A filter medium includes a first porous PTFE membrane, a first air-permeable support member, a second porous PTFE membrane, and a second air-permeable support member. A surface of the filter medium is formed by the first porous PTFE membrane. A bond strength, as measured by a 180 peel test, between the first porous PTFE membrane and the first air-permeable support member is higher than 1.2 N/25 mm. The first air-permeable support member is an embossed non-woven fabric having one or more recessed portions and one or more projecting portions. A ratio of the area of the recessed portion or the total area of the recessed portions to the area of the embossed non-woven fabric serving as the first air-permeable support member is more than 15%.

The purpose of the present invention is to provide a composite semipermeable membrane having achieved both strength and water-permeable properties. This composite semipermeable membrane is provided with a substrate, a porous support body disposed on the substrate, and a separation function layer provided on the porous support body. The substrate has a structure provided with a crimped portion and a non-crimped portion. The porous support body is impregnated inside a crimped portion and inside a non-crimped portion of the substrate.

The present invention relates to a polyelectrolyte multilayer (PEM) membrane comprised of at least one bilayer, wherein the bilayer is comprised of a layer of a polymeric polycation and a layer of a polymeric polyanion. Furthermore, present invention relates to methods for the production of these PEM membranes by layer-by-layer deposition and the use of these PEM membranes for the decontamination of liquids, preferably water.

A filtration membrane coating comprising a hydrophilic polymer, a surfactant, and one or more charged compounds, each containing one or more sulfonate functionalities and one or more linkable functionalities selected from the group consisting of amine, monochlorotriazine, and dichlorotriazine. The hydrophilic polymer and surfactant form a thin primer layer which is also superhydrophilic. The primer layer improves flux, and enables improved adhesion of the one or more charged compounds, which form a charged dye layer on top of the primer layer when enhances rejection of charged divalent ions. The coating can be applied while the membrane is packaged in its final form, such as in a spiral wound or other configuration.

This invention is directed to an aromatic material based free-standing film, a hybrid of organic crystalline materials and inorganic carbon nanomaterials, process of preparation and uses thereof. The film, which comprises a fibrous organic nanocrystals of an aromatic material, is mechanically and thermally stable. This film is optionally reinforced by hybridization with a reinforcement material, such as carbon nanotube, carbon material, a polysaccharide, a nanoclay a metal, metal alloy, or an organic polymer. The hybrid film of organic nanocrystals and carbon nanotubes (ONC/CNT) has high conductivity and high thermal stability. The films or hybrids of this invention are used as microfiltration membranes for various materials, in electrodes or perovskite solar cells.

A method for filtering a protein-containing liquid containing protein at a concentration of 20 mg/mL or more and 100 mg/mL or less, the method including a prefiltration step of filtering the protein-containing liquid by a prefilter having a pore size of 0.08 m to 0.25 m and including a hydrophobic resin, and a virus removal step of filtering the protein-containing liquid by a virus removal membrane including a synthetic polymer, after the prefiltration step, wherein the protein-containing liquid before conducting the prefiltration step includes 0.25 g or more of a trimer or higher multimer of the proteins having an average diameter of less than 100 nm, per 1 m.sup.2 of the virus removal membrane.

This ionic liquid-containing laminate includes a porous layer having affinity with ionic liquids (C), said layer holding an ionic liquid-containing liquid (A) within voids therein, and a porous layer lacking affinity with ionic liquids (B). The porous layer having affinity with ionic liquids (C) may include an inorganic material (e.g., metal oxide particles having an average particle size of 0.001 to 10 m on a number basis). The ionic liquid-containing liquid (A) may include an ionic liquid containing cations selected from ammonium, imidazolium and phosphonium cations, and anions selected from fluorine-containing anions, cyano-containing anions and amino acid-derived anions. The porous layer having affinity with ionic liquids (C) may include 1 to 100 volume parts of the ionic liquid-containing liquid (A) with respect to 100 volume parts of voids therein. The ionic liquid-containing laminate is easily formable, and is able to stably hold (or fix) the ionic liquid while maintaining said liquid in a liquid state.

A device for isolating DNA from a sample containing cells, including a cartridge having an entrance port and an exit port, a membrane disposed between the entrance port and the exit port, and a plurality of channels between the membrane and the exit port. Additionally, systems and methods for isolating DNA from a sample containing cells and also systems and methods for amplifying and isolating single-stranded DNA from a sample containing DNA.

Nanostructured polyelectrolyte bilayers deposited by Layer-by-Layer deposition on nanoporous membranes can be selectively crosslinked to modify the polyelectrolyte charge density and control ionic selectivity independent of ionic conductivity. For example, the polyelectrolyte bilayer can comprise a cationic polymer layer, such as poly(ethyleneimine), and an anionic polymer layer, such as poly(acrylic acid). Increasing the number of bilayers increases the cation selectivity when the poly(ethyleneimine) layer is crosslinked with glutaraldehyde. Crosslinking the membranes also increases the chemical and mechanical strength of the polyelectrolyte films. This controllable and inexpensive method can be used to create ion-selective and mechanically robust membranes on porous supports for a wide range of applications.

The present invention addresses the problem of providing: a composite hollow-fiber membrane having high permeability and high membrane strength; and a production method therefor. The present invention pertains to a composite hollow-fiber membrane that at least has a layer (A) and a layer (B), wherein the layer (A) contains a thermoplastic resin, the layer (A) is provided with a co-continuous structure comprising voids and a phase containing the thermoplastic resin, the co-continuous structure has a structural cycle of 1-1000 nm, and the hole area rate H.sub.A of the layer (A) and the hole area rate H.sub.B of the layer (B) fulfill the relation: H.sub.A<H.sub.B.