JPS6399338A - False twisting processing method - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for high-speed temporary twisting of synthetic fiber filament yarns.

[Prior art] Conventionally, swimsuits, sportswear, pantyhose,
The processing speed in the temporary twisting process to produce fine denier synthetic fibers for clothing with shrinkage, which make up stretchable knitted fabrics for clothing such as tights, has increased dramatically due to the number of friction plate twisting twisters. However, the processing speed is still only about 1200 m/min at most.

[Problems to be Solved by the Invention] In order to realize even higher processing speeds, there are various problems that must be solved.

The first problem is that as the machining speed increases, unsteady ballooning occurs during temporary twisting, resulting in poor workability. In order to suppress this, it is common to increase the tension, but if a high tension is applied during temporary twisting, the resulting twisted yarn will have poor shrinkage and elongation. This causes new problems such as a decrease in the shrinkage rate, a high shrinkage rate, and an increase in fuzz and yarn breakage.

The second problem is that in high-speed temporary twisting, the threading properties at the start are very poor.

In order to solve the above-mentioned problems, attempts have been made to reduce the processing speed only when threading is done, and to speed up the entire process when threading is finished. However, this method is effective when the temporary twisting speed is around 500 to 1000 m/min, but when the temporary twisting speed exceeds 1000 m/min and approaches 2000 m/min, this method is no longer sufficient. .

In view of the above-mentioned points, an object of the present invention is to provide a high-speed temporary twisting process that realizes threading with an extremely high success rate, which has not been possible with conventional techniques. It is.

[Means for Solving the Problems] The temporary twisting method of the present invention that achieves the above-mentioned object has the following configuration.

That is, in a temporary twisting method in which a synthetic fiber filament yarn is drawn and temporarily twisted at the same time using a temporary twisting device having a supply roller, a heater, a cooling device, a twister, and a take-off roller in this order, threading is performed under low speed conditions. A temporary twisting processing method characterized in that the stretching ratio under the low-speed conditions is made smaller than the stretching ratio under the high-speed conditions, after which the overall speed is increased and constant operation is performed under high-speed conditions. be.

[Effect] Hereinafter, the present invention will be roughly explained in detail.

The main point of the temporary twisting method of the present invention is to perform the threading work at a speed lower than the steady operating speed of the temporary twisting process and at a low draw ratio, while promptly speeding up the supply roller, twister, and take-off roller. This is a temporary twisting method in which the stretching ratio is increased and steady operation is performed under high speed conditions.

The temporary twisting device according to the present invention has a supply roller, a heater, a cooling device, a twister, and a take-off roller, and is a device that temporarily twists synthetic fiber filament yarn at the same time as drawing it. In addition to the above, a device having a second heater and a second take-off roller can also be used.

In the temporary twisting method of the present invention, the take-up roller speed is 1000
m/min or more, and for this reason, the temporary twisting processing device must be suitable for high-speed processing, and a friction plate twisting type such as a friction twister or a heat nip type twister is used. It is appropriate to use a temporary twisting device equipped with a twister.

Synthetic fiber filament yarns include polyester,
Thermoplastic synthetic fiber filament threads such as polyamide can be used. Denier J: and number of filaments is 10
-300 denier, preferably within the range of 3-150 filaments.

In the method of the present invention, the take-up roller speed under high-speed conditions is 1000 m/min or more, preferably 140 m/min or more.
0 m/min or more, and most preferably 2000 m/min or more
m/min or more.

On the other hand, the speed of the take-up roller under the low-speed condition is preferably 50% or less of the speed of the take-up roller under the high-speed condition; It is appropriate to set the speed to about 200 m/min. If the take-up roller speed is extremely low when threading, there is a problem in that it takes time to thread the thread, and conversely, if the take-up roller speed is increased too much, the success rate of thread threading becomes low and work efficiency decreases. .

Further, the method of the present invention includes stopping the temporary twisting device,
It can also be applied to a temporary twisting method in which each part of the device is threaded one after another, then the operation is started all at once, and the speed of the entire device is gradually increased.

In the method of the present invention, it is necessary to make the draw ratio under low speed conditions smaller than the draw ratio under high speed conditions.

By setting the draw ratio under low-speed conditions and the draw ratio under high-speed conditions separately in this way, a draw ratio suitable for each condition can be set. That is, under low-speed conditions, a draw ratio that allows threading to be carried out most efficiently is set, and under high-speed conditions, a draw ratio that allows steady production to be carried out most stably is set. Regarding this point, in conventional temporary twisting processing methods, it was not necessary to consider both separately, but in high-speed board twisting, which is the subject of the present invention, it is extremely important to set the draw ratios for both separately. Being rational is a new finding.

The appropriate range of the draw ratio under high-speed conditions and the appropriate range of the draw ratio under low-speed conditions cannot be determined unambiguously because they vary depending on the properties (mainly elongation) of the synthetic fiber multifilament yarn that is the raw material. In the case of polyester semi-drawn yarn, the draw ratio under high speed conditions can be 1.8 to 2.0 times, and the draw ratio under low speed conditions can be in the range of 1.7 to 1.8 times.

The stretching ratio under low speed conditions is preferably 0.05 to 0.20 times lower than the stretching ratio under high speed conditions.

For polyamide semi-drawn yarn, the draw ratio under high speed conditions is 1.3 to 1.35 times, the draw ratio under low speed conditions is 1.25 to 1.28 times, and the difference between the two is 0. .0
It is preferable to set it as 2 to 0.05 times.

