JPH0464987B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a method for manufacturing a polyester yarn package. More specifically, the present invention relates to a method for producing a yarn package of polyester fibers that has good stability in the winding shape and can be used directly to produce knitted fabrics of good quality. [Prior art and problems to be solved by the invention] In recent years, there has been a strong demand for improved productivity in the production of polyester fiber yarns, and high speeds exceeding 5,500 m/min, for example, have been required in the spinning process, especially in the spinning process. Attempts have been made to manufacture the fibers by the so-called high-speed spinning take-off method, which uses take-off speeds of . The polyester yarn obtained by this type of high-speed spinning and take-off method has a fine structure that is manufactured by two processes: a conventional spinning process and a drawing process (for example,
It is significantly different from spun/drawn yarn (as typified by Japanese Patent No. 57-16913), and therefore, spun/drawn yarn is said to have outstanding and useful features in terms of practically required performance. Unexamined Japanese Patent Publication 1987-
It is known from Publication No. 121613 and the like. The most outstanding features are high dyeability and low heat shrinkage in practical use. Easy dyeability is excellent to the extent that the practical dyeing temperature obtained by high-temperature, high-pressure dyeing of general-purpose low-speed spun/drawn yarn can be achieved at 110°C to normal pressure, especially when a take-up speed of 6000 m/min or higher is used. It was reported in Japanese Patent Application Laid-Open No. 1983-1983 that the effect of yarn obtained by high-speed spinning is remarkable.
It is disclosed in Publication No. 121613. In addition, low heat shrinkage means that, for example, in textiles, dimensional changes in textiles are extremely minimized during the processing steps that the gray fabric must go through after weaving, typically during refining and dyeing processes. As a result, it is possible to omit the presetting step that is performed prior to these wet processing steps. However, contrary to the above-mentioned advantages, when polyester yarn is wound into a cheese-like package using the high-speed spinning take-off method, when it is made into a fabric, minute gloss spots called sink marks occur on the fabric surface during the processing process. There are some easy drawbacks. The threads of high-speed spinning take-off are spun/
Compared to drawn yarn, the birefringence of the fibers that make up the yarn is lower due to its microstructural features, making it more susceptible to stress unevenness. Furthermore, the polyester fiber has low heat shrinkage, and since it is dyed at 110° C. and normal pressure, the heat shrinkage of the fabric is small, making it extremely difficult to eliminate the defects. The cause of such "sink mark" defects occurring during high-speed winding of the high-speed spinning take-up method is due to the heat generation, elongation, compression, etc. that the yarn receives when winding the polyester yarn into a cheese-like package at high speed. This is because the effects of stress spots become filamentous spots and remain internalized, forming a package cage. Thread unevenness is typified by heat shrinkage characteristics, and causes knitted fabrics to
When heat treated at temperatures above ℃, it appears as "sink marks". Such filamentous spots tend to be concentrated at both ends of the cheese-like package. When forming a package cage, as a result of the traversing caused by the traverse, more yarn is stacked on both ends of the package cage in the bobbin axis direction, creating a so-called selvage shape, and this selvage portion is in contact with the roll of the winding machine. This is thought to be due to contact with. For high-speed winding of 5500 m/min or higher, generally a bobbin shaft drive type winding machine is used, which directly drives a bobbin shaft equipped with a contact roll. The winding mechanism of this bobbin shaft-driven winding machine winds a package formed by laminating yarn on a bobbin with good shape stability while pressing it with a contact roll.
