A composite yarn (e.g. for weaving) may include at least one fibrous core made of a core material including recycled fibers (e.g. recycled cellulosic fibers and/or recycled synthetic fibers) and a sheath surrounding the fibrous core. The sheath may be made of a sheath material, such as a sheath material including cellulosic fibers and/or synthetic fibers, having a greater axial strength than the core material.

Provided herein are methods for producing a fiber from a waste material comprising: (i) fraying a waste material to form a fiber base; (ii) carding the fiber base to form a recovered fiber; and (iii) spinning the recovered fiber. The waste material may comprise manufacturing scraps, damaged materials, selvedges, or combinations thereof. In some embodiments, the method may further comprise reducing the size of the waste material prior to fraying and/or blending the fiber base. Also described herein is a fiber produced from waste material using the disclosed methods.

Provided herein are methods for producing a fiber from a waste material comprising: (i) fraying a waste material to form a fiber base; (ii) carding the fiber base to form a recovered fiber; and (iii) spinning the recovered fiber. The waste material may comprise manufacturing scraps, damaged materials, selvedges, or combinations thereof. In some embodiments, the method may further comprise reducing the size of the waste material prior to fraying and/or blending the fiber base. Also described herein is a fiber produced from waste material using the disclosed methods.

The present invention refers to yarns made of hollow trilobal cross section filaments, comprising from 90 to 99% of polypropylene, and between 1 and 10% of other polyolefin resins, for the application on dental floss. This invention additionally refers to the production process of the yarns made of hollow trilobal cross section filaments. This invention additionally refers to dental floss comprising hollow trilobal cross section filaments, and the use of hollow trilobal cross section filaments for the manufacture of dental floss. The yarn described in this invention has linear density or title in the range from 400 to 1200 dtex, and it is twisted with a twist level from 10 to 160 twists per meter.

The present invention refers to yarns made of hollow trilobal cross section filaments, comprising from 90 to 99% of polypropylene, and between 1 and 10% of other polyolefin resins, for the application on dental floss. This invention additionally refers to the production process of the yarns made of hollow trilobal cross section filaments. This invention additionally refers to dental floss comprising hollow trilobal cross section filaments, and the use of hollow trilobal cross section filaments for the manufacture of dental floss. The yarn described in this invention has linear density or title in the range from 400 to 1200 dtex, and it is twisted with a twist level from 10 to 160 twists per meter.

A cooling material includes opposite top and bottom surfaces and a central portion positioned between the top and bottom surfaces. The top surface includes a first fiber. The bottom surface includes a second fiber. The middle portion includes the first and second fibers and a third fiber. Methods of manufacture are included.

The present invention relates to a composite yarn, a preparation method thereof and an elastic fabric, wherein the composite yarn comprises a core yarn and an outer wrapping yarn, wherein the core yarn further comprising at least one piece of elastic filament, and wherein the outer wrapping yarn is made of short fiber, wherein the outer wrapping yarn is spirally wrapped on the core yarn, wherein drafting ratio of the core yarn is 1-1.5 times.

The present invention relates to a composite yarn, a preparation method thereof and an elastic fabric, wherein the composite yarn comprises a core yarn and an outer wrapping yarn, wherein the core yarn further comprising at least one piece of elastic filament, and wherein the outer wrapping yarn is made of short fiber, wherein the outer wrapping yarn is spirally wrapped on the core yarn, wherein drafting ratio of the core yarn is 1-1.5 times.

A type of polyester yarn for an industrial sewing thread and preparing method thereof are provided. The preparing method is composed of a viscosity enhancing by a solid state polycondensation and a melt spinning for a modified polyester, and the modified polyester is a product of esterification and polycondensation of evenly mixed terephthalic acid, ethylene glycol, tert-butyl branched dicarboxylic acid, trimethylsilyl branched diol and a doped Sb.sub.2O.sub.3 powder, wherein the tert-butyl branched dicarboxylic acid is selected from the group consisting of 5-tert-butyl-1,3-benzoic acid, 2-tert-butyl-1,6-hexanedioic acid, 3-tert-butyl-1,6-hexanedioic acid and 2,5-di-tert-butyl-1,6-hexanedioic acid. Moreover, the modified polyester is dispersed with a doped ZrO.sub.2 powder. An obtained fiber has an intrinsic viscosity drop of 23-28% when stored at 25° C. and R.H. 65% for 60 months.

A type of polyester yarn for an industrial sewing thread and preparing method thereof are provided. The preparing method is composed of a viscosity enhancing by a solid state polycondensation and a melt spinning for a modified polyester, and the modified polyester is a product of esterification and polycondensation of evenly mixed terephthalic acid, ethylene glycol, tert-butyl branched dicarboxylic acid, trimethylsilyl branched diol and a doped Sb.sub.2O.sub.3 powder, wherein the tert-butyl branched dicarboxylic acid is selected from the group consisting of 5-tert-butyl-1,3-benzoic acid, 2-tert-butyl-1,6-hexanedioic acid, 3-tert-butyl-1,6-hexanedioic acid and 2,5-di-tert-butyl-1,6-hexanedioic acid. Moreover, the modified polyester is dispersed with a doped ZrO.sub.2 powder. An obtained fiber has an intrinsic viscosity drop of 23-28% when stored at 25° C. and R.H. 65% for 60 months.