The present invention relates to a flame-retardant nonwoven fabric for a mattress, and a flame-retardant nonwoven fabric for mattresses comprising flame-retardant rayon (FR-Rayon) staple fibers of 20 to 50% by weight; modacrylic staple fibers of 30 to 60% by weight; polyimide (PI) staple fibers of 10 to 30% by weight; and low melting polyester (LM PET) staple fibers of 5 to 20% by weight provides enhanced flame retarding and mechanical properties.

Charged polymeric webs, such as electret webs, include a thermoplastic resin and a charge-enhancing additive. The additives are substituted heterocyclic thiolate salts. The heterocyclic thiolate salt has 2 nitrogen groups and a third group that may be an NH, N—NH.sub.2, O, or S group. The substituent group is an aromatic or heterocyclic aromatic group. The electret webs may be a non-woven fibrous web or a film. The electret webs are suitable for use as filter media.

A waterproof and moisture-permeable composite material is provided, which is composed of a waterproof and moisture-permeable membrane and a melt-blown non-woven fabric. The melting point of melt-blown non-woven fabric ranges from 80° C. to 130° C., in which the melt-blown non-woven fabric is a thermoplastic polymer which may be a thermoplastic polyether ester elastomer polymer. A method for forming a waterproof and moisture-permeable composite material includes: providing a thermoplastic polymer; performing a melt-blown process to the thermoplastic polymer by using an extruder to form a melt-blown fiber, so the melt-blown fiber on a conveyer belt with multiple meshes to form a melt-blown non-woven fabric; covering a moisture-permeable membrane on the melt-blown non-woven fabric to adhere the moisture-permeable membrane and the melt-blown non-woven fabric to form a waterproof and moisture-permeable composite material.

Charged polymeric webs, such as electret webs, include a thermoplastic resin and a charge-enhancing additive. The additives are substituted heterocyclic thiols. The heterocyclic thiol has 2 nitrogen groups and a third group that may be an NH, N-NH.sub.2, O, or S group. The substituent group is an aromatic or heterocyclic aromatic group. The electret webs may be a non-woven fibrous web or a film. The electret webs are suitable for use as filter media.

Use of an electrically charged nonwoven fabric that is made of a fiber predominantly composed of an amorphous polymer provides a novel filtration material having improved performance compared to that of conventional filtration materials, and having excellent heat resistance and excellent flame retardancy as well as an electrically charged nonwoven fabric for use in the filtration material. It is preferable that the surface charge density is greater than or equal to 1×10.sup.−10 coulomb/cm.sup.2. It is preferable that the collection efficiency for collecting a dust particle with a particle diameter of 1 μm flowing at a fabric-passing velocity of 8.6 cm/second is greater than or equal to 40%, the QF value is greater than or equal to 0.05, and the decrement of the dust-particle collection efficiency after being allowed to leave at 100° C. for 24 hours is less than or equal to 10%.

The present invention provides a polyimide solution which does not require a ring-closing process at a high temperature for obtaining a heat-resistant polyimide non-woven fabric and which is hardly affected by atmosphere humidity in fiber production by electrospinning, so that a fiber with a stable diameter can be obtained in any circumstance.

A polyimide solution including: (a) a resin containing 50 mol % or more, based on the total amount of the resin, of a structural unit represented by the general formula (1); and (b) a solvent.

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The present invention provides a polyimide solution which does not require a ring-closing process at a high temperature for obtaining a heat-resistant polyimide non-woven fabric and which is hardly affected by atmosphere humidity in fiber production by electrospinning, so that a fiber with a stable diameter can be obtained in any circumstance.

A polyimide solution including: (a) a resin containing 50 mol % or more, based on the total amount of the resin, of a structural unit represented by the general formula (1); and (b) a solvent.

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Provided is a blood filter that resists deterioration in properties as a result of electron beam sterilization treatment performed before or during use as a blood filter, has durability, dimensional stability, and chemical resistance at excellent levels, also has biocompatibility, and resists deterioration in properties even upon the electron beam sterilization treatment. The blood filter according to the present invention includes a nonwoven fabric made of PEEK fibers. Preferably, the blood filter according to the present invention has an average pore size of 3 to 280 μm and has a porosity of 15% to 70%; and the PEEK fibers have an average fiber diameter of 10 μm or less.

A nonwoven for use in a thermal liner for protective apparel includes 1-45 wt % of a first inherently heat resistant fiber excluding an aramid, and a balance of a second heat resistant fiber. The nonwoven excludes wool and has a thickness less than 3 mm and a basis weight of less than 2.9 osy (100 gsm). In another embodiment, the insulating layer for protective apparel includes a nonwoven including an inherently flame resistant fiber and fibers being inherently resistant to moisture absorption. The inherently flame resistant fiber is different from said inherently resistant to moisture absorption fiber. The nonwoven has an equivalent or better thermal protective performance (TPP) and a lower basis weight than an industry standard nonwoven consisting of a nonwoven of para-aramids or meta-aramids or a blend of both.

This invention relates to a method of manufacturing a superabsorbent polymer fiber and a superabsorbent polymer fiber manufactured thereby.