Abstract: The low-shrinkage hybrid yarns comprise reinforcing filaments and matrix filaments composed of thermoplastic polymers having a lower melting point than the melting or decomposition point of the reinforcing filaments. The yarns are characterized by a 160.degree. C. hot air shrinkage of not more than 2% and a 200.degree. C. hot air shrinkage of not more than 5%. A process for producing these hybrid yarns includes the steps of feeding yarn strands moving at different speeds into an entangling jet, heating a matrix feed yarn during the feeding thereof into the entangling jet, entangling the feed yarn strands, and taking off the strands with or without shrinkage and additional heating.

Abstract: The low-shrinkage hybrid yarns comprise reinforcing filaments and matrix filaments composed of thermoplastic polymers having a lower melting point than the melting or decomposition point of the reinforcing filaments. The yarns are characterized by a 160.degree. C. hot air shrinkage of not more than 2% and a 200.degree. C. hot air shrinkage of not more than 5%.These yarns are useful for producing composites.

Abstract: Described is a composite comprising at least one textile sheet construction composed of synthetic polymer and hybrid yarn comprising reinforcing fiber and lower melting bonding fiber. Also described is a net comprising in at least one direction hybrid yarns composed of reinforcing fiber and of lower melting bonding fiber. The composites can be used for producing bituminized roofing and sealing membranes.

Abstract: Two-component loop yarns composed of core and effect filaments are made of synthetic polymers and comprise the following features. At least some of the effect filaments are made of polyester, and at least some of the effect filaments have a breaking extension of from 35 to 70%, preferably from 35 to 60%. Moreover, at least some of the effect filaments have a birefringence of from 100*10.sup.-3 to 150*10.sup.-3, in particular from 125*10.sup.-3 to 140*10.sup.-3, and at least some of the effect filaments have a hot air shrinkage of 200.degree. C. of from 3 to 14%, in particular from 5 to 10%. The effect filaments have a filament linear density of not greater than 1.5 dtex.

Abstract: There is described a particularly gentle and fast process for heating and drawing yarns by passing them contactlessly through a heating apparatus at high speed.Polyester fibers have a tenacity index TI equal to or greater than 50 and a molecular orientation MO equal to or greater than 20 or a compliance COM equal to or less than 12 and a storage modulus index SMI equal to or greater than 100.The polyester fibers of the invention can be used in particular for reinforcing plastics or for producing dimensionally stable textile fabrics.

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: A gentle and fast process for heating yarns passing contactlessly through a heating apparatus. The process includes the steps of preheating a heat transfer has to a temperature above the desired final yarn temperature, feeding the preheated heat transfer gas to the yarn duct so that it impinges essentially perpendicularly on the moving yarn and along a length such that the yarn heats up to the desired elevated temperature within the heating apparatus. The present invention may be used for heating air jet textured yarns and for setting two component loops sewing yarns. The invention further relates to an apparatus for carrying out the process including a preheating means, a duct in the form of a tube drilled with holes, feed lines, and a distributor chamber enabling the heat transfer gas to impinge radially upon the outside of the yarn moving contactlessly in the duct.

Abstract: Two-component loop sewing yarn composed of core and effect filaments of high tenacity and low shrinkage made of synthetic polymers, having an ultimate tenacity of above 40 cN/tex, a thermoshrinkage at 180.degree. C. of below 8% and an ultimate tensile strength elongation of below 18%, has a total count of 200 to 900 dtex, its core filaments and effect filaments being in a weight ratio of 95:5 to 70:30 with the linear density of the core filaments being 8 to 1.2 dtex and that of the effect filaments being 4.5 to 1 dtex.

Abstract: There are described two-component loop yarns composed of core and effect filaments made of synthetic polymers, having a final tenacity of at least 30 cN/tex and a final linear density of less than 200 dtex and wherein the core and effect filaments each have a total linear density of in each case of less than 100 dtex.The yarns described are preferably useful as sewing yarns.

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: Two-component loop sewing yarn composed of core and effect filaments of high tenacity and low shrinkage made of synthetic polymers, having an ultimate tenacity of above 40 cN/tex, a thermoshrinkage at 180.degree. C. of below 8% and an ultimate tensile strength elongation of below 18%, has a total count of 200 to 900 dtex, its core filaments and effect filaments being in a weight ratio of 95:5 to 70:30 with the linear density of the core filaments being 8 to 1.2 dtex and that of the effect filaments being 4.5 to 1 dtex.

Abstract: An intermingling nozzle for filaments and yarns is described. The intermingling nozzle comprises a reedlike side by side arrangement of alternate yarn channel and closing plates. In the yarn channel plate sides adjoining the closing plates, grooves are formed as yarn channels and perpendicularly thereto as blowing channels. The closing plates are rotatable with respect to the yarn channel plates, specifically between an open position, in which they give access to the yarn channels to allow yarns to be inserted, and a closed position, in which they cover up the yarn channels. The intermingling nozzle is suitable in particular for intermingling high-count yarns, for example for reinforcing fabrics and tire cords.