JPH08291425A - Production of polyester fiber - Google Patents

Abstract

PURPOSE: To suppress the generation of single fiber breakage or yarn breakage even at high speed spinning at >=4000m/min and stably produce a package having excellent wound shape and applicable to high speed weaving by applying a specific oil on a polyester fiber. CONSTITUTION: An oil has a fiber to fiber static friction at 20 deg.C of 2.25-2.50 and that at 60 deg.C of 2.75-3.00. Usually, the oil is applied on a polyester fiber at the point before a pulling roller in an amount of 0.2-1.0wt.% based on the fiber weight, and high speed spinning is carried out at a winding speed of >=4000m/min to obtain the objective polyester fiber.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing polyester fiber, and more specifically, a spinning speed of 4000 m /
The present invention relates to a method for producing a polyester fiber capable of obtaining a package having a good winding shape without impairing the spinnability in high-speed spinning for more than a minute.

[0002]

2. Description of the Related Art The progress of synthetic fiber spinning technology has been remarkable, and especially in recent years, with the development of high-speed winders, the spinning speed has been increasing. These technologies focus on the improvement of discharge productivity and the application development as a peculiar material resulting from the change in the fiber microstructure peculiar to the spinning process,
Various research and development are being promoted. However, as the spinning speed increases, abrasion between the traveling yarn and various yarn guides or abrasion between fibers within the traveling yarn bundle increases, which not only impairs the quality of the obtained yarn, but rather increases the production efficiency. It includes the problem of lowering.

In order to solve these problems, JP-A-3-
Japanese Patent No. 871 proposes a method of applying an oil agent containing an ester compound having an alkyl group having 30 to 50 carbon atoms to a yarn. Indeed, according to this method, the oil film strength of the oil agent is improved and the fiber / fiber static friction is reduced,
Single yarn breakage and yarn damage are less likely to occur even under high-speed spinning conditions,
It is possible to obtain a good quality fiber with less fluff. However, there is a problem that a defective winding shape such as a bulge (usually called a bulge) on the end surface of the winding package is likely to occur.

[0004] In such a package, in high-speed weaving, in which the number of revolutions of the loom has become 700 rpm or more, which has been widely adopted in recent years, the unwinding speed exceeds 1000 m / min, so that the unwinding can be performed even if the winding shape is slight. There is a problem that it does not go smoothly, and especially when it is used for wefts, there is a problem that a yarn breakage stop and a fabric defect are likely to occur, and further improvement is strongly desired.

[0005]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned drawbacks of the prior art, and even in high-speed spinning at a spinning speed of 4000 m / min or more, single yarn breakage or yarn breakage is less likely to occur in the spinning process, and winding An object of the present invention is to provide a method for producing a polyester fiber, which is capable of stably obtaining a package having a good appearance and capable of supporting high-speed weaving.

[0006]

In order to achieve the above object, the present inventors have found that it is not sufficient to lower the fiber / fiber static friction coefficient at 20 ° C. of an oil agent, and it has been considered so far. It was found that it is extremely important to use an oil agent having a fiber / fiber static friction coefficient within a specific range at 60 ° C., which has led to the present invention.

That is, according to the present invention, when polyester fiber is produced at high speed at a winding speed of 4000 m / min or more, the polyester fiber has a fiber / fiber static friction of 2.25 to 2.50 at 20 ° C. A method for producing a polyester fiber, which comprises applying an oil agent having a fiber / fiber static friction of 2.75 to 3.00 at 60 ° C. of 0.2 to 1.0% by weight based on the fiber weight. To be done.

The polyester fiber referred to in the present invention is mainly made of a polyester whose main repeating unit is ethylene terephthalate, for example, a fiber made of polyethylene terephthalate, and is spun at a spinning speed of 4000 m / min or more, preferably 3000 to 4000 m. It is applied to the fibers which are drawn at a rate of / min and then drawn.
When the spinning speed is less than 4000 m / min, even if a conventional widely used refueling oil agent is used, there is no problem in process condition or quality, so it is out of the scope of the present invention. The effect is exhibited only when the yarn is spun at a spinning speed of not less than / min.

