Abstract: An object of the present invention is to provide a separation membrane having high permeability and selective removability of divalent/monovalent ions. The separation membrane of the present invention includes a supporting membrane and a separation functional layer formed on the supporting membrane, in which the separation functional layer contains a polymerized product of a polyfunctional amine with a polyfunctional acid halide, the polyfunctional amine contains a polyfunctional aliphatic amine as a main component, the separation functional layer has a hollow protuberant structure, and the separation functional layer has a relative surface area of 1.1-10.0.

Abstract: Provided is a filter having either or both of a winding and a laminate that include a fiber-like absorbing material, wherein the fiber-like absorbing material has a base material and metal particles supported on the base material, and the diameter D of the fiber-like absorbing material, the void fraction of the winding or laminate, and the variation in the area void fraction in the radial direction of the winding or the variation in the area void fraction in the direction of lamination are in a specific range.

Abstract: The present invention provides a filter which, even when raw water is subjected to high-speed treatment, enables achieving a high solute rejection ratio and a long solute filtration life and which exhibits a low water flow resistance. The present invention pertains to a filter obtained by laminating woven fabrics or knitted fabrics, the filter being characterized in that: said woven fabrics or knitted fabrics comprise a fiber capable of adsorbing components dissolved in liquid: said fiber has a diameter of 100-600 ?m; the woven fabrics or knitted fabrics have a porosity of 15-70%; and variation in area porosity in the thickness direction of the laminate is 15% or less.

Abstract: The present invention provides a filter which, even when raw water is subjected to high-speed treatment, enables achieving a high solute rejection ratio and a long solute filtration life and which exhibits a low water flow resistance. The present invention pertains to a filter obtained by laminating woven fabrics or knitted fabrics, the filter being characterized in that: said woven fabrics or knitted fabrics comprise a fiber capable of adsorbing components dissolved in liquid: said fiber has a diameter of 100-600 ?m; the woven fabrics or knitted fabrics have a porosity of 15-70%; and variation in area porosity in the thickness direction of the laminate is 15% or less.

Abstract: The present invention relates to an ion exchange fiber including: a core fiber; and an ion exchange layer that is disposed at a vicinity of the core fiber and includes a crosslinked polymer compound having an ion exchange group, in which, in a cross section perpendicular to a longitudinal direction of the ion exchange fiber, an area of the ion exchange layer occupies 50% or more and 90% or less of a total cross sectional area, and the ion exchange fiber has a swelling ratio of 50% or less.

Abstract: An object of the present invention is to provide a separation membrane having high permeability and selective removability of divalent/monovalent ions. The separation membrane of the present invention includes a supporting membrane and a separation functional layer formed on the supporting membrane, in which the separation functional layer contains a polymerized product of a polyfunctional amine with a polyfunctional acid halide, the polyfunctional amine contains a polyfunctional aliphatic amine as a main component, the separation functional layer has a hollow protuberant structure, and the separation functional layer has a relative surface area of 1.1-10.0.

Abstract: The present invention provides a separation membrane that is usable at a high temperature and a high pressure. The solvent-resistant separation membrane of the present invention has an average pore diameter of the separation membrane surface of 0.005 to 1 ?m and includes a portion where a degree of cyclization (I1600/I2240) as measured by the total reflection infrared absorption spectroscopy is 0.5 to 50.