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Journal Archive

Platinum Metals Rev., 1990, 34, (1), 49

NEW PATENTS: January 1990



Fine Grained Tungsten Heavy Alloys for Armour Penetration

gte products corp. European Appl. 323,628A

A W heavy alloy contains 88-98 wt.% W, 0.25-1.5 wt.% Ru and/or Re as grain refiners, with balance Ni and Fe in a Ni:Fe wt. ratio of 1:1 to 9:1. The alloy has more than 2500 grains/mm2 as determined from the microstructure. The alloys are used as armour penetrators, and have a finer grain structure than previously available which improves ballistic performance.

Corrosion Resistant Amorphous Alloy

standard oil co. (ohio) U.S. Patent 4,810,314

An amorphous alloy contains Cr (0.69-0.96), one or more of Pt, Pd, Rh, Ir and Ru (up to 0.01), and one or more of P, B, N, C, As, Sb or S (0.04-0.40), and may be formed by deposition as a film on a substrate. The alloy has excellent corrosion resistance to both strongly oxidising and reducing environments, and is used for cladding on reaction vessels, pumps, pipelines for corrosive chemicals, and for coating structures exposed to sea water.

Articles of Oxide Dispersion-Strengthened Platinum

ppg industries inc. U.S. Patent 4,819,859

Articles of oxide dispersion-strengthened Pt are made from a relatively thick mass of Pt or Pt alloy having a minor oxide phase dispersed in it. The method involves working the mass to a thin layer, superimposing several worked layers with offset joints, and bonding the layers below the melting point by hammer welding. An article laminated substantially throughout its extent is formed.

Composite for Resistance Coating Film

sumitomo metal mini. k.k. Japanese Appl. 1/59,802

A composite used for resistant film having a small thermal expansion coefficient includes 8-60 wt.% of Ru oxide powder, less than 52 wt.% of ceramic powder, and 40-80 wt.% of glass powder generating a crystalline phase during sintering at 750-900°C. The composite can be effectively used for resistance coating film for a ceramic base of low thermal expansion coefficient.

Corrosion Resistant Amorphous Stainless Alloy

nippon teleg. & teleph. Japanese Appl. 1/79,343

An amorphous stainless alloy contains at least 5 at.% Au+Pt, 3-10 at.% Cr, 0-30 at.% Si, 0-30 at.% B, with 15-30 at.% Si+B, and balance Fe. The stainless alloy has good mechanical characteristics, improved corrosion resistance of Fe-Cr-Si-B amorphous alloy, and is used in sea water without corrosion protection.

Platinum Flakes Production

kawatetsu techno, re. Japanese Appl. 1/92,303

A Pt powder and a sintering of Ti (alloy) are milled together with a solvent such as alcohol and/or an additive such as an alkoxide. The shape of the Ti-flake is controlled by the amount of solvent and/or additive. The flakes are used for providing plastics with electroconductivity, for reinforcing, electromagnetic shields, colouring, and so on.

Fine-Grained Powder of Silver-Palladium Composite

tanaka kikinzoku kogyo Japanese Appl. 1/100,203

A composite powder consisting of uniformly dispersed Pd in fine-grained Ag is prepared by a chemical or H2 reduction reaction, and is then heat treated at 200-500°C. Production provides a paste which enables formation of Ag-Pd film in which Pd is uniformly dispersed.

Production of Strengthened Platinum Material

tanaka kikinzoku kogyo Japanese Appl. 1/142,059

A strengthened Pt material is made by crossing Pt or Pt based alloy wire material to laminate in several layers, and butt welding the laminate to form a sheet material. The material is used for making the stock of crucibles for melting optical glass and for physical chemistry, having high strength in the rolling direction and the lateral direction.


Electrolytic Removal of Thermally Stable Salts

dow chemical co. U.S. Patent 4,814,051

An alkanolamine sorbent conditioning process for removing acid gases from gas streams using an absorber and a thermal regenerator produces heat-stable salts of alkanolamines. The process is improved by treating a side stream of the solution from thermal regeneration in electrochemical cells having Ir oxide coated anodes, to destroy these salts. Improved electrode materials give higher current densities and greater durability.

Apparatus for Manufacturing Peroxide Electrolytically

agency of ind. sci. tech. Japanese Appl. 1/42,590

Manufacturing peroxide or MHO2 (M=alkali metals or H) is achieved by reducing O2 electrochemically on the surface of the cathode of an electrolytic cell in which a cation exchange membrane is cemented on the surface of an anode opposed to the cathode. In an example H2O2 was produced in a cell having a cation exchange membrane and an anode with a duplex coating layer of Pt and Ir.

Resin Moulded Electrode for Electrolysis

japan carlit k.k. Japanese Appl. 1/132,789

A resin moulded electrode is prepared by coating at least one of Pt, Rh, Ir, Ru and their oxides on the surface of valve metal oxide particles, applying these conductive particles on the surface of thermoplastic resin particles, drying, and hot compacting to form an electrically conductive layer. The insoluble electrodes are used for example for electrolytic manufacture of persulphates, and have low cost and long life.

Durable Anodes for Electrolysis of Alkali Chlorides

h. debrodt German Appl. 3,737,235

Anodes for electrolysis of alkali chlorides, for example in membrane cells, are produced by coating a Ti substrate with solutions of at least one Pt metal salt and one or more other metal salts, thermally decomposing the salts, and repeating to form an active layer of several partial layers. The use of different Ti salts gives layers of graded morphology which adhere well, are durable, and have a high 02 overvoltage.

Hardening Treatment of Palladium Articles

f. n. berseneva Russian Patent 1,435,654

Pd articles are hardened more efficiently by electrolytic hydrogenation in aqueous 4% NaF, with cathodic polarisation using an optimum current density of 9 A/dm: for 5-20 min, followed by anodic H desorption under the same conditions for the same time, then repeating the cycle several times. Pd articles such as the elements of diffusion filters are hardened, and increased strength of the product is achieved.


Palladium Catalyst Used in Electroless Plating

omi int. corp. European Appl. 317,092A

A complex consisting of X Pd atoms and Y N-containing ligands where X:Y is at least 1, is used in an electroless plating process. The process involves cleaning and/or conditioning the substrate, rinsing, optionally etching, contacting with the Pd containing catalyst composition, contacting with a reducing agent, and electroless plating the substrate.

Anti-Foulant and Marine-Foulant Release Coating

general electric co. European Appl. 320,716A

An outer coating for a hull is a curable silicone rubber composition consisting of 100 parts of a liquid vinyl chain-stopped polysiloxane, 20-50 parts of an organopolysiloxane copolymer, 1-200 parts of inorganic filler, a Pt catalyst, and a liquid organohydrogen polysiloxane. The composition is useful as an anti-foulant and marine-foulant release coating, and has excellent adhesion to the substrate.

Forming Adherent Hard Coatings on Titanium Alloys

air products & chem. inc. European Appl. 322,812A

A Ti alloy substrate has a 0.5-15 μm interlayer of non-reactive noble metal selected from Pt, Pd, Rh, Ir, Au, Ag, Co or Cu applied by electroless plating, over which is a hard coating of ceramic, hard metal, hard metal compound or diamond-like C. The interlayer provides good adhesion of the hard outer layer, and is deposited without heating the substrate to 540-800°C which results in deterioration of mechanical properties.

