JPS6140769B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing processed yarn by false twisting and crimp processing using incompletely drawn yarn made of a thermoplastic polymer. It is known that when an undrawn yarn made of a thermoplastic polymer is drawn at a draw ratio lower than the natural draw ratio, an incompletely drawn yarn is obtained in which each filament has a thick fiber portion and a thin fiber portion. Attempts have been made to false-twist and crimp incompletely drawn yarn to create textured yarns with different dye shading and bulkiness, but in such cases, a large amount of fuzz is generated during the false-twisting and crimping process, resulting in the process being interrupted. It has the disadvantage of poor permeability,
This improvement is desired in the increasingly diversified stage of fabricated yarn production. The present inventors have arrived at the present invention as a result of research in view of the above points, and the first object of the present invention is to stretch an undrawn yarn made of a thermoplastic polymer at a stretching ratio equal to or lower than the natural stretching ratio. A method for producing a processed yarn, which is characterized in that it is subjected to a drawing step and a twisting step to obtain an incompletely drawn yarn in which thick fibers and thin fiber portions are present in each filament, and then subjected to false twisting and crimp processing. It is to provide. A second object of the present invention is to provide a method for producing processed yarn, which comprises twisting and integrating the incompletely drawn yarn and the drawn yarn, and then subjecting them to false twist and crimp processing. Then, the third object of the present invention is to
It is an object of the present invention to provide a method for producing processed yarn, characterized in that the yarn is false-twisted in the same direction as the twisting direction and subjected to false-twist crimp processing. Furthermore, another object of the present invention is to provide a method for manufacturing textured yarn, which is characterized in that, in the first and second objects, false twisting is performed in a direction opposite to the direction of twisting, and false twisting and crimp processing is performed. It is. Generally, an undrawn yarn made of a thermoplastic synthetic polymer has a natural draw ratio due to its drawing behavior, and if it is drawn at a draw ratio lower than this, it will not be drawn uniformly, and the thick and thin fiber portions will separate into individual fibers. A partially drawn yarn present in the filament is obtained.
In terms of drawing conditions, the degree of thickness of the thick fiber part and the thin fiber part is greatest when the drawing temperature is around the second-order transition temperature or lower, and the thick fiber part has molecular orientation comparable to that of undrawn fibers. , and the thin fiber portions have a molecular orientation comparable to that of stretched fibers. The difference in molecular orientation between the thick fiber portion and the thin fiber portion generally increases as the molecular orientation of the undrawn yarn decreases. In addition, the ratio of these thick fiber portions and thin fiber portions in each filament is such that when drawing is carried out at or below the second-order transition temperature, only the thick fiber portion exists at a drawing ratio of zero; When stretching is carried out at a draw ratio comparable to the natural draw ratio, all the fibers become thin fibers or become close to it, so the draw ratio can be changed by appropriately setting the draw ratio.
The length of such thick fiber portions varies depending on the oil agent added during the spinning process and the stretching conditions, and generally cracks occur during the stretching process. Also, Special Publication No. 36-21817 and Special Publication No. 42-
When treated with an oil having the composition described in No. 8731, the length of thick fibers and thin fibers becomes small, and can even be reduced to about 1 mm or less, making it difficult for this to occur. With natural oils, it can be made as long as 5 to 10 cm. In addition, in the stretching process, when preliminary stretching is performed prior to the main stretching, the fiber generally has short thick fiber portions or thin fiber portions. In general, the closer the drawing temperature is to the second-order transition temperature, the longer the fibers will have thick fiber portions and thin fiber portions. When a bundle of individual filaments having thick fiber portions and thin fiber portions is drawn with a small amount of cohesiveness, each filament exhibits the tendency to be drawn independently. The tendency for the positions of thick fibers and thin fibers to be randomized on the yarn increases, and in the extreme, it becomes random like a marbling tone. Conversely, when the undrawn yarn is stretched with high cohesiveness, the positions of the thick fiber portions and the thin fiber portions on the yarn tend to be aligned. When false-twisting and crimping incompletely drawn yarns such as those described above, there is a tendency for more fuzz and thread breakage to occur than with normal, uniformly drawn yarns, and experiments have shown that this is a major negative factor in industrial terms. The results were revealed. This is thought to be mainly due to the presence of small portions of molecular orientation in the incompletely drawn yarn, and the fact that the phases of small and large molecular orientations are out of sync or slightly out of phase. . Fuzz and yarn breakage during the above false twisting and crimp process cause trouble not only in the false twisting and crimping process but also in subsequent processes, so it is necessary to at least prevent or reduce the occurrence of such troubles. As a result of research into this problem, it has been found that a significant improvement can be made when incompletely drawn yarn is twisted and then pre-crimped. The twist is per 1m
The number of twists is preferably about 100 twists or more, preferably about 200 to 700 twists, and the number of twists is sufficient to give the yarn cohesiveness. By twisting as described above, even if the reduction in fuzz during the false twist and crimp process is relatively small, yarn breakage and subsequent troubles are significantly reduced, and furthermore, fuzz is generated frequently during the false twist and crimp process. However, it has the benefit of creating a state with fewer troubles. It has also been found that when the incompletely drawn yarn is further twisted and subjected to false twist crimp processing in this way, it is possible to obtain the benefits of producing various new processed yarns. The first novel textured yarn of the present invention is obtained by twisting an incompletely drawn yarn, applying false twist in the direction of the twisting, and simultaneously stretching it. . This textured yarn is easily produced when the total draw ratio after false twisting and crimp processing is around or higher than the natural draw ratio of the undrawn yarn. This processed yarn is an incompletely drawn yarn, and the thick fiber portion is mainly dyed in a dark color, and the thin fiber portion is mainly dyed in a light color, so it has the ability to dye shades. A bulking effect is obtained due to the loop fibers floating above the core part of the processed yarn, which is thought to be caused by a phase shift in the thick part of the fully drawn yarn.
