KR20160094836A - Bicomponent conjugate fibers, complex yarns and fabrics having high crimping property - Google Patents

Abstract

The present invention relates to a bicomponent complex fiber having excellent crimping properties, which comprises: (A) a thermoplastic polyester elastic polymer (TPEE) as a first component; and (B) a polyester polymer as a second ingredient. In addition, the present invention relates to a yarn and a fabric comprising the bicomponent complex fiber.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a bicomponent composite fiber, a composite yarn and a fabric having high crimp characteristics,

The present invention relates to a bicomponent conjugate fiber having excellent crimp properties comprising (A) a thermoplastic polyester elastomer (TPEE) as a first component, and (B) a polyester polymer as a second component . The present invention also relates to yarns and fabrics comprising the bicomponent composite fibers.

The self-crimping properties of the conjugate fibers can be created primarily from the process of making side-by-side bicomponent fibers. Because of the different intrinsic viscosities (IV) between the two polymers forming the conjugate fibers, the two polymers have different shrinkage causing three-dimensional crimp of the fibers. The self-crimping properties are the crimp potential which inevitably occurs due to the amount of shrinkage of the two polymers, the degree of shrinkage and the difference in elastic modulus. In addition to the difference in shrinkage as a precondition for the self-crimping properties, good adhesion must be present between the two polymers. However, it is not absolutely necessary to utilize a different polymer because shrinkage differences can also be caused by differences in orientation, crystallinity or relative viscosity. Generally, the shrinkage differences of the polymers produced by the same material are similar, so it is not easy to produce high shrinkage that suits the requirement of high elasticity. For example, Japanese Patent Application No. 2001-226832 uses a polyethylene terephthalate (PET) material having different intrinsic viscosities for the production of high crimped bicomponent composite fibers (in this patent application example, an intrinsic viscosity of 0.53 dl / g ≪ / RTI > PET with an intrinsic viscosity of 0.76 dl / However, the CI (crimp index, i.e., elasticity index) of the fiber produced by the above method is unsatisfactory.

The main object of the present invention is to provide a bicomponent composite fiber having high crimp properties and excellent elasticity.

In one aspect of the present invention, the present invention relates to a bicomponent composite fiber having excellent crimp properties comprising (A) a thermoplastic polyester elastomer (TPEE) as a first component, and (B) a polyester polymer as a second component Wherein the weight ratio of the thermoplastic polyester elastomer (TPEE) as the first component to the polyester polymer as the second component is 20:80 to 80:20, preferably 30:70 to 70:30, most preferably Is in the range of 40:60 to 60:40.

The molecular structure of the thermoplastic polyester elastomer is composed of two parts: a rigid segment and a soft segment, wherein the rigid segment is an aromatic polyester such as poly (ethylene terephthalate) (PET) or polybutylene terephthalate PBT), and the soft segment is a polyether ester.

In one embodiment of the present invention, (A) the thermoplastic polyester elastomer as the first component is a thermoplastic elastomeric composition wherein the hard segment is a polyester such as PET or PBT and the soft segment is a polyetherester such as polytetramethylene ether glycol ), Wherein the weight ratio of the hard segment to the soft segment is in the range of 80:20 to 20:80, and the number average molecular weight of the polyether glycol is in the range of 500 to 5,000.

If the viscosity of the thermoplastic polyester elastomer is less than 0.5 dl / g, the yield of fiber production is poor and its physical properties are poor. If the viscosity of the thermoplastic polyester elastomer is more than 2.4 dl / g, the fluidity of the polymer is poor and the melting point during the manufacturing process must be increased, and therefore, the polymer tends to decompose and exhibit bad production yield. Therefore, in one embodiment of the present invention, the thermoplastic polyester elastomer as the first component has a density of 0.5 to 2.4 dl / g, preferably 0.8 to 2.2 dl / g, most preferably 1.1 to 1.9 dl / g And has an intrinsic viscosity of the range.

If the viscosity of the polyester polymer is less than 0.45 dl / g, the yield of the fiber is poor and its physical properties are poor. When the viscosity of the polyester polymer exceeds 1.2 dl / g, the fluidity of the polymer is poor and the melting point during the manufacturing process must be increased, and therefore, the polymer is decomposed and is liable to exhibit poor production yield. Therefore, in one embodiment of the present invention, the polyester polymer as the second component has a density in the range of 0.45 to 1.2 dl / g, preferably 0.45 to 0.85 dl / g, and most preferably 0.45 to 0.70 dl / g And has an intrinsic viscosity.

