Hair cosmetic composition with hair heat protection effect

Abstract

The present invention relates to a cosmetic composition for hair, and more specifically, to a cosmetic composition for hair having a hair heat protection effect that can prevent hair damage caused by heat generated when using high-temperature heating devices such as hair dryers, curling irons, and hair irons, and contribute to maintaining hair moisture and reducing protein denaturation by forming a protective film.

Description

Technology Field

[0001] The present invention relates to a cosmetic composition for hair, and more specifically, to a cosmetic composition for hair having a hair heat protection effect that can prevent hair damage caused by heat generated when using high-temperature heating devices such as hair dryers, curling irons, and hair irons, and contribute to maintaining hair moisture and reducing protein denaturation by forming a protective film. Background Technology

[0002] In modern society, as interest in hairstyling grows alongside the increase in aesthetic desires, hair styling using high-temperature heat tools (e.g., hair dryers, curling irons, straighteners, curling irons, etc.) has become commonplace. Since these heat tools reach temperatures ranging from 60°C to over 230°C, repeated use damages the hair cuticle layer and causes denaturation of the hair's internal protein structure and dehydration, leading to physical and chemical damage such as reduced shine, split ends, and frizziness.

[0003] To address these issues, various hair cosmetic products containing functional ingredients that form a protective barrier on the hair or protect it from heat have been developed. Representative examples include silicone-based ingredients such as dimethicone and cyclopentasiloxane, along with protein derivatives and plant-derived oils, which have been utilized as heat-protective components.

[0004] However, silicone-based ingredients can accumulate on the surface of hair with long-term use, making it heavy and potentially causing hair loss or scalp problems; furthermore, as the preference for natural ingredients increases among some consumers, there is a noticeable trend of avoiding the use of synthetic chemicals.

[0005] Against this backdrop, there has recently been a growing need for the development of heat-protective compositions utilizing natural plant-derived ingredients or probiotic fermented products. In particular, plant-derived bioactive ingredients are attracting attention for their ability to alleviate heat stress on hair through antioxidant, anti-inflammatory, moisturizing, and protein-protective effects.

[0006] However, existing natural heat protection compositions have limitations as commercial products in terms of the duration of protective effects, spreadability, and formulation stability, and technologies to improve the efficiency of the fermentation process or the extraction rate of active ingredients have not been sufficiently developed.

[0007] Therefore, there is a need to develop a new hair protection composition that efficiently ferments and extracts natural ingredients, possesses a substantial heat damage prevention effect, and offers a pleasant user experience and formulation stability. Prior art literature

[0008] Korean Patent Publication No. 10-2492037 (Registered Jan. 19, 2023) "Composition for protecting hair from heat" The problem to be solved

[0009] In accordance with the above requirements, the present invention aims to provide a cosmetic composition for hair that effectively prevents physical and chemical damage to hair caused by the use of high-temperature heating devices and maximizes hair protection efficacy through fermentation technology based on naturally derived ingredients. In particular, the present invention aims to overcome the limitations of existing products and provide a safe and effective product that meets consumer preferences by configuring a composition capable of simultaneously performing functions such as cuticle protection, moisture retention, and heat stress relief while minimizing the use of synthetic silicone components. means of solving the problem

[0010] To achieve the above objectives, the present invention provides a hair cosmetic composition having a heat protection effect, characterized by including a mixed extract obtained by extracting a mixture of nettle, sunflower seeds, and coffee beans, which provides a heat protection effect.

[0011] In addition, the above mixed extract is characterized by being prepared by mixing nettle, sunflower seeds, and coffee beans in amounts of 0.01 to 99.98 weight% each, fermenting the mixture with a Lactobacillus fermentation strain, and then extracting.

[0012] In addition, the above-mentioned Lactobacillus fermentation strain is characterized by being one or more selected from the group consisting of Lactobacillus plantarum, Lactobacillus gasseri, Lactobacillus helveticus, Lactobacillus salivarius, and Lactobacillus reuteri.

[0013] In addition, the above mixed extract is characterized by being extracted with one or more extraction solvents selected from the group consisting of water, alcohols having 1 to 4 carbon atoms, propanediol, methylpropanediol, glycerin, butylene glycol, pentylene glycol, propylene glycol, ethylhexylglycerin, and hexanediol.

