JP5140337B2 - Functional resin powder manufacturing system and functional resin powder manufacturing method - Google Patents

Description

  The present invention relates to a functional resin powder production system and a functional resin powder production method, and more specifically, a functional resin powder comprising solid particles of a functional resin composition containing, for example, a thermoplastic resin as a medium. The present invention relates to a functional resin powder production system and a functional resin powder production method capable of continuously and efficiently producing a functional resin powder.

  As a technique for producing this kind of powder, there are techniques described in Patent Documents 1 and 2. Patent Document 1 describes a method for producing a spherical composite powder, and Patent Document 2 describes a method for producing a biodegradable spherical composite powder. Since the technology of Patent Literature 1 and the technology of Patent Literature 2 are basically the same except that the spherical composite powder of Patent Literature 1 is further specified as a biodegradable spherical composite powder, Patent Literature 1 Will be described.

  In the technique of Patent Document 1, a thermoplastic composite composition containing a thermoplastic resin and a filler is heated to a temperature equal to or higher than the melting point of the thermoplastic composite composition together with a dispersion medium that is incompatible with the thermoplastic composite composition. Then, after obtaining a mixture in which the thermoplastic composite composition is dispersed in a dispersion medium, the mixture is cooled, and a developing solvent that is a poor solvent for the thermoplastic composite composition and a good solvent for the dispersion medium By mixing, the dispersion medium is dissolved in the developing solvent, and a suspension in which the solid fine particles of the thermoplastic composite composition are dispersed is obtained. The suspension is centrifuged and filtered to obtain the desired composite powder.

JP 2001-114901 A JP 2002-327066 A

  However, in the conventional technology, when recovering the solid fine particles of the thermoplastic composite composition from the suspension, a developing solvent that is a poor solvent for the thermoplastic composite composition and a good solvent for the dispersion medium is used. After the dispersion medium is dissolved in the developing solvent, the solid fine particles of the thermoplastic composite composition are separated from the suspension by centrifugation, filtration, or a combination thereof. In such a conventional method of simple centrifugation, filtration, or a combination thereof, unless a large amount of a developing solvent is used to promote dissolution of the dispersing medium in the developing solvent, the dispersion medium is in a solid state of the thermoplastic composite composition. It is difficult to sufficiently separate and remove from the fine particles, and the dispersion medium has an affinity for the thermoplastic composite composition. Therefore, in order to sufficiently remove the dispersion medium from the solid fine particles, conventional centrifugal separation operations and The filtration operation or a method that simply combines these operations requires repeating these operations many times, which complicates the operation process and makes it impossible to efficiently obtain solid fine particles, which in turn is complex. The production cost of the powder increases. As the composite powder becomes finer, separation becomes more difficult.

The present invention has been made in order to solve the above-described problems. The functional resin powder containing a thermoplastic resin is easily separated from the dispersion medium as solid fine particles, and the functional resin powder containing the thermoplastic resin is provided. The present invention provides a functional resin powder production system and a functional resin powder production method capable of continuously and efficiently producing a body as solid fine particles and capable of significantly reducing production costs. It is aimed.

The functional resin powder production system according to claim 1 of the present invention includes a functional resin composition containing at least a thermoplastic resin and exhibiting a predetermined function, and a dispersion medium incompatible with the functional resin composition. preparative, the functional mixture while heating to a temperature above the melting point of the resin composition, developing solvent a poor solvent is a good solvent for the dispersion medium with respect to the functional resin composition of this mixture was stirred with the mixture was added, the developing solvent is the mixture applied is cooled to a temperature below the melting point of the functional resin composition and the dispersion medium is dissolved in the developing solvent during which the A functional resin powder manufacturing system that separates and recovers the functional resin composition powder from the suspension, and the dispersion medium contains the dispersion medium. Specific gravity and viscosity And small and diluent adding means for adding the diluent to enlarge the difference in specific gravity between the liquid mixture and the functional resin composition after dilution, is diluted by the diluent density and viscosity than the liquid mixture decreases And a powder recovery means for recovering the functional resin composition as a functional resin powder from a diluted mixed liquid in which the specific gravity difference with the functional resin composition increases , and the powder recovery means, It is a centrifuge that centrifuges the functional resin powder from a diluted mixed solution .

