JP2006342314A - Process for production of organic particles and unit for production thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for stably producing organic particles in an industrial scale by reprecipitation method and to provide an apparatus for the same. <P>SOLUTION: The invention relates to the method for the production of organic particles by mixing a solution of an organic material in a good solvent with a poor solvent for the organic material which solvent is compatible with the good solvent to form particles of the organic material, wherein the organic particles is formed by feeding the organic material dissolved in the good solvent to the poor solvent filled in a mixing chamber installed in a vessel containing the poor solvent, and stirring with stirring means installed in the mixing chamber. The invention relates to the units for the production of organic particles comprising the vessel for storing the poor solvent, the mixing chamber capable of filling with the poor solvent, and stirring means installed in the mixing chamber and mixing the solution of the organic material fed into the mixing chamber with the poor solvent. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing organic particles by a reprecipitation method and a production apparatus used therefor. Furthermore, the present invention relates to a method capable of stably mass-producing organic particles by a reprecipitation method and a manufacturing apparatus used therefor.

In recent years, efforts have been made to reduce the size of particles. In particular, research is being carried out to reduce the size to nanometer size (for example, in the range of 10 to 100 nm), which is difficult to produce by a pulverization method or the like. Furthermore, attempts have been made to reduce the size to nanometer size and to make monodispersed particles.
The size of such nanometer-sized fine particles is different from larger bulk particles, smaller molecules and atoms, and is located in the middle. Therefore, it has been pointed out that new characteristics that could not be predicted in the past can be extracted. Moreover, if this can be made monodisperse, its characteristics can be stabilized. The potential of such nanoparticles is expected in various fields, and research is being actively conducted in a wide range of fields such as biochemistry, new materials, electronic devices, light-emitting display devices, printing, and medicine.
In particular, organic nanoparticles made of an organic compound have a high potential as a functional material because the organic compound itself has diversity. For example, polyimide is used in many fields because it is a chemically and mechanically stable material such as heat resistance, solvent resistance, and mechanical properties, and has excellent electrical insulation. The use of polyimide in fine particles is expanding its new use due to the combination of polyimide characteristics and shape. For example, as a proposed technique for using finely divided polyimide, it has been proposed to use an additive for powder toner for image formation (Patent Document 1).

Also, regarding organic pigments among organic nanoparticles, for example, paints, printing inks, electrophotographic toners, ink-jet inks, color filters, etc. can be cited as applications, and now important in life. It has become a compound. Particularly, high performance is required, and pigments for inkjet inks and color filter pigments are particularly important in practical use.
Conventionally, dyes have been used for coloring materials for ink jet inks, but there are problems in terms of water resistance and light resistance, and pigments have come to be used to improve them. An image obtained with the pigment ink has an advantage of being excellent in light resistance and water resistance as compared with an image obtained with a dye-based ink. However, it is difficult to uniformly fine and monodisperse nanometer size that can penetrate into the voids on the paper surface, and there is a problem that the adhesion to paper is inferior.
In addition, with the increase in the number of pixels of a digital camera, it is desired to reduce the thickness of color filters used for optical elements such as CCD sensors and display elements. An organic pigment is used for the color filter. However, since the thickness of the filter greatly depends on the particle diameter of the organic pigment, it is desired to produce fine particles having a nanometer size level and being monodispersed and stable.

Regarding the production of organic particles, the gas phase method (a method in which a sample is sublimated in an inert gas atmosphere and the particles are recovered on a substrate), the liquid phase method (for example, a sample dissolved in a good solvent under stirring conditions and temperature). Reprecipitation method to obtain fine particles by injecting into a controlled poor solvent), laser ablation method (method of refining particles by ablating by irradiating laser to sample dispersed in solution), etc. ing. In addition, production examples in which monodispersion with a desired size is attempted by these methods have been reported.
Among them, the reprecipitation method is attracting attention as a method for producing organic particles excellent in simplicity and productivity (see Patent Documents 2 and 3).

  However, the reprecipitation method has a problem that although the organic particles can be produced even at room temperature, the particle size has a large temperature dependency. In particular, for stable production of organic pigment particles, it is necessary to sufficiently cool the poor solvent, and for industrial mass production, a cooling plant is required, resulting in a significant increase in cost. Therefore, there has been a demand for a method for producing organic fine particles stably near room temperature, which is relatively easy to control the temperature.

  On the other hand, an example of an industrial grain forming apparatus is a silver halide grain manufacturing apparatus (Patent Document 4). However, this apparatus produces silver halide grains by metathesis reaction of a water-soluble silver salt solution and a water-soluble halide solution, and there is no application example in which organic fine particles are precipitated.

JP-A-11-237760 JP-A-6-79168 JP 2004-91560 A Japanese Patent Publication No. 55-10545

  An object of this invention is to provide the method of manufacturing a favorable organic particle by a reprecipitation method, and the manufacturing apparatus used therefor. More specifically, an object of the present invention is to provide a method capable of stably producing organic particles on an industrial scale by a reprecipitation method and a manufacturing apparatus used therefor.

