Yarn package and method of manufacturing the same

Abstract

The present invention provides a yarn package and a manufacturing method thereof, which do not easily cause problems such as edge separation and collapse during unrolling, even if the wound yarn is a multifilament yarn or a ribbon yarn. When a multifilament yarn or a ribbon yarn having a total fineness of 100 dtex to 6400 dtex per one is wound in a plurality of turns on a bobbin (2) to manufacture a yarn package (1), each yarn constituting a yarn layer (3) is arranged at intervals from each other and wound in such a manner that a reciprocating width w is the same in each yarn and a reciprocating reversal position is changed according to each yarn.

Description

Technical Field

[0001] The present invention relates to a yarn package in which a yarn is wound around a bobbin and a method for manufacturing the same. More specifically, it relates to a technique for manufacturing a yarn package by reciprocally winding a multifilament yarn or a ribbon yarn around a bobbin (Japanese: traverse winding). Background Art

[0002] Generally, when winding a strip-shaped or yarn-shaped wire material around a core material such as a bobbin to form a package, reciprocating winding is used in which the wire material is reciprocally wound in the axial direction of the core material. However, in the case of reciprocating winding, the yarn density concentrates at the commutation part, and when forming a package, the both ends in the axial direction of the bobbin are likely to bulge and have a shape protruding compared to the central part.

[0003] In the case of a package having a shape with bulging both ends, when unwinding, the wire material may sometimes come off to the outside of the package. If it becomes such a state, problems such as poor feeding or cutting of the wire material caused by snagging or winding may occur during unwinding. The winding collapse (Japanese: 巻き崩れ) of such a package is more significant when the thickness of the wire material is thicker, and in the case of general synthetic fibers, it is common for synthetic fibers having a total fineness of 100 dtex or more per strand or a size thickness equivalent thereto, and when the total fineness per strand reaches 1000 dtex or more, winding collapse occurs significantly.

[0004] As a method for preventing the bulging of both ends, there is a method of increasing the pressing pressure (contact pressure) using a pressure contact roller, but in this method, the yarns in the lower layer at both ends of the yarn layer are pushed out, resulting in a package shape with bulging both end faces, and sometimes it may become a state of "edge drop" (Japanese: 綾落ち) in which the yarn directly falls off from the end while maintaining the wound state. Since the package shape with bulging both ends and the package shape with bulging both end faces have a relationship such that if one is given priority, the other will be significantly manifested, a method of adjusting the conditions to achieve a balance between the two is usually adopted.

[0005] Therefore, a method for unwinding the yarn of an end-high package with bulging ends without causing yarn breakage or the like has been proposed in the past (see Patent Document 1). In addition, a winding method has also been proposed in which the operation of temporarily narrowing the reciprocating width is repeated to prevent the increase in yarn density at both ends of the package (see Patent Documents 2 to Patent Document 4).

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. 2006-240881

[0009] Patent Document 2: Japanese Patent Application Publication No. 11-193179

[0010] Patent Document 3: Japanese Patent Application Publication No. 2000-203761

[0011] Patent Document 4: International Publication No. 2012 / 096040 Summary of the Invention

[0012] The problem the invention aims to solve

[0013] However, the technology described in Patent Document 1 is a technique for resolving malfunctions during unwinding and does not improve poor winding posture during winding. Therefore, even if the device described in Patent Document 1 is used, it is impossible to manufacture a package without bulges at both ends. On the other hand, in the devices described in Patent Documents 2 to 4, in order to prevent bulges at both ends of the package, the reciprocating width is adjusted by changing the distance between the spool and the pressure roller, and winding is performed. However, in this method, it is impossible to accurately reverse the reciprocating position at the desired reversing position.

[0014] In particular, when winding up yarns with a fineness of several thousand dtex, similar to synthetic fibers, malfunctions are prone to occur during winding because the coarser yarns are wound up overlapping each other at the reciprocating reverse position. Furthermore, the technologies described in Patent Documents 2 to 4 require additional control equipment, thus complicating the device and increasing its cost.

[0015] Therefore, the present invention provides a yarn package and its manufacturing method that are not prone to problems such as edge stripping or collapse during winding, even if the wound yarn is a multifilament yarn or a ribbon yarn.

[0016] Solution for solving the problem

[0017] The yarn package of the present invention comprises: a bobbin; and a yarn layer formed by winding multiple multifilament yarns or ribbon yarns on the bobbin in a reciprocating manner at intervals. The total fineness of each of the multifilament yarns and the ribbon yarns is 100 dtex to 6400 dtex. The reciprocating width of each yarn wound on the bobbin is the same, but the reverse positions are different.

[0018] Alternatively, in the yarn layer, the number of yarns wound at both ends in the axial direction is less than the number of yarns wound in the central part in the axial direction, and one or more steps are formed at both ends in the axial direction.

[0019] The method for manufacturing the yarn package of the present invention includes a winding process in which multiple multifilament yarns or ribbon yarns with a total fineness of 100 dtex to 6400 dtex are wound onto a spool in a reciprocating manner at intervals. In the winding process, the reciprocating width is the same for each yarn, and the reversing position changes according to each yarn.

[0020] In the winding process, the number of yarns wound at both ends in the axial direction is less than the number of yarns wound at the center in the axial direction, and one or more steps are formed at both ends in the axial direction of the yarn layer formed on the bobbin.

[0021] In this case, for example, a reciprocating guide with m or more slots (m is a natural number greater than 2) can be used to simultaneously wind m of the multifilament yarns or the ribbon yarns.

[0022] At this time, the spacing between the slots of the reciprocating guide can be set to, for example, 0.3mm to 5mm.

[0023] The effects of the invention

[0024] According to the present invention, since the number of yarns wound at both ends in the axial direction is reduced, even if the wound yarn is a multifilament yarn or a ribbon yarn, a yarn package can be obtained that does not bulge at both ends and is not prone to problems such as edge stripping or collapse during winding. Attached Figure Description

[0025] Figure 1 This is a side view showing the external shape of the yarn package according to the first embodiment of the present invention.

[0026] Figure 2 It means Figure 1 A schematic diagram showing the winding state of the two ends of the yarn package 1.