Composite Electroplated Coatings for Iron-Base Alloys

electro alloys corp. U.S. Patent 4,835,067

A metal component consists of a corrodible Fe-base alloy substrate with three electroplated layers. The base and final layers are Pt, Pd, Au, Ag or their alloys, preferably Au at least 10 punch thick, with a single intermediate layer of Ni or a Ni-base alloy, 50-350 μinch thick. The coatings are used for sealing covers for semiconductor packages, and have good resistance to corrosion and blistering.

Palladium Layer for Copper Plating a Substrate

nippon denso k.k. Japanese Appl. 1/79,379

A substrate for Cu plating has a layer of Pd particles and/or a layer of W formed before plating. The plating process involves forming a first layer by plating with a solution containing a first complexing agent, a Cu salt and a reducing agent, and then forming a second layer in the same way but using trialkenolamine as the second complexing agent. Using this method a Cu layer of uniform thickness is formed.

Selective Plating Techniques

seiko denshi kogyo k.k. Japanese Appls. 1/96,383-84

Selective plating on a transparent conductive film pattern, formed for example on a glass substrate of a liquid crystal panel, is achieved by (a) anodic electrolysis in a liquid with Pd as the catalyst to be precipitated, prior to electroless plating, or (b) anodic electrolysis in film-activating liquid, immersion in a solution with Pd as catalyst, then electroless plating. Damage of the glass substrate by immersion in fluoride-containing active liquid is avoided.

Black-Rhodium Plating for Electric Razor Outer Blade

kyushu hitachi maxe. Japanese Appl. 1/101,993

The outer blade of an electric razor is formed by electroforming Ni or Ni-Co alloy, black-Rh plating using a plating bath with Rh sulphate or phosphate and aromatic sulphonic acid or an organic carboxylic acid, then anodic electrolysis, and annealing at 100-200°C. High quality blades which can be safely used for long periods are obtained.

Production of Adherent Nickel Coatings

aeg olympia a.g. German Appl. 3,732,510

Adherent Ni coatings are produced on smooth or rough glass or ceramic plates by a method which includes coating the substrate surfaces with a thin uniform layer of phosphate lacquer, heating to form a Ni phosphide bonding coat, depositing Pd seeds, and then chemically depositing Ni. The low cost process gives a high level of adherence and good thermal properties, and the coated plates are used in the manufacture of ink-jet heads.

Electrolyte for Palladium-Nickel Alloy Coatings

veb. mikroel pieck East German Patents 264,462-63

An electrolyte for producing functional and decorative Pd-Ni alloy coatings on Ni, Fe, Cu or alloys contains an aqueous solution of 1-200 g/1 Pd(NH3)4(NO3)2, 1-200 g/1 Ni(NO3)2 and/or Ni(NH3)4(NO3)2, and 20-200 g/1 NH4NO3. The electrolyte is used at a pH of 7.5-10.5, 15-80°C and a current density of 0.1-10 A/dm2. A bright, ductile, wear and corrosion resistant, crack and pore-free coating is produced using an electrolyte free from organic brightening agents.


Platinum Igniting Element for Cigarette Lighter

tdk corp. European Appl. 318,215A

A cigarette lighter has an igniting element which is a coil made of Pt wire or wire of a Pt based material; the wire of 0.10-0.25 mm diameter, and the pitch of the coil not exceeding 1 mm. The element is mounted near the fuel gas nozzle, and provides a combustion-promoting member made from heat-resistant material, so that burning of the fuel gas can be smoothly contained.

Temperature Sensitive Gas Detector

siemens a.g. European Appl. 321,785A

A bipolar transistor covered with a 100-150 nm thick Pt or Pd catalyst film is used in the detection of a gas, and shows a temperature rise due to an exothermic catalytic reaction at the surface of the film. The catalyst is heated by the power dissipation of the transistor acting as a sensor or by that of a similar heating transistor. Very litde space is taken up by the integrated semiconductor sensor and heating element.

Thermal Effect Fluid Flow Detector

rosemount eng. co. World Appl. 89/3,512A

A thermal effect sensing device has a semiconductor substrate supporting an insulating layer which has a thin film of Pt deposited on it. The Pt film is shaped to provide a serpentine resistive element which is suspended over one of the holes etched through the substrate and insulating layer. The sensor is of reduced size and detects thermal properties of a fluid and is used for ventilation and engine intake flows.

Self Referencing Solid Electrolyte Sensor

westinghouse elec corp. U.S. Patent 4,828,672

A sensor to monitor SO2, CO2 or NO2 plus O2, for example in stack gas, has a solid electrolyte in contact with a monitor electrode exposed to a test gas and a Pt reference electrode isolated from the gas. Different electrolytes are used which dissociate to supply a reference gas at the reference electrode, corresponding to the component to be measured. The sensor can be miniaturised and has low manufacturing and operative costs.

Pure Platinum Ultrafine Wire Material

tanaka kikinzoku kogyo Japanese Appl. 1/39,335

Pure Pt ultrafine wire material is obtained by adding 10-3000 wt. ppm in total of at least one of Pd, Rh, Ir, Os, Ru, Au, Ag, Cu, Al, Y, Ni, Co, Ti, W, Si, Zr and Ca to pure Pt. The material is used for making ultrafine wires for sensors or medical appliances, having improved mechanical properties, and with breakage in drawing prevented.

Chemical Sensor with Porous Platinum Electrode

japan storage battery Japanese Appl. 1/47,941

A chemical sensor is made by laminating together a thin film electrolyte such as Ag, a porous detector electrode of, for example, Pt, and a permeation membrane. The sensor is used for detection of oxidised or reduced materials in gas or liquid, such as O2, H2 or SO2. The membrane and electrode are supported by the thin film electrolyte with high mechanical strength and conductivity, so maintenance is easy and the equipment is compact.

Metallic Casting Mould

furuya kinzoku k.k. Japanese Appls. 1/48,637 and 1/48,655

A metallic casting mould consists of a male and a female mould block, one or both of which are made of dispersion hardened Ir, Ir alloy, Pt or Pt alloy, in which 0.01-5 wt.% of metal oxide particles of grain size <0.1 μnm are evenly dispersed. The dispersion hardened Ir alloy contains 0-50 wt.% of Pt, Pd, Rh, Os, Ru, Au, Re, W and so on, while the dispersion hardened Pt alloy may contain 5-30 wt.% Rh. The mould is used for casting metal melting at 600-1650°C, and has good thermal and mechanical properties.

Oxygen Electrode for Automatic Production

omron tateisi eltrn. K.K.Japanese Appl. 1/54,346

An O2 electrode has an insulating base with at least 2 electrodes being a Pt working and a Ag reference electrode formed in parallel on one surface, with sensitive portions (such as Ag chloride film at the reference electrode) of specific area ratio, and an insulating protective film. The O2 electrode has stabilised output, gives measurements with high accuracy and little noise, and can be mass produced so cost is reduced.

Portable Oxygen Sensor with Platinum Electrodes

riken corp. Japanese Appl. 1/78,149

A portable O2 sensor consists of a base plate having O ion conducting ZrO2 solid electrolyte, with a pair of porous Pt electrode layers formed on either face of the plate, and a spacer and sealing plate for hermetically sealing one of the electrode layers. The sensor detects O2 shortage in construction work sites and tanks, at low temperatures, and is stable, readily controllable, compact and highly effective.

