Lighter than air balloon made from a biaxially oriented polyester film

A long life balloon formed from a lamination. The lamination includes a polyester film with a total thickness of 4 μm to 12 μm. The polyester film includes a biaxially oriented polyester core layer and at least one amorphous copolyester skin layer. The lamination also includes a sealant layer and a gas barrier layer on an opposite side of the polyester film from the sealant layer. The oxygen transmission rate of the balloon is less than 0.1 cc/100 sqin/day, a bonding strength of the gas barrier layer to the surface of the polyester film is more than 300 g/in at dry conditions, a sealing strength of the balloon is more than 3.5 kg/in, and a floating time of the balloon is more than 20 days.