MXPA97009998A - . new estopas or make filaments in polies - Google Patents

Abstract

The present invention relates to a tow or bundle of filaments which is suitable for processing on a worsted or worsted wool system and consisting essentially of continuous polyester filaments of an average concentration per filament of up to 5 dtex, wherein The filaments have a cross-section that has a notched oval shell shape, and the notches run along the length of the filaments, characterized in that the polyester polymer is of a relative viscosity (LRV) of 8 to 12 and the content of the chain brancher is from 0.3 to 0.7% in m

Description

NEW STOPS OR MADE OF POLYESTER FILAMENTS Field of the Invention The present invention relates to new tow or bundles of filaments which are suitable for the conversion to a twine or wick of a worsted or worsted wool system and to the downstream processing on such systems, and to the processes that are related thereto. and the products obtained from them.

Background of the Invention The polyester fibers are either (1) continuous filaments or (2) fibers that are discontinuous, which are ultimately referred to frequently as staple fibers or cut fibers. Both terms "fiber" and "filament" are frequently used here in an inclusive manner. The use of one term does not exclude the other, unless a qualified term, such as "continuous filament", or "cut fiber" is used. The polyester staple fibers are first made by extrusion into continuous polyester filaments Rei.026014, which are processed in the form of a tow or bundle of continuous polyester filaments before being converted into staple fibers or staples. This invention provides new continuous tow or bundles of filaments that provide advantages because they are capable of being processed better in the downstream direction of the yarn or combed wool system. For the most part, the goal of synthetic fiber producers has been to duplicate the advantageous properties of natural fibers, the most common of which have been cotton and wool fibers. Most of the polyester staple fibers have been of round cross section and have been mixed or combined with cotton. A typical woven or spun yarn is a cotton count of 25, and a cross section containing about 140 fibers per 1.5 dpf (denier per filament) and 3.81 cm (1.5 inches). It has been customary to equal the pfd and the length. The denier is the weight in grams of 9000 meters of fiber and therefore is an effective measure of the thickness of the fiber. When referring to denier, the nominal or average denier is often proposed, since there is inevitably a variation along the extremity and from end to end, that is, along a length of the filament and between the different filaments , respectively. In general, it has been the goal of the fiber producers to achieve as much uniformity as possible in all the processing steps along the end and end to end to produce a polyester fiber of round cross section and a Unique denier and denier as uniform as practical. The 1.5 dpf and 3.81 cm (1.5 inches) in length corresponds to 1.7 dtex and almost 4 cm. The polyester / combed yarn yarns are different from the polyester / cotton yarns, typically having a count of 23, and of cross section containing about 60 fibers of a single yarn and about 42 fibers per yarn of double layer, with the fibers that have been 4.4 dtex and 9 cm in length (4 dpf and 3.5 inches). The count of the yarn can vary above 55 of combed wool or 10 of combed wool, while the denier and the length can vary up to about 4.5 (5 dtex and 11.5 cm) and descends to about 3 (3.3 dtex and 7.5 cm) . It is only relatively recently that the advantages of using the lower pfd synthetic fibers than the corresponding natural fibers (such as wool) have been found to be practical and / or recognized. Recent attempts to provide a low dpf fiber for blending with wool over the combed wool system have not been successful, however, and an improvement is required. When the denier of the fiber has been reduced, the fibers have become harder to process (carving, drawing, combing in the gilí, etc.) in the fabric factory. Indeed, under a certain fiber denier, the polyester fibers that have been tested, have been practically impossible to process, and / or have provided poor quality fabrics. Accordingly, for commercially acceptable processing and blending with wool in practice, it has been found that the fiber denier of such polyester fibers has become a minimum of about 3.3 dtex (3 dpf). Stuffs or bundles of dpf (nominal) filaments less than 3 are not believed to be commercially available at present. This has been the current state of commerce. Therefore, the attempt to manipulate a desire to reduce the pfd seems to have been contradictory or incompatible with the processability in a spinning mill, satisfactory. The processing on the combed wool system is completely different from the most common practice carried out on the cotton system, which generally uses cotton fiber that is sold in bales and that can be mixed with polyester