JP2002509995A - Drawing of polyester filament - Google Patents

Abstract

(57) Abstract Co-drawing of mixed polyester filaments is improved by using chain-branched polyester for the polymer from which the polyester filaments are spun.

Description

DETAILED DESCRIPTION OF THE INVENTION

TECHNICAL FIELD The present invention relates to improved drawing of polyester filaments, and more particularly, to a method of drawing mixed polyester filaments in the same bundle, especially tow of such mixed filaments. And the resulting drawn filaments and bundles, and downstream processes therefor,
And its products.

BACKGROUND OF THE INVENTION Polyester is commercially produced on a large scale, primarily from poly (ethylene terephthalate), for processing into shaped articles such as fibers. Synthetic polyester yarns are known and have been used commercially for decades. It is W. H. First proposed by Carothers in U.S. Pat. No. 2,071,251, then Winfield and Dickson in U.S. Pat.
No. 4,465,319 proposed poly (ethylene terephthalate).

[0003] Although many (including copolymer) polyester polymers have been proposed, the polyester most widely manufactured and used so far for textile fibers is poly (ethylene terephthalate), which is referred to as the homopolymer PET. Is often done. Homopolymer PET is generally preferred over copolymers because it is less costly than copolymers and because its properties are completely suitable or more preferred for most end uses. However, homopolymer PET requires, for example, special dyeing conditions (high temperatures requiring overpressure) that are not required for nylon fibers, and thus copolyesters have been proposed and for some purposes It is known to be used commercially.
Homopolymer PET is often referred to as 2G-T, while poly (
Trimethylene terephthalate) is called 3G-T (some people call this PTT)
And poly (tetramethylene terephthalate) is 4G-
And so on. Although some interest has been shown in 3G-T, and also in 4G-T, 2G-T is by far the most used, and thus is a polyester polymer discussed primarily below, but the present invention relates to other polyesters, for example, will be understood to be applied other C ₂ -C ₄ alkylene terephthalate such as those described above 3G-T and 4G-T, and also copolyesters are expected.

[0004] Polyester fibers are either (1) continuous filaments, or (2) fibers that are discontinuous, the latter often being referred to as staple fibers or cut fibers, which are first extruded into continuous fibers. Manufactured by forming polyester filaments, and the filaments are processed in the form of continuous polyester filament tows before being converted to staples. An important step in the processing of such continuous polyester filaments is "stretching" to increase the orientation of long chain polyester molecules, thereby improving the properties of the filament. The present invention relates to improvements in this stretching step and the improved products obtained therefrom.

[0005] Primarily, the challenge for synthetic fiber manufacturers is to replicate the advantageous properties of natural fibers, the most common of which are cotton and wool fibers.

[0006] Most polyester cut fibers are of circular cross section and are compounded with cotton. However, recently, US Pat. No. 5,591,523 (DP-
6255) and 5,626,961 (DP-6365-A), and 1
Co-pending application no. 08 / filed on June 12, 996 and now permitted
No. 662, 804 (DP-6400) and the corresponding International Publication No. W
O97 / 02372, WO97 / 02373, and WO97 / 02374
Discloses an invention relating to conversion to sliver in a worsted or woolen system, and finally to a polyester tow suitable for downstream processes in such systems for fabrics and garments. The disclosures of which are hereby incorporated by reference. The present invention will be described in the course of its operation, with particular reference to its value in drawing the polyester filaments in the tow for further processing in such a system. It is believed that the potential is not limited to drawing and is more widely used when drawing other bundles of polyester filaments.

For example, as disclosed in US Pat. No. 5,591,523 (DP-6255), it is sometimes desirable to have filaments with different deniers (dpf) from filament to filament, and as such, Unexpected in Example 1 of the present invention, undrawn polyester filaments can be spun, and the undrawn polyester filaments of significantly different denier are spun on the same spinning machine without adjusting the specific draw ratio, A homogenous mixture of these spun filaments could then be simultaneously drawn at the same draw ratio in the same tow to provide filaments with different superior properties due to their different dpf (Column 6, 15).
~ Line 29). The present invention elaborates on this surprising finding and extends it to the simultaneous drawing of a bundle of other mixed filaments beyond the tow of the mixed filaments specified in that patent.