[0027] Figure 3 A is a schematic diagram representing the cross-section of multifilament yarn. Figure 3 B is a schematic diagram representing the cross-section of the strip yarn.

[0028] Figure 4 This is a cross-sectional view showing an example of the structure of composite fibers (monofibers) used in multifilament yarns or ribbon yarns. Figure 4 A is a core-skin composite type. Figure 4 Type B is an eccentric core type. Figure 4 C is a parallel type.

[0029] Figure 5 It is a schematic representation Figure 1 A diagram illustrating the manufacturing method of the yarn package 1 shown.

[0030] Figure 6 A, Figure 6 Figure B is an example of the groove shape of a reciprocating guide.

[0031] Figure 7 This is a side view showing the external shape of a yarn package according to a modified example of the first embodiment of the present invention.

[0032] Figure 8 This is a diagram schematically illustrating a yarn roll-out test method according to an embodiment of the present invention. Detailed Implementation

[0033] Hereinafter, the embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described below.

[0034] (First Embodiment)

[0035] First, the yarn package of the first embodiment of the present invention will be described. Figure 1 This is a side view showing the external shape of the yarn package according to this embodiment. Figure 2 This is a schematic diagram showing the winding state of both ends of the yarn package in this embodiment. (Example) Figure 1 and Figure 2 As shown, the yarn package 1 of this embodiment is formed by a bobbin 2 and a yarn layer 3 formed on the bobbin 2.

[0036] [Spool 2]

[0037] The spool 2 can be a cylindrical object made of paper, plastic, or metal such as aluminum alloy. There is no particular limitation on the size of the spool 2, and it can be appropriately set according to the length, thickness, and material of the yarn being wound.

[0038] [Yarn Layer 3]

[0039] The yarn layer 3 is formed by repeatedly winding multiple yarns 31a and 31b onto the bobbin 2. The yarns 31a and 31b constituting the yarn layer 3 are multifilament yarns or ribbon yarns formed from dozens to hundreds of single fibers. As for the single fibers, for example, composite fibers formed from two thermoplastic resins with different melting points can be used. Figure 3 A is a schematic diagram representing the cross-section of multifilament yarn. Figure 3 B is a schematic diagram representing the cross-section of the ribbon yarn. Furthermore, Figure 4 This is a cross-sectional view showing an example of the construction of composite fibers (monofibers) used in multifilament yarns and ribbon yarns. Figure 4 A is a core-skin type. Figure 4 Type B is an eccentric core type. Figure 4 C is a parallel type.

[0040] like Figure 3 As shown in A, "multifilament yarn" is formed by twisting multiple single fibers such as composite fibers 32a, 32b, and 32c together to form a single yarn (bundle). Composite fibers 32a, 32b, and 32c are formed from a first resin component (hereinafter referred to as the low-melting-point component 33) and a second resin component (hereinafter referred to as the high-melting-point component 34) with a melting point at least 20°C higher than that of the first resin component. Figure 4 The core-sheath type composite fiber 32a shown in A and Figure 4 In the case of the eccentric core-sheath type composite fiber 32b shown in B, the sheath is formed by low melting point component 33 and the core is formed by high melting point component 34.

[0041] On the other hand, "ribbon yarn" is formed by bonding together composite fibers such as 32a, 32b, and 32c into a single yarn. For example, in the use of... Figure 4 The core-sheath type composite fiber 33a shown in A, Figure 4 When the eccentric core-sheath type composite fiber 33b shown in B is used as a single fiber, such as Figure 3 As shown in B, the structure consists of a sea area formed by low-melting-point component 33 and an island area formed by high-melting-point component 34. Furthermore, the single fibers constituting the multifilament yarn and ribbon yarn are not limited to the aforementioned composite fibers; single fibers formed from a single resin can be used, or a mixture of single fibers and composite fibers can be used. In addition, composite fibers can also be used in the manner of multi-core composite fibers, etc. Figure 4 A~ Figure 4 The structure other than the structure shown in C.

[0042] From the perspective of the magnitude of the effect and practicality, it is preferable that the multifilament yarn and ribbon yarn used in the yarn package of this embodiment have a total fineness of 100 dtex to 6400 dtex per yarn. When the total fineness of each yarn is less than 100 dtex, the ends are less likely to bulge, thus reducing the advantages of applying the present invention. On the other hand, yarns with a total fineness greater than 6400 dtex have fewer applications. Furthermore, with such high-fineness yarns, the wound yarn is prone to collapse or overlap at the ends, thus easily resulting in a poor winding posture that differs from the bulges at both ends.

[0043] like Figure 2As shown, in the yarn package 1 of this embodiment, in order to prevent the aforementioned yarns (multifilament yarns or ribbon yarns) 31a and 31b from crossing or overlapping each other, the yarns are wound approximately parallel to each other at intervals. Furthermore, the reciprocating width w of each yarn 31a and 31b constituting the yarn layer 3 is the same, but their reciprocating positions are different. Only yarn 31a or yarn 31b is wound at the x-axis ends of the yarn layer 3. As a result, in the yarn layer 3, the number of yarns wound at both ends in the x-axis direction is less than the number of yarns wound at the center in the x-axis direction, and a lower outer step 3a is formed at both ends in the x-axis direction.

[0044] Here, the "steps" formed at both ends of the yarn layer 3 are created by making the diameter of the two ends in the x-axis direction smaller than the diameter of the central part in the x-axis direction, as long as the difference can be seen at the position of the outer surface in the side view. In addition, the shape of the corner of the step 3a varies depending on the shape and state of the wound yarn, and it does not have to be made into a right angle, but can be curved or have the side tilted.

[0045] [Manufacturing Method]

[0046] Next, the manufacturing method of the aforementioned yarn package 1 will be described. Figure 5 It is a schematic representation Figure 1 A diagram illustrating the manufacturing method of the yarn package 1 shown. Figure 6 A and Figure 6 B represents Figure 5 A diagram showing an example of the groove shape of the reciprocating guide 5. (See diagram for example.) Figure 5 As shown, when manufacturing the yarn package 1 of this embodiment, multifilament yarn or ribbon yarn is wound onto the bobbin 2 to form a yarn layer 3.

