JP4186637B2 - Particle manufacturing method and microchannel structure therefor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is a particle production method suitably used for producing fine droplets and gel particles used for sorting, separation column fillers, etc., and also produces particles such as fine droplets. The present invention relates to a microchannel structure for the purpose.
[0002]
[Prior art]
In recent years, by using a microchannel structure having a microchannel having a length of about several centimeters on a glass substrate or a resin substrate of several centimeters square and having a width and a depth of sub μm to several hundred μm, Research that produces fine particles by feeding liquids is attracting attention. (For example, see Non-Patent Documents 1 and 2)
Regarding the particle generation technique in the microchannel, as shown in FIG. 1, the continuous phase inlet 2, the continuous phase inlet channel 3, the dispersed phase inlet 4, and the dispersed phase inlet flow on the microchannel substrate 1. It is a T-shaped structure having a path 5, a discharge flow path 7, and a discharge port 8, and a merging portion 6 exists at a portion where the introduced continuous phase and the dispersed phase merge. The depth of each channel is 100 μm, the introduction channel width for introducing the dispersed phase is 100 μm, and the introduction channel width for introducing the continuous phase is 300 to 500 μm. When liquid feeding is performed by controlling the flow rate of the continuous phase, extremely uniform microparticles can be generated at a point where the dispersed phase and the continuous phase merge through the flow path (merging portion). It is also possible to control the generated particle size by controlling the flow rates of the dispersed phase and the continuous phase. However, this method has a problem that, as the liquid feeding speed of the dispersed phase is increased, stable particle generation cannot be obtained, and eventually a laminar flow becomes impossible. Further, since the flow path forming material is made of glass such as blue plate, quartz, Pyrex (registered trademark) or Si, when the dispersed phase is a hydrophobic liquid and the continuous phase is a hydrophilic liquid, Since the formation is more stable than particle generation, it has been substantially difficult to generate particles.
[0003]
In order to solve this problem and to generate fine particles, attempts have been made to solve by surface treatment, but over a long period of time, particle generation could not be performed, and further improvements were required. .
[Non-Patent Document 1]
Takashi Nishisako et al., “Microdroplet production in microchannels”, 4th Chemistry and Microsystems Research Meeting, 2001, 59 pages
[Non-Patent Document 2]
TAKASI NISISAKO et al., “DROPLET FORMATION IN A MICROCHANNEL ON PMMA PLATE”, Micro Total Analysis System 2001, pp. 137-138
[0004]
[Problems to be solved by the invention]
As described above, the conventional technology for generating particles such as droplets in a microchannel enables generation of extremely uniform particles at the junction of a continuous phase and a dispersed phase in a T-shaped microchannel. As the flow velocity increased, the particleization phenomenon became unstable and eventually became laminar. In addition, there is a problem of the affinity between the dispersed phase liquid and the wall surface of the fine channel, which is a problem when producing various liquid particles, and further improvement has been demanded for industrial mass production.
[0005]
The present invention has been made in view of the above-described problems, and enables particle generation in a microchannel, and also enables particle generation in a combination of various dispersed phases and continuous phases. An object of the present invention is to provide a particle manufacturing method that can be applied to mass production and a microchannel structure therefor.
[0006]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention continuously introduces a dispersed phase and two or more continuous phases into a structure having a microchannel, and a portion where the dispersed phase and the continuous phase merge (hereinafter referred to as “merge”). In this case, the dispersed phase is sheared by bringing the dispersed phase into contact with the continuous phase so that the continuous phase is sandwiched between the dispersed phase. In order to generate a dispersed phase, an inlet for introducing a dispersed phase and an introduction channel communicating therewith, two or more inlets for introducing a continuous phase, an introduction channel communicating therewith, and two or more dispersed phases It has a discharge flow path consisting of a micro flow path for discharging particles generated by the continuous phase and a discharge port communicating with the discharge flow path, and has an aspect ratio (depth / width ratio of the flow path) of the cross section of the discharge flow path. Also found that it should be 0.30 or more, It is possible to solve the problems caused by technology, it has led to the completion of the finally the present invention.
