Abstract: Water vapor transport membranes for ERV and other water vapor transport applications are provided. The membranes include a substrate and an air impermeable selective layer coated on the substrate, the selective layer including a cellulose derivative and a sulfonated polyaryletherketone. In some embodiments the sulfonated polyaryletherketone is in a cation form and/or the selective layer includes sPEEK and CA in an sPEEK:CA (wt.:wt.) ratio in the range of about 7:3 to 2:3. Methods for making such membranes are provided. The methods include applying a coating solution/dispersion to a substrate and allowing the coating solution/dispersion to dry to form an air impermeable selective layer on the substrate, the coating solution/dispersion including a cellulose derivative and a sulfonated polyarylether ketone. In some embodiments the sulfonated polyaryletherketone is in a cation form and/or the coating solution/dispersion includes sPEEK and CA in an sPEEK:CA (wt.:wt.) ratio in the range of about 7:3 to 2:3.

Abstract: A flame resistant fabric is formed from synthetic fibers, such as polyester fibers or non-aramid polyamide fibers. A first flame retardant is incorporated into the fibers by being intimately mixed with the polymer used to form the fibers. A second flame retardant is then surface applied to the fabric or to the yarns used to form the fabric. The fabric has a total flame retardant compound concentration of at least 5000 ppm. In one embodiment, the fabric can be combined with other fabric layers to produce a composite fabric product.

Abstract: The present penetration-resistant fabric manufacturing method which prevents yarn breakage during the manufacturing process comprises the steps of: (i) blending a fusible yarn and a support yarn to form a blended yarn; (ii) the blended yarn and an elastomeric yarn are formed into a fabric; (iii) treating the fabric by heating so that the fusible yarn melts and spreads over the fabric; and (iv) cooling the fabric to form a penetration barrier. The present invention prevents yarn breakage during the manufacturing process.

Abstract: A yarn having characteristics required in a gland packing is obtained by, when the yarn is to be constructed by fibers such as organic fibers, finding relationships between the required characteristics and the value of the limiting oxygen index (LOI), and adequately defining the level of the required characteristics. A yarn is formed by twisting fibers having a limiting oxygen index of 21 to 30, preferably 22 to 26. The fibers contain fibers in which a flat ratio is defined as 1.1 to 2, the flat ratio being a value obtained by dividing the maximum value of an interval between two parallel straight lines in a state where a section of each of the fibers is interposed between the straight lines, by the minimum value. The fibers contain fibers in each of which a sectional shape has one or more recesses having a depth of 0.4 ?m or more.

Abstract: A method for fabricating natural polymer yarn comprises the following steps: (a) forming a natural polymeric long fiber by wet spinning or electro spinning from a natural polymer solution; (b) combining the natural polymeric long fiber and at least one polymeric fiber by a false twist texturing process to form a natural polymeric yarn. A natural polymer yarn relates to the method. A natural polymer fabric includes said natural polymer yarn. A method of using said natural polymer fabric for medical dressing. By means of a false twist texturing process, the natural polymer yarn with enhanced tensile strength and elongation could reduce the drawback of conventional wound dressing products which lack strength and stretchiness in a wet condition.

Abstract: Cut resistant yarn containing at least one single yarn, the single yarn containing high performance filaments and/or high performance staple fibers, characterized in that the single yarn containing the high performance filaments and/or the high performance staple fibers has a free volume of at least 15%. The yarn is suited for the production of protective garment, like gloves etc.

Abstract: An absorbable multifilament draw-textured yarn having a bulky structure, and a manufacturing method and medical use thereof The absorbable multifilament draw-textured yarn is obtained by draw-texturing a multifilament made of an absorbable polymer and has bulkiness and a superior soft touch, which are the characteristics of draw-textured yarns. As a result of partially imparting a bulkiness of 150-1000% to the multifilament draw-textured yarn, it is possible to culture cells in the bulky structure, and the multifilament draw-textured yarn is suitable for cell delivery or drug delivery.

Abstract: To provide a sewing thread that is excellent in high-speed sewability and automatic sewing characteristics. A sewing thread includes a plurality of under-twisted yarns provided with upper-twist, the yarns each being composed of a sheath-core structure yarn composed of two or more multifilament yarns, wherein part of the sheath-core structure yarn protrudes as loops on a yarn surface, the loops being composed of 50 to 300 loops/m with 0.7 to less than 1.2 mm length and 10 or less loops/m with 1.2 mm or more length, and wherein the yarns have a strength of 4 to 6 CN/dtex.

