JP6728936B2 - Bulky structure yarn - Google Patents

Description

The present invention relates to a bulky structure yarn in which a large number of large loops are formed in a surface layer portion made of synthetic fiber. The bulky structured yarn of the present invention is extremely bulky because the sheath yarn has a large loop shape in the surface layer, and the presence of the mutually bulky structured yarns with an excluded volume provides a soft texture. Further, although the large loop has an appropriate rigidity, the yarn itself is a very lightweight fiber, so that the yarn has an excellent bulky structure that is extremely lightweight and retains heat. Furthermore, since the sheath yarn has a three-dimensional crimp, the entanglement between the bulky structure yarns is suppressed, and the handleability in the molding process is good, and it is used in a wide range of fields from clothing applications to industrial capital applications. Can be applied.

Synthetic fibers made of thermoplastic polymers such as polyester and polyamide are characterized by high basic properties such as mechanical properties and dimensional stability, and excellent balance. For this reason, the fiber materials that utilize them are not only used for clothing, but also for interiors, vehicle interiors, industrial applications, etc., in addition to developing basic performance by spinning due to polymer properties, and by adopting various structural forms by high-order processing. It's being used. It is no exaggeration to say that technological innovations have been made with the imitation of natural materials as the motivation for the development of new technologies related to synthetic fibers, and various technologies have been developed to allow synthetic fibers to exhibit functions derived from natural complex structural forms. Proposals have been made. For example, there are various things such as structural coloring represented by morpho butterflies and water repellency seen in lotus leaves due to the appearance of peculiar texture (chime, flexibility) by imitating the cross section of silk. One of them is efforts to realize functions such as soft texture, light weight and heat retention by natural feathers.

Natural feathers are used by mixing down balls (grain cotton shape) and feathers (feather shape), which are generally collected in small amounts from the chest of waterfowl. These are derived from the specific structural form of the keratin fibers, are rich in soft texture, easily follow the body, and exhibit excellent light weight and heat retention. Therefore, even a general user recognizes the function of products using natural feathers as stuffed cotton, and is widely applied to clothing such as bedding and jackets. However, from the viewpoint of nature conservation, there are restrictions on the capture of water birds, and there is a restriction on the total production of natural feathers. Furthermore, due to the recent abnormal weather and the occurrence of epidemics, the supply amount has changed greatly, and in addition to the soaring prices, the unstable supply amount is becoming a problem. In addition, the use of natural feathers often causes problems such as peculiar odor and animal allergies despite many steps such as hair collection, selection, disinfection, degreasing, etc. There are also moves to eliminate the use of feathers. Therefore, attention is focused on batting materials made of synthetic fibers that can be stably supplied.

Although many batting materials made of synthetic fibers have been proposed for a long time, there have been no examples of reaching natural feathers in terms of basic characteristics such as bulkiness, compression recovery, and soft texture.
For example, Patent Documents 1 and 2 disclose a method of modifying a frictional property of fibers by attaching a silicone-based oil agent to ordinary fibers. Certainly, the use of silicone oils may give the fibers a slimy feel and slightly improve the texture. However, since the fibrous structure itself is poor in bulkiness and compression recovery in the first place, it does not reach that of natural feathers.
Further, as shown in Patent Document 3 and Patent Document 4, by making the fiber aggregate state spherical or radial, the bulkiness due to the structure is improved. However, it feels a foreign substance when compressed, and is not as good as the soft texture of natural feathers.

In the fibrous structure mainly composed of these short fibers, the bulkiness and flexibility (compression recovery) of the structure are due to the mechanical properties and fineness (thickness) used. For this reason, further improvement is required in order to achieve both properties such as natural feathers where bulkiness and flexibility are contradictory.

The yarn processing technology that has been conventionally used for the purpose of increasing the added value of fibers is, for example, actual twisting of fibers followed by untwisting, or mixing of one or more types of fibers with a fluid processing nozzle or the like. It is generally known that a textured yarn having bulkiness can be produced by doing so. Since the processed yarn having such bulkiness is basically a long fiber, it can be processed into various forms, and it can be applied to batting material by taking advantage of the bulkiness and soft texture of the processed yarn. Conceivable.

In Patent Document 5, two types of fibers are used, and one fiber is fed to a waist gauge while imparting yarn wobbling, etc., and the actual twist is collectively applied to the surface layer by the fibers to which yarn wobbling is imparted. Form a loop. After that, a technique of obtaining a bulky processed yarn by further twisting by rubbing with two disks or the like to obtain a bulky processed yarn is disclosed. Certainly, in this technique, there is a possibility that a bulky structure yarn having a loop made of a sheath yarn can be obtained by adjusting the degree of yarn fluctuation and the like according to the conventional method. Furthermore, there is a possibility that it can be applied as a batting material by premixing the binder and then fusing it after processing to fix the loop. However, when the actual twist is applied to the loop yarn in which the sheath yarn partially protrudes and the yarn is opened by rubbing with a rubber or the like in a mechanical rubbing machine, the protruding loop is partially broken or deteriorated. Will be things. When the processed yarn is used as batting, it is necessary to bundle several yarns to dozens of yarns in the end, so that the sheath yarn may be partially broken or deteriorated (fluff). Entangling with the sheath yarn of other processed yarn may deteriorate unwinding in the forming process or deteriorate processability. Furthermore, the bulkiness may be deteriorated over time due to the feeling of foreign matter when the sheath yarn in which a part is remarkably entangled is filled to impair the texture, or to promote the entanglement. Patent Document 5 is characterized in that heat treatment is applied after the untwisting step, or the sheath yarns are fused with a binder in order to firmly fix the sheath yarns. For this reason, there is also a problem in that the entangled portions are fusion-bonded and fixed, so that the feeling of foreign matter becomes remarkable.

Patent Document 6 is a technique in which compressed air is jetted from a direction perpendicular to a running yarn in an entanglement nozzle to open and entangle the yarn, so that an excessively supplied sheath yarn is fixed with a yarn length difference. In Patent Document 6, as in Patent Document 5, there is a possibility that a textured yarn having a bulkiness in which a sheath yarn having a loop shape is present in the surface layer can be obtained. However, as in Patent Document 6, when the traveling yarns in the nozzle are disturbed, and the fibers are opened and entangled, the yarns sway in a very short cycle to cause entanglement of the traveling yarns. Become. Therefore, small loops that are naturally affected by the nozzle shape are excessively formed at high frequency. In addition, the size of the loop fluctuates in the fiber axis direction due to the entanglement of the sheath yarn with the core yarn at random, and the bulkiness is restricted. Further, the loop yarn formed in the nozzle is discharged inside the nozzle by the jet air after being retained inside the nozzle. Therefore, the size of the loop and the length of the sheath yarn forming the loop vary in the fiber axis direction of the processed yarn to form slack. In this case, the slackened sheath yarn is particularly liable to be entangled with the other sheath yarn, and there still remains a problem that the process passability in higher-order processing and the entangled portion of the sheath yarn lead to a feeling of foreign matter.

The entanglement of bulky processed yarns having such slack is generally recognized as a fastener phenomenon, and affects unwinding in higher-order processing, deterioration of the texture of textile products, and durability. It is supposed to be. For this reason, there are efforts to try to improve the fluid-processed yarn as a main component.
Therefore, there is a demand for a bulky structured yarn in which the entanglement between the processed yarns is suppressed while having a very high bulkiness due to the large loop.

Japanese Examined Patent Publication No. 52-28426 (claims) JP-B-52-50308 (Claims) JP-B-48-7955 (claims) Japanese Patent Publication No. 51-39134 (Claims) JP, 2011-246850, A (claim) JP 2012-67430 A (Claims)

INDUSTRIAL APPLICABILITY The present invention is a bulky structured yarn made of synthetic fiber, in which entanglement between bulky structured yarns is suppressed even though the surface layer has a large loop shape, and handleability in high-order processing is good, It is to provide bulky structured yarns that are not only soft to the touch but also lightweight and retain heat.

The above object can be achieved by the following means.

(1) In a bulky structured yarn composed of a core yarn that substantially fixes the sheath yarn by intersecting the sheath yarn forming the loop and the sheath yarn, a continuous loop is formed without breaking the sheath yarn. The bulky structured yarn is characterized in that the size of the loop is 1.0 mm to 100.0 mm and the sheath yarn is a composite fiber having a density of less than 1.00 g/cm ³ .

(2) The bulky structured yarn according to (1), wherein the sheath yarn has a three-dimensional crimp.

(3) The bulky structured yarn according to (1) or (2), wherein the sheath yarn is a sea-island composite fiber having a hollow cross section with a hollow ratio of 10% or more.

(4) The bulky structure according to any one of (1) to (3), wherein the core yarn is a sea-island composite fiber having a hollow cross section with a hollow ratio of 10% or more, and has a three-dimensional crimp. yarn.

(5) The bulky structured yarn according to (3) or (4), wherein the island component of the sea-island composite fiber is polyolefin and the sea component is polyester.
(6) A fiber product containing at least a part of the bulky structured yarn according to any one of (1) to (5).

The bulky structure yarn of the present invention has a large loop shape on the surface layer, but entanglement between the bulky structure yarns is suppressed, and the handleability in high-order processing is good, but the soft texture In addition, it is lightweight and has excellent heat retention.

Schematic side view of an example of the bulky structured yarn of the present invention Simulated drawing to explain the yarn surface measurement method Simulated diagram for explaining three-dimensional crimp structure The figure which shows typically an example of the cross section of the hollow sea-island composite yarn which comprises the bulky structure yarn of this invention. Schematic process chart schematically showing an example of the method for producing the bulky structured yarn of the present invention Schematic side view for explaining a suction nozzle used in the method for producing a bulky structured yarn of the present invention Schematic cross-sectional view for explaining the discharge holes of the spinneret for hollow cross-sections used in the method for producing a bulky structure yarn

Hereinafter, the present invention will be described in detail together with preferred embodiments.
The bulky structured yarn of the present invention is composed of a sheath yarn that forms a loop and a core yarn that substantially fixes the sheath yarn by intersecting the sheath yarn. Further, the present invention is characterized in that it is a conjugate fiber which forms a continuous loop without breaking the sheath yarn and has a density of less than 1.00 g/cm ³ .