[0007]
That is, in the present invention, the dispersed phase and two or more continuous phases are continuously introduced into a structure having a microchannel, and the dispersed phase and the continuous phase are brought into contact with each other to shear the dispersed phase to form fine particles. And a structure for achieving this, an introduction port for introducing a dispersed phase and an introduction channel communicating therewith, an introduction port for introducing a continuous phase, and the same A microchannel structure comprising an introductory channel that communicates, a discharge channel composed of a microchannel for discharging particles generated by a dispersed phase and two or more continuous phases, and a discharge port communicating therewith. The discharge channel cross-sectional aspect ratio (the channel depth / width ratio) is 0.30 or more.
[0008]
In the present specification, “particles” not only mean liquid droplets, that is, droplets, but also may mean solidified ones.
[0009]
Hereinafter, the present invention will be described in detail.
<Particle production method>
As described above, in the particle production method of the present invention, the dispersed phase and the continuous phase are brought into contact with each other while the dispersed phase and two or more continuous phases are continuously introduced into the structure having a microchannel. This is a method of making fine particles by shearing.
[0010]
The dispersed phase used in the present invention is a liquid material for producing particles with a microchannel structure, for example, a monomer for polymerization such as styrene, a crosslinking agent such as divinylbenzene, a gel such as a polymerization initiator, etc. It refers to a medium in which raw materials for production are dissolved in a suitable solvent. Here, as the dispersed phase, the purpose of the present invention is to generate fine particles efficiently, and if it is possible to achieve this purpose, the flow path in the fine flow path structure can be fed. The component is not particularly limited as long as particles can be further formed. Moreover, it may be a slurry in which a solid phase is partially mixed in the dispersed phase.
[0011]
The continuous phase used in the present invention is a liquid material used for generating particles from a dispersed phase by a microchannel structure, and for example, a dispersant for gel production such as polyvinyl alcohol is dissolved in an appropriate solvent. Refers to the medium. Here, the continuous phase is not particularly limited as long as it can feed the flow path in the micro flow path structure, as in the case of the dispersed phase, and the components are not particularly limited as long as particles can be formed. If two or more of the continuous phases have the same composition, the composition of the medium around the particles produced by the dispersed phase can be made uniform or controlled, and the produced particles are removed, treated by light irradiation or heating. It is easy to perform and is preferable. Further, it may be a slurry in which a solid substance is partially mixed in the continuous phase.
[0012]
Furthermore, in order to generate particles, the dispersed phase and the continuous phase must be substantially not intermingled or compatible, for example, when the aqueous phase is used as the dispersed phase, An organic phase such as butyl acetate that is substantially insoluble in water will be used. Moreover, the reverse is true when an aqueous phase is used as the continuous phase.
[0013]
In the present invention, these dispersed phase and continuous phase are continuously introduced into the microchannel structure described below, and the dispersed phase and the continuous phase are brought into contact at the joining portion where both are joined to shear the dispersed phase. The particle diameter of the generated particles is controlled by changing the angle at which the introduction flow path for introducing the dispersed phase and the introduction flow path for introducing the continuous phase intersect. Is possible. This is easier to control and more suitable for industrial mass production in the production of particles using the conventional structure than in the case where the introduction speed of the dispersed phase and the continuous phase is changed. Furthermore, by making the introduction speed of the dispersed phase and the continuous phase to be introduced into the microchannel structure substantially the same, industrial mass production in terms of particle size control of the generated particles and simplification of manufacturing equipment. It can fully cope with.
<Microchannel structure>
The fine channel structure of the present invention is a structure for producing the above-described particles, and is an inlet for introducing a dispersed phase, an introduction channel communicating with the inlet, and a continuous phase. An inlet port and an inlet channel communicating therewith, a discharge channel consisting of a minute channel for discharging particles produced by a dispersed phase and two or more continuous phases, and a outlet port communicating therewith, It has a structure in which the aspect ratio of the road cross section (ratio of the depth / width of the flow path) is 0.30 or more.
