| abstract |
Thermoplastic aromatic polyesters comprising cocondensed bisphenol residues generally have a refractive index nd of from 1.60 to 1.66, an Abbe coefficient vd of from 27 to 21 and a color triplet of about 5.1, 0.1, O and are excellent starting materials for the production of optical components, particularly high quality lenses for still and cine cameras. |