Including Extruding (e.g., Spinning, Etc.) Patents (Class 264/433)
  • Patent number: 6045835
    Abstract: A method of encapsulating an amphiphilic flavor or fragrance compound into a microcapsule having a hydrogel shell and an oil core. The flavor or fragrance compound is transported into and solubilized in the core by partition coefficient equilibrium using water in the capsule wall to transport the compound into the core. Microcapsules made by the method of the invention may have a wall thickness and contain a high concentration of the flavor or fragrance compound that has not previously been feasible.
    Type: Grant
    Filed: October 9, 1997
    Date of Patent: April 4, 2000
    Assignee: Givaudan Roure (International) SA
    Inventors: Jon C. Soper, Young D. Kim, Margaret T. Thomas
  • Patent number: 6039901
    Abstract: Enzymatic cross-linking of protein-encapsulated oil particles by complex coacervation. A complex coacervate of oil particles, each encapsulated in a protein shell, is stabilized by gelling the protein shell and is subsequently enzymatically cross-linked to form thermostable capsules of about 100-300 microns. The preferred enzyme is transglutaminase, and the reaction is performed at pH 7 to achieve the optimal cross-linking rate. The transglutaminase-catalyzed cross-linking reaction takes place with the complex coacervate maintained at a temperature in the range of about 5.degree. C.-10.degree. C. to maintain the structural stability of the complex coacervate.
    Type: Grant
    Filed: January 31, 1997
    Date of Patent: March 21, 2000
    Assignee: Givaudan Roure Flavors Corporation
    Inventors: Jon C. Soper, M. Teresa Thomas
  • Patent number: 6039900
    Abstract: A dispersion is formed of aqueous polymer particles in a non-aqueous liquid and a stabiliser is covalently reacted on to the particles.
    Type: Grant
    Filed: June 30, 1998
    Date of Patent: March 21, 2000
    Assignee: Allied Colloids Limited
    Inventors: Kenneth Charles Symes, Kishor Kumar Mistry
  • Patent number: 6036976
    Abstract: Disclosed is a method of producing microspheres which comprises subjecting a w/o/w emulsion or o/w emulsion to an in-water drying method under the following conditions:1) the amount of microspheres per m.sup.3 of an external aqueous phase is about 0.1 to about 500 kg,2) the square root of the area (unit: m.sup.2) of the liquid surface in contact with the gas phase is about 0.2 to about 4.5 per the cube root of the volume (unit: m.sup.3) of an external aqueous phase,3) the w/o/w emulsion or o/w emulsion is replaced at the replacement frequency of about 0.01 to about 10 times/minutes,4) a gas is blown to the w/o/w emulsion or o/w emulsion at the gas transfer rate near the liquid surface of about 0.1 to about 300 m/second, and5) the gas is replaced at the replacement frequency of not less than about 0.5 times/minutes;and the method of the present invention increases the rate of solvent removal from microspheres in in-water drying, reduces the amount of solvent in microspheres in a short time.
    Type: Grant
    Filed: September 16, 1998
    Date of Patent: March 14, 2000
    Assignee: Takeda Chemical Industries, Ltd.
    Inventors: Nobuyuki Takechi, Seiji Ohtani, Akihiro Nagai
  • Patent number: 6033888
    Abstract: Oxalate-degrading enzymes and bacteria were encapsulated for both enteric and intraperitoneal administration. We have shown that via alginate microencapsulation of Oxalobacter formigenes, enzymatic activity was retained for several months. A new process was developed which strengthened the aliginate microcapsules and their tolerance to citrate treatment. Much smaller (30-50 .mu.m) aliginate microcapsules were made for injection as means of impantation. For oral administration, multi-encapsulated microspheres of cellulose acetate phthalate in poly-2-vinylpyridine (pKa=3.5) were prepared to protect the enzymes from gastric juices.
    Type: Grant
    Filed: July 10, 1997
    Date of Patent: March 7, 2000
    Assignee: University of Florida
    Inventors: Chris Batich, Farid Vaghefi
  • Patent number: 6022500
    Abstract: A process is described for the enzyme catalyzed synthesis of polymeric microspheres from monomers such as ethylphenol, naphthols and hydroxypyrenes in reverse micelles in the presence of a detergent. Polymeric microspheres synthesized are porous with nonuniform densities. Polymers prepared from naphthols and hydroxypyrenes are fluorescent with electroluminescent properties. A number of materials such as enzymes, drugs and inorganic materials such as iron oxide and cadmium sulfide are encapsulated in the hollow polymeric microspheres synthesized. These encapsulations are carried out during or after the syntheses of the polymeric microspheres. Functional properties of the encapsulated materials such as enzyme, magnetic and nonlinear optical properties are demonstrated in the polymeric composites.
