JPS6153447B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing false twisted yarn using nylon 6 multifilament yarn. Specifically, the present invention relates to a method for producing highly crimped yarn using undrawn yarn spun at high speed and at high speed. Conventionally, the method of making highly crimped yarn using nylon 6 multifilament yarn is to twist the yarn to double twist using the false twisting method or the Italian method, and heat set it.
A method is known in which a double-twisted coil type crimped yarn is obtained by untwisting the yarn thereafter. However, with these conventional methods, it was difficult to obtain industrially stable yarns, and there were also problems in productivity. recent years,
In order to reduce costs, false-twisting factories have begun to increase the processing speed of false-twisting. Therefore, rather than increasing the spindle speed by holding the spinner in its roller nip, false twisting uses a so-called magnetic spindle, which has been improved to hold the spinner with a magnet and increase the spindle speed. There are more and more machines. In this way, over the past few years, efforts have been made to improve the productivity of existing false-twisting machines by modifying them, and conventionally, false-twisting speeds of up to 120 m/min were mainstream, but recently In fact, speeds of 120m/min or more are becoming common. However, this is only in the field of normal false twisting, and in the field of high crimping processing technology targeted by the present invention, the desired high crimping yarn can only be achieved at processing speeds of up to 100 m/min. The reality was that it was not possible. As a method for obtaining highly crimped yarn using nylon 6 multifilament yarn,
Although this method is proposed in the issue,
There is a possibility of adoption if the processing speed is up to 100m/min, but if the processing speed is higher than 100m/min, DR (stretching ratio)
Since the level deviates from the appropriate range, yarn breakage during false twisting increases and the quality of processed yarn deteriorates. Furthermore, when high-crimp false twisting is performed at a speed of 100 m/min or more using nylon 6 multifilament yarn spun at a high speed of 3500 to 4500 m/min as in the present invention, the moisture content of the supplied raw yarn is Since it has a very large effect on the dyeability of the yarn, it is extremely important to maintain the difference in moisture content between the layers of the yarn package within a certain range during false twisting. In other words, when obtaining a highly crimped processed yarn at a speed of 100 m/min or more, if the above-mentioned DR (draw ratio) setting and moisture content control of the supplied raw yarn are not appropriate, the processed yarn will not have the desired stable quality. I can't get it. Crinkling spots and dyeing spots occur in the yarn length direction or between the processed yarn cheeses, and the knitted fabric ends up having defects in the warp and weft directions. The present invention was made in view of the current situation, and the purpose is to obtain a processed yarn that can be produced industrially in a stable manner, has high crimping properties with stretch properties, and is necessary for making woven and knitted fabrics with beautiful eyes. That is. That is, the present invention uses a nylon 6 multifilament yarn spun at a high speed of 3,500 to 4,500 m/min to undergo false twisting at a speed of 100 m/min or more, and the nylon is prepared by satisfying the following conditions at the same time. This is a false twisting method characterized by imparting false twist to filament yarn. 37000/√D≦T≦50000/√D ……(1) W ₁ −W ₂ ＜2.0 ……(2) 1.25＜DR＜1.43 ……(3) 185≦H≦200 ……(4) However, D: Fineness (denier) of the supplied yarn T: Number of false twists (T/M) W ₁ : Moisture content in the outer layer of the supplied yarn package (%) W ₂ : Moisture content in the inner layer of the supplied yarn package ( %) DR: Stretching ratio (times) between feed roller and delivery roller H: False twisting heater temperature (° C.) The present invention will be described in detail below. The reason why the raw yarn supplied in the present invention is a nylon 6 multifilament yarn obtained by high-speed spinning at 3500 to 4500 m/min is as follows. In other words, if the spinning speed of the supplied raw yarn is less than 3500 m/min, even if the raw yarn obtained therefrom is subjected to false twisting, a stable textured yarn cannot be obtained, yarn breakage occurs frequently, and the dyeing of the processed yarn becomes difficult. Spots occur on the genitals. On the other hand, when raw yarn obtained at a spinning speed of over 4500 m/min is supplied, it is difficult to obtain a highly crimped yarn, and the resulting processed yarn has weak crimpability, making it difficult to obtain the desired processed yarn. do not have. Therefore, it is most appropriate to use a spinning speed of 3,500 m/min to 4,500 m/min as the raw yarn to be supplied. Spinning speed 3500m/min~
Undrawn yarn spun at 4500 m/min has birefringence △n
is preferably in the range of approximately 55×10 ⁻³ to 45×10 ⁻³ . In order to obtain a stable highly crimped false twisted yarn using this raw yarn, the number of false twists, moisture content, drawing ratio, and heater temperature, which were not considered problems with conventional false twisting speeds of less than 100 m/min, must be adjusted. It turned out that it was necessary to set the range. Therefore, in the present invention, in order to obtain highly crimped yarn at a false twisting speed of 100 m/min or more, the number of false twists must be 37000/√DT/M or more (where D is the fineness denier of the supplied raw yarn). If there is 37000/√DT
/M If the number of false twists is less than that, it will not be possible to obtain a woven or knitted fabric with stretch properties, and the desired highly crimped yarn will not be obtained. Also, the number of false twists T
If it exceeds 50,000/√DT/M, the strength of the processed yarn obtained from this decreases significantly, and the processed yarn becomes fluffy, making it impossible to obtain a processed yarn that can withstand use. Therefore, the number of false twists T is 37000/√D≦T≦50000/√
It is necessary that it be within the range of D. In addition, if the moisture content of the supplied raw yarn package differs by 2% or more between the outer layer and the inner layer, there will be a difference in the dyeability of the processed yarn, and when these are mixed to make a woven or knitted fabric, This results in a woven or knitted fabric with warp lines and weft steps. The outer layer portion or inner layer portion of the package corresponds to the outer layer and the inner layer when the winding layer is divided into three parts: an outer layer, a middle layer, and an inner layer. In addition, the stretching ratio between the feed roller and delivery roller during false twisting is
If it is less than 1.25, the twisting tension of the processing tension will be low, ballooning will increase, and stable processing will not be possible and yarn breakage will occur frequently. Also,
If the stretching ratio is 1.43 or more, the processed yarn will also have a lot of fuzz, making it impossible to obtain a good processed yarn. Therefore, the stretching ratio DR needs to be in the range of 1.25<DR<1.43. Furthermore, it is most preferable that the false-twisting heater temperature H (°C) is 185≦H≦200; if it is less than 185°C, the crimp fastness of the processed yarn will be weak, and strong stretchability will not be obtained.
It is difficult to obtain the fineness and stretchability of woven or knitted fabrics. On the other hand, the temperature of the false twisting heater is
If the temperature exceeds 200°C, processed yarn fuzz tends to occur and the strength of the processed yarn decreases significantly, making it impossible to obtain a good processed yarn. For this reason, it is also preferable that the false-twisting heater temperature H (° C.) is in the range of 185≦H≦200. As described above, in the false twisting method at a false twisting speed of 100 m/min or more, stable highly crimped yarn can only be obtained by satisfying all of the conditions (1) to (4) above. It is. A woven or knitted fabric using the obtained false-twisted yarn can have a fine and uniform texture on the surface of the fabric, and can also have stretch properties. The present invention will be explained below with reference to Examples, but the present invention is not limited thereto. Example 1 Spinning using nylon 6 chips with a relative viscosity of 2.6
The spinning speed was varied from 260°C to 270°C as shown in Table 1, from Samples A to H, and the false-twisting conditions were changed using a Mitsubishi Heavy Industries ST-6 model false-twisting machine. The results were shown. Conditions suitable for the method of the present invention are D and E, and A, B, C, F, G, and H are comparative examples for clarifying the effects of the present invention. The brand of yarn spun at this time was SD82 denier 24 filament. Further, in Table 1, ◯ indicates good, △ indicates slightly poor, and × indicates poor.

