Abstract: The present invention provides a process for producing yarn having reduced heatset shrinkage. Preferably, the fibers used in making the yarn are bicomponent fibers. The present invention also provides a process for producing yarn having reduced heatset shrinkage at reduced heat temperatures.

Abstract: An ozone fade resistant dyed carpet made of dyed sheath/core face fibers has a sheath substantially or completely covering the core. The sheath is composed of a fiber-forming polymer which is inherently chemically compatible and is selected from polymers that are resistant to dye migration and yet inherently chemically compatible with the core polymer. The face fibers are dyed with at least one acid dye, basic dye or disperse dye and resist ozone fading as indicated by a CIEL*a*b* total color difference from the original unexposed sample after at least 3 cycles of ozone fading that is less than one-half of the CIEL*a*b* total color difference seen for a fiber composed substantially completely of said core polyamide component that is dyed with the same dyes. The fibers may be cabled and heatset in which case even more substantial improvement in the ozone fastness is observed.

Abstract: Continuous anionic polymerization and melt-spinning of a polycaprolactam includes forming a reaction mixture by bringing at least two streams of liquid caprolactam respectively containing a polymerization initiator and co-initiator into contact with one another, and then subjecting the reaction mixture to anionic polymerization reaction conditions in the reactor zone to obtain a molten polycaprolactam. The molten polycaprolactam is the directly (i.e., without intermediate solidification) transferred to, and extruded through, a fiber-forming orifice of a spinneret to form a fiber thereof. A spinneret zone downstream of the reactor zone thus receives the molten polycaprolactam directly from the reactor zone and forms a fiber therefrom by extruding it through the spinneret's fiber-spinning orifice.

Abstract: An ozone fade resistant dyed carpet made of dyed sheath/core face fibers has a sheath substantially or completely covering the core. The sheath is composed of a fiber-forming polymer which is inherently chemically compatible and is selected from polymers that are resistant to dye migration and yet inherently chemically compatible with the core polymer. The face fibers are dyed with at least one acid dye, basic dye or disperse dye and resist ozone fading as indicated by a CIEL*a*b* total color difference from the original unexposed sample after at least 3 cycles of ozone fading that is less than one-half of the CIEL*a*b* total color difference seen for a fiber composed substantially completely of said core polyamide component that is dyed with the same dyes. The fibers may be cabled and heatset in which case even more substantial improvement in the ozone fastness is observed.

Abstract: The present invention provides a process for producing yarn having reduced heatset shrinkage. Preferably, the fibers used in making the yarn are bicomponent fibers. The present invention also provides a process for producing yarn having reduced heatset shrinkage at reduced heat temperatures.

Abstract: Dyeable and dyed filaments have a core and a sheath which entirely surrounds the core. The core is formed of a core polymer which is susceptible to dyeing by a dye bath chemical, while the sheath is formed of a sheath polymer which is resistant to dyeing by the dye bath chemical. When the filament is brought into contact with a dye bath containing the dye chemical, the dye chemical in the dye bath will physically diffuse or migrate through the sheath polymer to cause the core polymer to be dyed a color of the dye bath chemical, while the sheath polymer is substantially undyed thereby.

Abstract: The present invention provides a process for producing yarn having reduced heatset shrinkage. Preferably, the fibers used in making the yarn are bicomponent fibers. The present invention also provides a process for producing yarn having reduced heatset shrinkage at reduced heat temperatures.

Abstract: Continuous anionic polymerization and melt-spinning of a polycaprolactam includes forming a reaction mixture by bringing at least two streams of liquid caprolactam respectively containing a polymerization initiator and co-initiator into contact with one another, and then subjecting the reaction mixture to anionic polymerization reaction conditions to obtain a molten polycaprolactam. The molten polycaprolactam is the directly (i.e., without intermediate solidification) transferred to, and extruded through, a fiber-forming orifice of a spinneret to form a fiber thereof. One exemplary system to achieve such continuous anionic polymerization and melt-spinning of polycaprolactam includes a mixer for receiving and mixing at least two streams of liquid caprolactam respectively containing a polymerization initiator and co-initiator, and a reactor and melt-spinning apparatus downstream of the mixer.

Abstract: Continuous anionic polymerization and melt-spinning of a polycaprolactam includes forming a reaction mixture by bringing at least two streams of liquid caprolactam respectively containing a polymerization initiator and co-initiator into contact with one another, and then subjecting the reaction mixture to anionic polymerization reaction conditions to obtain a molten polycaprolactam. The molten polycaprolactam is the directly (i.e., without intermediate solidification) transferred to, and extruded through, a fiber-forming orifice of a spinneret to form a fiber thereof. One exemplary system to achieve such continuous anionic polymerization and melt-spinning of polycaprolactam includes a mixer for receiving and mixing at least two streams of liquid caprolactam respectively containing a polymerization initiator and co-initiator, and a reactor and melt-spinning apparatus downstream of the mixer.

Abstract: Dyeable and dyed filaments have a core and a sheath which entirely surrounds the core. The core is formed of a core polymer which is susceptible to dyeing by a dye bath chemical, while the sheath is formed of a sheath polymer which is resistant to dyeing by the dye bath chemical. When the filament is brought into contact with a dye bath containing the dye chemical, the dye chemical in the dye bath will physically diffuse or migrate through the sheath polymer to cause the core polymer to be dyed a color of the dye bath chemical, while the sheath polymer is substantially undyed thereby.

