JP6091679B1 - Droplet generator - Google Patents

Abstract

Disclosed is a droplet generator that can stably generate uniform droplets and does not accumulate particles. A continuous phase pipe for supplying a continuous phase liquid, a dispersed phase flow path for supplying a dispersed phase liquid, a holding tank connected to the continuous phase pipe and holding the continuous phase liquid, a dispersed phase, and the like. And an anti-deposition portion 14e provided at the tip of the flow path 14. The anti-deposition portion 14e has a conical inclined surface facing the dispersed phase liquid and is formed at the tip of the conical inclined surface. A droplet generator 100 having a hole 14b, and the dispersed phase liquid is sent to the holding tank 10 through the opening 14b. [Selection] Figure 1C

Description

  In the present invention, different types of liquids respectively supplied from a plurality of liquid supply ports are guided to a microchannel, and the liquid is emulsified in the microchannel, and a certain liquid is dispersed as droplets in another liquid. The present invention relates to a droplet generator for obtaining emulsions, that is, emulsions such as [O / W], [(S / O) / W], [W / O], [(S / W) / O].

Conventionally, as a droplet generating device that guides a continuous phase liquid and a dispersed phase liquid to a merging portion and forms droplets of the dispersed phase liquid in the continuous phase liquid at the merging portion, a device described in Japanese Patent No. 3746766 The Royal Society of Chemistry 2008; Soft matter, 2008, 4, 2303-2309 "Fabrication of monodisperse thermosensitive microgels and gel capsules in microfluidic devices" by Rhutesh K. Shah, Jin-Woong Kim, Jeremy J. An apparatus described in Agresti, David A. Weitz, Liang-Yin Chu is known.
These documents discuss the production of droplets with only a single flow path and do not give any explanation regarding industrial production. That is, there has been no description of a plurality of flow paths that efficiently generate droplets with a small variation coefficient.
A parallel type (Fig. 12) in which a disperse phase pump and a continuous phase pump are separately introduced by gathering a plurality of conventional single-channel droplet generators can be considered, but this parallel type is very useful for capillary positioning. Time is required, and the number of dispersed-phase pumps and continuous phase pumps are the same as the number of droplet generators. In fact, non-patent literature requires fine adjustment under a microscope. Further, since the pressure is slightly different for each flow path, the degree of dispersion of the generated droplets is increased. That is, the CV value increases and it is difficult to obtain an emulsion having a uniform particle size. As another example, a configuration (FIG. 13) in which a plurality of conventional single-channel droplet generators are connected together and a plurality of dispersed-phase pumps and a plurality of continuous-phase pumps are combined can be considered. Since the pipe lengths L1, L2 and L3 from the phase pump to the dispersed phase flow path are different, it is difficult to make the resistance in the dispersed phase flow path exactly equal, resulting in a pressure difference and shear force Differences occur. As a result, the diameter of the generated droplets varies greatly and the CV value increases. This fine adjustment of the channel resistance requires a great deal of time and is not suitable for industrial production.
Further, in these documents, the case where the dispersed phase liquid does not contain solid matter and is constituted only by a fluid is described. No problem or solution when the dispersed phase liquid contains a solid is described in any document.

Japanese Patent No. 3746766

The Royal Society of Chemistry 2008; Soft matter, 2008, 4, 2303-2309 "Fabrication of monodisperse thermosensitive microgels and gel capsules in microfluidic devices" by Rhutesh K. Shah, Jin-Woong Kim, Jeremy J. Agresti, David A. Weitz , Liang-Yin Chu

There has been a problem of how to manufacture a plurality of flow paths for industrial production.
In addition, when the dispersed phase liquid contains fine solids, the fine solids may accumulate on the inner wall of the flow path, and the flow path may be clogged or blocked, so that stable droplets cannot be generated. There was a problem.
In view of the above problems, a problem to be solved is to easily generate droplets of uniform size continuously so that the droplets can be mass-produced.

  Another problem is to prevent fine solids from accumulating on the inner wall of the flow path, and to block or close the flow path.

