Porous liquid-filtering membranes having a repeatable distribution of pores of a small dimension are provided, as well as pillar templates that are used to produce such liquid filtering membranes. Also disclosed are methods of making and using the pillar templates to make porous liquid filtering membranes.

A microporous membrane is made by a dry-stretch process and has substantially round shaped pores and a ratio of machine direction tensile strength to transverse direction tensile strength in the range of 0.5 to 5.0. The method of making the foregoing microporous membrane includes the steps of: extruding a polymer into a nonporous precursor, and biaxially stretching the nonporous precursor, the biaxial stretching including a machine direction stretching and a transverse direction stretching, the transverse direction stretching including a simultaneous controlled machine direction relax.

The present invention addresses the problem of providing a separating membrane mainly comprising a thermoplastic resin having high permeability. The present invention relates to a separating membrane including a thermoplastic resin, wherein the width of voids in the separating membrane is at least equal to 1 nm and at most equal to 1000 nm, and the curvature rate of the voids is at least equal to 1.0 and at most equal to 6.0.

Viral filters include a filter member featuring a first surface and a second surface and having a thickness extending between the first and second surfaces in a first direction, and a plurality of channels formed in the filter member, each of the channels having a channel axis, where during use, a solution carrying a viral load flows in a direction parallel to the first surface, and at least a portion of the viral load enters the membrane through the first surface and propagates in the first direction, and where for at least 50% of the channels in the filter member, the channel axis is oriented at an angle of between 5 degrees and 85 degrees relative to the first direction.

The present technology provides micro fabricated filtration devices, methods of making such devices, and uses for microfabricated filtration devices. The devices may allow diffusion to occur between two fluids with improved transport resistance characteristics as compared to conventional filtration devices. The devices may include a compound structure that includes a porous membrane overlying a support structure. The support structure may define a cavity and a plurality of recesses formed in a way that can allow modified convective flow of a first fluid to provide improved diffusive transport between the first fluid and a second fluid through the membrane.

The invention provides systems and methods for substantially improving the compaction resistance of isoporous block copolymer (BCP) film by adding a high molecular weight hydrophilic additive in the casting dope formulation. Systems and methods disclosed also disclose several other multifunctional enhancements to film properties including: low fouling propensity, improved permeability, improved permeability retention upon drying, and ability to tune the substructure and pore size of these novel BCP films. These porous BCP films are useful in filtration and separations applications and are amenable to standard manufacturing practices.

The invention provides systems and methods for substantially improving the compaction resistance of isoporous block copolymer (BCP) film by adding a high molecular weight hydrophilic additive in the casting dope formulation. Systems and methods disclosed also disclose several other multifunctional enhancements to film properties including: low fouling propensity, improved permeability, improved permeability retention upon drying, and ability to tune the substructure and pore size of these novel BCP films. These porous BCP films are useful in filtration and separations applications and are amenable to standard manufacturing practices.

There is provided a production method for a resist composition purified product, which includes a step (i) of filtering a resist composition with a filter having a porous structure in which adjacent spherical cells are connected to each other. The filter includes a porous membrane containing at least one resin selected from the group consisting of polyimide and polyamide imide. The resist composition contains a base material component (A) that exhibits changed solubility in a developing solution under action of acid, an onium salt, and an organic solvent component (S), where the content of the organic solvent component (S) is 97% by mass or more.

Porous liquid-filtering membranes having a repeatable distribution of pores of a small dimension are provided, as well as pillar templates that are used to produce such liquid filtering membranes. Also disclosed are methods of making and using the pillar templates to make porous liquid filtering membranes.

Track-etched membranes for filtration are provided. Filtration methods utilizing such membranes and cell culture methods are also provided.