Patent ID: 7893135

Claim:
A concentrate comprising: C.1) from 98 wt. % to 70 wt. % (based on the sum of the wt. % of C.1)+C.2)) of polyalkylene terephthalate or a mixture of at least two polyalkylene terephthalates and C.2) from 2 wt. % to 30 wt. % (based on the sum of the wt. % of C.1)+C.2)) of at least one compound selected from the group consisting of C.2.1) the compound of formula (IV) HO 2 C—CH 2 —CH 2 —P(═O)(OH) 2 (IV) C.2.2) the compound of formula (V) C.2.3) the compound of formula (VI) C.2.4) ortho-phosphoric acid H 3 PO 4 (VII) C.2.5) the compound of formula (VIII) and C.2.6) phosphorous acid H 3 PO 3 (IX).