating, safe, non-toxic, non-sensitizing, and suitable for regular use on the skin or hair, while also being compatible with and not interfering with the efficacy of the active ingredients in the formulation.

[0085] Common examples of cosmetically acceptable vehicles include water (aqua), oils, emulsifiers, silicones, and certain polymers, which support the product’s overall function and feel while carrying the active components to the target area.

[0086] In some embodiments, the personal care formulation may further comprise a thickener and an emulsifier, each present in at least 0.1% by weight of the personal care formulation. The thickener may serve to increase the viscosity of the formulation, improving its texture and spreadability. The emulsifier may help to stabilize the formulation, preventing the separation of its components and ensuring a uniform distribution of the moisturizing agent and the additional moisturizing agent throughout the formulation.

[0087] In some cases, the hair care composition may further include a silicone compound. The combination of isoamyl esters with silicone compounds may provide synergistic thermal protection effects. Silicone compounds may enhance the film-forming properties of the composition, potentially improving its ability to shield the hair from heat damage.

[0088] The hair care composition may be configured to be applied to hair prior to using a heat styling device to provide thermal protection. This pre-treatment approach may allow the protective compounds to distribute evenly throughout the hair and form a protective barrier before exposure to high temperatures.

[0089] In some cases, the silicone compound may be selected from dimethicone, cyclomethicone, and amodimethicone. These silicone compounds may have different properties that complement the thermal protection providedby isoamyl esters. For example: 1. Dimethicone may form a flexible, breathable film on the hair surface, which may enhance the protective barrier created by isoamyl esters; 2. Cyclomethicone may have a low molecular weight, allowing for quick evaporation after application. This property may help to distribute the isoamyl esters more evenly throughout the hair; and 3. Amodimethicone may have a positive charge, which may allow it to adhere more effectively to negatively charged hair surfaces. This improved adhesion may enhance the overall thermal protection of the composition.

[0090] The combination of isoamyl esters with these silicone compounds may result in a hair care composition that provides comprehensive thermal protection.The isoamyl esters may interact with hair proteins and form a protective film, while the silicone compounds may enhance the film-forming properties and provide additional heat-resistant characteristics. This multi-faceted approach to thermal protection may help to preserve hair health and appearance during heat styling processes.

[0091] Table 1 shows a molecular comparison of film-forming components.> "Table 1.

[0092] Bis-Cetearyl Amodimethicone is a modified silicone with long alkyl chains (Cl 6 / C 18) and -Si-O-Si- bonds. Such silicones may have film- formingproperties due to their flexible and hydrophobic structure, which helps form a protective barrier on the surface.

[0093] Hemisqualane is a long-chain hydrocarbon (Cl 2), similar to squalane. This hydrocarbon is linear, lipophilic structure that can promote good spreadability and the formation of a light film.

[0094] Isoamyl Caprylate / Caprate is a short-chain ester (C8 / C10). This ester can promote smoothness and spreadability, offering a light film formation.

[0095] Isoamyl Cocoate is medium-chain ester (C12). This ester has a structure that is conducive to providing film-forming properties with good spreadability and moisturizing effect.

[0096] Isoamyl Palmitate / Stearate has longer chains (Cl 6 / C 18), which can contribute to greater film formation and a more velvety feel.

[0097] Physical and chemical analyses may be used to measure the thermal protection properties. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) are thermoanalytical techniques applied in the development of various studies involving a broad range of cosmetics and pharmaceutical materials.

[0098] TGA provides information on mass changes as a function of time and / or temperature under a specific atmosphere. The resulting curves offer insights into the composition and thermal stability of the sample, intermediate products, and the residue formed.

[0099] DSC is a thermal analysis technique that measures the energy difference supplied to a substance and a thermally stable reference material as a function of temperature, while both are subjected to a controlled temperature program.

[0100] Another analysis is microscopy, on a micrometric scale, which shows how the film is formed on the hair fiber. Microscopy allows the visualization of the cuticles, where you can see if the thermal protection was effective after the heat application.

[0101] A material having a high decomposition temperature does not mean that it will have effective thermal protection, because the homogeneity of the film formed on the hair fiber is important for thermal protection to take place. Therefore, TGA analysis, DSC analysis, and microscopy complement each other when interpreting the results.

[0102] The following steps were used to develop thermal hair protectants: molecule synthesis, TGA analysis of pure raw materials, and formulation of thermal protection oil.

[0103] Example 1: Molecule Synthesis

[0104] The synthesis of isoamyl ester compounds (e.g., emollient) may be carried out (e.g., on an industrial scale) using esterification reactions between isoamyl alcohol and various acids (e.g., fatty acids). The general reaction for the synthesis of these compounds may be represented by the following equation: Rl-COO-R2. In this reaction, R1 represents the fatty acid chain, which may vary depending on the specific isoamyl ester being synthesized. R2 represents the isoamyl group derived from isoamyl alcohol, having the structure (CH3)2CHCH2CH2-.