[0047] In the manufacturing method of the yarn package 1 of this embodiment, during the winding process, the number of yarns wound around both ends of the x-axis is less than the number of yarns wound around the central portion of the x-axis, and one or more steps 3a are formed at both ends of the yarn layer 3 in the x-axis direction. Specifically, multiple multifilament yarns or ribbon yarns are arranged at intervals and wound onto the bobbin 2 in such a way that the reciprocating width w is the same in each yarn strip, and the reciprocating position changes according to each yarn strip.

[0048] In this case, when the number of multifilament yarns or ribbon yarns wound simultaneously is m (m is a natural number greater than 2), a reciprocating guide with m or more grooves is used. For example, in... Figure 5 When winding two yarns (multifilament yarns or ribbon yarns) 31a and 31b, as shown, a reciprocating guide 5 with two or more grooves 5a is used for winding. This ensures a predetermined interval and stable winding of multiple yarns.

[0049] Furthermore, the groove shape of the reciprocating guide 5 is not limited to Figure 6 The shape shown in Figure A, 5a, which is rectangular in side view, could also be... Figure 6 The side view of groove 5b, as shown in Figure B, is U-shaped, which can be appropriately selected according to the material and characteristics of the yarn. Furthermore, considering the strength of the reciprocating guide 5, it is preferable to set the length of the partition wall separating each groove 5a, 5b, i.e., the interval between adjacent grooves 5a or 5b, to be 0.3 mm or more. Considering the prevention of yarn slack when the wound yarns are combined for use, it is preferable to set this interval to 5 mm or less.

[0050] Furthermore, in order to suppress the effects of damage during reciprocating motion on the yarn, it is preferable that the grooves 5a and 5b of the reciprocating guide 5 have a certain depth (length) in the direction of yarn travel. Additionally, the material of the reciprocating guide 5 is not particularly limited, but from the perspective of wear resistance, it is preferable to use ceramic, stainless steel, or other metallic materials, or materials formed by sintering ceramic onto the surface of a metallic material.

[0051] In this way, by using the reciprocating guide 5 with multiple grooves 5a or 5b formed at predetermined intervals, it is possible to manufacture a yarn package with different reciprocating and reversing positions depending on each yarn in a manner that keeps the setting of the winding width (reciprocating width) of the winding device constant. Furthermore, in the yarn package manufacturing method of this embodiment, the contact pressure between the bobbin 2 generated by the pressure roller 4 and the yarns 31a, 31b does not need to be changed according to the winding position as in the past, and the setting value can be kept constant.

[0052] As detailed above, in the yarn package of this embodiment, multiple yarns are wound around each other at intervals, and the reciprocating width of each yarn constituting the yarn layer is the same, but the reversing position is different. Therefore, for the yarn layer of the yarn package of this embodiment, the number of yarns wound at both ends in the axial direction is less than the number of yarns wound at the center in the axial direction. At both ends in the axial direction, instead of forming a bulge, one or more steps are formed with a lower outer side.

[0053] In the yarn package of this embodiment, since the yarn density is lower at both ends of the yarn layer, even if the wound yarn is multifilament yarn or ribbon yarn, no bulges will occur at both ends, thus suppressing the occurrence of edge slippage, collapse during winding, etc. Furthermore, since the reciprocating width of the yarn package of this embodiment is constant, it is not necessary to add components to the winding device or strictly control the reciprocating width during winding; a yarn package without bulges at both ends can be manufactured using approximately the same operation as in the past.

[0054] (A variation of the first embodiment)

[0055] Next, a modified example of the yarn package according to the first embodiment of the present invention will be described. In the aforementioned first embodiment, an example was given of a package in which two yarns are wound on a spool and a step is provided at both ends of the yarn layer. However, the present invention is not limited to this, and three or more yarns may be wound and two or more steps may be provided at both ends of the yarn layer.

[0056] Figure 7 This is a side view showing the external shape of a yarn package according to a modified example of the first embodiment of the present invention. Figure 7 As shown, in the yarn package 11 of this modified example, three yarns are wound back and forth on the yarn spool 2 at intervals, and steps 13a are formed at both ends of the yarn layer 13 in the x-direction of the axis, which descend outward in two stages.

[0057] The yarn package 11 of this modified example can be manufactured by arranging three multifilament yarns or strip yarns spaced apart from each other and winding them onto the bobbin 2 in such a way that the reciprocating width w is the same in each yarn, and the reciprocating position changes according to each yarn. Thus, two steps 13a are formed at both ends of the yarn layer 13 along the x-axis.

[0058] The yarn package 11 in this modified example is similar to the yarn package of the first embodiment described above. The number of yarns wound at both ends along the x-axis is less than the number of yarns wound at the center along the x-axis. Therefore, the yarn density at both ends of the yarn layer is lower, which can suppress bulging at both ends. As a result, even with multifilament yarns or ribbon yarns, a yarn package that is less prone to edge slippage or collapse during unwinding can be achieved. Furthermore, the structure and effects of this modified example, except as described above, are the same as those of the first embodiment described above.

[0059]

Example

[0060] The effects of the present invention will be specifically illustrated below with examples and comparative examples. In this example, multifilament yarn or ribbon yarn was used to manufacture the yarn package of the first embodiment described above, and its shape and roll-out properties were evaluated. Furthermore, for comparison, the yarn package was manufactured according to conventional methods, and its shape and roll-out properties were evaluated according to the same methods.

[0061] <Example 1>

[0062] (1) Yarn making

[0063] First, ethylene-polypropylene random copolymer (CoPP) with a melting point of 134°C is used for the skin component, and polyethylene terephthalate (PET) with a melting point of 256°C is used for the core component, following the method shown below. Figure 4 The core-sheath type composite fiber shown in A is used to make ribbon yarn.

