JP4896418B2 - Method for producing organic fine particles and dispersion thereof, and organic fine particles obtained thereby and dispersion thereof - Google Patents

Description

  The present invention relates to a novel method for producing organic fine particles. Furthermore, the present invention relates to a method for producing organic fine particles in which organic fine particles are insolubilized and precipitated in a laminar flow process, organic fine particles obtained by the method, and a dispersion containing the same.

  Research on inorganic / semiconductor nanoparticles began in the 1980s, and research on gold / silver nanoparticles with the expectation of the electric field effect due to fluorescent semiconductor nanoparticles for biolabeling and phase surface plasmons has been conducted extensively. However, research on clear nano-sized particles has been delayed in the field of organic and polymer materials. The main reason for this is that high-temperature heating operations (vacuum deposition, melt deposition, etc.) used in the production of inorganic / semiconductor nanoparticles are generally not applicable to thermally unstable organic compounds. This is because it was difficult to synthesize nano-sized organic fine particles.

On the other hand, regarding nanometer-sized ultrafine particle materials constituting an intermediate region between a bulk and a molecular size, the expectation as an electronic material is higher than before. The reason is that these materials exhibit very interesting properties in terms of optical properties and nonlinear optical characteristics due to the size effect.
Thus, research on organic fine particle materials that have been delayed is expected to be promoted.

  In other fields, dyes have been used as coloring materials for inkjet inks. However, there are problems in terms of water resistance and light resistance, and pigments have been used to improve the problem. The image obtained with the pigment ink has a remarkable advantage in that it is excellent in light resistance and water resistance as compared with the image obtained by the dye-based ink. However, it is difficult to uniformly reduce the size to a nanometer size that can penetrate into the voids on the paper surface, and there is a problem of poor adhesion to paper.

Further, regarding the increase in the number of pixels of a digital camera, it is desired to reduce the thickness of a color filter used in a CCD sensor. An organic pigment is used for this color filter. However, since the thickness of the filter greatly depends on the particle diameter of the organic pigment, it is desired to produce stable fine particles at a nanometer size level.
As described above, there is an increasing expectation for an effective production method that enables research and practical application of organic fine particles in various fields.

As a method for producing organic fine particles developed to meet such expectations, there is a method called “reprecipitation method” (see Patent Documents 1 and 2 and Non-Patent Document 1). This method is useful for nano-crystallization of π-conjugated organic / polymeric substances (eg, low molecular weight aromatic compounds such as polydiacetylene, perylene, fullerene, organic sulfur dyes) and organic pigments that are interested in electronic and optical properties. It is a versatile and excellent method in terms of applicability. There are several methods for reprecipitation, in which the organic compound is dissolved in a solvent (good solvent) that well dissolves the organic compound to be microparticulated, and the solution is dissolved in a solvent (poor solvent) that hardly dissolves the organic compound. Injecting with vigorous stirring to reprecipitate and precipitate, dissolving the organic compound in a solvent that is difficult to dissolve under normal conditions in a supercritical state, and then nanocrystallizing it by mixing with a cooling solvent (supercritical Reprecipitation method).
However, any of these methods makes the particles fine while stirring the solution. Therefore, there is a problem that the stirring effect becomes non-uniform at the time of scale-up, and it is extremely difficult to reproduce at a small scale from the viewpoint of particle size distribution, and improvement thereof has been desired.

  In recent years, a technique for performing a chemical reaction using a reaction channel having a minute channel cross-sectional area, so-called “microchemical process technology”, has attracted attention (Non-Patent Document 2). “Micro chemical process technology” is a material production / chemical analysis technology that uses chemical / physical phenomena expressed in a micro flow channel of several μm to several hundred μm wide created on a solid substrate by micro processing technology. is there.

  In micro space, the Reynolds number is small, so it is dominated by laminar flow, and mixing is performed by molecular diffusion through the interface. In the micro space, the specific surface area of the interface is large, and the movement distance of the molecule is small, so that the mixing is performed instantaneously by molecular diffusion through the interface. Therefore, precise high-speed mixing is possible as compared with turbulent mixing using a stirrer on a normal macro scale. Moreover, since the reaction is generally carried out in a flow, the flow rate can also be precisely controlled, and therefore the reaction time can be precisely controlled. Furthermore, since heat transfer is easy, precise temperature control is possible.

JP-A-6-79168 JP 2004-91560 A NANOSCIENCE AND TECHNOLOGY, “Single Organic Nanoparticles”, Chap.2, 14, 29, Spring-Verlag, Berlin (2003). W. Ehrfeld, V. Hessel, H. Loewe, “Microreactor”, 1Ed. (2000), WILEY-VCH.

  An object of the present invention is to provide a method for producing organic fine particles having a small particle size and a uniform particle size distribution. A further object of the present invention is to provide a new method for producing organic fine particles, which solves the problem at the time of scale-up, which is a problem of the conventional reprecipitation method.

The object of the present invention has been achieved by the following means.
(1) Production of organic fine particles characterized in that a solution in which an organic compound is dissolved in a solvent and a precipitation solvent are both introduced into a flow path and circulated as a laminar flow, and the organic compound is insolubilized and precipitated in the laminar flow process. Method.
(2) The method for producing organic fine particles according to (1), wherein the precipitation solvent is different from that of the solution and can be at least partially diffused in the solution.
(3) The method for producing organic fine particles according to (2), wherein the precipitation solvent is a poor solvent for the organic compound.
(4) The method for producing organic fine particles according to (3), wherein either or both of the solution of the organic compound and the poor solvent contain at least one dispersant.
(5) The method for producing organic fine particles according to any one of (1) to (4), wherein the organic compound is an organic dye compound.
( 6 ) The method for producing organic fine particles according to any one of (1) to ( 5 ), wherein a volume mixing ratio of the solution of the organic compound / the precipitation solvent is 0.01 to 100.
( 7 ) The method for producing organic fine particles according to any one of (1) to ( 6 ), wherein the speed of the fluid flowing in the flow path is 0.1 mL to 300 L / hr.
(8) (1) to (7) any manufacturing method of organic fine particle dispersion you and obtaining the organic fine particles according as the dispersion on one of.
( 9 ) The organic compound solution introduced into the flow path and the deposition solvent come into contact with each other at a fluid confluence to form a laminar flow and flow through the reaction flow path ahead of the fluid confluence (8). The manufacturing method of the organic fine particle dispersion of description.

