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:
Apr. 28, 1998
Filed:
Feb. 06, 1997
Heinz-Dieter Schumann, Maintal, DE;
Ulrich Thiele, Bruchkoebel, DE;
Zimmer AG, Frankfurt, DE;
Abstract
A process for the acceleration of the polycondensation of polyester made by the esterification of at least one dicarboxylic acid with at least one diol, precondensation, melt phase polycondensation, granulation, crystallization and solid phase polycondensation comprising the addition, prior to the precondensation reaction, of from about 30 to about 900 ppm phosphorus in relation to the polyester in the form of carboxy phosphonic acid of the formula: ##STR1## wherein, R is selected from the group consisting of C.sub.1-10 -alkylene, C.sub.1-10 -cycloalkylene, and C.sub.6-10 -arylene and R.sup.1, R.sup.2, and R.sup.3 are selected from the group consisting of hydrogen, C.sub.1-10 -alkyl, C.sub.1-10 -cycloalkyl, and C.sub.6-10 -aryl, provided that at least two of R.sup.1, R.sup.2, and R.sup.3 are hydrogen.