JP2012193485A - High strength spun machine sewing thread and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high performance machine sewing thread which is comprehensively superior to conventional filament machine sewing threads and spun machine sewing threads by improving the strength of a spun machine sewing thread which is inferior to a filament machine sewing thread.SOLUTION: A high strength spun machine sewing thread Y includes a composite twisted yarn having a mean fiber length of 300 to 600 mm, comprises stretch broken staple fibers of a synthetic fiber with substantially no crimp, and is obtained in such a manner that a bundle Y of the staple fibers is entangled and wound by a high pressure air injection and further subjected to a primary twisting in S direction, two or more of the primary twisted bundles Y are aligned and subjected to a secondary twisting in a Z direction, and an oil is attached thereon.

Description

  The present invention relates to a high strength span sewing thread excellent in strength and a method for producing the same. More particularly, the present invention relates to a high-strength spun sewing thread that is improved in strength and has excellent strength as well as sewing properties and a method for producing the same.

  In general, a span sewing thread has crimps and is obtained by spinning a short fiber having a fiber length of about 30 to 80 mm, and has a characteristic that the sewing performance is excellent but the strength is inferior to the filament sewing thread. In particular, when the elongation of a single fiber is lowered, its strength utilization rate is remarkably lowered, and improvement has been desired.

That is, the conventional span sewing thread has a large number of fluff on its side surface, and because of its effect, it can accompany a lot of air when traveling, so the friction between the sewing needle of the sewing needle and the sewing fabric compared to the filament sewing thread. The temperature rise due to can be kept low, and the high-speed sewing property is excellent.
In addition, the effect of the fluff is less likely to cause untwisting of the twist due to friction with the sewing needle and the sewing fabric, and is excellent in sewing properties.
On the other hand, since it consists of an aggregate of short fibers, the fiber arrangement is lower than that of filament sewing threads, and the strength utilization rate of single fibers is reduced, resulting in poor strength. In particular, a fiber having a low elongation of a single fiber has a drawback that the decrease in strength is extremely large as compared with a filament sewing thread, and therefore an improvement has been desired.

On the other hand, in order to improve these disadvantages, an improved sewing thread having the advantages of both a span sewing thread and a filament sewing thread has also been proposed.
A typical example is a so-called core yarn sewing thread (Patent Documents 1, 2, and 3), in which a filament yarn is used as a core and the periphery thereof is covered with crimped short fibers (Patent Documents 1, 2, and 3), or a filament yarn as a core. There is a sewing thread called a so-called spanned sewing thread in which the surroundings are entangled with a filament thread having a longer thread length (Patent Document 4).

  However, it is difficult to completely coat both the core yarn sewing thread and the spanned sewing thread in the coating process, or completely prevent the core thread and the covering fiber or the covering thread from slipping or peeling during the subsequent handling. When the core yarn is exposed due to coating spots, slips or peeling, the difference in physical properties between the core yarn and the coated fiber or the coated yarn, the difference in shrinkage during yarn dyeing, etc. are noticeable, and the influence of the morphological difference Thus, there are problems such as thread breakage, stitch skipping, puckering, and the like during sewing. Furthermore, these sewing yarns require fine yarns, and there is a problem that the cost is increased because productivity is lowered.

JP 2007-247077 A Japanese Patent Laid-Open No. 02-160943 JP-A-60-081348 Japanese Patent Laid-Open No. 06-128834

  An object of the present invention is to improve the strength of a span sewing thread which is inferior to a filament sewing thread, and to provide a high-performance sewing thread which is comprehensively superior to conventional filament sewing threads and span sewing threads.

The present invention comprises an average fiber length of 300 to 600 mm, a checkered short fiber bundle of synthetic fibers substantially free of crimps, and the short fiber bundle is entangled and wound by a high-pressure air jet stream, Furthermore, it is a high-strength span sewing yarn characterized by comprising a twisted yarn that is twisted in the S direction and aligned in the direction of 2 to 3 and twisted in the Z direction and to which an oil agent is attached.
Next, according to the present invention, a long fiber bundle of synthetic fibers having substantially no crimps is flattened into a flat yarn, and this is composed of two sets of nip rollers having different peripheral speeds, and a low-speed nip. A roller and a high-speed nip roller in this order, and the flat yarn is checked between the two sets of nip rollers, and then entangled and wound by a high-pressure air jet flow, and then an oil agent is applied. After winding up as a yarn of a check short fiber bundle having an average fiber length of 300 to 600 mm, the obtained yarn is further twisted in the S direction, and then two to three yarns are aligned and twisted in the Z direction. A method for producing the high-strength spun sewing yarn, characterized in that a twisted yarn is obtained.

