Fiber bundle for artificial hair

Abstract

The present invention provides a fiber bundle for artificial hair that, when used in a two-bundle twist, produces more favorable ends and root-side volume than past fiber bundles.　The present invention includes first fibers and second fibers that are shorter than the first fibers and has, in the longitudinal direction, a mixed region in which the first fibers and the second fibers are mixed and a first fiber region that is at an end part and is at least 95% the first fibers. A first ratio that is the ratio of the cross-sectional area of cross-sections of the first fibers that are orthogonal to the extension direction of the first fibers to the area of the smallest enclosing circles of the cross-sections is at least 0.7, and a second ratio that is the ratio of the cross-sectional area of cross-sections of the second fibers that are orthogonal to the extension direction of the second fibers to the area of the smallest enclosing circles of the cross-sections is no more than 0.6.

Description

Fiber bundle for artificial hair

[0001] The present invention relates to a fiber bundle for artificial hair.

[0002] Conventionally, fiber bundles for artificial hair imitating human hair have been used as materials for headdress products such as blade hair (for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2010-47846

[0004] By the way, fiber bundles for artificial hair used in hairstyles incorporating hair such as blade hair, dreadlocks, and cornrow hair are required to satisfy the functions such as the volume when braided on the head of the subject and the knotting of the hair tips (difficulty in unraveling the hair tips, hair entanglement) in a balanced manner.

[0005] Therefore, an object of the present invention is to provide a fiber bundle for artificial hair that can be braided into a two-strand braid with better hair entanglement and volume on the root side compared to the conventional ones.

[0006] When the present inventors studied to solve the above problems, in order to improve the volume per unit weight, if fibers with a large cross-sectional spread are used, the distance between the centers of the fibers becomes large and an improvement in the volume increase rate can be expected. However, when the cross-sectional spread is increased, voids and cavities become large and it becomes easy to deform, so it easily undergoes plastic deformation and the hair entanglement tends to deteriorate. On the other hand, in order to improve the hair entanglement, it is considered that the cross-sectional spread can be reduced to increase the density, and since it easily returns to its original position regardless of the direction of deformation, an improvement in hair entanglement can be expected. However, when the cross-sectional spread is reduced, the volume on the root side tends to be small. Therefore, the present inventors used at least two types of fibers, one with a large cross-sectional spread and the other with a small cross-sectional spread, with different lengths, and increased the volume on the root side by mixing the fiber with a large cross-sectional spread and the fiber with a small cross-sectional spread on the root side, and considered that the hair entanglement on the hair tip side could be improved by forming the hair tip side substantially only with the fiber with a small cross-sectional spread.

[0007] One aspect of the present invention derived from the above considerations is a fiber bundle for artificial hair having a first fiber and a second fiber shorter than the first fiber, wherein in the longitudinal direction, the bundle has a mixed region where the first fiber and the second fiber are mixed and a first fiber region at the end where the first fiber accounts for 95% or more, the first fiber having a first ratio of 0.7 or more, where the cross-sectional area of ​​the first fiber is the ratio of the cross-sectional area to the area of ​​the smallest inclusion circle in the cross-section perpendicular to the extension direction of the first fiber, and the second fiber having a second ratio of 0.6 or less, where the cross-sectional area of ​​the second fiber is the ratio of the cross-sectional area to the area of ​​the smallest inclusion circle in the cross-section perpendicular to the extension direction of the second fiber.

[0008] In this context, "smallest inclusion circle" refers to the smallest circle that encompasses all parts (sets).

[0009] According to this pattern, the first fiber has a large first ratio of 0.7 or more, so even if it is elastically deformed, it easily returns to its original shape due to its restorative force, resulting in good hair retention and making it difficult for stray hairs to form. According to this pattern, the second fiber has a second ratio of 0.6 or less, which is smaller than the first ratio, so the ratio of cavities and voids can be increased, making it easier to increase volume in the mixed region.

[0010] A preferred configuration is when the difference between the first ratio of the first fiber and the second ratio of the second fiber is 0.2 or greater.

[0011] A preferred feature is that the minimum inclusion circle of the second fiber has a larger diameter than the minimum inclusion circle of the first fiber.

[0012] A preferred configuration is that the second fiber is C-shaped or Y-shaped.

