Artificial hair and method for manufacturing artificial hair

Abstract

The present invention provides: artificial hair which is capable of achieving both better volume when braided and more favorable braid stops at the hair tips than the prior art; and a method for manufacturing the artificial hair.　The present invention has a fiber bundle having large crimp parts with a minimum pitch of 1-7 mm, and the large crimp parts comprise small crimp parts near one peak section thereof, the small crimp parts having a smaller pitch than the pitch of the large crimp parts. With this configuration, it is easier for the small crimp parts to be entangled with each other, and it is possible to achieve both volume when braided and more favorable braid stops at the hair tips.

Description

Artificial hair and method for manufacturing artificial hair

[0001] The present invention relates to artificial hair and a method for producing artificial hair.

[0002] Artificial hair fiber bundles that imitate human hair have been used as materials for head accessories such as wigs, hair extensions, braids, and hair bands (see, for example, Patent Document 1). For example, the artificial hair fiber bundle in Patent Document 1 has volume at the ends of the hair and resembles human hair by crimping the resin fibers with gear crimping.

[0003] JP 2010-47846 A

[0004] Incidentally, in order to give a braid a large volume, it is preferable to provide a large crimp, but on the other hand, providing a large crimp widens the pitch and makes the hair closer to straight, which causes the problem of the fibers not staying in place when braiding or the like.

[0005] Therefore, an object of the present invention is to provide artificial hair and a method for manufacturing artificial hair that can achieve both volume when braided and good braiding at the ends compared to conventional methods.

[0006] One aspect of the present invention for solving the above-mentioned problems is artificial hair having a fiber bundle having large-crimped portions with a minimum pitch of 1 mm or more and 7 mm or less, the large-crimped portions including small-crimped portions in the vicinity of one crimped portion, the small-crimped portions having a pitch smaller than that of the large-crimped portions.

[0007] The term "pitch" as used herein refers to the distance between adjacent crests or valleys. The same applies hereinafter. The term "nearby" as used herein refers to a range within 1 / 4 of the minimum pitch of the large crimped portion.

[0008] According to this aspect, since the small crimped portions are provided near the peaks of the large crimped portions, the small crimped portions are more likely to entangle with each other, making it easier to maintain volume when braided and allowing the ends of the hair to be braided in a good position.

[0009] In a preferred aspect, the large crimped portions have a minimum pitch of 3 mm or less.

[0010] In a preferred aspect, the fiber bundle has a bending degree of 1.2 or more and 1.3 or less.

[0011] The term "flexibility" as used herein refers to the ratio of the total length of the fiber, taking into account crimp, to the overall length of the fiber in the elongation direction, ignoring crimp. In other words, the term "flexibility" refers to the ratio of the maximum length of the fiber when stretched to its natural length.

[0012] In a preferred aspect, the fiber bundle has an average fly-out rate of 23% or less in a portion 10 cm from the end of the hair when braided.

[0013] The term "stray hairs" as used herein refers to a state in which short fibers protrude from the surface of a fiber bundle, as shown in Figure 5. In other words, the "stray hair rate" is an index showing the degree of stray hairs in a fiber bundle when braided, and refers to the percentage of stray hairs in the total when classified into bulk, where the rate of transmitted light when irradiated with light is less than 50%, and stray hairs, where the rate of transmitted light is 50% or more.

[0014] In a preferred aspect, the fiber bundle is made of at least one kind of raw fiber selected from the group consisting of acrylic fiber, polyvinyl chloride fiber, polypropylene fiber, and polyethylene terephthalate fiber.

[0015] In a more preferred aspect, the fiber bundles are made of modacrylic fibers.

[0016] One aspect of the present invention is a method for producing artificial hair, which includes a small-crimp imparting step in which raw material fibers are imparted with small-crimp portions in a heated small-crimp imparting section to form work-in-progress fibers, and a large-crimp imparting step in which large-crimp portions are imparted to the work-in-progress fibers in a heated large-crimp imparting section, and the large-crimp imparting step involves heating at a temperature lower than that of the small-crimp imparting step.

[0017] According to this aspect, large crimped portions can be formed while maintaining small crimped portions, and artificial hair can be produced that has both volume when braided and good braiding properties at the ends compared to conventional methods.

[0018] In a preferred aspect, the small crimp imparting step is carried out before the large crimp imparting step.

