Patent Application
20240373964
The present invention relates to artificial hair and a method for manufacturing artificial hair.
Conventionally, a fiber bundle for artificial hair resembling human hair has been used as a material of a head decoration product such as a hairpiece, a wig, an extension, a braid, or a hair band (for example, Patent Document 1).
For example, in the fiber bundle for artificial hair of Patent Document 1, a resin fiber is crimped by gear crimp to give volume to a hair top and to imitate human hair.
In order to impart a large volume to a braid, it is preferable to provide a large crimp, but on the other hand, if the large crimp is provided, a pitch becomes too wide to provide a fiber bundle close to straight hair. Therefore, there is a problem that the braid stop of the fiber becomes worse when forming the braid or the like.
Therefore, an object of the present invention is to provide artificial hair and a method for manufacturing artificial hair, which are capable of achieving both a good volume when braided and good braid stop of a hair tip as compared with the conventional case.
One aspect of the present invention for solving the above problems is artificial hair including a fiber bundle including a large crimp part having a minimum pitch of 1 mm or more and 7 mm or less, wherein the large crimp part includes a small crimp part having a pitch smaller than that of the large crimp part near one peak part.
The term “pitch” as used herein refers to a distance between adjacent peak parts or a distance between adjacent valley parts. The same applies hereinafter.
The term “near” as used herein refers to a range within ¼ of the minimum pitch of the large crimp part.
According to this aspect, the small crimp part is provided near the peak part of the large crimp part, and thus the small crimp parts are easily entangled with each other, a volume when braided is easily maintained, and the braid stop of a hair tip is good.
One aspect of the present invention is artificial hair including a fiber bundle including a large crimp part having alternatively formed first peak parts and first valley parts with a minimum pitch of 1 mm or more, wherein a minimum amplitude of the large crimp part is 0.30 mm or more and 4 mm or less, wherein the large crimp part includes a small crimp part having a pitch smaller than that of the large crimp part near one peak part, wherein the small crimp part has alternatively formed second peak parts and second valley parts, wherein a minimum amplitude of the small crimp part is smaller than the minimum amplitude of the large crimp part.
In a preferable aspect, the small crimp part has a minimum pitch of 1.0 mm or more and 3.5 mm or less.
In a preferable aspect, the small crimp part has a minimum amplitude of more than 0 mm and 2 mm or less.
In a preferable aspect, the large crimp part has a minimum pitch of 3 mm or less.
In a preferable aspect, the fiber bundle has a flexion degree of 1.2 or more and 1.3 or less.
The “flexion degree” as used herein refers to the ratio of the total length of a fiber based on crimp to the length of the fiber in an extending direction as a whole, ignoring crimp. That is, the “flexion degree” refers to the ratio of a natural length to a maximum length when the fiber is extended.
In a preferable aspect, the fiber bundle has an average flyaway hair rate of 23% or less at a portion of 10 cm from a hair tip when formed into a braid.
The term “flyaway hair” as used herein refers to a state where a short fiber springs out from the surface of the fiber bundle as illustrated in
That is, the “flyaway hair rate” is an index indicating how much the flyaway hair of the fiber bundle is present when formed into the braid, and refers to the ratio of the flyaway hair to the whole when the fiber bundle is classified into a bulk in which the ratio of transmitted light when irradiated with light is less than 50% and flyaway hair in which the ratio of transmitted light when irradiated with light is 50% or more.
In a preferable aspect, the fiber bundle is composed of at least one raw material fiber selected from the group consisting of an acrylic fiber, a polyvinyl chloride fiber, a polypropylene fiber, and a polyethylene terephthalate fiber.
In a preferable aspect, the fiber bundle consists only of the one raw material fiber.
In a more preferable aspect, the fiber bundle is composed of a modacrylic fiber.
In a preferable aspect, a bulk of the fiber bundle is 180% or more and 520% or less with respect to a bulk of the raw material fiber bundle of the same weight.
