JP2009242518A - Composite polyamide porous fine particle having moisture retention, and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composite polyamide porous fine particles having both features of a polyamide porous fine particles and a moisture retention compound by an industrially easy method. <P>SOLUTION: In the composite polyamide porous fine particles, the moisture retention compound is carried on the outer surfaces or/and inner parts of the pores of the polyamide porous fine particles having 1 to 30 μm number average particle diameter, a ratio (PDI) of a volume average particle diameter to the number average particle diameter of 1.0 to 2.0, 0.01 to 0.5 μm average pore diameter, 0.1 to 80 m<SP>2</SP>/g BET specific surface area and porosity (RI) of 5 to 100. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention has a specific particle size and a narrow particle size distribution, and is moisturized on the outer peripheral surface or / and internal pores of polyamide porous fine particles having a specific BET specific surface area, average pore size, and porosity (RI). The present invention relates to composite fine particles carrying a functional compound.

  Many fine particles having moisturizing properties are used in the fields of cosmetics and quasi drugs.

  For example, as fine particles having moisturizing properties, those in which a moisturizing component such as polyhydric alcohol is adsorbed on spherical silica (see Patent Document 1), and resin fine particles in which an oligosaccharide component is kneaded and dispersed (see Patent Document 2) Is disclosed. However, in these methods, since the surface area of the original carrier is small, or in the case of kneading, only the surface moisturizer functions, so a sufficient amount of moisturizer is not effectively used and the moisture retention is insufficient. is there.

  Furthermore, there is an example of a composite agent with a medical or cosmetic ingredient using a polyamide resin (see Patent Document 3), but there is no mention of moisture retention, and a porous carrier having a large specific surface area is not used. The humectant is not supported and exists alone. In that case, the stickiness is bad and the touch is bad.

  Further, Patent Document 5 has composite porous fine particles composed of organic and inorganic materials. This is a structure in which a polymer is supported on the surface of porous silica and internal pores as a base material, and the shape of porous particles and Due to the non-uniform size, the feel and elongation may be different when used for cosmetics.

  In Patent Document 6 of the authors and others, polyamide porous fine particles are added to a metal compound solution dissolved in an organic solvent, and metal oxide fine particles are precipitated inside and on the surface of the polyamide porous fine particles by a sol-gel reaction. Although there are composite fine particles, there are problems such as the time and labor required for precipitation by the sol-gel method, and the particle size and segregation of the precipitated inorganic compound are difficult to control.

    Furthermore, in the patent document 7 of the authors and the like, when polyamide porous fine particles are used in a cosmetic composition, the light scattering characteristics of the porous fine particles reduce abnormal light reflection on the skin surface, and are effective in hiding fine lines. However, it does not describe the addition of functions by compounding.

JP-A-8-165219 JP 2006-328245 A JP-A-2005-47893 JP 2004-346309 A Japanese Patent Laid-Open No. 11-171947 JP 2002-26562 A WO2004 / 043411

  The present invention has a specific particle size and a narrow particle size distribution, and by carrying a moisturizing compound on the inner and outer peripheral surfaces of polyamide porous fine particles having a specific BET specific surface area and an average pore size, It is an object of the present invention to provide composite fine particles having a composite effect that has the moisture retention property possessed by the held compound and that does not impair the optical properties inherent in the porous polyamide fine particles, by an industrially easy technique.

  As a result of intensive studies to solve the above problems, the present inventor has made the present invention. That is, the present invention is as follows.

(1) The number average particle size is 1 to 30 μm, the ratio of the volume average particle size to the number average particle size (PDI) is 1.0 to 2.0, the average pore size is 0.01 to 0.5 μm, and BET A composite polyamide porous material in which a moisturizing compound is supported on the outer peripheral surface or / and inside the pores of a porous polyamide fine particle having a specific surface area of 0.1 to 80 m ² / g and a porosity (RI) of 5 to 100 Fine particles.
(2) The composite polyamide porous fine particles according to (1), wherein the porosity of the polyamide porous fine particles before supporting the moisturizing compound is 30% to 70%.
(3) The composite polyamide porous fine particles according to (1) or (2), wherein the polyamide porous fine particles before supporting the moisturizing compound have a boiled linseed oil absorption of 150 ml / 100 g or more.
(4) The composite polyamide porous fine particles according to any one of (1) to (3), wherein the moisturizing compound is at least one selected from polysaccharides, oligosaccharides, and sugar alcohols.
(5) The composite polyamide porous fine particles according to any one of (1) to (4), wherein the moisturizing compound is at least one selected from ureas, amino acids, and alcohols.
(6) The composite polyamide porous fine particles according to any one of (1) to (5), wherein the average weight fraction of the moisturizing compound is 0.01 to 60%.

(7) The moisturizing compound is dissolved in a good solvent (D) for the moisturizing compound, then the polyamide porous fine particles (C) are added and stirred, and the poor solvent (E) for the moisturizing compound is added (1) ) To (6). The method for producing a composite polyamide porous fine particle according to any one of (6) to (6).
(8) Any one of (1) to (6) above, wherein the moisturizing compound is dissolved in a good solvent (D) for the moisturizing compound, and then the polyamide porous fine particles (C) are added to remove the solvent. This is a method for producing the composite polyamide porous fine particles described in 1.
(9) In cosmetics supplied in the form of foundation powder, foundation cream, cleansing cream, cleansing oil, shaving cream, lip balm, lipstick, mascara, as described in any one of (1) to (6) above A cosmetic composition in which composite porous fine particles are dispersed.

