Nihon Parkerizing Co., Ltd.

Oxy Metal Industries Corporation

Asahi Glass Company, Limited

Henkel Corporation

Yasunobu Matsushima

Shigeo Tanaka

Masanori Suzuki

Hideaki Kaneko

Tomoyuki Aoki

Kuniji Yashiro

Kentaro Nagano

Haruyoshi Terada

Kazuyuki Akeyoshi

Ryuji Kojima

Nobuyuki Oda

Shoji Shimada

Yokichi Sato

Kuniharu Matsumoto

Kazuhiro Ishikura

Akira Niizuma

Katsuyoshi Noji

Hiroyoshi Nakagawa

Yohji Ono

Yoshio Moriya

Takayuki Tobita

Yasuo Imai

Kouji Hetsugi

Sakae Sonoda

Yoshihiko Sawasaki

Kouji Kaburagi

Hideo Oka

This invention concerns a humidity sensor wherein a chemical conversion coating, giving attention to the property that it undergoes an impedance decrease with adsorption of moisture, is used as humidity sensing element which is characterizied by an extremely short electrode distance, greatly improved sensitivity, high speed response, stable performance over a long period of time, high reliability and cheaper production cost. The principal point that characterizes the humidity sensor in this invention is that the chemical conversion coating deposited on the metal surface with or without an electrolysis application, is made usable as a humidity sensing element. For the chemical conversion coating, such coatings as phosphate, oxalate, titanium fluoro-complex, chromium phosphate and non-chromium types are used. On top of this chemical conversion coating, application of a humidity sensing film is effected to further improve humidity sensing performance.

Humidity sensor

A conversion coating, predominantly consisting of tin phosphate, can be deposited on steel or tin plated steel surfaces by contact with a solution containing phosphate ions, tin ions, an oxidizing agent such as chlorate, and a chelating agent for the tin ions, the latter to prevent the rapid loss of tin from the solution that otherwise would occur. A coating that confers excellent resistance to corrosion in hot water is formed on drawn and ironed thinly tin plated cans.

Conversion coating solution for treating metal surfaces

A method of producing titanium and titanium alloys having improved lubricity and cold working characteristics includes immersing titanium or titanium alloy as the cathode in an electrolytic conversion coating bath containing acidified zinc phosphate and forming a zinc phosphate coating on the titanium or titanium alloy by maintaining electrolysis conditions in the bath. Further improvements are achieved by pretreatment of the titanium or titanium alloy with a surface adjustment agent prior to immersion in the electrolytic conversion coating bath. The products are further treated with conventional lubricants and exhibit improved working characteristics.

Process for treatment of titanium and titanium alloys

One side surface of a strip of metal is contacted with a surface of a molten metal bath which is locally raised under ultrasonic vibration whereby a continuous coating is attained on one side only. A tool for imparting the ultrasonic vibration to a bath is immersed near the bath surface and the ultrasonic vibrator connected to the tool is contained in hollow holding means dipped in the bath. In accordance with the apparatus of the present invention, the worn tool can be exchanged for a short time and the molten metallic coating on one side only of the strip of metal can be attained for a long time.

One side surface molten metallic coating apparatus

A conversion coating solution for treating metallic surfaces is able to form conversion coating films having excellent anticorrosiveness and giving good adhesiveness and gloss to the overcoating. The conversion coating solution has a pH value of 5.5 to 6.5 and contains 0.1 to 50 g/liter as phosphate ion of acid salts of alkali phosphates, 0.01 to 0.5 g/liter of stannous ion and 2 to 12-fold by weight as much fluorine ion as the stannous ion. The conversion coating solution may be further combined with 0.2 to 5 g/liter of at least one of pyrazole compounds, hydroxylamine compounds and hydrazine compounds.

Conversion coating solution for treating metallic surfaces

Disclosed is a process wherein a conversion coated zinc or zinc alloy surface is post-treated with an aqueous solution comprising at least 0.02 g/l titanium ion and at least 0.1 g/l of an adjuvant selected from phosphoric acid, phytic acid, tannin, the salts and esters of the foregoing, and hydrogen peroxide.

Post treatment of conversion-coated zinc surfaces

Disclosed is a composition and process useful in forming a nickel phosphate coating on an iron or steel surface.

Formation of nickel phosphate coatings on iron or steel

Disclosed is a process for treating aluminum wherein the surface is contacted with a solution containing phosphate, a tannin, titanium and fluoride prior to inking or lacquering. The process produces a coating exhibiting adhesion, color and corrosion resistance comparable to that obtained via conventional chromium-based processes without creating the pollution problems of chromium disposal.

Process for treating aluminum cans

Growing community of inventors

Kawasaki, Japan

Yasunobu Matsushima