JPH02307930A - Conjugate polyester-based yarn - Google Patents

Abstract

PURPOSE:To obtain the subject rolling conjugate yarn capable of exhibiting soft and pliant touch by interlacing multifilament yarn containing a micropore- forming agent with multifilament yarn having a prescribed value or above of breaking strength and hot water shrinkage and dry heat shrinkage factors within specific ranges. CONSTITUTION:The objective conjugate yarn, composed of (A) 10-80% (denier ratio in the conjugate yarn) multifilament yarn, containing 0.5-5wt.% micropore- forming agent and having <=3de single filament size, >=0% hot water shrinkage factor (SHW) at 100 deg.C and <=0% dry heat shrinkage factor (SHD) at 160 deg.C and (B) 90-20% multifilament yarn having >=4g/d breaking strength, >=0% SHW and >=5% difference [SHD of the component (B) - SHD of the component (A)] and obtained by interlacing the components at 20-100 interlacements/m interlacing degree.

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention provides a micro-powder touch, that is, a soft, flexible and plump touch that has a cute touch, moderate firmness, firmness, and is mild. The present invention relates to a novel polyester composite yarn having deep luster and color tone.

(Prior Art) Polyester multifilaments have been used for various purposes such as clothing and industrial materials due to their excellent properties. Various companies have been considering silk-like texture as one of the targets for clothing applications. For this purpose, for example, a composite yarn consisting of multiple multifilaments with different heat shrinkage properties is swollen.
It has very good characteristics and texture, such as bulkiness and warm feel, and is widely used. If all of the multifilaments that make up the yarn shrink due to heat, due to the constraining force of the fabric structure, the difference in shrinkage rate of the threads cannot be maintained sufficiently, and the fabric becomes stiff due to the shrinkage of the threads. Therefore, countermeasures have been taken, such as reducing the basis weight to allow for shrinkage, and increasing the alkali weight loss rate to maintain the texture. However, filaments with a high heat shrinkage rate generally harden when heat treated, and a fully satisfactory texture has not been obtained. On the other hand, mixed yarns made of polyester filaments that are elongated and filaments that are shrunk by heat treatment are also known;
240, JP-A-56-112537, and JP-A-60-28515. Although these yarns had a much softer and more flexible texture than the above-mentioned shrink yarns, the loops made of elongated and protruding filaments gave a slimy feel, and heat treatment caused large yarn length differences. As a result, the threads separate, causing problems in handling in subsequent processes.

Furthermore, in JP-A No. 59-228014, kaolinite is added to polyester as a micropore-forming agent on the fiber surface, and the filament yarn knitted fabric is subjected to alkali weight loss treatment to improve the fiber surface and achieve silk-like luster and bend recovery. Methods have been proposed to improve performance and tactile sensation, but although they improve surface touch and gloss, they are insufficient in terms of softness, flexibility, and bulge.

(Problems to be Solved by the Invention) The second invention provides a soft, rolling micro-powder touch and a warm, natural dryness that can only be expressed with polyester, which could not be achieved with conventional technology. The purpose of the present invention is to provide a novel polyester-based composite yarn that is hand-stretched, firm, and has mild luster and color tone.

(Means for Solving the Problems) The present invention has the following configuration in order to solve the problems. That is, it is a composite yarn composed of multifilament yarn A and multifilament yarn B whose yarn physical properties satisfy the following range, and the composite yarn has an entanglement degree of 20 to 20.
A polyester composite yarn characterized by being intertwined at 100 threads/m.

Multifilament yarn A: Multifilament with a single yarn of 3 deniers or less containing 0.5 to 5% by weight of a micropore forming agent (?J [content rate of dowel tea towel 10 to 80% [denier ratio]) Multifilament B: Multifilament with a breaking strength of 4 g/denier or more (?j!Content in doubling yarn 9
0-20% [denier ratio])... (B) SHW (A
)≧0% SHD (A)≦0%SHW (B)≧O% SHD (B)-SHD (A)≧5% The present invention will now be described in more detail.

