Patent ID: 7655746

Claim:
A process for reducing the acetaldehyde content of polyesters susceptible to generation of acetaldehyde during their preparation or subsequent use, comprising preparing said polyester by a continuous melt polymerization process comprising polycondensing a polyester melt in the presence of one or more titanium polycondensation catalysts, and after the It.V. of the melt reaches at least 0.45 dL/g, adding to said polyester melt in said continuous melt polymerization process at least one additive comprising an ammonium salt of an oxyphosphorus acid compound containing an oxyphosphorus group, an amine salt of an acid compound containing an oxyphosphorus group, or mixture thereof, wherein said polyester has a final It.V. after solidification from the melt, and prior to optional solid state polymerization, of from 0.7 to 1.2 dL/g, and wherein said polyester comprises a polyethyleneterephthalate polyester.