Polyester films containing precipitated silica particles and calcined china clay

摘要

The present invention relates to films or sheets of linear polyester having incorporated therein a combination of precipitated silica particles and calcined clay having certain particle sizes and present in specific amounts based upon the weight of the polyester film. The addition of these fillers improves several properties of the film, including the handleability while maintaining acceptable optical clarity and transparency and to the method of making such films or sheets.