  According to the present invention, it is possible to obtain a high-strength spun sewing thread that improves the strength problem and is excellent not only in sewing but also in strength.

It is the schematic which shows an example of the apparatus for implementing this invention. It is the schematic diagram which showed an example of the side surface of the check short fiber bundle before performing S twist and Z twist obtained by the apparatus of FIG.

  First, a method for producing a high-strength spun sewing thread according to the present invention will be described. A long fiber bundle of synthetic fibers having substantially no crimps is flattened into flat yarns, which have different peripheral speeds. Two sets of nip rollers are passed through a low-speed nip roller and a high-speed nip roller in this order, and the flat yarn is checked between the two sets of nip rollers, and then entangled by a high-pressure air jet flow. After spinning, the oil agent was applied and wound as a yarn of a check short fiber bundle having an average fiber length of 300 to 600 mm, and then the obtained yarn was further twisted in the S direction, It is obtained by aligning three and twisting in the Z direction to obtain a twisted yarn.

As a material constituting the synthetic fiber used in the high-strength spun sewing thread of the present invention, polyesters such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polytritylene terephthalate, aliphatic polyamides such as nylon 6 and nylon 66, Polyolefins such as polyparaphenylenebenzobisoxazole, polyacrylate, polyethylene, and polypropylene can be exemplified. Polyethylene terephthalate, polyethylene naphthalate, and polyacrylate are preferable.
The total fineness of the fiber bundle of the synthetic fiber is preferably 70 to 4,000 dtex, more preferably 100 to 3,000 dtex, and the single fiber fineness is preferably 0.5 to 5.0 dtex, more preferably 0.8 to 3.0 dtex.
The number of filaments in the long fiber bundle of synthetic fibers is about 20 to 300, preferably 40 to 250.

In order to facilitate checkability, the synthetic fiber long fiber bundle is preferably one in which the fiber bundle is less crimped, twisted, or entangled, and the fiber oil agent has less convergence, friction and static electricity.
In other words, if there is crimp, the fiber tends to stretch and contract easily, and the nip of the fiber end by the check roller becomes uncertain, and if there is a place where twisting, entanglement or convergence or friction due to oil is strong, stress concentrates there, and static electricity When this occurs, the fiber during check is disturbed, and in any case, it becomes a cause of check spots, which is not preferable.

  In addition, when supplying a long fiber bundle to a check device described later, for example, if the long fiber bundle is wound around a bobbin or the like, the bobbin is rotated while rotating the bobbin so that twisting does not occur during unwinding. Even after unwinding and feeding, the long fiber bundle may be rubbed against the side surface of the bobbin at the time of unwinding, and the S / Z may be twisted alternately. Thus, it is necessary to devise such as canceling the S / Z twist by taking an extension space of one traverse or more when winding the bobbin.

  In the present invention, a long fiber bundle of synthetic fibers is flattened (tape-shaped) into flat yarns, which are formed of two sets of nip rollers having different peripheral speeds, a low-speed nip roller and a high-speed nip roller. In this case, the nip roller is held so that the flat state is maintained in any nip roller, and the flat yarn is checked between the two sets of nip rollers. It is entangled by a high-pressure air jet.

