TWI619747B - Nearly-spherical resin particle constituting by thermal plastic resin, producing method for the same and use thereof - Google Patents

Abstract

The present invention provides a substantially spherical resin particle composed of a thermoplastic resin, which has a true sphericity of 0.90 to 1.00, a light scattering index of 0.5 to 1.0, and a linseed oil absorption of 30 to 150 ml/100 g. .

Description

A substantially spherical resin particle composed of a thermoplastic resin, a method for producing the same, and a use thereof

The present invention relates to a substantially spherical resin particle composed of a thermoplastic resin which is excellent in sphericity and optical characteristics and excellent in handling characteristics during preparation, a method for producing the same, and a use thereof.

The thermoplastic resin particles are used in the modification and improvement of various materials by utilizing a large specific surface area and a structure of particles. The main use is a formulation for cosmetics such as foundations, antiperspirants, and cleaning agents, a matting agent for paints, a rheology modifier, an anti-caking agent, a slip imparting agent, a light diffusing agent, and a medical diagnostic test agent. Uses of additives such as additives, automotive materials, and building materials in molded articles.

On the other hand, in recent years, attention has been paid to environmental issues, and in order to reduce the load on the environment, it is required to use materials derived from non-petroleum materials in all fields in which resins are used. This is also required, for example, in the field of using resin particles such as cosmetics and paints.

As a method for producing a thermoplastic resin particle, a pulverization method represented by freeze pulverization is known (JP-A-2001-288273: Patent Document 1); it is dissolved in a solvent at a high temperature, and is cooled and precipitated. Or a method of dissolving and dissolving a solvent which is dissolved in a solvent and then added with a poor solvent (JP-A-2000-7789: Patent Document 2, JP-A-2005-2302: Patent Document 3, JP-A-2009) Japanese Patent Publication No. Hei 11-35693 (Patent Document 5); mixing a thermoplastic resin and an incompatible resin in a mixer of a biaxial extruder to form a thermoplastic resin in a dispersed phase; After the resin composition of the thermoplastic resin and the incompatible resin is contained in the continuous phase, the melt-kneading method of the thermoplastic resin particles can be obtained by removing the incompatible resin (JP-A-2004-269865: Patent Document 6) Japanese Laid-Open Patent Publication No. 2005-200663: Patent Document 7) and the like.

In particular, as a proposal for obtaining particles composed of a biodegradable resin, Patent Document 1 proposes a plastic or agglomerate composed of a polylactic acid-based resin at -50 ° C without using an organic solvent. A technique of cooling at a low temperature of -180 ° C while performing mechanical pulverization/classification to obtain fine particles. Further, in Patent Documents 2 to 4, it is proposed that after the polylactic acid-based resin is dissolved in an organic solvent, the solution is dropped into a poor solvent such as water, or neutralized/chlorinated to precipitate into fine particles.

Patent Document 8 (International Publication No. WO2012-105140) proposes a method of dissolving polylactic acid and different kinds of resins in an ether solvent, and then adding a shearing force to form an emulsion, and then contacting with a poor solvent to obtain a small particle. A method of porous polylactic acid-based resin particles having a large diameter and a large oil absorption.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2001-288273

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2000-7789

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2005-2302

[Patent Document 4] Japanese Patent Laid-Open Publication No. 2009-242728

[Patent Document 5] Japanese Patent Laid-Open No. Hei 11-35693

[Patent Document 6] Japanese Patent Laid-Open Publication No. 2004-269865

[Patent Document 7] Japanese Patent Laid-Open Publication No. 2005-200663

[Patent Document 8] International Publication WO2012-105140

However, the conventional thermoplastic resin particles produced by the methods of Patent Documents 1 to 7 have the following problems: the obtained particles are not spherical, the particle diameter is not fine, the particle size distribution is wide, and sometimes the fibrous material is contained. Wait. Among them, in the field of cosmetics that emphasize touch and texture, and the field of paints where control flow becomes important, conventional thermoplastic resin particles cannot sufficiently exert the effect of adding fine particles in the present case.

In particular, thermoplastic biodegradable resins are too soft or too viscous. Therefore, when powder is to be produced by general mechanical pulverization, the following problems sometimes occur:

(1) It is difficult to make fine powder

(2) The resulting powder may be mixed with a large particle size to a small particle size due to over-crushing. presence.

(3) Since the powder is further finely pulverized during use, the grinding effect cannot be sustained.

Further, in Patent Document 1, although the powder can be produced by using this technique, it is still difficult to produce a fine powder. Further, in order to handle a refrigerant such as liquid nitrogen, complicated equipment is required, or the time required for production is greatly prolonged in order to add steps, resulting in remarkably deteriorated productivity.

Further, in Patent Documents 2 to 4, since a plurality of steps of dissolution, precipitation, and drying are required, not only productivity is poor, but also a large amount of waste solvent containing impurities is generated. If the waste solvent is discharged, there is a high possibility of adversely affecting the environment, and a large labor force is required for the treatment of removing impurities for reuse. Further, at the time of this treatment, there is a high possibility that a substance that is harmful to the environment is generated. Further, a trace amount of a solvent is always left in the obtained powder, and it is feared that the residual solvent may adversely affect the quality of the final product.

In particular, in Patent Document 4, the polylactic acid-based resin is dissolved in benzene, and then the meta-xylene is mixed at less than 60 ° C to precipitate a powder of the polylactic acid-based resin. Therefore, not only a large amount of organic solvent but also a large amount of organic solvent is required. The organic solvent remains in the resin. Further, even when spherical particles are obtained, for example, in the field of cosmetics or paints, there is a particular concern that the optical characteristics cannot be sufficiently exhibited.

In Patent Document 8, although fine particles having a smooth surface are obtained, it is not possible to obtain a sufficiently excellent true sphericity and light scattering index.

The inventors of the present invention have found that the above problems can be solved by setting the true sphericity, the light scattering property of the resin particles, and the linseed oil absorption amount within a specific range, and the present invention has been completed. In addition, the resin particle is a safety of a specific structure in which the solubility of the resin at room temperature is low, but the solubility of the resin at a high temperature is high, in the solvent for emulsifying/dispersing the thermoplastic resin particles. The present invention has been completed by preparing a high alcohol solvent.

