JP3520937B2 - Method for producing polyester multifilament composite yarn - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a polyester multifilament composite yarn suitable for ladies' clothing, which satisfies both soft and dry touches, and has an appropriate bulge, beam and waist feeling . A manufacturing method is provided.

[0002]

2. Description of the Related Art Conventionally, as an attempt to satisfy a dry feeling and a soft feeling to a fabric, a polyester fusion multifilament is mainly used and a partial fusion type false twisted yarn or a special drawing method is used. The fineness of the yarn lengthwise,
Many approaches from thick and thin yarns with shrinkage spots have been proposed. However, although the partially fused false-twisted yarn has been considerably improved in terms of manufacturing cost, it has a sharp taste due to the effect of the fusion, so that it is treated by alkali reduction processing at the fused portion. There were drawbacks such as brittleness and poor drapability.

A thick and thin yarn having a cross-sectional area distribution in the fiber axis direction has an orientation degree distribution in the fiber axis direction. The thick portion has a low orientation degree and the thin portion has a high orientation degree. There is. It is understood that the thick portion having a low degree of orientation, that is, the unstretched state remaining portion simultaneously imparts an appropriate dry feeling that is characteristic of the thick and thin yarn and a bulge due to a high shrinkage ratio. This effect makes it possible to give a suitable dry feeling and bulge when using thick and thin yarn in the fabric, but the bulge of the thick and thin yarn is due to the contraction of the yarn, and the fabric has a suitable bulge. Although it has a feeling, it is finished to be tight, and the soft feeling and the drape property are not satisfied.

In addition, oriented crystallization is not sufficiently promoted in the thick portion, and when alkali weight reduction processing is performed, it is selectively hydrolyzed by alkali, and the degree of embrittlement is remarkable, the tear strength is lowered and the anti-pilling performance is reduced. There is a risk that the basic characteristics of the fabric may deteriorate, such as a decrease in For this reason, the range of suitability conditions in the post-processing steps such as dyeing processing is limited, and when the texture of the final product is taken into consideration, there is a problem that the variation cannot be easily expanded.

[0005]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned drawbacks of the prior art and provides a polyester multifilament composite comprising a polyester multifilament yarn having good physical properties of the obtained yarn and capable of stable production. it is an object of the present invention to provide a method for producing a yarn.
More specifically, it is a polyester that has moderate bulkiness, has elasticity, and has a soft texture and a dry texture when processed into a fabric, and is mainly suitable for ladies' clothing such as dresses, blouses, skirts, and slacks. there is provided a method for producing a multifilament composite yarn.

[0006]

The polyester multifilament composite yarn obtained by the present invention is suitable for woven and knitted fabrics, mainly for dresses, blouses, skirts, slacks and the like for women's clothing, and woven and knitted fabrics. When processed into, it is possible to give a proper bulge and firmness, and to give a softness and a proper soft feeling and dry feeling.

[0007]

The raw yarn for producing the polyester multifilament composite yarn of the present invention is a polyester multifilament containing an aromatic dicarboxylic acid as a main acid component and an aliphatic glycol as a main glycol component, particularly polyethylene terephthalate. The main target is a part of terephthalic acid, for example, isophthalic acid, 5-sodium sulfoisophthalic acid, dicarboxylic acid such as naphthalenedicarboxylic acid, or alicyclic dicarboxylic acid such as hexahydroterephthalic acid, or adipic acid, It is a polyester obtained by substituting an aliphatic dicarboxylic acid such as sebacic acid or a dihydric phenol such as bisphenol A, or a part of ethylene glycol with another glycol component such as trimethylene glycol or tetramethylene glycol. Is not particularly adding a restriction may be.

If desired, polyester containing inorganic fine particles such as titanium dioxide, silicon dioxide, zinc oxide, barium sulfate, zirconium oxide, aluminum oxide, magnesium oxide, calcium carbonate and kaolinite may be used. It may be appropriately selected according to In particular, it is considered that it is more preferable to use titanium dioxide or silicon dioxide having good dispersibility for polyester from the viewpoints of yarn quality, spinning, drawing, and post-processing operability.

