Patent · US Expired

Mixtures of cyclic oligocarbonates and their manufacture

US5786440A · kind A · utility

28Cited by

3References

7Claims

0Family size

Assignee

BAYER HEALTHCARE LLC · DE

Inventors

Burkhard Kohler · Leverkusen, DE
Duane B. Priddy, Jr. · Midland, US
Yun Chen · Krefeld, DE
Harald Pielartzik · Pittsburgh, US
Robert J. Kumpf · Pittsburgh, US

Key dates

Filing date	Nov 24, 1997
Grant date	Jul 28, 1998
Priority date	—
Expiry date	Nov 24, 2017

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC08G64/28
WIPO fieldOrganic fine chemistry
WIPO sectorChemistry

Abstract

A process for the manufacture of cyclic oligocarbonate is disclosed. The process comprises a reaction of a bis-chlorocarbonic acid ester with isatinbisphenol or with a bis-chlorocarbonic ester thereof. The mixture of cyclic oligocarbonates thus prepared is useful as a precursor in the preparation of modified polycarbonate or polyester resins.

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