To provide a hollow-fiber membrane maintaining properties as a separation membrane and durability in its use by suppressing the bias (thickness deviation) to 0.65 or less in a ratio between the maximum part and the minimum part in a wall thickness and by suppressing the variation of an inner diameter in a vertical direction to 10% or less.
In the method for manufacturing a hollow-fiber-type separation membrane in which a spinning solution is discharged from the outer annular part of a dual-pipe-shaped nozzle, while at the same time an in-hollow liquid is discharged from a center hole, and then is immersed into a solidification bath after passing through a free-running portion, the dual-pipe-shaped nozzle is so designed that the diameter of the center hole is 0.9 or less times the inner diameter of the hollow-fiber-type separation membrane and that the width of the outer annular part is 5 or more times the membrane thickness of the hollow-fiber-type separation membrane.
YAMAMOTO ISAMU
KATO MASAHIRO
| JP2005144412A | 2005-06-09 | |||
| JP2005342415A | 2005-12-15 | |||
| JPS57133211A | 1982-08-17 | |||
| JPS62162009A | 1987-07-17 |
| WO1996035504A1 | 1996-11-14 |
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