Abstract: A moisture absorbing hygroscopic fiber having high whiteness, characterized in that (1) acrylic fiber comprising acrylonitrile copolymer where a (meth)acrylate compound as a copolymer component is less than 5% by weight is treated with a hydrazine compound whereby introduction of crosslink and increase in nitrogen content to an extent of 1.0 about 10.0% by weight is carried out, (2) treatment with an aqueous solution of alkaline metal salt is carried out whereby carboxyl group of a metal salt type by which CN group is hydrolyzed is produced in an amount of 4.0 about 10.0 meq/g and (3) a reducing treatment by a reduction treatment agent selected from a group consisting of hydrosulfite, thiosulfate, sulfite, nitrite, thiourea dioxide, and ascorbate compound is carried out.

Abstract: A method and apparatus for production of a yarn, by plying, twisting or covering several staple yarns, subjected to a prior transformation, is provided. At least one of the staple yarns is different from the others and/or is subjected to a different prior transformation. The prior transformation may be carried out in parallel in the same machine, by independent transformation members able to be independently controlled. A slackening of yarn tension resulting from the prior transformation to give the desired tension at an assembly point is carried out on yarn feeding devices. Routing of the yarns is achieved by guide members towards the point of assembly, where the staple yarns are combined and arranged in parallel. A bobbin receives the assembled yarns in a device, constituting or associated with a positive feed device operating without slippage with relation to the yarn.

Abstract: The present invention provides a synthetic fiber and methods for its use and formation. The present invention may comprise a fiber component that is a twisted bundle comprised of multiple strands of a nonfibrillating monofilament, the degree of twist being greater than about 0.9 turns/inch (about 0.36 turns/cm). The present invention may further comprise another fiber component, discrete from the twisted fiber component, that is fibrillated.

Abstract: The invention relates to an asbestos-free binding yarn for fastening incandescent bodies to burners of incandescent lamps whose incandescent bodies after the fastening are exposed to a flame, wherein the binding yarn consists of a fireproof material, preferably silica yarn. For improving the knotting ability of the yarn it is envisaged that the binding yarn after exposure in the flame has a diameter changed of less that 50% of its original diameter. The subject-matter of the invention is also the use of the binding yarn on an incandescent body for increasing its retention and durability.

Abstract: A multicolored effect yarn for use in carpeting includes a core yarn which exhibits substantially zero twist and is formed of a multiplicity of BCF singles yarns, at least one of which has a different color from another, and which are entangled at first and second frequencies of entanglement points and different degrees of entanglements, and a wrapper yarn helically wrapped around the core yarn and has a lower denier than any of the singles yarns.

Abstract: A cut-resistant yarn formed of a multifilament yarn, each filament of a polyester material having ceramic platelets embedded to provide a yarn having cut resistance, and the yarn having a friction-textured false twist inserted therein to provide a surface exhibiting comfort characteristics rendering the yarn suitable for use in apparel. An embodiment of the method of forming a cut-resistant yarn according to the invention includes the steps of providing a multifilament yarn. The filament is a polyester material having ceramic platelets embedded to provide a yarn having cut-resistance. False twist by the friction-texturing method is inserted to provide a surface exhibiting comfort characteristics rendering the yarn suitable for use in apparel.

Abstract: The invention provides an entangled continuous filament yarn comprising at least two bicomponent filaments each comprising poly(trimethylene terephthalate) and poly(ethylene terephthalate), wherein the entangled yarn has a node frequency of about 40 to 50 nodes/m, a Crimp Potential of at least about 40%, substantially no twist, and a standard deviation of intervals between nodes of no more than about 1.1 cm. The invention further provides a process for making such an entangled yarn.

Abstract: A self-set yarn made from bicomponent fibers forms helical crimps that lock in twist and form bulk.

Abstract: The present invention relates to cut resistant yarns. More particularly, it relates to a cut resistant yarn comprising a plurality of cut resistant filaments and at least one elastomeric filament, as well as fabrics and articles such as gloves, comprising such cut resistant yarns.

