An electroplating apparatus includes a plating bath and a substrate in a horizontal direction. The electroplating apparatus further includes a plurality of cathodes on first and second sides of the substrate in a first direction on one surface of the substrate, and an anode above the substrate, the anode being spaced apart from the substrate and configured to be movable in the first direction.

A plating device comprising: a water tank into which a plating solution is poured; a tubular nozzle being disposed in the water tank and serving as an anode; a to-be-plated object being disposed in the water tank so as to be opposed to the nozzle and serving as a cathode; a direct-current power source to apply a voltage between the nozzle and the to-be-plated object; and a pump to circulate the plating solution such that the plating solution poured into the water tank passes through the nozzle and is ejected onto the to-be-plated object. A perforated plate member, which includes a through-hole having a smaller diameter than the inside diameter of the nozzle, is arranged on the inflow side of the nozzle such that the through-hole is opposed to an open region of the nozzle.

A plating device comprising: a water tank into which a plating solution is poured; a tubular nozzle being disposed in the water tank and serving as an anode; a to-be-plated object being disposed in the water tank so as to be opposed to the nozzle and serving as a cathode; a direct-current power source to apply a voltage between the nozzle and the to-be-plated object; and a pump to circulate the plating solution such that the plating solution poured into the water tank passes through the nozzle and is ejected onto the to-be-plated object. A perforated plate member, which includes a through-hole having a smaller diameter than the inside diameter of the nozzle, is arranged on the inflow side of the nozzle such that the through-hole is opposed to an open region of the nozzle.

A treatment device has: a treatment tank provided with a constant temperature heater on the outer periphery; an electrolytic cell continuing from a pipe provided with a circulation pump; and a pipe for supply to the treatment tank from the electrolytic cell. Within the electrolytic cell are provided an anode and a cathode formed from diamond electrodes and a bipolar electrode disposed between the two. The treatment tank and the electrolytic cell are filled with a prescribed concentration of sulfuric acid. The treatment device is configured such that a persulfate solution such as peroxydisulfuric acid is generated by electrolysis of the sulfuric acid by making a prescribed current flow from a direct current power supply unit to the anode and the cathode, and this persulfate solution can be supplied to the treatment tank via the pipe.

A treatment device has: a treatment tank provided with a constant temperature heater on the outer periphery; an electrolytic cell continuing from a pipe provided with a circulation pump; and a pipe for supply to the treatment tank from the electrolytic cell. Within the electrolytic cell are provided an anode and a cathode formed from diamond electrodes and a bipolar electrode disposed between the two. The treatment tank and the electrolytic cell are filled with a prescribed concentration of sulfuric acid. The treatment device is configured such that a persulfate solution such as peroxydisulfuric acid is generated by electrolysis of the sulfuric acid by making a prescribed current flow from a direct current power supply unit to the anode and the cathode, and this persulfate solution can be supplied to the treatment tank via the pipe.

A method for the production of a metal strip coated with a coating. The coating containing chromium metal and chromium oxide and is electrolytically deposited from an electrolyte solution that contains a trivalent chromium compound onto the metal strip by bringing the metal strip, which is connected as the cathode, into contact with the electrolyte solution. An effective deposition of the coating with a high chromium oxide portion is achieved by successively passing the metal strip at a predefined strip travel speed through a plurality of electrolysis tanks arranged successively in a strip travel direction. The first electrolysis tank is set to a low current density; a second electrolysis tank, which follows in the strip travel direction, is set to a medium current density; and a last electrolysis tank is set to a high current density, where the low current density is greater than 20 A/dm.sup.2.

A method for the production of a metal strip coated with a coating. The coating containing chromium metal and chromium oxide and is electrolytically deposited from an electrolyte solution that contains a trivalent chromium compound onto the metal strip by bringing the metal strip, which is connected as the cathode, into contact with the electrolyte solution. An effective deposition of the coating with a high chromium oxide portion is achieved by successively passing the metal strip at a predefined strip travel speed through a plurality of electrolysis tanks arranged successively in a strip travel direction. The first electrolysis tank is set to a low current density; a second electrolysis tank, which follows in the strip travel direction, is set to a medium current density; and a last electrolysis tank is set to a high current density, where the low current density is greater than 20 A/dm.sup.2.

Disclosed are novel electrolytes, and techniques for making and devices using such electrolytes, which are based on compressed gas solvents. Unlike conventional electrolytes, disclosed electrolytes are based on compressed gas solvents mixed with various salts, referred to as compressed gas electrolytes. Various embodiments of a compressed gas solvent includes a material that is in a gas phase and has a vapor pressure above an atmospheric pressure at a room temperature. The disclosed compressed gas electrolytes can have wide electrochemical potential windows, high conductivity, low temperature capability and/or high pressure solvent properties. Examples of a class of compressed gases that can be used as solvent for electrolytes include hydrofluorocarbons, in particular fluoromethane, difluoromethane, tetrafluoroethane, pentafluoroethane. Also disclosed are battery and supercapacitor structures that use compressed gas solvent-based electrolytes, techniques for constructing such energy storage devices. Techniques for electroplating difficult-to-deposit materials using compressed gas electrolytes as an electroplating bath are also disclosed.

Disclosed are novel electrolytes, and techniques for making and devices using such electrolytes, which are based on compressed gas solvents. Unlike conventional electrolytes, disclosed electrolytes are based on compressed gas solvents mixed with various salts, referred to as compressed gas electrolytes. Various embodiments of a compressed gas solvent includes a material that is in a gas phase and has a vapor pressure above an atmospheric pressure at a room temperature. The disclosed compressed gas electrolytes can have wide electrochemical potential windows, high conductivity, low temperature capability and/or high pressure solvent properties. Examples of a class of compressed gases that can be used as solvent for electrolytes include hydrofluorocarbons, in particular fluoromethane, difluoromethane, tetrafluoroethane, pentafluoroethane. Also disclosed are battery and supercapacitor structures that use compressed gas solvent-based electrolytes, techniques for constructing such energy storage devices. Techniques for electroplating difficult-to-deposit materials using compressed gas electrolytes as an electroplating bath are also disclosed.

Soluble copper oxide powder capable of preventing a decrease in quality of a copper film formed by plating is disclosed. The copper oxide powder contains copper and impurities including sodium. A concentration of the sodium is not more than 20 ppm. The copper oxide powder is regularly supplied into a plating solution. A voltage is applied between an insoluble anode and a substrate immersed in the plating solution, thereby plating the substrate.