In this way, according to the present invention, a substantially spherical resin particle composed of a thermoplastic resin having a true sphericity of 0.90 to 1.00, a light scattering index of 0.5 to 1.0, and a linseed oil absorption amount can be provided. 30 to 150ml / 100g.

Further, according to the present invention, there is provided a method for producing substantially spherical resin particles composed of a thermoplastic resin, wherein the substantially spherical resin particles composed of a thermoplastic resin are contained in 3-alkoxy-3. Solvent, water and dispersion stabilizer for methyl-1-butanol and/or 3-alkoxy-3-methyl-1-butyl acetate (1 to 5 carbon atoms of alkoxy groups) In the presence of the thermoplastic resin, the thermoplastic resin is emulsified and dispersed at a temperature of 100 ° C or higher, and then cooled.

Furthermore, there is provided a cosmetic material in which substantially spherical resin particles composed of the above thermoplastic resin are blended.

Furthermore, there is provided a coating material in which substantially spherical resin particles composed of the above thermoplastic resin are blended.

According to the present invention, it is possible to provide a substantially spherical thermoplastic resin particle having high light scattering properties. Moreover, according to the present invention, a method for producing the resin particles can be easily produced.

In either case, substantially spherical thermoplastic resin particles having higher light scattering properties can be provided.

(1) The thermoplastic resin is at least one selected from the group consisting of a polyolefin resin, a polyester resin, a polyether resin, and a polyamide resin.

(2) The thermoplastic resin is selected from the group consisting of polyethylene, polypropylene, ethylene/vinyl acetate copolymer, ethylene/(meth)acrylic acid copolymer, ethylene/(meth)acrylate copolymer, polylactic acid, polysuccinic acid At least one resin selected from the group consisting of butylene ester, polyhydroxyalkanoate, nylon 12, nylon 6 and polycaprolactam.

(3) The thermoplastic resin is biodegradable and is at least one selected from the group consisting of a polyester resin and a polyether resin.

(4) The thermoplastic resin is based on 3-alkoxy-3-methyl-1-butanol and/or 3-alkoxy-3-methyl-1-butyl acetate (carbon number of alkoxy group) A resin which is dissolved or plasticizable at 100 ° C or higher in 1 to 5) and which is insoluble at normal temperature.

1‧‧‧Test piece

2‧‧‧Resin particles

3‧‧‧Double-sided tape

4‧‧‧Black ABS resin board

5‧‧‧Light

6‧‧‧Reflected light

Fig. 1 is a schematic view showing a measurement method of a light scattering index.

(Substantially spherical resin particles composed of a thermoplastic resin: hereinafter also referred to as substantially spherical particles)

(1) Various physical properties

The substantially spherical particles have a true sphericity of 0.90 to 1.00, 0.5 A light scattering index of 1.0 and a linseed oil absorption of 30 to 150 mL/100 g. The method for measuring the true sphericity, the light scattering index, and the linseed oil absorption is described in the column of the examples.

When the true sphericity is less than 0.90, when it is blended in a cosmetic or the like, the fluidity may be lowered, and the touch and lubricity may be deteriorated. The true sphericity can be 0.90, 0.92, 0.93, 0.95, 0.97 and 1.00. Preferably, the true sphericity is from 0.92 to 1.00, and more preferably the true sphericity is from 0.93 to 1.00.

When the light scattering index is less than 0.5, sufficient light-scattering property cannot be exhibited, and when the cosmetic material or the like is blended, soft focus characteristics may be deteriorated. The light scattering index can be taken as 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95 and 1.0. Preferably, the light scattering index is from 0.55 to 1.0, and more preferably the light scattering index is from 0.6 to 1.0.

Further, when the oil absorption amount of the linseed oil is in the above range, when a product comprising substantially spherical particles is produced, it is possible to impart good handling characteristics when blending substantially spherical particles. When it is less than 30 mL/100 g, when it is blended in a cosmetic or the like, it is likely to cause makeup loss, and the makeup may be deteriorated. When the oil absorption amount of the linseed oil is more than 150 mL/100 g, the other components are completely absorbed and the fluidity is lowered, so that the workability may be deteriorated. The oil absorption of linseed oil can be 30mL/100g, 50mL/100g, 80mL/100g, 100mL/100g, 120mL/100g, 145mL/100g and 150mL/100g. The better linseed oil absorption is 30 to 145 mL / 100 g.

Further, the substantially spherical particles are preferably a volume average particle diameter of from 1 to 500 μm. The volume average particle diameter can be 1 μm, 3 μm, 10 μm, 20 μm, 50 μm, 100 μm, 200 μm, 300 μm, 400 μm or 500 μm. The substantially spherical particles can be used in various particle sizes depending on the application. For example, it is 3 to 20 μm for use as a foundation, 200 to 500 μm for use as a cleaning agent, and 3 to 100 μm for use as a coating material, and can be appropriately selected depending on the application. The measurement method of the average particle diameter is described in the column of the examples.

