A polylactic acid nano-fiber membrane and preparation method thereof. In particular, the membrane has PLA nanofibers with an average diameter between 50 nm and 200 nm, wherein the nanofibers contain a crystal phase with a volume fraction between 45% and 85% and the crystal phase contains PLA stereocomplex crystals with a volume fraction between 85% and 95%. The method of preparation includes mixing dried PDLA and PLLA in a specific PLLA/PDLA ratio of between 95/5 and 99/1; producing continuous fibers or nonwovens in a extrusion and spinning device, and producing woven fabrics or nonwovens with the continuous fibers; heat treating the woven fabrics or nonwovens; washing the heat treated woven fabrics or nonwovens with a solvent; removing the solvent and drying the woven fabrics or nonwovens; and pressing the dried woven fabrics or nonwovens for making the membrane.

Disclosed are improved polymer materials. Also disclosed are fine fiber materials that can be made from the improved polymeric materials in the form of microfiber and nanofiber structures. The microfiber and nanofiber structures can be used in a variety of useful applications including the formation of filter materials.

A textile applicator for application of a sanitizing and/or disinfecting solution to a surface. The applicator incorporates a plurality of direct spun polyester microfiber yarns to define a textile surface which does not bind or inactivate quaternary ammonium compounds, chlorine-based or peracetic and/or other peroxygen based sanitizing and/or disinfecting agents. Thus, the sanitizing and/or disinfecting agent is readily released to the surface being treated without any requirement of pre-loading surface binding sites or applying a charge-modifying surface treatment.

A hygiene article including a nonwoven web having nanofibers. The hygiene articles include diapers, training pants, adult incontinence pads, catamenials products, tampons, personal cleansing articles, and personal care articles. The nanofiber webs can be used as a barrier, wipe, or absorbent material. Particularly, the nanofiber web is used in a diaper as a barrier-on-core, outercover, and/or leg cuff. It may also be used as a wipe.

A textile applicator for application of a sanitizing and/or disinfecting solution to a surface. The applicator incorporates a plurality of direct spun polyester microfiber yarns to define a textile surface which does not bind or inactivate quaternary ammonium compounds, chlorine-based or peracetic and/or other peroxygen based sanitizing and/or disinfecting agents. Thus, the sanitizing and/or disinfecting agent is readily released to the surface being treated without any requirement of pre-loading surface binding sites or applying a charge-modifying surface treatment.

The invention provides a nonwoven electret web comprising fibers made from a thermoplastic polymer material which comprises a polymer, a first additive (a) and a second additive (b), wherein the first additive (a) comprises a hindered amine and the second additive (b) comprises a metal salt of a carboxylic acid and/or an organic amide derived from a carboxylic acid and an amine. The invention further provides a process for making the nonwoven electret web, a fiber, a process for making the fiber, a multi-layer sheet, and the use of the nonwoven electret web, the fiber or the multilayered sheet as a filter material or as a dust-removing fabric for cleaning purposes.

A nonwoven substrate comprising a polyolefin and an engineering thermoplastic polymer. The engineering thermoplastic polymer may be present in the nonwoven substrate at a level of between about 1% and about 20% by weight of the nonwoven substrate. The layer of fibers is free of a compatibilizer.

A liquid-retaining sheet contains a liquid-retaining layer that is able to absorb a liquid component, and the liquid-retaining layer is formed from a nonwoven structural member containing a transparent fiber. In the liquid-retaining sheet, the transparency shown below is adjusted to not more than 0.27.
Transparency=Whiteness (%) of a sheet impregnated with 700% by mass of water relative to the sheet mass/Basis weight (g/m.sup.2) The transparent fiber may contain a cellulose-series fiber substantially free from a carboxyl group (in particular, a regenerated cellulose fiber such as a solvent-spinning cellulose-series fiber). The proportion of the solvent-spinning cellulose-series fiber may be not less than 30% by mass in the transparent fiber. The liquid-retaining sheet may be a skin care sheet (in particular, a facial mask) that is impregnated with a liquid component containing a cosmetic preparation. The liquid-retaining sheet has an improved transparency in a wet state in spite of a nonwoven structural member contained in the sheet and shows a suitable strength in a wet state.

Disclosed are improved polymer materials. Also disclosed are fine fiber materials that can be made from the improved polymeric materials in the form of microfiber and nanofiber structures. The microfiber and nanofiber structures can be used in a variety of useful applications including the formation of filter materials.

A nonwoven substrate comprising a polyolefin and an engineering thermoplastic polymer. The engineering thermoplastic polymer may be present in the nonwoven substrate at a level of between about 1% and about 20% by weight of the nonwoven substrate. The layer of fibers is free of a compatibilizer.