[0014]
Here, the introduction port for introducing the dispersed phase means an opening for introducing the dispersed phase, and a mechanism for continuously introducing the dispersed phase by providing an appropriate attachment at the introduction port. Similarly, the introduction port for introducing the continuous phase also means an opening for introducing the continuous phase, and further, as a mechanism for continuously introducing the continuous phase with an appropriate attachment at the introduction port. Good.
[0015]
The introduction flow path for introducing the dispersed phase communicates with the introduction port, and the dispersed phase is introduced and fed along the introduction flow path. The shape of the introduction channel has an influence on controlling the shape and particle diameter of the particles, but the width is formed to be several hundreds μm or less. Similarly, the introduction channel for introducing the continuous phase is the same as the introduction port. The continuous phase is introduced, and the solution is fed along the introduction channel. The shape of the introduction channel affects the control of the particle shape and particle diameter, but the width may be several hundred μm or less. Moreover, the flow path of each continuous phase and the dispersed phase should just be a shape which can introduce | transduce a continuous phase on both sides of a dispersed phase, and cross | intersects toward one point of the flow path of a dispersed phase.
[0016]
The discharge channel communicates with the above three introduction channels and the discharge port, and after the dispersed phase and the continuous phase merge, the liquid is fed along the discharge channel and discharged from the discharge port. The shape of the discharge channel is not particularly limited, but the width may be several hundreds μm or less, and it may be Y-shaped including the introduction channel. The discharge port means an opening for discharging the generated particles, and may be a mechanism for continuously discharging the phase including the generated particles with an appropriate attachment provided to the discharge port.
[0017]
Note that these channels are sometimes referred to as minute channels in this specification.
[0018]
Furthermore, in the microchannel structure of the present invention, the introduction channel for introducing the dispersed phase and two or more introduction channels for introducing the continuous phase intersect at an arbitrary angle, and these three or more It is preferable that the introduction channel has a structure connected to the discharge channel at an arbitrary angle. By making the angle at which these three or more introduction flow passages intersect at an arbitrary angle, the particles generated at the merging portion are controlled to a desired particle diameter so that particles are generated near the merging portion. Can be controlled. The setting of the crossing angle may be appropriately determined according to the particle size of the target particle and the flow rate at the time of generation.
[0019]
As the cross-sectional shapes of the introduction channel and the discharge channel, the aspect ratio of the channel cross section is preferably 0.30 or more, and more preferably 0.30 or more and less than 3.0. If the aspect ratio is within this range, uniform particles can be generated at the junction. If the aspect ratio deviates from this range and is less than 0.30, it may be difficult to generate uniform particles. However, there is no limitation as long as the generated particle diameter is equal to or less than the channel depth.
[0020]
Further, when the width and depth of the introduction flow path for introducing the dispersed phase and the introduction flow path for introducing the continuous phase are equal, in addition to the above effects, the design of the micro flow path structure is facilitated, Moreover, the control at the time of liquid feeding becomes easier, and it is suitable for industrial mass production.
[0021]
In addition, in the relationship between the width of the introduction flow path and the width of the discharge flow path, if the width of the introduction flow path ≧ the width of the discharge flow path, the liquid feed flow velocity is larger than the width of the introduction flow path = the width of the discharge flow path. Even if it is increased, uniform particles can be generated at the confluence, and the effect of increasing the particle generation rate can be obtained, which is a preferred embodiment.
[0022]
As for the width of the discharge channel, it is preferable that the width of the discharge channel is narrow at a part of the discharge channel from the intersection where the dispersed phase and the continuous phase intersect to the discharge port. In other words, it is possible to partially narrow at the junction between the introduction flow path and the discharge flow path up to the particle discharge port, or to form a flow path constituting wall along the dispersed phase flow path in a convex manner. Even if the liquid flow rate is increased, uniform particle generation can be performed at the confluence portion, and an increase in the liquid feeding pressure can be mitigated, which is a preferred embodiment.