A droplet generator according to an embodiment of the present invention is a droplet generator that guides a continuous phase liquid and a dispersed phase liquid to a merging portion, and forms droplets of the dispersed phase liquid in the continuous phase liquid at the merging portion. A continuous phase pipe for supplying a continuous phase liquid, a holding tank connected to the continuous phase pipe and holding the continuous phase liquid, a plurality of dispersed phase flow paths for supplying the dispersed phase liquid, wherein each dispersed phase flow path One end of the downstream side of the dispersion tank is present in the holding tank, and is formed on the downstream side of each dispersed phase flow path, surrounds the opening, and one end is connected to each dispersed phase flow path, and the other end A plurality of cylindrical or polygonal peripheral walls released in the holding tank, inserted into the inner peripheral walls, one end is located in the holding tank and in the vicinity of the opening, and the other end is It includes a plurality of droplet channels located outside the holding tank.
A droplet generating apparatus according to another embodiment of the present invention guides a continuous phase liquid and a dispersed phase liquid to a merging portion, and forms a droplet of the dispersed phase liquid in the continuous phase liquid at the merging portion. A continuous phase pipe supplying a continuous phase liquid, a dispersed phase flow path supplying a dispersed phase liquid, a holding tank connected to the continuous phase pipe and holding the continuous phase liquid, and if necessary, the dispersed phase And a deposition preventing part provided at the tip of the flow path. Here, the deposition preventing unit has a conical inclined surface facing the dispersed phase liquid, and has an opening formed at the tip of the conical inclined surface, and the dispersed phase liquid is supplied to the holding tank through the opening. Sent out. Furthermore, the droplet generator of the present invention includes a cylindrical or polygonal peripheral wall surrounding the opening, having one end connected to the deposition preventing portion and the other end being released into the holding tank, and the cylindrical or multiple A droplet passage is inserted into the rectangular peripheral wall and has one end in the holding tank and located near the opening and the other end located outside the holding tank.

  Further, when preparing a composite emulsion such as [(S / O) / W] and [(S / W) / O], a conical inclined surface is provided on the upstream side of the opening of the dispersed phase channel. As a result, it is possible to prevent the fine solids (S) contained in the dispersed phase liquid from slipping down and accumulating, and to prevent clogging and blockage of the flow path. Thereby, stable and uniform size droplets can be easily and continuously generated, and the droplets can be mass-produced.

  Since the continuous phase liquid flows along the tip surface and the continuous phase liquid can be concentrated to generate a concentrated flow in the direction of the opening, the droplet size can be made uniform.

1 is a cross-sectional view of a droplet generation device according to a first embodiment of the present invention. Sectional drawing of the droplet generation apparatus which concerns on the reference example of 1st Embodiment of this invention. Sectional drawing of the droplet production | generation apparatus which concerns on 2nd Embodiment of this invention. Sectional drawing of the droplet generation apparatus which concerns on the modification of 2nd Embodiment of this invention. Sectional drawing of the droplet generation apparatus which concerns on another modification of 2nd Embodiment of this invention. The enlarged view of the droplet production | generation part shown to FIG. 1C. FIG. 3 is a modified view of the embodiment shown in FIG. 2. FIG. 4 is another modified view of the embodiment shown in FIG. 2. FIG. 6 is still another modification of the embodiment shown in FIG. 2. FIG. 6 is still another modification of the embodiment shown in FIG. 2. Sectional drawing of the droplet production | generation apparatus which concerns on 3rd Embodiment of this invention. The modification of embodiment shown to FIG. 7A. FIG. 7B shows another modification of the embodiment shown in FIG. 7A. FIG. 7A shows still another modification of the embodiment shown in FIG. 7A. FIG. 7A shows still another modification of the embodiment shown in FIG. 7A. FIG. 7B is still another modification of the embodiment shown in FIG. 7A. FIG. 7B is still another modification of the embodiment shown in FIG. 7A. The conceptual diagram which gathered together the conventional droplet production | generation apparatus of the single flow path. The conceptual diagram which connected the conventional droplet production | generation apparatus of the single flow path.

  FIG. 1A shows a first embodiment of a droplet generator 100 according to the present invention. The droplet generator 100 includes a continuous phase pump 2, a dispersed phase pump 4, a product tank 6, and a holding tank 10. For example, when preparing an O / W, (S / O) / W emulsion, a continuous phase liquid, such as water, preferably water containing a surfactant, is delivered from the continuous phase pump 2, and the continuous phase pipe 12 is supplied. And is fed into a sealed holding tank 10. The holding tank 10 is filled with a continuous phase liquid. From the dispersed phase pump 4, a dispersed phase liquid, for example, oil containing oil or fine solids is sent out and sent to the droplet generation unit 18 in the holding tank 10 through the dispersed phase flow path 14. In the droplet generation unit 18, the dispersed phase liquid becomes droplets ET (emulsion), and the droplets ET are mixed with the continuous phase liquid to become a mixed liquid and are collected in the product tank 6 through the droplet channel 16. The holding tank 10, the continuous phase pipe 12, the dispersed phase flow path 14, and the droplet flow path 16 are made of, for example, glass, metal, plastic, etc., and the surface wetted parts thereof are [W / O], [(S / W) / O] Hydrophobic treatment during emulsion preparation, [O / W], [(S / O) / W] Hydrophilization treatment during emulsion preparation. Even if the continuous phase pump 2, the dispersed phase pump 4, and the product tank 6 are not provided, the droplet generating device 100 is established as a product.

