US3905077A - Process for crimping polyester filament yarn - Google Patents

Process for crimping polyester filament yarn Download PDF

Info

Publication number
US3905077A
US3905077A US476129A US47612974A US3905077A US 3905077 A US3905077 A US 3905077A US 476129 A US476129 A US 476129A US 47612974 A US47612974 A US 47612974A US 3905077 A US3905077 A US 3905077A
Authority
US
United States
Prior art keywords
filaments
yarn
filament
pin
percent
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US476129A
Other languages
English (en)
Inventor
Hans Rudolf Edward Frankfort
Peter Francis Lyons
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
EIDP Inc
Original Assignee
EI Du Pont de Nemours and Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US281972A external-priority patent/US3861133A/en
Priority claimed from GB2315474A external-priority patent/GB1452354A/en
Priority to JP49058909A priority Critical patent/JPS50155717A/ja
Application filed by EI Du Pont de Nemours and Co filed Critical EI Du Pont de Nemours and Co
Priority to US476129A priority patent/US3905077A/en
Application granted granted Critical
Publication of US3905077A publication Critical patent/US3905077A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • D—TEXTILES; PAPER
    • D02—YARNS; MECHANICAL FINISHING OF YARNS OR ROPES; WARPING OR BEAMING
    • D02J—FINISHING OR DRESSING OF FILAMENTS, YARNS, THREADS, CORDS, ROPES OR THE LIKE
    • D02J1/00—Modifying the structure or properties resulting from a particular structure; Modifying, retaining, or restoring the physical form or cross-sectional shape, e.g. by use of dies or squeeze rollers
    • D02J1/22—Stretching or tensioning, shrinking or relaxing, e.g. by use of overfeed and underfeed apparatus, or preventing stretch
    • D—TEXTILES; PAPER
    • D02—YARNS; MECHANICAL FINISHING OF YARNS OR ROPES; WARPING OR BEAMING
    • D02G—CRIMPING OR CURLING FIBRES, FILAMENTS, THREADS, OR YARNS; YARNS OR THREADS
    • D02G1/00—Producing crimped or curled fibres, filaments, yarns, or threads, giving them latent characteristics
    • D02G1/004—Producing crimped or curled fibres, filaments, yarns, or threads, giving them latent characteristics by heating fibres, filaments, yarns or threads so as to create a temperature gradient across their diameter, thereby imparting them latent asymmetrical shrinkage properties

