Abstract: 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%.

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: 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: The disclosure relates to composite nonwoven fibrous web including an embedded phase having a population of particulates forming a substantially continuous three-dimensional network, and a matrix phase comprising a population of fibers forming a three-dimensional network around the particulates. The disclosure also relates to methods of making a composite nonwoven fibrous web including forming an embedded phase having a population of particulates in a substantially continuous three-dimensional network, and forming a matrix phase comprising a population of fibers forming a three-dimensional network around the particulates. Articles made from a composite nonwoven fibrous web prepared according to the methods as described above are also disclosed.

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: Fine fibers comprising aliphatic polyester and a viscosity modifier. The fine fibers are preferably made by a BMF process.

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: A melt blowing process comprising: (a) providing a thermoplastic polymer material that includes at least one or a plurality of polyester polymers and at least one or a combination of different meltable metal phosphinates; and (b) melt blowing the thermoplastic polymer material into at least one fiber or a plurality of fibers, with each fiber having a diameter or thickness that is less than about 10 microns. The metal phosphinate is in an amount that (a) reduces the viscosity of the polyester polymer and (b) functions as a crystallizing agent, which at least promotes crystallization of the polyester polymer, when the thermoplastic polymer material is melt blown into the at least one fiber. Non-woven and woven fibrous structures can be made using fibers made from this process.

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: Nonwoven fibrous webs including a multiplicity of randomly oriented discrete fibers and a multiplicity of chemically active particulates secured to the web, and methods of making and using same. In some embodiments, more than 0% and less than 10% wt. of the nonwoven fibrous web is made of multi-component fibers having at least a first region exhibiting a first melting temperature and a second region exhibiting a second melting temperature greater than the first melting temperature. In other embodiments, the discrete fibers include a first population of monocomponent thermoplastic fibers having a first melting temperature, and a second population of monocomponent fibers having a second melting temperature greater than the first melting temperature. In certain embodiments, at least some of the particulates are bonded to the fibers. In other embodiments, at least some of the particulates are secured within interstices of the fibrous web, without substantial bonding to the fibers.

Abstract: 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%.

Abstract: A melt blowing process comprising: (a) providing a thermoplastic polymer material that includes at least one or a plurality of polyester polymers and at least one or a combination of different meltable metal phosphinates; and (b) melt blowing the thermoplastic polymer material into at least one fiber or a plurality of fibers, with each fiber having a diameter or thickness that is less than about 10 microns. The metal phosphinate is in an amount that (a) reduces the viscosity of the polyester polymer and (b) functions as a crystallizing agent, which at least promotes crystallization of the polyester polymer, when the thermoplastic polymer material is melt blown into the at least one fiber. Non-woven and woven fibrous structures can be made using fibers made from this process.

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: A nozzle, die, apparatus, system and method for forming a fiber population having a median diameter less than one micrometer, and nonwoven fibrous webs including a population of such sub-micrometer fibers. The nozzle includes a first conduit having a first terminal end, a second conduit positioned coaxially around the first conduit and having a second terminal end proximate the first terminal end, wherein the first and second conduit form an annular channel between the first and second conduit, and additionally wherein the first terminal end extends axially outwardly beyond the second terminal end. The die includes at least one such nozzle, and the apparatus and system include at least one such die. Methods of making nonwoven fibrous webs including a population of sub-micrometer fibers, and articles including such nonwoven fibrous webs, 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 melt blowing process comprising: (a) providing a thermoplastic polymer material that includes at least one or a plurality of polyester polymers and at least one or a combination of different meltable metal phosphinates; and (b) melt blowing the thermoplastic polymer material into at least one fiber or a plurality of fibers, with each fiber having a diameter or thickness that is less than about 10 microns. The metal phosphinate is in an amount that (a) reduces the viscosity of the polyester polymer and (b) functions as a crystallizing agent, which at least promotes crystallization of the polyester polymer, when the thermoplastic polymer material is melt blown into the at least one fiber. Non-woven and woven fibrous structures can be made using fibers made from this process.

Abstract: The disclosure relates to composite nonwoven fibrous webs including a population of sub-micrometer fibers having a median diameter less than one micrometer (?m), and a population of microfibers having a median diameter of at least 1 ?m. At least, one of the fiber populations is oriented, and each composite nonwoven fibrous web has a thickness and exhibits a Solidity of less than 10%. The disclosure also relates to methods of making composite nonwoven fibrous webs, and articles including composite nonwoven fibrous webs made according to the methods. In exemplary applications, the articles may be used as gas filtration articles, liquid filtration articles, sound absorption articles, surface cleaning articles, cellular growth support articles, drug delivery articles, personal hygiene articles, or wound dressing articles.

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.