The above problems have been achieved by the following means.
(1) A method for producing organic particles, in which a solution of an organic material dissolved in a good solvent and a poor solvent of the organic material compatible with the good solvent are mixed to form the organic material as particles, An organic material dissolved in the good solvent is supplied into a mixing chamber filled with the poor solvent, and the mixture is stirred by a stirring means provided in the mixing chamber. A method for producing organic particles, comprising:
(2) The stirring means has a first stirring means and a second stirring means, and the poor solvent and the good solvent are rapidly mixed in the mixing chamber by the first stirring means, and generated by the second stirring means. The method for producing organic particles according to item (1), wherein the organic particles are immediately discharged out of the mixing chamber.
(3) Item (1) or (2), wherein the poor solvent of the organic material is an aqueous solvent, an alcohol solvent, a ketone solvent, an ether solvent, an ester solvent or a mixed solvent thereof. The manufacturing method of the organic particle as described in any one of.
(4) The good solvent of the organic material is an aqueous solvent, an alcohol solvent, a ketone solvent, an ether solvent, a sulfoxide solvent, an ester solvent, an amide solvent or a mixed solvent thereof. (1) The manufacturing method of the organic particle of any one of (3).
(5) The method for producing organic particles according to any one of (1) to (4), wherein the organic material is an organic pigment.
(6) The method for producing organic particles according to any one of (1) to (5), wherein the number average particle diameter of the organic particles is 1 μm or less.
(7) A device for producing organic particles, in which a solution of an organic material dissolved in a good solvent and a poor solvent of the organic material compatible with the good solvent are mixed to form the organic material as particles, A container capable of containing a poor solvent, a mixing chamber provided in the container and capable of filling the poor solvent therein, and provided in the mixing chamber and supplied to the mixing chamber, An apparatus for producing organic particles, comprising a stirring means for mixing and stirring the organic material solution and the poor solvent.
(8) It has a first stirring means for rapidly mixing the poor solvent and the good solvent inside the mixing chamber, and a second stirring means for immediately discharging the generated organic particles to the outside of the mixing chamber. The apparatus for producing organic particles according to (7).
(9) The apparatus for producing organic particles according to (7) or (8), wherein the number average particle diameter of the organic particles is 1 μm or less.

  According to the method for producing organic particles of the present invention and the production apparatus used therefor, it is possible to provide a production method and apparatus suitable for production on an industrial scale, in which the temperature dependence of the particle size in the vicinity of room temperature is small. . Moreover, it is possible to produce organic particles suitable for color filter coating liquids and ink-jet inks on an industrial scale.

  A preferred embodiment of the present invention is a method for producing organic particles in which a solution of an organic material dissolved in a good solvent and a poor solvent of the organic material compatible with the solvent are mixed to form the organic material as particles. The organic material dissolved in the good solvent is supplied into the mixing chamber provided as if the poor solvent is filled in the container filled with the poor solvent, and provided in the mixing chamber. It is the manufacturing method of the organic particle manufactured, stirring with a stirring means. Another preferred embodiment is the production of organic particles in which a solution of an organic material dissolved in a good solvent and a poor solvent of the organic material compatible with the good solvent are mixed to form the organic material as particles. An apparatus, a container capable of filling the poor solvent, a mixing chamber provided in the container and capable of filling the poor solvent therein, a mixing chamber provided in the mixing chamber, and the mixing chamber It is the organic particle manufacturing apparatus provided with the stirring means which mixes and stirs the solution of the said organic material supplied to and the said poor solvent. Hereinafter, the production method and apparatus of the present invention will be described in detail.

  The particles formed by the production method of the present invention may be crystalline particles, amorphous particles, or a mixture thereof.

  The organic material produced in the present invention is not particularly limited as long as it can be produced by a reprecipitation method and can be formed as particles. Examples of the organic material include organic pigments, organic dyes, fullerenes, polydiacetylenes, polyimides and other high molecular compounds, aromatic hydrocarbons or aliphatic hydrocarbons (eg, aromatic hydrocarbons or aliphatic hydrocarbons having orientation). Or an aromatic or aliphatic hydrocarbon having a sublimation property), an organic pigment, an organic dye, or a polymer compound is preferable, and an organic pigment is more preferable. A combination of these may also be used.

  The organic pigment that can be used in the method for producing organic particles of the present invention is not limited in terms of hue. For example, perylene, perinone, quinacridone, quinacridonequinone, anthraquinone, anthanthrone, benzimidazolone, disazo condensation, Disazo, azo, indanthrone, phthalocyanine, triarylcarbonium, dioxazine, aminoanthraquinone, diketopyrrolopyrrole, thioindigo, isoindoline, isoindolinone, pyranthrone or isoviolanthrone pigment, or a mixture thereof. .