  Compared to the case where the composite polyamide porous fine particles of the present invention and the production method thereof are prepared using spherical fine particles by supporting a moisturizing compound in the pores and on the surface of the polyamide porous fine particles, Many moisturizing compounds can be easily carried inside. As a result, it becomes a novel functional material having both the moisture retention function possessed by the moisture retention compound and the high specific surface area and light scattering function inherent in the polyamide porous fine particles.

The present invention relates to composite fine particles having a specific particle size and particle size distribution, and having a moisturizing compound supported on internal pores and outer peripheral surfaces of polyamide porous fine particles having specific BET specific surface area and average pore size. It is about.

  Various known polyamides can be used as the polyamide constituting the porous particles. For example, it can be obtained by ring-opening polymerization of a cyclic amide or polycondensation of a dicarboxylic acid and a diamine. As monomers, polycondensation of amino acids such as crystalline polyamide obtained by ring-opening polymerization of cyclic amides such as ε-caprolactam and ω-laurolactam, ε-aminocaproic acid, ω-aminododecanoic acid, ω-aminoundecanoic acid, etc. Or dicarboxylic acids and derivatives such as succinic acid, adipic acid, sebacic acid, terephthalic acid, isophthalic acid, 1,4-cyclohexyldicarboxylic acid, and ethylenediamine, hexamethylenediamine, 1,4-cyclohexyldiamine, m-xylylenediamine, penta Those obtained by polycondensation of diamines such as methylenediamine and decamethylenediamine.

  The polyamide is a polyamide composed of a homopolymer and a copolymer thereof, or a derivative thereof. Specifically, polyamide 6, polyamide 66, polyamide 11, polyamide 12, polyamide 610, polyamide 66 / 6T (T represents a terephthalic acid component. 66 / 6T is a copolymer of polyamide 66 and polyamide 6T. And so on. Moreover, the mixture of the said polyamide may be sufficient. Particularly preferred are polyamide 6 and polyamide 66.

  The molecular weight of the polyamide is 2,000-100,000. Preferably it is 5,000-40,000.

  The polyamide porous fine particles in the present invention are a simple substance or a mixture of a spherical shape, a substantially spherical shape, a slanted ball shape, or a dumbbell shape, but 70% by weight or more, preferably 80% by weight or more, more preferably, of all polyamide porous fine particles. It is desirable that 90% by weight or more is a uniform particle composed of one kind of particle shape selected from a spherical shape, a substantially spherical shape, a pendulum shape, and a dumbbell shape. If it is lower than 70% by weight, the moisturizing compound may not be uniformly supported due to variations in particle shape.

  The polyamide porous fine particles in the present invention have a number average particle diameter of 1 to 30 μm, preferably 1 to 25 μm. When the number average particle diameter is smaller than 1 μm, the secondary cohesive force is strong, and the handling operation is deteriorated. When it is larger than 30 μm, the adhesion to the skin may be lowered when handled as a cosmetic.

  The ratio (PDI) of the volume average particle diameter to the number average particle diameter of the polyamide porous fine particles in the present invention is 1 to 2, preferably 1 to 1.5. More preferably, it is 1-1.3. When the ratio of the volume average particle size to the number average particle size (particle size distribution index PDI) is larger than 2, the particle size distribution becomes wide. A uniform particle size is preferable when it is applied to a functional material or an electronic material because physical and chemical properties more than expected may be expressed.

  The average pore diameter of the polyamide porous fine particles in the present invention is 0.01 to 0.5 μm, preferably 0.01 to 0.3 μm. When the average pore diameter is smaller than 0.01 μm, the moisturizing compound cannot be sufficiently supported in the pores. On the other hand, if it is larger than 0.5 μm, the moisturizing compound fine is agglomerated and easily carried in the pores and on the surface, and the moisturizing performance by the moisturizing compound may be lowered.

The BET specific surface area of the polyamide porous fine particles in the present invention is 0.1 to 80 m ² / g, preferably 3 to 75 m ² / g, and more preferably 5 to 70 m ² / g. When the BET specific surface area is lower than 0.1 m ² / g, the moisturizing compound cannot be sufficiently supported. The larger the BET specific surface area, the more moisturizing compound can be supported. However, if the BET specific surface area is too large, the mechanical strength of the polyamide porous fine particles tends to be low, and the treatment for supporting the moisturizing compound tends to be difficult.

  The porosity (RI) of the polyamide porous fine particles in the present invention is 5 to 100, preferably 10 to 80. When the porosity is less than 5, the moisture retaining compound cannot be sufficiently supported.

  The porosity of the polyamide porous fine particles in the present invention is preferably 30% to 70%. If the porosity is lower than 30%, the moisturizing compound cannot be sufficiently carried inside. If it is more than 70%, the polyamide porous fine particles cannot be kept in a uniform shape, and the handling may be deteriorated.