    Type: Grant
    Filed: September 25, 1996
    Date of Patent: February 8, 2000
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Vijay T John, Gary L McPherson, Joseph A Akkara, David L Kaplan
  • Patent number: 6020066
    Abstract: Novel microcapsules are characterized in that the walls thereof consist of reaction products of crosslinking agents with iminooxadiazinedione isocyanates or the walls thereof contain such reaction products. A process for the production of such microcapsules has also been found, as have carbonless copying papers containing such microcapsules.
    Type: Grant
    Filed: October 23, 1997
    Date of Patent: February 1, 2000
    Assignee: Bayer Aktiengesellschaft
    Inventors: Jurgen Weisser, Frank Richter, Carl-Gerd Dieris, Wolfgang Krohn
  • Patent number: 6019998
    Abstract: A membrane structure employing a structure in which a lipid membrane is held by a hydrophilic polymer. The hydrophilic polymer layer contains an aqueous phase. There are functional molecules distributed selectively throughout each layer. The membrane structure is adaptable to applications as a separating agent, filler or delivery agent by performing physical and chemical operations.
    Type: Grant
    Filed: March 26, 1997
    Date of Patent: February 1, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tsuyoshi Nomoto, Yasuko Tomida, Junji Ohyama, Tomoko Maruyama
  • Patent number: 6017584
    Abstract: Disclosed herein are novel electrophoretic displays and materials useful in fabricating such displays. In particular, novel encapsulated displays are disclosed. Particles encapsulated therein are dispersed within a suspending, or electrophoretic, fluid. This fluid may be a mixture of two or more fluids or may be a single fluid. The displays may further comprise particles dispersed in a suspending fluid, wherein the particles contain a liquid. In either case, the suspending fluid may have a density or refractive index substantially matched to that of the particles dispersed therein. Finally, also disclosed herein are electro-osmotic displays. These displays comprise at least one capsule containing either a cellulosic or gel-like internal phase and a liquid phase, or containing two or more immiscible fluids. Application of electric fields to any of the electrophoretic displays described herein affects an optical property of the display.
    Type: Grant
    Filed: August 27, 1998
    Date of Patent: January 25, 2000
    Assignee: E Ink Corporation
    Inventors: Jonathan D. Albert, Barrett Comiskey, Joseph M. Jacobson, Libing Zhang, Andrew Loxley, Robert Feeney, Paul Drzaic, Ian Morrison
  • Patent number: 6001312
    Abstract: The present invention provides a novel reactor for making capsules with uniform membrane. The reactor includes a source for providing a continuous flow of a first liquid through the reactor; a source for delivering a steady stream of drops of a second liquid to the entrance of the reactor; a main tube portion having at least one loop, and an exit opening, where the exit opening is at a height substantially equal to the entrance. In addition, a method for using the novel reactor is provided. This method involves providing a continuous stream of a first liquid; introducing uniformly-sized drops of the second liquid into the stream of the first liquid; allowing the drops to react in the stream for a pre-determined period of time; and collecting the capsules.
    Type: Grant
    Filed: April 16, 1997
    Date of Patent: December 14, 1999
    Inventors: Taylor G. Wang, Amrutur V. Anikumar, Igor Lacik
  • Patent number: 5997946
    Abstract: A new and novel solid, microencapsulated product comprising a microencapsulated material contained within a cast, water-soluble, film-forming polymer and the process for preparing such product is disclosed.
    Type: Grant
    Filed: May 7, 1998
    Date of Patent: December 7, 1999
    Assignee: Zeneca Limited
    Inventors: Gordon Alastair Bell, Rowena Roshanthi Landham
  • Patent number: 5993985
    Abstract: A method of manufacturing porous ceramic tubes for fuel cells with improved properties and higher manufacturing yield is disclosed. The method involves extruding a closed end fuel cell tube, such as an air electrode of a solid oxide fuel cell, in which the closed end also functions as the sintering support. The resultant fuel cell tube has a superior porosity distribution which allows improved diffusion of oxygen at the closed end of the tube during operation of the fuel cell. Because this region has the highest current density, performance enhancement and improved reliability of the fuel cell tube result. Furthermore, the higher manufacturing yield associated with the present method decreases the overall fuel cell cost.
    Type: Grant
    Filed: April 9, 1998
    Date of Patent: November 30, 1999
    Assignee: Siemens Westinghouse Power Corporation
    Inventor: Brian P. Borglum
  • Patent number: 5965109
    Abstract: The present invention relates to a process for making insoluble gas-filled, pressure-resistant microspheres containing a liquid or solid hydrophobic barrier within the microsphere shell, and products of this process. This barrier serves to decrease the rate of gas exchange between the microsphere and the aqueous environment surrounding the microsphere and thus enhances resistance to pressure due to gas exchange.