More specifically, for example, C.I. I. Pigment red 190 (C.I. No. 71140), C.I. I. Pigment red 224 (C.I. No. 71127), C.I. I. Perylene pigments such as CI Pigment Violet 29 (C.I. No. 71129); I. Pigment orange 43 (C.I. No. 71105), or C.I. I. Perinone pigments such as CI Pigment Red 194 (C.I. No. 71100); I. Pigment violet 19 (C.I. No. 73900), C.I. I. Pigment violet 42, C.I. I. Pigment red 122 (C.I. No. 73915), C.I. I. Pigment red 192, C.I. I. Pigment red 202 (C.I. No. 73907), C.I. I. Pigment Red 207 (C.I. No. 73900, 73906) or C.I. I. Pigment Red 209 (C.I. No. 73905), a quinacridone pigment, C.I. I. Pigment red 206 (C.I. No. 73900/73920), C.I. I. Pigment orange 48 (C.I. No. 73900/73920), or C.I. I. Quinacridone quinone pigments such as CI Pigment Orange 49 (C.I. No. 73900/73920); I. Anthraquinone pigments such as CI Pigment Yellow 147 (C.I. No. 60645); I. Anthanthrone pigments such as CI Pigment Red 168 (C.I. No. 59300); I. Pigment brown 25 (C.I. No. 12510), C.I. I. Pigment violet 32 (C.I. No. 12517), C.I. I. Pigment yellow 180 (C.I. No. 21290), C.I. I. Pigment yellow 181 (C.I. No. 11777), C.I. I. Pigment orange 62 (C.I. No. 11775), or C.I. I. Benzimidazolone pigments such as CI Pigment Red 185 (C.I. No. 12516); I. Pigment yellow 93 (C.I. No. 20710), C.I. I. Pigment yellow 94 (C.I. No. 20038), C.I. I. Pigment yellow 95 (C.I. No. 20034), C.I. I. Pigment yellow 128 (C.I. No. 20037), C.I. I. Pigment yellow 166 (C.I. No. 20035), C.I. I. Pigment orange 34 (C.I. No. 21115), C.I. I. Pigment orange 13 (C.I. No. 21110), C.I. I. Pigment orange 31 (C.I. No. 20050), C.I. I. Pigment red 144 (C.I. No. 20735), C.I. I. Pigment red 166 (C.I. No. 20730), C.I. I. Pigment red 220 (C.I. No. 20055), C.I. I. Pigment red 221 (C.I. No. 20065), C.I. I. Pigment red 242 (C.I. No. 20067), C.I. I. Pigment red 248, C.I. I. Pigment red 262, or C.I. I. Disazo condensation pigments such as CI Pigment Brown 23 (C.I. No. 20060); I. Pigment yellow 13 (C.I. No. 21100), C.I. I. Pigment yellow 83 (C.I. No. 21108), or C.I. I. Disazo pigments such as CI Pigment Yellow 188 (C.I. No. 21094); I. Pigment red 187 (C.I. No. 12486), C.I. I. Pigment red 170 (C.I. No. 12475), C.I. I. Pigment yellow 74 (C.I. No. 11714), C.I. I. Pigment yellow 150 (C.I. No. 48545), C.I. I. Pigment red 48 (C.I. No. 15865), C.I. I. Pigment red 53 (C.I. No. 15585), C.I. I. Pigment orange 64 (C.I. No. 12760), or C.I. I. Azo pigments such as C.I. Pigment Red 247 (C.I. No. 15915), C.I. I. Indanthrone pigments such as CI Pigment Blue 60 (C.I. No. 69800); I. Pigment green 7 (C.I. No. 74260), C.I. I. Pigment Green 36 (C.I. No. 74265), Pigment Green 37 (C.I. No. 74255), Pigment Blue 16 (C.I. No. 74100), C.I. I. Phthalocyanine pigments such as CI Pigment Blue 75 (C.I. No. 74160: 2) or 15 (C.I. No. 74160); I. Pigment blue 56 (C.I. No. 42800), or C.I. I. Triarylcarbonium pigments such as CI Pigment Blue 61 (C.I. No. 42765: 1); I. Pigment violet 23 (C.I. No. 51319) or C.I. I. Dioxazine pigments such as CI Pigment Violet 37 (C.I. No. 51345); I. Aminoanthraquinone pigments such as CI Pigment Red 177 (C.I. No. 65300); I. Pigment red 254 (C.I. No. 56110), C.I. I. Pigment Red 255 (C.I. No. 561050), C.I. I. Pigment red 264, C.I. I. Pigment red 272 (C.I. No. 561150), C.I. I. Pigment orange 71, or C.I. I. Diketopyrrolopyrrole pigments such as C.I. Pigment Orange 73; I. Thioindigo pigments such as CI Pigment Red 88 (C.I. No. 7313); I. Pigment yellow 139 (C.I. No. 56298), C.I. I. Pigment Orange 66 (C.I. No. 48210) and the like, isoindoline pigments such as C.I. I. Pigment yellow 109 (C.I. No. 56284), or C.I. I. Pigment Orange 61 (C.I. No. 11295) and other isoindolinone pigments, C.I. I. Pigment Orange 40 (C.I. No. 59700), or C.I. I. Pyranthrone pigments such as CI Pigment Red 216 (C.I. No. 59710), or C.I. I. And isoviolanthrone pigments such as CI Pigment Violet 31 (60010).
Preferred organic pigments are quinacridone, diketopyrrolopyrrole, phthalocyanine, or azo.
In the method for producing organic particles of the present invention, two or more kinds of organic pigments or solid solutions of organic pigments can be used in combination.

  Examples of organic dyes that can be used in the present invention include azo dyes, cyanine dyes, merocyanine dyes, and coumarin dyes. Examples of the polymer compound that can be used in the present invention include polydiacetylene and polyimide.