  The functional resin powder production system according to claim 2 of the present invention is the invention according to claim 1, wherein a distillation apparatus for recovering the diluted solution is provided on the downstream side of the centrifuge. It is characterized by this.

  The functional resin powder production system according to claim 3 of the present invention is characterized in that, in the invention according to claim 2, the diluting solution adding means and the distillation apparatus are connected. .

The method for producing functional resin powder according to claim 4 of the present invention includes a functional resin composition containing at least a thermoplastic resin and exhibiting a predetermined function, and is incompatible with the functional resin composition. and a dispersion medium, the heating to a temperature above the melting point of the functional resin composition Nagarae mixed, a poor solvent for the functional resin composition to the mixture in a good solvent for the dispersion medium A developing solvent is added and stirred together with the mixture, and the mixture to which the developing solvent is added is cooled to a temperature not higher than the melting point of the functional resin composition, while the dispersion medium is dissolved in the developing solvent. The functional resin composition is made into a suspension, and the functional resin powder is produced by separating and recovering the functional resin composition powder from the suspension. a liquid, a mixture of the above-mentioned dispersion medium and the developing solvent A step of dilution with diluent to enlarge the difference in specific gravity between the specific gravity and viscosity is small and the mixed solution and the functional resin composition after dilution, it it is diluted with the diluent density and viscosity than the liquid mixture And a step of centrifugal sedimentation of the functional resin composition as a functional resin powder from a diluted mixed solution that becomes smaller and has a larger specific gravity difference from the functional resin composition. .

  The method for producing a functional resin powder according to claim 5 of the present invention includes the step of recovering the diluted solution by distilling the separated solution separated by the centrifugal sedimentation in the invention according to claim 4. It is characterized by having.

Further, the method of producing functional resin powder according to claim 6 of the present invention is the invention according to claim 4 or claim 5, using water as the developing solvent, A alcohols such as the above diluent Alternatively, ketones are used.

  Moreover, the manufacturing method of the functional resin powder of Claim 7 of this invention is the functional resin which has an average particle diameter of 10 micrometers or less in the invention of any one of Claims 4-6. The powder is collected.

  The functional resin powder production method according to claim 8 of the present invention is the method according to any one of claims 4 to 7, wherein the functional resin powder is a toner. It is characterized by.

According to the present invention, the functional resin powder containing the thermoplastic resin is easily separated from the dispersion medium as solid fine particles, and the functional resin powder containing the thermoplastic resin is continuously and efficiently used as solid fine particles. Thus, it is possible to provide a functional resin powder production system and a functional resin powder production method that can be manufactured efficiently and that can significantly reduce the production cost.

  Hereinafter, the present invention will be described based on the embodiment shown in FIGS. 1 is a block diagram showing an embodiment of the functional resin powder production system of the present invention, FIG. 2 is a cross-sectional view showing the centrifuge shown in FIG. 1, and FIG. 3 is a diagram showing the filtration device shown in FIG. FIG.

  The functional resin powder production system of the present invention comprises a functional resin composition containing a thermoplastic resin as a medium and a dispersion medium incompatible with the functional resin composition, the melting point of the functional resin composition or higher. The mixture is heated to and mixed with a developing solvent that is a poor solvent for the functional resin composition and a good solvent for the dispersion medium, and a temperature not higher than the melting point of the functional resin composition. The functional resin powder is manufactured by dissolving the dispersion medium in a developing solvent to form a suspension of the functional resin composition, and separating and recovering the functional resin composition powder from the suspension. To do. The functional resin in the present invention corresponds to a composite powder in the prior art, and refers to a thermoplastic resin containing a substance such as an inorganic compound or an organic compound that exhibits a predetermined function, such as toner.

