Cellulose nanofiber-embedded dried components

Abstract

The objective of the present invention is to provide a new component embedding technology using CNF. [Solution] Cellulose nanofibers (CNF) and added components are mixed in an aqueous medium and dried to provide a component-embedded dried body characterized in that the components are physically embedded within the aggregated structure of the CNF.

Description

[Technical Field]

[0001] The present invention relates to a technology for obtaining a dried product in which ingredients are physically embedded by utilizing the dry aggregation properties of cellulose nanofibers (CNF). The dried product can be provided in a form that can be redispersed to some extent in a dispersion medium such as water while maintaining the embedded structure. Furthermore, this structure has the ability to sustain the release of active ingredients and functional components. [Background technology]

[0002] Cellulose nanofibers (CNFs) have a nano-sized fibrous structure and are highly dispersible, highly viscous, and film-forming, making them widely used in foods, cosmetics, pharmaceuticals, industrial materials, etc. For these applications, CNFs are often first dried and made into powder form, and then re-dispersed in an aqueous system as needed.

[0003] However, CNFs are known to undergo irreversible aggregation during the drying process, significantly reducing their redispersibility, and this characteristic has been an issue in terms of storage and distribution. Development of CNF redispersion technologies has been progressing. For example, Patent Document 1 discloses a technology for obtaining CNF with excellent redispersibility by performing an alkaline cooking process followed by bleaching and chemical control using food-acceptable chemicals, and then combining this with a mechanical defibration process. Furthermore, Non-Patent Document 1 proposes a process that combines solvent substitution and freeze-drying as a means of suppressing aggregation during drying of CNF, and further investigates in detail the effects of stirring conditions and the use of auxiliary agents during redispersion. Furthermore, Non-Patent Document 2 reports a technology that improves redispersibility after drying by modifying the CNF surface with a polymer auxiliary such as carboxymethyl cellulose (CMC) and controlling physicochemical interactions.

[0004] While both methods provide effective means for improving the redispersibility of CNF, they can be accompanied by issues such as the addition of chemicals, process complexity, and increased costs. Furthermore, in fields requiring high safety and environmental compatibility, such as food and pharmaceutical applications, simpler and more sustainable methods are needed. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2020-165042 [Non-patent literature]

[0006] [Non-patent document 2] Yano et al., “Redispersion of Dried Cellulose Nanofibers Prepared by Solvent Exchange and Freeze Drying,” Cellulose, 2018 [Non-patent document 3] Tanaka et al., “Redispersion of Dried Cellulose Nanofibers by Surface Modification Using Carboxymethylcellulose,” J. Appl. Polym. Sci., 2020 Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide a sustained-release dried product that can be made only from naturally occurring ingredients without requiring chemical reactions or expensive equipment. [Means for solving the problem]

[0008] The objective of this invention is to provide an embedded dried product made entirely of naturally occurring materials without chemical synthesis, by actively utilizing the cohesion that occurs with drying of CNF as a physical embedding mechanism for ingredients. While this cohesion structure has the potential to be used for microstructural control and substance encapsulation, its effect on the retention and sustained release of fragrances and active ingredients has not been fully investigated. This dried product can be redispersed to some extent in water or other dispersing media while maintaining its embedded structure, and furthermore, it has a structure that can exhibit sustained release of ingredients, thereby solving the problems of the prior art.

[0009] The inventors focused on the characteristic of cellulose nanofibers (CNFs) that they tend to aggregate when dried, which has traditionally been considered a drawback, and conducted extensive research into whether this characteristic could be actively utilized as a means of embedding components.

[0010] Conventional microencapsulation techniques often require chemical reactions or complex processes, posing various challenges in terms of cost, safety, and environmental impact. In response, the inventors have developed a new method that enables component encapsulation using only the simple physical process of drying. Furthermore, by using only naturally derived components for the constituent materials, including CNF and the components to be encapsulated, the inventors have achieved both reduced environmental impact and safety during use.

