JPS5947739B2 - Manufacturing method of fused alternately twisted yarn - Google Patents

Description

[Detailed description of the invention] A0 Technical field of the present invention The present invention relates to a method for producing fused alternately twisted yarn.

More specifically, it relates to a method of false twisting thermoplastic fiber multifilament yarn to produce a special alternately twisted yarn that can effectively form a fabric that exhibits a strongly twisted yarn-like texture and a light Kasuri pattern. S-twisted yarn portions and Z-twisted yarn portions alternate in the axial direction, and the yarn portion in one of the twisting directions is a relatively long, tightly twisted yarn structure, and the yarn portion in the other twisting direction is a bulky twisted yarn. The present invention relates to a method for producing a special alternately twisted yarn structure.

Machi: Prior Art and its Problems There are many techniques known in the art that alternately form untwisted yarn portions and twisted yarn portions by false twisting.

For example, an example where polyester-based drawn fibers or polyamide-based drawn fibers are false-twisted using a spindle-type false-twisting device at extremely high heating temperatures that cause the fibers to fuse together. However, the Special Public Interest Publication No. 50-25065
No. Publication, Special Publication No. 51-225, Special Publication No. 51-42
It is described in Publication No. 662, etc.

Examples of false twisting of drawn fibers under high retraction supply using a false twisting device that applies fluid swirl flow are disclosed in JP-A-51-143746 and JP-A-51-1999. 14
It is described in Japanese Patent Publication No. 3749, Japanese Patent Publication No. 53-15188, Japanese Patent Publication No. 30818-1984, etc.

In addition, there are techniques that apply an active unsteady action to the yarn that is being subjected to the false twisting process.

For example, as a technique for varying the contact state between the yarn and the heating device, Japanese Patent Laid-Open Nos. 49-66928 and 51-Sho.
15017, Japanese Patent Application Laid-Open No. 52-8119, etc., and Japanese Patent Publication No. 51-34016 and Japanese Patent Application Laid-open No. 49-554 as a technique for varying the twist propagating from the false twisting device toward the heating device. , JP-A-50-121546, etc., and as a technique for varying the number of twists of yarn generated by a false twisting device, JP-A-49-8414, JP-A-49-108353, and JP-A-49-108353 are disclosed. Showa 53-61
745, etc., and Japanese Patent Application Laid-Open No. 49-92337 as a technique for varying the speed of yarn passing through a false twisting device.
JP-A-49-92354, etc., as a technique to make the yarn to be false-twisted non-uniform in the length direction.
JP-A-52-66722, JP-A-53-8174
No. 9, Japanese Patent Application Laid-Open No. 101654/1984, etc.

All of the above conventional techniques form alternately twisted yarns by false twisting, but in addition to clear S-twisted yarn portions and Z-twisted yarn portions, they also form a large amount of untwisted yarn portions similar to normal false-twisted yarns. , by forming a relatively long untwisted yarn part between the S-twisted yarn part and the Z-twisted yarn part, or by forming the twist density in the untwisted yarn part or the untwisted yarn part to be high in the center and low at both ends. If the twist density of the untwisted yarn portion or each twisted yarn portion is not constant, or if the length fraction of the untwisted yarn portion of the entire system cannot be formed high, the average twist density of the entire system may be It has a defect that cannot be increased.

Alternatively, it may have a twist in the false-twisting heating direction, or it may be untwisted to the extent that the false-twist crimp is exposed, and it may be formed as an untwisted yarn portion that has lost its tightness. untwisted yarn portions, such as fibers that are fused to each other or untwisted without exposing the false twist crimp, and are formed as untwisted yarn portions that have lost bulk. It had a defect in that it was not possible to clearly form a difference in form between the twisted yarn part and the twisted yarn part.

Although many attempts have been made to improve the deficiencies of the prior art, they are still incomplete.

This is because previous research has mainly focused on optimizing external factors for forming alternately twisted yarns, such as false twisting conditions such as the number of false twists, processing tension, and heating temperature, physical properties of processed yarn, and structure of false twisting equipment. This is thought to be due to the fact that the alternating twist yarn formation mechanism itself was hardly paid attention to.

Object of the present invention The alternately twisted yarn obtained according to the present invention aims to obtain a preferable strong twist yarn-like effect in the alternately twisted yarn structure consisting of untwisted portions and untwisted portions, and to interact with the untwisted portions. The aim is to find a favorable effect of Kasuri on the difference in form from the over-twisted part.

