Optical components consisting of aromatic polyesters molded in the form of an optical lens
AssigneeBayer Aktiengesellschaft
InventorsHarald Medem, Dieter Freitag, Hans Hespe, Carl Heynemann
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Abstract
Thermoplastic aromatic polyesters comprising cocondensed bisphenol residues generally have a refractive index n.sub.d of from 1.60 to 1.66, an Abbe coefficient v.sub.d 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.
Claims4
An optical component consisting essentially of a thermoplastic aromatic polyester molded in the form of an optical lens, said polyester having a relative viscosity of from 1.18 to 1.42 when measured at 25.degree. C. in methylene dichloride at a concentration of 5 g/l and comprising structural units corresponding to the formula
- wherein R is ##STR8## --O--, --CO--, --SO.sub.2 --, a bond, ##STR9## R.sup.1 and R.sup.2 are selected from the group consisting of chlorine, methyl, hydrogen and bromine;
- R.sup.3 and R.sup.4 are selected from the group consisting of hydrogen, alkyl having 1 to 6 carbon atoms and aryl having 5 to 12 carbon atoms;
- n is an integer of from 4 to 11 and Ar is ##STR10## in a molar ratio of from 30:70 to 70:30.
Dependencies are inferred from the claim text.