Patent ID: 6926854

Claim:
A manufacturing method for polyester fine denier multifilament, which is heating polyester polymer of inherent viscosity(IV) 0.5˜0.7 and melting point of 245˜265° C. to melt, filter and extruding in constant amount to obtain polyester fine denier multifilament, characterized in comprising the following steps: a. uniformly spinning said constant amount extruded polyester melt through a multi-layer annularly arranged spinneret orifices to obtain the filament tow, wherein the diameter of outermost layer orifice is set as D 2 mm, and the diameter of innermost layer orifice is set as D 1 mm; b. passing said spun filament tow under spinneret through a protective delay shroud of length L s mm and a cylindrical quenching air tube of length L q mm and diameter of D 0 mm which offers the radial outer-flow quenching air at wind speed of 0.2-0.6 meter/second to said filament tow from the outer side of said cylindrical quenching air tube to uniformly cooled to below glass transition point (T g ) of said polyester polymer for bundling; c. said D 2 , D 1 , D 0 , L s , L q satisfying the following requirements: (i) D 2 −D 1 <20 (mm) (ii) 12<D 1 −D 0 <33 (mm) (iii) 2<L s <20 (mm) (iv) 15<L q <40 (cm) d. winding said filament tow at the speed of 1800 to 3000 meter/minute.