JPS601409B2 - Manufacturing method of fused alternately twisted yarn - Google Patents

Description

[Detailed description of the invention]

TECHNICAL FIELD OF THE INVENTION The present invention relates to a method for manufacturing a fused alternating combustion yarn. More specifically, the present invention relates to a method of false twisting thermoplastic fiber multifilament yarn to produce a special alternately twisted yarn that can effectively form a cloth band exhibiting a strongly twisted yarn-like texture and a light warp. S-twisted yarn portions and Z-twisted yarn portions alternate in the yarn axis direction, and the yarn portion in one of the twisting directions has a relatively long, tightly twisted yarn structure, and the yarn portion in the other twisting direction has a bulky yarn structure. The present invention relates to a method for producing a special alternately twisted yarn having a twisted yarn structure. B. Prior art and its problems There are many techniques known in the art that alternately form untwisted yarn portions and overtwisted yarn portions by false twisting yarn processing. 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. Furthermore, there are examples of false-twisting drawn fibers using a false-twisting device that applies fluid swirling flow under high excess supply, such as Hakamakai No. 51-143746 and JP-A-51 114
It is described in Japanese Patent Publication No. 3749, Japanese Patent Publication No. 53-15188, Japanese Patent Publication No. 30818-1983, and the like. In addition, there is a technique that actively applies unsteady effects to the threads that are being treated with temporary lacquer. For example, as a technique for varying the contact state between the yarn and the heating device, JP-A-49-66928
JP-A-51-15017, JP-A-52-811y, etc., as a technique for varying the twist propagating from the false twisting device toward the heating device.
34016, JP-A-49-554, JP-A-50-121,546, etc., and JP-A-49-8414 discloses a technique for varying the number of twists of yarn generated by a false twisting device. , JP-A-49-108353, JP-A-53-61745, etc., and JP-A-49-92337, JP-A-53-61745 as a technique for varying the speed of yarn passing through a false twisting device. Showa 49-92354
There are Japanese Patent Application Laid-open No. 52-66722, etc. as a technique to make the yarn to be false twisted uneven in the length direction.
Japanese Unexamined Patent Publication No. 53-8174, Special Publication No. 49-1016
There are publications such as Publication No. 54. All of the above conventional techniques form alternately twisted yarns by false twisting, but
In addition to the twisted yarn part and the Z-twisted yarn part, a large amount of untwisted yarn part like normal false twisted yarn is formed, or a relatively long untwisted yarn part is formed between the S-twisted yarn part and the Z-twisted yarn part. The twist density in the untwisted yarn portion or the over-untwisted yarn portion may be high in the center and low at both ends, or the twist density in each untwisted yarn portion or each over-untwisted yarn portion may be inconsistent. It has a defect that the average twist density of the entire yarn cannot be increased, such as the inability to form a high length fraction of the end-untwisted yarn portion of the entire yarn. Alternatively, the yarn may have a twist in the direction of false twisting, but it has decomposed to the extent that the false twist crimps are exposed and is formed as an untwisted yarn portion that has lost its tightness. Although the fibers have a twist in the direction of scale twisting, the fibers are strongly fused to each other and are decombusted without revealing the false twist crimp, and are formed as an over-twisted yarn portion that has lost its bulk. It had a defect in that it was not possible to clearly form a difference in form between the untwisted yarn portion and the overtwisted yarn portion. 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. It is thought that this is because the formation mechanism of alternately twisted yarns itself was hardly noticed. The alternately twisted yarn obtained by the present invention seeks a preferable high-twisted yarn-like effect in the yarn structure in an alternately twisted state consisting of an untwisted portion and an over-untwisted portion, and a morphological difference between the untwisted portion and the over-untwisted portion. The aim is to obtain a favorable vertical effect. That is, an object of the present invention is to obtain a method for producing a fused alternating yarn that exhibits an excellent strong twist-like texture and a light iron pattern, and can also exhibit a well-developed light vertical pattern. Another object of the present invention is to