[0019] In a preferred aspect, the small crimp-imparting portion and the large crimp-imparting portion are both gear crimps, and the difference in total tooth height is 1 mm or more.

[0020] The term "total tooth depth" used here refers to the distance from the tooth base to the tooth tip.

[0021] In a preferred aspect, the small crimp imparting section and the large crimp imparting section are both gear crimps, the total tooth height of the gear of the large crimp imparting section is 3.0 mm or less, and the difference in total tooth height of the gear of the small crimp imparting section and the large crimp imparting section is less than 3.0 mm.

[0022] In a preferred aspect, the ratio of the volume when a predetermined weight of the raw fiber is braided to the volume when the same weight of the raw fiber after the large crimp imparting step is braided is 115% or more.

[0023] According to the present invention, it is possible to achieve both volume when braiding and good braiding of the ends of the hair compared to conventional methods.

[0024] 1 is an explanatory diagram of the artificial hair of the first embodiment of the present invention, (a) is a perspective view showing the artificial hair as a model, (b) is a side view of region A in (a), and (c) is a side view of region B in (b). FIG. 2 is a side view showing a model of a manufacturing apparatus suitable for manufacturing the artificial hair of FIG. 1. FIG. 3 is an explanatory diagram for measuring the volume increase rate (bulk) and the degree of bending, (a) is a perspective view showing the state in which the fibers are placed on a horizontal plane, and (b) is a cross-sectional view of (a). FIG. 4 is an explanatory diagram for measuring the volume increase rate (braid), (a) is a perspective view of the fiber bundle, and (b) is a cross-sectional view of plane M in (a). FIG. 5 is an explanatory diagram for the fly-out hair rate.

[0025] Hereinafter, embodiments of the present invention will be described in detail.

[0026] The artificial hair 1 of the first embodiment of the present invention is artificial hair for braiding, and is mainly suitable for use in braiding. As shown in Figure 1(a), the artificial hair 1 has a fiber bundle 2 in which a plurality of fibers 5 are bundled. The fiber bundle 2 extends in a predetermined bundle shape, and has large crimped portions 10 that have amplitude in the direction crossing the longitudinal direction and extend in a wavy shape in the longitudinal direction.

[0027] As shown in Figure 1(b), the large crimped portions 10 are formed by regularly repeating first peaks 15 and first valleys 16. The minimum pitch of the large crimped portions 10 (the distance D1 between adjacent first peaks 15, 15 or the distance D2 between adjacent first valleys 16, 16) is preferably 1 mm or more, more preferably 1.5 mm or more, and even more preferably 1.75 mm or more. The minimum pitch of the large crimped portions 10 is preferably 7 mm or less, more preferably 3.5 mm or less, even more preferably 3 mm or less, and particularly preferably 2.5 mm or less. The minimum amplitude of the large crimped portions 10 (the length L1 from the bottom of a first valley 16 to the peak of a first peak 15) is preferably 0.30 mm or more, and more preferably 0.38 mm or more. The minimum amplitude of the large-crimped portion 10 (the length L1 from the bottom of the first valley portion 16 to the peak of the first peak portion 15) is preferably less than 7 mm, more preferably 4 mm or less, even more preferably 2 mm or less, particularly preferably 1.40 mm or less, and even more preferably 0.49 mm or less. The large-crimped portion 10 has small-crimped portions 11 throughout the entire length.

[0028] The small-crimped portions 11 are crimps formed over the entire large-crimped portions 10, and as shown in Figure 1(c), have a smaller amplitude and period than the large-crimped portions 10. The small-crimped portions 11 are formed by repeating second peaks 17 and second valleys 18 in a generally regular pattern. The minimum pitch of the small-crimped portions 11 (the distance D3 between adjacent second peaks 17, 17 or the distance D4 between adjacent second valleys 18, 18) is preferably smaller than the minimum pitch of the large-crimped portions 10. The minimum pitch of the small-crimped portions 11 (the distance D3 between adjacent second peaks 17, 17 or the distance D4 between adjacent second valleys 18, 18) is preferably 1.0 mm or greater. The minimum pitch of the micro-crimped portions 11 is preferably 7 mm or less, more preferably 3.5 mm or less, even more preferably 3 mm or less, and particularly preferably 2.5 mm or less. The minimum amplitude of the micro-crimped portions 11 (the length L2 from the bottom of the second valley portion 18 to the apex of the second peak portion 17) is preferably smaller than the minimum amplitude of the large-crimped portions 10. The minimum amplitude of the micro-crimped portions 11 (the length L2 from the bottom of the second valley portion 18 to the apex of the second peak portion 17) is preferably greater than 0 mm, preferably 0.30 mm or more, and more preferably 0.38 mm or more. The minimum amplitude of the micro-crimped portions 11 is preferably less than 7 mm, more preferably 4 mm or less, even more preferably 2 mm or less, particularly preferably 1.40 mm or less, and particularly more preferably 0.49 mm or less.