fibers that are mainly cut or cut fibers, which are also sold in packaged bales. In contrast, for processing on their system, operators of combed wool may want to buy a tow or filament bundle of polyester fiber (instead of a compact bundle of staple fiber) so that they can convert the tow or filament bundle (which is continuous) in a continuous twine (a continuous end of discontinuous fibers, referred to herein briefly as "staple fibers") by cutting by crushing or breaking by stretching. This twine is then processed (as a continuous end) through several stages, ie, stretched, dyed, countercurrent treatment, combed on the gilí, stretching on the spindle and, in general, finally the mixture or combination with the money. It is very important, when carrying out the processing on the combed wool system, to maintain the continuity of the twine. Also, however, it is important to be able to treat the fiber cut in the twist appropriately, while maintaining a reasonably satisfactory processing speed for the continuous twist. As indicated, recent attempts to reduce the dpf for tow or polyester filament bundle for the processing of combed wool have not produced the desired results. For example, unsatisfactorily low machine productivity speeds have been required during drying, it is believed that this may be because such polyester fiber has been pre-packaged in a too tight manner. As indicated, the commercially available polyester staple fiber has hitherto generally been of round cross-section. The price of polyester fiber is generally an important consideration, and a round cross section is the cross section easier to make and more economical. Other cross sections have been suggested for various applications, but it is not known that any other cross section (other than round cross section) has actually been processed commercially and used in polyester / combed / commercially available wool clothing, except for specialty applications that may demand a higher price. According to one aspect of the invention, a tow or bundle of filaments is provided which is suitable for processing on a worsted or worsted wool system and consisting essentially of continuous polyester filaments of average concentration up to about 5 dtex per filament , and preferably in the form of about 0.8 to about 5 dtex (0.7 to 4.5 dpf), wherein the filaments have a cross section that is of a shell-oval shape with notches, and the notches run along the length of the edges. filaments. It is believed that the tow or tow of polyester filaments whose filamentary cross-section is shell-shaped / oval with notches running along the filaments, has not been previously sold for processing on the worsted / worsted wool system. Such a polyester tow is usually sold in large tow boxes. It is in the downstream products and their processing that the advantages of the invention are mainly demonstrated, as will be illustrated hereinafter. Such advantages are particularly significant for lower dpf products, preferably in the range of 0.7 to 2.5 dpf (0.8 to about 3 dtex), and especially in the range of 0.8 to 1.5 dpf (0.9 to about 2 dtex), but are also available the improvements for normal dpfs. In addition, the invention is not restricted to any type of polymer or modification and is easy and relatively inexpensive to produce commercially. Such downstream products, in accordance with the invention, have also been provided, especially the polyester fiber (cut) twines of the continuous combed wool system, and the yarns, fabrics, and garments of such twills , including those of blends of polyester fiber and wool fiber and / or, if desired, other fibers, and processes for their preparation and / or their use. According to a preferred aspect of the invention, there is provided a process for preparing a tow of stretched, folded or pleated polyester filaments for conversion to worsted-polyester yarns, wherein such a process comprises the steps of forming filaments of polyester polymer prepared with a chain branching agent, and shell-shaped oval with notches running along the length of the filaments, by spinning through the capillaries, using air off or reducing the temperature directed radially from a system for reducing the profiled temperature, collecting such filaments in bundles or bundles, and combining them into a tow, and subjecting the filaments to stretching or pleating operations in the form of such tow or bundle of filaments. Figure 1 is an amplified photograph of the cut filaments to show a shell-shaped, oval-shaped cross-section, with notches running along the length of the filaments, such as those that can be used in tow or bundles of filaments according to the invention, including downstream products.

Figure 2 is a schematic illustration of a capillary hole for spinning such polyester filaments. Figure 3 plots or graphs the fiber to fiber friction coefficients against the velocity for the shell-shaped cross-section filaments and for the filaments of round cross section, as explained in Example 1.

