Method for producing polysaccharide-containing particles, precursor polysaccharide-containing particles, and polysaccharide-containing particles

Abstract

According to the present invention, provided is a method for producing polysaccharide-containing particles, the method comprising a spray-drying step in which precursor polysaccharide-containing particles are obtained by spray-drying a dispersion liquid containing a polysaccharide in a salt form, and a desalination step in which the precursor polysaccharide-containing particles are obtained by spray-drying a dispersion liquid containing a polysaccharide in a salt form. The polysaccharide in the form of a salt contained in the precursor polysaccharide-containing particles is brought into contact with a desalting agent, and the polysaccharide in the form of a salt is desalted by the desalting agent to obtain polysaccharide-containing particles.

Description

[Technical field]

[0001] The present invention relates to a method for producing polysaccharide-containing particles, precursor polysaccharide-containing particles, and polysaccharide-containing particles. [Background Technology]

[0002] In the past, particles containing polysaccharides have been widely used as additives for cosmetics, pharmaceuticals, foods, coatings, etc. For example, Patent Document 1 discloses a method for producing microparticles, characterized in that an aqueous solution containing a water-soluble polysaccharide and a reactive resin or a water-soluble crosslinking agent is spray-dried and granulated, and the obtained particles are heat-treated to crosslink and become insoluble in water. In addition, Patent Document 2 discloses a method for producing particles containing polysaccharides, which includes: a spray-drying step of spray-drying a solution containing polysaccharides and polyols to obtain a precursor; and a heating step of heating the precursor obtained in the aforementioned spray-drying step to obtain particles containing polysaccharides. [Prior art documents] [Patent Document]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 8-27277 [Patent Document 2] Japanese Patent Application Publication No. 2022-94097 [Summary of the invention] [Problems to be solved by the invention]

[0004] The above-mentioned prior arts all utilize crosslinking agents to react polysaccharides with crosslinking agents, thereby insolubilizing particles containing polysaccharides, and the obtained particles contain crosslinking agents and crosslinked structures. In recent years, many industries, including the cosmetics industry, have been required to use materials that are non-toxic to the ecosystem and highly biodegradable, or to reduce the use of organic solvents. From the perspective of accompanying chemical reactions and the perspective that the decomposability of the obtained particles may deteriorate, the technology of crosslinking water-soluble polysaccharides to make them insoluble is sometimes unacceptable. In addition, the insolubilization treatment sometimes requires a long-term heating treatment at a high temperature, and there may be a case where the particles containing polysaccharides are colored.

[0005] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for producing polysaccharide-containing particles using a desalting agent. [Technical solutions to solve the problem]

[0006] According to the present invention, there is provided a method for producing particles containing polysaccharides. It includes a spray drying step and a desalting step. In the spray drying step, the dispersion containing the polysaccharide in salt form is spray dried to obtain particles containing the precursor polysaccharide. In the desalting step, the polysaccharide in salt form contained in the precursor polysaccharide-containing particles is brought into contact with a desalting agent, and the polysaccharide in salt form is desalted by the desalting agent to obtain polysaccharide-containing particles.

[0007] As a result of diligent research, the inventors have discovered that particles containing polysaccharides that are not easily soluble in water and have little color can be obtained by a specific manufacturing method, thereby completing the present invention. The specific manufacturing method includes: a spray drying step, spray drying a dispersion containing polysaccharides in salt form to obtain particles containing precursor polysaccharides; and a desalting step, contacting the aforementioned polysaccharide in salt form with a desalting agent, and using the aforementioned desalting agent to desalt the aforementioned polysaccharide in salt form to obtain particles containing polysaccharides.

[0008] Various embodiments of the present invention are described below. The embodiments described below can be combined with each other. [1] A method for producing particles containing polysaccharides, comprising a spray drying step and a desalting step, wherein in the spray drying step, a dispersion containing polysaccharides in salt form is spray dried to obtain particles containing precursor polysaccharides, and in the desalting step, the polysaccharides in salt form contained in the particles containing precursor polysaccharides are brought into contact with a desalting agent, and the polysaccharides in salt form are desalted using the desalting agent to obtain particles containing polysaccharides. [2] A manufacturing method as described in [1], wherein the desalting step includes a heating treatment step, in which the particles containing the precursor polysaccharide are heated while the polysaccharide in salt form is in contact with a desalting agent, and the polysaccharide in salt form is desalted using the desalting agent to obtain particles containing the polysaccharide. [3] The production method according to [1], wherein the dispersion further contains inorganic particles. [4] The production method according to any one of [1] to [3], wherein the desalting agent is a nitrogen-containing compound, a carboxylic acid or an alcohol. [5] The production method according to [4], wherein the nitrogen-containing compound is at least one selected from the group consisting of urea, amine, amide, and nitrogen-containing heterocyclic compounds. [6] The production method according to any one of [1] to [5], wherein the polysaccharide is at least one selected from the group consisting of chitosan, cellulose, and derivatives thereof. [7] A production method as described in any one of [1] to [6], wherein when the polysaccharide-containing particles are immersed in water, the color difference ΔE of the solid component is 0 to 60, and the color difference ΔE is a value relative to a reference white in the L*a*b* color space. [8] The production method according to [2], wherein in the heat treatment step, the heat treatment is performed at a temperature of 100°C or higher and lower than 200°C. [9] A precursor polysaccharide-containing particle, comprising a polysaccharide in a salt form and a desalting agent capable of desalting the polysaccharide in a salt form.

[10] A polysaccharide-containing particle, comprising a polysaccharide and a neutralizing agent, wherein the neutralizing agent can neutralize an acid or a base that can form a salt with the polysaccharide.

[11] The polysaccharide-containing particles according to

[10] , wherein the solubility of the particles when immersed in water at 25°C for 7 days is 50% by mass or less.

[12] The polysaccharide-containing particles according to

[10] or

[11] , further comprising inorganic particles. [Effects of the invention]

[0009] According to the method for producing polysaccharide-containing particles of the present invention, by using a desalting agent to desalt a polysaccharide in salt form, it is possible to obtain polysaccharide-containing particles that are not easily soluble in water and have little coloration. Furthermore, the obtained polysaccharide-containing particles can be used for various purposes such as external preparations for cosmetics, additives for coatings, additives for pharmaceuticals, additives for resin compositions, film additives for imparting optical or anti-adhesion properties, and parts for steps such as calcination or grinding, etc., by utilizing their characteristics, and can be particularly used for cosmetics. [Specific implementation method]

[0010] Hereinafter, the present invention will be described in detail by illustrating the embodiments of the present invention. The present invention is not limited by these descriptions. The various characteristic matters of the embodiments of the present invention shown below can be combined with each other. In addition, each characteristic matter independently constitutes an invention.

[0011] 1. Method for producing polysaccharide-containing particles The method for producing polysaccharide-containing particles of the present invention comprises a spray drying step and a desalting step, and optionally comprises a heating treatment step. In the spray drying step, a dispersion containing polysaccharides in salt form is spray dried to obtain particles containing precursor polysaccharides, and in the desalting step, the polysaccharides in salt form contained in the precursor polysaccharide-containing particles are contacted with a desalting agent, and the polysaccharides in salt form are desalted by the desalting agent to obtain particles containing polysaccharides.

[0012] In the production method of the present invention, the polysaccharide in salt form is brought into contact with the desalting agent. In the production method of the present invention, the desalting agent may be added in any step as long as the polysaccharide in salt form is brought into contact with the desalting agent in the desalting step. The desalting agent may also be added in the dispersion preparation step, for example. In this case, in the dispersion preparation step, a dispersion containing a polysaccharide in salt form and a desalting agent is prepared, and the dispersion is spray-dried to obtain precursor polysaccharide-containing particles containing a polysaccharide in salt form and a desalting agent. In this case, the desalting step preferably includes a heating treatment step. When the desalting agent is prepared in the dispersion, it is preferred to appropriately select the types of the polysaccharide in salt form and the desalting agent. As an example, it is preferred to select a combination that is difficult to desalt at room temperature. For example, the desalting agent may be added after obtaining the precursor polysaccharide-containing particles in the spray drying step (in this case, the precursor polysaccharide-containing particles may not contain the desalting agent). In this case, the desalting agent may be added by immersing the obtained precursor polysaccharide-containing particles in a solution containing the desalting agent, or spraying and / or coating the solution containing the desalting agent, or exposing the particles to a gas containing the desalting agent, so that the polysaccharide in salt form may be in contact with the desalting agent. In one embodiment of the present invention, after obtaining the particles containing the precursor polysaccharide by the spray drying step, the particles are contacted with a desalting agent. At this time, a heat treatment step may be performed or not. In one embodiment of the present invention, water resistance can be improved even if a heat treatment step is not performed afterwards. From the viewpoint of suppressing coloration, it is preferred that a heating step is not performed after contacting with a desalting agent. When there is no heat treatment step, it is preferred to appropriately select the types of polysaccharides in salt form and the desalting agent. As an example, a combination of desalting at room temperature is preferably selected. The production method according to one embodiment of the present invention preferably includes at least one of the above-mentioned methods of adding a desalting agent. In the production method according to one embodiment of the present invention, it is preferred that the particles containing the precursor polysaccharide are contacted with the desalting agent after being obtained by the spray drying step.