[0029] In the fiber bundle 2, the fibers 5 are preferably composed of at least one type of raw fiber selected from the group consisting of acrylic fibers, polyvinyl chloride fibers, polypropylene fibers, and polyethylene terephthalate fibers, and more preferably modacrylic fibers. The cross-sectional shape of the fibers 5 is not particularly limited, and may be, for example, circular, Y-shaped, H-shaped, U-shaped, C-shaped, X-shaped, flat, or the like.

[0030] Next, a manufacturing device 30 suitable for manufacturing the artificial hair 1 of this embodiment will be described.

[0031] The manufacturing apparatus 30 is a crimp forming apparatus that forms crimp sections 10, 11 on raw fiber material to form a fiber bundle 2, and as shown in Figure 2, it is equipped with a small crimp imparting section 31, a large crimp imparting section 32, and a conveying roller section 33.

[0032] The small crimp-imparting section 31 is a gear crimp and is composed of a pair of meshed first gear sections 35a, 35b. The pitch S1 of the first gear sections 35a, 35b is preferably 1.0 mm or more and 4.0 mm or less. The total tooth depth T1 of the first gear sections 35a, 35b is preferably greater than 0 mm, and more preferably 1.0 mm or more. The total tooth depth T1 of the first gear sections 35a, 35b is preferably less than 7 mm, more preferably 4.0 mm or less, even more preferably less than 3.0 mm, and particularly preferably 2 mm or less.

[0033] The large crimp imparting section 32 is a gear crimp and is composed of a pair of meshed second gear sections 36a, 36b. The second gear sections 36a, 36b are gears having a total tooth depth T2 greater than the total tooth depth T1 of the first gear sections 35a, 35b. The pitch S2 of the second gear sections 36a, 36b is preferably 1 mm or greater, more preferably 1.5 mm or greater, and even more preferably 1.75 mm or greater. The pitch S2 of the second gear sections 36a, 36b is preferably 7.0 mm or less, more preferably 3 mm or less, and even more preferably 2.5 mm or less. The total tooth depth T2 of the second gear sections 36a, 36b is preferably 1 mm or greater but 7 mm or less, and even more preferably 4 mm or less. The difference between the total tooth depth T2 of the second gear portions 36a, 36b and the total tooth depth T1 of the first gear portions 35a, 35b is preferably 1 mm or more and 4 mm or less, more preferably 2.5 mm or less, and even more preferably 1.5 mm or less.

[0034] The transport roller section 33 transports the raw fiber between the large crimp imparting section 32 and the small crimp imparting section 31 at a predetermined speed.

[0035] Next, a method for manufacturing the artificial hair 1 recommended when manufacturing the artificial hair 1 of this embodiment using the manufacturing device 30 will be described.

[0036] First, a bundle of raw fibers (hereinafter also referred to as raw fiber bundle) is passed through the micro-crimp imparting section 31 heated by the conveying roller section 33 to impart the micro-crimp section 11, thereby forming a fiber bundle in progress (micro-crimp imparting process).

[0037] At this time, the heating temperature in the micro-crimp imparting section 31 (the temperature of the first gear sections 35a, 35b) is preferably 95° C. or higher and 100° C. or lower. The passing speed through the micro-crimp imparting section 31 is preferably 0.5 m / min. or higher and 8.0 m / min. or lower.

[0038] The in-process fiber bundle is passed through a large crimp imparting section 32 heated by a conveying roller section 33 to impart large crimps 10 thereto, thereby forming a fiber bundle 2 (large crimp imparting step).

[0039] In this case, the in-process fiber bundle is heated in the large-crimp imparting step at a temperature lower than that in the small-crimping step. That is, the heating temperature in the large-crimp imparting section 32 (the temperature of the second gear sections 36a, 36b) is lower than the heating temperature in the small-crimp imparting section 31 (the temperature of the first gear sections 35a, 35b), and is preferably 80°C or higher and 90°C or lower from the viewpoint of maintaining the shape of the small-crimp section 11. The passing speed in the large-crimp imparting section 32 is preferably 0.5 m / min or higher and 8.0 m / min or lower. The passing speed in the small-crimp imparting section 31 and the passing speed in the large-crimp imparting section 32 may be the same or different.