Next, a method for depositing and forming organic particles will be described.
The solvent used for forming the organic particles by precipitation is a poor solvent for the organic material, and is not particularly limited as long as it is compatible with or uniformly mixed with a good solvent for dissolving the organic material. As a poor solvent for the organic material, the solubility of the organic material is preferably 0.02% by mass or less, and more preferably 0.01% by mass or less. This solubility may be the solubility when dissolved in the presence of an acid or alkali. In addition, the compatibility or uniform mixing property between the good solvent and the poor solvent is preferably such that the solubility of the good solvent in the poor solvent is 30% by mass or more, and more preferably 50% by mass or more.
Examples of the poor solvent include aqueous solvents (for example, water, hydrochloric acid, aqueous sodium hydroxide), alcohol solvents, ketone solvents, ether solvents, aromatic solvents, carbon disulfide, aliphatic solvents, nitriles. Examples thereof include a system solvent, a halogen solvent, an ester solvent, an ionic liquid, and a mixed solvent thereof, and an aqueous solvent or an alcohol solvent is preferable.
Examples of the alcohol solvent include methanol, ethanol, isopropyl alcohol, n-propyl alcohol, 1-methoxy-2-propanol and the like. Examples of the ketone solvent include methyl ethyl ketone and methyl isobutyl ketone. Examples of the ether solvent include dimethyl ether, diethyl ether, tetrahydrofuran and the like. Examples of the aromatic solvent include benzene and toluene. Examples of the aliphatic solvent include hexane. Examples of the nitrile solvent include acetonitrile. Examples of the halogen solvent include dichloromethane, trichloroethylene, and the like. Examples of the ester solvent include ethyl acetate, ethyl lactate, 2- (1-methoxy) propyl acetate and the like. The ionic liquids, for example, 1-butyl-3-methylimidazolium and PF ₆ ^-, etc. and salts thereof.

Next, a good solvent that dissolves the organic material will be described.
The good solvent is not particularly limited as long as it can dissolve the organic material to be used and is compatible with or uniformly mixed with the poor solvent used in the preparation of the organic particles. The solubility of the organic material in a good solvent is such that the solubility of the organic material is preferably 0.2% by mass or more, and more preferably 0.5% by mass or more. This solubility may be the solubility when dissolved in the presence of an acid or alkali. The preferred range of the compatibility or uniform mixing property between the poor solvent and the good solvent is as described above.
Examples of good solvents include aqueous solvents (eg, water, hydrochloric acid, aqueous sodium hydroxide), alcohol solvents, amide solvents, ketone solvents, ether solvents, aromatic solvents, carbon disulfide, and aliphatic solvents. Solvents, nitrile solvents, sulfoxide solvents, halogen solvents, ester solvents, ionic liquids, mixed solvents thereof, and the like, aqueous solvents, alcohol solvents, ester solvents, sulfoxide solvents or amide solvents. Are preferred, aqueous solvents, sulfoxide solvents or amide solvents are more preferred, and sulfoxide solvents or amide solvents are particularly preferred.

  Examples of the sulfoxide solvent include dimethyl sulfoxide, diethyl sulfoxide, hexamethylene sulfoxide, sulfolane and the like. Examples of amide solvents include N, N-dimethylformamide, 1-methyl-2-pyrrolidone, 2-pyrrolidinone and 1,3-dimethyl-2-imidazolidinone, 2-pyrrolidinone, ε-caprolactam, formamide, N -Methylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, N-methylpropanamide, hexamethylphosphoric triamide and the like.

Further, the concentration of the organic material solution obtained by dissolving the organic material in the good solvent is desirably a saturated concentration of the organic material with respect to the good solvent in the dissolving condition or a range of about 1/100 of this.
The conditions for preparing the organic material solution are not particularly limited, and a range from normal pressure to subcritical and supercritical conditions can be selected. The temperature at normal pressure is preferably −10 to 150 ° C., more preferably −5 to 130 ° C., and particularly preferably 0 to 100 ° C.

In the method for producing organic particles of the present invention, it is preferable that a poor solvent is contained in a container, and the container is filled with the poor solvent. The temperature of the poor solvent during the preparation of the organic particles is preferably 0 to 100 ° C, and more preferably 5 to 80 ° C.
In the method for producing organic particles of the present invention, a pump can be used when the organic material solution is fed into the mixing chamber provided in the container, but this need not be used. The addition rate of the organic material solution when using a pump is preferably 0.1 to 500 ml / min, more preferably 1 to 400 ml / min, and particularly preferably 5 to 300 ml / min. The addition method when a pump is not used includes gravity drop.
The poor solvent is stirred by a stirring means, and the stirring speed is preferably 100 to 10000 rpm, more preferably 150 to 8000 rpm, and particularly preferably 200 to 6000 rpm.
Moreover, in the manufacturing method of the organic particle of this invention, the mixing chamber provided in the container is satisfy | filled with the poor solvent, An organic material solution is supplied there and particle | grains are produced | generated. The organic material solution is preferably supplied continuously, and the supply rate is preferably 0.1 to 500 ml / min, more preferably 1 to 400 ml / min, and particularly preferably 5 to 300 ml / min. If the supply speed is too high, particles having a large particle size may be mixed, and if it is too slow, the particle size distribution may be widened. The supply speed is preferably controlled in combination with the concentration of the organic material solution used, the stirring speed, and the like.
The ratio of the organic material solution to be added and the poor solvent (organic material solution / poor solvent) is preferably 1/50 to 2/3 in volume ratio, more preferably 1/40 to 1/2, and more preferably 1/20 to 3/8. Is particularly preferred.
The concentration of the organic particle liquid after the preparation of the organic particles is not particularly limited, but the particles are preferably in the range of 10 to 40,000 mg, more preferably in the range of 20 to 30000 mg, and particularly preferably 50 with respect to 1000 ml of the dispersion solvent. It is in the range of ˜25000 mg.
The combination of the good solvent and the poor solvent can be appropriately selected and used depending on the organic material to be used.

