JPS6113014B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a highly twisted textured yarn and a method for producing the same. Recently, many proposals have been made to use continuous untwisted fused yarn (hereinafter simply referred to as fused yarn), in which yarns are fused during the false twisting process, as a means of giving woven and knitted fabrics a crisp, ``grained'' feel. There is. (For example, Tokko Akira
No. 47-49457, Special Publication No. 1972-25065, Special Publication No. 1971-
225, JP-A No. 48-50050), these fused yarns are obtained by false twisting, so they have a high degree of torque, and in terms of yarn use, they are free from frizz, snarls, etc. This results in a decrease in weaving properties. In order to reduce the torque peculiar to such false-twisted yarns, so-called secondary treatment, in which the yarn is further heat-treated in a 10 to 20% relaxed state, has been known for a long time. The present inventors also applied secondary treatment to the fused yarn in order to improve the knitting and weaving properties of the fused yarn in accordance with the conventional proposal. At the same time, I learned that it looked bad and could not be put to practical use. The application of the false twisting process to the fused yarn to give it a "grained" and silky appearance is in a commercially extremely advantageous position in terms of texture and processing speed compared to the use of highly twisted yarns using conventional twisting machines. From this point of view, there is a strong desire to convert to practical woven and knitted fabrics using fused yarns. It is therefore an object of the present invention to eliminate the aforementioned obstacles and to
To provide a fusible yarn and a method for producing the same, which improves weaving properties and provides a knitted fabric with a beautiful surface and no sink marks during knitting. In the course of various studies aimed at achieving the above object, the present inventors discovered that the physical properties of the fused yarn itself, especially the
There is a close relationship between secondary yield strength and sink marks during knitting, and at the same time, the 10~
It was discovered that a 20% relaxation heat treatment tends to cause sink marks during knitting, and as a result of further investigation, the present invention was arrived at. That is, according to the present invention, (1) the filament yarn is made of a single material, there is no substantial difference in yarn length between the filaments, and the yarn as a whole is continuous in a state of being twisted alternately in the S direction and the Z direction; are fused together to give a focused appearance,
A highly twisted textured yarn characterized by having a torque of 50 times/US or less and a primary yield strength of 0.5 g/de or more; After false twisting and crimp processing to produce a continuous fused state in the direction, a secondary relaxation heat treatment is performed, and 2%
Provided is a method for producing a highly twisted textured yarn, which is characterized in that heat treatment is performed under an overfeed of ~7%. Furthermore, regarding this, in the knitting process using processed yarn, the knitting tension is generally 50
A tension of around 60 g/100 de is generated, but if the fed yarn is suddenly stretched under such tension, sink marks will occur in the resulting knitted fabric. Specifically, in the case of knitted fabrics using textured yarns obtained by further heat treatment under overfeed of 10% or more after false twisting and fusing, sink marks are noticeable and at the same time, the eyes are also deteriorated. For this, the overfeed rate is set to 2
The above-mentioned defects are not observed in the fused yarn obtained by heat treatment while maintaining the concentration at ~7%. FIG. 1 shows the strength and elongation curves of the false-twisted fused yarns due to such differences in overfeed ratio. In the figure, a indicates an overfeed rate of 4%, and b
is the strength and elongation curve of a false-twisted fused yarn heat-treated under 15% overfeed during normal wooly processing. Comparing the two, it can be seen that the lower the overfeed rate, the more rapid the rise behavior. The strength at the yield points a′ and b′ is the tension at the time of knitting, that is, 50 to 60
If the value is higher than g/100 de, sink marks will not occur in knitted fabrics, and the eye surface will be further improved.
For this reason, in the present invention, if the primary yield strength of the false twisted fused yarn is at least 0.5 g/de,
It was discovered that the desired knitted fabric could be obtained. Here, the false twisting conditions other than the overfeed rate are as follows. A Raw yarn POY (partially oriented yarn) 110de/36fils B False twist number 2300t/m C Heater temperature 240℃ D Primary overfeed amount -30% E Secondary heater Hollow pipe heater with a diameter of 0.3 cm and a length of 60 cm Heating temperature: 240°C Processing speed: 86 m/min Processing machine: Teijin Seiki FW / US or less. 50 times/
False-twisted fusible yarns having a residual torque exceeding that of rice tend to cause creases and snarls during knitting and weaving, which not only lowers the knitting and weaving properties but also makes it difficult to obtain knitted fabrics that are truly free from sink marks during knitting. The false twisted fused yarn in the present invention has a primary yield strength of 0.5 g/de or more and 50
It is necessary to have a residual torque of less than 100 twists/m2, and a false-twisted fused yarn having such characteristics can be obtained by setting the overfeed rate during the secondary relaxation treatment to 3 to 7%. As the overfeed rate decreases, the eye surface of the resulting knitted fabric tends to improve; however, when the overfeed rate decreases below 3%, the knitted fabric becomes filament-like, with its flexibility and bulk significantly reduced. On the other hand, the overfeed rate is 7%
If this value is exceeded, the eye surface itself will no longer be satisfactory in terms of practicality. The characteristics of the fused yarn of the present invention are as follows when compared to similar technologies. For example, in the method of Example 1 of JP-A-51-136952, a two-layered fusible yarn is proposed (the thickness of the core is 1/3 of the entire yarn). In Example 1, since secondary heat treatment was not performed, the torque was approximately 83 times/US (primary heat treatment: approx.
On the other hand, in Example 2 in which the secondary heat treatment is performed under 15% overfeed, the yield point is significantly lower to about 0.12 g/de. Also, Tokukai Akira
No. 52-5351 discloses that a low melting point yarn and a high melting point yarn are false-twisted and then subjected to a secondary heat treatment (Table 1). The relationship between overfeed and torque or primary yield strength in this case is as follows.