FIG. 1 is a model diagram after the polyester composite yarn of the present invention is heat-treated to develop a yarn length difference.

In FIG. 1, multifilament A mainly constitutes a sheath portion, and has been substantially elongated by high-temperature heat treatment (multifilament after spontaneous elongation).

Multifilament B mainly constitutes a core portion and is a multifilament that has been shrunk by heat treatment (multifilament after heat shrinkage).

First, the heat shrinkage characteristics of the constituent multifilament, which is the most important requirement of the present invention, will be discussed. Multifilament A constituting the polyester composite yarn of the present invention has a small shrinkage rate difference with multifilament B during normal sizing and other processes, and shows substantial shrinkage behavior. For this reason, even though yarn length differences occur in the fabric, yarn length differences (bulges, loops, etc.) do not occur much even when sizing is performed at the yarn stage, and even compared to ordinary differentially shrinkable mixed fiber yarns that are completely heat-shrinkable. During weaving, handling and weaving properties are much better. That is, if a yarn length difference (loop) occurs in the yarn state, the loops will naturally rub against each other during beaming, weaving, etc. and get caught in guides, combs, etc., or the opening will be poor, resulting in a significant reduction in process passability. Furthermore, when ordinary heat-shrinkable multifilament is heat-treated during sizing, etc., the heat-sealing property is almost fixed, and even if it is heat-treated at a high temperature of 160 to 180℃ during final setting, the yarn length difference will be greater than that at the first heat-setting. Although this does not occur much, like the composite yarn of the present invention, it contains multifilaments that shrink in hot water but elongate when subjected to high-temperature heat treatment equivalent to final set. Multifilament A protrudes in a loop shape and rolls around like micropowder, providing a soft and flexible touch.

For this reason, SHW (A) ≧ 0%, SHD (A) 50
% is required. Further, in order to provide swelling and bulkiness, SHD (B) -5HD (A) ≧5% is required, and if it is less than 5%, swelling and bulkiness are poor and it is excluded from the present invention. If it is too large, the protruding loop from the surface will be too large, which can easily cause problems such as 'shininess' when ironing, so it is preferable to use 50V6 or less.For the same reason, SHW (A) should be 5% or less, and SHD (A) should be 5% or less. )
is preferably -15% or more.

Next, at least the multifilament A must contain 0.5 to 5.0% by weight of a micropore forming agent.

That is, by including a micropore-forming agent, preferably kaolinite, metakaolin, etc., which will be described later, reflected light and transmitted light are combined in a complex manner, and a new mild and deep lustrous color tone effect can be obtained.

In particular, polyethylene terephthalate has a refractive index of 1.535 in the fiber cross-sectional direction and a refractive index of 1.725 in the fiber axial direction.
Depending on the direction in which the knitted fabric with 56 kaolinite added is viewed, a subtle deep luster can be obtained.

Next, if the amount of the micropore-forming agent added is less than 0.5% by weight, deep dyeing performance cannot be obtained, resulting in strong glare similar to what is called normal bright yarn. If it exceeds 5.0% by weight, the spinning properties in the spinning and drawing process may deteriorate,
This is not preferable because the strength of the filament yarn decreases.

Addition of such a micropore-forming agent makes it possible to obtain micropores on the fiber surface by performing an alkali weight reduction treatment in the form of yarn or fabric after it is made into fibers.

Next, the elongation at break of the multifilament A is preferably 50% or more, in order to obtain a soft and flexible texture.

Generally, in order to obtain a soft feel with polyester, it is easier to obtain a filament with a small SHW and a large elongation at break. As described in detail above, it is the spontaneously elongated multifilaments that form loops and cover the surface of the fabric, and the touch of these multifilaments determines the touch of the fabric. However, if the elongation at break is too large, the handling properties will deteriorate, so it should be less than 100%, more preferably 8
0% or less is good.

Note that the multifilament A may contain filament groups other than the filament group containing the micropore-forming agent.

