JPS6039772B2 - Method for manufacturing crimped yarn - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for manufacturing box silk yarn.

More specifically, it relates to an improvement in a method for producing a wound yarn in which undrawn or semi-drawn yarn made of thermoplastic synthetic fiber filaments is false-twisted simultaneously or sequentially with stretching, and then modified set. It is something.

BACKGROUND ART Conventionally, as one of the final finishing treatments for textiles, a method of calendering is known for the purpose of improving the texture or adding luster.

In addition, as a technique similar to this method, in the processing of general fiber threads, the threads are fed to a hard pressure roller and passed through, thereby flattening the cross section of the single fibers, leaving marks on the side surfaces of the fibers, etc. There are known techniques for making the constituent single fibers irregular, improving drapability, surface light selection, and touch, and making the woofer yarn non-torque.
These yarns have been used for woven and knitted fabrics. For example, Japanese Patent Publication No. 50-3559y discloses that the multifilament fibers are fed between unheated pressure curing rollers in a state in which all the single fibers are intertwined and passed through two or more times. Accordingly, a method has been proposed in which random groove-like traces are formed by the intersecting portions on the longitudinal side of a single fiber to obtain silk-like light selection, touch, and texture.

Furthermore, in Japanese Patent Application Laid-Open No. 49-754, a thermoplastic synthetic fiber multifilament yarn is continuously passed between hard rollers after the false twisting process to make winding stripes latent, and then the yarn is twisted. A method has been proposed in which a low-torque bulky textured yarn is obtained by heat-treating the yarn in a relaxed state. What these methods all have in common is that a thermoplastic synthetic fiber thread at room temperature is passed between hard pressure rollers. However, when attempting to impart permanent deformation to woolly yarn obtained using ordinary drawn yarn by passing it through a hard pressure roller at room temperature, it is not under a thermoplastic state, and Since the material used is a yarn with a high Young's modulus that has been sufficiently drawn, it must be passed through many hard rollers under fairly high pressure, which induces destruction of the molecular structure of the yarn. Even if it is possible to create irregularities in the sides and cross section of a single fiber, the elasticity may be lost or
The disadvantage is that extreme traces or single fiber breaks (fluff) occur. In other words, when a woolly yarn made of ordinary drawn yarn at room temperature is passed through a hard pressure roller, the elasticity is lost, resulting in a decrease in crimp development force.
Also, since extreme traces increase the frictional resistance between threads,
As a result, various inconveniences have occurred, such as a voluminous feel, a decrease in winding strength, a squeaky feeling, and a decrease in operability. An object of the present invention is to employ a particularly hard pressure roller in the process of producing a crimped yarn, in which undrawn yarn or semi-drawn yarn made of thermoplastic synthetic fibers is false-twisted simultaneously or sequentially with stretching. However, without the various disadvantages that occur in the conventional method using hard pressure rollers as described above, it is possible to use the method in particular by combining the stretch false twisting process with the use of the rollers. It is an object of the present invention to provide a method for producing a crimped yarn that makes it possible to obtain a more preferable and improved crimped yarn.

For this purpose, an undrawn yarn or a semi-drawn yarn made of thermoplastic synthetic fiber filaments is subjected to a drawing false twisting process and a modify setting, and then the processed yarn in a thermoplastic state immediately after the modify setting is subjected to hard pressure. This is achieved by a method for producing a crimped yarn characterized by supplying the yarn to a roller member and causing it to pass through, thereby making the side surfaces and cross sections of the constituent fibers irregular. Hereinafter, the method for producing a crimped yarn of the present invention will be explained in more detail based on the drawings.

FIG. 1 is a process schematic diagram showing one example of the method for manufacturing a crimped yarn of the present invention, and shows a process of performing false twisting simultaneously with stretching.

In FIG. 1, an undrawn multifilament yarn or a semi-drawn multifilament yarn 1 is supplied to a drawing roller 2 of a two-heater type drawing false twisting machine, twisted by a false twisting spindle 4, and heat set by a primary heater 3. After being cooled, it is decombusted, and while being taken up by the delivery lo-fu 5, normal stretching and simultaneous false twisting is carried out.

