Tdk Corporation

Tdk Electronics Company, Limited

Toyo Ink Mfg. Co., Ltd.

Yukio Kawashima

Kazuhide Ohe

Hiroyuki Nakada

Makoto Kobayashi

Makoto Kondo

Masumi Koishi

Hiroaki Saito

Mayu Murakami

Masuyuki Takada

Akio Kazama

An electrolyzing electrode which is for electrolyzing a metal electrolytic solution, shows a long lifetime in use as an ordinary anode and has sufficient durability even when in a poor potential region, and a process for the production thereof. The electrolyzing electrode of the present invention has an undercoating layer which is formed of platinum metal and tantalum oxide and contains, as metals, 1 to 20 at % of platinum and 80 to 99 at % of tantalum, on an electrically conductive electrode substrate, has an intermediate layer which is formed of iridium oxide and tantalum oxide and contains, as metals, 70 to 99.9 at % of iridium and 0.1 to 30 at % of tantalum, on the undercoating layer, and further has an overcoating layer which is formed of platinum metal and iridium oxide and contains, as metals, 60 to 99.9 at % of platinum and 0.1 to 40 at % of iridium, on the intermediate layer.

Electrolyzing electrode and process for the production thereof

A length of electroplated metal foil, typically copper foil is prepared by placing a stationary arcuate anode concentrically with a rotating cathode drum to define a channel therebetween, passing a plating solution through the channel, conducting electricity across the channel for depositing metal on the cathode drum, and separating the metal deposit from the cathode drum. The anode includes a plurality of circumferentially arranged electrode segments formed of a valve metal material and coated with a platinum group metal or oxide thereof. The electrode segments are removably attached and electrically connected to a back plate. The split anode is easy in assembly and disassembly and, hence, in maintenance and repair, has a high degree of precision in configuration and dimensions, and ensures manufacture of copper foil of quality with a minimized variation in thickness during continuous operation.

Electroplating method and apparatus for the preparation of metal foil

An oxygen generating electrode has on a conductive substrate a first layer of metallic platinum and tantalum oxide containing 80-99 mol% of Ta and 20-1 mol% of Pt, a second layer of iridium oxide and tantalum oxide containing 80-99.9 mol% of Ir and 20-0.1 mol% of Ta, and preferably a third layer of iridium oxide and tantalum oxide containing 40-79.9 mol% of Ir and 60-20.1 mol% of Ta. In another embodiment, the first layer consists of iridium oxide and tantalum oxide and contains 14-8.4 mol% of Ir and 86-91.6 mol% of Ta. The electrode, when used as an anode in electrolysis with concomitant oxygen generation, can be used for an extended period at a low bath voltage. It is adapted for electrolysis at a high current density of more than 100 A/cm.sup.2 since it maintains mechanical strength and has a long effective life. It experiences a minimal change of oxygen overvoltage with time.

Oxygen generating electrode

The electrode of the invention suitable for use in an oxygen-generating electrolytic process with durability comprises (A) a substrate of, e.g., titanium metal; (B) an undercoating layer thereon which is formed of a mixture of an iridium oxide and tantalum oxide in a limited molar proportion and (C) an overcoating layer formed of an iridium oxide. The undercoating layer can be formed by coating the substrate surface with a solution containing an iridium compound and tantalum compound each having thermal decomposability and then subjecting the coated substrate body to a heat treatment in an oxidizing atmosphere. Similarly, the overcoating layer can be formed by coating with a solution containing a thermally decomposable iridium compound followed by an oxidative heat treatment in an oxidizing atmosphere.

Oxygen-generating electrode and method for the preparation thereof

Proposal is made for providing a high-performance electrode suitable for use in an oxygen-generating electrolytic process having an outstandingly low oxygen overvoltage and exhibiting high durability in a prolonged run of electrolysis. The electrode consists of an electroconductive substrate of a metal, e.g., titanium, and a multiple composite oxide coating layer thereon consisting of at least one layer of type A composed of iridium oxide and tantalum oxide in an Ir:Ta molar ratio of 40:60 to 79.9:20.1 and at least one layer of type B formed on the type A layer composed of iridium oxide and tantalum oxide in an Ir:Ta molar ratio of 80:20 to 99.9:0.1. A plural number of type A layers and a plural number of type B layers can be alternately laid one on the other so as to improve the mechanical stability of the coating layer on the substrate surface.

Oxygen-generating electrode

A toner for use in electrophotography comprising thermoplastic resin core particles (A) or colorant-embedded thermoplastic resin core particles (A') each having an average particale size of 1 to 15 .mu.m, a charge-controlling agent (B) and carrier particles (C) having an average particle size of 0.05 to 2.0 .mu.m, the charge-controlling agnet (B) being carried on the carrier particles (C), and the carrier particles (C) with the agent (B) carried thereon being embedded in the surfaces of the resin core particles (A) or the colorant-embedded resin core particles (A').

Toner for electrophotography with the change controlling agent dispersed

An anode comprising an electroconductive substrate provided with a (Ru-Sn)O.sub.2 solid solution coating is useful in brine electrolysis. The improved coating has a composition of (i) 3 to 45 mol % of ruthenium oxide, (ii) 0.1 to 30 mol % of at least one member selected from metallic platinum, platinum oxide, and iridium oxide, and (iii) 50 to 96.9 mol % of tin oxide which may be partially replaced by antimony.

Electrode for electrolysis

An electrode for electrolysis having a coating which consists esentially of 40 to 90 mole % of palladium oxide, 0.1 to 20 mole % of platinum, and 5 to 50 mole % of (Ru.sub.x Ti.sub.1-x)O.sub.2 wherein x ranges from 0.05 to 0.5, based on the total molar composition. The electrode of the present invention has excellent corrosion resistance and mechanical resistance against foams generated during electrocatalysis.

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Tokyo, Japan

Yukio Kawashima