The invention relates to a method for making a spunbonded high loft nonwoven web comprising crimped multicomponent fibers, the process comprising continuously spinning the fibers, directing the fibers to a spin-belt by deflectors and/or air streams, laying down the fibers on the spinbelt and pre-consolidating the fibers after laydown using one or more pre-consolidation rollers to form a pre-consolidated web, wherein a first component of the fibers comprises a PP homopolymer and a second component of the fibers comprises a PP/PE copolymer, wherein the pre-consolidation rollers are operated at a temperature of smaller 110 C. and/or a linear contact force of smaller 5 N/mm.

The invention relates to a device for producing a spun-bonded web from filaments, comprising spinnerets, a cooling chamber into which process air can be introduced in order to cool the filaments, a monomer suction device arranged between the spinnerets and the cooling chamber, a stretching unit, and a placing device for placing the filaments so as to form the spun-bonded web. The cooling chamber is divided into two cooling chamber portions. Process air can be suctioned out of a first upper cooling chamber portion to the monomer suction device with a volumetric flow rate V.sub.m, and process air exits the first upper cooling chamber portion into a second lower cooling chamber portion with a volumetric flow rate V.sub.1. The volumetric flow rate ratio V.sub.M/V.sub.1 is 0.1 to 0.3.

The invention relates to a device for producing a spun-bonded web from filaments, comprising spinnerets, a cooling chamber into which process air can be introduced in order to cool the filaments, a monomer suction device arranged between the spinnerets and the cooling chamber, a stretching unit, and a placing device for placing the filaments so as to form the spun-bonded web. The cooling chamber is divided into two cooling chamber portions. Process air can be suctioned out of a first upper cooling chamber portion to the monomer suction device with a volumetric flow rate V.sub.m, and process air exits the first upper cooling chamber portion into a second lower cooling chamber portion with a volumetric flow rate V.sub.1. The volumetric flow rate ratio V.sub.M/V.sub.1 is 0.1 to 0.3.

A spinneret, apparatus, and method are provided for making filaments for fibrous nonwoven fabrics with more uniform filament and fabric formation while minimizing filament breaks and hard spot defects in webs and fabrics made therefrom. The spinneret has a spinneret body that has an overall length to hydraulic diameter ratio and defines orifices that extend through the spinneret body, wherein the orifices comprise capillaries that open at a face of the spinneret body for polymer filament extrusion therefrom, wherein the capillaries are arranged in a plurality of different rows at the face of the spinneret body, and wherein the plurality of different rows are arranged into a plurality of different zones at the face of the spinneret body. A spinneret body of the spinneret can have an overall length to hydraulic ratio of at least 3 percent and/or a zone-to-zone length to hydraulic ratio of at least 2% and/or the hydraulic diameters, lengths, and length to hydraulic diameter ratios can progressively increase or decrease zone-to-zone for at least three different zones of capillaries, which can be applied to cross-flow quench or quench from a single-side. The spinneret body is designed to better accommodate differing operational proximity of the various different zones to quench air sources or source at commercially useful throughputs and fiber uniformity.

A spinneret, apparatus, and method are provided for making filaments for fibrous nonwoven fabrics with more uniform filament and fabric formation while minimizing filament breaks and hard spot defects in webs and fabrics made therefrom. The spinneret has a spinneret body that has an overall length to hydraulic diameter ratio and defines orifices that extend through the spinneret body, wherein the orifices comprise capillaries that open at a face of the spinneret body for polymer filament extrusion therefrom, wherein the capillaries are arranged in a plurality of different rows at the face of the spinneret body, and wherein the plurality of different rows are arranged into a plurality of different zones at the face of the spinneret body. A spinneret body of the spinneret can have an overall length to hydraulic ratio of at least 3 percent and/or a zone-to-zone length to hydraulic ratio of at least 2% and/or the hydraulic diameters, lengths, and length to hydraulic diameter ratios can progressively increase or decrease zone-to-zone for at least three different zones of capillaries, which can be applied to cross-flow quench or quench from a single-side. The spinneret body is designed to better accommodate differing operational proximity of the various different zones to quench air sources or source at commercially useful throughputs and fiber uniformity.

Provided is a method of manufacturing high strength synthetic fibers, and high strength synthetic fibers manufactured using the same. More particularly, the method involves a localized heating process by raising the temperature of a molten spinning fiber to a temperature higher than that of a pack body during a short period of time with no degradation through a heating zone located in the immediate vicinity of capillary in the spinning nozzle, so as to effectively control the molecular entanglement structure in the molten polymer without reducing the molecular weight and thus to enhance the drawability of the as-spun fibers, thereby improving the mechanical properties of the as-spun fibers, such as strength, elongation, etc., using the existing processes of melt spinning and drawing and thus enabling a mass production of a high-performance fiber at low cost.

Provided is a method of manufacturing high strength synthetic fibers, and high strength synthetic fibers manufactured using the same. More particularly, the method involves a localized heating process by raising the temperature of a molten spinning fiber to a temperature higher than that of a pack body during a short period of time with no degradation through a heating zone located in the immediate vicinity of capillary in the spinning nozzle, so as to effectively control the molecular entanglement structure in the molten polymer without reducing the molecular weight and thus to enhance the drawability of the as-spun fibers, thereby improving the mechanical properties of the as-spun fibers, such as strength, elongation, etc., using the existing processes of melt spinning and drawing and thus enabling a mass production of a high-performance fiber at low cost.

A multi-end monofilament production apparatus includes the following sequential process units along monofilaments flow direction: a vertical spinning machine comprising a spinneret and a distribution plate below the spinneret; a water bath for quenching spun monofilaments; a vacuum jet device for transferring monofilaments from the water bath; a steam jet able to provide superheated steam at a temperature within the range between 300 C. and 380 C. and at a pressure within the range between 4 bars and 5 bars; a drawing unit; and a monofilament winder for winding monofilaments at a speed exceeding 500 m/min. The present invention further proposes a method for multi-end monofilament yarn production.

A process and apparatus for producing a dimensionally stable melt blown nonwoven fibrous web. The process includes forming a multiplicity of melt blown fibers by passing a molten stream including molecules of at least one thermoplastic semi-crystalline (co)polymer through at least one orifice of a melt-blowing die, subjecting at least a portion of the melt blown fibers to a controlled in-flight heat treatment operation at a temperature below a melting temperature of the at least one thermoplastic semi-crystalline (co)polymer immediately upon exiting from the at least one orifice, and collecting at least some of the melt blown fibers subjected to the controlled in-flight heat treatment operation on a collector to form a non-woven fibrous structure. The nonwoven fibrous structure exhibits a Shrinkage less than a Shrinkage measured on an identically-prepared structure including only fibers not subjected to the controlled in-flight heat treatment operation, and generally less than 15%.

A process and apparatus for producing a dimensionally stable melt blown nonwoven fibrous web. The process includes forming a multiplicity of melt blown fibers by passing a molten stream including molecules of at least one thermoplastic semi-crystalline (co)polymer through at least one orifice of a melt-blowing die, subjecting at least a portion of the melt blown fibers to a controlled in-flight heat treatment operation at a temperature below a melting temperature of the at least one thermoplastic semi-crystalline (co)polymer immediately upon exiting from the at least one orifice, and collecting at least some of the melt blown fibers subjected to the controlled in-flight heat treatment operation on a collector to form a non-woven fibrous structure. The nonwoven fibrous structure exhibits a Shrinkage less than a Shrinkage measured on an identically-prepared structure including only fibers not subjected to the controlled in-flight heat treatment operation, and generally less than 15%.