Method for producing uniform particles

• US 4,162,282 A
• Filed: 04/22/1976
• Issued: 07/24/1979
• Est. Priority Date: 04/22/1976
• Status: Expired due to Term

• Current Assignee: Coulter Electronics, Inc.
• Original Assignee: Coulter Electronics, Inc.
• Inventors: Fulwyler, Mack J., Hatcher, C. William
• Primary Examiner(s): Sebastian, Leland A.
• Assistant Examiner(s): Gron, T. S.
• Application Number:
  US05/679,241
• Time in Patent Office: 1,188 Days
• Field of Search: 252/301.1 R, 252/301.1 S, 252/408, 252/301.2 R, 252/301.2 C, 252/316, 264/0.5, 264/9, 264/11, 264/10, 425/7
• US Class Current: 264/9
• CPC Class Codes: B01J 13/04 by physical processes, e.g. drying, spraying
• CPC Class Codes: Y10T 428/2987 Addition polymer from unsaturated monomers only
• CPC Class Codes: Y10T 428/2989 Microcapsule with solid core [includes liposome]
• CPC Class Codes: Y10T 436/101666 Particle count or volume standard or control [e.g., platelet count standards, etc.]

Abstract

Uniform particles are produced by introducing a laminar stream of a core liquid into a laminar flowing body of an immiscible sheath liquid. The core liquid or the sheath liquid, or both liquids, can contain one or more materials dispersed (dissolved or suspended) in them from which the uniform particles are formed. The two liquids and the dispersed material are expelled from a nozzle to form a liquid jet. The liquid jet is disturbed at a uniform, periodic rate to form liquid droplets which contain a uniform amount of the core liquid, the sheath liquid and the dispersed material. The droplets are collected and held in a catch liquid until the core and the sheath liquid in each droplet have diffused into the catch liquid leaving the uniform particles formed from the dispersed materials. There can be more than one sheath liquid which can also contain one or more materials dispersed in it.

Claims

1. A method for producing uniformly sized particles from dispersed material in at least one of a core and sheath liquids said method comprising the steps of:

dispersing at least one particle forming material into at least one of said core and said sheath liquids;

introducing said core liquid into a moving body of at least one sheath liquid;

forming a liquid jet of said core liquid and said sheath liquid;

periodically disturbing said liquid jet to separate said liquid jet including said core and said sheath liquids into unconnected uniform droplets containing a uniform amount of said core liquid, said sheath liquid and said disbursed material;

applying like-repelling charges to each of said uniform droplets; and

forming uniformly sized particles from said uniform droplets.

2. A method of producing particles according to claim 1 wherein the step of dispersing includes:

dispersing at least one particle forming material only into said core liquid.

3. A method of producing particles according to claim 1 wherein the step of dispersing includes:

dispersing at least one particle forming material only into said sheath liquid.

4. A method of producing particles according to claim 1 wherein the step of dispersing includes:

dispersing at least one particle forming material into said core liquid and into said sheath liquid.

5. A method of producing particles according to claim 1 wherein said step of periodically disturbing includes:

uniformly and periodically disturbing said liquid jet in a transverse direction to said liquid jet at a constant rate.

6. A method of producing particles according to claim 1 wherein said step of introducing includes:

introducing said core liquid substantially into the center of said moving body of sheath liquid.

7. A method of producing particles according to claim 1 wherein said step of introducing includes:

introducing said core liquid substantially coaxial with the axis of said moving body of sheath liquid.