Detailed description of the invention As indicated, this invention relates to tow or bundles of polyester filaments which are suitable for processing on worsted-worsted wool systems, which are suitable for processing on worsted or worsted wool systems. For reasons of convenience, most of the detailed description hereinafter will be applied to the combed wool system, but, as will be understood by those skilled in the art, the invention is also applicable to the yarn system. Presently, such tow as are commercially available, it is believed that they have been stretched, pleated continuous filaments of a round cross section of the filament and a denier value of about 900,000 (1 million dtex), each filament being about 3.3 dtex ( 3 deniers) or greater. The use of such round cross section filaments was the prior general commercial practice in the production of tow for processing on the combed wool system. The present invention, however, is primarily directed to providing a polyester tow (continuous filaments of stretched polyester, pleated, in a large bundle of filaments and including the twines resulting from staple fibers) for processing on the combed wool system (the requirements for which are already known in the art) with filaments of a different cross section, as indicated. The cross sections of the polyester filaments used according to the invention should not be round but in the shape of a shell-oval with notches running along the filaments. Typical of such cross sections is an oval shell-shaped cross section with 4 notches, such as the one generally described by Gorrafa in U.S. Pat. No. 3,914,488, the description of which is hereby expressly incorporated by reference, and an amplified photograph (1500X) of such filaments is shown in Figure 1 of the attached Drawings. The tows of such filaments are described and illustrated in the Examples given hereinafter. The term "oval" is used herein generically to include elongated shapes that are not round, but have a dimensional ratio (ratio of length to width of the cross section) that is greater than 1, preferably greater than about 1 / 0.7. (corresponding to a length A of the major axis: length B of the minor axis as described by Gorrafa, of 1.4); and preferably less than about 1 / 0.35 (which corresponds to the Gorrafa preference of up to about 2.4), at least as far as the shell-oval shape is concerned. The expression "W / L" is used here, for example in the Tables of the Examples, to indicate the average width / length ratio of the cross sections of the filaments, which is the inverse of the dimensional proportion. The provision of notches (indentations or channels) is also important. This is described in the art, and in co-pending patent applications of the same applicant Nos. 08 / 497,495 (DP-6255) and 08 / 642,650 (DP-6365-A) referred to hereinbefore, the descriptions of which are expressly included hereby for reference, but which express some different preferences therein. The pleating and drawing and most of the other conditions and characteristics of the product and the processing have already been described in the art, for example those referred to it. The polyester polymer used to make the filaments should desirably be in essential form the homopolymer 2G-T (different from the one having the content of the chain brancher, if desired), ie poly (ethylene terephthalate), and should preferably be of relatively low viscosity; LRV polymers of about 8 to about 12 have been found to give very good results as indicated hereinafter in the Examples. The use of air for radially directed temperature reduction from a profiled temperature reduction system, as described by Anderson, et al., In U.S. Pat. No. 5,219,582 is preferred, especially when the spinning of such a low viscosity polymer is carried out. If desired, as indicated, the polymer may be branched chain, for example, as indicated in the Examples. This technology has been described extensively in various techniques, including Mead and Reese, U.S. Pat. No. 3,335,211; Maclean, et al. U.S. Patent Nos. 4,092,299 and 4,113,704; Reese, U.S. Patents No. 4,833,032, EP 294,912, and the technique described therein, by way of example. The amount of the chain brancher will depend on the desired result, but generally 0.3 to 0.7% mol of the polymer will be preferred. Tetraethyl silicate (TES) is preferred as the chain brancher according to the present invention. As described by Mead and Reese, one advantage of using TES is that it is hydrolysed to the latter to provide a product of a low level of pill formation. In addition, polyester copolymers can be used, as shown in Example X, for example. Aesthetic considerations are very important in clothing and other textile applications. The applications of combed wool clothing include, for example, men's and women's suits, loose pieces, pants, wool jackets, military and career uniforms, outerwear and knitted fabrics. As indicated hereinafter and in the previous Background, the tow or bundles of filaments of the invention (including their resulting twists) can be processed with advantage over the combed wool system. A suitable capillary hole shape is shown in Figure 2, and the process preparation steps are also described hereinafter in the Examples; These generally follow normal procedures, except for what is described here.