Synthetic fibers are used for the sheath yarn and the core yarn constituting the bulky structured yarn of the present invention. The synthetic fiber referred to here is a fiber made of a high-molecular polymer. As the synthetic fiber, a fiber produced by melt spinning or solution spinning can be adopted. Among the high molecular weight polymers, thermoplastic polymers that can be melt-molded are suitable for use in the present invention because the fibers used in the present invention can be produced by employing the melt spinning method with high productivity.

The thermoplastic polymer referred to here is, for example, polyethylene terephthalate or its copolymer, polyethylene naphthalate, polybutylene terephthalate, polytrimethylene terephthalate, polypropylene, polyolefin, polycarbonate, polyacrylate, polyamide, polylactic acid, thermoplastic polyurethane, etc. Melt-moldable polymers of Among these thermoplastic polymers, polycondensation polymers typified by polyesters and polyamides are crystalline polymers and have a high melting point, so they were heated at a relatively high temperature during the subsequent steps, molding and actual use. Even in the case, there is no deterioration or settling, which is preferable. From the viewpoint of heat resistance, it is preferable and preferable that the melting point of the polymer is 165° C. or higher.

To the polymer used in the present invention, various additives such as inorganic materials such as titanium oxide, silica, barium oxide, carbon black, colorants such as dyes and pigments, flame retardants, optical brighteners, antioxidants, or ultraviolet absorbers are added. The agent may be included in the polymer.

In particular, when polyolefin is selected, it is preferable from the viewpoint of improving the lightness which is an object of the present invention, and among them, polypropylene having a low density is more preferable. Further, in order to have not only light weight but also resistance to settling against compression and the like, from the viewpoint of giving the synthetic fibers constituting the bulky structured yarn sufficient strength, it is preferable that the polypropylene used has a high molecular weight. It is preferable that the melt flow rate (MFR), which is an index of, is 20 g/10 min or less. The MFR referred to here is the amount of resin extruded per 10 minutes measured according to the method described in JIS K 7210:1999, and generally, the higher the molecular weight of the resin, the smaller the MFR tends to be. If the MFR of the polypropylene used is within the above range, the bulky structured yarn will not easily get settled against compression or bending during use, and it will withstand impacts during processing. There will be no problems. Further, when polypropylene is used for the bulky structured yarn of the present invention, there is a risk of causing exothermic heat of oxidation during use in clothing products and the like, and in order to avoid such adverse effects, the polypropylene to be used contains an antioxidant in order to prevent oxidation. It is preferably contained.

As illustrated in FIG. 1, the bulky structure yarn of the present invention includes a sheath yarn (1 in FIG. 1) forming a loop and a core yarn (FIG. 1) that substantially fixes the sheath yarn by intersecting with the sheath yarn. 2).

The core yarn referred to here means a filament existing 0.6 mm or less from the yarn surface (3 in FIG. 2). The yarn surface means a straight line connecting the yarn guides 4 when the processed yarn is threaded between the pair of yarn guides (4 in FIG. 2). The filament existing at a distance (5 in FIG. 2) from the yarn surface of 0.6 mm or less serves as the core yarn in the present invention, and serves as the base point of the large loop. Further, the filament protruding in a loop shape at a distance of 1.0 mm or more from the yarn surface is the sheath yarn referred to in the present invention, and controls the bulkiness of the bulky structured yarn of the present invention. The present invention is characterized by comprising a core yarn that substantially fixes a sheath yarn that forms a large loop. The term "substantially fixing" here means that the sheath yarn intersects with the core yarn. And means being independent. The self-supporting state is that the sheath yarn stands in the outer layer direction of the bulky structure yarn to form a loop, starting from the intersection of the core yarn and the sheath yarn. In addition, in many cases, the filaments are actually mixed at the point where the filaments intersect with each other, that is, near the starting point of the loop. For this reason, the point where the sheath yarn forming the apex of the loop at 1.0 mm or more from the yarn surface intersects with the straight line located at 0.6 mm from the yarn surface is defined as an intersection point.

The crossing point has a role of supporting the independence of the loop made of the sheath yarn, which is a feature of the present invention, and it is preferable that the crossing point exists in a certain period. From this viewpoint, it is preferable that the core yarn and the sheath yarn in the bulky structure yarn have 1 to 30 crossing points/mm. Within such a range, even if the sheath yarn has a three-dimensional crimp, loops will be present at appropriate intervals, which is preferable. From this viewpoint, it is more preferable that the number of intersections is 5 to 15/mm.

A photoelectric fluff detection device can be used to determine the core yarn and the sheath yarn and to continuously evaluate the number of loops per unit length in the fiber axis direction of the processed yarn. For example, it is good to evaluate 0.6 mm and 1.0 mm from the yarn surface under the conditions of a yarn speed of 10 m/min and a running yarn tension of 0.1 cN/dtex, using a photoelectric fuzz counter (TORAY FRAY COUNTER).

The sheath yarn having the large loop of the present invention is substantially fixed by the core yarn and has a form protruding in the outer layer direction in the cross section of the processed yarn.
The protrusion of the large loop referred to here corresponds to the distance from the yarn surface (5 in FIG. 2), and the processed yarn in which a fixed length of yarn is hooked on the pair of yarn guides is two-dimensionally observed from the side, and this observation It is measured from the image taken. 10 randomly selected threads are photographed so that the entire loop can be observed, and 10 protrusions of the loop are photographed in each image. This operation is performed on a total of 10 images, and 100 points in total are measured in millimeters up to the second decimal point. The average value of these numerical values was calculated, and the value rounded off to the second decimal place was used as the loop size in the present invention.

According to the study of the present inventors, it is preferable that the large loop protrudes from the yarn surface in a range of 1.0 mm or more and 100.0 mm or less, and in such a range, the sheath yarns are less likely to be entangled with each other, and the present invention The desired bulkiness and the effect of suppressing entanglement can be exhibited without any problem. Further, in consideration of the processability of the bulky structure yarn described later, 3.0 mm or more and 70.0 mm or less are more preferable. Further, considering that repeated compression recovery deformation is added under a harsh environment such as sports clothing, it is particularly preferable that the thickness is 5.0 mm or more and 60.0 mm or less.

Further, in the study by the present inventors, it was found that the above-mentioned effect tends to be reduced when the large loop made of the sheath yarn is broken in the middle or partially deteriorated. Therefore, in the present invention, which aims to achieve the contradictory properties of suppressing bulkiness and entanglement, which are not available in the past, the sheath yarn may form a continuous loop without being broken in the middle of the loop. is important.

In the determination of this breakage, it can be confirmed by observing at 10 positions randomly selected from the processed yarn, at a magnification that can confirm the next intersection point (entire loop) from the intersection point of the core yarn and the sheath yarn. it can. At 10 points to be observed, 10 pieces of sheath yarns were observed, respectively, and it was found that the average number of broken portions of 100 pieces was 0.2 or less without the sheath yarn of the present invention being partially broken. , Means that they are in a continuous loop. Within such a range, there is substantially no sheath yarn having a free yarn end, and the sheath yarn can exist without being entangled with other sheath yarns. When adding a conventional twisting process after adding the actual twisting, or when disturbing and opening the fiber in the nozzle with a strong air jet, the running yarn is struck by the high frequency inside the nozzle made of metal, causing breakage and deterioration. There is a case. Furthermore, when a large loop like that of the present invention is to be formed, it is necessary to rub between the rubber discs or the like to untwist, so that the sheath yarn is broken or greatly deteriorated. Therefore, it is considered that the broken sheath yarn is wound around another sheath yarn or is entangled with each other to promote the fastener effect, which results in a restriction on the structural form of the processed yarn and the higher-order processing. In the present invention, this point is greatly improved, and the effect of weaving the sheath yarn forming the loop can be sufficiently exerted.

The bulky structured yarn of the present invention needs to be a conjugate fiber having a sheath yarn density of less than 1.00 g/cm ³ . The term "sheath yarn density" as used herein means the weight per unit volume of the sheath yarn, and is measured by a method according to JIS L 1013:2010 using a density gradient tube. When the density of the sheath yarn is within the above range, when it is used as a stuffed cotton for clothes, bedding and the like, the product is highly lightweight and has high comfort during use. From the viewpoint of enhancing the lightness of the bulky structured yarn, the density of the sheath yarn is preferably 0.95 g/cm ³ or less, and more preferably 0.90 g/cm ³ or less. In order to reduce the density of the sheath yarn, for example, a method of using a low-density polymer or a method of forming a hollow cross section as described later can be mentioned, but considering the range in which the fiber form can be retained, the sheath yarn of the present invention The lower limit of the density is substantially 0.70 g/cm ³ .

In addition, the composite fiber referred to here is a synthetic fiber composed of two or more different polymers, and depending on the combination of different polymers used, various properties which cannot be obtained by the synthetic fiber composed of a single polymer are imparted. It is possible. The combination of polymers used for this conjugate fiber can be appropriately selected from the above-mentioned polymer group, for example.

In the bulky structured yarn of the present invention, the shape of the loop made of the sheath yarn is that protruding from the core yarn to the outer layer starting from the intersection point, and the shape thereof is more than that of the arch loop formed by general entanglement. It is preferable that the shape is a krunodal loop (tear drop shape). In the case of the arch type loop, the intersection point of the core yarn and the sheath yarn is not fixed, and the loop has a feature of moving with a degree of freedom, but when compressive deformation is applied to the bulky structure yarn, The intersection will move. For this reason, it is difficult to return to the original shape after compression deformation, which may be disadvantageous in terms of bulkiness and durability. On the other hand, in the case of the krunodal type loop, the loop is almost fixed at the intersection with the core thread, so that the loop of the sheath thread easily returns to its original shape even after compression deformation, and in the first place it has repulsion. The shape is suitable for exhibiting bulkiness. Generally, the formation of the krunodal type loop has been a disadvantageous shape from the viewpoint of suppressing the entanglement of the sheath yarns, which is the object of the present invention. From the viewpoint of suppressing the entanglement of the sheath yarns due to such a loop shape, the sheath yarn preferably has a three-dimensional crimp. Since the inventors of the present invention have reached a bulky structure yarn that has never existed in the past, as a result of diligent studies toward the use of a krunodal type loop, the use of the three-dimensional crimped yarn as the sheath yarn of the present invention has been a conventional problem. It has been found that the entanglement of the sheath yarn can be suppressed and a dramatic increase in bulkiness can be realized by the synergistic effect with the loop shape.