[0105] The synthesis process may be optimized to minimize loss and waste generation, potentially improving the overall efficiency and sustainability of the production. In some cases, this optimization may involve careful control of reaction conditions, efficient separation and purification techniques, and recycling of unreacted starting materials.

[0106] The materials used to carry out the synthesis includes:Isoamyl Alcohol + C8 (Caprylic) Acid and CIO (Capryc) Acid Isoamyl Alcohol + C12 (Coconut) AcidIsoamyl Alcohol + C16 (Palmitic) Acid and C18 (Stearic) Acid

[0107] For the synthesis of Isoamyl Caprylate / Caprate, the following reaction may occur:(CH3)2CHCH2CH2OH + CH3(CH2)6COOH CH3(CH2)6COOCH2CH2CH(CH3)2+ H2OIn this reaction, isoamyl alcohol reacts with caprylic acid (C8) to form isoamyl caprylate. A similar reaction may occur with capric acid (CIO) to form isoamyl caprate.

[0108] For the synthesis of Isoamyl Cocoate, the reaction may involve a mixture of fatty acids derived from coconut oil, primarily lauric acid (Cl 2): (CH3)2CHCH2CH2OH + CH3(CH2)WCOOH CH3(CH2)IOCOOCH2CH2CH(CH3)2+ H2O

[0109] The synthesis of Isoamyl Palmitate / S tearate may involve reactions with palmitic acid (C16) and stearic acid (C18):(CH3)2CHCH2CH2OH + CH3(CH2)MCOOH CH3(CH2)14COOCH2CH2CH(CH3)2+ H2O(CH3)2CHCH2CH2OH + CH3(CH2)16COOH CH3(CH2)16COOCH2CH2CH(CH3)2+ H2O

[0110] These esterification reactions, which were carried out on an industrial scale, are summarized in Table 2.Table 2>> >

[0111] In some cases, the synthesis process may involve the following steps: 1. Charging of reactants: Isoamyl alcohol and the appropriate fatty acid may be added to a reactor vessel; 2. Catalyst addition: An acid catalyst, such as sulfuric acid or p-toluenesulfonic acid, may be added to promote the esterification reaction; 3. Heating: The reaction mixture may be heated to a temperature between 120°C and 180°C to drive the esterification reaction; 4. Water removal: The water produced as a byproduct of the reaction may be continuously removed to drive the equilibrium towards product formation. This may be achieved through azeotropic distillation or the use of molecular sieves; 5. Reaction monitoring: The progress of the reaction may be monitored by measuring the acid value of the reaction mixture; 6. Purification: Once the reaction is complete, the crude product may be purified through processes such as distillation, neutralization, and filtration; and 7. Quality control: The final product may be analyzed to ensure it meets the desired specifications, including purity, acid value, and saponification value.

[0112] The industrial-scale production of these isoamyl ester compounds may be carried out in batch or continuous processes, depending on the specific requirements and scale of production. In some cases, the production process may be designed to allow for the synthesis of multiple isoamyl ester variants using the same equipment, with appropriate cleaning and changeover procedures between batches.

[0113] Table 3 summarizes the properties of the products obtained by the esterification process.Table 3<

[0114] Example 2: TGA Analysis of Pure Raw Materials

[0115] Thermogravimetric analysis (TGA) may be used to evaluate the thermal stability and decomposition behavior of the isoamyl esters and comparative compounds, which were listed in Table 1. In some cases, TGA curves may provide information on mass changes as a function of temperature under a specific atmosphere.

[0116] FIG. 5 and FIG. 6 show thermogravimetric curves for Bis-Cetearyl Amodimethicone and Hemisqualane, respectively. The TGA curve for Bis-Cetearyl Amodimethicone in FIG. 5 may exhibit a complex decomposition pattern with multiple events, suggesting a mixture of components. The onset of significant mass loss for Bis-Cetearyl Amodimethicone may occur at a higher temperature compared to the other compounds analyzed.

[0117] FIG. 7 and FIG. 8 present the TGA curves for Isoamyl Caprylate / Caprate and Isoamyl Cocoate, respectively. These curves may show a single, sharp transition indicating the thermal decomposition of the compounds. The onset temperature and rate of decomposition may vary between the two isoamyl esters, potentially reflecting differences in their molecular structures and chain lengths.

[0118] FIG. 9 depicts the TGA curve for Isoamyl Palmitate / S tearate. This curve may also demonstrate a single thermal event, with the decomposition occurring over a specific temperature range.

[0119] Table 4 shows the TGA results of the film-forming molecules listed in Table 1.Table 4

[0120] In some cases, the TGA results may be summarized as follows: 1. Bis- Cetearyl Amodimethicone may exhibit thermal stability up to approximately 337°C, with decomposition occurring over a broad temperature range up to about 634°C; 2. Hemisqualane may begin to decompose at a lower temperature, with the onset of mass loss occurring around 26°C and continuing up to about 186°C; 3. Isoamyl Caprylate / Caprate may show thermal stability up to about 26°C, with decomposition occurring between 26°C and 206°C; 4. Isoamyl Cocoate may demonstrate thermal stability up to approximately 25 °C, with decomposition taking place between 25°C and 280°C; 5. Isoamyl Palmitate / S tearate may exhibit thermal stability up to about 26°C, with decomposition occurring between 26°C and 352°C.