One aspect of the present invention is a method for manufacturing artificial hair including: a small crimp applying step of applying a small crimp part with a small crimp applying part obtained by heating a raw material fiber to form an in-progress fiber; and a large crimp applying step of applying a large crimp part to the in-progress fiber with a heated large crimp applying part, wherein in the large crimp applying step, heating is performed at a temperature lower than that in the small crimp applying step.
According to this aspect, it is possible to form a large crimp part maintaining the small crimp part, and it is possible to manufacture artificial hair which is capable of achieving both a good volume when braided and good braid stop of a hair tip as compared with the conventional case.
In a preferable aspect, the small crimp applying step is performed before the large crimp applying step.
One aspect of the present invention is a method for manufacturing artificial hair including: a small crimp applying step of applying a small crimp part having alternatively formed second peak parts and second valley parts with a small crimp applying part obtained by heating a raw material fiber to form an in-progress fiber; and a large crimp applying step of applying a large crimp part having alternatively formed first peak parts and first valley parts to the in-progress fiber with a heated large crimp applying part, wherein the small crimp applying part and the large crimp applying part are both gear crimps, wherein the small crimp applying part includes a pair of first gear parts engaged with each other, wherein the large crimp applying part includes a pair of second gear parts engaged with each other, wherein a total tooth length of the second gear parts in the large crimp applying part is 1 mm or more and larger than a total tooth length of the first gear parts, wherein the small crimp applying step is performed before the large crimp applying step, and wherein in the large crimp applying step, heating is performed at a temperature lower than that in the small crimp applying step.
In a preferable aspect, a difference between the total tooth length of the first gear parts of the small crimp applying part and the total tooth length of the second gear parts of the large crimp applying part is 1 mm or more and 4 mm or less.
In a preferable aspect, a pitch of the first gear parts of the small crimp applying part is 1 mm or more and 4.0 mm or less.
In a preferable aspect, the total tooth length of the first gear parts of the small crimp applying part is 4.0 mm or less.
In a preferable aspect, the small crimp applying part and the large crimp applying part are both gear crimps, and a difference in total tooth length is 1 mm or more.
The term “total tooth length” as used herein refers to a distance from a tooth bottom to a tooth tip.
In a preferable aspect, the small crimp applying part and the large crimp applying part are both gear crimps, the total tooth length of the gear of the large crimp applying part is 3.0 mm or less, and a difference in the total tooth length between the gears of the small crimp applying part and the large crimp applying part is less than 3.0 mm.
In a preferable aspect, a ratio of a volume when the fiber after the large crimp applying step, which has the same weight as a predetermined weight of the raw material fiber, is braided to a volume when the raw material fiber having the predetermined weight is braided is 115% or more.
The present invention can achieve both a good volume when braided and good braid stop of a hair tip as compared with the conventional case.
Hereinafter, embodiments of the present invention will be described in detail.
Artificial hair 1 according to a first embodiment of the present invention is artificial hair for braid, and is suitably used mainly for braiding.
As shown in
The fiber bundle 2 extends in a predetermined bundle shape, and includes a large crimp part 10 having an amplitude in a direction intersecting a longitudinal direction and extending in a wave shape in the longitudinal direction.
In the large crimp part 10, a first peak part 15 and a first valley part 16 are regularly and repeatedly formed as shown in
The minimum pitch of the large crimp part 10 (a distance D1 between the adjacent first peak parts 15 and 15 or a distance D2 between the adjacent first valley parts 16 and 16) is preferably 3 mm or more, more preferably 3.5 mm or more. And the minimum pitch of the large crimp part 10 may be 1 mm or more, or may be or may be 1.75 mm or more.
The minimum pitch of the large crimp part 10 is preferably 13.5 mm or less, and more preferably 11 mm or less.
And the minimum pitch of the large crimp part 10 may be 7 mm or less, or may be 3.5 mm or less, or may be 3 mm or less, or may be 2.5 mm or less.
The minimum amplitude of the large crimp part 10 (a length L1 from the bottom of the first valley part 16 to the vertex of the first peak part 15) is preferably 0.8 mm or more, and more preferably 1.2 mm or more.
And the minimum amplitude of the large crimp part 10 may be 0.30 mm or more, or may be 0.38 mm or more.