[0040] Next, the physical properties of the artificial hair 1 of this embodiment will be described.

[0041] In the artificial hair 1, the ratio (degree of curvature) of the length of the fiber bundle 2 to the length of the raw fiber bundle is preferably 1.2 or more and 1.3 or less, and more preferably 1.23 or more and 1.25 or less. In the artificial hair 1, when the fiber bundle 2 is braided, the product of the width and thickness at a portion 10 cm from the tip is preferably 65% ​​or more, more preferably 115% or more, and even more preferably 117% or more of the product of the width and thickness of the raw fiber bundle when braided. In the artificial hair 1, when the fiber bundle 2 is braided, the product of the width and thickness at a portion 10 cm from the tip is preferably 200% or less, more preferably 150% or less, and even more preferably 148% or less of the product of the width and thickness of the raw fiber bundle when braided. In the artificial hair 1, the bulk of the fiber bundle 2 is preferably 180% or more, more preferably 200% or more, and even more preferably 250% or more of the bulk of the raw fiber bundle of the same weight. The bulk of the fiber bundle 2 of the artificial hair 1 is preferably 520% ​​or less, more preferably 500% or less, and even more preferably 425% or less of the bulk of the raw fiber bundle of the same weight. ３ The arithmetic mean flyaway rate (FLYAWAY) per knitting strand is preferably 0% or more and 40% or less, more preferably 23% or less, and from the viewpoint of achieving better knitting finish, even more preferably 22% or less. The arithmetic mean flyaway rate (FLYAWAY) can be, for example, the arithmetic mean value of 10 measurements.

[0042] According to the artificial hair 1 of this embodiment, the adjacent small crimped portions 11, 11 are close to each other near one of the first peaks 15 of the large crimped portion 10, so the small crimped portions 11, 11 are easily entangled with each other, making it easier to maintain the volume of the braid and ensuring good braiding at the ends.

[0043] According to the manufacturing method of the artificial hair 1 of this embodiment, the large crimping process is carried out after the small crimping process, and in the large crimping process, the work fiber is heated at a temperature lower than that in the small crimping process, so that both the volume of the braid and good braiding at the ends can be achieved.

[0044] In the above embodiment, the small crimp imparting unit 31 has a pair of first gear portions 35a, 35b, but the present invention is not limited to this. The small crimp imparting unit 31 may have multiple pairs of first gear portions 35a, 35b. Similarly, in the above embodiment, the large crimp imparting unit 32 has a pair of second gear portions 36a, 36b, but the present invention is not limited to this. The large crimp imparting unit 32 may have multiple pairs of second gear portions 36a, 36b.

[0045] In the above embodiment, two types of crimped portions 10, 11, large and small, are formed by two types of crimping portions 31, 32 with different gear sizes, but the present invention is not limited to this. Three or more types of crimped portions may be formed by three or more types of crimping portions 31, 32 with different gear sizes.

[0046] In the above embodiment, a plurality of raw fibers are bundled together to form a raw fiber bundle, which is then passed through the crimp-imparting sections 31, 32 to impart crimps 10, 11 to the raw fiber bundle, but the present invention is not limited to this. The raw fibers may also be passed through the crimp-imparting sections 31, 32 one by one without being bundled, to impart crimps 10, 11 to the raw fibers, thereby forming the fiber bundle 2.

[0047] In the above embodiment, the crimped portions 10, 11 are formed over the entire longitudinal direction of the fiber bundle 2, but the present invention is not limited to this. The crimped portions 10, 11 may be formed only in a portion of the longitudinal direction of the fiber bundle 2. Also, in the above embodiment, the small-crimped portions 11 are formed over the entire large-crimped portion 10, but the present invention is not limited to this. The small-crimped portions 11 may be formed only in a portion of the large-crimped portion 10.

[0048] In the above-described embodiments, each component can be freely substituted or added between the respective embodiments as long as it falls within the technical scope of the present invention.

[0049] EXAMPLES The present invention will be specifically explained below with reference to examples and comparative examples, but the present invention is not limited to these examples.