In another aspect of the present invention, the present invention relates to a method for producing a bicomponent composite fiber that can be performed utilizing a single step direct spin-drawing process. The method is characterized in that the first component and the second component as the spinning material are heated at a temperature of 220 to 300 DEG C respectively (for example, a PBT-type TPEE A temperature of 220 to 290 [deg.] C can be selected, and a temperature of 280 to 300 [deg.] C can be selected when PET-type TPEE is used) And spinning from a spinneret. After cooling and oiling, spinning and stretching are carried out at a spinning speed of 1000 to 6000 m / min, a draw ratio of 1.0 to 10, a draw temperature of 20 to 100 ° C, and a heat setting temperature of 20 to 200 ° C , High crimp two component fully drawn yarn (FDY) or highly oriented yarn (HOY).

In a further embodiment, the bicomponent composite fibers of the present invention may also be prepared utilizing post-spinning or false-twist texturing of a multistage process. The method comprises the steps of providing a first component and a second component as a spinning material, at a temperature of 220 to 300 DEG C, depending on the type of said material as the first component and the second component (for example, a PBT-type TPEE A temperature of 220 to 290 [deg.] C may be selected if used, and a temperature of 280 to 300 [deg.] C may be selected if PET-type TPEE is used) And radiating. After cooling and oiling, coiling is carried out at a spinning speed of 500 to 6000 m / min, followed by a stretching process and stretch-twist texturing process for stretched texture yarns (DTY), or air for an air texture yarn (ATY) The twist texturing process is carried out at a process speed of 100 to 1200 m / min, a hot plate temperature of 70 to 220 캜, and a draw ratio of 1 to 10 to produce a high crimped two component fully drawn yarn (FDY) or textured yarn DTY or ATY).

In one embodiment, the thermoplastic polyester elastomer as the first component comprises a PET-type TPEE and a PBT-type TPEE, each of which is formed in a reaction scheme as shown below:

In the above reaction formula, the abbreviation mentioned has the following meaning:

TPA: terephthalic acid;

EG: ethylene glycol;

PTMEG: polytetramethylene ether glycol;

PET: polyethylene terephthalate;

TPEE: thermoplastic polyester elastomer; And

BDO: Butanediol.

The thermoplastic polyester elastomer (TPEE) used in the present invention has an intrinsic viscosity in the range of 0.5 to 2.4 dl / g, preferably 0.8 to 2.2 dl / g, and most preferably 1.1 to 1.9 dl / g.

In one embodiment, the polyester polymer (B) as the second component is selected from the group consisting of polyethylene terephthalate, polyethylene isoterephthalate, copolymers of polyethylene terephthalate / polyethylene isoterephthalate, polybutylene terephthalate, ) Polyesters, polybutylene succinates, environmentally recyclable polyesters, biomass polyesters, and thermoplastic polyester elastomers, wherein said environmentally recyclable polyester And biomass polyesters may be environmentally recyclable PET and biomass PET.

The polyester used in the present invention has an intrinsic viscosity in the range of 0.45 to 1.2 dl / g, preferably 0.45 to 0.85 dl / g, and most preferably 0.45 to 0.70 dl / g.

The bicomponent conjugate fiber of the present invention may be a parallel bicomponent conjugate fiber. That is, in the cross-sectional view of the composite fiber, the above-mentioned first component and second component are arranged in a parallel arrangement.

 The bicomponent conjugate fibers of the present invention may be in the form of continuous long filaments or short filaments.

The bicomponent composite fiber of the present invention may be in the form of a circular cross section or a non-circular cross section.

In another embodiment of the present invention, the method for producing a bicomponent conjugate fiber of the present invention may further comprise, if necessary, further functional additives such as a flame retardant, an insulating agent, an ultraviolet ray inhibitor, an antistatic agent, a fluorescent bleaching agent, matting agents and the like.

The bicomponent composite fibers described herein can be fibers of stretched textured yarn (DTY), air textured yarn (ATY), highly oriented yarn (HOY) or fully drawn yarn (FDY).

In another aspect, the invention relates to yarns and fibers made by the bicomponent composite fibers of the present invention.

On the basis of the parallel bicomponent composite fibers of the present invention, high crimped long filament products or short filament products can be produced as desired.

Based on the bicomponent conjugate fibers of the present invention, the conjugate fibers alone or additionally other fibers can be complexed to form a composite yarn.

