KR100481093B1 - High Self-Crimping Polyester conjugate yarn and process of producing thereof - Google Patents

Abstract

According to the present invention, two kinds of polymers having a significantly intrinsic viscosity difference through a specially designed inclination circular nozzle, that is, a polyethylene terephthalate having an intrinsic viscosity of 0.45 to 0.65 as the first component polymer and a polyintrinsic viscosity of 0.90 to 1.10 as the second component polymer The present invention relates to a polyester-based composite fiber and a method for producing the same, wherein the methylene terephthalate is composite spun so that each component is arranged in a side by side structure in the fiber length direction. According to the present invention, it is possible to obtain a polyester-based latent crimping yarn with significantly improved spinning workability and bactericidal agent, and exhibits spontaneous high crimping properties in the post-processing relaxation heat treatment process, and also due to the inherent properties of polytrimethylene terephthalate fiber. It is possible to produce a knitted fabric having a soft touch, soft deep color, and excellent drape and bulkiness.

Description

Polyester composite fiber with excellent crimping property and its manufacturing method {High Self-Crimping Polyester conjugate yarn and process of producing}

The present invention relates to a polyester-based composite fiber and a method for producing the same by composite spinning in the side-by-side cross-sectional shape in the longitudinal direction of the fiber using two different polymers.

The conventional side-by-side composite fiber composed of two kinds of polymers has latent crimping, and when it is subjected to relaxation heat treatment through the RELAX process, it spontaneously uniforms as in the principle of bimetal with different thermal expansion coefficients. It is well known that a spiral exhibits high elasticity.

Until now, there have been proposed methods for producing a crimped fiber by varying the quenching speed of each part by the single spinning of one polymer alone and a method of complex spinning by selecting two different polymers. . The method of manufacturing the crimped yarn by quenching has a lack of crimping performance compared to the composite spinning method of two kinds of polymers, and the large-scale production facilities have a lot of equipment limitations. Most commonly commercialized.

As a criterion for selecting heterogeneous polymers, first, a method using the same polymer having only an intrinsic viscosity, and second, copolymers having different shrinkage properties as in situ polymers, for example, general Copolymer with polyester and high shrinkage properties The method which makes polyester one component and two components, respectively, is proposed. However, these manufacturing methods have disadvantages in that the physical properties of the copolymer are generally weak, so that the spinning processability is poor, and the crimping performance of the composite fiber is degraded. This is a difficult step.

In addition, filaments made from polymers having two different shrinkage properties, ie filament yarns produced by the methods mentioned in many existing patents, are either low speed (1000 to 1500 m / min) or high speed (2500 m / min After the stretching process using the yarn spun in the above) in the drawing machine with the temperature of the first gourd roller and the heat-setting part as 80 ~ 120 ℃, 180 ℃ ~ 250 ℃ respectively, that is, after 2 steps, dry heat in the post process In addition, the heat shrinkage difference between the two polymers is caused by loose heat treatment due to moist heat, and thus the crimp formation, high crimping and high stretching effect can be expected.

Therefore, the present invention is to provide a side-by-side type polyester composite fiber that can solve all the problems of the prior art as described above as a technical problem.

In order to solve the above problems, the present inventors first designed a special spinneret and a nozzle capable of complex spinning of polymers having different intrinsic viscosities, and in order to maximize the difference in intrinsic viscosity of the polymers, In addition to excellent low temperature dyeability and soft touch expression, polytrimethylene terephthalate, which has a significantly higher intrinsic viscosity value compared to the existing polyethylene terephthalate, is applied to the composite spinning method of polyethylene terephthalate and side by side type to achieve high circular cross section. Latent crimped composite fibers of crimp performance were produced. In other words, in order to solve process defects such as bending and kneeling in the nozzle surface caused by the difference in inherent viscosity of polyethylene terephthalate and polytrimethylene terephthalate, specially developed spinnerets and nozzles developed in-house are used. It is. In addition, the composite fiber was produced by one step called spin draw process instead of the conventional crimping by two steps of spinning and stretching. As a result, the spongy high crimping property was not only expressed in the post-processing relaxation heat treatment process, but also polytrimethylene tere. Due to the inherent properties of phthalate fibers, a soft knit fabric with excellent soft touch, soft and deep color, drape and bulkiness can be produced. In addition, it was possible to manufacture a polyester-based latent crimping yarn with significantly improved spinning workability and bactericidal agent, and as a result, the present invention was completed.

