JP3373402B2 - Special composite false twisting yarn and method for producing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a special composite false twist textured yarn having a rayon-like texture with a smooth surface touch and a method for producing the same. More specifically, the hollow filament pulsing in the hollow state along the longitudinal direction of the filament, and the hollow filament whose cross-sectional shape is flat, is a special composite false twisted yarn of a two-layer structure in which the hollow filament is wound around the core yarn as a sheath and the same. The present invention relates to a manufacturing method.

[0002]

2. Description of the Related Art Heretofore, there has been known a method for obtaining a two-layer structured yarn which is bulky and has an excellent warmth feeling by aligning and intertwining two or more kinds of filament yarns having different elongations and subsequently false twisting them. (For example, Japanese Patent Publication No. 60-11130)
Gazette, Japanese Examined Patent Publication No. 61-19733, etc.). However, although these two-layer structured yarns are excellent in bulkiness, they exhibit strong crimping due to false twist, have a strong sense of coarseness due to cross-sectional deformation, and exhibit a unique slimy feel, so that midsummer There has been a problem that it cannot be fully used for applications requiring a sharpness and a refreshing feeling such as outerwear.

In order to solve such a problem, JP-A-7-
Japanese Patent No. 118976 discloses a method for producing a two-layer structured yarn in which two types of polyester multifilament yarns having different elongations are entangled and then low temperature draw false twisting is performed at a low draw ratio. However, in the two-layer structured yarn obtained by such a method, the filament forming the sheath portion undergoes neck stretching and becomes a thick and thin (thick and thin) form, so that the slimy feel of the polyester can be wiped off, but The rough feeling of surface touch is still strong, and the drapeability is insufficient.

Japanese Patent Laid-Open No. 9-132835 discloses that
Two layers in which the difference in elongation is 300% or more and the filaments on the high elongation side are entangled with two types of filaments having a hollow portion with a hollow ratio of 20% or more, and then low-temperature draw false twisting is performed at a low draw ratio. A method for producing a composite false twisted textured yarn is disclosed.
However, although a double-layered structure yarn having a soft feeling and an excellent lightweight feeling can be obtained by such a method, since the elongation of the filament on the high elongation side is large, neck stretching occurs during the stretch false twisting process and the sheath portion The filament tends to be thick and thin (thick and thin), and due to the uneven distribution of air in the hollow portion during false twisting, the hollow portion is partially enlarged too much and the hollow membrane becomes thin, resulting in weaving. There is a problem in that hollow breakage is likely to occur in the process, dyeing process, or alkali reduction process, and a rayon-like texture cannot be obtained with a smooth surface touch.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems of the prior art and to provide a special composite false twisted yarn having a smooth surface touch and a rayon-like texture, and a method for producing the same. To do.

[0006]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have made the elongation difference between two kinds of filaments having an elongation difference 200% or less, and
When a hollow filament is used as the filament on the high elongation side and drawn and false twisted under specific conditions, the hollow state and the thickness (fineness) cause pulsing along the longitudinal direction of the hollow filament, and the hollow portion is broken. It was clarified that a composite false twist textured yarn having a difficult and desired texture was obtained.