It is possible to form over-twisted yarn portions, and even during actual operation at a multi-spindle level, the variation in average length of each ununraveled yarn portion and over-untwisted yarn portions formed between bells is relatively uniform. The object of the present invention is to provide a novel method for producing fused alternately twisted yarn, which is extremely useful in actual operations and can reduce the production costs. Even when an alternately twisted yarn having relatively long S-twisted yarn portions and Z-twisted yarn portions is used as the warp of a fabric, the S and Z-twisted yarns are unlikely to be canceled out by the striations, and the proportion of the S-twisted yarn portions and Z-twisted yarn portions remains. It has a high yarn content and can fully exhibit the above-mentioned strongly twisted yarn-like texture and well-developed light powder pattern in the fabric. In addition, each S/Z twisted yarn portion of the yarn obtained by the present invention can have a relatively long average length as described above, but the individual lengths can be formed with large variations, resulting in a well-tailored pale yarn. It can exhibit a vertical pattern. Ha
Structure of the present invention In order to achieve the above object, the present invention has the following structure. "When drawing and false twisting a thermoplastic undrawn fiber multifilament yarn, the yarn is The stretching ratio set by the supply device and the yarn take-off device is set to be equal to or lower than the natural stretching ratio of the undrawn yarn, and the temperature of the heated filament plate is set such that the yarn forms an untwisted part due to fusion and The temperature is set at such a temperature that some of the constituent filaments are separated in the untwisting process, and the second bushing plate controls the yarn path by contacting the yarns to prevent false twist ballooning, and the yarn is cooled, and the false twisting device is A type friction false twisting device is used to maintain the fusion of the yarns even immediately after passing through the false twisting device, and the distance to the member with which the yarn that passes through the friction false twisting device comes into contact for the first time is set to 100 sides or more and 20 sides. A method for producing fused alternating rattan yarn, characterized in that part of the untwisted part of the yarn is broken in the untwisting area between the false twisting device and the contact member to form an over-twisted yarn part.'' In the invention, first, it is necessary to use an undrawn yarn as the starting yarn and to draw it at a magnification equal to or lower than the natural stretching ratio. The reason for this is that the thermoplastic filament fiber has a natural draw ratio or less, that it is easy to cause fusion even at relatively low temperatures, and that 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 undrawn yarn spun by conventional low-speed spinning, highly oriented undrawn yarn spun at high speed, and the like. Next, the temperature of the heating yarn 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 unlacquered region. More specifically, it refers to the temperature at which the filaments reach the melting point of the yarn and are fused to each other while maintaining their fiber shapes. If such a false untwisting temperature is adopted, if a large deformation of untwisting is applied to the multifilament yarn, whose fibers are fused together in the twisted state, the twisted yarn structure will not be able to undergo large deformation strain, and the fibers will be Poorly structured areas, ie fused areas, peel off. Next, in the present invention, the second thread board has a thread 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 twill 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 yarn reinforcing 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, a particularly long fused portion is formed in the yarn.
12451y Atsushi In order to apply relatively strong heat to form a relatively strong fusion bond, forced cooling is particularly required for such a second twill yarn plate. Here, cooling is sufficient if the temperature is below the secondary dislocation point of the yarn, which is commonly used by those skilled in the art. If the second bush board is not installed,
If the fused yarn is passed through a false twisting device in a fused state, the yarn will return to an almost untwisted state, which is not preferable. Next, in the present invention, it is 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 and fused portion to give a strongly twisted appearance and feel. Next, in the present invention, it is necessary to set the distance between the false twisting device and the first contact member to be at least the low rib and less than 200 degrees. The length of the ununtwisted and fused portion is less than 20 lengths, and the average length is medium to emphasize the medium mochi pattern and the highly twisted appearance and texture. . In this respect, the special machine No. 12451y, Sho 54-1, invented earlier.
Is the average length of the untwisted and fused portions relatively shorter than that of the present invention? It is a long one. Therefore, the material of the present invention has an average length that is intermediate compared to those of these advanced inventions. In addition, the ballooning prevention means prevents ballooning in the untwisted region between the tentative combustion device and the first contact member and maintains a stationary state, thereby destroying a part of the unscaled and fused portion and causing the overtwisted yarn to part can be formed. Note that the first contact member may be any member as long as it can prevent the rotation of the yarn in the untwisting castle.