In this embodiment, droplets of oil (O) containing fine solids (S) are generated in water (W), so-called solid-in-oil-in-water [( S / O) / W] will be described in the form of a droplet generator. However, the present invention relates to other forms, such as [O / W], [W / O], [(S / W) / O], etc. Needless to say, is also available.
In the first embodiment shown in FIG. 1A, a deposition preventing unit 14e described in detail in FIG. 2 is further provided.
Figure 1B illustrates a reference example of FIG. 1A, the deposition preventing part 14e shown in this reference example in FIG. 1A is omitted. In this reference example , the inner surface of the peripheral wall 20 surrounding the tip of the droplet flow path 16 is surface-treated with a hydrophobic material when producing a [W / O] or [(S / W) / O] emulsion. On the other hand, when an [O / W] or [(S / O) / W] emulsion is produced, the surface treatment is performed with a hydrophilic material. The same applies to other modified examples and embodiments.
FIG. 1C shows a second embodiment of the droplet generator 100. In the first embodiment, the droplet generation unit 18 is configured with a single flow path, but in the second embodiment, the droplet generation unit 18 is configured with multiple channels. When the peripheral wall 20 is viewed from the dispersed phase flow path 14 side, the peripheral wall 20 has two circles adjacent to each other like a figure of eight. A separation wall 19 exists between the adjacent droplet generation units 18, and a deposition prevention unit 14 e that is thicker than the separation wall 19 is formed at the upper end of the separation wall 19 (the side where the dispersed phase flow path 14 exists). Is provided. The accumulation preventing part 14e has a funnel-shaped inclined surface, and an opening 14b is formed at the center of the funnel-shaped inclined surface. In this embodiment, the diameter of the opening 14 b is equal to or smaller than the diameter of the droplet channel 16. The diameter of the opening 14 b may be larger than the diameter of the droplet channel 16. The end of the dispersed phase flow path 14 exists in the holding tank 10, and a plurality of apertures 14 b are formed at the downstream end of the dispersed phase flow path 14. Further, there is provided a peripheral wall 20 having a plurality of cylindrical or polygonal inner walls that surround each of the plurality of apertures 14b, one end is connected to the end of the dispersed phase flow path 14, and the other end is released into the holding tank. It has been. The separation wall 19 constitutes a part of the peripheral wall 20. Further, a plurality of droplet passages that are inserted inside each of the plurality of peripheral walls 20, one end is located in the holding tank 10, near the opening, and the other end is located outside the holding tank 10. 16
FIG. 1D shows a modification of FIG. 1C. In this modification, the deposition preventing portion 14 e shown in FIG. 1C is formed with the same thickness as the thickness of the separation wall 19. The upper end of the separation wall 19 is tapered.
FIG. 1E shows another modification of FIG. 1C, and in this modification, the deposition preventing portion 14 e is formed on the peripheral wall 20 including the separation wall 19.

  FIG. 2 shows the details of the second embodiment (FIG. 1C) that includes the accumulation preventing unit 14e of the droplet generation unit 18 and has multiple flow paths.

  The dispersed phase flow path 14 is a cylindrical or polygonal flow path, and a plurality of conical inclined surfaces 14c are provided on the most downstream side, and a fine opening 14b is formed at the tip of each inclined surface 14c. Is formed. The distal end surface 14a of the dispersed phase flow path 14 exists inside the holding tank 10, and the dispersed phase liquid flows out from the fine opening 14b. The diameter D1 of the opening 14b is a size suitable for forming a droplet (emulsion), and is, for example, about 10 μm to 5 mm, preferably about 100 μm. The diameter D1 can be determined by the size (diameter) of the droplet. The opening 14b has a predetermined thickness (about 10 μm to 5 mm) in the axial direction. The dispersed phase liquid is guided to the opening 14b together with the fine solids by the conical inclined surface 14c. The inclined surface 14c when cut in the axial direction of the dispersed phase flow path 14 is linearly inclined at an angle of approximately 45 degrees with respect to the coaxial direction. The upstream side of the inclined surface 14 c is connected to the inner peripheral surface 14 d of the dispersed phase flow path 14. A deposition preventing portion 14e is formed in a portion surrounded by the front end surface 14a, the opening 14b, and the inclined surface 14c. That is, the deposition preventing portion 14e provided on the downstream side of the dispersed phase flow path 14 has a conical inclined surface 14c facing the dispersed phase liquid and an opening 14b formed at the tip of the conical inclined surface. Therefore, the fine solid matter is sent to the holding tank through the opening without being deposited by the dispersed phase liquid flowing on the inclined surface.

  A cylindrical or polygonal peripheral wall 20 surrounding the opening 14b is formed at the tip of the distal end surface 14a. One end of the peripheral wall 20 is connected to the deposition preventing portion 14 e, and the other end 20 a is released in the holding tank 10. The dispersed phase flow path 14 and the peripheral wall 20 may be configured integrally or may be configured separately. The length D2 of the peripheral wall 20 is about 100 μm to several tens of mm. A cylindrical space 20c is formed by the inner peripheral surface 20b inside the peripheral wall 20 and the tip surface 14a. The diameter D3 of the inner peripheral surface 20b is about 1000 μm to several tens of mm.

