JPS6319610B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a highly twisted special composite yarn, and more specifically, two or more thermoplastic multifilament yarns are supplied to an intermittent false twisting area at different yarn feeding speeds, and the yarn feeding rate is higher than that of the yarn feeding speed. By adopting a special yarn feeding method in which the yarn feeding speed of the yarn is changed in response to intermittent false twisting, the untwisted portion having a twist in the false twisting direction and the untwisted portion having a twist in the false twisting/untwisting direction can be separated. The effect of alternating twist formation, in which over-untwisted portions having a twist of This invention relates to a method for producing a special composite yarn with strong twist properties that can provide strong twist effects such as a smooth feel, a heavy feel, a drape property, and an elastic texture that are much higher than the strong twist effects caused by strong twist. . Conventionally, as a technique for alternately forming untwisted parts and overtwisted parts in false twisting,
Publication No. 12891, Japanese Patent Publication No. 14615, Publication No. 14615, Japanese Patent Publication No. 1973
-8414 Publication, JP-A-49-108353, JP-A-Sho
This method has been proposed in JP-A No. 51-49949, Japanese Patent Application Laid-open No. 53-61745, etc. These yarn twisting techniques utilize the transient phenomenon of twist propagation, and depending on the yarn speed and the period of false twisting, the length of the untwisted part and the overly untwisted part can be 1 to 2 m or more. It is possible to form alternating twist yarns of up to 100 mm. However, in all of these conventional techniques, the twist density is about the same as that of ordinary twisted yarn [approximately 3000/√T/M (D: yarn The number of twists required to achieve a strong twist effect is 8000/√T/M, which is much lower than the twist density of 8000/√T/M, preferably 12000/√T/M or more. For this reason, it was not possible to provide a sufficiently high degree of strong twisting effect. In order to eliminate the drawbacks of the conventional method, the present inventors have grasped the phenomenon of alternating twist formation in intermittent false twisting and investigated the principle thereof. Differently, by applying a special processing operation to change the yarn feeding speed of the yarn with a higher yarn feeding speed among two or more supplied yarns with different yarn feeding speeds in response to intermittent false twisting. The present invention was achieved based on the finding that the twisting effect of alternate twisting can be greatly enhanced, and that a winding configuration in which the sheath yarn is wound around the core yarn can pseudo-improve the strong twisting effect. An object of the present invention is to provide a method for producing a highly twisted special composite yarn having an extremely high twisting effect. That is, when the present invention intermittently false-twists two or more thermoplastic multifilament yarns by repeatedly twisting and stopping twisting, the two or more thermoplastic multifilament yarns are fed at different yarn feeding speeds. At the same time, the yarn with a higher yarn feeding speed is set at a higher speed during yarn twisting in response to intermittent false twisting, and when yarn twisting is stopped, the yarn feeding speed is set higher than the yarn feeding speed of the yarn with a lower yarn feeding speed. False twisting is performed by feeding the yarn at a lower speed than when twisting, as long as the yarn is not lowered, and winding the yarn with a higher yarn feeding speed onto the yarn with a lower yarn feeding speed. The gist of this paper is a method for producing twisted special composite yarn. Hereinafter, the method of the present invention will be explained based on illustrated examples. The figure is a process schematic diagram showing an example of the method of the present invention, in which 2 and 2' are yarn feeding devices, 3 is a heating device,
4 is a twisting device for applying intermittent false twisting, and 5 is a pulling device. The yarn 1 is fed by the yarn feeding device 2, and the yarn 1' is fed by the yarn feeding device 2', and is pulled together before the heating device 3, and then taken off via the heating device 3 and the twisting device 4. It is picked up by device 5. In this case, both yarn 1 and yarn 1' are supplied in a supercharged state, but yarn 1' is supplied at a higher supercharging rate than that of yarn 1, and the yarn is intermittently fed. The yarn feeding speed is increased or decreased in response to the operation of the twisting device 4 that provides false twisting. That is, the feeding speed of yarn 1' is increased during yarn twisting, and the feeding speed is decreased within a range that does not become lower than the feeding speed of yarn 1 when yarn twisting is stopped. To describe the twisting phenomenon when such a special processing operation is performed, first, the yarn 1, which is twisted according to the twisting method in the twisting region during the operation of the twisting device 4,