Thus, according to the present invention, (1) highly oriented polyester multifilament (A)
In a two-layer structure false twisted textured yarn in which the low orientation polyester multifilament (B) is wound around the core as a sheath, and the sheath filament is pulsing in the hollow state along the longitudinal direction, A hollow filament having a maximum hollow ratio of 1.4 times or less the hollow ratio before false twisting, and the cross-sectional shape of the sheath filament in the cross section of the composite false twisted yarn has a flatness of 1.5. ~ 4.5
And, the special composite false twisted yarn, wherein the hollow ratio is distributed in the range of 0 to 60% , and the crushed ratio of the hollow part is 50% or less, and (2) Birefringence Unstretched highly oriented polyester multifilament (A ′) having a rate of 0.07 to 0.11, and unstretched having a breaking elongation of 50 to 200% larger than that of (A ′) and a hollow ratio of 20% or more. A low-orientation hollow polyester multifilament (B ') is mixed and the following (a) to
It is characterized by performing simultaneous drawing false twisting under the false twisting condition (d), and then performing heat treatment at a temperature of 150 ° C. or higher.
The method for producing a special composite false twisted yarn according to 1 above . (A) 0.4 ≦ DB / (DA + DB) ≦ 0.7 where DA is the total fineness of the unstretched highly oriented polyester multifilament (A ′), and DB is the unstretched low oriented hollow polyester multifilament (B ′). Represents the total fineness. (B) Stretching ratio (DR): 1.1 ≦ DR ≦ 1.4 (c) False twist number (T): 13000 / (DA + DB) ^1/2
≦ T ≦ 30000 / (DA + DB) ^1/2 (d) The yarn temperature (T
E): 70 ° C. ≦ TE ≦ 100 ° C. are provided.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described with reference to the accompanying drawings.
The details will be described. FIG. 1 is an example of a cross-sectional view of a composite false twisted textured yarn of the present invention, and FIG. 2 is an example of a cross-sectional view of a conventional composite false twisted textured yarn. FIG. 3 is a side view showing an example of a manufacturing apparatus for manufacturing the composite false twisted textured yarn of the present invention.

In FIG. 3, unstretched highly oriented polyester multifilament (A ') of creel 1 and unstretched low oriented hollow polyester multifilament (50' to 200% higher than that of creel 2 (A ')). B ') is aligned and supplied from a pair of supply rollers (5),
After being entangled with each other by the air entanglement nozzle (6), they are sent to the first heater (8) and the false twisting tool (9) through the intermediate roller (7), and twisted, heat set and untwisted.

Further, the false twisted composite false twisted yarn is subsequently heat treated by a second heater (11) through a delivery roller (10) and a take-up roller (1).
2) The cheese is wound on the winder (13) as cheese (14).

At this time, the unstretched highly oriented polyester multifilament (A ') has a birefringence of 0.07-.
It is important to use 0.11 and to set the difference in elongation between the (A ') and the unstretched low orientation hollow polyester multifilament (B') to 50 to 200%. Elongation difference is 5
If it is less than 0%, a composite false twisted yarn having a two-layer structure cannot be obtained and pulsing in a hollow state becomes insufficient. On the other hand, when it exceeds 200%, the pulsing of the sheath filament in the hollow state becomes too large, and the cross-sectional shape of the sheath filament also deforms too much, so that stain spots and streaks are likely to occur, which is advantageous. The resulting fabric also has a sharp feeling and cannot achieve the object of the present invention.

The unstretched highly oriented polyester multifilament (A ') [hereinafter sometimes simply referred to as A'] is preferably a solid polyester multifilament having an elongation of 50 to 130%. 4000m
Examples thereof include a method obtained by spinning at a high speed of not less than 1 minute / minute, and a method obtained by subjecting this to heat treatment.
Among them, those spun at a speed of 5000 m / min or more are preferable. On the other hand, the unstretched low-orientation hollow polyester multifilament (B ') on the high elongation side [hereinafter sometimes simply referred to as B'] has an elongation of 100 to 200%.
It is preferable that the spinning speed is in the range of 2,500 to 5,000.
Those obtained at 3500 m / min are preferred.

Next, it is necessary that the hollow ratio of the hollow filament (B ') is 20% or more, and the hollow ratio is 2%.
When it is less than 0%, pulsing in a hollow state does not sufficiently occur along the longitudinal direction of the filament, which is not preferable. However, if the hollow ratio is too high, fibrils are likely to be generated, and the weaving property is deteriorated. The above unstretched low orientation hollow polyester multifilament (B ')
Can be produced by a conventionally known method.