[0013] A preferred feature is that the first fiber has a circular or polygonal shape in the cross-sectional area perpendicular to the extension direction of the first fiber, with a circularity of 0.85 or more.

[0014] Here, "circularity" refers to the degree of circularity, and is calculated as 4π × (area) ÷ (perimeter). ２ It is expressed as follows: For example, the circularity of the first fiber is calculated by taking a cross-sectional photograph of the first fiber and dividing it by 4π × (number of pixels in the cross-section) ÷ (perimeter of the cross-section). ２ It can be calculated by performing the following calculation.

[0015] A preferred configuration is that the first fiber is composed of an acrylic fiber or a polypropylene fiber.

[0016] The term "acrylic fiber" as used herein includes not only acrylic fibers made of polymers containing 85% or more acrylonitrile-derived structural units, but also modacrylic fibers made of polymers containing 35% to less than 85% by mass of acrylonitrile-derived structural units.

[0017] The aspects described above can be dependent on each other, refer to some of their components, or substitute for some of their components, as long as they fall within the technical scope of the present invention.

[0018] According to the present invention, when braiding two strands of hair, it is possible to create a braid that holds the hair in place better and has more volume at the roots compared to conventional methods.

[0019] This is a front view of a fiber bundle for artificial hair according to the first embodiment of the present invention. This is a plan view of the fiber bundle for artificial hair of Figure 1 unfolded and straightened out. This is a plan view of the fiber bundle for artificial hair according to the second embodiment of the present invention unfolded and straightened out. This is an explanatory diagram of the measurement position in volume increase rate measurement and stray hair measurement. These are the measurement results of bulk and stray hair for Examples 1 and 2 and Comparative Examples 1 to 3, where (a) is a figure representing the measurement result of Example 1, (b) is a figure representing the measurement result of Example 2, (c) is a figure representing the measurement result of Comparative Example 1, (d) is a figure representing the measurement result of Comparative Example 2, and (e) is a figure representing the measurement result of Comparative Example 3.

[0020] Embodiments of the present invention will be described in detail below.

[0021] The first embodiment of the present invention, a fiber bundle 1 for artificial hair, is suitably used as a head ornament for braided hairstyles such as braided hair, dreadlocks, and cornrows. The fiber bundle 1 for artificial hair is a fiber bundle in which multiple types of fibers 2 and 3 of different lengths are bundled together, and as shown in Figure 1, the central part is fixed with a fixing means such as a rubber band, and it is used by folding the central part fixed with the fixing means. As shown in Figure 2, when the fiber bundle 1 for artificial hair is unfolded into a planar shape, each fiber 2 and 3 extends in a predetermined direction (hereinafter simply referred to as the longitudinal direction L). As shown in Figure 2, the fiber bundle 1 for artificial hair has a mixed region 10 in the longitudinal direction L when unfolded into a planar shape, in which the first fiber 2 and the second fiber 3 are mixed, and first fiber regions 11a and 11b to which only the first fiber 2 belongs.

[0022] <First Fiber 2> As shown in the enlarged view of Figure 2, the first fiber 2 has a circular or polygonal shape with a circularity of 0.85 or more in the cross-sectional shape (hereinafter also referred to as the first cross-section) perpendicular to the extension direction (extension direction of the central axis), and is a solid with a solid interior. The ratio of the cross-sectional area to the area of ​​the smallest inclusion circle C1 (hereinafter also referred to as the first ratio) of the first fiber 2 is 0.7 or more. If the cross-sectional shape of the first fiber 2 is an n-sided polygon, it is preferable that n is an even number of 6 or more. The cross-sectional shape of the first fiber 2 may also be a star-shaped polygon such as a star-shaped hexagon.

[0023] Preferably, the first fiber 2 has the same bendability in the forward direction F1 and the reverse direction R1 in a first direction perpendicular to the extension direction, as shown in the enlarged view of Figure 2, and preferably has the same bendability in the forward direction F2 and the reverse direction R2 in a second direction perpendicular to the extension direction and also perpendicular to the first direction.

