Abstract: A single-layer spunbonded air-filtration web including meltspun autogenously bonded electret fibers with an Actual Fiber Diameter of from 3.0 microns to 15 microns. The air-filtration web exhibits a ratio of mean flow pore size to pore size range of from 0.55 to 2.5. Also disclosed are methods of making such webs, and methods of using such webs to perform air filtration.

Abstract: A single-layer spunbonded air-filtration web including meltspun autogenously bonded electret fibers with an Actual Fiber Diameter of from 3.0 microns to 9.0 microns. The air-filtration web exhibits a mean flow pore size of from 8.0 to 19 microns and exhibits a ratio of mean flow pore size to pore size range of from 0.55 to 2.5. Also disclosed are methods of making such webs, and methods of using such webs to perform air filtration.

Abstract: The present disclosure relates to multi-layer composite articles including at least two nonwoven web layers. Each or the layers may be a spunbonded web, and each may include biodegradable materials. The multi-layered composites of the present disclosure are particularly well suited for air filtration, as they can combine a high dust holding capacity with sufficient strength, dimensional stability, and a relatively low pressure drop.

Abstract: Nonwoven webs including one or more semi-continuous filaments made of a mixture including from about 50% w/w to about 99% w/w of at least one crystalline polyolefin (co)polymer, and from about 1% w/w to about 40% w/w of at least one hydrocarbon tackifier resin. The at least one semi-continuous filament exhibits molecular orientation, and at least one of the crystalline polyolefin (co)polymer or the nonwoven web exhibits a Heat of Fusion measured using Differential Scanning Calorimetry of greater than 50 Joules/g. A process for making the semi-continuous filaments and nonwoven webs is also disclosed.

Abstract: A flat-fold respirator is made from a stiff filtration panel joined to the remainder of the respirator through at least one line of demarcation. The panel contains a porous monocomponent monolayer nonwoven web that contains charged intermingled continuous monocomponent polymeric fibers of the same polymeric composition and that has sufficient basis weight or inter-fiber bonding so that the web exhibits a Gurley Stiffness greater than 200 mg and the respirator exhibits less than 20 mm H2O pressure drop. The respirator may be formed without requiring additional stiffening layers, bicomponent fibers, or other reinforcement and can be flat-folded for storage. Scrap from the manufacturing process may be recycled to make additional stiff filtration panel web.

Abstract: A web of nonwoven fabric suitable for, e.g., the loop portion of a hook-and-loop fastening system. The method for making this material relies on differential shrinkage of different layers to cause the loops to self-form. The method is robust and simpler than that previously used for similar constructions.

Abstract: Spunbonded electret webs comprising polylactic acid fibers, in which at least some of the polylactic acid fibers are meltspun, drawn, charged fibers that include charging additive; and, methods of making such fibers and webs.

Abstract: A flat-fold respirator is made from a stiff filtration panel joined to the remainder of the respirator through at least one line of demarcation. The panel contains a porous monocomponent monolayer nonwoven web that contains charged intermingled continuous monocomponent polymeric fibers of the same polymeric composition and that has sufficient basis weight or inter-fiber bonding so that the web exhibits a Gurley Stiffness greater than 200 mg and the respirator exhibits less than 20 mm H2O pressure drop. The respirator may be formed without requiring additional stiffening layers, bicomponent fibers, or other reinforcement and can be flat-folded for storage. Scrap from the manufacturing process may be recycled to make additional stiff filtration panel web.

Abstract: A flat-fold respirator is made from a stiff filtration panel joined to the remainder of the respirator through at least one line of demarcation. The panel contains a porous monocomponent monolayer nonwoven web that contains charged intermingled continuous monocomponent polymeric fibers of the same polymeric composition and that has sufficient basis weight or inter-fiber bonding so that the web exhibits a Gurley Stiffness greater than 200 mg and the respirator exhibits less than 20 mm H2O pressure drop. The respirator may be formed without requiring additional stiffening layers, bicomponent fibers, or other reinforcement and can be flat-folded for storage. Scrap from the manufacturing process may be recycled to make additional stiff filtration panel web.

Abstract: Spunbonded electret webs comprising polylactic acid fibers, in which at least some of the polylactic acid fibers are meltspun, drawn, charged fibers that include charging additive; and, methods of making such fibers and webs.

Abstract: Dimensionally stable nonwoven fibrous webs include a plurality of fibers formed from one or more thermoplastic polyesters and an antishrink additive, preferably in an amount greater than 0% and no more than 10% by weight of the web. The webs have at least one dimension which decreases by no greater than 12% in the plane of the web when heated to a temperature above a glass transition temperature of the fibers. The webs may be used as wipes.

Abstract: Dimensionally stable nonwoven fibrous webs include a multiplicity of continuous fibers formed from one or more thermoplastic polyesters and polypropylene in an amount greater than 0% and no more than 10% by weight of the web. The webs have at least one dimension which decreases by no greater than 10% in the plane of the web when heated to a temperature above a glass transition temperature of the fibers. When the thermoplastic polyester is selected to include aliphatic and aromatic polyesters, a spunbond process may be used to produce substantially continuous fibers that exhibit molecular orientation. When the thermoplastic polyester is selected from aliphatic polyesters, a meltblown process may be used to produce discontinuous fibers that do not exhibit molecular orientation. The webs may be used as articles for filtration, sound absorption, thermal insulation, surface cleaning, cellular growth support, drug delivery, personal hygiene, medical apparel, or wound dressing.