  The droplet channel 16 is a channel thinner than the inner peripheral surface 20b of the peripheral wall 20, and the inner diameter D4 of the inner peripheral surface 16b of the droplet channel 16 is about 1/2 to 4/5 of the inner diameter D3. The tip end portion of the liquid droplet flow path 16 having a cylindrical shape is coaxially (concentrically) inserted into the space 20c. The inserted length D5 is, for example, about 100 μm to several tens of mm. A gap is provided between the tip 16a of the droplet channel 16 and the tip surface 14a. The gap length D6 is about 10 μm to 5 mm.

  With the above configuration, the continuous phase flow path 22 is formed between the inner peripheral surface 20 b of the peripheral wall 20 and the outer peripheral surface of the droplet flow path 16.

  The inlet 22 a of the continuous phase channel 22 is formed at the tip 20 a of the peripheral wall 20, from which water (preferably water containing a surfactant) as a continuous phase fluid is guided to the continuous phase channel 22. In the middle of the continuous phase flow path 22, there is a continuous phase-dispersed phase confluence portion 22b in which droplets ET are generated. The outlet 22c of the continuous phase channel 22 is formed at the tip 16a of the droplet channel 16, from which a mixed liquid ([O / W], [O / W], [(S / O) / W] emulsion) is delivered through the droplet channel 16.

  As shown in FIG. 1C and FIG. 2, water (preferably water containing a surfactant) that is a continuous phase liquid fed from the continuous phase pump 2 is fed into the holding tank 10, as indicated by an arrow A. Inflow from the inlet 22 a of the continuous phase flow path 22. The continuous phase liquid flows into the continuous phase flow path 22, is guided along the distal end surface 14 a of the dispersed phase flow path 14, and concentrates on the opening 14 b as indicated by an arrow B. As indicated by the arrow B, the fluid flowing from the direction of 360 degrees toward the center of the opening 14b is called a concentrated flow. On the other hand, from the disperse phase pump 4, oil mixed with fine solids, which is a disperse phase liquid, passes through the disperse phase channel 14 and is released downward (in the direction of the droplet channel 16) from the opening 14 b. . At this time, the dispersed phase liquid discharged from the opening 14b is dropped and sheared by the concentrated flow. The droplet ET is generated between the junction 22b and the outlet 22c. The generated droplet ET is mixed with the continuous phase liquid and travels toward the outlet 22c. Thereby, the mixed liquid ([O / W], [(S / O) / W] emulsion) in which the droplet ET and the continuous phase liquid are mixed from the outlet 22c passes through the droplet flow path 16 and the product tank. Collected in 6. The continuous phase pump 2 should just send out a continuous phase liquid with the flow volume pressure which adjusts the strength of the concentrated flow made with a continuous phase liquid. Moreover, the dispersed phase pump 4 should just send out a dispersed phase fluid with the flow volume pressure which adjusts the speed at which a dispersed phase fluid passes the opening 14b. Thereby, the flow pressure of the pumps 2 and 4 is adjusted.

  Since one surface of the deposition preventing portion 14e faces the dispersed phase liquid and is provided with a conical inclined surface 14c, it prevents the fine solids contained in the dispersed phase liquid from sliding down and accumulating. It is possible to prevent clogging and blockage of the flow path.

  Since the continuous phase liquid flows along the tip surface 14a and the continuous phase liquid can be concentrated to generate a concentrated flow toward the opening 14b, the size of the droplets can be made uniform. The droplet size also depends on the size of the opening 14b and the pore diameter of the outlet 22c.