The above A 'and B'are the total fineness DA.
And DB must satisfy the following formula. 0.4 ≦ DB / (DA + DB) ≦ 0.7 where DA is the total fineness of the unstretched highly oriented polyester multifilament (A ′) and DB is the total fineness of the unstretched low oriented hollow polyester multifilament (B ′). Represent

When the proportion of the hollow filament B'is less than 40%, A'dominates, and the effect of pulsing the hollow state of the sheath filament of the obtained composite false twisted yarn is lowered, It is not preferable because the smoothness of the surface touch is reduced. On the other hand, when it exceeds 70%, not only the proportion of the core portion of the obtained composite false twisted yarn is reduced and the repulsion property is lowered, but also the twisting load on B'during false twisting becomes too large, The flatness of the sheath filament and the crushing of the hollow portion are unbalanced and the object of the present invention cannot be achieved.

In the false twisting process, it is necessary to set the yarn temperature at the exit of the false twist heat fixing heater to 70 to 100 ° C. When the yarn temperature at the outlet is less than 70 ° C., the twisting tension becomes too high, which causes dyeing unevenness and unevenness. On the other hand, when the yarn temperature exceeds 100 ° C., the crimping rate becomes too high, and the obtained woven fabric has a fluffy texture.

The yarn temperature at the exit of the false twist heat fixing heater is set to 70.
To set the temperature to 100 ° C, the drawing false twist heater temperature is set to 80
The heating may be performed at 120 ° C. for 0.2 to 0.4 seconds.

The draw ratio for false twisting is 1.
It must be in the range of 1 to 1.4. If the draw ratio exceeds 1.4, fluff occurs frequently, the processability in the post-processing steps such as weaving and dyeing is deteriorated, and the quality of the obtained woven fabric is also deteriorated, which is not preferable. On the other hand, when it is less than 1.1, the composite processed yarn obtained is likely to cause uneven dyeing due to the yarn shake during false twisting, which is not preferable.

The number of false twists (T) in the false twisting process
Must be set to satisfy the following formula. 13000 / (DA + DB) ^1/2 ≦ T ≦ 30000 /
When the (DA + DB) ^1/2 false twist number is within this range, it is possible to suppress vibration of the twisted yarn and variation in the twist number due to ballooning, and to reduce the hollow collapse ratio in the longitudinal direction of the yarn. It is possible to stably pulsing the hollow state while maintaining the content at 50% or less, and thus it is possible to stably obtain a composite false twisted yarn having a rayon-like texture with a smooth surface touch.

Next, the heat treatment with the second heater (11) may be carried out under the conditions that the shrinkage of boiling water of the obtained composite false twisted yarn is 3 to 7%. In the case of false twisting under the above conditions Requires a temperature of 150 ° C. or higher. However, if the temperature becomes too high, fusion between filaments may occur, so it is preferable to stop the temperature at 220 ° C. at most.

The polyester in the present invention contains terephthalic acid as a main acid component and at least one glycol, preferably at least one alkylene glycol selected from ethylene glycol, trimethylene glycol, tetramethylene glycol and the like. The polyester is used as a glycol component, and an isophthalic acid component containing a sulfonic acid metal salt, such as 5-sodium sulfoisophthalic acid or 5-tetrabutylphosphonium sulfoisophthalic acid, is used in the polyester by a known method. It may be polymerized, or may be one added with a stabilizer, an antioxidant, a flame retardant, an antistatic agent, a fluorescent color enhancer, a catalyst, a colorant, inorganic fine particles and the like within a range that does not impair the object of the present invention. .

The composite false twisted yarn produced by the method described in detail above has the highly oriented polyester multifilament (A) as the core portion (hereinafter sometimes referred to as the core yarn),
A low orientation hollow polyester multifilament (B) is wound around it as a sheath portion (hereinafter sometimes referred to as sheath yarn) to form a two-layer structure, and the hollow state of each hollow filament constituting the sheath yarn is Since pulsing is performed while making the phases different from each other, as shown in FIG. 1, hollow filaments from a completely crushed state to a state in which the hollow ratio is expanded as compared with that before false twisting are mixed in any cross section thereof. You get what you did.