Therefore, according to the present invention, in the method for producing a polyester-based composite fiber of the side-by-side type composed of two kinds of polymers having a large intrinsic viscosity difference,

Yarn cross section obtained by spin-spinning composite spinning through an inclined circular nozzle using a polyethylene terephthalate having an intrinsic viscosity of 0.45 to 0.65 as a first component and a polytrimethylene terephthalate having an intrinsic viscosity of 0.90 to 1.10 as a second component There is provided a method for producing a polyester-based composite fiber having excellent latent crimpability, characterized by satisfying the following two equations (see FIGS. 4 and 5).

Equation 1 0 ≤ (interface = length of the line segment CD ÷ length of the line segment AB) ≤ 0.6

<Equation 2> 1 ≤ (form = length of line segment EF ÷ length of line segment GH) ≤ 1.4

-Line segment AB: long axis length of the interface between high viscosity and low viscosity

-Line Segment CD: Shortened length of interface between high and low viscosity / 2

-Line segment EF: maximum length of the major axis of the yarn cross section

-Line segment GH: maximum length of short axis of yarn cross section

In addition, according to the present invention, in a side by side type polyester composite fiber composed of two kinds of polymers having a large intrinsic viscosity difference, a polyethylene terephthalate polymer as a first component and a polytrimethylene terephthalate as a second component polymer Circular cross-section composite fiber composed of a polyester-based composite fiber having excellent crimping properties, characterized in that the crimping rate is 20% or more, and the yarn cross section satisfies the following two equations (see FIGS. 4 and 5). Is provided.

Equation 1 0 ≤ (interface = length of the line segment CD ÷ length of the line segment AB) ≤ 0.6

<Equation 2> 1 ≤ (form = length of line segment EF ÷ length of line segment GH) ≤ 1.4

-Line segment AB: long axis length of the interface between high viscosity and low viscosity

-Line Segment CD: Shortened length of interface between high and low viscosity / 2

-Line segment EF: maximum length of the major axis of the yarn cross section

-Line segment GH: maximum length of short axis of yarn cross section

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

In the present invention, the polyethylene terephthalate (hereinafter, abbreviated to PET) used for side by side type composite spinning has an intrinsic viscosity of 0.45 to 0.65, and polytrimethylene terephthalate (hereinafter referred to as PTT). .) Is a polymer with an intrinsic viscosity of 0.90 to 1.10 and uses a large difference in intrinsic viscosity between the two components. As a result, when a general circular straight nozzle (see FIG. 3) is used in the spinning pack, a difference in melt viscosity occurs due to the inherent viscosity difference directly under the spinning nozzle during the spinning process, and the yarn is bent toward a higher melt viscosity (bending or kneeling). ), Resulting in poor spinning fairness and impossible mass production. Therefore, the inventors of the present invention have been applied to the spinning pack (3) of the present invention by producing an inclined angle circular nozzle (see Fig. 2) to offset the difference in melt viscosity and to ensure a stable spinning without the bending of yarn thread.

In the case of the inclined angle circular nozzle, a polymer having a high intrinsic viscosity and a low flow rate is opposite to the B side. By providing a path difference, it is possible to achieve stable spinning without bending the discharge polymer. Therefore, it is important to make the difference in melt viscosity between the two polymers more than 1500 poise in spinning using the inclined angle nozzle. The larger the difference in viscosity, the more favorable spinning, but if the difference in melt viscosity becomes too large above 2500 poise, The phenomenon of bending toward the high viscosity polymer is aggravated and radiation is impossible. In addition, if the melt viscosity difference between the two polymers is less than 1500 poise during spinning, the melt viscosity difference is so small that the polymer rapidly bends toward the A plane where the flow rate is high, resulting in poor spinning processability.