The invention is further illustrated in the following Examples, which, for reasons of convenience, relate to the processing of the combed wool system, which is generally more important, but the tow or bundles of filaments of the invention could also be processed on a system of yarn. Most test procedures are well known and / or described in the art. To avoid doubts or problems, the following explanation of the procedures that were used in the invention are given in the following paragraphs. The measurements were made using textile units of E.U.A. conventional, including the denier, which is a metric unit. To satisfy the descriptive practices in any place, the dtex and CPcm equivalents of the DPF and CPI measurements are given in parentheses after the actual measurements. For tensile or tensile measurements, however, the actual measurements in gpd have been converted to g / dtex and the latter are those that have been provided. The frequency of pleating or curling was measured as the number of folds or bends per inch (CPI) after the pleating of the tow or bundle of filaments. The fold or fold is exhibited by numerous peaks and valleys in the fiber. Ten filaments are removed from the tow or random tow and placed (one at a time) in a relaxed state in staples or clamps of a fiber length measuring device. Staples or clamps are manually operated and moved initially close enough together to prevent stretching of the fiber while it is placed on the staple or clamp. One end of a fiber is placed on the left clamp or clamp and the other end on the clamp or right clamp of the measuring device. The left clamp or clamp is rotated to remove any kink in the fiber. The support for the clamp or right clamp is removed slowly and gently to the right (extending the fiber) until all the relaxation has been removed from the fiber but without removing any crease or fold. Using an illuminated amplifier, the number of peaks on the top and bottom sides of the fiber are counted. The support of the clamp or right clamp is then moved slowly and gently to the right until all the folds have disappeared. Care must be taken not to stretch the fiber. This length of the fiber is recorded. The frequency of the folds for each filament is calculated as: Total Number of Peaks 2 x Filament Length (Without Folds) The average of the 10 measurements of all the fibers was recorded for the CPI (folds per inch). The CTU (shrinkage of the folds) is measured on a tow or bundle of filaments and is a measure of the length of the tow or bundle of filaments extended, to remove the folds, divided by the length not extended (ie when it is folded or folded), expressed as a percentage, as described in Anderson et al, US Patent No. 5,219,582. The fiber to fiber friction coefficients shown in Figure 3 were obtained using the following procedure. A test cotton sheet weighing 0.75 grams is made by placing fibers on an adhesive tape 2.5 cm (one inch) wide by 20 cm (8 inches) in length. For fiber-to-fiber friction measurements, 1.5 grams of the fibers are attached or fixed to a 5 cm (2 inch) diameter tube that is placed on a rotating tube in the mandrel. One end of the test cotton sheet is fixed to a traction meter and folded onto the mandrel covered with the fiber. A weight of 30 grams is fixed at the opposite end and the tensions are measured when the mandrel rotates at various speeds over a range of 0.0016 - 100 cm / sec. The coefficients of friction are calculated from the stresses that are measured. Other methods for comparing the effects of friction are described in the following Example II which is given here below. The relative viscosity was determined as described by Broaddus et al in U.S. Pat. No. 4,712,988, but using a solution of 80 mg of the polymer in 10 ml of hexafluoroisopropanol solvent a ° C. EXAMPLE I The shell-shaped cross-section filaments (Figure 1) and 8.4 dtex (7.6 dpf) were melt spun at 282 ° C from the poly (ethylene terephthalate) polymer containing 0.40 weight percent of tetraethyl silicate (as described in Mead, et al., US Patent No. 3,335,211) and having a relative viscosity of 10.1. The polymer was extruded at a rate of 33.5 kg / hr (73.8 lbs / hr) from a bead containing 450 capillaries. The shape of the orifice of the capillaries of the row was as shown in Figure 2 and that of the orifice area of 0.2428 cm2. The filaments were spun at an extraction rate of 1460 meters / minute (1600 yards per minute) and turned off or reduced in temperature using radially directed air from a profiled shut-off or reduction system, as described by Anderson, et al., US Patent No. 5,219,582. The spun filaments were wound as a bundle on a coil to give a denier of the total filament bundle of 3420 (3800 dtex). Thirty-seven beams or bales of the coil were combined to form a tow or strand of denier filaments of 126,540 (140,000 dtex) for simultaneous stretching. The tow or bundle of filaments was stretched at a stretch ratio of 3.0X in a water-spraying apparatus at 95 ° C. The tow or bundle of filaments was then passed through a packed box folder and subsequently relaxed to 145 ° C to give a final tow size of approximately 55,000 dtex (50,000 denier) with a nominal (average) pfd approximately 3.0 (3.3 dtex), whose filament properties are listed in Table 1 (the SI equivalents are given in parentheses after the US units that are measured by DPF and CPI as mentioned above, while the measurements of the tension in gpd have been converted to g / dtex in all these Examples).

