JP2016155054A - Wet disperser - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wet disperser where contamination (intrusion of foreign matter) is hardly caused and fine particles can be uniformly dispersed in a short time and which can be operated in energy saving and space saving.SOLUTION: In a wet disperser 1,: fine particles in a mixture including at least the fine particles and a dispersion medium are disposed; a flow passage extending from an inflow port to an outflow port is equipped; the flow passage 13 has a dispersion portion 11 disposed on the way of the flow passage 13; the dispersion portion 11 has a dispersion portion inner flow passage 15 forming a part of the flow passage 13; the dispersion portion inner flow passage 15 includes a gearshift region 7 changing the flow rate of the mixture by narrowing the space of the dispersion portion inner flow passage 15 in the flowing direction F of the mixture in the dispersion portion inner flow passage 15; and the space t at the narrowest portion of the dispersion portion inner flow passage 15 in the gearshift region 7 is 100 μm or less.SELECTED DRAWING: Figure 1A

Description

  The present invention relates to a wet disperser in which fine particles in a mixture containing at least one fine particle selected from the group consisting of primary particles and aggregates contained in a mixture and at least a dispersion medium are dispersed. More specifically, the present invention relates to a wet disperser that has almost no contamination (contamination of foreign matter), can uniformly disperse fine particles in a short time, and can be operated with reduced energy and space.

  Fine particles with a median diameter of 1 to 500 nm are used for catalysts, catalyst carriers, conductive inks, sensors, luminescent materials, chemicals, etc. due to their extremely large specific surface area and their unique physical properties different from those of bulk. It is widely used as a functional material or an intermediate or precursor of a functional material.

  In order to effectively develop functions unique to the fine particles (such as a large specific surface area and physical properties different from the bulk), it is important to control the particle size of the fine particles, control the aggregation state of the fine particles, control the particle size distribution, and the like. The control of the particle size distribution is to control the particle size of the fine particles to be uniform in the dispersion system.

  Conventionally, high-speed homogenizers, high-pressure homogenizers, ball mills, bead mills, jet mills and the like have been used as a method for dispersing fine particles in a dispersion medium.

  However, the method of dispersing fine particles in a dispersion medium using a high-rotation type homogenizer cannot uniformly disperse the fine particles, and controls the particle size of the fine particles, the control of the aggregation state, and the control of the particle size distribution. There were times when it was not possible to do.

  Further, when the fine particles are dispersed in the dispersion medium using a high-pressure homogenizer, there is a risk that the fine particles are heated by the high pressure and the physical properties of the fine particles are changed. For example, a method for producing drug superabrasive particles having an average particle size of 10 nm to 1000 nm, which is emulsified at a processing pressure of 3.5 to 275 MPa using a high-pressure homogenizer, is disclosed (Patent Document 1). However, the high-pressure homogenizer used in the manufacturing method of Patent Document 1 has high energy consumption and requires a cooling operation. For this reason, problems have arisen in that a large amount of energy is consumed and a cooling facility for cooling work is required.

  In addition, in the method in which fine particles are dispersed in a dispersion medium using a ball mill or a bead mill, the beads are brought into contact with each other and the beads are worn, and the bead pieces caused by the wear are mixed into the raw material. Sometimes occurred. In addition, there has been a problem that the operation time of the apparatus is long and fine particles cannot be produced efficiently. And in the method of dispersing fine particles in a dispersion medium using a jet mill, since the jet mill uses a high-pressure gas, there is a problem that energy consumption is high.

  In addition, in order to solve the above-mentioned problems, various products having a fine particle dispersion process, such as the production of coating particles coated with fine particles as a base material, can be dispersed in a high degree and evenly in a short time. A wet disperser manufactured with high efficiency is disclosed (Patent Document 2). In this wet disperser, fine particles are split and dispersed by passing through an orifice provided in a slurry flow path, and further, the split fine particles are eroded and dispersed using ultrasonic waves. Therefore, unlike the bead mill or the like, the problem of contamination due to contact and wear of the beads as the grinding media hardly occurs, and the energy consumption is small.

International Publication No. 2005/013938 JP 05-168888 A

  However, the wet disperser of Patent Document 2 can be dispersed into fine particles of 1 μm to 10 μm as seen in the Examples of Patent Document 2, but the median diameter mixed in the dispersion medium is 1 to 500 nm. It was sometimes difficult to uniformly disperse the nanoparticles.

  The present invention has been made in view of such problems. According to the present invention, a wet disperser for dispersing fine particles in a mixture is provided. Since the wet disperser of the present invention is pulverized media-less, it can be dispersed with little contamination, can disperse fine particles in a short time, and the particle size of the fine particles, and the particle size The distribution can be controlled to be constant. The wet disperser of the present invention can disperse the fine particles in the dispersion medium in a short time. Moreover, since the wet disperser of the present invention does not require cooling equipment for cooling work, it can be installed in a narrow space. Furthermore, a complex flow field generated in a mixture containing at least fine particles and a dispersion medium, that is, mixed shrinkage flow, shear flow, elongation flow, vibration flow, and the like can be used simultaneously, and the fine particles in the dispersion medium can be uniformly dispersed. The present invention distributes all of the agglomerated particles at a relatively low pressure, depending on their size, through a nano-micron gap, which is normally uncontrollable, with a dispersion principle that gives a very rapid flow rate variation. Including.

  According to the present invention, the following wet disperser is provided.

[1] A wet disperser for dispersing the fine particles in a mixture containing at least one kind of fine particles selected from the group consisting of primary particles and aggregates and at least a dispersion medium, the flow of the mixture A flow path extending from the flow inlet to the flow outlet, the flow path having a dispersion portion provided in the middle of the flow path, A flow path in the dispersion part that forms a part of the flow path, and the flow path in the dispersion part narrows the gap in the flow path in the dispersion part in the direction in which the mixture of the flow path in the dispersion part flows, A wet disperser including a speed change zone for changing a flow rate of the mixture, wherein a gap in a portion where the flow path in the dispersion part is the narrowest in the speed change zone is 100 μm or less.

[2] The wet disperser according to [1], wherein the primary particles include a particulate substance or a fibrous substance.

[3] The wet disperser according to the above [1] or [2], wherein the fine particles are dispersed as nanoparticles having a median diameter of 1 to 500 nm in the mixture after the dispersion treatment.

[4] As a fine particle after dispersion treatment having a median diameter of 500 nm to 10 μm in the mixture after dispersion treatment, or as a nanofiber having a fiber diameter of 1 to 100 nm in the mixture after dispersion treatment, The wet disperser according to [1] or [2], which is dispersed.

[5] The dispersion portion is provided with a passage hole on the downstream side of the speed change zone, and the passage hole is provided at a position where the circumference of the dispersion portion and the passage hole are equal in length. The wet disperser according to any one of [1] to [4].

[6] The wet disperser according to any one of [1] to [5], wherein a gap of the flow path in the dispersion section excluding the speed change area gradually decreases in a direction in which the mixture flows.

[7] The wet disperser according to any one of [1] to [6], wherein the flow path in the dispersion section includes a plurality of the speed change zones in a direction in which the mixture flows.

[8] The other gap provided in a portion where the flow path in the dispersion portion in the one shift region on the upstream side in the flow direction of the mixture is the narrowest is provided on the downstream side of the one shift region. The wet disperser according to the above [7], wherein the flow path in the dispersion section in the speed change zone is wider than the gap of the narrowest portion.