    Type: Grant
    Filed: November 17, 1997
    Date of Patent: October 12, 1999
    Assignee: Molecular Biosystems, Inc.
    Inventor: Rolf Lohrmann
  • Patent number: 5952079
    Abstract: The present invention discloses a ceramic honeycomb structure comprising partition walls 3 that form mutually adjacent flow paths having a polygonal cross-section, and a peripheral wall 5 provided around the circumference of partition walls that hold the partition walls integrated into a single unit; wherein, the mean thickness of partition walls 3 is 0.05 mm to 0.13 mm, the mean thickness of peripheral wall 5 is greater than the mean thickness of partition walls 3, and the mean contact width between partition walls 3 and peripheral wall 5 satisfies a predetermined relationship. This ceramic honeycomb structure is able to inhibit the occurrence of chipping in the vicinity of the peripheral wall.
    Type: Grant
    Filed: September 4, 1998
    Date of Patent: September 14, 1999
    Assignee: Denso Corporation
    Inventors: Yosiyasu Andou, Yasunao Miura, Kazuyuki Ito
  • Patent number: 5932152
    Abstract: Suspension polymers having high swellability have low contents of soluble fractions if aliphatic peroxy esters are used as polymerization initiators.
    Type: Grant
    Filed: April 6, 1998
    Date of Patent: August 3, 1999
    Assignee: Bayer Aktiengesellschaft
    Inventors: Wolfgang Podszun, Olaf Halle, Werner Struver, Robert Bloodworth, Holger Lutjens
  • Patent number: 5932285
    Abstract: Methods and compositions for encapsulated polymeric gels swollen with nonaqueous reactive materials are provided. The methods include gel synthesis, swelling of a gel precursor with a first nonaqueous reactive material, and encapsulation of the swollen gel with a second nonaqueous reactive material. Gels precursors may be synthesized from crosslinking polymers, or alternatively, may be formed by crosslinking and polymerizing a monomer starting material. An accelerator may be utilized to facilitate swelling of the gel precursor with the first nonaqueous reactive material. Foams and composites may also be swollen with the first nonaqueous reactive material. The swollen gel is then contacted with a second nonaqueous reactive material such that an encapsulation layer is formed thereby. The encapsulated gels may be stored for subsequent use.
    Type: Grant
    Filed: February 17, 1995
    Date of Patent: August 3, 1999
    Assignee: MedLogic Global Corporation
    Inventors: E. C. Lupton, Xiaohong Yu, Lev Bromberg, Barry Joseph Hand
  • Patent number: 5925464
    Abstract: Microencapsulated compositions, useful, for example, as pesticidal formulations, were prepared a process in which the microcapsules containing the encapsulated material are formed in an interfacial polycondensation reaction carried out in the presence of one polyvinylalcohol, a different polyvinylalcohol is added, and the resulting mixture is spray dried.
    Type: Grant
    Filed: August 8, 1997
    Date of Patent: July 20, 1999
    Assignee: Dow AgroSciences LLC
    Inventors: Patrick Joseph Mulqueen, Geoff Smith, Steven D. Lubetkin
  • Patent number: 5919407
    Abstract: A microencapsulated adhesive and a method for producing that microencapsulated adhesive are disclosed. The adhesive is produced from a solvent-based adhesive composition such as a styrene butadiene rubber composition or an acrylic. The solvent-based adhesive composition may be encapsulated by interfacial polymerization, gelatin/gum arabic coacervation or melamine/formaldehyde encapsulation. The solvent is removed from the microcapsules by heating or reduced pressure to form an adhesive that is non-tacky, but becomes tacky upon application of external forces, such as shearing. The microencapsulated adhesive composition may be used, among other applications, as an adhesive for stamps or envelopes.
    Type: Grant
    Filed: December 28, 1992
    Date of Patent: July 6, 1999
    Assignee: Moore Business Forms, Inc.
    Inventor: Hung Ya Chao
  • Patent number: 5916598
    Abstract: A method for preparing biodegradable, biocompatible microparticles. A first phase is prepared that includes a biodegradable, biocompatible polymer, an active agent, and a solvent. An immiscible second phase is prepared. The first and second phases are combined to form an emulsion in which the first phase is discontinuous and the second phase is continuous. The two phases are immersed in a quench liquid that includes a quench medium and a quantity of the solvent. The quantity of the solvent is selected to control a rate of extraction of the solvent from the first phase. The first phase is isolated in the form of microparticles. Also disclosed is a microencapsulated active agent prepared by the method for preparing biodegradable, biocompatible microparticles.