At this time, all the power necessary to rotate the contact roll is transmitted through frictional contact between the package and the contact roll. (This type of contact roll drive system is called a "driven system.") In order to perform high-speed winding with a bobbin shaft-driven winder equipped with such a driven system contact roll, the amount of energy to be transmitted is As a result of the study, it became clear that it is difficult to maintain the normal shape during winding unless the package shape is set at ear height because of the large amount of damage. JP-A-56-127558 proposes winding by forming a bulge in the center of the package and keeping a contact roll in constant contact with the bulge during winding. When winding at a high speed of more than 1 minute, the ends of the package were not properly laminated, making it impossible to form a package. Japanese Patent Application Laid-Open No. 60-209013 discloses that a conventional bobbin shaft-driven winding machine for producing a cheese-like package
It is mentioned that it is difficult to eliminate thread unevenness due to the provision of contact rolls, and as an alternative, it is proposed that the package cage be wound in a tapered shape without coming into contact with other objects during winding. . Therefore, without melt spinning and stretching
It is a cheese-like package that is wound at a high speed of 5,500 m/min or more, and has good shape stability, and the yarn is directly applied to the knitted fabric from the package and can be wound at normal pressure to
At present, no method has yet been found for producing cheese-like packages made of polyester fiber yarns that do not cause "sink" defects even when dyed at 110°C. The present invention provides easy-to-dye and low-heat-shrinkable polyester yarn produced by a high-speed spinning draw method.
It has good shape stability and can be directly applied to knitted fabrics.
The object of the present invention is to provide a method for producing a polyester yarn package, which can yield knitted fabrics of good quality that do not cause "sink" defects even when dyed at normal pressure to 110°C. [Means for Solving the Problems] As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention have found that thread unevenness that causes "sink marks" has been determined by the winding method of the cheese-like package and the package By focusing on the fact that it is deeply related to the shape of the package, and by making the yarn into a specific package shape, we can reduce sink marks.
The above problem has been solved by discovering the fact that it can be completely resolved. That is, an object of the present invention is to wind a melt-spun polyester yarn into a cheese-like package using a spindle-driven winder at a speed of 5,500 m/min or more without drawing, using a self-driven contact roll and a yarn. During winding, a winding machine equipped with a multi-track traverse that can reverse the traversing of the package in the direction of the bobbin axis by 2 mm or more toward the center from the ends to form a part with higher hardness than the ends. This is achieved by a method for manufacturing a polyester yarn package, which is characterized in that winding is carried out at a contact pressure of 0.2 kg/package stroke of 1 cm or less. The high-speed winding referred to in the present invention means that the spinning/winding speed is
A method for winding polyester yarn at a speed of 5,500 m/min or more, typically using a spinning method that does not use a godet roll as disclosed in Japanese Patent Application Laid-Open No. 57-121613, etc., or a method for winding a melt-spun polyester yarn using a godet roll. It is applicable to a method of winding onto a bobbin without substantially stretching. Therefore, the yarn of the package obtained by the method of the present invention is untwisted and is distinguished from yarn that is untwisted by winding or the like. The term "polyester" used in the present invention refers to polyesters represented by polyethylene terephthalate, polybutylene terephthalate, etc., but a small amount of other polyesters may be added as long as the easy dyeability and dimensional stability, which are the characteristics of the yarn of the present invention, are not impaired. It may also contain polymeric components, stabilizers, antistatic agents, and the like. A polyester yarn obtained by melt-spinning polyester and winding it by the method of the present invention without drawing at a speed of 5500 m/min or more has a birefringence of 0.08 to 0.14, a crystalline perfection parameter of 0.50 or less, and a boiling water shrinkage rate of 5% or less. It has structural features that If the birefringence is less than 0.08, the mechanical properties such as strength and elongation cannot be sufficient to allow the wound package to be directly used as a knitted fabric without going through post-processes such as stretching. If the birefringence index is 0.14 or more, the easy dyeability that is a characteristic of high-speed spun drawn yarn cannot be sufficiently obtained. In addition, the crystal perfection parameter is an index indicating the structure of the crystal part measured by the method described below. becomes good. The crystal perfection parameter of the polyester yarn obtained by winding according to the present invention is 0.50 or less, and as a result, it has excellent low heat shrinkage with a boiling water shrinkage rate of 5% or less. DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings showing one embodiment of the present invention. The cheese-like package of polyester yarn obtained by the winding method of the present invention has a portion (hereinafter referred to as a convex portion) that is harder than the end portions from both ends of the package toward the center of the bobbin axis. ) is present in multiple locations. The convex portion is a bulge 5 that exists on a line parallel to the bobbin axis direction of the package 1, as illustrated in the cross-sectional view of the package in FIG. 1, and has a winding diameter slightly larger than the other portions. The filaments are layered to look like this. The winding diameter difference Δh is preferably about 0.2 mm to 3 mm from the viewpoint of winding shape stability. More preferably, about 0.2 to
