Method for manufacture of hollow fiber
AssigneeTerumo Kabushiki Kaisha
InventorsJuuro Aoyagi, Kazuaki Takahara, Yukio Seita
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Abstract
A method for the manufacture of a hollow fiber which comprises extruding a cellulosic spinning dope through an annular spinning nozzle directly into a non-coagulative liquid layer in a bath filled in the upper layer with a coagulative liquid relative to said spinning dope and in the lower layer with a non-coagulative liquid of a halogenated hydrocarbon and, at the same time, introducing a non-coagulative liquid relative to said spinning dope into the inner center of the tubularly extruded thread of spinning dope, and subsequently passing the resultant tubular fiber of spinning dope through said coagulative liquid thereby coagulating and regenerating the fiber.
Claims20
A method of producing a hollow fiber having a substantially circular cross-section, said method comprising:
- (a) extruding a metal ammonia cellulose containing spinning dope through an annular spinning nozzle directly into a lower layer of a two-layer bath, said lower layer containing a first non-coagulating liquid selected from the group consisting of halogenated hydrocarbons and said bath further comprising an upper layer containing a coagulating liquid to thereby form a tubular extruded thread, wherein the height of the first non-coagulating liquid of the lower layer measured from the annular spinning nozzle to the interface of the first non-coagulating liquid and the upper layer is between 50 and 250 mm, and simultaneously introducing into the tubular hollow of said tubular extruded thread a second non-coagulating liquid;
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- (b) passing said tubular extruded thread containing said second non-coagulating liquid upwardly into and through said upper layer containing said coagulating liquid to thereby form said hollow fiber.
A method of producing a hollow fiber having a substantially circular cross-section having a diameter of between 50 and 500 .mu.m, said method comprising:
- (a) extruding a metal ammonia cellulose containing spinning dope through an annular spinning nozzle directly into a lower layer of a two-layer bath, said lower layer containing a first non-coagulating liquid having a specific gravity of at least 1.3 and selected from the group consisting of halogenated hydrocarbons, and said bath further comprising an upper layer containing a sodium hydroxide solution having a concentration of between 30 and 150 g/liter, wherein the height of the first non-coagulating liquid of the lower layer measured from the annular spinning nozzle to the interface of the non-coagulating liquid and the upper layer is between 50 and 250 mm, and simultaneously introducing into the tubular hollow of said tubular extruded thread a second non-coagulating liquid having a specific gravity of between 0.65 and 1.0;
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- (b) passing said tubular extruded thread containing said second non-coagulating liquid upwardly into and through said upper layer containing said sodium hydroxide solution to thereby form said hollow fiber.
Dependencies are inferred from the claim text.