JPH1060744A - Partly fused false-twist textured yarn and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a hemp-tone partially-fused false-twisted yarn having a sufficient spot feeling rich in surface changes, exhibiting an appropriate sharpness and a soft texture. SOLUTION: By intermittently drawing false twisting a highly oriented undrawn yarn under specific conditions, a fused and bundled portion having a real twist in the yarn longitudinal direction and a crimped single fiber exist in a state of being separated. A multifilament yarn in which there is a mixed portion in which the fused bundle portion and the fused bundle portion are mixed and integrated, and the sum of the fused bundle portion and the mixed portion in the longitudinal direction of the yarn. The occupation ratio is 35% to 90% with respect to the entire yarn, and the length of the mixed portion is 8 mm or less. And 3% to 20% of the partially fused false twisted yarn with respect to the sum of

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a partially-fused false-twisted yarn suitable for obtaining a hemp-like knitted fabric having a mottled feeling and exhibiting an appropriate sharpness and softness, and a method for producing the same. It is.

[0002]

2. Description of the Related Art Conventionally, as a method of obtaining a yarn having a spun like property and a hemp-like sharpness, a so-called fusion-bonded yarn in which filaments are melt-bonded to each other has been known.
Many suggestions have been made. When the degree of fusion is increased, such a fusion-processed yarn has a crisp feeling, but on the other hand, has a hard feel and a rough feel. Also, when the false twist temperature is lowered to lower the degree of fusion, a soft feeling can be obtained, but not only the spot feeling is inferior, but also the sharpness is lowered and the product becomes inferior. That is, adjustment of the degree of fusion is important.

[0003] In order to solve the above-mentioned problems,
There has been proposed a method for producing a processed yarn comprising a thermoplastic multifilament yarn and having a fused portion and a spread portion in the longitudinal direction of the yarn. For example, in Japanese Patent Publication No. 51-42662,
A method has been proposed in which, after performing the fusion false twisting, tension is applied by applying tension. Japanese Patent Application Laid-Open No. 7-15793
No. 1 proposes a method in which two types of polyester high-orientation undrawn yarns having different melting points are used and a draw false twisting process is performed while a part of the low-melting-point yarn is fused. However, even if the processed yarn obtained by such a method is set to a ratio of the fused portion / crimped portion having a sufficient spot feeling, a sharp feeling of the fused portion is too strong and a soft texture can be obtained. Was difficult. Further, Japanese Patent Application Laid-Open No. H8-100340 proposes a method of obtaining a partially opened fused yarn by providing a bending guide on the outlet side of the false twist device. However, even with such a method, although a processed yarn having a soft feeling without a rough feeling of the fused yarn can be obtained, a knitted fabric having a mottled feeling aimed at by the present invention could not be obtained.

[0004]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned drawbacks, and has a hemp-like partially fused false twist which has a sufficient sensation rich in surface changes, exhibits an appropriate sharpness and a soft texture. It is an object to provide a processed yarn and a method for producing the processed yarn.

[0005]

The partially fused false twisted yarn of the present invention has the following structure to solve the above-mentioned problems.
That is, the present invention provides a fused bundle having a real twist in the longitudinal direction of the yarn, a spread portion having a crimped single fiber that is present in a separated state, and a mixture of the fused bundle and the spread portion. A multifilament yarn having an integrated mixed portion, wherein the occupation ratio of the sum of the fusion bunched portion and the mixed portion in the yarn longitudinal direction is 35% to 90% with respect to the entire yarn. And the length of the mixed portion is 8 mm or less, and the occupancy of the mixed portion in the longitudinal direction of the yarn is 3% to 20% with respect to the sum of the fused bundle portion and the mixed portion. The partially fused false twisted yarn to be formed is a first gist.