[0023]
The microchannel structure according to the present invention has the above-described structure and performance. However, the microchannel structure has three or more introduction portions and introduction channels for introducing a dispersed phase and a continuous phase, and three or more introduction flows. A confluence portion where the passages intersect, a fine flow passage structure having a discharge flow passage and a discharge port for discharging liquid, a substrate having a fine flow passage formed on at least one surface, and a fine flow passage are formed. A cover body in which at least four or more small holes for communicating the microchannel and the outside of the microchannel structure are arranged at predetermined positions of the microchannel so as to cover the substrate surface is laminated and integrated. It may be. As a result, the fluid can be introduced from the outside of the microchannel structure into the microchannel and discharged again to the outside of the microchannel structure. It is possible to pass through the minute flow path. Fluid feeding is possible by mechanical means such as a micropump.
[0024]
As the material of the substrate and the cover body on which the microchannel is formed, it is desirable that the microchannel can be formed, has excellent chemical resistance, and has an appropriate rigidity. For example, glass, quartz, ceramic, silicon, or metal or resin may be used. The size and shape of the substrate and cover body are not particularly limited, but the thickness is preferably about several mm or less. The small holes arranged in the cover body communicate with the microchannel and the outside of the microchannel structure, and when used as a fluid inlet or outlet, the diameter is preferably, for example, several mm or less. The small holes in the cover body can be processed chemically, mechanically, or by various means such as laser irradiation or ion etching.
[0025]
In the microchannel structure of the present invention, the substrate on which the microchannels are formed and the cover body are laminated and integrated by means such as heat bonding or adhesion using an adhesive such as a photo-curing resin or a thermosetting resin. be able to.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, examples of the present invention will be described, and the embodiments of the invention will be described in more detail. It is needless to say that the present invention is not limited to the following examples and can be arbitrarily changed without departing from the gist of the present invention.
In the embodiment, one micro flow channel is formed on one substrate. However, in the case of mass production industrially, a large number of micro flow channels are formed on a single substrate or a large number of micro flow channels are formed. This is possible by stacking one substrate.
(Example 1)
FIG. 2 shows a microchannel for producing particles in the first embodiment of the present invention. The microchannels are on a Pyrex (registered trademark) glass of 70 mm × 20 mm × 1 t (thickness), and the widths of the continuous phase introduction channel 3, the dispersed phase introduction channel 5, and the discharge channel 7 corresponding to the microchannels. All have a fine channel shape of 140 μm, a depth of 60 μm, and an aspect ratio of the micro channel = 0.43, and the continuous phase introduction channel 3 and the dispersed phase introduction channel 5 intersect at an angle of 22 degrees. One flow path having a shape having a shape was formed. The width and depth of the microchannel depend on the diameter of the droplet particles to be generated, but it is sufficient that the aspect ratio of the microchannel does not deviate from the range of 0.3 or more and less than 3.
[0027]
This micro-channel structure for manufacturing a Y-shaped particle was manufactured as follows according to the manufacturing procedure shown in FIG. A metal film 10 made of gold or the like is formed on one surface of a glass substrate 9 having a thickness of 1 mm and a size of 70 mm × 20 mm so that exposure light described later is not transmitted (FIG. 3 (a) metal film forming step). ), A photoresist 11 was coated on the metal film (FIG. 3B, a photoresist coating step). Further, a photomask 12 having a pattern depicting the shape of the microchannel was placed on the photoresist, and exposure was performed from the photomask for development (FIG. 3 (c) exposure to development process). Next, after etching the metal film 10 with an acid or the like (FIG. 3D, the etching process of the metal film), the resist and glass are etched with hydrofluoric acid or the like (FIG. 3E, the resist and glass etching process), Further, the remaining metal film 10 was dissolved with an acid or the like (FIG. 3 (f) metal film removal step) to obtain a substrate 13 on which microchannels were formed. In the embodiment, the micro flow channel is formed by etching the glass substrate, but the manufacturing method is not limited to this.
[0028]
The diameter of the substrate 13 on which the microchannels are formed has a diameter 0 in advance at a position corresponding to the fluid inlet (continuous phase inlet 2, dispersed phase inlet 4) and fluid outlet 8 of the microchannel. A micro-channel for particle production provided with a micro-channel as shown in FIG. 4 by thermally joining a glass cover body 14 having a thickness of 1 mm and a thickness of 70 mm × 20 mm provided with a small hole of 6 mm using mechanical processing means A structure was made. In the embodiment, the glass substrate is used for the substrate for forming the microchannel and the cover body, but the present invention is not limited to this.