     The PET polymer has terephthalic acid and ethylene glycol, and the PTT polymer has terephthalic acid and propane diol as a main component, and means that the third functional ester forming component is not copolymerized. Control of the difference in melt viscosity of the two polymer components by varying the temperature conditions of the extruder (1, 1-1) of each component to change the thermal history of the polymer melt of each component, or the spinning temperature of the high viscosity component and low viscosity component This can be achieved by adjusting. It is desirable to control the spinning temperature within the range of 265 to 290 ° C. in order to maintain the difference in melt viscosity between the two polymers during spinning in the proper region of 1500 to 2500 poise. In addition, the extruder 1 temperature range of PET is preferably 275 ° C to 295 ° C, and the temperature range of the extruder 1-1 of PTT is adjusted to 250 ° C to 270 ° C. The melt passing through each extruder is supplied to one spinning pack 3 while passing through the gear pumps 2 and 2-1, respectively.

The cross-section of the yarn spun by the melt viscosity difference as described above forms a circular cross section as shown in FIGS. 4 and 5, and the interface forms a round shape with a high viscosity side due to the difference in melt viscosity. The shape of is moved within the range satisfying the following equation by the difference in melt viscosity.

<Equation 1> 0 ≤ interface = length of line segment CD ÷ length of line segment AB ≤ 0.6

-Line segment AB: long axis length of the interface between high viscosity and low viscosity

       -Line Segment CD: Shortened length of interface between high and low viscosity / 2

In addition, it is preferable that the ratio of PET in the composite fiber is 30 to 70% of the total weight, and the ratio of the PTT in the composite fiber is preferably 70 to 30% of the total weight. In addition, as the discharge ratio changes, the yarn cross-sectional shape moves within a range satisfying the following equation.

<Equation 2> 1 ≤ form = length of line segment EF ÷ length of line segment GH ≤ 1.4

-Line segment EF: maximum length of the major axis of the yarn cross section

-Line segment GH: maximum length of short axis of yarn cross section

Although not particularly limited, in the present invention, the speed of the winding 6 is preferably 3000 to 5500 m / min, and in spinning the yarn by using a one-stage spin draw process, the speed of the first gourd roller 4 is 2000 m. Per second or more, the speed of the second high speed roller 5 is set to 4000 m / min or more, which is an advantageous direction for improving the spinning workability and crimp performance. If the drawing temperature of the first gourd roller is too low, a problem of abrasion is caused, and if it is too high, the degree of sag is poor and thus acts in a disadvantageous direction to fairness. Therefore, the temperature of the first roller is preferably in the range of 70 ~ 100 ℃. In addition, if the temperature of the second gourd roller is too low, the setting property is poor, and there is a high probability of defects in the manufacture of woven fabrics in post-processing. In addition, if the temperature is too high, the unevenness is unstable, which acts in an unfavorable direction for the spinning process. . Therefore, the temperature of the second roller roller is about 100 ~ 140 ℃

The composite fiber of the present invention preferably has a strength of 2.0 to 3.3 g / denier and an elongation of 20 to 40%. If the strength is less than 2.0g / denier, the strength is lowered, so there are many threads of spinning, poor workability during the manufacture of the knitted fabric, and the tear strength of the knitted fabric decreases, and the strength exceeds 3.3g / denier. In the case of the fabric, the touch becomes poor after fabrication. In the case of elongation, less than 20% is likely to occur during spinning, and in excess of 40%, the uniformity (U%) may be poor due to the unrest in the spinning process.

According to the present invention, a circular cross-section composite fiber composed of a polyethylene terephthalate as a first component and a polytrimethylene terephthalate as a second component, having a crimp ratio of 20% or more, and a yarn cross section satisfying the following two equations A polyester-based composite fiber excellent in latent crimping property, which is characterized by (see FIGS. 4 and 5), is obtained.