[9] The dispersion portion is provided with a passage hole upstream of the speed change zone, and the passage hole is provided at a position where the length of the periphery of the dispersion portion and the passage hole are equal. The wet disperser according to any one of [1] to [4].

[10] The dispersion section includes a plurality of transmission area units including at least one or more of the transmission areas in a direction in which the mixture flows, and each of the plurality of transmission area units includes the transmission area units between each other. [9] The transmission zone unit passage hole through which the mixture passes is provided, and the plurality of transmission zone units are arranged in a stacked state so that the directions in which the mixture flows are parallel to each other. The wet disperser described in 1.

[11] The wet disperser according to [10], wherein the plurality of speed change area units are provided on a surface parallel to a surface on which the passage hole is formed.

  According to the wet disperser of the present invention, a pulverizing medium is unnecessary, energy saving, and dispersion of fine particles with almost no contamination can be performed in a short time. In addition, since complex flow fields generated in a mixture containing at least fine particles and a dispersion medium, that is, mixed contraction flow, shear flow, elongation flow, vibration flow, etc. can be used simultaneously, the particle size and particle size distribution of the fine particles are constant. Can be controlled. Furthermore, unlike conventional dispersion processing using a high-pressure homogenizer, fine particles do not become hot during the dispersion treatment, so there is almost no risk of changes in the physical properties of the fine particles, and there is no need for equipment such as means for cooling the fine particles. Therefore, it can be installed in a limited space. Since the wet disperser can be operated in a short time and with energy saving, it is excellent in productivity and workability.

  Moreover, the wet disperser of this invention can also pass the mixture containing at least microparticles | fine-particles and a dispersion medium in multiple times with respect to one wet disperser by the aggregation state of microparticles | fine-particles. In addition, the wet disperser of the present invention can be used by connecting a plurality of wet dispersers in series. That is, the mixture passes through each wet disperser connected in series with the first wet disperser, the second wet disperser, and the third wet disperser. In addition, the wet disperser of the present invention can be designed in various ways such as processing a large amount of mixture by arranging a plurality of wet dispersers in parallel.

  The wet disperser of the present invention can also be used for emulsification dispersion. That is, a dispersion medium containing at least a dispersion medium and a dispersoid, both of which are liquids, and pre-emulsified with a homomixer or the like, for example, a dispersoid having an average particle diameter of droplets of dispersoid of 50 μm or less. A uniform emulsion (mixture after dispersion treatment) dispersed in a dispersion medium can be obtained. Here, the “dispersoid droplet” refers to a liquid phase of a dispersion medium whose entire surface is an interface between the dispersoid and the dispersion medium.

  The wet disperser of the present invention can also be used for dispersion and destruction of biocells such as microorganisms and cells.

  Furthermore, the wet disperser of the present invention can also disintegrate agglomerates of fine particles (consolidated fine particles) weakly consolidated by sintering or fusion. The consolidated fine particles are particles that do not contain electrolyte and aggregating agent molecules between the particles, and are the same body that looks like aggregated particles by growing necking due to chemical bonds of the same composition.

It is a vertical sectional view of a wet disperser showing typically a first embodiment of a wet disperser of the present invention, and is a figure which saw through a part of channel. FIG. 1B is a plan view of FIG. 1A viewed from the direction of arrow X, and is a view seen through a part of a flow path. In FIG. 1A, it is an enlarged view of the area | region (alpha) enclosed with the broken line. 1B is a vertical sectional view of a wet disperser schematically showing a state when the mixture before dispersion treatment is fed to the wet disperser of the first embodiment shown in FIG. is there. It is the elements on larger scale of the vertical cross section of the wet disperser which show typically a second embodiment of the wet disperser of the present invention, and is a figure which saw through a part of channel. It is the vertical sectional view of the wet disperser showing typically a third embodiment of the wet disperser of the present invention, and is a figure which saw through a part of channel. FIG. 3A is a plan view of FIG. 3A viewed from the direction of arrow X, and is a view seen through a part of a flow path. FIG. 3A is an enlarged view of a region β surrounded by a broken line in FIG. 3A. It is the elements on larger scale of the vertical sectional view of a wet disperser showing a 4th embodiment of a wet disperser of the present invention typically, and is a figure which saw through a part of channel. It is the elements on larger scale of the vertical cross section of the wet disperser which show typically 5th embodiment of the wet disperser of this invention, and is the figure which saw through a part of flow path. It is the vertical sectional view of a wet disperser showing typically a 6th embodiment of a wet disperser of the present invention, and is a figure which saw through a part of channel. FIG. 6A is a plan view of FIG. 6A viewed from the direction of arrow X, and is a view seen through an odd-numbered shift area unit. 6A is a plan view of FIG. 6A viewed from the direction of arrow X, and is a view seen through the even-numbered speed change zone unit. FIG. FIG. 6A is an enlarged view of a region γ surrounded by a broken line. It is the vertical sectional view of a wet disperser showing typically the case where the wet disperser of the present invention is further provided with a vibrator, and is a figure which saw through a part of channel. It is explanatory drawing which shows typically the dispersion process using the wet disperser of this invention. It is a graph which shows the particle diameter distribution of the mixture before carrying out the dispersion process of the wet disperser of this invention, the mixture after the dispersion process of the wet disperser of this invention, and the mixture after carrying out the dispersion process by the conventional ultrasonic homogenizer.

  Embodiments of the present invention will be described below, but the present invention is not limited to the following embodiments. Accordingly, it is understood that modifications, improvements, and the like to the following embodiments are also included in the scope of the present invention based on ordinary knowledge of those skilled in the art without departing from the spirit of the present invention. Should be.

(1) Wet disperser:
1st Embodiment of the wet disperser of this invention is the wet disperser 1 as shown to FIG. 1A-FIG. 1D. FIG. 1A is a vertical sectional view of a wet disperser schematically showing a first embodiment of a wet disperser of the present invention, and is a view seen through a part of a flow path. FIG. 1B is a plan view of FIG. 1A viewed from the direction of arrow X, and is a view seen through a part of the flow path. FIG. 1C is an enlarged view of a region α surrounded by a broken line in FIG. 1A. FIG. 1D is a vertical cross-sectional view of the wet disperser schematically showing a state when the pre-dispersion mixture is fed to the wet disperser of the first embodiment shown in FIG. 1A. FIG.

  As shown in FIG. 1A to FIG. 1D, the wet disperser 1 of the first embodiment has an inlet 3 and an outlet 5 serving as a channel 13 for the mixture, and extends from the inlet 3 to the outlet 5. 13 is provided. The flow path 13 has a dispersion part 11 provided in the middle of the flow path 13, and the dispersion part 11 has a flow path 15 in the dispersion part that forms a part of the flow path 13. Moreover, the flow path 15 in the dispersion part includes the speed change zone 7 in which the flow rate of the mixture is changed by narrowing the gap of the flow path in the dispersion part in the direction F in which the mixture in the flow path 15 in the dispersion part flows. Further, the gap t in the portion where the flow path 15 in the dispersion portion in the speed change zone 7 is the narrowest is 100 μm or less. Further, the gap between the front and rear dispersion passages 15 in the direction F in which the mixture in the transmission zone 7 flows is wider than the gap between the dispersion passages 15 in the transmission zone 7. In FIG. 1B, the mixture flows from the periphery 16 of the dispersing portion toward the geometric center of gravity O of the passage hole, but there is no limitation on the direction F in which the mixture flows. For example, the mixture may be configured to flow in the direction opposite to the direction of arrow F shown in FIG. 1B.

