JPH0341587B2 - - Google Patents

Description

[Detailed description of the invention]

Conventionally, skein dyeing has been used as a method for dyeing false twisted yarn in a highly crimped state, but this method has been considered to have the drawbacks of complicated processes and high processing costs. The present invention solves this drawback and provides a method and apparatus for producing highly elastic yarn-dyed yarn with crimp comparable to skein dyeing using a simple method of directly dyeing a cheese-like package rolled up on a false twisting machine. The purpose is to provide. The general processing steps for skein dyeing are (1) Two or more false twisted yarns with different twist directions are wound into a package in a aligned state. (2) Combine and twist the aligned false twisted yarns. (3) Wind the twisted yarn into a skein. (4) Release the skeins and develop crimp. (5) Dye and dry while still in the crimp state. (6) Stretch the contracted skein and set it on the skein wheel. (7) Re-roll it into a package such as a cone. This process requires a complicated process, and if false-twisted yarn-dyed yarn with crimps comparable to skein dyeing could be obtained by directly dyeing the cheese-like package rolled up on a false-twisting machine, it would be a huge streamlining process. It is. In the case of skein dyeing,
This method dyes the skein after winding the yarn, causing the skein to contract and develop crimps.However, in the method of directly dyeing the package obtained on a false twisting machine, the yarn must be sufficiently relaxed before winding. If the yarn is wound at a high feed rate comparable to the contraction of skein, it becomes possible to dye the yarn in a crimp development state similar to that of skein dyeing, and it is possible to obtain yarn-dyed yarn with high elasticity comparable to skein dyeing. However, simply winding the false twisted yarn at a high feed rate will cause the single filaments of adjacent yarns to become entangled when the yarn is unwound from the dyed package cage in the rewinding process such as cone winding after dyeing.
Due to the frequent occurrence of yarn breakage, the winding feed has been limited to +50% in terms of productivity. This problem in the rewinding process can be solved by subjecting the yarn to a convergence treatment to improve unwinding properties, and in Japanese Patent Application Laid-Open No. 52-55761, the yarn is subjected to an interlacing treatment to improve the unwinding property. A method and apparatus for producing a highly elastic yarn-dyed yarn has been proposed in which the yarn is wound with an overfeed of +70 to 100% and the package is dyed. However, the crimp of the yarn produced by this proposal has an expansion/contraction recovery rate of about 30%, which is extremely insufficient compared to the crimp of skein dyeing (expansion/contraction recovery rate of about 45%) aimed at by the present inventor. The reason for this is that the interlacing process performed as a means of converging the yarn inhibits the relaxing contraction of the yarn, so the winding feed is
This is because 100% is the limit and it is impossible to wind with a high feed comparable to the shrinkage of the skein. That is, in order to directly dye a package by winding up highly elastic yarn-dyed yarn on a false-twisting machine and directly dyeing the package, which is the aim of the present inventors, it is necessary to wind the false-twisted yarn around the package. When taking the skein, (1) Take it up at a high feed rate comparable to the contraction of the skein. (2) The yarn is subjected to a focusing process sufficient to release the yarn in the rewinding process. (3) The yarn convergence treatment in (2) must not impede contraction and crimp of the yarn. The following conditions must be met. That is, the present invention provides a method for dyeing false twisted yarn in a cheese-like package, in order to satisfy the above three conditions when winding the yarn into a package on a false twisting machine, the yarn can be crimped without inhibiting shrinkage and crimping of the yarn. It has crimps comparable to the skein obtained by winding the bundled yarn in an alternately twisted spiral form in its developed state at a high feed of about 100% to 300%, dyeing it in this package state, and rewinding it. The present invention provides a method and apparatus for producing highly elastic yarn-dyed yarn. The present invention will be explained in more detail below with reference to the drawings. FIG. 1 is a schematic diagram of an apparatus for producing highly elastic yarn-dyed yarn of the present invention. The thermoplastic synthetic fiber yarn 1 is alternately twisted while maintaining the crimped state before the winding device 6 of a normal one-heater false twisting machine consisting of a feed roller 2, a heater 3, a spindle 4, and a delivery roller 5. As shown in Fig. 2, it performs a spiral-type convergence process and has a yarn conveying effect to send the yarn to the winding device 6 without being wound around the delivery roller 5 even if the winding device is set at a high feed rate. It is equipped with an air jet 7 having a structure that releases the false-twisted yarn from the package and brings it into a good convergence state.
It has the ability to wind into a package cage with a high feed of about 300%. As shown in Fig. 2, the structure of the air jet 7 consists of a thread guide hole 8 and an air injection hole 9 which is opened at an angle α of 45° or less at a position eccentric to the thread guide hole 8. The air blown into the hole 8 flows in the yarn running direction while swirling inside the yarn guide hole 8, and is discharged from the air jet 7 toward the winding device. The false twisted yarn sent out from the delivery roller is sucked into the air seat 7, and then blown out toward the winding device by the swirling air current, and is wound up in a winding device rotating at low speed with sufficient crimp development without tension. It will be done. That is, due to the yarn conveying effect of the airflow, tension is applied to the yarn in front of the jet so that it does not wrap around the delivery roller, and after passing through the jet, the yarn becomes tensionless and crimps occur. At this time, the direction of rotation of the swirling airflow is opposite to the rotation of the false twisting spindle, that is, the direction opposite to the torque generated in the yarn due to false twisting. Alternatively, if the twist is stopped just before the twisting (by bending the yarn at the jet inlet as shown in Figure 2), the yarn will cause a whirling motion with the airflow inside the jet thread guide hole 8, and when it leaves the jet, it will be inside the yarn. As shown in Figure 3, the single fibers are loosely intertwined with each other in a spiral shape, and at the same time, the entire yarn remains in a crimped state as shown in Figure 4.
Gentle S and Z twists of about 300T/M
A uniform convergence state of alternate twists mixed at intervals of 10 to 30 cm can be obtained. If the direction of rotation of the swirling airflow is the same as the direction of rotation of the false twisting spindle, the yarn will be given a strong alternating twist with a large number of twists, and the yarn will not be able to be wound up in a crimped state. Furthermore, if the twist stop at the jet inlet is insufficient, the state in which the alternate twists are generated becomes unstable, and snarl nep etc. occur in parts where the number of twists is large, making it difficult to obtain a uniform state of convergence of the alternate twists. Highly elastic yarn-dyed yarn can be obtained by dyeing and drying the false-twisted yarn package that has been sufficiently crimped and wound in a uniformly bundled state, and then rewinding it by cone winding or the like. However, the higher the winding feed is set, the higher the crimp of the yarn can be obtained.It varies slightly depending on the type of yarn, but the crimp of the yarn is higher than the winding feed +200 to 250.
%, it is possible to obtain the same crimp as conventional skein-dyed yarn. Furthermore, the yarn breakage during rewinding, which has been the biggest obstacle to the practical application of this type of processing method, can be avoided even though winding is performed at such a high feed rate due to the focusing effect given to the yarn. The amount is very small and the workability is good. Note that the bundled form of the yarn is destroyed by the tension applied during rewinding, and the final appearance is similar to that of ordinary one-heater false twisted yarn. In other words, in the present invention, the false-twisted yarn is bundled while it is in a sufficiently crimped state, dyed as a package, and then re-wound.The workability is good and the process is simple. The present invention provides a method for processing a false-twisted dyed yarn having crimps. The fibers used in this invention can generally be any thermoplastic fibers that can be subjected to false twist and crimp processing. Furthermore, the processing method is not limited to single thread processing, but it is also possible to wind two or more false twisted threads with different twist directions through an air jet and dye them. The yarn obtained by this drawing process becomes a non-torque yarn similar to a conventional double thread skein dyed yarn by canceling out the conflicting torques of each yarn. At this time, the rotating direction of the air jet may be either SZ or SZ, and a uniform convergence state can be obtained. Note that the structure of the air jet used in the present invention is not limited to that shown in FIG. 2, but may be any structure that can generate a swirling airflow flowing toward the winding device, and the installation position of the jet may also be changed. If it is in a position in front of the winding device where the focusing process can be performed while the crimp is still developing, the first
It is not limited to the position shown in the figure. Example 1 Raw yarn of polyester 150 denier 30 filament was false twisted using a processing machine having the structure as shown in Fig. 1 at a heater temperature of 210°C and a false twist number of 2500 T/M (Z twisting) processing feed of 0%. The yarn was wound around cheese with an overfeed of +267% through an air jet having the structure shown in the figure, dyed using a conventional cheese dyeing machine, and then re-wound using a cone winding machine to obtain a highly elastic yarn-dyed yarn. At that time, thread breakage in the cone winding process was 1.0Kg/
There was no yarn breakage with cheese, and workability was good, and the crimp property values of the obtained yarn had sufficient significance as shown in the table below when compared with those of yarn dyed under the same false-twisting conditions. .