[0014] Furthermore, the cosmetic composition of the present invention is characterized by being formulated into any one of the formulations selected from the group of hair products consisting of shampoo, rinse, hair conditioner, hair treatment, hair pack, hair tonic, hair essence, hair grooming aid, pomade, hair spray, mousse, wax, gel, hair cream, hair lotion, hair oil, permanent wave, hair straightener, and hair fiber. Effects of the invention

[0015] The hair cosmetic composition according to the present invention can effectively prevent hair damage caused by high temperatures resulting from the use of heat styling tools, and by including naturally derived ingredients, it has the advantage of being safe to use with minimal irritation even on sensitive scalps or skin. Furthermore, the composition of the present invention forms a protective film on the hair to suppress moisture loss and impart shine and elasticity, thereby reducing dryness and frizz caused by heat, and has high industrial utility value as it can be applied to various formulations. Brief explanation of the drawing

[0016] FIG. 1 is a flowchart illustrating a method for preparing a cosmetic composition of the present invention. Figure 2 is a graph showing the results of the tensile strength test. Figure 3 is a graph showing the results of the root mean square roughness experiment. Figure 4 is a graph showing the results of the fracture resistance verification experiment. Specific details for implementing the invention

[0017] The following detailed descriptions relating to the present invention refer to the accompanying drawings, which are embodiments in which the present invention may be practiced and are illustrated as examples of such embodiments. These embodiments are described in detail to sufficiently enable those skilled in the art to practice the present invention. It should be understood that various embodiments of the present invention are different but need not be mutually exclusive. For example, specific shapes, structures, and characteristics described herein may be implemented in other embodiments without departing from the spirit and scope of the present invention in relation to one embodiment. Furthermore, it should be understood that the location or arrangement of individual components within each described embodiment may be changed without departing from the spirit and scope of the present invention.

[0018] Accordingly, the following detailed description is not intended to be taken in a limiting sense, and the scope of the invention is limited only by the appended claims, including all equivalents to those claimed therein, provided they are properly described. Similar reference numerals in the drawings refer to the same or similar functions across various aspects.

[0019] The terms used in this invention have been selected based on currently widely used general terms, taking into account their functions within the invention; however, these terms may vary depending on the intent of those skilled in the art, case law, the emergence of new technologies, etc. Additionally, in specific cases, terms have been arbitrarily selected by the applicant, and in such cases, their meanings will be described in detail in the relevant description of the invention. Therefore, the terms used in this invention should be defined not merely by their names, but based on their meanings and the overall content of the invention.

[0020] In the present invention, when a part is described as "comprising" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0022] Hereinafter, a cosmetic composition for hair having a hair heat protection effect according to the present invention will be described in detail.

[0024] A hair cosmetic composition having a hair heat protection effect according to the present invention is characterized by providing a heat protection effect by including a mixed extract obtained by extracting a mixture of nettle, sunflower seeds, and coffee beans.

[0025] Here, nettle refers to the above-ground part of *Urtica dioica* (Nettle), which has been widely used as a medicinal plant throughout Europe and Asia since ancient times and is characterized by its naturally rich silica content. Silica is a natural inorganic component that is effective in stabilizing the keratin structure, the main component of hair, and helping to align the cuticle layer, and can particularly act as a substitute for synthetic silicone. In addition, nettle contains large amounts of powerful antioxidants such as flavonoids, polyphenols, and vitamins A and C, which may contribute to protecting hair and scalp from reactive oxygen species (ROS) induced by heat.

[0026] Sunflower seeds are the seeds of the sunflower (Helianthus Annuus (Sunflower)) and include an outer shell that exhibits black and white stripes. Sunflower seeds contain large amounts of Vitamin E (tocopherol), linoleic acid, and oleic acid. In particular, thanks to the linoleic acid content, which is similar to the composition of sebum, they have high affinity for the scalp and hair and are effective in retaining moisture. Furthermore, the oil extracted from sunflower seeds forms a lipophilic protective film on the outer layer of hair, which is prone to dehydration due to heat, thereby inhibiting evaporation and contributing to maintaining shiny hair. Notably, alpha-tocopherol, an antioxidant, can also provide the effect of reducing oxidative damage to hair by inhibiting lipid oxidation caused by heat stress.

[0027] Coffee beans refer to the unroasted green beans of the coffee plant *Coffea Arabica*, containing chlorogenic acid, caffeine, polyphenols, and the like. Chlorogenic acid has powerful antioxidant and anti-inflammatory effects, while caffeine promotes blood circulation, which can help activate hair roots and prevent hair loss. It protects the tissues surrounding the hair follicles, which are easily damaged by heat, and polyphenols act to inhibit protein oxidation.