According to the production method of the present invention, by forming particles in a laminar flow process, it is possible to efficiently produce organic fine particles having a uniform particle size distribution and a sharp particle size distribution. In addition, according to the production method of the present invention, organic fine particles can be produced by precisely controlling the reaction time and reaction temperature by a flow reaction using a laminar flow. can do. Furthermore, by numbering up (paralleling of devices), organic fine particles can be produced with good reproducibility, and the time required for commercialization can be drastically reduced.
In addition, since the organic fine particles obtained by the production method of the present invention and the dispersion thereof can realize a more precise monodispersed state, it can be expected that a new function is expressed in the dispersion or the contained fine particles.

By performing reprecipitation using interfacial molecular diffusion mixing in a flow path (preferably a micrometer size) that forms a laminar flow, the inventors have compared the particle size as compared to the method performed in a conventional flask. It has been found that organic pigment fine particles and dispersions thereof can be obtained. Furthermore, we have found that mass production with high reproducibility can be achieved by using a numbering-up technique, which is a scale-up technique of microchemical process technology.
That is, the present invention is a method for producing organic fine particles in which fine particles are precipitated in a laminar flow process from a solution of an organic compound dissolved in a solvent.

Hereinafter, the production method of the present invention will be described in detail.
The apparatus used in the production method of the present invention is an apparatus having a flow path (channel) having an equivalent diameter of 10 mm or less, and preferably an apparatus having a flow path having an equivalent diameter of 1 mm or less. First, the equivalent diameter will be described below.
Equivalent diameter, also called equivalent diameter, is a term used in the field of mechanical engineering. When an equivalent circular pipe is assumed for a pipe having an arbitrary cross-sectional shape (a flow path in the manufacturing method of the present invention), the diameter of the equivalent circular pipe is referred to as an equivalent diameter. The equivalent diameter (d _eq ) is defined as d _eq = 4 A / p, using A: the cross-sectional area of the pipe, and p: the wet wetting length (circumferential length) of the pipe. When applied to a circular tube, this equivalent diameter corresponds to the circular tube diameter. The equivalent diameter is used to estimate the flow or heat transfer characteristics of the pipe based on the data of the equivalent circular pipe, and represents the spatial scale (typical length) of the phenomenon. The equivalent diameter is as follows: d _eq = 4a ² / 4a = a for a regular square tube with one side a, and the following equation for a regular triangle tube with one side a.

さらに、流路高さｈの平行平板間の流れではｄ_ｅｑ＝２ｈとなる（例えば、（社）日本機械学会編「機械工学事典」１９９７年、丸善（株）参照）。

Furthermore, in the flow between parallel flat plates having a flow path height h, d _eq = 2h (for example, see “Mechanical Engineering Encyclopedia” edited by Japan Society of Mechanical Engineers, 1997, Maruzen Co., Ltd.).

When water is poured into the tube, and a colored tube is injected by inserting a thin tube into the central axis of the tube, the colored solution flows as a single line while the flow rate of water is slow, and the water flows parallel to the tube wall. Flows straight into. However, when the flow velocity is increased and reaches a certain flow velocity, the water flow suddenly becomes turbulent, and the colored liquid is mixed with the water flow to become a colored flow. The former flow is called laminar flow, and the latter flow is called turbulent flow.
Whether the flow becomes laminar or turbulent depends on whether the Reynolds number, which is a dimensionless number indicating the flow, is below a certain critical value. That is, the smaller the Reynolds number, the easier it is to form a laminar flow. The Reynolds number Re of the flow in the pipe is expressed by the following equation.
Re = D <υ _x > ρ / μ
D is the equivalent diameter of the tube, <υ _x > is the average cross-sectional velocity, ρ is the density of the fluid, and μ is the viscosity of the fluid. As can be seen from this equation, the smaller the equivalent diameter, the smaller the Reynolds number. Therefore, in the case of an equivalent diameter of μm, a stable laminar flow is easily formed. It can also be seen that the liquid physical properties of density and viscosity also affect the Reynolds number, and the smaller the density and the larger the viscosity, the smaller the Reynolds number and the easier it is to form a laminar flow.
A Reynolds number indicating a critical value is called a critical Reynolds number. The critical Reynolds number is not necessarily constant, but is approximately the next value.
Re <2300 laminar flow
Re> 3000 Turbulence
3000>Re> 2300 Transient state

As the equivalent diameter of the flow path decreases, the surface area per unit volume (specific surface area) increases, but when the flow path becomes the preferred size, the specific surface area increases dramatically and passes through the wall of the flow path. The heat transfer efficiency is very high. Since the heat transfer time (t) in the fluid flowing through the flow path is expressed by t = d _eq ² / α (α: the thermal diffusivity of the liquid), the heat transfer time becomes shorter as the equivalent diameter becomes smaller. That is, when the equivalent diameter becomes 1/10, the heat transfer time becomes 1/100, and the equivalent diameter is microscale.

  In the production method of the present invention, a reaction apparatus having a microscale flow channel (channel) having a preferred size is generally referred to as a “microreactor” and has been greatly developed recently. The microreactor is provided with a plurality of microchannels having an equivalent diameter of several μm to several hundreds of μm when the cross section is converted into a circle, and a mixing space connected to these microchannels. In the reactor, a plurality of solutions are introduced into a mixing space through a plurality of microchannels, thereby mixing the plurality of solutions or causing a chemical reaction together with the mixing.

  Next, the difference between the reaction by the microreactor as described above and the batch method using a tank or the like will be described. In other words, the chemical reaction in the liquid phase generally occurs when molecules meet at the interface of the reaction solution. Therefore, when the reaction is carried out in a micro space (micro channel), the area of the interface becomes relatively large and the reaction takes place. Efficiency increases significantly. In addition, as described above, the diffusion time of the molecule itself is proportional to the square of the distance. This means that as the scale is reduced, the reaction proceeds more easily due to the diffusion of the molecules without active mixing of the reaction solution, and the reaction tends to occur. Also, in the micro space, since the scale is small, the flow is dominated by laminar flow, and the solutions are in a laminar flow state and are diffused and mixed with each other.

The use of microreactors click te has the characteristics described above, as a reaction site compared with the conventional batch method using a tank having a large volume to allow precise control of reaction time and temperature between the solutions . In the case of a batch system, the reaction proceeds at the reaction contact surface at the initial stage of mixing, particularly between solutions with a high reaction rate, and the primary product generated by the reaction between the solutions continues to be reacted in the vessel. As a result, the product may become non-uniform or agglomeration or precipitation may occur in the mixing container. On the other hand, according to the microreactor, the solution continuously circulates with almost no stagnation in the mixing container. Therefore, while the primary product generated by the reaction between the solutions stays in the mixing container, it continues. It is possible to suppress the reaction, and it becomes possible to take out a pure primary product that has been difficult to take out in the past, and it is difficult to cause aggregation and precipitation in the mixing vessel.