The three-dimensional crimped structure in the present invention means that a filament single yarn as illustrated in FIG. 3 has a spiral structure. In this three-dimensional crimp evaluation, 10 or more single yarns are sampled at each of 10 locations randomly selected from the processed yarn, and the crimped form of each single yarn can be confirmed by a digital microscope or the like. It can be evaluated by observing at a magnification. In this image, when the observed single yarn has a spirally wound form, it is determined to have a three-dimensional crimp structure, and when it has a straight form, the crimp is formed. It is determined that it does not have a structure.

In order to make the present invention more effective, the size of the three-dimensional crimp is in the micron order expressed by the latent crimped yarn collected by a general production method such as the conventional side-by-side composite fiber or hollow fiber. It is preferable that it is on the order of millimeters (10 ⁻³ m) rather than (10 ⁻⁶ m). In the present invention, the bulkiness and rebound of the processed yarn in the circumferential direction and the cross-sectional direction can be freely controlled by the size of the three-dimensional crimp. It is also possible to suppress the entanglement of the sheath yarns, which is one of the objects of the invention. In particular, by setting the crimp size to the millimeter order, it is excellent mainly from the viewpoint of achieving both bulkiness and compressibility of the sheath yarn, and in addition, suppressing the entanglement of the sheath yarn.

In the bulky structured yarn of the present invention, the cross-sectional shape of the conjugate fiber used as the sheath yarn is not particularly limited, but it is preferably a sea-island conjugate fiber having a hollow cross section with a hollow ratio of 10% or more. The sea-island conjugate fiber here is a conjugate fiber having a cross-sectional structure in which island components made of a polymer are scattered in sea components made of the other polymer. The fact that the sheath yarn has a hollow cross section is an advantage of the manufacturing method described later, in addition to the fact that the size of the three-dimensional crimp can be controlled relatively freely from a large size to a small size, and in addition to being a large loop self-supporting It is suitable from the viewpoint. That is, in the bulky structured yarn of the present invention, the large loop made of the sheath yarn is responsible for bulkiness. The self-sustaining of the sheath yarn starts from an intersection with the core yarn and enables the self-sustaining by the rigidity of the sheath yarn. However, considering the resistance to set and the like, the weight of the sheath yarn itself is preferably light. Therefore, specifically, it is preferable that the sheath yarn has a lower density (weight per unit volume), and fibers having a hollow cross section are preferably used. From the viewpoint of the lightness of the sheath yarn, it is more preferable to have a hollow cross section with a hollow ratio of 20% or more. The term “hollowness” as used herein means that a fiber having a hollow cross section is cut, and then the cut surface is two-dimensionally photographed at a magnification at which 10 or more fibers can be observed with an electron microscope (SEM). Ten randomly selected fibers are extracted from the photographed image, and the areas of the fibers and hollow portions are measured using image processing software to obtain the area ratio. The above values were measured for each of the 10 images, and the average value of the 10 images was taken as the hollow ratio of the hollow cross-section fiber of the present invention. Further, in order to easily evaluate the hollow ratio, the fiber side surface is observed with a microscope or the like, and the fiber diameter in terms of a circular cross section is measured from the image. The hollow ratio can be calculated by evaluating the ratio of the measured fineness (measured weight) to the fineness (converted weight) converted as a solid fiber from the fiber diameter.

From the viewpoint of lightweight and heat retention, which is the object of the present invention, it is preferable that the bulky structured yarn has a more air layer, and the sheath yarn has a hollow ratio of 30% or more. Within such a range, it is possible to realize a better lightweight property when holding the processed yarn in a bundle, and since it means that an air layer having a lower thermal conductivity is provided, heat retention is also improved. It excels.
As an example of the sea-island composite fiber having this hollow cross section, as shown in FIG. 4, there is a hollow portion (7 in FIG. 4) at the center of the fiber cross section, and island components are scattered among the sea components around it (see FIG. 4-8) Donut type sea-island composite fiber.

As described above, since the hollow portion at the center of the fiber cross section contains air, not only the weight is reduced, but also the heat insulation effect is obtained by exhibiting the heat insulating effect by the air layer included in the hollow portion. Furthermore, due to the sea-island structure around the hollow part, the island component scattered in the sea component disperses the impact against the impact such as compression or bending on the bulky structure yarn, thereby reinforcing the sheath yarn while maintaining its flexibility. This leads to the formation of a bulky structured yarn which is hollow but hard to settle and rich in resilience.

The combination of the polymer used for the island component and the sea component of the sea-island composite fiber used as the sheath yarn is not particularly limited, and can be appropriately selected and used from the above-mentioned polymer group, but has a bulky structure. From the viewpoints of promoting the weight reduction of the yarn and providing the physical properties that can sufficiently withstand the use as a fiber product, it is preferable that the island component is polyolefin and the sea component is polyester. Since polyolefin has a low density, the sea-island composite fiber is highly lightweight when used as an island component. By using polyester as the sea component, the physical properties such as the strength and elongation of the sea-island composite fiber can be made suitable for the fiber product, and since the sea component that is the matrix of the sea-island composite fiber has crystallinity, it can be processed. It is highly resistant to deterioration and fatigue during use. The island/sea composite ratio is preferably 50/50 to 10/90 from the viewpoint of having sufficient physical properties when the sea-island composite fiber is used as a fiber product. Further, from the viewpoint of increasing the low density polyolefin component of the island component to improve the lightness of the sea-island composite fiber, the island/sea composite ratio is more preferably 50/50 to 20/80, and 50/50 to More preferably, it is 30/70.

From the viewpoint of further improving the lightness, which is the object of the present invention, it is possible to promote the low density of the bulky structured yarn and set the density of the bulky structured yarn as a whole to less than 1.00 g/cm ³ . In order to achieve this, it is preferable that the core yarn is a sea-island composite fiber having a core yarn of a fiber having a hollow cross section with a hollow ratio of 10% or more, from the viewpoint of lowering the density like the sheath yarn.

The lower density of the bulky structured yarn leads to a larger volume with the same weight. As a result, many air layers can be formed between the bulky structure yarns, so that it is possible to further improve the lightness and further improve the heat retention due to the heat insulating effect of the air layers.
From the same viewpoint as that of the sheath yarn described above, the hollow ratio of the sea-island composite fiber having a hollow cross section used for the core yarn is more preferably 20% or more, further preferably 30% or more.

In the bulky structured yarn, the sea-island composite fiber having a hollow cross section, which is used for the core yarn, preferably has a three-dimensional crimp from the viewpoint of further improving the texture and suppressing the entanglement. This means that when the yarn is in a free state at the intersection of the core yarns that substantially fixes the sheath yarn, there is an interfilament void due to the intersection of the three-dimensional crimps of the core yarn. Has become. When such a bulky structure yarn has almost no tension, the loop of the sheath yarn can slide sideways in the limited space in the fiber axis direction as well, so that the movable space of the sheath yarn expands and the entanglement suppression and softness of the present invention are suppressed. This is because the effect of texture becomes more remarkable. On the other hand, when tension is applied to the bulky structure yarn, the sheath yarn expands to increase the restraining force at the crossing point, prevent the loop from unraveling, and prevent the sheath yarn from falling off. Demonstrate. The three-dimensional crimp of the core yarn can also be confirmed by observing the core yarn randomly sampled according to the above-described three-dimensional crimp evaluation method for the sheath yarn.

In the present invention, when at least one of the sheath yarn and the core yarn constituting the bulky structure yarn has a three-dimensional crimp, the radius of curvature (r) of the spiral structure formed by the three-dimensional crimp is 1.0 to 30. It is preferably in the range of 0.0 mm. The radius of curvature of the spiral structure referred to here is the same as that used for determining the presence or absence of the three-dimensional crimp as described above, and an image observed two-dimensionally by a digital microscope has a spiral structure. It corresponds to the radius of the perfect circle that is most inscribed at two or more points in the curve formed by the fiber (6 in FIG. 3). Ten randomly selected 10 or more single yarns were selected from each of the processed yarns, and a total of 100 single yarns were obtained by observing each single yarn at a magnification that allows the crimped form to be confirmed with a digital microscope or the like. Measure the thread in millimeters to two decimal places. A simple average of these measured values was calculated, and the value rounded off to the second decimal place was used as the radius of curvature of the three-dimensional crimp structure of the present invention.

The radius of curvature of the spiral structure formed by the three-dimensional crimped structure is more preferably 2.0 to 20.0 mm, and within such a range, the large loop made of the sheath yarn is wound like a spring. It means having a contraction. For this reason, the sheath yarn comes into point contact with the elastic yarn against the compression in the cross-sectional direction of the bulky processed yarn, and the bulkiness is very comfortable. Further, in consideration of the balance with a large loop having a high workability described later, it is particularly preferable that the range in which the effect of the present invention is satisfactorily exhibited is 3.0 to 15.0 mm. Within such a range, the effect of the present invention is effectively exerted when applied to clothing applications in which compression and recovery are repeatedly applied, particularly sports clothing used in a harsh environment, without any problem in long-term durability.

What is effective for this phenomenon is not the two-dimensional bending that can be imparted by mechanical pushing, but the single yarn itself has a three-dimensional three-dimensional shape and has a spiral or similar structure. That is. Conventionally, these crimped forms have been recognized as a structure that is relatively entangled, and have not been incorporated into a sheath yarn. This is a general latent crimp fiber in which the fibers mainly used have fine crimps on the order of microns. In this case, the fine spiral structures may be engaged with each other to promote the fastener effect.