That is, in the above false twisting process, the low orientation hollow filament (B ') is easy to extend, while the high orientation filament (A') is difficult to elongate, so the outer circumference of the high orientation filament (A ') is low. The low orientation hollow filament (B ') is wound around the portion, and the hollow filament (B') is stretched by the length required for winding.

Since the hollow filament (B ') is stretched while being twisted, the air present in the hollow portion is pushed out in the longitudinal direction of the filament, and the hollow portion has a hollow ratio different from each other in phase. It becomes a pulsing state in which the fluctuations are repeated while doing so.

At this time, it is important that the maximum hollow ratio of the hollow filament is 1.4 times or less, preferably 1.1 to 1.3 times the hollow ratio before false twisting. When the maximum hollow ratio exceeds 1.4 times, the feeling of lightness of the obtained textured yarn increases, but since the hollow part is partially enlarged greatly, pulsing spots are likely to occur, and uneven thickness and
Fibrillation is likely to occur in a portion having a large hollow ratio. For this reason, the weaving property is lowered, it is easy to cause dyeing spots at the time of dyeing, and further, when the alkali weight loss treatment is performed, hollow breakage occurs and the smoothness of the surface touch cannot be obtained. Can not do.
On the other hand, the lower limit of the expansion ratio of the maximum hollow ratio to the hollow ratio before false twisting is not particularly limited, but if it is too small, pulsing in the hollow state will be insufficient and smooth surface touch will occur. In some cases, a composite false twisted textured yarn having a rayon-like texture may not be obtained.

Furthermore, in the composite false twisted yarn of the present invention, the flatness of the hollow filament (sheath yarn) in the outer peripheral cross-sectional shape is 1.5.
~ 4.5, preferably 1.8-4.0, within the cross section
The hollow ratio of each filament in the filament is 0-60%, which is preferable.
In other words, it is necessary that the content is distributed in the range of 0 to 40% and that the hollow portion is crushed at a rate (hollow rate 0%) of 50% or less, preferably 30 to 50%. When the flatness is less than 1.5, artificial glare (irritability) occurs, so that the rayon-like texture intended by the present invention cannot be obtained, while when it exceeds 4.5. Is unfavorable, because an acute-angled portion is present in the cross-sectional shape to give a rough feeling.

When the distribution of the hollow ratio in the cross section is out of the above range, not only the proportion of the pulsing in the hollow state becomes too large, but also the deformation of the cross-sectional shape of the sheath yarn becomes too large, which is also smooth. It is not preferable because it is not possible to obtain a rayon-like texture with a smooth surface touch.
Furthermore, when the ratio of the sheath yarn in the state where the hollow portion is crushed exceeds 50%, the pulsing balance in the hollow state is lost,
The random arrangement of single yarns having different hollow states and the mixing effect are deteriorated and the surface touch is deteriorated, so that the object of the present invention cannot be achieved.

The flatness referred to here is defined by the following equation, where LA is the longest axis diameter in the cross section of the hollow filament and LB is the maximum width in the direction orthogonal thereto. Flatness = LA / LB In addition, the fact that the hollow ratio is distributed in the range of 0 to 60% means that
Sheath yarn (hollow filament) in any cross section of false false twisted yarn
Of the filament hollowness of each
The hollow ratio of the hollow part is in the range of 0 to 60% (hollow part
The crushed one is expressed as 0% hollow ratio) .

Further, the crushed ratio of the hollow portion is such that each sheath yarn of the composite false twisted yarn of the present invention is pulsing in a hollow state having phases different from each other, and its arbitrary cross section is shown in FIG. Since at least three types of filaments having the following cross sections are mixed, they are defined by the following formula. The cross-sectional shape before false twisting and the cross-section where the hollow ratio is substantially maintained, the cross-sectional shape before false-twisting is maintained, while the hollow ratio is increased, the flattened by the false-twisting process, and the hollow The cross-section of which the ratio is smaller than that before false twisting, the cross-section that is flattened by false-twisting, and the hollow ratio is completely collapsed, The ratio of hollow part collapsed (%) = (/ (+++
)) X 100

