Chassis for small electronic device and method for forming same, and rolled aluminum alloy laminated sheet material for chassis for small electronic device

A laminated sheet material for a chassis for an electronic device, the laminated sheet material comprising:

• a rolled aluminum alloy sheet material having a thickness of from 0.5 mm to 3.5 mm and a 0.2% proof stress of 200 MPa or more, the rolled aluminum alloy sheet material including a first surface and a second surface opposite to the first surface in a thickness direction, the first surface and the second surface extending along a rolling direction of the rolled aluminum alloy sheet material, the rolled aluminum alloy sheet material having a fibrous crystalline structure extending in a direction orthogonal to the thickness direction when observed in a cross section of the rolled aluminum alloy sheet material, the cross section including fibers of the fibrous crystalline structure extending in the direction orthogonal to the thickness direction;
• a first covering material comprising a first stretched synthetic resin film and laminated on the first surface of the rolled aluminum alloy sheet material that is to be an outer surface of the chassis of the electronic device;
• a first adhesive layer provided between the rolled aluminum alloy sheet material and the first covering material to adhere to the rolled aluminum alloy sheet material;
• a second covering material comprising a second stretched synthetic resin film and laminated on the second surface of the rolled aluminum alloy sheet material that is to be an inner surface of the chassis of the electronic device;
• and
• a second adhesive layer provided between the rolled aluminum alloy sheet material and the second covering material to adhere to the rolled aluminum alloy sheet material,
• wherein the first stretched synthetic resin film of the first covering material comprises an oriented film that is peelably provided to the first surface of the rolled aluminum alloy sheet material,
• wherein the second stretched synthetic resin film of the second covering material comprises a second oriented film that is peelably provided to the second surface of the rolled aluminum alloy sheet material,
• wherein the first covering material and the second covering material are outermost layers of the laminated sheet material,
• wherein the first covering material and the second covering material are directly adhered to the rolled aluminum alloy sheet material,
• wherein the first stretched synthetic resin film and the second stretched synthetic resin film are outermost layers of the laminated sheet material,
• wherein the first covering material has a tensile strength of from 180 to 330 MPa, a tensile breaking elongation of from 80 to 180%, and a ratio of machine direction (MD)/traverse direction (TD) in tensile strength or tensile breaking elongation in a range of from 0.8 to 1.2,
• wherein the second covering material includes a film having a Young's modulus of from 30 to 400 MPa, and
• wherein the oriented film is peelably provided to the first surface of the rolled aluminum alloy sheet material to prevent the first adhesive layer from remaining on a surface of the rolled aluminum alloy sheet material when the oriented film is peeled off the rolled aluminum alloy sheet material.