  In the wet disperser of the present embodiment, in the speed change zone 7, the gap t of the portion where the flow path 15 in the dispersive portion is the narrowest is 100 μm or less. Further, the gap t is preferably 50 μm or less, and more preferably 10 μm or less. The gap t is a gap having a width through which at least the mixture before dispersion treatment flows, although it depends on the pressure condition. By comprising in this way, a complicated flow field arises uniformly with respect to the mixture before a dispersion process by the viscosity of the mixture before a dispersion process. In the speed change zone 7, if the gap t of the portion where the flow path 15 in the dispersion part is the narrowest is too wide, the complicated flow field generated by the viscosity of the mixture before dispersion treatment is generated only in a part of the mixture before dispersion treatment. There is. Here, the “gap t of the part where the flow path 15 in the dispersion part is the narrowest” means that the width of the flow path 15 in the dispersion part in the direction perpendicular to the direction F in which the mixture in the vertical section of the wet disperser 1 flows. It is the narrowest part.

  According to the wet disperser of the present embodiment, there is no need for a pulverizing medium for pulverizing the fine particles before the dispersion treatment, and the fine particles before the dispersion treatment are produced in a short time and almost without causing contamination. It is possible to disperse the particles in the dispersion medium as nanoparticles or nanofibers. Hereinafter, the fine particles before the dispersion treatment may be referred to as “fine particles before the dispersion treatment”, and the fine particles after the dispersion treatment of the fine particles before the dispersion treatment may be referred to as “fine particles after the dispersion treatment”. In addition, when the fine particles after dispersion treatment are particulate substances having a median diameter of 1 to 500 nm, they may be referred to as “nanofine particles”, and when the particles after dispersion treatment are fibrous substances, they may be referred to as “nanofibers”. is there. In addition, “a mixture containing at least one kind of fine particles before dispersion treatment selected from the group consisting of primary particles and aggregates and a dispersion medium” before dispersion treatment is referred to as “mixture before dispersion treatment”. Sometimes. In addition, the mixture after the mixture is subjected to dispersion treatment may be referred to as “mixture after dispersion treatment”. The fine particles after the dispersion treatment and the mixture after the dispersion treatment are the fine particles and the mixture after the fine particles before the dispersion treatment and the mixture before the dispersion treatment pass through the wet disperser and are discharged from the outlet. . The fine particles before the dispersion treatment, the fine particles being dispersed, and the fine particles after the dispersion treatment are sometimes simply referred to as “fine particles”. Similarly, the mixture before the dispersion treatment, the mixture during the dispersion treatment, and the mixture after the dispersion treatment are sometimes simply referred to as “mixture”.

  As illustrated in FIGS. 1A to 1D, the in-dispersion channel 15 includes a speed change zone 7. When the mixture passes through the speed change zone 7 in which the flow path 15 in the dispersion portion is narrowed, the flow rate of the mixture increases. And when the flow path 15 in the dispersion | distribution part in the said speed change zone passes the gap | interval t of the narrowest part, the flow velocity of a mixture becomes the fastest compared with the flow velocity just before flowing into the speed change zone 7 of a mixture. . Due to such a change in the flow velocity of the mixture before the dispersion treatment, a complex flow field is generated in the mixture before the dispersion treatment, and the action of the complex flow field causes the fine particles before the dispersion treatment in the mixture before the dispersion treatment to have a constant fine particle diameter and It is dispersed in a dispersion medium as fine particles after dispersion treatment having a diameter distribution. In the wet disperser 1 of the present embodiment, a pulverizing medium used in a conventional ball mill or bead mill is not required, so that a pulverized media piece generated by abrasion of the pulverizing medium is mixed into the mixture after the dispersion treatment (contamination). There is little to do. And in the wet disperser 1 of this embodiment, since it is not necessary to use high-pressure gas etc. like wet dispersers, such as a conventional jet mill and a high-pressure homogenizer, it does not require a big energy and it is operated by energy saving. can do. Furthermore, in the wet disperser 1 of the present embodiment, unlike the dispersion treatment of the mixture before the dispersion treatment by the conventional high-pressure homogenizer, the fine particles after the dispersion treatment do not become high temperature, so that the physical properties of the fine particles may change. Since there is almost no facility for cooling fine particles, etc., it can be installed in a limited space.

  The wet disperser of the present embodiment is configured to generate a pressure difference with respect to the mixture before passing through the speed change zone and after passing through the speed change zone, thereby changing the flow rate of the mixture. For this reason, the gap u (for example, the gap of the flow path in the dispersion portion excluding the speed change zone) between the front and rear in the direction in which the mixture in the transmission area flows is the gap t in the portion where the flow path in the dispersion portion is the narrowest. It is comprised so that it may become wider. Further, depending on conditions such as pressure and the viscosity of the mixture before dispersion treatment, for example, in the flow path in the dispersion section including the speed change zone, the change in the flow velocity of the mixture flowing in the flow path in the dispersion section is about 100 to 1000 times. is there.

  Here, the speed change zone refers to a zone including a portion where the gap in the portion where the flow path in the dispersion portion is the narrowest is 100 μm or less. In FIG. 1C, the area surrounded by the broken line is the speed change area 7. In the speed change zone 7, the flow path 15 in the dispersion portion is the narrowest from the portion where the flow velocity of the mixture before dispersion treatment in the flow passage 15 in the dispersion portion before flowing into the speed change zone 7 increases compared to the flow velocity of the mixture before dispersion treatment. In comparison with the flow rate of the pre-dispersion mixture in the portion that is, it includes up to the portion where the flow rate of the pre-dispersion mixture decreases.

  The speed change zone 7 is a specific in-dispersion-part flow path 15 including a part in which the gap of the narrowest part of the in-dispersion-part flow path 15 is 100 μm or less. There is no particular limitation on the shape or the like of the speed change zone 7. As the speed change zone 7, the thing which has a convex part for narrowing the clearance gap between the flow paths 15 in a dispersion | distribution part can be mentioned as a preferable aspect. For example, the speed change area 7 shown in FIGS. 1A, 1C, and 1D has a convex portion P. By having this convex part P, the gap | interval of the flow path 15 in dispersion | distribution part becomes narrow along the shape of the convex part P, and the gap | interval of the flow path 15 in dispersion | distribution part 15 is the narrowest in the top part of the said convex part P. 100 μm or less). When the speed change area 7 has such a convex portion P, a range from one trough (hem) of the convex P to the other trough (hem) of the convex P is defined as a speed change area. 7 can be used. Further, in a cross section (cross section in a direction perpendicular to AA ′ in FIG. 1B) that is perpendicular to the flow direction F of the mixture in the flow path 15 in the dispersion section and includes the geometric center of gravity O of the passage hole 9. The cross-sectional shape of the convex portion P is preferably the following shape. It is preferable that the cross-sectional shape of the convex portion P is a triangle, a part of the cross-sectional shape is a triangle, a trapezoid, a staircase shape, a part of the cross-sectional shape is a trapezoid, a semicircular shape, and a part of the cross-sectional shape is a semicircular shape. Moreover, it is preferable that a convex part is a triangle and a trapezoid from a viewpoint of intensity | strength. A trapezoid is a quadrangle in which at least one pair of opposite sides is parallel. Further, when the cross-sectional shape of the convex portion P is a triangle, a part of the cross-sectional shape is a triangle, a trapezoid, a staircase shape, and a part of the cross-sectional shape is a trapezoid, the corner portion T may form a vertex, It may be formed in a curved shape. Hereinafter, the “cross section perpendicular to the flow direction of the mixture in the flow path in the dispersion portion and including the geometric center of gravity O of the passage hole 9” may be simply referred to as “AA ′ cross section”. .