  In addition, when a small amount of chemical substances produced by an experimental production facility is manufactured (scaled up) in a large amount by a large-scale production facility, a large-scale batch method is conventionally used. It took a great deal of labor and time to obtain reproducibility at the production facility, but this reproducibility can be achieved by parallelizing production lines using microrear coolers according to the required production volume. The labor and time for obtaining the potential can be greatly reduced.

A method for producing a laminar flow channel used in the production method of the present invention will be described below. When the flow path is 1 mm or more in size, it can be made relatively easily by using a conventional machining technique. However, when the size is 1 mm or less, particularly 500 μm or less, the production becomes extremely difficult. A micro-sized channel (micro channel) is often formed on a solid substrate using a microfabrication technique. The substrate material may be anything as long as it is a stable material that does not easily corrode. For example, metal (for example, stainless steel, hastelloy (Ni—Fe alloy), nickel, aluminum, silver, gold, platinum, tantalum, or titanium), glass, plastic, silicone, Teflon (registered trademark), or ceramics.

  Typical examples of microfabrication techniques for producing microchannels include LIGA (Roentgen-Lithographie Galvanik Abforming) technology using X-ray lithography, high aspect ratio photo using EPON SU-8 (trade name). Lithography method, micro electric discharge machining method (μ-EDM (Micro Electro Discharge Machining)), deep RIE (Reactive Ion Etching) silicon high aspect ratio processing method, Hot Emboss processing method, optical modeling method, laser processing method, ion beam Machining methods, and mechanical micro-cutting methods using micro tools made of hard materials such as diamond. These techniques may be used alone or in combination. Preferred microfabrication techniques are LIGA technology using X-ray lithography, high aspect ratio photolithography using EPON SU-8, micro electrical discharge machining (μ-EDM), and mechanical micromachining. In recent years, the application of fine injection molding technology to engineering plastics has been studied.

  Joining techniques are often used when creating microchannels. The usual bonding techniques are roughly divided into solid phase bonding and liquid phase bonding, and the commonly used bonding methods are pressure bonding and diffusion bonding as solid phase bonding, welding, eutectic bonding, soldering as liquid phase bonding, Adhesion or the like is a typical joining method. In addition, during assembly, a highly precise bonding method that maintains dimensional accuracy without deteriorating material due to high temperature heating or destruction of micro structures such as flow paths due to large deformation is desirable. There are bonding, anodic bonding, surface activation bonding, direct bonding using hydrogen bonding, bonding using HF aqueous solution, Au-Si eutectic bonding, void-free bonding, and the like.

  The equivalent diameter of the flow path in the apparatus used in the production method of the present invention is 10 mm or less, preferably 1 mm or less. More preferably, it is 10 micrometers-1 mm, Most preferably, it is 20-300 micrometers. The length of the channel is not particularly limited, but is preferably 1 mm or more and 10 m or less, more preferably 5 mm or more and 10 m or less, and particularly preferably 10 mm or more and 5 m or less.

In the production method of the present invention, the organic fine particle dispersion is prepared while flowing in the flow path, that is, by a continuous flow method.
The number of flow paths used in the production method of the present invention can be appropriately provided in the reaction apparatus, and of course, it may be one, but if necessary, several flow paths are arranged in parallel (numbering up). The processing amount can be increased. The number in parallel depends on the type of fine particles to be produced, the target production amount, etc., but is preferably 5 to 1000, more preferably 10 to 100.
The flow paths used in the production method of the present invention are not limited to those created on a solid substrate using a microfabrication technique. For example, various fused silica capillaries having an inner diameter of several μm to several hundred μm that can be obtained. A tube may be used. Various silicon tubes, fluororesin tubes, stainless steel tubes, PEEK tubes (polyether ether ketone tubes) with an inner diameter of several μm to several hundreds of μm that are commercially available for high-performance liquid chromatographs and gas chromatographs are also used. Is possible.
So far, microreactors have been reported on devices aimed at improving reaction efficiency. For example, Japanese Patent Application Laid-Open Nos. 2003-210960, 2003-210963, and 2003-210959 relate to micromixers, and the present invention can use these microdevices.

  You may surface-treat the flow path used with the manufacturing method of this invention according to the objective. In particular, when an aqueous solution is manipulated, surface treatment is important because adsorption of the sample to glass or silicon may be a problem. For fluid control in micro-sized channels, it is desirable to achieve this without incorporating moving parts that require complex manufacturing processes. For example, it is possible to create a hydrophilic region and a hydrophobic region by surface treatment in the flow path, and manipulate the fluid by utilizing the difference in surface tension acting on the boundary. As a method for surface treatment of glass or silicon, hydrophobic or hydrophilic surface treatment using a silane coupling agent is frequently used.

  In order to introduce and mix reagents and samples into the flow path, a fluid control function is required. In particular, since the behavior of the fluid in the microchannel has a property different from that of the macroscale, a control method suitable for the microscale must be considered. The fluid control method includes a continuous flow method and a liquid droplet (liquid plug) method when classified into forms, and an electric drive method and a pressure drive method when classified as a driving force.

  These methods are described in detail below. The most widely used form for handling fluid is the continuous flow system. In continuous flow type fluid control, the entire microchannel is generally filled with fluid, and the entire fluid is generally driven by a pressure source such as a syringe pump prepared outside. This method has a great advantage that a control system can be realized with a relatively simple setup, although it is difficult to have a large dead volume.

  As a method different from the continuous flow method, there is a droplet (liquid plug) method. In this system, droplets partitioned by air are moved in the reactor or in a flow path leading to the reactor, and each droplet is driven by air pressure. At that time, a vent structure that allows the air between the droplet and the channel wall or between the droplets to escape to the outside as needed, and a valve structure that keeps the pressure in the branched channel independent of other parts Etc. need to be prepared inside the reactor system. Further, in order to control the pressure difference and operate the droplet, it is necessary to construct a pressure control system including a pressure source and a switching valve outside. In this way, the droplet system makes the device configuration and the reactor structure somewhat complicated, but it can be operated in multiple stages, such as operating several droplets individually and sequentially performing several reactions. The degree of freedom of configuration increases.