Next, it is preferable that the elongation at break of the multifilament B is 40% or less, in order to prevent yarn unevenness due to elongation of the composite yarn in subsequent processes such as winding, weaving, knitting and weaving.

Furthermore, this is to prevent problems such as the knees coming off in the product after it has been made into a fabric. Furthermore, since the breaking strength of the composite yarn is also substantially dependent on the heat-shrinkable multifilament, the breaking strength of the multifilament B must be at least 4 g/denier and at least 20% of the denier ratio of the composite yarn.

Of course, if the breaking strength is high, the proportion of multifilament B may be slightly paper (but if it is less than 20%, the shrinkage force of multifilament B will be small and the bulge due to the difference in yarn length will not be expressed, so it is excluded from the present invention. The hot water shrinkage rate and the 160°C dry heat shrinkage rate of multifilament B are preferably 5 to 60% and 7 to 80%, respectively.Next, multifilament A is composed of single yarn denier of 3 deniers or less. It is necessary to If it exceeds 3 denier, the elongation at break is large and the texture becomes rough and hard even if the Young's modulus is low, so it is excluded from the present invention. However, if the filament becomes too thin, even if it is made into a filament with an irregular cross section, which will be described later, there will be no tension, so the thickness is preferably 0.2 denier or more. However, 3
The filament may contain filaments of 1 denier or more ((denier mix), but it is sufficient if the average denier is 3 denier or less.Furthermore, the filament preferably has an irregular cross section having at least one concave portion on the outer peripheral surface of the cross section.

In particular, filaments with a high breaking elongation such as the composite yarn of the present invention tend to feel soft or slimy, so by making the cross-sectional shape irregular, the number of point contacts between the filaments increases.
This results in a soft, dry touch. The irregular cross section referred to here refers to a triangular, hexagonal, oblate, hollow, etc. cross-sectional shape with a small (one concave part) on the outer circumferential surface of the cross section, and is representative of the cross-sectional shape of the single filament A used in the present invention. An example is shown in Fig. 3.In order to provide such a texture and effect, it is preferable that the fiber is composed of ten or more filaments of these single yarns.

Next, it is preferred that the composite yarn has a substantially core/sheath structure. That is, since a large amount of multifilament A exists in the surface layer of the composite yarn, the loops tend to protrude from the surface of the fabric. Furthermore, the phrase "substantially having a core/sheath structure" as used herein means only a structure in which the composite yarn is divided into a core part and a sheath part, that is, multifilament B and multifilament A, at the interface. Rather, the same components are mixed throughout the composite yarn, especially near the boundary surface, meaning that multifilament B is mainly spontaneously arranged in the core, and multifilament A is mainly arranged in the sheath.

The core/sheath structure and the denier ratio described above are measured by fixing the composite yarn with epoxy resin, cutting the cross-section randomly 100 times, observing it with an optical microscope, and determining the average value and rod shape from this. . It is also essential that they are entangled with a degree of entanglement of 20 to 100. When the degree of entanglement is less than 20, the multifilaments tend to separate from each other due to the difference in yarn length, which significantly impedes processability.

On the other hand, if the degree of entanglement exceeds 100, interlace spots will be noticeable on the fabric, and the monofilaments of multifilament A may be cut and become fluffy, which is not preferable.

Next, kaolinite, which is particularly preferable as a micropore-forming agent of the present invention, will be explained.

It is particularly preferable that the particle size of kaolinite has a particle size distribution in which the sum of particles having a spherical diameter equal to or greater than IPR, expressed as a particle size distribution of equivalent spherical diameter measured by a centrifugal sedimentation method or the like, is 10% or less. If the proportion of IIJJI particles exceeds 10%, the coarse particles in the polymer will clog the filter during spinning, resulting in a high rate of increase in the back pressure of the spinning nozzle (and a decrease in spinning operation efficiency, which is undesirable. When using kaolinite exceeding 1%, coarse particles of 1 or more should be separated as much as possible by centrifugation or the like.

