Patent ID: 6410678
Filing Date: 2002-06-25
Classification: C08G,G11B

Abstract:
An aromatic polycarbonate which comprises a main recurring unit represented by the following formula (1): wherein R1 and R2 are each independently alkyl group having 1 to 20 carbon atoms, alkoxy group having 1 to 20 carbon atoms, cycloalkyl group having 6 to 20 carbon atoms, aryl group having 6 to 20 carbon atoms, cycloalkoxy group having 6 to 20 carbon atoms or aryloxy group having 6 to 20 carbon atoms, m and n are each independently an integer of 0 to 4, and X is a single bond, oxygen atom, carbonyl group, alkylene group having 1 to 20 carbon atoms, alkylidene group having 2 to 20 carbon atoms, cycloalkylene group having 6 to 20 carbon atoms, cycloalkylidene group having 6 to 20 carbon atoms, arylene group having 6 to 20 carbon atoms or alkylene-arylene-alkylene group having 6 to 20 carbon atoms, and terminal groups consisting essentially of aryloxy groups (A) and phenolic hydroxyl groups (B), the (A)/(B) molar ratio being 95/5 to 40/60, and which has a melt viscosity stability measured under a nitrogen stream at a shear rate of 1 rad./sec and 300Â° C. for 30 minutes of 0.5% or less, a sodium metal element content of 100 ppb or less and a content of each of first elements, Ni, Pb, Cr, Mn and Fe of 70 ppb or less, and wherein the relationship between the concentration (H) (eq./ton-polycarbonate) of terminal hydroxyl groups and the total content (&Sgr;first elements) (ppb) of the first elements is represented by (H)&lE;&Sgr;first elements.