Abstract: A cut-resistant yarn formed of a multifilament yarn, each filament of a polyester material having ceramic platelets embedded to provide a yarn having cut resistance, and the yarn having a friction-textured false twist inserted therein to provide a surface exhibiting comfort characteristics rendering the yarn suitable for use in apparel. An embodiment of the method of forming a cut-resistant yarn according to the invention includes the steps of providing a multifilament yarn. The filament is a polyester material having ceramic platelets embedded to provide a yarn having cut-resistance. False twist by the friction-texturing method is inserted to provide a surface exhibiting comfort characteristics rendering the yarn suitable for use in apparel.

Abstract: A cut-resistant yarn formed of a multifilament yarn, each filament of a polyester material having ceramic platelets embedded to provide a yarn having cut resistance, and the yarn having a friction-textured false twist inserted therein to provide a surface exhibiting comfort characteristics rendering the yarn suitable for use in apparel. An embodiment of the method of forming a cut-resistant yarn according to the invention includes the steps of providing a multifilament. The filament is a polyester material having ceramic platelets embedded to provide a yarn having cut-resistance. False twist by the friction-texturing method is inserted to provide a surface exhibiting comfort characteristics rendering the yarn suitable for use in apparel.

Abstract: A process for combining dyed or melt pigmented textile denier accent yarns in small yarn sizes, into a small building block carpet denier bundle to achieve a face yarn bundle having a wide range of special color effects and appearance, not attainable by manufacture of multi-colored carpets from carpet denier fibers alone. The carpet denier singles yarns are drawn, textured and air-jet entangled. At least one textile denier singles yarns, which is preferably a yarn having some degree of orientation, is then entangled with the carpet denier singles yarn, and the bundle is then wound up. The final yarn bundle may contain one or more fiber types, as well as at least one anti-static filament. The two types of singles yarn, i.e., the carpet denier and textile denier types, optionally have the same or different fiber cross-sections.

Abstract: The invention relates to a method for air texturizing or air entangling a metal or metal-containing monofilament yarn (7) with a multifilament yarn (2) to give a novel multifilament-metal monofilament hybrid yarn (9). The monofilament yarn (7) used may, for example, be a full-metal thread, a metal-coated chemical fiber or a metal wire strand. It is supplied to the air texturizing nozzle (5) as the stationary thread and/or the fancy yarn together with the multifilament yarn (2) and is texturized according to the invention. However, a plurality of differently textured monofilament yarns (2) can also be used. The multifilament yarn (2) or additional monofilament yarns (7) may consist of natural or synthetic continuous fibers. According to the invention, an adequately textile, twist-free, easily processible, very long-wearing and at the same time electroconductive hybrid yarn (9) is obtained.

Abstract: Melt processable perfluoropolymer forms in woven, non-woven and knitted manifestations, and products produced therefrom such as filters and filtration support media are made of melt processable single and/or multicomponent yarns from a wide range of deniers, shapes and crimps.

Abstract: The present invention provides a package, of a false twist yarn composed of polytrimethylene terephthalate fibers, characterized in that a hardness and a winding density of the package and the number of crimps of the false twist yarn thus taken up simultaneously satisfy the following conditions (1), (2) and (3): (1) 70≦hardness≦90 (2) 0.6 g/cm3≦winding density≦1.0 g/cm3 (3) hardness×the number of crimps≧520 The package of the present invention maintains a favorable package shape and is excellent in unwinding property, whereby a high-quality knit or woven fabric is obtainable.

Abstract: A sewing yarn is described, with at least two roving. yarns, which are twisted together with one another for the formation of the sewing yarn, whereby each roving yarn has the structure of a core yarn, comprising at least one first multifilament yarn component, forming a yarn core, and a second fiber yarn component spun over the core. In the cross-section of the sewing yarn, the spun fiber yarn covering of at least one roving yarn contains less than 41 individual fibers.

Abstract: Provided is a fire resistant corespun yarn. The yarn includes a core of high temperature resistant continuous inorganic filaments; a first sheath of staple fibers surrounding the core, wherein the staple fibers comprise fibers of at least one fire resistant material selected from the group consisting of meta-aramids, para-aramids, fluoropolymers and copolymers, chloropolymers and copolymers, polybenzimidazole, polyimides, polyamideimides, partially oxidized polyacrylonitriles, novoloids, poly (p-phenylene benzobisoxazoles), poly (p-phenylene benzothiazoles), polyphenylene sulfides, flame retardant viscose rayons, polyvinyl chloride homopolymers and copolymers, polyetheretherketones, polyketones, polyetherimides, polylactides, and combinations thereof; and a second sheath of staple fibers surrounding the first corespun yarn. This yarn may be woven and knit in fine, non-plied or plied form and extends the range of fineness of fabrics below heretofore achievable limits.