Examples of the surfactant contained in the continuous phase liquid include an anionic surfactant, a cationic surfactant, and a nonionic (polymer) surfactant. More specifically, examples of the anionic surfactant include sodium polyacrylate, polysodium methacrylate, potassium polyacrylate, and polypotassium methacrylate. Sodium lauryl sulfate as alkyl sulfate ester salt. As polyoxyethylene alkyl ether sulfate ester salt, polyoxyethylene lauryl ether sodium sulfate, polyoxyethylene lauryl ether potassium sulfate, polyoxyethylene alkyl ether sulfate triethanolamine. Alkylbenzene sulfonates include dodecyl benzene sulfonic acid, sodium dodecyl benzene sulfonate, and potassium dodecyl benzene sulfonate. Other sulfonates include sodium alkyl naphthalene sulfonate, potassium alkyl naphthalene sulfonate, sodium dialkyl sulfosuccinate, potassium dialkyl sulfosuccinate, sodium alkyl diphenyl ether disulfonate, potassium alkyl diphenyl ether disulfonate, sodium alkane sulfonate, and potassium alkane sulfonate. As fatty acid salts, semi-cured beef tallow fatty acid sodium, semi-cured beef tallow fatty acid potassium, sodium stearate, potassium stearate, sodium oleate, potassium oleate, castor oil fatty acid sodium, castor oil fatty acid potassium , other alkenyl succinate dipotassium, alkenyl Examples include disodium succinate and ammonium polyoxyalkylene alkenyl ether sulfate. Examples of cationic surfactants include polyethyleneimine and polyacrylamide. Coconutamine acetate and stearylamine acetate as alkylamine salts. Examples of the quaternary ammonium salt include lauryltrimethylammonium chloride, stearyltrimethylammonium chloride, cetyltrimethylammonium chloride, distearyldimethylammonium chloride, and alkylbenzyldimethylammonium chloride. Nonionic surfactants include polyvinyl alcohol, polyvinyl pyrrolidone, block copolymers and triblock polymers synthesized by precision polymerization (ATRP, ICAR, AGET, Reverse ASTRP, RAFT, NMP) such as atom transfer radical polymerization. Specifically, polymethylmethacrylate-b-polyacrylic acid block copolymer, polymethylmethacrylate-b-polymethacrylic acid block copolymer, polymethylmethacrylate-b-polyvinylpyrrolidone block copolymer, polymethylmethacrylate-b- Poly 2-hydroxymethacrylate block copolymer, polymethyl methacrylate-b-polyvinyl alcohol block copolymer, polymethyl methacrylate-b-polyethylene glycol block copolymer, polymethyl acrylate-b-polyacrylic acid block copolymer, polymethyl acrylate-b -Polymethacrylic acid block copolymer, polymethyl acrylate-b-polyvinylpyrrolidone block copolymer, polymethyl acrylate-b-poly 2-hydroxymethacrylate Relate block copolymer, polymethyl acrylate-b-polyvinyl alcohol block copolymer, polymethyl acrylate-b-polyethylene glycol block copolymer, polystyrene-b-polyacrylic acid block copolymer, polystyrene-b-polymethacrylic acid block copolymer, polystyrene-b -Polyvinylpyrrolidone block copolymer, polystyrene-b-poly 2-hydroxymethacrylate block copolymer, polystyrene-b-polyvinyl alcohol block copolymer, polystyrene-b-polyethylene glycol block copolymer and the like.

  Examples of the dispersed phase liquid include preferably a water-insoluble organic solvent such as methyl methacrylate (MMA), methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, and tertiary butyl acetate. Solutes include polymethyl methacrylate, polyethyl methacrylate, polypropyl methacrylate, polyisopropyl methacrylate, polybutyl methacrylate, polytertiary butyl methacrylate, polymethyl acrylate, polyethyl acrylate, polypropyl acrylate, polyisopropyl acrylate, polybutyl acrylate, poly Examples include tertiary butyl acrylate, polymethyl methacrylate-polyethyl methacrylate copolymer, and polymethyl acrylate-polyethyl acrylate copolymer.

An example of the fine solid is preferably a dental inorganic glass composition. In particular, an ion sustained-release glass that releases fluorine ions and the like is preferable. The ion sustained-release glass can be used without any limitation as long as it contains one or more kinds of glass skeleton forming elements that form a glass skeleton and one or more kinds of glass modifying elements that modify the glass skeleton. In the present invention, an element that can be a glass skeleton forming element or a glass modifying element depending on the glass composition, so-called glass amphoteric element, is included as a category of the glass skeleton forming element. Specific examples of the glass skeleton-forming elements contained in the sustained-release glass include silica, aluminum, boron, phosphorus and the like, but they can be used alone or in combination. Specific examples of glass modifying elements include halogen elements such as fluorine, bromine and iodine, alkali metal elements such as sodium and lithium, alkaline earth metal elements such as calcium and strontium, etc. In addition to the above, a plurality can be used in combination. Among these, it is preferable to include silica, aluminum, and boron as glass skeleton forming elements, and fluorine, sodium, and strontium as glass modifying elements. Specifically, silica glass including strontium and sodium, fluoroaluminosilicate glass, Examples thereof include fluoroborosilicate glass and fluoroaluminoborosilicate glass. Furthermore, from the viewpoint of sustained release of fluoride ions, strontium ions, aluminum ions, and borate ions, it is more preferably fluoroaluminoborosilicate glass containing sodium and strontium, and the glass composition range is SiO ₂ 15 to 35 mass. %, Al ₂ O ₃ 15-30% by mass, B ₂ O ₃ 5-20% by mass, SrO 20-45% by mass, F 5-15% by mass, Na ₂ O 0-10% by mass. Di-t-butyl peroxide, dicumyl peroxide, t-butyl cumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 1,3-bis (t- Organic peroxide fine powders such as butylperoxyisopropyl) benzene and 2,5-dimethyl-2,5-di (t-butylperoxy) -3-hexyne are also preferably used. Furthermore, barbituric acid and its derivative fine powder are also preferable. For example, barbituric acid, 1,3,5-trimethylbarbituric acid, 1,3-diphenylbarbituric acid, 1,5-dimethylbarbituric acid, 5-butylbarbituric acid, 5-ethylbarbituric acid, 5 -Isopropylbarbituric acid, 5-cyclohexylbarbituric acid , 1,3-dimethyl-5-ethylbarbituric acid, 1,3-dimethyl-5-n-butylbarbituric acid, 1,3-dimethyl-5-isobutyl Barbituric acid , 1,3-dimethyl-5-cyclopentylbarbituric acid, 1,3-dimethyl-5-cyclohexylbarbituric acid, 1,3-dimethyl-5-phenylbarbituric acid, 1-cyclohexyl- 5 -ethyl Barbituric acid, 1-benzyl-5-phenylbarbituric acid, 5-methylbarbituric acid, 5-propylbarbituric acid, 1,5-diethylbarbituric acid, 1-ethyl-5-methylbarbituric acid, 1 -Ethyl-5-isobutylbarbituric acid 1,3-diethyl-5-butylbarbituric acid, 1-cyclohexyl-5-methylbarbituric acid, 1-cyclohexyl-5-ethylbarbituric acid, 1-cyclohexyl-5-octylbarbituric acid, 1-cyclohexyl -5-hexylbarbituric acid, 5-butyl-1-cyclohexylbarbituric acid, 1-benzyl-5-phenylbarbituric acid and thiobarbituric acids, and their salts (especially alkali metals or alkaline earth metals) Examples of these salts of barbituric acids include sodium 5-butyl barbiturate, sodium 1,3,5-trimethylbarbiturate and sodium 1-cyclohexyl-5-ethylbarbiturate. A barbituric acid derivative fine powder is also mentioned. Specific examples of particularly suitable barbituric acid derivatives include, for example, 5-butyl barbituric acid, 1,3,5-trimethylbarbituric acid, 1-cyclohexyl-5-ethylbarbituric acid, 1-benzyl-5 -Phenyl barbituric acid and sodium salts of these barbituric acids.