[0029]
Next, the particle manufacturing method of the present invention will be described. As shown in FIG. 5, the liquid is held by the holder 16 or the like so that the liquid can be fed to the droplet generation microchannel structure 15, and the Teflon (registered trademark) tube 18 and the fillet joint 19 are fixed to the holder 16. . The other end of the Teflon (registered trademark) tube 18 is connected to the microsyringes 21, 22, and 23. As a result, liquid can be fed to the micro-channel structure 15 for particle production. Next, a mixed solution of monomer (styrene), divinylbenzene, butyl acetate, and benzoyl peroxide is injected into the microsyringe 23 as a dispersed phase for producing particles, and a 3% aqueous solution of polyvinyl alcohol is added into the microsyringes 21 and 22 as a continuous phase. The solution was injected, and the solution was fed with the microsyringe pump 20. The liquid feeding flow rate is 6 μl / min for both the dispersed phase and the continuous phase. Particle generation is observed at the junction where the dispersed phase and continuous phase of the micro-flow channel structure 15 for particle production intersect in a state where both the liquid feeding flow rates are stable. When the produced particles 23 were observed, they were extremely uniform particles having an average particle diameter of 77 μm as shown in FIG.
(Example 2)
FIG. 4 shows a microchannel for producing particles in the second embodiment of the present invention. The microchannels are on a polyetherimide substrate of 70 mm × 20 mm × 1 t (thickness), and the widths of the continuous phase introduction channel 3, the dispersed phase introduction channel 5, and the discharge channel 7 corresponding to the microchannels are all. 140 μm, depth 60 μm, microchannel shape with microchannel aspect ratio = 0.43, and has a junction where the continuous phase introduction channel 3 and the dispersed phase introduction channel 5 intersect at an angle of 22 degrees One flow path having a different shape was formed. Using the same photomask and method as shown in Example 1 as the production method, a flow path was formed on a 200 mm diameter Pyrex (registered trademark) glass substrate, a Ni thin film was formed, and a thickness of 300 μm was formed by electroplating. A stamper was produced and placed in a mold of a molding machine to produce a polyetherimide resin by an injection molding method. The produced flow path substrate was cut out at 70 mm × 20 mm × 1 t. The width and depth of the microchannel may depend on the particle diameter to be generated, but the microchannel aspect ratio does not have to depart from the range of 0.3 or more and less than 3.
[0030]
As shown in FIG. 5, the microfluidic structure 15 for particle production is held by a holder 16 or the like so that liquid can be fed, and a Teflon (registered trademark) tube 18 and a fillet joint 19 are fixed to the holder 16. The other end of the Teflon (registered trademark) tube 18 is connected to the microsyringes 21, 22, and 23. As a result, liquid can be fed to the micro-channel structure 15 for particle production. Next, a mixed solution of monomer (styrene), divinylbenzene, butyl acetate, and benzoyl peroxide is injected into the microsyringe 23 as a dispersed phase for producing particles, and a 3% aqueous solution of polyvinyl alcohol is added into the microsyringes 21 and 22 as a continuous phase. The solution was injected, and the solution was fed with the microsyringe pump 20. The liquid feeding flow rate is 6 μl / min for both the dispersed phase and the continuous phase. Particle generation is observed at the junction where the dispersed phase and continuous phase of the micro-flow channel structure 15 for particle production intersect in a state where both the liquid feeding flow rates are stable. When the produced particles 23 were observed, they were extremely uniform particles having an average particle diameter of 77 μm as shown in FIG.