The polymers used for the relaxation heat treated yarn (A) and the polyester multifilament drawn yarn (B) of the polyester multifilament undrawn yarn do not have to be the same, and may be used in an appropriate combination. In particular, when the polymer on the relaxation heat treated yarn (A) side of the polyester multifilament undrawn yarn is made of polyester containing inorganic fine particles, fine unevenness is formed on the fiber surface due to alkali weight reduction, and it is possible to impart a dry tactile sensation. Is preferred.

The composition denier of the polyester multifilament composite yarn obtained according to the present invention is not particularly limited, but its main product target is the use for women's clothing such as dresses, blouses, jackets, skirts and slacks. Then about 30 denier to 30
It should be appropriately selected within the range of 0 denier according to its purpose and application. The constituent single yarn denier is also not particularly limited, but in order to give an appropriate soft touch to the woven or knitted fabric, the relaxed heat treated yarn (A) of the polyester multifilament undrawn yarn is 0.1 denier or more and 3.5 or more.
The range is denier or less, more preferably 0.5 denier or more and 2.5 denier or less, and the monofilament denier of the polyester multifilament drawn yarn (B) is 1.0 denier or more and 20 denier or less, further preferably It is preferable to adopt a range of 3.0 denier or more and 15 denier or less. The single yarn denier of the drawn yarn (B) is 1.
When the range is less than 0 denier, it is suitable for woven and knitted fabrics,
The waist cannot be given, and the fabric becomes so-called loose. On the contrary, if the single yarn denier of the drawn yarn (B) exceeds 20 denier, sufficient drapeability cannot be imparted to the woven or knitted fabric unless the high weight loss condition is adopted during the alkali weight loss processing, and the high weight loss condition is satisfied. Due to the alkali weight loss, the relaxed heat treated yarn (A) side of the undrawn yarn is selectively subjected to a strong alkaline hydrolysis action, the degree of embrittlement is remarkable, and it becomes difficult to maintain the physical properties that can be practically used. It is not desirable.

The cross-sectional shapes of the relaxed heat-treated yarn (A) and the drawn yarn (B) of the undrawn yarn may not be the same, and are not particularly limited, and triangular cross-section yarns, other polygonal cross-section yarns, and flattened yarns It can be appropriately selected in consideration of the texture, the appearance quality, the surface effect, etc. of the woven or knitted fabric such as the cross-section yarn, the round-section yarn, and the other-shaped cross-section yarn. Regarding the cross-sectional shape, it is also possible to use a hollow cross section in addition to the solid cross section to express lightness and further improve the waist feeling. In addition, regarding this cross-sectional shape, it is not necessary that the constituent single yarns are all uniform,
It is also possible to use a modified cross-section fiber as a mixed fiber to improve the irregularity effect on the appearance and texture of the fabric.
A combination may be appropriately selected depending on the purpose.

The polyester multifilament composite yarn obtained by the present invention has , for example, a crystallinity (Xρ) of 20% or less and a dry heat shrinkage (SH) at a dry heat of 160 ° C.
D) is less than 0% and exhibits self-expansion, and the temperature (Tα) at which main dispersion by the dynamic viscoelastic method is 90 ° C. or higher and 125 ° C. or lower
Polyester multifilament undrawn yarn having a maximum mechanical loss tangent value [(Tanδ) max] of 0.20 or more and 0.30 or less has a relaxed heat treatment yarn (A) and a boiling water shrinkage ratio (SHW) of 5.0. % Or more and 60% or less and a dry heat shrinkage (SHD) at a dry heat of 160 ° C. of 7.0% or more and 80% or less and a polyester multifilament drawn yarn (B) are aligned or a high-pressure air stream at room temperature is used. The composite was made by the fiber mixing means by the air entanglement treatment used. Considering the handleability of the composite yarn, it is more preferable to combine the yarns by using a fiber mixing means.