Spectroscopic Device for Optical System

nec. corp. Japanese Appls. 1/81,907/909

A spectroscopic device with improved productivity consists of a substrate on which Rh or Os and LiF are alternately laminated to construct a periodic structure. The thickness of each membrane is >1 atom and <400 Å, and the ratio of the Rh/Os:LiF membrane is 0.1-10. The device has high intensity and suitable resolving power, and can be applied for UV-ray or X-ray processing of less than 200 Å, including X-ray lithography.

Oxygen Sensor with Platinum Catalyst Layer

japan elec control sys. Japanese Appls. 1/83,149-51

An O2 sensor for an internal combustion engine has a solid electrolyte base material having O ion conductivity, electrodes formed on part of the inner and outer surfaces, a Pt catalyst layer deposited on part of the outer surface, a NOx reducing substance mixed in or coated on the Pt catalyst layer, and an optional protection layer. The air.fiiel ratio is stabilised in the region of the theoretical ratio, so surge of the car is prevented and purification by the catalyst is increased.

Platinum Wire Coil Used in Gas Leakage Alarm Unit

fuji electric mfg. k.k. Japanese Appl. 1/109,253

A gas detecting device used as a gas leakage alarm unit includes a Pt wire coil, which is moulded in a spherical shape, coated with oxide catalyst-loaded Al2O3, and then sintered. The Pt wire coil touches internally the virtual sphere of slightly smaller diameter than that of the spherical A12O3. Isopycnic distribution of the coil on the virtual sphere minimises input power, which increases the life of the device.

Oxygen Sensor with Electroconductive Layer

terumo corp. Japanese Appl. 1/112,148

An O2 sensor consists of an electroconductive layer of Pd oxide, Ir oxide or Ru oxide produced at the ion-sensitive portion of a joint type field effect transistor (FET), and a layer of fixed enzyme covering the electroconductive layer. The sensor is capable of analysing low concentrations such as 1-100 mg/dl, and has excellent noise characteristics at low frequencies.

Clad Receptacles for Crucibles

tanaka kikinzoku kogyo Japanese Appls. 1/132,747-55

Clad receptacles consist of W, Ta, Mo or their alloys coated with Pt, Rh, Ir or their alloys in which oxide is dispersed. The receptacles are used for crucibles for melting high-temperature glass or ores containing metal oxide, trays and boats for vapour deposition, and have good consumption resistance and long life.

Sensitive Element for Ethanol Vapour Determination

moscow meat dairy inst. Russian Patent 1,427,275

A process for determining ethanol vapour content in air uses a heated thermochemical sensitive element based on a Pt catalyst. To improve performance the element is kept at 118-122°C, and an electric field is generated, with measurement of the number of ethyl alcohol ions formed. The process increases sensitivity and selectivity.


Soldering an Electronic Chip to a Heat Sink

u.s. sec of air force U.S. Patent 4,817,854

Solder bonding an AlGaAs LED chip to a Cu or BeO heat sink involves depositing a layer of Ni or Ti on the sink, followed by a layer of Pt at least 1500 Åthick, annealing at 450-475°C in a partial vacuum containing H2, depositing a wetting layer of Au and a layer of In, and soldering using a flux-free soldering process. The annealed Pt layer is very dense, stable and free of microporosity, and so functions effectively as a migration barrier.


Platinum Catalyst Free of Ionic Platinum for Paraffin Production

shell int. res. mij. b.v. British Appl. 2, 211, 756A

Paraffins are produced by hydrodecyclisation of naphthenes using a catalyst of metallic Pt on an Al2O3 support, which has been extracted with a solvent to remove ionic Pt before use. This increases catalyst selectivity for paraffins with the same number of C atoms as the naphthenes, while decreasing selectivity for those with fewer C atoms.

Platinum Catalyst for Production of Hydroxylammonium Salts

sumitomo chem. ind. k.k. European Appl. 308,719A

A catalyst for NO reduction consists of 0.01-10 wt.% Pt, optionally with an alkali metal sulphide at S:Pt atomic ratio of 0.05-1, on a graphite, charcoal, SiO2 or Al2O3 support. Preparation involves reduction of a Pt compound with thiosulphate, at 50-150°C. The catalyst gives improved selectivity for production of hydroxylammonium salts by reduction of NO with H2, thereby improving the safety of the process.

Carbon Monoxide Oxidation Catalyst

phillips petroleum co. European Appl. 311,084A

A catalyst composition is prepared by impregnating a monolith support with a colloidal dispersion of SnO2, drying, treating with a solution of Pt and/or Pd compounds plus a Cr compound, drying to form the oxides and Pt and/or Pd metals, and activating in a reducing atmosphere. The catalyst is used for low temperature (0-400°C oxidation of CO to CO2, in engine exhaust gas, breathing masks or in lasers.

Dual Phase Catalytic Converter with Extended Life

soc. fr. prod, catalyse European Appl. 313,434A

A catalytic converter consists of a monolithic support with a porous coating, absorbed Rh, Ni, Fe, Zr, V, Cr, Ce or others, and each end impregnated with a primary or secondary catalytic phase, having at least one of the above metals and at least one of Pt, Pd, Rh or Ir. By using two different phases an extended life is obtained for the converters in treatment of exhaust gases from petrol and diesel I.C. engines.

Platinum or Rhodium Free Three-Way Catalysts

degussa a.g. European Appls. 314,057-58A

Three-way catalysts used for conversion of CO, hydrocarbons and NOx in I.C. engine exhaust gases consist of either (a) 0.03-3 wt.% Pd and Pt in wt. ratio 0.1-10:1, or (b) 0.03-3 wt.% Pd and Rh in wt. ratio 1-20:1, plus CeO2 applied onto transitional A12O3. The CeO2 is present at 5-20 wt.% when the Al2O3 is in bulk form, and 25-50 wt.% when the A12O3 is present as a coating on a support. The high CeO2 content allows expensive Pt or Rh to be omitted while maintaining capacity for NOx reduction.

Three-Way Catalyst System with Suppressed Hydrogen Sulphide Formation

engelhard corp. European Appl. 315,402A

Internal combustion engine exhaust gas is fed to a duct containing (a) a three-way catalyst with Pt, Rh and optionally Pd dispersed on A12O3 support particles, on a monolithic substrate, to convert hydrocarbons, CO and NOx, and (b) CuO, MnO, NiO or Fe3O4 dispersed on A12O3 on a monolithic substrate to suppress H2S formed by (a). Almost total H2S suppression is obtained, particularly with CuO, and there is no interaction between (a) and (b).

Catalyst for Oxidation of Diesel Exhaust Particles

nippon shokubai kagaku European Appl. 315,896A

An exhaust purification catalyst consists of a 3-dimensional structure on which are deposited 3-300 g/1 of a refractory inorganic oxide or a zeolite, 0.1-20 g/1 of Pd, 1-50 g/1 of an oxide of Pr, Nd and/or Sm, and an oxide of Ce and/or La may be present. The catalyst is used for selective oxidation of fine carbonaceous particles from diesel engine exhaust gas, is durable, heat-resistant, and has increased purifying power at low temperature.

Novel Catalyst Composition for Hydrocarbon Reforming

british petroleum plc European Appl. 317,103A

A novel catalyst for hydrocarbon reforming consists of 0.05-2.0 wt.% Re+Pt with a Re:Pt ratio of 2:1-1:2, 0.02-0.5 wt.% Ga, 0.3-2.0 wt.% of a Group IIA metal, especially Mg, 0.1-2.0 wt.% Cl, and optionally 0.02-0.5 wt.% S, supported on A12O3. The octane number of a hydrocarbon feedstock such as naphtha is increased by passing over the catalyst at elevated temperature and pressure, for example 100-650°C and up to 50 bar.

