Composite hollow fiber membrane and method for producing same

Abstract

Problems that the invention is to solve is to provide a composite hollow fiber membrane being excellent in separation performance and permeation performance, having high membrane strength, and capable of being easily produced, and a method for producing the same. The present invention relates to a composite hollow fiber membrane including at least a layer (A) and a layer (B), in which the composite hollow fiber membrane has an outer diameter of 20 to 350 μm and an inner diameter of 14 to 250 μm, the tensile modulus of the composite hollow fiber membrane is from 1,000 to 6,500 MPa, the layer (A) contains a cellulose ester, the thickness of the layer (A) is from 0.01 to 5 μm, and the open pore ratio HA of the layer (A) and the open pore ratio HB of the layer (B) satisfy HA<HB.

Dependencies are inferred from the claim text.