On the other hand, the inventors of the present invention have promoted a study paying attention to the form of the raw yarn in order to achieve the object of the present application to suppress the entanglement of the processed yarns. As a result, it has been discovered that a phenomenon completely opposite to the conventional recognition occurs particularly when a three-dimensional crimp on the order of millimeters is formed in a bulky structured yarn having a large loop. This is because the sheath yarn has a three-dimensional crimp, so that even when the yarn bundle is formed, the bulky structure yarns have the excluded volume and the entanglement is greatly suppressed. It can be considered to be a synergistic effect with the structure of a large loop made of sheath yarn. That is, the sheath yarn of the bulky structure yarn of the present invention has a movable space depending on the size of the loop, and according to the definition of the present invention, a hemisphere having a radius of 1.0 mm or more with the fixed point of the loop as the center. It has a relatively large movable space. In this case, the single yarns having a three-dimensional crimp having an overwhelmingly large size with respect to the fiber diameter are in point contact with each other and repel each other, so that they can exist independently without being entangled. Further, in the case of a filament having a three-dimensional crimp, in addition to the movable space described above, the single yarn itself can further extend in the axial direction of the fiber like a spring. By adding it, it can be unwound easily. It goes without saying that this is a phenomenon unique to the structural form in which the sheath yarn forms a large loop several times to several tens of times larger than the conventional one, like the bulky structured yarn of the present invention. Furthermore, the three-dimensional crimp of the sheath yarn also works effectively from the viewpoint of bulkiness which is a basic characteristic of the present invention. That is, the point contact between the sheath yarns described above produces the effect of repelling each other even within a single processed yarn, and in addition to the initial bulkiness, the state in which the fibers are radially opened in the cross-sectional direction of the processed yarn is maintained over time. You can do it. The spring-like behavior of the radially opened sheath yarn of the present invention is difficult to achieve with conventional simply straight filaments. In addition, the sheath yarns are created by the repulsion of the sheath yarns, and the sheath yarns having the three-dimensional crimps support each other, so that the settling of the sheath yarns can be significantly suppressed.

The morphological feature that the sheath yarn of the present invention forms a large loop and has a three-dimensional crimp structure can be seen as a reduction in the friction coefficient. As described above, this is the effect of contact with other points, and is one of the effects of the bulky structured yarn having the unique structure of the present invention. According to the study by the present inventors, the inter-fiber static friction coefficient is preferably 0.3 or less in order to suppress entanglement between the processed yarns while having bulkiness. The inter-fiber static friction coefficient referred to here is measured by a radar friction coefficient tester in accordance with JIS L 1015 (2010). The inter-fiber static friction coefficient is evaluated by arranging the processed yarns in parallel with the cylinder. When the bulky structured yarn of the present invention is processed into a fiber product, the texture is enhanced when the fibers are appropriately slid and moved during compression. Therefore, the coefficient of static friction between fibers is preferably low, and more preferably 0.2 or less. It is preferably 0.1 or less, and particularly preferably 0.1 or less.

Further, from the viewpoint of appealing a more excellent touch feeling with the bulky structured yarn of the present invention, the single yarn fineness ratio (sheath/core) of the sheath yarn and the core yarn is preferably in the range of 0.5 to 2.0. Within such a range, the densities of the sheath yarn and the core yarn are close to each other, and the yarn can be used without feeling a foreign substance when compressed. Further, as a range in which bulky processing can be efficiently performed, a single yarn fineness ratio (sheath/core) of 0.7 to 1.5 can be mentioned, which is more preferable in that the effect of the present invention becomes more remarkable. Of. Further, in the bulky structured yarn of the present invention, various fibers can be combined, but the core yarn and the sheath do not have any feeling of foreign matter at the time of efficient fluid processing and compression described above. It is preferable that the yarn is a fiber having the same single yarn fineness and mechanical properties. Specifically, in the present invention, it is preferable to prepare two or more drums prepared under the same yarn-making conditions and use them for the core yarn and the sheath yarn.

The bulky structured yarn of the present invention has excellent bulkiness, and it is preferable that the yarn constituting the yarn has an appropriate resilience. This resilience can be viewed as the second moment of area of the fiber, and in view of the effect of the present invention, the single fiber fineness of the synthetic fiber is preferably 3.0 dtex or more. Further, when it is used as a stuffing material, deformation such as compression recovery is repeatedly applied. Therefore, the constituent filaments preferably have appropriate rigidity, and the single yarn fineness is more preferably 6.0 dtex or more. .. The fineness referred to here is a value calculated from the obtained fiber diameter, the number of filaments and the density, or a value obtained by calculating the weight per 10,000 m from a simple average value obtained by measuring the weight of the unit length of the fiber a plurality of times. means.

The bulky structured yarn of the present invention preferably has a breaking strength of 0.5 to 10.0 cN/dtex and an elongation of 5 to 700%. The term "strength" as used herein means a value obtained by calculating the load-elongation curve of the processed yarn under the conditions specified in JIS L1013 (1999), and dividing the load value at break by the initial fineness, and the elongation is It is the value obtained by dividing the elongation at break by the initial test length. Further, the breaking strength of the bulky structured yarn of the present invention is preferably 0.5 cN/dtex or more in order to withstand the process passability of the higher-order processing step and the practical use, and the upper limit of practicability The value is 10.0 cN/dtex. Further, regarding the elongation as well, considering the process passability of the post-processing process, it is preferably 5% or more, and the practicable upper limit value is 700%. The breaking strength and the elongation can be adjusted by controlling the conditions in the manufacturing process according to the intended use. When the bulky structured yarn of the present invention is used for general clothing such as innerwear and outerwear, and bedding such as futons and pillows, the breaking strength is preferably 0.5 to 4.0 cN/dtex. Further, in sports apparel applications and the like where the usage situation is relatively severe, the breaking strength is preferably 1.0 to 6.0 cN/dtex.

The bulky structured yarn of the present invention can be used as various fiber products such as fiber winding packages, tows, cut fibers, cotton, fiber balls, cords, piles, woven and knitted fabrics, and various fiber products. .. The textile products mentioned here include general clothing, sports clothing, clothing materials, interior products such as carpets, sofas and curtains, vehicle interior products such as car seats, cosmetics, cosmetic masks, wiping cloths, and health products. It can be used for environmental and industrial material applications such as filters and hazardous substance removal products. In particular, the bulky structured yarn of the present invention is preferably used as batting because of its bulkiness and the effect of suppressing entanglement. In this case, it is advisable to use a method of forming a bundle of several to several tens of yarns or a sheet-like material such as a non-woven fabric since the side fabric is filled. In particular, when formed into a sheet, it is easy to fill the lateral area and the filling amount can be easily adjusted according to the application. For this reason, it is a lightweight, lightweight, heat-retaining material, and there is no need to worry about it coming off from the side fabric, and there is no need to sew it unnecessarily, so there is no restriction on the form of textile products, and complex designs are possible. Become.

Hereinafter, an example of the method for producing the bulky structured yarn of the present invention will be described in detail.
The core yarn and the sheath yarn used in the present invention may be synthetic fibers obtained by fiberizing a thermoplastic polymer by a melt spinning method. However, in the present invention, the synthetic fiber used for the sheath yarn is a composite fiber, and its density needs to be less than 1.00 g/cm ³ , for example, by combining the composite fiber with a low-density polymer or a hollow cross section. This can be achieved by adopting a structure including

The cross-sectional shape of the synthetic fiber used for the core yarn and the sheath yarn does not need to be particularly limited. By changing the shape of the discharge hole in the spinneret, a general round cross section, a triangular cross section, a Y-shape It can be of an indeterminate shape such as a leaf type, a flat type, a variety type or a hollow type. However, from the viewpoint of expressing the three-dimensional crimp of the sheath yarn, which is a preferable requirement of the present invention, it is also preferable to use a hollow cross section or a side-by-side type composite fiber in which two kinds of polymers are bonded, among the above. Is. That is, it is a preferable mode that a three-dimensional crimp is developed due to the structural difference in the cross-sectional direction by performing heat treatment after performing yarn making and yarn processing. Therefore, at the time of fluid processing, which will be described later, although it is a so-called straight fiber, three-dimensional crimp is developed by performing heat treatment after a large loop forming step using a sheath yarn. If the fibers are straight during bulky processing, the yarn can easily run stably without causing yarn clogging at the nozzle or the like. Further, also in forming the large loop of the present invention, the turning of the core yarn and the sheath yarn is efficiently performed, and the large loop is formed very uniformly in the fiber axis direction of the processed yarn. Become. The sheath yarn develops a three-dimensional crimp by heat-treating the processed yarn in which this large loop is formed in the outer layer, using the textured polymer crystallization temperature as a guide, and becomes the bulky structure yarn of the present invention. .. The three-dimensional crimp of the sheath yarn expresses good bulkiness in both the circumferential direction and the cross-sectional direction of the processed yarn, and it is preferable to control it appropriately according to the desired characteristics. is there. From the viewpoint of controlling the development of crimps after the heat treatment, the fibers used in the present invention more preferably have a hollow cross section. In the case of a hollow cross-section fiber, an air layer having a low thermal conductivity is provided at the center of the fiber. For this reason, for example, after discharging from a spinneret capable of forming a hollow cross section, one side is forcibly cooled with excessive cooling air or the like, or one side is excessively heat-treated with a heating roller or the like during stretching, whereby Therefore, a structural difference occurs, and the size of the three-dimensional crimp can be controlled relatively freely from large size to small size. Therefore, it is suitable for use in the present invention, and from the viewpoint of crimp control by the above-mentioned operation, it is more preferable to have a hollow cross section with a hollow ratio of 20% or more, and to have a hollow cross section with a hollow ratio of 30% or more. Is particularly preferable.