[0030]

In the double-layered composite false twisted yarn of the present invention, the hollow filament of the sheath yarn is pulsing in the hollow state along the longitudinal direction, and the pulsing state is different from the conventional one. The crushed ratio of the part is 50% or less, and the maximum hollow ratio is suppressed to 1.4 times or less of the hollow ratio before false twisting, so it is hollow in the weaving process, dyeing process, alkali reduction processing process, etc. Breakage is unlikely to occur, and the flatness and hollowness of the cross section are controlled within a specific range,
It is possible to obtain a cloth having a rayon-like texture with a smooth surface touch without feeling of coarseness and hardness.

Further, according to the production method of the present invention, the multifilament (B ') which is the sheath yarn of the two-layer structure yarn has a difference in elongation of 50 to 2 from the multifilament (A') which is the core yarn.
Since it has a hollow portion with a hollowness of 20% or more, it has a hollow ratio of 20% or more.
The sheath yarn is deformed into a flat cross-sectional shape in a state of holding a hollow part and pulsing in the longitudinal direction, and in a state in which the hollow flat cross section is randomly twisted in the longitudinal direction,
The individual yarns are arranged in different phases. Moreover, since the filament (B ') that becomes the sheath yarn has a small difference in elongation from A', the resistance to the twisting load in false twisting becomes large, and the hollow state The pulsing volatility of has decreased. Combined with these effects, it is possible to obtain a composite false twisted yarn having a smooth surface touch, no dyeing spots (irrancy), and an excellent refreshing feeling.

[0032]

EXAMPLES The present invention will be described in more detail below with reference to examples. In addition, each physical property in an Example was measured by the following method.

<Distribution of hollowness in cross section> A cross-sectional micrograph (magnification: 500 times) of a composite false twisted yarn is arbitrarily set to 20.
An image was taken at each location, the hollow ratios of all the sheath filaments (hollow filaments) in each cross section were measured, and the measured values at 20 locations were displayed as a range. The maximum value among the hollow rates was defined as the maximum hollow rate.

<Flatness> In the above cross-sectional photograph, when the longest axis diameter in the cross section of the hollow filament is LA and the maximum width in the direction orthogonal thereto is the short axis diameter LB, it is defined by the following equation. Flatness = LA / LB

<Crimp ratio (TC)> A sample of about 3,000 denier is made by applying a tension of 50 mg / denier to the sample and winding the sample on a frame. After making the case, 2 mg at one end of the case
/ Denier + 200 mg / denier load, 1
The length L ₀ (cm) after a lapse of minutes is measured. Then 2
100 ℃ with the load of 00mg / denier removed
In boiling water for 20 minutes. After the treatment with boiling water, the load of 2 mg / denier is removed, and it is naturally dried for 24 hours in a free state. 2 mg / denier +2 again on the naturally dried sample
A load of 00 mg / denier is applied, and the length L ₁ (cm) after 1 minute is measured. Then, the load of 200 mg / denier was removed, the length L ₂ after 1 minute was measured, and the crimp ratio was calculated by the following formula. TC (%) = [(L ₁ −L ₂ ) / L ₀ ) × 100 The measurement was performed 10 times, and the average value was shown.

<Boiling Water Shrinkage> A skeleton of a composite false twisted yarn having a denier of about 3000 was made, a load of 0.1 g / denier was applied to the skeleton to measure the original length l ₀ (cm), and then the skeleton load. Was changed to 2 mg / denier, and this was heat-treated in boiling water for 30 minutes and dried at room temperature, then the load was changed to 0.1 g / denier and the length l ₁ (cm) was measured. The boiling water shrinkage ratio was calculated. Boiling water shrinkage BWS (%) = (l ₀ −l ₁ ) / l ₀ × 10
0 The measurement was performed 10 times and the average value was shown.

<Handling of Composite False Twisted Yarn> The obtained composite false twisted yarn is knitted by a cylinder knitting machine and scoured according to a conventional method.
The texture (softness) and surface touch of the knitted fabric after dyeing and final setting were sensory-evaluated by five experts.
The judgment was expressed in 5 stages from 1 (poor) to 5 (very good). It should be noted that 4 or higher was regarded as a passing level.