The minimum amplitude of the large crimp part 10 (a length L1 from the bottom of the first valley part 16 to the vertex of the first peak part 15) is preferably less than 7 mm, more preferably 6 mm or less, still more preferably 5 mm or less.
And the minimum amplitude of the large crimp part 10 may be 4 mm or less, or may be 2 mm or less, or may be 1.40 mm or less, or may be 0.49 mm or less.
The large crimp part 10 includes a small crimp part 11 over the entire longitudinal direction.
The small crimp part 11 is a crimp provided over the entire large crimp part 10, and as shown in
In the small crimp part 11, a second peak part 17 and a second valley part 18 are repeatedly formed substantially regularly.
The minimum pitch of the small crimp part 11 (a distance D3 between the adjacent second peak parts 17 and 17 or a distance D4 between the adjacent second valley parts 18 and 18) is preferably smaller than the minimum pitch of the large crimp part 10.
The minimum pitch of the small crimp part 11 (a distance D3 between the adjacent second peak parts 17 and 17 or a distance D4 between the adjacent second valley parts 18 and 18) is preferably 1.0 mm or more, more preferably 1.5 mm or more.
The minimum pitch of the small crimp part 11 is preferably 7 mm or less, more preferably 3.5 mm or less, still more preferably 3 mm or less, and particularly preferably 2.5 mm or less.
The minimum amplitude of the small crimp part 11 (a length L2 from the bottom of the second valley part 18 to the vertex of the second peak part 17) is preferably smaller than the minimum amplitude of the large crimp part 10.
The minimum amplitude of the small crimp part 11 (a length L2 from the bottom of the second valley part 18 to the vertex of the second peak part 17) is preferably more than 0 mm, preferably 0.30 mm or more, and more preferably 0.38 mm or more.
The minimum amplitude of the small crimp part 11 is preferably 0.6 mm or more, and more preferably 0.7 mm or more.
The minimum amplitude of the small crimp part 11 is preferably less than 7 mm, more preferably 4 mm or less, still more preferably 3 mm or less.
And the minimum amplitude of the small crimp part 11 may be 2 mm or less, or may be 1.40 mm or less, or may be 0.49 mm or less.
In the fiber bundle 2, the fiber 5 is preferably composed of at least one raw material fiber selected from the group consisting of an acrylic fiber, a polyvinyl chloride fiber, a polypropylene fiber, and a polyethylene terephthalate fiber, and more preferably composed of a modacrylic fiber.
The cross-sectional shape of the fiber 5 is not particularly limited, and may be, for example, a circular shape, a Y shape, an H shape, a U shape, a C shape, an X shape, or a flat shape or the like.
Next, a manufacturing machine 30 suitable for manufacturing the artificial hair 1 of the present embodiment will be described.
The manufacturing machine 30 is a crimp forming device that forms the crimp parts 10 and 11 in the raw material fiber to form the fiber bundle 2, and includes a small crimp applying part 31, a large crimp applying part 32, and a conveyance roller part 33 as shown in
The small crimp applying part 31 is a gear crimp, and includes a pair of first gear parts 35a and 35b engaged with each other.
The first gear parts 35a and 35b preferably have a pitch S1 of 1.0 mm or more, and more preferably 2 mm or more. The first gear parts 35a and 35b preferably have a pitch S1 of 8 mm or less, and more preferably 5 mm or less, and still more preferably 4.0 mm or less.
In the first gear parts 35a and 35b, a total tooth length T1 is preferably more than 0 mm, and more preferably 1.0 mm or more.
In the first gear parts 35a and 35b, the total tooth length T1 is preferably less than 7 mm, more preferably 6 mm or less, still preferably 4.0 mm or less, still more preferably less than 3.0 mm, and particularly preferably 2 mm or less.
The large crimp applying part 32 is a gear crimp, and includes a pair of second gear parts 36a and 36b engaged with each other.
The second gear parts 36a and 36b are gears whose total tooth length T2 is larger than the total tooth length T1 of the first gear parts 35a and 35b.
