Cuno, Inc.

Norton Company

Amf Gmbh

George T Emond

Kenneth C Hou

Eugene A Ostreicher

Joseph V Fiore

Rodney A Knight

Chaokang Chu

Robert G Barnes

Asit K Roy

Shih Yee Kuo

Cristan Ellison-Hayashi

A method of removing material from a surface comprising abrading a surface comprising the step of abrading a surface with an abrasive tool or an abrasive powder comprising a boron suboxide (BxO) composition, wherein during the abrading step the boron suboxide (BxO) composition is maintained at low temperatures. The abrasive which is from the boron suboxide (BxO) family of compounds exhibits an unexpectedly high quality of abrading comparable with the highest quality particulate natural and synthetic diamond, which has a hardness about double that of the boron suboxide (BxO) of the present invention. Further, the invention includes a lapping and polishing powder and lapping slurry wherein the powder is made from a dense, finely crystalline boron suboxide material with a Knoop hardness KHN.sub.100 of at least about 2800 kg/mm.sup.2 and preferably at least 3800 kg/mm.sup.2.

Method of abrading with boron suboxide (BxO) and the boron suboxide

A cationic charge modified microporous membrane is provided. The membrane comprises a hydrophilic organic polymeric microporous membrane having bonded thereto, through a cross-linking agent, a charge modifying amount of a cationic charge modifying agent. The charge modifying agent is an aliphatic amine or polyamine, preferably tetraethylene pentamine, and the cross-linking agent is an aliphatic polyepoxide having a molecular weight of less than about 500, preferably 1, 4 butanediol diglycidyl ether. The microporous membrane is preferably nylon. The process for applying the charge modifying agent to the membrane, preferably comprises contacting the membrane with an aqueous solution of the charge modifying agent and then contacting the membrane with a substantially aqueous solution of the cross-linking agent. The preferred process uses high purity water, i.e. water having no significant ionic content, to produce a membrane suitable for use in filtering ultra pure (18 megohm-cm resistivity) water for use in producing electronic devices. Such a membrane exhibits an advantageously low 'flush-out' time compared to known cationic charge modified microporous membranes and unmodified microporous membranes.

Process for charge modifying a microporous membrane

Charge modified microporous membrane

A process is provided for for cationically charge modifying a microporous filter membrane, wherein the membrane is a substantially symmetrical isotropic, hydrophilic, organic polymeric microporous filter membrane, preferably nylon, having a microstructure throughout the membrane. The process comprises bonding a primary charge modifying amount of a water soluble cationic charge modifying agent to substantially all of the membrane microstructure, without substantial pore size reduction or pore blockage. The charge modifying agent is a reaction product of a polyamine with epichlorohydrin, the reactive product having (i) tertiary amine or quaternary ammonium groups, and (ii) epoxide groups along a polyamine chain, the epoxide groups capable of bonding to the microstructure of the membrane.

Process for charge modifying a microphorous membrane

A cationic charge modified microporous membrane comprising a hydrophilic organic polymeric microporous membrane and a cationic charge modifying agent bonded to substantially all of the wetted surfaces of the membrane, the charge modifying agent being an epichlorohydrin modified polyamide having tertiary amine or quaternary ammonium groups. A secondary charge modifying agent may be employed selected from: (i) aliphatic polyamines having at least one primary amine or at least two secondary amines; and (ii) aliphatic amines having at least one secondary amine and a carboxyl or hydroxyl substituent. Processes for producing and using the membrane are also described.

Liquid filtration using hydrophilic cationic isotropic microporous nylon

A cationic charge modified microporous membrane, process for producing said membrane and use thereof are provided. The membrane comprises a hydrophilic organic polymeric microporous membrane and a charge modifying amount of a primary cationic charge modifying agent bonded to substantially all of the wetted surfaces of the membrane. The primary charge modifying agent if a water soluble organic polymer having a molecular weight greater than about 1000 wherein each monomer thereof has at least one epoxide group capable of bonding to the surface of the membrane and at least one tertiary amine or quaternary ammonium group. Preferably, a portion of the epoxy groups on the organic polymer are bonded to a secondary charge modifying agent selected from the group consisting of:

Charge modified microporous membrane, process for charge modifying said

A cationic charge modified microporous membrane is provided. The membrane comrises a hydrophilic organic polymeric microporous membrane having bonded thereto, through a cross-linking agent, a charge modifying amount of a cationic charge modifying agent. The charge modifying agent is an aliphatic amine or polyamine, preferably tetraethylene pentamine, and the cross-linking agent is an aliphatic polyepoxide having a molecular weight of less than about 500, preferably 1, 4 butanediol diglycidyl ether. The microporous membrane is preferably nylon. The process for applying the charge modifying agent to the membrane, preferably comprises contacting the membrane with an aqueous solution of the charge modifying agent and then contacting the membrane with a substantially aqueous solution of the cross-linking agent. The preferred process uses high purity water, i.e. water having no significant ionic content, to produce a membrane suitable for use in filtering ultra pure (18 megohm-cm resistivity) water for use in producing electronic devices. Such a membrane exhibits an advantageously low 'flush-out' time compared to known cationic charge modified microporous membranes and unmodified microporous membranes.

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Southington, CT, United States of America

George T Emond