JPS61194230A - Production of crimped processed yarn comprising multilayeredstructure - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is directed to a crimped yarn having a multilayer structure that has an appearance and texture similar to woolen yarn and does not shift during weaving and knitting. Regarding manufacturing methods.

<Prior art> Conventionally, the temporary crimped yarn obtained by false twisting thermoplastic synthetic fiber filament yarn is extremely bulky in the state of the processed yarn itself, that is, under micro tension close to zero tension. However, when it is made into a woven or knitted fabric, most of its bulkiness is lost. On the other hand, using two multifilament yarns with different elongations as a supply system,
There are also known crimped yarns that have a two-layer structure in which these are aligned and false-twisted, with high elongation multifilament yarns placed in the outer layer and low elongation multifilament yarns placed in the inner layer.
Even when such crimped yarn is subjected to tension during weaving and knitting, most of the tension is applied to the core yarn, and almost no tension is applied to the sheath yarn, so it forms a fabric while maintaining its bulkiness, giving it volume. On the other hand, since there is no entanglement between the core yarn and the sheath yarn, they easily shift due to slight strokes during weaving and knitting, and the weaving and knitting are performed with lumps scattered in the longitudinal direction. As a result, the resulting fabric has defects and may not be of practical use. Furthermore, in order to proactively eliminate the deviation caused by such straining, a processed yarn (Japanese Patent Application Laid-Open No. 1983-98931) has been proposed in which two multifilament yarns are pre-interlaced using an air entangling device. but.

The texture of such processed yarn is created by the formation of a large number of convergence points due to the entanglement process, which not only reduces the soft feel, voluminous feel, and sliminess, but also increases the processing cost due to the added cost of energy required for the entanglement process. It is inevitable that the rise in

<Problems to be Solved by the Invention> The present invention eliminates the drawbacks of the conventional crimped yarn as described above, and also increases the texture effect due to the bulkiness of the conventional crimped yarn having a two-layer structure. The technical object is to obtain a crimped yarn having a multilayer structure that does not shift even when subjected to ironing during weaving and knitting.

Means for Solving the Problems〉 That is, two features of the present invention are that the birefringence △n is 20 to 80X
A 10-' polyester highly oriented undrawn yarn is subjected to relaxation heat treatment, and the birefringence Δn of the relaxation heat-treated yarn is 20 to 8.
0x10-' polyester highly oriented undrawn yarns are aligned and false twisted.

The method of the present invention will be further explained in detail below.

First, in the second method of the present invention, the yarn to be subjected to relaxation heat treatment is a highly oriented undrawn polyester yarn having a birefringence Δn of 20 to 80×10 −′. In this case, it is necessary that the birefringence Δn of the highly oriented undrawn polyester yarn is 20 to 80X10-3, and if the birefringence Δn exceeds 80X10-', the amount of shrinkage during relaxation heat treatment is small and sufficient relaxation is achieved. Moreover, if the birefringence Δn is less than 20×10 − ”, the yarn becomes brittle and breaks during the false twisting process described later, resulting in poor operability, which is not preferable.

Similarly, for the other yarn that is not subjected to relaxation heat treatment, a highly oriented undrawn polyester yarn with a birefringence Δn of 20 to 80×10-” is used as the supply system.In this case, the birefringence Δn of the highly oriented undrawn polyester yarn is also used. is required to be 20 to so x to-3, and if the birefringence Δn exceeds 80 x 10-'', the amount of deformation due to torsional deformation during false twisting will be small, making it difficult to form a multilayer structure. Furthermore, the multilayer structure that is the object of the present invention can only be formed by providing a clear difference between the highly oriented undrawn polyester yarn that has been subjected to relaxation heat treatment and the highly oriented undrawn polyester yarn that has not been subjected to relaxation heat treatment.
When the birefringence Δn is less than 20×10 −2 , the elongation and softening point are close to those of the highly oriented undrawn polyester yarn subjected to relaxation heat treatment.

The yarn targeted by the present invention is difficult to obtain.

Note that if the same type of highly oriented undrawn polyester yarn is used as the yarn to be subjected to the relaxation heat treatment and the yarn to not be subjected to the relaxation heat treatment, the yarn type and process can be easily controlled.

In this way, on one side, the birefringence Δn is 20 to 80×10
By using a yarn obtained by subjecting the highly oriented undrawn polyester yarn of -2 to relaxation heat treatment, uneven shrinkage can be developed between the filaments, resulting in a yarn having crimped rings and uneven fineness.

This phenomenon is considered to be because the highly oriented undrawn polyester yarn has a partial internal strain in the longitudinal direction of the single filament.