  You may use a dispersing agent for the manufacturing method of the organic particle of this invention. For example, an anionic dispersant, a cationic dispersant, an amphoteric dispersant, and a nonionic dispersant can be added. The addition method may be added to the pigment solution, to the poor solvent, or to both. Moreover, you may add, after manufacturing an organic particle.

Regarding particle size, there is a method of expressing the average size of the population by quantifying by the measurement method, but it is often used as the mode diameter indicating the maximum value of the distribution and the median value of the integral distribution curve. There are corresponding median diameters, various average diameters (number average, length average, area average, weight average, volume average, etc.), etc. In the present invention, unless otherwise specified, the particle diameter is the number average diameter. Say.
The particle size of the organic particles (primary particles) contained in the organic particle dispersion produced by the method for producing organic particles of the present invention is 500 μm or less, preferably 100 μm or less, and more preferably 10 μm or less. Further, when producing nanometer-sized nanoparticles, the particle size is preferably 1 nm to 1 μm, more preferably 1 to 200 nm, further preferably 2 to 100 nm, and 5 to 80 nm. It is particularly preferred.

Further, as an index representing the uniformity of particle size (particles are monodispersed and uniform in size), in the present invention, unless otherwise specified, the volume average particle size (Mv) and the number average particle size (Mn ) Ratio (Mv / Mn). Monodispersity of organic particles (primary particles) contained in an organic particle dispersion produced by the method for producing organic particles of the present invention (in the present invention, monodispersity refers to the degree of uniform particle size). That is, Mv / Mn is preferably 1.0 to 2.0, more preferably 1.0 to 1.8, and particularly preferably 1.0 to 1.5.
Examples of the method for measuring the particle size of the organic particles include microscopy, weight method, light scattering method, light blocking method, electrical resistance method, acoustic method, and dynamic light scattering method. The method is particularly preferred. Examples of the microscope used for the microscopy include a scanning electron microscope and a transmission electron microscope. Examples of the particle measuring apparatus by the dynamic light scattering method include Nanotrack UPA-EX150 manufactured by Nikkiso Co., Ltd. and Dynamic Light Scattering Photometer DLS-7000 series manufactured by Otsuka Electronics Co., Ltd.

  In the method for producing organic particles of the present invention, the mixing chamber is stirred by the stirring means, but the poor solvent and the good solvent are rapidly mixed in the mixing chamber by the first stirring means, and the organic particles generated by the second stirring means It is preferable to immediately discharge to the outside of the mixing chamber. About this stirring means and a mixing chamber, the stirring means and mixing chamber which are mentioned later can be used preferably, respectively.

Hereinafter, although the manufacturing apparatus which is a preferable embodiment of this invention is demonstrated based on drawing, this invention is not interpreted limitedly by this.
FIG. 1 is a schematic sectional view of a manufacturing apparatus according to an embodiment of the present invention. In FIG. 1, the organic material solution is preferably continuously supplied into the mixing chamber 3 provided in the liquid tank 1 a in the container 1 through the supply pipe 4. Here, a poor solvent is contained in the container 1, the mixing chamber 3 is provided below the liquid surface 1 b of the poor solvent, and the inside thereof is filled with the poor solvent. The size of the mixing chamber is preferably 1/5 or less in volume ratio with respect to the container, more preferably 1/10 or less, and even more preferably 1/15 or less.
The bulk poor solvent in the reaction vessel 1 is preferably always convected by the action of the mixing chamber 3 so as to cross the mixing chamber 3 from below to above (in the direction of the arrow in FIG. 1). A stirring blade 2 connected to a shaft 5 is provided in the mixing chamber 1 and is rotated by a motor 6. There are no particular limitations on the material forming the container 1, the stirring blade 2, the mixing chamber 3, the supply pipe 4, the shaft 5, and the motor 6, and materials used in ordinary stirring devices can be appropriately selected and used.

  FIG. 2 is an enlarged partial sectional view showing the mixing chamber 3 used in one embodiment of the present invention in a partial cross section. The organic material solution is supplied from the supply pipe 4 into the mixing chamber 3. The size of the opening 4a is preferably 1 cm or less, more preferably 0.8 cm or less, and even more preferably 0.5 cm or less. The position of the opening 4a is preferably lower than the stirring unit of the mixing chamber. Moreover, in order to add in a short time, you may provide the supply pipe | tube 4 and two or more opening parts 4a. In this embodiment, the mixing chamber 3 is formed by a casing 7 made of a rectangular cylinder having a constant cross-sectional area. The upper end of the casing 7 is an open end, and a hole 8 is provided at the lower end. The poor solvent is connected to the bulk poor solvent. The shape of the hole 8 is not particularly limited, and examples thereof include a circle and a rectangle. A plurality of holes may be provided. In this embodiment, the organic material solution supply pipe 4 is provided in a wall constituting the lower end of the casing 7 and opens toward the hole 8. In addition, in the figure, the casing 7 is shown by the longitudinal cross-sectional view in the position in which the supply pipe | tube was provided. A stirring blade 2 is provided in the mixing chamber 3, and the stirring blade is attached to the shaft 5 and rotated by a motor (not shown). By the rotation of 2, the poor solvent is constantly circulated through the circular hole in the mixing chamber 3 from below to above.