[0013] 1.1 Dispersion preparation steps The method for producing polysaccharide-containing particles according to one embodiment of the present invention may include a dispersion preparation step. In the dispersion preparation step, a dispersion containing a polysaccharide in salt form is prepared. The dispersion contains a polysaccharide in salt form, and when a desalting agent is further added in the dispersion preparation step, the dispersion may also contain a desalting agent. In addition, the dispersion may also contain inorganic particles.

[0014] As the solvent of the dispersion liquid, water, an organic solvent, or a mixed solvent of water and an organic solvent can be listed, wherein preferably water is contained, and water is more preferably contained. Water, for example, natural water, purified water, distilled water, ion exchange water, pure water, etc. can be listed, wherein ion exchange water is preferred. As the organic solvent, for example, aliphatic monohydric alcohols such as methanol, ethanol, isopropanol, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, aromatic compounds such as toluene, xylene, etc. can be listed, and for example, a mixed solvent of water and an organic solvent can also be listed. In addition, the solvent may contain an alcohol having a carbon number of 3 or more, or may not contain an alcohol.

[0015] 1.1.1 Polysaccharides in salt form The dispersion contains a polysaccharide in salt form. The dispersion can be obtained by adding a polysaccharide in salt form, i.e., a polysaccharide salt, to a solvent, or by adding a polysaccharide and a salt-forming agent to a solvent. The polysaccharide in salt form can be one compound. The polysaccharide in salt form can also contain two or more compounds.

[0016] Polysaccharides include glucosamine series and molecules containing glucose units. Glucosamine series include chitosan as β-1,4-glucosamine. In addition, chitin as β-1,4-N-acetylglucosamine can be listed. Molecules containing glucose units include β-glucans. β-glucans include β-1,4-glucans and β-1,3-glucans. As β-1,4-glucans, cellulose, cellulose acetate, ethyl cellulose, methyl cellulose, carboxymethyl cellulose, carboxyethyl cellulose, hydroxyethyl cellulose, and hydroxypropyl methyl cellulose can be listed. As β-1,3-glucans, curdlan and paramylon can be listed. In addition, alginic acid as a block polymer of β-D-mannuronic acid and α-L-guluronic acid can be listed. Their derivatives can also be listed. The polysaccharide is preferably at least one selected from the group consisting of chitosan, cellulose, and their derivatives.

[0017] The polysaccharide salts may include salts of the above-mentioned polysaccharides, and the salt-forming agent may include an acid or base that can make the used polysaccharide form a salt state. As one example, when the polysaccharide is chitosan, an acid may be used as the salt-forming agent. The acid may include organic acids such as carboxylic acids, and inorganic acids such as hydrochloric acid and sulfuric acid. The carboxylic acids may include carboxylic acids listed below as desalting agents. As another example, when the polysaccharide is carboxymethyl cellulose, an alkali may be used as the salt-forming agent. The alkali may include inorganic bases such as nitrogen-containing compounds, aluminum hydroxide, and potassium hydroxide. The nitrogen-containing compounds may include nitrogen-containing compounds listed below as desalting agents.

[0018] The polysaccharide in salt form is preferably soluble in water. The solubility of the polysaccharide in salt form may be higher than that of the desalted polysaccharide contained in the polysaccharide-containing particles described later. Specifically, the solubility of the polysaccharide in salt form when immersed in water at 25° C. for 7 days may be 80% by mass or more. The solubility of the polysaccharide in salt form when immersed in water at 25° C. for 7 days is, for example, 80, 85, 90, 95, 96, 97, 98, 99, 100% by mass, and may also be within the range between any two of the values ​​exemplified here.

[0019] 1.1.2 Desalting Agent When a desalting agent is added in the dispersion preparation step, the dispersion may contain a desalting agent, and the desalting agent is not particularly limited as long as it is a compound that neutralizes an acid or a base (a salt-forming agent that forms a salt with a polysaccharide) and performs desalting or a compound that promotes desalting. The desalting agent may include a substance that does not have a desalting function under normal temperature and atmospheric pressure, and exerts a desalting function when heated, applied with energy such as light, etc. The desalting agent may be a base, an acid, or an alcohol, and may be a base, an acid, or an alcohol with more than 3 carbon atoms. As a desalting agent that exerts a desalting function by heating, applying energy such as light, photo (thermal) base generators and photo (thermal) acid generators can be listed, and as an example, a curing agent for epoxy resin can be listed. When the salt-forming agent is an acid, the desalting agent can be a base, and when the salt-forming agent is a base, the desalting agent can be an acid. In addition, the mechanism by which alcohol functions as a desalting agent is not fully understood, but it is speculated that one of the reasons is that the addition of alcohol changes the crystal structure. The desalting agent may be a nitrogen-containing compound, a carboxylic acid, or an alcohol, or may be a nitrogen-containing compound, a carboxylic acid, or a monohydric alcohol, or may be a nitrogen-containing compound, a carboxylic acid, or a monohydric alcohol having a carbon number of 3 or more. When the heat treatment step described later is performed, the desalting agent is more preferably a heat-resistant substance that remains in the obtained polysaccharide-containing particles.

[0020] The nitrogen-containing compound may be at least one selected from the group consisting of urea, amine, amide, and nitrogen-containing heterocyclic compounds. Urea may include urea and urea derivatives. Specifically, urea, methyl urea, ethyl urea, propyl urea, butyl urea, isobutyl urea, 1,1-dimethyl urea, 1,3-dimethyl urea, 1,1-diethyl urea, 1,3-diethyl urea, tetramethyl urea, 1,1,3,3-tetraethyl urea, 1,1,3,3-tetrabutyl urea, etc. may be mentioned. Among them, urea and tetramethyl urea are particularly preferred from the viewpoint of desalination effect. Examples of amines include compounds having an amine structure, such as ammonia, methylamine, ethylamine, n-propylamine, n-butylamine, n-pentylamine, n-hexylamine and other alkylamines, methanolamine, triethanolamine, diethanolamine, monoethanolamine, propanolamine, isopropanolamine, diisopropanolamine and other alkanolamines, ethylenediamine, putrescine, cadaverine, hexamethylenediamine, polyethylenediamine and other polyamines. Examples of amides include compounds having a structure obtained by dehydration condensation of ammonia, a primary amine or a secondary amine with an oxygen-containing acid, such as nicotinamide, acetanilide, acetamide, ε-caprolactam, γ-butyrolactam. Examples of the nitrogen-containing heterocyclic compound include pyridine, nicotinic acid, 2-methylpyridine, 3-methylpyridine, 4-methylpyridine, 2-hydroxy-4-methylpyridine, 2-hydroxy-6-methylpyridine, 2-hydroxypyridine, 3-hydroxypyridine, and 4-hydroxypyridine; pyrrolidines such as 1-methylpyrrolidine, 1-ethylpyrrolidine, 1-(2-hydroxyethyl)pyrrolidine, and 2-(2-hydroxyethyl)-1-methylpyrrolidine; piperidines such as 1-methylpiperidine, 1-ethylpiperidine, 1-(2-hydroxyethyl)piperidine, 1-(hydroxymethyl)piperidine, 3-hydroxy-1-methylpiperidine, 4-hydroxy-1-methylpiperidine, and 1,4-dimethylpiperidine; piperazines such as 1-methylpiperazine and 1-ethylpiperazine; natural extracts having a nitrogen-containing heterocyclic ring; and nucleic acids such as purine bases and pyrimidine bases. Nicotinic acid is particularly preferred from the viewpoint of the desalting effect. From the viewpoint of desalination effect, the nitrogen-containing compound preferably contains one or more selected from polyethylenediamine, ammonia, urea, tetramethylurea, and nicotinic acid. The pH value of the desalting agent, especially the nitrogen-containing compound, is preferably 7 or more, for example, 7, 8, 9, 10, 11, 12, 13, 14, and may also be in the range between any two of the values ​​exemplified here. The nitrogen-containing compound is preferably a strongly alkaline compound, more preferably polyethylenediamine and ammonia.

