Process for producing emulsion and microcapsules and apparatus therefor

• US 7,268,167 B2
• Filed: 02/13/2002
• Issued: 09/11/2007
• Est. Priority Date: 02/23/2001
• Status: Expired due to Term

• Current Assignee: National Institute of Advanced Industrial Science and Technology (Government of Japan)
• Original Assignee: Japan Science & Technology Trading Co. Limited
• Inventors: Taniguchi, Tomohiro, Nishisako, Takashi, Torii, Toru, Higuchi, Toshiro
• Primary Examiner(s): Gulakowski; Randy
• Assistant Examiner(s): Kugel; Timothy J.
• Application Number:
  US10/468,015
• Publication Number:
  US 20040068019A1
• Time in Patent Office: 2,036 Days
• Field of Search: 516/9, 516/20, 516/73, 516/924
• US Class Current: 516/9
• CPC Class Codes: B01F 2215/0431 Numerical size values, e.g. diameter of a hole or conduit, area, volume, length, width, or ratios thereof
• CPC Class Codes: B01F 23/41 Emulsifying
• CPC Class Codes: B01F 23/4105 Methods of emulsifying
• CPC Class Codes: B01F 23/4143 Microemulsions
• CPC Class Codes: B01F 23/4144 Multiple emulsions, in particular double emulsions, e.g. water in oil in water; Three-phase emulsions
• CPC Class Codes: B01F 25/313 wherein additional components are introduced in the centre of the conduit
• CPC Class Codes: B01F 25/314 wherein additional components are introduced at the circumference of the conduit
• CPC Class Codes: B01F 25/31422 with a plurality of perforations in the axial direction only
• CPC Class Codes: B01F 33/3011 using a sheathing stream of a fluid surrounding a central stream of a different fluid, e.g. for reducing the cross-section of the central stream or to produce droplets from the central stream
• CPC Class Codes: B01F 33/3031 using electro-hydrodynamic [EHD] or electro-kinetic [EKI] phenomena to mix or move the fluids
• CPC Class Codes: B01F 35/712 for feeding fluids
• CPC Class Codes: B01F 35/71791 using ink jet heads or cartridges, e.g. of the thermal bubble jet or piezoelectric type
• CPC Class Codes: B01F 35/71805 using valves, gates, orifices or openings
• CPC Class Codes: B01J 13/04 by physical processes, e.g. drying, spraying
• CPC Class Codes: B01J 19/0093 Microreactors, e.g. miniaturised or microfabricated reactors laboratory containers with capillary fluid transport in microfabricated channels or chambers B01L3/5027
• CPC Class Codes: B01J 2219/00783 Laminate assemblies, i.e. the reactor comprising a stack of plates
• CPC Class Codes: B01J 2219/00853 Employing electrode arrangements
• CPC Class Codes: B01L 3/5027 by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip B01L3/5023 takes precedence; micromixers B01F33/30; microreactors for synthesis B01J19/0093; microcapillary devices in general B81B1/00
• CPC Class Codes: Y10S 366/04 Micromixers: with application of energy to influence mixing/agitation, e.g. magnetic, electrical, e-m radiation, particulate radiation, or ultrasound
• CPC Class Codes: Y10S 516/924 Significant dispersive or manipulative operation or step in making or stabilizing colloid system
• CPC Class Codes: Y10S 516/927 : in situ formation of a colloid system making or stabilizing agent which chemical reaction
• CPC Class Codes: Y10T 137/0329 : Mixing of plural fluids of diverse characteristics or conditions
• CPC Class Codes: Y10T 428/2984 : Microcapsule with fluid core [includes liposome]

Abstract

A process and apparatus for rapidly producing an emulsion and microcapsules in a simple manner. A dispersion phase is ejected from a dispersion phase-feeding port toward a continuous phase flowing in a microchannel such that flows of the dispersion phase and the continuous phase cross each other, thereby obtaining microdroplets, formed by the shear force of the continuous phase, having a size smaller than the width of the channel for feeding the dispersion phase.

Claims

1. A process for producing an emulsion, comprising a step of ejecting a dispersion phase flowing in a dispersion phase-feeding microchannel from a dispersion phase-feeding port toward a continuous phase flowing in a microchannel in such a manner that flows of the dispersion phase and the continuous phase cross each other and part of the continuous phase extends through the dispersion phase-feeding port, whereby microdroplets are formed by the shear force of the continuous phase, the microdroplets having a diameter smaller than the width of the dispersion phase-feeding micro-channel.

2. A process for producing microcapsules, comprising the steps of:

feeding a first dispersion phase from a first dispersion phase-feeding micro-channel into a continuous phase flowing in a microchannel at a first junction point in such a manner that the continuous phase flows as a layer and the first dispersion phase flows as another layer, thereby forming a two-layered flow; and

feeding a second dispersion phase from a second dispersion phase-feeding micro-channel into the flow of the first dispersion phase in the two-layered flow at a second junction point, whereby microcapsules are formed in the continuous phase, the microcapsules including the second dispersion phase encapsulated by the first dispersion phase as shells.

3. An apparatus for producing an emulsion, comprising:

a main body;

a microchannel formed in the main body, within which a continuous phase flows;

a dispersion phase-feeding micro-channel formed in the main body in a direction to cross the microchannel, the dispersion phase-feeding micro-channel including a dispersion phase-feeding port;

means for feeding a dispersion phase from the dispersion phase-feeding port to the continuous phase in such a manner that flows of the continuous and the dispersion phase cross each other, the dispersion phase-feeding port having a same width as that of the dispersion phase-feeding micro-channel; and

means for forming microdroplets, whereby part of the continuous phase extends through the dispersion phase-feeding port, and microdroplets may be formed by the shear force of the continuous phase, the microdroplets having a diameter smaller than the width of the dispersion phase-feeding micro-channel.

4. The apparatus for producing an emulsion according to claim 3 further comprising films, disposed on portions of inner wall surfaces of the microchannel in which the continuous phase flows and the micro-channel for feeding the dispersion phase, for readily forming the microdroplets, wherein the portions include the junction of the flows of the continuous phase and the dispersion phase and the vicinity of the junction.

5. An apparatus for producing microcapsules, comprising:

a main body;

a microchannel formed in the main body, wherein a continuous phase flows;

a first dispersion phase-feeding micro-channel formed in the main body in direction to cross the microchannel, the first dispersion phase-feeding micro-channel including a first dispersion phase-feeding port to feed a first dispersion phase, wherein the continuous phase in the microchannel and the first dispersion phase from the first dispersion phase-feeding micro-channel form a two-layered flow at the first dispersion phase-feeding port;

a second dispersion phase-feeding micro-channel formed in the main body in a direction to cross the microchannel, the second dispersion phase-feeding micro-channel including a second dispersion phase-feeding port to feed a second dispersion phase, wherein the second dispersion phase may be fed into the first dispersion phase in the two-layered flow at the second dispersion phase-feeding port; and

means for forming microcapsules, whereby microcapsules are formed in the continuous phase, the microcapsules including the second dispersion phase encapsulated by the first dispersion phase as shells.

6. The apparatus for producing microcapsules according to claim 5 further comprising films, disposed on portions of inner wall surfaces of the microchannel in which the continuous phase flows and the micro-channel for feeding the first or second dispersion phase, for readily forming the microdroplets, wherein the portions include the junction of the flows of the continuous phase and the first or second dispersion phase and the vicinity of the junction.