[0011] Furthermore, the obtained ingredient-embedded dried body can be developed into a variety of formulation forms, such as powder, sheet, and gel, allowing for flexible design according to the application, making it applicable to a wide range of fields, including food, cosmetics, pharmaceuticals, agriculture, and environmental materials. Thus, the challenge of "how to return CNF to its original dispersed state after drying" is a technological direction that many CNF-related researchers and companies are pursuing. In conventional technologies, many innovations have been reported to improve the redispersibility of CNF, including drying methods, additives, and interface modifications.

[0012] However, this invention takes a fundamentally different approach from conventional methods in that it is based on the new idea of ​​"assuming a decrease in redispersibility and actively utilizing it." In other words, the components are immobilized in an entangled state in the aggregated structure that occurs when the CNF is dried, making it possible to perform functions such as embedding, retention, and sustained release in the dry state without the need for redispersion.

[0013] This idea fundamentally reconsiders the premise of CNF usage, which is to "redisperse and use," and proposes a new application form that gives functionality to the dried CNF structure itself.

[0014] The present invention has the following technical features and is considered to have novelty and inventive step based on evaluation criteria different from those of the prior art. No need to re-disperse even after drying: CNF does not need to be re-dispersed to function. Ingredient retention and sustained release: Ingredients are retained in the physical network within the CNF dry structure, allowing for gradual release during use. Simple manufacturing method: The desired function can be achieved through the simple process of drying alone, without the need for complex processes such as high-energy defibration, interface modification, or re-dispersion control. Therefore, the present invention is a technology based on a new form of use for CNF, namely, utilizing its functionality as a dry structure, and is unique and has high applicability within the technical field.

[0015] The present invention provides a dry material with an ingredient embedded in CNF by a production method including the following steps 1 to 3: 1. Disperse cellulose nanofibers (CNF) in an aqueous medium. 2. Add any desired additives (e.g., fragrances, vitamins, oils, medicinal ingredients, etc.) to the dispersion. 3. By drying the mixture, the CNF forms an aggregated structure and physically embeds the added ingredients. The resulting dried product can be made into a powder or sheet, and can be redispersed into fine particles by adding it back into water or an emulsion, etc. At this time, the embedded components have the property of being slowly released over time. In particular, unmodified CNF obtained by mechanical defibration tends to form a strong aggregate structure when dried, making it suitable for the present invention in terms of embedding effect and sustained release control. The present invention also includes the following aspects: [1] A component-embedded dried body characterized by mixing cellulose nanofiber (CNF) and an added component in an aqueous medium and drying the mixture, thereby physically embedding the component within the aggregated structure of the CNF. [2] The ingredient-embedded dried material according to [1], wherein the ingredient-embedded dried material is in the form of a powder or sheet. [3] The ingredient-embedded dried material according to [1] or [2], wherein the added ingredient is gradually released when redispersed in a liquid medium. [4] The ingredient-embedded dried material described in any one of [1] to [3], characterized in that the CNF is unmodified CNF obtained by mechanical defibration. [5] The ingredient-embedded dried material according to any one of [1] to [4], characterized in that the additive ingredient is an oily ingredient and is dispersed in an aqueous medium in combination with a surfactant. [6] The component-embedded dried body according to any one of [1] to [5], characterized in that the CNF is a CNF that has been chemically modified by either TEMPO oxidation, phosphate esterification, carboxymethylation, or cationization. [7] The component-embedded dried body described in any one of [1] to [6], characterized in that when redispersed in a liquid medium, the CNF is uniformly dispersed and the function of the added component is maintained. [8] A cosmetic comprising the ingredient-embedded dry material according to any one of [1] to [7]. [9] A food or beverage product comprising the ingredient-embedded dried material according to any one of [1] to [8].

[10] A sanitary treatment agent comprising the ingredient-embedded dried material according to any one of [1] to [9].