Hydrogenation Catalysts for Jojoba and Castor Oils

council scie. ind. res. European Appl. 320,546A

The catalysts consist of a Pt group metal halide complex MXn, where n is 1-4, and a donor substituted phosphine or arsine ligand, in the matrix of a clay. Hydrogenation is at 20-45°C, 0.4-1 atm, with a catalyst:substrate wt. ratio of 1:100-500. The catalysts undergo changes in oxidation state easily, are inexpensive and readily separated.

Palladium Catalyst for Hydrogenation of Olefin Impurities

dow chemical co. World Appl. 89/2.424A

An aromatic liquid containing olefins, especially a benzene effluent, undergoes fractional distillation to increase the purity before passing, with H2, over a hydrogenation catalyst consisting of 0.05-1 wt.% Pd on Al203. Hydrogenation is at 20-130°C and 30-100 psig, so that olefins are hydrogenated to paraffins, but little aromatic liquid is hydrogenated. An aromatic liquid with acid-wash colour not above 2 is produced.

Ammonia Decomposition Catalyst Containing Ruthenium

nkk corp. World Appl. 8a/4,210A

An improved catalyst for decomposing NH, consists of a basic compound added to Ru supported on A12O3, or Ru carried on a basic compound carrier, where the basic compound can be an oxide or carbonate of an alkaline earth metal. The prepared catalyst is dried, and optionally baked at 400-600° C for 1-10h in air. The catalyst enables NH3 to be efficiently decomposed at temperatures as low as 500°C.

Iridium-Platinum-Halogen Naphtha Reforming Catalyst

exxon res. & eng. co. U.S. Patent 4,812,435

A naphtha reforming catalyst has 0.001-2 wt.% of an Ir component dispersed and bound to an A12O3 support by calcining, with 0.001-2 wt.% of a Pt component, then 0.001-2 wt.% of a halogen component dispersed on this. The catalyst is used for reforming naphthas to improve the octane number, and has high activity, gives a high C5+ liquid volume yield, is S tolerant, and can be regenerated without agglomeration of the Ir component.

Catalyst for Hydrocarbon Production from Synthesis Gas

exxon res. & eng. co. U.S. Patent 4,822,824

A catalyst consisting of Ru and Co supported on TiO2 is used in a process to form higher hydrocarbons by reacting H2 and CO at 190-260°C. The catalyst is prepared by impregnating TiO2 with Ru and Co salts, drying, reducing, forming oxides of Ru and Co, and reducing. Using the catalyst gives lower CH4 and higher C5+ yields than conventional Ru/Co or Co catalysts, and it can be regenerated in situ.

Improved Catalyst for Hydrocarbon Dehydrogenation

uop inc. U.S. Patent 4,827,072

Hydrocarbons are dehydrogenated on a composite catalyst having a Pt group metal with the concentration in the outer 100μm layer at least twice that in the centre; plus a Sn, Ge and/or Re modifier, and an alkali and/or alkaline earth metal component, all uniformly impregnated on an oxide support. The catalyst has improved stability, conversion and selectivity, giving products used in making detergents and plastics.

Platinum-Palladium Catalyst for Hydrogen Peroxide Manufacture

du font de nemours co. U.S. Patent 4,832,938

Hydrogen peroxide is manufactured by reacting H2 and O2 in an aqueous medium containing H+ and CI- or Br- ions, plus a catalyst containing Pt and Pd. The catalyst is prepared by mixing a preformed colloid containing Pt and Pd with a C, SiO2 or A12O2 support, to give a wt. ratio of Pt:Pt+Pd of 0.02-0.2:1. Use of this ratio leads to optimum reaction conditions.

Oxidation Catalyst for Hydrocarbon Fuels

tanaka kikinzoku kogyo Japanese Appl. 1/57,002

A combustor for hydrocarbon oxidation has a Pd-dominated catalyst on its former stage, and a Rh-dominated catalyst on its latter stage side with the Rh containing 0.1-10 wt.% Ce. The active components are dispersed on a support such as mullite coated with oxide(s) which are stabilised with other oxide(s). The usable life of the oxidising catalyst can be lengthened by preventing Rh deterioration at high temperature.

Durable Platinum-Palladium Catalyst for Catalytic Combustion

tanaka kikinzoku kogyo Japanese Appl. 1/58,346

Pd fine powders mixed with Ag, Cr, Mn, Fe, Co, Ni or Cu fine powders are thermally sprayed using the plasma spray technique to form a coating on a Pt support, which is then chemically etched with HQ. An oxidation catalyst with higher activity for catalytic combustion at 600-1500°C is prepared. There is good adhesion between the Pt support and Pd-based coating, so the catalyst is durable at high temperatures.

Palladium Catalyst for Preparation of Cycloolefins

shin-daikyowa sekiy Japanese Appl. 1/61,433

Cycloolefins are prepared more selectively by partial hydrogenation of cyclodienes at -20 to 120°C in the presence of a Pd-P or Pd-B catalyst. A thin film of the catalyst is prepared by sputtering Pd onto a base plate in the presence of P compounds or B compounds.

Rhodium on Stainless Steel Hydroformylation Catalyst

agency of ind. sci. tech. Japanese Appl. 1/63,040

A hydroformylation catalyst consists of stainless steel loaded with Rh, and is prepared by reacting stainless steel with Rh carbonyl in a hydrocarbon solvent, pressurised with synthesis gas. The catalyst is used for hydroformylation of an olefin by reaction with synthesis gas, while keeping the CO partial pressure <5 kg/cm2 and H2 partial pressure >100 kg/cm2.

Waste Gas Purification Catalyst

matsushita elec ind. k.k. Japanese Appl. 1/67,256

A catalyst used to remove CO, hydrocarbons or NO2 from waste gas consists of a porous ceramic support loaded with Pt, Pd, CeO2 or ZrO2. In an example a honeycomb structure was immersed in a solution having 1 g/1 Pd as PdCl3, 15 g/1 CeO2 as Ce(NO3)4 and 0.1 g/1 Pt as H2PtCl6, then fired at 1000°C. Using the catalyst NO2 can be removed efficiendy at a low temperature of 300-500°C.

Catalyst for Diesel Exhaust Denitrification

toyo kogyo k.k. Japanese Appl. 1/70,131

A catalyst system has a first catalyst with a carrier supporting one or more from alkali and alkaline earth metal(s), as well as Pt and Ni, where the Ni accelerates the Pt activity for the water-C reaction. The catalyst system is used for denitrifying diesel engine exhaust gas.

Exhaust Gas Purification Catalyst

toyota jidosha k.k. Japanese Appl. 1/70,146

A three-way catalyst consists of an activated A12O3 coated carrier, supporting a composite oxide of Ce oxide and Zr oxide, Rh adhered on the composite oxide or Ce oxide, and at least one of Pd or Pt on the oxides. The catalyst is used for removing CO, hydrocarbons and NOx from internal combustion engine exhaust gas, and prevents formation of a solid solution between A12O3 and Rh.

High Purity Trichlorosilane Production

nippon kokan k.k. Japanese Appl. 1/100,011

Trichlorosilane of high purity can be produced on an industrial level from tetrachlorosilane and H2 in the presence of a catalyst consisting of Pt group metal(s) and silicides of the metals on a support. Corrosion is prevented by using a special catalyst and at least two switching type regenerative ceramic reactors.