[0064] Specifically, using a conventional hot-melt composite spinning apparatus and a concentric core-sheath composite nozzle with 120 nozzle orifices, core-sheath composite fibers are spun at a spinning speed (first stretching roller speed) of 66.2 m / min. A fiber-splitting guide separates the 120 monofilaments into two groups of 60 monofilaments each. Next, the stretching temperature is set to 100°C and the stretching speed (second stretching roller speed) is set to 274.0 m / min, resulting in hot stretching between the rollers. Maintaining the same speed, the fibers are brought into contact with a heated Nelson roller at 158°C, causing only the low-melting-point CoPP component to melt, thus integrating the fibers to obtain two ribbon yarns.

[0065] (2) Winding

[0066] Next, using a winding machine including a reciprocating device, the two strip yarns produced according to the aforementioned method are wound onto a spool using a reciprocating guide with two grooves. A paper tube with an outer diameter of 108 mm and a length of 330 mm is used for the winding spool. Furthermore, the groove width of the reciprocating guide is 2.0 mm, and the width of the partition wall (groove spacing) used to separate the grooves is 1.0 mm.

[0067] Then, winding was performed at a winding speed of 275 m / min, with a winding width of 5.044 times per reciprocating width (280 mm). At this time, the winding tension was 0.113 cN / dtex, the contact pressure load applied to the spool (the force of the pressure roller pressing on the winding spool) was 60.76 N, the contact pressure was set to 2.17 N / cm, and the yarn package was wound until the mass of the yarn layer was 4.5 kg, thereby producing the yarn package of Example 1.

[0068] <Example 2>

[0069] The stretching temperature was set to 100°C, and the stretching speed (speed of the second stretching roller) was set to 274.0 m / min. The core-sheath composite fiber, obtained by spinning with the same materials, methods, and conditions as in Example 1, was hot-stretched between rollers. It was then brought into contact with a heated Nelson roller at 120°C while maintaining the same speed, resulting in two bundles of multifilament yarns. These two bundles of multifilament yarns were then wound onto a spool (paper tube) using the same methods and conditions as in Example 1, thus obtaining the yarn package of Example 2.

[0070] <Example 3>

[0071] Using the same materials as in Example 1, the resin ejection rate of the hot-melt composite spinning device relative to the core was set to four times that of Example 1 in the spinning process. A core-sheath composite fiber was spun using a core-sheath concentric composite nozzle with 480 nozzle holes at a spinning speed (first stretching roller speed) of 66.2 m / min. The 480 monofilaments were then divided into two groups of 240 monofilaments each using a fiber-separating guide, with other conditions identical to those in Example 1, resulting in two ribbon yarns. Using a reciprocating guide with two grooves, a groove width of 5.0 mm, and a groove spacing of 1.0 mm, the two ribbon yarns were wound onto a spool (paper tube) using the same method and conditions as in Example 1, resulting in the yarn package of Example 3.

[0072] <Example 4>

[0073] Using the same materials as in Example 1, the resin ejection amount of the hot melt composite spinning device relative to the core was set to 1 / 4 of that in Example 1 during the spinning process. Otherwise, two strip yarns were produced using the same methods and conditions as in Example 1. A reciprocating guide with 2 grooves, a groove width of 0.3 mm, and a groove spacing of 1.0 mm was used. Otherwise, the two strip yarns were wound onto a bobbin (paper tube) using the same methods and conditions as in Example 1, thereby obtaining the yarn package of Example 4.

[0074] <Example 5>

[0075] Using a reciprocating guide with 2 slots, a slot width of 2.0 mm, and a partition wall width (slot interval) of 5.0 mm separating the slots, two strip yarns made with the same materials, methods, and conditions as in Example 1 are wound onto a spool (paper tube) to obtain the yarn package of Example 5.

[0076] <Example 6>

[0077] Using a reciprocating guide with 2 slots, a slot width of 2.0 mm, and a partition wall width (slot interval) of 0.3 mm separating the slots, two strip yarns made with the same materials, methods, and conditions as in Example 1 are wound onto a spool (paper tube) to obtain the yarn package of Example 6.

[0078] <Example 7>

[0079] Using the same materials as in Example 1, the resin ejection rate of the hot melt composite spinning device relative to the core was set to 1.5 times that of Example 1 in the spinning process. The 120 monofilaments were divided into three groups of 40 monofilaments each using a fiber-separating guide. Otherwise, three strip yarns were produced using the same method and conditions as in Example 1. Using a reciprocating guide with 3 grooves, a groove width of 2.0 mm, and a groove spacing of 1.0 mm, the three strip yarns were wound onto a bobbin (paper tube) using the same method and conditions as in Example 1, thereby obtaining the yarn package of Example 7.

[0080] <Example 8>

[0081] Using the same materials as in Example 1, the resin ejection rate of the hot melt composite spinning device relative to the core was set to 2.5 times that of Example 1 in the spinning process. The 120 monofilaments were divided into five groups of 24 monofilaments each using a fiber-separating guide. Otherwise, five strip yarns were produced using the same method and conditions as in Example 1. Using a reciprocating guide with 5 grooves, a groove width of 2.0 mm, and a groove spacing of 1.0 mm, the five strip yarns were wound onto a bobbin (paper tube) using the same method and conditions as in Example 1 to obtain the yarn package of Example 8.

[0082] <Example 9>

[0083] Using the same materials as in Example 1, the resin ejection rate of the hot melt composite spinning device relative to the core was set to 8 times that of Example 1 in the spinning process. A composite nozzle with 480 nozzle holes and a core-shell concentric type was used. The 480 monofilaments were divided into two groups of 240 monofilaments each using a fiber-separating guide. Otherwise, two strip yarns were made using the same method and conditions as in Example 1. Using a reciprocating guide with 2 grooves, a groove width of 5.0 mm, and a groove spacing of 1.0 mm, the two strip yarns were wound onto a spool (paper tube) using the same method and conditions as in Example 1, thereby obtaining the yarn package of Example 9.

[0084] <Comparative Example 1>

[0085] Using the same materials as in Example 1, 120 monofilaments were directly spun into a fiber bundle without separation using a composite nozzle with 120 nozzle orifices. Otherwise, the core-sheath composite fiber was obtained using the same methods and conditions as in Example 1. This core-sheath composite fiber was stretched using the same methods and conditions as in Example 2 to obtain a multifilament yarn. Using a reciprocating guide with 1 groove and a groove width of 2.0 mm, the multifilament yarn was wound onto a spool (paper tube) using the same methods and conditions as in Example 1, thereby obtaining the yarn package of Comparative Example 1.