The above-mentioned physical property values are based on the following measuring methods. (A) Crystallinity (Xρ) The specific gravity of the sample was measured in a thermostat at 20 ± 0.5 ° C by the density gradient tube method, and the crystallinity (Xρ) was calculated by the following formula. In the specific gravity measurement by the density gradient tube method, n-pentane (specific gravity 0.683) known as a light specific gravity liquid and carbon tetrachloride (specific gravity 1.599) as a heavy specific gravity liquid are adjusted and mixed, and the mixture is mixed. The solution was given a density gradient. The average value of 5 tests was used as the measured value. Xρ = [dk (d-da)] / [d (dk-da)] ×
100 (%) Xρ = crystallinity (%) dk = 1.47g / cm 3 (PET perfect crystal specific ^{gravity) da = 1.331g / cm 3 (} PET specific gravity of the complete amorphous) D = sample specific gravity (g / Cm ³ )

(B) Shrinkage rate of boiling water (SHW) A sample was measured at 0.1 g / d using a measuring machine with a frame circumference of 1.125 m.
The initial load is applied, and it is rewound at a speed of 120 times / minute to make a small ridge having 20 turns, and a weight 40 times the initial load is applied to measure the ridge length L0 (mm). Then remove the weight and use boiling water (100
C.) for 30 minutes, take out, wipe off water with absorbent paper or cotton cloth, and air dry in a horizontal state. After air-drying, the weight is applied again to measure the length L1 (mm). L above
Substituting 0 and L1 into the following equation, the boiling water shrinkage rate (SHW) is calculated. In addition, the average value of 5 times of the test is used as the measured value. SHW [(L0-L1) / L0] × 100 (%)

(C) Dry heat shrinkage (SHD) A load of 1/30 g / d is applied to the sample, and its length L0 (m
m) is measured. Then, the load is removed, and the sample is put in a dryer and dried at a dry heat of 160 ° C. for 30 minutes. After drying, it is cooled and a load of 1/30 g / d is applied again, and its length L1
(Mm) is measured. Substituting L0 and L1 into Equation 3,
The dry heat shrinkage (SHD) is calculated. In addition, the average value of 5 times of the test is used as the measured value. SHD = [(L0-L1) / L0] × 100 (%)

(D) Dynamic viscoelasticity measurement Using a Vibron DDV-IIC type manufactured by Orientec Co., a measurement frequency of 110 Hz, a heating rate of 1 ° C./min, a mechanical loss tangent Tan δ in a dry air atmosphere-temperature characteristic From the measurement result, the temperature (Tα) showing the main dispersion and the maximum value of the Tanδ curve [(Tanδ) max, which are closely related to the micro-Brownian motion shown by the segment of the polymer chain existing in the amorphous region, are shown. ]] Is read.

For example, crystallization of a relaxed heat-treated yarn (A) of a polyester multifilament undrawn yarn which constitutes a portion showing substantially self-elongation of the polyester multifilament composite yarn obtained by the present invention. Degree (Xρ) is 20
% Or less, and more preferably 15% or less. Excessively promoting crystallization is not preferable for imparting self-stretchability. At present, the details are not known, but it is estimated that the spinning take-up speed is 2000-4.
The polyester multifilament yarn melt-spun at 000 m / min. Is an undrawn yarn having a so-called highly oriented state, and its characteristic is that the degree of crystallization is relatively low. The rate of crystal growth in the crystal c-axis direction, that is, in the fiber axis direction by the wet heat treatment in the dyeing process, after the woven or knitted material is processed by removing the shrinkage component without increasing the crystallinity as much as possible, is applied. It is considered that the fiber becomes larger with respect to the heat shrinkage ratio of the yarn, and the fiber self-stretches substantially.

As described above, the spinning take-up speed of the polyester multifilament undrawn yarn subjected to the relaxation heat treatment is 2000 to 4000 m / min., More preferably 26.
00-3800 m / min., More preferably 3200-3
It is preferable to adopt a range of 600 m / min. If the spinning take-up speed is less than 2000 m / min., The orientation of the yarn is too low to impart self-stretching property, and the yarn does not exhibit self-stretching even when subjected to relaxation heat treatment, and the fiber is substantially Contracts, and the soft tactile sensation intended by the present invention cannot be satisfied.

The spinning take-up speed is 4000 m / min.
If it exceeds, the crystallinity becomes too high because so-called oriented crystallization is progressing, and conversely the heat shrinkability is extremely reduced. For this reason, sufficient relaxation heat treatment cannot be applied to the yarn, causing yarn sway due to insufficient heat shrinkage stress, and eventually causing yarn breakage due to winding around the supply roller portion, resulting in problems in terms of operability. In addition, the degree of incorporation of the polymer chain segment existing inside the amorphous region into the crystalline region due to excessively advanced crystal orientation, that is, the degree of crystal growth is small, and thus the yarn is substantially formed. Since the yarn does not exhibit self-stretching and the behavior of the yarn shifts to the contracting side, it is impossible to give the woven or knitted fabric an appropriate soft feeling due to self-stretching.