Next, while relaxing between the relaxing roller 8 and the delivery roller 5, a normal modify setting is performed by a secondary heater 6. Immediately after the modify setting, the processed yarn is supplied to a hard pressure roller 7 and passed through. The product is packaged by the winding roller 9 directly from the relaxation roller 8 or from the pressure roller 7. The method for producing crimped yarn of the invention takes the steps described above, but the particularly important requirements are: (1) Use of undrawn yarn or semi-undrawn yarn of thermoplastic synthetic fiber such as polyester or polyamide as the supplied yarn. (1) The position at which the hard pressure roller is passed should be immediately after the modification set.

That is, it is essential that the position where the processed yarn is supplied to and passed through the hard pressure roller member be applied immediately after modification setting.

This is because the woolly yarn is reheated and set in a modify set heater (secondary heater), but immediately after leaving the setting castle, the woolly yarn remains in a thermoplastic state and is simultaneously deformed by a hardening pressure roller. This is because the sides and cross section of the single fiber can be made irregular very easily and smoothly. moreover,
As a factor governing the degree of irregularity in the side surfaces and cross-sections of single fibers caused by the hard pressure roller, it goes without saying that it is desirable that the material be easily deformed by the pressure roller when viewed from the perspective of the supplied yarn. However, even if the same material is used, there are undrawn yarns than drawn yarns, and semi-drawn yarns are particularly effective in imparting deformation by the pressure roller. This is because the degree of cross-sectional deformation of the side surface of the curly yarn due to the drawing simultaneous false-twisting process or the drawing sequential false-twisting process of undrawn yarn or semi-drawn yarn is due to the shape when false twisting is performed using drawn yarn as the supplied yarn. Due to the fact that it is much larger than the degree,
According to the method of the present invention, the twisted yarn having a large degree of deformation due to drawing false twisting is supplied to the hard pressure roller member immediately after modify setting, that is, in a thermoplasticized state. Furthermore, a crimped yarn with a large deformation effect can be obtained extremely easily.
In addition, due to stretching and false twisting, the fiber cross section tends to become flattened and irregular, and as mentioned above, it is highly deformed. It will be full of variety.

Furthermore, according to the method for producing a crimped yarn of the present invention, it is possible to easily obtain a crimped yarn in which the constituent single fibers are irregular as described above. It has excellent properties such as a relatively small decrease in the number of twists and an extremely small residual torque twist number.

In particular, due to the high deformation and strong indentation caused by false twisting, the number of residual torque twists is greatly reduced. This is at a level that cannot be achieved even if a drawn yarn using a similar yarn is used as a starting yarn and subjected to false twisting, modification, and hard pressure roller treatment. This also has the effect that since the torque of the monofilament filaments is reduced, the monofilaments are more likely to be parallel and more glossy. Conventionally, it has been difficult to control both the expansion/contraction recovery ratio and the residual torque twist number, but according to the method of the present invention, both of these characteristics can be easily controlled, and both characteristics are excellent. A crimped yarn having the following properties is obtained. Although the details of the cause of this are not clear, the secondary heater applies heat under a certain relaxation length to adjust the crimp characteristics of the processed yarn, but the movement of the yarn running on the heater tends to rotate freely due to the influence of residual torque, and torque is generally difficult to fix and adjustment is difficult.