  The inlet of the mixture before dispersion treatment is not particularly limited as long as it has a shape and structure that facilitates introduction of the mixture before dispersion treatment into the wet disperser, and a known one can be used. Further, the outlet of the mixture after dispersion treatment is not particularly limited as long as it has a shape and structure that can easily discharge the mixture after dispersion treatment to the outside of the wet disperser, and a known one can be used.

  The liquid feeding speed at which the mixture before dispersion treatment is fed from the inlet to the flow path is preferably 5 to 500 cm / s, and more preferably 10 to 100 cm / s. When the liquid feeding speed is lower than 5 cm / s, the fine particles before dispersion treatment may settle and accumulate in the flow path. If the liquid feeding speed is faster than 500 cm / s, the pressure required for liquid feeding becomes high, so the pressure resistance of the flow path and the performance of the liquid feeding pressure of the pump must be increased.

  The liquid feeding pressure for feeding the mixture before dispersion treatment from the inlet to the flow path is preferably 30 MPa or less.

  The material of the wet disperser is not particularly limited as long as it has sufficient corrosion resistance with respect to the mixture before dispersion treatment (mixture after dispersion treatment). For example, ceramic, iron, stainless steel, acrylic resin Etc. are preferred.

  In the wet disperser of the present embodiment, the primary particles as the pre-dispersion fine particles preferably include a particulate material or a fibrous material. The primary particles are preferably single crystallites or a collection of crystallites close to a single crystal, and the median diameter is preferably 1 to 500 nm. Aggregates are preferably those in which several to thousands of primary particles having a median diameter of 1 to 500 nm are aggregated by van der Waals force, Coulomb force, or the like.

  The wet disperser of the present embodiment can disperse the pre-dispersion fine particles in the dispersion medium (in the post-dispersion mixture) as nanoparticles having a median diameter of 1 to 500 nm (fine particles after the dispersion treatment). The nano-particles are aggregates having a median diameter of 1 to 500 nm, which are aggregates of primary particles having a median diameter of 1 to 500 nm and primary particles having a median diameter of 1 to 500 nm.

  The wet disperser of this embodiment can also perform a dispersion treatment of a mixture before dispersion treatment including particles larger than the fine particles after dispersion treatment, for example, pre-dispersion fine particles having a median diameter of several hundred μm to several mm. By carrying out such a dispersion treatment of the mixture before the dispersion treatment, for example, a mixture after the dispersion treatment containing fine particles after the dispersion treatment having a median diameter of 500 nm to 10 μm can be obtained. Even when such fine particles after the dispersion treatment are dispersed in the dispersion medium, the gap in the portion where the flow path in the dispersion portion in the speed change zone is the narrowest is 100 μm or less.

  When the pre-dispersion fine particles are nanofiber aggregates, the wet disperser of the present embodiment dissociates at least a part of nanofiber aggregation (entanglement), and forms nanofibers in a dispersion medium (dispersion treatment). It can also be dispersed in a post-mixture). As nanofibers, those having a fiber diameter of 1 to 100 nm and a length of 100 times or more of the fiber diameter are preferable. Even when such fine particles after the dispersion treatment are dispersed in the dispersion medium, the gap in the portion where the flow path in the dispersion portion in the speed change zone is the narrowest is 100 μm or less.

  The wet disperser of the present invention can also be used for emulsification dispersion. That is, a dispersion medium containing at least a dispersion medium and a dispersoid, both of which are liquids and pre-emulsified with a homogenizer or the like, is dispersed in, for example, a dispersoid having an average particle size of droplets of dispersoid of 50 μm or less A uniform emulsion (mixture after dispersion treatment) dispersed in a medium can be obtained. Here, the “dispersoid droplet” refers to a liquid phase of a dispersion medium whose entire surface is an interface between the dispersoid and the dispersion medium. Examples of emulsification dispersion include synthesis of latex particles.

  In addition, the wet disperser of the present embodiment can also be used for dispersion and destruction of biocells such as microorganisms and cells. That is, the wet disperser according to the present embodiment is capable of energy-saving and dispersion-free dispersion in a short time even for a pre-dispersion mixture containing biocells or biocell aggregates as a dispersoid. In addition, regarding the pre-dispersion mixture containing biocell or biocell aggregate as a dispersoid, at least a part of the biocell can be destroyed in the dispersion process.

  As shown in FIG. 1B, the dispersion portion 11 in the wet disperser 1 of the present embodiment is a surface parallel to the flow direction F of the mixture, and at least a part of the peripheral edge 12 is defined by the speed change zone 7. It is preferable that it has D1. Further, the dispersion part 11 in the wet disperser 1 of the present embodiment is a surface parallel to the flow direction of the mixture, and all of the peripheral edge 12 thereof has a surface D1 defined by the speed change zone 7. preferable. And it is preferable that the shape of the surface D1 is circular shape or polygonal shape. With this configuration, the complex flow field generated in the mixture by passing through the speed change zone 7, that is, the mixed contraction flow, shear flow, extension flow, vibration flow, and the like can be efficiently used at the same time. The fine particles before dispersion treatment can be dispersed in a dispersion medium (mixture after dispersion treatment).

  As shown in FIG. 1B, the dispersion part 11 in the wet disperser 1 of the present embodiment further has a surface D2 that is parallel to the surface D1 parallel to the flow direction of the mixture, on the outer peripheral side of the speed change zone 7. May be. When the dispersion part 11 further includes the surface D2, a plurality of slits (not shown) may be formed from the peripheral edge 14 of the surface D2 toward the geometric center of gravity O. By forming such slits, the mixture can be easily fed out in the flow direction F of the mixture (guided easily).

  As shown in FIGS. 1A to 1D and FIGS. 3A to 3C, the dispersing portion 11 in the wet disperser 1 of the present embodiment is provided with a passage hole 9 on the downstream side of the transmission area 7. The passage hole 9 is preferably provided at a position where the lengths L from the periphery 16 of the dispersion portion to the passage hole 9 are equal. The “length L from the periphery 16 of the dispersion part 11 to the passage hole 9” means a perpendicular line drawn from the geometric center of gravity O of the passage hole 9 to the flow path 15 in the dispersion part facing the passage hole 9. It is the length L from the foot M to the periphery 16 of the dispersion part. Since the pre-dispersion mixture flows from the periphery 16 of the dispersion part 11 into the dispersion part flow path 15, this configuration makes it possible for the pre-dispersion mixture to be a complicated flow field, that is, mixed by the shift zone 7. The contracted flow, shear flow, extension flow, vibration flow and the like can be generated uniformly.