[0086] <Comparative Example 2>

[0087] Using a reciprocating guide with one groove and a groove width of 2.0 mm, two strip yarns made with the same materials, methods and conditions as in Example 1 are wound into one yarn. Otherwise, the two strip yarns are wound onto a spool (paper tube) with the same methods and conditions as in Example 1, thereby obtaining the yarn package of Comparative Example 2.

[0088] <Comparative Example 3>

[0089] To suppress bulging at both ends of the yarn layer, the contact pressure load applied to the spool (the force of the pressure roller pressing against the take-up spool) was set to 95.06 N, and the contact pressure level was set to 3.40 N / cm. Otherwise, the yarn package of Comparative Example 3 was obtained using the same materials, methods, and conditions as Comparative Example 2. In Comparative Example 3, the contact pressure level increased by 56% compared to Comparative Example 2.

[0090] <Comparative Example 4>

[0091] Using the same materials as in Example 1, the resin ejection rate of the hot melt composite spinning device relative to the core was set to 12.5 times that of Example 1 in the spinning process. The 480 monofilaments were divided into two groups of 240 monofilaments each using a fiber-separating guide. Otherwise, the core-sheath composite fiber was obtained using the same methods and conditions as in Example 1. The core-sheath composite fiber was stretched using the same methods and conditions as in Example 2 to obtain two (bundles) of multifilament yarns.

[0092] Using a reciprocating guide with 2 slots, a slot width of 5.0 mm, and a slot spacing of 1.0 mm, the two (bundles) of multifilament yarns are wound onto a bobbin (paper tube) in the same way and under the same conditions as in Example 1 above, thereby obtaining the yarn package of Comparative Example 4.

[0093] [evaluate]

[0094] Next, the yarn packages of Examples 1 to 9 and Comparative Examples 1 to 4, which were prepared by the aforementioned method, were evaluated according to the method shown below.

[0095] (a) Shape of the roll

[0096] For the yarn package of the embodiments and comparative examples, the winding outer diameter of the central portion and both ends, the step width when there are steps at both ends, the distance between adjacent yarns, the pitch, and the width of the yarn in the wound state were measured. Here, the winding outer diameter of the two ends refers to the outer diameter of the outermost part in the x-axis direction, and the winding outer diameter of the central portion refers to the nominal outer diameter of the yarn package excluding the two ends in the x-axis direction. Since this outer diameter represents the outer diameter near the central portion, it is defined as the winding outer diameter of the central portion.

[0097] (b) Physical properties of the yarn

[0098] For the yarn packages of the embodiments and comparative examples, the width and thickness of each yarn wound onto the spool were measured using a digital vernier caliper and a dial thickness gauge, respectively. Measurements were taken at the portion where the yarns were wound parallel to each other at the reciprocating section (end of axis x direction) with each yarn wound on the spool.

[0099] (c) Whether or not the collapse is entangled

[0100] By observing the appearance of the yarn package in the embodiments and comparative examples, a shape in which the winding side (end face of the yarn layer) is not perpendicular to the winding direction (axis x direction) of the bobbin but bulges out is defined as a "saddle shape," and a shape in which the winding end (end of the yarn layer in the axis x direction) is raised is defined as a "dumbbell shape." If either of these shapes is found, it is considered that there is "winding collapse." On the other hand, if neither the "saddle shape" nor the "dumbbell shape" is found, it is considered that there is "no winding collapse."

[0101] (d) Presence or absence of edge detachment

[0102] By observing the appearance of the yarn packages of the embodiments and comparative examples, if it is confirmed that the ribbon yarn or multifilament yarn has come off from the winding end of the bobbin (the end of the yarn layer in the x-direction) to the winding side with a length of more than 15 mm from the end, i.e., a short circuit, it is considered to have "side breakage". On the other hand, if no such short circuit is found, it is considered to have "no side breakage".

[0103] (e) Roll-out test

[0104] Figure 8 This is a schematic diagram illustrating the roll-out test method. When conducting the roll-out test, firstly, as... Figure 8As shown, the spool of the yarn package 10 of the embodiment and the comparative example is inserted into the rotating shaft 50, and the yarn is wound on the traction rollers 51a to 51c of the winding machine with a back tensioner in a longitudinally traction state. Furthermore, the tension is set to a back tension (extraction tension) of 0.075 g / dtex (=0.074 cN / dtex).

[0105] Subsequently, under longitudinal traction, the yarn is extracted at a speed of 120 m / min using a pull-out roller 52 such as a Nelson roller, and wound out of the yarn package. The result is evaluated as "no problem" when the yarn can be extracted to a length of more than 85% of the total winding length without any issues. If the yarn detaches from the end face and is cut during extraction, it is evaluated as "broken yarn".

[0106] The results above are summarized in Tables 1 and 2 below.

[0107] [Table 1]

[0108]

[0109] [Table 2]

[0110]

[0111] As shown in Table 2 above, the yarn packages of Comparative Examples 1 to 4, produced according to conventional methods, became "saddle-shaped" and "dumbbell-shaped," and "winding collapse" and "edge detachment" occurred. In contrast, as shown in Table 1 above, the yarn packages of Examples 1 to 9, produced within the scope of the present invention, have good shapes and excellent winding properties.

[0112] Specifically, regarding the yarn package of Example 1, the outer diameter of the central portion is 180 mm, the outer diameter of the two ends is 179 mm, the number of steps at both ends is one, and the step width is 3.2 mm. Furthermore, the distance between adjacent strip yarns is 2.1 mm, the pitch between adjacent strip yarns is 3.3 mm, and the width of the two strip yarns in the wound state is 4.5 mm. Moreover, the strip yarn wound in the yarn package of Example 1 has a fineness of 800 dtex, a width of 1.2 mm, and a thickness of 0.1 mm.