In addition, there is a grain effect due to the ununtwisted effect due to the false twisting in the same direction as the twisting, a leveling effect of the grain that reduces the petering of the grain due to the wobbling of the grain on the cloth, and a smoothing effect of the grain that is not untwisted. The bulking effect of the twisted portion and the bulking effect of the loop fibers at the end are added, and the bulkiness and texture can be improved. This processed yarn can also be modified into a processed yarn with more fluff. In other words, one method is to increase the draw ratio in the preliminary crimping process, but increasing the draw ratio will reduce the shade dyeing ability, so this is not a good method if you strongly desire a heathered effect. isn't it. The second method is to perform a slight elongation treatment to fluff the material after false twisting and crimp processing, and good results can be obtained. Another method is to take advantage of the fact that the smaller the molecular orientation of undrawn yarn, the more fluff is likely to occur.In the case of polyester, undrawn yarn with a birefringence of about 0.01 to 0.03 is used. This results in favorable results. In addition, when undrawn polyester yarn with a birefringence of 0.01 to 0.05 is used for this processed yarn, the yarn tends to stick during false twisting and crimping. It can also be modified. Next, the second novel textured yarn of the present invention is obtained by twisting the incompletely drawn yarn, applying false twisting in the opposite direction to the twisting, and simultaneously stretching the yarn. It is caused by As before, this processed yarn has dark and light color ability and a bulking effect due to the floating loop fibers, and has great stretchability due to the over-untwisting effect. Similarly to the above, it is also possible to modify the processed yarn to have a lot of fuzz or a partially sticky processed yarn. Next, the third novel processed yarn of the present invention is produced by twisting the undrawn yarn and stretching it at a draw ratio lower than the natural draw ratio to obtain an incompletely drawn yarn, and then false-twisting the yarn and stretching it simultaneously with the false-twisting. It is made to last by crimping.
This processed yarn has a characteristic that the boundary between the dark color dyeable part and the light color dyeable part is clear without blurring.
There are benefits in using heather. When false twisting is performed in the opposite direction to twisting, there is also the benefit of over-untwisting. The fourth novel textured yarn of the present invention is obtained by twisting a drawn yarn into an incompletely drawn yarn, and then false twisting and crimping the yarn in the same direction as the twisting. In this processed yarn model, the drawn yarn forms the core yarn,
The incompletely drawn yarn is slightly stretched during the false twist crimp process to become side yarns, and because the side yarns are longer than the core yarn, it becomes a bulky yarn with many floating loop fibers. In addition, the side yarns have a heather effect that allows for shaded dyeing, and the processed yarn as a whole has an untwisted effect. The fifth novel textured yarn of the present invention is obtained by twisting a drawn yarn into an incompletely drawn yarn, and then false twisting and crimping the yarn in the opposite direction of the twisting.
This processed yarn has side yarns that are longer than the core yarn, resulting in a bulky yarn with many floating loop fibers, and the side yarns also have a heather effect that allows for dark and light dyeing, making it possible to obtain a processed yarn that is untwisted as a whole. . In addition, the present invention can create processed yarn with a new texture by reducing the number of twists during heat setting in the false twist crimp process compared to the general false twist crimp process. can. The texture of the processed yarn obtained by this method has fewer crimps than normal processed yarn, so it has many elements of the effect of non-crimped yarn such as drawn yarn, and especially The loop fibers provide bulk to the center of the yarn, which has little bulge, giving it a spun-like and silky texture. For general false twisted yarn, the number of twists per meter during heat setting is T when the yarn denier of the yarn is D.
is given by the formula T=K/√, and then K
is about 28,500 to 30,500, but in order to make a processed yarn with a spun-like or silky texture, the required K is about 10,000 to 26,500.If you want to particularly emphasize the silky texture, K = about 10,000 to 22,000, or about 10,000 to 22,000, and a spun-like texture. If you want to emphasize K, you can set K to about 20,000 to 26,500. When it is desired to particularly reduce fluff in the processed yarn of the present invention, it is better to increase the birefringence of the undrawn yarn.
It is desirable to use undrawn yarn with a diameter of about 0.025 or more, preferably about 0.03 to 0.04 or more. On the other hand, when it is desired to enhance the contrast between the grains of dark and light dyeing, it is not preferable that the birefringence of the undrawn yarn is too high, such as 0.06 or more, and the maximum contrast can be obtained at a birefringence of 0.025 to 0.030. In the present invention, when an incompletely drawn yarn is made from an undrawn yarn, the dispersion between the drawing weights of the heathered effect, which is the thick fiber part and the thin fiber part, is reduced by the so-called hot roller drawing machine rather than by the drawing pin method. Stretching by roller method generally gives smaller and better results. However, even in the case of the drawing pin method, if the diameter of the drawing pin is relatively large, such as 30 to 60 mm or more, or if the drawing machine uses the drawing pin after the preheating heater, the variation between the weights may be reduced. An incompletely drawn yarn can be obtained. Next, in the false twist crimp process, it is best to use the heater temperature used for false twist crimp processing of drawn yarn or stretched false twist crimp processing, and generally in the case of polyester fibers, the temperature is about 180 to 210°C. However, if a cohesive portion is desired, the temperature may be further increased, and if a low-crimp yarn is particularly desired, an even lower temperature may be used. The present invention will be explained below using examples. Example 1 A polyester polymer is spun from a 48-hole spindle to create an undrawn yarn, and this undrawn yarn is naturally stretched using a hot roller type roller drawing machine that does not have a heater between the hot roller and the draw roller. Stretching is carried out below the stretching ratio to create an incompletely drawn yarn, which is then twisted and then 1 m long of 190
Pass through a one-stage heater false twister heated to 100 °C.
A semi-dull 150 denier, 48 filament processed yarn was obtained by false twisting and crimping at a yarn speed of m/min. Table 1 shows the relationship between the physical properties of the undrawn yarn, the conditions for incomplete stretching, twisting and false twist crimp processing, and the physical properties of the processed yarn. Comparing Test Nos. 1 to 6 in Table 1, it can be seen that twisting improves the strength of the processed yarn and improves its ability to pass through the process up to weaving.
This can also be seen in the case of undrawn yarns No. 6 to 7 with a birefringence index of 0.026.