As a drive method for fluid control, an electric drive method in which an electroosmotic flow is generated by applying a high voltage to both ends of a flow channel (channel) and fluid is moved by this, and a pressure source is prepared outside to prepare a fluid. In general, a pressure driving method of moving by applying pressure is widely used. The difference between the two is that, for example, the behavior of the fluid is a flat distribution when the flow velocity profile is electrically driven in the cross section of the flow path, whereas the center of the flow path is It is known that the wall surface is fast and has a slow distribution, and the electric drive method is more suitable for the purpose of moving the sample plug or the like while maintaining its shape. When performing the electrical driving system, since it is necessary that the inside of the flow passage is filled with fluid, but must be adopted in the form of a continuous flow system, it is to perform the fluids by electrical control Therefore, for example, a relatively complicated process of creating a temporal concentration gradient by changing the mixing ratio of two kinds of solutions continuously is realized. In the case of the pressure drive system, there is almost no influence on the substrate because control is possible regardless of the electrical properties of the fluid, and secondary effects such as heat generation and electrolysis do not need to be considered. The application range is wide. On the other hand, it is necessary to automate complicated processes such as the necessity of preparing a pressure source outside and the change of the response characteristics of the operation according to the size of the dead volume of the pressure system.
The method used as the fluid control method in the production method of the present invention is appropriately selected according to the purpose, but is preferably a continuous flow type pressure driving method.

  The temperature control in the flow path used in the production method of the present invention may be controlled by placing the entire apparatus having the flow path in a temperature-controlled container, or a heater structure such as a metal resistance wire or polysilicon. In the apparatus, the thermal cycle may be performed by using this for heating and by natural cooling for cooling. For temperature sensing, when using a metal resistance wire, it is preferable to create another resistance wire that is the same as the heater, and to detect the temperature based on the change in the resistance value. When using polysilicon, Detection is preferably performed using a thermocouple. Moreover, you may heat and cool from the outside by making a Peltier device contact a flow path. Which method is used is selected in accordance with the application and the material of the flow path body.

Examples of preferred reactors used in the production method of the present invention are schematically shown in FIGS. Needless to say, the present invention is not limited to these examples.
1-1 is explanatory drawing of the reactor (10) which has a Y-shaped channel, FIG. 1-2 is sectional drawing of the II line | wire. The shape of the cross section perpendicular to the length direction of the flow path varies depending on the microfabrication technique used, but is a trapezoidal shape or a shape close to a rectangle. When the channel width / depth (especially C, H) is made in a micro size, the solution injected from the introduction ports 11 and 12 by a pump or the like passes through the introduction channel 13a or 13b to the fluid confluence. It contacts at 13d, forms a stable laminar flow, and flows through the reaction channel 13c. During the laminar flow, the solutes contained in the laminar flows are mixed or reacted by molecular diffusion at the interface between the laminar flows. In some cases, a solute that is very slowly diffusing does not cause diffusive mixing between laminar flows and mixes only after reaching the outlet 14. When the two solutions to be injected are easily mixed in the flask, if the flow path length F is long, the flow of liquid can be uniform at the outlet, but when the flow path length F is short, Laminar flow is maintained up to the outlet. When the two solutions to be injected do not mix in the flask and are separated into layers, the two solutions naturally flow as laminar flows and reach the outlet 14.

FIG. 2-1 is an explanatory view of a reaction apparatus (20) having a cylindrical tube-type flow path provided with a flow path inserted on one side, and FIG. 2-2 is a cross-sectional view of the apparatus taken along line IIa-IIa. FIG. 2-3 is a sectional view taken along line IIb-IIb of the apparatus. The shape of the cross section perpendicular to the length direction of the flow path is a circle or a shape close thereto. When the diameter (D, E) of the cylindrical tube is a micro size, the solution injected by a pump or the like from the introduction port 21 and the introduction port 22 contacts at the fluid confluence 23d through the introduction channel 23a and the introduction channel 23b. Then, a stable cylindrical laminar flow is formed and flows through the reaction channel 23c. In the same way as the apparatus of FIG. 1-1, the solutes contained in each laminar flow are mixed or reacted by molecular diffusion at the interface between the laminar flows while flowing as a cylindrical laminar flow. Compared with the device shown in FIG. 1-1 above, the present device having a cylindrical channel has a larger contact interface between the two liquids, and further, there is no portion where the contact interface contacts the device wall surface. The feature is that there is no crystal growth from the contact portion with the wall surface, such as when it is generated by reaction, and the possibility of blocking the flow path is low.

FIGS. 3-1 and 4 are modifications of the apparatus of FIGS. 1-1 and 2-1 so that when the two liquid flows reach the outlet in a laminar flow, they can be separated. When these devices are used, reaction and separation can be performed simultaneously. Moreover, it can be avoided that the two liquids are finally mixed and the reaction proceeds too much or the crystal becomes coarse. When a product or a crystal is selectively present in one liquid, the product or the crystal can be obtained at a higher concentration than when the two liquids are mixed. In addition, by connecting several of these devices, there is a merit that it is possible to purify the generated fine particles.

In the production method of the present invention, a solution of an organic compound uniformly dissolved in a solvent is circulated as a laminar flow in the channel. And the solubility of an organic compound is changed in the process, and organic fine particles and the dispersion liquid containing it are manufactured. This will be described in more detail below.

The organic compound used in the production method of the present invention is a compound that is expected to exhibit a size effect when it is made into fine particles, and is not particularly limited, but preferably an organic electronic material (charge transporting agent, nonlinear optical material, etc.) or function. Organic dye compounds (sensitizing dyes, photoelectric conversion dyes, optical recording dyes, image recording dyes, etc.). More preferred are charge transporting agents, optical recording dyes and image recording dyes. Particularly preferred are organic dye compounds such as optical recording dyes and image recording dyes.
In addition, since the fine particles obtained by the production method of the present invention have the same size, the solubility in a solvent is improved, the temperature during dissolution can be lowered, and the time required for dissolution can be shortened. As a result, it is preferable because the organic compound can be prevented from being thermally decomposed in the dissolving step.

  Specific examples of the charge transfer agent used in the production method of the present invention are shown below, but the present invention is not limited thereto.

  Specific examples of the dye for optical recording used in the production method of the present invention are shown below, but the present invention is not limited thereto.

