PURPOSE: To prevent the welding of studs from adversely affecting and improve the heat fusion property and heat stability property of a building material for use in interior and external trimming by welding studs to a metal sheet having a thickness of a specific value or more in which at least one face is covered with a resin film having a melting point of a specific temperature or higher.
CONSTITUTION: A resin film having a melting point of 150°C or higher, high heat stability and less thermochromism, for example a fluorine-containing resin type film or the like is joined to at least one face of a metal sheet of iron or aluminum type or the like having a thickness of 1mm or more according to a method for melt adhesion under heating and the like. To the so obtained laminate of metal and resin film, studs are welded by the use of a welding gun and machine. The metal sheet having so welded studs is free from dents that would occur on studs at the time of welding thereof, changes of the film incidental to the fusion or discoloration such as burn. Furthermore, the resin film layer is a smooth, continuous homogeneous layer which does not permit the chemical substances to permeate into the metal layers, capable of improving the durability.
MIMURA IKUO
HABASAKI YASUHARU
SUGIYAMA TADASHI
MURAMOTO TADANORI