According to one aspect of the present invention, there is provided a method of drawing a mixture of polyester filaments in the same bundle of polyester filaments, the mixture having different cross sections and / or different filaments. A mixture of denier, and the polyester is characterized by being branched having about 0.1 to about 0.8 mole% of chain branching; Is routinely calculated by dividing the molecular weight of the polymer by the molecular weight of the repeating unit of the polymer and multiplying by 100. As a specific example, the repeating unit for 2G-T is ethylene terephthalate.

In accordance with another aspect of the present invention, there is provided a mixture of polyester filaments, wherein the mixture is a mixture of different deniers of different cross-sections and / or from filament to filament, and wherein the polyester comprises about 0.1 From about 0.8 mol% to about 0.8 mol%, and shrinkage is characterized by about 0.5 to about 3%. Such a mixture may be in the form of a continuous product of drawn tow and drawn yarn of continuous filaments, as well as a downstream product of a mixture of polyester filaments obtained therefrom, as well as the yarn, as well as the fabric itself, And a mixture of staple (cut) fibers in various forms, including garments and garments, and the resulting mixture of polyester fibers may be other fibers, such as other synthetic polymers including polyamides (various types of nylons) and polyolefins. It is understood that the fibers may be mixed with natural fibers such as cotton and wool.

[0010] Although the terms "filament" and "fiber" are used generically herein and are not generally intended to be mutually exclusive, these general terms are referred to as " It is sometimes modified as a term such as "continuous filament" and "staple fiber".

As explained in relation to the stress-strain curve in the present example, when the film is simultaneously stretched according to the present invention, the specific stretching ratio has not been found remarkably. Neck drawing has not been found, contrary to our experience, when drawing filaments of homopolymer 2G-T.

DETAILED DESCRIPTION It is redundant to repeat what is already disclosed in the art. As shown, preparation of polyester polymers and spinning of filaments from the polymers has been disclosed in the art. The drawing of polyester filaments is also described by Marshall and Thompson in Nature, Vol.
171 ( Jan. 3, 1953), pp. 38-39, in " Drawing Synthetic Fibers ", J. Am . Applied Chem. , 4 (195
Apr. 4), pp. 145-153, in " The Drawing of Terry line ", and in Proc. Roy. Soc. (London), Vol. A2
21, pages 541-557, " The Cold Drawing of High Polymers ". As mentioned above, the present invention was made during the operation of drawing polyester filaments in tow which had been developed for worsted and woolen processing, and many of the detailed descriptions herein have been made in accordance with that description. Although related to such filaments and tows, the concepts of the present invention have broader applicability.

As indicated, the essence of the present invention is to use a chain-branched polyester polymer to produce a polyester filament drawn by the method of the present invention to provide a mixture of filaments according to the present invention. . Use of chain branching (ie, a polyfunctional polyester-forming intermediate having more than the two essential functional groups required for polymerization, eg, glycols and dibasic acids, both difunctional) U.S. Pat. Nos. 4,092,299 and 4,113,704 to MacLean et al., U.S. Pat. No. 3,335,211 to Mead et al.
Oxford et al., International Publication No. WO 92 / 13,120, Duncan's US SIR H1275, DuPont (Broaddus et al.) European Patent Publication EP.
A2 294,912, Reese U.S. Pat. Nos. 4,833,032, 4,966,740, and 5,034,174; Goodley et al., U.S. Pat. No. 4,945,151. And Varginay U.S. Pat.
No. 76,773, and are disclosed in the prior art, such as the prior art referenced and cited in that specification. Some of these references used different terminology, such as viscosity enhancers, for added materials to enhance spinning performance, or for other reasons. Much of this prior art relates to high speed spinning of continuous filament yarns as feed yarns for draw-texturing, so that the continuous filaments are more suitable for drawing in tow form for conversion to cut fibers. Spin-oriented, rather than amorphous, as appropriate, and cut fibers are particularly interesting and preferred by the present invention. The low shrinkage of the mixture of filaments according to the invention was produced by producing a spun-oriented filament that was spun at high speed and often referred to as POY, for use as a feed yarn for drawing false twist. Distinguish our drawn filaments from higher shrinking filaments.
The shrinkage is the boil-off shrinkage referred to in Knox, U.S. Pat. No. 4,156,071, column 6, bottom line, and is measured by Knox in the manner described there.

