Abstract: A novel synthetic yarn is disclosed which comprises fibers of different lengths (as specified). At least three groups of synthetic fibers are present in the yarn, with the synthetic fibers within each group being substantially uniform in length. The substantially uniform length of each group of synthetic fibers present in the yarn differs from the substantially uniform length of the synthetic fibers in the other groups. The use of such mixtures of fiber lengths in a synthetic yarn enables the yarn to exhibit physical characteristics such as high bulk which more closely resemble the characteristics of natural fiber-containing yarns. Fabrics having improved physical characteristics may also be produced from the novel synthetic yarns disclosed.

Abstract: A yarn is prepared from a mixture of textile staple fibers and active carbon staple fibers which consists of 5 to 75%, preferably 20 to 40%, of the latter by weight, by chopping active carbon monofilaments into staple fibers, mixing them with textile staple fibers in a liquid vehicle, separating the fibers from the liquid vehicle and spinning them to yarn which can be used in weaving fabrics of tensile strengths of as much as 2000 newtons per 5 centimeters, which in turn can be used in making filters and protective suits.

Abstract: A novel synthetic yarn is disclosed which comprises fibers of different lengths (as specified). At least three groups of synthetic fibers are present in the yarn, with the synthetic fibers within each group being substantially uniform in length. The substantially uniform length of each group of synthetic fibers present in the yarn differs from the substantially uniform length of the synthetic fibers in the other groups. The use of such mixtures of fiber lengths in a synthetic yarn enables the yarn to exhibit physical characteristics such as high bulk which more closely resemble the characteristics of natural fiber-containing yarns. Fabrics having improved physical characteristics may also be produced from the novel synthetic yarns disclosed.

Abstract: A double layered yarn having a sheath and core structure is prepared through a roving process, drawing process or fine spinning process. The sheath portion of the yarn is composed of staple fibers which have a high thermal shrinkage in boiling water of at least 5%, and the blended fiber ratio of which is between 50% and 25%. The core portion of the yarn is composed of staple fibers which have a property being spontaneously extensible, and the blended fiber ratio of which is between 25% and 75%. The double layered yarn is subjected to a heat treatment in hot water, and a bulky spun yarn which comprises staple fibers A and B is obtained. The staple fibers A are concentrated toward the inside of the bulky spun yarn after they are shrunk. The ends of staple fibers B are held within the inside of the bulky spun yarn, and the intermediate portions of fibers B are bulged as a loop from the body portion of the bulky spun yarn, after the fibers B are spontaneously extended.

Abstract: A fiberfill blend for making into a batt for heat-bonding of said batt to make it especially suitable for use in garments, consisting essentially of three ingredients: (a) two of the ingredients are crimped polyester staple fiber of lower denier than has commonly been used heretofore in polyester fiberfill, namely less than about 3 denier; (1) one of these polyester fiberfill ingredients is slickened with a durable coating; (2) the other of these polyester fiberfill ingredients is unslickened; each of ingredients (1) and (2) constitutes 25 to 75% of the polyester fiberfill (a); (b) the third ingredient is crimped binder fiber of a polymer having a melting point lower than that of the (a) ingredients; the binder fiber is present in amount 10 to 30% of the blend; the remaining 70 to 90% of the blend is the low denier polyester fiberfill.

Abstract: A roving formed from a first kind of staple fibers, each of which is at least 3 denier, is interposed with a randomly mixed sliver formed from a second kind of staple fibers, each of which is between 1.5 denier and 3 denier, and a third kind of staple fibers, each of which is at most 1.5 denier, the thermal shrinkage of the second kind of staple fibers being higher than that of the third kind of staple fibers. The roving and the randomly mixed sliver are twisted together so that the sliver wraps around the roving in order to form a double layered roving. After the double layered roving is subjected to fine spinning, it is then subjected to a heat treatment. As a result, a multi-layered bulky spun yarn is obtained.

Abstract: A method for producing chemically untreated fire resistant fiber blends includes the steps of separately blowing and carding bundles of selected matrix and staple fibers, respectively, to form separate slivers of each of the two fibers. Given proportions of each fiber are then combined during a common drawing step to form a bulky blended sliver which is then conventionally processed to produce a fire resistant yarn. The yarn is suitable for knitting or weaving to provide fabrics which far exceed current government fire resistant standards.

Abstract: This invention relates to fiber blends, yarns and fabrics for use in lightweight garments offering protection against brief exposure to extreme thermal fluxes, the fiber blend comprising a component that fuses within 10 seconds upon exposure to a heat flux of 2 cal./cm..sup.2 /sec. and a component that in fabric form exhibits a flame strength of at least 20 mg. per denier for at least 10 seconds during exposure to a heat flux of 2 cal./cm..sup.2 /sec.

Abstract: An antistatic composite yarn is obtained by wrapping a core yarn with a covering yarn. The core yarn has an electrically conductive coating thereon which comprises a polymeric matrix and a finely divided electrically conductive material therein. The antistatic composite yarn and a pile yarn are used to produce a tufted antistatic carpet.Polyamide fiber is preferably used as the covering yarn and the pile yarn. The covering yarn contains at least 40% by weight of polyamide fiber, whose content of amino end group is at least 1.0.times.10.sup.-5 mol/g higher than that of polyamide fiber contained in the pile yarn.In the case the pile yarn is composed of at least two kinds of polyamide fibers which differ from one another in the content of amino end group, one of the polyamide fibers has the content of amino end group at least 1.0.times.10.sup.-5 mol/g lower than that of another.