JPH09111560A - Polyester-based low crimped textured yarn - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject low crimped textured yarn suitable as a yarn for woven and knitted fabric high in drape properties and excellent in elasticity. SOLUTION: This crimped textured yarn has a torque in which thick parts (a) and thin parts (b) are alternately formed in each filament constituting a polyester multifilament. The section change ratios of the thick parts (a) and the thin parts (b) are each <=1.3 and the physical properties of the crimped textured yarn satisfy the following items (1) to (3). (1) The elongation ratio by method C...<=10%, (2) elongation at break...50-100% and (3) thermal shrinkage stress...<=0.1g/d.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is suitable for obtaining a woven or knitted fabric having a high drape property and an excellent resilience property, which is composed of filaments having a thick portion and a fine portion alternately arranged in a longitudinal direction of a yarn. The present invention relates to a polyester low crimped yarn.

[0002]

2. Description of the Related Art Polyester multifilament yarn is
If weaved into a strong twisted yarn and processed at a high weight reduction rate, a fabric with drape and elasticity will be obtained, but for that purpose, advanced processing technology is required, and if ordinary raw yarn or processed yarn is used. However, it was not always possible to obtain a fabric having the above-mentioned texture even after performing strong twisting or weight reduction treatment.

Further, polyester yarns having orientation spots and thick spots are well known, and various manufacturing methods thereof have been proposed. For example, Japanese Patent Publication No. 2-29773 and Japanese Patent Publication No. 3-727.
Japanese Unexamined Patent Publication (Kokai) No. 30 discloses a thick and thin textured yarn obtained by subjecting a polyester highly oriented undrawn yarn to a relaxation heat treatment, followed by cold drawing, and then performing a spindle type false twisting process.

This thick and thin textured yarn has an irregular appearance and has a large difference in yarn length between constituent filaments, so that it has a bulky feel and a span-like feel such as a soft feel.
The drape was poor and the crimp had a high crimp, but the feeling was slimy and less elastic than the feeling with tension and waist. In addition, when twisted yarn or alkali weight reduction processing is performed to impart drapeability and elasticity to the processed yarn, the thick portion becomes fluffy in the twisting process, or thread breakage is induced. There was a problem such as becoming.

[0005]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned drawbacks of the conventional thick and thin textured yarns, imparts a high drape property to a fabric, excellent elasticity and an appropriate sharpness, and a post-process. It is a technical object to provide a polyester-based low crimped yarn having thick and thin spots in which fluff, yarn breakage, etc. do not easily occur.

[0006]

The present inventors have arrived at the present invention as a result of earnest research to solve the above-mentioned problems. That is, the present invention provides a crimped yarn having a torque in which thick portions and details are alternately formed in the longitudinal direction of each filament constituting a polyester multifilament yarn, and the cross-section change rate of the thick portions and details. Is less than 1.3, and the physical properties of the crimped yarn are as follows (1) to
(3) Formula (1) C method elongation rate 10% or less (2) Elongation at break 50 to 100% (3) Heat shrink stress 0.1 g / d or less Polyester low crimping process characterized by satisfying A thread is the gist.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

First, the polyester low-crimped yarn of the present invention is a yarn having a thick and thin shape in which thick portions and details are alternately provided in the longitudinal direction of each filament constituting the yarn.

In order to impart a natural mottled feeling to the fabric obtained from this yarn, it is preferable that the thick portions and details existing in the longitudinal direction of each filament are randomly dispersed.

Next, the cross-section change rates of the thick portion and the detailed portion are both 1.3 or less. When false twisting is performed with a spindle type or friction disc type twisted body, the cross-sectional change rate of the thick and thin processed yarn obtained from the circular cross-section yarn becomes more than 1.3 in the thick part, as shown in Fig. 3. The cross-sectional change rate is completely different from that of FIG. 2 showing the cross section of the textured yarn of the present invention. This is because in the case of false twisting with a spindle type or friction type twisted body, false twisting must be performed while stretching to some extent, and stable twisting is required unless the false twist coefficient is more than 20000. This is because the thick thin yarn is subjected to a high degree of twisting deformation, resulting in a yarn having a large cross-sectional change rate in the thick portion compared to the details.

Thus, as shown in FIG. 3, the conventional thick and thin textured yarns have greatly different cross-sectional shapes from the thick portion and the thin portion, and in the longitudinal direction of the filament, between the thick portion and the fine portion and from the fine portion to the thick portion. Since the cross-sectional shape changes greatly between the parts and is connected, fluff and thread breakage easily occur in this part due to pulling and ironing in the subsequent process.

On the other hand, the textured yarn of the present invention has a cross-section change rate of 1.3 or less in both the thick portion and the detail, and is a shape almost close to the cross-sectional shape of the supplied yarn. They are connected by a smooth shape without making an extreme change in shape, so that fluff and thread breakage do not occur due to external forces such as tension and ironing in the subsequent process.

