To provide a catalyst for production of a polyester, a process for
producing a polyester using the catalyst and a titanium-containing
polyethylene terephthalate having excellent characteristics.A catalyst
for production of a polyester, characterized by comprising at least (1) a
Group 4A compound (hereinafter referred to as compound (1)), (2) a
compound of at least one element selected from the group consisting of
magnesium, calcium and zinc (hereinafter referred to as compound (2)) and
an oxygen-containing organic solvent. A process for producing a polyester
using this catalyst. A titanium-containing polyethylene terephthalate,
having characteristics represented by the following (A), (B) and (C):
(A) titanium K absorption edge: the peak intensity ratio R defined by
R=A/B exceeds 0.2, where A is the intensity of a peak having the maximum
intensity among K absorption pre-edge peaks, and B is the maximum peak
intensity of K absorption post-edge peaks in a XANES spectrum obtained by
normalizing a XAFS spectrum; (B) the amount of carboxyl end groups is
less than 35 eq/ton; and (C) the intrinsic viscosity is at least 0.5
dl/g.