  The thermoplastic resin constituting the functional resin powder has a role of a binder of a substance that exhibits a predetermined function. A substance exhibiting a predetermined function has various physical and chemical properties, and can impart various physical and chemical properties to the functional resin powder using a thermoplastic resin as a medium. The thermoplastic resin is not particularly limited, but is selected from, for example, polyamide (PA), polypropylene (PP), polyethylene (PE), styrene-acrylonitrile copolymer (SAN), polycaprolactone (PCL), and polylactic acid (PLA). A thermoplastic resin containing any one of the above is preferably used.

  The dispersion medium is not particularly limited as long as it is a solvent compatible with the functional resin composition, and can be appropriately selected depending on the functional resin composition. When the thermoplastic resin constituting the functional resin composition is polypropylene or polyethylene, polyalkylene oxides such as polyethylene glycol and polyethylene oxide can be used as the dispersion medium. Further, when the thermoplastic resin is polylactic acid, polyacrylic acid can be used as a dispersion medium.

The developing solvent is not particularly limited as long as it is a poor solvent that hardly dissolves the functional resin composition and is a good solvent compatible with the dispersion medium . For example in the case of using the polyalkylene oxides as dispersion medium, water can be used as developing solvent. When the solid fine particles of the functional resin composition are separated and recovered from the suspension, the solid fine particles are washed with a cleaning liquid. In the case of washing, when water is used as the developing solvent, water can also be used as the washing liquid. However, even if the dispersion medium can be dissolved in the developing solvent, the affinity between the solid fine particles and the dispersion medium is strong, and it is difficult to separate the dispersion medium from the solid fine particles.

  In view of this, the present applicant and a co-applicant proposed in Japanese Patent Application No. 2006-171206 a method for separating a dispersion medium from solid fine particles using a pressure filtration device. However, according to the subsequent examination results, when a pressure filtration device is used, solid fine particles can be separated to an average particle size of about 80 to 90 μm, but the average particle size is further reduced, for example, 10 μm. In the following cases, it was found that the solid fine particles were clogged in the filter medium, and the solid fine particles could not be efficiently separated and filtered. Further, as described in the prior art, the solid fine particles cannot be separated even if the suspension is diluted with a developing solvent such as water or the like by simple operation such as centrifugation.

  The present inventor has found that the viscosity of the suspension is high and there is almost no difference in specific gravity between the mixed liquid of the dispersion medium and the developing solvent and the solid fine particles, which is an obstacle to separation. Therefore, the present inventor uses alcohols and ketones as a suspension dilution to reduce the viscosity of the suspension and increase the specific gravity difference between the mixture and the solid particulates, thereby reducing the solid particulates. Attempt to separate. As a result, it was found that even solid fine particles of 10 μm or less can be separated by centrifugal force. The present invention has been developed based on such knowledge.

  That is, the functional resin powder manufacturing system 10 of the present embodiment heats a functional resin composition containing polyethylene as a thermoplastic resin and its dispersion medium (for example, polyethylene glycol) as shown in FIG. , Mixing to obtain a kneaded product of both of them, a developing solvent (for example, water) is added to the kneaded product from the kneading machine 11, the kneaded product and the developing solvent are mixed, cooled, and in the developing solvent. First stirrer that forms solid fine particles (hereinafter simply referred to as “solid fine particles” as necessary) from a functional resin composition and prepares a suspension in which a dispersion medium is dissolved in a developing solvent 12, a diluent tank 13 for storing a diluent (for example, methanol solution) for diluting the suspension, and a diluted suspension obtained by diluting the suspension of the first stirring device 12 with the diluent in the diluent tank 13 1st pump to send 1 A centrifugal separator 15 that collects and collects solid particulates from a mixture of a dispersion medium, a developing solvent, and a diluent by centrifugal force, and recovers the diluted suspension received from the first pump 14; The solid fine particles from 15 are added with a cleaning liquid (for example, washing water) to wash and re-slurry the solid fine particles, and the solid fine particles from the second stirrer 16 are wet-classified. A classifying device 17 obtained as a functional resin powder composed of solid fine particles having a desired particle size range, and a third agitating device 18 for stirring and cleaning the functional resin powder from the classifying device 17 in washing water; The centrifugal filtration device 19 for centrifuging the suspension of the functional resin powder from the third stirring device 18 and washing the functional resin powder with washing water, and the functional resin powder from the centrifugal filtration device 19 Dryer 20 to dry the body It includes, and is configured to produce a functional resin powder from the functional resin composition.