[0024] It is preferable that the centroid of the cross-section of the first fiber 2 substantially coincides with the center of the minimum inclusion circle C1 of the cross-section perpendicular to the extension direction of the first fiber 2. That is, it is preferable that the centroid of the cross-section of the first fiber 2 perpendicular to the extension direction of the first fiber 2 is within 40 μm from the center of the minimum inclusion circle C1. The first fiber 2 is not particularly limited in terms of material, but it is preferably composed of acrylic fibers or polypropylene fibers (PP fibers), and more preferably composed of modacrylic fibers (MODA fibers). It is preferable that crimp is formed in most of the longitudinal direction L of the first fiber 2, and more preferably that crimp is formed throughout. The average pitch of the crimp is preferably 1.5 mm or more and 15 mm or less, and more preferably 3 mm or more. The first fiber 2 is a long fiber with a longer longitudinal length L than the second fiber 3.

[0025] From the viewpoint of improving the FA ratio and ease of knitting, the diameter of the minimum inclusion circle C1 per unit fineness of the first fiber 2 is preferably 1.75 or more and less than 2.5, and more preferably 2.4 or less.

[0026] <Second Fiber 3> The second fiber 3 is not particularly limited in terms of material, but it is preferably composed of acrylic fibers, and more preferably of modacrylic fibers. The second fiber 3 may be made of a different material than the first fiber 2, for example, polypropylene fibers or polyethylene terephthalate fibers can be used. It is preferable that the second fiber 3 is made of the same type of fiber as the first fiber 2. As shown in the enlarged view of Figure 2, the second fiber 3 has a cross-sectional shape (hereinafter also referred to as the second cross-section) perpendicular to the extension direction (extension direction of the central axis) which is "Y" shaped, and the second cross-section comprises a nodal point portion 20 and extended portions 21a to 21c extending in three directions from the nodal point portion 20. The nodal point portion 20 of the second fiber 3 is positioned at a location corresponding to the centroid of a triangle, and the extended portions 21a to 21c extend toward the vertices of the triangle.

[0027] The second fiber 3 is less likely to bend in the direction in which the stretched portions 21a to 21c extend, and more likely to bend in the opposite direction compared to the direction in which the stretched portions 21a to 21c extend. In the mixed region 10, it is preferable that the diameter of the smallest inclusion circle C2 of the second cross-section of the second fiber 3 is greater than or equal to the diameter of the smallest inclusion circle C1 of the first cross-section of the first fiber 2, and is even more preferable than the diameter of the smallest inclusion circle C1 of the first cross-section of the first fiber 2. It is preferable that the ratio of the cross-sectional area to the area of ​​the smallest inclusion circle C2 of the cross-section perpendicular to the extension direction of the second fiber 3 (hereinafter also referred to as the second ratio) is 0.6 or less, and is smaller than the ratio of the cross-sectional area to the area of ​​the smallest inclusion circle C1 of the cross-section perpendicular to the extension direction of the fiber 2 (first ratio). The difference in ratio between the first ratio and the second ratio is preferably 0.7 or less, more preferably 0.5 or less, and even more preferably 0.3 or less. The difference in ratio between the first ratio and the second ratio is preferably 0.01 or more, more preferably 0.1 or more, and even more preferably 0.2 or more. The second fiber 3 preferably has crimp formed over most of its longitudinal direction L, and preferably has crimp formed throughout. The crimp preferably has an average pitch of 1.5 mm or more and 15 mm or less. The second fiber 3 is a short fiber whose length in the longitudinal direction L is shorter than the length in the longitudinal direction L of the first fiber 2.

[0028] The second fiber 3 preferably has a minimum inclusion circle C2 diameter per unit fineness that is larger than the minimum inclusion circle C1 diameter per unit fineness of the first fiber 2, and more preferably is 1.8 or more and 2.6 or less.

[0029] <Mixed Region 10> The mixed region 10 is a region where the first fiber 2 and the second fiber 3 are mixed together. Preferably, the length L in the longitudinal direction of the mixed region 10 is 1.02 times or more and 15 times or less the length L in the longitudinal direction of the first fiber regions 11a and 11b.

[0030] <First Fiber Regions 11a, 11b> The first fiber regions 11a and 11b are regions where only the first fiber 2 exists, and are regions that constitute the respective ends of the artificial hair fiber bundle 1. The length L in the longitudinal direction of the first fiber regions 11a and 11b is preferably 20 cm or more and 300 cm or less. The lengths L in the longitudinal direction of the first fiber regions 11a and 11b are preferably the same, but they may be different.

