摘要:
Shaped filtration articles are made from a monocomponent nonwoven web formed by flowing first and second fiber-forming materials of the same polymeric composition through first and second die cavities in respective fluid communication with first and second sets of orifices in a meltblowing die tip. The first fiber-forming material flows at a lesser flow rate or viscosity through the first die cavity and first set of orifices to form a set of smaller size filaments and the second fiber-forming material flows at a greater flow rate or viscosity through the second die cavity and second set of orifices to form a set of larger size filaments. The collected nonwoven web contains a meltblown bimodal mass fraction/fiber size mixture of intermingled continuous microfibers and larger size fibers of the same polymeric composition.
摘要:
Shaped filtration articles are made from a monocomponent nonwoven web formed by flowing first and second fiber-forming materials of the same polymeric composition through first and second die cavities in respective fluid communication with first and second sets of orifices in a meltblowing die tip. The first fiber-forming material flows at a lesser flow rate or viscosity through the first die cavity and first set of orifices to form a set of smaller size filaments and the second fiber-forming material flows at a greater flow rate or viscosity through the second die cavity and second set of orifices to form a set of larger size filaments. The collected nonwoven web contains a meltblown bimodal mass fraction/fiber size mixture of intermingled continuous microfibers and larger size fibers of the same polymeric composition.
摘要:
A porous monocomponent nonwoven web contains a bimodal mass fraction/fiber size mixture of intermingled continuous microfibers and larger size fibers of the same polymeric composition. There are at least five times as many microfibers as larger size fibers, and a histogram of the mass fraction of fibers vs. fiber size exhibits a larger size fiber mode greater than 10 μm. The web may be made by flowing fiber-forming material through a die cavity having larger size orifices and at least five times as many smaller size orifices to form filaments, attenuating the filaments into fibers and collecting the attenuated fibers to form the nonwoven web. The web is especially well suited to the manufacture of self-supporting three dimensional articles such as molded cup-shaped respirators and pleated air filters.
摘要:
A porous monocomponent nonwoven web contains a bimodal mass fraction/fiber size mixture of intermingled continuous microfibers and larger size fibers of the same polymeric composition. There are at least five times as many microfibers as larger size fibers, and a histogram of the mass fraction of fibers vs. fiber size exhibits a larger size fiber mode greater than 10 μm. The web may be made by flowing fiber-forming material through a die cavity having larger size orifices and at least five times as many smaller size orifices to form filaments, attenuating the filaments into fibers and collecting the attenuated fibers to form the nonwoven web. The web is especially well suited to the manufacture of self-supporting three dimensional articles such as molded cup-shaped respirators and pleated air filters.
摘要:
A molded respirator is made from a monocomponent monolayer nonwoven web containing a bimodal mass fraction/fiber size mixture of intermingled continuous monocomponent polymeric microfibers and larger size fibers of the same polymeric composition. The respirator is a cup-shaped porous monocomponent monolayer matrix whose matrix fibers are bonded to one another at at least some points of fiber intersection. The matrix has a King Stiffness greater than 1 N. The respirator may be formed without requiring stiffening layers, bicomponent fibers, or other reinforcement in the filter media layer.
摘要:
A pleated filter is made from a monocomponent monolayer nonwoven web containing a bimodal mass fraction/fiber size mixture of intermingled larger size and smaller size continuous monocomponent polymeric fibers of the same polymeric composition. Rows of pleats are formed in the nonwoven web, and the pleated web is cut to a desired size and shape to provide a filter element containing a self-supporting porous monocomponent monolayer matrix of fibers bonded to one another at at least some points of fiber intersection and having an average initial submicron efficiency of at least 15% at a 1.52 meters/sec face velocity. The filter element is deformation resistant without requiring stiffening layers, bicomponent fibers or other reinforcing measures in the filter media layer.
摘要:
A molded respirator is made from a monocomponent monolayer nonwoven web containing a bimodal mass fraction/fiber size mixture of intermingled continuous monocomponent polymeric microfibers and larger size fibers of the same polymeric composition. The respirator is a cup-shaped porous monocomponent monolayer matrix whose matrix fibers are bonded to one another at least some points of fiber intersection. The matrix has a King Stiffness greater than 1 N. The respirator may be formed without requiring stiffening layers, bicomponent fibers, or other reinforcement in the filter media layer.
摘要:
A molded respirator is made from a monocomponent monolayer nonwoven web containing a bimodal mass fraction/fiber size mixture of intermingled continuous monocomponent polymeric microfibers and larger size fibers of the same polymeric composition. The respirator is a cup-shaped porous monocomponent monolayer matrix whose matrix fibers are bonded to one another at at least some points of fiber intersection. The matrix has a King Stiffness greater than 1 N. The respirator may be formed without requiring stiffening layers, bicomponent fibers, or other reinforcement in the filter media layer.
摘要:
A pleated filter is made from a monocomponent monolayer nonwoven web containing a bimodal mass fraction/fiber size mixture of intermingled larger size and smaller size continuous monocomponent polymeric fibers of the same polymeric composition. Rows of pleats are formed in the nonwoven web, and the pleated web is cut to a desired size and shape to provide a filter element containing a self-supporting porous monocomponent monolayer matrix of fibers bonded to one another at at least some points of fiber intersection and having an average initial submicron efficiency of at least 15% at a 1.52 meters/sec face velocity. The filter element is deformation resistant without requiring stiffening layers, bicomponent fibers or other reinforcing measures in the filter media layer.
摘要:
A porous monocomponent nonwoven web contains a bimodal mass fraction/fiber size mixture of intermingled continuous microfibers and larger size fibers of the same polymeric composition. There are at least five times as many microfibers as larger size fibers, and a histogram of the mass fraction of fibers vs. fiber size exhibits a larger size fiber mode greater than 10 μm. The web may be made by flowing fiber-forming material through a die cavity having larger size orifices and at least five times as many smaller size orifices to form filaments, attenuating the filaments into fibers and collecting the attenuated fibers to form the nonwoven web. The web is especially well suited to the manufacture of self-supporting three dimensional articles such as molded cup-shaped respirators and pleated air filters.