Multilayer Transparent, Biaxially Oriented Polyester Film
October 17, 2006
A multilayer, transparent, biaxially oriented polyester film made from at least one base layer has been issued a patent. It comprises at least 80% by weight of thermoplastic polyester and from, applied to this base layer, at least one transparent, polyester high-gloss outer layer. The transparent outer layer also comprises an amount in the range from 0.05 to 0.5% by weight, based on the total weight of the outer layer, of a single pigment system that has the following features: a) the median grain diameter (d50) is in the range from 1.5 to 5 Ìm; b) the spread of the distribution of the grain size, expressed by the SPAN 98, is less than or equal to 1.9 and the packaging film exhibits an average surface roughness, Ra, of 35 to 150 nm, a haze of less than 2.5% and a gloss of greater than 170 measured at 20°.