On the other hand, a hard pressure roller is a set that fixes the movement of the yarn under constant pressure and deforms the fiber side surface and cross section, and can easily eliminate residual torque. Difficult to adjust. When attempting to control both crimp characteristics and residual torque, it is possible to appropriately change the setting conditions (temperature, relaxation rate, etc.) of the secondary heater without using a hard pressure roller, or to change the settings of the secondary heater. It is possible to consider measures such as installing a hard pressurized roller at the front, but in the former case, a high heater temperature is required to control the residual torque, and in that case, the crimp characteristics may be impaired. Furthermore, in the case of the latter method, as mentioned above, it is necessary to set a high hard roller pressure to pressurize and deform the fibers at room temperature, and in that case, the resulting yarn may have a "squeaky" feel. , it tends to have a "paper-like feel".
Therefore, when trying to control both box shrinkage characteristics and residual torque, it is essential to use both a hard pressure roller as a secondary heater.
In particular, by supplying the yarn to the hard pressure roller immediately after passing through the secondary heater, the residual torque due to the pressure loaf can be easily reduced because it is in a thermoplastic state. The gripping force of the pressure roller makes it possible to prevent the yarn from moving more than necessary in the secondary heater, increasing the efficiency of heat setting in the secondary heater, and making it extremely easy to control both characteristics. In this way, by providing a secondary heater and a hard pressure roller, especially by providing a hard pressure roller immediately after the secondary heater, it is possible to set both sets advantageously, making it possible to create a modified set. This creates a synergistic effect. The method for producing a wound striped yarn of the present invention is applicable not only to multifilament yarns, monofilament yarns, but also to cases where monofilament yarns are used as supply yarns.

In addition, in the method for producing crimped yarn of the present invention, there is no need to set special conditions for the processing conditions of the drawing simultaneous false-twisting process, the drawing sequential false-twisting process, or the modify setting process, and the processing conditions can be set within the normal setting range. is sufficient.
When looking at the supplied yarn, it is preferable to use a material that is easily deformed by a hard pressure roller, and a material with a low Young's modulus is desirable.Furthermore, yarns with irregular cross sections are more easily deformed than those with round cross sections, and the present invention The effects of this method are noticeable. Regarding the draw false-twisting process, a method in which the deformation rate of the side surfaces and cross-sections of the yarn is large and the Young's modulus is low is suitable, so the simultaneous draw and false-twisting process of the present invention is better than the draw-sequential false-twisting process. The effect becomes more noticeable. Furthermore, regarding the pre-combustion conditions, it is preferable that the lower the false-twist draw ratio and the greater the number of false twists, the higher the deformation rate as a woolly yarn and the easier it is to undergo pressurized deformation. The hard pressure roller is normally provided at a position within 50 mm downstream of the end face of the secondary heater, preferably within 30 mm downstream from the end face of the secondary heater.

The pressurization. The material of the roller is preferably steel, aluminum, Bakelite, etc., and hard rubber is not so preferable because it tends to lack hardness. The number of hard pressure rollers may be a pair of rollers as shown in FIG.
Alternatively, a plurality of pairs of rollers may be used. Furthermore, the yarn may be wound around a single roller over a plurality of pairs, but increasing the number of times of winding causes a decrease in the pressing force, so it is preferable not to increase the number of times of winding too much. In the method for producing wound warp yarns of the present invention, the yarn is cooled after leaving such a hard pressure roller, but this cooling is performed for the purpose of fixing the deformation of the single fiber side surface and cross section caused by the pressure roller. Therefore, there is no need to employ any special cooling means, and natural cooling at room temperature is sufficient. An example of the shape of the single fiber side surface and cross section of the twisted yarn obtained by the production method of the present invention will be explained with reference to FIG. The cross section of the trace portion is rounded and flattened.

Figure a shows a schematic side view of the exterior of the single line, showing the traces of the Ichikawa Mahekomi, and figure b is a cross-sectional view of the part (
(A-A cross section in figure a). According to the above-described method for producing twisted yarn of the present invention, it is extremely simple in terms of equipment, does not involve a decrease in processing speed or deterioration of operability, and furthermore does not involve any destruction of the molecular structure. It is extremely easy to obtain a crimped yarn in which the side surfaces and cross-sections of the constituent fibers are made irregular, and the yarn properties are also excellent.

Hereinafter, the specific structure and effects of the method for producing crimped yarn of the present invention will be further explained according to Examples.