(2) Thermoplastic resin

The thermoplastic resin is not particularly limited, and examples thereof include at least one selected from the group consisting of polyolefin resins, polyester resins, polyether resins, and polyamine resins. Examples of the polyolefin resin include polyethylene, polypropylene, ethylene/vinyl acetate copolymer, ethylene/(meth)acrylic copolymer, and ethylene/(meth)acrylate copolymer. Examples of the (meth) acrylate ester component include a methyl group, an ethyl group, a propyl group, and a butyl group. Examples of the polyester resin include polylactic acid, polybutylene succinate, polyhydroxyalkanoate, and polycaprolactam. The preferred one of polyhydroxyalkanoates is represented by the formula (1) [-CH(R)-CH ₂ CO-O-] (except that the formula R is -C _n H _2n-1 ) A poly(3-hydroxyalkanoate) polymer or copolymer composed of repeating units represented by an alkyl group, n being an integer of from 1 to 15. More specifically, 3-hydroxybutyrate can be used, and 3-hydroxypropionate, 3-hydroxyvalerate, 3-hydroxyhexanoate, 3-hydroxyheptanoate, 3-hydroxyoctanoate , 3-hydroxydecanoate, 3-hydroxydecanoate, 3-hydroxytetradecanoate, 3-hydroxyhexadecanoate, 3-hydroxyoctadecanoate, 4-hydroxybutyrate, 4 a copolymer of at least one monomer selected from the group consisting of hydroxyvalerate, 5-hydroxyvalerate and 6-hydroxycaproate. Specific examples of the (3-hydroxyalkanoate) polymer or copolymer include a homopolymer of the above 3-hydroxyalkanoate or a 2-hydroxyalkanoate having two or more different n groups. The copolymer is blended with two or more blends selected from the group consisting of the above homopolymer and the above copolymer. Wherein, the repeating unit consisting of 3-hydroxybutyrate of n=1, the repeating unit of 3-hydroxyvalerate of n=2, the repeating unit of 3-hydroxyhexanoate of n=3, the 3-hydroxyl group of n=5 a homopolymer, a copolymer, and a mixture of a group consisting of an octanoate repeating unit and a n=15 3-hydroxyoctadecanoate repeating unit, preferably a repeating unit derived from 3-hydroxybutyrate. More preferably, it is a copolymer composed of at least one repeating unit selected from the group consisting of 3-hydroxyvalerate, 3-hydroxyhexanoate and 3-hydroxyoctanoate. The most preferred is a poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) copolymer of 3-hydroxybutyrate repeating unit with 3-hydroxyhexanoate. More specifically, for example, the AONILEX series manufactured by Kaneka Co., Ltd. can be cited. Examples of the polyether-based resin include polyether oxime and the like. Examples of the polyamine-based resin include nylon 12 and nylon 6.

These exemplified resins may be used singly or in combination of plural kinds. Further, the molecular weight of the thermoplastic resin is not particularly limited. It can be appropriately selected depending on the end use/purpose.

The production method of the present invention can also be applied to at least one resin selected from the group consisting of a polyester resin and a polyether resin, which has biodegradability which is generally difficult to be particle-formed. Examples of such a resin include polyester resins such as polylactic acid, polybutylene succinate, polyhydroxyalkanoate, and polycaprolactone.

The thermoplastic resin is preferably dissolved or plasticized at a high temperature in the specific solvent described in the following production method, but is preferably a resin which is insoluble at normal temperature (about 25 ° C). Resin with such properties It is easy to provide the effect of a substantially spherical particle with a specific true sphericity and light scattering index.

(3) Other ingredients

The substantially spherical particles may contain a conventional fluidity adjusting agent, an ultraviolet absorber, a light stabilizer, a pigment (for example, an extender pigment, a coloring pigment, a metallic pigment, a mica powder pigment, etc.), a dye, etc., as needed. .

(4) Use

The substantially spherical particles can be used as a cosmetic preparation for a foundation, an antiperspirant, a cleaning agent, a matting agent for a coating, a rheology modifier, an anti-caking agent, a slip imparting agent, a light diffusing agent, It is used for various agents such as fine ceramic sintering molding aids, fillers for adhesives, medical diagnostic test agents, and additives for automobile materials and molded articles such as building materials.

(Method for producing substantially spherical resin particles composed of a thermoplastic resin)

The substantially spherical particles can be obtained by the following steps. (1) The thermoplastic resin contains 3-alkoxy-3-methyl-1-butanol and/or 3-alkoxy-3-methyl-1-butyl acetate (carbon number of alkoxy group) The thermoplastic resin is at a temperature of 100 ° C or higher in the presence of 1 to 5, specifically a solvent of a methyl group, an ethyl group, a propyl group, a butyl group and a pentyl group (specific solvent), water and a dispersion stabilizer. The step of performing emulsification/dispersion (emulsification/dispersion step); (2) a step obtained by cooling the thermoplastic resin into particles (cooling step).

According to the above production method, the skin-irritating organic solvent commonly used in the microparticulation method of a general thermoplastic resin is not used. (for example, xylene, toluene, n-methylpyrrolidone, chloroform, dichloromethane, dioxolane, THF, etc.), and using a highly safe alcohol solvent, it can be made into a spherical shape, and has a small particle size. An optically excellent thermoplastic resin particle having a narrow particle size distribution. Further, 3-alkoxy-3-methyl-1-butanol and/or 3-alkoxy-3-methyl-1-butyl acetate are biodegradable and have low skin irritation. Therefore, it is possible to suppress the adverse effects caused by the residue when used in the use of cosmetics. Furthermore, the production method of the present invention can be a biodegradable thermoplastic resin having a crystalline property such as polylactic acid (PLA), polybutylene succinate (PBS), or polyhydroxyalkanoate (PHA). A method of spheroidizing in a wet manner. Further, 3-alkoxy-3-methyl-1-butanol and/or 3-alkoxy-3-methyl-1-butyl acetate dissolves or plasticizes the thermoplastic resin at a high temperature. However, since the thermoplastic resin is not dissolved at normal temperature, the alcohol-based solvent can be easily reused, which is advantageous for industrial use.

The substantially spherical particles obtained by the production method have an effect of being excellent in optical characteristics (soft focus effect) and oil absorption characteristics as compared with particles obtained by other production methods.

(a) Emulsification/dispersion step

(i) solvent

The solvent contains 3-alkoxy-3-methyl-1-butanol and/or 3-alkoxy-3-methyl-1-butyl acetate (hereinafter also referred to as a specific solvent). The proportion of the specific solvent in the solvent is preferably 50% by weight or more, more preferably 70% by weight or more, and still more preferably 100% by weight or more. Examples of the solvent which can be used other than the specific solvent include a lower alcohol such as methanol or ethanol; and an acetate solvent such as ethyl acetate or butyl acetate. As a specific solvent, it can also be used A solvent manufactured by Kuraray under the trade name Sol fit. Further, 3-alkoxy-3-methyl-1-butanol can be produced by a method described in, for example, International Publication WO 2013/146370.

Here, the alkoxy group in the specific solvent has 1 to 5 carbon atoms. When the carbon number of the alkoxy group is more than 5, the solubility may be deteriorated. Specific examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, and a pentyloxy group. The propoxy group, the butoxy group and the pentyloxy group are not only linear but also contain structural isomers which can be taken. Preferred alkoxy groups are methoxy, ethoxy and propoxy.