It is 1mm. Such a convex portion 5 exists from both ends 2 of the package cage 1 toward the center in the bobbin axial direction, but if the position from both ends ( ₁ , ₂ in Fig. 1) is 2 mm or more, it is considered a "sink mark." It is preferable in terms of the elimination effect. For the purpose of maintaining good shape stability during and after high-speed winding, this position is more preferably 4 mm to 15 mm. The positions from both end portions 2 do not necessarily have to be the same on the left and right, but in consideration of ease of traversal, the same position ( ₁ = ₂ ) is usually adopted. The convex portion 5 needs to be formed with a higher hardness than both ends 2 (ear portions) of the package. By making the hardness higher than both ends, both ends 2
By weakening the tension of the threads and promoting the effect of relaxing the threads at both ends after winding, it is possible to eliminate "sink marks." A desirable hardness difference between the end of the package and the convex portion is 5° to 20°. The package obtained by the winding method of the present invention has a unique hardness distribution in which the highest hardness part exists in the bobbin axial direction other than at both ends.
Easily distinguishable from conventional high-ear package. The convex portions are provided at a plurality of locations on the central portion side of the package in the bobbin axial direction for the purpose of improving shape stability. Usually, there are two to three locations, preferably two locations, considering the complexity of the traverse mechanism. The above-described unique winding shape is such that the packages are laminated almost constantly from the beginning of winding to the end of winding. As a result, it is possible to have extremely good winding shape stability even when winding a large amount of winding, not only several kilograms but also tens of kilograms. In addition to the above-mentioned winding shape, the cheese-like package obtained by the winding method of the present invention has a difference in dry heat shrinkage stress value between the yarn in the hard part and the yarn in other parts. The second feature is that it is 30 mg/d or less. As a result of various in-depth studies on the relationship between the occurrence of "sink mark" defects and the unevenness of the thread quality of the yarn of the package cage, the present inventors found that the unevenness of the dry heat shrinkage stress value of the yarn of the package cage in the yarn length direction is " It was found that this corresponds well to the occurrence of sink marks. As a result of further investigation, it was found that the yarn in the contact area between the package cage and the contact roll during winding tends to have a higher dry heat shrinkage stress value than the yarn in the non-contact area, and this stress value difference exists. If it is less than the value,
It was discovered that "sink marks" do not occur. The package obtained by the winding method of the present invention has a dry heat shrinkage stress value difference of 30 mg between the yarn in the high hardness part (convex part) and the yarn in other parts, as measured by the method described below. /d or less. In order to further reduce "sink marks", the amount is preferably 20 mg/d or less, more preferably 15 mg/d or less. The high-selvedge package obtained by the conventional winding method is
The feature of the package of the present invention is clear from the fact that the difference in dry heat shrinkage stress value between the yarn at the high end and other parts cannot be less than 40 mg/d. Such heat shrinkage stress characteristics are satisfied from the beginning to the end of winding the package. The winding method of the present invention will be described below. The above-mentioned cheese yarn packages were first made possible to be stably and efficiently obtained by winding the yarn using a bobbin shaft-driven winder equipped with a specific traverse mechanism and a self-driven contact roll. . In other words, the method of providing a convex portion from both ends of the package cage to the center side in the bobbin axial direction is described in Japanese Patent Publication No. 46
-A multi-speed traverse device disclosed in Publication No. 16298 or a known cam traverse device is used to reverse the traversing of the yarn by traversing even inside the end in the bobbin axis direction of the package, so that the yarn is harder than the end. This can be effectively achieved by employing a so-called multi-tract traverse that can form a portion with a high surface area. Considering the complexity of the traverse mechanism, the position of the convex portion, the ease of adjusting the amount of stacked yarn, etc., it is most preferable to adopt a multi-tract traverse system using a cam. The multi-track traverse is a method in which the traverse is reversed not only at both ends but also at the center, as exemplified in FIGS. 2a and b, and the desired position, It is possible to provide a height protrusion. Figure 2a
are examples of two-track traversal, Fig. 2b and c.