[0113] In the yarn package of Example 1, the yarns do not cross each other when wound on the spool, and the same applies in Examples 2 to 9 shown below. This is believed to be because even if there are two or more yarns wound on the spool, the multiple grooves provided on the reciprocating guide can restrict their movement, allowing the yarns to be wound approximately parallel. Furthermore, no "winding collapse" or "edge slippage" was observed with the yarn package of Example 1, and it was able to be pulled out without breakage over a length of 25 km during the unwinding test.

[0114] Regarding the yarn package of Example 2, the outer diameter of the central section is 180 mm, the outer diameter of the two ends is 179 mm, the number of steps at both ends is one, and the step width at both ends is 3.1 mm. Furthermore, the distance between adjacent yarns is 2.0 mm, the pitch between adjacent yarns is 3.0 mm, and the width of the two yarns in the wound state is 4.0 mm. Moreover, the multifilament yarn wound in the yarn package of Example 2 has a fineness of 800 dtex, a width of 1.0 mm, and a thickness of 0.1 mm. Furthermore, no "winding collapse" or "edge slippage" was observed with the yarn package of Example 2, and it was able to be pulled out without breakage over a length of 25 km in the unwinding test.

[0115] Regarding the yarn package of Example 3, the outer diameter of the central section is 180 mm, the outer diameter of the two ends is 179 mm, the number of steps at both ends is one, and the step width is 5.6 mm. Furthermore, the distance between adjacent strip yarns is 4.4 mm, the pitch of adjacent strip yarns is 9.2 mm, and the width of the two strip yarns in the wound state is 14 mm. Moreover, the strip yarn wound in the yarn package of Example 3 has a fineness of 3200 dtex, a width of 4.8 mm, and a thickness of 0.1 mm. Furthermore, no "winding collapse" or "edge detachment" was observed in the yarn package of Example 3, and it was able to be pulled out without breakage over a length of 6.3 km in the unwinding test.

[0116] Regarding the yarn package of Example 4, the outer diameter of the central portion is 180 mm, the outer diameter of the two ends is 179 mm, the number of steps at both ends is one, and the step width is 0.9 mm. Furthermore, the distance between adjacent strip yarns is 1.2 mm, the pitch of adjacent strip yarns is 1.5 mm, and the width of the two strip yarns in the wound state is 1.8 mm. Moreover, the strip yarn wound in the yarn package of Example 4 has a fineness of 200 dtex, a width of 0.3 mm, and a thickness of 0.1 mm. Furthermore, no "winding collapse" or "edge slippage" was observed in the yarn package of Example 4, and it was able to be pulled out without breakage over a length of 100 km in the unwinding test.

[0117] Regarding the yarn package of Example 5, the outer diameter of the central portion is 180 mm, the outer diameter of the two ends is 179 mm, the number of steps at both ends is one, and the step width at both ends is 7.3 mm. Furthermore, the distance between adjacent strip yarns is 5.7 mm, the pitch of adjacent strip yarns is 6.9 mm, and the width of the two strip yarns in the wound state is 8.1 mm. Moreover, the strip yarn wound in the yarn package of Example 5 has a fineness of 800 dtex, a width of 1.2 mm, and a thickness of 0.1 mm. Furthermore, no "winding collapse" or "edge slippage" was observed in the yarn package of Example 5, and it was able to be pulled out without breakage over a length of 25 km in the unwinding test.

[0118] Regarding the yarn package of Example 6, the outer diameter of the central portion is 180 mm, the outer diameter of the two ends is 179 mm, the number of steps at both ends is one, and the step width is 2.6 mm. Furthermore, the distance between adjacent strip yarns is 1.5 mm, the pitch of adjacent strip yarns is 2.7 mm, and the width of the two strip yarns in the wound state is 3.9 mm. Moreover, the strip yarn wound in the yarn package of Example 6 has a fineness of 800 dtex, a width of 1.2 mm, and a thickness of 0.1 mm. Furthermore, no "winding collapse" or "edge detachment" was observed in the yarn package of Example 6, and it was able to be pulled out without breakage over a length of 25 km in the unwinding test.

[0119] Regarding the yarn package of Example 7, the outer diameter of the central portion is 180 mm, the outer diameter of the two ends is 179 mm, the number of steps at both ends is two, the step width of the inner step is 3.2 mm, and the step width of the outer step is 3.1 mm. Furthermore, the distance between adjacent strip yarns is 2.1 mm, the pitch of adjacent strip yarns is 3.3 mm, and the width of the three strip yarns in the wound state is 7.8 mm.

[0120] Furthermore, the strip yarn wound in the yarn package of Example 7 has a fineness of 800 dtex, a width of 1.2 mm, and a thickness of 0.1 mm. Moreover, no "winding collapse" or "edge detachment" was found in the yarn package of Example 7, and it was able to be pulled out without breakage within a length of 16 km in the unwinding test.

[0121] Regarding the yarn package of Example 8, the outer diameter of the central portion is 180 mm, the outer diameter of the two ends is 179 mm, and the number of steps at both ends is 4: the first step from the inside to the outside is 3.2 mm, the second step is 3.1 mm, the third step is 3.1 mm, and the fourth step is 3.0 mm. Furthermore, the distance between adjacent ribbon yarns is 2.1 mm, the pitch of adjacent ribbon yarns is 3.3 mm, and the width of the 5 ribbon yarns in the wound state is 14.4 mm.

[0122] Furthermore, the strip yarn wound in the yarn package of Example 8 has a fineness of 800 dtex, a width of 1.2 mm, and a thickness of 0.1 mm. Moreover, no "winding collapse" or "edge detachment" was found in the yarn package of Example 8, and it was able to be pulled out without breakage within a length of 10 km in the unwinding test.

[0123] Furthermore, the strip yarn wound in the yarn package of Example 8 is split into 5 strands in the wound state. As can be seen during use, the total width of the 5 strands during the pull-out test is approximately 14mm to 15mm. When winding with a width greater than 15mm, if the yarn is combined during pull-out for use as a single strand, the tension of the strip yarn or multifilament yarn at the left and right ends tends to fluctuate relative to the tension of the strip yarn or multifilament yarn near the center. In particular, the tension fluctuation is greater when passing through the reversing section at both ends in the x-axis direction, thus easily leading to slack. Therefore, it is preferable to set the total width of the multiple yarn strands to 15mm or less when winding.