Next, among the polyester composite yarns of the present invention, the cross section of at least multifilament A has a hollowness ratio of 4% or more and 30%
It is preferable that the hollow cross section is less than or equal to %. It is thought that the bending properties of the fibers change by making the cross section of the filament hollow, but it is possible to obtain a fiber with excellent bending elasticity. It will be bulkier than the original one. This, on the contrary,
This means that the knitted fabric with a hollow cross section is lighter than one without a hollow part even if the bulkiness is the same.

In order to have this effect, the hollowness ratio must be at least 4%; if it is less than 4%, only a material that is substantially the same as a solid material can be obtained. However, if the hollowness ratio exceeds 30%, unevenness is likely to occur during processes such as spinning and stretching, and thread breakage is also likely to occur, which is not preferable.

The hollowness ratio here is defined as Q, /Q, and
The value expressed in 100 (%) is called the hollowness ratio.

The filament can be applied to either a round cross section or a multi-lobed cross section as to the outer peripheral shape.

Next, among the polyester composite yarns of the present invention, some of the multifilaments (A) develop micropores on the fiber surface by alkali weight reduction treatment, and the micropores have a vertical length in the fiber axis direction. Yes (a) The maximum value of the frequency distribution of the maximum width is 0.7u or less, (a) The average value of the length/R width ratio is 3 or less, and (c) The number of fathoms is 100 μI on the fiber surface.
There are an average of 30 or less pieces per hole, and (d) 60% or more of the total depth is 0.1- or less.

The length of the micropores (length in the direction of the fiber axis) and width (length in the direction perpendicular to the fiber axis) are determined from the measured values of 100 or more micropores from a side photograph of a scanning electron microscope at a magnification of 5000 times. . In addition, the depth of the micropores was determined by cutting the sample filament embedded in acrylic resin into multiple sections with a thickness of 4μ, and eluting the acrylic resin from the sections with isoaluminum acetate.
From an electron micrograph with a magnification of 10,000 times, draw a tangent line between adjacent convexities and measure the distance between the tangent line and the lowest surface of the concave part.
Obtained as the average value of 00 or more.

When the size of the micropores is measured by such a method, at least multifilament A is characterized by the presence of micropores that satisfy the four requirements (a), (0), (c), and (d) above. be.

Regarding the maximum width of such micropores, the maximum frequency value exists below the 0.7μ layer. It is desirable that it exists in the range of 0.2 to 0.7-.

If this maximum value exceeds 0.7-, the effect on the tactile sensation is halved, and especially when deep colors are used, the pastel tone that appears whitish becomes too strong.

When the average value of the (length/maximum width) ratio of micropores is larger than 3, there will be a difference in gloss when viewed from a direction perpendicular to the fiber axis and when viewed from a direction parallel to the fiber axis, resulting in a fabric that is orthogonal to the weft and weft. If this is done, the gloss will become irritating. On the other hand, if the average value of the ratio (length/maximum width) is 3 or less, there will be less irritation (good gloss).

It is also necessary that the number of micropores be on average 30 or less per 100 microns on the fiber surface, and more preferably in the range of 10 to 30. If the number exceeds 30, the luster will become whitish (the pastel tone will become too strong).If the number of micropores with a depth of more than 0.1 exceeds 40% of the total, the luster will become dull, with a deep shine. The luster is lost.

In addition, if the maximum depth of micropores exceeds 0.41 JJ, the pastel tone of the dyed product will not only be emphasized, but also the strength of the filament yarn will decrease, and the practical performance of the knitted fabric will deteriorate due to filament breakage. This is not preferable because it lowers the temperature.

Next, the cross section of multifilament B, which mainly constitutes the inner layer part, is not particularly limited, but hollow fibers may be used to provide bulkiness, and fine pore-forming agents may be used as in multifilament A to further improve the dry hand. It is also preferable to use a thread having an irregular cross section and having at least one concave portion on the outer circumferential surface of the cross section.

Furthermore, in the polyester composite yarn of the present invention, multifilament A component and multifilament B component that differ in dyeability, color tone, etc. may be combined.

Next, it is also preferable that the present composite yarn is in a heated state.