[0031] As shown in Figure 4, the fiber bundle 1 for artificial hair preferably has a stray hair rate (FA rate) at a position 15 cm from the tip (end position) when braided into two strands, which is greater than 0% and less than or equal to 50%, and more preferably less than or equal to 40%.

[0032] In this embodiment of the artificial hair fiber bundle 1, since the cross-sectional contour shape of the first fiber 2 is circular or polygonal, even when deformed, it does not easily reach plastic deformation but remains elastic deformation, and it easily returns to its original state due to its elastic restorative force. As a result, the hair stays in place well and it is difficult for stray hairs to form. In this embodiment of the artificial hair fiber bundle 1, since the diameter of the minimum inclusion circle C2 of the cross-section of the second fiber 3 is greater than or equal to the diameter of the minimum inclusion circle C1 of the cross-section of the first fiber 2, it is easy to increase the volume in the mixed region 10. In this embodiment of the artificial hair fiber bundle 1, since 95% or more of the first fiber regions 11a and 11b at the ends are composed of acrylic fibers, by performing a so-called hot water set, which involves immersing the bundle in warm water at a temperature above the glass transition temperature or softening temperature of acrylic fibers (for example, 80 degrees Celsius), it is possible to create a bundled hair end.

[0033] In the artificial hair fiber bundle 1 of this embodiment, the first fiber 2 is preferably solid. This provides a core that is less prone to plastic deformation, resulting in better hair retention.

[0034] In the artificial hair fiber bundle 1 of this embodiment, the length L in the longitudinal direction of the first fiber regions 11a and 11b is preferably 20 cm or more and 300 cm or less. This allows for a shape that has volume at the root end and tapers towards the tip like a brush.

[0035] In the artificial hair fiber bundle 1 of this embodiment, it is preferable that the minimum inclusion circle C2 of the second fiber 3 has a larger diameter than the minimum inclusion circle C1 of the first fiber 2. This allows for greater volume.

[0036] In the artificial hair fiber bundle 1 of this embodiment, it is preferable that the second fiber 3 has a directional tendency to bend. This makes it easier for the second fiber 3 to bend significantly in the direction in which it is most likely to bend and undergo plastic deformation, and a space is easily created between it and the first fiber 2.

[0037] In the artificial hair fiber bundle 1 of this embodiment, the second fiber 3 is preferably composed of acrylic fiber or polypropylene fiber. This minimizes the difference in feel between the second fiber 3 and the first fiber 2.

[0038] According to the artificial hair fiber bundle 1 of this embodiment, the first fiber 2 has the same flexibility in the forward direction F1, F2 and the reverse direction R1, R2 in two orthogonal directions. Therefore, even if it undergoes elastic deformation, it easily returns to its original shape due to its restorative force, resulting in good hair retention and making it difficult for stray hairs to form.

[0039] In the artificial hair fiber bundle 1 of this embodiment, it is preferable that the ratio of the cross-sectional area of ​​the first fiber 2 to the area of ​​the smallest inclusion circle C1 in the cross-section perpendicular to the extension direction of the first fiber 2 is 0.7 or more. This makes it easier for the fiber to return to its original shape due to its restorative force even after elastic deformation, resulting in good hair retention and making it difficult for stray hairs to form. In the artificial hair fiber bundle 1 of this embodiment, it is preferable that the ratio of the cross-sectional area of ​​the second fiber 3 to the area of ​​the smallest inclusion circle C2 in the cross-section perpendicular to the extension direction of the second fiber 3 is 0.6 or less. This makes it possible to increase the ratio of voids and air pockets, and makes it easier to increase the volume in the mixed region 10.

[0040] Next, a second embodiment of the present invention, specifically the fiber bundle 101 for artificial hair, will be described.

[0041] As shown in Figure 3, the fiber bundle 101 for artificial hair comprises a first fiber 2 and a second fiber 103, and the shape of the second fiber 103 differs from that of the second fiber 3 in the first embodiment.

[0042] As shown in the enlarged view of FIG. 3, the second fiber 103 has a "C" - shaped cross - sectional shape and is hollow inside, with a communication groove 110 that connects the inside and the outside. That is, in the depth direction of the communication groove 110, the second fiber 103 is more likely to bend toward the communication groove 110 side (the opening side) and less likely to bend toward the side opposite to the communication groove 110 side.