[0124] Regarding the yarn package of Example 9, the outer diameter of the central portion is 180 mm, the outer diameter of the two ends is 179 mm, the number of steps at both ends is one, and the step width is 5.6 mm. Furthermore, the distance between adjacent yarns is 4.4 mm, the pitch between adjacent yarns is 9.2 mm, and the width of the two yarns in the wound state is 14 mm. Moreover, the multifilament yarn wound in the yarn package of Example 9 has a fineness of 6400 dtex, a width of 4.8 mm, and a thickness of 0.2 mm. Furthermore, no "winding collapse" or "edge slippage" was observed in the yarn package of Example 9, and it was able to be pulled out without breakage over a length of 3.1 km in the unwinding test.

[0125] In contrast, the yarn package of Comparative Example 1, which is formed by repeatedly winding a single yarn using conventional methods, has the following winding shape (dumbbell shape): the outer diameter of the winding at the center is 180 mm, the outer diameter of the winding at both ends is 190 mm, and the two ends bulge with a width of about 10 mm, indicating a collapsed winding state. The multifilament yarn wound in the yarn package of Comparative Example 1 has a fineness of 1600 dtex, a width of 1.0 mm, and a thickness of 0.2 mm.

[0126] The yarn package of Comparative Example 1 was formed by winding a bundle of multifilament yarn with a fineness of 1600 dtex. On the other hand, the yarn package of Example 2, which was formed by winding two bundles of multifilament yarn with a fineness of 800 dtex, had a total fineness of 1600 dtex, the same as the yarn package of Comparative Example 1, but it did not experience winding collapse. Thus, the shape with raised ends in the yarn package of Comparative Example 1, compared to the case of winding the yarn into two or more strands as in Example 2, is believed to be caused by the following reasons.

[0127] That is, near the center of the take-up spool, the yarn is wound in a manner that always crosses with the take-up bundle of the next layer. However, when it turns back and forth in the opposite direction at both ends, although for a short time, the yarn temporarily passes through a state of being wound parallel to the rotation direction of the spool (parallel winding section) and then begins to cross in the opposite direction. Therefore, as the parallel winding sections accumulate and stack at both ends of the yarn layer, the roll diameter increases, resulting in a shape that is raised compared to the area near the center.

[0128] On the other hand, regarding the yarn package of Example 2, the total fineness is 1600 dtex, but since it is separated into two, only one bundle is necessarily wound back and forth in parallel at both ends of the yarn layer. Therefore, no bulging at both ends occurs in the yarn package of Example 2. When two yarns are split into fibers of the same fineness (1 / 2 split), or when multiple fiber bundles are split into multiple fiber bundles of the same fineness and wound, the layer thickness is smaller (the outer diameter of the winding is smaller) closer to the two ends, resulting in steps at both ends of the yarn layer.

[0129] Regarding the number of steps, there is one level when there are two fibers and two levels when there are three fibers, with the number of levels increasing correspondingly to the number of fibers. Since the winding is performed based on this principle, it is believed that the ends of the yarn layer in this embodiment tend to have a lower fiber density compared to the area near the center. It is assumed that the same applies when winding ribbon yarn.

[0130] Furthermore, in the unwinding test, for the yarn package of Comparative Example 1, the yarn wound on the dumbbell-shaped ridge detached from the winding end, and the yarn became tangled together. Breakage occurred after only 800m (approximately 3% of the total winding length) had been pulled out. Thus, compared to the yarn packages of Examples 1 to 9 described above, the unwinding characteristics of the yarn package of Comparative Example 1 were poor.

[0131] Furthermore, the yarn package of Comparative Example 2, which is formed by winding two yarn strips together, has the following winding shape (dumbbell shape): the outer diameter of the winding at the center is 180 mm, the outer diameter of the winding at both ends is 185 mm, and the two ends bulge with a width of about 10 mm, indicating a collapsed winding state. This is because, since two strip yarns are wound together as one, the two strips overlap and are wound at both ends of the reciprocating yarn layers.

[0132] Regarding the ribbon yarn wound in the yarn package of Comparative Example 2, the fineness is 800 dtex, the width is 1.2 mm, and the thickness is 0.1 mm. Furthermore, in the unwinding test, the ribbon yarn wound on the dumbbell-shaped raised portion of the yarn package of Comparative Example 2 detached from the winding end, resulting in the yarn becoming entangled. Breakage occurred after only 600 m (approximately 2% of the total winding length) was pulled out. Thus, the yarn package of Comparative Example 2 also exhibits poorer unwinding characteristics compared to the aforementioned Examples 1 to 9.

[0133] Regarding the yarn package of Comparative Example 3, which was wound by increasing the contact pressure load generated by the pressure roller compared to Comparative Example 2, the outer diameter of the winding at the center was 180 mm, and the outer diameter of the winding at both ends was 180 mm. No bulging occurred at the ends, and it did not form a dumbbell shape. However, the yarn package of Comparative Example 3 formed a so-called "saddle shape" with bulging ends, indicating a state of winding collapse, and "edge slippage" was also observed. In the yarn package of Comparative Example 3, the lower layer of strip yarn located on the sides of both ends in the x-axis direction was pushed outwards from the winding ends and wound due to the increased contact pressure generated by the pressure roller, thus causing the bulging state, and edge slippage was also considered to be due to this reason.

[0134] Regarding the strip yarn wound in the yarn package of Comparative Example 3, the fineness is 800 dtex, the width is 1.2 mm, and the thickness is 0.1 mm. Furthermore, at the very end of the strip where the winding direction reverses, traces of compression and fuzzing were found, confirming that the yarn was damaged. Moreover, in the unwinding test, for the yarn package of Comparative Example 3, at the edge-breaking point, the strip yarn detached from the winding end, and due to fuzzing, the yarn became tangled, resulting in breakage after only 800 m (approximately 3% of the total winding length) was pulled out. Thus, the yarn package of Comparative Example 3 is less practical for use compared to the aforementioned Examples 1 to 9.