  Further, as shown in FIGS. 6A to 6D, the dispersion portion 11f in the wet disperser of the present embodiment is provided with a passage hole 9f upstream of the speed change zone 7f, and the passage hole 9f is dispersed. It is also preferable that the length of the periphery of the portion 11f and the passage hole 9f be equal to each other. The “length L from the periphery of the dispersion portion 11f to the passage hole 9f” means a foot of a perpendicular line from the geometric center of gravity O of the passage hole 9f to the flow passage 15f in the dispersion portion facing the passage hole 9f. To the circumference of the dispersion part 11f. Since the pre-dispersion mixture flows from the periphery of the dispersion portion 11f into the dispersion-port flow path 15f, the mixture before the dispersion treatment is mixed with the pre-dispersion mixture by the speed change zone 7f. The contraction flow, shear flow, extension flow, vibration flow and the like can be generated uniformly.

  In the wet disperser 1 of the present embodiment, when a passage hole is provided in the dispersion portion, the pressure applied to the mixture before dispersion treatment can be adjusted. The passage hole is preferably formed in a columnar shape, a nozzle shape, and an orifice shape, and particularly preferably formed in an orifice shape. When the passage hole is formed in an orifice shape, the back pressure generated when the pre-dispersion mixture passes through the passage hole is smaller than when the passage hole is formed in a columnar shape or a nozzle shape. be able to. Here, “the passage hole is formed in a cylindrical shape” means that the opening of the passage hole is cylindrical, that is, the size of the opening of the passage hole is from the upstream side to the downstream side of the passage hole. It means that it is constant. Further, “the passage hole is formed in a nozzle shape” means the following. The flow path in which the passage hole is formed has a first surface in which the opening area of the passage hole is large, and a second surface in which the opening area of the passage hole is smaller than the first surface, In at least a part of the direction from the first surface to the second surface, the opening area of the passage hole is formed so as to gradually increase. And it forms so that the 1st surface side may become the upstream of the direction through which the mixture before a dispersion process flows. Furthermore, “the passage hole is formed in an orifice shape” means the following. The flow path in which the passage hole is formed has a first surface in which the opening area of the passage hole is large, and a second surface in which the opening area of the passage hole is smaller than the first surface, In at least a part of the direction from the first surface to the second surface, the opening area of the passage hole is formed so as to gradually increase. And it forms so that the 2nd surface side may become an upstream of the direction in which the mixture before a dispersion process flows.

  Various configurations described so far that are preferable in the first embodiment are also preferable in the second to fifth embodiments described below unless otherwise specified.

  Here, a second embodiment of the wet disperser of the present invention will be described. A second embodiment of the wet disperser of the present invention is a wet disperser 1b as shown in FIG. FIG. 2 is a partially enlarged view of a vertical section of the wet disperser schematically showing a second embodiment of the wet disperser of the present invention, and is a view seen through a part of the flow path. In FIG. 2, the same components as those of the wet disperser of the first embodiment are denoted by the same reference numerals, and the description thereof may be omitted.

  As shown in FIG. 2, the wet disperser 1 b of the second embodiment is configured such that the gap u of the dispersion-portion flow path 15 b excluding the speed change zone 7 b gradually decreases in the flow direction F of the mixture.

  Here, the speed change zone refers to a zone including a portion where the gap in the portion where the flow path in the dispersion portion is the narrowest is 100 μm or less. In FIG. 2, the area surrounded by the broken line is the speed change area 7b. In the speed change zone 7b, the flow path 15b in the dispersion portion is the narrowest from the portion where the flow velocity of the mixture before dispersion treatment increases in the flow passage 15b in the dispersion portion before flowing into the speed change zone 7b. In comparison with the flow rate of the pre-dispersion mixture in the portion that is, it includes up to the portion where the flow rate of the pre-dispersion mixture decreases.

  Here, a third embodiment of the wet disperser of the present invention will be described. 3rd embodiment of the wet disperser of this invention is the wet disperser 1c as shown to FIG. 3A-FIG. 3C. FIG. 3A is a vertical sectional view of a wet disperser schematically showing a third embodiment of the wet disperser of the present invention, and is a view seen through a part of a flow path. FIG. 3B is a plan view of FIG. 3A viewed from the direction of the arrow X, and is a view seen through a part of the flow path. FIG. 3C is an enlarged view of a region β surrounded by a broken line in FIG. 3A.

  The dispersion part 11c in the wet disperser 1c of the third embodiment includes a plurality of speed change zones 7c in the direction F in which the mixture flows. The speed change zone 7c is not particularly limited as long as the gap in the portion of the speed change zone 7c where the flow path 15c in the dispersion portion is the narrowest is 100 μm or less. For example, as shown in FIG. 3A, the speed change zone 7c may have a convex portion P, and the convex portion P may narrow the gap of the dispersion portion inner flow path 15c. The convex portions P in the plurality of speed change areas 7c may have different cross-sectional shapes (including similar shapes) in the A-A ′ cross section, or all may have the same cross-sectional shape.

  As shown in FIGS. 3A to 3C, the in-dispersion flow path 15 c in the wet disperser 1 c of the third embodiment includes a plurality of speed change zones 7 c in the direction F of the mixture flow. If comprised in this way, a complicated flow field will be given in multiple times with respect to the mixture before a dispersion process, and the fine particle before a dispersion process can be disperse | distributed more highly. In FIG. 3B, the mixture flows from the periphery 16 of the dispersion part toward the geometric center of gravity O of the passage hole, but there is no limitation on the direction F in which the mixture flows. For example, the mixture may be configured to flow in the direction opposite to the direction of arrow F shown in FIG. 3B.

  Here, a fourth embodiment of the wet disperser of the present invention will be described. The fourth embodiment of the wet disperser of the present invention is a wet disperser 1d as shown in FIG. FIG. 4 is a partially enlarged view of a vertical sectional view of the wet disperser schematically showing the fourth embodiment of the wet disperser of the present invention, and is a view seen through a part of the flow path.

  The dispersion part in the wet disperser 1d of the fourth embodiment includes a plurality of shift zones 7d in the direction F in which the mixture flows. The plurality of speed change zones 7d are not particularly limited as long as the gaps in the portions where the flow path 15d in the dispersion portion in the speed change zone 7d is the narrowest are each 100 μm or less. For example, in the wet disperser 1 d shown in FIG. 4, each shift area 7 d has a protrusion P individually. This wet disperser 1d is configured such that the mixture flows from the right side to the left side of the sheet of FIG. 4 (the direction in which the mixture flows F), and the protrusions P in the respective speed change zones 7d are in the direction in which the mixture flows. Arranged along F. Moreover, in the wet disperser 1d shown in FIG. 4, the unevenness | corrugation is provided in the inner surface facing the convex part P in the flow path 15d in dispersion | distribution part. In FIG. 4, the projections and depressions provided on the inner surface facing the projections P are arranged in a complementary positional relationship with respect to the projections P arranged continuously. However, the position of the unevenness is not limited to this. For example, you may arrange | position so that the vertex of the convex part P and the convex vertex in an unevenness | corrugation may oppose. The protrusions P in the plurality of shift zones 7d on the protrusions P may have different cross-sectional shapes (including similar shapes) in the AA ′ cross section, or all may have the same cross-sectional shape. Good. Further, the unevenness provided on the surface facing the convex part P may be a non-complementary shape with respect to the convex part P in which the cross-sectional shape in the AA ′ cross section is continuously arranged, The shape may be complementary or substantially complementary. Moreover, there is no restriction | limiting in particular about the number of the speed change area 7d.

