Patent ID: 7686987
Filing Date: 2010-03-30
Classification: B29C,B29D,B29K,B29L,B32B,C08J,C09K,G02B,Y10T

Abstract:
1. A coating method for forming a polycarbonate film consisting essentially of the steps of: (a) applying a multi-layer composite comprising a liquid polycarbonate/solvent mixture onto a moving, discontinuous carrier substrate, where the multi-layer composite comprises multiple layers of coating fluids, each layer comprising a polycarbonate resin dissolved in solvent, wherein the viscosity of each layer of the multi-layer composite is less than 5,000 cp and the lowermost layer of the multi-layer composite comprises the polycarbonate in a concentration adjusted to achieve a viscosity of less than 100 cp; and (b) drying the liquid polycarbonate/solvent mixture to substantially remove the solvent to obtain a residual solvent content of less than 5% by weight yielding a composite of a dried polycarbonate film having an in-plane retardation of less than 20 nm adhered to the discontinuous carrier substrate, the polycarbonate film being releasably adhered to the discontinuous carrier substrate with an adhesive strength of less than about 250 N/m thereby allowing the polycarbonate film to be peeled from the discontinuous carrier substrate, wherein all coated layers of said dried polycarbonate composite film have substantially the same polycarbonate.