[0021] Examples of the carboxylic acid include saturated fatty acids such as formic acid, acetic acid, propionic acid, and butyric acid; hydroxy acids such as lactic acid, malic acid, and citric acid; and dicarboxylic acids such as oxalic acid, succinic acid, and adipic acid.

[0022] As alcohol, monohydric alcohols such as 1-propanol, isopropanol, and 1-butanol, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, trihydric alcohols such as glycerol, diglycerol, erythritol, trimethylolethane, trimethylolpropane, pentaerythritol, dipentaerythritol, sorbitol, etc. can be listed. From the viewpoint of desalination effect, monohydric alcohols are preferred, and isopropanol is more preferred. Methanol and ethanol have poor desalination effects, so they are not preferred. Alcohols sometimes cannot obtain sufficient desalination effects due to heat volatilization during spray drying, so it is preferred to contact the particles containing precursor polysaccharides with the desalting agent after obtaining them in the spray drying step. Desalting agents other than urea can improve water resistance by contacting the particles containing the precursor polysaccharide with the desalting agent after obtaining them in the spray drying step, and the subsequent heating step is optional. When urea is used as the desalting agent, the heating step is preferably performed. When a desalting agent is added to the dispersion and spray-dried, the boiling point of the desalting agent is preferably 70° C. or higher. In this case, the boiling point of the desalting agent is, for example, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, or 200° C., or may be within a range between any two of the values ​​exemplified herein. When the particles containing the precursor polysaccharide are contacted with a desalting agent after being obtained in the spray drying step, a desalting agent with low water solubility may be used. When the particles containing the precursor polysaccharide are contacted with a desalting agent after being obtained in the spray drying step, the desalting agent is more preferably polyethylenediamine, ammonia, isopropanol, an alkali metal salt aqueous solution, an alkaline earth metal aqueous solution, tetrahydroxypropylethylenediamine, a tertiary amine such as dimethylaminoethanol, and a primary amine such as 1-amino-3-undecyoxypropane.

[0023] 1.1.3 Inorganic particles The dispersion may also contain inorganic particles. Examples of the inorganic particles include titanium oxide, zirconium oxide, zinc oxide, cerium oxide, magnesium oxide, barium sulfate, calcium sulfate, magnesium sulfate, calcium carbonate, magnesium carbonate, talc, mica, kaolin, sericite, muscovite, synthetic mica, phlogopite, red mica, biotite, lepidolite, silicic acid, silicic anhydride, aluminum silicate, magnesium silicate, magnesium aluminum silicate, calcium silicate, barium silicate, strontium silicate, metal tungstate, hydroxyapatite, vermiculite, commercially available products of aluminum hydroxide (Higilite), bentonite, montmorillonite, hectorite, zeolite, dicalcium phosphate, aluminum oxide, aluminum hydroxide, boron nitride, silicon dioxide, and the like. The inorganic particles are preferably in the shape of plates or scales, and more preferably are mica. The mica may be natural mica or synthetic mica.

[0024] The average particle size of the inorganic particles can be 5 to 100 μm, for example, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100 μm, or in the range between any two of the values ​​exemplified herein. In addition, the average particle size can be the volume average diameter measured using a laser diffraction scattering method. The aspect ratio of the inorganic particles can be 20 to 200, for example, 20, 40, 60, 80, 100, 120, 140, 160, 180, 200, or in the range between any two of the values ​​exemplified herein. In addition, the aspect ratio can be the major diameter / thickness of the inorganic particles.

[0025] 1.1.4 Content of each component in the dispersion The dispersion may contain 0.05 to 35% by mass of a polysaccharide in the form of a salt. The concentration of the polysaccharide salt in the dispersion is, for example, 0.05, 0.1, 0.5, 1, 5, 0, 5, 10, 15, 20, 25, 30, 35% by mass, or in the range between any two of the numerical values ​​exemplified herein. In addition, when a polysaccharide and a salt-forming agent are added to a solvent to obtain a dispersion, 1 to 300 parts by mass of the salt-forming agent may be added relative to 100 parts by mass of the polysaccharide. The content of the salt-forming agent is, for example, 0, 50, 100, 150, 200, 250, 300 parts by mass relative to 100 parts by mass of the polysaccharide, or in the range between any two of the numerical values ​​exemplified herein.

[0026] When the dispersion contains a desalting agent, the content of the desalting agent may be 0.1 to 10.0 mass %. The concentration of the desalting agent in the dispersion is, for example, 0.1, 0.2, 0.3, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5, 10.0 mass %, and may be in the range between any two of the numerical values ​​exemplified here. The dispersion preferably contains more than 1 mass part of the desalting agent relative to 100 mass parts of the polysaccharide in the salt form. The content of the desalting agent is, for example, 1, 2, 3, 5, 10, 15, 20, 25, 30 mass parts relative to 100 mass parts of the polysaccharide in the salt form in the dispersion, and may be in the range between any two of the numerical values ​​exemplified here. In addition, the desalting agent has the function of promoting the desalting of polysaccharides in salt form. From the viewpoint that it preferably remains in the polysaccharide-containing particles as a neutralizing agent, it is preferred to add an excess amount of the desalting agent so that some of it remains after the manufacturing step of one embodiment of the present invention, and when the heat treatment step is performed, some of it remains after the heat treatment step.

[0027] When the dispersion contains inorganic particles (e.g., mica), the concentration of the inorganic particles in the dispersion may be 0.1 to 70% by mass. The concentration of the inorganic particles may be, for example, 0.1, 0.5, 1, 5, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 60, 70% by mass, or any two of the values ​​exemplified herein. The dispersion preferably contains more than 10 parts by mass of polysaccharides in the form of salts relative to 100 parts by mass of the inorganic particles. The content of the polysaccharide in the form of salt is, for example, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 110, 120, 130, 140, 150, 200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, 1100, 1150, 1200 parts by mass relative to 100 parts by mass of the inorganic particles in the dispersion, or may be in the range between any two of the numerical values ​​exemplified here. By adjusting the type and amount of the inorganic particles and the polysaccharide in the form of salt in the dispersion, the structure and physical properties of the obtained polysaccharide-containing particles can be adjusted. For example, by making the concentration of the polysaccharide in the form of salt in the dispersion sufficiently high, and by making the content of the polysaccharide in the form of salt relative to the inorganic particles sufficiently high, it is possible to obtain particles containing polysaccharides that include inorganic particles that are fully coated with a coating layer containing polysaccharides. As another example, in particular, when the inorganic particles are plate-like particles or flaky particles such as mica, it is possible to obtain particles containing polysaccharides as composite particles, in which a sufficient number and size of spherical particles containing polysaccharides are attached to the surface of the inorganic particles or the coating layer. Inorganic particles that are fully coated with a coating layer, and composite particles in which a sufficient number and size of spherical particles containing polysaccharides are attached to the surface of the inorganic particles or the coating layer, can constitute a powder with a low average friction coefficient and a high soft focus coefficient.

[0028] The dispersion may contain known components within a range that does not impair the effects of the present invention. Examples of known components include components that may be contained in the precursor polysaccharide-containing particles described later.

[0029] The viscosity of the dispersion is preferably 1 Pa·s or less. By achieving such a viscosity, particles containing polysaccharides having an appropriate shape and / or structure can be obtained. In the dispersion preparation step, treatments for adjusting the viscosity and rheology of the dispersion may be performed as necessary. For example, treatments for reducing the viscosity, especially the dynamic viscosity under high shear force, and treatments for imparting pseudoplasticity and thixotropy may be cited. As an example, these treatments may be performed by adding a dispersant or reducing the molecular weight of an organic material.

[0030] The dispersion can be prepared by stirring with a known stirrer, for example, a dispersing mixer, a homomixer, a high-pressure homogenizer, etc. can be used.

[0031] The mixing order in the dispersion preparation step is not particularly limited. As an example, when the dispersion contains a polysaccharide in salt form and a desalting agent, a polysaccharide salt (or a polysaccharide and a salt-forming agent) may be added and mixed in a solvent to first prepare a dispersion containing the polysaccharide in salt form, and then the desalting agent may be added. By mixing in this order, precipitation of the polysaccharide can be prevented.

