Non-Birefringent Optical Adhesives and Films
The invention pertains generally to miscible polymer blends which can be used in optical applications, particularly in liquid crystal displays and optical adhesives, in that they are essentially birefiringence-free. The polymeric blend alloy includes a first polymer having an inherent positive birefringence and a second polymer having an inherent negative birefringence, the first and second polymers being soluble within each other to predefined limits. The polymer blend is an essentially birefringence-free film layer suitable for use in liquid crystal displays which has adequate mechanical properties, such as dimensional stability, permeability to water vapor, scratch-resistance and insensitivity to temperature, in that it is possible for them to be processed continuously and flexibly to all the required shapes. The polymer blends can be prepared not only from solvent solutions, but by melt-mixing as well.
Kyu, Thein, "Non-Birefringent Optical Adhesives and Films" (1999). Polymer Engineering Faculty Research. 994.