As indicated, US Pat. No. 5,591,523 and International Publication No. WO9
7/02372 already discloses in Example I the tow co-drawing of polyester filaments of mixed dpf, and surprisingly this is satisfactory and provides drawn filaments without strong dyeing defects. Has already been disclosed. Such a method and the resulting mixture d
A drawn filament of pf, all of which is an oval cross section decorated with scallops,
It is already disclosed in that specification. In addition, U.S. Patent No. 5,629,961 and International Publication No. WO 97/02373 disclose a filament with an oval cross section decorated with an improved scalloped with six grooves, and International Publication No.
No. 5,591,523, which is part of the disclosure of U.S. Pat. No. 5,591,523, as well as O97 / 02374 and granted U.S. patent application Ser. No. 08 / 662,804. This application is
It is particularly relevant to further aspects of the inventive idea not included in these prior patents and patent applications. Such further embodiments are mentioned here; that is, one cross-section is circular, while the other cross-section is non-circular, such as trilobal, ribbon-shaped, or evenly scalloped oval. A mixture of filaments of different cross-section, not entirely scalloped filaments of oval cross-section; a mixture of more than one non-circular different cross-section, such as a mixture of any such non-circular cross-section A mixture of solid filaments and filaments having one or more longitudinal voids, wherein one void is referred to as a hollow filament and is described, for example, in US Patent Nos. 3,745,061; 3,772,
137, and 5,104,725, and porous filaments having, for example, 3 or 4 voids or having 7 voids, as disclosed in the references referenced and cited therein. Such filaments having longitudinal voids, as far as the terminology herein is concerned, are prepared from the pre-behavior during stretching (made from 2G-T homopolymers without chain branching). Is circular (solid) (also produced without chain branching)
It is technically included in the concept of "non-circular" filaments because it differs from the behavior of the filaments; even with identical cross-sections (other than the elliptical cross-section all decorated with scallops as described above), different dpfs A mixture of filaments of different cross-sections as well as a mixture of filaments of different dpf; such a difference in dpf is that the higher dpf may be at least 1.1 × the lower dpf, or at least Larger differences, such as 1.2 ×, 1.3 ×, 1.5 ×, or more, may be used.

As can be seen in the following examples, it is difficult to predict the dpf and properties of drawn filaments obtained by drawing a mixture of filaments according to the present invention.

The present invention is further described in the following Examples, which for convenience refer to machining in the Worsted system described above. All parts and percentages are by weight unless otherwise indicated. The boil-off shrinkage of the product for all examples ranged from 1% to 1.5%.

Most test procedures are well known and / or described in the art. For the avoidance of doubt, a description of the procedure used is given in the next paragraph.

The Instron mean stress-strain curve was obtained as an average of ten individual filaments of each type taken from the tow bundle as follows. Ten samples of each type of filament were taken from a tow bundle through a magnifying glass (LUXO Illuminated).
Separation using a Magnifier). The denier (DPF) for each filament of each sample filament was measured using a vibrometer (HP Model 201C Audio).
o Oscillator). The sample filaments were mounted one at a time on an Instron (Model 1122 or 1123) and their stress-strain behavior was measured. 10 breaks were recorded for each filament type, and an average of 10 samples was recorded for each filament type, and thus read from the stress-strain curves of the individual filaments, as is easily understood. The values do not necessarily correlate with the tensile properties calculated and listed as an average in the table.

Units- Measurements were made using conventional US textile fiber units containing denier, which is in units of meters. To match other practices recognized by longstanding practices, D
The dtex and CPcm equivalents of the PF and CPI measurements are shown in parentheses after the actual measurements. However, for tensile measurements (MOD for initial modulus, and TEN for tenacity), the actual measurement in gpd was converted to g / dtex, and these latter are shown in the table, The stress-strain curve shows the original metric tensile test value on the Y-axis.