The amount of boiled linseed oil absorbed by the method according to JIS K 5101 of the polyamide porous fine particles in the present invention is 150 ml / 100 g or more, preferably 150 to 350 ml / 100 g, more preferably 200 to 300 ml / 100 g. .
If the amount of oil absorption is too small, the proportion of the moisturizing compound that can be carried on the polyamide porous fine particles may decrease.

The polyamide porous fine particles in the present invention preferably have a spherulite structure. By using spherulites, the degree of crystallinity is increased and the thermal stability is improved.
Moreover, the polyamide porous fine particles in the present invention preferably have a shape in which a large number of polymer fibrils extend radially from the center. By having this shape, the pores of the polyamide porous fine particles become larger from the central portion toward the outer surface, so that the moisturizing compound supported in the pores easily exudes out of the polyamide porous fine particles, A moisturizing effect is more easily exhibited.

  The polyamide porous particles of the present invention are crystalline and preferably have a melting point of 110 to 320 ° C. More preferably, it is 130-280 degreeC. When the melting point is lower than 110 ° C., the thermal stability is lowered, and the methods that can be used are limited in the production of polyamide porous fine particles, the moisturizing compound loading treatment, and the drying treatment.

  Furthermore, the polyamide porous particles of the present invention preferably have a crystallinity measured by DSC of 40% or more. The crystallinity of polyamide can be determined by X-ray analysis, DSC measurement, or density. The DSC measurement is preferred. The degree of crystallinity of the polyamide crystallized from the ordinary melt is at most about 30%. The polyamide of the present invention preferably has a crystallinity higher than 40%. If the crystallinity is low, the thermal stability tends to be poor.

  The polyamide porous particles of the present invention have a ratio (PDI) of volume average particle diameter (or volume reference average particle diameter) to number average particle diameter (or number reference average particle diameter) in the particle size distribution of 1 to 2.5. It is preferable that More preferably, it is 1-1.5. When the PDI is larger than 2.5, handling as a powder becomes worse.

  The polyamide porous particles can be produced by dissolving the polyamide in a good solvent for the polyamide, lowering the solubility of the solution in the polyamide, and precipitating the polyamide.

  As a preferred method, a polyamide is a non-solvent at a low temperature, but after using a solvent that dissolves the polyamide at a high temperature and dispersing the polyamide in the solvent, the temperature is increased to increase the solubility of the solvent in the polyamide. After making it a polyamide solution by dissolving it, the polyamide solution can be prepared by reducing the solubility of the solvent in polyamide by lowering the temperature of the polyamide solution.

Polyamides and mixtures thereof are examples of solvents that are polyamide non-solvents at low temperatures but dissolve polyamides at high temperatures.
Examples of the polyhydric alcohol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, glycerin, propylene glycol, dipropylene glycol, 1,5-pentanediol, and hexylene glycol. Etc.

  In order to promote dissolution in the solvent, an inorganic salt may be added to lower the dissolution temperature. The inorganic salt may be any inorganic salt that promotes dissolution by acting on the hydrogen bond portion of the polyamide. There is no particular limitation, and specific examples include calcium chloride and lithium chloride.

  As a more preferable method, the solvent is obtained by mixing the polyamide solution (A) in which the polyamide is dissolved in the good solvent in which the polyamide is dissolved at around room temperature with the non-solvent (B) which is unable to dissolve the polyamide at around room temperature. Can be produced by using a method of reducing the solubility of polyamide in polyamide. The particles made by this method are porous particles in which the single particles themselves have a spherulite structure.

  “Single particles themselves have a spherulite structure” means that the polymer fibrils are three-dimensionally or radially grown from one or more cores near the center of a single particle. It means that the spherulite structure.

  As the good solvent around room temperature of the polyamide in the present invention, a phenol compound or formic acid is preferable. Specifically, phenol, 0-cresol, m-cresol, p-cresol, cresolic acid, chlorophenol and the like are preferable as the phenol compound. These are preferable because the crystalline polyamide is dissolved or accelerated by heating at room temperature or at a temperature of 30 to 90 ° C. Particularly preferred is phenol. Phenol is less toxic than other solvents and is safe for work. Further, it is convenient because it is easily distilled off from the obtained porous fine particles.

  A freezing point depressant may be added to the polyamide solution (A). As the freezing point depressant, a non-solvent of polyamide can be used as long as the polyamide in the polyamide solution is not precipitated. Examples of freezing point depressants include water, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, 2-methyl-2-propanol, 1-pentanol, Mention may be made of 1-hexanol, ethylene glycol, triethylene glycol, propylene glycol, glycerol and diglycerol.

  In order to promote dissolution in the polyamide solvent, an inorganic salt may be added to improve the solubility of the polyamide. Examples of the inorganic salt include calcium chloride and lithium chloride. The above is not limited as long as the metal salt is an inorganic salt that acts on the hydrogen bond portion of the polyamide to promote dissolution.

  The polyamide concentration in the polyamide solution (A) is preferably in the range of 0.1 to 30% by weight, more preferably in the range of 0.2 to 25% by weight. If the proportion of polyamide in the polyamide solution exceeds 30% by weight, it may be difficult to dissolve and a uniform solution may not be obtained. Moreover, even if it melt | dissolves, the viscosity of a solution becomes high and there exists a tendency which becomes difficult to handle. When the proportion of polyamide is lower than 0.1% by weight, the polymer concentration tends to be low and the product productivity tends to be low.