In the method of the present invention, the relationship between the take-up roller speed VDH (m7 minutes) and the additional tension H (Q/denier of temporary twist yarn) under high-speed conditions is preferably as follows. By adopting this method, it is possible to operate the temporary twisting machine more stably under the above-mentioned high-speed conditions. In other words, under such high-speed conditions, it is desirable to configure the tension T11 to be 1°6 or less; if the tension exceeds 1.6, it may cause problems such as fluffing and a decrease in processing strength and elongation. Problems arise such as deterioration of quality and an increase in thread breakage during temporary twisting. The tension TH is preferably 1.4 or less, most preferably 0.8 or less. Furthermore, the same tension T
When H becomes smaller than 2.5×10 −4 , processing under high-speed conditions becomes unstable, leading to problems such as increased yarn breakage and increased yarn unevenness such as uneven shrinkage.

In addition, in the tentative twist processing method of the present invention, the draw ratio under low speed conditions at the start is the draw ratio under high speed conditions during constant speed operation (=VFH/VDH, where ■□ is the supply roller speed (m7 minutes)). this is,
During the thread threading operation, the thread is threaded onto the supply roller and the take-up roller, and the thread is threaded onto the twister at the same time without the thread coming into contact with the heating device of the temporary twisting device, or without the heating device working sufficiently. The high tension conditions that occur when threading the temporary twisting device can be avoided by either threading or threading the take-off roller and twister and then the supply roller. , Threading improves sex.

On the other hand, the stretching ratio in the process of increasing the speed from low speed conditions to high speed conditions (=VD/VD, where ■ is the supply roller speed (m7 min) in the process of increasing the speed from low speed conditions to high speed conditions) is , Stretching ratio under high speed conditions during low speed operation (
=■DH/■FI). By doing this, it is possible to ``minimize yarn breakage due to high tension during the process of speeding up from low speed conditions to high speed conditions''.

Furthermore, in the method of the present invention, when transitioning from low speed conditions to high speed conditions, the take-up roller speed VD and the tension T are as follows:
It is preferable to satisfy the following relationship.

T≧2.5 By setting the thread in the above range, it is possible to minimize the occurrence of thread breakage due to unstable phenomena during the process of increasing the speed from the start to the high speed condition in steady operation.

[Example] Hereinafter, the specific structure and effects of the present invention will be explained using examples.

EXAMPLE Temporary twisting was performed using the temporary twisting device shown in FIG.

In this process, the raw yarn is unwound from the package 1 and fed to the supply roller 2, and the fed raw yarn is roughly fed to the heating device 3,
Cooling device 4 and belt nip type twister 5
After heat setting and twist fixing, the yarn is unrolled and taken up by a take-up roller 6, and finally the temporarily twisted yarn is wound up by a winding device 7.

During processing, yarn threading was carried out under the following low speed conditions, and the speed was roughly increased to the following high speed conditions of steady operation.

As a result, we were able to realize a temporary twisting process that allows for good threading and does not cause fuzz or thread breakage. Temporarily twisted yarn fineness is 6
It was 9.5 denier.

(1) Temporarily twisted raw yarn: Polyester multifilament, fineness 139 denier, elongation 180%, birefringence △n = 0.037. 36 filament, semi-dull, round cross section (2) Low speed conditions: Take-up roller speed 600 m/ minutes, twister belt surface speed 800 m/min, twister belt crossing angle 100 degrees, supply roller speed 325 m/min, tension tension 32 Cl, drying plate temperature 220°C, stretching ratio: 1.85 times, (3) High speed conditions: Take-back Roller speed 2000 m/min, twister belt surface speed 2750 m/min, twister belt crossing angle 100 degrees, supply roller speed 1000 m/min, drying plate temperature 220°C, tension tension 10 g, stretching ratio: 2x, Comparative Example 1 Using the temporary twisting device shown in the figure, an attempt was made to start temporary twisting using the same temporary twisting raw yarn as in the above example and under the same high speed conditions.

At this time, under the low speed conditions described below, the tension during threading was extremely high and threading was impossible.゛Low speed conditions: take-up roller speed 600 m/min, twister belt device 825 m/min, twister belt crossing angle 100 degrees, supply roller speed 300 m/min, drying plate temperature 220°C, measurement impossible due to breakage of the stretched crab thread.

Stretching ratio = 2 times,

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an example of a temporary twisting apparatus that can preferably carry out the temporary twisting method of the present invention. 1: Package 2: Supply roller 3: Heater 4: Cooling device 5: Twister 6: Take-up roller 7: Winding device

Claims (1)

[Scope of Claims] (1) A temporary twisting method in which a synthetic fiber filament yarn is simultaneously drawn and temporarily twisted using a temporary twisting device having a supply roller, a heater, a cooling device, a twister, and a take-off roller in this order, A feature is that when threading work is carried out under low speed conditions, and then the overall speed is increased to perform steady operation under high speed conditions, the draw ratio under the low speed conditions is made smaller than the draw ratio under the high speed conditions. Temporary twist processing method. (2) Take-up roller speed V_D_H (m
/min) and additional tension T_H (g/denier of temporary twist yarn)
The temporary twisting method according to claim (1), wherein the following relationship is established: V_D_H≧1000 1.6≧T_H≧2.5×10^-^4·V_D_H. (3) The temporary twisting method according to claim (1), characterized in that the stretching ratio in the process of increasing the speed from low speed conditions to high speed conditions is smaller than the stretching ratio under the high speed conditions. (4) The relationship between the take-up roller speed V_D (m/min) and the applied tension T (g/denier) in the process of increasing the speed from low speed conditions to high speed conditions is T≧2.5×10^-^4・V_D+0. 1. A temporary twisting method as set forth in claim (1), (2), or (3).