[0050] Example 1: Modacrylic fiber was used as the raw fiber, and a raw fiber bundle obtained by bundling raw fibers was passed through a first gear section with a total tooth depth of 1.5 mm under a constant pressure, a set temperature of 140°C, a gear temperature of 95°C to 100°C, and a passing speed of 0.5 m / min to 8.0 m / min. The fiber bundle was then passed through a second gear section with a total tooth depth of 2.5 mm under a constant pressure, a set temperature of 120°C, a gear temperature of 80°C to 90°C, and a passing speed of 0.5 m / min to 8.0 m / min, forming large and small crimped portions. The fiber bundle thus obtained was designated Example 1.

[0051] Example 2 Example 2 was prepared in the same manner as in Example 1, except that polyvinyl chloride fibers were used as the raw fiber.

[0052] Example 3 Example 3 was the same as Example 1 except that the total tooth depth of the second gear portion was set to 3.0 mm.

[0053] Example 4 Example 4 was the same as Example 1, except that the total tooth depth of the first gear portion was set to 4.0 mm and the size of the second gear portion was set to 7.0 mm.

[0054] Comparative Example 1 In Example 1, the first gear portion was not used, and only the second gear portion was used. The total tooth depth of the second gear portion was set to 1.5 mm to form a crimped portion. This was used as Comparative Example 1.

[0055] Comparative Example 2 Comparative Example 2 was the same as Comparative Example 1 except that the total tooth depth of the second gear portion was set to 2.5 mm.

[0056] Comparative Example 3 Comparative Example 3 was the same as Comparative Example 1 except that the total tooth depth of the second gear portion was set to 3.0 mm.

[0057] Comparative Example 4 Comparative Example 4 was the same as Comparative Example 1 except that the total tooth depth of the second gear portion was set to 7.0 mm.

[0058] Comparative Example 5 Comparative Example 5 was prepared in the same manner as Comparative Example 2, except that polyvinyl chloride fibers were used as the raw fiber.

[0059] (Volume Increase Rate Measurement) As shown in FIG. 3 , the fiber bundles of Examples 1 to 4 and Comparative Examples 1 to 5 were cut to a length of 60 cm and a weight of 70 g, and the bulk was measured when laid flat on a horizontal surface. Similarly, the raw fiber bundles were cut to a length of 60 cm and a weight of 70 g, and the bulk was measured when laid flat on a horizontal surface. The ratio of the bulk of the fiber bundles of Examples 1 to 4 and Comparative Examples 1 to 5 to the bulk of the raw fiber bundle was then calculated as the volume increase rate (bulk). In other words, the volume increase rate (bulk) is the rate of change in bulk before and after crimping. Furthermore, as shown in FIG. 4 , the fiber bundles of Examples 1 to 4 and Comparative Examples 1 to 5 were braided, and the width and thickness were measured at a portion 10 cm from the tip. Similarly, each raw fiber bundle was braided, and the width and thickness were measured at a portion 10 cm from the tip. The ratio of the product of the width and thickness of each raw fiber bundle to the product of the width and thickness of each fiber bundle of Examples 1 to 4 and Comparative Examples 1 to 5 was calculated as the volume increase rate (braiding). In other words, the volume increase rate (braiding) is the rate of change in the cross-sectional area of ​​each raw fiber bundle and the fiber bundle of Examples 1 to 4 and Comparative Examples 1 to 5 when braided.

[0060] (FA Rate Measurement) A hair bundle volume measuring device (manufactured by BOSSA NOVA Vision, product name: BOLERO) was used to measure the flyaway rate (hereinafter also referred to as the FA rate) with a threshold value of 50%. Specifically, as shown in Figure 4, the fiber bundles of Examples 1 to 4 and Comparative Examples 1 to 5 were braided, and light was irradiated onto the portion up to 10 cm from the tip of the hair. Portions with transmittance less than 50% were classified as bulk, and portions with transmittance of 50% or more were classified as flyaways, and the proportion of flyaways to the total was measured.

[0061] (Method for observing the fiber side surface) <Sample preparation> In each of Examples 1 to 4 and Comparative Examples 1 to 5, a fiber (single yarn) was randomly extracted, cut to a natural length of 5 cm, and five pieces were attached to a mount at 5 mm intervals. <Photography> Observation and photography were carried out using a one-shot 3D shape measuring machine (manufactured by Keyence).