The solvent is preferably used in an amount of from 100 to 1200 parts by weight based on 100 parts by weight of the thermoplastic resin. When the amount used is less than 100 parts by weight, the concentration of the thermoplastic resin is too high and it may be difficult to sufficiently stir and mix. When it is more than 1200 parts by weight, the yield sometimes decreases as compared with the size of the device. The amount used may be 100 parts by weight, 200 parts by weight, 400 parts by weight, 500 parts by weight, 700 parts by weight, 800 parts by weight, 1000 parts by weight, and 1200 parts by weight. It is preferably used in an amount of from 100 to 800 parts by weight, more preferably from 100 to 400 parts by weight.

(ii) dispersion stabilizer

The dispersion stabilizer can be used by using hydrophobized inorganic fine particles. Specific examples include hydrophobic gas phase cerium oxide (manufactured by Japan Aerosil Co., Ltd.; trade name AEROSIL _{(R: registered trademark)} R972, AEROSIL _(R) R974, AEROSIL _(R) R976S, AEROSIL _(R) R104, AEROSIL _{(R) R106, AEROSIL (R} ) R202, AEROSIL (R) R805, AEROSIL (R) R812, AEROSIL (R) R812S, AEROSIL (R) R816, AEROSIL (R) R7200, AEROSIL (R) R8200, AEROSIL (R _{) R9200, AEROSIL (R) R711} , AEROSIL (R) RY50, AEROSIL (R) NY50, AEROSIL (R) RY200, AEROSIL (R) RY200S, AEROSIL (R) RX50, AEROSIL (R) NAX50, AEROSIL (R) RX200 , AEROSIL _(R) RX300, AEROSIL _(R) R504), hydrophobic alumina (manufactured by Japan Aerosil Co., Ltd.; trade name AEROXIDO _(R) Alu C), hydrophobic titanium oxide (manufactured by Japan Aerosil Co., Ltd.; trade name AEROXIDE _(R) TiO ₂ T805: manufactured by Titanium Industry Co., Ltd.; trade name ultrafine titanium oxide ST series, ST-455, STV-455, ST-557SA, ST-457EC, ST-457EC, ST-605EC: 堺Chemical Industries, Ltd.; Ultrafine titanium oxide STR series, STR-100C-LP, STR-60c-LP, STR-100W-LP, and STR-100C-LF).

Further, as the dispersion stabilizer, a phosphate such as tricalcium phosphate (manufactured by Taiping Chemical Industry Co., Ltd.; trade name: TCP-10U), a phosphate such as magnesium phosphate, aluminum phosphate or zinc phosphate; calcium pyrophosphate, magnesium pyrophosphate, and pyrophosphate may be used. Pyrophosphate such as aluminum and zinc pyrophosphate; calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, colloidal cerium oxide (manufactured by Nissan Chemical Co., Ltd.: commodity Hydrophilic insoluble inorganic compounds such as Snow Tex 40, Snow Tex S, Snow Tex X, etc.

Among the above, tricalcium phosphate and colloidal cerium oxide are particularly preferable from the viewpoint of stably obtaining the intended resin particles.

The amount of the dispersion stabilizer to be added is preferably from 0.5 to 15% by weight based on the thermoplastic resin. The amount added may be 0.5% by weight, 0.7% by weight, 1.0% by weight, 1.2% by weight, 1.5% by weight, 3% by weight, 5% by weight, and 8 weights. Amounts %, 10% by weight, and 15% by weight.

Further, in the method of the present invention, in addition to the above-mentioned dispersion stabilizer, a surfactant such as an anionic surfactant, a cationic surfactant, a two-ionic surfactant, or a nonionic surfactant may be used in combination.

The anionic surfactants include fatty acid oils such as sodium oleate and castor oil; alkyl sulfates such as sodium lauryl sulfate and ammonium lauryl sulfate; and alkylbenzenes such as sodium dodecylbenzenesulfonate. Sulfonate; alkylnaphthalenesulfonate, alkanesulfonate, dialkylsulfosuccinate, alkyl phosphate, naphthalenesulfonic acid formaldehyde condensate, polyoxyethylene ethyl phenyl ether sulfate Salt and polyoxyalkylene ethyl sulfonate and the like. The nonionic surfactants are: polyoxyethylene ethyl ether, polyoxyethylene ethyl phenyl ether, polyoxyethyl alcohol ester, sorbitan fatty acid ester, polysorbate A fatty acid ester, a polyoxyethylene ethylamine, a glycerin fatty acid ester, an oxyethylene-oxypropylene block polymer, or the like. The cationic surfactants include alkylamine salts such as laurylamine acetate and stearylamine acetate; and quaternary ammonium salts such as lauryl trimethylammonium chloride. The two-ionic surfactant is a lauryl dimethylamine oxide or the like.

The amount of the surfactant added is preferably 0.01 to 0.5% by weight based on the water.

The dispersion stabilizer or the surfactant is used in consideration of the particle size and dispersion stability of the obtained resin particles, and the selection, the combination, the amount of use, and the like are appropriately adjusted.

(iii) Water usage

The amount of water used is 100% by weight based on 100 parts by weight of the thermoplastic resin. It is preferably 2200 parts by weight. When the amount used is less than 100 parts by weight, the concentration of the thermoplastic resin may be too high, and it may be difficult to sufficiently stir. When it is more than 2200 parts by weight, the yield may be small with respect to the size of the device. The amount of water used may be 100 parts by weight, 150 parts by weight, 200 parts by weight, 300 parts by weight, 600 parts by weight, 800 parts by weight, 1000 parts by weight, 1500 parts by weight, 2000 parts by weight, and 2200 parts by weight. It is preferably used in an amount of from 150 to 1,000 parts by weight, more preferably from 200 to 800 parts by weight.

(iv) heating and stirring

The heating and stirring is carried out at a heating temperature of 100 ° C or higher. When the heating temperature is less than 100 ° C, the thermoplastic resin does not soften and may not be microparticulated. Heating and stirring can be carried out at a temperature of 180 ° C or lower. The heating temperature may be 100 ° C, 120 ° C, 140 ° C, 160 ° C and 180 ° C.

