Toray Industries, Inc.

Koichi Takada

Gohei Yamamura

Hiroki Tomioka

Ryuichiro Hiranabe

Hiroki Eimura

Masayuki Hanakawa

Kenta Iwai

Takahiro Tokuyama

Marina Otsuka

The present invention relates to a separation membrane including a thermoplastic polymer selected from a cellulose ester and a polyamide, in which, when regions obtained by dividing a cross-sectional surface perpendicular to a longitudinal direction of the separation membrane into 5 at an equal interval are defined as regions 1 to 5, all the regions 1 to 5 have a number average pore diameter changing rate &#x3b1;of &#x2212;0.25 to 0.25, and at least one of the regions 1 to 5 is a region P that satisfies conditions (a) and (b): (a) a value of area average pore diameter D/number average pore diameter Dis 2.50 to 6.00; and (b) a number average W of fine pores that are located at a distance smaller than Lfrom a center of respective coarse pores is 10 to 30.

Separation membrane and method for producing separation membrane

The present invention addresses the problem of providing a separating membrane mainly comprising a thermoplastic resin having high permeability. The present invention relates to a separating membrane including a thermoplastic resin, wherein the width of voids in the separating membrane is at least equal to 1 nm and at most equal to 1000 nm, and the curvature rate of the voids is at least equal to 1.0 and at most equal to 6.0.

Separating membrane and method for manufacturing separating membrane

The present invention addresses the problem of providing: a composite hollow-fiber membrane having high permeability and high membrane strength; and a production method therefor. The present invention pertains to a composite hollow-fiber membrane that at least has a layer (A) and a layer (B), wherein the layer (A) contains a thermoplastic resin, the layer (A) is provided with a co-continuous structure comprising voids and a phase containing the thermoplastic resin, the co-continuous structure has a structural cycle of 1-1000 nm, and the hole area rate Hof the layer (A) and the hole area rate Hof the layer (B) fulfill the relation: H&#x3c;H.

Composite hollow-fiber membrane and production method therefor

The purpose of the present invention is to provide: a separation film that consists primarily of a cellulose ester and has a high membrane strength and a high elongation degree; and a production method therefor. Provided is a separation film which has a structure comprising a cellulose ester phase and pores, wherein the average pore diameter R is 0.001-6 &#x3bc;m, the value obtained from the expression: breaking strength (MPa)&#xf7;(100&#x2212;porosity (%))&#xd7;100 is 40 or greater, and the elongation degree is 10% or greater.

Separation film and production method therefor

A problem to be solved by the present invention is to provide a separation membrane having excellent separation performance, having high membrane strength and high permeation performance, and mainly including a cellulose-based resin. The present invention is concerned with a separation membrane including a cellulose ester, having, in the interior thereof, voids each having a specified structure, and having a tensile elasticity of 1,000 to 6,500 MPa.

Separation membrane

The present invention provides a separation membrane having excellent separation performance and permeation performance, having high membrane strength, and mainly including a cellulose-based resin. The present invention relates to a separation membrane containing a cellulose ester and having a tensile elasticity of 1,500 to 6,500 MPa.

The problem addressed by the present invention is to provide a separation membrane with superior permeation performance and separation performance and having few occurrences of defects. The present invention relates to a separation membrane wherein: the separation membrane has a layer (I) with a thickness of 0.5-100 &#x3bc;m; letting, in a cross-section in the direction of thickness of the layer (I), region a be a region with a depth of 50-150 nm from a surface (surface A), region b a region with a depth of 50-150 nm from the other surface (surface B), and region c a region with a thickness of 100 nm where the depth from both surfaces is the same, the average pore diameter Pa for region a and the average pore diameter Pb for region b are both 0.3-3.0 nm and the average pore diameter Pc for region c is 3.0 nm or less; and the percentage of open area Ha for region a, the percentage of open area Hb for region b, and the percentage of open area Hc for region c satisfy the following equations. 2Hc&#x3c;Ha 2Hc&#x3c;Hb

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 &#x3bc;m and an inner diameter of 14 to 250 &#x3bc;m, 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 &#x3bc;m, and the open pore ratio Hof the layer (A) and the open pore ratio Hof the layer (B) satisfy H&#x3c;H.

Composite hollow fiber membrane and method for producing same

An object of the present invention is to provide a multilayer separation membrane having excellent performance on both removal of suspended solids in water and adsorptive removal of metal ions in water. A multilayer separation membrane of the present invention includes: a porous adsorption layer including substantially a polymer having chelating functional groups; and a porous clarification layer, and the porous clarification layer is disposed neater to a raw water-side than the porous adsorption layer.

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Shiga, Japan

Koichi Takada