In the present invention, the fibers which have been subjected to high-speed spinning, usually the spun fibers, have a fiber / fiber static friction of 2.25 to 2.50 at 20 ° C. and fiber / fibers at 60 ° C. It is necessary to apply an oil agent having a static friction of 2.75 to 3.00. The term "fiber / fiber static friction" as used herein means that the amount of deposited oil agent is 0.5% by weight.
It is measured by the following method using a device shown in FIG. 1 using denier / 36 filament polyester multifilament.

That is, as shown in FIG. 1, the fiber (1)
One end of the is fixed to the U gauge (2), applied to the pulley (3), and further twisted 4 times and pulled by a load (W) of 20 g. Set the fiber / fiber crossing angle (θ) to 20 °,
The temperature of the twisted portion is maintained at 20 ° C. or 60 ° C. (in this case, the twisted portion is heated by the heater plate (4)), and the U gauge (2) is pulled at a speed of 0.1 m / min. At that time, the tension (T ₂ ) g sensed by the U gauge (2) is measured, and (T ₂
/ W) was used as the fiber / fiber static friction.

Fiber / fiber static friction at 20 ° C. is 2.
When it is less than 25, the package shape retention of the wound fiber becomes insufficient, which causes problems such as deterioration in operability and unwindability of the fiber, which is not preferable. on the other hand,
If it exceeds 2.50, the friction between the fibers in the running yarns increases, and single yarn breakage and eventually yarn breakage are induced, which impairs the quality of the obtained yarn, which is not preferable. Also, 60
If the fiber-to-fiber static friction at ℃ is less than 2.75, it is presumed that the gripping property between fibers at the time of winding will be poor, and defective winding shape such as bulging of the package end surface will occur, resulting in poor operability. And the unwinding property of the fiber in the post-processing step are not preferable.
On the other hand, when it exceeds 3.00, the friction between the fibers in the running yarn is increased, and the single yarn breakage and eventually the yarn breakage are induced, which not only impairs the quality of the obtained yarn but also lowers the production efficiency. It is not preferable because it causes.

The oil agent used in the present invention may have any composition as long as it satisfies the above-mentioned characteristics. For example, a mono- or divalent aliphatic ester compound having a molecular weight of 450 to 500 is used as a main smoothing agent component, As an oil film strength improving component, a compound containing a polyoxyalkylene glycol-based copolymer can be exemplified. Specifically, as the aliphatic ester compound, isocetyl palmitate, isotridecyl stearate, diethylene glycol dilaurate,
Glycerin dilaurate and oleyl myristate are preferably used, and the polyoxyalkylene glycol copolymer has an average molecular weight of 4,000 to 7,000.
A propylene oxide / ethylene oxide (weight ratio 60/40 to 40/60) block copolymer is preferably used. At this time, the compounding amount of the aliphatic ester is
The aliphatic ester occupies 50% by weight or more of the smoothing agent component in the oil agent, and the proportion of the entire lubricating agent component in the oil agent is 50 to 70% by weight, while the above polyoxyalkylene glycol is used. The blending amount of the copolymer is such that the proportion of the compound in the oil agent is 10 to 15% by weight.
It is preferable that This reduces the oil film strength of the polyoxyalkylene glycol copolymer at a high temperature of 60 ° C.
Static friction between fibers is high, and the winding shape of the package is good.

The above-mentioned oil agent may be applied to the polyester fiber after the spun yarn is solidified, but it is usually applied before the take-up roller. As a preferable means for applying, there is a means for forming the above-mentioned oil agent in an aqueous emulsion and applying it through a metering oiling nozzle, but it is not limited to this. The applied amount is 0.2-based on the fiber weight.
It should be 1.0% by weight, and by doing so, the yarn formability is improved and the winding shape of the package is improved.
If the applied amount is less than 0.2% by weight, it will be difficult to suppress single yarn breakage even with the use of the above oil agent, and it will not be possible to stably produce homogeneous fibers. On the other hand, 1.
If it exceeds 0% by weight, the excess oil agent is easily scattered,
Not only is it unfavorable for the working environment but also for the cost of the lubricant.