画像記録用色素を具体的に述べれば、好ましくは顔料色素である。顔料色素はマゼンタ顔料、イエロー顔料、またはシアン顔料であることができる。詳しくは、ペリレン、ペリノン、キナクリドン、キナクリドンキノン、アントラキノン、アントアントロン、ベンズイミダゾロン、ジスアゾ縮合、ジスアゾ、アゾ、インダントロン、フタロシアニン、トリアリールカルボニウム、ジオキサジン、アミノアントラキノン、ジケトピロロピロール、チオインジゴ、イソインドリン、イソインドリノン、ピラントロンまたはイソビオラントロン系顔料またはそれらの混合物などのマゼンタ顔料、イエロー顔料、またはシアン顔料である。

Specifically, the dye for image recording is preferably a pigment dye. The pigment dye can be a magenta pigment, a yellow pigment, or a cyan pigment. Specifically, perylene, perinone, quinacridone, quinacridonequinone, anthraquinone, anthanthrone, benzimidazolone, disazo condensation, disazo, azo, indanthrone, phthalocyanine, triarylcarbonium, dioxazine, aminoanthraquinone, diketopyrrolopyrrole, thioindigo, Magenta pigments such as isoindoline, isoindolinone, pyranthrone or isoviolanthrone pigments or mixtures thereof, yellow pigments, or cyan pigments.

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 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), C.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. 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. It is an isoviolanthrone pigment such as CI Pigment Violet 31 (60010).

In the production method of the present invention, the organic compound may be used alone or in combination of two or more. For example, an organic pigment, a solid solution of an organic pigment, an inorganic pigment, or the like may be used in combination. Preferred pigments are quinacridone, diketopyrrolopyrrole, disazo condensation, or phthalocyanine pigments, and particularly preferred are quinacridone, disazo condensation, or phthalocyanine pigments.

The organic compound used in the production method of the present invention must be uniformly dissolved in a solvent (hereinafter also referred to as a good solvent) (in the present invention, “uniformly dissolved” means when observed under visible light) It means that no turbidity is observed, and the solution generally means a solution obtained through a microfilter of 1 μm or less, or a solution containing no matter filtered through a 1 μm filter.)
The solvent to be used varies depending on the organic compound, but the generally used solvent is a polar solvent. Preferably, fluorine-based alcohol (2,2,3,3-tetrafluoro-1-propanol, etc.), amide-based solvent (dimethylformamide, dimethylacetamide, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, etc. ), Sulfoxide solvents (dimethyl sulfoxide, sulfolane, etc.), ether solvents (tetrahydrofuran, etc.), halogen solvents (chloroform, dichloromethane, etc.), or ionic liquids (1-butyl-3-methylimidazolium tetrafluoroborate, etc.) It is. Particularly preferred are amide solvents or sulfoxide solvents. These solvents may be used alone or in combination.
The amount of the solvent used is an amount capable of uniformly dissolving the organic compound, and is not particularly limited, but is preferably 10 to 500 times by weight, and preferably 20 to 100 times by weight with respect to the organic compound. It is.

Next, a solvent that contacts a solution in which an organic compound is dissolved in a laminar flow process and diffuses into the solution through the interface to precipitate the organic compound as fine particles (hereinafter also referred to as a precipitation solvent) will be described.
The kind of the precipitation solvent is determined by the above-mentioned good solvent, the kind of the organic compound, etc., and it is difficult to uniquely determine by itself. However, as a relationship or combination of the precipitation solvent and the good solvent, it is preferable that the good solvent is a solvent having an organic compound solubility of 1 or more and the precipitation solvent is a solvent having an organic compound solubility of 0.1 or less (the solubility is a saturated solution). The concentration of the solute in the medium, which is expressed as the amount of solute (in grams) in 100 g of solution). Further, in the production method of the present invention, it is preferable that the good solvent and the precipitation solvent are at least partially diffusible from each other (in the present invention, at least a part is diffusible means that each solvent is at least 10% by mass. Defined as a homogeneously mixed solvent). That is, in the production method of the present invention, it is preferable to use, as a precipitation solvent, a poor solvent in which 10% by mass or more of the good solvent is uniformly mixed.
Specifically, for example, when the good solvent is an aqueous medium such as an amide solvent or a sulfoxide solvent, water, an alcohol solvent (such as methanol, ethanol, ethylene glycol, propylene glycol, or diethylene glycol), a lower alkyl ether solvent (Ethylene glycol monomethyl (or ethyl) ether, diethylene glycol monomethyl (or ethyl) ether, or triethylene glycol monoethyl (or butyl) ether, etc.), ketone solvents (acetone, methyl ethyl ketone, cycloxanone, etc.) function as precipitation solvents To do.
When the good solvent is not aqueous, for example, when it is a halogen-based solvent, hydrocarbon solvents (such as n-hexane and toluene) and ester solvents (such as ethyl acetate) function as the precipitation solvent, in addition to the above solvents other than water. To do. Preferred are water, alcohol solvents, and hydrocarbon solvents. The good solvent and the precipitation solvent may be used alone or in combination. Moreover, the solution and / or precipitation solvent which melt | dissolved the said organic compound may contain inorganic or organic salt, an acid, an alkali, etc. as needed.
Further, the precipitation solvent is preferably a poor solvent for the organic compound dissolved in the solvent (in the present invention, the poor solvent is a solvent having a low solubility with respect to the solute (the organic compound in the present invention), for example, the solubility is 0. .1 or less solvent).

The mixing ratio of a good solvent (or a solution of an organic compound) and a precipitation solvent depends on the type of organic compound to be microparticulated, and varies depending on the size of the microparticle to be manufactured. Generally, the precipitation solvent / good solvent (or organic compound solution) is 0.01 to 100, preferably 0.05 to 10. The range of the flow rate ratio when laminar flow is the same.
In the production method of the present invention, it is preferable to introduce a solution in which the organic compound is uniformly dissolved into the flow path. When the suspension is added, the particle size increases or the distribution becomes fine particles. In some cases, the flow path is easily blocked.

In the production method of the present invention, fine particles are produced by changing the solubility in the course of flowing through the flow channel, but the method has a flow channel having an inlet different from the inlet of the homogeneous solution of the organic compound, for example, FIG. -1, or a flow path having at least two inlets as shown in FIG. Specifically, a homogeneous solution of an organic compound is introduced into the introduction port 11 in FIG. 1-1 or the introduction port 21 in FIG. 2-1, and then introduced into the introduction port 12 in FIG. 1-1 or the introduction port 22 in FIG. 2-1. The solubility of the solution containing an organic compound is changed by introducing a poor solvent and bringing both solutions into contact with each other in the flow path 13c or 23c. When the equivalent diameter of the flow path is microscale, a stable laminar flow (cylindrical laminar flow in FIG. 2-1) is formed because the Reynolds number is small. At this time, the solvent in both layers diffuses and moves through a stable interface between the layers. Then, the solubility of the organic compound gradually decreases in the solution layer containing the organic compound. Thereby, the organic compound becomes difficult to dissolve, becomes insoluble and precipitates as fine particles.