[0028] The mixture of the present invention contributes to the heat protection effect on hair through the characteristics of each of these components, and in the present invention, mutually complementary physiological activities can be induced by mixing, fermenting, and then extracting these three components.

[0029] In addition, the antioxidant capacity provided by each component of the mixture can prevent structural damage caused by reactive oxygen species (ROS) oxidizing cysteine ​​bonds within keratin chains, the main constituent protein of hair, thereby breaking disulfide bonds (-SS-) and altering the protein structure, and contribute to maintaining mechanical strength.

[0031] More specifically, the mixed extract of the present invention is characterized by being prepared by mixing nettle, sunflower seeds, and coffee beans in an amount of 0.01 to 99.98 weight% each, fermenting the mixture with a Lactobacillus fermentation strain, and then extracting.

[0032] At this time, it is critically desirable that the mixture be mixed in a weight ratio of 3:1:1, that is, 60% by weight of nettle, 20% by weight of sunflower seeds, and 20% by weight of coffee beans.

[0033] Here, "critically desirable" means a compositional ratio in which the abundant silica and antioxidant components contained in nettle contribute most significantly to the structural stability of the hair cuticle, the linoleic acid and tocopherol components of sunflower seeds act effectively for moisture protection and lipid film formation, and the caffeine and chlorogenic acid components of coffee beans complementarily exert effects of strengthening hair roots and providing antioxidant protection against heat stress. In other words, the above 3:1:1 mixing ratio was derived as the ratio that yields the best results in terms of preventing damage to the hair protein structure caused by heat stimulation, protecting the cuticle, inhibiting moisture evaporation, and imparting antioxidant activity by maximizing the functional synergy effect of each component.

[0034] The above-mentioned Lactobacillus fermentation strain may be one or more selected from the group consisting of Lactobacillus plantarum, Lactobacillus gasseri, Lactobacillus helveticus, Lactobacillus salivarius, and Lactobacillus reuteri.

[0035] In this case, the above-mentioned fermentation strains are microorganisms for which standard strains corresponding to their respective scientific names have been deposited and registered in accredited domestic and international microbial resource banks, and whose culture characteristics and genetic information are publicly disclosed; they correspond to biological resources that are commercially available for purchase in the market or can be easily secured and cultured by a person skilled in the art according to ordinary technical standards.

[0036] The above-mentioned Lactobacillus fermentation strains can contribute to improving absorption rates on the skin and hair and increasing bioavailability by breaking down high-molecular-weight antioxidant components, such as flavonoids and tannins contained in the mixed plant-based raw materials, into low-molecular-weight forms. In addition, these fermentation strains maintain the pH of the composition within a stable weakly acidic range by generating organic acids, such as lactic acid and acetic acid, during the fermentation process, thereby minimizing irritation to the scalp and hair and providing a mild user experience.

[0037] Lactobacillus plantarum is a representative strain with powerful antioxidant activity and the ability to produce antioxidant coenzymes such as glutathione and catalase-like enzymes. It can improve the absorption rate of flavonoids and polyphenols contained in plant-based ingredients by breaking them down into smaller molecules, while simultaneously contributing to strengthening the skin barrier and moisturizing effects.

[0038] Lactobacillus gasseri is a strain of interest for its anti-inflammatory and immunomodulatory effects, which can suppress scalp inflammation or hypersensitivity caused by heat damage and enhance hair protection effects through the production of antioxidant coenzymes and organic acid complexes.

[0039] Lactobacillus helveticus has excellent lactic acid production ability, which is advantageous for maintaining the pH of the composition at a stable weak acidic level, and can produce organic acids and short-chain fatty acids to improve the scalp microbial environment and exhibit anti-inflammatory effects.

[0040] Lactobacillus salivarius possesses powerful antibacterial and anti-inflammatory properties and is an effective strain for alleviating skin troubles and soothing the scalp. Its high ability to produce exopolysaccharides (EPS) makes it effective for imparting viscosity and moisturizing properties to fermented products.

[0041] Lactobacillus reuteri has excellent peptide-producing ability and can produce low-molecular-weight protein degradation products (peptides) similar to hair components during the fermentation process, which can contribute to penetration into the hair and repair of damage.

