An electrochemical probe comprises a wire bundle including two or more wire electrodes made of conducting material arranged alongside each other, and insulating material surrounding the electrodes. An impedance reducing layer of metal or metal oxide nano-structures is deposited on tips of the wire electrodes at a first end of the bundle. A functionalization layer is deposited on the impedance reducing layer at the first end of the bundle. Such a probe is particularly useful for electrochemical sensing applications such as neuronal scanning.

A surface treatment agent which is chromate-free and which can impart excellent coating adhesion and corrosion resistance to a metal material (in particular, a metal material treated with a phosphate), a surface treatment method that uses the surface treatment agent, and a surface treated metal material that is treated using the method are provided. The agent is for a metal material and contains a water-soluble ethylene glycol monoalkyl ether. It is preferable for this surface treatment agent to contain at least one type of metal compound selected from among a water-soluble vanadium compound, a water-soluble titanium compound, a water-soluble zirconium compound and a water-soluble hafnium compound.

A surface treatment agent which is chromate-free and which can impart excellent coating adhesion and corrosion resistance to a metal material (in particular, a metal material treated with a phosphate), a surface treatment method that uses the surface treatment agent, and a surface treated metal material that is treated using the method are provided. The agent is for a metal material and contains a water-soluble ethylene glycol monoalkyl ether. It is preferable for this surface treatment agent to contain at least one type of metal compound selected from among a water-soluble vanadium compound, a water-soluble titanium compound, a water-soluble zirconium compound and a water-soluble hafnium compound.

Described herein is a method for substantially nickel-free phosphating of a metallic surface, wherein a metallic surface, optionally after cleaning and/or activation, is first treated with an acidic aqueous phosphating composition that includes zinc ions, manganese ions, and phosphate ions, and is optionally rinsed and/or dried, and is thereafter treated with an aqueous after-rinse composition that includes at least one kind of metal ion selected from the group consisting of the ions of molybdenum, copper, silver, gold, palladium, tin, antimony, titanium, zirconium, and hafnium and/or at least one polymer selected from the group consisting of the polymer classes of the polyamines, polyethyleneamines, polyanilines, polyimines, polyethyleneimines, polythiophenes, and polypryroles and also mixtures and copolymers thereof, with both the phosphating composition and the after-rinse composition being substantially nickel-free.

Described herein is a method for substantially nickel-free phosphating of a metallic surface, wherein a metallic surface, optionally after cleaning and/or activation, is first treated with an acidic aqueous phosphating composition that includes zinc ions, manganese ions, and phosphate ions, and is optionally rinsed and/or dried, and is thereafter treated with an aqueous after-rinse composition that includes at least one kind of metal ion selected from the group consisting of the ions of molybdenum, copper, silver, gold, palladium, tin, antimony, titanium, zirconium, and hafnium and/or at least one polymer selected from the group consisting of the polymer classes of the polyamines, polyethyleneamines, polyanilines, polyimines, polyethyleneimines, polythiophenes, and polypryroles and also mixtures and copolymers thereof, with both the phosphating composition and the after-rinse composition being substantially nickel-free.

An electrocoat system for electrodeposition is described. The system includes an inorganic bismuth-containing compound or a mixture of inorganic and organic bismuth-containing compounds. The system demonstrates a high degree of crosslinking and produces a cured coating with optimal crosslinking and corrosion resistance.

An electrodeposition bath, water-washing baths, a first filtration membrane which feeds filtrate and concentrated-solution obtained by filtering electrodeposition-solution in the electrodeposition bath to the water-washing bath in a last stage and the electrodeposition bath, a feed system that feeds filtrate-water obtained by performing ultrafiltration or microfiltration on water after water-washing in the water-washing bath, a second filtration membrane which feeds filtrate and concentrated-solution obtained by filtering the filtrate-water fed by the feed system to the water-washing bath in the last stage and one of the electrodeposition bath and a water-washing bath other than the water-washing bath in the last stage, respectively, and a flow rate adjustment unit that adjusts a feed amount of each of the filtrate obtained by filtration by the first filtration membrane and the filtrate obtained by filtration by the second filtration membrane to the water-washing bath in the last stage are included.

The present invention is directed to an electrodepositable coating composition comprising a main vehicle comprising a phosphatized epoxy resin, a plasticizer, and a curing agent, wherein the main vehicle comprises a low-VOC main vehicle. The present invention is also directed to coatings and coated substrates.

An object of the present invention is to provide a method for forming a multilayer coating film, the method capable of achieving excellent finished appearance and excellent corrosion resistance without affecting electrodeposition coatability even when a part or all of the water-washing step is omitted after chemical conversion treatment, and to provide a coated article. The invention provides a method for forming a multilayer coating film, comprising forming a chemical conversion coating film and an electrodeposition coating film on a metal substrate by Step 1 of immersing a metal substrate in a chemical conversion treatment solution to form a chemical conversion coating film, and Step 2 of omitting a part or all of the water-washing step, and performing electrodeposition coating on the metal substrate using a cationic electrodeposition coating composition to form an electrodeposition coating film, wherein the chemical conversion treatment solution contains less than 500 ppm of sodium ions on a mass basis, and hexafluorozirconic acid. The chemical conversion treatment solution preferably contains no less than 5 ppm to less than 50 ppm of sodium ions, no less than 5 ppm to less than 90 ppm of calcium ions, less than 100 ppm of potassium ions, and less than 90 ppm of magnesium ions, on a mass basis; and is used continuously.

An object of the present invention is to provide a method for forming a multilayer coating film, the method capable of achieving excellent finished appearance and excellent corrosion resistance without affecting electrodeposition coatability even when a part or all of the water-washing step is omitted after chemical conversion treatment, and to provide a coated article. The invention provides a method for forming a multilayer coating film, comprising forming a chemical conversion coating film and an electrodeposition coating film on a metal substrate by Step 1 of immersing a metal substrate in a chemical conversion treatment solution to form a chemical conversion coating film, and Step 2 of omitting a part or all of the water-washing step, and performing electrodeposition coating on the metal substrate using a cationic electrodeposition coating composition to form an electrodeposition coating film, wherein the chemical conversion treatment solution contains less than 500 ppm of sodium ions on a mass basis, and hexafluorozirconic acid. The chemical conversion treatment solution preferably contains no less than 5 ppm to less than 50 ppm of sodium ions, no less than 5 ppm to less than 90 ppm of calcium ions, less than 100 ppm of potassium ions, and less than 90 ppm of magnesium ions, on a mass basis; and is used continuously.