1
Makoto Kodama, Tsukasa Sakai, Keishiro Tsuda, Koichi Okita, Shigeru Asako, Masaharu Komamiya, Hiroshi Oinuma: Antithrombogenic materials. Agency of Industrial Science and Technology, Sumitomo Electric, Watanabe Pharmaceutical, Sughrue Mion Zinn Macpeak & Seas, July 2, 1991: US05028597 (176 worldwide citation)

An antithrombogenic material is described, comprising an expanded polytetrafluoroethylene base having a collagen layer provided on the surface thereof, and further provided thereon a composite layer of collagen and a mucopolysaccharide, and said collagen is crosslinked with a crosslinking agent.


2
Koichi Okita: Vascular prostheses composed of polytetrafluoroethylene and process for their production. Sumitomo Electric, Sughrue Rothwell Mion Zinn and Macpeak, June 24, 1980: US04208745 (118 worldwide citation)

A vascular prosthesis comprising a tubing of porous polytetrafluoroethylene, the polytetrafluoroethylene tubing having a fibrous structure of nodes and fibers connecting the nodes together and having a structure in which the fibrous structure at the inside surface of the tubing is finer than the fib ...


3
Koichi Okita: Composite structure vascular prostheses. Sumitomo Electric, Sughrue Rothwell Mion Zinn and Macpeak, March 18, 1980: US04193138 (82 worldwide citation)

A composite structure vascular prosthesis comprising a porous polytetrafluoroethylene tube in which the pores of the porous polytetrafluoroethylene tube are filled with at least one water-insolubilized water-soluble polymer, and a process for producing the composite structure vascular prosthesis.


4
Koichi Okita, Shigeru Asako, Katsuya Yamada, Kazuhiro Okabe, Tohru Kashiwagi: Tubular prosthesis having a composite structure. Sumitomo Electric, Sughrue Mion Zinn Macpeak & Seas, April 18, 1989: US04822361 (73 worldwide citation)

A tubular prosthesis having a composite structure comprising (i) tubular polytetrafluoroethylene having a microfibrous structure comprising small nodes interconnected with fibrils and (ii) materials which can be absorbed by a living body wherein (a) said polytetrafluoroethylene has a greater average ...


5
Koichi Okita: Hydrophilic porous structures and process for production thereof. Sumitomo Electric, Sughrue Rothwell Mion Zinn and Macpeak, September 12, 1978: US04113912 (71 worldwide citation)

A hydrophilic porous structure comprising a porous fluorocarbon resin structure with the pores of the fluorocarbon resin structure containing at least one water-insolubilized water-soluble polymer and a process for the production thereof.


6
Koichi Okita: Porous polytetrafluoroethylene tubings and process of producing them. Sumitomo Electric, Sughrue Rothwell Mion Zinn and Macpeak, April 4, 1978: US04082893 (56 worldwide citation)

A porous polytetrafluoroethylene tubing, useful as artificial internal organs or industrial filtering materials for, for example reverse osmosis, ultrafilteration, etc., having a microporous fibrous structure in which the fibrous structure is composed of fibers and nodes connected with each other an ...


7
Koichi Okita: Asymmetric porous film materials and process for producing same. Sumitomo Electric, Sughrue Rothwell Mion Zinn and Macpeak, February 3, 1981: US04248924 (55 worldwide citation)

Porous film materials composed of polytetrafluoroethylene having an asymmetric structure are produced by stretching the film using a pair of revolving rolls which are heated to a temperature lower than the melting point of the film. Stretching is produced by revolving the two rolls at different spee ...


8
Koichi Okita: Production of asymmetric porous film materials. Sumitomo Electric, Sughrue Rothwell Mion Zinn and Macpeak, July 7, 1981: US04277429 (44 worldwide citation)

Porous film materials composed of polytetrafluoroethylene having an asymmetric structure are produced by stretching the film using a pair of revolving rolls which are heated to a temperature lower than the melting point of the film. Stretching is produced by revolving the two rolls at different spee ...


9
Koichi Okita: Process for producing porous polytetrafluoroethylene tubings. Sumitomo Electric, Sughrue Rothwell Mion Zinn and Macpeak, November 18, 1980: US04234535 (43 worldwide citation)

A porous polytetrafluoroethylene tubing, useful as artificial internal organs or industrial filtering materials for, for example reverse osmosis, ultrafilteration, etc., having a microporous fibrous structure in which the fibrous structure is composed of fibers and nodes connected with each other an ...


10
Koichi Okita: Extrusion process of polytetrafluoroethylene tubing materials and apparatus therefor. Sumitomo Electric, Sughrue Rothwell Mion Zinn and Macpeak, September 30, 1980: US04225547 (41 worldwide citation)

This application relates to a paste extrusion process using a ram type extruder wherein at least one, preferably both, of the die and mandrel of the extruder are rotated, in opposite directions when both are rotated. In preferred embodiments, the material being extruded is polytetrafluoroethylene, t ...