[0121] The TGA curves suggest that the size of the chains / molecular weight is related to the decomposition of the material as a function of temperature. In other words, the TGA analysis indicates that the thermal stability of the isoamyl esters may be related to their molecular weight and chain length. In some cases, compounds with longer carbon chains, such as Isoamyl Palmitate / Stearate, may exhibit higher decomposition end temperatures compared to those with shorter chains, like Isoamyl Caprylate / Caprate. Bis-cetearyl amodimethicone, shown in Figure 5, showed a different behavior to the others, with different events that suggest a mixture of components.

[0122] The thermal stability of these compounds may be relevant to their performance as thermal protectants in hair care formulations. Compounds with higher decomposition temperatures may potentially provide more effectiveprotection against heat damage during styling processes that involve high temperatures.

[0123] In some cases, the TGA results may be used to inform the selection of appropriate isoamyl esters for specific hair care applications. For example, formulations intended for use with high-heat styling tools may benefit from incorporating isoamyl esters with higher thermal stability.

[0124] Further analyses may help that the film formation for thermal protection was effective. To this end, different heat protectant formulas were formulated, varying only the film- forming agent, to be applied to the hair strands and then analyzed by microscopy and DSC.

[0125] Example 3: Formulation of Thermal Protection Oil

[0126] In some cases, thermal protection oils may be formulated using different film-forming agents. These formulations may include a base composition with various ingredients, to which specific film-forming agents may be added. Formulations of thermal protection oil were applied, in which the base of the formulation is the same and only the film-forming agent has been changed. Table 5 shows thermal protector formulations.Table 5

[0127] The film-forming agent may be one of the following: 1. Bis-Cetearyl Amodimethicone; 2. Hemisqualane; 3. Isoamyl Caprylate / Caprate; 4. Isoamyl Cocoate; and 5. Isoamyl Palmitate / S tearate.

[0128] In some cases, the preparation process for these thermal protection oil formulations may involve the following steps: 1. Addition of cyclopentasiloxane to a mixing vessel; 2. Incorporation of dimethiconol into the cyclopentasiloxane with gentle stirring; 3. Addition of ethylhexyl methoxycinnamate to the mixture; 4. Incorporation of Simmondsia Chinensis seed oil; 5. Addition of the selected film-forming agent (1.0% by weight); and 6. Gentle mixing of all components until a homogeneous formulation is achieved. The ingredients were homogenized according to the order of addition.

[0129] In some cases, the thermal protection oil formulations may be applied to hair strands prior to heat styling. The application amount may be approximately 0.4 grams of the formulation per hair strand. This amount may provide sufficient coverage to form a protective film on the hair surface.

[0130] The incorporation of isoamyl ester compounds (Isoamyl Caprylate / Caprate, Isoamyl Cocoate, or Isoamyl Palmitate / Stearate) as filmforming agents in these formulations may provide thermal protection properties to the hair. These compounds may interact with the hair surface and potentially form a protective barrier against heat damage during styling processes.

[0131] The results of testing the film-forming agent involved standardization of hair strands to Microscopy (With Flat Iron), Microscopy analysis of treated hair strands, Standardization of hair strands to DSC (Without Flat Iron), and DSC analysis of treated hair strands

[0132] Example 4 Microscopy

[0133] In some cases, optical microscopy may be used to evaluate the effect of isoamyl esters on hair cuticles after heat application. FIG. 10A-10G shows optical microscopy images of hair strands at a scale of 20 micrometers, displaying the surface characteristics and cuticle patterns after different treatments.

[0134] The microscopy analysis may involve the following steps: 1. Preparation of hair strands: International Hair Caucasian Type 2 virgin hair strands may be washed in a 20 percent sodium lauryl ether sulphate solution; 2. Application of formulations: After drying, different strands may be separated and 0.4 grams of various formulations as shown in Table 5 may be applied to each strand; 3. Heat application: A flat iron at 250°C may be applied to the entire strand for evaluation under optical microscopy; and 4. Microscopy analysis: The hair strands may be observed under optical microscopy using an Olympus BX51 microscope at a scale of 20 micrometers.

[0135] The conditions for assessing and drying the strands may be maintained at 25°C ± 2°C and 60% humidity ± 5%.

[0136] FIGS. 10A-10G show optical microscopy of hair strands after flat ironing.

[0137] FIG. 10A shows a reference hair strand without any treatment, displaying the natural cuticle pattern and surface texture of untreated hair.

[0138] FIG. 10B presents a hair strand treated with a base formulation without any film-forming agent. In some cases, changes in the cuticle pattern may be observed, potentially indicating some level of heat-induced damage.

