Patent ID: 6953768

Claim:
A multi-component catalyst structure for the polycondensation of bis-hydroxy-ethyl terephthalate to produce polyethylene terephthalate comprising the element germanium in an amount of from 1 part per million to 200 parts per million, and one or more catalyst enhancers selected from the group of elements consisting of aluminum in an amount of from 1 part per million to 400 parts per million, silicon in an amount of from 1 part per million to 400 parts per million, molybdenum in an amount of from 1 part per million to 200 parts per million, manganese in an amount of from 1 part per million to 400 parts per million, lithium in an amount of from 1 part per million to 200 parts per million, and combinations thereof, except for a combination of germanium and lithium, wherein said elements are in the form of compounds, salts, compositions, oxides or organic complexes.