Example polyester undrawn yarn 150 denier (after stretching) 48
Using a round cross-section filament yarn, the number of false twists was 2360 using a two-heater type drawing false twisting machine as schematically shown in Fig. 1.
Tnom, set temperature 21000, false twisting at the same time as stretching at a false twisting stretching ratio of 1.8 times, then modify setting temperature 20
000. Immediately after modification processing with a relaxation rate of +16%, a pressure of 3.5k9 was applied to a hard metal (steel) roller, the yarn was passed through the roller 5 times in succession, and the yarn was wound around cheese with an overfeed rate of -5%. I got it.

The degree of cross-sectional deformation of the twisted yarn is 29.4%, and the expansion/contraction recovery rate is 14.
．． 1%, and the residual torque twist number was 7.4. As a result of knitting into 28G jersey using this winding warp and dyeing and finishing,
Compared to threads made using striped threads obtained by methods that do not use hard pressure rollers, this yarn has excellent drapeability, softness, sliminess, etc., and eliminates the ``squeaky'' feeling of cake flour. A product with a mild texture was obtained.

As Comparative Example 1, a polyester drawn yarn of 150 denier and 48 filaments with a round cross section was wound using a normal two-heater type false twisting machine with a false twist feed rate of +2% and the other conditions being the same as in the above example. A shrunken yarn was obtained.

The degree of cross-sectional deformation of this crimped yarn is 12.3%, and the expansion/recovery rate is 1
6.8%, and the residual torque fuel number was 18.0. As a result of evaluating the crimped yarn after knitting and dyeing it in the same manner as in the above examples, it was not possible to obtain a yarn with a mild texture like that obtained by the method of the present invention. Further, as Comparative Example 2, a wound striped yarn was obtained using the same supplied material as in the above example and under the same processing conditions except that the yarn was not passed through a hard pressure roller.

The degree of cross-sectional deformation of this crimped yarn is 18.6%, and the elasticity recovery rate is 2.
5.0%, and the residual torque twist number was 38. As shown in Fig. 3, the degree of cross-sectional deformation is determined by determining the length 1 of the longest diagonal line and the length 12 of the shortest diagonal line in the cross section of the dented portion of the single fiber, and calculating the degree of cross-sectional deformation using the following formula m. This is the average value measured at 30 random locations. Cross-sectional deformation Y%): (1-Harm)X・〇. ---
‐‐‐‐‐...‐‐{1} The expansion and contraction recovery rate is JiS (LIO9
It is based on the measurement method of 0-70), and the quality is 10
A value of ~13% is most preferable in terms of crimp characteristics in terms of waist tension and bulk, and the number of residual torque twists is as follows: Take a lm-long sample, fold it in half, and then The number of rotations was measured by suspending a load, and the lower the number of rotations, the less residual torque, which is preferable in terms of drapability, "surface" and touch.

[Brief explanation of drawings]

FIG. 1 is a process schematic diagram showing one example of the method for producing a winding yarn of the present invention. FIG. 2 is a schematic diagram showing the shape of the monofilament paper side and cross section of the crimped yarn obtained by the manufacturing method of the present invention, FIG. 2 a is a schematic diagram of the external appearance, and FIG. FIG. 3 is an explanatory diagram for determining the degree of cross-sectional deformation of fibers. 1: Undrawn yarn or semi-drawn yarn, 2: Stretched lo-fu, 3: Primary heater, 4: False twist spindle, 5: Delivery. - Fu -, 6: Secondary heater, 7: Hard pressurized low fu,
8: Relax loaf, 9: Roll up loaf, 10:
Traces of dents. Figure 2 is 3

Claims (1)

[Claims] 1. An undrawn yarn or a semi-undrawn yarn made of a thermoplastic synthetic fiber filament is subjected to drawing false twisting and modification setting, and then the processed yarn, which is in a thermoplastic state immediately after the modification setting, is subjected to hard pressure. A method for producing a crimped yarn, which comprises supplying the fibers to a roller member and causing the fibers to pass through the roller member to make the side surfaces and cross sections of the constituent fibers irregular.