[0139] FIG. 10C depicts a hair strand treated with a base formulation containing Bis-Cetearyl Amodimethicone. The image may show a distinctive film formation on the hair surface, which may be characteristic of silicone -based treatments.

[0140] FIG. 10D illustrates a hair strand treated with a Hemisqualane-containing formulation. In some cases, alterations in the cuticle structure may be visible, potentially suggesting limited thermal protection.

[0141] FIG. 10E shows a hair strand treated with Isoamyl Caprylate / Caprate formulation. The surface characteristics after heat application may indicate some level of thermal protection.

[0142] FIG. 10F presents a hair strand treated with Isoamyl Cocoate formulation. The effects on the hair surface and cuticle pattern may demonstrate the thermal protection properties of this isoamyl ester.

[0143] FIG. 10G depicts a hair strand treated with Isoamyl Palmitate / S tearate formulation. The resulting surface characteristics following treatment and heat application may provide insights into the thermal protection efficacy of this compound.

[0144] In some cases, the microscopy analysis may reveal that the strands treated with the isoamyl ester formulations (FIG. 10E, FIG. 10F, and FIG. 10G) may appear to have maintained a more natural and healthy appearance compared to the untreated strand (FIG. 10A) or the strand treated with the base formulation without a film-forming agent (FIG. 10B).

[0145] The strand treated with hemisqualane (FIG. 10D) or treated with a base without a film-forming agent (FIG. 10B) may show signs of cuticle damage, potentially indicating lower thermal protection efficacy. In contrast, the strand treated with Bis-Cetearyl Amodimethicone (FIG. 10C) may exhibit a visible film formation on the hair fiber, which may be characteristic of silicone-based treatments.

[0146] These microscopy observations may provide visual evidence of how different film-forming agents affect the hair surface structure and cuticle pattern when exposed to heat treatment. The analysis may suggest that isoamyl ester compounds may offer effective thermal protection, potentially preserving the natural appearance and health of hair strands during heat styling processes.

[0147] Example 5: DSC Analysis of Treated Hair Strands

[0148] Differential scanning calorimetry (DSC) may be used to evaluate the thermal protection properties of the isoamyl esters and comparative compounds.In some cases, DSC analysis may provide information on thermal events and transitions occurring in the treated hair strands when exposed to increasing temperatures. Hair strands were standardized for DSC similar to Example 4 except that the hair strands were not subjected to a flat iron.

[0149] The DSC analysis may be conducted under the following conditions: 1. Nitrogen gas atmosphere at a flow rate of 50 mL / min; 2. Heating rate of 10°C / min; 3. Temperature range of 25 to 400°C; and 4. Sealed aluminum crucible containing approximately 3.0 mg of sample.

[0150] The DSC thermograms may be evaluated in terms of the intensity of the signal emitted in AH ( J / g). In some cases, the analysis may focus on two main events: 1. Hydration degradation: This event may take place around 40-185°C. A higher signal in this region may indicate greater hydration protection attributed to the sample; and 2. Alpha-keratin degradation: This event may occur around 225-250°C. A higher signal modulus in this region may suggest greater alphakeratin protection attributed to the sample.

[0151] The untreated hair strand was not analyzed because the wick burned in the crucible, thereby preventing analysis.

[0152] FIG. 11 and FIG. 12 present DSC thermograms for hair strands treated with different formulations. FIG. 11 may show the DSC curve for a hair strand treated with a base formulation without a film-forming agent. The thermogram may display a prominent negative peak in the red shaded region, potentially corresponding to the hydration degradation event. Additional smaller peaks shown in orange and pink shaded areas may represent alpha-keratin degradation events.

[0153] FIG. 12 may depict the DSC thermogram for a hair strand treated with a formulation containing Bis-Cetearyl Amodimethicone. The curve may show a broad negative peak in the red shaded region, which may indicate the hydration degradation event. The thermogram may also display additional smaller peaks inorange and pink shaded areas, potentially representing alpha-keratin degradation events.

[0154] FIG. 13 and FIG. 14 present DSC thermograms for hair strands treated with formulations containing Hemisqualane and Isoamyl Caprylate / Caprate, respectively. In FIG. 13, the thermogram may show a curve with multiple thermal events, including a significant thermal transition in the red shaded region. FIG.14 may display a similar pattern, with distinct peaks and transitions marked by colored indicators.

[0155] FIG. 15 and FIG. 16 depict DSC thermograms for hair strands treated with formulations containing Isoamyl Cocoate and Isoamyl Palmitate / S tearate, respectively. Both thermograms may show curves with multiple thermal events across the temperature range, including prominent negative peaks in the middle region.

[0156] FIG. 17 and FIG. 18 present additional DSC thermograms for hair strands treated with isoamyl cocoate and isoamyl caprylate / caprate, respectively. In FIG. 17, the thermogram may display multiple endothermic peaks, with a first thermal event shown in pink shading occurring in the lower temperature range corresponding to the hydration degradation event. Additional thermal events shown in orange and purple shading may appear at higher temperatures, representing alpha-keratin degradation events. FIG. 18 may exhibit a similar pattern, with distinct thermal transitions across the temperature range from approximately 40°C to 380°C.