A rotating roller having an angle of 0° or more may be used. D. Functions and Effects of the Present Invention According to the findings of the present inventors, the formation of alternate combustion yarns due to false twisting is caused by the false twisting device and upstream thereof, but such causes can be actively eliminated. As mentioned above, there are a number of conventional techniques that have been used to generate this effect, but 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 times when an unscaled yarn portion is formed, times when an overly twisted yarn portion is formed, times when a non-twisted yarn portion is formed, etc. Various conditions occur. The formation of the unscaled yarn portion is also diverse, and can be roughly divided into cases where the unscaled yarn portion that is being formed rotates in the false twist direction commensurate with its twist density, and cases where the unscaled yarn portion rotates less than that. In the latter case, there is a decrease in the number of twists upstream of the false twisting system. Further, the formation of the over-twisted yarn portion is accompanied by an increase in the number of twists upstream of the false twisting device. Also,
The untwisted yarn portion may be formed as a transient phenomenon between the untwisted yarn portion and the overtwisted yarn portion, or may be clearly formed intermittently. 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. An over-twisted yarn portion is formed when an unscaled yarn portion is formed immediately downstream of the temporary tensioning device and the downstream end portion of the unscaled yarn portion is untwisted and formed sequentially. If an untwisted yarn portion exists downstream of the unscaled twisted yarn portion, the untwisted yarn portion may be twisted and formed. The untwisted yarn portion may be formed by the twists of the partially untwisted yarn portion and the overly untwisted yarn portion offsetting each other. In the prior art, there are a wide variety of alternatively twisted yarn formations as described above.
The defect was as described above. On the other hand, in the present invention, we have found that it is most efficient 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, and we have developed this method. This method has succeeded in continuing almost all the time, and further brings the untwisted yarn portion that involves rotation into a state almost equivalent to the so-called false-twisting state upstream of the false-twisting device. Looking at it from another perspective, the state in which the false twisting region extends downstream of the false twisting device is maintained at all times. In this way, the tip of the false twisting region located downstream of the false twisting device rotates, and the rotation is applied to the rear end portion of the previously formed untwisted yarn portion and the tip portion of itself. While untwisting and sequentially forming over-untwisted yarn portions, the tips of the false-twisted portions move in the downstream direction. The rotation of the tip of this false twisting area will eventually stop when it is gripped by a take-up roller, comes into contact with a guide or the like, or the rotational force applied by the false twisting device is no longer transmitted. Even if the rotation of the tip of the false twisting area stops, the false twisting device continues to apply rotational force, so the next moment a new scale is created between the tip of the false twisting area and the false twisting device. A twist point is generated, that point becomes the tip of a new false twisting castle, and the above phenomenon is repeated, resulting in an alternately twisted yarn in which partially untwisted yarn portions and overly twisted yarn portions are alternately formed. Under such an alternate twist yarn forming mechanism, no untwisted yarn portion is actually formed. 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, the yarn is always in the false twisted state at least in the vicinity of the false twisting device, and Downstream of the imparting device, the downstream end of the yarn portion that is engaged with a binding material that prevents the rotation of the yarn from propagating downstream, and that is in the false-twisted state is located at the most downstream end where it can be located. The invention is characterized in that the downstream end reaches the engaging member in some cases and in other cases does not reach the engaging member when the downstream end reaches the engaging member. Looking at it from a different perspective, the special method for producing alternately twisted yarn of the present invention is such that the yarn is always in a false-twisted state immediately downstream of the false-twisting device, and is in the false-twisted and twisted state downstream of the false-twisting device. The most downstream point at which the thread can be located as the thread progresses and exhibits the rotational behavior described above (the point at which rotation stops)
The downstream end of the yarn portion in the false twisted state may or may not reach the engagement member that prevents the rotation of the yarn from propagating downstream over time. In this case, the rotation of the tip of the false twisting castle is stopped by engaging with the engaging part village, or by the false twisting device. Machining is performed in a mixture of two cases: a case in which the applied rotational force is no longer transmitted and the object stops on its own.