  The organic fine particles generated in the micro-scale channel do not diffuse and flow to the outlet while being contained in one laminar flow, so that the flow having the outlet designed as shown in FIG. 3-1 or FIG. When the road device is used, a laminar flow containing organic fine particles can be separated. When this method is used, a concentrated organic fine particle dispersion can be obtained, and at the same time, excess dispersant and the like can be removed, which is advantageous. In addition, by mixing the two liquids finally, it is possible to avoid coarsening of the fine particles and alteration of the pigment crystals.

In the method for producing organic fine particles of the present invention, the reaction temperature in the flow path is not limited as long as the solvent does not coagulate or vaporize at the pressure used, but is preferably −20 to 90 ° C., more preferably Is 0-50 ° C. Especially preferably, it is 5-30 degreeC.
In the method for producing pigment fine particles of the present invention, the velocity (flow rate) of the fluid flowing in the flow path is advantageously 0.1 mL to 300 L / hr, preferably 0.2 mL to 30 L / hr, more preferably 0.5 mL. -15 L / hr, particularly preferably 1.0 mL to 6 L / hr.

  In the method for producing organic fine particles of the present invention, a dispersant can be added in a solution containing an organic compound or / and in a poor solvent for changing the solubility. The dispersant (1) quickly adsorbs on the surface of the deposited organic fine particles to form fine particles, and (2) has an action of preventing these particles from aggregating again. In the production method of the present invention, as such a dispersant, an anionic, cationic, amphoteric, nonionic or pigmentary low molecular or high molecular dispersant can be used. These dispersants can be used alone or in combination.

  Anionic dispersants (anionic surfactants) include N-acyl-N-methyltaurine salts, fatty acid salts, alkyl sulfate esters, alkyl benzene sulfonates, alkyl naphthalene sulfonates, dialkyl sulfosuccinates, alkyl phosphorus Examples include acid ester salts, naphthalene sulfonic acid formalin condensate, polyoxyethylene alkyl sulfate ester salts, and the like. Of these, N-acyl-N-methyl taurate is preferable. These anionic dispersants can be used singly or in combination of two or more.

  Cationic dispersants (cationic surfactants) include quaternary ammonium salts, alkoxylated polyamines, aliphatic amine polyglycol ethers, aliphatic amines, diamines and polyamines derived from aliphatic amines and fatty alcohols, fatty acids And imidazolines derived from these and salts of these cationic substances. These cationic dispersants can be used singly or in combination of two or more.

The amphoteric dispersant is a dispersant having both an anion group part in the molecule of the anionic dispersant and a cationic group part in the molecule of the cationic dispersant.

  Nonionic dispersants (nonionic surfactants) include polyoxyethylene alkyl ether, polyoxyethylene alkyl aryl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene alkylamine, Examples thereof include glycerin fatty acid esters. Of these, polyoxyethylene alkylaryl ether is preferable. These nonionic dispersants can be used singly or in combination of two or more.

  When the organic compound is an organic pigment, a pigment dispersant can be used as the dispersant. The pigment dispersant is defined as a pigment dispersant which is derived from an organic pigment as a parent substance and is produced by chemically modifying the parent structure. For example, sugar-containing pigment dispersants, piperidyl-containing pigment dispersants, naphthalene or perylene-derived pigment dispersants, pigment dispersants having functional groups linked to the pigment parent structure through methylene groups, and polymer-modified pigment parents. Examples include a structure, a pigment dispersant having a sulfonic acid group, a pigment dispersant having a sulfonamide group, a pigment dispersant having an ether group, or a pigment dispersant having a carboxylic acid group, a carboxylic ester group, or a carboxamide group.

  Specifically, as the polymer dispersant, polyvinyl pyrrolidone, polyvinyl alcohol, polyvinyl methyl ether, polyethylene oxide, polyethylene glycol, polypropylene glycol, polyacrylamide, vinyl alcohol-vinyl acetate copolymer, polyvinyl alcohol-partial formalized product, Polyvinyl alcohol-partially butyralized product, vinyl pyrrolidone-vinyl acetate copolymer, polyethylene oxide / propylene oxide block copolymer, polyacrylate, polyvinyl sulfate, poly (4-vinylpyridine) salt, polyamide, polyallylamine salt, Condensed naphthalene sulfonate, styrene-acrylate copolymer, styrene-methacrylate copolymer, acrylate ester-acrylate copolymer, acrylate ester Methacrylate copolymer, methacrylate ester-acrylate copolymer, methacrylate ester-methacrylate copolymer, styrene-itaconate copolymer, itaconate-itaconate copolymer, vinyl Examples thereof include naphthalene-acrylate copolymer, vinyl naphthalene-methacrylate copolymer, vinyl naphthalene-itaconate copolymer, cellulose derivative, starch derivative and the like. In addition, natural polymers such as alginate, gelatin, albumin, casein, gum arabic, tonganto gum and lignin sulfonate can also be used. Of these, polyvinylpyrrolidone is preferable. These polymers can be used alone or in combination of two or more.

  As a preferred embodiment, when the precipitation solvent is water or an alcohol solvent, an anionic dispersant is contained in the precipitation solvent, and a nonionic dispersant and / or a polymer dispersant is contained in the solution in which the organic compound is dissolved. Can be mentioned. Further, in the production method of the present invention, the addition of other compounds to the organic compound solution or the precipitation solvent is not prevented unless the effects of the present invention are impaired.

  The amount of the dispersant is preferably in the range of 0.1 to 250 parts by mass, more preferably 100 parts by mass with respect to 100 parts by mass of the organic compound in order to further improve the uniform dispersibility and storage stability of the organic fine particles. It is the range of 1-100 mass parts.

There is a method for expressing the average size of the population by quantifying in the particle measurement method, but the most commonly used is the mode diameter indicating the maximum value of the distribution and the median diameter corresponding to the median value of the integral distribution curve. , And various average diameters (length average, volume average, area average, weight average, number average, etc.). The particle size of the organic fine particles produced by the production method of the present invention is arbitrary as long as the flow path is not blocked, but the median diameter is preferably 1 μm or less. Particularly preferably, it is 3 nm to 800 nm.

