JP3538065B2 - Method for producing composite false twisted 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 composite false-twisted yarn which is excellent in bulkiness and softness, has no spots, and has a new feel with a smooth surface touch. More specifically, the present invention relates to a method capable of producing a composite false twisted yarn having a two-layer structure in which a sheath yarn is wound around a core yarn along the longitudinal direction of a filament with high production efficiency and high speed.

[0002]

2. Description of the Related Art Conventionally, two or more filament yarns having a difference in elongation are aligned and entangled, and subsequently subjected to false twisting, so that a composite false twisted yarn having a bulky and excellent warm feeling is obtained. There is a known method for obtaining
No. 0-11130, Japanese Patent Publication No. 61-19733, etc.). However, although these two-layer yarns are excellent in span feeling and bulkiness, they exhibit strong crimping due to false twist, strong rough stiffness due to cross-sectional deformation, and exhibit a unique slimy feeling. For this reason, there is a problem that it cannot sufficiently cope with applications requiring a rayon-like feeling such as outerwear for midsummer and a refreshing feeling with a slat. Furthermore, in the above-mentioned conventional method, since the false twist processing is usually performed after the yarns having different deniers are separately spun and aligned and entangled, in addition to low productivity, uneven spots are likely to occur due to non-uniform fiber mixing. In addition, there was a drawback that the feeling was not sufficiently satisfactory.

On the other hand, in recent years, application of a technique of mixing and entangled two or more filament yarns in a spinning process has been attempted. For example, a method of using a cooling difference by varying the die surface depth (Japanese Patent Application Laid-Open No. 60-252711), a method of using a spinneret having a discharge hole whose cross-sectional area continuously increases, and applying a high draft (particularly). Japanese Unexamined Patent Publication (Kokai) No. 4-194007) and a method utilizing the above-described combination of cooling difference and high draft (Japanese Unexamined Patent Publication (Kokai) No. 4-194010) have been proposed. However, even if these false-twisted yarns are subjected to normal false twisting, there is a problem that the bulky feeling is insufficient, the processed fluff is liable to occur, and the softness of the woven fabric is still insufficient. there were.

[0004] In addition to utilizing the draft difference, a mixed fiber spun yarn is obtained by suctioning a fluid only on the low draft side, and this is simultaneously drawn and false-twisted to form a two-layer structure yarn (Japanese Patent Laid-Open No. Hei 8- No. 120519) has been proposed.
However, in this method, the filament yarn spun at a low draft is partially entangled because it is sucked by the fluid, and as a result, the mixing property with the other filament yarn is reduced,
Scatter mottling due to non-uniform fiber mixing was liable to occur, and the bulkiness was insufficient and unsatisfactory. Furthermore, since there is a large variation between weights when the weight is increased, problems such as variation in dyeing properties and bulkiness are likely to occur, and when fabric is used, spots are likely to occur, and the texture is insufficient. Was.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art.
A new composite false twisted yarn that is excellent in bulkiness and softness, has no unevenness, and has a smooth surface touch feeling. It is to provide a manufacturing method.

[0006]

According to the research of the present inventors, the object of the present invention is to spin from a single spinneret or different spinnerets with a spinning draft difference of 10,000 to 100,000 ,
Two types of undrawn polyester multifilament yarns drawn at a speed of 1000 to 1500 m / min are mixed and obtained, and the following (1) and (2) are simultaneously satisfied and entangled:
Using a false twisting machine in which the false twist heat set heater is a non-contact type, the spinning mixed yarn having a number of 10 to 70 yarns / m is stretched under conditions that simultaneously satisfy the following (3) and (4). It has been found that this can be achieved by a method for producing a composite false twisted yarn characterized by simultaneous false twisting. (1) Birefringence (A) of undrawn polyester multifilament yarn spun at high draft: 0.02 ≦ A ≦
0.05 (2) Elongation difference (ΔL) between two types of undrawn polyester multifilament yarn: 70% ≦ ΔL ≦ 200% (3) False twist heat setting temperature (H): 250 ° C. ≦ H (4) Temporary Twist heat setting time (T): 0.05 seconds ≦ T ≦ 0.
10 seconds