  The non-solvent (B) in the vicinity of room temperature of the polyamide of the present invention is preferably one that is at least partially compatible with the good solvent of the polyamide solution (A). Examples of the non-solvent (B) include compounds selected from the group consisting of water and polyamide-insoluble organic solvents. The non-solvent (B) may be a mixture of two or more solvents. The non-solvent (B) is preferably one that does not dissolve 0.01% by weight or more of the polyamide in the polyamide solution at a liquid temperature of 25 ° C.

  Examples of the polyamide-insoluble organic solvent near room temperature include alkylene glycols such as ethylene glycol and propylene glycol.

  Other examples of the polyamide-insoluble organic solvent near room temperature include monohydric and trihydric alcohols. The monohydric alcohol is preferably a monohydric alcohol having 1 to 6 carbon atoms. It may be linear or branched. Examples of monohydric alcohols include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, 2-methyl-2-propanol, 1-pentanol, 1- Mention may be made of hexanol, ethylene glycol, triethylene glycol, propylene glycol. Examples of the trihydric alcohol include glycerin. Moreover, acetone can be mentioned as a ketone.

  When the polyamide is polyamide 6, the non-solvent (B) is preferably a mixture containing water and a polyamide-insoluble solvent (preferably a monohydric alcohol). When the polyamide is polyamide 12, it is a mixture containing alkylene glycol and a polyamide-insoluble organic solvent (preferably a trihydric alcohol) other than alkylene glycol in the non-solvent (B).

  In order to prepare the porous polyamide fine particles, a method in which the solution (A) and the non-solvent (B) are mixed to temporarily form a uniform mixed solution and then allowed to stand can be used. Quality polyamide particles are deposited. The liquid temperature of the mixed solution for depositing the porous polyamide particles is preferably in the range of 0 ° C to 80 ° C, particularly preferably in the range of 20 ° C to 40 ° C.

  To the mixed solution of the polyamide solution (A) and the non-solvent (B) of polyamide, a thickener may be added to increase the viscosity of the mixed solution for the purpose of preventing aggregation of the precipitated polyamide particles. Examples of thickeners include polyalkylene glycols having a number average molecular weight of 1000 or more (particularly in the range of 1100 to 5000). Examples of polyalkylene glycols include polyethylene glycol and polypropylene glycol. As a method for adding a thickener, either a method of adding a thickener at the same time as mixing a polyamide solution and a non-solvent B, or a method of adding a thickener to a mixed solution immediately after adjustment is used. There may be. Two or more polyalkylene glycols can be used in combination.

The order of adding the polyamide solution and the non-solvent is not particularly limited as long as the uniformity of the solution is maintained.
In the present invention, the prepared polyamide porous fine particles can be solid-liquid separated by a method such as decantation, filtration or centrifugation.

  In the present invention, the prepared polyamide porous fine particles are obtained by bringing a polyamide non-solvent compatible with the good solvent of the polyamide solution (A) at a temperature of 40 ° C. or higher at a temperature of 40 ° C. or higher, The good solvent can be extracted and removed from the polyamide porous fine particles.

  Examples of the polyamide non-solvent used to extract and remove the good solvent of the polyamide solution (A) are selected from the group consisting of aliphatic alcohols, aliphatic or aromatic ketones, aliphatic or aromatic hydrocarbons, and water. List compounds. The non-solvent may be a mixture of two or more types, and preferably has a solution temperature of 40 ° C. and does not dissolve 0.01% by weight or more of polyamide.

  Examples of the aliphatic alcohol include monovalent aliphatic alcohols having 1 to 3 carbon atoms such as methanol, ethanol, 1-propanol, and 2-propanol.

  Examples of the aliphatic ketone include acetone and methyl ethyl ketone. Examples of aromatic ketones include acetophenone, propiophenone, and butyrophenone.

  Examples of aromatic hydrocarbons include toluene and xylene. Examples of aliphatic hydrocarbons include heptane, hexane, octane, and n-decane.

  In the present invention, the prepared polyamide porous fine particles can be finally made into a dry powder through a drying step. As a drying method, general-purpose powder drying methods such as vacuum drying, constant temperature drying, spray drying, freeze drying, fluidized tank drying and the like can be used.

  Examples of the moisturizing compound in the present invention include polysaccharides such as hyaluronic acid, fucoidan, chondroitin sulfate, dermatan sulfate, alginic acid, and salts thereof, or chitin, chitosan, and oligosaccharides such as trehalose, maltose, lactose, sucrose, and palatinose. Sugar alcohols such as galactooligosaccharides and fructooligosaccharides such as erythritol, xylitol and arabitol sorbitol, ureas such as urea and 2-hydroxyethylurea, amino acids such as serine, glycine, citrulline, alanine, proline, threoline and glutamic acid , Aspartic acid or the like, or trimethylglycine as an amino acid derivative, alcohols such as glycerin, 1,3-butanediol, 1,2-pentanediol, 1 2-hexanediol, ethylene glycol, propylene glycol, or mixtures thereof.