    Type: Grant
    Filed: May 4, 1998
    Date of Patent: June 29, 1999
    Assignee: Alkermes Controlled Therapeutics Inc. II
    Inventors: Michael E. Rickey, J. Michael Ramstack, Danny H. Lewis
  • Patent number: 5916680
    Abstract: A thermo-responsive microcapsule containing a diazo compound or an electron donative dye precursor, wherein the capsule wall of the microcapsule is composed of at least one polymer obtained by polymerization of an isocyanate compound containing an adduct of (A) a compound having one active hydrogen in the molecule and having an average molecular weight from 500 to 20000 and (B) a multifunctional isocyanate having two or more isocyanate groups in the molecule, and a heat-sensitive recording material and a multicolor heat-sensitive recording material comprising a heat-sensitive recording layer containing the microcapsule are disclosed.
    Type: Grant
    Filed: October 6, 1997
    Date of Patent: June 29, 1999
    Assignee: Fuji Photo Film Co., Ltd
    Inventors: Yuichi Wakata, Kimio Ichikawa
  • Patent number: 5910314
    Abstract: The present invention provides a process for the preparation of microcapsule compositions, methods for using those microcapsule compositions, compositions containing those microcapsule compositions and microcapsules prepared by the process of the present invention.
    Type: Grant
    Filed: October 7, 1997
    Date of Patent: June 8, 1999
    Assignee: American Cyanamid Company
    Inventors: Brian Eric Benoff, Robin William Dexter
  • Patent number: 5884138
    Abstract: An improvement in a method of extruding a plasticized inorganic powder mixture having a plasticizing organic binder carried in an aqueous vehicle, by passing the mixture through an extruder and then through a die to produce an extrudate. The improvement involves homogeneously blending in the extruder as part of the mixture, carbon dioxide in the supercritical and/or liquid form, to lower the viscosity of the mixture and produce an extrudate that is stiffer in a shorter time than it would be, absent the carbon dioxide, without increasing the extrusion pressure.
    Type: Grant
    Filed: June 4, 1997
    Date of Patent: March 16, 1999
    Assignee: Corning Incorporated
    Inventors: Devi Chalasani, Ronald E. Johnson, Christopher J. Malarkey
  • Patent number: 5876754
    Abstract: The invention relates to accurately meterable shaped articles, for example granules or pellets, containing hydrophilic macromolecules, active compounds and optionally further pharmaceutically acceptable structure-forming substances and auxiliaries, the active compound being present in a matrix in dissolved, suspended or emulsified form, and a novel process for the production of these shaped articles, the process being particularly economically and ecologically acceptable, and use of the shaped articles as medicaments, in which the bioavailability, shelf life and tolerability is increased. Using the shaped articles or mixtures according to the invention, intermediates or final products for pharmacy, cosmetics, diagnosis, analysis or dietetics (healthcare) can additionally be advantageously prepared.
    Type: Grant
    Filed: December 19, 1994
    Date of Patent: March 2, 1999
    Assignee: Alfatec-Pharma GmbH
    Inventors: Jens-Christian Wunderlich, Ursula Schick, Jurgen Werry, Jurgen Freidenreich
  • Patent number: 5871722
    Abstract: Ionic compositions comprise an active ingredient absorbed within a network of internal pores defined by a plurality of polymeric particles. The particles are preferably crosslinked polymeric beads having a diameter in the range from about 5 to 100 microns and a surface charge density from about 0.1 to 10 meq/qm hydrogen ion capacity. The active ingredients are released from the ionic polymer beads over time when orally administered, applied to a keratinic material, typically human skin or hair or otherwise delivered to a target environment. The use of a cationic charge promotes adhesion of the beads to the keratinic material.
    Type: Grant
    Filed: April 11, 1995
    Date of Patent: February 16, 1999
    Assignee: Advanced Polymer Systems, Inc.
    Inventors: Sergio Nacht, Richard Won, Martin A. Katz, Tai Cheng, Christine J.Y. Liau, Robert P. Eury, Michael Froix
  • Patent number: 5866155
    Abstract: Methods for producing matrices useful in bone graft onlay and inlay procedures are provided. Compositions prepared by these methods are also provided.
    Type: Grant
    Filed: November 20, 1996
    Date of Patent: February 2, 1999
    Assignee: Allegheny Health, Education and Research Foundation
    Inventors: Cato Laurencin, Mark Borden
  • Patent number: 5863862
    Abstract: The invention relates to a process for the preparation of microcapsulated flakes or powders by drying aqueous mixtures containing (a) one or more water-emulsifiable, non-thermoplastic compounds which have a higher boiling point than waterand (b) at least one water-soluble, film-forming polymer, in which the content of component (a) is up to about 95% by weight, based on the dry weight of components (a) and (b), with the proviso that the water-soluble, film-forming polymer has a flocculation point of from 20.degree. to 98.degree. C. or the flocculation point is adjusted to from 20.degree. to 98.degree. C. with the aid of additives, and drying is carried out by thin-layer drying in a temperature range above the flocculation point.