However, if the yarn is twisted too strongly, it is difficult to create a difference in yarn length, so 15
000/'″D (T/m) or less is preferable, but soft;
It is not necessarily limited to this when flexibility is not required or when a grain effect is to be expressed.

Next, a method for manufacturing the polyester composite yarn of the present invention will be explained.

A schematic side view of the apparatus for producing polyester composite yarn of the present invention is illustrated in FIG. To produce polyester multifilament A with excellent spontaneous elongation, a polymer polymerized by a conventional method containing a micropore-forming agent, preferably 0.5 to 5% kaolinite, is spun at a spinning speed of 1500 to 4000 m/min. Spinning. Then, the main end drawn yarn is stretched at a temperature of Tg - Tg + 20°C.
and elongation at break after stretching 30-45%, Δno, 10-0
．． Stretch it to a length of 14. Here, the stretching temperature should be at least 7 degrees Tg for stretching stability, but temperatures higher than Tg + 20°C are not preferred because crystallization progresses and spontaneous elongation property decreases.

Next, a relaxing heat treatment is performed to give spontaneous elongation, but the overfeed and temperature at this time can be selected as appropriate depending on the required elongation, but the overfeed is 20~20°C.
60%, and the temperature is preferably about 150 to 230°C.

In this case, a non-contact heater is preferable since the heater has a large overfeed rate.

Next, this polyester multifilament A is intertwined with polyester multifilament B, which has at least different heat shrinkage characteristics, so that the denier ratio is 10 to 80%/90 to 20% at an entangling degree of 20 to 100 f/m. . The entangling device may be an ordinary interlacer using air, but since fuzz is likely to occur due to the combination of multifilaments A1B, it is preferable to use a thread passage with a small surface roughness, particularly one with a surface roughness of 38 or less. The conditions for the entangling treatment may be selected as appropriate depending on the degree of entanglement required, but the air pressure should be 2 to 10 kg/crl! G1 overfeed rate is O
The preferred range is 0.8%.

Next, the polyester composite yarn is preferably twisted and then set and/or glued at 85°C or less,
After drying, it is woven as the warp and/or weft of a fabric. The reason for twisting is that this polyester composite yarn has a difference in dyeability between spontaneously elongated yarns and shrinkable yarns, so if they are simply intertwined, hair unevenness and unevenness will easily occur due to the difference in dyeing, and the spontaneously elongated yarns will be irregular. This is because the surface of the fabric becomes irregular and the quality deteriorates, and when tension is applied during the warping, gluing, and weaving processes, the degree of entanglement decreases and loops occur frequently, reducing weavability. .

For this purpose, it is sufficient for the number of additional twists to be 1,100≦ to ≦6,000, but in the case of a strong twist type, it may be selected as appropriate depending on the application. Here, the number of additional twists (T/m) = /'? S [This is the denier of the doubling yarn.

Next, setting is performed, but the number of additional twists is 1100≦≦600
If the number of twists is 0, gluing and drying may be performed, and if the number of additional twists is K>6000, twist setting may be performed.

However, in both cases, it is preferable that the maximum temperature is 85°C or less.

Further, it is preferable that the twist set is 70″C or less.This is for the following reason.

■ The high-temperature dry heat treatment during sizing advances the crystallization of the fibers, reducing the spontaneous elongation that should be achieved during the dyeing process.
Fabrics with sufficient fullness cannot be obtained.

■ Differences in yarn length occur due to high-temperature dry heat treatment during sizing, resulting in poor weavability.

Further, the temperature for gluing is preferably room ifA to 50°C, and the temperature for drying is preferably 75°C or less, and a normal acrylic solid for filaments can be used as the sizing agent. The sizing machines used are a cylinder type manufactured by Tsudakoma and a type manufactured by Kawamoto Seiki.
The chamber is around 70'C and the second chamber is 75'C.
The draft inside the chamber should be as low as 0.1 at the front and rear.
~0.2 g/d is preferred.

Of course, methods other than the above-mentioned method may be used as long as they have a low-temperature cent effect.

