JP2854245B2 - Winding method for partially oriented yarn - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a melt spinning of polyester fiber, wherein the spun yarn is 2,500 m / min.
When winding at 000 m / min, even if the traverse length at the time of winding is 150 mm or less, the present invention relates to a winding method whereby a yarn package composed of partially oriented polyester yarn (hereinafter abbreviated as POY) can be obtained favorably. .

[0002]

2. Description of the Related Art In recent years, with the progress of rationalization and efficiency of production equipment, it has been attempted to wind a multi-weight polyester yarn with a single winding machine. For example, six bobbins are mounted on one bobbin holder, and six yarn packages are simultaneously wound by one winding machine. In such a winding machine, in order to realize multi-spindle winding, in order to save the installation space of the winding machine and to improve workability, it is necessary to obtain a yarn package having the same winding amount. It has been practiced to shorten the traverse length of the take-up machine and to increase the winding diameter of the yarn package as a price.

[0003] The "traverse length" used in the present invention.
The word "winding" means that the running yarn is traversed (traversed) in the axial direction of the bobbin in order to wind the yarn on the bobbin, and the yarn is moved from one bobbin end direction to the other bobbin end direction. Refers to the length of one way (ie, the length of one traverse) for moving. Therefore, the traverse device of the winding machine does not indicate the double stroke length from the position at which the traveling yarn starts traversing to returning to the original position, but the half length of the double stroke length. And

In the process of forming a yarn package having a short traverse length and a large winding diameter, the winding speed is reduced to 2
In the case of less than 500 m / min or more than 4000 m / min, there is almost no difference in quality such as dyeing difference between the inner layer portion and the outer layer portion of the yarn package. However, the spun polyester fiber has a winding speed of 2500 m / min.
When winding at 4000 m / min and trying to obtain POY, the situation changes completely, and between the inner layer and the outer layer of the yarn package,
A new problem that a quality difference such as the dyeing difference appears at once is encountered.

Hitherto, various proposals have been made to maintain good quality of a wound yarn at the time of high-speed spinning of a polyester fiber.

For example, Japanese Patent Publication No. 57-11824 and Japanese Patent Publication No. Hei 5-9351 have disclosed a winding tension and a winding force in order to minimize the influence of automatically switching between a full bobbin and an empty bobbin. A method has been proposed in which the yarn switching performance is improved by controlling the peripheral speed of the bobbin to an optimum range, and the yarn quality of the innermost layer yarn of the package is reduced. Certainly, if this method is performed, the yarn quality of the innermost yarn is improved, but the quality difference from the innermost layer to the outermost layer of the yarn package cannot be totally eliminated.

[0007] As described above, any of the prior art attempts can reduce the traverse length of the polyester yarn package having a large winding diameter to a winding speed of 2500 m / m.
It was not effective against the new problem that appeared when trying to perform in the area of 〜 to 4000 m / min, and it was not possible to obtain a POY package having uniform inner and outer layers.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to solve the following problems in view of the above problems.

That is, a new problem that has arisen when forming a polyester yarn package having a short traverse length and a large winding diameter in the region of a winding speed of 2500 m / min to 4000 m / min, that is, the quality of the inner and outer layers of the POY package. Solving the difference.

[0010]

According to the present invention, there is provided the following spinning and winding method.

That is, when the spun polyester yarn is finally wound up at 2500 to 4000 m / min by a winder having a yarn traverse width of 150 mm or less, 10 to 40 with respect to the total winding amount. The winding speed is set to 0.1 to 2.0 with respect to the winding start speed until the winding amount of
A method for winding a partially oriented yarn in which the winding speed is gradually increased to reach a maximum (final) winding speed, and then the winding speed is maintained at the maximum winding speed until winding is completed, or gradually reduced from the maximum winding speed. Is provided.

Next, the spinning method of the present invention will be described in detail below, with the inventor's idea relating to the operation of the present invention.