[0043] In the above - described embodiments, the cross - sectional shapes of the second fibers 3 and 103 were Y - shaped or C - shaped, but the present invention is not limited thereto. The cross - sectional shape of the second fibers 3 and 103 may be other shapes, and it is preferable that they are line - symmetric and not point - symmetric.

[0044] As long as the above - described embodiments are within the technical scope of the present invention, each component can be freely replaced or added between the embodiments.

[0045] Hereinafter, the present invention will be specifically described by way of examples. Note that the present invention is not limited to the following examples and can be appropriately modified and implemented without changing the gist thereof.

[0046] (Example 1)First, the first fiber with a circular cross-sectional shape (round shape) (circularity: 0.91, minimum circumscribed circle diameter: 64 μm, first ratio: 0.79, modacrylic fiber (hereinafter also simply referred to as MODA)) was bundled to a length of 3000 mm and a total weight of 400 g to form a first raw fiber bundle. With the pressure kept constant, the first raw fiber bundle was passed through a gear crimper with a gear part full tooth size of 2.5 mm under the conditions of a gear temperature of 100 °C and a speed of 1 m / min to form a first fiber bundle with crimps. Then, the first fiber bundle was combed and defibrated on a needle bed like a pincushion. Similarly, the second fiber with a Y-shaped cross-sectional shape (minimum circumscribed circle diameter: 140 μm, second ratio: 0.27, MODA) was bundled to a length of 3000 mm and a total weight of 400 g to form a second raw fiber bundle. Under the same conditions as the first raw fiber bundle, a second fiber bundle with crimps was formed, and the second fiber bundle was combed and defibrated on a needle bed like a pincushion. Subsequently, the defibrated first fiber bundle was cut to a fixed length of 42 inches, and the defibrated second fiber bundle was cut to a fixed length of 27 inches. These two types of fiber bundles with different lengths were weighed in a ratio of 5:5 based on their total weight. To make the fiber tips pen-shaped, the fiber bundles were combed on a needle bed like a pincushion to a total length of 48 inches. Then, 7 g was weighed from the fiber bundle with a total length of 48 inches, and a fiber cord formed by a two-ply process was formed. The fiber cord thus formed was taken as Example 1.

[0047] (Example 2) A fiber cord obtained in the same manner as in Example 1, except that the second fiber with a C-shaped cross-sectional shape (minimum circumscribed circle diameter: 93 μm, second ratio: 0.56, MODA) was used, was taken as Example 2. [[ID=!]]

[0048] (Example 3) A fiber cord obtained in the same manner as in Example 1, except that the first fiber with a circular cross-sectional shape (minimum circumscribed circle diameter: 90 μm, circularity: 0.93, first ratio: 0.90, polypropylene fiber (hereinafter also simply referred to as PP)) was used, was taken as Example 3.

[0049] (Example 4) A fiber cord obtained in the same manner as in Example 2, except that the first fiber with a circular cross-sectional shape (minimum circumscribed circle diameter: 90 μm, circularity: 0.93, first ratio: 0.90, PP) was used, was taken as Example 4.

[0050] (Comparative Example 1) Comparative Example 1 was a fiber cord obtained in the same manner as in Example 1, except that a first fiber with an H-shaped cross-section (minimum inclusion circle diameter of 80 μm, first ratio of 0.65, MODA) was used.

[0051] (Comparative Example 2) Comparative Example 2 was obtained in the same manner as in Example 1, except that a first fiber with a Y-shaped cross-section (minimum inclusion circle diameter 140 μm, first ratio 0.27, MODA) was used.

[0052] (Comparative Example 3) Comparative Example 3 was obtained in the same manner as in Comparative Example 1, except that a second fiber with an H-shaped cross-section (minimum inclusion circle diameter 80 μm, second ratio 0.65, MODA) was used.

[0053] (Comparative Example 4) Comparative Example 4 was obtained in the same manner as in Example 1, except that a first fiber with an elliptical cross-sectional shape (minimum inclusion circle diameter 95 μm, circularity 0.71, first ratio 0.40, MODA) was used.

[0054] (Comparative Example 5) Comparative Example 5 was obtained in the same manner as in Example 2, except that a first fiber with an elliptical cross-sectional shape (minimum inclusion circle diameter 95 μm, circularity 0.71, first ratio 0.40, MODA) was used.