is an example of a three-track traverse, and Figure 2 d
is an example of a traverse that is a conventional high-selvedge package other than the present invention. A method of forming the convex portion closer to the center than the ends in the bobbin axial direction using this multi-track traverse as illustrated in FIG. 1 will be explained using the three-track example shown in FIG. 2b. The yarn to be traversed is stacked at the end as a package yarn in the first and second reversals, and then in the following three
In the second reversal, the threads are stacked closer to the center than the ends. At this time, the radius R at the time of reversal, R,
By selecting the ratio of R, the height of the convex portion formed closer to the center than the end can be adjusted. The package of the present invention can be obtained if the number of tracks is 2 or more, but 2 to 4 is usually employed. The present invention combines the above-mentioned traverse mechanism with a self-driven contact roll for winding.
For the first time, winding of the package is realized. With the combination of the conventional driven contact roll and the above-mentioned traverse mechanism, the shape of the package collapses during winding, making normal winding difficult. FIG. 3 shows an embodiment showing the configuration of main parts of a winding machine used in the method of the present invention, in which the bobbin shaft 8 is connected to a bobbin shaft drive device 12, and is further connected to a bobbin shaft drive inverter 13. , is driven while controlling the frequency so that the surface peripheral speed of the package 1 wound on the surface of the bobbin 7 inserted into the bobbin shaft 8 is constant. The contact roll 6 is connected via a transmission device 9 to
It is connected to a contact roll drive device 10, and is further supplied with the frequency and driving force necessary to rotate the contact roll 6 at a speed corresponding to the surface circumferential speed of the package 1 by a contact roll drive inverter 11. The drive inverter for the bobbin shaft and the drive inverter for the contact roll may be mutually adjustable mechanisms as shown in Japanese Patent Application Laid-Open No. 52-21438, but from the point of view of eliminating "sink marks" more completely, It is preferable that both drive inverters are controlled independently of each other so that the speed of the contact rolls can be controlled with high precision. In this case, as a control method to gradually reduce the bobbin shaft rotation speed as the winding diameter of the package increases, a method is used in which the gradual reduction speed is stored in a computer and controlled.
Tension control method detects changes in the tension applied to the yarn and feeds it back to the bobbin shaft for control. Circumferential speed uses an optical sensor to detect changes in the peripheral speed of the contact roll or winding body and controls it by feeding it back to the bobbin shaft. Control methods etc. will be adopted. The contact roll drive 9 used in the winder of the method of the invention preferably uses a high speed three-phase induction motor. The connection method of this motor is not limited to the embodiment, and it may be directly connected to the shaft of the contact roll, or it may be built into the contact roll and implemented as an outer rotor type. Furthermore, it is also possible to use an air turbine drive instead of a motor. The driving force supplied to drive the contact roll is determined by the circumferential speed of the contact roll measured without winding and in a non-contact state with the bobbin shaft, and the desired circumferential speed of the package (winding speed) is the same speed
When it is set as 100%, the object of the present invention can be sufficiently achieved if it is 75% to 125%. Usually 100% is accepted. (Hereinafter, 100% is shown unless specified.) However, regarding the frequency, 0 to 10% is calculated based on the set winding speed.
It should be set within a range exceeding %. FIG. 4a is a schematic diagram showing the contact state of the cheese-like package of the present invention with a contact roll during winding. For comparison, FIG. 4b shows a contact state between a conventional high-end package and a contact roll. In the winding method of the present invention, the winding contact pressure when winding is performed by the winding machine is 0.3, which is normally employed.