    Type: Grant
    Filed: November 15, 1996
    Date of Patent: January 26, 1999
    Assignee: Wacker-Chemie GmbH
    Inventors: Herbert Eck, Heinrich Hopf, Gerald Fleischmann, Ernst Innertsberger, Jakob Schmidlkofer
  • Patent number: 5855826
    Abstract: Disclosed herein is a double capsule for cosmetics obtained by matrix-double-encapsulation method which comprises steps of (a) first-encapsulating the fat-soluble active matrials with filming materials to give a microcapsule; (b) encapsulating the microcapsule of the step (a) with gellan gums, and a cosmetic composition containing the same.
    Type: Grant
    Filed: December 18, 1996
    Date of Patent: January 5, 1999
    Assignee: Pacific Corporation
    Inventors: Chung Nam Lee, Ok Sob Lee, Hak Hae Kang, Dong Soon Park
  • Patent number: 5851451
    Abstract: Disclosed is a method of producing microspheres which comprises subjecting a w/o/w emulsion or o/w emulsion to an in-water drying method under the following conditions:1) the amount of microspheres per m.sup.3 of an external aqueous phase is about 0.1 to about 500 kg,2) the square root of the area (unit: m.sup.2) of the liquid surface in contact with the gas phase is about 0.2 to about 4.5 per the cube root of the volume (unit: m.sup.3) of an external aqueous phase,3) the w/o/w emulsion or o/w emulsion is replaced at the replacement frequency of about 0.01 to about 10 times/minutes,4) a gas is blown to the w/o/w emulsion or o/w emulsion at the gas transfer rate near the liquid surface of about 0.1 to about 300 m/second, and5) the gas is replaced at the replacement frequency of not less than about 0.5 times/minutes;and the method of the present invention increases the rate of solvent removal from microspheres in in-water drying, reduces the amount of solvent in microspheres in a short time.
    Type: Grant
    Filed: December 13, 1996
    Date of Patent: December 22, 1998
    Assignee: Takeda Chemical Industries, Ltd.
    Inventors: Nobuyuki Takechi, Seiji Ohtani, Akihiro Nagai
  • Patent number: 5827531
    Abstract: Methods of forming multi-lamellar microcapsules having alternating layers of hydrophilic and hydrophobic immiscible liquid phases have been developed using different polymer/solvent systems. The methods use liquid-liquid diffusion and simultaneous lateral phase separation, controlled by proper timed-sequence exposures of immiscible phases and low shear mixing, to form narrow size distributions of spherical, multilamellar microcapsules. The use of special formulations of solubilized drugs, surfactants, and polymeric co-surfactants in aqueous vehicles which are dispersed in hydrocarbon solvents containing small quantities of oil, low molecular weight co-surfactants and glycerides that are aqueous insoluble enables the formation of unique microcapsules which can carry large amounts of pharmaceuticals in both aqueous and non-aqueous solvent compartments.
    Type: Grant
    Filed: December 2, 1994
    Date of Patent: October 27, 1998
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Dennis R. Morrison, Benjamin Mosier
  • Patent number: 5753152
    Abstract: The present invention relates to a process for preparing matrix capsules having hydrocarbon cores sufficiently large to contain large size particle actives which process comprises dispersing actives in hydrocarbon core material, and dispersing the active containing hydrocarbon in a polymer solution to form a polymer matrix emulsion of drops of said core material in said solution. The key to the invention is to obtain the dispersion by utilizing low shear rates previously uncontemplated using the standard shearing machinery of the art. This in turn is accomplished by maintaining the core within defined rheological parameters. By using lower shear rates, applicants were unexpectedly able to prepare capsules capable of stably incorporating large size actives in the core.
    Type: Grant
    Filed: September 6, 1995
    Date of Patent: May 19, 1998
    Assignee: Lever Brothers Company, Division of Conopco, Inc.
    Inventor: Tirucherai Varahan Vasudevan
  • Patent number: 5741591
    Abstract: A encapsulation method applicable to pharmaceutical preparations, cosmetics, pigment imparting materials such as inks, paints, dyes, electrostatic toner, and others is disclosed, as are methods of use thereof. According to the disclosed method, the use of auxiliary materials such as emulsifiers or surfactants can be dispensed with, and ultramicrocapsules having a readily controllable diameter of 1 .mu.m and less can be produced. The disclosed method includes the steps of preparing an organic phase consisting of a mixture of one or more hydrophobic liquid and/or solid materials and self dispersable resin which through the action of an aqueous phase, self disperses into particles with a diameter of 0.1 .mu.m and less; combining an aqueous phase with the organic phase, whereby self emulsification takes place, thereby encapsulating the one or more hydrophobic liquid and/or solid materials.