[0135] Regarding the yarn package of Comparative Example 4, which uses a reciprocating guide with two grooves to wind two bundles of 10000 dtex multifilament yarn, the outer diameter of the winding at the center is 180 mm, and the outer diameter of the winding at both ends is 179 mm. There are no bulges at the ends of the yarn layers, but rather steps are formed. The number of steps formed at the ends of the yarn layers in the yarn package of Comparative Example 4 is one, and the width is 10 mm. Furthermore, the distance between adjacent yarns is 1.8 mm, the pitch between adjacent yarns is 7.1 mm, and the width of the two yarns in the wound state is 12.4 mm.

[0136] However, in the yarn package of Comparative Example 4, due to the relatively high fineness of the wound multifilament yarn, a portion of the yarn at both ends of the package broke off, resulting in a collapsed package and edge stripping. The multifilament yarn wound in the yarn package of Comparative Example 4 had a fineness of 10000 dtex, a width of 5.3 mm, and a thickness of 0.32 mm. Furthermore, in the unwinding test, in the yarn package of Comparative Example 4, a portion of the stripped yarn's individual fibers became entangled, resulting in breakage and making it unusable.

[0137] Based on the above results, it is confirmed that a yarn package that does not bulge at both ends and is not prone to collapse or edge detachment during winding can be obtained according to the present invention.

[0138] Explanation of reference numerals in the attached figures

[0139] 1, 10, 11, 12, Yarn package; 2, Bollard; 3, 13, Yarn layer; 3a, 13a, Step; 4, Pressure roller; 5, Reciprocating guide; 5a, 5b, Groove; 31a, 31b, Yarn strip; 32a, 32b, 32c, Composite fiber (single fiber); 33, First resin component (low melting point component); 34, Second resin component (high melting point component); 50, Rotating shaft; 51a-51c, Roller; 52, Extraction roller.

Claims

1. A yarn package, wherein the yarn is wound at an angle with the inclination angle reversed at each layer, by interlacing the yarn of the nth layer with the yarn of the (n+1)th layer, where n is a natural number, and wherein... The yarn package has the following features: A cylindrical spool that lacks a flange; and A yarn layer is formed by winding m multifilament yarns or ribbon yarns at intervals on a cylindrical bobbin in a reciprocating, inclined manner, where m is a natural number greater than 2. The m multifilament yarns constituting the yarn layer are formed by twisting together dozens to hundreds of composite fibers, which are produced by melt spinning two thermoplastic resins with different melting points using a composite nozzle, into a single yarn, or by mixing single fibers formed from a single resin with dozens to hundreds of the aforementioned composite fibers and twisting them together to form a single yarn. The m ribbon-like yarns constituting the yarn layer are formed by integrating dozens to hundreds of the composite fibers into one yarn, or by mixing the single fiber with dozens to hundreds of the composite fibers to integrate and form one yarn. The m multifilament yarns and the m ribbon yarns each have a combined fineness of 100 dtex to 6400 dtex. The m multifilament yarns wound on the cylindrical spool and the m ribbon yarns have the same reciprocating width but different reverse rotation positions. In the yarn layer, the diameters of the two ends are smaller than the diameter of the central portion in the axial direction, and m-1 steps are formed at both ends in the axial direction. The total width of the m multifilament yarns or m ribbon yarns in the wound state is less than 15 mm. This total width is the sum of the width of the corresponding m yarns and the gaps between the yarns. The m multifilament yarns or the m strip yarns are simultaneously wound out from the yarn layer.

2. The yarn package according to claim 1, wherein, In the yarn layer, the number of yarns wound at both ends in the axial direction is less, and the yarn density is lower than the number and yarn density of yarns wound in the central part in the axial direction. The m multifilament yarns or m ribbon yarns constituting the yarn layer are wound approximately parallel to each other within the same layer, intersecting only with the yarns of the upper and lower layers.

3. A method for manufacturing a yarn package, wherein the yarn of the nth layer is wound at an angle with the inclination angle reversed for each layer, thereby manufacturing the yarn package. Here, n is a natural number. The manufacturing method includes a winding process in which m multifilament yarns, each with a total fineness of 100 dtex to 6400 dtex, or each strip yarn with a total fineness of 100 dtex to 6400 dtex, are wound at intervals and in a reciprocating, inclined manner onto a flangeless bobbin, where m is a natural number greater than 2. The m multifilament yarns are formed by twisting together dozens to hundreds of composite fibers, which are produced by melt spinning two thermoplastic resins with different melting points, to make one yarn, or by mixing single fibers formed from a single resin with dozens to hundreds of the aforementioned composite fibers and twisting them together to make one yarn. The m ribbon-like yarns are formed by integrating dozens to hundreds of the aforementioned composite fibers into a single yarn, or by mixing the single fiber with dozens to hundreds of the aforementioned composite fibers to form a single yarn. In the winding process, for the m multifilament yarns or the m ribbon yarns, the reciprocating width is the same for all yarns, while the reversing position changes according to each yarn. Therefore, the diameter of the yarn layer formed on the bobbin is set to be smaller at both ends compared to the center in the axial direction, and m-1 steps are formed at both ends of the yarn layer in the axial direction. Furthermore, in the wound state, the total width of the m multifilament yarns or the m ribbon yarns is less than 15 mm, where the total width is the sum of the width of the corresponding m yarns and the gaps between the yarns. A yarn package is formed from which the m multifilament yarns or the m strip yarns are simultaneously wound out from the yarn layer.

4. The method for manufacturing a yarn package according to claim 3, wherein, In the winding process, the number of yarns wound at both ends in the axial direction is less than the number of yarns wound in the central part in the axial direction, the yarn density at both ends is lower than the yarn density at the central part, and the m multifilament yarns or m ribbon yarns constituting the yarn layer are wound approximately parallel to each other in the same layer, only intersecting with the yarns of the upper and lower layers.

5. The method for manufacturing a yarn package according to claim 3 or 4, wherein, A reciprocating guide with more than m grooves is used to simultaneously wind the m multifilament yarns or the m strip yarns.

6. The method for manufacturing a yarn package according to claim 5, wherein, The spacing between the slots of the reciprocating guide is 0.3mm to 5mm.

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