  The droplet generation device according to the present invention is configured assuming that oil containing fine solids is used as the dispersed phase liquid, but it is also possible to use oil that does not contain fine solids. Needless to say.

  FIG. 3 shows a modification of the inclined surface 14c. The inclined surface 14c cut in the axial direction draws an S-shaped curve. Thereby, precipitation of a fine solid substance can be prevented more efficiently.

  FIG. 4 shows a modification of the continuous phase flow path 22. The inner peripheral surface 20b and the front end surface 14a are connected by a bending portion 20d. By doing so, a concentrated flow can be efficiently generated, and the flow of the continuous phase liquid can be stably directed toward the opening 14b.

  FIG. 5 shows another modification of the continuous phase flow path 22. A portion of the front end surface 14 a adjacent to the opening 14 b is curved in the direction of the droplet channel 16. On the downstream side of the opening 14b, a rising portion 14f is formed such that the direction in which the continuous phase liquid flows and the direction in which the dispersed phase liquid flows are acute angles. By doing so, the flow of the continuous phase liquid can be further stabilized and the droplet size can be made uniform. It is also possible to increase the generation speed of the droplet ET.

  FIG. 6 shows a modification of the droplet channel 16. The droplet channel 16 shown in FIG. 2 is cylindrical, and the tip portion close to the opening 14b is also cylindrical. In the modification shown in FIG. 6, the tip portion is tapered and narrows toward the opening 14b.

  In this way, by making the tip portion of the droplet flow channel 16 tapered, the flow of the continuous phase liquid fed into the droplet flow channel 16 from the outlet 22c of the continuous phase flow channel 22 becomes steeper. The flow force (shearing force) that breaks the droplets becomes stronger, and uniform size droplets can be reliably generated at a higher speed.

  The above modifications may be employed alone or in combination. Moreover, you may employ | adopt also in 2nd Embodiment demonstrated below and its modification.

  FIG. 7A shows a third embodiment of a droplet generator 200 according to the present invention. In the first and second embodiments, the droplet generation unit 18 is provided in the holding tank 10, but in the third embodiment, the droplet generation unit 18 is formed in one intermediate layer 32. In the intermediate layer 32, a plurality of, for example, four droplet generation units 18 are provided in parallel. The same reference numerals are used for the same parts as those shown in the first embodiment, and detailed description thereof is omitted.

  The droplet generation device 200 is provided with a supply tank 30 that supplies a dispersed phase liquid different from the holding tank 10 that holds the continuous phase liquid. An intermediate layer 32 constituting the droplet generation unit 18 is provided between the holding tank 10 and the supply tank 30. The supply tank 30 is connected to a dispersed phase pipe 11 for feeding the dispersed phase liquid from the dispersed phase pump 4. A rectangular space is formed on the inner wall of the supply tank 30. Although the supply tank 30 is provided with an air vent port 15 for venting air, the port 15 may be omitted.

  The intermediate layer 32 is formed with a cylindrical through hole 20c corresponding to the space 20c of the first embodiment. The inner wall of the through hole 20c corresponds to the peripheral wall 20 of the first embodiment. A plurality of through-holes 20c, here four, are formed in parallel. Therefore, a plurality of peripheral walls 20 are formed in parallel. The tip of the droplet channel 16 is coaxially inserted into the through hole 20c. The holding tank 10, the supply tank 30, and the intermediate layer 32 are made of, for example, glass, metal, plastic, etc., and the surface wetted part is necessary when preparing [W / O] and [(S / W) / O] emulsions. Hydrophobization treatment, [O / W], [(S / O) / W] When preparing an emulsion, it is hydrophilized.