  As shown in FIG. 4, the in-dispersion flow path 15 d in the wet disperser 1 d of the fourth embodiment includes a plurality of shift zones 7 d in the direction F in which the mixture flows. If comprised in this way, a complicated flow field will be given in multiple times with respect to the mixture before a dispersion process, and the fine particle before a dispersion process can be disperse | distributed more highly. Further, the unevenness provided in the flow path 15d in the dispersion part facing the convex part P gives a more complicated flow field to the mixture before the dispersion treatment.

  Here, a fifth embodiment of the wet disperser of the present invention will be described. The fifth embodiment of the wet disperser of the present invention is a wet disperser 1e as shown in FIG. It is the elements on larger scale of the vertical cross section of the wet disperser which show typically 5th embodiment of the wet disperser of this invention, and is the figure which saw through a part of flow path. In FIG. 5, the same components as those of the wet disperser of the first embodiment are denoted by the same reference numerals, and the description thereof may be omitted.

  As shown in FIG. 5, the wet disperser 1e of the fifth embodiment is configured as follows. Another speed change zone in which the gap t of the portion where the flow path 15e in the dispersion portion is narrowest in the first speed change zone 7e on the upstream side in the flow direction F of the mixture is provided downstream of the one speed change zone 7e. 7e is wider than the gap t at the narrowest part. Here, when a plurality of shift zones 7e are provided, when the pre-dispersion mixture passes, a greater pressure is applied to the upstream shift zone 7e than to the downstream shift zone 7e. Therefore, by configuring as described above, it is possible to reduce damage, wear, and the like of the plurality of shift zones 7e.

  Here, a sixth embodiment of the wet disperser of the present invention will be described. 6th Embodiment of the wet disperser of this invention is the wet disperser 1f as shown to FIG. 6A-FIG. 6D. FIG. 6A is a vertical sectional view of a wet disperser schematically showing a sixth embodiment of the wet disperser of the present invention, and is a view seen through a part of a flow path. 6B is a plan view of FIG. 6A as seen from the direction of arrow X, and is a view seen through an odd-numbered shift area unit. 6C is a plan view of FIG. 6A viewed from the direction of the arrow X, and is a view seen through the even-numbered shift area unit. FIG. 6D is an enlarged view of a region γ surrounded by a broken line in FIG. 6A. 6A to 6D, the same components as those of the wet disperser of the first embodiment are denoted by the same reference numerals, and the description thereof may be omitted.

  As shown in FIGS. 6A to 6D, the shift zone 7 f in the wet disperser 1 f of the sixth embodiment includes a plurality of shift zone units 17 including at least one shift zone 7 f in the direction F in which the mixture flows. Each of the transmission area units 17 is provided with a transmission area unit passage hole 19 through which the mixture passes between the plurality of transmission area units 17. The plurality of shift area units 17 are arranged in a stacked state so that the directions F in which the mixture flows are parallel to each other. By configuring in this manner, the apparatus can be compactly integrated even when the in-dispersion channel 15f is long. In FIG. 6B and FIG. 6C, eight shift zone unit passage holes 19 are illustrated by solid circles and broken circles, respectively. In FIG. 6D, two shift area unit passage holes 19 are shown below the passage hole 9f in the center of the drawing, and three shift area unit passage holes 19 are shown on the left and right sides of the drawing. Further, the mixture that has passed through the dispersing portion 11f is discharged from the transmission area unit passage hole 19 provided in the transmission area unit 17 that is located on the most downstream side.

  The plurality of transmission area units in the wet disperser of the sixth embodiment are preferably provided on a plane parallel to the plane on which the passage hole is formed. By comprising in this way, the mixture before a dispersion | distribution process can be uniformly flowed in with respect to a some shift area unit (shift area).

  As shown in FIGS. 6B and 6C, the odd-numbered (first, third,...) Shift area unit passage hole 19 is preferably provided on the outer periphery of the shift area unit 17. The transmission zone unit passage holes 19 of the even-numbered stages (second stage, fourth stage,...) Are provided on a straight line that is perpendicular to the geometric center of gravity O of the opening of the passage hole 9f. It is preferable. With this configuration, the mixture before dispersion sufficiently passes through the speed change zone unit 17 (speed change zone 7f) (does not cause a short pass).

  The speed change zone 7f is not particularly limited as long as the gap in the portion where the flow path in the dispersion portion in the speed change zone 7f is the narrowest is 100 μm or less. For example, as shown in FIG. 6A, the speed change zone 7 f may have a convex portion P, and the convex portion P may narrow the gap of the dispersion portion internal flow path 15 f. The convex portions P in the plurality of speed change zones 7f may have different cross-sectional shapes (including similar shapes) in the A-A ′ cross section, or all may have the same cross-sectional shape.

  It is also preferable that the wet disperser of the sixth embodiment has a plurality of speed change zones, and in the speed change zone, the gap in the portion where the flow path in the dispersion portion is the narrowest gradually decreases in the direction F in which the mixture flows.

(Other configurations)
FIG. 7 is a vertical sectional view of the wet disperser schematically showing a case where the wet disperser of the present invention further includes a vibrator, and is a view seen through a part of the flow path. In FIG. 7, the same components as those of the wet disperser of the first embodiment are denoted by the same reference numerals, and the description thereof may be omitted. As shown in FIG. 7, the wet disperser of the present invention may further include a vibrating body 21 that vibrates the dispersing portion 11. The vibrating body 21 may vibrate the dispersion portion 11 so as to continuously change the gap t in the portion where the flow path 15 in the dispersion portion is the narrowest in the speed change zone 7. By comprising in this way, dispersion | distribution of the mixture before a dispersion process can further be accelerated | stimulated. The vibrating body 21 shown in FIG. 7 includes a rubber plate 23 that is an elastic body, a vibrator (piston) 25 provided so as to sandwich the first surface R1 and the second surface R2 of the rubber plate 23, and a vibrator. 27 is a vibrating body 21. The vibrating body 21 vibrates the dispersing portion 11 so as to continuously change the gap t in the portion where the flow path 15 in the dispersing portion is the narrowest. It is not limited to examples.

  When the wet disperser of the present invention has a vibrating body that vibrates the dispersing portion, the amplitude of the vibrating body in a direction perpendicular to the opening of the passing hole is preferably 10 μm to 10 mm. It is preferable that the frequency of the vibrating body in a direction perpendicular to the opening is 10 to 10,000 Hz. The wet disperser of the present invention may have a plurality of vibrators, the amplitude in a direction perpendicular to the openings of the passage holes of the plurality of vibrators, and the openings of the passage holes of the plurality of vibrators. The frequencies in the direction perpendicular to may be different from each other.

  The wet disperser of the present invention preferably has an ultrasonic wave generating means on the downstream side of the passage hole. By providing such ultrasonic wave generation means, it is possible to prevent reaggregation of the fine particles after the dispersion treatment in the mixture after the dispersion treatment. Fine particles after dispersion treatment tend to re-aggregate in the dispersion medium. However, when ultrasonic vibration is applied to the mixture after dispersion treatment by such ultrasonic wave generation means, re-aggregation of fine particles after dispersion treatment is suppressed. be able to. Furthermore, even when fine particles after dispersion treatment that are not sufficiently dispersed exist in the mixture after dispersion treatment, the fine particles after dispersion treatment that are not sufficiently dispersed can be sufficiently dispersed by the ultrasonic wave generating means. Ultrasonic wave generation means is not particularly limited, and known ultrasonic wave generation means can be used, but an ultrasonic wave transmission unit, an ultrasonic wave generation horn disposed in a flow path through which the mixture after dispersion treatment flows, It is preferable to provide. Moreover, it is preferable that the ultrasonic transmission part can control the generated ultrasonic wave, and the frequency of the ultrasonic wave is preferably 20 kHz to 10 MHz. Further, in order to sufficiently vibrate the mixture after the dispersion treatment by the ultrasonic wave generation means, the area where the ultrasonic horn of the flow path is disposed is provided with a space portion having a wide diameter flow path. It is preferable.