That is, a pair of low-speed nips in the thickness direction of the flatness is set so that the long fiber bundle of synthetic fibers that are flattened and the fibers are arranged in parallel is made flat (tape-like) and the flat state is maintained. By gripping with a roller, a fiber bundle is obtained in which the fibers are mixed in pieces without causing the fibers to form a large lump.
In addition, even with a high-speed nip roller, the flat yarn made of long fibers fed from the low-speed nip roller is gripped in the thickness direction of the flat so as to maintain the flat state, and between the nip rollers, Check the flat yarn. At this time, in correspondence with the peripheral speed ratio of the high-speed nip roller and the low-speed nip roller, the fibril lump of fibers remaining in the flat yarn is reduced.
Furthermore, the flat yarn fed from the low-speed nip roller is held and checked one by one in the order of arrival at the high-speed nip roller, so that a mixed fiber state in which the fibers are mixed at the level of single fibers is obtained. It is done.
In this invention, after the said process, the fiber bundle sent out from a high-speed nip roller is passed through an air injection nozzle, and the individual fiber is wound by a high-pressure air injection flow.

Further, the fiber bundle obtained in this way is gripped by another pair of high-pressure nip rollers whose peripheral speed is 10 to 30 times faster than that of the high-pressure nip roller, and is then shredded and further reduced to about 10 to 30 times. Stretched.
In addition, since the mixed fiber bundle is fiber-gripped one by one in the order of arrival at the high-pressure nip roller on the high-speed side, it is further finely dispersed, and a mixed fiber state of single fiber order is obtained.
Furthermore, since the thin fiber bundle sent out from the high-pressure side high-pressure nip roller is entangled and wound by the high-pressure air jet nozzle, each fiber is disturbed, and more A finely dispersed mixed fiber state is obtained.

  The entangled and wound short fiber bundle is provided with an oil agent for a normal sewing thread such as a silicone system, and then wound once, and then subjected to S twisting on the yarn comprising the short fiber bundle. After that, the high-strength span sewing yarn of the present invention can be obtained by aligning 2 to 3 of these and applying an upper twist in the Z direction.

Next, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic view showing an example of an apparatus for carrying out the present invention.
That is, in FIG. 1, the synthetic fiber long fiber bundle A is passed through the opening guide G1 to bend and flattened while being bent, and the opened flat yarn is moved to the low-speed nip roller R1 and the peripheral speed thereof. The nip roller R2 is passed through a fast high-speed nip roller R2. At that time, the flat nip is held between both nip rollers in a thickness direction so that the flat state is maintained. Checking the yarn, then sucking the checked fiber bundle using the air injection nozzle N1 between the nip roller R2 and the nip roller R3, and further winding the fiber bundle using the air injection nozzle N2, The oiling agent for the sewing thread is applied by the oiling device O and wound around the winder W as a check short fiber bundle Y. Examples of the oil agent for the sewing thread include a silicone oil agent, a mineral oil agent, and a paraffin oil agent. Moreover, the adhesion amount of an oil agent is 0.2 to 3.0 weight% normally with respect to a check short fiber bundle, Preferably it is about 0.5 to 2.0 weight%.

In order to facilitate checking between the nip roller R1 and the nip roller R2, it is preferable that the yarn supplied to the nip roller R1 is not twisted or entangled as described above. In addition, a fiber oil agent may be applied to the yarn, but an oil agent that has little convergence and friction and hardly generates static electricity is preferable. That is, twisting, entanglement, static electricity, fiber oil agent convergence, friction, and the like are not preferable because check spots are likely to occur.
Further, as the fiber opening guide G1, a known cylindrical or spindle-shaped rod-shaped guide with a swelled central portion arranged in parallel, or a guide in which several rod-shaped guides are bent in an arc shape are used. it can. As the opening guide, ceramic, metal or the like can be arbitrarily adopted.
In addition, if the guide G2 for slightly reducing the width of the opened flat yarn at the portion immediately before the nip roller R1 behind the opening guide is provided, the fiber density at the end of the flat yarn increases. The fiber wrapping around the nip roller R1 can be prevented, which is preferable.
Further, the yarn path guides such as the fiber opening guide G1 and the guide G2 may be twisted when applied obliquely in the length direction of the long fiber bundle, and therefore, care must be taken so that the yarn guides hit perpendicularly.