In other words, the object of the present invention is to provide a method for producing a special alternately twisted yarn that exhibits an excellent strong twist-like texture and a light splashed pattern, and can also exhibit a well-made light splashed pattern.

A further particular object of the present invention is to prevent the S and Z twists from remaining in the fabric, especially when the alternately twisted yarn is used as the warp of a fabric, since the S and Z twists cancel each other out due to beating. In fact, if each S-twisted yarn part or Z-twisted yarn part is long, the proportion of these twists remaining will increase, and it is extremely effective in creating the above-mentioned excellent strong-twisted yarn-like texture and pale Kasuri pattern.
The present invention provides a method for manufacturing a special alternately twisted yarn that can form the twisted yarn portion and the Z twisted yarn portion to be relatively long, the length of each of these portions can also be formed randomly, and can exhibit the well-made light Kasuri pattern. It's about getting.

26 Structure of the present invention In order to achieve the above object, the present invention has the following configuration.

"When drawing and false twisting a thermoplastic undrawn fiber multifilament yarn, a device arranged in the order of an upstream twist supply device, a heated splicing plate, a second splicing plate, a false twisting device, and a yarn take-off device is used. The stretching ratio set by the yarn supply device and the yarn take-off device is set to be less than or equal to the natural stretching ratio of the undrawn yarn, and the temperature of the heated splicing plate is set so that the yarn is fused to form an untwisted part. , and the temperature is such that a part of the constituent filaments peels off in the untwisting region, and the second grafting plate controls the yarn path by contacting the yarns to prevent false twist ballooning, and also cools the yarns to prevent false twist ballooning. The twisting device uses a circumscribed friction false twisting device to maintain the fusion of the yarns even immediately after passing through the false twisting device, and to reduce the distance from the yarn passing through the friction false twisting device to the first member it comes into contact with by 200 mm. A method for producing a fused alternately twisted yarn, characterized in that a part of the untwisted yarn is destroyed in an untwisted region between the false twisting device and the contact member to form a continuously twisted yarn portion.

In the present invention, it is first necessary to use an undrawn yarn as a starting yarn and to draw it at a magnification equal to or lower than the natural stretching ratio.

The reason for this is that when the thermoplastic filament fiber is drawn at a natural draw ratio or less, it is easy to cause fusion even at a relatively low temperature, and the thread tension can be lowered.

When the thread tension is low, the fused portion is difficult to break.

Further, in the above, undrawn yarn refers to conventional undrawn yarn spun at low speed, highly oriented undrawn yarn spun at high speed, and the like.

Next, the temperature of the heated yarn bonding plate (false twisting temperature) needs to be at the fusion temperature of the yarn and at a temperature that causes the constituent filaments of the yarn to separate in the untwisting region.

More specifically, it refers to a temperature below the melting point of the yarn, at which each constituent filament fuses together while maintaining its fiber shape.

When such a false twisting temperature is adopted, when a multifilament yarn whose fibers are fused together under heating is subjected to a large deformation called untwisting, the twisted yarn structure cannot be subjected to large deformation strain, and the fiber structure is The insufficiently fused portion, that is, the fused portion, peels off.

Next, in the present invention, the second grafting plate has a yarn path regulating function that can prevent false twist ballooning.

The reason for this is that in simultaneous stretching and false twisting, the tension is higher than in simple false twisting, and ballooning is more likely to occur.

The second grafting plate capable of regulating the yarn path is, for example, a metal plate having a radius of curvature, and allows the yarn to run in contact with the outer curved surface of the metal plate.

Further, the second grafting plate needs to have a function of cooling the yarn fused in the previous step.

The reason for this is that in the present invention, in particular, long fused portions are formed in the yarns, so in the heat bonding plate, for example,
Compared to No. 124519, it provides relatively strong heating,
In order to form a relatively strong fusion bond, forced cooling is particularly required for the second bonding plate.

Here, cooling is sufficient if the temperature is below the secondary transition point of the yarn as commonly used by those skilled in the art.

If the second bonding plate is not provided, if the fused yarn is passed through the false twisting device in a fused state, the yarn will almost return to a non-twisted state, which is preferable (0).