  FIG. 8 is an explanatory diagram schematically showing a dispersion process using the wet disperser of the present invention. As shown in FIG. 8, in the wet disperser 1 of the present invention, a storage tank 29 for storing the pre-dispersion mixture may be provided before the inlet 3. In addition, the storage tank 29 and the wet disperser 1 may be connected by a liquid feeding pipe 31, and a liquid feeding pump 33 that supplies the mixture before dispersion treatment may be connected to the inlet 3 side. Further, the storage tank 29 may be provided with a stirrer 44 for stirring the mixture before dispersion treatment. Further, a recovery tank 37 for recovering the mixture after the dispersion treatment is provided at the subsequent stage of the outlet 5, and the recovery tank 37 and the wet disperser 1 are connected by the liquid feeding pipe 31 and sucked toward the outlet 5. A pump 39 or the like may be connected.

  In the wet disperser of the present invention, for example, the mixture containing at least the fine particles and the dispersion medium can be passed through the wet disperser a plurality of times depending on the aggregation state of the fine particles. Depending on the fine particles before dispersion treatment and the physical properties of the dispersion medium, the mixture after dispersion treatment passed through the wet disperser of the present invention once (one pass) is further passed through the wet disperser of the present invention several times ( 2 pass, 3 pass... N pass n: positive integer), the degree of control of the particle size of the fine particles and the degree of control of the particle size distribution can be increased. Further, the wet disperser of the present invention can obtain the same effect by connecting a plurality of wet dispersers in series. That is, the mixture passes through each wet disperser connected in series with the first wet disperser, the second wet disperser, and the third wet disperser. A storage tank or the like may be appropriately provided between the wet dispersers connected in series. In addition, the wet disperser of the present invention can be designed in various ways such as processing a large amount of mixture by arranging a plurality of wet dispersers in parallel.

(blend)
In the wet disperser of the present invention, the “mixture” before the dispersion treatment mainly comprises primary particles and aggregates (including the consolidated particles weakly consolidated in the aggregates). It is configured to include at least one kind of fine particles selected from the group and a dispersion medium. That is, the “mixture” includes (1) at least a primary particle and a dispersion medium, (2) at least an aggregate and a dispersion medium, and (3) a primary particle and an aggregate, and a dispersion. Including at least a medium. Therefore, in this specification, “at least one kind of fine particles selected from the group consisting of primary particles and aggregates” means (1 ′) primary particles, (2 ′) aggregates, (3 ′) This applies to either primary particles or aggregates.

  In addition to the fine particles and the dispersion medium, the “mixture” may contain known additives used in the dispersion treatment. For example, the fine particles after the dispersion treatment of the surfactant, the charge control agent, etc. The dispersion stabilizer may be included.

  Further, the ratio (volume ratio, mass ratio, etc.) of the fine particles dispersed using the wet disperser of the present invention is not particularly limited, and the particle diameter of the fine particles before dispersion treatment, It is appropriately determined according to the particle diameter and particle size distribution of the fine particles after dispersion treatment to be obtained and the use of the fine particles after dispersion treatment.

(Dispersoid)
There is no restriction | limiting in particular in the material of the microparticles | fine-particles before a dispersion process contained in a mixture. A known dispersoid used for the dispersion treatment may be used as the fine particles before the dispersion treatment. For example, silica, zirconia, alumina, titania, zinc oxide, or the like can be used. Further, the material of the fine particles does not change between the fine particles before the dispersion treatment and the fine particles after the dispersion treatment by the wet disperser of the present invention. That is, the fine particles before the dispersion treatment and the fine particles after the dispersion treatment differ only in the median diameter, fiber diameter, and fiber length, and the elements constituting the fine particles do not chemically react.

(Dispersion medium)
There is no restriction | limiting in particular in the dispersion medium contained in a mixture. A known dispersion medium used for the dispersion treatment may also be used. For example, water, ethyl alcohol, methyl alcohol, hexane, benzene, toluene, methylene chloride, or the like can be used.

  The mixture can be obtained by mixing fine particles which are dispersoids as described above and a dispersion medium at a predetermined mixing ratio. To the mixture, a dispersion stabilizer of fine particles after dispersion treatment such as a surfactant and a charge control agent may be added. The mixture containing at least the pre-dispersion fine particles and the dispersion medium thus obtained is fed to the wet disperser of the present invention and subjected to dispersion treatment.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

Example 1
While using the wet disperser 1c as shown in FIG. 3A to FIG. 3C, a sample (mixture before dispersion treatment) in which aggregated particles (amorphous fumed silica) are mixed in advance in a dispersion medium is used before dispersion treatment. An experiment was conducted to confirm the dispersion state of the fine particles after the dispersion treatment in the dispersion medium.

  Specifically, as shown in FIG. 8, a liquid feed pipe 31 is provided so that the pre-dispersion mixture can be fed from the storage tank 29 storing the sample (mixture before dispersion treatment) to the wet disperser 1. And a liquid feed pump 33 was disposed between the storage tank 29 and the wet disperser 1.

  A diaphragm pump (manufactured by Prominent, model number: BT4b1602S) was used as the liquid feed pump. The frequency of the liquid feed pump was set to 3.1 Hz, and the stroke length was set to 100%. The liquid feeding amount of the mixture before dispersion treatment was 27.62 to 34.72 g / min, and the average value was 32.91 g / min. Moreover, the liquid feeding pressure of the liquid feeding pump was 1.0 to 2.0 MPa, and the average value thereof was 1.5 to 1.8 MPa. Further, a liquid feeding tube having a diameter of 4 mm was used.

  As a wet disperser, dispersion model 1 manufactured by Okawara Chemical Industries Co., Ltd. was used. The wet disperser includes five shift zones in the flow path in the direction in which the mixture before dispersion treatment flows, and a convex portion P is provided in the shift zone. In the speed change zone, the gap t in the portion where the flow path in the dispersion portion is the narrowest is 5 μm.

  For the sample, REOLOSIL QS-102 manufactured by Tokuyama Corporation was used as aggregated particles before the dispersion treatment, and ion-exchanged water was used as the dispersion medium. The sample is prepared by suspending 1.57075 g of Leoroseal in 300 ml of ion-exchanged water so that 0.5% by mass of Leoroseal is contained in the ion-exchanged water, and stirring with a stirrer for 10 minutes at a rotation speed of 230 rpm. Was done. The stirring blade of the stirrer was rotated so as not to be in direct contact with the stirring tank. Next, what was filtered using a 100-micrometer sieve was made into the mixture before a dispersion process.

