Search International and National Patent Collections

1. (WO2018054847) TRANSPARENT MOULDED PARTS HAVING REDUCED THICKNESS

Pub. No.:    WO/2018/054847    International Application No.:    PCT/EP2017/073506
Publication Date: Fri Mar 30 01:59:59 CEST 2018 International Filing Date: Tue Sep 19 01:59:59 CEST 2017
IPC: C08G 64/06
B29C 45/00
C08K 5/00
F21S 8/10
Applicants: COVESTRO DEUTSCHLAND AG
Inventors: DÖBLER, Martin
WEHRMANN, Rolf
BOUMANS, Anke
WINKLER, Lucia
BURGER, Martin
Title: TRANSPARENT MOULDED PARTS HAVING REDUCED THICKNESS
Abstract:
The invention relates to the use of a composition A based on aromatic polycarbonate, containing a) aromatic polycarbonate, wherein the polycarbonate has an average weight-average molecular weight Mw of 22000 g/mol to 27000 g/mol, determined by means of gel permeation chromatography according to DIN 55672-1:2007-08, and calibrated in relation to bisphenol A-polycarbonate standards using dichloromethane as an eluent, and wherein the polycarbonate has 0 to max. 19 mol% carbonate units of formula (1) where R1, R2, R3, R4, R5, R6, R7 and R8 independently represent H or C1- to C6-alkyl, and b) 0 to less than 0.2 wt.% of a UV absorber or a UV absorber mixture, in relation to the total weight of the polycarbonate composition, in order to increase the flow path-wall thickness ratio in the production of a moulded part by means of injection moulding, as well as correspondingly producible thin-walled transparent moulded parts, preferably lamp covers, in particular headlamp covers, having a maximum wall thickness of 3mm, in particular those with a thickness of max. 1.9mm. The invention also relates to headlamps comprising these headlamp covers, and an LED light source, and a method for producing the headlamp covers.