Exhaust Purification Catalyst

matsushita elec. ind. k.k. Japanese Appl. 1/104,344

A catalyst for removing CO, hydrocarbons or NO2 from exhaust gas consists of Pt, Pd and CeO2 on a moulded support containing A12O3 cement, fused SiO2, active A12O3 or hydraulic A12O3, and Li composite oxide. The support has high specific surface area and thermal resistance, and the interaction of the catalyst and the support leads to an increase in CO or NO2 purification ability.

Catalyst for Diesel Exhaust Purification

nippon shokubai kagaku Japanese Appl. 1/107,847

A diesel exhaust purification catalyst consists of a 3-dimensional heat resistant structure loaded with an inorganic oxide, having o. 1 -10 g of Pt, Pd or Rh and 1-60 g of Mn oxide in the surface layer, with a catalyst metal:Mn oxide molar ratio of 0.03-1.00. The catalyst has good durability, and is used to combust C particles in diesel engine exhausts at lower temperatures of 310-330°C.

Platinum Group Metal-MordeniteCatalyst for Various Uses

tosoh corp. Japanese Appl. 1/108,114

A multi-purpose catalyst consists of a Pt group metal supported on NH4-type mordenite containing hydrogen ions and 0.10-0.68 mol/kg NH4+ ions; the production involving sintering at 230-350°C. The catalyst is used for dewaxing, refining of H2, oxidising CO and hydrocarbons, and isomerisation of paraffins, giving higher product yields in the latter case.

New Palladium Catalyst for Methanol Synthesis

agency of ind. sci. tech. Japanese Appl. 1/123,633

A new catalyst used to produce CH 3 OH from H; and CO with higher efficiency and selectivity consists of synthetic mica loaded with Pd. In an example, a catalyst containing 3 wt.% Pd was used with a H2/CO mixed gas at 250°C and a total pressure of 30 atm.

Treatment of Hydrazine-Containing Waste Water

daido tokushoko k.k. Japanese Appl. 1/123,693

Treatment of N2H4 contained in high ion concentration in waste water involves adjusting the pH to 8.6-11.0 by adding alkali, contacting with a Pd catalyst and blowing air to oxidise the N2H4, and readjusting the pH to 7.2. The N2H4 in the waste is effectively decomposed using a smaller reactor.

Ruthenium Catalyst Preparation

mitsubishi kasei corp. Japanese Appl. 1/130,734

A Ru containing catalyst is produced by impregnating a support with a solution of nitrate anions and Ru optionally with other metals (preferably Co), adding alkali to the support to deposit Rh or other metals as hydroxides, removing the nitrate anions as water soluble salts, and drying and firing the solids.

Direct Production of Hydrogen Peroxide

mitsui toatsu chem. inc. Japanese Appl. 1/133,909

Hydrogen peroxide is produced by reaction of H2 and O, in aqueous solution in the presence of a catalyst consisting of a Pt group metal on a hydrophobic carrier such as porous Teflon. Hydrogen peroxide is produced in a one-step reaction, with better yield using this type of carrier. Also the accumulation concentration of the hydrogen peroxide is high, so the method is useful for industry.

Exhaust Gas Purification System

japan elec. control sys. Japanese Appl. 1/134,020

An internal combustion engine exhaust gas cleaning system consists of an O2 sensor able to control the air:fuel ratio via a feedback correction, and a ternary catalyst, such as a layer of activated A12O3 bearing Pt-Rh, and a reducing catalyst layer such as Rh on A12O3 upstream of the O2 sensor to accelerate NOx reduction. The system can suppress NOx emission during high-loading or high-speed running with high accuracy.

Oxidation Catalyst for Combustible Gases

mitsubishi heavy ind. k.k. Japanese Appl. 1/135,537

An oxidation catalyst consists of Pt, Pd, Rh, Ir, Os, Ru, Fe, Co or Ni oxides or other metallic oxides on a double oxide support with an Al:alkaline earth metal: rare earth metal atomic ratio of 100:0.5-100:0.5-100. The catalyst is used to combust and remove CO, H2 or hydrocarbons from car exhaust at lower temperatures, and also has improved heat resistance, providing higher activity at 300-1500°C over a long period.

Waste Gas Purification Catalyst

toyota jidosha k.k. Japanese Appl. 1/135,538

A catalyst used to remove CO, NOx and hydrocarbons from combustion exhaust is prepared by loading Pt and Rh on an activated A12O3 coated support from an aqueous solution of Pt(NH3)2(NO3)2, Rh(NO3)2 and (NH3)3Rh(NO3)6 containing 0.05-5 g/1 Pt+Rh. The catalyst has improved high temperature durability, and growth of the precious metal particles and penetration into the A1203 coating is prevented by using a Pt-Rh solid solution catalyst.

Higher Efficiency NOx Removal Catalysts Containing Zeolite

toyota jidosha k.k Japanese Appls. 1/135,540-41

Waste gas purification catalysts are prepared by (a) loading a slurry of zeolite, silica sol, alumina sol and water on a monolithic support, firing, and exchanging the zeolite ions with Pt, Pd, Rh, Ir, Ru, Ce, Ni, or others, or (b) ion-exchanging the original ions of a zeolite with Pt, Pd, Rh, Ir or Ru, The catalysts have higher efficiency for NOx removal from car exhaust under O2-rich or fuel-lean conditions. NOx is selectively adsorbed in the micropores of the zeolite.

Palladium Catalyst for Catalytic Combustion System

mitsubishi heavy ind. k.k. Japanese Appl. 1/139,911

In a catalytic combustion system for combustible gases such as CO, H2 or hydrocarbons the gas is contacted with a honeycomb or pelletised 0.01-10 wt.% Pd catalyst at 300-800°C, and then with a catalyst containing an alkaline earth metal and an Al-Mn compound oxide at 600-1300°C. The system can burn the gases completely and stably even at high temperatures, for long periods.

Benzene Hydrogenation Catalyst

as. ussr kola rare m. Russian Patent 674,292

A benzene hydrogenation catalyst is prepared by impregnation of Al2O3 with an aqueous solution of a Pt compound, for drying and heat stabilising, which to increase performance is K chloroplatinite at 10-160 mg of Pt/1. The simplified process increases catalyst activity; the benzene transformation rate is 95% on heat stabilisation under H2 at 150°C for 1 h.


ruthenium catalyst system for ketone production shell int. res. mij. b.v. British Appl. 2,208,480A

A catalyst system consisting of a Ru compound and acid(s) from a halogen acid or a carboxylic acid of pKa not more than 3 is used in the preparation of ketones. The reaction involves carbonylation of alkenes with CO in the presence of an H2 source, at 70-200°C and 20-100 bar in an H2O-miscible solvent, and produces ketones at improved conversion rates and selectivity.

Catalyst for Oxidising Organochlorine Compounds

univ. of sydney World Appl. 89/5,172A

Organochlorine compounds which are CI- but not OH-substituted ring structures can be oxidised at room temperature by a Ru or Os compound in the presence of a base and an oxidising agent able to form the catalytic metal tetroxide. The process is for degrading or transforming organochlorides in industrial waste products, and is an alternative to high-temperature combustion.

