Polyester filament having excellent antistatic properties and process for preparing the same

Claim 1

A polyester filament having excellent antistatic properties which comprises a composition of (1) a polyester selected from one group consisting of polyethylene terephthalate, polytetramethylene terephthalate, polyethylene-2, 6-napthalene dicarboxylate, poly-1,44-cyclohexanedimethylene terephthalate poly[ethylene-1,2-bis(phenoxy)ethane-p, p'-dicarboxylate] and poly-p-ethylene oxybenzoate, and (2) a polyether-polyester block copolymer consisting of polyalkylene glycol and polyester wherein at least 40 mol % of the polyester segment of said polyether-polyester block copolymer comprises polyester constituents synthesized from at least one member selected from the group consisting of: A. an aliphatic or alicyclic oxycarboxylic acid having at least 2 carbon atoms and ester-forming derivatives thereof, B. an aliphatic or alicyclic dicarboxylic acid having at least 3 carbon atoms and ester-forming derivatives thereof, C. an aromatic dicarboxylic acid or oxycarboxylic acid having a group ether-linked with an aromatic ring having a carboxyl group and ester-forming derivatives thereof, D. an aromatic dicarboxylic acid or oxycarboxylic acid having a substituent group at the orthoposition toward a carboxyl group and ester-forming derivatives thereof, and E. an aliphatic or alicyclic glycol having at least 3 carbon atoms, wherein said polyester filament includes 0.01-5.0% of said polyalkylene glycol by weight of said polyester filament, and has a specific resistance less than 10 11 Ω.cm and said polyether-polyester block copolymer is dispersed as fine striae along the filament axis, at least one of said striae being substantially endless.