[0032] 1.2 Spray drying step In the spray drying step, the dispersion containing the polysaccharide in salt form is spray dried to obtain precursor polysaccharide-containing particles. The precursor polysaccharide-containing particles of the present invention contain the polysaccharide in salt form, and may contain a desalting agent capable of desalting the polysaccharide in salt form, and may also contain inorganic particles.

[0033] In the spray drying step, the dispersion is supplied to a spray dryer (spray dryer) adjusted to a predetermined temperature and sprayed to obtain particles containing the precursor polysaccharide. The spray dryer is not particularly limited as long as it is a spray dryer commonly used in granulation production. The spray dryer may include: ·Raw material tank for storing dispersion liquid, ·Raw material supply pump for supplying dispersion liquid, Nozzles (four-fluid nozzles, two-fluid nozzles or single-fluid nozzles) or rotating disks that make the dispersion into fine droplets, Drying chamber for drying and granulating the droplets, Blowers, filters, heaters, and A collector for recovering the composite powder precursor by a two-point collection method, a cyclone method, a bag filtration method, etc. (these collectors may also be heatable collectors), etc. By adjusting the droplet formation conditions and drying conditions in the spray drying step, the shape, structure and physical properties of the obtained precursor polysaccharide-containing particles can be adjusted.

[0034] In the spray drying step, the outlet temperature of the spray dryer may be 70 to 250° C. The outlet temperature may be, for example, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250° C., or may be within the range between any two of the values ​​exemplified herein. In addition, when the dispersion contains a desalting agent, a portion of the salt-form polysaccharide in the obtained precursor polysaccharide-containing particles may be desalted by the desalting agent in the spray drying step. That is, the spray drying step can also serve as the desalting step described later. In addition, in the spray drying step, for example, by adjusting the drying conditions after granulation, further providing a heating function in the spray dryer, or a heating chamber that can heat and maintain a certain time, it can also serve as the heat treatment step described later.

[0035] 3.3 Desalting step In the desalting step, the polysaccharide in salt form contained in the precursor polysaccharide-containing particles is brought into contact with a desalting agent, and the polysaccharide in salt form is desalted by the desalting agent to obtain polysaccharide-containing particles. The desalting step may be heated and may include the following heat treatment steps.

[0036] In general, there are known methods for improving water resistance by forming a cross-linked structure using a cross-linking agent, and methods for improving water resistance by modifying the entire material or the surface of the material. However, these methods are sometimes not accepted because they are accompanied by chemical reactions or may make the decomposability of the obtained particles worse. In the present invention, by contacting the polysaccharide in salt form with a desalting agent in the heat treatment step, the polysaccharide in salt form is desalted by the desalting agent, and the crystallinity of the polysaccharide is improved, so that water resistance can be improved (reducing solubility). It is speculated that according to the present invention, by contacting with a desalting agent, the desalting and / or crystallinity improvement of the polysaccharide in salt form is promoted, and it is easy to form a firm state in which the polysaccharide molecules are more tightly hydrogen-bonded to each other, thereby improving water resistance. According to one embodiment of the present invention, the material can be prevented from yellowing due to heating. In addition, compared with the case where the desalting agent is not prepared, the water resistance can be improved without heating treatment, or by heating treatment at a lower temperature and / or for a shorter time, so the material can be prevented from yellowing.

[0037] As mentioned above, in the manufacturing method of the present invention, as long as the state in which the polysaccharide in salt form is in contact with the desalting agent can be formed, the desalting agent can be added in any step, and can also be added after the particles containing the precursor polysaccharide are obtained in the spray drying step. The manufacturing method of one embodiment of the present invention may include a desalting agent adding step before the heat treatment step and / or in the heat treatment step. At this time, in the desalting agent adding step, for example, the obtained particles containing the precursor polysaccharide can be immersed in a solution containing the desalting agent, or sprayed and / or coated with a solution containing the desalting agent, or exposed to a gas containing the desalting agent to add the desalting agent and form a state in which the polysaccharide in salt form is in contact with the desalting agent. As the desalting agent, the desalting agents listed in the dispersion preparation step can be listed. In addition, when preparing a solution containing a desalting agent, the solution may contain 0.1 to 90.0% by mass of the desalting agent. The concentration of the desalting agent in the solution is, for example, 0.1, 0.2, 0.3, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5, 10.0, 20.0, 30.0, 40.0, 50.0, 60.0, 70.0, 80.0, 90.0 mass %, and may be in the range between any two of the values ​​exemplified here. The amount of the desalting agent added is preferably 10 mass parts or more, more preferably 40 mass parts or more, and most preferably 100 mass parts or more relative to 100 mass parts of the salt form of the polysaccharide-containing particles. The upper limit is preferably 400 mass parts or less, more preferably less than 200 mass parts, and most preferably 180 mass parts or less. The content of the desalting agent is, for example, 1, 2, 3, 5, 10, 15, 20, 25, 30, 50, 100, 200, 300, or 400 parts by mass relative to 100 parts by mass of the salt form of the precursor polysaccharide-containing particles, or may be within the range between any two of the values ​​exemplified herein. The upper limit is preferably 400 parts by mass or less, more preferably less than 200 parts by mass, and most preferably 180 parts by mass or less. In addition, when the desalting agent contains an alkali (or acid), the amount of the alkali (or acid) in the solution containing the desalting agent in contact with 100 parts by mass of the salt form of the polysaccharide contained in the particles containing the precursor polysaccharide can be 1 to 150 parts by mass, for example, 1, 2, 3, 5, 10, 15, 20, 25, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, or 150 parts by mass, or can be within the range between any two of the values ​​exemplified here.

[0038] As described above, the desalting step may include a heating treatment step, in which the particles containing the precursor polysaccharide are heated while the polysaccharide in salt form is in contact with a desalting agent, and the polysaccharide in salt form is desalted using the desalting agent to obtain particles containing the polysaccharide.

[0039] In the heat treatment step, the heat treatment is preferably performed at 100°C or higher and lower than 200°C. The heat treatment temperature is, for example, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, 180, 185, 190, 195° C., or less than 200° C., or may be in the range between any two of the numerical values ​​exemplified herein. The heat treatment time is, for example, 1, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, or 300 minutes, or may be in the range between any two of the numerical values ​​exemplified herein. As an example, the heat treatment can be performed under the following condition A. A 100℃ or higher and lower than 150℃, more than 20 minutes The heating temperature of condition A may be 100° C. or higher and lower than 150° C., for example, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145° C., or lower than 150° C., or may be in the range between any two of the numerical values ​​exemplified herein. The heating time of condition A may be 20 minutes or higher, for example, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300 minutes, or may be in the range between any two of the numerical values ​​exemplified herein. As another example, the heat treatment may be performed under the following condition B. B 150℃ or higher but lower than 200℃, 1 minute or higher but lower than 90 minutes The heating temperature of condition B may be 150° C. or more and less than 200° C., for example, 150, 155, 160, 165, 170, 175, 180, 185, 190, 195° C., less than 200° C., or in the range between any two of the numerical values ​​exemplified herein. The heating time of condition B may be 1 minute or more and less than 90 minutes, for example, 1, 2, 3, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85 minutes, less than 90 minutes, or in the range between any two of the numerical values ​​exemplified herein. By heating at low temperature for a long time or at high temperature for a short time, yellowing and coloring of the precursor polysaccharide-containing particles can be prevented. The heat treatment conditions are preferably a temperature and time that makes the color difference ΔE of the solid component of the obtained polysaccharide-containing particles when immersed in water become 0 to 60, and the color difference ΔE of the solid component of the obtained polysaccharide-containing particles when immersed in water is, for example, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, preferably a temperature and time that makes the color difference ΔE of the solid component of the obtained polysaccharide-containing particles when immersed in water become a range between any two of the values ​​exemplified here.

[0040] The production method of one embodiment of the present invention may include a washing step after the desalting step. In the washing step, the excess desalting agent may be removed by dehydration washing. The desalting step may not be performed, and the desalting agent may remain after the desalting step.

[0041] Hereinafter, the precursor polysaccharide-containing particles and the polysaccharide-containing particles of the present invention will be described. The precursor polysaccharide-containing particles can be obtained by spray-drying a dispersion containing the polysaccharide in salt form (and a desalting agent, if necessary) in the aforementioned spray-drying step.