In the second gear parts 36a and 36b, a pitch S2 is preferably 1 mm or more, more preferably 1.5 mm or more, and still more preferably 1.75 mm or more, and still more preferably 2.0 mm or more.
In the second gear parts 36a and 36b, the pitch S2 is preferably 10 mm or less, and more preferably 8 mm or less, and still more preferably 7.0 mm or less, and still more preferably 3 mm or less. In the second gear parts 36a and 36b, the pitch S2 may be 2.5 mm or less.
In the second gear parts 36a and 36b, a total tooth length T2 is preferably 1 mm or more and 7 mm or less, and more preferably 6 mm or less, and still more preferably 5 mm or less, and still more preferably 4 mm or less.
The difference between the total tooth length T2 of the second gear parts 36a and 36b and the total tooth length T1 of the first gear parts 35a and 35b is preferably 1 mm or more and 4 mm or less, more preferably 2.5 mm or less, and still more preferably 1.5 mm or less.
The conveyance roller part 33 is a section for conveying the raw material fiber between the large crimp applying part 32 and the small crimp applying part 31 at a predetermined speed.
Next, a method for manufacturing the artificial hair 1 recommended when the artificial hair 1 of the present embodiment is manufactured by the manufacturing machine 30 will be described.
First, a bundle of raw material fibers (hereinafter, also referred to as a raw material fiber bundle) is passed through the heated small crimp applying part 31 by the conveyance roller part 33 to apply the small crimp part 11, thereby forming an in-progress fiber bundle (small crimp applying step).
At this time, a heating temperature (the temperature of the first gear parts 35a, 35b) in the small crimp applying part 31 is preferably 95° C. or higher and 100° C. or lower.
A passage speed in the small crimp applying part 31 is preferably 0.5 m/min. or more and 8.0 m/min. or less.
The in-progress fiber bundle is passed through the heated large crimp applying part 32 by the conveyance roller part 33 to apply the large crimp part 10, thereby forming the fiber bundle 2 (large crimp applying step).
At this time, in the large crimp applying step, the in-progress fiber bundle is heated at a temperature lower than that in the small crimp applying step. That is, the heating temperature (the temperature of the second gear parts 36a, 36b) in the large crimp applying part 32 is lower than the heating temperature (the temperature of the first gear parts 35a, 35b) in the small crimp applying part 31, and is preferably 80° C. or higher and 90° C. or lower from the viewpoint of maintaining the shape of the small crimp part 11.
A passage speed in the large crimp applying part 32 is preferably 0.5 m/min. or more and 8.0 m/min. or less.
The passage speed in the small crimp applying part 31 and the passage speed in the large crimp applying part 32 may be the same or different.
Next, the physical properties of the artificial hair 1 of the present embodiment will be described.
In the artificial hair 1, the ratio (flexion degree) of the length of the fiber bundle 2 to the length of the raw material 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, the product of a width and a thickness at a portion 10 cm from the tip when the fiber bundle 2 is braided is preferably 65% or more, more preferably 115% or more, and still more preferably 117% or more, with respect to the product of a width and a thickness when the raw material fiber bundle is braided.
In the artificial hair 1, the product of the width and the thickness at a portion 10 cm from the tip when the fiber bundle 2 is braided is preferably 200% or less, and more preferably 170% or less, and still more preferably 150% or less, and particularly preferably 148% or less, with respect to the product of the width and the thickness when the raw material fiber bundle is braided.
In the artificial hair 1, the bulk of the fiber bundle 2 is preferably 180% or more, more preferably 200% or more, and still more preferably 250% or more, with respect to the bulk of the raw material fiber bundle of the same weight.
In the artificial hair 1, the bulk of the fiber bundle 2 is preferably 520% or less, more preferably 500% or less, and still more preferably 425% or less, with respect to the bulk of the raw material fiber bundle of the same weight.
In the artificial hair 1, as shown in
The arithmetic average flyaway hair rate can be, for example, an arithmetic average value of 10 times when measured 10 times.