    Type: Grant
    Filed: October 17, 1995
    Date of Patent: April 21, 1998
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Nansei Tashiro, Osamu Maruyama
  • Patent number: 5730912
    Abstract: The invention is directed to a method for the encapsulation of liquids within a continuous impervious coating of thermoplastic material. The method is carried out with continuous agitation during which the adsorbent and adsorbate are coated with a plurality of sprayed layers of thermoplastic coating material while maintaining the adsorbent in free-flowing powder consistency during the coating steps. The method is especially advantageous for the encapsulation of volatile liquids.
    Type: Grant
    Filed: May 30, 1996
    Date of Patent: March 24, 1998
    Assignee: M-Cap Technologies International
    Inventors: Randall Vann Redd, Joseph L. Sell
  • Patent number: 5720976
    Abstract: The present invention provides a thermosensitive liposome which permits temperature-sensitive drug release and exhibits variable release temperatures. The process for preparing a thermosensitive liposome of the invention, comprises a step of coating the surface of a liposome with a copolymer of N-isopropylacrylamide/octadecylacrylate/acrylic acid, by the addition of the copolymer to the liposome suspension in a weight ratio of 1:0.05 to 1:0.2 (liposome:copolymer), and the incubation of the polymer-liposome suspension at a temperature range of 0.degree. to 10.degree. C., for 10 to 14 hours. The thermosensitive liposome of the present invention is able to control the temperature of drug release at a temperature range of above 28.degree. C., preferably at 28.degree. to 36.degree. C., depending on the acrylic acid content in the copolymer of N-isopropylacrylamide/octadecylacrylate/acrylic acid.
    Type: Grant
    Filed: January 14, 1997
    Date of Patent: February 24, 1998
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Jong-Duk Kim, Jin-Chul Kim, Soo-Kyoung Bae
  • Patent number: 5718922
    Abstract: A method of forming microspheres containing a hydrophilic drug or agent for injection to provide localized treatment over a protracted time with sustained delivery in a therapeutically indicated rate band. The drug or agent is first dispersed or suspended as a micropulverized solid in an inert hydrophobic oil and sonicated with a non-aqueous solution of a biodegradable polymer. The dispersion is then stabilized in a second oil to remove solvent from the microspheres. Non-aqueous solvents are used throughout, and high drug concentrations are obtained simultaneously with enhanced control over a uniform and sustained delivery rate with extended duration of delivery. In vitro studies of ganciclovir in a silicone oil/fluorosilicone oil/PLGA system yield microsphere fractions that provide dose levels in a therapeutic range for CMV retinitis from only a single intravitreal injection that lasts substantially in excess of one month. The preparation method allows drug loading efficiencies above ninety percent.
    Type: Grant
    Filed: May 31, 1995
    Date of Patent: February 17, 1998
    Assignee: Schepens Eye Research Institute, Inc.
    Inventors: Rocio Herrero-Vanrell, Miguel F. Refojo
  • Patent number: 5716640
    Abstract: A method of producing sustained-release microcapsules containing a biologically active substance from an W/O emulsion comprising an inner aqueous phase containing said biologically active substance and an external oil phase containing a biodegradable polymer, characterized in that microcapsules formed on microencapsulation of said biologically active substance with said biodegradable polymer are heated at a temperature not lower than the glass transition temperature of said biodegradable polymer but not so high as to cause aggregation of the microcapsules. This method enables the production of very useful sustained release microcapsules adapted to release a bologically active substance at a calculated rate over a protracted time period starting immediately following administration without an initial burst within one day following administration.
    Type: Grant
    Filed: August 29, 1996
    Date of Patent: February 10, 1998
    Assignee: Takeda Chemical Industries, Ltd.
    Inventors: Shigeru Kamei, Minoru Yamada, Yasuaki Ogawa
  • Patent number: 5709340
    Abstract: A microencapsulated adhesive and a method for producing that microencapsulated adhesive are disclosed. The adhesive is produced from a solvent-based adhesive composition such as a styrene butadiene rubber composition an acrylic. The solvent-based adhesive composition may be encapsulated by interfacial polymerization, gelatin/gum arabic coacervation or melamine/formaldehyde encapsulation. The solvent is removed from the microcapsules by heating or reduced pressure to form an adhesive that is non-tacky, but becomes tacky upon application of external forces, such as shearing. The microencapsulated adhesive composition may be used, among other applications, as an adhesive for stamps or envelopes.
    Type: Grant
    Filed: August 18, 1995
    Date of Patent: January 20, 1998
    Assignee: Moore Business Forms, Inc.