  Polydispersity is an index indicating that the particle sizes of the fine particles are uniform, that is, monodispersity of the fine particles, which is obtained by dividing the volume average diameter (MV) by the number average diameter (MN). If the MV / MN value is close to 1, a very sharp distribution is shown (so-called monodispersion), and if the value is large, a wide distribution is obtained. In the production method of the present invention, the organic fine particles have a value of 1.2 to 2.5, preferably 1.2 to 1.6.

  In the method for producing organic fine particles of the present invention, a flow reaction using a flow path is performed under the conditions for forming a laminar flow, the reaction time is controlled, and the precision of reaction temperature control in a narrow space is utilized. By producing fine particles, it is possible to produce organic fine particles that are smaller in size and uniform than conventional reprecipitation methods. Also, unlike conventional scale-up, they are manufactured with numbering (parallel equipment) with good reproducibility. This makes it possible to drastically reduce the time required for commercialization.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited thereto. The particle size distribution shown in the examples was measured with a Microtrac UPA150 manufactured by Nikkiso Co., Ltd.

Example 1
1.0 g of the charge transfer agent of Exemplified Compound (I-1) is dissolved by heating and stirring in 100 g of tetrahydrofuran and returned to room temperature, and this is passed through a 0.45 μm microfilter (manufactured by Fuji Photo Film Co., Ltd.). An IA solution was prepared by removing impurities. Flow path width A: 100 μm, flow path width B: 100 μm, flow path width C: 200 μm, flow path length F: 12 cm, flow path depth H: Y-shaped as shown in FIG. In a reaction apparatus (glass chip) having a flow path, two Teflon (registered trademark) tubes are connected to the introduction port 11 and the introduction port 12 using connectors, and only syringes containing only IA liquid and methanol are respectively connected thereto. And connected to the pump. A Teflon (registered trademark) tube was also connected to the discharge port 14 using a connector. At room temperature (about 20 ° C.), when the IA solution is sent at a rate of 20 μL / min and methanol is sent at a rate of 200 μL / min, a laminar flow is formed, and the fine particle dispersion of the exemplary compound (I-1) in the channel 13C Was obtained, and was collected from the tip of the tube continuously for 1 hour. When the particle size distribution of the fine particles in the obtained dispersion was measured using a dynamic light scattering particle size measuring apparatus, the median size was 30 nm. The MV / MN value, which is an index of monodispersity, was 1.40.

  Ten glass chips used in the above reaction were arranged, and a manifold capable of diverging into ten pieces was attached to the tip of two syringes, and liquids were fed to the inlets 11 and 12 of each glass chip. At room temperature (about 20 ° C.), when the IA solution is sent at a feed rate of 200 μL / min and methanol is sent at a feed rate of 2000 μL / min, a laminar flow is formed, and the exemplified compound (I-1) Since a fine particle dispersion was obtained, it was continuously collected for one hour from the tip of the tube attached to the ten outlets 14. As a result, the production amount per unit time has increased 10 times. When the particle size distribution of the fine particles in the obtained dispersion was measured using a dynamic light scattering particle size measuring apparatus, the median diameter was 31 nm, and the MV / MN value, which is an index of monodispersity, was 1. .39. Fluctuation in particle size distribution was hardly observed due to the scale-up.

(Comparative Example 1)
1.2 ml of the IA solution prepared in Example 1 was dropped into 12 ml of methanol over 1 hour with vigorous stirring. When the particle size distribution of this was measured using a dynamic light scattering particle size measuring apparatus, the median diameter was 45 nm. The MV / MN value, which is an index of monodispersity, was 1.60.

  The above reaction was then scaled up 10 times. That is, 12 ml of IA solution was dropped into 120 ml of methanol over 1 hour. When the particle size distribution of the obtained dispersion was measured using a dynamic light scattering particle size measuring apparatus, the median diameter was 57 nm, and the MV / MN value, which is an index of monodispersity, was 1.75. It was. The fluctuation of the particle size distribution became larger by scaling up.

(Example 2)
1.0 g of cyanine dye of Exemplified Compound (II-1) was dissolved in 100 g of 2,2,3,3-tetrafluoro-1-propanol at room temperature (IIA solution). Impurities such as dust were removed by passing these through a 0.45 μm microfilter (manufactured by Fuji Photo Film Co., Ltd.). The outlet separation shown in FIG. 3A made of glass having channel widths I, J, L, M: 100 μm, channel width K: 200 μm, channel path length Q: 10 cm, channel depth S: 40 μm In a reaction apparatus (glass chip) having a Y-shaped channel, two Teflon (registered trademark) tubes are connected to the inlet 31 and the inlet 32 using connectors, and only the IIA liquid and ethyl acetate are respectively connected to the tip. The syringe containing was connected and set in the pump. Teflon (registered trademark) tubes were also connected to the discharge ports 34 and 35 using connectors. At room temperature (about 20 ° C.), when the IIA solution is sent at a feed rate of 20 μL / min and ethyl acetate is sent at a feed rate of 200 μL / min, a laminar flow is formed, and the fine particles of the exemplified compound (II-1) are formed in the channel 33C. It was generated in the flow path Q and reached 33e while maintaining the laminar flow, and most of the liquid containing fine particles was discharged from the discharge port 34. This liquid was collected from the tip of the tube continuously for 1 hour. When the particle size distribution of the fine particles in the obtained dispersion was measured using a dynamic light scattering particle size measuring apparatus, the median size was 50 nm. The MV / MN value, which is an index of monodispersity, was 1.30.

  Ten glass chips used in the above reaction were arranged, a manifold capable of diverging into ten pieces was attached to the tip of two syringes, and liquids were fed to the inlets 31 and 32 of each glass chip. At room temperature (about 20 ° C.), when the IIA solution is sent at a feed rate of 200 μL / min and ethyl acetate is sent at a feed rate of 2000 μL / min, a laminar flow is formed, and the exemplified compound (II-1) is formed in the channel 33C of each chip. The fine particle dispersion was obtained and collected from the tip of the tube attached to the ten outlets 14. As a result, the production amount per unit time has increased 10 times. When the particle size distribution of the fine particles in the obtained dispersion was measured using a dynamic light scattering particle size measuring apparatus, the median diameter was 49 nm, and the MV / MN value, which is an index of monodispersity, was 1. .31. Fluctuations in particle size distribution due to scale-up were hardly observed.