(Example 3)
Next, FIG. 11 shows a fine channel for particle production in Example 3. As in Example 1, the microchannels are 70 mm × 20 mm × 1 t (thickness) on glass, and the widths of the continuous phase introduction channel 3, the dispersed phase introduction channel 5, and the discharge channel 7 are all 140 μm in depth. Y-shape with 60 μm, micro-channel aspect ratio = 0.43, and Y-shape with confluence where continuous phase introduction flow path 3 and dispersed phase introduction flow path 5 intersect at an angle of 44 degrees When one channel is formed and the crossing angle between the dispersed phase and the continuous phase is less than 90 degrees as shown in FIG. 11, that is, when the upstream of the channels of the dispersed phase and the continuous phase is on the same side, Each flow path of the continuous phase
Protrusions 24 are provided at the outlet of the continuous phase channel or the outlet of the discharge channel at the intersection of both channels that merge with the dispersed phase channel, the channel width is locally narrowed, and the flow of the continuous phase is temporarily stopped, By changing the direction of flow, the dispersed phase was sheared in the vicinity of the merged part to form particles. The production procedure of the fine channel structure for particle production was produced in the same procedure as in Example 1. Next, in the same manner as in Example 1, the fine channel structure for particle production is held by a holder and fixed and connected to a Teflon (registered trademark) tube, a fillet joint, and a microsyringe pump. A mixed solution of monomer (styrene), divinylbenzene, butyl acetate and benzoyl peroxide was injected into a dispersed phase for generating particles, and a 3% aqueous solution of polyvinyl alcohol was injected into a microsyringe as a continuous phase, and the solution was fed. The liquid feeding flow rate is 6 μl / min for both the dispersed phase and the continuous phase.
[0031]
When the joining portion where the dispersed phase and the continuous phase of the particle generating microchannel structure intersect with each other in a state where both the flow rates are stable is observed, the particle 25 produced in the vicinity of the joining portion as shown in FIG. Was stably produced, and the dispersibility was improved to 5% as compared with Example 1. In Example 3, a protrusion-like structure is provided as a method of narrowing the outlet of the continuous phase or the outlet of the discharge channel. However, the dispersed phase is sheared while squeezing the continuous phase, and the particle generation site is in the vicinity of the junction. As long as the structure has the same effect as described above, the method is not limited to this method, and a method of providing a protrusion in the flow channel or constricting the flow channel may be used.
[0032]
Further, as shown in FIG. 13, the angle at which the introduction flow path for introducing the dispersed phase and the introduction flow path for introducing the continuous phase intersect is 90 degrees or more, that is, the upstream of the flow path of the dispersed phase and the continuous phase is opposite. In the case of being on the side, since the continuous phase is a flow that pushes up the dispersed phase, the combination of the crossing angle and the flow velocity can be adjusted to bring the particle generation location in the flow path closer to the both flow path joining portions.
(Comparative Example 1)
Next, FIG. 9 shows a microchannel for particle production in Comparative Example 1. Similar to the first embodiment, the microchannel has a width of 70 mm × 20 mm × 1 t (thickness) Pyrex (registered trademark) glass, continuous phase introduction channel 3, dispersed phase introduction channel 5, and discharge channel 7. In each case, a Y-shape with 140 μm, a depth of 60 μm, and a microchannel aspect ratio = 0.43 is formed, and a joining portion where the continuous phase introduction channel 3 and the dispersed phase introduction channel 5 intersect at an angle of 44 degrees is formed. One channel having a shape was formed. The production procedure of the fine channel structure for particle production was produced in the same procedure as in Example 1.
[0033]
Next, as shown in FIG. 10, the particle manufacturing microchannel structure is held by a holder, and fixed and connected to a Teflon (registered trademark) tube, a fillet joint, and a microsyringe pump. A mixed solution of monomer (styrene), divinylbenzene, butyl acetate and benzoyl peroxide was injected into a dispersed phase for generating particles, and a 3% aqueous solution of polyvinyl alcohol was injected into a microsyringe as a continuous phase, and the solution was fed. The liquid feeding flow rate is 6 μl / min for both the dispersed phase and the continuous phase. When the flow velocity is stable and the merging part where the dispersed phase and continuous phase of the particle generation microchannel structure intersect is observed, particle generation can be confirmed, but separation and coalescence occur in the discharge channel, When the generated particles (generated particles 23, etc.) are observed, as shown in FIG. 8, the generated particles include not only particles having a particle diameter of about 70 μm, but also particles having a small particle diameter. It was bad. In the case of producing droplets with good dispersibility with this aspect ratio droplet-generating micro-channel structure, the liquid feeding flow rate should be continuous phase> dispersed phase, specifically a flow rate ratio of 5: 1 or more. It is necessary to feed the continuous phase excessively.