Further, from the viewpoint of maintaining the shape of the fiber and maintaining the shape while promoting the weight reduction, a hollow portion is formed at the center of the fiber cross section as shown in FIG. 4, and a donut-shaped sea-island structure is formed around the hollow part. It is preferable that In this sea-island composite fiber, the hollow part contributes to weight reduction, and the island component of the sea-island structure part acts as a reinforcing material against the sea component, increasing the fiber morphology retention force and bending against compression and compression. Etc. will be suppressed. In addition, if a low density polymer is used for the island component, it will lead to further weight reduction.

The core yarn may be a synthetic fiber composed of a single polymer, but the core yarn is preferably a sea-island composite fiber having the hollow cross section as described above from the same viewpoint as the sheath yarn.
The spinneret used for spinning such a composite fiber is not particularly limited as long as it can polymerize two or more components of polymer, but the position of the hollow cross section and the position of the sea-island structure part are precisely controlled. When it is necessary to do so, the composite mouthpiece composed of a measuring plate and a distribution plate described in JP 2011-174215 A is suitably used. Since the cross-sectional shape can be accurately formed by using this composite spinneret, it is possible to stably obtain the desired fiber cross-sectional shape.

In order to form a doughnut-shaped sea-island structure (island component: polymer A, sea component: polymer B) with a hollow portion in the center of the fiber cross section, the distribution holes in the distribution plate are as described below. It can be achieved by arranging That is, a circular space in which a distribution hole is not formed is provided in the center of the distribution plate, and the distribution holes for the polymer B, which is a sea component, are arranged in an annular shape around the space. A distribution hole for the polymer A is formed on the outer periphery thereof, and one distribution hole for the polymer A is surrounded by six distribution holes for the polymer B serving as a sea component. With this arrangement, the polymer A can be scattered as island components in the sea component formed by the polymer B. Further, since the polymer is not discharged into the circular space in which the distribution hole in the central portion is not formed, the hollow portion is formed.

The ratio of the polymer A as the island component and the polymer B as the sea component used when spinning the conjugate fiber can be selected in the range of 5/95 to 95/5 in terms of A/B ratio based on the discharge amount. .. The A/B ratio is preferably 5/95 to 80/20 from the viewpoint of the formability of the hollow sea island cross section. When the polymer ratio is within such a range, the island component does not fly out to the fiber surface and the hollow portion in the center of the fiber, the sea-island structure is well formed, and the composite fiber has a desired cross section.

The spinning temperature for spinning the synthetic fiber used in the present invention is a temperature at which the polymer used has fluidity. Although the temperature at which the fluidity is exhibited varies depending on the molecular weight, the melting point of the polymer serves as a guide and may be set at the melting point +60° C. or lower. When the amount is less than this, the polymer is not thermally decomposed in the spinning head or the spinning pack, and the decrease in the molecular weight is suppressed, which is preferable. In addition, the discharge amount may be 0.1 g/min/hole to 20.0 g/min/hole per discharge hole as a stable discharge range. At this time, it is preferable to consider the pressure loss in the discharge hole that can ensure the stability of discharge. The pressure loss referred to here is preferably determined from the range of the discharge amount in relation to the melt viscosity of the polymer, the discharge hole diameter, and the discharge hole length, with 0.1 MPa to 40 MPa as a guide.

The molten polymer discharged in this manner is cooled and solidified, and an oil agent is applied to the molten polymer, and the molten polymer is taken up by a roller having a specified peripheral speed to become synthetic fibers. Here, the take-up speed may be determined from the discharge amount and the target fiber diameter, but for stable production, it is preferably in the range of 100 to 7,000 m/min. From the viewpoint that the synthetic fiber is highly oriented and the mechanical properties are improved, the synthetic fiber may be once wound and then stretched, or may be continuously stretched without being once wound. As the drawing conditions, for example, in a drawing machine composed of a pair of rollers, if the fiber is composed of a polymer generally showing a melt-spinnable synthetic fiber, the first roller set to a temperature not lower than the glass transition temperature and not higher than the melting point. According to the peripheral speed ratio of the second roller which is equivalent to the crystallization temperature, the fiber is naturally stretched in the fiber axis direction, heat set, and wound. Further, in the case of a polymer which does not show a glass transition, the dynamic viscoelasticity measurement (tan δ) of the conjugate fiber may be carried out, and the temperature above the peak temperature on the high temperature side of the obtained tan δ may be selected as the preheating temperature. Here, from the viewpoint of increasing the draw ratio and improving the mechanical properties, it is also a suitable means to perform this drawing step in multiple stages.

The bulky structure yarn of the present invention supplies a specified amount of the synthetic fiber (11 in FIG. 5) described above by a supply roller (10 in FIG. 5) having a nip roller or the like, and a suction nozzle (in FIG. 5) capable of jetting compressed air. The first step is to suck the core yarn and the sheath yarn according to 12).
In this suction nozzle (12 in FIG. 5), the flow rate of the compressed air ejected from the nozzle is such that the yarn inserted from the supply roller into the nozzle has the minimum tension and the yarn shakes between the supply roller and the nozzle and within the nozzle. It suffices to inject a flow rate that allows stable traveling without causing the above. The optimum flow rate of the compressed air varies depending on the hole diameter of the suction nozzle used, but as long as thread tension can be applied and a large loop described below can be formed smoothly, the air velocity in the nozzle is 100 m/s. The above is a guideline. The guideline for the upper limit of this air velocity is to be 700 m/s or less, and within this range, the running yarn will not sway due to excessively injected compressed air, and the nozzle will be stable. Will drive inside.

Further, from the viewpoint of preventing disturbance and fiber opening in the nozzle, it is preferable that the jet angle of the compressed air (19 in FIG. 6) is a propelling jet flow that jets the traveling yarn at less than 60°. It is preferable from the viewpoint of high productivity and uniform formation of large loops by the sheath yarn. Naturally, it is not impossible to manufacture the bulky structure yarn of the present invention by processing with a vertical jet flow in which a fluid is jetted at 90° to the running yarn, but the running yarn by jetting the jet flow from the vertical direction From the viewpoint of opening and suppressing the entanglement of single yarns in a narrow space inside the nozzle, processing by a propulsion jet flow is preferable. The processing by the propulsive jet flow can also suppress the formation of short arch-shaped loops that are easily formed in the case of the vertical jet flow in a short cycle.

To form the large loop made of the sheath yarn, which is necessary for the bulky structured yarn of the present invention, it is preferable not to perform disturbance or fiber opening in the suction nozzle. From the viewpoint of running a multifilament composed of several to several tens of yarns in the nozzle without opening the fibers, it is more preferable that the jetting angle of the compressed air is 45° or less with respect to the running yarn. Further, in order to form a large loop outside the nozzle, which will be described later, it is preferable that the stability and the propulsive force of the jet airflow immediately after the nozzle are high. From this viewpoint, the jet angle is 20° with respect to the traveling yarn. The following is particularly preferable.
Next, the second step of the present invention is a step of rotating the yarn sucked by the suction nozzle outside the nozzle to form a large loop by the sheath yarn.

The yarn guided to the suction nozzle may be formed by one feed or two feeds, but it is preferable to perform processing by two feeds in order to manufacture the bulky structure yarn of the present invention. The two feeds referred to here mean a method in which two or more yarns are supplied to the nozzles with different supply speeds (amounts) in advance by a supply roller or the like, and by utilizing the swirling force by the air flow described later. The excessively supplied yarn (sheath yarn) forms a bulky structure in which a large loop is formed in the outer layer. When utilizing these two feeds, it is not impossible to produce a processed yarn having a loop by an interlace processing nozzle or a Taslan processing nozzle that imparts the effect of disturbing, opening and entanglement to the running yarn in the nozzle. Absent. However, in the yarn processed by these processing nozzles, the size of the loop becomes small in addition to the loop being formed in a short cycle. Therefore, in order to produce a bulky structured yarn satisfying the object of the present invention, it is necessary to precisely control many existing parameters, which is very difficult. In addition, when the number of threads is increased, the bulkiness of the processed yarn may differ for each weight. Therefore, from the viewpoint of quality stability, a method that utilizes air flow control outside the nozzle, which will be described later, is used. Is preferred. In this regard, the concept that a large loop can be formed by swirling two yarns supplied at a position apart from the nozzle without giving disturbance and opening treatment in the nozzle, As a result of diligent study from the viewpoint of controlling the air flow ejected from the fiber, a specific result that the sheath yarn turns while opening when the ratio of the air flow velocity to the yarn velocity (air flow velocity/yarn velocity) is 100 to 3000 I discovered a phenomenon.

The airflow velocity referred to here is the velocity of the airflow injected along the traveling yarn from the downstream of the suction nozzle, and can be controlled by the discharge diameter of the nozzle and the flow rate of compressed air. In addition, the yarn speed can be controlled by the orbital speed of a roller that draws the processed yarn after the fluid processing nozzle. Since the turning force of the running yarn increases and decreases depending on the speed ratio between the air flow and the yarn, when the target intersection point of the bulky structure yarn is strengthened, the speed ratio may be close to 3000. On the other hand, if it is desired to make the crossing point slower, the value may be closer to 100. It is possible to change the speed ratio by changing the flow rate of the compressed air intermittently or by changing the speed of the take-off roller, for example. On the other hand, when the bulky structured yarn of the present invention is used in applications such as padding where repeated compression recovery deformation is imparted, it is preferable that the airflow velocity/yarn velocity be 200 to 2000. In particular, in the case of producing a processed yarn used for clothing such as a jacket that is frequently deformed, the airflow velocity/the yarn velocity may be 400 to 1500 from the viewpoint of imparting appropriate restraint and flexibility. Particularly preferred.