The degree of crimp was measured as the number of crimps per inch (CPI) after crimping of the tow. The crimp is represented by many peaks and valleys in the fiber. Ten filaments were randomly removed from the tow bundle and placed loosely (one at a time) in the clamp of the fiber length measurement device. The clamp is manually operated, and while it is still in the clamp, it is first moved to close together sufficiently to prevent drawing of the fibers. One end of the fiber is placed in the clamp on the left side of the measuring device and the other end is placed in the right clamp. Rotate the left clamp to remove any twist in the fiber. Move the right clamp support slowly and gently to the right (while stretching the fiber) until all of the slack has been removed from the fiber without removing any crimps. Using a lighted magnifier, count the number of piles on the front and back of the fiber. The right clamp support is then slowly and gently moved to the right until all crimps have just disappeared. Take care not to stretch the fiber. Record this length of fiber. The degree of crimp for each filament is calculated as follows: Total number of piles ―――――――――――――――― 2 × filament (uncrimped) length All 10 fibers The average of 10 measurements is recorded against CPI (crimps per inch) and the meter equivalent is CPcm.

CTU (crimp take-up) is also measured on the tow, and the length of the tow stretched to remove the crimp as described in Anderson et al., US Pat. No. 5,219,582. Was divided by the unstretched length (ie, as it was crimped) and expressed as a percentage.

Values for non-circular fiber cross sections were obtained using the following procedure. “Fiber Mic
roscopy Its Technique and Applicatio
ns "in JL Sloves (van Nostrand Co., I
nc. , New York 1958 No. 180-182), the fiber specimens were prepared using a Hardy microtome (Hardy).
US Department of Agriculture irca 378, 1933) and sectioned. The slices were then transferred to the Super FIBERQUANT video microscope system stage (V
ashaw Scientific Co. , 3597 Parkway La
ne, Suite 100, Norcross, Georgia 30092)
And display at the magnification required for the Super FIBERQUANT CRT. Images of individual flakes of one fiber are selected and the critical fiber size is measured. The ratio is then calculated. This process is repeated for each filament in that field to create a statistically significant set of samples, the average of which is shown here. The aspect ratios or deformation ratios for non-circular cross-sections are shown in brackets after the indication of cross-section type in the table. For example, “SO (1.37)” indicates an oval cross section decorated with scallops having an aspect ratio of 1.37. Similarly, the void content is shown in parentheses after the indication of the hollow section. For example, a void content of 7% is designated as "hollow (7%)" and is measured as described by Aneja et al. In US Pat. No. 5,532,060.

The relative viscosity (LRV) of HFIP containing 100 ppm of 98% reagent sulfuric acid
This is the viscosity of the polymer dissolved in the solvent (hexafluoro-isopropanol).
Viscometers are available from a number of commercial vendors (Design Scientific).
Capillary viscometer available from Co., Cannon, et al. The relative viscosity of centistoke is 4.75 wt.% Of the polymer in the solvent. % Solution at 25 ° C. The H ₂ SO ₄ used to measure LRV breaks the crosslinks, especially silicon in the case of tetraethyl orthosilicate branching.

Non-acid relative viscosity (NRV) is the viscosity of a polymer that was similarly dissolved, measured, and compared in a hexafluoro-isopropanol solvent but without sulfuric acid. Since the acid is not present, the crosslinks remain intact when the NRV is measured.

Delta RV (ΔRV) is an expression used herein to identify the difference between NRV and LRV measured as described above, and the acid used when measuring LRV Represents the amount of cross-links broken by

Product defects are divided into three categories in this specification: 1) Equivalent Fabric Defects (EFD) 2) Dark Dye Defects (DDD) 3) Fragments (SPL)

The first two defects (EFD and DDD) are fibers and fiber clumps that dye more heavily than regular fibers. DDD has a diameter of less than four times the normal (drawn) fiber diameter. EFDs have a diameter that is at least four times the normal fiber diameter. Both defects must be longer than 0.25 inches (6.35 mm). The sample is processed on a roller top type card machine. The sliver is stained in light blue and is visually observed under a lighted magnifier. Fibers that stain more intensely than the bulk of the sample are removed and classified as EFD or DDD,
And counted. Each type of defect is reported as the number of defects per 0.1 pound (0.045 Kg) sliver. Debris is too large a fiber or a mass of fibers. To be classified as debris, this defect is also 0.25 inches (6.35 mm)
Must be longer, but their total diameter is 0.0025 inches (0.063
5 mm). The debris is generated when the staple sample is processed on a flat card, with a flat strip lint.
gather). The flat strip lint is visually observed against a black background. Debris is removed, sorted by size, counted, and expressed based on the weight of the sample.