[Table] *No secondary heat treatment Furthermore, although Japanese Patent Publication No. 1983-47972 indicates that the yarn is forcibly vibrated on a heater in the false twist fusion process (secondary heat treatment is not indicated), In this case, it is a so-called single heater system, so it is inevitable that the torque will exceed 100. Further, Japanese Patent Publication No. 56-43133 discloses a false-twisted fusible yarn that is composed of two or more types of yarns with different softening points and dyeability, and has a fused portion and a crimp portion. In this case, the overfeed amount during secondary heat treatment is 15%, so the primary yield strength is approximately 0.3 g/
It decreases to around de. FIG. 2 shows an example of the manufacturing process of the false twist fused yarn of the present invention, in which the raw yarn 1 is pulled out from the cheese 2, passes through the guide 3, and is supplied from the supply roller 4 to the false twist crimping processing zone. . In this zone, the yarn 1 is first given a false twist by the false twister 5, which is then heat-set on a heater 6 heated to 225°C to 255°C, and then untwisted by the false twister 5 and later. be done. The yarn thus obtained is an untwisted continuous fused yarn 8 in which the constituent filaments are fused to each other and has a strong so-called torque and exhibits alternating S and Z-shaped twists along the yarn axis direction.
This fused yarn is sent from the intermediate roller 7 to the hollow pipe heater 11, where it is subjected to relaxation heat treatment under an overfeed amount of 2% to 7%, and then passed through the delivery roller 12 to a bobbin driven by the friction roller 9. It is wound up to 10. The raw yarn 1 used in the present invention may be a filament yarn made of a single material, that is, a yarn made of the same polymer and with no substantial difference in strength and elongation between filaments, preferably polyester. Filament yarns of the same type are advantageously used. As the polyester filament yarn, in addition to the polyester filament yarn that has been normally drawn and heat treated, POY (Pre-Oriented Yarn), which has recently been put into practical use, can also be preferably used. When processing this POY, between the supply roller 4 and the intermediate roller 7, the yarn is several 10%
Processed to be stretched. On the other hand, the degree of heating of the hollow pipe heater is an important factor as it affects the torque and primary yield strength of the yarn finally obtained, but generally the ambient temperature is 230 to 255.
It is adopted in the range of about ℃. Note that the above overfeed amount is based on the intermediate roller 7.
The peripheral speed of the delivery roller 12 is V ₁ , and the peripheral speed of the delivery roller 12 is V ₂
In this case, the overfeed amount (of) is defined as of(%)=V ₁ -V ₂ /V ₁ ×100. Under such an overfeed amount, a primary yield strength of 0.5 g/de or more can be secured, and at the same time, the torque can be suppressed to 50 cycles/m or less. If this torque is 50 times/m2 or less, the occurrence of snarls during knitting is also reduced, and the knitting properties are improved to a practically acceptable level. As described above, according to the present invention, it is possible to provide a false-twisted fused yarn that is substantially free from the influence of torque during knitting and has a high primary yield strength. A product with a beautiful eye surface that is both durable and bulky can be obtained. The methods for measuring the primary yield strength and torque shown in the text and examples are as follows. Primary Yield Strength This is the value obtained by drawing a load-elongation curve under the following conditions, reading the load at a point that deviates from the straight line in the first straight part of the elongation curve, and dividing it by a separately measured denier. Sample length: 20cm Tensile speed: 100%/min Torque Remove approximately 120m of the sample from the pirn and apply a light load (0.001g/de) to the center. Place both ends of the sample together and secure it to the table with cellophane tape, with the load on the bottom. Once the sample has been twisted and the load has stopped, hold the top and bottom of the sample to prevent it from untwisting, and attach it to a twister to untwist it. The grip distance of the twisting machine is 50 cm, and the number of twists (T/m) between 100 cm is expressed. Example 1 Polyethylene terephthalate chips with an intrinsic viscosity of 0.64 were melted and discharged from a spinneret at a spinning speed of 3500 m/
A multifilament yarn (110 de/36 fil) with a triangular cross section obtained by winding the yarn at a speed of 10 min was subjected to false twisting using a Teijin Seiki FW-false twisting machine under the following conditions to obtain a false twisted fused yarn. . False twisting processing conditions (1) Number of false twists 2390T/M (2) Tensile ratio during false twisting (stretching ratio between supply roller 4 and intermediate roller 7 in Figure 4) 1.3 (3) Primary heater temperature 235℃ (heater length 100cm) (4) Secondary heater (ambient temperature) 240℃ (heater length 60cm) (5) Overfeed amount (on secondary heater) Various changes between 1% and 20% (6) Processing Speed: 90 m/min Next, Table 1 shows the results of measuring the primary yield strength and torque of the obtained false twisted fused yarn.

