Patent · US Expired

Purification of polycarbonate, polyester carbonate or polyester waste

US5214072A · kind A · utility

10Cited by

1References

1Claims

0Family size

Assignee

BAYER HEALTHCARE LLC · DE

Inventors

Gerhard Fennhoff · Willich, DE
Wolfgang Jakob · Moers, DE
Manfred Ehlert · Dormagen, DE

Key dates

Filing date	Oct 8, 1992
Grant date	May 25, 1993
Priority date	—
Expiry date	Oct 8, 2012

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY02W30/62
WIPO fieldOther special machines
WIPO sectorMechanical engineering

Abstract

A process for the purification of waste of thermoplastic resins containing at least one member selected from among aromatic polycarbonates, aromatic polyester carbonates and aromatic polyesters and at least one of aluminum, lacquers and dyes which waste accumulates in the production of optical moldings is disclosed. The process which entails size reduction of the waste, chemical wash and filtering steps yields purified resins suitable for thermoplastic processing.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.