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The polyester used in the present invention is mainly a polyester whose repeating unit is composed of at least 95 mol% of ethylene terephthalate units. Other components may be copolymerized within the following ranges. The copolymerization component is not particularly limited, and a conventionally known component can be arbitrarily used. For example, as the acid component, phthalic acid, isophthalic acid,
Examples thereof include dibasic acids such as 5-sodium sulfoisophthalic acid, adipic acid, sebacic acid, suberic acid and the like. Further, as the glycol component, butylene glycol, neopentyl glycol, bisphenol A,
Examples thereof include diol compounds such as 2,2-bis (4- (β-hydroxyethoxy) phenyl) propane.

[0008] In the present invention, the following polyesters (1) and (2) spun using the same or different spinnerets with a spinning draft difference of 10,000 to 100,000 are simultaneously used in the present invention. It is necessary to obtain unstretched polyester multifilament yarn having two types of orientation difference that is satisfactory and to subject the spun mixed yarn obtained by blending treatment, preferably blending and entanglement treatment, to simultaneous drawing and false twisting. . (1) Birefringence (A) of undrawn polyester multifilament yarn spun at high draft: 0.02 ≦ A ≦
0.05, preferably 0.025 ≦ A ≦ 0.045 (2) Elongation difference (ΔL) between two types of undrawn polyester multifilament yarn: 70% ≦ ΔL ≦ 200%, preferably 90% ≦ ΔL ≦ 180%

Here, when the difference in spinning draft is less than 10,000, the difference in elongation (ΔL) between undrawn multifilament yarns
The false-twisted crimped yarn obtained by reducing the particle size tends to be loose, and the bulk is insufficient, and the texture of the target textured yarn cannot be obtained. On the other hand, if the difference in the spinning draft exceeds 100,000, not only the spinnability of the high spinning draft component deteriorates, but also the occurrence of yarn breakage and fluff during false twisting increases, which is not preferable.

It is important that the two types of undrawn polyester multifilament yarns having the above-mentioned draft difference in spinning be further adjusted and set so that the difference in elongation (ΔL) falls within the above range. This elongation difference is 70
If it is less than%, the bulkiness of the obtained processed yarn will be insufficient, while if it exceeds 200%, it is not preferable because it becomes easy to generate spots.

The birefringence (A) of the undrawn polyester multifilament spun at a high draft is within the above-mentioned range. It is important for prevention, and if the birefringence is less than 0.02, spots become large due to heat set spots due to the occurrence of surging. On the other hand, if it exceeds 0.05, the fiber cross-sectional shape becomes non-uniform, thread breakage, fluff, etc. increase, which is not preferable.

Incidentally, the total denier ratio of these undrawn polyester multifilament yarns is 5: 5 to 3: 7.
(Core: sheath) It is preferable that there are many portions that become the sheath, and the total denier is 70 to 70 denier after false twisting.
A range of 300 denier is preferred. After the false twisting, each single yarn denier has a high draft side of 3 cores.
0-120 denier, low draft side which becomes a sheath thread is 40-
It is preferable to make it 180 denier.

The undrawn yarn having such a draft difference melts and discharges polyester from two different kinds of discharge hole groups in which the hole diameter difference is set to an appropriate value, and 1000 to 1500
Obtained by withdrawing at a speed of m / min.

[0014] The above-described undrawing of the undrawn yarn may be performed at a stage before the take-up roller or at a stage after passing through the take-up roller. The fiber mixing method is not particularly limited, and a conventionally known method may be appropriately selected. For example, a method in which the fibers are mixed and entangled by air pressure treatment using an interlace nozzle is preferable. If the number of confounds at this time is too large, the fluff tends to increase, while if too small, there is a tendency to cause unevenness due to poor fiber mixing.
Is appropriate.