Kg/package 0.2Kg/per 1cm of cage stroke
It is necessary to wind the package with a stroke of 1 cm or less. To further improve quality,
It is preferable to carry out the test at 0.15 kg/package stroke of 1 cm or less. By adopting the self-driven contact roll of the present invention, it is possible to perform winding at an even lower 0.1 kg/package stroke of 1 cm, and this low contact pressure enables extremely good winding shape stability and the elimination of "sink marks". It became. Conditions such as winding tension and winding angle are within the range adopted for normal winding. By adopting the winding method of the present invention, shape stability can be achieved when winding easily dyeable and low heat shrinkable polyester fibers manufactured at high speeds of 5,500 m/min or higher without drawing after melt spinning. It has now become possible to produce a cheese-like package that is of good quality and does not cause any "sink" defects even when it is directly applied to the knitted fabric and dyed at normal pressure to 110°C. According to the findings of the present inventors, even when the energy propagates through the contact portion between the package cage and the contact roll during high-speed winding,
Multi-tract traverse, which has become so small that it has become possible for the first time to form a package cage even if it is not at ear height, allows the position, height, etc. of the convex part to be formed inside the edge of the package to be formed accurately and reproducibly. It became. It is assumed that this is achieved by enabling low contact pressure winding, minimizing the stress applied to the fibers at the contact area between the package cage and the contact roll, eliminating yarn unevenness, and eliminating "sink marks". be done. [Example] Hereinafter, the present invention will be explained in more detail with reference to Examples. In addition, in the examples, the evaluation method of each characteristic value used is as follows.・Dry heat shrinkage stress value: Thermal stress measuring device KE− manufactured by Kanebo Engineering Co., Ltd.
Using type 2, the sample length is 10 cm as a loop, and the initial load is 10
mg/d, the temperature was raised at a heating rate of 150° C./min, and a dry heat shrinkage stress curve was drawn. The maximum value of this curve (the value obtained by dividing the read value by the sample denier x 2) was taken as the dry heat shrinkage stress value (Fmg/d). The dry heat shrinkage stress value difference in the yarn length direction is determined by measuring the yarn of the package by making sure that the convex part is measured.
Thermal stress values are measured at several points (for example, 7 to 8 points when the yarn length of one traverse is 1.5 m) in the traverse direction (from one end to the other end).
This measurement was performed for 5 traverses. Based on the obtained measurement results, the average value of the dry heat shrinkage stress value of the convex part is calculated.
₁ mg/d, and among the measured values other than the convex portions, the same number of values as the convex portions were extracted starting from the smallest value, and the average value was determined and set as ₂ mg/d. The dry heat shrinkage stress value difference in the yarn length direction was determined using the following formula. Dry heat shrinkage stress difference (ΔF) = ₁ − ₂ (mg/d) ・Hardness Using Shimadzu HARDNESS TESTER, measure the circumference across the diameter of the package cage at the end and the convex part in the bobbin axis direction of the package cage. 8 in the direction
The hardness of the equally divided positions was measured. n for each
The average value of =8 was determined, and the difference was defined as the hardness difference.・ Birefringence Δn Using a transmission quantitative interference microscope (manufactured by Karl Zeiss Jena, East Germany), the refractive index parallel to the fiber axis was determined using green light (wavelength 549 mμ) using the interference fringe method.
Measure the refractive index n ₁ perpendicular to n ₁₁ , and find the birefringence Δn=
It was determined by n ₁₁ −n ₁ .・Crystal perfection parameter C _R Using an X-ray diffraction device, the sample thickness of the raw thread was 0.5 mm
A diffraction intensity curve from 2θ of 7° to 35° was drawn under the following conditions. 30kV, 80mA, scanning speed 1°/min, chart speed 10m/min, time constant 1 second, receiving slit 0.3mm. The three main reflections drawn in the range of 2θ = 17° to 26° are designated (100), (010), and (110) from the low angle side. The diffraction intensity curves between 2θ = 7° and 35° are connected with a straight line to form the baseline. A perpendicular line is drawn between each peak and the baseline, and this perpendicular line is taken as the diffraction intensity.