[0006] A second aspect of the present invention, a method for producing a partially fused false twisted yarn, has the following configuration. That is, a polyester highly oriented unstretched yarn having a birefringence Δn of 20 × 10 −3 to 70 × 10 −3 was obtained by stretching at a draw ratio DR1 satisfying the following formulas (a) and (b) at a temperature of 60 to 135 ° C. Outdraw stretching, followed by stretching ratio DR2, false twist temperature 200-2
This is a method for producing a partially-fused false-twisted yarn, wherein interdrawing is performed intermittently by intermittently releasing the grip of a feed roller when performing false-twisting at 40 ° C. NDR × 0.6 ≦ DR1 ≦ NDR × 0.9 (B) NDR × 0.7 ≦ DR1 × DR2 ≦ NDR × 1.0 (B) (However, NDR represents a natural stretching ratio) Here, at the time of outdraw stretching, the surface temperature is 60 ° C to 1 ° C.
It is preferable to use a pin heater at 20 ° C.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. FIG. 1 shows an embodiment of the partially fused false twisted yarn of the present invention. In FIG. 1, the fusion converged portion A is formed by fusing the unstretched portion remaining during outdraw stretching, and is a portion mainly exhibiting a hemp-like sharpness. The portion C has a crimp given by the formula (1) and exhibits a soft feeling, and a portion C indicates a mixed portion in which the fusion converged portion A and the spread portion B are mixed.

[0008] The sum of the fusion bunched portion A and the mixed portion C of the partially fused false twisted yarn of the present invention must occupy 35% to 90% of the entire yarn. This occupancy is determined by the ratio in the longitudinal direction of the yarn, and is more preferably 45% to 80%.
%. When the ratio of the sum of the fused and converged portion A and the mixed portion C is less than 35% of the entire yarn, it is difficult to exhibit a hemp-like sharpness, and when it exceeds 90%, not only is the softness inferior. , Resulting in poor surface change.

In the fusion-bundled portion A and the mixed portion C of the partially-fused false-twisted yarn of the present invention, there is a portion having a twist in the direction of false-twist twisted and bundled. The mixed portion C provides an appropriate sharpness and softness. The length of the longest continuous mixed portion is 8 mm or less, and the occupancy of the mixed portion C is 3% to 20% of the sum of the fusion convergence portion A and the mixed portion C. When the mixed portion exceeds 8 mm, not only the sharpness is reduced, but also the difference in the apparent thickness between the fused bundle portion A and the spread portion B having crimps is reduced, and the spot feeling is inferior. . Preferably, the apparent diameter of the fused bundle portion A is 0.3 to 0.8 of the apparent diameter of the spread portion B. Furthermore, the occupation rate of the mixed portion C is 3
If it is less than%, the feeling of crush is too strong and inferior to soft feeling,
On the other hand, if it exceeds 20%, the crispness is reduced, and it is difficult to obtain a knitted fabric aimed at by the present invention.

Next, a method for producing a partially fused false twisted yarn will be described. FIG. 2 is a schematic process diagram showing an example of a method for producing the yarn of the present invention. In FIG. 2, the birefringence index Δn is 20 × 10
^-3 to 70 × 10 ^-3 polyester highly oriented unstretched yarn 1 is supplied from a supply roller 2 and subjected to outdraw stretching between the feed roller 2 and the feed roller 4 under a condition satisfying the following formula (A). , Then during outdraw stretching,
Stretch false twist is performed at a temperature at which the remaining unstretched portion causes fusion. NDR × 0.6 ≦ DR1 ≦ NDR × 0.9 (A) (DR: stretch ratio of outdraw, NDR: natural stretch ratio)

At this time, the partially fused false twisted yarn of the present invention can be obtained by intermittently releasing the grip of the feed roller 4. In a state where the feed roller 4 is gripped, after drawing into a so-called thick and thin yarn by outdraw drawing, draw false twist is performed at 200 to 240 ° C.
At this time, the thick portion, which is a non-stretched portion, which is mixed, is fused to form a yarn shape like the bundle portion A. In a state where the grip of the feed roller 4 is released, the operation is the same as that of the normal draw false twist, and a yarn form such as the spread portion B is obtained. Also, the mixed part C
Is considered to be a transient phenomenon of the action for producing the converging portion A and the spread portion B. That is, by controlling the gripping of the feed roller 4, the converging section A, the opening section B and the mixing section C are controlled.
Can be adjusted. As a method of controlling the release time of the grip of the feed roller, a method of intermittently nipping the feed roller itself, a method of using a deformable roller such as a grooved roller, or the like can be used.

