Back to results
US 8,800,783 B2Granted
Polyamide hollow fiber membrane, and production method thereof
AssigneeUnitika Ltd.
InventorsHideto Matsuyama, Takahiro Ono, Satoshi Kawanaka, Kazuo Hirota
Life of this patent
Estimating the term…
Abstract
A hollow fiber membrane is produced through a thermally induced phase separation process by dissolving a highly hydrophilic polyamide resin in a high-boiling-point solvent such as an aprotic polar solvent at a temperature of not lower than 100° C. The hollow fiber membrane has a membrane surface having a water contact angle of not greater than 80 degrees, and has a water permeability of not less than 100 L/m2·atm·h and a 0.1-μm particle rejection percentage of not less than 90%.
Claims8
A polyamide hollow fiber membrane production method comprising:
- preparing a membrane formation dope solution by dissolving a polyamide resin in an organic solvent at a temperature of not lower than 100° C., the organic solvent having a boiling point of not lower than 150° C. and being insoluble with the polyamide resin at a temperature lower than 100° C.;
- extruding the membrane formation dope solution controlled at a temperature of not lower than 100° C. through a hollow fiber spinneret into a coagulation liquid kept at a temperature of lower than 100° C. to form a hollow fiber;
- and
- immersing the hollow fiber in another solvent to remove the organic solvent to form a hollow fiber membrane.
1 more element
Dependencies are inferred from the claim text.