In the present invention, when a mixed spun yarn satisfying the above-mentioned requirements is subjected to simultaneous drawing and false-twisting, the false-twist heat-setting heater is a non-contact type false-twisting machine. Set temperature (H) is 250 ° C. or higher, preferably 25 ° C.
Stretching simultaneous false twisting at 0 to 800 ° C, particularly preferably 300 to 700 ° C, and a heat treatment time (T) of 0.05 to 0.10 seconds, preferably 0.06 to 0.09 seconds. There is a need.

The false-twisting machine used in this case, in which the false-twist heat set heater is a non-contact type, may be any of conventionally known false twisting machines. For example, the type of simultaneous twisting type disclosed in Japanese Patent No. 2856260 may be used. A false twisting machine can be exemplified.

If the heat setting temperature of the false twist is less than 250 ° C., insufficient heat setting results in insufficient crimping, so that the processed yarn obtained is equivalent to a flat yarn and the bulkiness is reduced. It is not preferable because the feeling becomes worse. If the heat setting temperature of the false twist is too high, for example, if it exceeds 800 ° C., problems such as a decrease in the durability of the heater and an increase in energy cost occur, and also, in order to develop a good crimp. Since the heat setting time is significantly shortened, it is difficult to impart a stable crimp, and the quality of the processed yarn obtained tends to vary.

Next, the heat setting time (T) of the false twist is set to 0.1.
It is necessary to be in the range of 0.05 to 0.10 seconds, preferably 0.06 to 0.09 seconds, and if the heat setting time is less than 0.05 seconds, sufficient crimping cannot be provided, In addition, the strength of the obtained false twisted yarn also decreases, so that the desired soft feeling cannot be obtained, which is not preferable. Further, when the false-twisting speed is set to a high speed of 700 m / min or more, the problem that surging is likely to occur and the spots of staining become large tends to occur. On the other hand, when the heat setting time exceeds 0.10 seconds, not only the dyeability is reduced (lightly dyed) due to the heat set-over, but also staining spots are easily generated,
In addition, processing fluff is also likely to occur, and the quality of the processed yarn obtained is deteriorated, which is not preferable.

The false twisting tool of the simultaneous drawing and twisting machine used in the present invention has a friction disk having a hardness of 75 to 90 degrees, preferably 8 to 90 degrees.
A triaxial friction false twist type disk false twisting device comprised of a urethane disk having a thickness in the range of 0 to 85 degrees and a thickness of 7 to 12 mm, preferably 8 to 11 mm is preferable. The angle is preferably in the range of 35 to 45 degrees with respect to the rotation axis of the disk.

When the material of the friction disk of the triaxial friction false twist type disk false twisting device is urethane, the twistability of the unoriented polyester multifilament yarn on the low orientation side is particularly excellent, and the obtained processed yarn has high elongation. It is possible to suppress the decrease in the degree and the generation of fluff.

When the hardness of the friction disk is out of the above range and is about 95 degrees in the related art, the low orientation side undrawn polyester multifilament yarn spun at a low draft is drawn false twisted at a high speed. At this time, the amorphous filament yarn is twisted at a high speed and false-twisted while being stretched at a high magnification, so that the yarn is not only damaged and easily broken or fuzzed, but also a running yarn. The gripping force decreases,
Since slipping easily occurs between the running yarn and the friction disk, the twisting efficiency is reduced and it becomes difficult to provide sufficient crimp. On the other hand, the hardness of the friction disk was set
When the degree is less than the degree, the force for gripping the running yarn increases, but the friction disk becomes severely worn, shortening the service life, and thread breakage due to the friction disk wear is liable to occur. The hardness of the friction disk referred to herein is JIS K
It is measured by the method of 6301-1971.