    Inventor: Hung Ya Chao
  • Patent number: 5705174
    Abstract: The present invention provides a process for the preparation of microcapsule compositions, methods for using those microcapsule compositions, compositions containing those microcapsule compositions and microcapsules prepared by the process of the present invention.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: January 6, 1998
    Assignee: American Cyanamid Company
    Inventors: Brian Eric Benoff, Robin William Dexter
  • Patent number: 5700486
    Abstract: Pharmaceutical compositions in the form of particles comprising a biodegradable polymer and/or a polysaccharide jellifying and/or bioadhesive polymer, an amphiphilic polymer, an agent modifying the interface properties of the particles and a pharmacologically active substance. Said compositions exhibit improved biocompatibility features and allow a controlled release of the active substance.
    Type: Grant
    Filed: April 30, 1996
    Date of Patent: December 23, 1997
    Assignee: Vectorpharma International S.p.A.
    Inventors: Tiziana Canal, Mara Lucia Lovrecich, Fabio Carli
  • Patent number: 5691060
    Abstract: The invention relates to microparticles, particularly microcapsules and their fabrication method. Said microparticles, and particularly said microcapsules, are characterized in that they have a wall made of the product obtained from the reaction between a polysaccharide carrying esterified carboxylic groups and a polyaminated or polyhydroxylated substance, particularly through a transacylation reaction. Said microparticles or said microcapsules are useful for the fabrication of cosmetic, pharmaceutical or food product compositions.
    Type: Grant
    Filed: February 21, 1995
    Date of Patent: November 25, 1997
    Assignee: Coletica
    Inventor: Marie-Christine Levy
  • Patent number: 5667806
    Abstract: Methods for preparing microspheres are provided. A carrier vehicle and a precipitator are nebulized and contacted. Alternatively, a carrier is nebulized in an aqueous acid and the concentration of the acid is decreased. Apparatus are also provided.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: September 16, 1997
    Assignee: Emisphere Technologies, Inc.
    Inventor: Martin L. Kantor
  • Patent number: 5662916
    Abstract: The invention relates to a novel formulation of per se known pesticides in the form of microcapsules, to a process for the preparation of microcapsules and to the use of said microcapsules for controlling weeds, plant diseases, insects and representatives of the order Acarina.
    Type: Grant
    Filed: May 26, 1995
    Date of Patent: September 2, 1997
    Assignee: Ciba-Geigy Corporation
    Inventors: Rudolf Nastke, Andreas Leonhardt, Ernst Neuenschwander
  • Patent number: 5653922
    Abstract: The present invention relates to porous crosslinked polymeric microbeads having cavities joined by interconnecting pores wherein at least some of the cavities at the interior of each microbead communicate with the surface of the microbead. The present invention also relates to a process for producing a porous, crosslinked polymeric microbead as well as the product of this process. This process involves combining an oil phase with an aqueous discontinuous phase to form an emulsion, adding the emulsion to an aqueous suspension medium to form an oil-in-water suspension of dispersed emulsion droplets, and polymerizing the emulsion droplets to form microbeads. At least 10% of the microbeads produced in accordance with the present invention are substantially spherical or substantially ellipsoidal or a combination of the two.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: August 5, 1997
    Assignee: Biopore Corporation
    Inventors: Nai-Hong Li, James R. Benson, Naotaka Kitagawa
  • Patent number: 5648095
    Abstract: Hollow microcapsules or solid microspheres for use in diagnostic procedures, as well as methods for making the microcapsules, are provided, which are formed by combining a volatile oil with an aqueous phase including a water soluble material such as a starch, modified starch or proteinaceous material, or a polyethylene glycol (PEG) conjugate, to form a primary emulsion. The primary emulsion then is combined with a second oil, to form a secondary emulsion, and the material is permitted to harden and to form microcapsules around a liquid core of the volatile oil. At least part of the volatile oil then may be removed by evaporation to produce hollow microcapsules. Optionally, all of the volatile oil may be removed prior to hardening of the material, which produces solid microspheres. The The microcapsules can be used in a variety of applications for diagnostic purposes and for drug delivery.
    Type: Grant
    Filed: July 8, 1994
    Date of Patent: July 15, 1997
    Assignee: Danbiosyst UK Limited
    Inventors: Lisbeth Illum, Olufunmiloyo Lilly Johnson
  • Patent number: 5648099
    Abstract: Oxalate-degrading enzymes and bacteria were encapsulated for both enteric and intraperitoneal administration. We have shown that via alginate microencapsulation of Oxalobacter formigenes, enzymatic activity was retained for several months. A new process was developed which strengthened the alginate microcapsules and their tolerance to citrate treatment. Much smaller (30-50 .mu.m) alginate microcapsules were made for injection as means of implantation. For oral administration, multi-encapsulated microspheres of cellulose acetate phthalate in poly-2-vinylpyridine (pKa=3.5) were prepared to protect the enzymes from gastric juices.