In this way, when the highly oriented undrawn polyester yarn is made into a yarn with crimped rings and uneven fineness, it is pulled together with the other highly oriented undrawn polyester yarn and subjected to false twisting. The torsional deformation behavior during twisting becomes uneven, the filaments move in and out during torsional deformation between these yarns, and the false twist crimp is applied as it is, resulting in entanglement of the filaments, which is preferable due to slight entanglement. Conjugation properties are obtained. Here, mild entanglement refers to a state in which the crimped yarn consisting of two yarns does not shift during the weaving and weaving process including the preparation process, and specifically, it has a tearing tension of 5 g or more. be.

In this case, the tear tension is determined by sandwiching a crimped yarn with a core-sheath structure between the upper and lower clamps of a constant speed tensile tester. The tension of the compressed yarn is measured while separating it at a constant speed, and the maximum value of the tension at which the yarn is separated is referred to as the maximum value. If this tearing tension is less than 5 g, misalignment will occur during the ra knitting process. Said 2
If the threads of the book are too entangled, it will be difficult to create a bulky effect.

The degree of entanglement is preferably 100 g or less in terms of tearing tension.

When the highly oriented undrawn polyester yarn is subjected to relaxation heat treatment, the relaxation rate is preferably as high as 30% or more. If this relaxation rate is less than 30%, the crimp unevenness and fineness unevenness of the filament mentioned above will not be sufficiently obtained, and the interlacing property between both yarns will be reduced, and the yarn length will be sufficient between the core and sheath portions of the processed yarn. It is difficult to obtain the difference and crimp difference. Further, the relaxation heat treatment temperature is preferably 130 to 240°C, although it varies depending on the yarn speed. Note that the relaxation rate here is the ratio of the difference between the supply speed and the withdrawal speed to the withdrawal speed, expressed as a percentage.

Next, in the method of the present invention, the highly oriented undrawn polyester yarn that has been subjected to the relaxation heat treatment is aligned with the highly oriented undrawn polyester yarn that has not been subjected to the relaxation heat treatment and subjected to false twisting. In this case, the elongation of the highly oriented undrawn polyester yarn that has been subjected to the relaxation heat treatment increases its elongation and becomes a highly elongated yarn. Since large elongation differences and m-degree differences occur, the torsional deformation during false twisting causes different deformation behavior. In other words, since high elongation yarns elongate a lot when subjected to torsional deformation, they form an outer layer and become highly crimp, and within the high elongation yarn itself, elongation differences between the inner and outer layers occur even more when torsional deformation occurs, resulting in high crimp. Form a crimped part and a low crimped part. In addition, the low elongation yarn forms the inner layer portion because it elongates relatively little against torsional deformation. Furthermore, even within the low elongation yarn itself, a difference in elongation between the inner layer and the outer layer occurs due to torsional deformation, forming a high crimp portion and a low crimp portion. In this manner, unlike the conventional core-sheath two-layer structured yarn, the multi-layered structured yarn obtained by the method of the present invention exhibits a four-layer structure in which each core-sheath has a high crimp portion and a low crimp portion.

Therefore, it has an excellent sense of volume.

In the above-mentioned false-twisting process, in order to make the effect of the present invention more noticeable, it is preferable to perform false-twisting while stretching, and the stretching ratio during the stretching false-twisting process is d.

02-1, where d is the fineness (denier) of the highly oriented undrawn polyester yarn subjected to the relaxation heat treatment, d2 is the fineness (denier) of the highly oriented undrawn polyester yarn not subjected to the relaxation heat treatment, and α is the relaxation rate ( %), x is the stretching ratio. In this case, if the stretching ratio is less than 1.3, it is difficult to obtain a clear difference in fineness and crimp in the core-sheath part, and it is difficult to form a crimp difference in the sheath part, that is, a high crimp part and a low crimp part. This is not preferred, and the false twisting temperature is preferably 180 to 210°C.

As described above, since the method of the present invention performs processing with a low number of false twists, the degree to which the core of the sheath is wound is at most 10 twists.
It has a light alternating twist of ~100T/M (the sum of both S twist and Z twist), and unlike crimped yarn that is wound densely, it can fully contribute to the wool-like texture. . In this way, the processed yarn obtained by the method of the present invention has a multilayer structure in which both the core and sheath portions have a group of highly crimped filaments and a group of low crimped filaments.

FIG. 2 is a schematic side view showing an example of a crimped yarn having a multilayer structure obtained by the method of the present invention.9 In the yarn processed by the method of the present invention, as shown in FIG. The sheath part 04 is made up of a high crimp part a and a low crimp part, and a low crimp part Os.
It has a four-layer multilayer structure. And the sheath part 0@ is the core part (If
) is wound in an S twist, a B part in which the winding direction is reversed, and a sheath part 0 is wound in a core oat-z twist. It is longer than the part aυ and has a yarn length difference of at least 5%. Further, the sheath part 04) is wound in a state in which the entire sheath part 04) exhibits a crimped waveform compared to the core part Ql), and the filament groups of the core part Of) and the sheath part 04) are slightly intertwined.