  As the kneading machine 11, various types such as a conventionally known extruder can be used. The kneader 11 receives the functional resin composition from the supply source 11A and the dispersion medium from the supply source 11B, and the functional resin composition has a temperature equal to or higher than its melting point (for example, 220 to 240 ° C.). Is heated to knead the functional resin composition and the dispersion medium to prepare a kneaded product in which the functional resin composition is dispersed in the form of fine particles in the dispersion medium. By this kneading operation, the functional resin composition is dispersed in the form of fine particles in the dispersion medium. The kneader 11 supplies the kneaded material in a molten state to the first stirring device 12.

  The first stirrer 12 receives the kneaded material from the kneader 11 and also receives the developing solvent from its supply source 12A, stirs the kneaded material and the developing solvent, and solids fine particles (10 μm from the functional resin composition). Hereinafter, for example, a dispersion medium is dissolved in a developing solvent while cooling while forming an average particle diameter of 5 to 7 μm, and then cooled to prepare a suspension in which solid fine particles are suspended in the developing solvent. This suspension is diluted with the diluent from the diluent tank 13 when supplied to the centrifuge 15 via the first pump 14. The diluted suspension (hereinafter referred to as “diluted suspension”) is reduced in viscosity by addition of a diluent and mixed with solid fine particles and a mixture (a mixture of a dispersion medium, a developing solvent and a diluent). Therefore, the solid fine particles are easily separated and settled in the mixture of the dispersion medium, the developing solvent, and the diluent in the centrifugal separator 15. The diluting solution is not particularly limited as long as it can reduce the viscosity of the suspension and increase the specific gravity difference between the solid fine particles and the mixed solution. Is preferred. In this embodiment, the diluted solution is added in the same volume as the developing solvent.

  In the present embodiment, as the centrifugal separator 15, for example, a separation plate type decanter is used as shown in FIG. 2. Therefore, in the following, the centrifugal separator 15 will be described as the separation plate type decanter 15. As shown in the figure, the separation plate type decanter 15 includes a rotating body 15A having a straight body portion having a large diameter and a cone portion gradually reducing the diameter from the straight body portion, and a right end of the rotating body 15A. A screw conveyor 15B inserted from the center of the surface according to the shaft core, and a speed reducer 15C that rotates the rotating body 15A and the screw conveyor 15B at a predetermined speed difference. The rotating suspension 15A and the screw conveyor 15B The solid-liquid separation is performed in the separation chamber 15D. The solid fine particles settled and separated in the separation chamber 15D by centrifugal force are, as indicated by an arrow X in the figure, from the hole formed in the vicinity of the left end of the separation chamber 15D to the external second stirring device 16 (see FIG. 1). Is discharged. Further, the clarified liquid separated in the separation chamber 15D is discharged from the hole formed in the right end surface of the separation chamber 15D to the external distillation apparatus 21 (see FIG. 1) as indicated by an arrow Y in FIG.