[0042] The Lactobacillus genus fermentation strain of the present invention is 10 6 ~ 10 8 It can be inoculated at an initial cell concentration of CFU / mL, and appropriately 10 7 Inoculating with CFU / mL is advantageous for ensuring fermentation efficiency and quality.

[0043] Meanwhile, it is desirable to select and inoculate only one species from the groups listed above as a fermentation strain of the Lactobacillus genus, in order to block competitive reactions between strains and maintain consistent quality, and Lactobacillus reuteri is suitable as a single strain.

[0044] Lactobacillus reuteri is a lactic acid bacterium derived from the intestinal microbiome of humans and animals, and during the fermentation process, it can produce a natural antimicrobial substance called reuterin in addition to organic acids such as lactic acid and acetic acid, which can contribute to increasing the microbial stability and preservation of the fermented product.

[0045] In particular, since it is effective in inhibiting oxidative damage to hair proteins, preventing cuticle breakdown caused by heat stimulation, and alleviating scalp inflammation through the low molecular weight and activation of plant-based antioxidant components, applying Lactobacillus reuteri as a fermentation strain can be a desirable choice for maximizing hair heat protection performance as a single strain due to these characteristics.

[0047] The above mixed extract may be extracted with one or more extraction solvents selected from the group consisting of water, alcohols having 1 to 4 carbon atoms, propanediol, methylpropanediol, glycerin, butylene glycol, pentylene glycol, propylene glycol, ethylhexylglycerin, and hexanediol, and known extraction methods such as hot water extraction and ultrasonic extraction using the extraction solvent may be applied, and a preferred example will be explained through the manufacturing method described below.

[0048] Mixture preparation step (S10) : Nettle, sunflower seeds, and coffee beans are mixed in an amount of 10.0 to 80.0 weight% each. Preferably, the mixture may be composed of 60 weight% nettle, 20 weight% sunflower seeds, and 20 weight% coffee beans.

[0049] In the preparation step (S10) of this mixture, it is possible to extract nettle, sunflower seeds, and coffee beans in their original state or to extract them after grinding, but it is preferable not to dry them before extraction in terms of preserving the active ingredients and the fermentation efficiency of the subsequent fermentation step (S20).

[0050] Fermentation stage (S20) : 10 Lactobacillus fermentation strains added to the above mixture 6 ~ 10 8Inoculate with an initial cell concentration of CFU / mL and ferment at 37℃ for 1 to 3 days.

[0051] Suitablely, 10 Lactobacillus reuteri in the mixture 7 It may be a step of inoculating with an initial cell concentration of CFU / mL and then fermenting at 37℃ for 3 days.

[0052] In this fermentation step (S20), purified water may be added as a buffer solution to maintain the activity of the fermentation strain and to accept the generated organic acid.

[0053] In addition, after the fermentation step (S20), a killing step (S21) may be included in which the fermented mixture is heated at 80 to 90°C for 10 to 30 minutes to kill the fermentation strains.

[0054] Extraction step (S30) : The above mixed extract may be extracted with one or more extraction solvents selected from the group consisting of water, alcohol having 1 to 4 carbon atoms, propanediol, methylpropanediol, glycerin, butylene glycol, pentylene glycol, propylene glycol, ethylhexylglycerin, and hexanediol at 50 to 60°C for 12 to 24 hours, and it is preferable to extract at 60°C for 18 hours.

[0055] At this time, it is preferable to use one or more solvents among propanediol, butylene glycol, and glycerin, either alone or in combination. This is because these extraction solvents are low-irritation solvents and moisturizers widely used in the extraction of natural products, and are effective in increasing the stability of active ingredients and extraction efficiency.

[0056] Specifically, propanediol enables the stable extraction of plant-based fermented ingredients and provides a gentle action on the hair and scalp. In particular, its excellent moisture-attracting properties can contribute to alleviating heat-induced moisture loss in hair. Butylene glycol, based on its high polarity and solubility, enhances the extraction efficiency of antioxidant and moisturizing components within the fermentation product and can help inhibit cuticle damage by forming a protective barrier after absorption into the hair. Additionally, glycerin is effective in preventing hair dryness and inhibiting heat denaturation based on its high moisture retention ability, and can also contribute to preventing protein oxidative damage caused by free radicals through its antioxidant properties.

[0057] After this extraction step (S30), a filtration step (S31) to remove solids may be performed, and subsequently, depending on what formulation the cosmetic composition is to be formulated into in the formulation step (S40), a reduced-pressure concentration step (S32) may be included to adjust the concentration and viscosity.