Example 1 Mixed filaments were melt spun at 282 ° C. from a chain branched ethylene terephthalate polymer. Such mixed filaments were a mixture of light filaments (smaller denier) with an oval (SO) cross section decorated with scallops and heavy filaments (heavier denier) with a circular cross section. U.S. Pat. No. 3,397,972 to 0.24% (0.22 mol%) tetraethyl silicate (TES, essentially Mead et al.) Through different capillaries in the same spinneret, each containing 1000 capillaries.
335,211) and 10.2 LRV
And simultaneously melt spinning different filaments at a total speed of 23.68 lbs / hr (10.75 Kg / hr) for each spinneret from a polymer having 15.3 NRV (and thus 5.1 ΔRV) and 1800 yards / min. (1650m /
Minutes) wound on a bobbin. The spinneret has 516 circular tubules, each flow area being 0.0003079 square inches (0.199 mm ² ) to make heavy filaments (circular cross section), and light filaments (elliptical cross section decorated with scallops) ) To make each flow area 0.0002224 square inches (0.1
It had 484 non-circular capillaries, 43 mm ² ). The smaller non-circular tubules were placed on the inner five rings (out of nine), while the larger circular tubules were placed on the outer four rings of the spinneret. The orifice shape for a scalloped oval tubule is described in US patent application Ser. No. 08 / 662,804, referenced above (DP).
-6400) and International Publication No. WO 97/02374. The molten filament stream was cooled using radially directed air from a profiled quench system, as described in Anderson et al., US Pat. No. 5,219,582. The resulting bundle of spun filaments
Different cross-sections and consisted of a mixture of lower and higher denier filaments with the properties shown in Table 1A. A single filament stress-strain curve of two different types of filaments is shown in FIG. The continuous curve is for the lower denier (light) filament of the oval (SO) cross section decorated with scalloped, and the discontinuous curve is for the higher denier (heavy) circular filament. .

[0029]

[Table 1]

Combining the 68 bobbins of the as-spun mixed filaments,
Oval shaped lower dpf filaments decorated with scallops of 60%
Formed a tow of nominal blending ratio with the higher circular dpf filament. This tow was stretched at a stretch ratio of 2.22 times while spraying water at 95 ° C. The tow was then passed through a stuffer box crimper and subsequently loosened at 145 ° C.
B. Both types of crimped filaments of filaments of the properties listed in B
10.6 CPI, 4.2 CPcm) yielded a final tow size of approximately 74,800 denier (83,100 dtex) of the homogeneous formulation.

[0031]

[Table 2]

A conventional finish was applied to provide a finish level of 0.15% (on fiber). The nominal denier per filament (ie, the denier of the total tow bundle divided by the number of filaments) is 1.1 dpf (1.3 dtex), and about 40% of the filaments have a scalloped oval shape (0.98 Denier) and the remaining 60% had a circular shape (1.19 denier).

The product was processed and then inspected for product defects, EFD, DDD and SPL. It is clear that all of them were registered as zero-defects and therefore their product quality was not adversely affected by simultaneous drawing of different shapes and denier mixtures of as-spun filaments, which is surprising. Yes, and contrary to previous experience in attempting to process mixed shape and mixed denier filaments made substantially similarly from homopolymers without chain branching, which would be relevant here.

COMPARATIVE EXAMPLE In contrast, if four mixtures of different filaments of the homopolymer 2G-T without any chain branching were similarly drawn in the same bundle, a table was obtained when the drawn bundle was processed and inspected. A noticeable product defect as shown in C2 was noticed. Table C for stretch ratio
2 as “DR”. Each mixture stretched together has 4 types CA, CB, C
It was a mixture of two filaments from C and CD. Table C shows their characteristics.
It is shown in FIG. Homopolymer 2GT (LRV20.4 without any chain branching)
) Were spun separately, but otherwise substantially as described in Example 1.