[11] A pesticide comprising the ingredient-embedded dry product according to any one of [1] to

[10] .

[12] A fertilizer comprising the ingredient-embedded dried material according to any one of [1] to

[11] .

[13] A medical composition comprising the ingredient-embedded dry material according to any one of [1] to

[12] . [Effects of the Invention]

[0016] The structure of the present invention eliminates the need for the complicated processes previously required, such as interfacial polymerization, emulsification, and high-pressure treatment, and makes it possible to realize an embedded body that is safe and has a low environmental impact, using only naturally occurring materials. DETAILED DESCRIPTION OF THE INVENTION

[0017] One aspect of the present invention provides an ingredient-embedded dried body, characterized in that cellulose nanofibers (CNF) and an additive component are mixed in an aqueous medium and dried, thereby physically embedding the additive component within the aggregated structure of the CNF.

[0018] The ingredient-embedded dried product of the present invention can provide the following effects: It is possible to embed ingredients using only naturally derived ingredients without using chemical reactions or expensive equipment. The resulting structure has microcapsule-like functions and is highly safe for use in the food, cosmetics, and pharmaceutical industries. It can be provided in a variety of forms, such as powder, sheet, and gel, depending on the purpose. It is effective in applications that utilize sustained release effects, such as sustained fragrance, long-term retention of medicinal ingredients, and sustained moisture retention. Combining it with chemically modified CNF also enables advanced release control.

[0019] In this invention, "cellulose nanofiber (CNF)" refers to a nanoscale fibrous structure whose main component is cellulose, and there are no particular limitations on its manufacturing method or raw materials. CNF manufacturing methods include mechanical defibration, enzymatic defibration, and chemical treatment (e.g., TEMPO oxidation, carboxylation, phosphoric acid treatment, etc.), and the CNF obtained by these methods each exhibit different characteristics in terms of dispersibility, viscosity, water retention, and mechanical properties.

[0020] Additionally, for purposes of the present invention, "CNF" also includes structurally or functionally equivalent nanofibrous materials such as: Ultrafine cellulose (e.g., microfibrillated cellulose (CMF), nanocrystalline cellulose (CNC), microcrystalline cellulose (MCC)) Micronized cellulose (e.g., microfibrillated cellulose (MFC)) Nanofibers derived from bacterial cellulose Nanofibers based on cellulose derivatives (e.g., TEMPO-oxidized CNF) - Composite nanofibers with some non-cellulose materials. If necessary, non-cellulose nanofibers of plant or natural origin, such as chitin nanofibers and lignin-based nanofibers, or materials with equivalent properties such as viscosity, film-forming ability, and reinforcing ability, can be used in combination with or instead of CNF.

[0021] These nanofiber materials can be used alone or in combination to adjust properties such as structural stability of the dried body, controlled release of ingredients, dispersibility, and water resistance. Conventionally, CNF has been considered to have a disadvantage in that it aggregates during drying, resulting in reduced redispersibility. However, in the present invention, this low redispersibility itself is actively utilized, and the stable microcapsule-like structure formed during drying improves the retention and control of functional ingredients. It achieves release.

[0022] In other words, the components encapsulated at the nano level by CNF are retained within the microstructure even after drying, and are gradually released depending on the external environment. This structural design, which considers "not returning to nano" to be an advantage, is not seen in conventional CNF technology, and clearly demonstrates the technological uniqueness of this invention.

[0023] The "cellulose nanofibers (CNF)" that can be used in the present invention generally have a diameter of 100 nm or less.