Abstract: Dyeable and dyed filaments have a core and a sheath which entirely surrounds the core. The core is formed of a core polymer which is susceptible to dyeing by a dye bath chemical, while the sheath is formed of a sheath polymer which is resistant to dyeing by the dye bath chemical. When the filament is brought into contact with a dye bath containing the dye chemical, the dye chemical in the dye bath will physically diffuse or migrate through the sheath polymer to cause the core polymer to be dyed a color of the dye bath chemical, while the sheath polymer is substantially undyed thereby.

Abstract: Continuous anionic polymerization and melt-spinning of a polycaprolactam includes forming a reaction mixture by bringing at least two streams of liquid caprolactam respectively containing a polymerization initiator and co-initiator into contact with one another, and then subjecting the reaction mixture to anionic polymerization reaction conditions to obtain a molten polycaprolactam. The molten polycaprolactam is the directly (i.e., without intermediate solidification) transferred to, and extruded through, a fiber-forming orifice of a spinneret to form a fiber thereof. One exemplary system to achieve such continuous anionic polymerization and melt-spinning of polycaprolactam includes a mixer for receiving and mixing at least two streams of liquid caprolactam respectively containing a polymerization initiator and co-initiator, and a reactor and melt-spinning apparatus downstream of the mixer.

Abstract: Continuous anionic polymerization and melt-spinning of a polycaprolactam includes forming a reaction mixture by bringing at least two streams of liquid caprolactam respectively containing a polymerization initiator and co-initiator into contact with one another, and then subjecting the reaction mixture to anionic polymerization reaction conditions to obtain a molten polycaprolactam. The molten polycaprolactam is the directly (i.e., without intermediate solidification) transferred to, and extruded through, a fiber-forming orifice of a spinneret to form a fiber thereof. One exemplary system to achieve such continuous anionic polymerization and melt-spinning of polycaprolactam includes a mixer for receiving and mixing at least two streams of liquid caprolactam respectively containing a polymerization initiator and co-initiator, and a reactor and melt-spinning apparatus downstream of the mixer.

Abstract: Superconductor containing filaments having embedments of superconducting material surrounded by a rayon matrix are formed by preparing a liquid suspension which contains at least 10 weight percent superconducting material; forming a multicomponent filament having a core of the suspension and a viscose sheath which contains cellulose xanthate; and thereafter, regenerating cellulose from the cellulose xanthate to form a rayon matrix.

Abstract: The present invention provides a process for producing yarn having reduced heatset shrinkage. Preferably, the fibers used in making the yarn are bicomponent fibers. The present invention also provides a process for producing yarn having reduced heatset shrinkage at reduced heat temperatures.

Abstract: Dyeable and dyed filaments have a core and a sheath which entirely surrounds the core. The core is formed of a core polymer which is susceptible to dyeing by a dye bath chemical, while the sheath is formed of a sheath polymer which is resistant to dyeing by the dye bath chemical. When the filament is brought into contact with a dye bath containing the dye chemical, the dye chemical in the dye bath will physically diffuse or migrate through the sheath polymer to cause the core polymer to be dyed a color of the dye bath chemical, while the sheath polymer is substantially undyed thereby.

Abstract: An acid-dye and coffee stain resistant carpet has sheath/core bicomponent face fibers affixed in a backing material and bound thereto. The face fibers have a core of a first polyamide component and a sheath which substantially or completely covers the core of a second polyamide component which is inherently chemically compatible with the first polyamide component. In an uncolored state, the carpet has a red drink staining depth of less than 15 CIE &Dgr;E units and a coffee staining depth of less than about 10 CIE &Dgr;E units.

Abstract: An ozone fade resistant dyed carpet made of dyed sheath/core face fibers has a sheath substantially or completely covering the core. The sheath is composed of a fiber-forming polymer which is inherently chemically compatible and is selected from polymers that are resistant to dye migration and yet inherently chemically compatible with the core polymer. The face fibers are dyed with at least one acid dye, basic dye or disperse dye and resist ozone fading as indicated by a CIEL*a*b* total color difference from the original unexposed sample after at least 3 cycles of ozone fading that is less than one-half of the CIEL*a*b* total color difference seen for a fiber composed substantially completely of said core polyamide component that is dyed with the same dyes. The fibers may be cabled and heatset in which case even more substantial improvement in the ozone fastness is observed.

Abstract: Relatively thin (e.g., thickness of less than about 2.5 mm, and typically no greater than about 1.0 mm) plates for synthetic fiber-forming spin packs include a first metal layer exhibiting a relatively slow photochemical etching property and a second metal layer exhibiting a relatively fast photochemical etching property which are adhered (laminated) to one another to form a composite substrate structure. The differential etch rates as between the first and second metal layers permit relatively dimensionally larger distribution channels and relatively dimensionally precise through holes to be formed in the composite substrate. In this regard, the second metal layer permits the formation via photochemical etching of dimensionally deeper and/or wider polymer distribution channels. The first metal layer, on the other hand, allows for the formation of relatively dimensionally precise through holes via concurrent (simultaneous) etching with the second metal layer.

Abstract: Multicomponent fibers and methods of producing the same are provided such that an inter-domain boundary layer is interposed between distinct domains formed of incompatible polymers so as to minimize (if not eliminate entirely) separation of the domains at their interfacial boundary. The polymer forming the inter-domain boundary layer therefore is provided so as to be compatible with the otherwise incompatible polymers forming each of the domains between which it is interposed.