[0035]

[Table 3]

[0036]

[Table 4]

Contrary to the zero product defect obtained from Example 1 according to the invention and from the other examples, drawing such a homopolymer blended filament results in a considerable number of product defects. (CA / CB is a mixture of filaments of different deniers, but both are oval cross-sections decorated with scallops with a variant ratio of 1.7,
And CC / CD is a mixture of filaments of the same denier, but one is circular and the other is an oval cross section decorated with scallops with a variant ratio of 1.7). The stress-strain curves for single filaments of these four homopolymers, CA, CB, CC and CD, are shown in FIG. This may then be contrasted with the curves in FIGS. 2 and 4-6 for filaments of chain branched polymers. All of the curves in FIG. 3 have a substantial flat portion that indicates the intrinsic draw ratio for these homopolymer filaments, as is well known. Table C shows their specific draw ratios.
1 as "NDR". As can be seen, the specific draw ratios for CC and CD are both 1.9 ×, ie, both are the same, but CC and C
Co-stretching of the mixture with D resulted in a considerable number of deep staining defects. The curves in FIG. 2 do not show the corresponding flat portions; this is in view of the past events, in most cases of mixed denier and / or co-drawing of the cross-section (where the filament is a homopolymer) It can explain why such filaments can be drawn together and provide a product free of product defects, in contrast to previous experience which is not satisfactory.

Example 2 A mixture of three filaments of different cross-sections, but all 7.6 dpf (8.4 dtex), was treated with 8.9 LRV and 1 containing 0.27% TES.
From 5.4 NRV (6.5 ΔRV) polymer, 1600 yards / min (1460 yards / minute)
m / min), each type being prepared separately by spinning at 282 ° C., substantially as described in Example 1, to obtain as-spun filaments having the properties shown in Table 2A. Offered. 85.2 pounds / hour of the circular filament (
(38.7 Kg / hr) and extruded from a 520 capillary spinneret. The hollow filaments are urged at a rate of 80.4 pounds / hour (36.5 Kg / hour) using an orifice configuration substantially as described in FIG. 5B of US Pat. No. 5,356,582 for 490 hours. Extruded from the spinneret. The scalloped decorated oval filament was extruded at a rate of 73.8 pounds / hour (33.5 Kg / hour) from a 450 capillary spinneret. The stress-strain curve for a single filament of each type is shown in FIG. 4 along with curve 3C, which is the stress-strain curve for the 6-grooved filament described in Example 3 below.

[0039]

[Table 5]

Combining eleven bobbins of circular filament, eleven bobbins of hollow filament, and twelve bobbins of elliptical filaments decorated with scallops, 34% circular, 33% hollow, and 33% Formed a tow of nominal blending ratio of the oval shaped filaments decorated with scallops, and the total denier of the spun tow was 125,476 (139,418 dtex). The tow is stretched, crimped, and relaxed substantially as described in Example 1 except that the stretch ratio was 3.0x to a nominal dpf of about 2.85 (3.2 dtex). These three different types of crimped filaments (8.4 CPI, 3.3 CPcm, 16.
7CTU) of a homogeneous formulation containing approximately 47,000 denier (52,000).
dtex). The properties of the filament are listed in Table 2B.

[0041]

[Table 6]

A conventional finish was applied as in Example 1 and the tow was processed and inspected for product defects. In view of previous attempts using conventional filaments, 3
It was surprising that the slivers obtained from this example of homogeneous formulations of different cross-sections did not show any EFD, DDD, and SPL product defects, despite being drawn simultaneously. .

The feel of the fabric to the consumer can be very important for commercial viability. The aesthetics of the fabric can be significantly affected by using a mixture of fibers of different cross sections. However, heretofore, it was not possible to simultaneously draw such a mixture of filaments from a conventional homopolymer.

Example 3 In Tables 3A and 3B, three differently shaped filaments (as spun and prepared and processed substantially as described in Example 2)
The data for filaments in drawn tow of the same dpf) were compiled. However, an elliptical shape 2C decorated with scallops having only four grooves is described in US Pat.
, 626, 961 (DP-6365-A). As described in Example 2, such a 6
The stress-strain curve for the fluted cross-section filament is included in FIG. 4 as curve 3C. The round and hollow as-spun filaments are substantially identical for both Examples 2 and 3.

[0045]

[Table 7]

[0046]

[Table 8]

2.85 stretched tow of nominal dpf (3.2 dtex) (8.3 CPI, 3.3 C
Pcm, 19.9 CTU) and zero product defects (EFD, DDD, S
PL).