(Comparative Example 2)
FIG. 9 shows a fine channel for particle production in Comparative Example 2. As in Example 2, the microchannels are on a polyetherimide of 70 mm × 20 mm × 1 t (thickness), and the widths of the continuous phase introduction channel 3, the dispersed phase introduction channel 5, and the discharge channel 7 are all 140 μm. Y having a depth of 60 μm and a micro-channel aspect ratio = 0.43, and having a junction where the continuous-phase introduction channel 3 and the dispersed-phase introduction channel 5 intersect at an angle of 44 degrees. One letter-shaped channel was formed. Using the same photomask and method as shown in Example 1 as the production method, a flow path was formed on a 200 mm diameter Pyrex (registered trademark) glass substrate, a Ni thin film was formed, and a thickness of 300 μm was formed by electroplating. A stamper was produced and placed in a mold of a molding machine to produce a polyetherimide resin by an injection molding method. The produced flow path substrate was cut out at 70 mm × 20 mm × 1 t.
[0034]
Next, as shown in FIG. 10, the particle manufacturing microchannel structure is held by a holder, and fixed and connected to a Teflon (registered trademark) tube, a fillet joint, and a microsyringe pump. A mixed solution of monomer (styrene), divinylbenzene, butyl acetate and benzoyl peroxide was injected into a dispersed phase for generating particles, and a 3% aqueous solution of polyvinyl alcohol was injected into a microsyringe as a continuous phase, and the solution was fed. The liquid feeding flow rate is 6 μl / min for both the dispersed phase and the continuous phase. When the flow velocity was stable and the merging portion where the dispersed phase and continuous phase of the microchannel structure for particle production intersected was observed, the particle formation phenomenon could not be confirmed and the flow became laminar. Furthermore, the flow rate of the continuous phase was increased so that the particle formation was easy, but the particle formation phenomenon could not be confirmed and a laminar flow was formed.
[0035]
【The invention's effect】
The present invention has the following effects.
(1) The particle production method of the present invention is a method that can cope with industrial mass production because it can produce extremely uniform particles and can control the particle size.
(2) Since the microchannel structure of the present invention can produce particles without depending on the channel material, it is possible to reduce the apparatus cost by using a resin microchannel.
(3) The microchannel structure of the present invention is excellent in particle formation stability and can increase the flow rate of the dispersed phase, so that a large amount of particles can be produced in a short time and can be used industrially. It is.
(4) The microchannel structure according to the present invention is an introductory channel without changing the conditions of the width and depth of the introductory channel of the particle production method microchannel, the liquid phase flow rate of the dispersed phase and continuous phase to be introduced. It is possible to control the generated particle diameter by changing only the angle of the merging portion.
(5) The micro-channel structure of the present invention joins the dispersed phase channel when the angle at which the introducing channel for introducing the dispersed phase and the introducing channel for introducing the continuous phase intersect is less than 90 degrees. By locally narrowing the channel width of the continuous phase channel outlet or discharge channel inlet at the intersection of both channels, and adjusting the combination of the intersection angle and the flow velocity when the intersecting angle is 90 degrees or more As a result, it is possible to stabilize the particle generation site in the vicinity of the merging portion and stably manufacture the particles.
[Brief description of the drawings]
FIG. 1 is a schematic view showing a general micro-channel for particle production.
2 is a schematic view showing a micro-channel structure for producing fine particles used in Example 1. FIG.
3 is a flowchart showing a method for forming a micro-channel for producing fine particles in Example 1. FIG.
4 is a schematic view showing a micro-channel structure for producing fine particles used in Example 1 and Example 2. FIG.