Table 1 DPF Mod Ten% EB CPI W / L Thread 7.8 18 0.7 287 0.68 woven (8.4) Thread 3.0 47 2.3 17 0.65 Stretch (3.3) (3.2) do A conventional finish was applied to provide a level of finish on the fiber of 0.15% by weight. The tow was collected in a conventional tow box and sent to a yarn factory for downstream processing, combining it with the yarn and converting it into yarn. Successful processing in a tow spinning mill (including cutting to form a continuous twine, dyeing, drawing on a spike, passing through the gill machine, etc.) is critical to commercial feasibility or feasibility. Poor spike results lead to process efficiency losses and / or unacceptable product quality. It is surprising that the processing of the tow and the twine resulting from the present Example (cross-sectional fibers in the shape of a shell-oval) was significantly superior to the processing of the tow that was similar except that it contained fibers of the same denier but in section. transversal cross. In other words, it is surprising that the twists were essentially the same in each aspect except that one according to the invention (because of the shell-shaped fibers), with notches or channels running along the length of the filament) was much superior in the processing characteristics than a twist of fibers of another similar way, of round geometry, and that the first one provided eventually tissues and clothes of superior tactility. The fiber-to-fiber friction coefficients of the two types were measured and compared in Figure 3. It will be noted that round fibers generally have a higher coefficient of friction than cross-sectional, oval-shaped fibers. It is believed that round fibers may have been more difficult to process due to these higher levels of fiber to fiber friction during several spike operations.

EXAMPLE II In Table 2, the data are summarized in a similar manner for the spun fibers essentially as described in Example I and where the polymer performance (performance measured in pounds / h, but given in kg / h) in the capillary, it was varied, by which the denier of the fiber is changed. The coils were combined to form a tow and then stretched at a stretch ratio of 2.6X, but differently than in Example I. The size of the final tow was approximately 50,000 denier. These tows and their twines showed good processing characteristics downstream.

Table 2 COMPARATIVE MEASUREMENTS AGAINST ROUNDPOWER As indicated, when a tow and the resulting twine are processed in a spinning mill, this is critical for commercial viability or feasibility. To estimate the performance of the product in the spinning mill, the friction of the pad of the staple and the cohesion of the twine, both a measure of fiber to fiber friction, were measured on stretched fibers of Article D and the results are compared with the measurements carried out in a similar way on commercial fibers of the same pfd and of an equal CPI value, but of round cross section. The procedures used in the present case were carried out as follows: The friction of the staple pad is measured by the force required to pull a movable sled under a known weight. The force is measured by an Instron model 1122 device. The known weight is 5 cm (2 inches) long, 4 cm (1.5 inches) wide and 4 cm (1.5 inches) wide, weighs 496 + 1.0. g is connected to the top adjustment screw of the Instron device with 38 cm (15 inches) of a nylon cord, while a movable sled, a metal table of 23 x 15 cm (9 x 6 inches) is connected to the adjustment screw lower, so that the sled can only move vertically. The nylon cord at rest is not under tension. The metal table is covered with paper 3M of hardness 240, 3 Mite, RBC, PSA. The weight is covered with wire cloth # 220JM529 from Behr-Manning or equivalent on the side that is facing the table. A sample of the fiber pad (as described in the next paragraph) is placed between the movable sled and the weight. When the Instron device is activated, there is a small relative movement between the staple pad and the sled or weight; essentially all the movement results from the fibers that slide one over the other. This gives a measure of the friction properties of fiber to fiber. Four determinations are made on each of the two samples of the twister pad. The reported value is an average of the eight measurements recorded on the two samples of the twister pad. A tow sample is first carded on a Saco-Lowell roll or cylinder type card and a 10 cm x 6.3 cm (4 inches x 2.5 inches) size pad and a weight of 1.5 + 0.15 g is prepared. The thickness of the pad can be increased by stacking layers of the twine until the proper weight is obtained. The sample is placed on the front end of the movable sled and the weight of 496 g is placed on top of the sample. The distance between the sled and the upper adjustment screw is adjusted to 20 cm (8 inches) and calibrated to 0.5 kg for full scale loading. The speed of the crosshead or head is adjusted to 32 cm (12.5 inches) / min. The crosshead or head travels 4 cm (1.5 inches) before stopping the test when the crosshead or head is stopped.The weight of 496 g is removed from the sample pad and the pad is turned 180 ° keeping the same turned up. The weight is then replaced on the pad and the test is repeated.When the crosshead or head stops, the pad is turned up and down and the test is repeated.When the crosshead or head stops, the pad is rotated 180 ° and the test is repeated.After the fourth observation, a second twist pad of the same fiber is tested.The friction of the fiber pad, SPF is defined as: SPF (%) - Stress x 100 weight (496 g) The average of the eight readings is recorded as the measure of the friction of the fiber pad (fiber to fiber). The results of the fiber pad friction test are given in Table CA for round fibers of 3.3 dtex (3 dpf) and for Article D of Example II, as well as CPI values, which are matched.