Equation 1 0 ≤ (interface = length of the line segment CD ÷ length of the line segment AB) ≤ 0.6

<Equation 2> 1 ≤ (form = length of line segment EF ÷ length of line segment GH) ≤ 1.4

-Line segment AB: long axis length of the interface between high viscosity and low viscosity

-Line Segment CD: Shortened length of interface between high and low viscosity / 2

-Line segment EF: maximum length of the major axis of the yarn cross section

-Line segment GH: maximum length of short axis of yarn cross section

The composite fiber produced in the present invention preferably has a crimp rate of 20% or more measured by the method described below. PET and PET side-by-side composite fibers have a crimp ratio of 20% or more to enable the production of knitted fabrics having desired stretch characteristics. If the crimp ratio is less than 20%, the stretch characteristics during the production of knitted fabrics are not observed. It becomes bad. In addition, in the case of circular latent crimped yarns having a cross section satisfying the above equation, the interface between two kinds of polymers can be increased compared to the release cross-section latent crimped yarns, and per unit length during the post-treatment relaxation heat treatment process. A larger number of crimps become available, thereby improving the stretch of the knitted fabric. In addition, the circular cross-section in the manufacture of knitted fabrics gives a soft and comfortable fit.

By the following Examples and Comparative Examples will be described in detail the present invention. However, the present invention is not limited to the following examples.

[Examples 1 to 6]

An inclined angle circular nozzle was used for the composite spinning of the side-by-side type of PET and PTT that maximized the difference in intrinsic viscosity. As polymer A, PET polymers with intrinsic viscosity 0.460, 0.550, and 0.635 are used as shown in Table 1, and polymer B is used with PTT polymers with 1.00 intrinsic viscosity, respectively, in the range of 270 ° C to 290 ° C, and the discharge ratio is different. The conditions were changed as shown in Table 1 to prepare a composite fiber using a one-step process using an inclined angle circular nozzle. Cooling air at 23 ° C. was supplied at a speed of 0.35 m / sec at 5 to 120 cm directly under the nozzle, and the amount of emulsion deposition was given in the range of 0.5 to 1.1 wt%. The fiber thus prepared was made into a fabric having 100 g / m 2 using both light and weft yarns and then dyed at 120 ° C. The properties of the prepared fabrics were measured and evaluated as follows, and are shown in Table 2.

Polymer A Polymer B Radiation temperature Viscosity Discharge ratio Plane shape fair Example 1 0.635 1.00 290 1700 5: 5 0.20 1.03 Stage 1 Example 2 0.550 1.00 278 2120 5: 5 0.24 1.04 Stage 1 Example 3 0.550 1.00 285 2000 6: 4 0.25 1.06 Stage 1 Example 4 0.550 1.00 288 1960 4: 6 0.52 1.08 Stage 1 Example 5 0.460 1.00 275 2800 5: 5 0.35 1.07 Stage 1 Example 6 0.460 1.00 290 2100 5: 5 0.37 1.08 Stage 1

The properties of the prepared fabrics were measured and evaluated as follows, and are shown in Table 2.

* Intrinsic Viscosity (I. V., Intrinsic Viscosity): After dissolving each polymer sufficiently in 1% concentration in ortho-chloro phenol of 120 ℃, it was measured using a Ubelrod viscometer in a 30 ℃ thermostat.

* Melt Viscosity (M.V., Melt Viscosity): The polymer to be measured was sufficiently dried at 160 ° C using a vacuum dryer, and then measured at a temperature of 280 ° C using a capillary type rheometer (= Capillary Type Rheometer).

* Crimping rate (Tc,%): Take a sample of 3,000 deniers with 50mg / denia tension. When the sample is crimped during the hydrothermal treatment, the fiber strands are treated with hot water (100 ° C) for 20 minutes under a load of 0.5 mg / denia, which is a level at which no entanglement occurs between the fibers. Leave for time and let dry naturally. After a 1 minute elapsed load of 2 mg / denia, the length L1 was measured after a 2 mg / denia + 200 mg / denia load was applied. The crimp rate is calculated by substituting the measured value into the following Equation 3,

<Equation 3> Tc (%) = (L2 L1) / L2 × 100

* 30% elongation recovery rate of fabric (FR ₃₀ ,%): make 3 sheets of 5.5cm × 30cm each in the direction of warp and weft, install the test piece with the width of 5cm in the tensile tester, and give the specimen Make it straight. Elongation at the time of stress-extension in the stress-elongation curve by stretching to 30% elongation at the rate of 100% / min with the low speed elongation measuring method (JIS L 1018-70) (ε) is measured, and the average of each of the warp and weft directions is calculated by Equation 4.

