Orifice assembly for extruding and attenuating essentially inviscid jets

Claim 1

An improved orifice assembly for use in the formation of fibers and filaments by extruding an essentially inviscid melt as a filamentary stream, which comprises in combination: a. a first plate; b. a second plate, said second plate being spaced beneath said first plate in a stacked relationship therewith; c. a first orifice, said first orifice being centrally disposed in said first plate; d. a second orifice, said second orifice being centrally disposed in said second plate in co-axial alignment with said first orifice, said second orifice having a nozzle configuration with a convergent entry section, an intermediate throat section and a divergent exit section, with the exit section having an included angle of divergence of between 4* to 12*; e. a substantially enclosed chamber, said chamber being defined by a gap space between the opposing faces of said first and second plates, said gap space having a vertical distance of less than five times the diameter of the throat section of said second plate orifice; f. a means for supplying an inert gas under pressure to said substantially enclosed chamber and into said second orifice.