[0024] Raw materials for CNFs are not limited to known materials. Examples include wood-based materials such as conifers (e.g., cedar, pine, spruce) and hardwoods (e.g., maple, beech, poplar), agricultural residue-based materials such as rice straw, wheat straw, corn stalks, bagasse (sugarcane residue), hemp husks, cottonseed husks, soybean husks, and pineapple leaves, herbaceous plant-based materials such as kenaf, hemp, jute, and ramie, industrial by-product materials such as papermaking sludge, sawmill chips, and by-product lignin-containing cellulose, textile waste materials such as waste paper, used cotton clothing, and recycled cotton, food waste materials such as fruit peels (orange peel, banana peel), potato pomace, and other vegetables, marine plant-derived materials such as seaweed (cellulose-containing species: Cladophora, etc.), and pure cellulose materials such as α-cellulose, microcrystalline cellulose (MCC), and bacterial cellulose (BC). It is preferable to use vegetable food residues as a raw material, as this will contribute to solving the problem of large amounts of vegetable waste generated at the consumption stage in recent years. Methods for producing CNF from such plant-based food residues and food manufacturing by-products are known. For example, Japanese Patent Application Laid-Open No. 2020-165042 discloses a method for producing CNF by digesting food manufacturing by-products containing plant fibers using alkali acceptable for use in food, washing the digested product with water, bleaching the resulting pulp containing cellulose and hemicellulose with a food-grade chemical, and then washing it again with water. The pulp is then mechanically defibrated and pulverized.

[0025] In the present invention, the "vegetables" that can be used as the raw material for cellulose nanofibers (CNFs) are not limited to any particular type, as long as they can be used to produce CNFs. Examples include leafy vegetables (cabbage, spinach, lettuce, komatsuna (Japanese mustard spinach), Chinese cabbage, garland chrysanthemum, and mizuna (Japanese mustard greens), fruit vegetables (tomato, cucumber, eggplant, bell pepper, paprika, pumpkin, zucchini, bitter melon, and okra), root vegetables (radish, carrot, potato, sweet potato, burdock, taro, turnip, beet, and lotus root), stem vegetables (asparagus, celery, broccoli stalks, butterbur, and bamboo shoots), flower vegetables (broccoli and cauliflower), bulbs (onion, garlic, scallions, and green onions), and beans (edamame (green soybeans), broad beans, snap peas, and kidney beans).

[0026] Furthermore, the vegetables are not limited to raw vegetables, but may be processed vegetables that have been subjected to common food processing such as washing, disinfection, cutting, crushing, peeling, heating, cooling, freezing, drying, etc., and also include vegetables or vegetable fragments that are food residues or food waste.Furthermore, the parts of the vegetables used are not particularly limited, and various parts such as leaves, stems, roots, fruits, flowers, petals, corms, bulbs, and seeds can be used.

[0027] As used herein, "vegetable fragments" refers to vegetables or portions thereof that have been processed to a certain size by shredding or crushing. The size of the vegetable fragments is preferably about 0.3 to 1.5 cm on the long side, and more preferably about 0.5 to 0.8 cm. If the size is less than 0.3 cm, the vegetable fragments are likely to be washed away during washing, while if it exceeds 1.5 cm, unevenness is likely to occur during softening, reduction, and bleaching treatments, so neither is desirable. There are no particular limitations on the method of shredding or crushing, and commercially available mixers, slicers, food processors, etc. can be used.

[0028] In this specification, "additive components" refers to components that are added to an aqueous medium containing cellulose nanofibers (CNF) and are retained and immobilized in the CNF structure by the drying process of the CNF. These additive components include a wide range of molecular species, from low-molecular-weight compounds to high-molecular-weight substances, and can exhibit functions such as embedding, retention, and sustained release through physical and chemical interactions with the CNF microstructure.

[0029] The additive components are exemplified based on the following classifications, but the present invention is not limited to these. (1)Low molecular compounds These are organic and inorganic compounds with a molecular weight of approximately 1,000 or less that can penetrate and be retained in the gaps between CNFs and in the mesh structure, allowing them to be stably embedded in the dry structure. Examples include fragrances (linalool, geraniol, etc.), vitamins (vitamin C, B group, E, etc.), organic acids (lactic acid, citric acid, acetic acid, etc.), inorganic salts (sodium chloride, phosphate, potassium nitrate, etc.), antibacterial agents, preservatives, and UV absorbers.