According to the artificial hair 1 of the present embodiment, the small crimp parts 11 and 11 adjacent to each other are close to each other near one first peak part 15 of the large crimp part 10, and thus the small crimp parts 11 and 11 are easily entangled with each other, the volume of the braid is easily maintained, and the braid stop of the hair top is good.
According to the method for manufacturing the artificial hair 1 of the present embodiment, the large crimp applying step is performed after the small crimp applying step, and in the large crimp applying step, the in-progress fibers are heated at a temperature lower than that of the small crimp applying step, so that both a good volume of the braid and good braid stop of the hair tip can be achieved.
In the embodiment described above, the small crimp applying part 31 includes the pair of first gear parts 35a and 35b, but the present invention is not limited thereto. The small crimp applying part 31 may include a plurality of pairs of first gear parts 35a and 35b.
Similarly, in the above-described embodiment, the large crimp applying part 32 includes the pair of second gear parts 36a and 36b, but the present invention is not limited thereto. The large crimp applying part 32 may include a plurality of pairs of second gear parts 36a and 36b.
In the embodiment described above, the two types of crimp applying parts 31 and 32 having different sizes of the gear part form the two types of large and small crimp parts 10 and 11, but the present invention is not limited thereto. Three or more types of crimp parts may be formed by three or more types of crimp applying parts 31 and 32 having different sizes of the gear part.
In the embodiment described above, the plurality of raw material fibers are bundled to form a raw material fiber bundle, the raw material fiber bundle is passed through the crimp applying parts 31 and 32, and the crimp parts 10 and 11 are applied to the raw material fiber bundle, but the present invention is not limited thereto. The raw material fibers may be passed through the crimp applying parts 31 and 32 one by one without being bundled, and the crimp parts 10 and 11 may be applied to the raw material fibers to form the fiber bundle 2.
In the embodiment described above, the crimp parts 10 and 11 are formed over the entire longitudinal direction of the fiber bundle 2, but the present invention is not limited thereto. The crimp parts 10 and 11 may be formed only in a part of the fiber bundle 2 in the longitudinal direction.
In the above embodiment, the small crimp part 11 is formed over the entire large crimp part 10, but the present invention is not limited thereto. The small crimp part 11 may be formed only in a part of the large crimp part 10.
In the embodiments described above, the component members can be freely replaced or added between the embodiments as long as it is included in the technical scope of the present invention.
Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.
Modacrylic fibers were used as raw material fibers, and a raw material fiber bundle obtained by bundling the raw material fibers was passed through a first gear part having a total tooth length size of 1.5 mm under conditions of a set temperature of 140° C., a gear temperature of 95° C. to 100° C., and a passage speed of 0.5 m/min to 8.0 m/min with a constant pressure. Thereafter, the resultant was passed through a second gear part having a total tooth length size of 2.5 mm under the conditions of a set temperature of 120° C., a gear temperature of 80° C. to 90° C., and a passage speed of 0.5 m/min to 8.0 m/min with a constant pressure to form a large crimp part and a small crimp part. The fiber bundle thus obtained was used as Example 1.
A fiber bundle obtained in the same manner as in Example 1 except that polyvinyl chloride fibers were used as raw material fibers was used as Example 2.
A fiber bundle obtained in the same manner as in Example 1 except that the total tooth length size of a second gear part was 3.0 mm was used as Example 3.
A fiber bundle obtained in the same manner as in Example 1 except that the total tooth length size of a first gear part was 4.0 mm and the size of a second gear part was 7.0 mm was used as Example 4.
A fiber bundle obtained in the same manner as in Example 1 except that the size of a second gear part was 7.0 mm was used as Example 5.
A fiber bundle obtained in the same manner as in Example 1 except that the total tooth length size of a first gear part was 2.5 mm and the size of a second gear part was 4.0 mm was used as Example 6.
In Example 1, a first gear part was not used, only a second gear part was used, and the total tooth length size of the second gear part was 1.5 mm to form a crimp part. This was used as Comparative Example 1.
A fiber bundle obtained in the same manner as in Comparative Example 1 except that the total tooth length size of a second gear part was 2.5 mm was used as Comparative Example 2.
