PATENTS

10Membrane Technology January 2003

PATENTS

PatentsProton conductor gas sensorApplicant: Figaro Engineering Inc, JapanA membrane electrode assembly contains a pro-ton conductive membrane sandwiched by metalplates, which are further sandwiched by ‘heatpressable’ films. Openings are formed in the ‘heatpressable’ film, and the metal plate, respectively,so that an electrode is used as the sensing elec-trode and exposed to the atmosphere to be mea-sured. Openings are also formed in the film andmetal plate, respectively, so that an electrode isused as the counter electrode, and water vapour issupplied to the electrode from a water pack.Patent number: WO 02/097420Inventors: T. Inoue, H. Okoshi, T. Nakahara, K.KaneyasuPublication date: 5 December 2002

Supporting substrate Applicant: Apsys Advanced Particle SystemsGmbH, GermanyThe invention relates to a supporting substrateused for the deposition, automated recognitionand spectroscopic identification of particulate con-taminants in liquid or gaseous media. The sup-porting substrate structure comprises a filter mem-brane that is made from polymer materials whichhave a defined pore width. The surface of the filtermembrane, which has a very smooth structure, iscoated with metal that does not represent anyspectral features for the spectroscopic identifica-tion in the selected wavelength range, and absorbsnone or only a small portion of the irradiated laserenergy at the selected excitation wavelength Patent number: WO 02/097400Inventors: L. Holz, O. Valet, M. LankersPublication date: 5 December 2002

Growth of filterable organisms Applicant: Biomed Diagnostics, USAThis patent covers membrane filters and methodsof trapping and culturing microorganisms. Themembrane filters trap, or filter, from a sample, aspecific microorganism of interest requiring a setof growth components. The membrane comprisesa first subset of growth components such that themicroorganism can grow and divide with themembrane contacting a medium that is made upof a second subset of growth components (definedas all components of the set of growth componentsthat are not included in the first subset). Methodsfor detecting a microorganism comprise providinga membrane filter that is composed of a first subsetof the set of growth components; passing the sam-ple through the filter; and placing the filter in con-tact with a medium comprising a second subset ofthe set of components for growth. For members ofgenus Legionella, a filter impregnated with activat-ed charcoal may be employed for detection andculturing.

Patent number: WO 02/097052Inventors: J.H. Hall, K. Borchardt, R.D. Hall Publication date: 5 December 2002

Tubular membranesApplicant: Pall Corp, USAAn improved tubular membrane, and process ofmaking it, are disclosed by this patent. Essentially,the process involves depositing fine metallic fibreonto a substrate. The deposited fibres are heatedto form a flexible membrane. Catalytically activeparticles can be dispersed within the fine metallicfibres. The flexible membrane is wound to formwhat is referred to as a ‘membrane winding’, andthis structure is then sintered to form a substan-tially rigid tubular membrane.Patent number: WO 02/096538Inventors: N.R. Quick, M.C. Murray, M.R.June, T. Peloguin Publication date: 5 December 2002

Electrochemical cell productionApplicant: Accentus Plc, UKA lithium ion polymer cell comprises an anodelayer and a cathode layer each comprising respec-tive lithium ion insertion materials, separated by aporous polymeric membrane, in which the anodelayer and the cathode layer each incorporates apolymeric binder. The cell is made by coating athin porous layer of a copolymer material onto theface of the anode layer and onto the face of thecathode layer (before assembling the anode layer).The porous polymeric membrane and the cathodelayer are formed into cell assembly, and this is con-tained by an enclosure. A small quantity of a liq-uid, such as acetone, is introduced into the enclo-sure, this being a solvating liquid for thecopolymer material but not for the polymericmaterial of the membrane. The temperature isheld at a slightly elevated level – at about 30°C – sothe surfaces of the thin porous copolymer layersbecome tacky and adhere to the membrane. Thesolvating liquid can then be evaporated from thecell assembly, and an electrolyte solution intro-duced into the cell assembly to form a cell. Thistechnique enables the cell components to be lami-nated without requiring the application of pres-sure, and it enables very thin membranes to beused, which are of low resistance.Patent number: WO 02/099920Inventors: F. Coowar, V. DassPublication date: 12 December 2002

Modified microporous membrane Applicant: Cuno Inc, USADisclosed is a multi-layered, composite microp-orous membrane. Its structure comprises at leastone layer with a highly electropositivehydrophilic material distributed throughout.The material is capable of irreversibly bindingnucleic acid. Optionally, it also includes at leastone layer where the material is associated withsequence-specific peptide nucleic acids, permit-ting the simultaneous or sequential capture,amplification and/or identification of specific

nucleic acid sequences of interest. Also detailedby the patent are methods of use of the compos-ite membranes of the invention in applicationsbased on the sequence-specific capture and/oramplification and identification of nucleic acidfrom complex biological samples.Patent number: WO 02/099139Inventors: T.E. Arnold, M.T. Meyering, R.S.Chesterson Publication date: 12 December 2002

Dialysis machine Applicant: Gambro Lundia AB, SwedenA dialysis machine is described. It has a dialysatecircuit; a blood circuit; a filter that has a dialysatecompartment connected to the dialysate circuit;a blood compartment that is connected to theblood circuit; and a semipermeable membranethat is positioned in such a way that it separatesthe dialysate compartment from the blood com-partment. A method of filling and washing thefilter comprises the recirculation of a physiologi-cal saline in the dialysate circuit and the transferof the physiological saline from the dialysate cir-cuit to the blood circuit through the semiperme-able membrane.Patent number: WO 02/098491Inventor: P. Rovatti, P. PirazzoliPublication date: 12 December 2002

Recirculating tangential separationsystemApplicant/Inventor: B.D. GrayA method of separating a mixture into a numberof more concentrated products, using recircula-tion and concentration of one product, so as toextract a substantially large fraction of anotherproduct from the mixture is described by thispatent. The apparatus that uses this method is alsodetailed. This can be a system, such as a reverseosmosis (RO) unit that is capable of high recoveryrates, efficient power usage, and long componentlife. Substantially 100% of the concentrate prod-uct exiting a tangential separation device (such asan RO filtering device) recirculates until the con-centration of the concentrate reaches a predeter-mined level, at which time it is purged from thesystem and a new cycle begins. This achievesrecovery rates in RO-based water purification sys-tems from around 70% for feed water with 1000ppm of total dissolved solids, to around 97% forfeed water with 100 ppm of total dissolved solids.The method and apparatus also provide for auto-mated cleaning and maintenance of the separa-tion and filtration elements, which optimizes theservice life of the components.Patent number: WO 02/098527Publication date: 12 December 2002

Composite membrane manufactureAssignee: Lynntech Inc, USAThis invention relates to methods of fabricatingcomposite membranes in which at least one ofthe components is initially provided in the form of a precursor. The composite material