[Table] Example 2 Temperature spinning using nylon 6 chips with a relative viscosity of 2.5
The 82-denier nylon 6 multifilament yarn obtained by discharging it from a 24-hole spinneret at 265°C and a spinning speed of 4300 m/min was false-twisted using a Mitsubishi Heavy Industries ST-6 type false-twisting machine under the following conditions. I did the processing. The false twisting processing conditions were spindle rotation speed 55×10 ⁴ rpm heater temperature 190℃, false twist number 4450T/M, DR 1270, yarn speed 123.6m/min, and the moisture content of the outer layer of the supplied yarn package at that time was The moisture content in the inner layer was 3.7%. The results are shown in Table 2, and the processed yarn obtained had high crimp, low torque, and a processed yarn fineness of 72 denier. The above-mentioned processed yarn was knitted with an interlock structure using a double jersey knitting machine (Fukuhara Seiki JIL-7 type pot diameter 30 inches, gauge 28G), and then subjected to normal scouring,
The jersey obtained by dyeing and finishing was a fabric with unprecedented stretch in both warp and weft. As shown in Table 2 as Comparative Example 1, the results are shown when the same yarn is used but the false twisting conditions are changed. It was not possible to obtain a highly crimped yarn, and the fabrics woven and knitted from this yarn were stiff, paper-like fabrics with no stretch. Example 3 Using nylon 6 chips with a relative viscosity of 2.6, 80 denier nylon 6 multifilament yarn was spun from a 12-hole spinneret at a spinning temperature of 260°C and a spinning speed of 4100 m/min into a temporary ST-6P model manufactured by Mitsubishi Heavy Industries. False twisting was performed using a twisting machine under the following conditions. The false twisting processing conditions are a spindle rotation speed of 50×10 ⁴ r.
pm, heater temperature 188℃, false twist number 4320T/M, draw ratio 1265, yarn speed 115.7m/min, moisture content in the outer layer of the supplied yarn package was 4.3%, and moisture content in the inner layer was 3.0%. It was hot. The results are shown in Table 2. When the obtained processed yarn was knitted using a tube knitting machine (Koike Iron Works 31/2" x 240N), a knitted fabric with a beautiful surface and low torsion torque was obtained. .Furthermore, this processed yarn is used for the warp and weft,
By weaving a fabric with a warp density of 110 threads/inch and a weft density of 90 threads/inch, and dyeing it through the usual scouring, relaxation, and dyeing finishing processes, a two-way stretchy fine-grained fabric was obtained. was completed. As Comparative Example 2, Table 2 also shows the results of false twisting a yarn in which the difference between the moisture content in the outer layer and the inner layer of the package was 2% or more.

【table】

Claims (1)

[Claims] 1. Using nylon 6 multifilament yarn spun at a high speed of 3500 to 4500 m/min, the false twisting speed is
A false-twisting method characterized in that when false-twisting is performed at a speed of 100 m/min or more, false twisting is imparted to the nylon filament yarn while satisfying the following conditions at the same time. 37000/√D≦T≦50000/√D ……(1) W ₁ −W ₂ ＜2.0 ……(2) 1.25＜DR＜1.43 ……(3) 185≦H≦200 ……(4) However, D: Fineness (denier) of the supplied yarn T: Number of false twists (T/M) W ₁ : Moisture content in the outer layer of the supplied yarn package (%) W ₂ : Moisture content in the inner layer of the supplied yarn package ( %) DR: Stretching ratio between feed roller and delivery roller (times) H: False twisting heater temperature (°C)