Palladium-Copper Catalyst for Alkyl Acrylate Production

texaco inc. U.S. Patent 4,814,492

Producing an alkyl acrylate continuously involves reacting ethylene with CO, O2 and a 1-5C alkanol in the presence of a PdCl2/CuCl2 catalyst to form a 1-5C alkyl methoxy propionate with high selectivity, then contacting this with a base-treated zeolite catalyst to give a 1-5C alkyl acrylate. The process runs readily at low pressure, and is especially used for producing methyl acrylate used for surface coatings.

Rhodium Hydroformylation Catalyst

kuraray k.k. Japanese Appl. 1/40,434

Hydroformylation of vinyl compounds is achieved by treating with synthesis gas in the presence of Rh compound(s), tris(substituted phenyl)phosphite(s), and a bidentate ligand, using 0.005-0.1 mg.atom. Rh/1 of catalyst. The product is used in food additives, synthetic resins, and so on, and is obtained efficiently in high yield, using a smaller amount of Rh compounds than in prior arts.

Production of Methylanilines from Aminophenyl Compounds

daicel chem. ind. k.k. Japanese Appls. 1/45,345-46

Methylanilines are produced from aminophenyl compounds by (a) reductive decomposition with formic acid, or (b) hydrogenolysis with H2; in the presence of a catalyst containing at least one of Pt, Pd, Rh, Ir, Os and Ru, optionally supported, in an amount of 0.0001-0.5 mol/mol of aminophenyl compound. Reaction is at 10-100°C and gives a good yield of methylanilines under mild conditions; useful in the preparation of drugs and agrochemicals.

Hydrogen Production by Light Irradiation of a Hydrocarbon

agency of ind. sci. tech. Japanese Appl. 1/126,201

H2 is manufactured by irradiation of a hydrocarbon with a mercury lamp in the presence of a Rh complex of an organic phosphorus compound such as phosphine, or in the co-presence of the organic phosphorus compound and a Rh compound. H2 is produced by dehydrogenation of a hydrocarbon without using thermal decomposition.

Palladium Catalyst for Methanol Oxidation

m. n. vargaftik Russian Patent 1,426,631

A proposed catalyst for methanol oxidation consists of 62-90 wt.% Pd and balance 1,10-phenanthroline, and is prepared by adding the latter to a Pd base at molar ratio 15-3:1, followed by dissolution in methanol and treatment with H,. The catalyst shows increased activity and selectivity for oxidation of methanol to methyl formate, which is used as an intermediate for synthesis of formic acid and dimethyl formamide.


Platinum-Gallium Fuel Cell Electrocatalyst

engelhard minerals corp. U.S. Patent 4,822,699

An improved electrocatalyst consists of a Pt-Ga alloy with 5-50 at.% Ga and surface area of at least 30 m2/g, dispersed on a conductive C carrier to give 0.1-30 wt.% alloy. The alloy is used at 0.1-2 mg/cm2 on a support as an O2; reduction cathode for an acid fuel cell. A fuel cell electrocatalyst with good retention of surface area in use is provided.

Improved Electrode Catalyst for a Fuel Battery

fuji electric mfg. k.k. Japanese Appl. 1/41,170

An electrode catalyst is made from a catalyst having Pt microparacles supported on C black by dispersing in water, mixing and dissolving an oxyacid salt of Ti or W, adding acid to precipitate the oxyacid of the Ti or W on the Pt catalyst, and then burning in a reducing atmosphere. Using this method the Ti or W is readily alloyed and an electrode catalyst for a fuel battery can be obtained, having improved activity and durability.

Platinum-Nickel Alloy Fuel Cell Catalyst

tanaka kikinzoku kogyo Japanese Appl. 1/45,061

Preparation of a catalyst consisting of a Pt-Ni alloy supported by electroconductive C involves heat treating the C black, reducing Pt from solution to obtain Pt-C, adding the Ni, and then heat treating in a N2/5% H2 atmosphere at 920°C. The catalyst is used for a fuel cell electrode, and suppresses coagulation of the fine Pt particles which decreases the Pt surface area while the electrode is used.


Supported Pore-Free Palladium-Based Membrane

t. allmendinger World Appl. 89/4,556A

A pore-free Pd-based membrane is made by electrodeposition of Pd or Pd-Ag alloy onto or into a porous metal body. The membrane can be used for selective separation or purification of H2 gas, or as a H2-permeable electrode in a fuel cell or electrolysis cell, the Pd/Ag side having a Pd or Pt black catalyst. The membrane can be produced less expensively and more efficiently, directly on a porous metal body.

Biological Recovery of Platinum from Waste Water

oak ridge res. inst. U.S. Patent 4,826,602

Heavy metal species such as Pt2+, Au+, Ag+, Pb2+, Cu2+ and SeO32- in aqueous waste liquors from mining for example, are converted to the metals by contact with a pseudomonas maltophila ATCC 53510 culture, at 5-35°C, pH 6-8, under aerobic conditions and in the presence of a nutrient medium. At least one elemental metal is recovered after filtering, reducing the ionic species in the waste water, and giving a treated effluent suitable for recycling.

Extraction of Iridium from Furnace Linings

gorki univ. Russian Patent 1,428,703

Metallic Ir deposited on ZrO2 ceramic furnace linings on evaporation from crucibles is removed by fusing with NaOH at 500-600°C, cooling, washing, treating with concentrated HCl, washing and separating the Ir in the form of compact flakes. The method allows extraction of Ir as metal instead of a salt solution as before, and the ceramic can be re-used.


Integral Tube-Stirrer Assembly with Platinum-Rhodium Alloy Blade

owens-illinois tele. U.S. Patent 4,832,725

A rotating tubular stirrer element for use in a glass feeder has a stirrer consisting of an elongated suspended hollow blade of Pt-Rh alloy with parallelogram cross-section. The apparatus combines tube and stirrer into one rotating assembly, so only a single drive is needed. Discharged glass of improved quality is supplied for production of pressed optical glass parts, especially television tube faceplates.

Shaping Die for Shaped Glass Product Manufacture

hoya corp. Japanese Appl. 1/72,932

A shaping die for use in press-shaping of glass consists of a base with a surface layer of 10-90 wt.% Pt, 5-40 wt.% Ni and/or Cr and 5-70 wt.% SiC, optionally with Pd, Rh, Ir, Au or their mixtures which may be further incorporated in the surface layer composition. The join between the base and the surface layer is good, and using the die, detachability of the shaped product is good.

Platinum-Cobalt-Carbide Layer for Glass Shaping Die

tanaka kikinzoku kogyo Japanese Appl. 1/111,740

A glass shaping die has a base and a surface layer consisting of Pt as the major component with 5-45 wt.% Co, and 0.02-30 vol.% of carbide(s) dispersed in the layer, preferably TiC, TaC, B.C, SiC, HfC, ZrC or VC. Face accuracy is kept in excellent state by suppressing crystal growth.


Oxidation Resistant Magneto-Optical Recording Medium

mitsui petrochem. ind. k.k. European Appl. 320,286A

The medium has a transparent substrate, a first protective film, a magneto-optical recording film, and a second protective film. The recording film contains Pt and/or Pd, at least one of Pt, Nd, Sm, Ce or others, and Fe and/or Co, and has an easy axis of magnetisation perpendicular to the face.

Noble Metal Coating for Thin Film Circuit

mitsui mining & smelting World Appl. 89/6,086A

A new Ta thin film conductive circuit is formed on an insulator or semiconductor substrate via a Ta oxide adhesion layer, and the surface of the circuit is partially or wholly covered with at least one of Pt, Pd, Rh, Au, or an alloy of these. The products are useful as circuits with good resistance to electrical corrosion.

