Patents by Inventor Cheng-Kung Liu

Cheng-Kung Liu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Method of suturing using a polyetherimide ester suture
    Patent number: 5480411
    Abstract: A method for suturing a wound using a suture manufactured from polyamide ester having the reaction product of at least one molecular weight diols; at least one dicarboxylic acids and at least one polyoxyalkylene diimide diacid to create a wound closure.
    Type: Grant
    Filed: February 27, 1995
    Date of Patent: January 2, 1996
    Assignee: United States Surgical Corporation
    Inventors: Cheng-Kung Liu, John C. Brewer
  • Method for improving the in vivo strength retention of a bioabsorbable implantable medical device and resulting medical device
    Patent number: 5478355
    Abstract: A method is provided for improving the in vivo strength retention of a bioabsorbable implantable medical device such as a suture.
    Type: Grant
    Filed: December 30, 1994
    Date of Patent: December 26, 1995
    Assignee: United States Surgical Corporation
    Inventors: Ross R. Muth, Nagabhushanam Totakura, Cheng-Kung Liu
  • Process of treating filaments
    Patent number: 5466406
    Abstract: A spin finish is applied to one or more as spun filaments. The spin finish, which can be a solution of glycerin in a solvent, can be easily removed from the filaments if desired by a water wash. Preferably, the spin finish is non-toxic and the filaments treated therewith are useful in forming surgical devices.
    Type: Grant
    Filed: June 7, 1994
    Date of Patent: November 14, 1995
    Assignee: United States Surgical Corporation
    Inventor: Cheng-Kung Liu
  • Monofilament suture and process for its manufacture
    Patent number: 5456696
    Abstract: A process and apparatus are provided for preparing monofilament sutures of improved physical characteristics.
    Type: Grant
    Filed: July 20, 1993
    Date of Patent: October 10, 1995
    Assignee: United States Surgical Corporation
    Inventor: Cheng-Kung Liu
  • Absorbable block copolymers and surgical articles fabricated therefrom
    Patent number: 5431679
    Abstract: Block copolymers wherein one of the blocks is made from hard phase forming monomers and another of the blocks is made from soft phase forming monomers copolymerized with randomly intermingled units of other soft phase forming monomers. The copolymers are useful in forming surgical articles, including both monofilament and multifilament sutures.
    Type: Grant
    Filed: March 10, 1994
    Date of Patent: July 11, 1995
    Assignee: United States Surgical Corporation
    Inventors: Steven L. Bennett, Cheng-Kung Liu
  • Bioabsorbable melt spun fiber based on glycolide-containing copolymer
    Patent number: 5425984
    Abstract: A bioabsorbable fiber useful for the manufacture of medical devices is obtained from a polymer containing from about 15 to about 30 mole percent glycolide in a melt spinning operation carried out under low shear conditions. The fiber is drawn at a ratio of about 1.5 to 2.7. The fiber possesses excellent tensile strength and a high level of retention of its original strength on storage.
    Type: Grant
    Filed: June 9, 1993
    Date of Patent: June 20, 1995
    Assignee: United States Surgical Corporation
    Inventors: John Kennedy, Cheng-Kung Liu
  • Polyamide monofilament suture
    Patent number: 5405358
    Abstract: A polyamide monofilament suture of reduced energy and/or increased knot security is prepared by extruding a monofilament from polyamide resin, stretching the monofilament and annealing the stretched monofilament.
    Type: Grant
    Filed: August 4, 1993
    Date of Patent: April 11, 1995
    Assignee: United States Surgical Corporation
    Inventors: Cheng-Kung Liu, John C. Brewer
  • Absorbable block copolymers and surgical articles fabricated therefrom
    Patent number: 5403347
    Abstract: Block copolymers wherein one of the blocks is made from hard phase forming monomers and another of the blocks is made from soft phase forming monomers copolymerized with randomly intermingled units of other soft phase forming monomers. The copolymers are useful in forming surgical articles, including both monofilament and multifilament sutures. The block copolymer preferably comprising:a) a proportion of glycolic acid ester units as end blocks, andb) a center block comprising 1,4 dioxan-2-one randomly polymerized with 1,3 dioxane-2-one.
    Type: Grant
    Filed: March 2, 1994
    Date of Patent: April 4, 1995
    Assignee: United States Surgical Corporation
    Inventors: Mark S. Roby, Steven L. Bennett, Cheng-Kung Liu
  • Polyamide monofilament suture manufactured from higher order polyamide
    Patent number: 5349044
    Abstract: A higher order polyamide monofilament suture exhibits improved properties such as greater resistance to creep, greater knot security and greater chemical stability in aqueous environments.