A more detailed explanation will be given below with reference to the drawings. FIG. 1 is a process schematic diagram showing an example of the process for manufacturing a fused alternately twisted yarn of the present invention, in which 1 is a supply device, 2 is a heating bushing board, 3 is a friction false twisting device, and 4 is a first A taking device, 5 is a second heating device, 6
is the second take-off device, and 7 is the fused alternately twisted yarn. A second yarn reinforcing plate (not shown) is provided between the heating splicing plate 2 and the friction 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. Although the first pulling device 4 itself can be used as a member to prevent the rotation of the yarn from propagating downstream, it is provided separately between the friction false twisting device 3 and the first pulling device 4, as indicated by a broken line. An engagement member 8 may also be provided. If this engaging member is provided separately, a rotating body such as a rotating guide that rotates as the thread runs is used as the engaging member, but it has a high effect of preventing the thread from rotating, and it also provides less passing resistance to the thread. It is preferable that the running yarn is brought into winding contact with the rotating body to prevent the rotation of the yarn from propagating downstream from the rotating body. Since the friction false twisting device 3 applies rotational force to the yarn, it also tries to rotate the yarn downstream of the false twisting device (rotation in the direction of temporary twisting); It is possible for the yarn to rotate and continue in the false-twisted state without being untwisted. Such a false-twisted state (untwisted) is subject to the action of untwisting as appropriate, but when the untwisted yarn portion is decombusted. The twist density of the unscaled twisted yarn portion as a whole does not gradually decrease, but a portion is decombusted, and the pseudodensity itself of the unscaled yarn portion gradually becomes short without substantially changing, and the decombusted yarn portion It is best to twist the yarn so that it absorbs a lot of twist and becomes an over-twisted yarn portion that gradually becomes longer, and the present invention makes use of this. In order to produce this kind of untwisting, it is preferable that the scale twisted yarn portion has high cohesiveness and high torsional rigidity, and once untwisted, it loses the cohesiveness and has low torsional rigidity. For this purpose, it is necessary, for example, to provide an appropriate degree of fusion, that is, a degree of fusion that causes part of the fusion in the untwisted state to peel off at the scale twisting. 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 castle located downstream of the false twisting device rotates, and the rotation is applied to the rear end portion of the previously formed end-untwisted yarn portion and the self-twisting part. While untwisting the tip portion of the tentatively twisted castle and sequentially forming over-untwisted portions, the tip of the tentatively fired twisting castle moves in the downstream direction. The rotation of the tip of this false twisting area will eventually stop 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 area stops, the temporary combustion device continues to apply rotational force, so a new solution is created between the tip of the false-twisting and burning area and the false-twisting device at the next moment. A twisting point is generated, that point becomes the tip of a new false twisting area, and the above phenomenon is repeated, resulting in an alternately twisted yarn in which partially untwisted yarn portions and overly twisted yarn portions are alternately formed. In the present invention, there are two cases in which the rotation of the tip of the false twisting castle is stopped by engaging with the engagement material, or when the rotational force applied by the false twisting device is no longer transmitted and the rotation stops on its own. A joint part is provided to prevent the rotation of the thread from propagating downstream so that processing can be performed in a mixture of two cases. FIGS. 2, 3, and 4 show the formation mechanism of alternately twisted yarns in this manner from time to to t, t2...
This is shown schematically over time, where T is the false twisting point and G is the false twisting point.
is the rotation prevention point by the engaging portion village, P is the boundary between the partially untwisted yarn portion and the excessively untwisted yarn portion, and Q is the point where untwisting occurs. In FIGS. 2 to 4, FIGS. 3 and 4 are at time t. It is assumed that the tip P of the false-twisting area has reached point G at , and Fig. 2 shows the tip P of the false-twisting area at time to.
It is assumed that , has reached position A (uncertain) where it no longer transmits the rotational force applied by the preliminary combustion device, and the downstream side (take-up side) of P is the over-twisted yarn part. , P, is in an unscaled state because it is located upstream of Karito Kaori Castle. Rotational force is applied at point T, and point G (Figures 3 and 4)
Alternatively, since point P located at point A (Fig. 2) cannot be rotated now, untwisting begins at an uncertain point Q between point T and point P. Thereafter, points P and Q proceed downstream at a distance. The decombusted yarn portion is in an over-untwisted state and the torque is balanced, and both ends of the over-untwisted yarn portion are designated as P2 and P3. P
, ~ P2 proceeds downstream as an untwisted yarn portion, and P2 ~ P2
The length between 3 and 3 is an overly decomposed fiber that increases in length and moves downstream. Point P3 advances downstream as the tip of a new false twisting area;
Finally, it reaches point G again (state of time t4 in Fig. 2, state of time t4 in Fig. 3) or an uncertain point A (state of time t4 in Fig. 4) where no rotation is transmitted. Therefore, as in the case of time, a state is reached in which rotation cannot be propagated, and a new untwisting point Q2 (uncertain) is formed, and the same phenomenon is repeated. In actual processing, there are various ways in which the length of the over-twisted yarn portion between P2 and P3 increases while progressing downstream.
