Patent ID: 8722200

Claim:
A laminated plate, comprising: a core polypropylene-based resin in an unfoamed state and having a foamable property; and an aluminum alloy plate laminated on each of two sides of the core polypropylene-based resin in the unfoamed state such that strain distribution of the alloy plates will be homogenized with the polypropylene-based resin in the unfoamed state upon shaping of the alloy plates with the core polypropylene-based resin in the unfoamed state disposed between the alloy plates to a prescribed shape via a cold forming process, wherein: a total thickness of the laminated plate is 3.4 mm or less; a plate thickness of each aluminum alloy plate is from 0.05 to 1.0 mm; a plate thickness of the core polypropylene-based resin in the unfoamed state and having foamable property is from 0.5 to 1.4 mm; and each aluminum alloy plate is composed of a temper treated material selected from an O material, an H22 material to an H24 material, an H32 material to an H34 material and a T4 material in terms of a temper designation specified according to the JIS H0001 standards; and wherein the core polypropylene-based resin in the unfoamed state disposed between the alloy plates is capable of foaming upon application of heat to the core polypropylene-based resin in the unfoamed state.