The substantially spherical particles obtained by the present production method are particles having a small particle size distribution, because an extremely uniform emulsion can be obtained in the stage of emulsion formation. Therefore, in order to obtain a sufficient shear force to form an emulsion, a conventional method such as a liquid phase stirring method in which a blade is stirred, a mixing method by a homogenizer, and an ultrasonic irradiation method can be used. Mix.

The stirring speed and time are not particularly limited as long as the thermoplastic resin is soluble in the solvent or uniformly dispersed in the solvent, and is preferably selected as appropriate.

Heating and stirring are generally carried out under atmospheric pressure, but may be carried out under reduced pressure or under pressure as needed.

(b) Cooling step

In order to precipitate the thermoplastic resin into particles, the solvent containing the thermoplastic resin is cooled by heating and stirring. The cooling temperature is generally normal temperature (about 25 ° C). The time from the temperature at which the stirring is heated to the cooling temperature is preferably as fast as possible. Moreover, it is preferred that the cooling system be stirred at the same time. The stirring speed can be set in the same range as the stirring speed at the time of heating and stirring.

The substantially spherical particles in the cooled solvent can be removed from the solvent after filtration, dehydration, and drying as needed. Filtration, dehydration, and drying are not particularly limited and can be carried out by a conventional method.

[Examples]

Hereinafter, the present invention will be specifically described by way of examples, but the invention is not limited thereto. First, the measurement methods and evaluation methods in the examples and comparative examples will be described.

(Measurement of true sphericity)

The measurement was carried out using a flow type particle image analyzer (trade name "FPIA (registered trademark) - 3000S", manufactured by Sysmex Corporation).

In the specific measurement method, a surfactant as a dispersing agent is added to 20 mL of ion-exchanged water, and preferably 0.05 g of an alkylbenzenesulfonate is used to obtain an aqueous surfactant solution. Then, 0.2 g of the resin particle group to be measured was added to the surfactant aqueous solution, and an ultrasonic dispersion machine "BRANSON SONIFIER 450" (output power: 400 W, frequency: 20 kHz) manufactured by BRANSON Co., Ltd. as a disperser was used. The sound wave was irradiated for 5 minutes, and dispersion treatment was performed by dispersing the resin particle group in the surfactant aqueous solution to obtain a dispersion liquid for measurement.

The measurement system uses the above-mentioned flow type particles equipped with a standard objective lens (10 times) For the analyzer, the sheath liquid used in the above-described flow type particle image analyzer is a particle sheath (trade name "PSE-900A", manufactured by Sysmex Corporation). The dispersion for measurement adjusted in accordance with the above procedure was introduced into the flow type particle image analyzer, and was measured under the following measurement conditions.

Measurement mode: HPF measurement mode

Particle size measurement range: 2.954μm to 30.45μm

The true sphericity of the particle is measured from 0.5 to 1.0.

Number of particles measured: 1000

In the measurement, a suspension of a standard polymer particle group (for example, "5200A" manufactured by Thermo Fisher Scientific Co., Ltd. (standard polystyrene particle group diluted with ion-exchanged water)) is used before the measurement is started, and the above-mentioned flow type granule is used. Like the analyzer's automatic focus adjustment. Further, the true sphericity is a value obtained by dividing the circumference calculated by the diameter of the true circle having the same projected area as that of the image of the resin particle by the circumference of the image of the resin particle.

(Measurement of volume average particle size and coefficient of variation (CV value))

‧ Coulter counting

The volume average particle diameter of the resin particles was measured using a Coulter Multisizer ^TM 3 (measuring device manufactured by Beckman Coulter Co., Ltd.). The pore diameter was measured using a calibrated based Beckman Coulter, Inc. issued by Coulter Multisizer ^TM 3 User manual implementer.

Further, the pore diameter used in the measurement is appropriately selected depending on the size of the resin particles to be measured. It is suitably carried out as follows: when the measured volume average particle diameter of the resin particles is 1 μm or more and 10 μm or less, a pore diameter of 50 μm or the measured resin particles is selected. When the volume average particle diameter of the hypothesis is larger than 10 μm and the pore diameter of 100 μm or less is selected, the volume average particle diameter of the resin particles is larger than 30 μm and below 90 μm, the pore diameter of 280 μm is selected, and the resin particles are selected. When the volume average particle diameter is more than 90 μm and is 150 μm or less, a pore diameter or the like having a size of 400 μm is selected. When the volume average particle diameter after the measurement differs from the assumed volume average particle diameter, it is changed to a pore size having an appropriate size, and the measurement is performed again.

The current (hole current) and the gain are appropriately set depending on the selected aperture size. For example, when selecting an aperture having a size of 50 μm, the current (hole current) is set to -800, and the gain is set to 4; when an aperture having a size of 100 μm is selected, the current (hole current) is set to -1600, the gain is set to 2; when an aperture having a size of 280 μm and 400 μm is selected, the current (hole current) is set to -3200, and the gain is set to 1.

For the measurement sample, 0.1 g of the resin particles were used in a 10% by weight aqueous solution of 0.1% by weight of a nonionic surfactant aqueous solution (manufactured by Daiwa Scientific Co., Ltd.; "TOUCHMIXER MT-31") and an ultrasonic cleaning machine (VELVO). - "CLEAR company"; "ULTRASONIC CLEANER VS-150") to disperse the resulting dispersion. During the measurement, the bubbles were slowly stirred in the beaker so that the bubbles did not enter, and when the resin particles were measured at 100,000, the measurement was terminated. The volume average particle diameter of the resin particles is an arithmetic mean value in the particle size distribution based on the volume basis of 100,000 resin particles.

The coefficient of variation (CV value) of the particle diameter of the resin particles is obtained by the following Learn formula calculations.