[0055] (Volume Increase Rate Measurement) In the fiber cords of each of Examples 1 and 2 and each of Comparative Examples 1 to 3, a hair bundle volume measuring device (manufactured by BOSSA NOVA Vision, product name: BOLERO) was used to irradiate light from 5 cm to 15 cm from the root (base position) as shown in Figure 4, and the bulk volume (cm) of the portion with a transmittance of less than 50% was measured. ３ The volume was measured. The volume increase rate is the percentage change in volume (%) between the fiber cords of each example 1 to 4 and comparative examples 1, 2, 4, and 5 and the fiber cord of comparative example 3 when braided in two.

[0056] (Measurement of Flyaway Hair Rate) In the fiber cords of each of Examples 1 to 4 and Comparative Examples 1 to 5, the flyaway hair rate (hereinafter also referred to as the FA rate) was measured using a hair bundle volume measuring device (manufactured by BOSSA NOVA Vision, product name: BOLERO) with a threshold of 50%. Specifically, light was irradiated at a position 15 cm from the hair tip (0 cm) of the fiber cord shown in Figure 4, and the portion with a transmittance of less than 50% was classified as bulk, and the portion with a transmittance of 50% or more was classified as flyaway hair, and the ratio of flyaway hair to the total was measured.

[0057] (Ease of knitting) 7g was weighed from a 48-inch length fiber bundle, and a professional beauty evaluator sensory-evaluated the resistance of the fiber bundle to bouncing back when braided in two. Comparative Example 2 was scored 2 points, Comparative Example 3 was scored 3 points, and a score of 5 points was assigned based on the degree of bounce, with the level of resistance to bounce (ease of knitting) being the highest.

[0058] First, Figure 5 shows the measurement results for each of Examples 1 and 2 and each of Comparative Examples 1 to 3, and Table 1 shows the measurement results for each of Examples 1 to 4 and each of Comparative Examples 1 to 5. Note that the ratio difference represents the difference between the first ratio of the first fiber and the second ratio of the second fiber.

[0059]

[0060] Examples 1 to 4, which used a first fiber with an area ratio of 0.7 or more, showed a smaller FA ratio and improved ease of knitting compared to Comparative Examples 1 to 5, which had an area ratio of 0.65 or less. Examples 1 to 4 and Comparative Examples 1, 2, 4, and 5, which used a second fiber with an area ratio of 0.6 or less, showed a larger volume increase rate compared to Comparative Example 3, which used a second fiber with an area ratio of 0.65 or more. Examples 1 to 4, in which the minimum inclusion circle diameter per unit fineness of the first fiber was 1.75 or more and 2.4 or less, showed a smaller FA ratio and improved ease of knitting compared to Comparative Examples 1 to 5.

[0061] In Examples 1 to 4, where the difference in the area ratio between the first and second fibers was 0.2 or more, compared to Comparative Example 3, which used the same type of fiber, there were fewer stray hairs, the FA rate was suppressed, and the ease of knitting was also improved, as shown in Figure 5. In Comparative Example 1, where an H-shaped fiber was used as the first fiber (long fiber) and a Y-shaped fiber was used as the second fiber (short fiber), the volume increase rate increased compared to Comparative Example 3, where both the first and second fibers were H-shaped fibers, and the FA rate and ease of knitting slightly deteriorated. This suggests that using a Y-shaped fiber as the second fiber increases volume.

[0062] In Comparative Example 2, where both the first and second fibers were Y-shaped, the volume increase rate was greater, the FA ratio worsened significantly, and the ease of knitting also deteriorated compared to Comparative Example 1, where the first fiber was H-shaped and the second fiber was Y-shaped. This suggests that while Y-shaped fibers are effective in increasing volume, they worsen the FA ratio and ease of knitting.

[0063] In Example 1, where a circular fiber was used as the first fiber and a Y-shaped fiber was used as the second fiber, the volume increase rate and FA rate were improved compared to Comparative Example 1, where an H-shaped fiber was used as the first fiber and a Y-shaped fiber was used as the second fiber, and the ease of knitting was also improved. From this, it was found that by using a circular fiber as the first fiber, the FA rate can be improved without reducing the volume increase rate, and the ease of knitting can also be improved.