Next, the thickness of the friction disk is related to the running angle of the yarn, but if the thickness is increased to 7 mm or more from the conventional value of about 5 mm, the twisting force is slightly increased. Although the yarn feed force increases, the yarn twisting force increases, so that stable processing can be performed even at a false twisting speed of 700 m / min or more. However, if the friction disk is too thick and exceeds 12 mm, the untwisting tension is too low, so that thread breakage or fluff is likely to occur, and the threading property becomes difficult. Although the number of friction disks is not particularly limited, a range of 4 to 9 disks is usually employed.

Next, when twisting is performed using the triaxial friction false twist type disk false twisting tool, the running angle of the yarn with respect to the disk rotation axis is suitably in the range of 35 to 45 degrees. In addition,
As shown in FIG. 4, the running angle here is
Means the angle θ formed between the disk rotation axis and the yarn running in contact with the outer circumference of the friction disk.

In the friction false twisting, a twisting force (indicated by cos θ in FIG. 4) for imparting a twist to the running yarn by rotation of the friction disk and a yarn feeding force for giving the running yarn a yarn feeding effect. (Indicated by sin θ in FIG. 4)
Occurs. The twisting force is important for imparting sufficient crimping performance to the running yarn, while the yarn feeding force is important for processing at high speed. Normally, the running state of the yarn tends to become unstable as the false twisting speed increases, and a method is adopted to stabilize the running state by increasing the twisting tension (tension on the entry side to the friction disk). However, since the untwisting tension (tension on the outlet side from the friction disk) increases along with this, thread breakage and fluff are likely to occur. This tendency is particularly noticeable as surging (yarn swaying) when draw false twisting a yarn having a low-oriented undrawn polyester multifilament yarn as in the present invention, and furthermore, there is also a problem of wear of the friction disk. Concerns are coming.

Therefore, in the present invention, as described above, the running angle θ of the yarn is 35 to 45 degrees, preferably 38 to 4 degrees.
By selecting within the range of 2 degrees, it is possible to enhance the yarn feeding action and reduce the untwisting tension without lowering the crimping performance of the processed yarn, and to reduce the untwisting tension to 700 m / min or more, particularly 800 to 800 m / min.
Processing at a high speed such as 1200 m / min becomes possible.
If the running angle θ is less than 35 degrees, the twisting force is increased, but the yarn feeding force is reduced, making it difficult to perform false twisting at high speed. On the other hand, when the running angle θ exceeds 45 degrees, the yarn feeding force increases, but the twisting force decreases, and the crimping performance and strong elongation characteristics of the processed yarn decrease. Occurrence is likely to increase.

In order to set the running angle within the range of 35 to 45 degrees, the diameter and thickness of the friction disks and the intervals between the friction disks may be adjusted as appropriate. The running angle θ is preferably set so as to be within the above range for all friction disks, and for this purpose, for example, it is preferable to use a guide disk. FIG. 3 shows an example of a preferably used triaxial friction false twist type disk false twisting tool, but the number and arrangement of the guide disks are not limited to those shown in the figure.

In the present invention, it is appropriate that the false twist twisting tension is in the range of 0.20 to 0.40 g / de. If the twisting tension is less than the above range, spotting due to surging is likely to occur, and if it exceeds the range, fluff and yarn breakage are likely to occur. In addition, if the untwisting tension is too low, spots of dyeing (spot untwisted shape) are likely to occur, while if it is too high, fluff is likely to occur frequently.
It is preferable to be in the range of 0.10 to 0.30 g / de.