Table CA A comparison of these friction values of the fiber pad shows that the fiber of the tow of the invention has a much lower fiber to fiber friction, only about 60% of that of the conventional round fiber [thereof 3.3]. dtex (3 dpf) and of equal value of CPI]. The twine cohesion tests were carried out both before and after the dyeing. The twine cohesion tests consist of the carding to make a twist of 30 cm (12 inches) in length, hanging the twine vertically and adding weights in the lower part until a limit of load support is reached (ie, until the fibers in the twine move apart or separate and the weight (s) fall out.For dry items, the twines were tightly compacted in nylon bags and pressure stained at 121 ° C (250 ° F) for 30 minutes with disperse blue G / F stain, and then dried in an air oven under pressure at 132 ° C (270 ° F) for 30 minutes before the cohesion is measured. the frictional property between the articles before and after the dyeing, again, for comparison, the tests were carried out on twines of the same round fiber of 3.3 dtex (3 dpf) (of the same polyester and equal value of CPI) sold in the form commercially available, the results of the Rope cohesion tests are given in Table CB.

Table CB The twine of the invention (of shell-shaped cross-section) had much lower torsional cohesion values than the twist of the conventional round fiber type (of the same dpf) both before and after dyeing.

EXAMPLE III Table 3 summarizes the data for the fiber yarns, combined into tow or bundle of yarns, and stretched, essentially as described in Example IID, and in Table 2, but where the size of the capillary was varied, as was the number of holes (# in Table 3) in a row and hence that the optimum dpf could be obtained for a given polymer production rate. The tow and its twines showed good processing characteristics downstream.

Table 3 EXAMPLE IV Table 4 summarizes the data in a similar fashion for spun fiber materials stretched essentially as described in Example IIIB, but stretched at different stretch ratios. The resulting tow were processed without showing any defect in dyeing.

Table 4 EXAMPLE V The filament tow is made, stretched and processed in a manner similar to the description in Example I, except that these filaments were spun at removal or extraction rates of 730, 1460 and 1830 meters / minute (corresponding to 800 , 1600, and 2000 yards / minute) and that the polymer was extruded at speeds of 17, 24.6, and 30.8 kg / h (corresponding to 37, 54.2, and 67.8 pounds / hour).

EXAMPLE VI A. The poly (ethylene terephthalate) filaments of 10.2 dtex (9.2 dpf) were spun by fusion as described in Example 1 except that the polymer was extruded at a rate of 41 kg / h (90 pounds / hr) per position on a commercial machine of 44 positions (450 filaments per position), and all of the filaments were collected to form a tow in a container. The denier of this tow was approximately 182,160 (202,400 dtex) and the total number of filaments was 19,800. The properties of the filaments, as they are spun, are indicated in Table 6, Article A. Twelve supply containers of the spun material were combined together to give a tow that is quantified up to 237, 600 filaments and a total denier value of approximately 2.2 million. The tow was stretched at a stretch ratio of 3.0X in the spray-drying at 95 ° C with water. The tow was then passed through a filler box folder and subsequently relaxed at 130 ° C to give a final tow denier of approximately 780,000 3.6 dtex (3.2 dpf) fibers, and a conventional finish was applied to provide a level of finish on the fiber of 0.15% by weight. The tow was collected in a conventional tow box and sent to a spinning mill for downstream processing, combination with wool, and yarn conversion. The properties of the stretched fiber are also shown in Table 6, Article A.

