Cuno, Inc.

Amf Gmbh

Other

Eugene A Ostreicher

Kenneth C Hou

Richard D Sale

Joseph V Fiore

George T Emond

Rodney A Knight

Joseph R Infantino

Mark T Meyering

Robert G Barnes

John L Pulek

Paul J Marinaccio

Rita J Andreoli

Arto Artinyan

Richard S Chesterson

Nils L Dailey

Alvin L Crowder, Iii

Murtaza Amin

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 improved combination non-luminescent microporous membrane and solid support for use in micro-analytical diagnostic applications is disclosed. Specifically, composite microarray non-luminescent slides having a microporous membrane effectively attached by covalent bonding through a surface treatment to a substrate that prepares the substrate to sufficiently, covalently bond to the non-luminescent microporous membrane formed by a phase inversion process such that the combination produced thereby is useful in microarray applications and wherein the porous non-luminescent nylon composite microarray slides are covalently bonded to a solid base member, such as, for example, a glass or Mylar microscope slide, such that the combination produced thereby is useful in microarray applications. Apparatus and methods for fabricating lithe non-luminescent composite microarray slides are also disclosed.

Low fluorescence nylon/glass composites for micro-analytical diagnostic applications

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

Filter sheet for purifying photoresist composition

A compressible differential pressure energized seal (18) coacting between a filter element (10) and the like and a housing (21) comprises a compressible portion (35) having a large open end (36) and a small open end (37), the large end (36) directed toward and contacting the housing (21 ) and the small end (37) directed toward the filter (10) element; and an annular flange (38) integrally attached to the compressible portion (35) at its small end (37) and extending outwardly, the flange (38) operatively communicating with the filter element (10). The seal (18) may also include at least one flap (43) to center the filter element (10) to which it is attached onto a centering rod (31 ) carried within the housing (21 ). Such a seal (18) is compressed when the element (10) is operationally enclosed within the housing (21 ) to provide a leak-proof seal during operation and is self-energizing during operation such that as the differential pressure increases, it more forcefully engages the sealing surface.

Compressible differential pressure energized seals for filter elements

A process for removing anionic contaminants from an aqueous fluid having a pH up to about 12, the fluid being passed through a filter media whereby the contaminants are electrokinetically captured and adsorbed onto the media, such a media comprising cellulose fiber and silica based particulate or fiber filter elements and a charge modifying amount of a cationic charge modifying system bonded to the surfaces thereof. One component of the charge modifying system is a primary charge modifying agent characterized as a water soluble organic polymer capable of being adsorbed into the filter elements and having a molecular weight greater than about 1000. Each monomer of the polymer can have at least one epoxide group capable of bonding to the surface of the filter elements and at least one quaternary ammonium group. A portion of the epoxy groups on the organic polymer are bonded to the secondary charge modifying agent.

Use of cationic charge modified filter media

A process for removing particulate contaminants from a fluid is disclosed, the fluid being passed through a filter media comprising cellulose fiber and silica based particulate or fiber filter elements and a charge modifying amount of a cationic charge modifying system bonded to the surfaces thereof. One component of the charge modifying system is a primary charge modifying agent characterized as a water soluble organic polymer capable of being adsorbed into the filter elements and having a molecular weight greater than about 1000. Each monomer of the polymer can have at least one epoxide group capable of bonding to the surface of the filter elements and at least one quaternary ammonium group. A portion of the epoxy groups on the organic polymer are bonded to the secondary charge modifying agent.

A filter element adapted to be sealingly clamped in a filter housing. The element comprises a porous hollow cylindrical integral self-supporting bonded fibrous structure. The structure has thermally melt bonded to at least one end thereof, a thermoplastic polymer closed cell foam sealing gasket. The gasket is adapted to provide a sealing surface between the end of the cartridge and the sealing edge of the filter housing. In a preferred embodiment, the sealing edges of the filter housing used in conjunction with the aforedescribed filter element comprises at least two circular sealing edges concentric to the axis of the cylindrical filter element. Such a combination provides a means for determining whether there is leakage past the sealing edges by the discoloration of the sealing gasket area between the concentric sealing edges by the liquid being filtered.

Filter element

A filter element adapted to be sealingly clamped in a filter housing. The element comprises a porous hollow cylindrical integral self-supporting bonded fibrous structure. The structure has thermally melt bonded to at least one end thereof, a thermoplastic polymer closed cell foam sealing gasket. The gasket is adapted to provide a sealing surface between the end of the cartridge and the sealing edge of the filter housing. In a preferred embodiment, the sealing edges of the filter housing used in conjunction with the aforedescribed filter element comprises at least two circular sealing edges concentric to the axis of the cylinder filter element. Such a combination provides a means for determining whether there is leakage past the sealing edges by the discoloration of the sealing gasket area between the concentric sealing edge by the liquid being filtered.

The media comprises cellulosic fiber and silica based particulate or fiber filter elements and a charge modifying amount of a cationic charge modifying system bonded to the surfaces thereof. A component of the charge modifying system is a primary charge modifying agent characterized as a water soluble organic polymer capable of being adsorbed into the filter elements and having a molecular weight greater than about 1000. Each monomer of the polymer can have at least one epoxide group capable of bonding to the surface of the filter elements and at least one quaternary ammonium group. Preferably, the primary charge modifying agent is a polyamido-polyamine epichlorohydrin resin, a polyamine epichlorohydrin resin, or a resin based upon diallylnitrogen-containing materials reacted with epichlorohydrin. A portion of the epoxy groups on the organic polymer are bonded to the secondary charge modifying agent. This secondary charge modifying agent is an aliphatic polyamine having at least one primary amine or at least two secondary amines.

Cationic charge modified filter media

A filter element comprising a hydrophilic organic polymeric microporous filter membrane having a preformed substantially non-porous sealing area and a filter housing having, preferably, a hydrophobic thermoplastic sealing surface in thermoplastic sealing relationship with the sealing area. Preferably, the filter membrane is a pleated cylindrical membrane and the housing includes endcaps thereto. The preferred membrane is nylon. The preferred pleated cylindrical membrane is produced from an elongated porous filtration area longitudinally bordered by substantially non-porous sealing areas. Such a membrane may be produced by a specific casting method or collapsing the pores along the longitudinal borders of the filtration area. The filter element is particularly useful for the filtration of aqueous liquids, particularly parenteral or body liquids.

Filter element having microporous membrane

A filter media sheet comprising fine particulate and a self-bonding matrix of cellulose fiber, the surfaces of at least one of which are modified with a polyamido-polyamine epichlorhydrin cationic resin, the matrix incorporating beaten cellulose fiber to provide a Canadian Standard Freeness of less than 600 ml.

Growing community of inventors

Farmington, CT, United States of America

Eugene A Ostreicher