Composite sheet material for magnetic and electronic shielding and product obtained therefrom

A composite sheet material for magnetic and electronic shielding, comprising:

• a composite sheet metal including an electrodeposited iron foil with a thickness of at least 10 .mu.m and not more than 50 .mu.m, and a pair of metal plating layers on opposite surfaces of said electrodeposited iron foil, said metal plating layers being formed of a metal selected from the group consisting of zinc, tin, nickel, chromium, copper and lead;
• and
• a covering layer formed on at least one of said pair of metal plating layers of the composite sheet metal, said covering layer comprising at least one layer of sheet material which is bonded to the respective surface of the composite sheet metal with an adhesive layer interposed therebetween, wherein said covering layer is formed on each of said pair of metal layers of the composite sheet metal, and further comprising a pressure sensitive adhesive layer formed on one of the covering layers and a release liner adhering to said pressure sensitive adhesive layer.

A composite sheet material for magnetic and electronic shielding, comprising:

• a composite sheet metal including an electrodeposited iron foil with a thickness of at least 10 .mu.m and not more than 50 .mu.m, and a pair of metal plating layers on opposite surfaces of said electrodeposited iron foil, said metal plating layers being formed of a metal selected from the group consisting of zinc, tin, nickel, chromium, copper and lead;
• and
• a covering layer formed on at least one of sad pair of metal plating layers of the composite sheet metal, said covering layer comprising at least one layer of sheet material which is bonded to the respective surface of the composite sheet metal with an adhesive layer interposed therebetween, wherein said covering layer is formed on each of said pair of metal plating layers of the composite sheet metal, one of said covering layers consisting of a flame retardant plastic sheet, the other covering layer consisting of a flame retardant foam plastic sheet.

A composite sheet material for magnetic and electronic shielding, comprising:

• a composite sheet metal including an electrodeposited iron foil with a thickness of at least 10 .mu.m and not more than 50 .mu.m, and a pair of metal plating layers on opposite surfaces of said electrodeposited iron foil, said metal plating layers being formed of a metal selected from the group consisting of zinc, tin, nickel, chromium, copper and lead;
• and
• a covering layer formed on at least one of said pair of metal plating layers of the composite sheet metal, said covering layer comprising at least one layer of sheet material which is bonded to the respective surface of the composite sheet metal with an adhesive layer interposed therebetween, wherein said covering layer is formed on one of said metal plating layers, and further comprising a pressure sensitive ahdesive layer formed on the other metal plating layer, and a release liner adhering to said pressure sensitive adhesive layer.

A corrugated packaging material for magnetic and electronic shielding, of corrugated fiberboard construction comprising at least one corrugated medium layer, and a pair of liner layers adhering to opposite surfaces of said corrugated medium layer, wherein the improvement comprises:

• said at least one corrugated medium layer or at least one of said liner layers is formed of a composite sheet metal including an electrodeposited iron foil having a thickness of at least 10 .mu.m and not more than 50 .mu.m, and a pair of metal plating layers on opposite surfaces of said electrodeposited iron foil, said metal plating layers being formed of a metal selected from the group consisting of zinc, tin, nickel, chromium, copper and lead.