Normally, the threads in a fabric are woven and woven under tension, so 2. Normally processed yarn cannot exist in a fabric while maintaining its crimped form, but 1. The tension is mainly maintained by the core Oo, and most of it is maintained by the low crimp part (1 m. Therefore,
The highly crimped part 0 of the core aυ, especially the highly crimped part a of the sheath part,
The low crimp part OeJ is made into the fabric with sufficient crimp.
Because it is woven in one piece, it becomes an extremely bulky fabric. In addition, the sheath part 0
4) is wound around the core part 01) in a slightly crimped waveform and has a difference in yarn length, so it exists as a walnut yarn. Therefore, it is possible to obtain a texture (slimy feel) very similar to that of wool spun yarn. Generally, it is said that the approximation of the texture of polyester filament yarn to the woolen yarn texture is due to the presence of a large amount of walnut yarn, which does not contribute to tension, in the filament yarn.

The present inventors used the coefficient of friction as one evaluation value for the texture of this woolen yarn. To explain the friction coefficient here, in the case of textiles, a sample of 10 cm in diameter x 10 cm in latitude is cut out and pasted on a thin flat plate, and a vertical load of 300 g is applied to the same cloth, which is fixed to another flat plate at a rate of 5 cm/sin.
Find the ratio of the movement resistance force and the above load when moving at a speed of . In other words, the friction coefficient in the warp direction is the resistance force (F
) divided by the load N (300 g in this case). In the case of the latitude direction, the value obtained when moving in the latitude direction is similarly expressed.

FIG. 3 is a chart showing the relationship between frictional resistance force and moving distance, and in FIG. 3 (Fυ indicates the initial resistance force.

(F2) represents a motion resistance force.9 In the present invention, the friction coefficient μ is determined by using this motion resistance force (F2) as a movement resistance force (F). Thus, the friction coefficient μ is given by μ=□. This friction coefficient depends on the fabric structure and weave density.

It varies depending on the dyeing and finishing method, etc., but in the case of ordinary false twisted yarn, the value is about 0.15 to 0.45, but in the yarn processed according to the present invention, the value is 0.7 to 1.3 in both the weft and weft directions. and values comparable to those obtained with wool fabrics (0.7-1.3) are obtained. Note that even in the case of ordinary false-twisted yarn fabrics, products that fall within the range of the friction coefficient of wool mentioned above can be obtained by special weaving methods, 2 textures, finishing methods, etc., but these are only in the warp direction or in the weft direction. However, the processed yarn according to the present invention does not satisfy both the texture and process at the same time.As mentioned above, the effect of the processed yarn according to the method of the present invention is as follows: This is because both the sheath (example) has a low crimp part and a high crimp part, and is present in the fabric as a walnut thread that has sufficiently developed a crimp waveform.
Therefore, a tactile sensation extremely similar to that of wool spun yarn and a large voluminous feel can be obtained. Also.

The processed yarn according to the method of the present invention has a sheath part (141 is a core part (Ill)
While winding the surrounding area, the filaments in the highly crimped part 0!9 of the sheath part (example) and the highly crimped part 0! of the core part 01) are intertwined with each other.

It does not shift even when subjected to ironing during weaving and knitting.

Misalignment of yarn exhibiting a core-sheath structure during weaving and knitting is likely to occur when the tearing tension of the yarn is less than 5 g; however, in the case of yarn processed by the method of the present invention, the tearing tension is 5 g or more, and when weaving and knitting, No deviation occurs. Thus, by using the processed yarn according to the method of the present invention, it is possible to obtain a fabric that is very similar to wool spun yarn in terms of sliminess and volume.

FIG. 1 is a process schematic diagram showing an example of the manufacturing process of the method of the present invention, in which the yarn (Yl) pulled out from the highly oriented polyester undrawn yarn spool (1) is fed through the feed roller (3). The yarn (2) is subjected to a relaxing heat treatment by a heater (4) between the roller (3) and the first delivery roller (5), and then pulled out from the highly oriented polyester undrawn yarn spool (2) by the first delivery roller (5). Y
z), are stretched between the first delivery roller (5) and the second delivery roller (8) via the first delivery roller (5), and are simultaneously heated by the false twist spindle (7) and heated by the heater (6). ), and then passed through a second delivery roller (8) and rolled up into a package α by a winding roller (9). In addition, the second delivery roller (8
) and the take-up roller (9) to perform further heat treatment to reduce the false twisting torque and improve the crimp form. The connection between the rows (Y+) and (Y2) can be further strengthened. In the present invention, it is preferable to carry out the relaxation heat treatment and the false twisting process continuously, but they may of course be carried out separately.

