Provided is a porous membrane including polytetrafluoroethylene and/or modified polytetrafluoroethylene having a small pore diameter, thin film thickness, high porosity, and high strength; and a method for manufacturing the same. The porous membrane including polytetrafluoroethylene and/or modified polytetrafluoroethylenehas bubble point of isopropyl alcohol according to JIS K3832 of 600 kPa or more, and tensile strength according to JIS K6251 of 90 MPa or more.

A composite that includes an expanded polytetrafluoroethylene (ePTFE) membrane having a porous microstructure. The porous microstructure of the ePTFE membrane is impregnated with a stiffening polymer. An acoustic device assembly that includes the composite and an acoustic device is also described. The composite and the acoustic device assembly can exhibit an insertion loss of less than 7 dB at 1 kHz when measured by the Acoustic Response Measurement (“ARM”) Test.

The invention relates to a mechanically stable ultrafiltration membrane and to a method for producing such an ultrafiltration membrane.

Described are porous, sintered metal bodies that include multiple layers made from different metal particles and that may be useful as porous filter membranes, as well as methods of making and using the porous, sintered metal bodies.

A polymer electrolyte membrane according to the present invention has a cluster diameter of 2.96 to 4.00 nm and a converted puncture strength of 300 gf/50 μm or more. The polymer electrolyte membrane according to the present invention has a low electric resistance and an excellent mechanical strength.

A polyolefin microporous film having a laminated structure provided with at least one layer A containing a polyolefin and at least one layer B containing a polyolefin. 0 mass % to less than 3 mass % of polypropylene is contained in layer A and 1 mass % to less than 30 mass % of polypropylene is contained in layer B. When the proportion of polypropylene contained in layer A is represented by PPA (mass %) and the proportion of polypropylene contained in layer B is represented by PPB (mass %), PPB>PPA. In the polyolefin microporous film, the heat shrinkage ratio in TD at 120° C. measured upon applying, in MD, a constant load determined on the basis of the relationship: load (gf)=0.01×piercing strength (gf) of polyolefin microporous film×length (mm) in TD of polyolefin microporous film, is 10 to 40% inclusive.

The present invention relates to a separation membrane including a thermoplastic polymer selected from a cellulose ester and a polyamide, in which, when regions obtained by dividing a cross-sectional surface perpendicular to a longitudinal direction of the separation membrane into 5 at an equal interval are defined as regions 1 to 5, all the regions 1 to 5 have a number average pore diameter changing rate a of −0.25 to 0.25, and at least one of the regions 1 to 5 is a region P that satisfies conditions (a) and (b): (a) a value of area average pore diameter D.sub.s/number average pore diameter D.sub.n is 2.50 to 6.00; and (b) a number average W of fine pores that are located at a distance smaller than L.sub.a from a center of respective coarse pores is 10 to 30.

The present invention relates to a lipophilic and hydrophobic nanofiber membrane and a method of preparing the same. The lipophilic and hydrophobic nanofiber membrane according to an exemplary embodiment may be compressed at a pressure of 10 kPa to 100 kPa and may have an average thickness of 10 μm to 1,500 μm.

The problem of the present invention is to provide a novel polytetrafluoroethylene porous film having a small pore diameter, small film thickness, high porosity, and high strength, and a production method thereof.

The present invention provides a polytetrafluoroethylene porous film, wherein a bubble point in isopropyl alcohol (IPA) according to JIS K3832 is not less than 400 kPa, and a tensile strength based on JIS K6251 is not less than 50 MPa.

Provided is a method for manufacturing a long-life brewed alcoholic beverage by a filtration process with the use of a porous membrane involving a washing step, whereby a high tolerance (chemical tolerance) to a washing solution (a chemical solution) and a good filtration performance are achieved. A method for ma manufacturing a second brewed alcoholic beverage which includes: a filtration step for passing a first brewed alcoholic beverage, which contains a yeast and a high-molecular substance or sediment component produced through fermentation by the yeast, through a porous membrane, which is formed of a resin having a three-dimensional network structure, to thereby separate the second brewed alcoholic beverage from the yeast; and a washing step for passing a washing solution through the porous membrane or immersing the porous membrane in the washing solution to thereby wash the inside of the porous membrane.