| 摘要 |
PURPOSE:To obtain a welded can with a narrow welding width without having the difference in the level of a joint by providing a resin coating film with the heat-resistant decomposing property having a specific thermogravimetric reduction rate in the vicinity of a welded zone. CONSTITUTION:In the case of welding the can by the welding of metal raw material, at the time of providing the resin coating film in the vicinity of the welded zone, coating material to obtain the resin coating film with the temperature >=470 deg.C where the thermogravimetric reduction rate is made to 50% is coated in the thermogravimetric analysis (TGA) measurement under the condition of the temperature raising speed 20 deg.C/min in gaseous nitrogen current of a film sample. Then, the metal material is butt-welded by a CO2 laser. In this way, the temperature of the film and the metal plate can be arranged to the high temperature having the high laser beam absorptivity with the high efficiency and the laser beam welded can with the excellent external appearance is obtained. |