[0042] 2. Particles containing precursor polysaccharides The precursor polysaccharide-containing particles of the present invention contain a polysaccharide in salt form. The precursor polysaccharide-containing particles of one embodiment of the present invention contain a polysaccharide in salt form and a desalting agent capable of desalting the polysaccharide in salt form. When the precursor polysaccharide-containing particles of one embodiment of the present invention contain a desalting agent, the desalting agent can be used to desalt a portion of the polysaccharide in salt form in the precursor polysaccharide-containing particles, that is, the particles may contain desalted polysaccharides. Examples of the polysaccharide in salt form, the desalting agent, and the polysaccharide include the polysaccharides in salt form, the desalting agent, and the polysaccharide listed in the description of the dispersion preparation step of the method for producing the polysaccharide-containing particles.

[0043] When the precursor polysaccharide-containing particles contain a desalting agent, it is preferred that 0.1 parts by mass or more of the desalting agent be contained relative to 100 parts by mass of the total of the salt form of the polysaccharide and the polysaccharide in the precursor polysaccharide-containing particles. The content of the desalting agent relative to 100 parts by mass of the salt form of the polysaccharide in the dispersion is, for example, 0.1, 0.2, 0.3, 0.5, 1, 2, 3, 5, 10, 15, 20, 25, 30 parts by mass, and may be within the range between any two of the values ​​exemplified here.

[0044] The particles containing the precursor polysaccharide may be spherical particles. Spherical particles also include slightly spherical particles, and are intended to mean particles having a round shape. The maximum diameter / minimum diameter of the spherical particles is preferably 0.5 to 1.5, and more preferably 0.8 to 1.2. In addition, spherical particles may also include partially broken or cut spherical shapes such as hemispherical (lens-shaped, etc.) particles, but preferably at least half of the particles contain particles whose maximum diameter / minimum diameter is within the above numerical range. In addition, the spherical particles may be particles with a concave surface, few wrinkles, and smooth surface.

[0045] The average particle size of the spherical particles may be less than 10 μm. The average particle size may be 0.1 to 10 μm, for example, 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 μm, or may be in the range between any two of the values ​​exemplified herein. In addition, the average particle size of the spherical particles may be measured by SEM observation. The average particle size may be obtained by measuring the particle size of the spherical particles one by one and taking the average value thereof.

[0046] The precursor polysaccharide-containing particles may further contain inorganic particles. Examples of the inorganic particles include those listed in the description of the dispersion preparation step in the method for producing the polysaccharide-containing particles.

[0047] When the precursor polysaccharide-containing particles contain inorganic particles (eg, mica), the precursor polysaccharide-containing particles preferably contain 10 parts by mass or more in total of the polysaccharide in the form of a salt and the polysaccharide, relative to 100 parts by mass of the inorganic particles. The total content of the polysaccharide in the form of a salt and the polysaccharide relative to 100 parts by mass of the inorganic particles in the dispersion is, for example, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 110, 120, 130, 140, 150, 200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, 1100, 1150, or 1200 parts by mass, or may be within a range between any two of the numerical values ​​exemplified here.

[0048] When the precursor polysaccharide-containing particles contain inorganic particles, the precursor polysaccharide-containing particles may be composite particles containing inorganic particles, a coating layer, and spherical particles. Here, the coating layer may cover the inorganic particles. The spherical particles may be attached to the inorganic particles or the coating layer covering the inorganic particles. In addition, the coating layer and the spherical particles contain polysaccharides in salt form, and may contain a desalting agent capable of desalting the polysaccharides in salt form, or may contain desalted polysaccharides.

[0049] By adjusting the inorganic particles in the precursor polysaccharide-containing particles, and the types and amounts of salt-form polysaccharides and polysaccharides, the structure and physical properties of the obtained polysaccharide-containing particles can be adjusted. For example, by making the concentration of salt-form polysaccharides and polysaccharides in the precursor polysaccharide-containing particles sufficiently high, and by making the content of salt-form polysaccharides and polysaccharides sufficiently high relative to the inorganic particles, it is possible to obtain precursor polysaccharide-containing particles containing inorganic particles fully coated with a coating layer containing salt-form polysaccharides and polysaccharides. Based on the precursor polysaccharide-containing particles, polysaccharide-containing particles that can constitute a powder with a high soft focus factor can be obtained. As another example, in particular, when the inorganic particles are plate-like particles or flaky particles such as mica, precursor polysaccharide-containing particles can be obtained as composite particles, in which a sufficient number and size of spherical particles containing precursor polysaccharides are attached to the surface of the inorganic particles or the coating layer. According to the precursor polysaccharide-containing particles, polysaccharide-containing particles capable of constituting a powder having a low average friction coefficient and a high soft focus coefficient can be obtained.

[0050] When the particles containing precursor polysaccharides contain inorganic particles, the inorganic particles are at least partially coated by the coating layer, and preferably the inorganic particles are coated by the coating layer as a whole. As mentioned above, the coating layer contains polysaccharides in salt form, and may contain a desalting agent that can desalt the polysaccharides in salt form, or may contain desalted polysaccharides. The situation that the inorganic particles are coated by the coating layer can be confirmed by SEM observation, EDS (energy dispersive X-ray analysis), and dissolving the coating layer that coats the inorganic particles again to confirm its quality. According to the particles containing precursor polysaccharides of the present invention, after a heat treatment step, particles containing polysaccharides containing inorganic particles coated by the coating layer containing polysaccharides can be obtained. Such particles containing polysaccharides can constitute a powder with excellent soft focus property because its inorganic particles are coated by the coating layer.

[0051] When the particles containing precursor polysaccharides contain inorganic particles, at least one spherical particle may be attached to the inorganic particles and / or the coating layer in the particles containing precursor polysaccharides. For example, when the inorganic particles are plate-like or flaky particles such as mica, it is preferred that at least one spherical particle is attached to the two main surfaces of the inorganic particles directly or via the coating layer. Hereinafter, the particles attached to the inorganic particles refer to the particles attached to the inorganic particles directly or via the coating layer. The number of spherical particles attached to an inorganic particle is, for example, 1, 2, 3, 5, 9, 10, 15, 20, 15, 30, 31, 40, 50, 60, 70, 80, 90, 100, or it may be within the range between any two of the numerical values ​​exemplified herein. The presence or absence of spherical particles attached to the inorganic particles and the number of spherical particles attached to an inorganic particle can be confirmed by observing the particles containing polysaccharides using SEM. Furthermore, part of the spherical particles may not be attached to the inorganic particles, and the precursor polysaccharide-containing particles including inorganic particles according to one embodiment of the present invention may include spherical particles that are not attached to the inorganic particles.

[0052] The precursor polysaccharide-containing particles of one embodiment of the present invention may contain a total of 50 parts by mass or more of polysaccharides, polysaccharides, and salt-forming agents (and inorganic particles as needed) in the form of salts, relative to 100 parts by mass of the precursor polysaccharide-containing particles, for example, 50, 60, 70, 80, 90, 100 parts by mass, or within the range between any two of the values ​​exemplified herein. The precursor polysaccharide-containing particles of one embodiment of the present invention may also be composed of polysaccharides, polysaccharides, and salt-forming agents (and inorganic particles as needed) in the form of salts.

[0053] The precursor polysaccharide-containing particles of one embodiment of the present invention may contain known ingredients used in polysaccharide-containing particles, such as known ingredients used in cosmetics, within the range that does not impair the effects of the present invention. Examples of known ingredients include organic powders, oily ingredients, surfactants, ultraviolet absorbers, moisturizers, anti-fading agents, antioxidants, defoamers, preservatives, fragrances, solubilizers, plasticizers, viscosity modifiers, skin-beautifying ingredients (whitening agents, cell activators, rough skin improvers, blood circulation promoters, skin astringents, anti-seborrheic agents, etc.), vitamins, amino acids, antiperspirants, alcohols, film-forming agents, anti-inflammatory agents, cooling agents, nucleic acids, hormones, inclusion compounds, pH adjusters, chelating agents, etc.

