Importance

Loading Importance Indicators...

Abstract

Relatively long plastic microfilaments are used to make reinforcing, filler materials and fabrics. A blowing gas is applied at a positive pressure to the inert surface of a liquid plastic film formed across a coaxial blowing nozzle to blow the film and form an elongated hollow tube having a thinned wall or weakened portion. An entraining fluid is directed at an angle over and around the blowing nozzle and as it passes over and around the blowing nozzle, it dynamically induces a pulsating or fluctuating pressure field at the opposite side of the blowing nozzle in the wake thereof and produces a laminar flow of entraining fluid in the vicinity of the forming elongated tube. The continued movement of the entraining fluid over the elongated tube produces asymmetric fluid drag forces on the tube, and at the thinned wall or weakened wall portion longitudinally breaks the tube to form a multiplicity of plastic microfilaments, and detaches the plastic microfilaments from the elongated tube and from the coaxial blowing nozzle and the detached microfilaments are carried away from the blowing nozzle. Quench nozzles or heating nozzles may be disposed below and on either side of the blowing nozzle to direct cooling or heating fluid at and into contact with the plastic microfilaments to cool or heat and cure, solidify and harden the plastic to form hard, smooth plastic microfilaments.

Loading the Abstract Image...

First Claim