(Comparative Example 2)
1.2 ml of the IIA solution prepared in Example 2 was dropped into 12 ml of ethyl acetate over 1 hour with vigorous stirring. When the particle size distribution of this was measured using a dynamic light scattering particle size measuring apparatus, the median diameter was 66 nm. The MV / MN value, which is an index of monodispersity, was 1.40.

  The above reaction was then scaled up 10 times. That is, 12 ml of the IIA solution was dropped into 120 ml of ethyl acetate over 1 hour. When the particle size distribution of the obtained dispersion was measured using a dynamic light scattering particle size measuring apparatus, the median diameter was 75 nm, and the MV / MN value, which is an index of monodispersity, was 1.65. It was. The fluctuation of the particle size distribution became larger by scaling up.

(Example 3)
0.01 g of 2,9-dimethylquinacridone (Pigment Red 122) was dissolved in 10 mL of N-methylpyrrolidone using ultrasonic waves, 0.05 g of the polymer dispersant polyvinylpyrrolidone (K30) was added thereto, and the mixture was mixed at room temperature. . Although this solution was slightly cloudy, it passed through a 0.45 μm microfilter (Fuji Photo Film Co., Ltd.) to obtain a IIIA solution as a uniform solvent. In the reaction apparatus having the cylindrical flow path shown in FIG. 2A having a flow path diameter D of 100 μm, a flow path diameter E of 400 μm, a flow path length G of 20 cm, a portion of the flow path length G can be kept at 25 ° C. A jacket capable of circulating constant temperature water was installed. Then, two Teflon (registered trademark) tubes were connected to the introduction port 21 and the introduction port 22 using connectors. A syringe containing the above-mentioned IIIA solution was connected to the inlet 21 and set in a syringe pump. A syringe containing a 0.1% by weight aqueous solution (IIIB solution) of a surfactant N-oleyl-N-methyltaurine sodium salt was connected to the inlet 22 and set in a syringe pump. A 2,9-dimethylquinacridone fine particle dispersion obtained from the discharge port 24 is formed by laminar flow by feeding at a liquid feed rate of 1.0 ml / h from the inlet 21 and 10.0 ml / h from the inlet 22. Collection continued for 1 hour. When the particle size distribution of the fine particles in the obtained dispersion was measured using a dynamic light scattering particle size measuring apparatus, the median size was 20 nm, and the MV / MN value, which is an index of monodispersity, was 1. .42.

  Ten cylindrical flow path devices used in the above reaction were arranged, a manifold capable of diverging into ten pieces was attached to the tip of two syringes, and liquids were fed to the inlets 21 and 22 of each device. Each flow path length G is maintained at 25 ° C., and a laminar flow is formed by sending the IIIA solution at 10 ml / h and the IIIB solution at 100 ml / h. -The dimethylquinacridone fine particle dispersion was combined and collected for one hour. As a result, the production amount per unit time has increased 10 times. When the particle size distribution of the fine particles in the obtained dispersion was measured using a dynamic light scattering particle size measuring apparatus, the median diameter was 21 nm and the MV / MN value, which is an index of monodispersity, was 1. .41. Fluctuation of particle size distribution due to scale-up was hardly observed

(Comparative Example 3)
1 ml of the IIIA solution prepared in Example 3 was dropped into 10 ml of the IIIB solution over 1 hour with vigorous stirring. When the particle size distribution of this was measured using a dynamic light scattering particle size measuring apparatus, the median size was 25 nm. The MV / MN value, which is an index of monodispersity, was 1.44.

  The above reaction was then scaled up 10 times. That is, 10 ml of the IIIA solution was dropped into 100 ml of the IIIB solution over 1 hour. When the particle size distribution of the obtained dispersion was measured using a dynamic light scattering particle size measuring apparatus, the median diameter was 35 nm, and the MV / MN value, which is an index of monodispersity, was 1.70. It was. The fluctuation of the particle size distribution became larger by scaling up.

It is explanatory drawing of the reaction apparatus which has a Y-shaped channel on one side. It is sectional drawing of the II line | wire of FIGS. 1-1. It is explanatory drawing of the reaction apparatus which has a cylindrical tube type flow path provided with the flow path penetrated to one side. It is sectional drawing of the IIa-IIa line | wire of FIGS. It is sectional drawing of the IIb-IIb line | wire of FIGS. It is explanatory drawing of the reactor which has a Y-shaped channel on both sides. It is sectional drawing of the III-III line of FIGS. It is explanatory drawing of the reaction apparatus which has a cylindrical tube type flow path provided with the flow path penetrated on both sides.

Explanation of symbols

10, 20, 30, 40 Reactor body 11, 12, 21, 22, 31, 32, 41, 42 Inlet 13, 33 Channel 13a, 13b, 23a, 23b, 33a, 33b, 43a, 43b Inlet channel 13c, 23c, 33c, 43c Reaction flow path 13d, 23d, 33d, 43d Fluid confluence 33e, 43e Fluid diversion point 33f, 33g, 43f, 43g Discharge flow path 14, 24, 34, 35, 44, 45 Discharge port

Claims (9)

  A method for producing organic fine particles, wherein a solution obtained by dissolving an organic compound in a solvent and a precipitation solvent are both introduced into a flow path and circulated as a laminar flow, and the organic compound is insolubilized and precipitated in the laminar flow process.   2. The method for producing organic fine particles according to claim 1, wherein the precipitation solvent is different from that of the solution and can be at least partially diffused in the solution.   The method for producing organic fine particles according to claim 2, wherein the precipitation solvent is a poor solvent for the organic compound.   The method for producing organic fine particles according to claim 3, wherein at least one dispersant is contained in one or both of the organic compound solution and the poor solvent.   The method for producing organic fine particles according to claim 1, wherein the organic compound is an organic dye compound. The method for producing organic fine particles according to any one of claims 1 to 5 , wherein a volume mixing ratio of the solution of the organic compound / the precipitation solvent is 0.01 to 100. The method for producing organic fine particles according to any one of claims 1 to 6 , wherein the velocity of the fluid flowing in the flow path is 0.1 mL to 300 L / hr. The method of producing an organic fine particle dispersion of organic fine particles you and obtaining as a dispersion according to any one of claims 1-7. The organic compound solution according to claim 8, wherein the organic compound solution introduced into the flow path and the deposition solvent contact at a fluid confluence to form a laminar flow and flow through the reaction flow path ahead of the fluid confluence. A method for producing a fine particle dispersion.

Images