  The weight fraction of the moisturizing compound in the composite fine particles in the present invention is 1% to 60%, preferably 0.05% to 50%, more preferably 0.1% to 40%. If the weight of the moisturizing compound is less than 1%, the moisturizing function cannot be exhibited. If the weight of the moisturizing compound is larger than 60%, the moisturizing compound exists alone, and partly cannot be supported well.

There are the following two methods for producing a composite polyamide porous fine particle by supporting a moisturizing compound inside the pores and on the outer peripheral surface of the polyamide porous fine particle. That is,
1) It is obtained by dissolving a moisturizing compound in a good solvent (D), adding and dispersing polyamide porous fine particles (C) therein, and adding a poor solvent (E).
2) It is obtained by dissolving a moisturizing compound in a good solvent (D), adding and dispersing the polyamide porous fine particles (C) therein, and then gradually removing the solvent.

  In the present invention, the solvent used for preparing the solution of the moisturizing compound and combining with the polyamide porous fine particles is a good solvent for the moisturizing compound and a non-solvent for the polyamide porous fine particles. In particular, water, an organic solvent having a good affinity for water, and a mixture thereof are preferable. Specific examples of organic solvents having good affinity for water include acetone, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 1-pentanol, 1-hexanol ethylene glycol, triethylene glycol, Examples include propylene glycol, glycerin, diglycerin and mixtures thereof.

  The polyamide porous fine particles in the present invention are obtained by using an appropriate surfactant for improving the dispersibility in the solvent or for improving the binding property between the moisturizing compound and the polyamide porous fine particles. It can be coated with organic matter.

  Examples of the surfactant include an anionic surfactant, a cationic surfactant, and a nonionic surfactant.

  Examples of the anionic surfactant include fatty acid soaps such as sodium laurate and sodium palmitate, higher alkyl nitrate esters, alkyl ether sulfate esters, higher fatty acid amide sulfonates, and phosphate ester salts. It is done.

  Examples of the cationic surfactant include alkyltrimethylammonium chloride and dialkyldimethylammonium chloride.

  Examples of the nonionic surfactant include (poly) glycerin fatty acid ester, sorbitan fatty acid ester, sucrose fatty acid ester, polyoxyalkylene (carbon number 2 or 3) alkyl ether, polyoxyethylene fatty acid ester, polyoxyethylene sorbitan fatty acid ester And polyoxyethylene glycerin fatty acid ester, polyoxyethylene hydrogenated castor oil, polyoxyethylene hydrogenated castor oil fatty acid ester, polyoxyethylene / polyoxypropylene block copolymer, and the like.

  One of the methods for compounding by holding the moisturizing compound inside the pores and on the surface of the porous polyamide fine particles is to add each moisturizing compound to the container together with a solvent to create a solution, and then the polyamide porous fine particles Is added later to disperse, and it is obtained by adding a poor solvent while stirring the slurry solution.

Examples of the stirring method of the slurry solution include a method using a three-one motor and a stirring blade, a method using a stirrer and a magnetic stirrer, a method using an ultrasonic homogenizer, and a combination of these.
The poor solvent is not particularly limited as long as it does not dissolve the moisturizing compound and does not dissolve the polyamide porous fine particles, but preferably does not separate from the solvent in which the moisturizing compound is previously dissolved. For example, if a moisturizing compound is dissolved in water in advance, a hydrophilic solvent such as ethanol or acetone can be used. If the moisturizing compound is dissolved in advance in ethanol, tetrahydrofuran, toluene, or the like can be used. Hydrophobic solvents can also be used.

  The fine particles combined with a poor solvent can be solid-liquid separated by a method such as decantation, filtration or centrifugation. Moreover, it can be made to dry later using vacuum drying or constant temperature drying.

  Another method of making a composite by supporting the moisturizing compound inside and on the pores of the polyamide porous fine particles is to dissolve the moisturizing compound in a good solvent, and then add the polyamide porous fine particles to the dispersion to disperse. And gradually removing the solvent.

  Examples of the method for removing the solvent include a method of distilling off with an evaporator under reduced pressure, a method of heating at normal pressure, and the like.

  When the solvent is distilled off, it is necessary to take an appropriate amount of time since the moisturizing compound may be unevenly distributed and supported on the porous fine particles if it is dried too quickly.

  The composite polyamide porous fine particles of the present invention can be supplied as functional particles for catalyst carriers, cosmetics, optical parts in the electronic field, coatings, medical use, and food industry.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these Examples. The crystallinity, particle diameter, average pore diameter, porosity, specific surface area, oil absorption, PDI, visible-ultraviolet absorption spectrum, optical reflection characteristics and the like were measured as follows.

(Crystallinity)
The crystallinity of the polyamide fine particles was measured by DSC (differential scanning calorimeter). In a nitrogen stream with a flow rate of 40 ml / min, the heat of crystal fusion is calculated from the area of the endothermic peak at a temperature rising rate of 5 ° C./min and a temperature range of 120 to 230 ° C. The degree of crystallinity is obtained from the ratio between the calculated heat of fusion and the heat of crystal fusion of polyamide 6 or polyamide 12. The heat of crystal fusion of polyamide 6 was 189 J / g, and the heat of crystal fusion of polyamide 12 was 209 J / g.