Next, FIG. 1 is a schematic process drawing showing one embodiment of the manufacturing method of the present invention. In FIG.
The two types of undrawn polyester multifilament yarns having a draft difference, which have been subjected to the spinning and blending treatment in advance, are supplied to the draw simultaneous false twisting region by the feed roller 3 via the guide 2. Next, the sheet is twisted and untwisted by a friction disk while being stretched between the feed roller 3 and the first delivery roller 7, and is heated by a first false twist heat set heater (a non-contact type heat set heater) 4. Fixed. The false-twisted yarn is heat-set by a second heat set heater (reheat set heater) 8 between the first delivery roller 7 and the second delivery roller 9 as necessary, and then wound. It is wound up as a package 11 by a take-up roller 10.

[0029]

In the method for producing a composite false twisted yarn of the present invention described in detail above, a spun mixed yarn comprising two types of undrawn yarns having a difference in spinning draft is used. This gives a processed yarn having good uniformity and suppressed dyeing spots and spots. In addition, the stretch false twist processing conditions also use a non-contact type heater as a false twist heat set heater,
Since the heat setting temperature and the heat setting time are set to specific ranges, a novel composite false twisted yarn excellent in bulkiness and softness can be produced with high production efficiency and at high speed.

[0030]

The present invention will be described below in more detail with reference to examples. In the examples, the measurement of each characteristic value was in accordance with the following. <Spinning Draft> The ratio (S / T) between the take-up speed (S) and the linear discharge speed (T) of the polymer was calculated.

<Birefringence index> The birefringence was determined by measuring the retardation and yarn diameter of a single yarn by a compensator method using an Olympus BH-2 polarizing microscope. <Cutting elongation of undrawn polyester multifilament>
The measurement was performed according to JIS L-1013-75.

<Spinning process condition> When the yarn was wound up at a winding amount of 7 kg, it was judged as follows based on the percentage of the yarn that could not be completely wound due to the breakage. ：: spinning breakage rate of less than 5%, Δ: spinning breakage rate of 5% or more and less than 10%, ×: spinning breakage rate of 10% or more,

<Crimp ratio (TC)%>
Apply a tension of 0 mg / denier and wind it on a skewer frame to make a scab of about 3000 deniers. After the cassette is made, a load of 2 mg / denier + 200 mg / denier is applied to one end of the cassette, and the length L ₀ (cm) after 1 minute is measured.
Next, it is treated in boiling water at 100 ° C. for 20 minutes with the load of 200 mg / denier removed. After the boiling water treatment, the load of 2 mg / denier is removed, and the product is air-dried in a free state for 24 hours. Add 2 mg /
A load of denier + 200 mg / denier is applied, and the length L ₁ (cm) after 1 minute is measured. Then, 20
The load of 0 mg / denier was removed, the length L ₂ after 1 minute was measured, and the crimp rate was calculated by the following formula. This measurement was performed 10 times, and the result was represented by the average value. TC (%) = [(L ₁ −L ₂ ) / L ₀ ] × 100

<Hand of composite false twisted yarn> The obtained composite false twisted yarn is knitted by a tubular knitting machine, scoured in a conventional manner,
After the dyeing and final setting, the texture (soft feeling) and the surface touch of the knitted fabric were comprehensively evaluated by a sensory evaluation by five skilled persons, and expressed in three stages as follows. It was expressed in three levels of first (poor), second (good), and third (very good).

<Bulkiness> Composite false twisted yarn sample 180
cm was wound into a skein (perimeter of 90 cm) and subjected to dry heat treatment at 180 ° C. for 5 minutes under a load of 6.0 g. Then, the processed yarn was loosened to remove entanglement due to shrinkage between the yarns. A sample is inserted into the groove 12 of the measuring device shown in FIG. 2, a plate weight 13 is placed, the scale 14 is read, and the volume (Vcm ³ ) of the sample is measured. The groove 1 of the measuring device
2 has a length of 12 cm and a width of 0.9 cm. Then
Both ends of the sample were cut off according to the 12 side surfaces, the sample weight W (g) after the cut off was measured, and V / W (c
m ³ ) was regarded as bulky.

