The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 27, 2011
Filed:
Oct. 25, 2007
Heinz Pudleiner, Krefeld, DE;
Wolfgang Ebert, Krefeld, DE;
Alexander Meyer, Düsseldorf, DE;
Klaus Meyer, Dormagen, DE;
Alexander Karbach, Krefeld, DE;
Franky Bruynseels, Gillis-Waas, BE;
Heinz Pudleiner, Krefeld, DE;
Wolfgang Ebert, Krefeld, DE;
Alexander Meyer, Düsseldorf, DE;
Klaus Meyer, Dormagen, DE;
Alexander Karbach, Krefeld, DE;
Franky Bruynseels, Gillis-Waas, BE;
Bayer MaterialScience AG, Leverkusen, DE;
Abstract
Linear polycarbonate resin virtually free of surface defects that impair the suitability of the resin for demanding optical application is disclosed. Also disclosed is a process for the manufacture of the resin. The surface defects included in the resin are in the form of transparent fluorescing particles, the particle count of which portion that are 15 and 250 μm in size, is up to 1.8 counts/g, said count being determined by exciting the residue remaining after filtering a solution of said polycarbonate in methylene chloride through a Teflon filter of 5 μm pore size at a wavelength of 400-440 nm, 25× overall magnification and illumination time of 40 millisec. The polycarbonate is suitable for making films of improved optical properties.