In accordance with at least selected embodiments, a battery separator or separator membrane comprises one or more co-extruded multi-microlayer membranes optionally laminated or adhered to another polymer membrane. The separators described herein may provide improved strength, for example, improved puncture strength, particularly at a certain thickness, and may exhibit improved shutdown and/or a reduced propensity to split.

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.

In accordance with at least selected embodiments, a battery separator or separator membrane comprises one or more co-extruded multi-microlayer membranes optionally laminated or adhered to another polymer membrane. The separators described herein may provide improved strength, for example, improved puncture strength, particularly at a certain thickness, and may exhibit improved shutdown and/or a reduced propensity to split.

A separator for alkaline water electrolysis (1) comprising a porous hydrophilic polymer layer (20), the porous hydrophilic polymer layer comprising a polymer resin and hydrophilic inorganic particles, characterized in that the inorganic particles are barium-sulfate particles having a particle size D50 of 0.7 pm or less.

This application is directed to new and/or improved MD and/or TD stretched and optionally calendered membranes, separators, base films, microporous membranes, battery separators including said separator, base film or membrane, batteries including said separator, and/or methods for making and/or using such membranes, separators, base films, microporous membranes, battery separators and/or batteries. For example, new and/or improved methods for making microporous membranes, and battery separators including the same, that have a better balance of desirable properties than prior microporous membranes and battery separators. The methods disclosed herein comprise the following steps: 1.) obtaining a non-porous membrane precursor; 2.) forming a porous biaxially-stretched membrane precursor from the non-porous membrane precursor; 3.) performing at least one of (a) calendering, (b) an additional machine direction (MD) stretching, (c) an additional transverse direction (TD) stretching, and (d) a pore-filling on the porous biaxially stretched precursor to form the final microporous membrane. The microporous membranes or battery separators described herein may have the following desirable balance of properties, prior to application of any coating: a TD tensile strength greater than 200 or 250 kg/cm2, a puncture strength greater than 200, 250, 300, or 400 gf, and a JIS Gurley greater than 20 or 50 s.

In accordance with at least selected embodiments, a battery separator or separator membrane comprises one or more co-extruded multi-microlayer membranes optionally laminated or adhered to another polymer membrane. The separators described herein may provide improved strength, for example, improved puncture strength, particularly at a certain thickness, and may exhibit improved shutdown and/or a reduced propensity to split.

This application relates to a separator for a rechargeable battery. The separator includes a porous substrate and a coating layer on at least one surface of the porous substrate. The coating layer includes a binder including a fluorine-based binder and a (meth)acryl-based binder, and a filler. The fluorine-based binder includes a first structural unit derived from vinylidene fluoride and a second structural unit derived from at least one monomer of hexafluoropropylene, chlorotrifluoroethylene, trifluoroethylene, ethylene tetrafluoride, and ethylene monomers, and the second structural unit is included in an amount of 10 wt % or less with respect to the fluorine-based binder. The fluorine-based binder includes a first fluorine-based binder having a weight average molecular weight of 800,000 to 1,500,000 and a second fluorine-based binder having a weight average molecular weight of less than or equal to 600,000. The (meth)acryl-based binder has pencil hardness of 5H or higher.

In accordance with at least selected embodiments, a battery separator or separator membrane comprises one or more co-extruded multi-microlayer membranes optionally laminated or adhered to another polymer membrane. The separators described herein may provide improved strength, for example, improved puncture strength, particularly at a certain thickness, and may exhibit improved shutdown and/or a reduced propensity to split.

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.

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.