Abstract: Dimensionally stable nonwoven fibrous webs include a multiplicity of continuous fibers formed from one or more thermoplastic polyesters and polypropylene in an amount greater than 0% and no more than 10% by weight of the web. The webs have at least one dimension which decreases by no greater than 10% in the plane of the web when heated to a temperature above a glass transition temperature of the fibers. When the thermoplastic polyester is selected to include aliphatic and aromatic polyesters, a spunbond process may be used to produce substantially continuous fibers that exhibit molecular orientation. When the thermoplastic polyester is selected from aliphatic polyesters, a meltblown process may be used to produce discontinuous fibers that do not exhibit molecular orientation. The webs may be used as articles for filtration, sound absorption, thermal insulation, surface cleaning, cellular growth support, drug delivery, personal hygiene, medical apparel, or wound dressing.

Abstract: Dimensionally stable nonwoven fibrous webs include a multiplicity of continuous fibers formed from one or more thermoplastic polyesters and polypropylene in an amount greater than 0% and no more than 10% by weight of the web. The webs have at least one dimension which decreases by no greater than 10% in the plane of the web when heated to a temperature above a glass transition temperature of the fibers. A spunbond process may be used to produce substantially continuous fibers that exhibit molecular orientation. A meltblown process may be used to produce discontinuous fibers that do not exhibit molecular orientation. In some embodiments, the fibers comprise a viscosity modifier and/or an anionic surfactant. The webs may be used as articles for filtration, sound absorption, thermal insulation, surface cleaning, cellular growth support, drug delivery, personal hygiene, medical apparel, or wound dressing.

Abstract: High loft nonwoven webs including a population of substantially continuous mono-component melt-spun filaments, wherein the nonwoven web exhibits a Solidity of less than eight percent with a weight normalized cross direction (CD) tensile greater than 10 Newtons per 100 grams per square meter of web weight (10 N/100 gsm), and wherein the nonwoven web is substantially free of gap-formed fibers, crimped fibers, staple fibers, and bi-component fibers. High loft spun-bond nonwoven webs can be advantageously used in filtration articles. Methods of making high loft spun-bond nonwoven webs, and filtration articles including high loft spun-bond webs made according to the methods, are also disclosed.

Abstract: Dimensionally stable nonwoven fibrous webs include a multiplicity of continuous fibers formed from one or more thermoplastic polyesters and polypropylene in an amount greater than 0% and no more than 10% by weight of the web. The webs have at least one dimension which decreases by no greater than 10% in the plane of the web when heated to a temperature above a glass transition temperature of the fibers. A spunbond process may be used to produce substantially continuous fibers that exhibit molecular orientation. A meltblown process may be used to produce discontinuous fibers that do not exhibit molecular orientation. The webs may be used as articles for filtration, sound absorption, thermal insulation, surface cleaning, cellular growth support, drug delivery, personal hygiene, medical apparel, or wound dressing.

Abstract: A method for making a bonded nonwoven fibrous web comprising 1) providing a nonwoven fibrous web that comprises oriented semicrystalline polymeric fibers, and 2) subjecting the web to a controlled heating and quenching operation that includes a) forcefully passing through the web a fluid heated to at least the onset melting temperature of said polymeric material for a time too short to wholly melt the fibers, and b) immediately quenching the web by forcefully passing through the web a fluid at a temperature at least 50° C. less than the Nominal Melting Point of the material of the fibers. The fibers of the treated web generally have i) an amorphous-characterized phase that exhibits repeatable softening (making the fibers softenable) and ii) a crystallite-characterized phase that reinforces the fiber structure during softening of the amorphous-characterized phase, whereby the fibers may be autogenously bonded while retaining orientation and fiber structure.

Abstract: A method for making a bonded nonwoven fibrous web comprising extruding melt blown fibers of a polymeric material, collecting the melt blown fibers as an initial nonwoven fibrous web, annealing the initial nonwoven fibrous web with a controlled heating and cooling operation, and collecting the dimensionally stable bonded nonwoven fibrous web is described. The bonded nonwoven fibrous web shrinkage is typically less than 4 percent relative to the initial nonwoven fibrous web.

Abstract: Dimensionally stable nonwoven fibrous webs include a multiplicity of continuous fibers formed from one or more thermoplastic polyesters and polypropylene in an amount greater than 0% and no more than 10% by weight of the web. The webs have at least one dimension which decreases by no greater than 10% in the plane of the web when heated to a temperature above a glass transition temperature of the fibers. A spunbond process may be used to produce substantially continuous fibers that exhibit molecular orientation. A meltblown process may be used to produce discontinuous fibers that do not exhibit molecular orientation. In some embodiments, the fibers comprise a viscosity modifier and/or an anionic surfactant. The webs may be used as articles for filtration, sound absorption, thermal insulation, surface cleaning, cellular growth support, drug delivery, personal hygiene, medical apparel, or wound dressing.

Abstract: Dimensionally stable nonwoven fibrous webs include a multiplicity of continuous fibers formed from one or more thermoplastic polyesters and polypropylene in an amount greater than 0% and no more than 10% by weight of the web. The webs have at least one dimension which decreases by no greater than 10% in the plane of the web when heated to a temperature above a glass transition temperature of the fibers. A spunbond process may be used to produce substantially continuous fibers that exhibit molecular orientation. A meltblown process may be used to produce discontinuous fibers that do not exhibit molecular orientation. In some embodiments, the fibers comprise a viscosity modifier and/or an anionic surfactant. The webs may be used as articles for filtration, sound absorption, thermal insulation, surface cleaning, cellular growth support, drug delivery, personal hygiene, medical apparel, or wound dressing.