In the present invention, the birefringence Δn is 20 × 1
It is important to use a polyester highly oriented undrawn yarn of 0 ^-3 to 70 × 10 ^-3 . The cross section of the polyester highly oriented unstretched yarn to be used is not particularly limited, and a yarn having an irregular cross section such as a cross section having a similar degree of orientation and a Y section may be used. If the birefringence Δn is smaller than 20 × 10 ⁻³ , thermal degradation of the unstretched portion proceeds, and workability becomes unstable during false twisting. On the other hand, the birefringence Δn is 70 × 10
^{If it is} larger than ^-3, the orientation of the thick part of the thick and thin yarn formed by outdraw drawing increases, making it difficult for fusion to occur, and at a temperature at which fusion is possible, the entire yarn is deteriorated and the yarn strength is reduced. Would. Further, since the degree of fusion of the converging portion becomes low, it becomes impossible to obtain a sufficient sharp feeling.

The conditions for outdraw stretching between the feed rollers 2 and 4 are as follows: the stretching ratio is (NDR × 0.6) to (NDR).
DR × 0.9) (however, NDR: natural stretch ratio). More preferably, (NDR x 0.70)-
(NDR × 0.85). When the draw ratio of the outdraw stretching is less than (NDR × 0.6), the ratio of the thick portion is high and the formation of the spread portion and the mixed portion is reduced, resulting in a rough knitted fabric with insufficient softness. On the other hand, when the draw ratio of the outdraw stretching exceeds (NDR × 0.9), the proportion of the thick portion becomes low due to the stretching, and the sharpness is reduced. At the time of outdraw stretching between the feed rollers 2 and 4, the surface temperature is set to 60 ° C to 135 ° C, preferably 60 ° C to 120 ° C for the purpose of lowering the stretching tension in order to prevent damage to the rollers.
Is used. If the surface temperature exceeds 135 ° C., the orientation of the thick part is advanced and the degree of fusion becomes low, and it becomes difficult to obtain a hemp-like sharp feeling. 60 ° C
If it is less than 1, the plasticization of the yarn does not proceed and the tension does not decrease.

In the stretching false twisting step after the outdraw stretching, the stretching ratio must satisfy the condition of the following formula (b). NDR × 0.7 ≦ DR1 × DR2 ≦ NDR × 1.0 (B) However, DR1 represents an outdraw stretch ratio, DR2 represents a false twist stretch ratio, and NDR represents a natural stretch ratio. The product of the outdraw draw ratio and the draw ratio during false twist is NDR x 0.7
If it is less than 1, the processability such as ballooning during false twisting will be poor, and if it exceeds NDR × 1.0, the unstretched portion will be reduced, making it difficult for fusion to occur, making it difficult to obtain a sharp feeling.

The temperature of the heater at the time of false twisting is determined by the degree of orientation of the yarn used and the draw ratio at the time of processing, and is not particularly limited, but generally about 200 to 240 ° C. is preferable. In addition, the type of false twist is not particularly limited, and may be a commonly used false twist device such as a pin type, a friction type, or a belt nip.
It is only necessary that the crimp be stably provided by the false twisting step.

[0016]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. Natural stretching ratio in Examples and Comparative Examples,
The occupancy of the converging portion A and the occupancy of the mixed portion C were measured by the following methods.

<Natural stretching ratio> A strong elongation curve (SS curve) as shown in FIG. 3 is taken in a room at 20 ° C. × 65% RH.
The natural stretching ratio was measured.

<Occupancy> The occupancy of the converging portion A and the mixed portion C is determined by applying a load of 0.005 g / d to a sample of about 30 cm, and setting the lengths LA and LC of the converging portion A and the mixed portion C to 20 respectively. The measurement was performed twice, and the average value was used to calculate according to the following equation. The occupancy of the sum of the focusing portion A and the mixing portion C = (LA + LC) /
L × 100 (%) The occupancy of the mixed portion C was calculated by the following equation. Occupancy rate of mixed portion C = LC / (LA + LC) × 100
(%)