Long Life Cathode Containing Barium Iridate

u.s. sec. of the army U.S. Patent Appl. 7,252,945

A long life, high current density cathode is prepared by milling and pressing a mixture of 65 wt.% W, 34 wt.% Ir and 1 wt.% ZrO2 activator into a billet, sintering in dry H2, treating to make porous, and then impregnating with Balr03, Ba2Ir04 or Ba4,IrO6 , formed from BaO2 and IrO2 in a molar ratio of 1:1, 2:1 or 4:1, respectively. The method is rapid and requires relatively low temperatures.

Composite Electrode for Remote Power Applications

calif. inst. of techn. U.S. Patent 4,820,596

A composite electrode consists of a monocrystalline A12O3 ceramic electrolyte, and a porous electrode film of a Pt group metal and a Group IV-VIB metal on one surface, which is non-volatile at 1300K. The electrode is for alkali metal thermoelectric converter (AMTEC) devices having fast Na transport and low electronic resistance. It has high efficiency, is simple, durable, needs little maintenance, and the AMTEC is used for remote power applications.

Platinum Film for Thin Film Oxide Superconductor

matsushita elec ind. k.k. Japanese Appl. 1/6,322

A thin film oxide superconductor consists of a substrate supporting a superconducting perovskite oxide thin film oriented vertically, then a Pt thin film, and another superconducting thin film of MBa2Cu3O7-y where M is Y, Lu, Sc or others. The superconductor is used for a proximity effect type Josephson device, having Tc near that of ceramics on an electrically conductive substrate.

Random Texture Magnetic Recording Medium

asahi glass k.k. Japanese Appl. 1/37,722

A process for producing a magnetic recording medium involves sputtering Co-Pt magnetic alloy on a glass substrate having randomly-set point-form protrusions on the surface, in an in-line type continuous sputtering device. The random texture is effective for lowering the fraction coefficient, and facilitating magnetic head floating.

Information Recording Medium with Platinum-Manganese-Antimony Alloy

toshiba k.k. Japanese Appl. 1/62,843

An information recording medium consists of a substrate and a magnetic layer formed with an alloy of Pt, Mn, Sb, and at least one of Nd, Pr, Sm, Co, Fe, Ni, and others. The alloy is present in the direction of easy magnetisation, vertical to the surface. Information is recorded and erased by causing magnetic inversion in the magnetic layer by heat from light beam irradiation, and reproduced by irradiating light beams on the layer.

Production of Composite Silver-Palladium Fine Particles

tanaka kikinzoku kogyo Japanese Appls. 1/75,601-03

Composite Ag-Pd type fine particles are produced by (a) depositing Pd evenly on the surface of fine Ag particles, (b) depositing Ag evenly on the surface of fine Pd particles, or (c) depositing Ag and Pd at the same time, achieved in each case by H2 or chemical reduction from solution, and followed by heat treatment to form an alloy in case (c). The composite Ag-Pd type fine particles can be evenly dispersed into a conductive paste material, for use in the manufacture of circuit substrates.

Platinum-Manganese-Antimony Photo-Electromagnetic Recording Medium

riken corp. Japanese Appl. 1/76,550

A photo-electromagnetic recording medium is a thin membrane of an intermetallic compound of Pt-Mn-Sb. The medium has perpendicular magnetic anisotropy, and a big coercive force in the vertical direction of more than 300 Oe, as well as a big force-rotation angle.

Coating Layer for Superconductive Complex Material

fujitsu ltd. Japanese Appl. 1/76,610

A superconductive complex material consists of a superconductor containing O2, coated with a layer which O2 and water cannot penetrate. The coating layer may consist of Pt, Pd, Rh, Ir, Os, Ru, Au, Ag, Cu or their alloys, certain other metals, or dielectrics. Optimum composition for the superconductive superconductor can be maintained, and the material is used for magnet circuits, and SQUID magnetic flux meters.

Palladium Metallising Paste for Low Thermal Expansion Board

ngk spark plug k.k. Japanese Appl. 1/76,988

A metallising paste consists of 100 parts wt. Pd powder, 1-10 parts wt. low expansion frit, 0.5-4 parts wt. Ag powder, 0.1-1 parts wt. CuO, and preferably up to 50 parts wt. Au as a sintering aid. The paste is used for IC mounting multi-layer boards using low thermal expansion coefficient material, giving sufficient bonding strength even if high-temperature brazing material such as pure Al is used.

Composition for Electric Conductive Film

sumitomo metal mini. k.k. Japanese Appl. 1/81,866

A composition for forming an electric conductive film has an organic vehicle and a composite filler consisting of 0.03-0.5 wt.% Pd powder, 1-10 wt.% glass powder with softening point 400-700°C, and balance Cu powder. The composition gives a coating film with improved adhesion, mechanical strength, and solder-wetting property. It is useful for preparing patterned electric circuits or electrodes on ceramic substrates.

Electrical Recording Head

canon k.k. Japanese Appls. 1/87,271-72

An electric current recording head consists of a substrate with an optional adhesive layer and a Pt group metal electrode pattern obtained by electroless plating, which is electrochemically stable and has improved adhesion to the substrate. The electrode is of Pt, Pd, Rh, Ir and/or Ru, especially Pt or Pt alloy, and is o.1-3μm thick. The recording head has a fine electrode pattern obtained for less cost.

Alternatively Laminated Multilayer Reflecting Mirror

canon k.k. Japanese Appls. 1/94,299-300

A multilayer film reflecting mirror for X-rays and vacuum UV rays has a surface with alternate laminated layers of materials of different refractive indexes, with at least one layer of the film being crystalline. The layers may consist of (a) Ru and Si of low and high refractive index respectively, with a final graphite layer, or (b) one or more Pt group metals and Be, B, C and Si. The mirror is used for radiation of <200 nm wavelength, has higher reflectivity, and good resistance to long term irradiation.

Recording Layers for Photomagnetic Recording Media

sony corp. Japanese Appls. 1/98,143-44

Photomagnetic recording media have recording layers of super-lattice metal thin film obtained by alternately laminating either (a) 0.5-1.5 atom layers of a Co alloy and 1 -7 atom layers of Pd, or (b) a Ni layer having 3-8 atom layers and a Pt layer of 1/2-2 atom layers. A medium is produced which (a) has excellent thermal stability, or (b) is capable of recording, reproducing information by laser light, and maintaining magneto-optical effects stably while corrosion is limited.

Composition for Insulation Covering of Electric Wires

fujikura cable works k.k. Japanese Appl. 1/108,258

A flame-retardant silicone rubber compositon for the insulation covering of electric wires consists of 100 parts wt. silicone rubber, 0.002-0.03 parts wt. Pt type flame retardant—for example Pt(II) chloride, 0.01-10 parts wt. metal oxide, and 0.1-30 parts wt. silane coupling agent. Toxicity is <1.5 with less generation of formaldehyde, and the oxygen index, electric insulation and tangent delta properties are good.

Composite Magnetic Heads

sony corp. Japanese Appl. 1/113,906

In magnetic heads consisting of a pair of magnetic half cores, at least one of which consists of an oxide magnetic material, and metallic magnetic film, the composite magnetic head is prepared by adding O and at least one of Pt, Pd, Rh, Ir, Os, Ru, Sc, Zr and Mo. Metallic films composed of Ru, Fe, Si, Al or Ga, and containing O, are preferably used.