Next, in the present invention, is it necessary to use a circumscribed friction false twister?

This is to give a feeding effect to the yarn, reduce passing resistance, lower processing tension, prevent ballooning, and perform false twisting in a substantially stationary state.

Next, in the present invention, it is necessary to maintain the above-mentioned fused state even immediately after passing through the false twisting device.

This is to form a relatively long untwisted fused portion and give it a strongly twisted appearance and feel.

Next, in the present invention, it is necessary that the distance between the false twisting device and the first contact member be 200 mm or more.

This is to make the untwisted and fused portions longer to emphasize the highly twisted appearance and texture.

In addition, the ballooning prevention means prevents ballooning in the untwisted region between the false twisting device and the first contact member and maintains a stationary state, thereby destroying a portion of the untwisted and fused portion to form a threaded twisted yarn portion. I can do it.

The first contact member may be any member as long as it can prevent the yarn from rotating in the untwisting region, such as a yarn pulling device such as a nip roller, or a rotating device with a yarn bending contact angle of 30° or more. It may also be a roller or the like.

E1 Functions and Effects of the Present Invention According to the findings of the present inventors, the formation of alternately twisted yarns during false twisting is caused by the false twisting device and upstream thereof; As mentioned above, there are many prior art technologies that actively generate this phenomenon, and the formation of the alternately twisted yarn itself is performed downstream of the false twisting device.

In the prior art, when observing the yarn immediately downstream of the false twisting device, there are various cases such as when an untwisted yarn portion is formed, when a threaded yarn portion is formed, and when a non-twisted yarn portion is formed. situation occurs.

The formation of the untwisted yarn portion is also diverse, and can be roughly divided into cases where the untwisted yarn portion that is being formed rotates in the false twist direction commensurate with its twist density, and cases where the untwisted yarn portion that is forming rotates less than that. In the latter case, the number of twists upstream of the false twisting device is reduced.

Further, the formation of the threaded yarn portion is accompanied by an increase in the number of twists upstream of the false twisting device.

Further, the untwisted yarn portion may be formed as a transient phenomenon between the untwisted yarn portion and the twisted yarn portion, or may be formed clearly continuously.

On the other hand, when observing the area slightly downstream from the immediate downstream of the false twisting device, no new untwisted yarn portion is formed in this area.

The untwisted yarn portion is formed when an untwisted yarn portion that involves rotation of the yarn is formed immediately downstream of the false twisting device, and the downstream end portion of the untwisted yarn portion is untwisted and formed sequentially. If an untwisted yarn portion exists downstream of the untwisted yarn portion, the untwisted yarn portion may be heated and formed.

The untwisted yarn portion may be formed by the twists of the untwisted yarn portion and the twisted yarn portion offsetting each other.

In the prior art, as described above, there are various formations of alternately twisted yarns, resulting in the above-mentioned defects.

On the other hand, in the present invention, we have found that it is most effective to form an untwisted yarn portion that involves rotation of the yarn immediately downstream of the false twisting device, which is sometimes observed in the above-mentioned conventional technology. This has succeeded in continuing the formation almost all the time, and furthermore, the untwisted yarn portion, which involves rotation, is brought into a state almost equivalent to the so-called false-twisting heating state upstream of the false-twisting device.

Looking at it from another perspective, the state in which the false-twisting heating region extends to the downstream of the false-twisting device is maintained at all times.

In this way, the tip of the false-twisting heating area located downstream of the false-twisting device rotates, and the rotation also damages the rear end of the previously formed untwisted yarn and its own tip. The tip of the false-twist heating area moves in the downstream direction while sequentially forming untwisted and threaded yarn portions.

The rotation of the tip of this false-twisting heating area eventually stops when it is gripped by a take-up roller, comes into contact with a guide, etc., or the rotational force applied by the false-twisting device cannot be transmitted.

Even if the rotation of the tip of the false-twisting heating area stops, the false-twisting device continues to apply rotational force, so in the next moment a new untwisting point is created between the tip of the false-twisting heating area and the false-twisting device. occurs, and that point becomes the tip of a new false twist heating region, and the above phenomenon is repeated, resulting in an alternately twisted yarn in which unheated yarn portions and twisted yarn portions are alternately formed.

A non-twisted yarn portion is practically not formed under such an alternate twist yarn forming machine groove.