[0062] (Method for measuring degree of bending) The side photographs were imported into image analysis software (WinROOF, manufactured by Mitsubishi Corporation), and the bending path of the fiber (the length of the path tracing the fiber) of each of Examples 1 to 4 and Comparative Examples 1 to 5 was divided by the start-to-finish distance (5 cm), and the average value of five fibers was calculated as the degree of bending.

[0063] The measurement results for each of Examples 1 to 4 and Comparative Examples 1 to 5 are shown in Table 1.

[0064]

[0065] Comparing Example 1 and Comparative Example 1, as shown in Table 1, Example 1, in which crimping was performed twice in gear sections with different total tooth depth sizes, showed increased volume increase rate (bulk), volume increase rate (braided), and degree of bending, and a decreased FA rate, compared to Comparative Example 1, in which crimping was performed once. Furthermore, comparing Example 1 and Comparative Example 2, Example 2 and Comparative Example 5, Example 3 and Comparative Example 3, and Example 4 and Comparative Example 4, in which the tooth depth size of the second gear section is the same, Examples 1 to 4, in which crimping was performed in the first gear section, showed increased volume increase rate (bulk), volume increase rate (braided), and degree of bending, and a decreased FA rate, compared to Comparative Examples 2, 5, 3, and 4, in which crimping was not performed in the first gear section. These results demonstrate that the volume increase rate (bulk), volume increase rate (braided), and degree of bending increase, and the FA rate decrease, by crimping the first and second gear sections twice.

[0066] Comparing Example 1 and Example 2, which use different types of raw fiber, Example 1, which uses modacrylic fiber as the raw fiber, showed increased volume increase rate (bulk), volume increase rate (braid), and bending degree, while the FA rate was approximately the same. This shows that, from the perspective of volume, using modacrylic fiber as the raw fiber is superior to using PVC fiber.

[0067] In Examples 1, 3, and 4, which used modacrylic fiber as the raw fiber, the spacing between the peaks was narrower than the total tooth height of the second gear portion, and the peak height was smaller than in Comparative Examples 2 to 4, which used the same second gear portion. This is thought to be because the formation of small-crimp portions caused some of the small-crimp portions near the peaks to become entangled, shortening the distance between adjacent small-crimp portions. This tendency was also observed in Example 2 and Comparative Example 5, which used PVC fiber as the raw fiber, but was more pronounced in Examples 1, 3, and 4, which used modacrylic fiber as the raw fiber.

[0068] Comparing Examples 1, 3, and 4, it was found that the volume increase rate (bulk) increased as the total tooth depth of the second gear portion increased, suggesting that the volume increase rate (bulk) depended on the large crimped portion of the second gear portion.

[0069] On the other hand, the volume increase rate (braiding) and degree of bending were smaller in Example 4, where the total tooth depth size of the second gear portion was large and the difference between the first gear portion and the second gear portion was large, than in Examples 1 and 3, where the total tooth depth size of the second gear portion was small and the difference between the first gear portion and the second gear portion was small. Furthermore, when comparing Comparative Examples 1 to 4, the volume increase rate (braiding) decreased as the total tooth depth size of the second gear portion increased, and the volume increase rate (braiding) decreased significantly when the total tooth depth size of the second gear portion was between 2.5 mm and 3.0 mm. In other words, the trends were different between Examples 1 and 3 and Comparative Examples 2 and 3 when the total tooth depth size of the second gear portion was in the range of 2.5 mm to 3.0 mm. This suggests that the volume increase rate (braiding) depends on the small crimped portion caused by the first gear portion. Furthermore, from the viewpoint of increasing the volume when braiding, it was found that it is preferable that the size of the second gear portion be 3.0 mm or less and that the difference in total tooth height between the first gear portion and the second gear portion be less than 3.0 mm.

[0070] When comparing Comparative Examples 1 to 5, which were crimped once, no correlation was observed between the degree of bending and the FA rate, whereas when comparing Examples 1 to 4, which were crimped twice, it was found that as the degree of bending increased, the FA rate also decreased accordingly. This is thought to be because by crimping multiple times, many fibers were packed into the space, making the fibers more likely to entangle with each other, thereby suppressing the occurrence of fly-out hairs. In other words, this suggests the possibility that the FA rate can be controlled by controlling the degree of bending.