In general, polyester fibers elongate when tension is applied to generate strain, and this strain can be divided into plastic strain and elastic strain. Then, when the applied tension is removed, only the amount of elongation corresponding to the elastic strain of the stretched fiber recovers, and the amount of elongation corresponding to the other plastic strain does not recover. Play a role in changing.

By the way, unstretched polyester fibers obtained by melt-spinning at a spinning speed of less than 2500 m / min are made into a yarn package with a certain pretension (winding tension). However, such unstretched polyester fibers are usually stretched (elongated) several times, depending on the subsequent winding conditions, so that elongation (plastic deformation) caused by micro-tension during winding is performed. At a degree, it is considered that it hardly affects the yarn quality.

In a package made of a highly oriented polyester fiber obtained at a spinning speed of more than 4000 m / min, most of the applied winding tension remains as elastic strain on the yarn. May be converted to plastic strain over time due to creep of the yarn or the like. Here, considering the case where most of the winding tension remains as elastic strain, the yarn released from the yarn package, regardless of which part of the outer layer is wound from the inner layer,
Since most of the elastic strain is recovered and released during unwinding, the effect of the winding tension on the yarn quality is extremely small. On the other hand, considering that most of the winding tension is converted into plastic strain over time, the polyester fiber obtained at the time of melt-spinning already has a highly oriented internal structure, The internal structure hardly changes in the degree of plastic elongation. For this reason, it is considered that the winding tension hardly affects the yarn quality.

On the other hand, the spinning speed is 2500 to 400.
It is widely known that the polyester fiber obtained at 0 m / min becomes a partially oriented yarn (POY).
Has an intermediate property between the unoriented yarn and the highly oriented yarn. For this reason, the elastic strain energy of the yarn converted from the winding tension changes over time with the plastic strain of the fiber (elongation deformation of the fiber).
When consumed as energy, the internal structure (degree of orientation) of the POY changes according to the degree of progress of the plastic strain.
On the other hand, the stress (strain) state of the yarns located in the inner layer (particularly, the innermost layer), the middle layer, and the outer layer of the POY package wound by the winder differs for the following reasons.

That is, in the inner layer (especially, the innermost layer), there is a bobbin (which plays the role of a rigid body) which is not deformed below, so that the winding tension is all the elastic strain in the tensile direction (tensile elastic strain). ) And converted into yarn. On the other hand, the yarn located in the middle layer receives compressive strain from the upper winding yarn, so that a part of the elastic strain in the tensile direction is offset by the elastic strain in the compressive direction. However, it is considered that the above-mentioned offset does not occur in the yarn located in the outer layer because the winding yarn does not exist above or is slightly present.

For the reasons described above, a difference in elastic strain (difference in elastic stress) is generated from the inner layer to the outer layer of the POY package, and as a result, the degree of creep progress of the yarn located in each layer (plasticity over time) The degree of deformation). In other words, the yarn at the position with the high elastic strain (the innermost layer and the outer layer) is located at the position with the low elastic strain (middle layer).
Causes greater creep than the yarn in It is considered that this result appears as a difference in quality between the inner layer, the middle layer and the outer layer of the POY package, that is, a difference in dyeing between the innermost layer, light dyeing in the inner layer and the middle layer, and light dyeing in the outer layer. And such a phenomenon produces POY (under normal conditions, the spinning speed is 2500 to 4000).
melt spinning at m / min), the traverse length is 1
It will be understood from the above description that the length is reduced to 50 mm or less, and the cost is increased when the winding diameter of the package is increased.

Further, since the winding tension generally has a certain correlation with the winding speed (the winding tension increases as the winding speed increases), the winding tension is controlled by controlling the winding speed. Can be controlled to an arbitrary pattern. For this reason, by controlling the winding tension indirectly through the management of the winding speed, it is possible to eliminate the difference in the distribution of the distortion of the yarns located in each layer of the POY package, and consequently the quality. The difference can be eliminated.

