A method for removing ethylene from the atmosphere surrounding an agricultural product that is sensitive to ethylene, which promotes climacteric ripening and senescence, is disclosed. The method uses a membrane for selective ethylene permeation and removal from a container that is used to store, transport, and preserve the agricultural product.

[Problem] Provided is a semipermeable membrane that achieves chemical resistance (chlorine resistance, acid resistance, alkali resistance), membrane performance, and membrane strength by sulfonating a polyphenylene-based semipermeable membrane base material under specific conditions. [Solution] A polyphenylene-based semipermeable membrane that is composed of a material containing a polyphenylene-based resin, wherein the semipermeable membrane has a first surface of which at least a portion is sulfonated, and wherein, when concentration distribution of elemental sulfur derived from a sulfonic acid group is measured by elemental analysis in a cross section in a thickness direction of the semipermeable membrane, a ratio of a sulfonated layer obtained by the following expression is 50% or less: Ratio of Sulfonated Layer (%)=Sulfonated Layer Thickness/(Sulfonated Layer Thickness+Non-Sulfonated Layer Thickness)×100.

[Problem] Provided is a semipermeable membrane that achieves chemical resistance (chlorine resistance, acid resistance, alkali resistance), membrane performance, and membrane strength by sulfonating a polyphenylene-based semipermeable membrane base material under specific conditions. [Solution] A polyphenylene-based semipermeable membrane that is composed of a material containing a polyphenylene-based resin, wherein the semipermeable membrane has a first surface of which at least a portion is sulfonated, and wherein, when concentration distribution of elemental sulfur derived from a sulfonic acid group is measured by elemental analysis in a cross section in a thickness direction of the semipermeable membrane, a ratio of a sulfonated layer obtained by the following expression is 50% or less: Ratio of Sulfonated Layer (%)=Sulfonated Layer Thickness/(Sulfonated Layer Thickness+Non-Sulfonated Layer Thickness)×100.

An object of the present invention is to provide a method for producing a treatment liquid, having excellent filterability.

The method for producing a treatment liquid of an embodiment of the present invention is a method for producing a treatment liquid, the method including filtering an object to be purified including a surfactant, using a first filter having a first filter medium, to produce a treatment liquid for a semiconductor substrate, in which the first filter medium includes at least one selected from the group consisting of a nylon, a polyallyl sulfonic acid, a perfluoroalkoxy alkane which has been subjected to a hydrophilization treatment, a polytetrafluoroethylene which has been subjected to a hydrophilization treatment, a polyolefin which has been subjected to a hydrophilization treatment, and a polyvinylidene fluoride which has been subjected to a hydrophilization treatment, and the surfactant includes at least one selected from the group consisting of a nonionic surfactant including a group represented by Formula (1) and an anionic surfactant including a group represented by Formula (1).

Formula (1) (LO).sub.n

L represents an alkylene group, and n represents 3 to 55.

An object of the present invention is to provide a method for producing a treatment liquid, having excellent filterability.

The method for producing a treatment liquid of an embodiment of the present invention is a method for producing a treatment liquid, the method including filtering an object to be purified including a surfactant, using a first filter having a first filter medium, to produce a treatment liquid for a semiconductor substrate, in which the first filter medium includes at least one selected from the group consisting of a nylon, a polyallyl sulfonic acid, a perfluoroalkoxy alkane which has been subjected to a hydrophilization treatment, a polytetrafluoroethylene which has been subjected to a hydrophilization treatment, a polyolefin which has been subjected to a hydrophilization treatment, and a polyvinylidene fluoride which has been subjected to a hydrophilization treatment, and the surfactant includes at least one selected from the group consisting of a nonionic surfactant including a group represented by Formula (1) and an anionic surfactant including a group represented by Formula (1).

Formula (1) (LO).sub.n

L represents an alkylene group, and n represents 3 to 55.

A composite semipermeable membrane 12 of the present invention includes a porous support membrane 12a and a skin layer 12b supported by the porous support membrane 12a. The membrane surface of the composite semipermeable membrane 12 has an elastic modulus of 250 MPa or more and 500 MPa or less as calculated by force curve measurement using AFM in water. A spiral membrane element 20 of the present invention includes the composite semipermeable membrane 12 of the present invention. A water treatment system 100 of the present invention includes the spiral membrane element 20 of the present invention.

A composite semipermeable membrane 12 of the present invention includes a porous support membrane 12a and a skin layer 12b supported by the porous support membrane 12a. The membrane surface of the composite semipermeable membrane 12 has an elastic modulus of 250 MPa or more and 500 MPa or less as calculated by force curve measurement using AFM in water. A spiral membrane element 20 of the present invention includes the composite semipermeable membrane 12 of the present invention. A water treatment system 100 of the present invention includes the spiral membrane element 20 of the present invention.

A functional polymer membrane having a pore volume fraction of 0.6% or more and 3.0% or less by allowing a reaction of curing a composition containing a polymerizable compound (A) and a copolymerizable monomer (B).

A functional polymer membrane having a pore volume fraction of 0.6% or more and 3.0% or less by allowing a reaction of curing a composition containing a polymerizable compound (A) and a copolymerizable monomer (B).

An electrode, process for preparing the electrode and devices thereof. An electrode comprising at least one metal deposited on a substrate; and at least one electrically conducting polymer. The devices comprising the electrode for energy storage and molecular separation.