A fiber bundle obtained in the same manner as in Comparative Example 1 except that the total tooth length size of a second gear part was 3.0 mm was used as Comparative Example 3.
A fiber bundle obtained in the same manner as in Comparative Example 1 except that the total tooth length size of a second gear part was 7.0 mm was used as Comparative Example 4.
A fiber bundle obtained in the same manner as in Comparative Example 2 except that polyvinyl chloride fibers were used as raw material fibers was used as Comparative Example 5.
As shown in
The ratio of the bulk of the fiber bundle of each of Examples 1 to 4 and Comparative Examples 1 to 5 to the bulk of each of the raw material fiber bundles was calculated as a volume increase rate (bulk).
That is, the volume increase rate (bulk) is the change rate of the bulk before and after crimp applying.
As shown in
The ratio of the product of the width and the thickness of the fiber bundle of each of Examples 1 to 4 and Comparative Examples 1 to 5 to the product of the width and the thickness of each of the raw material fiber bundles was calculated as the volume increase rate (braid).
That is, the volume increase rate (braid) is the cross-sectional area change rate when braided, from each of the raw material fiber bundles to the fiber bundle of each of Examples 1 to 4 and Comparative Examples 1 to 5.
A hair bundle volume measuring device (manufactured by BOSSA NOVA Vision, product name: BOLERO) was used to measure a flyaway hair rate (hereinafter, also referred to as FA rate) using a threshold of 50%. Specifically, as shown in
In each of Examples 1 to 4 and Comparative Examples 1 to 5, fibers (single yarns) were arbitrarily extracted, and cut so that the natural length was 5 cm, and five fibers were attached to a mount at 5 mm intervals.
Observation and photographing were performed with a one-shot 3D shape measuring machine (manufactured by KEYENCE CORPORATION).
Image analysis software (WinROOF, manufactured by Mitani Shoji Co., Ltd.) captured side photographs taken, and calculated a value as a flexion degree by dividing a fiber flexion path (length of a path tracing the fiber) of each of Examples 1 to 6 and Comparative Examples 1 to 5 by a start-end distance (5 cm), and an average value of 5 fibers was obtained.
The measurement results in each of Examples 1 to 4 and Comparative Examples 1 to 5 are shown in Table 1.
When Example 1 and Comparative Example 1 were compared, as shown in Table 1, in Example 1 in which crimps were applied twice to gear parts having different total tooth length sizes, the volume increase rate (bulk), the volume increase rate (braid), and the flexion degree increased and the FA rate decreased as compared with Comparative Example 1 in which a crimp was applied once.
When Example 1 and Comparative Example 2, Example 2 and Comparative Example 5, Example 3 and Comparative Example 3, and Example 4,5 and Comparative Example 4, having a common tooth length size of the second gear part, were compared respectively, in Examples 1 to 5 in which crimps were applied in the first gear part, the volume increase rate (bulk), the volume increase rate (braid), and the flexion degree increased and the FA rate decreased as compared with Comparative Examples 2, 5, 3, and 4 in which crimps were not applied in the first gear part.
From these results, it was found that the volume increase rate (bulk), the volume increase rate (braid), and the flexion degree increased and the FA rate decreased by applying crimps twice by the first gear part and the second gear part.
When Example 1 and Example 2 in which the types of the raw material fibers were different were compared, in Example 1 in which the modacrylic fibers were used as the raw material fibers, the volume increase rate (bulk), the volume increase rate (braid), and the flexion degree increased, and the FA rate was about the same.
From this, it was found that from the viewpoint of volume, the use of modacrylic fibers is superior to the use of PVC fibers as raw material fibers.
In Examples 1, 3, and 4 in which the modacrylic fibers were used as the raw material fibers, the interval between the peak parts (the interval without distinguishing the first peak and the second peak) was narrower than the total tooth length of the second gear part, and the height of the peak part was smaller than that in each of Comparative Examples 2 to 4 in which the same second gear part was used.
This is considered to be because, due to the formation of the small crimp parts, some of the small crimp parts near the peak parts are entangled with each other, and the distance between adjacent small crimp parts is shortened.