The turning point (13 in FIG. 5), which is the base point for developing this turning force, is started by separating the traveling yarn from the accompanying air flow. Specifically, the yarn path may be changed with a bar guide or the like, and the take-up roller (15 in FIG. 5) in the traveling direction of the running yarn pulls the running yarn at a prescribed speed to remove the core yarn. The sheath yarn turns around to form a large loop. From the viewpoint of obtaining a space for causing this swirl and the unraveling due to the vibration of the sheath yarn that utilizes the diffusion of the air flow jetted from the nozzle, the swivel point of the running yarn may be located at a position away from the nozzle discharge port. It is suitable. However, the distance between the nozzle and the turning point, which is suitable for producing the bulky structured yarn of the present invention, changes depending on the velocity of the jetted airflow, and the jetted airflow is from 1.0×10 ⁻⁵ to 1.0×10 ^5. It is preferable that the turning point (13 in FIG. 5) is present while traveling for ^-3 seconds. In order to form the intersecting points of the core yarn and the sheath yarn at an appropriate cycle in balance with the diffusion of the air flow, the distance between the nozzle and the swirling point is such that the jet air flow is 2.0×10 ⁻⁵ to 5.0×10. More preferably it is present during a ⁴ second run.

By adjusting this turning point, the cycle of the intersecting points of the bulky structure yarn of the present invention can be controlled. The crossing point has a role of supporting the independence of the loop made of the sheath yarn, which is a feature of the present invention, and it is preferable that the crossing point exists in a certain period. From this viewpoint, it is preferable to adjust the turning point so that the core yarn and the sheath yarn in the bulky structure yarn are present at 1 to 30 crossing points/mm. Within such a range, even after the three-dimensional crimp of the sheath yarn is developed, the loops are present with an appropriate interval, which is preferable. From this point of view, it is more preferable to adjust the turning points so that the intersection points are present at 5 to 15 points/mm.

The textured yarn (14 in FIG. 5) in which a large loop made of a sheath yarn is formed is subjected to heat treatment after being once wound or after bulking in order to fix the morphology and develop a three-dimensional crimp. Is preferred. In FIG. 5, a processing step of performing heat treatment subsequent to the large loop forming step is illustrated.

This heat treatment (16 in FIG. 5) is performed by heating the processed yarn with a heater or the like, and the processing temperature is the crystallization temperature ±30° C. of the polymer used as a guide. If the treatment is carried out in this temperature range, the treatment temperature is far from the melting point of the polymer, so that there is no fused and cured portion between the sheath yarns or between the core yarns, and there is no feeling of foreign matter and the bulky structured yarn of the present invention It does not impair the good texture of the. As the heater used in this heat treatment step, a general contact type or non-contact type heater can be adopted, but from the viewpoint of bulkiness before heat treatment and deterioration of sheath yarn, a non-contact type heater is preferably adopted. To be done. The non-contact type heater referred to here is an air-heated heater such as a slit type heater or a tube type heater, a steam heater heated by high temperature steam, a halogen heater using radiant heating, a carbon heater, or a microwave heater. To do.

Here, from the viewpoint of heating efficiency, a heater using radiant heating is preferable. Regarding the heating time, for example, the time for fixing the fiber structure of the fibers constituting the processed yarn, fixing the form of the processed yarn, and completing the crimp development of the sheath yarn is a guide, and the heating temperature depends on the treatment temperature and time. It is preferable to make adjustments according to the characteristics required. The processed yarn that has undergone the heat treatment step may be wound with a winder or the like having a tension control function by controlling the speed via a delivery roller (17 in FIG. 5) (18 in FIG. 5). The winding shape is not particularly limited, and so-called cheese winding or bobbin winding can be used. Further, in consideration of processing into a final product, it is possible to combine a plurality of yarns in advance to form a tow or directly form a sheet.

The bulky structured yarn of the present invention preferably has a silicone-based oil agent uniformly attached before and after the heat treatment step. The silicone to be adhered here may be appropriately crosslinked by heat treatment or the like to form a silicone film on the sheath yarn and the core yarn. The silicone-based oil agent mentioned here corresponds to dimethylpolysiloxane, hydrogenmethylpolysiloxane, aminopolysiloxane, epoxypolysiloxane and the like, and these may be used alone or in combination. Further, from the viewpoint of forming a uniform film on the bulky structured yarn, it contains a dispersant, a viscosity modifier, a cross-linking accelerator, an antioxidant, a flame retardant and an antistatic agent as long as it does not impair the purpose of silicone adhesion. Can be made. Although this silicone-based oil agent can be used as an aqueous emulsion even if it is straight, it is preferable to use it as an aqueous emulsion from the viewpoint of uniform adhesion of the oil agent. The silicone-based oil agent is preferably treated by using an oil agent guide, an oiling roller, or spraying so that the silicone-based oil agent can be attached in an amount of 0.1 to 5.0 wt% with respect to the bulky structured yarn in a mass ratio. After that, it is preferable to dry at an arbitrary temperature and time to cause a crosslinking reaction. The silicone-based oil agent can be applied in plural times in a divided manner, and it is also preferable that a strong silicone film is laminated by separately adhering the same type of silicone or different types of silicone. By forming a silicone film on the bulky structured yarn by the above-mentioned treatment, the slipperiness and feel of the bulky structured yarn are increased, and the effect of the present invention can be further enhanced.

The bulky structured yarn of the present invention will be specifically described below with reference to examples.
The following evaluations were performed for the examples and comparative examples.

A. Fineness The weight of 100 m of the fiber was measured and multiplied by 100 to calculate the fineness. This was repeated 10 times, and the value obtained by rounding off the second decimal place of the simple average was taken as the fineness of the fiber. The single yarn fineness was calculated by dividing the above-mentioned fineness by the number of filaments constituting the fiber. In this case as well, the value obtained by rounding off the second decimal place was taken as the single yarn fineness.

B. Mechanical Properties of Fiber The stress-strain curve of the fiber is measured using a tensile tester Tensilon UCT-100 type manufactured by Orientec Co., Ltd. under the conditions of a sample length of 20 cm and a pulling speed of 100%/min. The load at break was read, and the load was divided by the initial fineness to calculate the break strength. Further, the strain at break was read, and the elongation at break was calculated by multiplying the value divided by the sample length by 100. For each value, this operation was repeated 5 times for each level, the simple average value of the obtained results was obtained, and the breaking strength was rounded to the second decimal place, and the breaking elongation was rounded to the first decimal place. The integer value.

C. Density of core yarn and sheath yarn The density of the core yarn and sheath yarn of the bulky structure yarn was measured by a method using a density gradient tube according to JIS L 1013:2010. After the sample reached the equilibrium position in the liquid and stood still, the sedimentation depth of the sample was read to 1 mm from the scale of the density gradient tube, and the numerical value was compared with the correction curve to determine the density. This was repeated twice for each level, the simple average value of the obtained results was calculated, and the value rounded off to the third decimal place was taken as the density.

D. Hollow ratio Fiber having a hollow cross section is cut by a razor in the direction perpendicular to the fiber axis, and the cut surface is two-dimensionally photographed with an electron microscope SU-1510 manufactured by Hitachi High-Technologies Corp. at a magnification that allows 10 or more fibers to be observed. did. Ten randomly selected fibers were extracted from the photographed image, the areas of the fibers and hollow portions were measured using image processing software, and the hollow ratio was calculated as the area ratio by the following formula.
Hollow ratio (%) = (cross-sectional area of hollow part) / (cross-sectional area of fiber (including hollow part))
Each of the 10 images was measured, and the average value of the 10 images was rounded off to the first decimal place to obtain an integer, which was taken as the hollow ratio of the present invention.

E. Loop evaluation (size, intersection, break point)
A load of 0.01 cN/dtex is applied so that slack does not occur in the processed yarn, and the yarn is hooked on a pair of yarn guides with a constant length as illustrated in FIG. The side surface of the thread that was threaded was photographed with a microscope VHX-2000 manufactured by Keyence Corporation at a magnification that allows the entire loop to be observed. The distance from the yarn surface of the loop tip (5 in FIG. 2) was evaluated using image processing software (WINROOF) at 10 locations randomly selected from this image. This operation is performed on a total of 10 images, and 100 points in total are measured in millimeters up to the second decimal point. The average value of these numerical values was calculated, and the value rounded off to the second decimal place was taken as the loop size in the present invention.
The intersection points of the loops and the break points of the sheath yarn were counted at the same 10 points where the loop size was evaluated, and the intersection points and the break points per millimeter were evaluated. The same operation was performed on 10 images, and the average value of 100 places was rounded off to the nearest whole number, and the integer value was evaluated as an intersection point. Regarding the break points of the loops, the break points of the counted loops were averaged and the second decimal point was rounded off to obtain the break point of the loop. Here, the sample having a breaking point of less than 0.2 pieces/mm is assumed to have continuous loops referred to in the present invention, and is not broken (evaluation: ◯). Was evaluated as having breakage (evaluation: x).

F. Crimp form evaluation (three-dimensional crimp, radius of curvature)
Ten or more single yarns were sampled at each of 10 randomly selected from the processed yarns, and each single yarn was observed with a Keyence Corporation microscope VHX-2000 at a magnification at which the crimped form can be confirmed. did. In this image, when the observed single yarn has a spirally wound form, it is judged that a three-dimensional crimp structure is present (evaluation: ◯), and when the observed single yarn has a straight form, the crimped structure is obtained. It was judged that there was no condensed structure (evaluation: x). In addition, from the same image, the radius of the perfect circle that is most inscribed at two or more locations in the curvature of the crimped fiber (6 in FIG. 3) was evaluated using image processing software (WINROOF). As described above, a total of 100 single yarns randomly selected are measured in millimeters to the second decimal point, and the value obtained by rounding off the second decimal point of the simple average is the three-dimensional crimp structure of the present invention. The radius of curvature of

G. Inter-fiber static friction coefficient It is measured by a radar friction coefficient tester according to a method according to JIS L 1015 (2010). The inter-fiber static friction coefficient is evaluated by arranging the processed yarns in parallel with the cylinder. The static friction coefficient between fibers is a value obtained by rounding off the second decimal place of the measured value.

H. Unwindability (Zipper phenomenon suppression effect)
A drum wound with a processed yarn of 500 m or more was set on a creel, released for 5 minutes at a speed of 30 m/min in the cross-sectional direction of the drum, and the dance of the yarn due to the fastener phenomenon, catching, etc. were visually confirmed, and evaluated in the following four stages. ..

⊚: No yarn dance is observed, and the unwinding property is excellent.