[0157] FIG. 19 and FIG. 20 depict DSC thermograms for hair strands treated with isoamyl palmitate / stearate and hemisqualane, respectively. In FIG. 19, the thermogram may show a large endothermic peak in the red shaded region at lower temperatures corresponding to the hydration event, followed by orange and pink shaded peaks at higher temperatures corresponding to alpha-keratin degradation events. FIG.20 may display a similar thermal profile for the hemisqualane-treated hair strand, with a red shaded peak in the lower temperature region and orangeand pink shaded peaks at higher temperatures representing the keratin degradation events.

[0158] FIG. 21 and FIG. 22 present DSC thermograms for hair strands treated with cyclomethicone and bis-cetearyl amodimethicone, respectively. Both thermograms may exhibit multiple thermal events across the temperature range from approximately 40°C to 360°C. In each thermogram, a first thermal event shown in magenta shading may occur between approximately 40°C and 185 °C, corresponding to the removal and evaporation of bound water in the hair fiber. Second and third thermal events shown in orange and purple shading may occur in the higher temperature range between approximately 220°C and 280°C, corresponding to the degradation of alpha-keratin.

[0159] FIG. 23 and FIG. 24 depict DSC thermograms for hair strands treated with coconut oil and mineral oil, respectively. Both thermograms may contain multiple shaded regions indicating thermal events, including a large shaded region in the lower temperature range corresponding to the hydration degradation event and additional smaller shaded regions at higher temperatures corresponding to alpha-keratin degradation events. In some cases, the hair strand treated with coconut oil in FIG. 23 may exhibit different thermal behavior compared to the hair strand treated with mineral oil in FIG. 24, potentially reflecting differences in the protective capabilities of these two emollients against thermal damage.

[0160] FIG. 25 presents a DSC thermogram for a hair strand treated with diisoamyl succinate. The thermogram may show three distinct endothermic peaks represented by shaded regions. A first peak may appear in the lower temperature range between approximately 40°C and 185 °C, shown with red diagonal hatching, corresponding to the hydration event related to water removal from the hair fiber. A second peak may appear in the mid-temperature range around 230°C, shown with orange shading, representing a first alpha-keratin degradation event. A third peak may appear at a slightly higher temperature around 265 °C, shown with pink shading, representing a second alpha-keratin degradation event. Theenthalpy values associated with each thermal event may indicate the energy required to degrade the material at each stage.

[0161] In some cases, the DSC results may be interpreted as follows: 1.Hydration protection: The energy required to break down water in the hair strand may be indicated by the magnitude of the negative peak in the 40-185°C range.A larger negative AH value in this region may suggest better hydration protection; and 2. Alpha-keratin protection: The energy associated with the degradation of alpha-keratin may be represented by the peaks in the 225-250°C range. A larger negative AH value in this region may indicate better protection of the hair’s protein structure.

[0162] Table 6 summarizes the DSC results.Table 6properties among the various formulations. In some cases, isoamyl ester compounds may demonstrate improved hydration protection and alpha-keratin stability compared to the base formulation without a film-forming agent. The specific performance of each isoamyl ester (Isoamyl Caprylate / Caprate, IsoamylCocoate, and Isoamyl Palmitate / Stearate) may vary, potentially reflecting differences in their molecular structures and interactions with hair proteins.

[0164] The results in table 6 show the results for moisturizing protection and alpha-keratin protection, and the negative AH (J / g) sign indicates the energy expended to degrade the material.

[0165] In terms of hydration protection, Isoamyl Cocoate and Isoamyl Palmitate / Stearate had better results, because the energy used to break down the water was higher. Isoamyl Caprylate / Caprate had very similar results to Bis-Cetearyl Amodimethicone. Hemisqualane, on the other hand, had lower results than the White formulation, without the film-forming agent, indicating that this material has low hydration protection.

[0166] In terms of alpha-keratin protection, Isoamyl Palmitate / Stearate and Bis-Cetearyl Amodimethicone had equal results, and Isoamyl Cocoate had even better results. On the other hand, Isoamyl Caprylate / Caprate and Hemisqualane had inferior results very close to the White formula, without a film-forming agent, indicating that they have low alpha-keratin protection.

[0167] The DSC results may provide quantitative support for the thermal protection properties of isoamyl ester compounds in hair care formulations. This analysis, combined with other experimental data, may contribute to the understanding of how these compounds interact with hair fibers and provide protection against heat-induced damage during styling processes.

[0168] Among the film- forming agents evaluated, hemisqualane had the worst results in all aspects.

[0169] According to the results obtained in the study, we can conclude that Isoamyl Caprylate / Caprate and Bis-Cetearyl Amodimethicone showed very close results in terms of protection against hydration, but Isoamyl Palmitate / Stearate and Isoamyl Cocoate showed superior results.