Example 4 In Tables 4A and 4B, data was similarly summarized for four differently shaped filaments prepared substantially as described in Example 2. Circular filaments were extruded from a 286 capillary spinneret at a rate of 70.4 pounds / hour (32 Kg / hour); trilobal filaments were extruded at 44 pounds / hour (20 kg).
(Kg / hr) extruded from a 160 capillary spinneret using an orifice shape substantially as described in FIG. XI of US Pat. No. 2,945,739; an ellipse decorated with scallops The shaped (four-groove) filaments are extruded from a 450 capillary spinneret at a rate of 110 pounds / hour (50 kg / hour); and the hollow filaments are extruded at a rate of 89.4 pounds / hour (40.6 kg / hour). And 3
It was extruded from a spinneret of 63 capillaries. The stress-strain curves for a single filament of these different cross sections are shown in FIG.

[0049]

[Table 9]

[0050]

[Table 10]

20 bobbins of circular filament (66,924 denier, 74,360d
tex), 35 bobbins of trilobal filament (64,400 denier, 71,555 dtex), 4 bobbins of scalloped oval filament (20,520 denier, 22,800 dtex), and hollow bobbin 5 bobbins (21,054 denier, 23,393 dtex) combined, nominally 39% circular, 37% trilobal, 12% scalloped oval shape, and 12% hollow filament Blended tows were formed with a total denier of 172,898 (192,108 dtex). The tow is stretched, crimped and loosened substantially as described in Example 2 to a nominal 4.3d
These four different shapes of crimped (8) with pf (4.8 dtex)
. 9 CPI, 3.5 CPcm, 20 CTU) filaments-resulting in a drawn tow of approximately 64,490 denier (71,655 dtex) of a homogeneous formulation containing filaments, round, trilobal, scalloped oval, and hollow. The properties of the filament are listed in Table 4B. The spun dpf was very similar, but the drawn dpf was significantly different. It shows the difficulty of predicting in advance what will happen when the mixed filaments are drawn together.

A conventional finish was applied as in Example 1. The stretched tow was processed and showed zero product defects (EFD, DDD, SPL).

An enlarged photograph of a portion of the mixture of the filaments is shown in FIG.

Example 5 In Table 5, similarly drawn filaments for only two differently shaped drawn filaments from drawn tow prepared substantially as described in Example 4. The characteristics are summarized. However, only two different cross-sections-circular and trilobal-were combined in the same manner with a proportion of circular fiber-51% and trilobal fiber-49%.

[0055]

[Table 11]

The crimp was measured at 8.9 CPI, 3.5 CPcm and 22.5 CTU. Even though the drawn dpf and filament properties are significantly different from those in Table 4B, the tow is processed to produce zero product defects (EFD, DDD, SP
L). This confirms the difficulty of predicting filament behavior during drawing.

Example 6 An oval cross section decorated with scallops of circular, trilobal and two different deniers (the higher dpf is referred to as "SO-H" and the lower dpf is referred to as "SO- L ") is melt spun substantially as described in Example 4 (hollow filaments are not used in this example); SO-L filaments are 75 lb / hr (34 Kg / hr). ) Extruded through a 450-capillary spinneret at a speed of; SO-H and other filaments were as described in Example 4. The spun denier of the circular, trilobal, and SO-H filaments was nearly identical, but the SO-L was 7.9 dpf (8.8 dtex). The properties as spun are shown in Table 6A. The stress / strain curve of a single filament of the elliptical type decorated with both scallops is shown in FIG. The continuous line is for the higher denier SO-H filament and the discontinuity is for the lower denier SO-L filament.

[0058] As in Example 4, 20 bobbins of circular filament, 35 bobbins of trilobal filament and 4 bobbins of SO-H filament were
5 bobbins of SO-L filament (17,775 denier, 19,750d
tex) in combination with 40% round, 38% trilobal, 12% S
A nominal tow ratio of OH and 10% SO-L was added to the total tow denier 169
, 619 (188, 466 dtex). The portion of the tow is stretched, crimped, and loosened substantially as described in Example 2, all at 3.9 dpf.
Contains a round, trilobal, scalloped oval higher dpf that is (4.3 dtex) and an oval lower dpf decorated with 2.6 dpf (2.9 dtex) scalloped. Approximately 57,018 denier (63,353 dtex) stretched tow (8.7 CPI, 3.4 CPcm, 14
. 8 CTU). The properties of the filament are listed at the top of Table 6B. Another portion of the same tow is placed 145 more in front of the stuffer box crimping machine.
Another route was processed using an annealing machine at 145 ° C. and then loosened at 145 ° C. to obtain a filament tow (11.6C) whose properties are listed at the bottom of Table 6B.
PI, 3.0 CPcm, 10.7 CTU).