Further, the textured yarn of the present invention has a C method elongation ratio.
It is less than 10%, so the crimp waveform is gentle and
It has a low crimping property that exhibits a smooth morphological change in the longitudinal direction of the yarn, forms a gentle wavy crimp, and bundles without forming an extreme difference in yarn length. The bundled low-crimped yarn has a shape close to a circle as a whole yarn and a torque due to a low-crimp crimped form. Therefore, compared with the conventional thick-thinned yarn, the drapability, elasticity, and sharpness are improved. The feeling is excellent. When the C-method elongation of the processed yarn exceeds 10%, the number of wavy crimps in the processed yarn increases, resulting in a highly crimped yarn, which emphasizes bulkiness and softness, and improves drape and elasticity. The texture will be lacking.

Next, the processed yarn of the present invention has a breaking elongation of 50 to 50.
It has 100% physical properties and a thermal shrinkage stress of 0.1 g / d or less. As described above, the processed yarn of the present invention is
As is clear from the fact that the elongation at break is a little high and the heat shrinkage stress is small, it is a yarn in an incompletely oriented state with intermediate orientation without being sufficiently drawn, In addition, since it has physical properties that are heavier than thick and thin processed yarns, it is particularly excellent in drapeability. Moreover, as described above, it has a thick and thin shape and has a so-called oriented uneven fiber structure, and the uneven shape and the cross-sectional shape close to the cross-section of the supplied yarn are mixed to give the yarn elasticity and crispness. To be done.

When the breaking elongation of the processed yarn is less than 50%, the thin and thin morphology of the yarn is reduced, the orientation of the yarn is increased, and the drape property and elasticity are lost. On the other hand, the breaking elongation is 1
If it exceeds 00%, the fabric is likely to be stretched in the post-process, and the morphology of the yarn changes, making it impossible to produce a fabric with stable quality.
Further, when the heat shrinkage stress exceeds 0.1 g / d, it is not preferable because the cloth shrinks due to shrinkage in the post-process such as dyeing after weaving and knitting, and the heat shrinkage stress is less likely to be deformed by heat. It is preferably 1 g / d or less, more preferably 0.02 to 0.09 g / d.

FIG. 1 is a schematic side view showing an embodiment of the polyester low-crimped yarn of the present invention, in which thick portions a and details b are randomly present in and between filaments constituting a yarn. However, it has a low-torque, gentle wavy crimp. As described above, the polyester low-crimped yarn of the present invention is provided with a gentle low crimp without substantially deforming the thick portion and the details, and has a yarn cross-section change rate.
Since the shape of 1.3 or less is maintained, no fluff or yarn breakage is generated by external force such as pulling or ironing in the subsequent process, and a gentle wavy crimp and weakness are formed in the longitudinal direction of the yarn. It is a processed yarn having elasticity and torque.

That is, the polyester low-crimped yarn of the present invention has thick and fine unevenness, its cross-sectional shape substantially maintains the cross-sectional shape of the supply yarn, and if it is a circular cross-sectional yarn, it is close to a circle, and is gentle. Since it has wavy crimps, has torque, has weak stretchability, etc., it has a high drape property and excellent elasticity and moderateness to the fabric obtained by weaving and knitting. It is possible to give a sharp feeling.

The polyester in the present invention is a generic name for polyesters having an ester bond in the molecular chain, which is represented by polyethylene terephthalate (PET), and is a group consisting of 5-sodium sulfoisophthalic acid, isophthalic acid, paraoxyethoxybenzoic acid and the like. A modified polyester containing three components may be used.

Next, an example of a method for producing the polyester low crimped yarn of the present invention will be described. Birefringence index (Δn)
20 × 10 ^-3 to 80 × 10 ^-3 polyester highly oriented undrawn yarn is used.
Relaxation heat treatment is performed under the conditions that the temperature is 300 to 700 ° C and the time for the yarn to pass through the non-contact heater is 0.01 to 0.15 seconds. Next, after cold drawing at a draw ratio at which thick and thin spots appear, for example, a ratio at which the yarn length contracted by the relaxation heat treatment returns to the original yarn length,
A fluid swirling nozzle is used as the twisted body, and the false twist coefficient K is 3000.
A false-twisted yarn having a low false-twist number of ˜15,000 is obtained to obtain an intended low-crimped yarn. The false twist coefficient K is K = false twist number (T / M) ×
(Fineness of supplied yarn: denier) ^1/2 . Further, after the false twisting process, a fluid entanglement treatment may be performed to impart a sizing property to the yarn.

FIG. 4 is a schematic process diagram showing an example of a method for producing the low crimped yarn of the present invention. In FIG. 4, the polyester highly oriented undrawn yarn 1 is subjected to relaxation heat treatment between the first feed roller 2 and the second feed roller 4 by the heater 3, and then the second feed roller 4 and the third feed roller 4. 5 is cold-drawn between 5 and 5 to form a yarn having thick and thin spots.