In the present invention, as described above, the alternating yarn forming mechanism is such that even after the yarn passes through the false twisting device, at least the vicinity of the false twisting device is always kept in a false twist heating state, and the yarn is The present invention is characterized in that a part of the twisted yarn that is always open is present between the false twisting device and the member that first comes into bending contact after passing through the false twisting device.

A more detailed explanation will be given below with reference to one drawing.

FIG. 1 shows step 1 of the method for producing fused alternately twisted yarn of the present invention.
1 is a process schematic diagram showing an example, 1 is a feeding device, 2 is a heating bonding plate, 3 is a friction false twisting device, 4 is a first take-up device, 5 is a second
6 is a heating device, 6 is a second take-off device, and 7 is an alternately twisted yarn.

A second suction plate (not shown) is provided between the heating suction plate 2 and the frictional false twisting device 3.

Needless to say, the second heating device 5 and the second take-off device 6 can be used as needed, and are not essential.

8 is a rotating member that rotates as the yarn runs and/or a fixing member that the yarn rubs against, which is provided as necessary at an appropriate position between the false twisting device 3 and the first take-up device 4. It is a member.

This member 8 itself is preferably supported fixedly to the machine base.

Since the false twisting device 3 applies rotational force to the yarn, it also attempts to rotate the yarn downstream of the false twisting device (rotation in the direction of false twist heating); It is possible to continue the false-twist heating state by rotating the false-twist without untying it.

This false-twist heated state (untwisted) is subject to the action of untwisting as appropriate, but when the untwisted yarn portion is untwisted, the twist density of the entire untwisted yarn portion gradually decreases. A portion of the untwisted yarn is untwisted without decreasing, and the twist density itself of the untwisted yarn portion does not substantially change and gradually becomes shorter, and the untwisted yarn portion absorbs a large amount of twist and becomes an untwisted yarn portion. It is better to untwist the yarn so that it gradually becomes longer, and the present invention takes advantage of this.

In order to produce such untwisting, the untwisted yarn portion should have high cohesiveness and high torsional rigidity, and once untwisted, it should lose cohesiveness and have low torsional rigidity.

For example, it is necessary to provide an appropriate degree of fusion, that is, to provide a degree of fusion that allows a portion of the fusion in the untwisted state to be separated by the untwisted region.

The heating temperature should be selected in consideration of the physical properties of the yarn material and the physical properties and amount of surface deposits such as oil.

Under such a mechanism, as mentioned above, the tip of the false-twisting heating area located downstream of the false-twisting device rotates, and the rotation is applied to the rear end of the previously formed untwisted yarn and the self-twisting region. The tip of the false-twisting heating area moves in the downstream direction while untwisting the tip and sequentially forming the untwisted portion.

The rotation of the tip of this false-twisting heating area will eventually stop and become unstable due to being gripped by a take-up roller, coming into contact with a guide, etc., or being unable to transmit the rotational force applied by the false-twisting device. Even if the rotation of the tip of the false-twisting heating area stops in this way, the false-twisting device continues to apply rotational force, so that at the next moment, the rotation between the tip of the false-twisting heating area and the false-twisting device A new untwisting point occurs, and this point becomes the tip of a new false-twisting heating region, and the above phenomenon is repeated, resulting in a parent intertwisted yarn in which untwisted yarn portions and twisted yarn portions are alternately formed.

In other words, in any case, the downstream side (take-up side) of the tip point of the false-twisting heating area where the rotation of the tip has stopped is the twisted yarn part, but in the present invention, in particular, such false-twisting The rotation of the tip of the heating zone is stopped by a mechanism in which the rotational force applied by the false twisting device is no longer fully transmitted. The bending contact member is provided in such a way that a threaded yarn portion is always present between the member that initially makes nip or bending contact after the twisting process and the false twisting device.

Here, the continuous twisted yarn portion that is always present is 1
It is preferable to set the number to about 2.3 to 2.3.

FIGS. 2, 3, and 4 show the formation mechanism of alternately twisted yarns in this manner at the time [.

This is a schematic diagram showing the transition from tl to t2 over time. In the figure, T is the false twisting point, G is the bending contact point, P is the boundary between the untwisted yarn part and the threaded yarn part, and Q is the untwisted yarn part. This is the twisting point.

In FIGS. 2, 3, and 4, time t.

