Abstract: The process for producing polyesters, and in particular, polyethylene terephthalate (PET) which includes the use of antimony catalyst that is acidic phosphorus additive involves the addition of the catalyst prior to or together with the additive. Moreover, the amount of additive is selected so as to provide a resin that is at least substantially free of non-acidic inorganic compounds such as antimony phosphate which can be formed by the reaction of the catalyst with the additive. The process preferably includes an esterification step, a prepolymer step, and a polymerization step with the antimony catalyst being added prior to, during, or after, the esterification step while the phosphorus-containing additive is introduced prior to or during the prepolymer stage. Polyesters having low levels of elemental phosphorus are also disclosed.

Abstract: The present invention relates to a process comprises mixing, at temperatures between about about 90.degree. C. to 300.degree. C., a first reactant solution comprising less than about 5.times.10.sup.-3 moles/l of at least one antimony compound and at least one first diol having having 2 to about 16 carbon atoms with a second reactant solution comprising less than about 30.times.10.sup.-3 moles/l of at least one phosphorus stabilizer compound and at least one second diol to form sub-visual molecular aggregates comprising antimony phosphate derivatives. Sub-visual molecular aggregates comprising antimony phosphate derivatives which are stable in suspension are also disclosed.

Abstract: Disclosed herein is an esterification process characterized by the high dilution in situ addition of antimony catalyst compound and phosphorus stabilizer compound to the esterification reaction mixture. A high dilution polymerization process for producing antimony phosphate derivative-containing polymer is also disclosed. Further disclosed are high clarity polyesters containing sub visual antimony phosphate derivative particles.

Abstract: This invention relates to a polyester resin prepared by adding one or more dicarboxylic acid components to one or more glycol components containing 1,4-cyclohexanedimethanol equalling 100 mole %, the polyester resin having been prepared in the presence of a catalyst/stabilizer system consisting essentially of antimony compounds and phosphorous compounds and compounds selected from the group consisting essentially of zinc compounds, gallium compounds, and silicon compounds.

Abstract: This invention relates to a polyester resin prepared by adding one or more dicarboxylic acid components to one or more glycol components containing 1,4-cyclohexanedimethanol equalling 100 mole %,the polyester resin having been prepared in the presence of a catalyst/stabilizer system consisting essentially of antimony compounds and phosphorous compounds and compounds selected from the group consisting essentially of zinc compounds, gallium compounds, and silicon compounds.