(Average particle size)
The average particle size and particle size distribution of the polyamide porous fine particles were measured as an average value of 100 fine particles using an electron microscope (scanning electron microscope (SEM)). The number average particle size, volume average particle size, and particle size distribution index (PDI) are expressed by the following equations.
Number average particle size:
Volume average particle size:

Particle size distribution index:
Here, Xi: individual particle diameter, n is the number of measurements.

(Specific surface area)
The specific surface area of the polyamide porous fine particles was measured at three points by the BET method using nitrogen adsorption.

(Average pore diameter / porosity)
The average pore diameter of the polyamide porous fine particles was measured with a mercury porosimeter. The average pore diameter was determined in the measurement range of 0.0036 to 14 μm. The porosity of the polyamide porous fine particles represents the ratio of the volume of polyamide to the volume of space in one particle. Here, the density of polyamide can be represented by ρ, and the porosity can be expressed by the following equation. Where Vp: pore volume in the particle,
Vs: Intraparticle polymer volume.
[Equation 4]
P = Vp / (Vp + Vs)
That is, when the cumulative pore volume in the particle (P1) is given, [Equation 5]
P = P ₁ / (P ₁ + (1 / ρ)) × 100
It can be expressed as
From the figure of the cumulative pore volume with respect to the pore diameter, the intra-particle cumulative pore volume is calculated, and the intra-particle porosity is calculated according to [Equation 4]. At this time, the density ρ of the polyamide fine particles is calculated from the crystallinity χ, crystal density ρc, and amorphous density ρa obtained by DSC [Equation 6]
ρ = χ · ρc + (1−χ) · ρa
It was obtained from. Wherein the crystal density of polyamide 6 is 1.23cm ³ / g, crystal density of the amorphous density 1.09cm ³ / g, polyamide 12 and 1.1 cm ³ / g, the amorphous density of 0.99cm ³ / g did.

The degree of porosity (RI) of the polyamide porous fine particles can be expressed by the ratio of the specific surface area value Sp0 when assuming spherical particles with the same particle diameter and the BET specific surface area Sp in the case of porous fine particles. That is,
[Equation 7]
RI = Sp / Sp ₀
[Equation 8]
Sp ₀ = 6 / d / ρ

It is obtained by. d is the diameter of the particle and ρ is the density.

  The amount of oil absorption of the porous polyamide fine particles was measured according to JIS K 5101.

  The presence of the moisturizing compound in the composite polyamide porous microparticles was confirmed by SEM photographs of the composite microparticle surfaces.

  Visible-ultraviolet absorption spectra of the polyamide porous fine particles alone and the composite polyamide porous fine particles were measured by using a visible-ultraviolet spectroscope to fill each quartz glass cell with each fine particle and measuring the reflectance from 300 nm to 800 nm.

  The optical reflection characteristics of the polyamide porous fine particles and the composite porous fine particles were obtained from Han Color System Co., Ltd., and a variable angle spectroscopic color system color robot 3 was used. For the measurement sample, only the PET release liner one side of a transparent double-sided tape CS9621 (10 cm × 10 cm) made by Nitto Denko Corporation is peeled off, and a powder foundation sponge (Cosmedecorte AQ makeup sponge M) made by Kose is used. After uniformly applying 0.2 g of the powder in the surface, the powder not adhered to the adhesive surface was removed using a dust removing air spray (Engineer Aeroduster). The incident light was fixed at 45 °, the light receiving angle was measured in increments of 5 ° from 0 to 80 °, and the values of 0 °, 20 °, and 45 ° were compared as representative values.

[Example 1]
(1) 50 g of polyamide 6 (manufactured by Ube Industries, Ltd., 1013B, molecular weight 13,000) was dissolved in 950 g of an m-cresol solution to obtain an m-cresol solution having a concentration of 5% by weight. While stirring this solution, 6 kg of a mixture consisting of 4 kg of isopropyl alcohol and 2 kg of water was added over 40 seconds. Stirring was continued, and when the solution became homogeneous, stirring was stopped and allowed to stand. After a while, polyamide 6 particles precipitated. After further standing for 2 hours, the precipitate was filtered off using a filter paper, and then washed with 10000 ml of methanol at 25 ° C. about 3 times on the filter paper. Next, it was dried with a hot air dryer at a temperature of 60 ° C. for 8 hours. Furthermore, it dried for 8 hours at the temperature of 60 degreeC with the vacuum dryer. 10 g of dried polyamide 6 porous fine particles were charged into a heat-insulated Soxhlet extractor, and isopropyl alcohol was refluxed in the extractor for 10 hours to contact the polyamide 6 porous fine particles. Next, the dry fine particles were made into a 10% by weight water slurry and spray-dried at 180 ° C.
When the obtained particles were observed with a scanning electron microscope, they were relatively uniform spherical particles having a number average particle diameter of 13.7 μm and a volume average particle diameter of 14.4 μm. The PDI was 1.05. The BET specific surface area was 15.6 m ² / g, the average pore diameter was 0.096 μm, and the RI was 41.6. The heat of fusion Hf was 107.8 J / g, the crystallinity was 57%, and the porosity was 61%. The oil absorption of boiled linseed oil was 210 ml / 100 g.