The inner wall of the supply tank 30 functions as the dispersed phase flow path 14 for supplying the dispersed phase liquid. The supply tank 30 is provided with a deposition preventing portion 14e formed by four conical inclined surfaces 14c, and an opening 14b is formed at the center of each deposition preventing portion. The center of the opening 14b is located at the center of the through hole 20c. Further, the outer surface of the deposition preventing portion 14e corresponds to the tip surface 14a of the first embodiment, and the inner surface of the deposition preventing portion 14e corresponds to the inclined surface 14c of the first embodiment.
FIG. 7B shows a modification of the droplet generation device 200 shown in FIG. 7A. In the modification of FIG. 7B, the opening 14b provided at the tip of the inclined surface 14c has a predetermined length like a tunnel. Therefore, the inclined surface 14c and the opening 14b are formed in a funnel shape.
FIG. 7C shows another modification of the droplet generation device 200 shown in FIG. 7A. In the modification of FIG. 7C, there is no inclined surface 14 c and the through hole 20 c of the intermediate layer 32 is an opening of the supply tank 30.
In the modification of FIG. 7C, the CV value is low because a uniform pressure is applied to all the capillaries as compared with the case where the droplet generation unit as shown in FIG. 12 is configured separately. That is, the degree of dispersion of the droplets is low. Capillary positioning can also be performed instantaneously by using a convex jig or the like.

  FIG. 8 shows still another modification of the droplet generation device 200 shown in FIG. 7A. In the modification of FIG. 8, the axial direction of the dispersed phase pipe 11 passes through the center of the surface surrounding the deposition preventing portion 14e formed by the plurality of conical inclined surfaces 14c and is perpendicular to the surface. The disperse phase pipe 11 is provided in a positional relationship.

  With the configuration of the modified example of FIG. 8, the liquid pressure of the dispersed phase liquid sent to each deposition preventing unit 14 e can be made substantially uniform. Thereby, stable and uniform size droplets can be easily and continuously generated, and the droplets can be mass-produced.

  FIG. 9 shows still another modification of the droplet generation device 200 shown in FIG. 7A. 9 is a modification of the modification of FIG. 8 in which the inner wall of the supply tank 30 is formed in a dome shape. It is also possible to change to a dome shape and to make a cone shape. In this way, the flow of the dispersed phase in the dome can be made more uniform overall.

  Further, in the modification of FIG. 9, the opening 14b is formed to be approximately the same size as the inner peripheral surface 20b. By doing so, the size of the droplet ET and the generation rate of the droplet can be set to a desired size and a desired rate. The modification in which the opening 14b is formed to have approximately the same size as the inner peripheral surface 20b can be applied to the first, second, and third embodiments and the modification.

  FIG. 10 shows still another modification of the third embodiment. In the modified example of FIG. 10, the dispersed phase flow path 14 is provided in the supply tank 30 connected to the dispersed phase pipe 11, and a plurality of dispersed phase flow paths 14 are provided, and in the modified example of FIG. The branching channels 14w, 14x, 14y, and 14z are branched. The four branch channels 14w, 14x, 14y, and 14z extend radially from the tip of the dispersed phase pipe 11 and extend to a position where the opening 14b is formed, that is, a position where a through hole is formed. In this way, the four branch channels supply the dispersed phase liquid to the four droplet generation units 18, respectively. In addition, since all of the four branch channels are connected to the opening 14b by the inclined surface 14c, the inclined surface 14c functions as the above-described deposition preventing portion. In the case of this form, it is desirable that the distances of the four branch channels 14w, 14x, 14y, and 14z, that is, the distances from the 11 terminal to 14a are as equal as possible. By doing so, the resistance of the flow path becomes uniform and the droplet discharge amount and the CV value of the particle diameter become uniform.

  As shown in FIG. 10, by dividing the dispersed phase flow path into a plurality of divided flow paths, the dispersed phase liquid can be supplied to each droplet generation unit 18 with an equal pressure. Therefore, it is possible to generate droplets between the four droplet generation units 18 with the same efficiency without any inferiority.

  FIG. 11 shows still another modification of the third embodiment. The modification shown in FIG. 11 is a modification of the modification shown in FIG. 10, and a spherical liquid reservoir 14g is formed at the branch point of the four branch channels 14w, 14x, 14y, and 14z.

  By providing the liquid reservoir 14g, even if the dispersed-phase liquid sent from the dispersed-phase pipe 11 pulsates and the fluid pressure is strong or weak, the pulsating fluid pressure in the liquid reservoir 14g is reduced, and the branch flow path 14w. , 14x, 14y, and 14z, the dispersed phase liquid can be delivered at a uniform liquid pressure. As a result, the droplet generator 18 can generate uniform droplets.

