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. 05, 1994
Filed:
Apr. 03, 1991
Rhone-Poulenc Fibres, Lyons, FR;
Abstract
The present invention relates to a process for obtaining continuously polyethylene terephthalate modified by --SiO-- groups in a proportion of 300-700 ppm of Si during the direct esterification reaction between terephthalic acid and ethylene glycol, followed by polycondensation in a known manner by introducing methoxyethyl silicate or propyl silicate at a time when the prepolymer has a weight-average molecular mass of between 9,000 and 16,000, a polydispersity index of between 1.5 and 2, and when it is at a temperature of between 260.degree. and 290.degree. C. and at a pressure of between 1.5 and 2.5 bars, the silicate/prepolymer reaction time being at least 5 minutes. The present invention also relates to pilling-free fibres originating from the modified polyethylene terephthalate and to a process for obtaining them.