The relaxation heat-treated yarn (A) of the polyester multifilament undrawn yarn has a dry heat shrinkage (SHD) at 160 ° C. of less than 0% and exhibits substantially self-elongation.
The boiling water shrinkage (SHW) needs to be 3% or less. More preferably, it is 2% or less. The boiling water shrinkage is 3
If the content exceeds 100%, the yarn will shrink when the woven or knitted fabric is subjected to a relaxing treatment with boiling water, and the self-expansion that occurs in the subsequent steps such as tenter setting with a tenter or high temperature wet heat treatment with a dyeing machine is canceled by the shrinking action. There is a risk of
It is impossible to give a soft feeling to the woven or knitted fabric. The lower limit of the boiling water shrinkage ratio is preferably kept at -2% or more, more preferably -1% or more. When the boiling water shrinkage rate is less than -2%, the multifilament mixed filament yarn is twisted, and when a twist stop set is performed by a normal vacuum wet heat set,
Alternatively, during the warp sizing treatment, the relaxation heat treatment (A) shows self-expansion, which may hinder the operation of the subsequent warping and weaving / knitting processes, and the woven / knitted fabric self-expands after dyeing. Therefore, it becomes impossible to give a soft touch feeling sufficiently.

Further, the temperature (Tα) showing the main dispersion of the relaxed heat-treated polyester multifilament undrawn yarn (A) by the dynamic viscoelastic method is 90 ° C or higher and 125 ° C or lower, and the maximum value of the mechanical loss tangent [(Tanδ ) Max] is required to be 0.20 or more and 0.30 or less. As mentioned above, these values are the measurement frequency of 110 Hz and the heating rate of 1 ° C /
The mechanical loss tangent in a dry air atmosphere can be read from the measurement result of Tan δ-temperature characteristic, which is a physical property value closely related to the micro Brownian motion indicated by the polymer chain segment existing inside the amorphous region. .

If the temperature (Tα) indicating this main dispersion is in the range of less than 90 ° C., the yarn is in a thermally unstable state, and attention must be paid to giving a certain amount of heat. . In particular, when considering the twist setting and sizing conditions after twisting, it is necessary to perform the treatment at a temperature lower than the normal temperature, and if you try to perform the twist setting and sizing so as not to interfere with the subsequent process, the treatment time and It is essential to extend the drying time and the like, which causes an increase in running cost, which is not preferable. Further, in the range exceeding 125 ° C., that is, in the region where it is very stable thermally, it becomes difficult for the yarn to exhibit self-expansion, and it becomes difficult to impart the soft touch feeling to the woven or knitted fabric, which is the object of the present invention. Become. The temperature (T
α) is 90 ° C. or higher and 125 ° C. or lower, more preferably 105
By adjusting the spinning conditions and the relaxation heat treatment conditions so that the temperature is not lower than 120 ° C and not higher than 120 ° C, the yarn can be handled easily and can realize a soft feeling due to the effect of self-extension.

The maximum value of the mechanical loss tangent [(Tan
δ) max] needs to be 0.20 or more and 0.30 or less. This [(Tan δ) max] indicates the ease of micro Brownian motion of the polymer chain segment in the amorphous region. The smaller this value is, the more difficult the polymer chain segment is to move, and the yarn is It is known that the polymer chain segment is thermally stable, and the larger this value is, the easier it is for the polymer chain segment to carry out micro Brownian motion, and the yarn is structurally and thermally unstable.

Spinning take-off speed 2000-4000 m / min.
The polyester multifilament unstretched yarn obtained in 1. above has a slightly increased crystallinity due to relaxation heat treatment, and the [(Tanδ) max] value shows a slight decrease. However, if the crystallinity is excessively increased, [(Tanδ) max]
Decreasing the value means that the amount of the polymer chain segment in the amorphous region is substantially reduced, and the thermal mobility of the segment also decreases, so that the polymer chain segment in the amorphous region is a crystalline region. Crystal c
The degree of crystal growth in the axial direction becomes practically small, the self-stretching ability of the yarn is reduced, and it becomes impossible to impart a sufficient soft feeling to the woven or knitted fabric. The reason for this is not sufficiently clarified at present, and the detailed part cannot be understood, but this [(Tanδ) max] value is 0.2 or more.
The relaxation heat treated yarn (A) of the polyester multifilament unstretched yarn is substantially subjected to post-treatment such as dyeing by optimizing various conditions such as spinning conditions and relaxation heat treatment conditions so as to be in the range of 3 or less. Self-expanding.

