Abstract: A composite semipermeable membrane includes a porous supporting membrane and a separation functional layer, in which, in cross-sections having a length of 2.0 ?m in a membrane surface direction, the average number density of projections in the separation functional layer which have a height of one-fifth or more of the 10-point average surface roughness is 10.0-30.0 projections/?m and the projections have an average height less than 100 nm, and in which a water production rate and a salt rejection are predetermined values or more after an aqueous solution is passed through under certain conditions.

Abstract: The present invention relates to a composite semipermeable membrane comprising a substrate, a support layer, and a separation function layer, wherein: the support layer includes particles and a thermoplastic resin having a porous structure; the particles are present in the thermoplastic resin and contain at least one material selected from the group consisting of a diene polymer, an acrylic polymer, and an ethylenic polymer; and in a cross section of the support layer, taken in the laser thickness direction, 6 or more of the particles are present in an area which is 3 ?m from the surface of the support layer in the layer thickness direction and 3 ?m in the direction along which such surface extends.

Abstract: Provided is a composite semipermeable membrane, comprising: a microporous support membrane which comprises a substrate and a porous support, and a polyamide separation functional layer formed on the microporous support membrane, wherein the polyamide has an irreversible heat absorption, which is measured using temperature modulated DSC, of 275 J/g or more at a temperature in the range of ?20 to 150° C. in the first heating process. Provided is a high-performance composite semipermeable membrane having high chemical durability, high water permeation and high rejection.

Abstract: To provide a composite semipermeable membrane capable of maintaining high removal performance even after its supporting membrane has come into contact with an aqueous solution high in salt concentration. A composite semipermeable membrane including: a supporting membrane which includes a substrate and a porous supporting layer; and a separation functional layer provided on the porous supporting layer, in which a strength to peel the porous supporting layer away from the substrate is 1.1 N/25 mm or higher.

Abstract: An object of the present invention is to provide a composite semipermeable membrane which has practical water permeability and removing properties and has a high boron removal ratio even after contact with chlorine. A composite semipermeable membrane of the present invention is a composite semipermeable membrane including a substrate, a porous supporting layer and a separation functional layer, which are superposed in this order, in which the separation functional layer includes a crosslinked fully aromatic polyamide, and the crosslinked fully aromatic polyamide has a molar ratio (amide group content) between a total molar proportion of a polyfunctional amine and a polyfunctional aromatic acid halide and a molar proportion of an amide group of 0.86-1.20.

Abstract: An object of the present invention is to provide a composite semipermeable membrane which has practical water permeability and high alkali resistance. The composite semipermeable membrane of the present invention includes: a supporting membrane including a substrate and a porous supporting layer; and a separation functional layer disposed on the porous supporting layer of the supporting membrane, in which the separation functional layer includes a crosslinked fully aromatic polyamide, and when a carboxyl group/amide group molar ratio of the separation functional layer measured by a 13C solid NMR spectroscopy is expressed by x, x is 0.54 or less.

Abstract: Provided is a semipermeable membrane having at least a separating functional layer, wherein azo compounds are retained in the separating functional layer, and the separating functional layer has a yellow index of 10 to 40. Also provided is a method of producing the semipermeable membrane. The present invention provides a semipermeable membrane having not only high water permeability but also high rejection performance even for substances that are nondissociative in the neutral range, such as boric acid, and showing high durability and a manufacturing method therefor.

Abstract: An object of the invention is to provide a composite semipermeable membrane which has the high ability to remove substances other than water and high water permeability and which suffers little decrease in performance due to fouling. The invention relates to a composite semipermeable membrane including: a supporting membrane having a substrate and a porous supporting layer disposed on the substrate; and a separation functional layer disposed on the supporting membrane, in which, in any ten sites of cross-sections of the composite semipermeable membrane which have a width of 2.0 ?m in a membrane surface direction, the projections having a height of one-fifth or more of a 10-point average surface roughness of the separation functional layer have a standard deviation of height of 60 nm or less.

Abstract: A composite semipermeable membrane includes a porous supporting membrane and a separation functional layer, in which, in cross-sections having a length of 2.0 ?m in a membrane surface direction, the average number density of projections in the separation functional layer which have a height of one-fifth or more of the 10-point average surface roughness is 10.0-30.0 projections/?m and the projections have an average height less than 100 nm, and in which a water production rate and a salt rejection are predetermined values or more after an aqueous solution is passed through under certain conditions.

Abstract: To provide a composite semipermeable membrane capable of maintaining high removal performance even after its supporting membrane has come into contact with an aqueous solution high in salt concentration. A composite semipermeable membrane including: a supporting membrane which includes a substrate and a porous supporting layer; and a separation functional layer provided on the porous supporting layer, in which a strength to peel the porous supporting layer away from the substrate is 1.1 N/25 mm or higher.

Abstract: A composite semipermeable membrane includes: a supporting membrane having a substrate and a porous supporting layer; and a separation functional layer provided on the supporting membrane, in which, when any 10 cross sections of the composite semipermeable membrane, having a length of 2.0 ?m in a membrane surface direction, are observed using an electron microscope, an average number density of projections on the separation functional layer, which have a height equivalent to or higher than ? of a 10-point average surface roughness of the separation functional layer, is 10.0 pieces/?m or more, in each cross section, and an average height of the projections is 100 nm or more.

Abstract: A composite semipermeable membrane includes a porous support membrane made of a substrate and a porous support layer and a polyamide separation-functional layer disposed on the porous support layer, wherein the zeta potential of the separation-functional layer at pH 6 is ?20 mV or lower, and the zeta potential difference between potentials of the separation-functional layer at pH 10 and pH 3 is 25 mV or smaller, and has high water permeability and high salt rejection performance and high acid/alkali durability.

Abstract: Provided is a composite semipermeable membrane, comprising: a microporous support membrane which comprises a substrate and a porous support, and a polyamide separation functional layer formed on the microporous support membrane, wherein the polyamide has an irreversible heat absorption, which is measured using temperature modulated DSC, of 275 J/g or more at a temperature in the range of ?20 to 150° C. in the first heating process. Provided is a high-performance composite semipermeable membrane having high chemical durability, high water permeation and high rejection.

Abstract: Provided is a composite semipermeable membrane having a polyamide separation-functional layer on a porous support layer, wherein the polyamide separation-functional layer has a yellow index of 10 to 40, and the actual length of the polyamide separation-functional layer per 1 ?m-length of the porous support layer is from 2 ?m to 5 ?m, or a composite semipermeable membrane having on a porous support layer a polyamide separation-functional layer prepared by polycondensation of polyfunctional amines with polyfunctional acid halides, wherein the polyamide separation-functional layer is formed by the steps of (A) interfacial polycondensation in which polyfunctional amines and polyfunctional acid halides are brought into contact at 40° C. to 70° C. and subsequent (B) heat treatment at 70° C. to 150° C. The composite semipermeable membrane according to the present invention has high boron removal performance and high water permeation performance.

Abstract: Provided is a semipermeable membrane having at least a separating functional layer, wherein azo compounds are retained in the separating functional layer, and the separating functional layer has a yellow index of 10 to 40. Also provided is a method of producing the semipermeable membrane. The present invention provides a semipermeable membrane having not only high water permeability but also high rejection performance even for substances that are nondissociative in the neutral range, such as boric acid, and showing high durability and a manufacturing method therefor.