[Table] Example 2 A polyamide yarn of 70 denier and 24 filaments was processed in the same manner as in Example 1 at a heater temperature of 175°C.
Number of false twists: 2950T/M (Z-twisting) Processing feed: 3%
As a result of winding, dyeing, and cone winding into false twisted cheese at a winding feed of +267%, the crimp property values were as shown in the following table, with no yarn breakage when cone winding was carried out at 1.4 kg/cheese.

【table】 [Brief explanation of drawings]

FIG. 1 is a schematic diagram of the apparatus of the present invention. FIGS. 2A and 2B are schematic diagrams showing an example of an air jet used in the present invention. FIGS. 3 and 4 are diagrams showing the form of the yarn after passing through the air jet of the present invention. 7... Air jet, 8... Thread guide hole, 9... Air injection hole.

Claims (1)

[Scope of Claims] 1. In a package dyeing method in which false-twisted yarn is dyed in the state of a wound package, after false-twisting and before winding, an air jet having a yarn conveying action and a swirling action is used in an overfeed state of more than 100%. 1. A method for producing a highly stretchable yarn-dyed yarn, which comprises applying alternating twists to the false-twisted yarn, winding the false-twisted yarn in the form of an alternately twisted yarn, and then dyeing the wound package in the package state. 2. The method for producing highly elastic yarn-dyed yarn according to claim 1, wherein the yarn is wound in an overfeed state of more than 100% and less than 300%. 3 An overfeed area exceeding 100% is set in front of the winding device of the 1-heater false twisting machine, which consists of a feed roller, a heater, a false twisting device, and a delivery roller, and the yarn flows in the yarn running direction in the overfeed area. A highly elastic yarn-dyed yarn production device characterized by being equipped with an air jet that generates swirling airflow.