(2) As a moisturizer, 1 g of fucoidan (“Ubefu Koidan” (registered trademark), manufactured by Ube Industries)), which is a kind of polysaccharide, is weighed in a container, dissolved in 200 g of water, and then dried polyamide (1). 6 g of porous fine particles were added and dispersed with a magnetic stirrer to prepare a slurry. Thereto was gradually added 400 g of ethanol to form a composite material. After filtration, vacuum drying was performed at 60 ° C. for 8 hours to obtain composite polyamide porous fine particles. Observation of dry fine particles using SEM confirmed that fucoidan was supported on the surface of the porous fine particles, and that the porous pores were blocked in some places by fucoidan.
The average weight fraction of the moisturizing compound was 16.7%.

[Example 2]
Composite polyamide porous fine particles were obtained in the same manner as in Example 1 except that sodium hyaluronate (“Bio Sodium Hyaluronate HA12” manufactured by Shiseido Co., Ltd.) was used as a humectant. Observation of the dried fine particles using SEM confirmed that sodium hyaluronate was supported on the surface of the porous fine particles, and that the porous pores were blocked with sodium hyaluronate in some places.
The average weight fraction of the moisturizing compound was 16.7%.

[Example 3]
1 g of betaine (manufactured by Tokyo Chemical Industry Co., Ltd.) was dissolved in ethanol, and then 5 g of the dry polyamide 6 porous fine particles of Example 1 (1) were added and dispersed with a magnetic stirrer to prepare a slurry. The solvent was gradually distilled off at a bath temperature of 50 ° C. and a reduced pressure of 100 mmHg, and finally the solvent was completely removed at 5 mmHg to obtain composite polyamide porous fine particles. When the dried fine particles were observed using SEM, it was confirmed that betaine was supported on the surface of the porous fine particles as shown in FIG. 1, and porous pores were blocked with betaine in some places. Moreover, no stickiness was felt.
The average weight fraction of the moisturizing compound was 16.7%.

[Comparative Example 1]
When the general-purpose polyamide 12 true spherical fine particles were observed with an SEM photograph, the surface was true spherical and pores associated with the porous material could not be confirmed. When the particle size of the particles was examined, the number average particle size was 5.4 μm, the volume average particle size was 9.3 μm, and the PDI was 1.72. Specific surface area was 1.49 m ² / g, heat of fusion Hf was 42.8 J / g, crystallinity was 20.4%, RI was 1.35, and boiled linseed oil absorption was 80 ml / 100 g. . A composite polyamide porous fine particle was obtained in the same manner as in Example 2 except that 1 g of this polyamide 12 true spherical fine particle was changed to a polyamide porous fine particle. When dried fine particles were observed using SEM, it was confirmed that betaine was partially supported on the surface of the true spherical fine particles. However, at the same time, a large number of betaine particles existed alone in SEM observation, and it was found that many of the added betaines were not carried effectively.

[Example 4]
Composite fine particles were prepared in the same manner as in Example 2 except that the added humectant was 2 g of urea. As a result of observing the dry fine particles using SEM, it was confirmed that urea was supported on the surface of the porous fine particles, and the porous pores were blocked in some places with urea.
The average weight fraction of the moisturizing compound was 28.6%.

[Example 5]
(1) After completely dissolving 100 g of polyamide 6 (manufactured by Ube Industries, “1010X1”, number average molecular weight 8000) in phenol 810 g at 70 ° C., 90 g of isopropyl alcohol was added, and the mixture was slowly cooled with stirring to obtain a nylon concentration. A 10% by weight phenol / isopropyl alcohol solution was obtained. At 20 ° C., 6.5 kg of a mixed solution consisting of 4 kg of isopropyl alcohol and 2.5 kg of water was mixed. When the solution became homogeneous, stirring was stopped and the mixture was allowed to stand. After a while, polyamide 6 particles precipitated. After further standing for 2 hours, the precipitate was filtered off using filter paper, and then washed about 5 times with 10000 ml of isopropyl alcohol at 25 ° C. on the filter paper. Next, it was dried with a hot air dryer at a temperature of 60 ° C. for 8 hours. Furthermore, it dried for 8 hours at the temperature of 60 degreeC with the vacuum dryer. 10 g of dried polyamide 6 porous fine particles were charged into a heat-insulated Soxhlet extractor, and isopropyl alcohol was refluxed for 10 hours in the extractor and brought into contact with the polyamide 6 porous fine particles. Next, the dry fine particles were made into a 10% by weight water slurry and spray-dried at 180 ° C. When the obtained particles were observed with a scanning electron microscope, they were relatively uniform spherical particles having a number average particle diameter of 8.2 μm and a volume average particle diameter of 11.8 μm. The PDI was 1.43. The BET specific surface area was 28.2 m ² / g, the average pore diameter was 0.095 μm, RI was 45.0, and the oil absorption of boiled linseed oil was 210 ml / 100 g. The heat of fusion Hf was 106.0 J / g, the crystallinity was 57%, and the porosity was 65%.