[0058] Formulation step (S40) The cosmetic composition of the present invention may be formulated into any one of the formulations selected from the group of hair products consisting of shampoo, rinse, hair conditioner, hair treatment, hair pack, hair tonic, hair essence, hair grooming aid, pomade, hair spray, mousse, wax, gel, hair cream, hair lotion, hair oil, permanent wave, hair straightener, and hair fiber, and provided to users to ensure industrial utility value, and the formulation may be carried out according to known methods.

[0060] Below, the effects of the hair cosmetic composition having a hair heat protection effect according to the present invention will be examined in detail through examples, comparative examples, and experimental examples.

[0062] Example 1. A composition extracted by mixing nettle, sunflower seeds, and coffee beans and fermenting with Lactobacillus reuteri.

[0063] The experimental composition of Example 1 was prepared according to the following manufacturing process.

[0064] Mixture preparation step (S10): A mixture was prepared by mixing 60% by weight of nettle in its raw state, 20% by weight of sunflower seeds, and 20% by weight of coffee beans.

[0065] Fermentation step (S20): 20 volume% of purified water is added to the above mixture, and then 10 Lactobacillus reuteri are added. 7 Inoculated with an initial cell concentration of CFU / mL and fermented at 37℃ for 3 days.

[0066] Killing step (S21): Afterwards, the fermentation strain was killed by heating at 80°C for 20 minutes.

[0067] Extraction step (S30): An extraction solvent mixed in equal amounts of propanediol, butylene glycol, and glycerin was added to the fermented mixture at 150 volume% relative to the fermented mixture, and then extracted at 60°C for 18 hours to prepare a mixed extract.

[0068] Filtration step (S31): The mixed extract was filtered with a 200 mesh filter to remove solids.

[0070] Comparative Example 1. Example excluding nettle from the mixture

[0071] The experimental composition of Comparative Example 1 was prepared by changing the mixture preparation step (S10) of Example 1 above to a step of preparing a mixture by mixing 50% by weight of sunflower seeds in their raw state and 50% by weight of coffee beans.

[0073] Comparative Example 2. Example excluding sunflower seeds from the mixture

[0074] The experimental composition of Comparative Example 2 was prepared by changing the mixture preparation step (S10) of Example 1 above to a step of preparing a mixture by mixing 75% by weight of nettle in its raw state and 25% by weight of coffee beans.

[0076] Comparative Example 3. Example excluding coffee beans from the mixture

[0077] The experimental composition of Comparative Example 3 was prepared by changing the mixture preparation step (S10) of Example 1 above to a step of preparing a mixture by mixing 75% by weight of nettle in its raw state and 25% by weight of sunflower seeds.

[0079] Comparative Example 4. Example excluding the fermentation process

[0080] The experimental composition of Comparative Example 4 was prepared by extracting the mixture excluding the fermentation step (S20) and the death step (S21) from the manufacturing method of Example 1 above.

[0082] Example 2. Example of using Lactobacillus plantarum as a fermentation strain

[0083] The experimental composition of Example 2 was prepared by replacing the fermentation strain in the fermentation step (S20) of Example 1 with Lactobacillus plantarum.

[0085] Example 3. Example of using Lactobacillus gasseri as the fermentation strain

[0086] The experimental composition of Example 3 was prepared by replacing the fermentation strain in the fermentation step (S20) of Example 1 with Lactobacillus gasseri.

[0088] Example 4. Example of using Lactobacillus salivarius as the fermentation strain

[0089] The experimental composition of Example 4 was prepared by replacing the fermentation strain in the fermentation step (S20) of Example 1 with Lactobacillus salivarius.

[0091] Example 5. Example of using Lactobacillus helveticus as a fermentation strain

[0092] The experimental composition of Example 5 was prepared by replacing the fermentation strain in the fermentation step (S20) of Example 1 with Lactobacillus helveticus.

[0094] Comparative Example 5. Example of applying Bacillus subtilis as the fermentation strain

[0095] The experimental composition of Comparative Example 5 was prepared by replacing the fermentation strain with Bacillus subtilis in the fermentation step (S20) of Example 1 above.

[0097] The experimental compositions of Examples 1 to 5 and Comparative Examples 1 to 5 prepared as described above were stabilized at 25°C for 5 hours, and then used without a separate formulation process to confirm the exact effect.