FIG. 5 is a schematic view showing a microchannel structure for producing fine particles and pump connection used in Example 1 and Example 2.
6 is a photograph showing produced particles in Example 1. FIG.
7 is a photograph showing generated particles in Example 2. FIG.
8 is a photograph showing generated particles in Comparative Example 1. FIG.
FIG. 9 is a schematic view showing a microchannel structure for producing fine particles in Comparative Examples 1 and 2.
10 is a schematic view showing a micro-channel structure for producing fine particles and a pump connection in Comparative Examples 1 and 2. FIG.
FIG. 11 is a schematic view showing a micro-channel structure for fine particle generation in which the channel width at the continuous phase channel outlet or the outlet channel outlet of both channel intersections used in Example 3 is narrow. .
12 is a photograph showing generated particles in Example 3. FIG.
FIG. 13 is a schematic view showing a microchannel structure for fine particle generation when a continuous phase intersects with a dispersed phase at an angle of 90 degrees or more.
[Explanation of symbols]
1: Microchannel substrate
2: Continuous phase inlet
3: Continuous phase introduction flow path
4: Dispersed phase inlet
5: Dispersed phase introduction flow path
6: Junction
7: Discharge flow path
8: Discharge port
9: Glass substrate
10: Metal film
11: Photoresist
12: Photomask
13: Substrate on which a microchannel is formed
14: Cover body
15: Microchannel structure
16: Holder
17: Beaker
18: Teflon (registered trademark) tube
19: Fillet joint
20: Micro syringe pump
21: Micro syringe (continuous phase)
22: Micro syringe (dispersed phase)
23: Generated particles
24: Protruding structure provided at the outlet of the continuous phase flow path or the discharge flow path
25: Generated particles

Claims (9)

A dispersed phase introduction flow path through which the dispersed phase is introduced and sent, and a micro flow path through which the continuous phase is introduced and sent, and the end of the dispersed phase introduction flow path sandwiching the dispersed phase introduction flow path from both sides One continuous phase introduction flow path and the other continuous phase introduction flow path intersecting at one point of the section, and from the intersection where the dispersed phase introduction flow path and the two continuous phase introduction flow paths intersect to the discharge port A structure having a micro flow channel having a narrow flow channel at the intersection of the discharge flow channel, and using a structure having a dispersed phase and a continuous phase for the micro flow channel. A method for producing particles, wherein the dispersed phase and the continuous phase are brought into contact with each other at the intersecting portion while being continuously introduced into the structure, and the dispersed phase is sheared into fine particles. The method for producing particles according to claim 1, wherein the continuous phases fed from the two continuous phase introduction flow paths have the same composition. The particle production method according to claim 1 or 2, wherein the dispersed phase is a medium containing a raw material for gel production. The method for producing particles according to any one of claims 1 to 3, wherein the continuous phase is a medium containing a dispersant for gel production. The particle manufacturing method according to claim 4, wherein the gel manufacturing dispersant is polyvinyl alcohol. The method for producing particles according to claim 1, wherein the particles are droplets. A structure having a micro flow path on a substrate, the structure having the micro flow path, a dispersed phase introduction flow path through which a dispersed phase is introduced and fed, and a continuous phase is introduced and fed. One continuous phase introduction channel and the other continuous phase introduction channel that intersect at one point at the end of the dispersed phase introduction channel across the dispersed phase introduction channel from both sides. , The disperse phase introduction flow path and the two continuous phase introduction flow paths intersect with the discharge flow path from the intersection to the discharge opening, and the aspect ratio of the cross section of the discharge flow path (depth of the flow path) / Width ratio) is 0.30 or more, and the width of the discharge channel is narrow at the intersection. 8. The micro-channel structure according to claim 7, wherein the portion where the width of the discharge channel is narrow is on the introduction channel side of the dispersed phase at the intersection of the discharge channel. The introduction flow path for introducing the dispersed phase intersects at an angle that bisects the angle at which the two introduction flow paths for introducing the continuous phase intersect, and the introduction flow path becomes the discharge flow path. The microchannel structure according to claim 7 or 8, wherein the microchannel structure is a connected structure.

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