The polyester multifilament drawn yarn (B) has a boiling water shrinkage (SHW) of 5.0% or more and 60% or more.
The range of 6.0% to 18% is more preferable, and the dry heat shrinkage (SHD) at 160 ° C of dry temperature is 7.0% to 80%, more preferably 9.0% or more. It is necessary to set the range to 20% or less. The drawn yarn (B) does not have to be a normally drawn yarn, and may be a thick and thin yarn having an orientation degree distribution in the yarn longitudinal direction. The boiling water shrinkage rate (SHW) is less than 6.0%, or the dry heat shrinkage rate (SHD) at a dry heat of 160 ° C is 7.0%.
Even if it is less than the range, the woven or knitted fabric may have a soft feeling and a swelling feeling due to the effect of the self-stretching of the relaxed heat treated yarn (A) of the polyester multifilament unstretched yarn, but it becomes slightly insufficient, The relaxation heat treated yarn (A)
It is desirable that the drawn yarn (B) to be combined with is to have appropriate shrinkage ability. However, the boiling water shrinkage (S
HW) exceeds 60% or dry heat shrinkage (SHD) at a dry heat of 160 ° C exceeds 80%. If the yarn has an extremely high shrinkage, the twisting setting conditions and sizing conditions are It is expected that the post-process passability will be impaired even after thorough examination, and it is in an unfavorable range considering the handleability of the polyester multifilament composite yarn.
Not suitable for use.

As the method for producing the polyester multifilament composite yarn of the present invention, the spinning take-up speed is from 2000 to
Atmospheric temperature of 160 ° C. to 2 without substantially stretching polyester multifilament unstretched yarn having boiling water shrinkage (SHW) of 50% or more spun at 4000 m / min.
Non-contact heat treatment is performed for 0.05 to 0.2 seconds under the condition of 30 ° C., the crystallinity (Xρ) is 20% or less, and the dry heat shrinkage rate (SHD) is less than 0% to cause substantially self-expansion. The temperature (Tα) showing the main dispersion by the dynamic viscoelastic method is 90 ° C. or higher and 125 ° C. or lower, and the maximum value of the mechanical loss tangent [(Tanδ)
[max] is 0.20 or more and 0.30 or less as a relaxed heat treated yarn (A) of a polyester multifilament undrawn yarn, and the polyester multifilament drawn yarn (B) is aligned or compounded by using a fiber mixing means. It is characterized by.

Spinning take-off speed is 2000-4000 m / mi
The non-contact heat treatment is performed at a temperature of 160 ° C. to 230 ° C. without substantially stretching the polyester multi-filament unstretched yarn having a boiling water shrinkage (SHW) of 50% spun at n. ~ 0.2 seconds to impart self-stretchability to the polyester multifilament unstretched yarn, but the excessive supply rate to the heating region in the heat treatment,
That is, the relaxation rate is 0% or more and 60% or less, more preferably 20%.
% Or more and 50% or less is effective in giving self-stretchability. When the relaxation rate exceeds 60%, the polyester multifilament undrawn yarn is insufficiently heat-contracted, so that the yarn is loosened, which causes flapping of the yarn and breakage of the yarn wound around the supply roller. Further, if the relaxation rate is less than 0%, the yarn is substantially stretched, which makes it impossible to impart self-stretchability to the yarn, which is not preferable. When the relaxation rate is 0% or more and 60% or less, more preferably 20% or more and 50% or less, it becomes possible to impart self-stretchability to the undrawn yarn, which is a preferable condition range.