Abstract: Machine for combining an elastomer thread (81) with an unextendable thread (11) wound on respective spools (80,10), which comprises a first pair (20) of rollers for driving the unextendable thread (11), a heating oven (30), a false-twisting group (40), a second pair (50) of driving rollers and at least one interlacing device (60), which are arranged in sequence along the path of the thread (11), characterized in that said elastomer thread (81) is supplied upstream of the said false-twisting group (40).

Abstract: A cut-resistant combined yarn is described that includes a wire component. Kinking and knotting of the wire component resulting from stretching of the wire component during knitting is avoided by encasing the wire component within a cut resistant combined yarn that has a higher stretch resistance than the wire component. The combined yarn includes at least one strand of stainless steel, at first non-metallic strand of an inherently cut-resistant material, and a second non-metallic strand of a cut resistant material, a non-cut resistant material or fiberglass. The non-metallic strands are air interlaced with each other to form intermittent attachment areas along the lengths of the strands. At least one or the other of the strands is a multi-filament strand. During air interlacing operation, the two non-metallic strands encase the stainless steel strand in the non-metallic strands at least in some of the zones.

Abstract: A method and apparatus for producing a combined textile yarn comprising two yarn components that are false twisted to different twist levels and then combined to form a combined textile yarn. The yarn components may be twisted in the same or opposing directions, and may be drawn simultaneously with twisting to differing draw ratios before being combined.

Abstract: The present invention provides a hairiness suppressing device for an automatic winder that can perfectly balloon a spun yarn using a whirling current in a yarn passage. In a hairiness suppressing device (1) comprising a yarn inserting opening (9) that extends and opens in an axial direction of a yarn passage (8) in which a whirling current acts on a spun yarn, a wedge-shaped cover member (29) is provided that can open and close the yarn inserting opening (9). When a swiveling body (26) is swivellably moved to open the cover member (29), the yarn can be introduced into the yarn passage (8) through the yarn inserting opening (9). When the swiveling body (26) is swivellably moved to close the cover member (29), the whirling current in the yarn passage (8) is prevented from leaking from a side of the yarn passage (8).

Abstract: Crimped yarns that comprise a conjugate multifilament yarn having unique surface texture, dry touch, and stretchability; woven/knitted products comprising said crimped yarn; and production methods of crimped yarn as a conjugate multifilament yarn comprising polyester polymer components and has (a) number of crimps (CA): 2.5 crests/cm≦CA≦10 crests/cm, (b) number of developed crimps (CB): 8 crests/cm≦CB≦30 crests/cm, (c) shrinkage stress (TS): 0.0882≦TS (cN/dtex)≦0.221, (d) apparent shrinkage percentage (SC): 40%≦SC≦80%, and (e) shrinkage percentage of fiber in boiling water (SW): 2%≦SW≦8%, and produced by subjecting a crimp-forming conjugate multifilament yarn to relaxation-heat treatment.

Abstract: A self-set yarn made from bicomponent fibers forms helical crimps that lock in twist and form bulk.

Abstract: A composite textured yarn contains a component yarn A and a component yarn B each false twisted and crimped. The component yarn B is shorter in yarn length or larger in shrinkage at least after heat treatment. Single fibers of component B have thick portions and thin portions successively alternating in the longitudinal direction.

Abstract: An improved composite material of high temperature and chemical resistant material and polytetrafluoroethylene (PTFE) is provided. The composite material incorporates a coherent strand of commingled filaments of fiberglass and PTFE which is far more resistant to flex, abrasion, and chemical attack than conventional materials. Preferably filaments of expanded PTFE tow yarn and filaments of PTFE are combined through a process of air-jet texturing. Fabrics made from the composite fibers are combined with thermosetting phenolic or epoxy resins to produce pleated cartridge filter elements exhibiting superior performance in high temperature and corrosive environments.