For example, Fig. 2 shows a case where untwisting occurs only at point P3, and the over-twisted yarn portions P2 to P3 are increased in length toward the upstream direction (toward the false twisting device side), and the length is increased in the downstream direction. In addition, as shown in Fig. 3, untwisting occurs preferentially at the initial point P2, and the over-twisted yarn portions P2 and P3 progress toward the downstream side with their length increasing. However, after a certain time (t2 or t2'), the point P2
Therefore, scale twisting cannot occur, and untwisting occurs at point P3 (that is, scale twisting increases in length toward the upstream direction), and furthermore, Figure 4 shows that scale twisting increases as time progresses. ，
The over-twisted yarn portions P2 to P3 proceed further downstream or upstream, or alternatively proceed downstream and upstream.
is formed by increasing the length in both the upstream and downstream directions, and the tip P3 of the new false twisting area advances downstream, and these various aspects occur as a mixture and combination within the same spindle. It is something. Under the alternating yarn forming mechanism of the present invention, the scale twist point Q occurs at a relatively random and equal probability anywhere between T and point G or point A, and the position of point A itself Each untwisted yarn portion formed because it is also uncertain. The length distribution of the over-twisted yarn portion is more like a rectangular shape than a normal distribution, and has a large variation.Essentially, the above-mentioned formation mechanism consists of an alternating pattern to obtain a well-rounded pattern. It is ideal for obtaining twisted yarn. When carrying out the present invention, when the downstream end of the yarn portion in the false twisted state always engages with the engagement member when it advances downstream, the rotation of the tip is stopped. Therefore, the length of the untwisted yarn portion to be formed is regulated, and at the same time, the length of the over-twisted yarn portion is also regulated, so relatively long untwisted yarn portions and
This is not preferable as it is not possible to create an over-twisted yarn portion, or if the yarn always stops rotating on its own before engaging with the engaging member, that is, the end point P3 of the false twisting area is completely untwisted. If it is free, there will be an undesirable difference in the average length of the unscaled twisted yarn part and overly twisted yarn part in each bell during multi-spindle processing. It is important to choose. In the end, only when the tip P3 of the false twisting region has progressed relatively abnormally compared to that during normal processing and would form a maximum length longer than desired if left as it is, it is allowed to reach point G, and then a new twist is made. In order to reduce the above-mentioned difference between spindles during actual operation, forcing the occurrence of the untwisting point Q and setting the upper limit of the length of the untwisted yarn portion formed in this way as desired. It becomes extremely effective. A specific embodiment of the yarn obtained by the present invention utilizes false twisting, so it is made of long fibers with false twist crimp, and the Z-twisted yarn portion (or S-twisted yarn portion) has a bran winding form of the fibers. This is the tightly twisted yarn part that matches the yarn structure, and the S-twisted yarn part (
Alternatively, the Z-twisted yarn portion) is a multi-filament yarn that is a bulky twisted yarn portion where the crimp form of the fibers is exposed, and it is determined whether either of these S or Z is a tightly twisted yarn portion or a high-twisted yarn portion. This can be set by appropriately selecting the direction of false twisting. Moreover, the average length of each part can be made relatively long, and the average lengths can be made uniform among the weights, and the lengths of the individual parts can also be made to have variations. The specific embodiment of the manufacturing method of the present invention can be achieved by paying attention to and observing the above-mentioned phenomena and selecting the false twisting mode and conditions (in particular, the installation position of the engaging member, etc.). ). Listing the findings obtained in the present invention, the following aspects and conditions are preferred. (1) The twist density of the untwisted yarn portion remains almost the same as the twist density of the pre-twisting, so it is preferable that the number of false twists is high, but if the number of false twists is too high, double twisting will occur and false twisting will occur. The number of twists passing through the twisting device fluctuates, or the twisting force of the false twisting device approaches or exceeds the gripping force limit, causing intermittent twisting, which may cause untwisted yarn portions to be formed.As a guideline: It is preferable that the number of false twists is slightly lower than that of normal false twisting processing.'2} Vibration of the yarn during processing, especially ballooning near the temporary combustion device, may be caused by cutting the unscaled yarn portion, or This is undesirable as it may cause loss of stability in processing, so it is preferable to prevent ballooning from occurring as much as possible, and to the extent that ballooning cannot be seen with the naked eye. This is undesirable because the twists in the twisted yarn portion and the over-untwisted yarn portion cancel each other out, the over-unraveled lacquered yarn portion does not have a high twist density, or the yarn is untwisted at the same time as it passes through the false twisting device. It is preferable to weaken the yarn tension, and consideration must be given to the method, structure, processing conditions, etc. to reduce the passing resistance of the false twisting device and guides. {4} In the false twisting device and its upstream, strong abrasion When applying an action or deforming with a large curvature, the above