[Example 1] A polyethylene terephthalate polymer was melted and discharged from a spinneret for hollow fiber spinning, and then spun at a spinning speed of 3000 m / min to give a hollowness of 29%, an elongation of 130%, and a density of 150 denier / 48 filaments. Hollow polyester filament yarn (B ') was obtained. Next, a polyethylene terephthalate polymer was melt-discharged by a conventional method and then spun at a spinning speed of 4600 m / min to obtain a birefringence of 0.085, an elongation of 70%, and a highly oriented unstretched (low) of 75 denier / 12 filaments. Elongation) A solid polyester filament yarn (A ') was obtained.

Next, both filament yarns were supplied to the false twisting apparatus shown in FIG. 3 and subjected to the entanglement treatment under the conditions of an overfeed rate of 2% and a pneumatic pressure of 2.5 kg / cm ² . Subsequently, both filaments were heat-set for 0.3 seconds with the first heater set to 95 ° C., the yarn temperature at the heater outlet was set to 85 ° C., and the triaxial friction false twisting was performed at a surface speed of 630 m / min. The film was guided to a device and drawn and false twisted under the conditions of a draw ratio of 1.25 and a processing speed of 400 m / min. The false twist number T (turns / m) at this time was 1500.

Further, the above composite false twisted yarn was introduced into a second heater at 200 ° C. with an overfeed rate of 0% and subjected to heat treatment, and then wound on a winder, 185 denier / 60 filaments, elongation 40%, A composite false twisted yarn having a crimp rate of 1.3% and a boiling water shrinkage rate of 4.5% was obtained.

The obtained composite false twisted yarn has a two-layer structure in which a hollow sheath yarn is wound around a solid core yarn,
Further, when the cross-sectional shape of the hollow filament in an arbitrary cross section was observed, as shown in FIG. 1, the flatness averaged 2.
5 and the crushing rate of the hollow part is 33%, hollow filament yarns having the following cross sections are mixed, and in the hollow state, there is a phase difference between the filaments along the longitudinal direction of the yarn. Was pulsing. The distribution of the hollow ratio in the cross section of the hollow filament was in the range of 0 to 38%.

The cross-sectional shape before the false twisting and the cross section in which the hollow ratio is substantially maintained, the cross-sectional shape before the false twisting is maintained, while the hollow ratio is increased in the cross section, which is flattened by the false twisting process. , And the cross-section where the hollow ratio is smaller than that before the false-twisting process, the cross-section that is flattened by the false-twisting process and the hollow ratio is completely collapsed,

The knitted fabric obtained by knitting the obtained composite false-twisted yarn with a tubular knitting machine and dyeing and finishing it according to a conventional method had an excellent drape feeling and a smooth texture.
In addition, a twisted yarn of 1800 T / m was applied to the composite false twisted yarn, and the warp density was 176 yarns / 3.79 cm and the weft density was 106 yarns /
Weave in a twill structure at 3.79 cm, and relax (temperature 120 ° C, 20 minutes), preset (temperature 180 ° C, 45 seconds), alkali weight loss treatment (weight loss rate: 1) according to a conventional method.
7%), a dyeing process (temperature 130 ° C., 45 minutes), and a final set (temperature 160 ° C., 45 seconds) to obtain a woven fabric. The obtained woven fabric exhibited a smooth surface touch and an excellent drape property, and was excellent in a refreshing feeling.

[Comparative Example 1] A polyethylene terephthalate polymer was spun at a spinning speed of 1300 m / min, the elongation was 360%, the birefringence was 0.015 and 150 denier / 48.
A solid polyester filament yarn of filament was obtained. Next, a polyethylene terephthalate polymer was spun according to a conventional method at a spinning speed of 4600 m / min to give a birefringence of 0.085, an elongation of 70%, and a denier of 75/12.
A highly oriented undrawn solid polyester filament of the filament was obtained.