[0099] Sample settings

[0100] The entire undamaged human hair (15 cm) of a woman in her 20s was immersed in the experimental compositions of Examples 1 to 5 and Comparative Examples 1 to 5, and then dried at room temperature for 30 minutes, and human hair that was not treated with the experimental compositions was kept as a control group.

[0102] Experimental Example 1. Measurement of tensile strength after heat treatment

[0103] 1) Experimental Method

[0104] The samples of the control group, Examples 1 to 5, and Comparative Examples 1 to 5 were subjected to one total heat treatment using a hair iron (Babyliss Pro Nano Titanium™, USA) preheated to 180°C.

[0105] The treated samples were cut into 5 cm lengths and secured to the clamps of a Universal Testing Machine (Instron 3343, Instron Corp., USA). The clamp spacing was set to 30 mm, and tension was applied until the hair fractured by maintaining a tensile speed of 10 mm / min. The maximum tensile stress (MPa) measured at this point was recorded as the tensile strength. Measurements were repeated five times for each sample under the same conditions, and the average value was calculated as the final result.

[0107] 2) Experimental Results

[0108] The experimental results are shown in Table 1 below.

[0109] Sample Tensile strength (MPa) Example 1 18.2 Comparative Example 1 12.5 Comparative Example 2 14.0 Comparative Example 3 13.3 Comparative Example 4 10.8 Example 2 13.5 Example 3 17.1 Example 4 16.9 Example 5 17.3 Comparative Example 5 16.8 control group 9.7

[0110] As shown in Table 1, Example 1 exhibited a maximum tensile strength of 18.2 MPa, suggesting that it is effective in stabilizing the keratin structure of hair damaged by heat stimulation. Hair is composed mostly of keratin protein, and heat treatment denatures this structure, causing a rapid decrease in mechanical strength.

[0111] Nettle contains a large amount of natural silica, which interacts with keratin to reinforce internal hydrogen bonds in the hair and maintain alignment between cuticles; meanwhile, the linoleic acid and tocopherol in sunflower seeds form a lipophilic protective film on the hair sheath, contributing to the inhibition of moisture evaporation and the maintenance of flexibility. The chlorogenic acid and caffeine in coffee beans inhibit protein oxidation through their antioxidant action against reactive oxygen species generated by heat, and it can be inferred that the combined action of these factors led to an improvement in tensile strength.

[0112] The Lactobacillus lutea used in the fermentation of Example 1 produces luterin, organic acids, peptides, etc., during the fermentation process. These substances are low-molecular-weight metabolites with high penetration into the hair cuticle; upon absorption into the hair, they contribute to the repair of damaged keratin chains and the strengthening of bonding strength. Furthermore, the slightly acidic environment formed during the fermentation process induces cuticle shrinkage, which appears to have had a positive effect on surface sealing and the restoration of shine.

[0113] Meanwhile, Comparative Examples 1 to 3, which are compositions excluding specific raw materials, each showed values ​​of only 12.5 to 14.0 MPa, and in particular, Comparative Example 1, which excluded nettle, was the lowest at 12.5 MPa. This implies that silica plays a key role in keratin stabilization. Comparative Example 4, in which fermentation was omitted, dropped sharply to 10.8 MPa, which demonstrates that low-molecular-weight bioactive substances produced through fermentation play a much more important role in the protective effect than the natural product itself.

[0114] Comparative Example 5 (Bacillus subtilis fermentation) was found to be 13.5 MPa, which appears to be because the major metabolites produced by Bacillus subtilis during fermentation are concentrated in polysaccharides and inorganic acids, and the ability to produce polyphenol degrading enzymes or antioxidant coenzymes is relatively insufficient.

[0115] Examples 2 to 5, which used different fermentation strains within the genus Lactobacillus, showed results of 16.8 to 17.3 MPa, which were slightly lower than Lactobacillus reuteri but were all superior to Comparative Example 5 (13.5 MPa) which used Bacillus subtilis.

[0116] The experimental results of Experimental Example 1 show that the combination of three natural ingredients in the cosmetic composition of the present invention and the application of Lactobacillus fermentation strains, particularly Lactobacillus reuteri, provide excellent effects in terms of protection against heat damage to hair and maintenance of mechanical strength.

[0118] Experimental Example 2. Analysis of Hair Cuticle Damage via Root Mean Square Roughness (Rq)

[0119] 1) Experimental Method

[0120] The samples of the control group, Examples 1 to 5, and Comparative Examples 1 to 5 were subjected to one total heat treatment using a hair iron (Babyliss Pro Nano Titanium™, USA) preheated to 180°C.