  As shown in FIG. 2, the screw conveyor 15 </ b> B has a shaft portion and screw blades formed in a spiral shape on the outer peripheral surface of the shaft portion, and conveys solid particulates with the screw blade. A hollow portion serving as a liquid supply chamber 15E is formed in the right half of the shaft portion of the screw conveyor 15G, and a plurality of holes are formed in the vicinity of the left end of the liquid supply chamber 15E at predetermined intervals along the peripheral surface. ing. A liquid supply pipe 15F is inserted into the liquid supply chamber 15E from the right end according to the axial center, and a diluted suspension is supplied from the liquid supply pipe 15F as indicated by an arrow Z in FIG. As shown by an arrow U in the figure, the diluted suspension is dispersed from the hole into the separation chamber 15D by centrifugal force. In the separation chamber 15D, a plurality of separation plates 15G are attached in the axial direction over the entire outer peripheral surface of the shaft portion of the screw conveyor 15B. These separating plates 15g are mounted in a radial manner inclining from the radial direction of the shaft portion, and the screw blades of the screw conveyor 15B are arranged on the outer peripheral surface of these separating plates 15G.

  Accordingly, when the diluted suspension is supplied from the liquid supply pipe 15F, the diluted suspension is dispersed into the separation chamber 15D from the hole of the liquid supply chamber 15E. In the separation chamber 15D, the diluted suspension forms a spiral flow along the screw blades of the screw conveyor 15G, and enters the gap between the separation plates 15G while being accelerated. Here, the clear supernatant liquid enters the separation chamber 15D. It is discharged as a separation liquid to the outside through the hole at the right end. On the other hand, the solid fine particles separated in the separation chamber 15D move toward the inner peripheral surface of the rotating body 15A along the separation plate 15G, and are deposited along the inner peripheral surface. The deposited solid fine particles are transported to the left cone portion of the rotating body 15A by the action of the screw conveyor 15B rotating at a slightly slower speed than the rotating body 15A, and are discharged to the outside from the hole of the separation chamber 15D. The solid fine particles immediately before discharge are in a region where the clear liquid does not reach, and are continuously discharged to the outside as a cake with a small liquid content.

  Since the suspension supplied from the first stirring device 12 to the separation plate type decanter 15 has almost no specific gravity difference between the mixed liquid of the dispersion medium and the developing solvent and the solid fine particles as described above, and has a high viscosity, As it is, it is difficult to separate the solid fine particles by the separation plate decanter 15. However, in this embodiment, since the suspension is diluted with a diluent in advance to reduce the viscosity, and the specific gravity difference between the solid particles and the mixed solution is increased, the solid plate fine particles are mixed by the separator decanter 15. Centrifugal sedimentation can be performed from the liquid to separate the liquid. In addition, since the separation plate type decanter 15 can perform solid-liquid separation continuously, solid-liquid separation can be performed very efficiently as compared with a batch-type device such as a pressure filtration device.

  The solid fine particles are supplied from the separation plate decanter 15 to the second stirring device 16, and the separation liquid is supplied from the separation plate decanter 15 to the distillation device 21.

  The second stirring device 16 stirs the solid fine particles supplied from the separation plate decanter 15 and the washing water supplied from the washing water supply source 22 to form a reslurry and wash the solid fine particles. Can do. The reslurry is supplied to the classifier 17 by the second pump 23 disposed on the downstream side of the second agitator 16.

The distillation apparatus 21 distills the separation liquid (mixed liquid of the dispersion medium, the developing solvent, and the dilution liquid) received from the separation plate decanter 15 and collects the dilution liquid having a low boiling point (in this embodiment, a methanol solution). The diluent is supplied to the dilution tank 13 from the distillation apparatus 21 through the pump 21A. This diluent is used repeatedly for dilution of the suspension.

  The classification device 17 is configured as, for example, a vibration wet separation device, and selects a functional resin powder composed of solid fine particles having a desired particle size. The suspension containing the desired solid fine particles obtained by the classification device 17 is supplied to the third stirring device 18 by the third pump 24. The third agitator 18 agitates the suspension supplied from the classifier 17 to uniformly disperse the solid fine particles in the washing water. This suspension is supplied to the centrifugal filtration device 19 by a fourth pump 25 disposed on the downstream side of the third stirring device 18.