The ratio of the peripheral speed of the nip roller R1 to the peripheral speed of the nip roller R2 is preferably 1: 8 to 1:40, and more preferably 1:10 to 1:30. That is, when the ratio of the peripheral speeds is less than 1: 8, it is necessary to increase the peripheral speed of the nip roller R1, so that the fiber end after the checkout is easily wound around the ratio. The thickness ratio of the check yarn due to spots increases, which is not preferable.
Moreover, it is preferable to provide the guide G3 which interrupts | blocks the accompanying flow of the air which generate | occur | produces on this roller surface in the nip roller R2 flow toward a roller edge part direction at a nip point. In other words, unless this accompanying flow is interrupted, the tip of the fiber sent out from the nip roller R1 tends to be difficult to stably nip with the nip roller R2, and therefore a check spot is likely to occur, Absent.

Further, as the air injection nozzle N1, a nozzle having a suction action is used so that the check fiber carried out from the nip roller R2 does not stick to the roller, but has a turning action simultaneously with the suction action. Use of a nozzle is preferable because fibers can be sucked more effectively.
On the other hand, as the air injection nozzle N2, depending on the purpose, the short fiber bundle that has been checked is wound around the short fiber end by a swirling flow, or the fibers in the short fiber bundle are disturbed and entangled. Can be used. In addition, as the air injection nozzle N2, since the obtained check short fiber bundle is subjected to S twisted twisting, the winding direction of the end of the short fiber when entangled and wound by the air injection flow Are mainly in the S twist direction.

By the manufacturing method described above, a check short fiber bundle in which spanned single fibers are mixed and entangled and wound as shown in FIG. 2 is obtained.
The average fiber length of the synthetic fibers after check in the short fiber bundle thus obtained is 300 mm to 800 mm, preferably 350 to 600 mm. If it is less than 300 mm, sufficient strength cannot be obtained when it is made into a sewing thread. On the other hand, if it exceeds 800 mm, the fibers are hardly entangled and cannot be sufficiently strong.
In order to set the average fiber length of the synthetic fibers in the fiber bundle within the above range, the ratio of the peripheral speed of the nip roller R1 to the peripheral speed of the nip roller R2 may be 1: 8 to 1:40.

The yarn comprising the checkered short fiber bundles thus obtained is subjected to, for example, 100 to 800 turns / m of the lower twist in the S direction, and further 2 to 3 of these are twisted to 150 to 800. Twist / m in the Z direction is twisted to obtain a twisted yarn, and the high-strength spun sewing yarn of the present invention is obtained. If the final twist direction is the Z direction, the sewing performance is improved, which is preferable.
The total fineness of the high-strength spun sewing thread after twisting according to the present invention is usually about 70 to 4,000 dtex, preferably about 100 to 3,000 dtex.

Hereinafter, the present invention will be described more specifically with reference to examples.
[Example 1]
Using the production apparatus shown in FIG. 1, using a polyethylene terephthalate fiber (Tetoron Fiber Co., Ltd., Tetoron) with a total fineness of 420 dtex and a fiber count of 48 as the long fiber bundle A of synthetic fibers, no twisting occurs during unwinding As the bobbin is rotated, it is unwound in the direction of the outer periphery of the bobbin, and it is passed through the opening guide G1 with a 2.3m extension space to reduce twisting and entanglement. Further, these were overlapped in the thickness direction, and the spread width was regulated to about 7 mm width using the guide G2, and supplied to the high pressure nip roller R1.
Next, the fiber bundle is uniformly checked and thinly drawn between the high-pressure nip roller R1 and the high-pressure nip roller R2 whose peripheral speed is 20 times faster than this, and subsequently sucked between the high-pressure nip roller R2 and the nip roller R3. Conjugation is imparted to the composite fiber bundle using the air injection nozzle N1 and the conjugation air injection nozzle N2 utilizing a swirling flow, and the fiber bundle is formed into a substantially untwisted fiber bundle of 280 dtex as shown in FIG. Was wound around a winder W as a sewing thread Y having a side surface shape in which the ends of the yarn were wound and bound and conjugated. A length of 50 cm was withdrawn from the wound sewing thread Y, split into short fibers, and the short fiber length was measured. As a result, the average value was 380 mm. The number of n is about 10, and the following measurement of the short fiber length is the same.
The sewing yarn Y was subjected to a lower twist of 500 times / m in the S direction, and two of them were further twisted in the Z direction of 400 times / m to obtain a double-thread span sewing thread. The obtained sewing thread was a sewing thread with sufficient strength and good high-speed sewing. The results are shown in Table 1.