FIG. 1 is a graph showing a preferred winding speed pattern for eliminating the difference in quality of the POY package by managing the winding speed in a constant pattern. The ratio of the amount of winding yarn from the start of winding to the total amount of winding yarn on the shaft is represented by weight%. In the graph, 1 and 2 are winding patterns respectively illustrating two embodiments of the present invention. M indicates a point at which the winding speed gradually increased from the start of winding reaches the maximum winding speed.

Here, the winding pattern 1 is such that the winding speed gradually increases from the start of winding and reaches the maximum winding speed reaching point (M). FIG. 7 shows a pattern that is maintained until it becomes a certain point. further,
In the winding pattern 2, after the winding speed gradually increases and reaches the maximum winding speed reaching point (M), the winding speed remains PO
This shows a pattern in which the Y package is gradually decelerated until it becomes full.

In the present invention, in order to eliminate the quality difference between the layers of the POY package, the winding speed is increased until the winding amount becomes 10 to 40% by weight with respect to the total winding amount of the POY package. To the maximum (final) winding speed. By doing so, it is possible to reduce the distortion of the yarn located from the inner layer to the outer layer of the POY package.

The rate of the gradual increase is preferably such that the winding speed is 0.1 to 2.0% with respect to the winding start speed.
It is particularly preferred that the content be 0.1 to 1.0%. Here, when the winding speed is gradually increased to less than 0.1%, there is not much effect of equalizing the strain generated in each layer of the POY package. In addition, when the increase gradually exceeds 2.0%, a change in the internal structure of the fiber due to a difference in the spinning speed (winding speed) becomes apparent, which in turn causes a difference in the quality of the POY package. Absent. When this condition is 0.1 to
1.0% is particularly preferable because not only the quality of the POY package is improved, but also the winding appearance of the package is improved.

As described above, the gradually increasing rate of the winding speed is set to 0.
Even if it is extremely small, such as 1 to 2.0%, the fact that the difference in quality of the POY package is eliminated can be taken into account as to how meaningful the method of spinning the POY package of the present invention is. Think that you can understand.

Further, as another embodiment (corresponding to the winding pattern 2 in FIG. 1), 10 to 4 times with respect to the total winding amount.
There is a spinning winding method in which the winding speed is gradually increased with respect to the winding start speed until the winding amount becomes 0% by weight, and then the winding speed is gradually reduced. According to this method, the strain of the yarns located in the inner layer portion and the outer layer portion can be reduced, and as a result, the strain distribution can be made uniform. Therefore, the quality difference in each layer of the POY package is also eliminated. The advantage of the "gradual reduction of the winding speed" in this way is that the elastic strain distribution from the middle layer to the outer layer of the POY package can be reduced.
The tightening stress on the middle layer of the package is reduced, and the compressive elastic strain of the yarn located in the middle layer is also reduced. Therefore, the reduction of the compressive elastic strain also reduces the offset amount of the winding tension with the converted tensile elastic strain, and as a result, the strain distribution of each layer of the POY package is made uniform, and the quality is also made uniform.

The rate at which the winding speed is "gradually reduced" is
It is preferably set to 0.0 to 1.0%. That is,
Spinning speed (winding speed) when gradually decreasing beyond 1.0%
The change in the internal structure of the fiber due to the difference becomes apparent, which in turn causes a quality difference due to a difference in the winding speed of the POY package, which is not preferable. In addition, increasing the speed is not preferable because the distortion in the outer layer portion of the POY package is amplified as described above.

In the above two embodiments of the present invention, the "gradual increase" and "gradual decrease" of the winding speed do not necessarily have to be performed in a curved or straight line, but in several steps. Needless to say, the same effect can be obtained. Although the present invention has been described with respect to a POY package having a short traverse length and a large winding diameter, there is no problem if the present invention is applied to a POY package having a small winding diameter. However, in such a case, there is no reason to dare apply the method of the present invention to complicate the winding method.