[0121] Afterwards, each sample was fixed to a metal slide, and the root mean square roughness (Rq) at five points was measured using a 3D non-contact optical surface profiler (ContourGT-X, Bruker) to calculate the average value.

[0122] Here, root mean square roughness is calculated as the square root of the mean square of the height deviation of each point within the observation area and is an indicator that can quantitatively evaluate the overall mechanical damage of the surface or the alignment of the cuticle.

[0124] 2) Experimental Results

[0125] The experimental results are shown in Table 2.

[0126] Sample Root mean square roughness (Rq) Example 1 1.05 Comparative Example 1 1.42 Comparative Example 2 1.30 Comparative Example 3 1.35 Comparative Example 4 1.60 Example 2 1.12 Example 3 1.14 Example 4 1.16 Example 5 1.11 Comparative Example 5 1.33 control group 1.85

[0127] As shown in Table 2, the control group showed the highest root mean square roughness of 1.85 μm, indicating that severe cuticle damage occurred.

[0128] In Comparative Examples 1 to 3, in which one of nettle, sunflower seed, and coffee bean was excluded from the mixture, the root mean square roughness was 1.30 to 1.42 μm, respectively, and the alignment of the cuticles was incompletely restored, confirming that the protective effect of the composition is reduced if even one of the mixture components is missing.

[0129] Comparative Example 4 is a case where fermentation was omitted, exhibiting a root mean square roughness of 1.60 μm, which indicates a very insufficient protective effect against thermal stimulation. This is interpreted as being due to the fact that the active ingredient was not broken down into low molecular weights through the fermentation process and had low bioavailability.

[0130] Comparative Example 5, which used Bacillus subtilis as the fermentation strain, showed a root mean square roughness of 1.33 μm, and although fermentation was carried out, the effect of improving roughness was somewhat lower compared to the example.

[0131] Meanwhile, Example 1 had the lowest root mean square roughness at 1.05 μm, suggesting that cuticle damage was minimal. The silica component of nettle contributes to the stabilization of the hair structure, the linoleic acid and tocopherol of sunflower seeds prevent moisture loss due to heat, and the chlorogenic acid and caffeine of coffee beans inhibit protein oxidation, thereby providing an antioxidant protective effect. It is believed that reuteri contributed to maximizing the penetration and activity of active ingredients and maintaining the hair cuticle in an aligned state by generating reuterin, peptides, organic acids, etc., during the fermentation process.

[0132] In Examples 2 to 5, in which Lactobacillus plantarum, gasseri, salivarius, and helveticus were applied respectively, the root mean square roughness was 1.11 to 1.16 μm, indicating that it was effective in inhibiting heat damage, and it can be seen that the unique antioxidant coenzyme induction ability, anti-inflammatory action, pH stabilization, and moisturizing effect of each strain acted in combination.

[0134] Experimental Example 3. Confirmation of fracture resistance

[0135] 1) Experimental Method

[0136] Heat stimulation was repeatedly applied to the samples of the control group, Examples 1 to 5, and Comparative Examples 1 to 5 using a hair iron (Babyliss Pro Nano Titanium™, USA) preheated to 180°C.

[0137] Specifically, both ends of the sample were fixed to a clamp, and a heat stimulus was applied by reciprocating a hair iron at a constant speed. After one reciprocating treatment, the fracture status was checked, and this process was repeated until each sample fractured.

[0138] For each sample, measurements were repeated 5 times under the same conditions, and the average value of the number of reciprocating cycles performed until fracture was calculated as the final result.

[0140] 2) Experimental Results

[0141] The experimental results are shown in Table 3 below.

[0142] Sample Round trips (times) Example 1 238.7 Comparative Example 1 162.3 Comparative Example 2 168.9 Comparative Example 3 165.4 Comparative Example 4 151.1 Example 2 223.4 Example 3 217.8 Example 4 212.1 Example 5 221.0 Comparative Example 5 172.6 control group 134.6

[0143] Example 1 demonstrated an excellent heat protection effect by not causing fracture up to an average of 238.7 reciprocating heat treatments. This is analyzed as a result of the silica content of nettle contributing to the stabilization of the keratin structure within the hair, and the linoleic acid and tocopherol of sunflower seeds forming a lipid film and inhibiting moisture evaporation.