The polyester in the present invention is a polymer having an ester bond in one molecule chain, and includes homopolymers typified by polyethylene terephthalate, copolymers or blend polymers thereof, and the like. Further, the birefringence Δn was measured by an interference fringe measurement method using a polarizing microscope-compensator.

<Example> The present invention will be specifically described below based on nine examples.

Example Highly oriented undrawn polyester yarn 110d/36f (circular cross-section yarn) with a birefringence Δn of 51 x 10-'' obtained by high-speed spinning of polyethylene terephthalate was given a relaxation rate of 40.
%, yarn subjected to relaxation heat treatment at a temperature of 165°C and birefringence △n
Highly oriented undrawn polyester yarn 1 with a diameter of 51 x 10-'
10d/36f (circular cross-section yarn) was used as a supply system according to the process shown in Figure 1, and stretched and false-twisted at a draw ratio of 1.553°, a false twist number of 1900 T/M, and a false-twisting temperature of 185°C. Application 3 A crimped yarn having a multilayer structure was obtained by the method of the present invention.

The obtained crimped yarn had a core-sheath structure, with a yarn length difference of 7.1% between the core and sheath, and a four-layer structure with a crimp difference in both the core and sheath. It was a crimped yarn. The four-layer structure was confirmed by separating the crimped yarn into a core and a sheath, elongating each by 8%, and finding that each was divided into a high crimp state and a low crimp state. .

In addition, when observing any cross section of this crimped yarn, it is found that it has a relatively circular shape, a pentagonal shape due to false twisting, and a 6-sided shape due to false twisting.
The cross-sectional shapes were a mixture of angular and flattened shapes.

This crimped yarn was woven into a 272-fill structure with a warp density of 84 threads/inch and a weft density of 73 threads/inch, and was subjected to the same dyeing and finishing treatment as ordinary polyester filament yarn.
Tactile sensation (slimy feeling), volume.

The soft feel and other textures were similar to those of fabrics made from wool spun yarn.

<Effects of the Invention> As described above, the method of the present invention applies relaxation heat treatment to highly oriented polyester undrawn yarn to give high extensibility and crimp, and highly oriented polyester undrawn yarn that is not subjected to relaxation heat treatment. Since the method of the present invention uses a specific supply system to align these filaments and perform false twisting, the method of the present invention causes uneven false twisting to occur between the filaments during the false twisting process, resulting in entanglement between the filaments. A crimped yarn can be produced in which a core-sheath structure is formed by the difference in elongation, and the core and sheath parts have a multilayer structure consisting of filament groups in high-crimp areas and low-crimp areas, respectively. . Therefore, the crimped yarn according to the present invention provides a slimy feel that cannot be obtained with conventional crimped yarns.

A wool-like yarn-like fabric with excellent volume and the like can be obtained. Moreover, although the crimped yarn obtained by the method of the present invention has a multilayer structure, the core and sheath portions are slightly intertwined by utilizing the crimp unevenness and fineness unevenness obtained by relaxation heat treatment. Because of this, there is no deviation in ironing during I1 knitting, which occurs in conventional crimped yarns with a core-sheath structure. Furthermore, according to the method of the present invention, there is no need for prior interlacing treatment using an interlacing device.

The volume and sliminess caused by the entangling treatment are not diminished, and the processing cost can be reduced compared to a manufacturing method using an entangling device.

[Brief explanation of drawings]

Fig. 1 is a process schematic diagram showing an example of the manufacturing process of the method of the present invention, Fig. 2 is a side schematic diagram showing an example of a crimped yarn obtained by the method of the present invention, and Fig. 3 is a diagram showing the frictional resistance of the fabric. It is a chart showing the relationship with moving distance. (1), (2L-m-polyester highly oriented undrawn yarn spool. (3) --- feed roller, (4)... heater,
(5)-first pre-heli roller, (6)-heater, (7
)...-false twisting spindle. (8) - second delivery roller, (9) - winding up roller,
αω-package, 01l-core, a-ku--high crimp in the core, aS...-low crimp in the core,
(+41-Sheath part, (1'!-High crimp part in the sheath part, 019.-Low crimp part in the sheath part.

Claims (1)

[Claims] 1. A highly oriented undrawn polyester yarn with a birefringence Δn of 20 to 80×10^-^3 is subjected to relaxation heat treatment, and the relaxation heat-treated yarn has a birefringence Δn of 20 to 80. ×10^-^3
A method for producing a crimped yarn having a multilayer structure, which comprises aligning and false twisting highly oriented undrawn polyester yarn. 2. A method for producing a crimped yarn having a multilayer structure according to claim 1, wherein the relaxation rate during relaxation heat treatment is 30% or more.