Assuming that the tip P of the false-twisting heating region reaches the uncertain position A at (take-up side) is the untwisted yarn part, the upstream side of Pl is in the false twisting heating area, so it is in an untwisted state, and point P cannot rotate now, so there is an untwisted part between point T and point P1. Untwisting begins at one definite point Q1.

Thereafter, point 212 point Q1 advances downstream at the yarn speed.

The untwisted yarn portion becomes an untwisted state, the torque is balanced, and both ends of the untwisted yarn portion are connected to P2. Let's call it P3.

The part between 21 and 22 goes downstream as an untwisted yarn part and becomes 22 to 2.
The length of the third part is the twisted thread part, which increases in length and moves downstream.

Point P1 moves downstream as the tip of the new false twisting heating area, and finally reaches an uncertain position where it is no longer possible to transmit the rotational force applied by the false twisting device downstream again. (in each figure, the state is at time t2), and then at time t.

A state similar to that occurs, and a new untwisting point Q2 (uncertain) is formed, and the same phenomenon as that of the card is repeated.

To explain each of Fig. 1, Fig. 3, and Fig. 4 in more detail, Fig. 2 shows the case where untwisting occurs only at point P3, and the untwisted yarn portions P2 to P3 are long toward the upstream direction. In addition, in Fig. 3, untwisting occurs preferentially at the initial point P2, and the untwisted yarn portions P2 to P3 increase in length toward the downstream direction. Is it the one that moves downstream in the same way?
After that, untwisting cannot occur at point P2, but untwisting occurs at point P3 (that is, untwisting increases in length toward the upstream direction), and FIG. 4 shows 1. , 12, as the time progresses, the untwisting advances downstream or upstream from Ql, or alternately advances downstream and upstream, and the length of the untwisted yarn portions P2 to P3 is changed in both the up and downstream directions. The tip P3 of the new false-twisting heating area is formed as it increases toward the downstream.

In addition, it is conceivable that untwisting occurs only in P2 from the time Q1 is formed until the time Q2 is formed.

In the actual processing process, various thread formation phenomena such as these occur almost randomly.

As is clear from each figure, the continuous twisted yarn portion existing between the TGs is at time t.

At time t2, there is one piece, and at time [1, there are two pieces.

In any case, in the present invention, an untwisted yarn portion is always present between the TGs.

The member with which the yarn forming point G in FIGS. 2 to 4 comes into bending contact for the first time after passing through the false twisting device may be the first take-off device 4 itself in FIG. may be provided with such a bending contact member.

When providing a special bending contact member, a rotating member that rotates as the thread runs, a fixed member that the thread rubs against, etc. are preferably used, and these may be used alone or in an appropriate combination.

When using a fixing member against which the thread rubs, the angle θ of bending contact with the fixing member (Fig. 1) should be such that the total bending contact angle is 30
It is preferable to set it to less than 100 °C; if it is larger than this, the passing resistance of the running yarn becomes large, which is undesirable.

As is clear from Figures 2 to 4, the position of the bending contact member, that is, the position of point G, is set at a position that can be reached by the tip point of the false twisting heating area (in other words, the mechanism is such that the twisted yarn portion does not exist momentarily). In this case, the length of the untwisted yarn portion to be formed is regulated, and at the same time, the length of the untwisted yarn portion is also regulated, so long S-twisted yarn portions and Z-twisted yarn portions are formed. This is not desirable at all because it becomes impossible to do so.

A specific embodiment of the yarn obtained by the present invention utilizes false twisting, so it is a multi-filament yarn consisting of long fibers with false twist crimps, and has a Z-twisted yarn portion (or an S-twisted yarn portion). is a tightly twisted yarn part where the fiber crimping form matches the twisted structure of the yarn, and the S-twisted yarn part (or Z-twisted yarn part) is a bulky twisted yarn part where the crimped form of the fibers is exposed. S.

Whether the part of Z is a tightly twisted yarn part or a bulky twisted yarn part can be set by appropriately selecting the false twist heating direction.

Each S-twisted yarn portion and Z-twisted yarn portion can be formed to be relatively long, and each of the 49 points shown in FIGS. 2 to 4 and especially Q3. Since the untwisting point of Q2 is at a random position between the TGs (however, Ql and Q2 are random between A and T, and between the opening and T), their respective lengths also have large variations. It can be obtained as something worth having.