The coefficient of variation (CV value) of the particle diameter of the resin particles = (the standard deviation of the particle size distribution based on the volume of the resin particles, the volume average particle diameter of the resin particles) × 100

(Measurement of oil absorption of linseed oil)

The oil absorption of the linseed oil of the resin particles is determined by referring to the method of JIS K 5101-13-2-2004, and the refined linseed oil is used instead of the boiled linseed oil, and the judgment is based on the determination of the end point (change to "the assay plate stands vertically At the time, the paste (the kneaded material of the resin particles and the produced linseed oil) starts to flow. The content of the oil absorption of linseed oil is as follows.

(A) devices and apparatus

Measuring plate: smooth glass plate larger than 300 × 400 × 5 mm

Palette knife (scraper): a handle with a steel or stainless steel blade

Chemical balance (counter): up to 100mg level

Burette: The capacity of 10 mL according to JIS R 3505:1994

(B) reagent

Refined linseed oil: ISO 150:1980 (this time uses a linseed oil (made by Wako Pure Chemical Industries, Ltd.))

(C) Determination method

(1) The resin particles 1g were taken in the center of the measuring plate, and 4 or 5 drops of refined linseed oil were dropped from the burette every time, and slowly dropped in the center of the resin particles, and the resin particles and the refined linseed were each time. The oil is thoroughly mixed with a palette knife.

(2) Repeat the above-mentioned dripping and mixing operations, when resin particles and fine When the whole linseed oil becomes a hard putty-like block, it is mixed with one drop, and when the last drop of refined linseed oil is dropped, the paste (the mixture of resin particles and refined linseed oil) softens rapidly. Take the point of starting to flow as the end point.

(3) Judgment of flow

By the dropwise addition of the last drop of refined linseed oil, the paste softens rapidly, and when the measuring plate stands vertically, the paste starts to move, and it is judged that the paste is flowing. When the assay plate stands vertically, one drop of refined linseed oil can be added in the case of a paste.

(4) The consumption amount of the refined linseed oil at the time of reaching the end point is read as the decrease amount of the liquid amount in the burette.

(5) The measurement time of one time is performed within 7 to 15 minutes, and the measurement time is measured again when it exceeds 15 minutes, and the value at the time of completion of measurement in a predetermined time is used.

(D) Calculation of oil absorption of linseed oil

The linseed oil absorption per 100 g of the sample was calculated by the following formula.

O=(V/m)×100

Here, O: linseed oil absorption (mL / 100g), m: weight of resin particles (g), V: capacity of purified linseed oil consumed (mL)

(Measurement of light scattering index)

(i) Determination of reflected photometric distribution

The diffusivity of light reflected on the surface of the resin particles was evaluated by the method shown below.

Reflective photometric distribution of resin particles using a three-dimensional photometer (village coloring) The variable angle photometer GP-200 manufactured by Caishen Research Co., Ltd. was measured at room temperature of 20 ° C and a relative humidity of 65%.

Specifically, it includes:

(1) As shown in Fig. 1, a double-sided tape (ORT-1, manufactured by Nitto Denko Corporation), which is cut into squares of 2 cm on each side, is attached to the center of a black ABS resin sheet (manufactured by Takiron Co., Ltd.) 4 having a thickness of 2 mm. .

(2) Next, on the adhesive surface of the double-sided tape 3 on the black portion of the black ABS resin sheet 4, resin pellets were obtained using an apparent density measuring device funnel and a funnel table (JIS K5101-12-1-2004). 2, the excess resin particles 2 on the adhesive surface are blown off with a compressed air of 0.05 to 0.1 MPa.

(3) The black ABS resin sheet 4 was placed on a flat glass plate, and another 500 g of a square plate having a square shape of 5 cm on each side was placed on the drip surface of the resin particles 2, and the load was added to the resin particles 2. Allow to stand for 1 minute. Then, excess resin particles on the above-mentioned adhesive surface are blown off by compressed air.

(4) A test piece in which the operations of (2) and (3) were repeated three times was used as the test piece 1 for measuring the reflected illuminance distribution. Then, the reflected light of the obtained test piece 1 was measured in the following manner. As shown in Fig. 1, the light 5 having a halogen lamp as a light source is incident on the test piece 1 at an angle of -45° with respect to the normal line (0°) of the test piece 1 (resin particle 2) (resin particle 2) The luminosity distribution in the reflection angle of the reflected reflected light 6 from -90° to +90° is measured by a three-dimensional photometer. At the time of measurement, the position of the test piece 1 was adjusted so that all incident light was incident on the black portion of the test piece 1. In addition, the reflected light detection is detected by a photomultiplier tube having a spectral sensitivity of 185 to 850 nm and a maximum sensitivity of 530 nm.

(ii) Calculation of reflected light intensity relative to +45° reflected light intensity of 100°

The reflected light intensity data (peak luminosity data) in the reflection angles of 0° and +45° obtained by the measurement of the reflected illuminance distribution, and the reflection light intensity (peak luminosity) of the reflection angle +45° is 100, and the reflection is obtained. Reflected light intensity (peak luminosity) in the angle 0°. When the reflected light intensity of the reflection angle +45° (mirror reflection direction) is 100, the intensity of the reflected light with a reflection angle of 0° is closer to 100, and the soft focus effect when blending in the cosmetic material is larger. The light scattering index is calculated according to the following formula.

Light scattering index = (scattered light intensity of 0°) / (scattered light intensity of 45°)

The closer the value is displayed, the higher the scattering characteristic regardless of the angle.

(Example 1)

In a 300 mL autoclave, 20 g of polybutyl succinate (GS-Pla _{(R) part} number: FZ71PD) manufactured by Mitsubishi Chemical Corporation, and 3-methoxy-3-methyl as a solvent were charged as a thermoplastic resin. 1-butanol (Sol fit Fine grade manufactured by Kuraray Co., Ltd.) 60 g, 100 g of ion-exchanged water, 10% of a tertiary calcium phosphate aqueous solution (TCP-10U manufactured by Pacific Chemical Industry Co., Ltd.) as a dispersing agent, and 20 g as a surfactant 0.24 g of sodium lauryl sulfate was stirred at a reaction temperature (heating and stirring temperature) of 120 ° C and a stirring speed of 400 rpm for 90 minutes.

Then, after quenching at a stirring speed (down to 25 ° C in 30 minutes), the contents were taken out. The contents were dehydrated, filtered, and dried to obtain substantially spherical particles.