[0028]

EXAMPLE In accordance with a conventional method, a molten polyethylene terephthalate having an intrinsic viscosity [η] = 0.63 was discharged from a spinneret at a spinning temperature of 290 ° C., and a standard winding speed of 3400 was used.
At a speed of m / min, it was wound by a turret type spindle drive winder having a traverse length of 120 mm. The POY package obtained at this time has a number of filaments of 48 and a denier of 240 denier.
It was a full package of g volumes. In addition, the winding conditions, the difference in quality between the inner and outer layers of the package, and the winding shape of the package were as shown in Table 1. The “gradual increase” and “gradual decrease” of the winding speed were performed in a straight line.

In Examples 1 to 3 shown in Table 1, the gradually increasing rate of the winding speed from the start of winding was set to 0.1 to 1.0%, which is a particularly preferred range of the present invention, relative to the winding start speed. This is an example of the case. In this case, the quality difference between the inner and outer layers of the package and the winding appearance of the package were particularly good. The first embodiment shows an example of the above-described winding pattern 1, and the second and third embodiments show examples of the winding pattern 2.

Next, in the fourth embodiment (winding pattern 2) and the fifth embodiment (winding pattern 1), the gradual increase rate of the winding speed from the start of winding is preferably set according to the present invention with respect to the winding start speed. The case where the range is 0.1 to 2.0% or less is exemplified. In this case, in Example 5, although the quality difference between the inner and outer layers of the package was slightly inferior to the particularly preferable range, it was clearly superior to the case where the winding method of the present invention was not applied.

On the other hand, in Comparative Example 1, the winding speed was always kept constant, and the difference in quality between the inner and outer layers of the package was particularly lower than that obtained by the winding method of the present invention. Obviously inferior.

As described in detail above, the present invention is directed to a phenomenon peculiar to the POY package, and the winding speed for manufacturing the POY package is an essential condition of the present invention. It is. Therefore, in the embodiment of the present invention, the winding speed of 3400 m / min is used as the tentative reference winding speed. This is a condition in which the present inventor has arbitrarily selected typical winding conditions for obtaining POY. According to the experiment of the inventor, the winding speed is 2500 to 4
It should be added that the effect is naturally exerted even in the range of 000 m / min.

[0033]

[Table 1]

[0034]

According to the present invention described above, in a method for winding a polyester fiber, a short traverse length,
When a POY package having a large winding diameter is wound, a POY package having no quality difference can be obtained regardless of the winding layer position. Further, according to the present method, there is a remarkable effect that the winding shape such as the height of the ear formed on both end surfaces of the outermost winding yarn of the wound POY package is improved.

[Brief description of the drawings]

FIG. 1 is a graph illustrating a winding speed pattern suitable for forming a POY package according to the present invention.

[Explanation of symbols]

 1,2 Winding pattern M Maximum (final) winding speed reached

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁶ , DB name) D01F 6/62 301 D01D 7/00

Claims (4)

(57) [Claims] 1. When the spun polyester yarn is finally wound at 2500 to 4000 m / min, the winding speed is reduced to 10 to 40% by weight with respect to the total winding amount. Is gradually increased by 0.1 to 2.0% of the winding start speed to reach the maximum (final) winding speed, and then the winding speed is maintained at the maximum winding speed until winding is completed, or the maximum winding speed is increased. A method for winding a partially oriented yarn that is gradually reduced from a winding speed. 2. The rate at which the winding speed is gradually increased to the maximum winding speed with respect to the winding start speed is 0.1% with respect to the winding start speed.
3. The method for winding a partially oriented yarn according to claim 1, wherein the amount is set to 1.0%. 3. After the winding speed reaches the maximum speed, the rate at which the winding speed is gradually reduced is 0 to 1.0% with respect to the maximum speed.
The method for winding a partially oriented yarn according to claim 1. 4. The method for winding a partially oriented yarn according to claim 1, wherein a winding machine having a yarn traverse length of 150 mm or less is used.