(Examples 1 to 4, Comparative Examples 1 to 4) An LS-6 false twisting machine table manufactured by Mitsubishi Heavy Industries, Ltd. was used as a processing machine table.
A 0 denier / 36 filament polyethylene terephthalate highly oriented undrawn yarn (birefringence: 52 × 10 −3, natural drawing ratio: 1.43) was used as the supply yarn, and the winding speed was 10%.
0m / min, heater temperature 230 ° C, number of false twists 3000T /
At M, according to the process of FIG. 2, outdraw stretching and stretch false twisting were continuously performed. Table 1 shows the processing conditions at this time. Here, the holding time of the feed roller 4 is 0.24.
Seconds and the release time of the roller was 0.15 seconds. A circular knitted fabric was knitted using the processed yarn obtained at this time, and the texture was evaluated. Table 1 shows the results.

[0020]

[Table 1]

(Examples 5 to 7 and Comparative Example 5) In the same manner as in Example 1, at the time of outdraw stretching, processing was performed under the conditions shown in Table 2 using a pin heater. Table 2 shows the results.
Shown in

[0022]

[Table 2]

(Comparative Example 6) As in Example 1, 10
A 0 denier 48 filament polyethylene terephthalate highly oriented undrawn yarn (birefringence: 86 × 10 −3, natural drawing ratio: 1.32) was wound at a winding speed of 100 m / min, a heater temperature of 230 ° C., and a number of false twists of 3,000 T /. At M, according to the process of FIG. 2, outdraw stretching and stretch false twisting were continuously performed. At this time, the holding time of the feed roller 4 is 0.
24 seconds, the release time of the roller was 0.15 seconds.
The length of the continuous mixed portion of the obtained yarn was 15 mm, and the ratio thereof was 30%.

[0024]

The partially-fused false twisted yarn of the present invention can exhibit a knitted fabric excellent in spotting mainly due to the bundled portion and the spread portion, and having an appropriate sharpness and softness. . Further, according to the production method of the present invention, such a partially fused false twisted yarn can be stably obtained.

[0025]

[Brief description of the drawings]

FIG. 1 is an external view showing an embodiment of a partially fused false twisted yarn of the present invention.

FIG. 2 is a schematic process chart showing one embodiment of a method for producing a partially fused false twisted yarn of the present invention.

FIG. 3 shows a high elongation curve of a highly oriented polyethylene terephthalate yarn.

[Explanation of Symbols] A Converging part B Crimped part C Mixed part 1 Polyethylene terephthalate highly oriented undrawn yarn 2 First feed roller 3 Pin heater 4 Second feed roller 5 First heater 6 False twist device 7 First delivery roller 8 Second heater 9 Second delivery roller 10 Winder

Claims (3)

[Claims] 1. A fused bundle portion having a real twist in the longitudinal direction of the yarn, an opening portion having a crimped state and a single fiber present in a disjointed state, and the fused bundle portion and the opened portion being mixed and integrated. Multifilament yarn in which a mixed portion is formed, and the occupation ratio of the sum of the fusion bunched portion and the mixed portion in the yarn longitudinal direction is 35% with respect to the entire yarn.
９０90% and the length of the mixed portion is 8 mm or less, and the occupancy of the mixed portion in the yarn longitudinal direction is 3% 和 20% with respect to the sum of the fused bundle portion and the mixed portion. A partially fused false twisted yarn characterized by the fact that 2. The birefringence Δn is 20 × 10 ⁻³ to 70 × 1.
0 polyester highly oriented undrawn yarn of ^-3, draw ratio DR1 satisfying the following formula (a), (b), the temperature 60
Out-draw stretching at 135 ° C., followed by stretching ratio D
R2, when performing false-twisting at a false-twisting temperature of 200 to 240 ° C., the interdrawing of the feed roller is intermittently performed, so that the outdraw stretching is performed intermittently. Manufacturing method of yarn. NDR × 0.6 ≦ DR1 ≦ NDR × 0.9 (B) NDR × 0.7 ≦ DR1 × DR2 ≦ NDR × 1.0 (B) (However, NDR represents a natural stretching ratio) ) 3. The method according to claim 1, wherein a surface temperature of 60 to 60 is applied during outdraw stretching.
The method for producing partially fused false twisted yarn according to claim 3, wherein a pin heater at 120 ° C is used.