[Comparative Example 1]
Using the manufacturing apparatus shown in FIG. 1, a long fiber bundle of synthetic fibers similar to that in Example 1 is uniformly distributed between the high-pressure nip roller R1 and the high-speed nip roller R2 between the nip rollers R2 40 times faster. The average short fiber length of the sewing thread obtained in the same manner as in Example 1 except that it was checked and narrowed was 250 mm. The double-sewing machine thread obtained in the same manner as in Example 1 had low strength and poor high-speed stitchability. The results are shown in Table 1.

[Example 2]
As a long fiber bundle A of synthetic fiber, a polyethylene terephthalate fiber (Tetoron fiber, Tetoron) having a total fineness of 560 dtex and a filament number of 96 f is used as a high-pressure nip roller R1 and this fiber bundle. A uniform dampening was performed between the high-pressure nip rollers R2 whose peripheral speed was 15 times faster, and a narrow draft was obtained to obtain a 330 dtex sewing thread. As a result of measuring the short fiber length, the average value was 550 mm.
The sewing yarn Y was subjected to 400 twists / m in the S direction under twisting, and two of them were combined, and 450 times / m in the Z direction top twisting was performed to form a twin yarn span sewing thread. The obtained sewing thread was sufficiently strong and had high sewing speed and good sewing thread. The results are shown in Table 1.

Example 3
As a long fiber bundle A of synthetic fiber, a polyethylene terephthalate fiber (Tetron Co., Ltd., Tetoron) having a total fineness of 560 dtex and a filament number of 48 f is used, and the fiber bundle is used as a high-pressure nip roller R1 and from this. A high-pressure nip roller R2 having a peripheral speed 25 times faster was uniformly checked and narrowly drawn to obtain a 330 dtex sewing thread. As a result of measuring the short fiber length, the average value was 430 mm.
This sewing thread Y was subjected to 400 twists / m in the S direction under twist, and three of these were combined to give 450 turns / m in the Z direction top twist to form a twin yarn span sewing thread. The obtained sewing thread had sufficient strength and high sewing speed and was good. The results are shown in Table 1.

[Comparative Example 2]
As the long fiber bundle A of synthetic fiber, polyethylene terephthalate fiber (Tetron Fiber Co., Ltd., Tetoron) having a total fineness of 420 dtex and a filament number of 48 f is used, and the fiber bundle is used as a high-pressure nip roller R1 and The machine was uniformly checked between the high-pressure nip rollers R2 whose peripheral speed was 12 times faster than this, and was drawn finely to obtain a 300 dtex sewing thread. As a result of measuring the short fiber length, the average value was 700 mm.
The sewing yarn Y was subjected to 400 twists / m in the S direction under twisting, and two of them were combined, and 450 times / m in the Z direction top twisting was performed to form a twin yarn span sewing thread. The obtained sewing thread had insufficient binding and binding of the short fiber bundles that had been checked, and the appearance of the seam was very poor. The results are shown in Table 1.

[Comparative Example 3]
As a long fiber bundle A of synthetic fibers, polyethylene terephthalate fiber (Tetron, manufactured by Teijin Fibers Ltd.) having a total fineness of 560 dtex and a filament number of 96 f is used, and the fiber bundle is used as a high-pressure nip roller R1 and A 300 dtex sewing thread was obtained by uniformly checking and thinly drawing between the high-pressure nip rollers R2 whose peripheral speed was 35 times faster than this. As a result of measuring the short fiber length, the average value was 150 mm.
The sewing thread Y was subjected to a lower twist of 500 times / m in the S direction, and two of them were combined to be subjected to an upper twist of 450 times / m in the Z direction to obtain a double-thread span sewing thread. The obtained sewing thread had low strength and poor high-speed stitchability. The results are shown in Table 1.