1' passes through the twisting device 4 as it is without being subjected to the untwisting action by stopping the operation of the twisting device 4, and forms an untwisted portion. While the twisting device 4 is not in operation, the feeding speed of the yarn 1' supplied to the twisting region is reduced compared to when the twisting device 4 is in operation, and is lower, but the supercharging rate is higher than that of the yarn 1. Since yarn 1' is supplied with yarn 1
It is wound by the propagation twist propagated from the untwisted part as if it were being wound. The reason why the feeding speed of the yarn 1' is reduced in response to the stoppage of the operation of the twisting device is due to the transient phenomenon of false twisting due to the intermittent drive of the twisting device and the transient phenomenon of false twisting due to fluctuations in the yarn feeding speed, as described later. This is to synchronize the alternating twists to remain in the yarn at a much higher twist density as a synergistic effect.However, when the yarn stops turning, the amount of twist decreases, and the yarn 1' This prevents the yarn from being over-fed at a high speed, causing sagging, wrapping around the rollers, causing yarn breakage, or inhibiting the yarn twisting action due to the continued operation of the twisting device, and stabilizes the yarn. It has the effect of performing processing. Next, while the twisting device 4 is stopped, the yarns 1 and 1' supplied to the twisting region are subjected to a strong twist by the operation of the twisting device 4, and at the same time, the yarns 1 and 1' are twisted at once in the untwisting region downstream of the twisting device 4. The yarn is untwisted to form an over-untwisted part. In response to the operation of the twisting device 4, the feeding speed of the yarn 1' supplied to the twisting region increases and becomes faster than when the twisting device 4 is stopped, but as a result, the twisting tension decreases. At the same time, the amount of winding of the yarn during twisting is increased, and at the same time, the untwisting action in the untwisting region is performed all at once up to the time of the take-off device 5, thereby forming an over-untwisted portion having a high twist density. Can be done. There is a good reason why the twisting effect of alternate twisting can be greatly enhanced by changing the yarn feeding speed of the yarn on the high supercharging side, where the yarn feeding speed is high, in response to twisting and stopping of the yarn. Although it has not been elucidated yet, it is not only the effect of the increase in the amount of winding of the yarn in the twisting region and the increase in the number of twists when the yarn feeding speed increases, but also the effect of intermittent false twisting in which the twisting of the yarn repeatedly stops and stops. It is possible to synergistically enhance the alternating twist forming action by synchronizing the twisting with the variable speed operation of the yarn feeding speed, which allows alternating twists to be formed in the yarn without intermittent false twisting. It seems possible. In other words, the phenomenon of alternating twist formation is a phenomenon in which the twist in the heating area cancels out the twist in the untwisting area downstream of the twisting device, but the twist that is not completely canceled remains. It is considered that increasing the yarn feeding speed of the yarn on the high supercharging side in response to this makes it even more difficult for twist cancellation to occur. On the other hand, the untwisted part that is formed when the yarn twisting is stopped forms a twisted part where one yarn is tightly wound with the speed increased in the twisting region when the yarn is twisted. The parts are wound up as they are while propagating the twist to the supply side one after another to become a twisted part. At this time, the yarn feeding speed of the yarn on the high supercharging side is decreased, but this is because the yarn feeding speed of the yarn on the high supercharging side increases during the subsequent yarn twisting action, and the yarn twisting is stabilized. This is to spread the propagation twist to the two supplied yarns so that the twisting is carried out in a similar manner. The alternately twisted yarn according to the method of the present invention has a core yarn, which is a low-supercharging side yarn, and a sheath yarn, which is a high-supercharge side yarn, tightly wound. The stability of the alternating twist form due to the application of tension is very good, and the texture is smooth due to the uneven pitch of the wound yarn, and the fiber axis of the sheath yarn is much more inclined with respect to the fiber axis direction of the core yarn. As a result, when made into a fabric, it has a heavy feel,
It has drapability and elasticity, and has a pseudo strong twist effect that enhances the strong twist effect. In the method of the present invention, it is necessary to feed two or more yarns at different yarn feeding speeds, and in order to sufficiently impart a strong twisting effect to the yarns, it is preferable that the yarns differ by 5% or more, particularly preferably. is to have a difference of 8% or more. If the difference in yarn feeding speed is less than 5%, the sheath yarn will not wrap around the core yarn sufficiently and the two yarns will be aligned or close to it, and a pseudo strong twist effect cannot be expected. be. It is preferable that the number of sheath yarns to be wound is as large as possible without changing the winding point at which the sheath yarn winds around the core yarn during yarn twisting. It should be determined by taking into account the twisting time and stopping time. Furthermore, in order to effectively achieve the effects of the present invention,