The heat treatment has an ambient temperature of 160 ° C. to 23 ° C.
Non-contact type heat treatment under the condition of 0 ° C., more specifically, using a non-contact type slit heater, tube heater, etc., and the heater residence time is 0.05 to 0.2 seconds, more preferably 0.09 to It is characterized in that a relaxation heat treatment is applied for 0.18 seconds. The non-contact heater used for the heat treatment is preferably one that maintains high accuracy under an arbitrary set temperature condition in which the ambient temperature is in the range of 160 ° C to 230 ° C. For the heat treatment, the ambient temperature is in the range of 160 ° C to 230 ° C, more preferably 18
The range of 0 ° C. to 220 ° C. is preferable for imparting self-stretchability to the polyester multifilament undrawn yarn. If the atmospheric temperature is in the range of less than 160 ° C., a considerable amount of residence time is required to impart self-stretchability to the undrawn yarn, which is not preferable from the viewpoint of productivity and cost. On the other hand, if the temperature exceeds 230 ° C., the unstretched yarn may be melted by the heat of the heater when the machine is stopped or when the yarn is hooked, and the frequency of start breakage increases, which is not a preferable condition.

The residence time of the non-contact type heater in the heat treatment is 0.05 to 0.2 seconds, more preferably 0.09 to
It is necessary to set it to 0.18 seconds. If the heat treatment time is less than 0.05 seconds, crystallization of the polyester multifilament undrawn yarn by heating can be suppressed as much as possible, but the shrinkage component cannot be sufficiently removed, and the undrawn yarn is not drawn. The relaxed heat treated yarn (A) of (1) shows virtually no self-elongation. Further, if it is retained for 0.2 seconds or more, the shrinkage component can be sufficiently removed, but on the contrary, crystallization is excessively promoted, and in addition, it is necessary to slow the processing speed in order to increase the retention time. It is hard to say that it is the optimum condition in consideration of productivity and the like.

In order to combine the relaxed heat treated yarn (A) of the polyester multifilament undrawn yarn and the polyester multifilament drawn yarn (B), alignment or mixed fiber, more specifically, air entanglement means using a high pressure air flow at room temperature To use. The nozzle used for the air entanglement treatment is JP-B-36-1.
In addition to the well-known interlaced nozzle as seen in Japanese Patent No. 2230, a Taslan nozzle that forms a loop or a slack by a disturbing air flow can be used. When forming a minute loop or slack using a Taslan nozzle, etc., it may be wound onto the package after applying an appropriate amount of synthetic fiber coning oil for suppressing unwindability of the wound package. desirable. When the interlaced nozzle is used for the mixed fiber treatment, the number of entangled fibers per 1 m of the composite yarn is about 20 to 100 / m, and there are few problems such as yarn cracks in the subsequent process, and the viewpoint of process passability. Seems to be more suitable.

For example, the combination ratio of the relaxation heat treated yarn (A) and the polyester multifilament drawn yarn (B) of the polyester multifilament undrawn yarn constituting the polyester multifilament composite yarn obtained by the present invention is Although it can be appropriately selected according to the purpose, it is necessary that at least the relaxation heat treated yarn (A) yarn side does not cut 20%, and in consideration of the texture of the woven or knitted fabric,
The ratio of relaxed heat treated yarn (A) and drawn yarn (B) is 45/55
It seems that about 70/30 is preferable, but it is not limited to this.

The polyester multifilament composite yarn thus obtained is twisted, then low-temperature twisting set or low-temperature sizing is performed, and then woven and knitted to obtain a woven or knitted product, which is heat-treated by ordinary post-processing or the like (110 ℃ ~ 200
C.), the relaxed heat-treated yarn (A) of the polyester multifilament undrawn yarn having self-extending property develops elongation, and it is possible to make a woven or knitted fabric satisfying a swelling feeling with a good texture, a soft feeling and a dry feeling. It becomes.

[0034]

EXAMPLES The present invention will be specifically described below with reference to examples. Of course, the present invention is not limited to the following examples. (Example 1) Polyester semi-dual round cross-section multi-filament highly oriented undrawn yarn 45 denier 18 filaments having a boiling water shrinkage (SHW) of 69% spun at a take-up speed of 3200 m / min. Non-contact type slit heater, relaxation rate 45%, residence time 0.1
Relaxation heat treatment was performed for 8 seconds. The highly oriented undrawn yarn after the relaxation heat treatment had a crystallinity (Xρ) of 14.08%, a temperature (Tα) showing a main dispersion by a dynamic viscoelastic method was 116.3 ° C., and a maximum value of a mechanical loss tangent [ (Tan δ) max] is 0.2833
Met. In addition, the dry heat shrinkage (SH
D) was -10.3%, and it was confirmed to show substantially self-elongation.