[0014]

In the past, the defective winding form of the wound package is considered to be due to the large slippage between the fibers and the inability to maintain the form, and it is possible to increase the static friction between the fibers at 20 ° C. It has been regarded as a means of improvement. However, at a spinning speed of 4000 m / min or more, 20 ° C
When the static friction between fibers / fibers is increased, single yarn breakage occurs frequently and only fluff is obtained, so the static friction between fibers / fibers cannot be sufficiently increased, and there is a limit to improving the winding shape of the package. .

On the other hand, according to the present invention, when wound at a spinning speed of 4000 m / min or more, the winding shape of the package is not only the fiber / fiber static friction of the oil agent at 20 ° C. but also 60 ° C. It was also found that it also changes depending on the fiber / fiber static friction. That is, 4000m
At a spinning speed of more than 1 minute, the package will reach about 60 ° C due to friction with the winding winder.
It has been found that keeping the static friction between fibers within a specific range is effective in improving the winding shape of the package. Then, when an oil agent having characteristics such that the fiber / fiber static friction at 20 ° C. is 2.25 to 2.5, while the fiber / fiber static friction at 60 ° C. is 2.75 to 3.00 is applied, It is possible to obtain a package with a good winding shape without impairing the high-speed yarn formability.

[0016]

EXAMPLES The present invention will be further described below with reference to examples. The winding shape and the thread-forming property are obtained by the following methods. (1) Winding shape (bulge) As for the bulge, the swelling width of the end face with respect to the original winding width of a package having a winding amount of 7 kg was measured in mm. (2) Spinnability (original yarn fluff) 160 original yarns were sampled and the number of fluffs (single yarn breaks) at a length of 120,000 m each was counted and integrated, and as the number of fluff per 10 ⁶ m I asked.

Example 1 Polyethylene terephthalate having an intrinsic viscosity [η] of 0.64 was melted and discharged to form a 36-filament yarn. After solidification of this yarn, 0.5% by weight of the oil agent shown in Table 1 was applied to the yarn weight through a metering oiling nozzle, and then it was taken out through a take-up roller having a surface speed of 3500 m / min, and subsequently taken as a take-up roller. Stretching 1.5 times between stretching rollers to 525
The yarn was wound at a spinning speed of 0 m / min to obtain a drawn yarn of 75 denier / 36 filament. The results are shown in Table 1. As is clear from this table, when an oil agent satisfying the requirements specified in the present invention is applied, the occurrence of fluff is reduced and the package shape is improved.

[0018]

[Table 1]

[Embodiment 2] In Embodiment 1, No. 5
A drawn yarn was obtained in the same manner as in Example 1 except that the above oil agent was used to give the amount shown in Table 2. Table 2 shows the results.

[0020]

[Table 2]

[0021]

As described above, according to the present invention, even in the high-speed spinning at a spinning speed of 4000 m / min or more,
It is possible to obtain a package with less fluff and a good winding shape. As a result, for example, when the weft yarn is used for high-speed weaving, it is possible to suppress the occurrence of a weft yarn breakage stop and a fabric defect due to unwinding failure.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing a method of measuring a fiber / fiber static friction force.

[Explanation of symbols]

 1 Fiber 2 U gauge 3 Pulley 4 Heater

Claims (3)

[Claims] 1. When high speed spinning of polyester fiber at a winding speed of 4000 m / min or more, the polyester fiber has a fiber / fiber static friction of 2.25 to 20 ° C.
A polyester fiber characterized by being provided with an oil agent having a fiber / fiber static friction of 2.75 to 3.00 at 2.50 at 60 ° C. of 0.2 to 1.0% by weight based on the fiber weight. Manufacturing method. 2. The method for producing a polyester fiber according to claim 1, wherein the polyester fiber is drawn at a speed of 3000 m / min or more, then drawn and high-speed spun at a winding speed of 4000 m / min or more. 3. The oil agent comprises 50 to 70% by weight of a monovalent or divalent aliphatic ester compound having a molecular weight of 450 to 500,
And 10 to 15% by weight of a propylene oxide / ethylene oxide copolymer having an average molecular weight of 4000 to 7000 and a copolymerization weight ratio of 60/40 to 40/60, and the method for producing polyester fiber according to claim 1 or 2.