[0144] In addition, low molecular weight components such as reuterin, peptides, and organic acids produced by Lactobacillus reuteri fermentation are believed to have inhibited the denaturation of hair proteins by promoting the absorption of these active substances and increasing physiological activity.

[0145] Examples 2 to 5, in which the fermentation strain was modified, showed high fracture resistance of approximately 212 to 223 times, but it was confirmed that this was slightly lower compared to Example 1.

[0146] On the other hand, Comparative Example 5, which used Bacillus subtilis, fractured 172.6 times and showed a lower effect than Examples 1 to 5, and Comparative Examples 1 to 4, in which fermentation was omitted or the main raw material was excluded, recorded a fracture count of around 150 times, showing a significant decrease in effectiveness.

[0147] In particular, the control group showed the lowest value at 134.6 times, confirming that the destruction of protein structure due to heat stress proceeded rapidly when the composition was not treated.

[0149] In summary, the hair cosmetic composition having a hair heat protection effect according to the present invention is characterized by effectively suppressing complex heat stress, such as protein denaturation, moisture evaporation, and cuticle damage that occurs when hair is exposed to high-temperature heat treatment, through natural ingredients and biological fermentation.

[0150] In particular, by combining plant raw materials with distinct biological activities—namely nettle, sunflower seeds, and coffee beans—and fermenting them with Lactobacillus strains, a complex heat protection mechanism was achieved that is difficult to expect from single ingredients or simple mixtures. This strategy maximizes the potential functions of naturally derived ingredients while also meeting the demand for developing sustainable cosmetic raw materials that are hypoallergenic to the human body.

[0151] Furthermore, this invention presents a clear alternative to existing technologies by achieving hair protection functions without relying on synthetic silicone-based components. By experimentally demonstrating that changes in component structure and enhanced absorption through fermentation lead to improved physical stability of actual hair, it suggests a new direction for the research of functional cosmetic compositions and possesses potential for industrial application.

[0153] Although the present invention has been described together with the accompanying drawings, this is merely one example among various embodiments containing the gist of the invention, and its purpose is to enable those skilled in the art to easily implement it; it is clear that the present invention is not limited to the embodiments described above. Accordingly, the scope of protection of the present invention should be interpreted by the claims below, and all technical ideas within an equivalent scope by modification, substitution, replacement, etc., without departing from the gist of the invention shall be included within the rights of the present invention. Furthermore, it is clarified that some components in the drawings are provided in an exaggerated or reduced size compared to the actual form to more clearly explain the configuration. Explanation of the symbols

[0154] (S10): Mixture preparation step (S20): Fermentation step (S21): Death stage (S30): Extraction stage (S31): Filtration step (S32): Pressure concentration step (S40): Formulation step

Claims

Claim 1 A mixture of nettle, sunflower seeds, and coffee beans After fermenting with Lactobacillus strains A cosmetic composition for hair having a heat protection effect, characterized by including an extracted mixed extract to provide a heat protection effect. Claim 2 A cosmetic composition for hair having a heat protection effect on hair, characterized in that, in claim 1, the mixed extract is prepared by fermenting a mixture of nettle, sunflower seeds, and coffee beans in an amount of 0.01 to 99.98 weight% each with a Lactobacillus fermentation strain and then extracting. Claim 3 A cosmetic composition for hair having a heat-protective effect on hair, characterized in that, in claim 2, the fermentation strain of the genus Lactobacillus is one or more selected from the group consisting of Lactobacillus plantarum, Lactobacillus gasseri, Lactobacillus helveticus, Lactobacillus salivarius, and Lactobacillus reuteri. Claim 4 A cosmetic composition for hair having a heat-protective effect on hair, wherein, in claim 1, the mixed extract is extracted with one or more extraction solvents selected from the group consisting of water, alcohol having 1 to 4 carbon atoms, propanediol, methylpropanediol, glycerin, butylene glycol, pentylene glycol, propylene glycol, ethylhexylglycerin, and hexanediol. Claim 5 A cosmetic composition for hair having a hair heat protection effect, characterized in that, in claim 1, it is formulated into any one formulation selected from the group of hair products consisting of shampoo, rinse, hair conditioner, hair treatment, hair pack, hair tonic, hair essence, hair grooming aid, pomade, hair spray, mousse, wax, gel, hair cream, hair lotion, hair oil, permanent wave, hair straightener, and hair fiber.

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