| abstract |
(57) [Summary] [Purpose] Suitable as a filter material for solid-liquid separation, with high porosity, and capable of controlling the membrane structure on the inner surface of the tube in a wide range according to the purpose and application. To provide a tubular porous PTFE composite membrane having excellent filtration performance. [Structure] The porous tetrafluoroethylene resin tube (a) has a porous tetrafluoroethylene resin sheet (b1) or a porous tetrafluoroethylene resin sheet and a synthetic resin having a melting point lower than that of the tetrafluoroethylene resin. A tubular porous multilayer membrane, wherein at least one layer of a fluid-permeable laminated sheet (b2) laminated with a sheet is integrally fixed by heat fusion, and a method for producing the same. A tubular porous multilayer membrane module using the tubular porous multilayer membrane. |