Organic compounds -- part of the class 532-570 series – Organic compounds – Heterocyclic carbon compounds containing a hetero ring...
Reexamination Certificate
2005-07-12
2005-07-12
Dentz, Bernard (Department: 1625)
Organic compounds -- part of the class 532-570 series
Organic compounds
Heterocyclic carbon compounds containing a hetero ring...
C203S039000
Reexamination Certificate
active
06916939
ABSTRACT:
The present invention provides a process for production of a cyclic ester by depolymerization of an aliphatic polyester. In the process, a mixture containing the aliphatic polyester and a specific polyalkylene glycol ether, which has a boiling point of 230-450° C. and a molecular weight of 150-450, is heated under normal or reduced pressure to a temperature at which depolymerization of the aliphatic polyester takes place. Then, a substantially homogeneous solution phase, consisting of the melt phase of the aliphatic polyester and the liquid phase of the polyalkylene glycol ether, is formed. Heating of the solution phase is continued to form the cyclic ester by depolymerization and distil out the cyclic ester together with the polyalkylene glycol ether, and then the cyclic ester is recovered from the distillate. The present invention also provides a process for purification of a crude cyclic ester by use of the specific polyalkylene glycol ether described above.
REFERENCES:
patent: 2668162 (1954-02-01), Lowe
patent: 4727163 (1988-02-01), Bellis
patent: 5023349 (1991-06-01), Bhatia
patent: 5326887 (1994-07-01), DiCosimo et al.
patent: 5342969 (1994-08-01), Ford et al.
patent: 5830991 (1998-11-01), Shiiki et al.
patent: 0 789023 (1997-08-01), None
patent: 2 692263 (1993-12-01), None
patent: 09-328481 (1997-12-01), None
patent: 2000-119269 (2000-04-01), None
patent: WO 9215572 (1992-09-01), None
Hoshi Hajime
Kawakami Yukichika
Sunagawa Kazuhiko
Yamane Kazuyuki
Dentz Bernard
Dinsmore & Shohl LLP
Kureha Kagaku Kogyo K.K.
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