[Table] The torque of the false twisted fused yarn before the secondary relaxation heat treatment is
100 times/It was hot with rice. In addition, smooth knitting was obtained using the above-mentioned false twisted fused yarns Nos. 1 to 11 individually under the following knitting conditions. Table 2 shows the results of evaluation of each knitted fabric in terms of sink marks during knitting, eye surface, and crispness in a sensory test.

【table】

[Table] Example 2 Polyethylene terephthalate chips with an intrinsic viscosity of 0.64 were melted and discharged from a spinneret at a spinning speed of 1800.
The yarn was wound at a speed of m/min to obtain an undrawn yarn of 260 de/36 fil. This undrawn yarn was stretched 3.5 times and heat treated at 180°C to obtain a drawn yarn. This thread is manufactured by Teijin Seiki Co., Ltd.
A false-twisted fused yarn was produced using a false-twisting machine under the following conditions. False twisting processing conditions (1) Number of false twists 2500T/M (2) Primary overfeed amount (overfeed amount between supply roller 4 and intermediate roller 7 in Figure 4) 3% (3) Primary heater Temperature 250℃ (Heater length 100cm) (4) Secondary heater (ambient temperature) 253℃ (Heater length 60cm) (Heater length 60cm) (5) Overfeed amount (on secondary heater) 1%
(6) Processing speed: 90 m/min Next, Table 3 shows the results of measuring the primary yield strength and torque of the obtained false-twisted fused yarn.

[Table] The torque of the false twisted fused yarn before the secondary relaxation heat treatment is
120 times/It was hot with rice. Moreover, smooth knitting was obtained under the above-mentioned knitting conditions using the above-mentioned false-twisted fused yarns No. 12 to 18 individually. Table 4 shows the results of evaluation of each knitted fabric in terms of sink marks during knitting, eye surface, and crispness in a sensory test.

【table】

【table】 [Brief explanation of the drawing]

FIG. 1 shows the strength and elongation curves of a false-twisted fused yarn, where a is the one according to the present invention and b is the one based on the normal wooly processing overfeed rate. FIG. 2 shows an example of the manufacturing process of the false twisted fused yarn of the present invention. 1: Original yarn, 2: Cheese, 3: Guide, 4: Supply roller, 5: False twister, 6: First heater, 7: Intermediate roller, 8: Untwisted continuous fused yarn, 9: Friction roller , 10: Bobbin, 11: Hollow pipe heater, 12: Delivery roller.

Claims (1)

[Claims] 1. A filament yarn made of a single material, with no substantial difference in yarn length between the filaments, and continuously fused while the yarn as a whole is twisted alternately in the S direction and the Z direction. to give the appearance of a focused state, and 50
A highly twisted textured yarn characterized by having a torque of less than 100 g/m and a primary yield strength of 0.5 g/de or more. 2. After false twisting and crimp processing is applied to polyester filament yarn made of a single material so as to continuously produce a fused state in the yarn axis direction, when further performing secondary relaxation heat treatment, the relaxation heat treatment is performed. Sometimes 2%~
A method for producing a highly twisted textured yarn characterized by performing heat treatment under 7% overfeed. 3. The method for producing a highly twisted textured yarn according to claim 2, wherein the overfeed amount is 3 to 5%. 4. The method for producing a highly twisted textured yarn according to claim 2, wherein the heat treatment is carried out at 230 to 255°C.