    Type: Grant
    Filed: September 24, 1993
    Date of Patent: September 20, 1994
    Assignee: United States Surgical Corporation
    Inventors: Cheng-Kung Liu, John C. Brewer
  • Absorbable block copolymers and surgical articles made therefrom
    Patent number: 5322925
    Abstract: Block copolymers have a first copolymer block wherein lactide is the predominant component and a second copolymer block wherein trimethylene carbonate is the predominant component. The copolymers are useful in forming surgical devices, including monofilament sutures.
    Type: Grant
    Filed: March 19, 1993
    Date of Patent: June 21, 1994
    Assignee: United States Surgical Corporation
    Inventors: Ross R. Muth, Nagabhushanam Totakura, Cheng-Kung Liu
  • Polypropylene multifilament warp knitted mesh and its use in surgery
    Patent number: 5292328
    Abstract: A surgical mesh of warp knit construction is fabricated from a polypropylene multifilament yarn.
    Type: Grant
    Filed: October 18, 1991
    Date of Patent: March 8, 1994
    Assignee: United States Surgical Corporation
    Inventors: Matthew E. Hain, Cheng-Kung Liu
  • Filament fabricated from a blend of ionomer resin and nonionic thermoplastic resin
    Patent number: 5284489
    Abstract: A filament is fabricated from a biologically acceptable blend of an ionomer resin such as an ionically crosslinked ethylene-methacrylic acid copolymer and a nonionic thermoplastic resin, e.g., a polyolefin such as an isotactic polypropylene.
    Type: Grant
    Filed: August 19, 1992
    Date of Patent: February 8, 1994
    Assignee: United States Surgical Corporation
    Inventors: Cheng-Kung Liu, John C. Brewer
  • Process for manufacture of polyamide monofilament suture
    Patent number: 5279783
    Abstract: A process for manufacturing polyamide monofilament suture includes the steps of extruding a polyamide resin, stretching the solidified monofilament and annealing the stretched monofilament so that it shrinks to within about 80 to about 97 percent of the length of the monofilament prior to annealing. The polyamide monofilament sutures so produced exhibit reduced energy compared to conventional polyamide monofilament sutures.
    Type: Grant
    Filed: January 30, 1992
    Date of Patent: January 18, 1994
    Assignee: United States Surgical Corporation
    Inventors: Cheng-Kung Liu, John C. Brewer
  • Suture fabricated from syndiotactic polypropylene
    Patent number: 5269807
    Abstract: A suture is manufactured from a syndiotactic polypropylene, advantageously by a melt extrusion (spinning) procedure. The suture exhibits greater flexibility than a comparable suture manufactured from isotactic polypropylene.
    Type: Grant
    Filed: August 27, 1992
    Date of Patent: December 14, 1993
    Assignee: United States Surgical Corporation
    Inventor: Cheng-Kung Liu
  • Absorbable polymers and surgical articles made therefrom
    Patent number: 5236444
    Abstract: Block copolymers have a first polymer block wherein glycolide is the predominant component and a second block having glycolide, lactide and trimethylene carbonate linkages. The copolymers are useful in forming surgical devices, including monofilament sutures.
    Type: Grant
    Filed: October 27, 1992
    Date of Patent: August 17, 1993
    Assignee: United States Surgical Corporation
    Inventors: Ross R. Muth, Nagabhushanam Totakura, Cheng-Kung Liu
  • Bioabsorbable melt spun fiber based on glycolide-containing copolymer
    Patent number: 5232648
    Abstract: A bioabsorbable fiber useful for the manufacture of medical devices is obtained from a polymer containing from about 15 to about 30 mole percent glycolide in a melt spinning operation carried out under low shear conditions. The fiber possesses excellent tensile strength and a high level of retention of its original strength on storage.
    Type: Grant
    Filed: July 19, 1991
    Date of Patent: August 3, 1993
    Assignee: United States Surgical Corporation
    Inventors: John Kennedy, Cheng-Kung Liu
  • Polyetherimide ester suture and its method of manufacture and method of use
    Patent number: 5225485
    Abstract: A polyetherimide suture exhibits excellent properties such as resistance to creep, great knot security and physical stability. The suture may be monofilament or multifilament, and methods of making and using the suture are disclosed.
    Type: Grant
    Filed: March 3, 1992
    Date of Patent: July 6, 1993
    Assignee: United States Surgical Corporation
    Inventors: Cheng-Kung Liu, John C. Brewer
  • Polypropylene monofilament suture and process for its manufacture
    Patent number: 5217485
    Abstract: A process is provided for manufacturing a polypropylene monofilament suture exhibiting reduced strain energy, increased knot security and greater resistance to acquiring an in-storage set.
    Type: Grant
    Filed: July 12, 1991
    Date of Patent: June 8, 1993
    Assignee: United States Surgical Corporation
    Inventors: Cheng-Kung Liu, John C. Brewer