[0170] Bis-Cetearyl Amodimethicone, Isoamyl Palmitate / Stearate and Isoamyl Cocoate showed better results in protecting alpha-keratin.

[0171] Bearing in mind that the thermal protection benchmark is Bis-Cetearyl Amodimethicone, we can conclude that: Isoamyl Caprylate / Caprate provides effective thermal protection against hair dehydration; Isoamyl Cocoate provides effective thermal protection against dehydration and alpha-keratin degradation of the hair; and Isoamyl Palmitate / S tearate provides effective thermal protection against dehydration and alpha-keratin degradation of the hair. The results highlight the unique benefits of each product, emphasizing its superior performance in protecting hydration and alpha-keratin of the hair compared toother film-forming agents.

[0172] Table 7 below illustrate results for the thermal protection capacity of each emollient described above in reference to FIGS 17 through 25.Table 7.

[0173] The results in Table 7 show that the Isoamyl esters performed better than any other emollient tested. It is noted that in terms of protection against the degradation of alpha keratin, Diisoamyl Succinate was the one that had the best performance. As it is a diester, it is expected that the permeation in the hair cuticle will be more efficient, collaborating for greater protection of alpha keratin. This behavior is also expected for permeation on the skin.

[0174] In some cases, the combination of various components in the hair care composition may provide synergistic effects for thermal protection. The isoamylester compounds, represented by the formula CH3(CH2)nCOOCH2CH(CH3)2, where n ranges from 6 to 16, may work in conjunction with other ingredients to create a comprehensive thermal protection system for hair.

[0175] The isoamyl ester compounds may include isoamyl caprylate (n=6), isoamyl caprate (n=8), isoamyl cocoate (n=10-16), isoamyl palmitate (n=14), and isoamyl stearate (n=16). Each of these compounds may contribute unique properties to the hair care composition, potentially enhancing its overall performance as a thermal protectant.

[0176] In some cases, the isoamyl ester compounds may form a protective film on the hair surface. This film may act as a barrier against heat, potentially reducing the direct impact of high temperatures on the hair shaft. The filmforming properties may vary depending on the specific isoamyl ester used in the composition.

[0177] The molecular structure of isoamyl esters may allow for better penetration into the hair shaft compared to some traditional thermal protectants. This enhanced penetration may result in more comprehensive protection against heat-induced damage. For example, isoamyl caprylate and isoamyl caprate, with their shorter chain lengths, may penetrate more easily into the hair structure.

[0178] In some cases, the longer chain isoamyl esters, such as isoamyl palmitate and isoamyl stearate, may provide additional conditioning benefits to the hair. These compounds may help to smooth the cuticle and reduce friction between hair strands, potentially minimizing heat-induced mechanical damage during styling processes.

[0179] The isoamyl ester compounds may also contribute to the overall sensory properties of the hair care composition. In some cases, these compounds may impart a light, non-greasy feel to the hair, which may be desirable for consumers. The specific physical properties of the isoamyl esters, including their appearance, color, odor, and viscosity, may influence the user experience and product performance.

[0180] When incorporated into a hair styling system comprising a heat styling device and a hair care composition, the isoamyl ester compounds may provide effective thermal protection. The composition may be applied to the hair prior to using heat styling tools, potentially creating a protective barrier against high temperatures.

[0181] In some cases, the isoamyl ester compounds may exhibit thermal stability at temperatures commonly used in heat styling processes. This stability may contribute to their effectiveness as thermal protectants, as they may maintain their protective properties even when exposed to high heat.

[0182] The combination of different isoamyl esters in a single formulation may provide a balance of properties. For example, a composition containing both isoamyl caprylate / caprate and isoamyl palmitate / stearate may offer a combination of easy penetration and enhanced conditioning effects.

[0183] In some cases, the isoamyl ester compounds may work synergistically with other ingredients in the hair care composition. For instance, the combination of isoamyl esters with silicone -based ingredients may result in enhanced film formation and improved heat distribution across the hair surface.

[0184] The physical properties of isoamyl esters, such as their low water content and specific refractive index, may contribute to their performance as thermal protectants. These properties may influence how the compounds interact with hair fibers and respond to heat exposure.

[0185] In some cases, the biodegradability of isoamyl esters may provide an environmental advantage over some traditional thermal protectants. This characteristic may align with growing consumer demand for more sustainable hair care products.

[0186] The isoamyl ester compounds may also contribute to the overall stability and shelf-life of the hair care composition. Their specific acid values and saponification values may influence the product’s resistance to degradation over time.

[0187] In some cases, the solubility properties of isoamyl esters may affect how the compounds are distributed throughout the hair care composition and how they interact with other ingredients. This may influence the overall performance and consistency of the product.

[0188] The pour point and flash point of the isoamyl esters may be relevant for product formulation and safety considerations. These properties may influence how the compounds behave during manufacturing, storage, and application processes.

[0189] In some cases, the molecular weight of the isoamyl esters may affect their ability to form a protective film on the hair surface. Compounds with different molecular weights may exhibit varying degrees of substantivity to the hair, potentially influencing their thermal protection efficacy.