The present invention is also capable of producing fibers by art-known fabric manufacturing techniques using bicomponent composite fibers produced by the above-mentioned production processes or composite fiber yarns comprising bicomponent composite fibers of the present invention .

The physical properties of the parallel bicomponent composite fibers of the present invention are determined by the method as described in detail below:

1. Intrinsic Viscosity (IV)

The intrinsic viscosity is determined by the method according to ASTM D2857-87. EXAMPLES AND COMPARATIVE EXAMPLES Each of the raw materials was dissolved to form a test solution. In a capillary Ubbelohde viscometer, the flow times of test solutions and pure solvents at various concentrations (0.1%, 0.2%, 0.3%, 0.4%, 0.5%) are respectively measured and the intrinsic viscosity of each test solution is determined . The intrinsic viscosity versus concentration is then plotted. The intrinsic viscosity in dl / g represents the viscosity when the concentration reaches 0%, calculated by extrapolation.

2. Fiber strength and elongation

The breaking strength and elongation of the fibers are measured with an automatic stretch tester, STATIMAT M.

3. Crimp index (CI)

Sample preparation: Fiber with the given fineness was wound on a winder including a filament winding section with a barrel around 1 m or 1.125 m . The crimp number of the fibers is calculated by the following method:

Number of crimp of fiber = 3500 ÷ Fineness

The experiment was performed after the oven was set at 120 ° C and held for 30 minutes.

· Wound on a winder Unscrew the fibers and attach them to the wall vertically. A weight of 10.5 g is placed on one end of the fiber, followed by a weight of 700 g on top of it. After 10 seconds, the length of the fiber is measured and recorded as L1.

700 g of the weight is removed from the fibers, and still 10.5 g of additional fibers are placed in an oven maintained at 120 ° C and allowed to dry for 5 minutes.

After drying, still take 10.5 g of additional fiber from the oven and hang it back on the wall for 2 hours to cool. At this point, the length of the fiber is measured and recorded as L2.

Add 700 g of weight to the fiber. At this point, the length of the fiber is measured and recorded as L3.

Calculate the crimp index (CI) based on the following formula:

CI% = [(L3 - L2) / (L2)] x 100%

Example

The following examples are intended to illustrate the technical details of the present invention and the effect to be achieved, but are not intended to limit the present invention. Any equivalent variations and modifications in accordance with the present invention are also within the scope of the present invention.

Example  One

The bicomponent composite fiber of Example 1 was prepared according to the method described below. Using a screw extruder, PBT-TYPE TPEE (first component) having an intrinsic viscosity of 1.8 dl / g was melted at a melting temperature of 250 캜 and PET (second component) having an intrinsic viscosity of 0.45 dl / g Melting at a melting temperature of 280 DEG C and then releasing them individually quantitatively. The first and second components were mixed in a weight ratio of 20:80 and then placed in a spinning cabinet at a spinning temperature of 285 ° C and subsequently extruded through the composite and parallel spinnerette assembly and cooled with cooling air , Followed by spinning and drawing at a spinning rate of 4000 m / min, a drawing temperature of 80 캜, a heat setting temperature of 140 캜, and a draw ratio of 2.1 to produce a 75/24 two component fully drawn yarn (FDY). The results of the fabricated fibers are shown in Table 1.

Example  2

The bicomponent composite fiber of Example 2 was prepared according to the preparation method described in Example 1 except that the weight ratio of the first component to the second component was replaced by 50:50. The results of the fabricated fibers are shown in Table 1.

Example  3

The bicomponent composite fiber of Example 3 was prepared according to the preparation method described in Example 1 except that the weight ratio of the first component to the second component was replaced by 80:20. The results of the fabricated fibers are shown in Table 1.

Example  4

The bicomponent conjugate fiber of Example 4 was prepared according to the preparation method described in Example 2 except that the second component was replaced by a cationic dyeable polyester (CD) having an intrinsic viscosity of 0.56 dl / g. The results of the fabricated fibers are shown in Table 1.

Comparative Example  One

The bicomponent composite fiber of Comparative Example 1 was prepared according to the preparation method described in Example 2 except that the first component was mixed with PET having a high intrinsic viscosity of 0.75 dl / g and the second component was mixed with a low intrinsic viscosity of 0.53 dl / g And replaced with PET having a viscosity. The results of the fabricated fibers are shown in Table 1.