Abstract: A permanently flame-retardant and anti-microbial air-textured yarn is formed of a plurality of substantially longitudinally extending, permanently flame-retardant filaments defining a core, and a plurality of substantially randomly extending, permanently anti-microbial filaments disposed at least about the core, the anti-microbial filaments at least partially defining a boucle-like sheath about the core. A knit or woven fabric formed with the yarn and having at lease 5% by weight of the anti-microbial filaments is characterized by an ability to pass, both after one commercial laundering and after 100 commercial launderings, both National Fire Protection Agency vertical flame retardancy test NFPA 701-1989 and at least the 85% reduction level of gram positive and gram negative bacteria of anti-microbial test NYS 63.

Abstract: A nubuck-like woven fabric comprising a two-layered structural yarn wherein ultra-fine polyester multifilaments are primarily disposed in a sheath portion and polyester multifilaments having a larger single fiber thickness are primarily disposed in a core portion, and having an apparent specific gravity of 0.35-0.7 and a shear rigidity of 0.5-1.2 gf/cm.multidot.deg. This woven fabric is produced by a method wherein a woven fabric of a two-layered structural yarn composed of (i) side-by-side type or islands-in-sea type composite multifilaments comprising (a) a readily soluble ingredient and (b) ultra-fine multifilaments-forming ingredient and (ii) highly shrinkable multifilaments, is subjected to a treatment for dissolving and removing ingredient (a) without substantial shrinkage of the two-layered structural yarn, then, the woven fabric is shrunk in a widespread state.

Abstract: A composite yarn and a method for forming the composite yarn include the composite yarn being formed from different components wherein the resultant yarn exhibits characteristics not apparent from the individual component yarns with the composite yarn being formed from a first component yarn strand and a second component yarn strand with the first and second component strands being comingled using an entanglement device with the co-mingling occurring with the first and second component strands subject to a first tension value which is subsequently increased to a second, higher tension value for winding. A method for forming such a composite yarn includes propelling the strands through the entanglement device at a first tension value, entangling the strands, imparting a second tension value to the resultant entangled strands and winding the entangled strands.

Abstract: A method for producing substantially 100% polyester yarns on an open end spinning machine is described. The process involves acting on substantially 100% polyester sliver made of high tenacity, fine denier fibers with a negative tooth combing roll to individualize the fibers and feed them to the rotor of an open end spinning machine. Superior quality industrial gauge yarns can be produced from fine denier, high tenacity polyester fibers according to this method at a high rate of throughput and with few ends down.

Abstract: A method for producing substantially 100% polyester yarns on an open end spinning machine is described. The process involves acting on substantially 100% polyester sliver made of high tenacity, fine denier fibers with a negative tooth combing roll to individualize the fibers and feed them to the rotor of an open end spinning machine. Superior quality industrial gauge yarns can be produced from fine denier, high tenacity polyester fibers according to this method at a high rate of throughput and with few ends down.

Abstract: Described is a hybrid yarn consisting of at least two varieties of filaments, at least one variety (A) having a lower heat shrinkage and at least one variety (B) a higher heat shrinkage than the rest of the filaments of the hybrid yarn, whereinthe first variety (A) of filaments has a dry heat shrinkage maximum of below 7.5%,the second variety (B) of filaments has a dry heat shrinkage maximum of above 10%, andits dry heat shrinkage tension maximum is so large that the total shrinkage force of the proportion of the second variety of filaments is sufficient to force the lower-shrinking filaments present to undergo crimping,the optionally present, further filament varieties (C) have dry heat shrinkage maxima within the range from 2 to 200%and at least one of the filament varieties (B) and/or (C) is a thermoplastic filament whose melting point is at least 10.degree. C., preferably 20.degree. to 100.degree. C., in particular 30.degree. to 70.degree. C.

Abstract: Polyester carpets of poly(trimethylene terephthalate) are disclosed which have excellent stain-resistance, texture retention and resistance to crushing. The bulked continuous filament yarn used to make the carpets and the process for making the yarns are also disclosed.

Abstract: A method is disclosed for increasing the dyeability of polyester yarn and comprises heating the partially oriented yarn to a temperature between its crystallization temperature and its melting point while preventing the partially oriented yarn from shrinking, and immediately thereafter draw texturizing the partially oriented yarn to a desired draw ratio and texturization.

Abstract: The present invention relates to a pile material composed of a textile backing composed of a knit or woven and bound-in loop-forming pile yarns, the textile backing consisting of a multifilament hybrid yarn composed of a mixture of lower melting and crimped higher melting filaments, said pile material being capable of three-dimensional deformation and having a backing which can be consolidated by heat treatment. The pile material of the invention has a pleasantly soft, textile hand and can be used for example as cover for seating or for textile surface decoration of complicatedly styled contours, for example the inner surface of motorcardoors.