[0059]

[Table 12]

[0060]

[Table 13]

A conventional finish was applied as in Example 1. Both drawn tows were processed and zero product defects (EFD, DD) despite the filaments having properties significantly different from the drawn filaments in the other examples.
D, SPL).

Example 7 A mixed filament, both of which had an oval cross section decorated with scallops, was spun from a spinneret substantially as described in Example 1. However, using the polymer described in Example 2, the 516 large capillaries (disposed on the four outer rings of the spinneret) have a flow area of 0 to produce heavy dpf SO filaments.
. 0002717 square inches (0.175 mm ² ). Table 7A shows the as-spun properties obtained for the light and heavy dpf filaments obtained.

[0063]

[Table 14]

The 34 bobbins were combined to form a tow with a nominal blend of 40/60 light / heavy filaments. The tow was stretched at a ratio of 2.6 times, but otherwise stretched, crimped and relaxed substantially as described in Example 1 to about 1.85 (2.1
(dtex) resulted in a drawn tow of approximately 56,000 denier (62,000 dtex) of a homogeneous blend containing lower and higher denier filaments with a nominal dpf. The properties of the filament are listed in Table 7B.

[0065]

[Table 15]

A conventional finish was applied as in Example 1. The tow (CPI 9.6, CP
cm 3.8) is collected in a conventional tow box and compounded with wool for conversion to yarn and then sent to a downstream mill for processing into fabrics.
It was processed very satisfactorily and showed zero product defects (EFD, DDD, SPL). Example 7 is similar to Example 1 of US Pat. No. 5,591,523 in that elliptical cross-section filaments decorated with different denier scallops are drawn simultaneously in the same bundle, but the Example 7 differs in that both types of filaments were produced by being spun through different capillaries in the same spinneret.

The absence of any such product defects in the tow bundle of drawn mixed filaments according to the invention means that a comparable mixed filament bundle of polyester homopolymer (2G-T) without any chain branching. It is very different from the experience in stretching.

[Brief description of the drawings]

FIG. 1 is an enlarged photograph of a cross section of a mixed filament according to the present invention, which is described in further detail herein.

FIG. 2 is an average stress-strain curve of a single filament used in a mixture according to the present invention, which is described more specifically herein.

FIG. 3 is an average stress-strain curve of a single filament used in a mixture according to the present invention, and is described more specifically herein.

FIG. 4 is an average stress-strain curve of a single filament used in a mixture according to the present invention, and is described more specifically herein.

FIG. 5 is an average stress-strain curve of a single filament used in a mixture according to the present invention, which is described more specifically herein.

FIG. 6 is an average stress-strain curve of a single filament used in a mixture according to the present invention, and is described more specifically herein.

──────────────────────────────────────────────────続 き Continuation of front page (81) Designated country EP (AT, BE, CH, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE), OA (BF, BJ, CF, CG, CI, CM, GA, GN, ML, MR, NE, SN, TD, TG), AP (GH, GM, KE, LS, MW, SD, SZ, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AL, AM, AU, AZ, BA, BB, BG, BR, BY, CA, CN, CU, CZ, EE, GE, GW, HU, ID, IL, IS, JP, KG, KP, KR, KZ, LC, LK, LR, LT, LV, MD, MG, MK, MN, MX , NO, NZ, PL, RO, RU, SG, SI, SK, SL, TJ, TM, TR, TT, UA, US, UZ, VN, YUF terms (reference) 4L035 AA08 AA09 BB31 BB33 BB40 BB55 BB89 BB91 CC07 DD02 DD03 DD05 DD18 EE02 EE08 EE20 HH10 4L036 MA05 MA20 MA33 MA39 PA03 PA33

Claims (2)

[Claims] 1. A method of drawing a mixture of polyester filaments in the same bundle of polyester filaments, wherein the mixture is a mixture of different cross-sections and / or different deniers per filament, and the polyester comprises: A drawing method characterized by being branched with about 0.1 to about 0.8 mol% chain branching. 2. A mixture of polyester filaments, wherein the mixture is a mixture of deniers of different cross sections and / or different from filament to filament, and wherein the polyester comprises from about 0.1 to about 0.8 mole%. A mixture of polyester filaments, characterized in that the filaments are branched with a chain branching of from about 0.5 to about 3%.