The first component
(weight%) The second component
(weight%) Fiber strength
(g / d) Fiber elongation
(E%) Crimp index
(CI) Example 1 PBT-type
TPEE / 20 wt% PET / 80 wt% 4.2 33.1 66 Example 2 PBT-type
TPEE / 50 wt% PET / 50 wt% 4.3 35.1 80 Example 3 PBT-type
TPEE / 80 wt% PET / 20 wt% 3.5 34.8 80 Example 4 PBT-type
TPEE / 50 wt% CD / 50 wt% 3.7 36.8 63 Comparative Example 1 PET / 50 wt% PET / 50 wt% 3.7 33.0 5

Example  5

The bicomponent composite fiber of Example 5 was prepared according to the method described below. Using a screw extruder, a PBT-type TPEE (first component) having an intrinsic viscosity of 0.5 dl / g was melted at a melting temperature of 250 ° C and PET (second component) having an intrinsic viscosity of 0.45 dl / g Melting at a melting temperature of 280 DEG C and then releasing them individually quantitatively. The first component and the second component were mixed in a weight ratio of 50:50 and then placed in a spinning cabinet at a spinning temperature of 285 ° C and subsequently extruded through the composite and parallel spinnerette assembly and cooled with cooling air, (FDY) was prepared by spinning and drawing at a speed of 4000 m / min, a drawing temperature of 80 캜, a heat setting temperature of 140 캜, and a draw ratio of 2.1. The results of the fabricated fibers are shown in Table 2.

Example  6

The bicomponent composite fiber of Example 6 was prepared according to the method described below. Using a screw extruder, a PBT-type TPEE (first component) having an intrinsic viscosity of 2.4 dl / g was melted at a melting temperature of 250 ° C and PET (second component) having an intrinsic viscosity of 0.45 dl / g Melting at a melting temperature of 280 DEG C and then releasing them individually quantitatively. The first component and the second component were mixed in a weight ratio of 50:50 and then placed in a spinning cabinet at a spinning temperature of 285 ° C and subsequently extruded through the composite and parallel spinnerette assembly and cooled with cooling air, (FDY) was produced by spinning and drawing at a speed of 4000 m / min, a drawing temperature of 80 캜, a heat setting temperature of 140 캜 and a draw ratio of 2.1. The results of the fabricated fibers are shown in Table 2.

Comparative Example  2

The bicomponent composite fiber of Comparative Example 2 was prepared according to the preparation method described in Example 2 except that the first component was replaced with a PBT-type TPEE having an intrinsic viscosity of 0.45 dl / g. The results of the fabricated fibers are shown in Table 2.

Comparative Example  3

The bicomponent composite fiber of Comparative Example 3 was prepared according to the preparation method described in Example 2 except that the first component was replaced by a PBT-type TPEE having an intrinsic viscosity of 2.5 dl / g. The results of the fabricated fibers are shown in Table 2.

The first component
Intrinsic viscosity
(dl / g) The second component
Intrinsic viscosity
(dl / g) Fiber strength
(g / d) Fiber elongation
(E%) Crimp index
(CI) Example 2 1.8 0.45 4.3 35.1 80 Example 5 0.5 0.45 2.5 35.1 8 Example 6 2.4 0.45 4.5 35.1 82 Comparative Example 2 ^** 0.45 0.45 2.1 35.9 2 Comparative Example 3 ^* 2.5 0.45 4.5 37.8 85 * Poor manufacturing yield
** Poor manufacturing yield and poor physical properties

Example  7

The bicomponent composite fiber of Example 7 was prepared according to the method described below. Using a screw extruder, a PBT-type TPEE (first component) having an intrinsic viscosity of 1.8 dl / g was melted at a melting temperature of 250 ° C and PET (second component) having an intrinsic viscosity of 0.76 dl / g Melting at a melting temperature of 290 ° C, and then releasing them individually quantitatively. The first component and the second component were mixed in a weight ratio of 50:50 and then placed in a spinning cabinet at a spinning temperature of 285 ° C and subsequently extruded through the composite and parallel spinnerette assembly and cooled with cooling air, (FDY) was prepared by spinning and drawing at a speed of 4000 m / min, a stretching temperature of 80 캜, a heat setting temperature of 140 캜, and a draw ratio of 2.1. The results of the fabricated fibers are shown in Table 3.