The stirring blade 2 provided in the mixing chamber 3 must produce a desired mixing strength in the mixing chamber. This mixing strength is presumed to be an important operating factor for the size of the droplet when the organic material solution is mixed.
In addition, the stirring blade 2 can be combined with other organic particles so that the organic particles generated in the mixing space stay in the mixing chamber 3 to become larger particles, or the organic material solution supplied to the mixing chamber 3 It is preferable to select one that has the ability to quickly draw out the generated organic particles and quickly discharge them out of the mixing chamber 3 so as not to be exposed to large particles and generate large particles.
As long as the said objective is achieved as the stirring blade 2, what kind of thing may be sufficient, for example, a turbine type, a fan turbine type, etc. may be used.
Moreover, the casing 7 is comprised by the square cylinder in this embodiment as mentioned above. For this reason, the corner of the casing 7 disturbs the flow created in the stirring blade 2, and the mixing effect can be further enhanced without requiring an additional material such as a baffle plate.

FIG. 3 is an enlarged partial sectional view showing the mixing chamber 3 in a partial cross section as another embodiment of the present invention. In this embodiment, there are two stirring blades (mixing stirring blade 9 and discharging stirring blade 10), the first stirring means for quickly mixing the poor solvent and the good solvent, and the generated organic particles immediately outside the mixing chamber. 2 is a schematic cross-section of a mixing chamber having a second stirring means for discharging to the bottom.
By providing two stirring blades in this way, the ability to control the mixing strength and the ability to discharge the generated organic particles to the outside of the mixing chamber can be independently selected. Can be independently set to a desired value and operated.

By concentrating the organic particle liquid produced according to the present invention, it is possible to produce a dispersed organic particle liquid suitable for a color filter coating liquid and an inkjet ink on an industrial scale.
Below, the method to concentrate an organic particle liquid is demonstrated. The concentration method is not particularly limited as long as the organic particle liquid can be concentrated. For example, an extraction solvent is added to and mixed with the organic particle liquid, the organic particles are concentrated and extracted into the extraction solvent phase, and the concentrated extract is filtered. A method of filtering to obtain a concentrated particle solution, a method of concentrating organic particles by centrifugation, a method of drying and concentrating a solvent by heating or decompression, or a combination thereof is preferably used. The concentration of the organic particles after concentration is preferably 1 to 100% by mass, more preferably 5 to 100% by mass, and particularly preferably 10 to 100% by mass.

  Hereinafter, a method of concentration extraction will be described. The extraction solvent used for the concentration extraction is not particularly limited, but is not substantially mixed with the dispersion solvent (for example, an aqueous solvent) of the organic particle dispersion (in the present invention, it is not compatible) Is preferably 50% by mass or less, more preferably 30% by mass or less), and a solvent that forms an interface when allowed to stand after mixing. In addition, the extraction solvent is preferably a solvent that generates weak agglomeration in which organic particles can be redispersed in the extraction solvent (redispersion is possible without applying high shearing force such as milling or high-speed stirring). . In such a state, it does not cause strong aggregation that changes the particle size, and the target organic particles are wetted with the extraction solvent, while the dispersion solvent such as water can be easily removed by filter filtration or the like. Is preferable. The extraction solvent is preferably an ester solvent, an alcohol solvent, an aromatic solvent or an aliphatic solvent, more preferably an ester solvent, an aromatic solvent or an aliphatic solvent, and particularly preferably an ester solvent. Examples of the ester solvent include 2- (1-methoxy) propyl acetate, ethyl acetate, and ethyl lactate. Examples of the alcohol solvent include n-butanol and isobutanol. Examples of the aromatic solvent include benzene, toluene, xylene and the like. Examples of the aliphatic solvent include n-hexane and cyclohexane. Further, the extraction solvent may be a pure solvent composed of the above preferred solvents or a mixed solvent composed of a plurality of solvents.

The amount of the extraction solvent is not particularly limited as long as the organic particles can be extracted, but is preferably smaller than the organic particle liquid in consideration of concentration and extraction. When this is shown by volume ratio, when the organic particle liquid is 100, the added extraction solvent is preferably in the range of 1-100, more preferably in the range of 10-90, and in the range of 20-80. Is particularly preferred. If it is too much, it will take a lot of time for concentration, and if it is too little, extraction will be insufficient and particles will remain in the dispersion solvent.
After adding an extraction solvent, it is preferable to stir and mix so that it may fully contact with an organic particle liquid. Conventional methods can be used for stirring and mixing. Although there is no restriction | limiting in particular in the temperature when adding and mixing an extraction solvent, It is preferable that it is 1-100 degreeC, and it is more preferable that it is 5-60 degreeC. Any device may be used for adding and mixing the extraction solvent as long as each step can be preferably performed. For example, a separation funnel type device can be used.

