04250138 is referenced by 40 patents and cites 5 patents.

Polytetrafluoroethylene resin tubes having small pore size and high porosity are produced by a process which includes stretching the tubes by drawing using a metal die and a metal plug. By using the die and plug, the stress necessary for stretching is converted to a compressive force in the thickness direction of the tube. This compressive force is an essential factor in producing the microporous structure of the tubes. In addition, when stretching is performed by drawing, a ratio of thickness to inside diameter of the tube of 0.07 or less can be easily achieved.

Title
Process for producing microporous tubes of polytetrafluoroethylene
Application Number
832267
Publication Number
4250138
Application Date
May 23, 1979
Publication Date
February 10, 1981
Inventor
Koichi Okita
Osaka
JP
Agent
Sughrue Rothwell Mion Zinn and Macpeak
Assignee
Sumitomo Electric
JP
IPC
B29D 27/08
B29D 23/01
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