The thus obtained composite multifilament is woven into warp and/or weft yarns by a conventional method, but shuttleless weaving such as water jut loom is preferred. This is because in shuttle looms, fluff tends to occur while the shuttle is flying.

By heat-treating the woven fabric thus obtained (at 110 to 200° C.) in a normal post-processing process, the spontaneously elongated yarn components are elongated, resulting in a soft-touch woven fabric with good texture and fullness.

In particular, by carrying out alkali weight loss of 10 to 40%, preferably 15 to 35%, vertically long micropores are generated in the direction of the fiber axis, resulting in a supple touch, deep color tone, and gloss.

Next, the configuration and effects of the present invention will be explained in more detail with reference to the following examples, but the present invention is not limited by the following examples.

(Example) Note that the measurement method implemented in the present invention is as follows.

(1) Elongation at break According to J15-L-1013 (1981), sample length (gauge length) was determined using Tensilon manufactured by Toyo Baldwin Co., Ltd.
200. The S-8 curve was measured at a tensile speed of 200 m/min, and the elongation at break was calculated.

■ Heat shrinkage rate (SHW), dry heat shrinkage rate (SHD)
According to 5-L-1073, the following was carried out.

That is, take a skein that has been wound eight times with an initial load of 1/10 g/denier using a wrap reel with an appropriate frame circumference, and apply a load of 1/30 g/denier to the skein to determine its quality. (.) to measure °. Then, the load was removed, and the skein was immersed in boiling water for 30 minutes with a load of 1/1000 g/denier applied. After that, remove the skein from the boiling water, cool it down, and then refill it by 1/3.
Applying a load of 0 g/denier, the length Q, (,,
) to measure.

Next, a cold is prepared under the same conditions and Qo (m11) is measured. Then, it is heat-treated in a dry heat oven at 160"C with a load of 1/1000 g/denier applied. Then, after cooling, a load of 1/30 g/denier is applied again to measure the previous length e2 (,,). Measure the hot water shrinkage rate (SH
W) and dry heat shrinkage (SHD) are calculated by the following formula.

(3) Degree of entanglement Take out a thread of appropriate length, apply a load of 1/log/denier to the lower end, and hang it vertically. Next, a suitable needle is inserted into the system, and the distance (! (am)) that the needle travels until the load is lifted is measured 100 times, and the average value Q(c-) is obtained from this and calculated using the following formula.

(Examples) The present invention will be described in detail below using Examples, but the present invention is not limited to these Examples.

(Examples 1, 2, Comparative Examples 1, 2, 3) Kaolinite (ASP-072 manufactured by Engelhard): 10% of coarse particles removed by centrifugation, refractive index 1.56, average particle size 0.
A polyester polymer consisting essentially of repeating only ethylene terephthalate, containing 2% by weight of 3μm and 11μm particles (1.5% by weight of TiO2 as an impurity in kaolin)) was spun and wound in a conventional manner. speed 30
After stretching and relaxing at 00 m/min, the spinning nozzle shape, spinning discharge amount, stretching ratio, relaxation ratio,
Obtained by changing the relaxing temperature and set time. The heat-shrinkable multifilament was commercially available from Toyobo Co., Ltd. and Toyobo Ester, and was processed using the stretching/relaxing machine shown in Figure 2.

Here, Air Jet FG-1 manufactured by Fiber Guide Co., Ltd. was used as the air nozzle 7, and the air pressure and the feed ratio between the feed roller 8 and the delivery roller 8 were adjusted so as to obtain the target degree of entanglement. The physical properties of the raw yarn used, the yarn quality of the obtained composite yarn, and the yarn twisted by the usual method.
After warping, use a sizing machine manufactured by Kawamura Seiki to apply a regular acrylic sizing agent for filaments.
After drying in a chamber at 75°C, weave the deshine and
% Arca 1Jfi,! After that, the texture of the dyed fabric was evaluated. In addition, as for process passability, particular evaluations were made regarding twisting, winding, and weaving properties, and the overall evaluations in terms of process passability, texture, color tone, and gloss are listed in Table 1.