When carrying out the present invention, it can be achieved by paying attention to and observing the above-mentioned phenomena and selecting the false twisting mode and false twisting conditions (particularly the installation position of the bending contact member, etc.).

Listing the findings obtained in the present invention, the following aspects and conditions seem to be preferable.

(1) The twist density of the untwisted yarn portion remains almost the same as the twist density of the false twist heating, so it is preferable to have a higher number of false twists, but if the number of false twists is too high, two types of twist will occur and false twisting will occur. The number of twists passing through the twisting device fluctuates, or the heating force of the false twisting device approaches or exceeds the gripping force limit and heating becomes intermittent, which may cause the formation of untwisted yarn portions.

As a guideline, it is preferable that the number of false twists is slightly lower than that of normal false twist crimp processing.

(2) Vibration of the yarn during processing, especially ballooning near the false twisting device, is undesirable as it may cause fragmentation of the untwisted yarn portion or loss of stability in processing, so ballooning should be caused as much as possible. It is preferable that the ballooning be at such a level that it cannot be recognized with the naked eye.

(3) If the yarn tension downstream of the false twisting device is high, the twists of the untwisted yarn portion and the twisted yarn portion may cancel each other out, or a high twist density may not enter the twisted yarn portion, or the false twisting device It is undesirable that the fibers are untwisted at the same time as they pass through.

Therefore, it is preferable to weaken the yarn tension as much as possible, and consideration must be given to the method, structure, processing conditions, etc. so as to reduce the passing resistance of the false twisting device and guides.

(4) If a strong abrasion action or large deformation of curvature is applied to the false twisting device or upstream thereof, the above (3)
In addition to the matters similar to the above, the fused bond may peel off or the twisted structure may be destroyed while the material is heated, resulting in a decrease in cohesiveness, and the material is often untwisted as soon as it passes through the false twisting device. I don't like it at all.

Consideration must be given to the method, structure, processing conditions, etc. of the false twisting device and guides to avoid strong abrasion or large curvature deformation.

Although the present invention is not limited to the above-mentioned items, when false-twisting thermoplastic fiber multifilament yarn, if the process is preferably carried out in accordance with the above-mentioned items, the yarn passes through a false-twisting device. Even after the yarn passes through the false-twisting device, the false-twisting device can be constantly kept in a heating state at least in the vicinity of the false-twisting device, and the false-twisting device can By installing the bending contact member so that an over-twisted yarn portion always exists between them, an alternately twisted yarn can be formed according to the yarn forming mechanism as described above, and the special alternately twisted yarn that achieves the intended purpose of the present invention can be created. This is something you can get from being a big brother.

Note that the earlier patent application 1982-12, which is the basic invention of the present invention,
Compared to Publication No. 4519, in the present invention, a second grafting plate having a cooling function is provided, and the distance between the false twisting device and the first contact member is set to 200 mm or more, so that the ununtwisted and fused portion can be made longer. did it.

Hereinafter, the specific configuration and effects of the present invention will be explained using Examples.

Example 1 Melt-spinning polyethylene telescrate to 3000
A multifilament yarn with a thickness of 137 denier and 36 filaments was produced by drawing at a speed of m/min.

While this yarn was stretched 1.4 times, false twisting was performed in the stretching region at a heating temperature of 237°C and a number of false twists of 3200 T/m.

The heating device was a suction plate with a length of 1.5 m and a radius of curvature of 30 m, with a semicircular groove having a radius of 2 mm, and the false twisting device was a triaxial circumscribed friction false twisting device.

The distance between the heating device and the false twisting device was 65 cm, and a second suction plate having a length of 50 cfL and a radius of curvature of 10 m was provided at the center to maintain the temperature at 40°C.

The interval between the false twisting device and the pulling device is 40 cIIL,
The take-up speed is 520 m/min.

Between the false twisting device and the pulling device, a member that engages with the yarn is
In particular, nothing was set up.

The obtained yarn had untwisted yarn portions and twisted yarn portions existing alternately.

The twist density of the untwisted yarn portion is 3000 T0n.

The average length is 70 mm, the longest is 200 m - the length ratio to the yarn is 39.4%, the yarn diameter is approximately 100 μm, the twist density of the threaded yarn part is 1950 T0n, and the average length is 107
．． The power was 5 mW, the length ratio to the thread was 60.6 mm, and the thread diameter was 128 μm on average.