◯: A slight yarn dance can be seen, but it can be unwound satisfactorily.

Δ: A thread dance and a slight catching are seen, but it can be unraveled.

X: The thread dances and gets caught and cannot be unwound.

I. Tactile sensation A drum in which the processed yarn is wound for 500 m or more is set on a creel, and the yarn is unwound in a cross-sectional direction of the drum using a measuring machine to form a wound form, thereby forming a 10 m yarn cassette. A sample for texture evaluation was prepared by fixing one portion of the thread cassette. The touch feeling when gripping this sample was evaluated according to the following four grades.

⊚: A texture with excellent flexibility.

◯: A texture with good flexibility.

Δ: A texture having flexibility.

X: Poor texture with no flexibility and feeling of foreign matter.

J. Evaluation of Bulkiness of Bulky Structure Yarn 20 g of a bulky structure yarn is filled in a cylindrical container having an inner diameter of 28.8 cm and a height of 50.0 cm, and a load of 0.15 g/cm ² from the top in the vertical direction with respect to the filled bulky structure yarn. measuring the height H (cm) of space bulky structure yarn occupied when multiplied by calculates the bulkiness (in 3 / ^20g) from the following equation, an integer value obtained by rounding off the first decimal place of the value Was made bulky.
Bulky ^{(in 3 /20g)=(14.4 2 π / 2.54} 3) × H.

Example 1
Polypropylene (PP:MFR=9 g/10 min) as an island component is melted at 265° C. and polyethylene terephthalate (PET:0.65 dl/g) as a sea component separately at 300° C., melted, weighed, and allowed to flow into a spinning pack. At a spin block temperature of 280° C., a hollow sea-island composite yarn having a hollow part at the center of the fiber cross section and a donut-shaped sea-island structure was melt-spun. As the spinneret incorporated in the spinning pack, a composite spinneret including a measuring plate and a distribution plate described in JP2011-174215A is used, and a circular space in which a distribution hole is not formed is provided in the center of the plate as the distribution plate. The distribution holes of the sea component polymer were arranged in an annular shape around the circumference, and the distribution hole of the sea component polymer was surrounded by 6 holes per one distribution hole of the island component polymer. .. The composite polymer stream discharged at a composite ratio of island/sea=30/70 is blown from one side with a cooling air of 20° C. at a flow rate of 100 m/min, cooled and solidified, and then an oil agent is applied, and the undrawn yarn is spun at 1200 m/min. After being wound up, it was drawn 2.9 times at a drawing speed of 600 m/min between rollers heated to 90° C. and 130° C., with a fineness of 78 dtex, a filament number of 12, 12 islands per filament, and a hollow ratio of 30. % And a density of 0.87 g/cm ³ was drawn.
The obtained hollow sea-island composite yarn is fed to the two supply rollers one by one in the process illustrated in FIG. 5, one supply roller at a speed of 50 m/min and the other at a speed of 1000 m. /Min, and suctioned with a suction nozzle. In the suction nozzle, compressed air was jetted at 20° to the running yarn at an air velocity of 400 m/s, and was jetted from the nozzle together with the accompanying airflow so that the core yarn and the sheath yarn did not intersect. The yarn jetted from the nozzle was run together with the air flow for 1.0×10 ^-4 seconds, the yarn path was changed using the ceramic guide, and the yarn was formed into a large loop consisting of sheath yarn, and a take-up roller made 50 m/ I took it in min.
Subsequently, the processed yarn was guided to a tube heater through a roller and heat-treated with heated air at 150° C. for 10 seconds to set the morphology of the bulky structure yarn and to develop a three-dimensional crimp in the sheath yarn. The bulky structure yarn was wound around a drum at 52 m/min by a tension control type winding machine installed after the tube heater. Further, a silicone oil containing polysiloxane at a concentration of 8 wt% was applied to the collected bulky structure yarns by spraying evenly so that the final polysiloxane adhesion amount was 1 wt% with respect to the bulky structure yarns. The textured yarn was collected by heat treatment for 20 minutes at a temperature of °C.
The bulky structured yarn collected in Example 1 had a structure in which large loops composed of sheath yarns were projected from the surface of the yarn by 21.0 mm on average, and the large loops were formed at a frequency of 10 pieces/mm. .. The protruding loop had excellent size and cycle uniformity.
The core yarn and the sheath yarn have a three-dimensional crimp structure with a radius of curvature of 4.5 mm on the order of millimeters, and a large loop of the sheath yarn has a continuous loop formed without any breakage. It was (Break point: 0.0)
In the bulky structure yarn, the sheath yarn forming a continuous large loop has a three-dimensional crimp structure, the coefficient of static friction between fibers is 0.1, and the unwinding from the wound drum is very high. It was smooth and had excellent unwinding property (unwinding property: ◎). Further, it had bulkiness derived from the specific structure of the present invention and had a texture excellent in flexibility (texture: ⊚). In the bulky evaluation, it took a bulky and excellent 628in ³ / 20g. The results are shown in Table 1.

Examples 2, 3
The hollow sea-island composite yarn used for the sheath yarn has a composite ratio of island/sea and a density of the drawn yarn of island/sea=20/80 and density 0.90 g/cm ³ (Example 2), island/sea=10/90. And the density was changed to 0.93 g/cm ³ (Example 3).
The bulky structured yarn collected in Example 2 was one in which a large loop of the sheath yarn formed a continuous loop with no breakage. The sheath yarn has a three-dimensional crimp structure and is excellent in unwinding property from the wound drum (unwinding property: ◎), and has excellent soft texture. There was (texture: ◎). In the bulky evaluation, it took a bulky and excellent 606in ³ / 20g.
The bulky structured yarn collected in Example 3 was one in which a large loop of the sheath yarn formed a continuous loop in which no breakage point was found. The sheath yarn has a three-dimensional crimp structure and is excellent in unwinding property from the wound drum (unwinding property: ◎), and has excellent soft texture. There was (texture: ◎). In the bulky evaluation, it exerted a good bulkiness and 582in ³ / 20g. The results are shown in Table 1.

Example 4
Example 1 was carried out except that the hollow ratio of the hollow sea-island composite yarn used for the sheath yarn was changed to 20% and the density of the drawn yarn was changed to 0.99 g/cm ³ .
The bulky structure yarn collected was a continuous loop in which no breakage was found in the large loop of the sheath yarn. The sheath yarn has a three-dimensional crimped structure, has good unwindability from the wound drum (unwindability: ○), and has a texture with excellent flexibility. There was (texture: ◎). In the bulky evaluation, and they exhibit sufficient bulkiness and 554in ³ / 20g. The results are shown in Table 1.

Example 5
Example except that the island/sea composite ratio of the hollow sea-island composite yarn used for the sheath yarn was changed to 50/50, the hollow ratio was changed to 20%, and the density of the drawn yarn was changed to 0.98 g/cm ^3. It carried out according to 1.
The bulky structure yarn collected was a continuous loop in which no breakage was found in the large loop of the sheath yarn. The sheath yarn has a three-dimensional crimped structure, has good unwindability from the wound drum (unwindability: ○), and has a texture with excellent flexibility. There was (texture: ◎). In addition, the evaluation of bulkiness showed a sufficient bulkiness of 563 in ³ /20 g. The results are shown in Table 1.

Comparative Example 1
Example 1 was carried out except that the hollow ratio of the hollow sea-island composite yarn used for the sheath yarn was changed to 8% and the density of the drawn yarn was changed to 1.14 g/cm ³ .
The bulky structure yarn collected was a continuous loop in which no breakage was found in the large loop of the sheath yarn. The sheath yarn had a three-dimensional crimped structure, was excellent in unwinding from the wound drum (unwinding: ◎), and had a good texture in flexibility (( Texture: ◎). On the other hand, in the bulky evaluation, 457in ³ / 20g and bulky it was unsatisfactory. The results are shown in Table 1.

Comparative example 2
Example except that the island/sea composite ratio of the hollow sea-island composite yarn used for the sheath yarn was changed to 5/95, the hollow ratio was changed to 20%, and the density of the drawn yarn was changed to 1.09 g/cm ^3. It carried out according to 1.

The bulky structure yarn collected was a continuous loop in which no breakage was found in the large loop of the sheath yarn. The sheath yarn had a three-dimensional crimped structure, was excellent in unwinding from the wound drum (unwinding: ◎), and had a good texture in flexibility (( Texture: ◎). On the other hand, in the bulky evaluation, 504in ³ / 20g and bulky it was unsatisfactory. The results are shown in Table 1.

Comparative Example 3
In order to verify the effect of the bulky processing of the present invention, the procedure was carried out in accordance with Example 1 except that a nozzle in which the injection angle of the compressed air was changed to 90° was used and a turning point by the ceramic guide was not provided.
The collected bulky structure yarn had a smaller loop size due to the sheath yarn before the heat treatment as compared with Example 1, and was formed in a very short cycle. Therefore, when the sheath yarn is crimped by heat treatment, loops can be formed in the yarn, but the bulkiness is poor. When the details of the loop composed of the sheath yarn were confirmed, irregularities were found in the loop size, and relatively many breaking points that could not be confirmed before the heat treatment were observed (breakage: breaking point 0.5). Although it had a soft texture (texture: △), the unwinding property from the wound drum was poor (unwinding property: x) due to the occurrence of yarn dance and catching. The results are shown in Table 1.

Example 6
Polyethylene terephthalate (PET: IV=0.65 dl/g) was melted at 290° C., then weighed and allowed to flow into a spinning pack, and three slits as illustrated in FIG. 7 (width 0.1 mm, 17 in FIG. 7). Was discharged from the discharge holes for hollow cross sections arranged concentrically so that the hollow ratio was 30%. A 20° C. cooling air was blown onto the discharged yarn at a flow rate of 100 m/min from one side to cool and solidify, then a nonionic spinning oil agent was applied, and an undrawn yarn was wound at a spinning speed of 1500 m/min. Subsequently, the wound undrawn yarn was drawn 3.0 times at a drawing speed of 800 m/min between rollers heated to 90° C. and 140° C. to obtain a drawn yarn having a fineness of 78 dtex, a filament number of 12, and a hollow ratio of 30%. Example 1 was repeated except that this drawn yarn was used as the core yarn.
The bulky structure yarn collected was a continuous loop in which no breakage was found in the large loop of the sheath yarn. The sheath yarn has a three-dimensional crimped structure, was excellent in unwindability from the wound drum (unwindability: ◎), and had a good softness (texture). :○). In the bulky evaluation, it exerted a good bulkiness and 591in ³ / 20g. The results are shown in Table 2.