Examples 1, 2, and 3 had good texture, processability, and color gloss within the scope of the present invention, and Example 3 was particularly excellent in terms of elasticity and bulk.

Comparative Example 1 had a small amount of pore-forming agent, so even after the alkali reduction process, it had a slimy feel and was not good in terms of texture and color tone and gloss.

Comparative Example 2 contained too much pore-forming agent, had many thread breaks during spinning and drawing, had too strong a dull feel, and was poor in color tone and gloss.

Comparative Example 3 was a heat-stretchable multifilament 1-A, which stretched even at low temperatures, produced loops after sizing, and had problems in passing through the process.

In Comparative Example 4, both multifilaments A and B shrunk, and the texture was the same as that of a normal differentially shrinkable mixed fiber yarn, without the micropowder effect of the present invention, and was poor.

Comparative Example 5 had a small ΔSHD, so it did not bulge and had a feel that was not much different from normal flant yarn.

In Comparative Example 6, since the breaking strength of multifilament B was low, the strength of the composite yarn was also low, and thread breakage occurred frequently in subsequent processes, particularly in the twisting and weaving processes.

In Comparative Example 7, the proportion of multifilament B was too large, so the texture effect of the self-extensible yarn was small.

On the contrary, in Comparative Example 8, the ratio of multifilament B was too small, the strength of the composite yarn was low, and as in Comparative Example 6, thread breakage occurred frequently in the subsequent process.

In Comparative Example 9, the degree of entanglement was low, so thread breakage occurred frequently during twisting and winding. On the other hand, in Comparative Example 10, there was no problem in process passability, but moiré spots occurred when the number of heating was small.

In addition, due to alkali weight loss, multifilament A is compared to Comparative Example 1.
Almost no micropores were generated, and as mentioned above, the product had a strong slimy feel. However, in Comparative Example 2, when the alkali weight loss was carried out by 15 to 30% of the normal amount, the depth and length of the micropores decreased [1]
, the number of pieces increased, and there were also problems in terms of the physical properties of the fabric.

(Effect of the invention) As described above, the polyester composite yarn of the present invention is softer, more flexible, has a 1-1 dry touch, and has a moderate amount of firmness than conventional mixed cotton fiber yarns (including heat-stretched yarns). It has the remarkable effects of having good elasticity, drapability, excellent RT color tone and gloss, and excellent permeability.

[Brief explanation of drawings]

FIG. 1 is a model diagram of the polyester composite yarn of the present invention heat-treated to develop a yarn length difference. FIG. 2 is a schematic side view showing an example of the manufacturing apparatus. FIG. 3 shows a typical example of the cross-sectional shape of the multifilament A of the present invention. A: Heat-stretched multifilament B: Heat-shrinkable multifilament C: Polyester composite yarn of the present invention 3: Hot roller 5: Non-contact heater 7: Air gradient nozzle ° field 11! I A: 9 total 3i long i branch Q multi-fifmen h' r3:
z Now〃nu, IIArx's 71,000 filaments exhausted 2 Figure 7: Air, >'x 71' 1 Shihoma 3 N! ! ”

Claims (1)

[Claims] (1) A composite yarn composed of multifilament yarn A and multifilament yarn B whose yarn physical properties satisfy the following range, and the composite yarn has an entanglement degree of 20 to 100 threads/m
A polyester composite yarn characterized by being intertwined with each other. Multifilament yarn A: Multifilament with a single yarn of 3 denier or less containing 0.5 to 5% by weight of a micropore forming agent (content rate in the composite yarn: 10 to 80% [denier ratio]) Multifilament B: Breaking strength is 4g/denier or more (content in the composite yarn is 90~
20% [denier ratio])...(B) SHW(A)≧0% SHD(A)≦0% SHW(B)≧0% SHD(B)-SHD(A)≧5% SHW: Hot water (100 ℃) Shrinkage rate (%) SHD: Dry heat (160℃) Shrinkage rate (%)