Thin-foil fabrication.

A method has been developed to produce seamless, freestanding plastic cylinders with dimensions up to 18 cm in diameter, 4 cm in height and with mass density from 15 mug/cm to 300 mug/cm (approximately 0.15 to 3 mu thick). The polyvinyl formal resin may be subsequently coated with a variety of material by vapor deposition. The method employs standard thin-foil fabrication techniques modified for use in cylindrical geometry and results in uniform reproducible cylinders.