[0054] 3. Particles containing polysaccharides By contacting a polysaccharide in salt form with a desalting agent and desalting the polysaccharide in salt form with the desalting agent, particles containing polysaccharides can be obtained. The particles containing polysaccharides of the present invention contain polysaccharides and a neutralizing agent. Here, a neutralizing agent refers to a substance that can neutralize an acid or alkali that can form a salt with a polysaccharide. The neutralizing agent may be a desalting agent contained in the particles containing the precursor polysaccharide and remaining in the particles containing polysaccharides after the desalting step and the heat treatment step. The particles containing polysaccharides may also contain polysaccharides in salt form that are not desalted in the desalting step and the heat treatment step, but from the viewpoint of improving water resistance, it is preferred that the content of polysaccharides in salt form is low. The content of polysaccharides in salt form can be confirmed by the evaluation of solubility described later. The particles containing polysaccharides may also not contain polysaccharides in salt form. As polysaccharides and polysaccharides in salt form, polysaccharides and polysaccharides in salt form listed in the description of the dispersion preparation step of the method for producing particles containing polysaccharides can be listed. Examples of the neutralizing agent include the desalting agents listed in the description of the dispersion preparation step in the method for producing polysaccharide-containing particles.

[0055] In addition, the solubility of the desalted polysaccharide when immersed in water at 25° C. for 7 days is preferably less than 80% by mass. The solubility of the desalted polysaccharide when immersed in water at 25° C. for 7 days is, for example, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75% by mass, less than 80% by mass, and may be within the range between any two of the values ​​exemplified here.

[0056] The polysaccharide-containing particles preferably contain 0.01 parts by mass or more of the desalting agent relative to 100 parts by mass of the total of the polysaccharide and the polysaccharide in the form of a salt in the polysaccharide-containing particles. The content of the desalting agent relative to 100 parts by mass of the polysaccharide in the form of a salt in the dispersion is, for example, 0.01, 0.02, 0.03, 0.05, 0.1, 0.2, 0.3, 0.5, 1, 2, 3, 5, 10, 15, 20, 25, 30 parts by mass, and may be within the range between any two of the numerical values ​​exemplified here.

[0057] The polysaccharide-containing particles can be obtained by desalting the polysaccharide in salt form using a desalting agent, and the shape and average particle size thereof can be the same as those of the precursor polysaccharide-containing particles.

[0058] The polysaccharide-containing particles may further contain inorganic particles. Examples of the inorganic particles include those listed in the explanation of the dispersion preparation step in the method for producing the polysaccharide-containing particles.

[0059] When the polysaccharide-containing particles contain inorganic particles (eg, mica), the polysaccharide-containing particles preferably contain 10 parts by mass or more of the polysaccharide and the polysaccharide in the form of a salt in total per 100 parts by mass of the inorganic particles. The total content of the polysaccharide and the polysaccharide in the form of a salt is, for example, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 110, 120, 130, 140, 150, 200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, 1100, 1150, or 1200 parts by mass relative to 100 parts by mass of the inorganic particles in the dispersion, or may be within a range between any two of the numerical values ​​exemplified here.

[0060] When the polysaccharide-containing particles contain inorganic particles, the polysaccharide-containing particles may be composite particles containing inorganic particles, a coating layer, and spherical particles. Here, the coating layer may cover the inorganic particles. The spherical particles may be attached to the inorganic particles or the coating layer covering the inorganic particles. In addition, the coating layer and the spherical particles contain polysaccharides and a neutralizing agent that can neutralize an acid or base that can form a salt with the polysaccharide, and may also contain polysaccharides in the form of salts.

[0061] By adjusting the inorganic particles in the polysaccharide-containing particles, and the types and amounts of polysaccharides and polysaccharides in the form of salts, the structure and physical properties of the polysaccharide-containing particles can be adjusted. For example, by making the concentration of polysaccharides and polysaccharides in the form of salts in the polysaccharide-containing particles sufficiently high, and by making the content of polysaccharides and polysaccharides in the form of salts sufficiently high relative to the inorganic particles, it is possible to obtain polysaccharide-containing particles comprising inorganic particles fully coated with a coating layer containing polysaccharides and polysaccharides in the form of salts. Based on the polysaccharide-containing particles, a powder with a high soft focus coefficient can be formed. As another example, in particular, when the inorganic particles are plate-like particles or flaky particles such as mica, polysaccharide-containing particles as composite particles can be obtained, in which a sufficient number and size of spherical particles containing polysaccharides are attached to the surface of the inorganic particles or the coating layer. Based on the polysaccharide-containing particles, a powder with a low average friction coefficient and a high soft focus coefficient can be formed.

[0062] When the particles containing polysaccharides contain inorganic particles, the inorganic particles are at least partially coated with a coating layer, and preferably the inorganic particles are entirely coated with a coating layer. As mentioned above, the coating layer contains polysaccharides and a neutralizing agent that can neutralize an acid or base that can form a salt with the polysaccharides, and may also contain polysaccharides in the form of salts. The situation in which the inorganic particles are coated with a coating layer can be confirmed by SEM observation, EDS (energy dispersive X-ray analysis), separation of the particles containing precursor polysaccharides and re-dissolving the coating layer that coats the inorganic particles to confirm its mass, etc. The particles containing polysaccharides of the present invention can constitute a powder with excellent soft focus properties because the inorganic particles are coated with a coating layer.

[0063] When the particles containing polysaccharides contain inorganic particles, at least one spherical particle may be attached to the inorganic particles and / or the coating layer in the particles containing polysaccharides. For example, when the inorganic particles are plate-like or flaky particles such as mica, it is preferred that at least one spherical particle is attached to the two main surfaces of the inorganic particles directly or via a coating layer. Hereinafter, particles attached to inorganic particles refer to particles attached to inorganic particles directly or via a coating layer. The number of spherical particles attached to an inorganic particle is, for example, 1, 2, 3, 5, 9, 10, 15, 20, 15, 30, 31, 40, 50, 60, 70, 80, 90, 100, or within the range between any two of the numerical values ​​exemplified herein. The presence or absence of spherical particles attached to inorganic particles and the number of spherical particles attached to an inorganic particle can be confirmed by observing the particles containing polysaccharides using SEM. Furthermore, part of the spherical particles may not be attached to the inorganic particles, and the polysaccharide-containing particles including inorganic particles according to one embodiment of the present invention may include spherical particles that are not attached to the inorganic particles.

[0064] The polysaccharide-containing particles of one embodiment of the present invention may contain a total of 50 parts by mass or more of polysaccharides, polysaccharides in salt form, and neutralizers (and inorganic particles as needed), for example, 50, 60, 70, 80, 90, 100 parts by mass, or within the range between any two of the values ​​exemplified herein, relative to 100 parts by mass of the polysaccharide-containing particles. The polysaccharide-containing particles of one embodiment of the present invention may be composed of polysaccharides, polysaccharides in salt form, and neutralizers (and inorganic particles as needed).

[0065] The polysaccharide-containing particles of one embodiment of the present invention may contain known components used in polysaccharide-containing particles, for example, known components used in cosmetics, within the range that does not impair the effects of the present invention. As known components, the components listed as known components that can be contained in precursor polysaccharide-containing particles can be cited.

[0066] 3.1 Physical properties of polysaccharide-containing particles The polysaccharide-containing particles of one embodiment of the present invention preferably have a solubility of 50% by mass or less, and more preferably 30% by mass or less, when immersed in water at 25° C. for 7 days, from the viewpoint of water resistance for use as a cosmetic powder. For example, it may be 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, or 50% by mass, or may be in the range between any two of the values ​​exemplified herein. The solubility of the composite powder when immersed in water at 25° C. for 7 days can be calculated by immersing the polysaccharide-containing particles in ion-exchanged water at 25° C. for 7 days, and using the mass Ag of the polysaccharide-containing particles before immersion and the mass Bg of the residue after immersion according to the following formula. [Solubility (mass %)] = (AB) / A×100 The solubility of the polysaccharide-containing particles can be controlled by adjusting the type and amount of the polysaccharide and the production conditions of the polysaccharide-containing particles (type and amount of the salt form of the polysaccharide and the desalting agent formulated in the dispersion, and the heating treatment temperature and time). Here, when the polysaccharide-containing particles contain inorganic particles, it is more preferred that the solubility of the residue (component containing the polysaccharide and the neutralizer) after removing the inorganic particles from the polysaccharide-containing particles is within the above range.

[0067] The polysaccharide-containing particles according to one embodiment of the present invention preferably do not undergo gelation or swelling when 1 g of the polysaccharide-containing particles is immersed in 10 times the amount of ion-exchanged water at 25° C. for 7 days. In addition, the solubility of the polysaccharide-containing particles is preferably lower than that of the precursor polysaccharide-containing particles before the desalting step. The difference between the solubility of the polysaccharide-containing particles when immersed in water at 25° C. for 7 days and the solubility of the precursor polysaccharide-containing particles when immersed in water at 25° C. for 7 days is, for example, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95% by mass, and may also be within the range between any two of the values ​​exemplified herein.