【table】

[Table] Example 2 Semidull polyester fiber with birefringence index 0.026
An undrawn yarn of 295 denier and 48 filaments was twisted, then drawn as an incompletely drawn yarn, and then false twisted and crimped. This example has the same conditions as Test No. 7 of Example 1 except that the twisting order is reversed from the stretching order. The physical properties of the processed yarn obtained by this method were as follows. Strength of processed yarn (g/d) 3.87 Hair Feather 2 Process passability Very good dyeability The processed yarn has shading in the length direction, and the boundary between shading is more clear compared to test No. 7. Example 3 Incompletely drawn yarn of test No. 6 of Example 1 Semi-dull 173 denier, 48 filament, Semi-dull 150
Drawn polyester yarns of denier and 48 filaments were combined, then twisted and subjected to false twist crimp processing in a one-stage heater. The results are shown in Table 2. Test No. 31 is for the case where the twisting is zero and 2
It was extremely difficult to handle due to the lack of properties as a collection of book threads. On the other hand, the one with 300T/m plying had good convergence and was extremely easy to handle. In test No. 32 to 35, the number of false twists was changed by false twisting and crimping in the same direction after twisting. It is a processed yarn that is crimped, bulky, and has dark and light unevenness and untwisted parts. Here, when the number of twists during false twisting and heat setting is reduced for Test No. 32, the bulk due to crimping is reduced, and due to the floating fibers, a spun-like texture is observed (Test No. 33 , 34), and when the number of twists was further lowered, a silky texture was obtained (Test No. 35). test
When the heater temperature is set to 225℃ in No.33,
As in Test No. 36, the processed yarn became sticky and bunched, with many untwisted yarns. Adhesion appears in the dark dyed part of the incompletely drawn yarn, and due to partial adhesion, it is soft and has a soft linen touch even though it is bundled. The untwisted yarn common to test Nos. 32 to 36 had an eye wobbling and wrinkle effect, and perhaps because of this, the periodic patterning of the dark and light spots seemed to be slightly less. test
No. 37 was false-twisted and crimped in the opposite direction to the twisting direction, and was a stretchy textured yarn with many loop fibers and uneven density that was easy to handle.

【table】

Claims (1)

[Scope of Claims] 1 An incompletely drawn system in which an undrawn yarn made of a thermoplastic polymer is drawn at a draw ratio lower than the natural draw ratio so that thick fiber portions and thin fiber portions exist in each filament. 1. A method for producing textured yarn, which comprises subjecting the yarn to a stretching process and a heating process, followed by false twisting and crimp processing. 2. The manufacturing method according to claim 1, wherein the undrawn yarn is stretched and then twisted, and then false-twisted and crimped. 3. The manufacturing method according to claim 1, wherein the undrawn yarn is twisted and then stretched, and then false-twisted and crimped. 4. The manufacturing method according to claim 2, wherein the incompletely drawn yarn and the drawn yarn made of a thermoplastic polymer are heated and integrated, and then false-twisted and crimped. 5. The manufacturing method according to any one of claims 1 to 4, wherein false twisting and crimp processing is performed in the same direction as the twisting direction. 6. The manufacturing method according to any one of claims 1 to 4, wherein the false twisting and crimp processing is performed in a direction opposite to the heating direction.