Spunbond nonwoven fabric

A spunbond nonwoven fabric comprising a multiplicity of substantially continuous bicomponent polyester filaments randomly arranged and bonded to one another, said bicomponent polyester filaments having a multilobal cross-sectional configuration including a first polymer component formed of a polyethylene terephthalate homopolymer occupying at least the central portion of the filament cross-section and a second polymer component formed of polyethylene isophthalate copolymer present at the tip of at least one lobe of the multilobal cross-section.

A spunbond polyester nonwoven fabric formed by a multiplicity of randomly arranged substantially continuous bicomponent polyester filaments, the bicomponent filaments having a trilobal cross-section including a first polymer component formed of polyethylene terephthalate homopolymer occupying at least the central portion of the trilobal cross-section and a second polymer component formed of a copolymer of polyethylene isophthalate and polyethylene terephthalate occupying the tip portion of at least one of the lobes of the trilobal cross-section, and a multiplicity of fusion bonds formed by said second polymer component bonding with other filaments of the fabric at filament cross over points, said fusion bonds being located uniformly throughout the area of the fabric, and wherein the ratio of the web tensile strength to web tear strength in the same web direction is 3 or greater.

A method of making a spunbond nonwoven fabric comprising melt extruding a multiplicity of substantially continuous bicomponent filaments having a multilobal cross-sectional configuration including a first polymer component formed of a higher-melting composition occupying at least the central portion of the filament cross-section and a second polymer component formed of a lower-melting composition being present in at least one lobe of the multilobal cross-section, depositing the filaments on a collection surface to form a web, and bonding the filaments to form a bonded nonwoven web.

A method of making a spunbonded nonwoven fabric comprising separately melting a first polymer component formed of a polyethylene terephthalate homopolymer and a second polymer component formed of polyethylene isophthalate copolymer, directing the first and second polymer components through spinneret orifices configured to form a multilobal cross-section filaments in which the first polymer component occupies at least the central portion of the filament cross-section and the second polymer component is present at the tip of at least one lobe of the multilobal cross-section, randomly depositing the filaments on an advancing collection surface to form a web, directing the web of randomly deposited filaments through a heated zone and heating the filaments to a temperature at which the lower-melting second polymer composition softens and becomes adhesive while the first polymer component remains solid, so that the softened second polymer component adheres to portions of other filaments at filament crossover points, and cooling the filaments to solidify the second polymer composition and form a bonded nonwoven web.