  In order to separate the organic solvent dispersion solvent and the concentrated extract, it is preferable to filter. As the filter filtration apparatus, for example, an apparatus such as pressure filtration can be used. Preferred filters include nanofilters and ultrafilters. It is preferable to remove the remaining dispersion solvent by filter filtration and further concentrate the organic particles in the concentrated extract to obtain a concentrated particle solution.

  According to this concentration method (concentration extraction and filter filtration), organic particles can be efficiently concentrated from the organic particle liquid. Regarding the concentration ratio, for example, the concentration in the organic particle liquid can be preferably concentrated to about 100 to 1000 times, more preferably about 500 to 1000 times. Furthermore, almost no organic particles remain in the dispersion solvent left after extraction of the organic particles, and a high extraction rate can be achieved.

The centrifugation will be described below. Any device may be used as the centrifuge used for concentration of the organic particles by centrifugation as long as the organic particles in the organic particle liquid (or concentrated organic particle liquid) can be precipitated. As a centrifuge, for example, in addition to a general-purpose device, a device with a skimming function (a function of sucking the supernatant layer during rotation and discharging it out of the system) or continuous centrifugation for continuously discharging solid matter Machine.
Centrifugation conditions are preferably 50 to 10000, more preferably 100 to 8000, and particularly preferably 150 to 6000 in terms of centrifugal force (a value representing how many times the gravitational acceleration is applied). Although the temperature at the time of centrifugation is based on the solvent seed | species of a dispersion liquid, -10-80 degreeC is preferable, -5-70 degreeC is more preferable, 0-60 degreeC is especially preferable.

The drying will be described below. The apparatus used for concentration of organic particles by drying under reduced pressure is not particularly limited as long as the solvent of the organic particle liquid (or concentrated organic particle liquid) can be evaporated. For example, a general-purpose vacuum dryer and a rotary pump, an apparatus that can be heated and reduced in pressure while stirring the liquid, and an apparatus that can be continuously dried by passing the liquid through a heated and reduced pressure tube.
The heating and drying temperature is preferably 30 to 230 ° C, more preferably 35 to 200 ° C, and particularly preferably 40 to 180 ° C. The pressure during decompression is preferably 100 to 100,000 Pa, more preferably 300 to 90,000 Pa, and particularly preferably 500 to 80,000 Pa.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited thereto.

Example 1
A pigment solution was prepared by dissolving 15 mmol / L of the pigment (Pigment Red 254) in a solution prepared by mixing 1-methyl-2-pyrrolidone and 1 mol / L-sodium hydroxide aqueous solution at 6: 1. Separately from this, water was prepared as a poor solvent.
In a bottom hemispherical cylindrical reaction vessel having a diameter of 250 mm and a depth of 320 mm, 3000 ml of poor solvent water was placed, and a mixer (length 60 mm × width 60 mm × height 30 mm) as shown in FIG. Was placed at a position 35 mm from the bottom of the reaction vessel, the temperature was controlled at 1 ° C., 15 ° C., 25 ° C., and 35 ° C., and 300 ml of the pigment solution was added to the poor solvent stirred at 1000 rpm at a flow rate of 50 ml / min. The mixture was added to a mixer to prepare an organic pigment particle dispersion. The dispersions obtained at the respective temperatures were used as sample pigment liquids (1) to (4).

(Example 2)
A pigment solution was prepared by dissolving 150 mmol / L of the pigment (Pigment Red 254) in a solution obtained by mixing dimethyl sulfoxide and 8 mol / L-potassium hydroxide aqueous solution at a ratio of 6: 1. Separately from this, water was prepared as a poor solvent.
In a cylindrical reaction vessel having the same mixer as in Example 1, 3000 ml of poor solvent water was added, the temperature was controlled at 1 ° C., 15 ° C., 25 ° C., 35 ° C., and the poor solvent stirred at 1000 rpm 300 ml of the pigment solution was added to the mixer at a flow rate of 50 ml / min to prepare an organic pigment particle dispersion. Dispersions obtained at the respective temperatures were used as sample pigment liquids (5) to (8).

(Comparative Example 1)
A pigment solution prepared in the same manner as in Example 1 and water as a poor solvent were prepared.
Organic pigment particles were prepared by injecting 1 ml of the pigment solution into 10 ml of poor solvent stirred at 1000 rpm with a stir bar in a beaker for 1 second while controlling the temperature at 1 ° C., 15 ° C., 25 ° C., and 35 ° C. A dispersion was prepared. Dispersions obtained at the respective temperatures were used as sample pigment liquids (9) to (12).

(Comparative Example 2)
A pigment solution prepared in the same manner as in Example 1 and water as a poor solvent were prepared.
The pigment solution was added to 3000 ml of poor solvent water controlled at 1 ° C., 15 ° C., 25 ° C., and 35 ° C. and stirred at 1000 rpm with a GK-0222-10 type Lamond Stirrer manufactured by Fujisawa Pharmaceutical Co., Ltd. in a beaker. An organic pigment particle dispersion was prepared by injecting 300 ml at a flow rate of 50 ml / min using an NP-KX-500 large-capacity non-pulsating pump manufactured by Nippon Seimitsu Chemical. Dispersions obtained at the respective temperatures were used as sample pigment liquids (13) to (16).