  For example, as shown in FIG. 3, the centrifugal filtration device 19 is configured as a basket type centrifugal filtration washing apparatus. As shown in the figure, the centrifugal filtration device 19 is in communication with a rotating basket 191 having a filter medium 191A stretched on its inner peripheral surface, a rotating shaft 192 for rotating the rotating basket 191 and the filtrate side of the rotating basket 191. A siphon chamber 194 communicating through the hole 193, a siphon tube 195 capable of adjusting the immersion depth for sucking and discharging the filtrate in the siphon chamber 194, a supply tube 196 for supplying suspension into the rotating basket 191, and a rotation A scraping knife 197 for scraping the cake layer of solid particulates formed on the inner peripheral surface of the basket 191, and a discharge chute 198 for discharging the solid particulates scraped by the scraping knife 197 as a functional resin powder; And rotating the rotating basket 191 to apply a predetermined centrifugal force to the suspension to separate and remove the washing water from the suspension.

  The supply pipe 196 is also connected to a washing water source 22 (see FIG. 1). After a cake layer of functional resin powder is formed on the filter medium 191A by centrifugal filtration, washing water is supplied to wash the cake layer. It is like that. The siphon pipe 195 is connected to the drain pipe 26 (see FIG. 1), and discharges the filtrate of the centrifugal filtration device 19 as waste water. In FIG. 3, reference numeral 199 denotes a rotating shaft that adjusts the angle of the scraping knife 197 with respect to the filter medium 191.

  When the washing water is separated and removed from the suspension by the centrifugal filtration device 19, for example, a centrifugal force of 100 to 1500 G is applied to the functional resin powder by rotating the rotating basket 191. Almost all adhering moisture can be removed, and the moisture content of the functional resin powder cake layer can be reduced to about 5 to 10%. If the applied centrifugal force is less than 100G, the moisture content cannot be reduced sufficiently, the load in the next drying step increases, and it takes a long time to dry. Almost no difference. Moreover, since the centrifugal filtration device 19 is configured as a basket-type centrifugal filtration and washing device, it is hermetically sealed, can prevent the entry of impurities from the outside, and can obtain a high-purity functional resin powder. it can. In this centrifugal filtration device 19, after the moisture content of the functional resin powder is reduced to about 5 to 10%, the functional resin powder is supplied to the dryer 20.

  The dryer 20 is configured as a double cone dryer, for example, as shown in FIG. As shown in the figure, the dryer 20 includes a double-cone vacuuming vessel 20A and a crushing blade 20B provided therein, and a hot water supply source 27 is connected to the vessel 20A. ing. In the dryer 20, the functional resin powder containing moisture in the container 20A is stirred by the crushing blade 20B, and the functional resin powder is heated and dried by the hot water supplied to the jacket portion of the container 20A. To do. In this dryer 20, the functional resin powder is dried, and the water content is reduced to about 0.5%.

  As described above, according to the present embodiment, when the solid particles of the functional resin composition are separated and recovered from the suspension prepared by adding the developing solvent to the kneaded product of the functional resin composition and the dispersion medium. In addition, the diluent in the diluent tank 13 is added to a suspension having a high viscosity and almost no specific gravity difference between the mixed solution and the solid fine particles, thereby reducing the viscosity of the suspension and solid fine particles. And the liquid mixture is increased in specific gravity to facilitate separation of the solid particulates from the liquid mixture, and the separation suspension decanter 15 is used to facilitate solid-liquid separation of the diluted suspension, so that the average particle size is 5 to 7 μm. Even in the case of solid fine particles, functional resin powders can be obtained by continuous and efficient separation. Further, since the separation plate type decanter 15 does not have a filter medium, the solid fine particles can be smoothly solid-liquid separated without clogging unlike a pressure filtration device. Therefore, even a functional resin powder having a small average particle diameter such as a toner can be reliably produced from the functional resin composition.

  Further, according to the present embodiment, the distillation apparatus 21 is provided on the downstream side of the separation plate decanter 15 so that the diluting liquid can be collected and used repeatedly, so that the waste liquid can be significantly reduced.