The yarn obtained by the above process is further heat treated (successively following the above process, it passes through a 1-2m heating zone heated to 237°C and is taken off at 520m/min) to reduce the torque and increase the tensile strength of the yarn. After that, the fabric (structure: plain weave, warp density = 85 threads/1 nch, weft density = 82 threads/1 n)
ch) was created.

In the fabric thus obtained, the untwisted yarn portion becomes a transparent weave, and there are many areas where several untwisted yarn portions are adjacent to each other.
The pattern it creates has a warp and warp pattern, as well as a lattice pattern in which the lines of the splash pattern act as surfaces.

Although the fabric is uneven and patchy in parts, it is sensually uniform and aesthetically pleasing overall.

This fabric is hard due to the fusion in the system and the strong twist effect, so when the weight was reduced by 22% by caustic soda treatment,
It has a new and good texture that is both georgette crepe and voile made using sea island cotton.

In addition, in the above process, a traverser was provided at a position 50 mm upstream of the take-up device to protect the take-up device by changing the position in which the thread is held to the take-up device, or was it provided with a traverser that had little effect on the formation of the thread? It's something that didn't exist.

Example 2 In Example 1, the take-up device was moved from a position 40cIrL downstream of the rotation axis direction of the false twisting device to a direction 5c perpendicular thereto.
The yarn that has passed through the false twisting device is guided in the direction of the rotating shaft, brought into contact with the first rotating guide at a 45° bend, and then brought into contact with the second rotating guide at a 45° bend. Example 1 was carried out in the same manner as in Example 1 except that it was guided in the direction and engaged with the pulling device.

The untwisted yarn portion in the system was manufactured in each L by varying the distance from the yarn passing through the false twisting device until it comes into bending contact with the first rotating guide in the range of 7vtm to 300mrtt. The average length and maximum length were investigated.

The average length was approximately proportional to L between 7 m and 100 mm, and was 40.5 m 7 IL when L was 100 m 71 L.

Furthermore, when L is between 100 mm and 200 mvt, the rate of increase in average length with respect to increase in L gradually decreases, and when L is 20
In the range from 0 mm to 300 mm, the average length hardly changed and was about 70 ynrrt.

The maximum length is obtained when L is approximately equal to L between 7 mm and 2001 m, and when L is 200 mm or more and 300 mm
In the range at t, the value remained almost unchanged at 200 mrIL.

In the above, the tips of many false twist heating areas that occur over time almost all reach the first rotating guide when L is 100 m or less, and most of them reach the first rotating guide when L is 200 m or more. None of them reached the first rotating guide, and L was 1.
I found out that between 2001m from 00ryu, there are some cases where it is reached and some cases where it is not.

From the above results, the maximum reachable distance of the tip of the false-twisting heating area is 200 degrees downstream from the false-twisting device. It can be seen that it is necessary to keep the guide for bending the yarn path and guiding it to the take-off device) at least 200 mTIL away from the false twisting device.

Example 3 In Example 2, the temperature of the heating device was changed to 237°C and 2
Tests were carried out at 35°C and 2'400C to determine the maximum reach of the tip of the false twisting heating area.

At 235°C it was 100mm and at 240°C it was 250mvt.

Example 4 In Example 1, 200 m7I downstream of the false twisting device
Between the L position and the pulling device, there are one fixed guide, two fixed guides,
Four types of engaging members were provided: three, one fixed guide, and one rotary guide, and various engagement states of the threads were changed.

As a result, the presence or absence of a rotating guide and the bending contact angle had little effect on yarn formation, and when the total bending contact angle to the fixed guide exceeded 30°, the proportion of the length of the untwisted yarn portion in the yarn decreased. .

When it is necessary to bend the yarn path between the false twisting device and the take-off device, it is possible to use a fixed guide if the bending angle is 30° or less, and even if the bending angle is 30° or more, it is possible to use a fixed guide. It was confirmed that it is also possible to use a rotating guide in combination with a bending contact angle of 300 or less with respect to a fixed guide.

Comparative Example 1 An experiment was conducted under the same conditions except that the false-twisting device in Example 1 was changed to a false-twisting device using an air jet flow and a spindle false-twisting device.