  10 and 11, the air vent port 15 is omitted, but it may be provided if necessary.

  The droplet generator described herein can be used in the industry for generating droplets.

2 ... continuous phase pump, 4 ... dispersed phase pump, 6 ... product tank,
10 ... holding tank, 11 ... disperse phase pipe, 12 ... continuous phase pipe,
14 ... disperse phase flow path, 14a ... tip surface, 14b ... opening, 14c ... inclined surface,
14d ... Inner peripheral surface, 14e ... Deposition prevention part, 14w, 14x, 14y, 14z ... Split flow path, 14g ... Liquid storage, 15 ... Air venting port,
16 ... droplet flow path, 18 ... droplet generator, 20 ... peripheral wall, 20a ... other end,
20b ... inner peripheral surface, 20c ... space, 20d ... curved part, 22 ... continuous phase flow path, 22a ... inlet, 22b ... continuous phase-dispersed phase joining part, 22c ··Exit,
30 ... supply tank, 32 ... intermediate layer, ET ... droplet

Claims (16)

A droplet generating device that guides a continuous phase liquid and a dispersed phase liquid to a merging portion, and forms droplets of the dispersed phase liquid in the continuous phase liquid at the merging portion,
Continuous phase pipe supplying continuous phase liquid,
A holding tank connected to the continuous phase pipe and holding a continuous phase liquid;
The dispersed phase flow path for supplying the dispersed phase liquid, where the downstream end of the dispersed phase flow path exists in the holding tank,
A plurality of apertures formed at the downstream end of the dispersed phase flow path,
A plurality of cylindrical or polygonal peripheral walls surrounding each of the plurality of apertures, one end connected to the end of the dispersed phase flow path and the other end released into the holding tank;
The deposition preventing part provided at one end of the plurality of peripheral walls, wherein the deposition preventing part has an inclined surface that is inclined with respect to the flowing direction of the dispersed phase liquid.
Inserted inside each of the plurality of peripheral walls, and includes a plurality of droplet flow paths having one end in the holding tank and located near the opening and the other end located outside the holding tank. Droplet generator. A droplet generating device that guides a continuous phase liquid and a dispersed phase liquid to a merging portion, and forms droplets of the dispersed phase liquid in the continuous phase liquid at the merging portion,
Continuous phase pipe supplying continuous phase liquid,
A dispersed phase flow path for supplying the dispersed phase liquid;
A holding tank connected to the continuous phase pipe and holding a continuous phase liquid;
The deposition preventing part provided on the downstream side of the dispersed phase flow path, wherein the deposition preventing part has an inclined surface that is inclined with respect to the flowing direction of the dispersed phase liquid , and an opening formed at the tip of the inclined surface The dispersed phase liquid is delivered to the holding tank through the apertures,
A cylindrical or polygonal peripheral wall that surrounds the opening, has one end connected to the anti-deposition unit, and the other end released into the holding tank;
A droplet generation device including a droplet flow path that is inserted inside the peripheral wall and has one end in the holding tank and located near the opening and the other end located outside the holding tank.   The droplet generating device according to claim 2, wherein the inclined surface has a conical shape. The droplet generation device according to claim 2, wherein an edge of a cross section of the inclined surface is a straight line when the inclined surface is cut along a flowing direction of the dispersed phase liquid . The droplet generation device according to claim 2, wherein an edge of a cross section of the inclined surface is a curve when the inclined surface is cut along a flowing direction of the dispersed phase liquid .   The droplet generation device according to claim 2, wherein a curved portion is formed at a connection portion between the tip surface of the deposition preventing portion and the inner wall of the peripheral wall. The droplet generating device according to claim 2, wherein a swelled portion is formed on the downstream side of the opening so that an angle formed by a direction in which the continuous phase liquid flows and a direction in which the dispersed phase liquid flows is an acute angle .   The droplet generating device according to claim 2, wherein the one end of the droplet channel is tapered.   The droplet generator of claim 2 further comprising a supply tank that holds the dispersed phase liquid. Further, between the supply tank and the holding tank, the intermediate layer is provided, a plurality of parallel through holes in the intermediate layer is formed, the wall portion surrounding the through-holes function as the peripheral wall, claim 9. A droplet generator according to item 9.   The droplet generator according to claim 9, wherein an inner wall of the supply tank is rectangular.   The droplet generation device according to claim 9, wherein an inner wall of the supply tank has a dome shape. A dispersed phase flow path is formed on the inner wall of the supply tank, and the dispersed phase flow path has a configuration that branches into a plurality of radially extending branch flow paths, each of which has a plurality of through holes. The droplet generator according to claim 10, which extends to a certain position.   The droplet generator according to claim 13, wherein a liquid reservoir is provided at a branch point of the dispersed phase flow path. The droplet generating device according to claim 1, wherein the inner surface of the peripheral wall is surface-treated with a hydrophilic material. The droplet generating device according to claim 1, wherein the inner surface of the peripheral wall is surface-treated with a hydrophobic material.

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