[0030] (2) Amino acids and their derivatives They are used as single amino acids or short-chain peptides and have functions such as nutritional support, moisturizing, and pH buffering. Examples include glutamic acid, arginine, serine, histidine, dipeptides, tripeptides (e.g., carnosine), and acetylated amino acids (acetylglutamine, etc.).

[0031] (3) Nucleic acids and nucleic acid-related substances These additives are used for signal transduction, regulation, or physiological activity, and their stable retention and slow release make them suitable for pharmaceutical, cosmetic, and agricultural applications. Examples include nucleic acid-related compounds such as DNA, RNA, oligonucleotides, nucleic acid bases (adenine, guanine, cytosine, etc.), ATP, cAMP, and NAD+.

[0032] (4) Polymer compounds (natural or synthetic) It has a high affinity with CNF and is stably fixed within the structure through physical networks and hydrogen bonds. It contributes to the strength, viscosity, and release properties of the dried structure. Examples include hydrolyzed keratin, gelatin, collagen, hyaluronic acid, polysaccharides (alginic acid, pectin, chitosan, dextrin, etc.), proteins (casein, globulin, etc.), and synthetic polymers (polyvinyl alcohol, polyethylene glycol, etc.).

[0033] (5) Lipids / surfactants They are stabilized together with CNF in the dry structure for the purposes of membrane formation, moisturizing, assisting skin penetration, and stabilizing emulsification. Examples include ceramides (ceramide NP, AP, etc.), phospholipids (lecithin, etc.), medium-chain fatty acids, vegetable oils, wax components, and nonionic and amphoteric surfactants.

[0034] As used herein, the term "aqueous medium" refers to a liquid primarily composed of water, which may optionally contain a water-soluble organic solvent, a surfactant, salts, a pH adjuster, etc. The proportion of water is 50% or more, preferably 70% or more, based on the mass or volume of the entire medium. Examples of "aqueous medium" in the present invention include pure water, a mixture of water and ethanol or isopropanol, and a system in which a surfactant, salts, a pH adjuster, a polymer dispersant, etc., has been added to water. These are selected depending on the dispersibility, stability, and interaction control of the CNF and added components.

[0035] In the present invention, "embedding" refers to the phenomenon in which CNF physically entraps and retains other components, such as aroma compounds and amino acids, within its structure during the drying and agglomeration process. This is different from conventional encapsulation, which has a distinct internal and external structure, and is a physical incorporation phenomenon resulting from the spontaneous structure formation process of CNF. For example, even if the added component has a particle size larger than CNF, the added component can be incorporated into the fiber network during the agglomeration and entanglement process of CNF during drying, forming a structure that envelops the added component from the outside. In one embodiment, when an added component is embedded in CNF, this refers to a state in which the CNF is aggregated so as to cover part or all of the surface of the added component.

[0036] Selective control of redispersibility: Unlike conventional technologies that aim for complete nano-level dispersion of CNF, this invention allows for partial and selective design of redispersibility, thereby achieving both retention and controlled release of functional ingredients. This approach of actively using "difficulty in redispersion" as a design factor is not seen in conventional CNF applications and is a unique technology.

[0037] "The preferred example of the cellulose-based material used in the present invention is cellulose nanofiber (CNF), but fine cellulose (e.g., microfibrillated cellulose (MFC), finely ground plant-derived dietary fiber, etc.) that exhibits a similar physical embedding effect can also be used. Furthermore, in the present invention, taking into consideration redispersibility, embedding ability, and sustained release, the above-mentioned fine cellulose can be used in combination with or instead of the above-mentioned material.