Let the diffraction intensity at the point corresponding to the valley between (010) and (110) be I ₀ , and the diffraction intensity at the peak of (110) be I
Then, the crystal perfection parameter C _R is expressed by the following equation. C _R = I ₀ / I ・ Boiling water shrinkage rate L _{= 0} sample length under a load of 0.1 g/d, the load was removed, the sample was treated in boiling water for 30 minutes, and the length measured under the same load was L. The shrinkage rate of boiling water is expressed by the following formula: Boiling water shrinkage rate (%) = L ₀ - L / L ₀ × 100 ・ Dyeability Polyester yarn was dyed using disperse dye Resolin Blue FBL (trade name of Bayer), 3% owf, bath ratio 1 The staining rate was calculated by staining at 100° C. for 120 minutes at a ratio of 50% and measuring the absorbance of the dye solution after staining. A dyeing rate of 60% or more indicates good dyeability, and a dyeing rate of 70% or more allows dyeing under normal pressure, which is extremely good. - Display of weft "sink marks" Defect levels were divided into four levels, and W = 0 to 1 were considered to be acceptable. W=0: No sink mark at all, W=1: Very slight sink mark W=2: Sink mark, W=3: Strong sink mark Example 1 Melt spinning polyethylene terephthalate with intrinsic viscosity [η]=0.60 at 300°C After cooling, all the filaments are collected at a position 20 cm below the thinning completion point, oiled, and made into a 75 _d / 36 _f thread without drawing.
Winding with a winder at a speed of 7500 m/min, winding amount 10
Kg of cheese-like packages were obtained. The physical properties of the yarn were as shown in the table below.

[Table] When winding, a spindle-driven winding machine equipped with a self-driven contact roll shown in Figure 3 is used, and a winding machine equipped with a three-track traverse type cam traverse shown in Figure 2b is used. there was. The reversal radius (R) of the yarn by traverse is R ₁ , R ₂ = 20 mm for the yarn, R ₃ = 15 mm for the yarn,
Packages were obtained by varying the distance between the yarns and the reversal positions of the yarns as shown in Table 1. For comparison, winding was performed using the conventional one-track traverse shown in FIG. 2d. In this example, the following conditions were used, except that the winding contact pressure was 0.15 kg/package stroke 1 cm. Bobbin outer diameter: 140mmφ Traverse stroke: 160mm Winding tension: 0.25g/d Winding winding angle: 6° Self-driving contact roll control method: Peripheral speed control method Driving force: 100% Next, from these packages, the yarn is Directly pour the entire amount of water into the Nissan water jet room (LW
-51 type) for weaving, warp density 100 strands/in,
It was made of plain woven fabric with a weft density of 80 threads/in. After refining this plain woven fabric, it is made without presetting.
It was stained at 100℃ and the quality of the weft "sink mark" was determined. Table 1 shows the shape stability when winding the cheese-like package and the shape characteristics of the 10Kg package.
The difference in heat shrinkage stress value (ΔF) of the surface layer portion and the corresponding fabric quality are shown.

[Table] As is clear from Table 1, the cheese-like package obtained by the winding method of the present invention has good winding shape stability and can be used directly on the weft of a fabric and dyed under normal pressure. It was possible to obtain excellent dyeability and good quality. Comparative Example In the same spinning and winding as in Example 1, the multi-tract traverse used in Example 1 was added using a spindle-driven winder attached to a conventional driven contact roll that does not have self-driving force. I tried winding it using a winder. The interval between the reversal positions of the traverse is 3 mm and 5 mm.
I tried winding the seeds, but from the beginning of the winding, the amount of yarn was about approx.