(Test example)
The particle sizes of the sample pigment liquids (1) to (16) were measured using Nanotrack UPA-EX150 manufactured by Nikkiso Co., Ltd., and the particle size and monodispersity were evaluated. The particle size was evaluated by the number average particle size Mn. The monodispersity was evaluated by a value (Mv / Mn) obtained by dividing the volume average particle diameter Mv by Mn. The results are shown in Table 1.

  The sample pigment solutions (1) to (16) were centrifuged at HIMAC SCR20B manufactured by Hitachi Koki Co., Ltd. at 3500 rpm (2000 times the acceleration of gravity) for 1 hour, and the supernatant was removed. The organic pigment particle concentrated paste that was discarded and settled was collected. After adding water to the obtained paste and adjusting the pigment content to 15%, it was redispersed with an ultrasonic cleaner W-103T manufactured by HONDA, and granulated using Nanotrac UPA-EX150 manufactured by Nikkiso Co., Ltd. The diameter was measured. The pigment content was measured using an Agilent 8453 type spectrophotometer. The results are shown in Table 1.

Details of the reagents used are as follows.
Reagent Manufacturer ----------------------------------
Pigment Red 254 (Irgafore Red) Ciba Specialty Chemicals 1-methyl-2-pyrrolidone Wako Pure Chemical Industries dimethyl sulfoxide Wako Pure Chemical 1 mol / L Sodium hydroxide aqueous solution Wako Pure Chemicals 8 mol / L Water Potassium oxide aqueous solution Wako Pure Chemical Industries, Ltd. -------------------------------------

  From the above results, it was found that according to the method and apparatus for producing organic particles of the present invention, organic particles can be produced stably in a wide temperature range of 1 ° C to 35 ° C. Regarding the conventional reprecipitation method, in which a sample dissolved in a good solvent is injected into a poor solvent with controlled stirring conditions and temperature, organic particles can be produced at room temperature, but the temperature dependence of the particle size is large. was there. In particular, for stable production of organic pigment particles, it is necessary to sufficiently cool the poor solvent, and for industrial mass production, a cooling plant is required, resulting in a significant increase in cost. According to the method and apparatus for producing organic particles of the present invention, the organic particles can be stably produced in a wide temperature range of 1 ° C. to 35 ° C., and a cooling plant is unnecessary, so that it is very suitable for mass production of organic particles. all right. In addition, it is possible to concentrate without changing the particle size and monodispersity, and it is possible to produce organic particle dispersions suitable for color filter coating liquids and inkjet inks on an industrial scale. I understood.

It is sectional drawing which shows schematically the preferable embodiment of the manufacturing apparatus of this invention. FIG. 5 is an enlarged partial cross-sectional view schematically showing a mixing chamber partially in cross section as another preferred embodiment of the production apparatus of the present invention. FIG. 5 is an enlarged partial cross-sectional view schematically showing a mixing chamber in a partial cross section as another preferred embodiment of the production apparatus of the present invention.

Explanation of symbols

1 container 1a liquid tank (solvent)
1b Liquid level 2 Stirring blade 3 Mixing chamber 4 Supply pipe 4a Supply pipe opening 5 Shaft 6 Motor 7 Casing (mixing chamber wall)
8 holes (circular holes)
9,10 stirring blade

Claims (9)

  A method for producing organic particles, in which a solution of an organic material dissolved in a good solvent and a poor solvent of the organic material compatible with the good solvent are mixed to form the organic material as particles, wherein the poor solvent is An organic material dissolved in the good solvent is supplied into a mixing chamber filled in the poor solvent, and is stirred by a stirring means provided in the mixing chamber. A method for producing organic particles, which is characterized.   The stirrer has a first stirrer and a second stirrer, the first stirrer rapidly mixes the poor solvent and the organic material solution in the mixing chamber, and the organic matter generated by the second stirrer The method for producing organic particles according to claim 1, wherein the particles are immediately discharged out of the mixing chamber.   The organic solvent according to claim 1 or 2, wherein the poor solvent of the organic material is an aqueous solvent, an alcohol solvent, a ketone solvent, an ether solvent, an ester solvent, or a mixed solvent thereof. Production method.   The good solvent of the organic material is an aqueous solvent, an alcohol solvent, a ketone solvent, an ether solvent, a sulfoxide solvent, an ester solvent, an amide solvent, or a mixed solvent thereof. The manufacturing method of the organic particle of any one of -3.   The said organic material is an organic pigment, The manufacturing method of the organic particle of any one of Claims 1-4 characterized by the above-mentioned.   The method for producing organic particles according to claim 1, wherein the number average particle diameter of the organic particles is 1 μm or less.   A device for producing organic particles in which a solution of an organic material dissolved in a good solvent and a poor solvent of the organic material compatible with the good solvent are mixed to form the organic material as particles. A container capable of being stored, a mixing chamber provided in the container and filled with the poor solvent therein, and a solution of the organic material provided in the mixing chamber and supplied into the mixing chamber And an organic particle production apparatus comprising a stirring means for mixing and stirring the poor solvent.   The first stirring means for quickly mixing the poor solvent and the good solvent inside the mixing chamber, and the second stirring means for discharging the generated organic particles to the outside of the mixing chamber immediately. 8. The apparatus for producing organic particles according to 7. The number average particle diameter of the said organic particle is 1 micrometer or less, The manufacturing apparatus of the organic particle of Claim 7 or 8 characterized by the above-mentioned.

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