(2) 1 g of 2-hydroxyethylurea was dissolved in ethanol, and then 5 g of porous fine particles of dry polyamide 6 of Example 5 (1) were added and dispersed with a magnetic stirrer to prepare a slurry. The solvent was gradually distilled off at a bath temperature of 50 ° C. and a reduced pressure of 100 mmHg, and finally the solvent was completely removed at 5 mmHg to obtain composite polyamide porous fine particles. Observation of dried fine particles using SEM confirmed that 2-hydroxyethylurea was supported on the surface of the porous fine particles, and porous pores were blocked with 2-hydroxyethylurea in some places.
The average weight fraction of the moisturizing compound was 16.7%.

[Example 6]
Polyamide composite fine particles were prepared in the same manner as in Example 5 except that the humectant was trehalose. Observation of dried fine particles using SEM confirmed that trehalose was supported on the surface of the porous fine particles, and that most porous pores were blocked with trehalose.
The average weight fraction of the moisturizing compound was 16.7%.

[Example 7]
(4) The composites obtained in Examples 3, 4, and 5 (2) were dried in a hot air dryer set at 50 ° C. until there was no weight loss (W0). Subsequently, the sample was left in a constant temperature and humidity chamber set at 25 ° C. and 90% RH for 12 hours (measurement of moisture absorption, W1), and the change in weight over time at 25 ° C. and 50% RH was measured (becomes constant weight). Time points are moisture retention, W2).

In Table 1, Example 1 (1) refers to polyamide porous fine particles not supporting a moisturizing compound.

[Equation 9]
Moisture absorption Wa = W1 / (W1-W0) × 100
[Equation 10]
Water retention amount Wr = W2 / (W2-W0) × 100
Thus, the powders of Examples 3 to 5 were confirmed to be moisturizing and non-sticky.

[Example 8]
(Powder foundation)
Composite polyamide porous fine particles of Example 3, 5.0%, talc 35.0%, mica 30.0%, synthetic phlogopite 10.0%, titanium oxide 5.0%, aluminum hydroxide 3.0%, Formulation of stearic acid 4.0%, iron oxide 3.0%, butylparaben 0.2%, methylparaben 0.1%, dimethicone 9.0%, methicone 1.7%, trimethylsiloxysilicic acid 4.0% or more A blended product was prepared. In this blended product, the moist feeling persisted as compared with the powder prepared in Example 1 (1) with the same blending ratio.

  The composite polyamide porous fine particles or / and the production method of the present invention are compared with the case where the polyamide porous fine particles are prepared using true spherical fine particles by carrying a moisturizing compound inside and on the surface of the polyamide porous fine particles. Many moisturizing compounds can be easily carried inside. This makes it a new functional material that combines the moisture retention function of a moisture retention compound with the inherently high specific surface area and light scattering function of polyamide porous microparticles. In many industrial fields such as cosmetic materials, electronic materials, and medical materials. Available.

FIG. 1 is a surface SEM photograph of composite polyamide porous fine particles obtained in Example 3 of the present invention. It is a cross-sectional photograph of the porous fine particles of polyamide 6 obtained in Example 1 (1) and not carrying a humectant.

Claims (10)

The number average particle diameter is 1 to 30 μm, the ratio of the volume average particle diameter to the number average particle diameter (PDI) is 1.0 to 2.0, the average pore diameter is 0.01 to 0.5 μm, and the BET specific surface area is Composite polyamide porous fine particles in which a moisturizing compound is supported on the outer peripheral surface or / and inside the pores of a porous polyamide fine particle having a porosity of 0.1 to 80 m ² / g and a porosity (RI) of 5 to 100.   The composite polyamide porous fine particles according to claim 1, wherein the porosity of the polyamide porous fine particles before supporting the moisturizing compound is 30% to 70%.   3. The composite polyamide porous fine particle according to claim 1, wherein the polyamide porous fine particle before supporting the moisturizing compound has an oil absorption of boiled linseed oil measured by a method according to JIS K 5101 of 150 ml / 100 g or more.   The composite polyamide porous fine particles according to any one of claims 1 to 3, wherein the polyamide porous fine particles before supporting the moisturizing compound have a shape in which a large number of fibrils extend radially from the center.   The composite polyamide porous microparticle according to any one of claims 1 to 3, wherein the moisturizing compound is at least one selected from polysaccharides, oligosaccharides, and sugar alcohols.   The composite polyamide porous fine particles according to any one of claims 1 to 4, wherein the moisturizing compound is at least one selected from ureas, amino acids, and alcohols.   The composite polyamide porous fine particles according to any one of claims 1 to 5, wherein an average weight fraction of the moisturizing compound is 0.01 to 60%.   The moisturizing compound is dissolved in a good solvent (D) for the moisturizing compound, then the polyamide porous fine particles (C) are added and stirred, and the poor solvent (E) for the moisturizing compound is added. The manufacturing method of the composite polyamide porous microparticle as described in any one of Claims.   The composite according to any one of claims 1 to 6, wherein the moisturizing compound is dissolved in a good solvent (D) for the moisturizing compound, and then the polyamide porous fine particles (C) are added to remove the solvent. A method for producing polyamide porous fine particles.   In the cosmetic powder supplied in the form of foundation powder, foundation cream, cleansing cream, cleansing oil, shaving cream, lip balm, lipstick, mascara, the composite porous fine particles according to any one of claims 1 to 6 Dispersed cosmetic composition.