[In addition to matters similar to item 31, the fusion bond may peel off or the twisted structure may be destroyed in the twisted state, resulting in a decrease in centering property, and the twisting may occur at the same time as passing through the false twisting device. This is not desirable 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 item 1, when performing false lacquer processing on thermoplastic fiber multifilament yarn, if the process is preferably carried out in accordance with the above item, the yarn passes through a false twisting device. Even after the twisting, the yarn can be kept in a false-twisting state at all times in the vicinity of the false-twisting device, and the rotation of the yarn installed at an appropriate position downstream of the false-twisting device can be prevented from propagating downstream. By engaging the yarn with the engaging member, the alternately twisted yarn can be formed according to the yarn forming mechanism as described above, and the fused alternately twisted yarn, which is the intended purpose of the present invention, can be successfully produced. Note that the earlier patent application 1245/1984, which is the basic invention of the present invention,
No. 1- and its improved invention, Japanese Patent Application No. 125/1983
The relationship with No. 35y is that in the present invention, the distance between the false twisting device and the first contact member is set to 100 mm or more and less than 200 mm.
This has the unique effect that the length of the fused, untwisted portion can be made medium in length compared to the above two prior applications. Hereinafter, the specific configuration and effects of the present invention will be explained using Examples. Example 1 Polyethylene terephthalate was melt-spun and spun at a rate of 300 spindles/min to produce a multifilament yarn having a thickness of 137 denier and 36 filaments. This yarn was given 320 false twists using a false twisting machine equipped with multiple keys.
0T/m, heating temperature 24000, stretching ratio during processing 1.
False twisting was performed at setting 4. The heating device is a yarn reinforcing plate with a length of 1.5 m and a radius of curvature of 30, with a semicircular groove on the radius 2 side, and the false twisting device is a tri-koji circumscribed friction false twisting device. The distance between the heating device and the provisional device was 65 cm, and a second hair plate with a length of 50 cm and a radius of curvature of 10 cm was provided in the center to maintain the distance of 40 cm. The interval between the false twisting device and the take-off device is 40 mm, and the take-off speed is 52 h/min. The obtained yarn had unscaled yarn portions and overly twisted yarn portions existing alternately. The average length of the end-untwisted yarn by spindle ranged from 7 to 92 sides. This yarn is used as a striped yarn for plain weaving (warp is multifilament yarn: 50 denier - 24 filaments, warp density 15)
0 pieces/in. Twill density 85 strands/in. ), when I created
There was a clear difference between the woven fabric using threads with an average length of 700 mm and the woven fabric with 92 mm. Next, a diameter
A 0 Yanagi rotating guide was provided, and the thread was wound at approximately 360° and brought into contact with it for processing. As a result, the average length of the untwisted yarn portion was 62 for the 7-length yarn mentioned above, and 68 for the 92-willow yarn. Similar to the above, a comparison was made using woven fabrics, but there was almost no difference between the two. The heating temperature of the weight that produced the yarn with the longest average length of the unscaled yarn portion was 240 oo, while the heating temperature of the weight that produced the shortest yarn was 2,370 oo. When the setting of the heating device was set to 24300 and the experiment was carried out without using a rotation guide, it was possible to produce a yarn of 91 sides using the same spindle that produced the yarn with the average length of the untwisted yarn portion of 7 ratios.
As a result of the above implementation, the difference in the average length of the untwisted yarn portion between the spindles is
It was found that the main cause was the difference in heating temperature, and that the difference between the bells could be reduced by using a rotating guide. Furthermore, using one weight and a rotating guide, the distance L from the time the yarn passes through the false twisting device to the point at which the rotating guide reaches the point where the yarn passes through the false twisting device at heating temperatures of 237C0 and 24000C is determined in the range of 7 to 300 degrees. The experiment was carried out with various modifications, and the average length and maximum length of the untwisted yarn portion in the yarn produced in each L were investigated. In the case of 23,700 (24,000), the average length is approximately proportional to L when L is between 7 and 10 ribs (120 side), and when L is on the 100 side (12 ribs), the average length is 40.5 ribs (51 willow). 〉. Furthermore, when L is between 10 ratios (12 ratios) and 20 ratios (25 ratios), the rate of increase in average length with respect to increase in L gradually decreases, and when L is 20 ratios, In the range from (250 fences) to 300 fences, the average length hardly changes, about 70 fences.