[0038] The component-embedded dried product of the present invention can be used for the following purposes, and the additive component can be an appropriate component depending on the purpose. Cosmetic applications: The ingredient-embedded dried product is characterized in that the added ingredients are cosmetic ingredients such as moisturizing, anti-inflammatory, UV protection, skin conditioning, coloring, and fragrance for skin or hair. Food applications: A dried product embedded with an ingredient, wherein the added ingredient is a food ingredient such as a flavoring, sweetener, seasoning, nutrient, lactic acid bacteria, enzyme, or vitamin. Sanitary treatment agent applications: A component-embedded dried body for daily use, characterized in that the added component is a deodorizer, deodorant, fragrance, antibacterial agent, antifungal agent, or cleaning auxiliary component. Agricultural use: The added ingredients are fertilizer or pesticide ingredients such as urea, phosphoric acid, potassium, etc., and are slowly released in a moist soil environment. Medical use: The ingredient-embedded dried body is characterized in that the added ingredient is an active ingredient contained in a pharmaceutical or quasi-drug product, and is used for applications that allow application to the skin or mucous membranes or transdermal absorption. Dispersibility and stability: When redispersed in a liquid medium, the CNF is uniformly dispersed and the functionality of the added ingredients is maintained.

[0039] The ingredient-embedded dried material according to the present invention has excellent structural properties, redispersibility, and sustained release properties, and can be put to practical use in a wide variety of product forms, such as those listed below. Cosmetic applications: Embedding fragrances, moisturizing ingredients, UV absorbers, etc. into this dried product allows for stable retention on the skin surface and delayed release. This allows for long-lasting fragrance, extended moisturizing effects, and the gradual delivery of UV protection to the skin, achieving both functionality and comfort. It is expected to be used in a wide range of formulations, including creams, lotions, sheet masks, and BB creams. Food applications: Functional ingredients such as food flavorings, vitamins, amino acids, and lactic acid bacteria are embedded in the dried product and provided in the form of soup stock sheets, supplements, seasonings, etc. This allows the flavor of the ingredients to be maintained and the release of the ingredients is delayed in the gastrointestinal tract. This not only improves stability during processing and heating, but is also expected to improve the flavor and nutrient absorption efficiency when consumed. Daily use: By using this dried product in fabric mists, air fresheners, fabric softeners, deodorizers, antibacterial agents, etc., it is possible to sustain the effects of sustained release on clothing and indoor spaces. It is expected to be particularly effective in maintaining the scent even after washing and in maintaining deodorizing and antibacterial functions for a long period of time. Agricultural applications: By embedding fertilizer ingredients such as urea, phosphate, and potassium, or pesticide ingredients, and slowly releasing them in the soil, it is possible to efficiently and continuously supply the ingredients necessary for plant growth. This technology also contributes to reducing the environmental impact by reducing the frequency of fertilization and pest control, and preventing groundwater pollution. Medical uses: By applying it to compresses, liniments, transdermal patches, or oral powders for skin and mucous membranes, the sustained action of the medicinal ingredients can be achieved. Taking advantage of the stability and dispersibility of the dried form, it is possible to easily design formulations by mixing it with water or a base just before use. Printing and coating fields: By dispersing this dried substance in inks, coatings, and films, it becomes possible to produce printed matter and packaging materials with functions such as fragrance, antibacterial properties, anti-fogging properties, and coloring. In particular, it is expected to be developed into high-value-added products that take advantage of its sustained release properties. Textile applications: When applied to textiles such as clothing, underwear, towels, and curtains, by carrying a dried material containing fabric softeners, fragrances, antibacterial agents, etc. on the textile, the functional ingredients are gradually released during washing and wearing. Such functional fibers can be used in fields such as clothing, hygiene, nursing care, and medicine.