Next, the yarn having the thick and thin spots is twisted by the fluid swirling nozzle 8 between the third feed roller 5 and the first delivery roller 10, and is heat-fixed by the false twist heater 7 so as to be wound low. It becomes a crimped yarn. Subsequently, a mixed fiber entanglement process is performed by the fluid entanglement device 11 provided between the first delivery roller 10 and the second delivery roller 12, and then the second delivery roller 12 is passed through the second delivery roller 12 to wind the package 13. It is preferable that the false twisting of the thick thin yarn is performed at a low tension with a draw ratio of about 1.00 to 1.10 times. In order to stabilize the running of the yarn at the low tension, the upstream side of the false twist heater 7 and the fluid swirling nozzle are used. It is preferable to provide rotary roller guides 6 and 9 respectively on the downstream side of 8.

Each physical property in the present invention is obtained by the following method. (1) Cross-section change ratio The ratio of the diameter of the circumscribed circle of the monofilament that composes the processed yarn to the diameter of the inscribed circle is the ratio of the diameter of the circumscribed circle of the monofilament that composes the supply yarn to the diameter of the inscribed circle. It is the value divided by. (2) C method elongation rate and elongation at break It is measured according to JIS-L-1090 (textured yarn). (3) Thermal shrinkage stress It is measured by the following method using a thermal stress measuring instrument and a recording device linked to it. First, the sample is made into a ring of 5 cm using a sampling jig, then the thermal stress measuring device and the recording device are set to a temperature of 20 to 300 ° C. and a stress of 0 to 50 g, and the sample is placed above the thermal stress measuring device. And a hook at the bottom, apply an initial load of 1/10 g per denier, and then perform the measurement.
The heating rate is 300 ° C / 120 seconds. The measurement is performed 3 times, the stress (g) at the maximum stress point is read, and the heat shrinkage stress (g /
Calculated as d) = maximum stress (g) / fineness (denier) of the sample.

[0023]

EXAMPLES Next, the present invention will be specifically described based on examples.

Examples 1 to 3 and Comparative Examples 1 and 2 80d / 24f and 160f / 36f PET highly oriented undrawn yarns and cationic dyeable polyester highly oriented undrawn yarns 80d / 12f of 80d / 24f and 160f / 36f were used as the feeding yarns, and FIG. A low crimped yarn was manufactured under the conditions shown in Table 1 according to the steps shown in.

The textured yarns obtained in Examples 1 to 3 had a thick crimp and a detail randomly formed in the longitudinal direction of the yarn and had a low crimp form with a false twist coefficient of 6500 to 8800, and had a modified cross section. As shown in Fig. 1, the yarn had a gentle wavy crimp and torque. In particular, the processed yarn obtained in Example 3 had a heathered shape when dyed because the PET yarn and the cationic dyeable yarn were mixed.

These processed yarns are used for the warp and the weft, respectively, and have a warp density of 115 yarns / 2.54 cm and a weft yarn density of 75 yarns / 2.54 cm.
2/2 twill weave. In addition, Fukuhara company XL-
A PL2 (20G × 26 ″) knitting machine was used to knit a knitted fabric having a plain weave structure. The obtained woven fabric and knitted fabric were dyed and finished with a usual polyester prescription. The evaluation results of the obtained fabrics are shown in Table 1. Shown in.

[0027]

[Table 1]

As is apparent from Table 1, the fabrics obtained in Examples 1 to 3 all have high drapeability, excellent elasticity, and a feeling of sharpness. Met.

On the other hand, in Comparative Examples 1 and 2, the processed yarn had many fluffs, and the obtained fabrics were highly crimped and lacked in drapeability.

[0030]

The processed yarn of the present invention has thick and thin spots,
The cross-sectional shape is close to the cross-section of the supplied yarn, has a gentle wavy crimp, has torque, has weak stretchability, etc., so that the fabric obtained by weaving and knitting has high drape and excellent elasticity. It is also possible to impart a proper sharpness. Further, fluffing or yarn breakage does not occur due to external force such as ironing or pulling in the post-process such as additional twisting, weaving and weaving, and post-processing can be performed at high speed and stably.

[Brief description of the drawings]

FIG. 1 is a schematic side view showing an embodiment of a polyester-based low crimped yarn of the present invention.

FIG. 2 is a cross-sectional view showing an embodiment of the polyester low-crimp processed yarn of the present invention.

FIG. 3 is a cross-sectional view of a conventional thick and thin processed yarn.

FIG. 4 is a schematic process drawing showing an example of a method for producing a polyester low-crimp processed yarn of the present invention.

[Explanation of symbols] a thick part b thin part 1 polyester highly oriented undrawn yarn 3 heater 7 false twist heater 8 swirl nozzle 11 fluid entanglement device

Claims (1)

[Claims] 1. A crimped yarn having a torque in which a thick portion and a small portion are alternately formed in a longitudinal direction of each filament constituting a polyester multifilament yarn, and a cross-sectional change rate of the thick portion and the small portion is Both are 1.3 or less,
In addition, the polyester-based low crimped yarn, wherein the physical properties of the crimped yarn satisfy the following expressions (1) to (3). (1) C method elongation rate 10% or less (2) Elongation at break 50 to 100% (3) Heat shrinkage stress 0.1 g / d or less