This tendency was the same in the relationship between Example 2 and Comparative Example 5 in which PVC fibers were used as raw material fibers, but Examples 1, 3, and 4 in which modacrylic fibers were used as raw material fibers were more remarkable.
Comparison among Examples 1, 3, and 5 showed that the volume increase rate (braid) increases as the total tooth length size of the second gear part increases.
From this, it was suggested that in the case that the small crimp part is equally crimped by the first gear parts, the volume increase rate (braid) depends on the large crimp part by the size of the second peak part of the second gear part.
Meanwhile, in regard to the volume increase rate (bulk), comparison among Examples 1, 3, and 5 showed that the volume increase rate (bulk) varies forming the shape of an arch with a peak at which the total tooth length size of the second gear part is 3.0 mm. From this, it was suggested that the volume increase rate (bulk) has a maximum point in the range from 2.5 mm to 7.0 mm of the total tooth length size of the second gear part.
In regard to the flexion degree, comparison among Examples 1, 3, and 5 showed that the flexion degree is constant regardless of the total tooth length size of the second gear part, and comparison among Examples 4, 5, and 6 showed that the larger the total tooth length size of the first gear part is, the smaller the flexion degree is. From this, it was suggested that the flexion degree depends on the size of the second peak parts of the small crimp part by the first gear parts.
In comparison with Examples 3 and 6, in which the difference of the total tooth length sizes of the first gear part and the second gear part is equal, the volume increase rate (braid) is almost constant regardless of the size difference of the first gear part and the second gear part in Examples 3 and 6. From this, it was suggested that the difference of the total tooth length sizes of the first gear part and the second gear part influences the volume increase rate (braid).
In comparison with Comparative Examples 1 to 4, the volume increase rate (braid) decreased with an increase in the total tooth length size of the second gear part, and the volume increase rate (braid) significantly decreased when the total tooth length size of the second gear part was 2.5 mm to 3.0 mm.
That is, the tendency was different between Examples 1, 3, 5 in which, as mentioned above, as the total tooth length size of the second gear part increased, the volume increase rate (braid) increased, in contrast, and Comparative Examples 1 to 4 in which as the total tooth length size of the second gear part was increased, the volume increase rate (braid) decreased.
From this, it was suggested that the tendency of the volume increase rate (braid) was reversed under the influence of the existence of the small crimp part by the first gear part.
From the viewpoint of increasing the volume when braided, it was found that the size of the first gear part is preferably 4.0 mm or less, and more preferably 1.5 mm or more and 2.5 mm or less.
Comparison of Comparative Examples 1 to 5 in which crimps were applied once showed no correlation between the flexion degree and the FA rate, whereas comparison of Examples 1, and 3-6 in which crimps were applied twice showed that, in the range from 3.0 mm or more to 7.0 mm or less of the total tooth length size of the second gear part, as the total tooth length size of the second gear part was decreased, the FA rate also coordinately decreased.
This is considered that when many fibers are packed in the space by applying crimps a plurality of times, because the fibers are easily entangled with each other by decreasing the total tooth length size of the second gear part, the generation of the flyaway hair is suppressed. That is, the possibility that the FA rate can be controlled by controlling the total tooth length size of the second gear part was suggested.
From the above results, it was found that the volume can increase and the FA rate can decrease by applying crimps twice with two types of gear parts having different total tooth length sizes.
From the viewpoint of increasing the volume, it was found that the use of modacrylic fibers is superior to the use of PVC fibers as raw material fibers.
It was suggested that the volume increase rate (bulk) almost depends on the size of the large crimp part by the second gear part and has a maximum point in the range from 2.5 mm to 7.0 mm.
It was suggested that when the size of the small crimp part by the first gear part is constant, the volume increase rate (braid) depends on the size of the large crimp part by the second gear part.
In the case of applying crimps twice, it was found that the FA rate can be controlled by controlling the total tooth length size of the second gear part.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022-008035 | Jan 2022 | JP | national |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2022/044895 | Dec 2022 | WO |
| Child | 18777971 | US |