[0040] From the viewpoint of transportation and storage efficiency, the ingredient-embedded dried material of the present invention can be prepared by mixing one or more functional ingredients with CNF, drying, and processing it into a sheet, powder, or other form, which can then be molded, transported, and provided. As a final product, it is not necessary to redisperse the functional ingredients, and it is possible to gradually release the functional ingredients by mixing with moisture or sweat on the skin, a moisturizer or lotion, or by heating or rehydrating food.

[0041] The present invention will be described below using specific examples, but the present invention is not limited to the following embodiments. [Example]

[0042] (Preparation of CNF) After bleaching the shredded lettuce, the shredded lettuce was treated with NaOH for 1 hour, and then stirred for 5 minutes in a high-speed rotating blade mixer (estimated rotation speed: 9,000-11,000 rpm), repeated five times. The resulting CNF gel was used in the following examples. AFM measurements of the CNFs in the resulting CNF gel confirmed the presence of fibrous structures with a diameter of approximately 5 nm. This invention targets nanofibers with a diameter of 100 nm or less, and the results of this measurement are an example within that range. Example 1 Put 1000 ml of water into a pot and bring to a boil. Add 30 g of bonito flakes and let sit for 1-2 minutes. Place a colander over a bowl, place kitchen paper (or cloth) on the colander, and slowly strain the bonito flakes. Let sit for 1 minute to collect the broth. Mix 5-10 g of 1% CNF gel with 100 ml of the resulting broth. Stir for 5 minutes using a blender or similar. Transfer to a container so that the mixture is about 5 mm thick and dry naturally for 6-12 hours or heat to 50°C for 3-5 hours (freeze drying, vacuum drying, low-temperature spray drying, etc. are also possible). Store in sheet or powder form in a dry place.

[0043] Depending on the application, it can be added to water or hot water and redispersed using a mixer or high-speed shearing machine. In addition, the sheet form can be sprinkled on top as is, or wrapped around rice balls like nori seaweed, which softens the surface with the moisture from the rice and creates an adhesive bond, preventing the surface of the rice ball from drying out.

[0044] Furthermore, by mixing finely chopped dried CNF dashi sheets or powder into cooked rice, the rice's overall moisture retention can be improved, making it less likely to dry out even when cooled.

[0045] By adding ingredients and rolling, baking, or boiling it, it can be used as a wrapper for dumplings or spring rolls, or as an edible film material with seasoning properties.

[0046] Example 2 A CNF dispersion containing fragrance (synthetic fragrances including rose, jasmine, lavender, and cherry blossom) was applied to a film-molding sheet and dried, and the fragrance was observed to evaporate and diffuse with a time lag after drying from the resulting CNF sheet.

[0047] (Example 3: Hair straightening treatment using CNF) Unmodified cellulose nanofibers (CNF) were dispersed in water, and hydrolyzed keratin and ceramide were added. The pH of the resulting mixture was adjusted to a weak acidity (approximately 5.5). After applying the first agent for the straightening treatment, the hair was rinsed with water, sprayed with the mixture, and then treated with a dry iron. The hair was then treated with the second agent.

[0048] It is believed that the CNFs locally aggregated and settled inside the hair during ironing, retaining the hydrolyzed keratin and ceramides inside. This resulted in an improvement in the appearance and feel of the finished hair.

[0049] (Example 4: Perm treatment with CNF) Unmodified cellulose nanofiber (CNF) was dispersed in water, and hydrolyzed keratin and ceramide were added. The pH of the mixture was adjusted to approximately 5.5. After applying the first agent of perm treatment and rinsing with water, the mixture was sprayed on and left to warm. Then, treatment with the second agent was performed.

[0050] It is believed that the CNFs locally aggregated and fixed inside the hair during heating, retaining the added ingredients inside the hair. This treatment tended to improve the texture and flexibility of the permed hair.