Example  8

The bicomponent composite fiber of Example 8 was prepared according to the method described below. Using a screw extruder, a PBT-type TPEE (first component) having an intrinsic viscosity of 1.8 dl / g was melted at a melting temperature of 250 ° C and PET (second component) having an intrinsic viscosity of 1.0 dl / g Melting at a melting temperature of 295 DEG C, and then releasing them individually quantitatively. The first component and the second component were mixed in a weight ratio of 50:50 and then placed in a spinning cabinet at a spinning temperature of 285 ° C and subsequently extruded through the composite and parallel spinnerette assembly and cooled with cooling air, (FDY) was prepared by spinning and drawing at a speed of 4000 m / min, a stretching temperature of 80 캜, a heat setting temperature of 140 캜, and a draw ratio of 2.1. The results of the fabricated fibers are shown in Table 3.

Comparative Example  4

The bicomponent composite fiber of Comparative Example 4 was prepared according to the preparation method described in Example 2 except that the second component was replaced by PET having an intrinsic viscosity of 1.3 dl / g and melted at a melting temperature of 300 ° C. The results of the fabricated fibers are shown in Table 3.

The first component
Intrinsic viscosity
(dl / g) The second component
Intrinsic viscosity
(dl / g) Fiber strength
(g / d) Fiber elongation
(E%) Crimp index
(CI) Example 2 1.8 0.45 4.3 35.1 80 Example 7 1.8 0.76 4.4 33.5 47 Example 8 1.8 1.20 4.4 36.1 31 Comparative Example 4 ^* 1.8 1.30 4.5 36.9 15 * Poor manufacturing yield

Example  9

The bicomponent composite fiber of Example 9 was prepared according to the method described below. Using a screw extruder, a PBT-type TPEE (first component) having an intrinsic viscosity of 1.8 dl / g was melted at a melting temperature of 250 ° C and PET (second component) having an intrinsic viscosity of 0.45 dl / g Melting at a melting temperature of 280 DEG C and then releasing them individually quantitatively. The first component and the second component were mixed in a weight ratio of 50:50 and then placed in a spinning cabinet at a spinning temperature of 285 ° C and subsequently extruded through the composite and parallel spinnerette assembly and cooled with cooling air, Wound at a speed of 3000 m / min, and then subjected to an FDY stretching process at a processing speed of 500 m / min and a draw ratio of 1.8 to prepare a high-co-efficient two-component fully drawn yarn (FDY). The results of the fabricated fibers are shown in Table 4.

Example  10

The bicomponent composite fiber of Example 10 was prepared according to the method described below. Using a screw extruder, a PBT-type TPEE (first component) having an intrinsic viscosity of 1.8 dl / g was melted at a melting temperature of 250 ° C and PET (second component) having an intrinsic viscosity of 0.45 dl / g Melting at a melting temperature of 280 DEG C and then releasing them individually quantitatively. The first component and the second component were mixed in a weight ratio of 50:50 and then placed in a spinning cabinet at a spinning temperature of 285 ° C and subsequently extruded through the composite and parallel spinnerette assembly and cooled with cooling air, Twisted textured yarn (DTY) was prepared by winding at a speed of 3000 m / min, followed by a DTY twist texturing process at a processing speed of 500 m / min and a draw ratio of 1.8. The results of the fabricated fibers are shown in Table 4.

Example  11

The bicomponent composite fiber of Example 11 was prepared according to the method described below. Using a screw extruder, a PBT-type TPEE (first component) having an intrinsic viscosity of 1.8 dl / g was melted at a melting temperature of 250 ° C and PET (second component) having an intrinsic viscosity of 0.45 dl / g Melting at a melting temperature of 280 DEG C and then releasing them individually quantitatively. The first component and the second component were mixed in a weight ratio of 50:50 and then placed in a spinning cabinet at a spinning temperature of 285 ° C and subsequently extruded through the composite and parallel spinnerette assembly and cooled with cooling air, Twisted air textured yarn (ATY) was prepared by winding at a speed of 3000 m / min, followed by an air-twist texturing process at a processing speed of 500 m / min and a draw ratio of 1.8. The results of the fabricated fibers are shown in Table 4.

The first component
Intrinsic viscosity
(dl / g) The second component
Intrinsic viscosity
(dl / g) Fiber strength
(g / d) Fiber elongation
(E%) Crimp index
(CI) Example 9 1.8 0.45 4.0 25.9 72 Example 10 1.8 0.45 3.6 25.0 60 Example 11 1.8 0.45 3.8 25.4 70

Example  12

The bicomponent composite fiber of Example 12 was prepared according to the preparation method described in Example 2 except that the first component was replaced with a PET-type TPEE having an intrinsic viscosity of 1.1 dl / g. The results of the fabricated fibers are shown in Table 5.