The highly oriented undrawn yarn after the relaxation heat treatment, that is, the polyester multifilament undrawn yarn in the present invention has a relaxation heat treatment yarn (A) and a boiling water shrinkage ratio (SHW) of 16
%, Dry heat shrinkage (SHD) at a dry heat of 160 ° C is 1
A polyester multi-filament composite yarn was obtained by air entanglement of 8.5% polyester semi-dal cross-section multi-filament drawn yarn 50 denier 10 filaments with a known interlace nozzle by a high pressure air flow at room temperature. The number of entangled yarns per 1 m of the composite yarn was 75 / m, and the yarn was free from yarn cracks and had excellent handleability.

A double twister (No. 310-C manufactured by Murata Machinery Co., Ltd.)
At the ambient temperature of 6 after twisting 1800 T / m with
Twist stop setting was performed with a vacuum heat setter at 5 ° C. for 40 minutes. The composite yarn twisted yarn was used for both warp and weft and woven into a satin design having a greige density of 143 warps / inch and 94 wefts / inch. Then, a usual dyeing treatment was applied to obtain a dyed cloth having a finishing density of 160 warps / inch and 112 wefts / inch.
It was possible to obtain a cashmere-like woven fabric having an entirely new type of texture, which had an appropriate texture and a feeling of waist.

Comparative Example 1 A polyester multifilament drawn yarn (B) has a boiling water shrinkage (SHW) of 2.0.
%, Dry heat shrinkage (SHD) at a dry heat of 160 ° C. of 5.
A dyed cloth was obtained in the same manner as in Example 1 except that 50% denier filament of polyester semi-dull round cross-section multifilament drawn yarn of 5% was used. Although the dyed fabric had a soft feel and a dry feel, it lacked warmth and swelling, and was not suitable as a texture.

[0038]

The polyester multifilament composite yarn obtained according to the present invention is a composite yarn obtained by combining the relaxation heat-treated yarn of the polyester multifilament unstretched yarn having the self-stretching ability and the polyester multifilament stretched yarn. A composite yarn made of polyester multifilament suitable for women's clothing, which satisfies both soft and dry feels to the knitted fabric, and has a completely new texture with moderate swelling and swelling, and a feeling of waist. is there.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-2-307930 (JP, A) JP-A-3-8824 (JP, A) JP-A-8-60471 (JP, A) JP-A-4- 100936 (JP, A) JP 4-333634 (JP, A) JP 6-116828 (JP, A) JP 58-13751 (JP, A) JP 6-228821 (JP, A) JP-A-2-53926 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) D02G 1/18 D01F 6/62 D02G 3/04 D02J 1/00

Claims (3)

(57) [Claims] 1. A spinning take-up speed of 2000 to 4000 m / m.
The non-contact heat treatment is performed under the condition that the ambient temperature is 160 ° C to 230 ° C without substantially stretching the polyester multifilament undrawn yarn having a boiling water shrinkage (SHW) of 50% or more spun in. The temperature at which the crystallinity (Xρ) is 20% or less, the dry heat shrinkage ratio (SHD) at dry heat of 160 ° C. is less than 0%, and the main dispersion is obtained by the dynamic viscoelastic method is performed for 05 to 0.2 seconds. Polyester multifilament unstretched yarn having (Tα) of 90 ° C or higher and 125 ° C or lower and [(Tanδ) max] showing the maximum value of mechanical loss tangent of 0.20 or higher and 0.30 or lower is used as a relaxed heat treated yarn, and boiling water is used. Align both polyester multifilament drawn yarns with shrinkage (SHW) of 5.0% to 60% and dry heat shrinkage (SHD) at dry heat of 160 ° C of 7.0% to 80%. Or mixed and compounded A method for producing a polyester multifilament composite yarn, comprising: 2. A process for producing a polyester multifilament composite yarn of claim 1, wherein the mixed fiber means is air exchange fault means using ambient temperature of the high pressure air stream. 3. A process for producing a polyester multifilament composite yarn of claim 1, wherein the high pressure air flow to be used for air exchange fault means a disturbance airflow.