A Yarn is described composed of an untwisted staple sliver and of at least one filament wound around this sliver. The denier of the winding filamentary yarn is under 50 dtex, the elongation at break of the winding filamentary yarn is at least as great as the elongation at break of the staple fibers; the strength at a specific load of the winding filamentary yarn at 4% of elongation is at least 10 g. Moreover, the shrinkage factor of the winding filamentary yarn is within the same range as the shrinkage factor of the staple fibers. Also, at least 85% of the staple fibers are longitudinally orientated in the sense of the yarn direction. Furthermore, a process is described for the manufacture of a wrapped yarn by wrapping at least one filamentary yarn around stretched, highly oriented staple fibers being led through the hollow shaft of a rotating filamentary yarn bobbin. The winding filamentary yarn is withdrawn from the filamentary yarn bobbin and also led through the hollow shaft of this filamentary yarn bobbin. During this processing step and after having stretched the staple sliver, a filament of denier 1 - 50 dtex, the tension of which is at most 5 g, is wrapped around the staple sliver.
A fabric suitable for use in making sandbags and the method of making the same wherein the fabric is woven from a yarn of twisted staple acrylic fibers having a fiber length of about 7 to 20 cm and a denier per filament of about 5 to 15, preferably 10 to 15, the yarn having a total denier of about 200 to 2650. The yarn is wrapped with a continuous filament yarn of a type which is degraded by ultraviolet light, with the wrapping being done in such a manner that fuzziness of the yarn is reduced to the point where the yarn can be woven into fabric without the use of size and at a weaving efficiency of at least about 70%.
Multi-component spun yarn. The surface of an open-end spun yarn (staple fibers) having a small degree of twist is covered with a continuous yarn twisted in the same direction. The length of the continuous yarn is greater than that of the open-end spun yarn. Manufacturing method and apparatus are also disclosed.
A mechanism for the production of wrapped yarn which consists of a bundle of spun fibers wrapped around a binding thread. A hollow spindle 5 is supported between a pair of delivery rolls 1, 2 and a pair of draw-off rolls 3, 4. A rotating binding thread bobbin 7 is arranged coaxially with the hollow spindle 5 and is enclosed by a housing 8. An air flow which can be generated in the housing and/or introduced into the housing causes the pressure within the housing to be built up so as to prevent fibers and the like from entering an exit hole carried in a cover 80 provided on the housing.
A pile fabric is formed from interengaging ground yarns and cut pile tufts formed of wrap yarns extending upwardly from the ground yarns to form the face of the fabric. Each of the wrap yarns comprises a body strand of untwisted staple fibers and a binder strand helically wrapped around the body strand. The binder strands are preferably crimped textured strands and formed of a thermoplastic polymer having heat shrinkable and fusible properties and a relatively low melting point of less than about 300.degree. F. The staple fibers and ground yarns are formed of a material unaffected at the relatively low melting point of the binder strand. When a moderated amount of heat is applied to a cut pile fabric formed from such wrap yarns, the binder yarns shrink and are retractably positioned inwardly away from the face of the pile fabric and are hidden among the pile tufts and not visible. When a greater amount of heat is applied to the pile fabric, the binder strands melt and thereafter resolidify into randomly arranged discrete portions of binder strand material which fusibly interconnect the staple fibers with one another and with the ground yarns. The shrinking, melting and resulting improved properties of the pile fabric can be further enhanced by appropriate finishing steps.
A pile fabric is formed of interengaging ground yarns and cut pile tufts. The tufts are formed of wrap yarns extending upwardly from the ground yarns and forming the face of the fabric. Each of the wrap yarns comprises a body strand of untwisted staple fibers and a crimped textured binder strand which has extensible and retractable properties. In the wrap yarn, the binder strand is helically wrapped around the body strand in an axially extended and tensioned condition and is reduced in bulk compared to the condition the binder strand would assume when relaxed. When tufts formed of such wrap yarns are cut to form the face of a cut pile fabric, the binder strands retract and position themselves inwardly away from the face of the pile fabric so as to be hidden among the pile tufts and not visible. The retraction of the binder yarns and the appearance, hand and integrity of the resulting fabric can all be enhanced by various finishing processes.