[0068] The polysaccharide-containing particles of one embodiment of the present invention preferably have a solid component color difference ΔE of 0 to 60 when the polysaccharide-containing particles are immersed in water. When the color difference ΔE is in the aforementioned range, yellowing and coloring are suppressed, and thus it can be used as an external preparation for cosmetics and an additive for coatings. ΔE can be a value relative to the reference white in the L*a*b* color space. The color difference ΔE is, for example, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, or can be within the range between any two of the values ​​exemplified herein. The color difference ΔE of the solid component when the polysaccharide-containing particles are immersed in water can be controlled by adjusting the type and amount of the polysaccharide, and the manufacturing conditions when the polysaccharide-containing particles are manufactured (the type and amount of the salt-form polysaccharide and the desalting agent prepared in the dispersion, and the heating treatment temperature and time), especially the heating treatment temperature and time.

[0069] The polysaccharide-containing particles are preferably biodegradable. Biodegradability means that the polymer decomposes and disappears in the earth environment such as soil and seawater, and / or decomposes and disappears in the body. As an example, the polysaccharide-containing particles preferably have a BOD decomposition degree of 60% or more when exposed to activated sludge for 28 days based on OECDTG301C. As another example, the polysaccharide-containing particles preferably have a decomposition degree of 60% or more when buried in soil based on JIS K 6955 (ISO17556), or a relative decomposition degree of 90% or more relative to cellulose. As another example, the polysaccharide-containing particles preferably have a relative decomposition degree of 60% or more relative to cellulose when left standing in seawater and sandy deposits based on ISO19679. However, when the polysaccharide-containing particles contain inorganic particles, it is preferred that the biodegradability of the residue (components containing polysaccharides and neutralizers) after removing the inorganic particles from the polysaccharide-containing particles is within the above range.

[0070] The polysaccharide-containing particles of one embodiment of the present invention, especially when containing inorganic particles, may have a soft focus factor (SFF) of 0.86 or more, and may be 0.86 to 1.40. The soft focus factor is, for example, 0.86, 0.90, 0.95, 1.00, 1.05, 1.10, 1.15, 1.20, 1.25, 1.3, 1.35, 1.40, or may be within the range between any two of the values ​​exemplified here. The soft focus factor can be measured by coating the polysaccharide-containing particles on a skin material such as artificial skin and using a variable angle photometer. The light source can be fixed at 45°, and the sensor can be scanned from 0° to 180° to measure the brightness at each angle, and the ratio of the brightness at the two points (brightness at 65° / brightness at 135°) is used as the soft focus factor. By making the soft focus factor above the above lower limit, a cosmetic with suppressed glare perception can be obtained. By making the soft focus factor equal to or greater than the above lower limit, the high brightness of inorganic particles such as mica as extender pigments can be fully utilized to obtain cosmetics with brightness. The soft focus factor can be adjusted by the type and structure of the components of the particles containing polysaccharides. In particular, it can be adjusted by controlling the amount of the coating layer on the inorganic particles such as mica, and the number and size of the spherical particles.

[0071] The particles containing polysaccharides according to one embodiment of the present invention, especially when containing inorganic particles, may have an average friction coefficient (MIU) of 0.75 or less, and may be 0.40 to 0.75. The average friction coefficient is, for example, 0.40, 0.45, 0.50, 0.55, 0.60, 0.65, 0.70, 0.75, or may be in the range between any two of the values ​​exemplified herein. The average friction coefficient can be obtained by coating the particles containing polysaccharides on skin materials such as artificial skin and scanning using a friction tester. Specifically, it can be measured using the method described in the examples. By making the average friction coefficient above the above lower limit, the uniform state of the cosmetic powder can be maintained after being applied to the skin, and cosmetics with excellent so-called cosmetic durability can be obtained. In addition, there is little collapse or falling off during or after molding by compression, and the moldability is excellent. If the average friction coefficient is below the above upper limit, a smooth, non-rough, uniformly coated cosmetic can be obtained. The average friction coefficient can be adjusted by the type and structure of the components of the polysaccharide-containing particles, and in particular, by controlling the number and size of spherical particles attached to inorganic particles such as mica.

[0072] The polysaccharide-containing particles according to one embodiment of the present invention preferably have a porosity of 50% or less, for example, 0, 10, 20, 30, 40, 50%, or may be in the range between any two of the values ​​exemplified herein. The polysaccharide-containing particles according to one embodiment of the present invention may not include porous particles.

[0073] The polysaccharide-containing particles according to one embodiment of the present invention can obtain polysaccharide-containing particles that are not easily soluble in water and have little coloration by using a desalting agent to desalt the polysaccharide in salt form. According to one embodiment of the present invention, polysaccharide-containing particles that do not contain a cross-linking agent and a cross-linking structure can be obtained. According to one embodiment of the present invention, polysaccharide-containing particles that are non-toxic to the ecosystem, have high biodegradability, and use less organic solvents can be obtained, thereby meeting the industry demand for manufacturing more environmentally friendly products. The polysaccharide-containing particles of the present invention have the above-mentioned properties, are not easily soluble in water, and have little coloration. Therefore, utilizing these properties, they can be used in various applications such as external preparations for cosmetics, additives for coatings, additives for pharmaceuticals, additives for resin compositions, additives for films for imparting optical or anti-adhesion properties, and components for steps such as calcination or grinding, and are particularly useful in cosmetics.

[0074] Examples of the cosmetics include liquid, gel, solid and the like cosmetics, and examples thereof include foundation, powder, eye shadow, eyeliner, eyebrow pencil, blusher, lipstick, and nail polish. The polysaccharide-containing particles comprising inorganic particles according to one embodiment of the present invention include inorganic particles fully coated with a coating layer containing polysaccharides and polysaccharides in salt form, and can be composite particles in which a sufficient number and size of spherical particles containing sugars are attached to the surface of the inorganic particles or the coating layer. Based on the polysaccharide-containing particles, a powder with a low average friction coefficient and a high soft focus coefficient can be obtained, that is, a cosmetic with excellent smoothness and soft focus properties can be obtained. [Example]

[0075] Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

[0076] (Example 1) <Dispersion Preparation Step> Chitosan (KOYO Chitosan FL-80, manufactured by Koyo Chemical Co., Ltd.) and acetic acid were added and mixed in water. Urea was further added to the obtained aqueous solution to prepare a dispersion containing a polysaccharide in the form of a salt with a chitosan concentration of 5% by mass, an acetic acid concentration of 5% by mass, and 0.5% by mass of urea, and a desalting agent.

[0077] <Spray Drying Step> Using a two-fluid nozzle laboratory spray dryer, the inlet temperature of the spray dryer was set to 200°C, and spray drying was performed to obtain the precursor polysaccharide-containing particles 1 containing the desalting agent. When the inlet temperature of the spray dryer was set to 200°C, the outlet temperature was 70 to 120°C.

[0078] <Heat treatment step> The obtained precursor polysaccharide-containing particles 1 containing a desalting agent were heated at 120° C. for 240 minutes in an atmospheric environment to obtain polysaccharide-containing particles 1 .

[0079] The shape of the obtained polysaccharide-containing particles 1 was observed by SEM, and it was confirmed that spherical particles with a particle size of 0.1 to 10 μm were formed.

[0080] (Examples 2 to 18, Comparative Examples 1 to 8) The conditions for preparing the dispersion and the heat treatment were changed as described in Tables 1 to 3 to obtain polysaccharide-containing particles 2 to 18.

[0081] (Example 19) <Dispersion Preparation Step> Mica (average particle size 20 μm), chitosan (manufactured by Koyo Chemical Co., Ltd., KOYO Chitosan FL-80) and acetic acid were added and mixed in water. Urea was further added to the obtained aqueous solution to prepare a dispersion having a mica concentration of 5% by mass, a chitosan concentration of 5% by mass, an acetic acid concentration of 5% by mass and a urea concentration of 0.5% by mass.

[0082] The spray drying step and the heat treatment step were carried out in the same manner as in Example 1 to obtain polysaccharide-containing particles 19.

[0083] The shape of the polysaccharide-containing particles 19 obtained by SEM observation confirmed that the mica was coated with polysaccharides, and 10 to 30 spherical polysaccharide-containing particles with a particle size of 0.1 to 10 μm were attached to one mica particle. In addition, the average friction coefficient (MIU) was evaluated by the method described below, and the result was 0.54. In addition, the soft focus factor (SFF) was measured by the method described below, and the result was 1.05.