FR ₃₀ , (%) = (30 ε) / 30 × 100

Radiation fairness Strength (g / denia) Elongation (%) Crimp rate FR ₃₀ (%) Example 1 ◎ 3.30 23 42 86 Example 2 ◎ 2.65 29 65 97 Example 3 ◎ 2.49 35 60 93 Example 4 ◎ 2.78 23 68 95 Example 5 × 1.90 35 75 95 Example 6 ◎ 1.63 37 70 97

When the viscosity difference is more than 2500 poise, spinning processability was poor due to the occurrence of kneeling, and the higher the inherent viscosity difference between PET and PTT was, the more highly elastic yarn was possible. Unlike the case of complex spinning using only the difference in viscosity of PET, the spin draw process, which is one step, was able to express the crimping performance as much as the two-step process of the comparative example described below, and to produce a composite fiber with significantly improved crimp performance. Is possible. When the low viscosity 0.46 PET polymer is used, it is difficult to set the spinning conditions, and the strength of the yarn is low so that the tear strength is lowered when weaving it into the fabric through post-processing.

[Comparative Examples 1 to 4]

In order to overcome the difference in inherent viscosity of the different heterogeneous polymers in the extruder and the spinning equipment as shown in FIG. 1, 50% of two types of PET are used as the polymer A, using the inclined angle circular nozzle. As the polymer B, a composite fiber was prepared using two-step and one-step processes, respectively, at a spinning temperature of 280 ° C to 290 ° C using 50% of PET having an intrinsic viscosity of 0.635 or PTT having an intrinsic viscosity of 0.990. Cooling air at 23 ° C. was supplied at a speed of 0.35 m / sec at 5 to 120 cm directly under the nozzle, and the amount of emulsion deposition was given in the range of 0.5 to 1.1 wt%. The fiber thus prepared was made into a fabric having 100 g / m 2 using both light and weft yarns and then dyed at 120 ° C. The properties of the prepared fabrics were measured and evaluated in the same manner as in Example, and are shown in Table 4.

Polymer A Polymer B Radiation temperature Viscosity Discharge ratio Plane shape fair Comparative Example 1 PET0.550 PET0.630 290 1200 5: 5 0.21 1.04 Tier 2 Comparative Example 2 PET0.460 PET0.635 285 1800 5: 5 0.30 1.05 Tier 2 Comparative Example 3 PET0.550 PTT0.99 280 2100 5: 5 0.25 1.02 Tier 2 Comparative Example 4 PET0.460 PET0.635 280 2000 5: 5 0.34 1.03 Stage 1

Radiation fairness Strength (g / denia) Elongation (%) Crimp rate FR ₃₀ (%) Comparative Example 1 △ 3.84 30 18 63.5 Comparative Example 2 ◎ 2.90 30 35 91.4 Comparative Example 3 ◎ 2.55 25 45 85 Comparative Example 4 ◎ 3.01 28 20 74.9

If the viscosity difference is less than 1500 poise, the spinning processability was poor, and the larger the difference in intrinsic viscosity between the two types of polymers was, the more highly elastic yarns could be manufactured. In the case of the one-step spin draw process, the crimping performance was lower than that of the two-step spinning and stretching process.

As described above, according to the present invention, not only the spontaneous high crimping property is excellent in the one step process using the inclined circular nozzle developed by itself, but also the softness of the fabric is produced by the inherent properties of the polytrimethylene terephthalate fiber. A latent crimp yarn with a circular cross section capable of tactile, soft and deep color and drape and bulky properties could be produced. In addition, it is possible to produce a polyester-based latent crimping yarn having excellent spinning workability, especially no curvature phenomenon and significantly improved bactericidal agent.

