Cuno, Inc.

3m Innovative Properties Company

Other

Richard D Sale

Eugene A Ostreicher

Kenneth C Hou

Thomas J Hamlin

Eshan B Yeh

Richard A Prince

Michael Mezhirov

Mark W Schimmel

Norbert Roessler

John L Pulek

Peter J Leavesley

C Thomas Paul

Gokhan Kuruc

The present disclosure relates to improved efficient and effective systems and methods of manufacturing hydrophilic polyethersulfone (PES) membrane suitable for commercial applications and the resultant hydrophilic polyethersulfone (PES) membrane suitable for commercial applications produced thereby and includes methods of manufacturing hydrophilic polyethersulfone (PES) membrane comprising the acts of: providing hydrophobic PES membrane; prewetting the hydrophobic PES membrane in a sufficient amount of a liquid having a sufficiently low surface tension; exposing the wet hydrophobic PES membrane to a sufficient amount of an aqueous solution of oxidizer; and after the exposing act, heating the hydrophobic PES membrane for a sufficient time at a sufficient temperature and methods of manufacturing hydrophilic polyethersulfone (PES) membrane comprising the acts of: providing gel PES membrane; exposing the gel PES membrane to a sufficient amount of an aqueous solution of oxidizer; and after the exposing act, heating the hydrophobic PES membrane for a sufficient time at a sufficient temperature and the resulting products.

Method for preparing hydrophilic polyethersulfone membrane

A pleated filter element includes a composite depth filter medium formed into a plurality of pleats. The composite depth filter medium includes a plurality of depth filter media layers. Each of the plurality of depth filter media layers includes adsorber particulate matter. Each of the plurality of depth filter media layers may have a thickness less than about 1300 microns. The plurality of depth filter media layers may have at least 50% by weight of adsorber particulate matter.

Pleated multi-layer filter media and cartridge

Hydrophilic polyethersulfone membrane and method for preparing same

An at least two layer, unsupported, continuous microporous membrane is disclosed. The at least two layer, unsupported, continuous microporous membrane may include at least two different membrane pore size layers or the pore sizes may have about the same pore size. Apparatus and processes for fabricating at least a two layer unsupported, continuous, microporous membrane are also disclosed. One representative process disclosed for forming a continuous, unsupported, multilayer phase inversion microporous membrane having at least two layers comprises of the acts of: operatively positioning at least one dope applying apparatus, having at least two polymer dope feed slots, relative to a continuous moving coating surface; applying polymer dopes from each of the dope feed slots onto the continuously moving coating surface so as to create a multiple layer polymer dope coating on the coating surface; subjecting the multiple dope layer to contact with a phase inversion producing environment so as to form a wet multilayer phase inversion microporous membrane; and then washing and drying the membrane. Other representative apparatuses and processes are also disclosed.

Pre-metered, unsupported multilayer microporous membrane

A filter sheet is provided which comprises a self-supporting fibrous matrix having immobilized therein particulate filter aid and particulate ion exchange resin, wherein said particulate filter aid and particulate ion exchange resin are distributed substantially uniformly throughout a cross-section of said matrix. A process for removing ionic impurities from a photoresist solution is also provided which comprises passing the photoresist solution through said filter sheet to remove ionic impurities therefrom.

Filter sheet and process for purifying photoresist composition employing the filter sheet

An at least two zone, unsupported, continuous microporous membrane is disclosed. The at least two zone, unsupported, continuous microporous membrane may include at least two different membrane pore size zones or the pore sizes may have about the same pore size. Apparatus and processes for fabricating at least a two zone unsupported, continuous, microporous membrane are also disclosed. One representative process disclosed for forming a continuous, unsupported, multizone phase inversion microporous membrane having at least two zones comprises of the acts of: operatively positioning at least one dope applying apparatus, having at least two polymer dope feed slots, relative to a continuous moving coating surface; applying polymer dopes from each of the dope feed slots onto the continuously moving coating surface so as to create a multiple layer polymer dope coating on the coating surface; subjecting the multiple dope zone layer to contact with a phase inversion producing environment so as to form a wet multizone phase inversion microporous membrane; and then washing and drying the membrane. Other representative apparatuses and processes are also disclosed.

Unsupported multizone microporous membrane

Process for purifying photoresist composition employing a filter sheet

A spiral wound filter element is disclosed which includes alternating layers of filter medium and diffusion medium wrapped about a cylindrical core defining a central axis of the filter element. The alternating layers extend from a radially innermost layer of the filter element to a radially outermost layer of the filter element, the diffusion medium is defined by a continuous lengthwise sheet of mesh material, and the filter medium is defined by at least one sheet of filter material arranged along the length of the continuous sheet of mesh material. The alternating layers of filter medium and diffusion medium define three distinct radially disposed layered filtering sections surrounding the cylindrical core, and include a first filtering section having radially outer prequalifying layers, a second filtering section having middle prequalifying layers and a third filtering section having radially inner qualifying layers. The radially outer prequalifying layers and the middle prequalifying layers define about two-thirds of the radial distance from the radially outermost layer of the filter element to the radially innermost layer of the filter element.

Filter and method of filtering a fluid

A method for sealing the edges of a filter sheet (,) with wax to create a fluid-impermeable wax seal (,) enclosing a non-sealed portion (,). The method includes applying melted wax to the edges of the filter sheet, heating the treated filter sheet such that the wax permeates through the edges thereof, and then allowing the filter sheet to cool such that the wax congeals. The wax of the fluid-impermeable wax layer (,) has a durometer reading of about 75 to about 100 Shore A hardness at 25&deg; C. and 85&deg; C., a melt point of about 110&deg; C. to about 180&deg; C., a viscosity of less than about 100 cp at 155&deg; C. and preferably includes ethylene bis stearamide. The wax layer increases the useful life of the filter sheet while providing a sheet which is easily released from a filter press and which retains integrity along the seal during repeated hot water sanitations.

Method for sealing the perimeter of a filter sheet

A filter sheet positioned between plates (14) of a filter press has a fluid-impermeable wax layer (11) sealing the sheet's perimeter. The wax preferably comprises ethylene bis stearamide and has a durometer reading of about 75 to about 100 Shore A hardness at 25.degree. C. and 85.degree. C., a melt point of about 110.degree. C. to about 180.degree. C., and a viscosity of less than about 100 cp at 155.degree. C. The wax layer increases the useful life of the filter sheet while providing a sheet which is easily released from a filter press and which retains integrity along the seal during repeated hot water sanitations.

Growing community of inventors

Tolland, CT, United States of America

Richard D Sale