(Example 2)

In a 300 mL autoclave, 20 g of polybutyl succinate (GS-Pla _{(R) part} number: FZ71PD) manufactured by Mitsubishi Chemical Corporation, and 3-methoxy-3-methyl as a solvent were charged. 60-g-butanol (Sol fit Fine grade manufactured by Kuraray Co., Ltd.), 120 g of ion-exchanged water, and hydrophobic fumed silica as a dispersing agent (AEROSIL _(R) R972, manufactured by Aerosil Corporation, Japan) 1.5 g dispersed mixture. After the introduction, the mixture was stirred at a reaction temperature of 120 ° C and a stirring speed of 400 rpm for 90 minutes.

Then, after quenching at a stirring speed (down to 25 ° C in 30 minutes), the contents were taken out. The contents were dehydrated, filtered, and dried to obtain substantially spherical particles.

(Example 3)

In a 300 mL autoclave, 40 g of polybutyl succinate (GS-Pla _{(R) part} number: FZ71PD) manufactured by Mitsubishi Chemical Corporation, and 3-methoxy-3-methyl as a solvent were charged. 60-g of 1-butanol (Solfit Fine grade manufactured by Kuraray Co., Ltd.), 100 g of ion-exchanged water, and 3 g of a dispersion of hydrophobic fumed cerium oxide (AEROSIL _(R) R972, manufactured by Aerosil Corporation, Japan ₎ as a dispersing agent Solution. After the introduction, the mixture was stirred at a reaction temperature of 120 ° C and a stirring speed of 400 rpm for 90 minutes.

Then, after quenching at a stirring speed (down to 25 ° C in 30 minutes), the contents were taken out. The contents were dehydrated, filtered, and dried to obtain substantially spherical particles.

(Example 4)

In a 300 mL autoclave, 20 g of polybutyl succinate (GS-Pla _{(R) part} number: FZ71PD) manufactured by Mitsubishi Chemical Corporation, and 3-methoxy-3-methyl as a solvent were charged. Base-1-butanol (Sol fit Fine grade manufactured by Kuraray Co., Ltd.) 60 g, ion-exchanged water 120 g, polyoxyethylidene styrenated phenol ether as a surfactant (manufactured by First Industrial Pharmaceutical Co., Ltd.; product name: Noigen EA-167) 0.12 g and a mixed solution of a hydrophobic fumed cerium oxide (AEROSIL _(R) R972 manufactured by Aerosil Co., Ltd., Japan, 1.5 g ₎ as a dispersing agent. After the introduction, the mixture was stirred at a reaction temperature of 120 ° C and a stirring speed of 400 rpm for 90 minutes.

Then, after quenching at a stirring speed (down to 25 ° C in 30 minutes), the contents were taken out. The contents were dehydrated, filtered, and dried to obtain substantially spherical particles.

(Example 5)

In a 1500 mL autoclave, 120 g of polybutyl succinate (GS-Pla _{(R) part} number: FZ71PD) manufactured by Mitsubishi Chemical Corporation, and 3-methoxy-3-methyl as a solvent were charged. 360-gram of 1-butanol (Sol Fit Fine grade manufactured by Kuraray Co., Ltd.), 720 g of ion-exchanged water, and 6 g of a dispersion of hydrophobic fumed cerium oxide (AEROSIL _(R) R972, manufactured by Aerosil Corporation, Japan ₎ as a dispersing agent Solution. After the introduction, the mixture was stirred at a reaction temperature of 120 ° C and a stirring speed of 400 rpm for 90 minutes.

Then, after quenching at a stirring speed (down to 25 ° C in 30 minutes), the contents were taken out. The contents were dehydrated, filtered, and dried to obtain substantially spherical particles.

(Example 6)

In a 1500 mL autoclave, 240 g of polybutyl succinate (GS-Pla _{(R) part} number: FZ71PD) manufactured by Mitsubishi Chemical Corporation, and 3-methoxy-3-methyl as a solvent were charged. 1-4 g of 1-butanol (Sol fit Fine grade manufactured by Kuraray Co., Ltd.), 540 g of ion-exchanged water, and a dispersion of hydrophobic gas phase ruthenium dioxide (AEROSIL _(R) R972 manufactured by Aerosil Co., Ltd., Japan, 18 g) dispersed as a dispersant Solution. After the introduction, the mixture was stirred at a reaction temperature of 120 ° C and a stirring speed of 600 rpm for 90 minutes.

Then, after quenching at a stirring speed (down to 25 ° C in 30 minutes), the contents were taken out. The contents were dehydrated, filtered, and dried to obtain substantially spherical particles.

(Example 7)

In a 1500 mL autoclave, 240 g of polybutyl succinate (GS-Pla _{(R) part} number: FZ71PD) manufactured by Mitsubishi Chemical Corporation, and 3-methoxy-3-methyl as a solvent were charged. Benzyl-1-butanol (Solfit Fine grade manufactured by Kuraray Co., Ltd.) 480 g, ion exchange water 480 g, and hydrophobic gas phase ruthenium dioxide (AEROSIL _(R) R972 manufactured by Aerosil Corporation, Japan) as a dispersant Solution. After the introduction, the mixture was stirred at a reaction temperature of 120 ° C and a stirring speed of 600 rpm for 90 minutes.

Then, after quenching at a stirring speed (down to 25 ° C in 30 minutes), the contents were taken out. The contents were dehydrated, filtered, and dried to obtain substantially spherical particles.

(Example 8)

In a 1500 mL autoclave, 240 g of polybutyl succinate (GS-Pla _{(R) part} number: FZ71PD) manufactured by Mitsubishi Chemical Corporation, and 3-methoxy-3-methyl as a solvent were charged. 1,4-g-butanol (Sol Fit Fine grade by Kuraray Co., Ltd.) 480 g, ion-exchanged water 480 g, and a hydrophobic gas phase cerium oxide (AEROSIL _(R) R972, manufactured by Aerosil Corporation, Japan) dispersed as a dispersing agent Solution. After the introduction, the mixture was stirred at a reaction temperature of 120 ° C and a stirring speed of 600 rpm for 90 minutes.

