Patent ID: 8551281

Claim:
A method for producing a laminated metal sheet comprising a metal sheet and a high melting point film having a melting point MP1 and a low melting point film having a melting point MP2 on opposite sides of said metal sheet, wherein MP1 is substantially higher than MP2, the method comprising the steps of: heating the metal sheet to a temperature Ti at lamination roll inlet side, wherein Ti is MP 1+(50° C. or less); and laminating the high melting point film and the low melting point film on the metal sheet by passing the metal sheet, the high melting point film and the low melting point film through a pair of lamination rolls at a sheet running speed V; low melting point film is made to a thickness d2 defined by the following equation (1): d 2(μm)≧ k (ΔMP−Δ T )/ V (1) where, ΔMP=MP1−MP2, wherein ΔMP is 46° C. or higher MP 1: melting point of high melting point film (° C.) MP2: melting point of low melting point film (° C.) k: constant determined by said low melting point film's heat conductivity, heat capacity, and temperature, wherein k≧2[μm·m/(° C.·s)] 0<Δ T =MP1−φ·Ti≦50(° C.) Ti: metal sheet temperature at lamination roll inlet side (° C.) φ: constant determined by heat removal conditions at time of lamination wherein 0.75≦φ<1 V: sheet running speed (m/s).