Kuraray Co., Ltd.

Hirokuni Tanii

Syuji Kawai

Taku Tanaka

Shuzo Yamashita

Akira Kubotsu

Tosirou Yamaguchi

Hisaharu Kuwahara

Koichi Takakura

Kazuhisa Yamauchi

Yoshio Ohfuji

Satoshi Bando

A novel porous fibrous structure containing from 10 to 100% by weight of wet heat bonding fibers, having cellular cavities in the fibrous structure of the fibers, in which a plurality of indefinite cellular cavities are present independently or in a state of partially connected in the inside of the fibrous structure, at least a portion of the fibers constituting the fibrous structure is heat bonding by the wet heat bonding fibers, and a process for producing such porous fibrous structure.

Porous fibrous structure and process for producing the same

Liquid curable resins, such as unsaturated polyester resins, unsaturated epoxy resins, polymethyl methacrylates, are cured in a mold, the casting surface of which, is made of a vinyl alcohol-olefin copolymer to produce a shaped resinous article with an improved and even surface gloss.

Method of producing shaped resinous articles

There is provided a hollow fiber membrane of ethylene-vinyl alcohol copolymer which is produced by a process comprising extruding a spinning solution of an ethylene-vinyl alcohol copolymer in a solvent selected from the group consisting of dimethylsulfoxide, dimethylacetamide, pyrrolidone, N-methylpyrrolidone and mixtures thereof through a hollow fiber spinneret while a liquid coagulant is introduced into a central aperture of said spinneret, passing the spun fiber through a gaseous atmosphere in a manner such that the fiber is drawn 0.5 to 20 times its extrusion rate and then coagulating said fiber in a coagulating bath at a temperature within the range satisfying the following relationship:

Ethylene-vinyl alcohol hollow fiber membrane and method for the

A hollow fiber membrane made of an ethylene-vinyl alcohol copolymer is provided, which is characterized in that, when observed in a dry state with an electron microscope, the hollow fiber membrane has at least one dense, active layer (or skin layer) on the inside and/or outside surface thereof and further a three-layered structure comprising two layers respectively contacting the inside and outside surfaces and each consisting of a plurality of particles bonded together and having particle sizes of 0.01 to 2 microns and a substantially particle-free homogeneous layer lying between the two layers. A method of producing such hollow fiber membranes is also provided comprising spinning a spinning solution prepared by dissolving an ethylene-vinyl alcohol copolymer in a solvent mainly consisting of dimethyl sulfoxide, dimethylacetamide, pyrrolidone, N-methylpyrrolidone or a mixture of these through a spinneret for hollow fiber production while simultaneously introducing a coagulating liquid through the central aperture of said spinneret, passing the spun fiber through a gaseous atmosphere such that the fiber is drawn to 3 to 30 times its original length, and coagulating the fiber in a coagulation bath at a temperature within the range specified below:

Method of producing ethylene-vinyl alcohol copolymer hollow fiber

A hollow fiber membrane made of an ethylene-vinyl alcohol copolymer is provided, which is characterized in that, when observed in a dry state with an electron microscope, the hollow fiber membrane has at least one dense, active layer (or skin layer) on the inside and/or outside surface thereof and further a three-layered structure comprising two layers respectively contacting the inside and outside surfaces and each consisting of a plurality of particles bonded together and having particle sizes of 0.01 to 2 microns and a substantially particle-free homogeneous layer lying between the two layers. A method of producing such hollow fiber membranes is also provided comprising spinning a spinning solution prepared by dissolving an ethylene-vinyl alcohol copolymer in a solvent mainly consisting of dimethyl sulfoxide, dimethylacetamide, pyrrolidone, N-methylpyrrolidone or a mixture of these through a spinneret for hollow fiber production while simultaneously introducing a coagulating liquid through the central aperture of said spinneret, passing the spun fiber through a gaseous atmosphere such that the fiber is drawn to 3 to 30 times its extrusion rate, and coagulating the fiber in a coagulation bath at a temperature within the range specified below:

Ethylene-vinyl alcohol copolymer hollow fiber membranes and method of

There is described an ethylene-vinyl alcohol copolymer membrane comprising at least a skin layer on its surface and a porous layer supporting the skin layer. The porous layer, when the membrane is observed in the dry state with an electron microscope, contains vacuoles or voids, which present a mono- or multi-layer structure and have straight-line lengths corresponding to 20-99% of the whole thickness of the membrane. In addition, the polymer portion of the porous layer has micropores with an average pore diameter of 0.1-5 microns and the membrane has a porosity of 60-90%.

Ethylene-vinyl alcohol copolymer membrane and a method for producing the

The invention relates to a blood dialyzing apparatus comprising at least one bundle of semi-permeable hollow filaments and a cylindrical housing positioning said bundle of filaments and having a large length to inside diameter ratio of 7 to 10.

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Kurashiki, Japan

Hirokuni Tanii