[0051] (Example 5: Color treatment with CNF) Unmodified cellulose nanofiber (CNF) was dispersed in water, and hydrolyzed keratin and ceramide were added. The pH of the resulting mixture was adjusted to approximately 5.5, and after the hair color application and leaving process was completed, it was sprayed onto the hair. The hair was then left to stand (heating with a hair dryer or heater was also possible), and before rinsing off the color, a small amount of lukewarm water was applied and massaged in to emulsify, followed by rinsing with water and shampooing.

[0052] It was suggested that CNF locally aggregated and fixed inside the hair, retaining hydrolyzed keratin and ceramide, resulting in improved moisture retention, softness, and shine in hair after color treatment.

[0053] Examples 3 to 5 suggest that under conditions of temperature change or moisture loss, CNF may locally aggregate and adhere to hair, preserving components such as hydrolyzed keratin and ceramide. This effect is due to the "propensity of CNF to form a microcapsule-like structure and retain and slowly release ingredients."

Claims

1. A method for producing a powder or gel of a component-embedded dried body, comprising the steps of: mixing a cellulose nanofiber (CNF) gel with an added component in an aqueous medium; and drying the mixture to obtain a powder or gel of the component-embedded dried body in which the added component is physically embedded within the aggregated structure of the CNF gel.

2. The manufacturing method described in claim 1, characterized in that the CNF is unmodified CNF obtained by mechanical fiberization.

3. 2. The method according to claim 1, wherein the additive component is an oily component dispersed in an aqueous medium in combination with a surfactant.

4. The manufacturing method described in claim 1, characterized in that the CNF is CNF that has been chemically modified by one of TEMPO oxidation, phosphate esterification, carboxymethylation, or cationization.

5. a step of redispersing the powder or gel obtained by the manufacturing method according to any one of claims 1 to 4 in an aqueous medium; producing fibers using the redispersed powder or gel; A method for producing a fiber, comprising:

6. The manufacturing method according to claim 5, The method for producing a fiber, wherein the fiber is at least one fiber selected from the group consisting of clothing fibers, underwear fibers, towel fibers, curtain fibers, and medical fibers.

7. a step of redispersing the powder or gel obtained by the manufacturing method according to any one of claims 1 to 4 in an aqueous medium; producing a food or beverage product using the redispersed powder or gel; A method for producing a food or beverage, comprising:

8. a step of redispersing the powder or gel obtained by the manufacturing method according to any one of claims 1 to 4 in an aqueous medium; a step of producing a sanitary treatment agent using the redispersed powder or gel; A method for producing a sanitary treatment agent, comprising:

9. The manufacturing method according to claim 8, The method for producing a sanitary treatment agent, wherein the sanitary treatment agent is at least one sanitary treatment agent selected from the group consisting of fabric mists, fragrances, fabric softeners, deodorizers, and antibacterial agents.

10. a step of redispersing the powder or gel obtained by the manufacturing method according to any one of claims 1 to 4 in an aqueous medium; producing a pesticide using the redispersed powder or gel; A method for producing a pesticide, comprising:

11. a step of redispersing the powder or gel obtained by the manufacturing method according to any one of claims 1 to 4 in an aqueous medium; producing a fertilizer using the redispersed powder or gel; A method for producing a fertilizer, comprising:

12. a step of redispersing the powder or gel obtained by the manufacturing method according to any one of claims 1 to 4 in an aqueous medium; preparing a medical composition using the redispersed powder or gel; A method for producing a medical composition, comprising:

13. a step of redispersing the powder or gel obtained by the manufacturing method according to any one of claims 1 to 4 in an aqueous medium; preparing a printing composition using the redispersed powder or gel; A method for producing a printing composition, comprising:

14. The method of claim 13, The method for producing a printing composition, wherein the printing composition is an ink.

15. a step of redispersing the powder or gel obtained by the manufacturing method according to any one of claims 1 to 4 in an aqueous medium; preparing a coating composition using the redispersed powder or gel; A method for producing a coating composition, comprising:

16. The method of claim 15, The method for producing a coating composition, wherein the coating composition is a coating agent or a coating film.