Example 4
As a long fiber bundle A of synthetic fiber, polyethylene naphthalate fiber (Teonex, manufactured by Teijin Fibers Ltd.) having a total fineness of 560 dtex and a filament number of 48 f is used, and the fiber bundle is used as a high-pressure nip roller R1. In addition, it was uniformly checked between the high-pressure nip rollers R2 whose peripheral speed was 18 times faster than this, and was drawn finely to obtain a 420 dtex sewing thread. As a result of measuring the short fiber length, the average value was 500 mm.
The sewing yarn Y was subjected to 400 twists / m in the S direction under twisting, and two of them were combined, and 450 times / m in the Z direction top twisting was performed to form a twin yarn span sewing thread. The obtained sewing thread was a sewing thread having sufficient strength and good high-speed stitchability. The results are shown in Table 1.

Example 5
The synthetic fiber long fiber bundle A is a polyacrylate fiber (Kuraray Co., Ltd., Vectran) having a total fineness of 560 dtex and a filament number of 48 f. The production apparatus shown in FIG. A high-pressure nip roller R2 having a peripheral speed 18 times faster was uniformly checked and thinly drawn to obtain a 380 dtex sewing thread. As a result of measuring the short fiber length, the average value was 600 mm.
The sewing yarn Y was subjected to a lower twist of 550 times / m in the S direction, and two of them were further subjected to an upper twist of 480 times / m in the Z direction to obtain a twin spun sewing yarn. The obtained sewing thread had sufficient strength and good high-speed stitchability. The results are shown in Table 1.

The strength of the sewing thread shown in Table 1 is a value measured in accordance with JISL1095.9.5.1 at a gripping interval of 20 cm and a tensile speed of 20 cm / min.
Also. The sewing machine thread has high-speed sewing capability when the sewing needle # 20 is used to sew 4 T / R surges at a sewing speed of 4,000 rpm and the sewing thread is frequently cut. It showed in.
The puckering is indicated as "Good" when there is no puckering (sewing shrinkage that can be made at the time of sewing) when one T / C broad is sewed with the sewing needle # 20, and "X" when there is no puckering.
For the appearance of the seam, observe the sewing cloth sewn under the same conditions as the high-speed sewing, and if it is good (when there is no stitch skipping or thread breakage), it is ○, if it is defective (1 or more stitch skipping, thread) The case where cuts occurred) is indicated by x.

  According to the high-strength span sewing thread according to the present invention, it can be used as a sewing thread that has sufficiently high-speed stitchability and strength, and has a good seam appearance.

A: long fiber bundle of synthetic fiber G1: opening guide G2: flat yarn width adjustment guide G3: air wake blocking guide R1: low speed nip roller R2: high speed nip roller R3: nip roller N1, N2: air injection nozzle O: Oiling device W: Winder Y: Checked short fiber bundle (sewing thread)

Claims (6)

  The average fiber length is 300 to 600 mm, which is composed of checkered short fibers of a synthetic fiber substantially free of crimps, and the short fiber bundle is entangled and wound by a high-pressure air jet, and further down in the S direction. A high-strength spun sewing thread characterized by comprising a twisted yarn that is twisted and twisted in two to three, twisted in the Z direction, and attached with an oil agent.   The high-strength span sewing thread according to claim 1, wherein the winding direction of the short fiber ends when wound by the air jet flow is mainly the S twist direction.   The high-strength spun sewing thread according to claim 1 or 2, wherein the synthetic fiber is selected from polyethylene terephthalate fiber, polyethylene naphthalate fiber, and polyacrylate fiber.   A long fiber bundle of synthetic fibers that does not substantially have crimps is flattened into flat yarns, which are divided into two sets of nip rollers having different peripheral speeds, a low-speed nip roller and a high-speed nip roller. After passing in order and checking the flat yarn between the two sets of nip rollers, and then entangled and wound by a high-pressure air jet flow, an oil agent is applied and the average fiber length is 300 to 600 mm. After winding as a yarn of the checkered short fiber bundle, further twist the obtained yarn in the S direction, then draw two or three pieces together and twist them in the Z direction to make a twisted yarn. The method for producing a high strength span sewing thread according to claim 1.   The method for producing a high-strength span sewing thread according to claim 4, wherein the winding direction of the short fiber ends when wound by the air jet flow is mainly the S twist direction.   The method for producing a high-strength spun sewing thread according to claim 4 or 5, wherein the synthetic fiber is selected from polyethylene terephthalate fiber, polyethylene naphthalate fiber, and polyacrylate fiber.