About the particle size and particle size distribution (particle size distribution) of the fine particles dispersed in the dispersion medium for the mixture before the dispersion treatment by the wet disperser configured as described above and the mixture after the dispersion treatment are multi-angled. It measured with the dynamic light-scattering apparatus (Otsuka Electronics Co., Ltd. make, model number: MCLS-1000). As physical properties of ion-exchanged water as a dispersion medium, the refractive index was 1.3313, the viscosity was 0.8847 (MPa · s), and the temperature was 25.0 (° C.). The measurement was performed twice for 180 seconds. The probe used was a dilute system, and the analysis method was the cumulant method. In addition, about the microparticles | fine-particles after carrying out the dispersion process, the microparticles | fine-particles after 1 pass which passed the wet disperser once were evaluated. The results are shown in FIG. In addition, in FIG. 9, the result of Example 1 was shown as the continuous line. Further, from the particle size distribution of the measured particles (particle size distribution), and the median diameter, the value _{D 90} of 90% cumulative diameter is a value obtained by dividing the value _{D 10} of 10% accumulated _diameter, and D 90 _{/ D 10} Asked. The smaller the median diameter and the smaller the value of D ₉₀ / D ₁₀ , the higher the degree of dispersion of the fine particles after dispersion treatment. The results are shown in Table 1.

(Comparative Example 1)
The same measurement and evaluation as in Example 1 were performed for a mixture (sample) before dispersion treatment that was not subjected to dispersion treatment with a wet disperser. The results are shown in FIG. In addition, in FIG. 9, the result of the comparative example 1 was shown with the short broken line.

(Comparative Example 2)
Measurement and evaluation were performed in the same manner as in Example 1 except that the mixture (sample) before dispersion treatment was subjected to dispersion treatment using an ultrasonic homogenizer (manufactured by Qsonica, model number: Astrason S4000). Dispersion treatment with an ultrasonic homogenizer was performed by irradiating ultrasonic waves with an amplitude of 15 μm once each time the mass same as the mass passing through the wet disperser 1 passes through the ultrasonic homogenizer with one vibration of the diaphragm pump. . The results are shown in FIG. In addition, in FIG. 9, the result of the comparative example 2 was shown with the long broken line.

(result)
The median diameter of the fine particles after dispersion treated by the wet disperser of the present invention is 0.58 times the median diameter of the fine particles before dispersion treatment, and the dispersion treatment dispersed by a conventional ultrasonic homogenizer It was 0.72 times the median diameter of the post-fine particles. In addition, the value of D ₉₀ / D ₁₀ of the fine particles after the dispersion treatment dispersed by the wet disperser of the present invention is 2.1 times higher than the value of D ₉₀ / D ₁₀ of the fine particles before the dispersion treatment. It was 1.2 times higher than the D ₉₀ / D ₁₀ value of the dispersed fine particles dispersed by the sonic homogenizer. For this reason, the degree of dispersion of the dispersed fine particles dispersed by the wet disperser of the present invention was better than the dispersed fine particles not dispersed by the wet disperser of the present invention.

(Discussion)
From the above results, it was found that the wet disperser of the present invention can disperse the pre-dispersion fine particles as post-dispersion fine particles having a median diameter of 1 to 500 nm in a dispersion medium with a high degree of dispersion.

  INDUSTRIAL APPLICABILITY The present invention can be used for dispersing various fine particles as a wet disperser that can hardly disperse (contaminate foreign matter), can uniformly disperse fine particles in a short time, and can be operated with reduced energy and space.

1, 1b, 1c, 1d, 1e, 1f: Wet disperser, 3: Inlet, 5: Outlet, 7, 7b, 7c, 7d, 7e, 7f: Shift zone, 9, 9c, 9e, 9f: Pass Hole, 11, 11c, 11f: Dispersion part, 12: Periphery (periphery of D1), 13: Flow path, 14: Perimeter (periphery of D2), 15, 15b, 15c, 15d, 15e, 15f: Flow path in dispersion part 16: Around the dispersal part, 17: Shift area unit, 19: Shift area unit passage hole, 21: Vibrating body, 23: Rubber plate, R1: First surface of the rubber plate, R2: Second surface of the rubber plate 25: Vibrator (piston), 27: Vibrator, 29: Storage tank, 31: Liquid feed pipe, 33: Liquid feed pump, 37: Collection tank, 39: Suction pump, 44: Stirrer, t: Within the speed change zone Between the narrowest part of the flow path in the dispersion part , U: spacing between the flow paths in the dispersion part, D1: a plane parallel to the flow direction of the mixture, and all of its peripheral edges are defined by the speed change zone, D2: a mixture formed on the outer peripheral side of the speed change zone F: the flow direction of the mixture, O: geometric center of gravity of the passage hole, T: corner, M: perpendicular foot, L: from the periphery of the dispersed portion Length to passage hole, P: convex part.

Claims (11)

A wet disperser for dispersing the fine particles in a mixture containing at least one fine particle selected from the group consisting of primary particles and aggregates and a dispersion medium;
An inlet and an outlet serving as a flow path for the mixture, and a flow path extending from the inlet to the outlet;
The flow path has a dispersion part provided in the middle of the flow path,
The dispersion part has a flow channel in the dispersion part that forms a part of the flow path,
The flow path in the dispersion part includes a speed change zone that changes a flow rate of the mixture by narrowing a gap of the flow path in the dispersion part in a direction in which the mixture in the flow path in the dispersion part flows.
The wet disperser in which the gap in the portion where the flow path in the dispersion portion in the speed change zone is the narrowest is 100 μm or less.   The wet disperser according to claim 1, wherein the primary particles include a particulate material or a fibrous material.   The wet disperser according to claim 1, wherein the fine particles are dispersed as nano fine particles having a median diameter of 1 to 500 nm in the mixture after the dispersion treatment.   The fine particles are dispersed in the mixture after dispersion treatment as fine particles after dispersion treatment with a median diameter of 500 nm to 10 μm, or the fine particles are dispersed in the mixture after dispersion treatment as nanofibers having a fiber diameter of 1 to 100 nm. The wet disperser according to claim 1 or 2.   The dispersion portion is provided with a passage hole on the downstream side of the speed change zone, and the passage hole is provided at a position where the length of the periphery of the dispersion portion and the passage hole are equal. The wet disperser according to any one of claims 1 to 4.   The wet disperser according to any one of claims 1 to 5, wherein a gap of the flow path in the dispersion portion excluding the shift zone is gradually reduced in a direction in which the mixture flows.   The wet disperser according to any one of claims 1 to 6, wherein the flow path in the dispersion section includes a plurality of the speed change zones in a direction in which the mixture flows.   The gap in the part where the flow path in the dispersion part is narrowest in the one shift area on the upstream side in the flow direction of the mixture is in the other shift area provided on the downstream side of the one shift area. The wet disperser according to claim 7, wherein the flow path in the dispersion section is wider than a gap in a narrowest portion.   The dispersion portion is provided with a passage hole upstream of the speed change zone, and the passage hole is provided at a position where the length of the periphery of the dispersion portion and the passage hole are equal. The wet disperser according to any one of claims 1 to 4. The dispersion unit has a plurality of shift area units including at least one shift area in a direction in which the mixture flows,
Each of the plurality of transmission zone units is provided with a transmission zone unit passage hole through which the mixture passes between the transmission zone units.
The wet disperser according to claim 9, wherein the plurality of speed change area units are arranged in a stacked state so that directions in which the mixture flows are parallel to each other.   The wet disperser according to claim 10, wherein the plurality of shift area units are provided on a surface parallel to a surface on which the passage hole is formed.