Method for producing a thermoplastic plastic film, film and use thereof

摘要

A thermoplastic foil which is between 10 to 150 mm with a birefringence (Birefringence or double refraction is the decomposition of a ray of light into two rays - the ordinary ray and the extraordinary ray) which will cause a maximum displacement of 25 nm to the optical path of a perpendicular beam of light passing through the thermoplastic foil. A further characteristic of the thermoplastic foil is that there will be no region within any 12 cm diameter circle on the surface of the thermoplastic foil that will deflect a perpendicular beam of light by more than 0.8 angular minutes. The maximum vertical birefringence of the thermoplastic foil is 0.0004.