After stacking 0.5 kg, the shape collapsed and it was difficult to continue winding. Next, a 10 kg cheese-like package was obtained using a winding machine in which this driven contact roll was combined with a conventional traverse mechanism shown in FIG. 2d under the same conditions as in Example 1. However, the dry heat shrinkage stress value variation (ΔF) of this package was as large as 60 mg/d, and the quality of the fabric was extremely poor, with a weft "sink mark" W=3. Example 2 In Example 1, the traverse reversal position is set to No.
The same conditions were used except that the winding was carried out under the conditions shown in Table 2, and the shape stability and the occurrence of weft "sink marks" due to dyeing at 100° C. were examined.

[Table] According to the present invention, 0.2Kg/package stroke 1cm or less, and further 0.15Kg/package stroke
Winding was possible even with a low contact pressure of less than cm, and a fabric of extremely good quality was obtained. Example 3 Polyethylene terephthalate with an intrinsic viscosity [η] = 0.61 was melt-spun at 295°C, and after cooling, it was spun with a pair of unheated godet rolls at the same circumferential speed and spun at 75 ^d /36 ^f without stretching. The yarn was wound at the speed shown in Table 3 to obtain a cheese-like package with a winding weight of 12 kg. For winding, a winding machine equipped with a self-driven contact roll shown in FIG. 3 and a two-track traverse type cam traverse shown in FIG. 2d was used. The reversal radius of the yarn (,) by traverse is R ₁ = 40 mm, R ₂ = 15 mm,
The interval between the reversal positions was set to 4 mm. Other conditions were the same as in Example 1 to obtain a package. The positions of the convex portions of the obtained cheese-like packages from the ends were all 4 mm ( ₁ = ₂ ), and the shape stability during winding was also good. The physical properties of the obtained yarn, the shape of the 12 kg package, the dry heat shrinkage stress value difference (ΔF) of the surface layer, and the weft "sink mark" of the fabric after dyeing at 100°C obtained in the same manner as in Example 1. The quality is shown in Table 3. As is clear from Table 3, the cheese-like package obtained by the winding method of the present invention has good winding shape stability and can be used directly on the weft of a fabric.
It was dyed under normal pressure and had good dyeing properties and no weft "sink marks".

〔Effect of the invention〕

Since the method for producing a yarn package according to the present invention is configured as described above, the cheese-like package of thermoplastic synthetic fibers obtained by the winding method has good shape stability and the yarn can be directly applied to the package. The knitted fabric obtained by using it for knitting and weaving and dyeing it at normal pressure to 110°C can be of good quality and easy to dye.
Particularly, special effects are exhibited when used as the warp and weft of textiles. The winding method of the present invention exhibits even more remarkable effects when the winding speed is 6,000 m/min, particularly at a high speed of 7,000 m/min or higher.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of the shape of a cheese-like package obtained by the winding method of the present invention, and FIG. FIG. 3 is a perspective view showing the mechanism of a winding machine equipped with a self-driven contact roll, and FIG. 4 is a schematic diagram showing the state of contact between the contact roll and the package during winding of the package.
A indicates the present invention, and b indicates the conventional example. DESCRIPTION OF SYMBOLS 1...Cheese-like package, 2...Package end, 3...Trajectory of reversal of yarn, 4...Fiber, 5
...Protrusion, 6...Contact roll, 7...Bobbin, 1
0...Contact roll drive device, 12...Bobbin shaft drive device.

Claims (1)

[Claims] 1. When winding a melt-spun polyester yarn as a cheese yarn package using a spindle-driven winder at a speed of 5500 m/min or more without drawing, a self-driven contact roll and a yarn During winding, a winding machine equipped with a multi-track traverse that can reverse the traversing of the package in the direction of the bobbin axis by 2 mm or more toward the center from the ends to form a part with higher hardness than the ends. A method for manufacturing a polyester yarn package, characterized in that winding is carried out at a contact pressure of 0.2 kg/package stroke of 1 cm or less. 2. Production of a polyester yarn package according to claim 1, characterized in that a winding machine is used in which the circumferential speed control mechanism of the self-driven contact roll and the circumferential speed control mechanism of the bobbin shaft are independent from each other. Method.