Fine Palladium Powder for Electroconductive Paste

sumitomo metal mini k.k. Japanese Appl. 1/136,911

A spherical-grained fine Pd powder used for electroconductive pastes is manufactured by dissolving Pd chlorides and/or Pd chloro-complexes to give an aqueous solution containing 10-60 g/1 Pd, controlling the solution pH to 7-11, and adding reducing agent while maintaining the temperature at 10-50°C.

Magnetic Polycrystal for Use at Low Temperatures

toshiba k.k. Japanese Appl. 01/140,701

A magnetic polycrystal is formed by high pressure pressing of magnetic alloy microcrystals with a 10-40 vol.% surface coating layer of at least one of Pt, Pd, Rh, Ni and Th. The coating layer has a density of at least 8 g/cm3, and a face-centred cubic lattice structure. The polycrystal is used below the temperature of liquid N2, and has a good magnetic heat quantity effect, and conductivity in a wide temperature range at low temperature.

Thin Film Magnetic Head

hitachi k.k. German Appl. 3,833,901

A thin film magnetic head useful as a read/write head in a computer magnetic disc unit has a pair of magnetic cores, at least one of which is a thin film of Co alloy of composition 5-32 at.% Pd, 20-70 at.% Co, 20-60 at.% Ni and 12-30 at.% Fe. The core has improved resistance to heat produced in manufacture of the head, and has magnetic properties corresponding to those of plated ternary Co-Ni-Fe films.


High Resistance Platinum Temperature Sensors

murata mfg. co. German Appls. 3,829,764-65

A Pt temperature sensor consists of (a) a cylindrically coiled, plate-shaped ceramic film with a Pt resistance pattern on the inner or outer surface, or (b) a number of sintered, stacked ceramic plates, each carrying a Pt resistance pattern on a surface, and each pattern having curved regions. The patterns are connected via through holes and resistance adjustment wires.

Platinum Thermometric Sensitive Elements

r.a. pristaiko Russian Patent 1,427,190

Thermometric sensitive elements are made by sealing a Pt winding in the channel of a ceramic body using a powder of Al oxide and potassium phosphate, then heating and cooling. The winding is a cylindrical spring of Pt wire of diameter 0.02-0.1 mm, and the wire is soldered to terminals of Pt or Pt-Rh wire of diameter 0.3-0.5 mm. The elements are used in the manufacture of Pt resistance thermoconverters.


Platinum Complexes Useful as Anti-Tumour Agents and Chiral Catalysts

s. hanessian British Appl. 2,210,039A

New 3,4-diarnino tetrahydropyran Pt(II) complexes are useful as anti-microbial and anti-tumour agents, and as chiral catalysts and intermediates for catalysts for asymmetric synthesis. The compounds have a screening profile similar to cisplatin, but are more soluble in physiological saline, and may be active against cisplatin-resistant tumours. Doses used are for example 5-200 mg/kg/day.

New Platinum Anti-Tumour Agents

bristol-myers co. European Appl. 3l8,464A

New Pt(II) complexes useful as anti-tumour agents include 1,2-diaminocyclohexane Pt(II) complexes, and phosphonoacetato - 1 - aminomethylcyclooctylamine Pt(II). Preparation is from a dichloro Pt(II) complex by reaction with the Ag salt of the ligand, or by converting to the dinitrato complex and reacting with an alkali metal salt of the ligand, or by converting to the dihydroxy complex and reacting with the ligand.

Platinum Anti-Tumour Drug with Improved Resolubility

nippon kayaku k.k. European Appl. 318,906A

A lyophilised composition consists of dextran and a cyclobutane dicarboxylate methylbutanediamine Pt(II) complex. The Pt compound is useful as an anti-tumour drug, but is relatively unstable in aqueous solutions, so is used in lyophilised form, and with the use of dextran a composition of greatly improved resolubility is obtained.

Immobilised Enzyme Electrode Containing Platinum Particles

cambridge lipe sci. World Appl. 89/3,871A

An enzyme electrode consists of a resin-bonded porous surface layer of C or graphite particles oxidised to form an oxide layer, with finely divided Pt oxide or Pt metal, and an immobilised or adsorbed enzyme on the surface. The electrode uses oxidoreductases such as glucose oxidase for the detection and/or quantitation of glucose, and allows reliable determination in samples containing alcohol, to which prior electrodes were sensitive.

Apparatus to Manoeuvre a Radioactive Implant

s.f. liprie U.S. Patent 4,819,618

A radioactive implant is manoeuvered through a human body using an apparatus which includes a guide, the implant and a wire secured to it, where the implant consists of a core of radioactive Ir encased in a Pt sheath. The radioactive implant can be used to treat tumours, can be cut to any desired length, and can be implanted in the correct position even in troublesome areas of the body, without kinking along its length.

Platinum Complex for Anti-Tumour Agents

agency of ind. sci. tech. Japanese Appl. 1/125,325

Anti-tumour agents contain a Pt green complex having 3-18 Pt atoms and for example uridine, thymidine, uracil, or thymine co-ordinated with cis-diacodiammine Pt(II). The complex is prepared by reaction in a solvent, for 30 minutes to 2 months, at pH 2-8, and 0-100°C. The agent is active against Li 210, and may be administered orally or parenterally at single or divided doses, particularly 1-500 mg/kg/day.

Yellow Dental Casting Alloy

toyo kagaku kenkyus Japanese Appl. 1/129,939

A yellow colour dental casting alloy consists of 1-5% B-Cu alloy, 5-15% Pd, 2-35% Au, 20-50% Ag, 10-26% In, and 1-5% Zn. The B-Cu alloy exerts the same effect as Cu for improving mechanical strength, castability, and operability of the alloy, and prevents formation of an oxide film.

Gold Base Alloy for Artificial Teeth

ishifuku zinzoku ko. Japanese Appl. 1/132,728

A Au base alloy which is gold in colour consists of 75-98 wt.% Au, 0.1-15 wt. Pt, 0.1-10 wt.% Fe, 0.1-3 wt.% In and 0.05-5 wt.% W, and optionally contains at least one of 0. 1-3 wt.% Pd, Ag, Sn or Cu, or 0.05-1 wt.% Rh or Ir. The alloy is used for making artificial Au alloy teeth coated with ceramic materials. The mechanical properties, adhesion, castability, and reappearance of colour tone of natural teeth are improved.

Corrosion Resistant Precious Metal Dental Alloy

comp. lyon-alemand French Appl. 2,620,133

A novel Au-Ag-Pd alloy has the composition 5-20 wt.% Pt, 20-50 wt.% Pd, 15-50 wt.% Au, 20-50 wt.% Ag, 2-10 wt.% In, and 0-2 wt.% of one or more of Rh, Ir and Ru (preferably Ru). The alloy is used for the preparation of dental prostheses, especially of the ceramic/metallic type. Addition of Au and Pt to Ag-Pd dental alloys imparts a corrosion resistance equivalent to that of very high Au content alloys.

Improved Artificial Eye Lens

mosc. eye microsurge. Russian Patent 1,428,368

High quality artificial crystalline eye lens contains a mixture of methyl-phenyl siloxane derivatives vulcanised over a Pt catalyst, such as H2PtCl6.4H2O. The mechanical and optical properties of the lens are increased by 10 and 1.3 times, and the lens can be used for correction of vision after cataract removal, reducing post-operational treatment from 3 to 1 month, and time in bed from 7 to 3-4 days.

The New Patents abstracts have been prepared from material published by Derwent Publications Limited.