<Processed Fluff> Using a DT-104 type fluff counter device manufactured by Toray Industries, Inc., 500 pieces of composite false twisted processed yarn was prepared.
The number of fluffs generated was counted by continuously measuring at a speed of m / min for 20 minutes.

<Boiling water shrinkage (BWS)> A skein of a composite false twisted yarn having a denier of about 3000 denier was prepared, and 0.1 g /
The original length L ₀ (cm) was measured by applying a load of denier, then the load of the scalpel was changed to 2 mg / denier, this was heat-treated in boiling water for 30 minutes, and then dried at room temperature. The length L ₁ (cm) was measured while changing to 0.1 g / denier, the boiling water shrinkage was calculated by the following formula, and the average value was obtained by measuring 10 times. Boiling water shrinkage (BWS) = (L ₀ −L ₁ ) / L ₀ × 100

<Running Angle> A photograph is taken of the yarn running on the friction false twisting tool, the running angle θ of the yarn on each friction disk is actually measured on the photograph, and the average of the measured values is measured. The value was taken as the running angle.

<Friction disk life> The number of months in which the diameter of the lowermost friction disk (excluding the guide disk provided to stabilize the running angle) was reduced by 1.0% was shown.

Example 1 Two types of undrawn polyester multifilaments subjected to spinning and entanglement with a draft difference of 77,000 (high spinning draft component: 120 denier / 24 filaments, birefringence 0.028, low Spinning draft component: 180 denier / 4
The simultaneous elongation false twisting was performed with the apparatus shown in FIG. 1 for 8 filaments with a cutting elongation difference of 150% and the number of entanglements of 25 / m). At that time, the false twist stretch ratio was 1.80 times, the non-contact type false twist heat set heater temperature (H) was 430 ° C. , and the false twist heat treatment time (T) was 0.075 seconds (heater length 1 m).
The false twisting tool is a triaxial friction disk (the friction disk is made of urethane rubber having a hardness of 83 degrees, and the thickness is 10 m.
m) at a running angle of 40 degrees between the yarn and the friction disk at a speed of 800 m / min.
A two-filament composite false twisted yarn was obtained. The resulting composite false twisted yarn had an extremely high bulkiness of 35 cm ³ / g.

The obtained composite false twisted yarn is knitted into a tubular knit,
The knitted fabric dyed and finished according to a conventional method had a smooth, smooth surface touch and a soft feel. The false twisted yarn was twisted at 1800 T / m to form a twisted yarn, and the warp density was 176 yarns / 3.79 c.
m, weft density: 106 strands / 3.79 cm.
0 minutes), preset (temperature 180 ° C, 45 seconds), alkali weight loss treatment (weight loss rate 17%), dyeing processing (temperature 130
° C, 45 minutes) and final set (temperature 160
(C, 45 seconds). The obtained woven fabric was an excellent woven fabric exhibiting a smooth surface touch and excellent drapability. Table 1 shows the results.

[Comparative Example 1] Polyethylene terephthalate was spun at a spinning draft of 156 at a spinning speed of 1300 m / min and had an elongation of 360%, a birefringence of 0.015, and a low orientation undrawn polyester multifilament of 150 denier / 48 filament. Yarn was obtained. Separately, spinning draft 188, spinning speed 320
Spun at 0 m / min, elongation 125%, birefringence 0.04
A highly oriented undrawn polyester filament yarn of 5,125 denier / 24 filaments was obtained.

After both filament yarns were aligned and mixed and entangled (50 entangles / m), a false twisting heat set heater was used as a contact heater and a false twisting machine was used. Stretching simultaneous false twisting was performed under the conditions of a heat setting temperature of 180 ° C. and a heat setting time of 0.21 second. At this time, a normal triaxial friction disk was used as the false twisting tool, and processed at a speed of 340 m / min to obtain 170 denier /
A composite false twisted yarn of 72 filaments was obtained. The bulkiness of the obtained false twisted yarn was as low as 20 cm ³ / g.