[0064] In Example 2, which used a circular fiber as the first fiber and a C-shaped fiber as the second fiber, the volume increase rate was about the same as in Example 1, which used a circular fiber as the first fiber and a Y-shaped fiber as the second fiber, while the FA rate and ease of knitting were further improved.

[0065] Examples 3 and 4, which used circular PP fibers as the first fiber, showed good volume increase rate, FA rate, and ease of knitting, similar to Examples 1 and 2, which used circular MODA fibers as the first fiber.

[0066] This suggests that even when using PP fibers as the first fiber, it is possible to form a fiber bundle for artificial hair of good quality, similar to when using MODA fibers.

[0067] In Examples 1 and 3, where a circular fiber with a circularity of 0.85 or higher was used as the first fiber and a Y-shaped fiber was used as the second fiber, the volume increase rate was about the same as in Comparative Example 4, where an elliptical fiber with a circularity of 0.71 was used as the first fiber and a Y-shaped fiber was used as the second fiber, while both the fabric-to-weave ratio and ease of knitting were improved. Furthermore, in Examples 2 and 4, where a circular fiber with a circularity of 0.85 or higher was used as the first fiber and a C-shaped fiber was used as the second fiber, the volume increase rate, fabric-to-weave ratio, and ease of knitting were all improved compared to Comparative Example 5, where an elliptical fiber with a circularity of 0.71 was used as the first fiber and a C-shaped fiber was used as the second fiber. These results suggest that the closer the first fiber is to a perfect circle, the better the volume increase rate, fabric-to-weave ratio, and ease of knitting.

[0068] From the above results, it was found that by using round-shaped fibers as the long-fiber first fibers and Y-shaped or C-shaped fibers as the short-fiber second fibers, it is possible to improve volume, reduce the FA rate, and improve ease of knitting. Furthermore, it was found that by using first fibers with an area ratio of 0.7 or more and second fibers with an area ratio of 0.6 or less, it is possible to improve volume, reduce the FA rate, and improve ease of knitting. Based on the above, it was suggested that in the mixed region of first and second fibers at the root, using fibers with cavities or voids and a large cross-sectional area as the second fibers creates distance between each fiber, making it possible to improve volume per unit weight at the root. In addition, it was suggested that in the first-fiber region at the tip of the hair, using fibers with a small cross-sectional area as the first fibers makes it easier for the fibers to return to their original position in any direction, making it difficult for stray hairs to form and improving hair accumulation.

[0069] 1,101 Fiber bundle for artificial hair 2 First fiber 3,103 Second fiber 10 Mixed region 11a,11b First fiber region

Claims

1. A fiber bundle for artificial hair having a first fiber and a second fiber shorter than the first fiber, wherein in the longitudinal direction, the bundle has a mixed region where the first fiber and the second fiber are mixed, and a first fiber region at the end where the first fiber accounts for 95% or more, the first fiber having a first ratio of 0.7 or more, where the second fiber has a second ratio of 0.6 or less, where the second fiber has a second ratio of 0.6 or less, where the second fiber has a cross-sectional area of ​​0.6 or less, where the second fiber has a cross-sectional area of ​​0.6 or less, where the second fiber has a cross-sectional area of ​​0.6 or less, where the second fiber has a cross-sectional area of ​​0.6 or less, where the second fiber has a cross-sectional area of ​​0.6 or less, where the second fiber has a cross-sectional area of ​​0.6 or less, 2. The fiber bundle for artificial hair according to claim 1, wherein the difference between the first ratio of the first fiber and the second ratio of the second fiber is 0.2 or more.

3. The fiber bundle for artificial hair according to claim 1 or 2, wherein the minimum inclusion circle of the second fiber has a larger diameter than the minimum inclusion circle of the first fiber.

4. The fiber bundle for artificial hair according to claim 1 or 2, wherein the second fiber is C-shaped or Y-shaped.

5. The fiber bundle for artificial hair according to claim 1 or 2, wherein the first fiber has a circular or polygonal shape in the cross-sectional area perpendicular to the extension direction of the first fiber, with a circularity of 0.85 or more.

6. The fiber bundle for artificial hair according to claim 1 or 2, wherein the first fiber is composed of an acrylic fiber or a polypropylene fiber.

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