B. The filaments for Article B were prepared and processed in a similar manner except that the polymer was extruded (in the same position / yield) through 711 capillaries per position, ie 711 filaments per position. "#" in Table 6 indicates the number of capillaries (filaments) per position.

Table 6 Properties of Woven Material Properties of Stretched Material It is surprising that the processing of such tow and the resulting twists (of the shell-shaped cross-section fiber) was significantly superior to the processing of the tow which were similar, except that they contained fibers of cross section; it is believed that the latter may have been difficult to process due to the effect of unacceptably high levels of friction during several drawing operations on a spike.

EXAMPLE VII The filaments, of similar shell-shaped cross section, were spun materials of 8.3 and 3.4 dtex (7.5 and 3.1 dpf), but otherwise essentially similar to the procedure described in Example VI at speeds of 33.5 and 32. kg / h (73.8 and 70 lbs / h) per position from a 48-position spinning machine through 450 and 1054 capillaries, respectively, per position. The total denier value of the tow or fabric collected in the cans was, respectively, approximately 162,000 and 379,440. The properties of the material as it was spun, are indicated in Table 7, Articles A and B, respectively. For article A, 14 containers or canisters of the supply of the spun or woven material were combined together to provide a tow with a total denier value of approximately 2.3 million (2.6 million dtex) that were processed (stretched, pleated, and relaxed) essentially as described in Example VI to give a final tow size of approximately 959,000 dtex (863,000 denier). The properties of the stretched material are also listed in Table 7 for Article A and for Article B, which were processed in a similar manner.

Table 7 Each tow was collected from a conventional tow box and sent to a spinning mill for downstream processing, combination with wool, and yarn conversion, which worked satisfactorily. In Article B, the tow was of filaments of very low dpf value, but processed successfully in the spinning mill. This was very surprising because the tow consisting of a round fiber geometry of 2.2 dtex (2 dpf) was not processed acceptably but caused problems of productivity, efficiency, and quality, despite its higher denier value . The tow essentially made as described in Article A of this Example VII was treated with a durable silicone elastomer finish prior to blending with the wool, using an aqueous emulsion at a 0.25% concentration of the amino methyl polysiloxane copolymer in a water bath at room temperature at a rate of 3.6 kg / h (8 lbs / h), and then dried in an oven at 149 ° C (300 ° F) for 5 minutes to cure the silicone. The resulting silicone level on the fiber was 0.3% by weight. The application of this silicone improved the softness and elasticity of the resulting yarns or fabrics, because it reduced friction from fiber to fiber and from yarn to yarn, so that it gave better aesthetic characteristics somewhat similar to previous experience with the application of the silicone glide agent to the fiber filling for use in filled articles. In this regard, reference is also made to the co-pending application of the same applicant No. 08 / (DP-6460) which is filed simultaneously with it.

EXAMPLE VIII A tow of poly (ethylene terephthalate) filaments of 3.7 dtex (3.3 dpf) was prepared by spinning the molten material (from the polymer containing 0.58). % by weight of tetraethyl silicate and having a relative viscosity of 8.9) essentially as described in Article B of Example VII. Woven or spun tow collected in a foil container or can had a total denier value of approximately 166,953 (185,500). Fifteen containers or canisters of yarn supply were combined together for a total denier value of approximately 2.5 million dentex (2.8 million dtex) that was processed (stretched, pleated, and relaxed) essentially as described in Example VI to give a final tow size of approximately 1 million dtex (900,000 denier). The properties are listed in Table 8 for both the filaments as they are spun as for the stretched filaments.

Table 8 Properties of Spinning Material Properties of Stretched Material The tow was collected in a conventional tow box and sent to a spinning mill for downstream processing, including stretch breaking, followed by wool combination, yarn conversion, and weaving, which was done satisfactorily, despite the very low value of dpf.

EXAMPLE IX In Table 9, the data for the spun fibers are summarized essentially as described in Example I, except as indicated, from the polymer described in Example VIII. The tow or bundles of woven yarns were stretched and processed as described in Example II to give tow or bundles of drawn yarns that demonstrated good processing characteristics downstream.