  The present invention is not limited to the embodiment described above, and the design of each component can be appropriately changed as necessary, and appropriate devices can be added as necessary. In the above embodiment, methanol is used as the diluent, but alcohols such as ethanol, ketones, and the like can also be used. Moreover, in the said embodiment, although the separation plate type | mold decanter is used as a centrifuge, another type of centrifuge can also be used.

  The present invention can be suitably used for producing functional resin powders imparted with various physical and chemical properties.

It is a block diagram which shows one Embodiment of the manufacturing system of the functional resin powder of this invention. It is sectional drawing of the centrifuge shown in FIG. It is a block diagram which shows the centrifugal filtration apparatus shown in FIG.

Explanation of symbols

10 Functional resin powder production system 13 Diluent tank (diluent addition means)
14 First pump (diluent addition means)
15 Separation plate type decanter (centrifuge)
21 Distillation equipment

Claims (8)

A functional resin composition containing at least a thermoplastic resin and exhibiting a predetermined function and a dispersion medium incompatible with the functional resin composition are mixed while being heated to a temperature equal to or higher than the melting point of the functional resin composition. above, and stirred with the mixture to a poor solvent for the functional resin composition added developing solvent is a good solvent for the dispersion medium to the mixture, in which the developing solvent was added The mixture is cooled to a temperature not higher than the melting point of the functional resin composition, and the dispersion medium is dissolved in the developing solvent during this period to form a suspension of the functional resin composition. A functional resin powder production system for separating and recovering a powder of a resin composition, wherein the suspension has a specific gravity and viscosity smaller than that of a mixture of the dispersion medium and the developing solvent, and the mixture after dilution Liquid and the functional resin composition A diluent addition means for adding the diluent to expand the heavy difference diluted mixture to expand specific gravity difference between being diluted with the diluent the mixed solution specific gravity and viscosity is smaller than and the functional resin composition And a powder recovery means for recovering the functional resin composition as a functional resin powder, wherein the powder recovery means centrifuges the functional resin powder from the diluted mixed solution by centrifugation. A functional resin powder manufacturing system characterized by   2. The functional resin powder production system according to claim 1, wherein a distillation apparatus for collecting the diluted solution is provided on the downstream side of the centrifuge.   The system for producing functional resin powder according to claim 2, wherein the diluting liquid adding means and the distillation apparatus are connected. A functional resin composition containing at least a thermoplastic resin and exhibiting a predetermined function and a dispersion medium incompatible with the functional resin composition are mixed while being heated to a temperature equal to or higher than the melting point of the functional resin composition. above, and stirred with the mixture to a poor solvent for the functional resin composition added developing solvent is a good solvent for the dispersion medium to the mixture, in which the developing solvent was added The mixture is cooled to a temperature not higher than the melting point of the functional resin composition, and the dispersion medium is dissolved in the developing solvent during this period to form a suspension of the functional resin composition. A method for producing a functional resin powder by separating and recovering a powder of a resin composition, wherein the suspension has a specific gravity and viscosity smaller than that of a mixture of the dispersion medium and the developing solvent and is diluted. The above mixed liquid and the above functional resin A step of dilution with diluent to enlarge the difference in specific gravity between the Narubutsu, diluted to enlarge difference in specific gravity between and it is diluted with the diluent the mixed solution specific gravity and viscosity is smaller than and the functional resin composition And a step of centrifugal sedimentation of the functional resin composition as a functional resin powder from the mixed solution .   The method for producing a functional resin powder according to claim 4, further comprising a step of distilling the separation liquid separated by the centrifugal sedimentation and recovering the dilution liquid. The water is used as the developing solvent, method for producing a functional resin powder according to claim 4 or claim 5, characterized by using the A alcohol or ketone as the above diluent.   The method for producing a functional resin powder according to any one of claims 4 to 6, wherein the functional resin powder having an average particle size of 10 µm or less is collected.   The method for producing a functional resin powder according to any one of claims 4 to 7, wherein the functional resin powder is a toner.

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