[0071] From the above results, it was found that by imparting double crimping using two types of gear sections with different total tooth depth sizes, the volume can be increased and the FA rate can be reduced. From the perspective of increasing volume, it was found that using modacrylic fiber as the raw fiber is superior to using PVC fiber. It was suggested that the volume increase rate (bulk) depends on the large crimped section created by the second gear section. It was suggested that the volume increase rate (braided) depends on the small crimped section created by the first gear section. When imparting double crimping, it was found that as the degree of bending increases, the FA rate also decreases.

[0072] REFERENCE SIGNS LIST 1 artificial hair 2 fiber bundle 5 raw fiber 10 large crimp section 11 small crimp section 15 first peak section 16 first valley section 17 second peak section 18 second valley section 30 manufacturing device 31 small crimp imparting section 32 large crimp imparting section 33 conveying roller section 35a, 35b first gear section 36a, 36b second gear section

Claims

1. The fiber bundle has a minimum pitch of 1 mm or more and is made up of a plurality of fibers each having large crimped portions in which first peaks and first valleys are alternately and repeatedly formed, The minimum amplitude of the large crimped portion is 0.30 mm or more and 4 mm or less, The large-crimped portion has a small-crimped portion in the vicinity of one first peak portion, the small-crimped portion having a pitch smaller than that of the large-crimped portion, The small-crimped portions are formed by alternately repeating second peaks and second valleys, The artificial hair, wherein the minimum amplitude of the small crimped portions is smaller than the minimum amplitude of the large crimped portions.

2. Artificial hair as described in claim 1, wherein the minimum pitch of the small crimped portion is 1.0 mm or more and 3.5 mm or less.

3. Artificial hair as described in claim 1 or 2, wherein the minimum amplitude of the small crimped portion is greater than 0 mm and less than 2 mm.

4. 3. The artificial hair according to claim 1, wherein the large crimped portions have a minimum pitch of 3.5 mm or less.

5. 3. The artificial hair according to claim 1, wherein the fiber bundle has a bending degree of 1.2 or more and 1.3 or less.

6. 3. The artificial hair according to claim 1, wherein the fiber bundle has an average fly-out rate of 23% or less in a portion 10 cm from the end of the hair when braided.

7. 3. The artificial hair according to claim 1, wherein the fibers are composed of at least one type of raw fiber selected from the group consisting of acrylic fibers, polyvinyl chloride fibers, polypropylene fibers, and polyethylene terephthalate fibers.

8. Artificial hair as described in Claim 7, wherein the fiber bundle is composed only of the one type of fiber.

9. The artificial hair according to claim 8, wherein the fiber bundles are made of modacrylic fibers.

10. The fiber bundle is a bundle of raw fiber to which the large crimped portion is added, 3. The artificial hair according to claim 1, wherein the bulk of said fiber bundle is 180% or more and 520% ​​or less of the bulk of a bundle of raw fiber of the same weight that does not form said large crimped portions.

11. a micro-crimping step of forming micro-crimps in which second peaks and second valleys are alternately and repeatedly formed on the raw fiber in a heated micro-crimping section to form a work fiber; a large-crimp imparting step of imparting large crimps to the in-process fiber in a heated large-crimp imparting section, in which first peaks and first valleys are alternately and repeatedly formed; The small crimp imparting section and the large crimp imparting section are both gear crimps, The small crimping unit has a pair of first gear units that are meshed with each other, The large crimp imparting unit has a pair of second gear units that mesh with each other, The large crimp-imparting portion has a total tooth depth of the second gear portion of 1 mm or more and is larger than a total tooth depth of the first gear portion, The small crimp imparting step is carried out before the large crimp imparting step, In the large-crimp imparting step, the hair is heated at a temperature lower than that in the small-crimp imparting step.

12. The method for producing artificial hair according to claim 11, wherein the difference in total tooth depth between the first gear part of the small crimp-imparting section and the second gear part of the large crimp-imparting section is 1 mm or more and 4 mm or less.

13. A method for manufacturing artificial hair as described in claim 11 or 12, wherein the first gear portion of the small crimping portion has a pitch of 1 mm or more and 4.0 mm or less.

14. A method for manufacturing artificial hair as described in claim 11 or 12, wherein the first gear portion of the small crimping portion has a total tooth height of 4.0 mm or less.

15. 13. The method for producing artificial hair according to claim 11 or 12, wherein the ratio of the volume when a predetermined weight of the raw fibers is braided to the volume when the same weight of the raw fibers is braided after the large crimp imparting step is 115% or more.