| abstract |
This disclosure relates to a solution made from an aromatic copolyamide, a transparent film, and a display element, optical element or illumination element using the solution and / or film. The copolyamide containing the pendant carboxyl group may be a polyol having at least one of cresol, xylene, N, N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidinone (NMP), dimethylsulfoxide (DMSO) Other solvent or a mixed solvent having more than two solvents. When the film is thermoset at a temperature near the copolymer glass transition temperature, after curing, the polymer film exhibits a transmittance> 80% at 400 to 750 nm, a coefficient of thermal expansion of less than 20 ppm, and solvent resistance . |