| abstract |
PURPOSE: To obtain a polyester with excellent spinnability and drawability capable of giving high-quality polyester fiber free from defects such as fiber rupture and fluff, by incorporating the original polyester with specific amount of titanium dioxide having each specific particle size, size distribution and coarse particle content. n CONSTITUTION: The objective polyester can be obtained by incorporating (A) a melt-spinnable polyester (e.g. polyethylene terephthalate) with (B) 0.01W3wt% of titanium dioxide having the following characteristics (i) average particle size: ≤0.50 (pref. 0.1W0.5)μm (ii) size distribution ratio [γ] in the size distribution represented in terms of the cumulative weight of sedimented particles produced by centrifugal sedimentation process: ≤2.3 (pref. 1.4W2.2) (iii) content of coarse particles with a size ≥1.5μm: ≤0.5wt% based on the whole particle weight. Furthermore, said titanium dioxide preferably contains ≥0.25 (pref. 0.25W1)wt% of P on a P 2 O 5 basis and ≥0.1 (pref. 0.1W0.3)wt% of K on a K 2 O basis. n COPYRIGHT: (C)1985,JPO&Japio |