JP3244150B2 - Manufacturing method of polyester heather-like thick and thin yarn - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a thick polyester yarn.

[0002]

2. Description of the Related Art Thick and thin yarns, i.e., thick and thin yarns whose fineness changes in the longitudinal direction of a single fiber are so-called partially heterogeneous shrinkage mixed yarns. It has a texture, and especially the dyeing produces a mixed tone due to the difference in shading between the thick part and details of the single fiber. In general, thick and thin yarns vary from slab-like to marbling-like depending on the length, number and dispersion state of the thick part of the single fiber, but slab-like thick and thin yarn has a strong contrast of light and shade,
The thick portion is large and the dispersion pattern is coarse, while the marbling thick yarn is, for example, disclosed in Japanese Patent Application No. 4-37717.
No., the polyester unstretched yarn is stretched at a low magnification simultaneously with heating at a relatively low temperature, and the total stretching ratio is MDR ×
(0.45 to 0.55), it has been proposed to obtain a thick and thin thread in which the thick part and the details are highly dispersed by additionally stretching to obtain (0.45 to 0.55). However, there is a problem that the contrast is weak because the dispersion is too random.

[0003]

SUMMARY OF THE INVENTION The present invention solves the problem of such conventional thick and thin yarns, particularly the thick and thin yarns proposed in Japanese Patent Application No. Hei 4-37717, and provides a strong contrast in the dyeing. Another object of the present invention is to obtain a polyester thick and fine yarn having a dense and random dispersion of thick portions and details.

[0004]

According to the present invention, a birefringence of 1 is provided.
An unentangled polyester yarn having a size of 5 × 10 ⁻³ to 40 × 10 ⁻³ is air-entangled under a constant tension to obtain 30 to 150 yarns / m 3.
And then continuously stretching in two steps under the conditions satisfying the following formulas (1) to (5). (1) TDR = MDR × (0.45 to 0.55) (2) TDR = DR ₁ × DR ₂ (3) DR ₁ = MDR × (0.40 to 0.50) (4) HRT ≦ Tc ( 5) Tg ≦ HPT ≦ Tc where TDR is the total draw ratio, DR ₁ is the first draw ratio, DR ₂ is the second draw ratio, MDR is the maximum draw ratio of the undrawn yarn, and HRT is the first draw ratio. The temperature (° C.) in the first-stage stretching, the HPT is the temperature (° C.) in the second-stage stretching zone, T
c is the crystallization temperature (° C.) of the undrawn yarn, and Tg is the glass transition temperature (° C.) of the undrawn yarn.

In the present invention, the polyester undrawn yarn used is made of a polyester whose main repeating unit is ethylene terephthalate and has a birefringence of 15 × 10
It is necessary to use a polyester undrawn yarn of ^-3 to 40 × 10 ^-3 as a supply yarn. Birefringence is 15 × 1
When it is less than 0 ^-3 , not only the thick portion (unstretched portion) becomes too long in the first-stage stretching region employing a low stretching ratio, but also the thick portion is subjected to heat treatment such as false twisting and dyeing. When it is embrittled by alkali treatment, processing stability and quality are impaired, and when the birefringence exceeds 40 × 10 ⁻³ , the difference in shrinkage between the thick part and the small part is small, and the swelling is lacking.

In the present invention, in order to enhance the contrast of light and thick yarns in dyeing, the polyester undrawn yarn is air-entangled under a constant tension to obtain 30 to 150 yarns.
m, preferably 50 to 120 entanglements / m.
The entanglement is to prevent knots from being formed between the filaments so that the drawing points are not randomly generated in each filament. Localization. When the confounding is less than 30 filaments / m, the dispersion of the thick part and the details between the filaments becomes too dense, and the contrast of the light and shade is weak. When it exceeds 150 filaments / m, the dispersion of the thick part and the details between the filaments becomes impossible.

The air entanglement treatment needs to be performed under a constant tension, and the yarn tension immediately before reaching the air entanglement device is a constant tension selected from the range of 0.01 to 0.05 g / d. Carrying out is preferable in terms of running stability of the yarn and formation of entanglement. When the yarn tension fluctuates, the dispersion pattern of the thick part and the fine part fluctuates, and a fabric having good dyeing quality cannot be obtained. An appropriate air pressure is 1 to 3 kg / cm ² , and any device such as a parallel plate type or a cylinder type as shown in FIGS. 3A and 3B is used as an air entanglement device.

Next, in the present invention, the air-entangled undrawn yarn is formed by dispersing the thick portion and the details.
It is stretched in two steps. The heating temperature in the first-stage drawing is equal to or lower than the crystallization temperature of the undrawn yarn, and the draw ratio DR ₁ is MDR ×
(0.40 to 0.50) and stretch. Since the utilization of MDR varies depending on the difference in the birefringence of the undrawn yarn used, it is preferable to set the residual elongation of the thick and thin yarn obtained by the first-stage drawing to be 70 to 110%. . The thick and thin yarn obtained by the first-stage drawing has a relatively long thick portion, a high elongation and a high shrinkage, and a large difference in fineness between the thick portion and the details.

The thick and thin yarn obtained in the first-stage drawing is subjected to the second-stage drawing and the total drawing ratio TDR is MDR × (0.45 to 0.5
5) and a draw ratio add stretching in DR _2, the heat treatment at the second stage or above the glass transition temperature was set to provide a shrinkage of interest at a stretching zone the crystallization temperature or lower. By this second-stage stretching, a thick heat-and-thin yarn in which the contrast between dyeings is strong and the thick part and details are short and randomly dispersed is obtained.