Example  13

The bicomponent composite fiber of Example 13 was prepared according to the preparation method described in Example 2 except that the first component was replaced with a PET-type TPEE having an intrinsic viscosity of 1.5 dl / g. The results of the fabricated fibers are shown in Table 5.

Example  14

The bicomponent composite fiber of Example 14 was prepared according to the preparation method described in Example 2 except that the first component was replaced with a PET-type TPEE having an intrinsic viscosity of 1.8 dl / g. The results of the fabricated fibers are shown in Table 5.

The first component
Intrinsic viscosity
(dl / g) The second component
Intrinsic viscosity
(dl / g) Fiber strength
(g / d) Fiber elongation
(E%) Crimp index
(CI) Example 2 1.8 0.45 4.3 35.1 80 Example 12 1.1 0.45 3.8 31.8 38 Example 13 1.5 0.45 4.2 31.1 47 Example 14 1.8 0.45 4.4 30.3 55

Example  15

The procedure of Example 2 was followed except that the first component was replaced with a PBT-type TPEE having an intrinsic viscosity of 1.8 dl / g and melted at a melting temperature of 250 ° C and a PBT-type having an intrinsic viscosity of 1.2 dl / g TPEE (second component) was melted at a melting temperature of 250 占 폚. The fabricated fibers are shown in Table 6.

Example  16

The first component was replaced with a PET-type TPEE having an intrinsic viscosity of 1.8 dl / g, melted at a melting temperature of 270 ° C and a PBT-type having an intrinsic viscosity of 1.2 dl / g, TPEE (second component) was melted at a melting temperature of 250 占 폚. The fabricated fibers are shown in Table 6.

Example  17

The first component was replaced with a PBT-type TPEE having an intrinsic viscosity of 1.8 dl / g, melted at a melting temperature of 250 DEG C and a PET-type having an intrinsic viscosity of 1.2 dl / g, TPEE (second component) was melted at a melting temperature of 260 占 폚. The fabricated fibers are shown in Table 6.

The first component
Intrinsic viscosity
(dl / g) The second component
Intrinsic viscosity
(dl / g) Fiber strength
(g / d) Fiber elongation
(E%) Crimp index
(CI) Example 15 1.8 1.2 3.7 35.1 70 Example 16 1.8 1.2 3.8 31.8 55 Example 17 1.8 1.2 3.7 33.0 65

Claims (13)

(A) a thermoplastic polyester elastomer (TPEE) as a first component, and
(B) a polyester polymer as the second component
/ RTI > conjugate fiber. The method according to claim 1,
Wherein the thermoplastic polyester elastomer is a thermoplastic elastomer of the polybutylene terephthalate (PBT) type. The method according to claim 1,
Wherein the thermoplastic polyester elastomer is a thermoplastic elastomer of the poly (ethylene terephthalate) (PET) type. 4. The method according to any one of claims 1 to 3,
Wherein the thermoplastic polyester elastomer has an intrinsic viscosity in the range of 0.5 dl / g to 2.4 dl / g. 4. The method according to any one of claims 1 to 3,
Wherein the polyester polymer is selected from the group consisting of polyethylene terephthalate, polyethylene isoterephthalate, copolymers of polyethylene terephthalate / polyethylene isoterephthalate, polybutylene terephthalate, cationic dyeable polyesters, polybutylene succinates, Selected from the group consisting of polyester, biomass polyester, and thermoplastic polyester elastomer recycled to the polymer backbone. 4. The method according to any one of claims 1 to 3,
Wherein said polyester polymer has an intrinsic viscosity in the range of 0.45 to 1.2. 4. The method according to any one of claims 1 to 3,
Wherein the weight ratio of the first component to the second component is in the range of 20:80 to 80:20. 4. The method according to any one of claims 1 to 3,
Wherein the fibers have a side-by-side cross section. 4. The method according to any one of claims 1 to 3,
Wherein the fiber is a fiber of stretched texture yarn (DTY), air texture yarn (ATY), highly oriented yarn (HOY) or fully drawn yarn (FDY). 4. The method according to any one of claims 1 to 3,
Wherein the fibers are long filaments or short filaments. A complex yarn comprising only the fibers according to any one of claims 1 to 10 or formed by complexing the two-component conjugate fibers with other fibers. 10. Fabrics made from the bicomponent composite fibers according to any one of the preceding claims. A fabric produced by the composite yarn according to claim 11.