When the composite false twisting yarn was processed into a woven fabric in the same manner as in Example 1, the obtained woven fabric had a rough surface touch, and had a poor feel.
Table 1 shows the results.

Examples 2 to 4 and Comparative Examples 2 to 4 In Example 1, the difference in spinning draft was changed as shown in Table 1, and the birefringence of the undrawn yarn on the high draft spinning side and both undrawn yarns were changed. Example 1 was repeated except that the elongation difference of the yarn was changed as shown in Table 1. Table 1 shows the results.

[0046]

[Table 1]

Examples 5 to 11 and Comparative Examples 5 to 6 The same procedures as in Example 1 were carried out except that the conditions for simultaneous false-twisting in drawing were changed as shown in Table 2 or Table 3. The results are shown in Tables 2 and 3.

[0048]

[Table 2]

[0049]

[Table 3]

[0050]

According to the production method of the present invention, a composite temporary layer having a two-layer structure which is excellent in bulkiness and softness, hardly causes stain spots such as scum spots, and exhibits a smooth surface touch feeling. A twisted yarn can be easily obtained at high speed with high production efficiency.

[Brief description of the drawings]

FIG. 1 is a schematic view of an apparatus for producing a composite false twisting yarn used in Example 1.

FIG. 2 is a schematic diagram of a bulkiness measuring device.

FIG. 3 is a front view showing an example of a triaxial friction false twist type disk false twisting tool used in the present invention.

FIG. 4 is a schematic diagram for explaining a traveling angle of a yarn that travels in contact on the outer periphery of a friction disk.

[Explanation of symbols]

1 Polyester spun mixed yarn 2 Guide 3 feed roller 4 First heat set heater (false twist heat set heater) 5 Cooling plate 6 Twisting device (false twist disk) 7 First delivery roller 8 Second heat set heater (reheat set heater) 9 Second delivery roller 10 Winding roller 11 Package 12 grooves 13 Plate weight 14 scales 15,16,17 Rotation axis 18, 19, 20, 25 Guide Disk 21,22,23,24 Friction disk 26,27,28,29 Pulley 30 Drive belt

Continuation of the front page (56) References JP-A-4-194007 (JP, A) JP-A-9-279427 (JP, A) JP-A 8-120519 (JP, A) Patent 2856260 (JP, B2) ( 58) Field surveyed (Int.Cl. ⁷ , DB name) D02G 1/00-3/48 D02J 1/00-13/00

Claims (2)

(57) [Claims] 1. A spun at a spinning draft difference 10000-100000 from a single spinneret or different spinnerets, 1000
The following (1) and (2), which are obtained by blending two types of undrawn polyester multifilament yarns drawn at a speed of 1500 m / min, are simultaneously satisfied, and the number of entanglements is 10 to 10.
Using a false twisting machine in which a false twist heat set heater is a non-contact type, a 70-piece / m spun mixed yarn is simultaneously drawn and false-twisted under conditions that simultaneously satisfy the following (3) and (4): A method for producing a composite false twisted yarn. (1) Birefringence (A) of undrawn polyester multifilament yarn spun at high draft: 0.02 ≦ A ≦
0.05 (2) Elongation difference (ΔL) between two types of undrawn polyester multifilament yarn: 70% ≦ ΔL ≦ 200% (3) False twist heat setting temperature (H): 250 ° C. ≦ H (4) Temporary Twist heat setting time (T): 0.05 seconds ≦ T ≦ 0.
10 seconds 2. The false twisting tool of the false twisting machine has a hardness of 75 to 90.
Is a triaxial friction false twist type disk false twisting device composed of a urethane disk having a thickness of 7 to 12 mm, wherein the running angle of the yarn with respect to the rotation axis of the disk is 35 to 45 degrees, and the running speed of the yarn is The method for producing a composite false twisted yarn according to claim 1, wherein the yarn speed is 700 m / min or more.