Then, after quenching at a stirring speed (down to 25 ° C in 30 minutes), the contents were taken out. The contents were dehydrated, filtered, and dried to obtain substantially spherical particles.

(Example 9)

In a 1500 mL autoclave, polybutylene succinate (GS-Pla _{(R) part} number: FZ71PD) manufactured by Mitsubishi Chemical Corporation, 240 g, and 3-methoxy-3-methyl as a solvent were charged. 1,4-butanol (Sol fit Fine grade manufactured by Kuraray Co., Ltd.) 480 g, ion-exchanged water 240 g, 10% aqueous calcium phosphate solution (TCP-10U manufactured by Pacific Chemical Industry Co., Ltd.) as a dispersing agent, 240 g, and as a surfactant 0.48 g of sodium lauryl sulfate was stirred at a reaction temperature (heating and stirring temperature) of 120 ° C and a stirring speed of 600 rpm for 90 minutes.

Then, after quenching at a stirring speed (down to 25 ° C in 30 minutes), the contents were taken out. The contents were dehydrated, filtered, and dried to obtain substantially spherical particles.

(Embodiment 10)

In a 1500 mL autoclave, 240 g of polylactic acid (TERRAMAC _{(R) part} number: TE-2500) manufactured by Unitika Co., Ltd., and 3-methoxy-3-methyl-1-butanol as a solvent were charged. (Sol fit Fine grade manufactured by Kuraray Co., Ltd.) 480 g, 480 g of ion-exchanged water, and a mixed solution of a hydrophobic fumed cerium oxide (AEROSIL _(R) R972, manufactured by Nippon Aerosil Co., Ltd. ₎ as a dispersing agent, 18 g. After the introduction, the mixture was stirred at a reaction temperature of 140 ° C and a stirring speed of 600 rpm for 90 minutes.

Then, after quenching at a stirring speed (down to 25 ° C in 30 minutes), the contents were taken out. The contents were dehydrated, filtered, and dried to obtain substantially spherical particles.

(Example 11)

In a 1500 mL autoclave, a copolymer of 3-hydroxybutyrate/3-hydroxyhexanoate as a thermoplastic resin (KANEKA Biopolymer AONILEX _{(R) part} number: X131A) manufactured by Kaneka Co., Ltd. was charged as a solvent 3 -methoxy-3-methyl-1-butanol (Sol fit Fine grade by Kuraray Co., Ltd.) 480 g, ion-exchanged water 480 g, and hydrophobic fumed cerium oxide as a dispersing agent (AEROSIL ₍ made by Japan Aerosil Co., Ltd.) _R) R972) 24 g of a dispersed mixed solution. After the introduction, the mixture was stirred at a reaction temperature of 130 ° C and a stirring speed of 600 rpm for 90 minutes.

Then, after quenching at a stirring speed (down to 25 ° C in 30 minutes), the contents were taken out. The contents were dehydrated, filtered, and dried to obtain substantially spherical particles.

(Comparative Example 1)

Various measurements were carried out using Ganz Pearl GMX-0810 manufactured by Aica Industries.

(Comparative Example 2)

In a 300 mL autoclave, 20 g of polybutyl succinate (GS-Pla _{(R) part} number: FZ71PD) manufactured by Mitsubishi Chemical Corporation, and 3-methoxy-3-methyl as a solvent were charged. 60-g-butanol (Sol fit Fine grade manufactured by Kuraray Co., Ltd.), 120 g of ion-exchanged water, and hydrophobic fumed silica as a dispersing agent (AEROSIL _(R) R972, manufactured by Aerosil Corporation, Japan) 1.5 g dispersed mixture. After the introduction, the mixture was stirred at a reaction temperature of 90 ° C and a stirring speed of 400 rpm for 90 minutes.

Then, after quenching at a stirring speed (down to 25 ° C in 30 minutes), when the contents were taken out, the pellets were still in a particle shape and could not be micronized.

The various physical properties of the substantially spherical particles obtained in the examples are shown in the following table.

The substantially spherical particles obtained in the examples are obtained by using a specific solvent, and the thermoplastic resin is heated and stirred at a temperature of 100 ° C or higher and then cooled, and thus is spherical, and has a small particle size and a particle size distribution. It is narrow and it is known that it has high light scattering properties.

Claims (6)

A substantially spherical resin particle composed of a thermoplastic resin having a true sphericity of 0.90 to 1.00, a light scattering index of 0.5 to 1.0, and a linseed oil absorption of 30 to 150 ml/100 g, wherein the above thermoplastic resin Selected from polyethylene, polypropylene, ethylene/vinyl acetate copolymer, ethylene/(meth)acrylic acid copolymer, ethylene/(meth)acrylate copolymer, polybutylene succinate, polyhydroxyalkanoic acid At least one resin of the group consisting of ester, polycaprolactam, nylon 12 and nylon 6. The substantially spherical resin particle composed of a thermoplastic resin according to the first aspect of the invention, wherein the thermoplastic resin is a biodegradable resin. The substantially spherical resin particle composed of a thermoplastic resin according to the first aspect of the invention, wherein the thermoplastic resin is based on 3-alkoxy-3-methyl-1-butanol and/or 3 a resin in which alkoxy-3-methyl-1-butyl acetate is dissolved or plasticizable at 100 ° C or higher and is insoluble at normal temperature, wherein the alkoxy group has 1 to 5 carbon atoms. A method for producing a substantially spherical resin particle composed of a thermoplastic resin, wherein the substantially spherical resin particle composed of a thermoplastic resin according to the first aspect of the invention is a 3-alkoxy group. In the presence of a solvent, water and a dispersion stabilizer of -3-methyl-1-butanol and/or 3-alkoxy-3-methyl-1-butyl acetate, the thermoplastic resin is at 100 ° C or higher. The temperature is emulsified, dispersed, and then cooled, wherein the alkoxy group has 1 to 5 carbon atoms. A cosmetic material which is prepared by blending a substantially spherical resin particle composed of a thermoplastic resin as described in claim 1 of the patent application. A coating material prepared by blending substantially spherical resin particles composed of a thermoplastic resin as described in claim 1 of the patent application.