As a result, there were many untwisted portions, untwisted yarn portions with a small amount of twist, and ununtwisted yarn portions where the fusion was partially peeled off.

When the yarn was observed immediately after passing through the false twisting device, various irregular yarn structures were formed in this part, such as untwisted state, untwisted state, untwisted state, etc.

In addition, strong ballooning occurred upstream and downstream of the false twisting device.

In particular, in the case of a spindle false twisting device, the yarn tension was high in the untwisted region, and there were particularly many non-twisted regions.

The obtained yarn had a strong twist pattern and appearance, and did not have a Kasuri pattern.

Comparative Example 2 A drawn multifilament yarn (75 denier, 36 filaments) made of polyethylene terephthalate was false-twisted at a false-twisting rate of 3200 T/m while applying a 4-fold overfeed under the usual false-twisting conditions.

Various experiments were conducted with heating temperatures starting from low temperatures, and at 245° C. sufficient fusion occurred to the extent that peeling occurred, but the yarn obtained was almost untwisted and had only some fused and bundled portions here and there.

Since the yarn obtained in Example 1 has a twist shrinkage of more than 10 factors, the overfeed was changed to 18 factors in the above experiment.
Although the desired yarn was temporarily obtained, it could not be obtained for a long period of time.

A slight fluctuation in yarn tension during false twisting causes a decrease in yarn tension, a decrease in the number of false twists, a decrease in twist shrinkage, and a decrease in yarn tension.As the overfeed is large, the yarn eventually becomes slack and cannot be processed. Conceivable.

In this regard, when an undrawn yarn is used, conditions can be adopted in which false twisting is performed while stretching at a low magnification to account for the twist shrinkage, so the yarn does not sag and the above-mentioned processability is good.

Comparative Example 3 In Example 1, when the stretching ratio was changed to 1.65 times, almost no alternating twist was formed.

The direct cause may be due to the high yarn tension in the untwisting region, or because alternately twisted yarn has twist shrinkage, the yarn is shorter by the amount of twist shrinkage than the stretched length of the fibers. It is necessary to draw the film at a drawing ratio smaller than the natural drawing ratio at which no unstretched state occurs.

[Brief explanation of the drawing]

FIG. 1 is a process schematic diagram showing one example of the process for manufacturing a fused alternately twisted yarn of the present invention, and FIGS. 2, 3, and 4 are process diagrams showing how a fused alternately twisted yarn is obtained by the method of the present invention. This is a schematic diagram showing the thread forming mechanism. 1: Supply device, 2: Heating bonding plate, 3: Friction false twisting device, 4
: first pulling device, 5: second heating device, 6: second pulling device, 7: fused alternately twisted yarn, 8: rotating member or/and fixed member, T: false twisting point, G: bending contact point, P : Boundary between untwisted yarn part and untwisted part, Q: Untwisting point, 1o, 1. ,
12: Time, θ: Bending contact angle, A2B: Position where the tip of the false-twisting heating area can no longer transmit the rotational force applied by the false-twisting device to its downstream side.

Claims (1)

[Claims] 1. When drawing and false twisting a thermoplastic undrawn fiber multifilament yarn, an upstream twisting yarn supply device, a heating splicing board,
Arrangement 1 in the order of the second grafting plate, false twisting device, and yarn take-off device
The yarn is drawn by using a device that has been used in the past, with the stretching ratio set by the yarn supply device and the yarn take-off device being equal to or less than the natural stretching ratio of the undrawn yarn, and the temperature of the heating splicing plate is adjusted to The temperature is such that an untwisted portion is formed and a part of the constituent filaments peels off in the untwisted region, and the second bonding plate contacts the yarn to regulate the yarn path and prevent false twist ballooning. , the yarn is cooled, and the false twisting device uses a circumscribed friction false twisting device to maintain the fusion of the yarn even immediately after passing through the false twisting device, and the yarns that have passed through the friction false twisting device first come into contact with each other. Production of fused alternately twisted yarn, characterized in that the distance to the member is 200u or more, and during untwisting between the false twisting device and the contact member, a part of the untwisted portion is destroyed to form a threaded twisted yarn portion. Method. 2. The method for producing fused alternately twisted yarn according to claim 1, wherein the member with which the yarn comes into contact for the first time is a rotating roller, and the bending contact angle of the yarn is 30° or more.