Example 7
The spinning spinneret was changed to have 12 round holes so as to have a general round cross-section fiber, and a drawn yarn of polyethylene terephthalate alone was collected under the same conditions as in Example 6. All procedures were carried out according to Example 1 except that the drawn yarn was used as the core yarn.

The bulky structure yarn collected was a continuous loop in which no breakage was found in the large loop of the sheath yarn. The sheath yarn has a three-dimensional crimped structure, was excellent in unwindability from the wound drum (unwindability: ◎), and had a good softness (texture). :○). In the bulky evaluation, it exerted a good bulkiness and 579in ³ / 20g. The results are shown in Table 2.

Comparative Example 4
A bulky structured yarn was processed according to Example 1 except that polyethylene terephthalate alone was used for both the core and the sheath and the hollow fiber had a hollow ratio of 30%.

The bulky structure yarn collected was a continuous loop in which no breakage was found in the large loop of the sheath yarn. The sheath yarn had a three-dimensional crimped structure, was excellent in unwinding from the wound drum (unwinding: ◎), and had a good texture in flexibility (( Texture: ◎). On the other hand, in the bulky evaluation, bulkiness is insufficient and 540in ³ / 20g. The results are shown in Table 2.

Comparative Example 5
A bulky structured yarn was processed according to Example 1 except that a polyethylene terephthalate single yarn whose core and sheath were not hollow was used.
The bulky structure yarn collected was a continuous loop in which no breakage was found in the large loop of the sheath yarn. The sheath yarn has a three-dimensional crimped structure, has an excellent unwindability from the wound drum (unwindability: ◎), and has a good texture (texture). :○). On the other hand, in the bulky evaluation, bulkiness is insufficient and 533in ³ / 20g. The results are shown in Table 2.

Examples 8-10
The procedure of Example 1 was repeated, except that the air velocity in the fluid processing was changed to 350 m/s (Example 8), 175 m/s (Example 9), and 88 m/s (Example 10).

The bulky structured yarn collected in Example 8 had a structure in which a large loop made of a sheath yarn protruded from the yarn surface by 60.0 mm on average, and formed a continuous loop without any breakage point. The unwindability from the wound drum was excellent (unwindability: ◎), and the texture was excellent in flexibility (touch: ◎). In addition, it exerted a bulky and excellent 603in ³ / 20g is a bulky evaluation.

The bulky structured yarn collected in Example 9 had a structure in which a large loop made of a sheath yarn protruded from the yarn surface by an average of 70.0 mm, and a continuous loop in which no breakage point was observed was formed. The unwinding property from the wound drum was good (unwinding property: ○), and the softness was also good (feeling: ○). In addition, it exerted a bulky and excellent 607in ³ / 20g is a bulky evaluation.

The bulky structured yarn collected in Example 10 had a structure in which a large loop made of a sheath yarn protruded from the yarn surface by 100.0 mm on average, and a continuous loop in which no breakage point was observed was formed. From the wound drum, thread dance and slight catching were seen, but it was unwindable (unwindability: △) and had a texture with sufficient flexibility (feel: △). In addition, it exerted a bulky and excellent 612in ³ / 20g is a bulky evaluation. The results are shown in Table 3.

Examples 11 and 12
The procedure was carried out according to Example 1 except that the injection angle of the compressed air in the fluid processing was changed to 55° (Example 11) and 45° (Example 12).
The bulky structured yarn collected in Example 11 had a structure in which a large loop made of a sheath yarn protruded from the yarn surface by 3.0 mm on average, and a continuous loop in which no breakage point was observed was formed. The unwinding property from the wound drum was excellent (unwinding property: ◎), and the texture had good flexibility (feeling: ○). The bulkiness evaluation showed a good bulkiness of 573 in ³ /20 g.
The bulky structured yarn collected in Example 12 had a structure in which a large loop made of a sheath yarn protruded from the yarn surface by 5.0 mm on average, and a continuous loop having no breakage point was formed. The unwindability from the wound drum was excellent (unwindability: ◎), and the texture had excellent flexibility (touch: ◎). In addition, it exerted a bulky and excellent 600in ³ / 20g is a bulky evaluation. The results are shown in Table 3.

Examples 13-17
The single yarn fineness of the hollow sea-island composite yarn used for the sheath yarn is changed so that the single yarn fineness ratio (sheath/yarn) is 2.0 (Example 13), 1.5 (Example 14), 0.7 (Example). Example 15), 0.5 (Example 16), and 0.3 (Example 17), except that the procedure of Example 1 was repeated.

The bulky structured yarn collected in Example 13 was a large loop of the sheath yarn in which continuous loops without breakage were formed, and the radius of curvature of the loop was 1.3 mm. The unwinding property from the wound drum was excellent (unwinding property: ◎), and the texture had sufficient flexibility (feeling: △). The bulkiness evaluation was 550 in ³ /20 g, which was a sufficient bulkiness.

The bulky structure yarn collected in Example 14 was a large loop of the sheath yarn in which continuous loops without breakage were formed, and the radius of curvature of the loop was 2.2 mm. The unwinding property from the wound drum was excellent (unwinding property: ◎), and the texture had good flexibility (feeling: ○). The bulkiness evaluation showed a good bulkiness of 573 in ³ /20 g.

The bulky structure yarn collected in Example 15 was a large loop of the sheath yarn in which a continuous loop in which no breakage point was observed was formed, and the radius of curvature of the loop was 14.4 mm. The unwindability from the wound drum was excellent (unwindability: ◎), and the texture was also excellent in flexibility (touch: ◎). In addition, it exerted a bulky and excellent 614in ³ / 20g is a bulky evaluation.

The bulky structured yarn collected in Example 16 was a large loop of the sheath yarn in which a continuous loop in which no breakage point was observed was formed, and the radius of curvature of the loop was 19.4 mm. The unwinding property from the wound drum was good (unwinding property: ○), and the softness was also good (feeling: ○). The bulkiness evaluation showed a good bulkiness of 582 in ³ /20 g.
The bulky structured yarn collected in Example 17 was a large loop of the sheath yarn in which continuous loops without breakage were formed, and the radius of curvature of the loop was 19.4 mm. From the wound drum, thread dance and slight catching were seen, but it could be unwound (unwindability: △), and the texture had good flexibility (feel: ○). Further, bulky and 557in ³ / 20g it was sufficient in bulky evaluation. The results are shown in Table 4.

Examples 18-20
At the swirl points of the traveling yarns, the jet airflow was 9.0×10 ⁻⁴ seconds (Example 18), 4.8×10 ⁻⁴ seconds (Example 19), and 1.2×10 ⁻⁵ seconds (Example), respectively. 20) Carried out according to Example 1 except that it was adjusted to be present while running.
The bulky structure yarn sampled in Example 18 was able to be unwound although the yarn was dancing and slightly caught (unwinding property: Δ), and had a good soft texture (feeling: ○). ). Also showed bulky and excellent 616in ³ / 20g in bulky evaluation.
The bulky structured yarn collected in Example 19 had excellent unwinding property from the wound drum (unwinding property: ◎), and also had a soft texture (feeling: ◎). In addition, the bulky evaluation, took a bulky and excellent 603in ³ / 20g.
The bulky structured yarn collected in Example 20 could be unwound smoothly from the wound drum (unwinding property: ◎). In addition, the texture was good to the touch (feel: O). The bulky evaluation showed sufficient bulkiness and 561in ³ / 20g. The results are shown in Table 5.

Example 21
The procedure of Example 1 was repeated, except that the collected bulky structure yarn was not subjected to the application of the silicone-based oil agent containing polysiloxane and the heat treatment for fixing the silicone.
The collected bulky structure yarn had a coefficient of static friction between fibers of 0.3, good unwindability from the wound drum (unwindability: ○), and good softness (feel) :○). Also in the bulky evaluation took a bulky and excellent 624in ³ / 20g. The results are shown in Table 5.

The bulky structure yarn of the present invention has a soft texture, is lightweight, has excellent heat retention, is difficult to be entangled with each other, and has excellent handleability during molding processing. Suitable for batting, stuffed cotton, etc.

1 sheath yarn 2 core yarn 3 yarn surface 4 yarn guide 5 distance from yarn surface 6 three-dimensional crimp 7 hollow part 8 island component 9 sea component 10 supply roller 11 synthetic fiber 12 suction nozzle 13 turning point 14 processed yarn 15 Take-up roller 16 Heater 17 Delivery roller 18 Winder 19 Compressed air injection angle 20 Slit-shaped ejection hole

Claims (6)

In a bulky structured yarn consisting of a core yarn that substantially fixes the sheath yarn by intersecting the sheath yarn forming the loop and the sheath yarn, the sheath yarn forms a continuous loop without breaking , The bulky structured yarn, wherein the size of the loop is 1.0 mm to 100.0 mm , and the sheath yarn is a composite fiber having a density of less than 1.00 g/cm ³ . The bulky structured yarn according to claim 1, wherein the sheath yarn has a three-dimensional crimp. The bulky structured yarn according to claim 1 or 2, wherein the sheath yarn is a sea-island composite fiber having a hollow cross section with a hollow ratio of 10% or more. The bulky structured yarn according to any one of claims 1 to 3, wherein the core yarn is a sea-island composite fiber having a hollow cross section with a hollow ratio of 10% or more, and has a three-dimensional crimp. The bulky structured yarn according to claim 3, wherein the island component of the sea-island composite fiber is polyolefin and the sea component is polyester. A fiber product containing the bulky structure yarn according to any one of claims 1 to 5 in at least a part thereof.