It is preferable that the range of change in the yarn feeding speed of the sheath yarn is 2% or more. If this range of variation is less than 2%, the variation may be too small to effectively enhance the alternating twist forming effect. The manufacturing principle of the present invention is as described above,
As a specific manufacturing method, the false-twisting device used may be a normal mechanical spindle that rotates and stops, but from the viewpoint of durability and response performance, it is preferable to use a friction false-twisting device or a false-twisting device that uses air swirling flow. It is preferable to use In order to achieve stable processing, especially when the yarn feeding speed is significantly increased in response to yarn twisting, air swirling flow has the function of increasing the amount of yarn twisting by increasing the amount of supercharging. It is preferable to use a twisting device according to. Furthermore, in the present invention, two or more yarns are fed at different yarn feeding speeds, and the yarn feeding speed of the yarn having a high yarn feeding speed is changed in accordance with twisting and stopping of the yarn. The yarn feeding speed of a yarn with a low yarn feeding speed may be changed in accordance with twisting and stopping of the yarn. However, in this case, the rate of increase in the yarn feeding speed during twisting of the yarn with a high yarn feeding speed must be greater than the rate of increase in the yarn feeding speed of the yarn with a low yarn feeding speed.
When a sufficient winding amount of the sheath yarn cannot be obtained and yarn twisting is stopped, the yarn feeding speed of the yarn whose yarn feeding speed is higher than that of the yarn whose yarn feeding speed is low is decreased. If the ratio is not larger, the entire supplied yarn or the yarn fed at a high yarn feeding speed will become slack, causing winding around the rollers and causing yarn breakage or inhibiting the continued yarn twisting action. Only alternately twisted yarns with extremely low twist density can be obtained. As the yarn supply device used in the present invention, a supply roller having a function of changing the rotation speed of the supply roller in response to twisting and stopping of the yarn, or a passive roller that rotates due to yarn running tension is used. The present invention includes the use of a yarn feeding device that varies the yarn feeding speed by changing the load resistance of the rotating body to a light load or a heavy load in response to twisting and stopping of the yarn. Any material may be used as long as it satisfies the manufacturing principle. As the yarn to be supplied in the present invention, drawn yarn, semi-drawn yarn, or undrawn yarn of thermoplastic synthetic fiber multifilament yarn such as polyester or polyamide can be used. It is also possible to use processed yarn. These yarns are usually a composite of the same type of yarn, but depending on the purpose and use, it is also possible to use a combination of yarns with different polymers, different stretching conditions, or different types of yarns with or without crimping. . In the above description, the case where two or more thermoplastic multifilaments are supplied in a supercharged state is mainly shown, but the supply rate may be 0 or negative. In the method of the present invention, since the above-described configuration is adopted, it is possible to obtain a highly twisted composite yarn having an extremely high high twisting effect in which the sheath yarn is wound around the core yarn. Since the yarn feeding speed of the yarn with a higher yarn feeding speed among two or more thermoplastic multifilament yarns is changed in response to intermittent false twisting, alternating twisting of untwisted portions and overtwisted portions can be avoided. It is able to remain at a high density, increase the amount of winding of the sheath yarn and increase the number of twists, and also prevents the yarn from sagging and wrapping around the rollers during the production of composite yarn. It is possible to obtain a composite yarn with a strong twist. The present invention will be specifically explained below using examples. Example 1 Polyester filament 50D/24F (circular cross-section ply yarn; hereinafter referred to as yarn A) and polyester filament 100D/36F (circular cross-section ply yarn; hereinafter referred to as yarn B) were heated and false-twisted using different variable speed rollers. The yarn is guided into a false twisting zone consisting of a device and a delivery roller, and processed under the processing conditions of intermittent false twisting using an air swirl flow shown in Table 1, to produce a highly twisted special composite yarn with the number of twists shown in Table 2. Obtained. The fluid supply and stop times are set by commands from a microcomputer into which a random signal has been input in advance.
A time of 0.3 seconds was used randomly.

