Patent ID: 9074407
Filing Date: 2015-07-07
Classification: B29C,B29K,B29L,B32B,C08K,E06B,Y10T

Abstract:
1. A biaxially oriented polyester film comprising three layers, said film comprising a carbon-black-filled exterior outer layer and two TiO 2 -containing layers, wherein one of the TiO 2 -containing layers is a white outer layer disposed opposite the carbon-black-filled outer layer on a second TiO 2 -containing layer, the second TiO the thickness of each of the outer layers is from 4 to 15 μm, the thickness of the base layer is ≧the total of the thicknesses of the outer layers and at least 50% of the film total thickness, the white outer layer comprises polyester and at least 15% by weight of TiO the base layer comprises polyester and at least 4% by weight of TiO the carbon-black filled outer layer comprises polyester and from 3 to 15% by weight of carbon black, and the standard viscosity value of the film is at least 600, where all % by weight data are based on the weight of the respective layer, the film has a Berger whiteness of at least 90 on one side of the film and further comprises a flame retardant.