Abstract: A yarn formed from a blend of nylon fibers is disclosed. The yarn exhibits improved bulk characteristics and, when utilized as pile yarn in carpet constructions, provides a carpet with improved appearance retention properties with respect to tuft endpoint definition and lack of matting.

Abstract: The present invention is directed to a fiber blend useful in the manufacture of carpet yarn used for pile in carpet construction. The blend includes, by weight based on the weight of the total blend, about 40% to about 70% normally crimped fibers, about 5% to about 50% crimpset fibers and about 4% to about 40% high shrinkage fibers having a shrinkage value of from about 15% to about 50%. Carpets including pile yarn formed from the blends of the present invention exhibit superior resistance to watermarking as well as other desirable characteristics.

Abstract: A bicomponent, reversible crimp filament useful in textile and fabrics applications is disclosed. The filament is characterized by a total shrinkage of between about 25 percent and about 50 percent, a fiber shrinkage of between about 2 percent and about 20 percent, a crimp shrinkage of about 20 percent and about 38 percent and a basic dye level of less than about -8.

Abstract: An improved composite fiber of fiberglass and polytetrafluoroethylene (PTFE) is provided. The composite fiber comprises a coherent strand of commingled filaments of fiberglass and PTFE which is far more resistant to flex, abrasion, and chemical attack than previous fiberglass fibers. Preferably filaments of expanded PTFE tow yarn and filaments of PTFE are combined through a process of air-jet texturing. The fibers of the present invention have a wide range of possible uses, including being formed into a fabric and employed as filter media.

Abstract: There is described an intermingled multifilament yarn comprising high modulus monofilaments made for example of aramid, carbon or glass and a process for producing this yarn. Conventional air intermingling is impracticable for high modulus yarns since they tend to break, because of their brittleness, which leads in particular to an appreciable reduction in the tenacity. The invention proposes carrying out the intermingling at elevated temperature--either by preheating the yarn or by heating the intermingling air. It is found, surprisingly, that, although the entanglement spacings are relatively low, the tenacity remains substantially unaffected and in some instances is even raised. The multifilament yarn produced by this process is noteworthy in particular for the low number of broken monofilament ends. The invention can also be applied to commingled yarns, yarns which are part high modulus filaments and part thermoplastic filaments.

Abstract: Denim fabric is made from warp yarn which is at least 30% novelty cotton yarn having irregularly spaced effects (e.g. slubs) about one-half inch to two inches in length. The cotton novelty yarn is made by separating cotton sliver into cotton fibers, and acting on the cotton fibers with a negative wire combing roll, and then twisting the cotton fibers into the cotton novelty yarn. The negative wire combing roll has a tooth angle of about -0.01 to -15.degree. (e.g. about -2.degree.). The novelty cotton yarn is combined with at least 10% conventional novelty yarn or non-slub open end or ring spun yarn and made into a warp of about 54-100 ends per inch, and may be ring dyed (with indigo, vat, sulphur, pigment or reactive dye) so that the core of the yarn remains white. The warp is woven with a filling yarn to produce a denim fabric with a weight of about 5 oz. -17 oz. per sq. yd. having the weave and yarn size selected so that a tight construction is provided which highlights the slubs.

Abstract: A yarn with the appearance of a spun yarn, made from polyamide-based filaments. The yarn has crimped bulked parts, and parts which are both tight and interlaced, has a cohesion factor lying between 90 and 140 knots/meter, a Young's modulus lying between 100 and 150 cN/tex, and a difference in orientation between the two populations of filaments, evaluated by measurement of the sonic modulus, lying between 25 and 50 cN/tex. The textile articles obtained from this yarn simultaneously have a soft feel, bulk and strength.

Abstract: The invention relates to a novel type of polyolefine yarns with good performance in the manufacture of rugs and carpets, made-up by admixing polypropylene filaments with polyethylene filaments, and by subjecting said filaments mixture to a temperature of from 125.degree. C. up to 130.degree. C., which substantially equals the melting temperature of the polyethylene filaments, whereby said polyethylene filaments become melted while the polypropylene filaments, with higher melting point, remain solid and stable, and with said melting of the polyethylene filaments constituting welding points for said polypropylene filaments, bulking and shaping the resulting yarn.