Abstract: A method of producing a steel sheet coated with a fluororesin film by heat-fusing the fluororesin film onto a surface of the steel sheet, comprising heating the surface of the steel sheet to a temperature higher by 30-120 degrees C. than a melting point of the fluororesin of the fluororesin film, and contact bonding the fluororesin film onto the steel sheet surface between a pair of rolls, while a surface of a roll facing the fluororesin film, in the pair of rolls, is heated to a temperature lower by 100-210 degrees C. than the melting point of the fluororesin of the fluororesin film.

Abstract: An apparatus for and a method of measuring at least one painted layer formed on a sample to be analyzed, which sample may be, for example, a galvanized steel including a substrate having the painted layer formed thereon with or without an intervention of a primer coated layer. In the practice of the invention, radiation is directed onto a surface of the painted layer so as to excite the sample. The intensity of resultant Compton scattering rays, the intensity of resultant fluorescent X-rays emitted from zinc contained in a plated zinc and the intensity of resultant fluorescent X-rays emitted from strontium contained in the primer coated layer are measured, and also the absorption of the fluorescent X-rays are taken into consideration, to provide a basis for calculation of the amount of paint coating forming the painted layer. In this way, the amount of primer and paint material both applied to the galvanized steel can be easily measured on a non-destructive basis.

Abstract: A roll for hot dipping bath includes at its outer peripheral surface at least one spiral groove for the discharge of dross. In this roll, the outer peripheral surface existing between the adjoining groove portions includes a rough surface, capable of applying a molten metal composition to a sheet of metal without transferring a groove mark to the sheet.