Abstract: Provided is an insulated wire that can realize a high corona inception voltage and that can satisfy required properties such as heat resistance and a mechanical strength. A polyimide resin varnish containing, as a main component, a polyimide precursor resin obtained by allowing an aromatic diamine to react with an aromatic tetracarboxylic dianhydride, wherein the aromatic diamine includes a first aromatic diamine having an aromatic ether bond and three or more benzene rings, and a second aromatic diamine represented by formula (2) below, and an imide group concentration after imidization of the polyimide precursor resin is 25% or more and 35% or less. (In the formula, R represents CH2 or O.

Abstract: There is disclosed an insulated wire comprising a conductor, a primer layer coating the conductor, and an insulating layer coating the primer layer. The primer layer is formed by curing an epoxy resin.

Abstract: The present invention provides an excellent method for detecting a leak hole, the method being advantageous in: that a leak hole can be surely detected when any fluid present in the outside of a tank is caused, by internal decompression of the tank, to infiltrate into any fluid in the inside of the tank through the leak hole; that any leak hole present at any portion of the entire structure of a tank can be detected; and that the required testing time can be greatly shortened.

Abstract: [PROBLEMS] To provide a precoated metal sheet allowing to skip postcoating after press working that realizes high whiteness degree and excels in bright reflectivity. [MEANS FOR SOLVING PROBLEMS] A white precoated metal sheet of 80 or higher postcoating whiteness degree in terms of L-value of Hunter Lab color system, comprising a metal sheet provided with two or more coating layers, wherein when the superior layer coating refers to the coating constituting the outermost surface layer and the inferior layer coating refers to the coating interposed between the superior layer coating and the metal sheet, the content of white pigment in the inferior layer coating is in the range of 40 to 60 mass % while the content of white pigment in the superior layer coating is in the range of 5 to 25 mass % so as to excel in bright reflectivity.

Abstract: A heat-resistant resin varnish characterized by comprising a polyamideimide resin whose terminal isocyanate group is blocked with a blocking agent and a polyamic acid, which is freed from viscosity increase even without employing any complicated step such as heating or cooling and which is easily applicable to a substrate and can form, through curing, films having excellent strength and elongation (toughness) equivalent to those of polyimide resin; heat-resistant resin films which are made of a heat-resistant resin formed by baking the varnish and have excellent toughness; heat-resistant composites having the heat-resistant resin films; and insulated wire which is covered with an insulating coating film made from the varnish through curing and having excellent toughness and which can be easily manufactured at a low cost.

Abstract: This invention provides a precoated metal plate that is improved in color shading prevention and adhesion and is produced by simultaneous multilayer coating. In the precoated metal plate, the center line average roughness Ra in the coating film interface is not less than 0.3 ?m, and the maximum height from the waviness center line in the interface is not more than 50% of the layer thickness. There are also provided a top clear coated metal plate, which comprises a clear layer as an upper layer, has an interfacial center line average roughness Ra of 0.3 to 0.

Abstract: There are provided a new visible ray reflection plate capable of making the light from a lighting device and an electric/electronic device emitting a light signal brighter and an electric/electronic device using the new visible ray reflection plate. The visible ray reflection plate 1 includes a white resin sheet 5 superimposed on a metal plate 3 which may be plated wherein the area ratio of air bubbles existing at the boundary between the white resin sheet 5 and the metal plate 3 which may be plated is not greater than 5%. Alternatively, the visible ray reflection plate 1 includes a white resin sheet 5? having a visible ray diffuse reflectance of 0.07 or above at the surface of 555 nm and infrared total radiation ratio 0.60 or above at the area of the wave number 600 to 3000 cm?1 measured at a predetermined temperature from 80 degrees C. to 200 degrees C. which resin sheet is arranged on one side of the metal plate 3 which may be plated.