External-perfusion hollow-fiber membrade module and inkjet printer having said module

1. A external-perfusion hollow-fiber membrane module comprising:

a hollow-fiber membrane bundle including a plurality of hollow-fiber membranes; and

a casing that houses the hollow-fiber membrane bundle, wherein

the hollow-fiber membrane bundle has one end that is fixed to an inside of the casing by a potting portion in an open state,

the other end of the hollow-fiber membrane bundle is a free end, and

the external-perfusion hollow-fiber membrane module is configured to perform degassing on a gas contained in a liquid inside the casing, the gas being introduced into an inside from an outer surface of the hollow-fiber membrane.

2. The external-perfusion hollow-fiber membrane module according to claim 1 , wherein the hollow-fiber membrane is a composite membrane including a homogeneous layer with gas permeability and a porous support layer supporting the homogeneous layer.

3. The external-perfusion hollow-fiber membrane module according to claim 1 , wherein the hollow-fiber membrane has an outer diameter of 280 μm or less.

4. The external-perfusion hollow-fiber membrane module according to claim 1 , wherein the hollow-fiber membrane has fracture strength of 0.5 N/fil or more and has fracture elongation of 50% or more.

5. The external-perfusion hollow-fiber membrane module according to claim 1 , wherein the hollow-fiber membrane bundle has a filling rate of from 20 to 50% in a cross section of the casing.

6. The external-perfusion hollow-fiber membrane module according to claim 1 , wherein

the hollow-fiber membrane bundle in the casing has one end that is provided with a first port communicating with the inside of the casing to pass a liquid therethrough, and

the hollow-fiber membrane bundle in the casing has the other end side that is provided with a second port communicating with the inside of the casing to pass a liquid therethrough.

7. The external-perfusion hollow-fiber membrane module according to claim 6 , wherein

the first port is an outflow port having an outlet through which the liquid contained in the casing flows out, the outlet being disposed at a position spaced from a center of the casing,

the second port is an inflow port having an inlet through which a liquid flows into the casing, and

the external-perfusion hollow-fiber membrane module is configured such that a large quantity of liquid flowing into the casing through the inlet of the inflow port flow from a region opposite to a region, in which the outlet is formed, across the center of the casing, than the region in which the outlet is formed.

8. The external-perfusion hollow-fiber membrane module according to claim 7 , wherein

the inlet is disposed on a straight line extending in an extending direction of the hollow-fiber membrane bundle in which the hollow-fiber membrane bundle extends to the inside of the casing from the potting portion through the center of the casing,

the inside of the casing is disposed with a dispersion plate having openings through which the liquid flowing from the inlet passes, and

the dispersion plate is formed such that an opening area of the opening formed in the region opposite to the region, in which the outlet is formed, across the center of the casing is larger than an opening area of the opening formed in the region in which the outlet is formed.

9. The external-perfusion hollow-fiber membrane module according to claim 1 , further comprising:

a pipe member that communicates with the inside of the casing through an opening through which a liquid flows into the casing or the liquid contained in the casing flows out, wherein

the pipe member is installed to extend along an extending direction of the hollow-fiber membrane bundle in which the hollow-fiber membrane bundle extends to the inside of the casing from the potting portion through the center of the casing.

10. The external-perfusion hollow-fiber membrane module according to claim 9 , wherein the opening in the pipe member is formed on an outer peripheral surface of the pipe member.

11. The external-perfusion hollow-fiber membrane module according to claim 9 , wherein the opening in the pipe member is an inlet through which a liquid flows into the casing, and is opened toward one end of the hollow-fiber membrane bundle in the casing, and

the hollow-fiber membrane bundle in the casing has the other end side at which an outflow port is provided, the outflow port having an outlet through which a liquid contained in the casing flows out.

12. The external-perfusion hollow-fiber membrane module according to claim 11 , wherein the outlet of the outflow port is formed at a position not overlapping with a height position of the other end of the hollow-fiber membrane bundle in a direction perpendicular to an extending direction of the hollow-fiber membrane bundle in which the hollow-fiber membrane bundle extends to the inside of the casing from the potting portion.

13. The external-perfusion hollow-fiber membrane module according to claim 9 , wherein

the opening in the pipe member is an inlet through which a liquid flows into the casing,

the hollow-fiber membrane bundle in the casing has the other end side that is provided with a liquid introduction portion through which a liquid flows in along the hollow-fiber membrane bundle at an outside of the pipe member, and

the hollow-fiber membrane bundle in the casing has one end side that is provided with an outflow port having an outlet through which the liquid contained in the casing flows out.

14. The external-perfusion hollow-fiber membrane module according to claim 13 , wherein

the opening in the pipe member is formed on an outer peripheral surface of the pipe member, and a plurality of openings are formed in an axial direction of the pipe member, and

the openings are formed to have a smaller opening area at the one end side of the hollow-fiber membrane bundle compared to the opening area at the other end side thereof.

15. The external-perfusion hollow-fiber membrane module according to claim 14 , wherein the plurality of openings in the pipe member are formed side by side at predetermined intervals in the axial direction and the circumferential direction on the outer peripheral surface of the pipe member, and are formed on the outer peripheral surface of the pipe member.

16. The external-perfusion hollow-fiber membrane module according to claim 13 , wherein the liquid introduction portion includes a plurality of liquid passage ports arranged in a circumferential direction of the pipe member when viewed in the axial direction of the pipe member.

17. The external-perfusion hollow-fiber membrane module according to claim 1 , wherein the hollow-fiber membrane is folded back in a U-shape in the hollow-fiber membrane bundle, and both ends thereof are buried in the potting portion, whereby the one end of the hollow-fiber membrane bundle is fixed to the inside of the casing by the potting portion.

18. The external-perfusion hollow-fiber membrane module according to claim 1 , wherein the other end of the hollow-fiber membrane bundle has substantially the same height position in an extending direction of the hollow-fiber membrane bundle in which the hollow-fiber membrane bundle extends to the inside of the casing from the potting portion.

19. The external-perfusion hollow-fiber membrane module according to claim 1 , wherein the hollow-fiber membrane bundle has at least one place, which is provided with a warp fiber extending in a direction perpendicular to an extending direction to connect the plurality of the hollow-fiber membranes to each other, in the extending direction of the hollow-fiber membrane bundle in which the hollow-fiber membrane bundle extends to the inside of the casing from the potting portion.

20. The external-perfusion hollow-fiber membrane module according to claim 1 , wherein the casing has a cylindrical shape.

21. An inkjet printer comprising the hollow-fiber membrane module according to claim 20 .