[0084] (Example 20) <Dispersion Preparation Step> Chitosan (manufactured by Koyo Chemical Co., Ltd., KOYO Chitosan FL-80) and acetic acid were added to water and mixed to prepare a dispersion 20 containing no desalting agent and having a chitosan concentration of 5% by mass and an acetic acid concentration of 5% by mass.

[0085] <Spray Drying Step> Using a two-fluid nozzle laboratory spray dryer, the inlet temperature of the spray dryer was set to 200°C, and spray drying was performed to obtain the precursor polysaccharide-containing particles 1 containing the desalting agent. When the inlet temperature of the spray dryer was set to 200°C, the outlet temperature was 70 to 120°C.

[0086] <Desalting Step> Mix 10 g of a 30% aqueous solution of ammonia (containing 3 g of ammonia) as a nitrogen-containing compound, 6 g of water, and 2 g of methanol to prepare a solution containing a desalting agent. Add 5 g of the obtained particles containing precursor polysaccharides to an alcohol aqueous solution mixed with 5 g of water and 5 g of methanol and stir. While maintaining the dispersed state by stirring, slowly add the above-mentioned solution containing the desalting agent. After adding the desalting agent solution, stir for 3 hours, then filter with suction through a sieve, wash the obtained filter cake with 100 g of tap water and filter with suction. After fully removing the water by suction filtration, dry in a dryer at 50°C for 5 hours to obtain particles 20 containing polysaccharides. The above operations are all carried out at room temperature (23°C).

[0087] (Examples 21 to 27) Polysaccharide-containing particles 21 to 27 were obtained in the same manner as in Example 20 except that the dispersant formulation and the type of nitrogen-containing compound were changed as described in Table 4. The amount of each desalting agent in the desalting step in Table 4 represents 5 parts by mass relative to the precursor polysaccharide-containing particles.

[0088] (Example 28) <Dispersion Preparation Step and Spray Drying Step> A dispersion 28 was obtained in the same manner as in Example 1 except that the dispersion preparation was changed as described in Table 4. Furthermore, a spray drying step was carried out in the same manner as in Example 1 to obtain particles 28 containing a precursor polysaccharide.

[0089] <Desalting Step> Add 5 g of the obtained precursor polysaccharide-containing particles to an alcohol-water solution prepared by mixing 5 g of water and 10 g of isopropanol and stir. While maintaining the dispersed state by stirring, slowly add the above-mentioned solution containing the desalting agent. After adding the desalting agent solution, stir for 3 hours, then perform suction filtration using a sieve, wash the obtained filter cake with 100 g of tap water and perform suction filtration. After fully removing the moisture by suction filtration, dry in a dryer at 50°C for 5 hours to obtain polysaccharide-containing particles 28. The above operations are all performed at room temperature (23°C).

[0090] <Examples 29 and 30> Polysaccharide-containing particles 29 and 30 were obtained in the same manner as in Example 28 except that methanol or ethanol was used instead of isopropanol and the type and amount of the desalting agent used in the desalting step were changed as described in Table 4.

[0091] The raw materials used in the preparation of the dispersion are as follows. Natural mica: average particle size 20μm Chitosan: KOYO Chitosan FL-80, manufactured by Koyo Chemical Co., Ltd., deacetylation degree 75% or more CMC-NH 4 (Ammonium carboxymethyl cellulose): Nichirin Chemical Industries, Ltd., KICCOLATENA-3L

[0092] (Evaluation of polysaccharide-containing particles) <Color difference (ΔE) from reference white when particles are immersed in water> The obtained polysaccharide-containing particles were immersed in ion exchange water, and the color tone of the solid content was measured in the L*a*b* color space using Color Reader CR-13 (manufactured by Konica Minolta), and the color difference ΔE from the reference white (L=100, a=b=0) was calculated and evaluated according to the following evaluation criteria. The results are shown in Tables 1 to 4.

[0093] <Solubility> 1 g of polysaccharide-containing particles was immersed in 10 times the mass of ion exchange water at 25°C for 7 days, and then the mixture was filtered by suction using a glass fiber filter. The residue captured on the filter was dried in a dryer at 100°C for 2 hours, and the mass of the residue was calculated. The mass of the sample before immersion was defined as Ag and the mass of the residue was defined as Bg. The solubility of each sample was calculated by the following formula and evaluated according to the following evaluation criteria. The results are shown in Tables 1 to 4. [Solubility (mass %)] = (AB) / A×100 〇: 30% or less △: More than 30% and less than 50% ×: more than 50%

[0094] <State of particles immersed in water> 1 g of the polysaccharide-containing particles was immersed in 10 times the amount of ion-exchanged water at 25° C. for 7 days, and the state thereof was observed. ×: Polysaccharide-containing particles absorb water and / or dissolve in water and are in a gelled state △: The polysaccharide-containing particles settle in the water. The particles absorb at least part of the water and swell, increasing in volume. ○: The polysaccharide-containing particles settled in the water, and no swelling of the particles was observed.

[0095] <Average Friction Coefficient (MIU)> The obtained polysaccharide-containing particles 19 were concentrated to 1 mg / cm 2 The film was applied on artificial skin (Beaulax), and the friction coefficient was measured using a friction tester KES with a load of 50 N and a scanning speed of 1 mm / s for 30 mm. The average value of the central 20 mm was taken as the average friction coefficient (MIU).

[0096] <Soft Focus Factor (SFF)> The obtained polysaccharide-containing particles 19 were concentrated to 10 mg / cm 2 The soft focus coefficient was evaluated by applying the composite powder on artificial skin (Beaulax) using a variable angle photometer (GC-5000L manufactured by Nippon Denshoku Industries Co., Ltd.). Specifically, the light source was fixed at a 45° position, and the sensor was scanned from 0° to 180° on the surface of the artificial skin coated with the composite powder, and the brightness at each angle was measured, and the ratio of the brightness at two points (brightness at 65° / brightness at 135°) was used as the soft focus coefficient.

[0097] [Table 1]

[0098] [Table 2]

[0099] [Table 3]

[0100] [Table 4]

Claims

1. A method for producing particles containing polysaccharides, It includes a spray drying step and a desalting step. In the spray drying step, the dispersion containing the polysaccharide in salt form is spray dried to obtain particles containing the precursor polysaccharide. In the desalting step, a desalting agent is brought into contact with the polysaccharide in salt form contained in the precursor polysaccharide-containing particles, and the polysaccharide in salt form is desalted by the desalting agent to obtain polysaccharide-containing particles.

2. The manufacturing method according to claim 1, in, The desalination step includes a heating step, In the heat treatment step, the precursor polysaccharide-containing particles are heated while the polysaccharide in salt form is in contact with a desalting agent, and the polysaccharide in salt form is desalted by the desalting agent to obtain polysaccharide-containing particles.

3. The manufacturing method according to claim 1, in, The dispersion further contains inorganic particles.

4. The manufacturing method according to claim 1 or 2, in, The desalting agent is a nitrogen-containing compound, a carboxylic acid or an alcohol.

5. The manufacturing method according to claim 4, in, The nitrogen-containing compound is at least one selected from the group consisting of urea, amine, amide, and nitrogen-containing heterocyclic compounds.

6. The manufacturing method according to claim 1 or 2, in, The polysaccharide is at least one selected from the group consisting of chitosan, cellulose and derivatives thereof.

7. The manufacturing method according to claim 1 or 2, in, When the polysaccharide-containing particles are immersed in water, the color difference ΔE of the solid content is 0 to 60, The color difference ΔE is a value relative to a reference white in the L*a*b* color space.

8. The manufacturing method according to claim 2, in, In the heat treatment step, the heat treatment is performed at 100° C. or higher and lower than 200° C.

9. A precursor polysaccharide-containing particle, comprising a polysaccharide in a salt form and a desalting agent capable of desalting the polysaccharide in a salt form.

10. A polysaccharide-containing particle, comprising a polysaccharide and a neutralizing agent, The neutralizing agent can neutralize the acid or base that can form a salt with the polysaccharide.

11. The polysaccharide-containing particles according to claim 10, in, The solubility when immersed in water at 25°C for 7 days was 50% by mass or less. 12 . The polysaccharide-containing particles according to claim 10 , further comprising inorganic particles.

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