    Type: Grant
    Filed: February 3, 1994
    Date of Patent: July 15, 1997
    Assignee: University of Florida
    Inventors: Chris Batich, Farid Vaghefi
  • Patent number: 5635211
    Abstract: Novel microcapsules are characterized in that their walls are made of reaction products of guanidine compounds and polyisocyanates or contain such reaction products. Dispersions containing such microcapsules can be prepared by replacing the amines, amino alcohols or hydrazine compounds in processes known per se for preparing microcapsule dispersions from polyisocyanates and amines, amino alcohols or hydrazine compounds by guanidine compounds. The present invention also relates to no-carbon copy papers containing dyestuff precursors in microcapsules whose walls are made of reaction products of guanidine compounds and polyisocyanates or contain such reaction products.
    Type: Grant
    Filed: February 21, 1995
    Date of Patent: June 3, 1997
    Assignee: Bayer Aktiengesellschaft
    Inventors: Ulrich Nehen, Jurgen Weisser
  • Patent number: 5635609
    Abstract: Particles, preparation methods therefor, and compositions containing same. The particles include at least one esterified polysaccharide and at least one polyamine, as well as at least one gellable polysaccharide when neither the esterified polysaccharide nor the polyamine can be gelled under the selected operating conditions. Said particle includes, at least on its surface, a membrane consisting of the product of the transacylation reaction between the esterified polysaccharide and said polyamine within an optionally gellable gel, said reaction causing the formation of covalent amide bonds. Such particles may be used to encapsulated various active principles useful in the fields of cosmetics, pharmaceuticals and agri-foodstuffs, enzymes, cells and micro-organisms.
    Type: Grant
    Filed: July 20, 1995
    Date of Patent: June 3, 1997
    Assignee: Coletica
    Inventors: Marie-Christine Levy, Florence Edwards-Levy, Isabelle Orly
  • Patent number: 5631018
    Abstract: A lipid-polymer conjugate for use in forming long-circulating liposomes is disclosed. The conjugate includes a vesicle-forming lipid having covalently attached to its polar head group, one of the polymers: polyvinylpyrrolidone, polyvinylmethylether, polyhydroxypropyl methacrylate, polyhydroxypropylmethacrylamide, polyhydroxyethyl acrylate, polymethacrylamide, polydimethylacrylamide, polymethyloxazoline, polyethyloxazoline, polyhydroxyethyloxazoline, polyhydroxypropyloxazoline, or polyaspartamide. A method for preparing liposomes containing the lipid-polymer conjugate is also disclosed.
    Type: Grant
    Filed: October 4, 1994
    Date of Patent: May 20, 1997
    Assignee: Sequus Pharmaceuticals, Inc.
    Inventors: Samuel Zalipsky, Martin C. Woodle, Danilo D. Lasic, Francis J. Martin
  • Patent number: 5622712
    Abstract: This invention relates to compounds of the formula ##STR1## or an optical isomer thereof wherein R.sup.1 and R.sup.2 are the same or different and are an alkyl or alkenyl group of 6 to 24 carbon atoms; R.sup.3, R.sup.4, R.sup.5 are the same or different and are alkyl of 1 to 8 carbon atoms, aryl, aralkyl of 7 to 11 carbon atoms, or when two or three of R.sup.3, R.sup.4, and R.sup.5 are taken together to form quinuclidino, piperidino, pyrrolidino, or morpholino; n is 1 to 8; and X is a pharmaceutically acceptable anion.
    Type: Grant
    Filed: May 4, 1994
    Date of Patent: April 22, 1997
    Assignee: Syntex (U.S.A.) Inc.
    Inventors: Deborah A. Eppstein, Philip L. Felgner, Thomas R. Gadek, Gordon H. Jones, Richard B. Roman
  • Patent number: 5622723
    Abstract: An improvement in the process of coacervation of chlorpheniramine maleate is provided whereby a predetermined amount of chlorpheniramine maleate charged to the process is maintained in the microcapsules by pre-saturating the coacervation medium with chlorpheniramine maleate.
    Type: Grant
    Filed: February 3, 1995
    Date of Patent: April 22, 1997
    Assignee: Eurand America, Incorporated
    Inventors: Marie J. Bettman, Sambasiva R. Ghanta
  • Patent number: 5603961
    Abstract: Sustained release multi-core microsphere preparation which shows high incorporation efficiency of medicament and can release the medicament at a specific rate, which comprises two or more biodegradable polymers and a pharmaceutically active ingredient, and has the medicament incorporated into microregions which are produced by one of these polymers (the first polymer), and these microregions are distributed in other biodegradable polymers (the second polymer), or a method for producing the same.
    Type: Grant
    Filed: September 30, 1993
    Date of Patent: February 18, 1997
    Assignee: Tanabe Seiyaku Co., Ltd.
    Inventors: Takehiko Suzuki, Yukiko Nishioka, Yasuhisa Matsukawa, Akihiro Matsumoto, Masao Kobayashi