【table】

【table】

[Table] This highly twisted special composite yarn has a warp density of 78 pieces/inch.
When weaved into a plain weave structure with a weft density of 66 threads/inch, subjected to a 15% alkali reduction process, and then finished with polyester dyeing, we achieved a silkiness, drapability, and weight that could never be achieved with conventional alternately twisted yarns. A highly twisted fabric with good feel and elasticity was obtained. Example 2 Two polyester filaments 50D/24F (bright yarn with triangular cross section) were used, each with a feeder whose load could be electromagnetically varied, a heating plate, a twisting device using air swirling flow, and a first delivery roller. , a second heater that performs relaxation heat treatment;
Processing was performed under the processing conditions of intermittent false twisting shown in Table 3 in a processing step consisting of a delivery roller and a winding device, to obtain a highly twisted special composite yarn having the number of twists shown in Table 4. The fluid supply and stop times were set at random times of 0.9 to 0.3 seconds for both supply and stop times based on commands from a microcomputer into which random signals had been input in advance.

【table】

【table】

[Table] When the obtained high-twist yarn-like special composite yarn was knitted into a Motsuku Milano rib structure using 22-gauge double knit and subjected to ordinary polyester dyeing and finishing processing, a high-twist yarn-like knitted fabric was obtained, which was not seen in conventional alternately twisted yarns. was gotten.

[Brief explanation of the drawing]

The drawings are process schematic diagrams showing an example of the method for producing processed yarn of the present invention. 1, 1'... supply yarn, 2... constant speed supply roller,
2'...Variable speed roller, 3...Heater, 4...False twisting device, 5...Delivery roller.

Claims (1)

[Claims] 1. When false-twisting two or more thermoplastic multifilament yarns intermittently by repeatedly twisting and stopping twisting, the two or more thermoplastic multifilament yarns are fed at different yarn feeding speeds. At the same time, the yarn with a higher yarn feeding speed is increased during yarn twisting in response to intermittent false twisting, and the yarn feeding speed of the yarn with a lower yarn feeding speed is increased when yarn twisting is stopped. False twisting is performed by supplying the yarn at a lower speed than that during yarn twisting within a range that does not lower the yarn feeding speed, and winding the yarn with a higher yarn feeding speed onto the yarn with a lower yarn feeding speed. A method for producing a special composite yarn with strong twist characteristics. 2. The two thermoplastic multifilament yarns are fed at yarn feeding speeds that differ by 5% or more, and the yarn feeding speed of the yarn with the larger yarn feeding speed is set at the time of yarn twisting and at the time of yarn twisting stop. The method for producing a highly twisted special composite yarn according to claim 1, wherein false twisting is performed with a variation width of 2% or more.