[0190] The combination of these factors may contribute to the overall performance of hair care compositions containing isoamyl ester compounds as thermal protectants. The synergistic effects of various ingredients, coupled with the unique properties of isoamyl esters, may result in effective protection against heat-induced damage during styling processes.

[0191] Isoamyl Caprylate / Caprate, Isoamyl Cocoate, and Isoamyl Palmitate / Stearate are renewable ester-based ingredients demonstrating that they can be effective alternatives in hair care formulations, particularly as thermal protectors. These natural ingredients possess unique properties that make them promising substitutes for widely used compounds such as Bis-Cetearyl Amodimethicone and Hemisqualane.

[0192] Isoamyl Caprylate / Caprate, Isoamyl Cocoate, and Isoamyl Palmitate / Stearate offer a natural and effective solution by forming a protective barrier around the hair fiber, minimizing moisture loss and shielding the cuticle from heat damage.

[0193] In addition to their thermal protection capabilities, Isoamyl Caprylate / Caprate, Isoamyl Cocoate, and Isoamyl Palmitate / Stearate contributeto overall hair health by replenishing the lipid layer of the hair cuticle. This lipid layer plays a crucial role in maintaining the hair’s strength, elasticity, and resistance to external aggressors.

[0194] These isoamyl-based ingredients stand out as innovative solutions in hair care that can replace traditional compounds like Bis-Cetearyl Amodimethicone, known for its buildup potential, and Hemisqualane, a hydrocarbon with biodegradability challenges. Their ability to combine high performance with sustainability makes them a valuable addition to modern hair care formulations focused on providing effective heat protection while promoting environmental responsibility.

[0195] By incorporating these esters into hair care products, formulators can deliver solutions that cater to the growing consumer demand for safer, more natural, and eco-conscious alternatives without compromising on efficacy.

[0196] The following clauses illustrate example subject matter described herein.

[0197] Clause 1. A hair care composition comprising: an isoamyl ester compound of Formula I: R1-COO-R2, wherein R1 represents an acid-derived chain and R2 represents the isoamyl group derived from isoamyl alcohol, having the structure (CHihCHCfTCfT-; and a cosmetically acceptable carrier, wherein the composition provides thermal protection to hair fibers.

[0198] Clause 2. The hair care composition of Clause 1, wherein R1 is derived from a fatty acid selected from the group consisting of caprylic acid, capric acid, cocoate acid, palmitic acid, and stearic acid, having carbon chain lengths of C8, CIO, C12, C16, or C18 respectively.

[0199] Clause 3. The hair care composition of any one of Clauses 1-2, wherein R1 is derived from caprylic acid and has a carbon chain length of C8.

[0200] Clause 4. The hair care composition of any one of Clauses 1-2, wherein R1 is derived from capric acid and has a carbon chain length of CIO.

[0201] Clause 5. The hair care composition of any one of Clauses 1-2, wherein R1 is derived from cocoate acid and has a carbon chain length of Cl 2.

[0202] Clause 6. The hair care composition of any one of Clauses 1-2, wherein R1 is derived from palmitic acid and has a carbon chain length of Cl 6.

[0203] Clause 7. The hair care composition of any one of Clauses 1-2, wherein R1 is derived from stearic acid and has a carbon chain length of C18.

[0204] Clause 8. The hair care composition of Clause 1, wherein R1 is derived from succinic acid and the isoamyl ester compound is diisoamyl succinate.

[0205] Clause 9. The hair care composition of any one of Clauses 1-8, wherein the composition further comprises a silicone compound.

[0206] Clause 10. A hair care composition comprising: a mixture of a first thermal protective agent and a second thermal protective agent, the first thermal protective agent and the second thermal protective agent each being an isoamyl ester compound, wherein the first thermal protective agent is different from the second thermal protective agent, and wherein at least one of the first thermal protective agent and the second thermal protective agent is selected from the group consisting of isoamyl caprylate, isoamyl caprate, isoamyl cocoate, isoamyl palmitate, isoamyl stearate, and diisoamyl succinate.

[0207] Clause 11. The hair care composition of Clause 10, wherein the first thermal protective agent and the second thermal protective agent each have a formula CH3(CH2)nCOOCH2CH(CH3)2, wherein n is an integer from 6 to 16.

[0208] Clause 12. The hair care composition of any one of Clauses 10-11, wherein n is selected from the group consisting of 6, 8, 10, 14, and 16.

[0209] Clause 13. The hair care composition of any one of Clauses 10-12, wherein at least one of the first thermal protective agent and the second thermal protective agent is diisoamyl succinate.

[0210] Clause 14. A method for protecting hair from thermal damage, comprising:

[0211] applying to hair a composition comprising an isoamyl ester compound selected from the group consisting of isoamyl caprylate, isoamyl caprate, isoamyl cocoate, isoamyl palmitate, isoamyl stearate, and diisoamyl succinate; and

[0212] exposing the hair to heat from a heat styling device.