Table 9 Properties of Spinning Material Properties of Stretched Material EXAMPLE X A. The poly (ethylene terephthalate) filaments of 3.3 dtex (3.6 dpf) were spun in the molten state at 293 ° C from the polymer containing 2.1% (by weight) of carbon black powder and having a relative viscosity of 19.3. The polymer was extruded through a spinneret containing 900 capillaries at a rate of 31.5 kg / h (69.5 lb / hr) per position from a commercial 45-position machine. All these filaments were spun at an extraction rate of 1460 meters / minute (1600 yards / minute) essentially as described in Example 1, except as described, and the spun tow or bundle is collected in a container or canister of sheet. The total denier of the tow was approximately 145,624 (161,840 dtex) and the total number of filaments was 40,500. Fifteen containers or sheet cans from the supply of the spun material were combined together to give a tow or bundle of filaments that is quantified up to 607,500 filaments and a total denier value of approximately 2.2 million (2.4 million dtex). The tow or bundle of filaments was stretched at a stretch ratio of 2.98X in a spray-drawn at 89 ° C with water. The tow or filament bundle was then processed through a filled box folder and then relaxed to 130 ° C to give a final tow denier value of approximately 910,000 (1,011,000 dtex) of the 1.5 dpf fibers (1.7 dtex). A conventional finish was applied to provide a fiber finish level of 0.10% by weight. The tow was collected in a conventional tow box and sent to a spinning mill for downstream processing, the combination with wool and the yarn conversion. The properties of the drawn yarn are shown in Table 10, as in Article A.

B. The poly (ethylene terephthalate) filaments of 5.7 dpf were spun in the molten state at 283 ° C from the polymer containing 1.98 mol% of sodium 5-sulfoisophthalate and dimethyl and having a relative viscosity of 12.7. . The polymer was extruded at a rate of 36 kg / h (80 pounds / h) per position from a commercial 45-position machine through a row containing 741 capillaries at an extraction rate of 1414 yards / minute essentially as described in Example 1, except as indicated, and the tow or bundle of woven yarns was collected in a container or can of sheet. The total denier value of the tow was approximately 189,674 (210,750 dtex) and the total number of filaments was 33,345.

Twelve containers or cans of sheet material were combined to give a tow that is quantified in 400,140 filaments and a total denier value of approximately 23 million (26 million dtex). The tow or bundle of filaments was stretched at a drawing speed of 3.17X in the spray-drawn at 86 ° C with water. The tow or bundle of filaments was then processed through a packed box folder and subsequently relaxed to 135 ° C to give a final tow denier value of approximately 900,000 (1 million dtex) of 2.5 dtex fibers ( 2.25 dpf). A conventional finish was applied to provide a level of finish on the fiber of 0.11% by weight. The tow was collected in a conventional tow box and sent to a spinning mill for downstream processing, wool mixing and yarn conversion. The properties of the drawn yarn are shown in Table 10, as in Article B.

Table 10 As will be apparent from the Examples (and from the comparisons against polyester fibers of the conventional round cross section, which have been the only polyester fibers that have been previously used for the processing of commercially combed wool as it is believed) , an oval-shaped cross section has shown advantages over the round cross section, which have been found to be very surprising. The ability to use and process the fibers of lower pfd value is particularly advantageous, as described above. In comparison with the tow of the mixed dpf fibers, as described in the original application of the same applicant DP-6255, No. 08 / 497,495, filed on June 30, 1995, referred to above, the tows of the present application are easier to manufacture and cheaper to make. The possibility of using variants (see Example X) could also be advantageous.

It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects to which it relates.

Having described the invention as above, property is claimed as contained in the following

Claims (2)

1. A tow or bundle of filaments that is suitable for processing on a worsted or worsted wool system and consisting essentially of continuous polyester filaments of an average concentration per filament of up to 5 dtex, wherein the filaments have a cross section that it has a notched oval shell shape, and the notches run along the length of the filaments, characterized in that the polyester polymer is of a relative viscosity (LRV) of 8 to 12 and the content of the chain brancher it is 0.3 to 0.7% mol.

2. A twine that is suitable for processing on a combed wool or yarn system and which is a continuous twine of discontinuous polyester fibers or wool fibers and discontinuous polyester fibers, where the polyester fibers are of a high concentration average of up to 5 dtex and have a cross-section having a notched oval shell shape, and notches running along the length of the fibers, characterized in that the polyester polymer is of a -relative viscosity (LRV) from 8 to 12 and has a content of the chain brancher from 0.3 to 0.7 mol%.