1 is a schematic diagram of a radiator used in the manufacturing method of the present invention.

2 is a schematic view of a composite spinning pack used in the present invention.

3 is a schematic view of a conventional general round straight nozzle type spinning pack.

4 is a schematic view of the yarn cross section of the polyester-based composite fiber produced by the present invention.

5 is a schematic diagram showing the deformation of the yarn cross-section according to the manufacturing conditions of the composite fiber produced by the present invention.

※ Explanation of code for main part of drawing

1: Extruder 2: Gear Pump

3: spinning pack 4: first gourd roller

5: second gourd roller 6: winder

Claims (8)

In the method for producing a polyester-based composite fiber of the side-by-side type composed of two kinds of polymers having a large intrinsic viscosity difference, Yarn cross section obtained by spin-spinning composite spinning through an inclined circular nozzle using a polyethylene terephthalate having an intrinsic viscosity of 0.45 to 0.65 as a first component and a polytrimethylene terephthalate having an intrinsic viscosity of 0.90 to 1.10 as a second component A method for producing a polyester-based composite fiber having excellent latent crimpability, characterized by satisfying the following two equations (see FIGS. 4 and 5). Equation 1 0 ≤ (interface = length of the line segment CD ÷ length of the line segment AB) ≤ 0.6 <Equation 2> 1 ≤ (form = length of line segment EF ÷ length of line segment GH) ≤ 1.4 -Line segment AB: long axis length of the interface between high viscosity and low viscosity -Line Segment CD: Shortened length of interface between high and low viscosity / 2 -Line segment EF: maximum length of the major axis of the yarn cross section -Line segment GH: maximum length of short axis of yarn cross section The method according to claim 1, wherein the difference in melt viscosity between the two polymers during spinning is 2500 poise or less. The third functional ester of claim 1, wherein the polyethylene terephthalate polymer, which is the first component polymer, is terephthalic acid and ethylene glycol, and the polytrimethylene terephthalate polymer, which is the second component polymer, is a terephthalic acid and propane diol. The forming component is a method for producing a polyester-based composite fiber excellent in latent crimping, characterized by using a polymer which is not copolymerized. The method according to claim 1, wherein the polyethylene terephthalate polymer as the first component polymer is 30 to 70% of the total weight of the polyester composite fiber, and the polytrimethylene terephthalate polymer as the second component polymer is the total weight of the polyester composite fiber. A method for producing a polyester-based composite fiber excellent in latent crimping, characterized in that 70 to 30%. The method of claim 1, wherein the composite spinning uses a one-stage spin draw process, wherein the first roller speed is set to 2000 m / min or more, and the second roller speed is set to 4000 m / min or more. A method for producing a polyester-based composite fiber having excellent latent crimping properties. The method for producing a polyester-based composite fiber having excellent crimpability according to claim 1, wherein the polyester-based composite fiber has a strength of 2.0 to 3.3 g / denia and an elongation of 20 to 40%. The method for producing a polyester-based composite fiber having excellent crimping property according to claim 1, wherein the polyester-based composite fiber has a crimp ratio of 20% or more. A side-by-side polyester-based composite fiber composed of two kinds of polymers having a large intrinsic viscosity difference, wherein the circular cross-section composite fiber composed of a polyethylene terephthalate polymer as the first component and polytrimethylene terephthalate as the second component A polyester-based composite fiber having excellent crimping properties, characterized in that the crimping rate is 20% or more, and the yarn cross section satisfies the following two equations (see FIGS. 4 and 5). Equation 1 0 ≤ (interface = length of the line segment CD ÷ length of the line segment AB) ≤ 0.6 <Equation 2> 1 ≤ (form = length of line segment EF ÷ length of line segment GH) ≤ 1.4 -Line segment AB: long axis length of the interface between high viscosity and low viscosity -Line Segment CD: Shortened length of interface between high and low viscosity / 2 -Line segment EF: maximum length of the major axis of the yarn cross section -Line segment GH: maximum length of short axis of yarn cross section