[0213] Clause 15. The method of Clause 14, wherein the isoamyl ester compound is isoamyl caprylate.

[0214] Clause 16. The method of Clause 14, wherein the isoamyl ester compound is isoamyl caprate.

[0215] Clause 17. The method of Clause 14, wherein the isoamyl ester compound is isoamyl palmitate.

[0216] Clause 18. The method of Clause 14, wherein the isoamyl ester compound is isoamyl stearate.

[0217] Clause 19. The method of Clause 14, wherein the isoamyl ester compound is diisoamyl succinate.

[0218] Clause 20. The method of any one of Clauses 14-19, wherein the composition further comprises a silicone compound selected from the group consisting of dimethicone, cyclomethicone, and amodimethicone.

[0219] While the disclosure has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the disclosure is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as permitted under the law. Furthermore, it should be understood that while the use of the word preferable, preferably, or preferred in the description above indicates that feature so described may be more desirable, it nonetheless may not be necessary and any embodiment lacking the same may be contemplated as within the scope of the disclosure, that scope being defined by the claims that follow. In reading theclaims it is intended that when words such as “a,” “an,” “at least one” and “at least a portion” are used, there is no intention to limit the claim to only one item unless specifically stated to the contrary in the claim. Further, when the language “at least a portion” and / or “a portion” is used the item may include a portion and / or the entire item unless specifically stated to the contrary.

Claims

CLAIMSWhat is claimed is:

1. A hair care composition comprising:an isoamyl ester compound of Formula I: R1-COO-R2, wherein R1 represents a fatty acid chain derived from caprylic, capric, cocoate, palmitic, or stearic acids, having carbon chain lengths of C8, CIO, C12, C16, or C18 respectively, and R2 represents the isoamyl group derived from isoamyl alcohol, having the structure (CfLhCHCfLCfL-: anda cosmetically acceptable carrier,wherein the composition provides thermal protection to hair fibers.

2. The hair care composition of claim 1, wherein R1 is derived from caprylic acid and has a carbon chain length of C8.

3. The hair care composition of claim 1, wherein R1 is derived from capric acid and has a carbon chain length of CIO.

4. The hair care composition of claim 1, wherein R1 is derived from cocoate acid and has a carbon chain length of Cl 2.

5. The hair care composition of claim 1, wherein R1 is derived from palmitic acid and has a carbon chain length of C16.

6. The hair care composition of claim 1, wherein R1 is derived from stearic acid and has a carbon chain length of Cl 8.

7. A hair care composition comprising:a mixture of a first thermal protective agent and a second thermal protective agent, the first thermal protective agent and the second thermal protective agent each being an isoamyl ester compound having a formula CH3(CH2)nCOOCH2CH(CH3)2, wherein n is an integer from 6 to 16, wherein the first thermal protective agent is different from the second thermal protective agent.

8. The hair care composition of claim 7, wherein n is selected from the group consisting of 6, 8, 10, 14, and 16.

9. The hair care composition of claim 8, wherein the composition further comprises a silicone compound.

10. A method for protecting hair from thermal damage, comprising: applying to hair a composition comprising an isoamyl ester compound of Formula I: R1-COO-R2, wherein n is an integer from 6 to 16, wherein: n=6 for Caprylate (C8:0), n=8 for Caprate (C10:0), n=10-16 for Cocoate (mixture of fatty acids, mainly C12-C18), n=14 for Palmitate (C16:0), and n=16 for Stearate (C18:0); andexposing the hair to heat from a heat styling device.

11. The method of claim 10, wherein n is 6, corresponding to isoamyl caprylate.

12. The method of claim 10, wherein n is 8, corresponding to isoamyl caprate.

13. The method of claim 10, wherein n is 14, corresponding to isoamyl palmitate.

14. The method of claim 10, wherein n is 16, corresponding to isoamyl stearate.

15. The method of claim 10, wherein the composition further comprises a silicone compound.

16. The method of claim 15, wherein the silicone compound is selected from the group consisting of dimethicone, cyclomethicone, and amodimethicone.

17. A hair styling system comprising:a heat styling device; anda hair care composition comprising an isoamyl ester compound selected from the group consisting of isoamyl caprylate / caprate, isoamyl cocoate, and isoamyl palmitate / stearate,wherein the hair care composition is configured to be applied to hair prior to using the heat styling device to provide thermal protection to the hair.

18. The hair styling system of claim 17, wherein the isoamyl ester compound is isoamyl caprylate / caprate represented by the formula: CH3(CH2)nCOOCH2CH(CH3)2, wherein n is 6 or 8.

19. The hair styling system of claim 17, wherein the isoamyl ester compound is isoamyl cocoate represented by the formula: CH3(CH2)nCOOCH2CH(CH3)2, wherein n is an integer from 10 to 16.

20. The hair styling system of claim 17, wherein the heat styling device is selected from the group consisting of a flat iron, curling iron, and blow dryer.

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