It was the rib (92 side). On the other hand, the maximum length is approximately equal to L when L is between 7 skins and 20 skins (250 sides), and when L is over 200 skins (25 ribs) and up to 300 ribs, it is almost the same as L. The number remained unchanged at 20 ki. From this, it can be seen that almost all of the tips of the false-twisted parts, which occur in large numbers over time, reach the rotation guide when L is 10 or less (20 ribs);
50 skins) or more, almost all of them do not reach the rotation guide, and L varies from 10 feet (12 skins) to 20 feet (2 feet).
It was found that there was a mixture of cases in which it was reached and cases in which it was not reached among the five proboscises over time. 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 yarn parts, less twisted yarn parts, over-twisted yarn parts, and untwisted yarn parts where the fusion was partially peeled off. When the yarn was observed immediately after passing through the false twisting device, various types of yarn structures were irregularly formed in this portion, such as untwisted state, excessively 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 in the untwisting area was high, and there were particularly many non-twisted portions. The resulting yarn did not have a highly twisted texture or appearance, nor did it have a scarlet color. Comparative Example 2 Stretched multifilament yarn made of polyethylene terephthalate (75 denier-36
The filament was subjected to false twisting at a false twisting rate of 3200 T/m while giving an overfeed of 4% according to the usual false twisting conditions. Various experiments were carried out starting from a low heating temperature, and 245Co produced sufficient fusion to the extent that it could be peeled off, but the yarn obtained was almost untwisted and had some fused parts here and there. Since the yarn obtained in Example 1 had a twist shrinkage of 1% increase, the overfeed was changed to 18% in the above experiment, but although the desired yarn was temporarily obtained, it could not be obtained if continued for a long time. There wasn't. 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 respect, when a wire-drawn yarn is used, conditions can be adopted in which false twisting is performed while stretching at a low magnification to account for the twisting shrinkage, so the yarn does not sag, and the above-mentioned processability was good. Comparative Example 3 In Example 1, when the stretching ratio was changed by 1.6 stitches, almost no alternating combustion was formed. We believe that the direct cause is the high yarn tension in the untwisting region, but since alternately twisted yarn has twist shrinkage, the yarn is shorter by the amount of twist shrinkage than the stretched length of the fibers, so the stretching set on the device It is necessary to draw the film at a stretching ratio of 4 mm, which is higher than the natural stretching ratio, at which no unstretched state occurs.

[Brief explanation of the drawing]

FIG. 1 is a process schematic diagram showing an example of the process for producing a fused alternately twisted yarn according to the present invention, and FIGS. This is a schematic diagram showing the mechanism. 1: Supply device, 2: Heating yarn reinforcing plate, 3: Friction false twisting device, 4
: first pulling device, 5: second heating device, 6: second pulling device, 7: fused alternately twisted yarn, 8: engaging member, T: false twisting point, G:
Rotation blocking point, P...Limit between untwisted yarn portion and overtwisted yarn portion, Q...Untwisting point, to, t,, t2, t3.
...: Time, A: Position where the tip of the false twisting castle no longer transmits the rotational force applied by the false twisting device to the downstream. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. When drawing and false twisting a thermoplastic undrawn fiber multifilament yarn, an upstream twisting yarn supply device, a heating splicing plate,
Using a device arranged in the order of a second grafting plate, a false twisting device, and a yarn take-off device, the drawing ratio set by the yarn supply device and the yarn take-off device is set to be less than or equal to the natural drawing ratio of undrawn yarn. The temperature of the heated splicing plate is such that the yarn forms an untwisted part due to fusing and a part of the constituent filaments peels off in the untwisted yarn, and the temperature of the heated splicing plate is such that the yarn is fused and a part of the constituent filaments is peeled off. By controlling the yarn path and preventing 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 distance to the member with which the yarn that has passed through the frictional false twisting device comes into contact for the first time is set to 100 mm or more and less than 200 mm, and a part of the untwisted portion is destroyed in the untwisted area between the false twisting device and the contact member. 1. A method for producing a fused alternately twisted yarn, which comprises forming an over-twisted yarn portion. 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.