[0010]

The present invention will be described below in more detail with reference to examples. The measurement items were based on the following method. The number of entangled air: The number of entangled undrawn yarns is the number of entangled drawn yarns determined by the Ross Pull / Celanese needle pull tester R-2.
040, and a numerical value obtained by multiplying by the stretching ratio.

(Examples 1-3, Comparative Examples 1-3) Polyethylene terephthalate containing 0.5% by weight of titanium oxide and having an intrinsic viscosity of 0.65 was spun at a spinning temperature of 72 using a spinning nozzle having 72 holes having a diameter of 0.2 mm. 290 ° C, winding speed 1700
The yarn was spun at m / min to obtain an undrawn yarn of 180d / 72f.
The obtained undrawn yarn had a glass transition temperature of 72 ° C. measured by dilatometry, a crystallization temperature of 129 ° C. measured by a scanning calorimeter, and a birefringence of 31 × 10 ⁻³ . This unstretched yarn has an overfeed rate of 0.5 to 1.0%,
Yarn tension of 2-4 g (0.01-0. 0 g) just before the air entanglement device.
Air entanglement treatment using an air entanglement device shown in FIG. 3A under the conditions of 02 g / d) and an air pressure of 1 to 3 kg / cm ² , and then a first draw ratio of 1.494 times and a temperature of 110 ° C.
Step stretching, followed by a stretching ratio of 1.015 times and a temperature of 12
The second stage of stretching and simultaneous heat treatment at 0 ° C. was performed to obtain a thick and thin yarn. Table 1 shows the quality of the obtained thick and thin yarns. Comparative Examples 1 to
Table 1 also shows the yarn quality of the thick and thin yarn obtained as No. 3 outside the conditions of the present invention. The fineness unevenness chart of the thick and thin yarn obtained in Example 2 is shown in FIG. 1, and the fineness unevenness chart of the thick and thin yarn obtained in Comparative Example 3 is shown in FIG.

[0012]

[Table 1]

(Examples 5 to 8 and Comparative Example 4) Polyethylene terephthalate containing 0.5% by weight of titanium oxide and having an intrinsic viscosity of 0.65 was spun through a 36-hole triangular cross-section spinning nozzle at a spinning temperature of 290 ° C. and a winding speed of 1800 m. / Minute spinning at 11
An undrawn yarn of 5d / 36f was obtained. The obtained undrawn yarn is
Glass transition temperature of 72 measured by dilatometry
C., the crystallization temperature measured by a scanning calorimeter was 129 ° C., and the birefringence was 31 × 10 ⁻³ . The undrawn yarn is supplied with an overfeed rate of 0.5 to 1.0% and a yarn tension of 1.5 to 2.5 g (0.01 to 0.02 g /
d), FIG. 3 (a) under the condition of air pressure of 1 to 3 kg / cm ²
Air entanglement treatment using an air entanglement device shown in the following, then stretched at a stretching ratio of 1.480 times, at a temperature of 95 ° C. in the first stage,
Subsequently, a second step of stretching and simultaneous heat treatment at a stretching ratio of 1.115 and a temperature of 120 ° C. was performed to obtain a thick and thin yarn. Table 2 shows the quality of the obtained thick and thin yarns. Table 2 also shows, as Comparative Example 4, the quality of the thick and thin yarn obtained outside the conditions of the present invention.

[0014]

[Table 2]

[0015]

According to the present invention, by applying air confounding, excessive dispersion of thick portions and details is suppressed, so that the thick portions and details are suitable for expressing clothing having a casual appearance, and the shading of the details is dyed. The contrast is strong, and the dispersion of the thick part and the details is dense, and it is possible to stably obtain a random heather-like thick thread,
It is possible to provide a thick and thin thread different from the conventional marbled and thick slab-like thick and thin threads.

[Brief description of the drawings]

FIG. 1 is a chart of fineness unevenness chart of thick and thin yarn obtained in Example 2.

FIG. 2 is a chart of fineness unevenness chart of a thick and thin yarn obtained in Comparative Example 3.

FIG. 3 is a side view and a plan view of an example of an air entanglement device that can be used in the present invention.

[Explanation of symbols]

 a Parallel plate type b Cylinder type

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI D02J 1/00 D02J 1/00 L (56) References JP-A-1-148823 (JP, A) JP-A-62-133118 ( JP, A) JP-A-57-193539 (JP, A) JP-A-3-241024 (JP, A) JP-A-64-26748 (JP, A) JP-A-63-121318 (JP, A) JP-A-62-41342 (JP, A) JP-A-59-9121 (JP, A) JP-A-61-146836 (JP, A) JP-A-60-194115 (JP, A) (58) Fields investigated (Int) .Cl. ⁷ , DB name) D02J 1/00-1/22 D01F 6/62 D02G 3/00-3/48

Claims (1)

(57) [Claims] 1. A birefringence of 15 × 10 ⁻³ to 40 × 10 ^−3.
The polyester unstretched yarn is air entangled under constant tension to give 30 to 150 entangled yarns / m, followed by two-stage drawing under the conditions satisfying the following formulas (1) to (5). Characteristic method of producing polyester heather-like thick and thin yarn. (1) TDR = MDR × (0.45 to 0.55) (2) TDR = DR ₁ × DR ₂ (3) DR ₁ = MDR × (0.40 to 0.50) (4) HRT ≦ Tc ( 5) Tg ≦ HPT ≦ Tc where TDR is the total draw ratio, DR ₁ is the first draw ratio, DR ₂ is the second draw ratio, MDR is the maximum draw ratio of the undrawn yarn, and HRT is the first draw ratio. The temperature (° C.) in the first-stage stretching, the HPT is the temperature (° C.) in the second-stage stretching zone, T
c is the crystallization temperature (° C.) of the undrawn yarn, and Tg is the glass transition temperature (° C.) of the undrawn yarn.