Both filaments were false twisted in the same manner as in Example 1. When the obtained false-twisted composite yarn was visually observed with a two-layer structure yarn using a stereoscopic microscope, it was found that the sick and thin portions were mixed in the sheath yarn.

When this processed yarn was subjected to fabric processing in the same manner as in Example 1, the obtained fabric was excellent in crispness, but had a rough surface touch and poor drape property. there were.

[Examples 2 to 7, Comparative Examples 2 to 7] Example 1
In Example 1, the same procedure as in Example 1 was carried out except that the raw yarn characteristics and the false twisting conditions were changed as shown in Tables 1 and 2.
Physical properties of the obtained composite false twisted yarn and knitted fabric are shown in Tables 1 and 2.

[0048]

[Table 1]

[0049]

[Table 2]

[0050]

According to the manufacturing method of the present invention described above, the sheath yarn of the composite false twisted textured yarn having the two-layer structure has a pulsing in a hollow state (the hollow ratio is dispersed in a specific range and the cross-sectional shape is various). Mixed with each other), and further, a ribbon-shaped natural twist is partially formed due to the flattened cross section. Combined with these structures, the composite false twisted yarn of the present invention has a smooth surface touch, has a smooth surface, has a high drape property, has a rayon-like texture, and is excellent in coolness. To be Therefore, it can be suitably used for textile applications for midsummer, and its industrial value is extremely great.

[Brief description of drawings]

FIG. 1 is an example of a cross-sectional view of a special composite false twisted yarn of the present invention.

FIG. 2 is an example of a cross-sectional view of a conventional composite false twisted yarn.

FIG. 3 is a side view showing an example of a production apparatus for producing the composite false twisted yarn of the present invention.

[Explanation of symbols]

1 Highly oriented filament (A ') [creel 1] 2 Low orientation hollow filament (B ') [Creel 2] 3 guides 4 Tension adjusting device 5 supply roller 6 air confounding nozzle 7 Intermediate roller 8 first heater 9 False twisting tool 10 Delivery roller 11 Second heater 12 Take-up roller 13 winder 14 cheese

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) D02G 1/00-3/48 D02J 1/00-13/00

Claims (2)

(57) [Claims] 1. A composite false twisted yarn having a two-layer structure in which a highly oriented polyester multifilament (A) is used as a core portion, and a low orientation polyester multifilament (B) is wound around the core portion as a sheath portion. Is composed of hollow filaments whose hollow state is pulsing along the longitudinal direction and whose maximum hollow ratio is 1.4 times or less of the hollow ratio before false twisting, and the sheath in the cross section of the composite false twisted yarn. The cross-sectional shape of the partial filament has a flatness of 1.5 to
At 4.5, the hollow ratio is distributed in the range of 0 to 60%.
And the crushed ratio of the hollow part is 50% or less, a special composite false twisted yarn. 2. An unstretched highly oriented polyester multifilament (A ′) having a birefringence of 0.07 to 0.11, and a breaking elongation of 50 to 200% larger than that of (A ′) and a hollow ratio. 20% or more of unstretched low-orientation hollow polyester multifilament (B ') is mixed and the following (a)-
It is characterized by performing simultaneous drawing and false twisting under the false twisting condition of (d), and then performing heat treatment at a temperature of 150 ° C. or higher.
The method for producing a special composite false twist textured yarn according to claim 1 . (A) 0.4 ≦ DB / (DA + DB) ≦ 0.7 where DA is the total fineness of the unstretched highly oriented polyester multifilament (A ′), and DB is the unstretched low oriented hollow polyester multifilament (B ′). Represents the total fineness. (B) Stretching ratio (DR): 1.1 ≦ DR ≦ 1.4 (c) False twist number (T): 13000 / (DA + DB) ^1/2
≦ T ≦ 30000 / (DA + DB) ^1/2 (d) The yarn temperature (T
E): 70 ° C. ≦ TE ≦ 100 ° C.