Definitions

  • the present invention is concerned with production of polyester and polyamide filaments'which crimp due to asymmetric shrinkage when relaxed.
  • Filaments which crimp due to asymmetric shrinkage when relaxed have been prepared by a variety of methods.
  • Kilian U.S. Pat. No. 3,050,82l discloses polyester filaments which have been asymmetrically quenched during melt spinning, by blowing cooling air against one side of the filaments as they emerge from the spin neret. When drawn and then relaxed, the filaments will shrink to a greater extent on one side of the filament, but a relatively low crimp frequency is obtained in this manner.
  • Crimpability has been imparted by passing filaments over a sharp edge. This weakens the filament and improvements in the crimp obtained are desirable.
  • the edge-treated side is on the inside of crimp bends.
  • Terumichi Ono et al. U.S. Pat. No. 3,600,271 discloses that a better crimped product is obtained when previously undrawn 6-nylon is drawn over a cylindrical pin heated to about 600C.
  • Yukio Mitsuishi et al. U.S. Pat. No. 3,538,566 teaches that milder conditions must be used for polyester filaments. Lower pin temperatures are used and the filaments are wet when drawn over the pin in theprocess of this patent. The results obtainedat various pin temperatures and filament speeds of 200 to 600 meters per minute indicate that undesirably low crimp frequencies are obtained.
  • 6-nylon carpet yarn of increased voluminosity can be prepared by introducing two crimps separately into a yarn, a latent crimp by asymmetric treatment with a heated pin and a direct crimp by subjecting the yarn to direct crimping treatment by a gear-crimping, a stufferbox crimping, or an air-crimping treatment.
  • the present. invention provides for production of multifilament yarns of filaments which, in the heatrelaxed form, have an especially desirable crimp frequency distribution. Additional advantages of the in- PROCESS 2 vention will become apparent from the specification and drawings.
  • the invention is an improvement over previous processes for preparing crimpable yarns by passing a yarn bundle of filaments, spun from a single synthetic linear organic thermoplastic polymer, in contact with a heated surface to provide asymmetric shrinkage properties on opposite sides of filaments.
  • the improvement of the present invention comprises (a) drawing the filaments to provide the approximate break elongation desired in the product and (b) passing the drawn filaments at high speed in frictional contact with a durable, wear-resistant surface under frictional tension sufficient to generate all of the heat required to provide the desired asymmetric shrinkage properties without otherwise heating the wear-resistant surface.
  • the drawn filaments should be passed in frictional contact with the durable, wear-resistant surface at a speed of at least 900 yards per minute, and more preferably at a speed of at least 2,000 yards per minute. There appears to be no upper limit to thespeeds which can be used but speeds within the range of 1,000 to 4,500 yards per minute are generally used.
  • the yarn filaments must be drawn before the filaments contact the wear-resistant surface in step (b).
  • the drawn filaments preferably have a break elongation of less than 40 percent. Preferably they are drawn so as to have 5 to 25 percent boil-off shrinkage.
  • a preferred process is a coupled spin/draw/pin-texturing process in which the yarn is drawn to have 15 to 40 percent break elongation and 8 to 16 percent boil-off shrinkage prior to contact, in step (b), with a pin having a durable, wear-resistant surface.
  • the temperature of the yarn just prior to the wear-resistant surface should be from 25 to C., although higher temperatures may be used.
  • the filaments must contact the wear-resistant surface under a frictional tension sufficient to generate all of the heat required to provide the desired asymmetric shrinkage properties without otherwise heating the wear-resistant surface.
  • frictional tension is used herein to designate the tension on the filaments immediately after the surface minus the tension on the filaments immediately before the surface. Generally, this value is 0.7 m7 grams per filament; preferably the tension difference is l to 2 g./fil. for polyesters and 4 to 5 g./fil. for polyamides.
  • the filaments usually make frictional contact with the wear-resistant surface for a distance of 0.5 to 15 millimeters.
  • the process is operated so that the filaments are in contact with the surface for a distance of l to 10 millimeters.
  • the durable, wear-resistant surface is provided by a cylindrical pin 3 to 10 millimeters in diameter, but the contact surface can be provided by other means known to the art.
  • the filaments usually contact the surface of the cylindrical pin over an arc of 30 to and preferably between 45 and 90.
  • FIG. 1 is a schematic representation of process and apparatus suitable for continuously melt-spinning drawing and treating filaments in accordance with the invention.
  • FIG. 2 is a schematic representation of process and apparatus for treating previously drawn yarn in accordance with the invention.
  • the filaments may consist of any single composition of linear organic thermoplastic polymer conventionally used for textile filaments and yarns.
  • the single composition may comprise intimate mixtures of polymers and/or copolymers and may contain minor amounts of other additives, such as delusterants, antistatic agents, or other monomeric or polymeric additives.
  • Polyesters and polyamides are preferred polymers.
  • An especially preferred polyester is polyethylene terephthalate (ZGT), as homopolymer or copolymerized with minor amounts of other components.
  • ZGT polyethylene terephthalate
  • Such copolymerized polyesters include poly- (ethylene terephthalate/isophthalate poly(ethylene terephthalate/adipate) and poly (ethylene terephthalate/'(sodium sulfo )-isophthalate).
  • polyesters include poly(tetramethylene terephthalate) and poly (l,4-cyclohexylenedimethylene terephthalate).
  • polyamide polymers that are preferred are hexamethylene adipamide (nylon 6-6) and the polyamide obtained from bis-(para-aminocyclohexyl) methane and dodecane dioic acid.
  • the process of the present invention requires that the filaments must be drawn before being treated asymmetrically. Sufficient drawing is necessary to assure that adequatetension conditions can be maintained when the filaments are subsequently passed in frictional contact with the wear-resistant surface.
  • the drawing is conducted so that the drawn filaments have the approximate break elongation and boil-off shrinkage desired in the product.
  • the break elongation be between 15 and 40 percent, preferably 25 to 35 percent and the boil-off shrinkage be between 5 and 25 percent, preferably 8 to 16 percent.
  • the filaments are passed at high speed in frictional contact with a durable, wear-resistant surface.
  • the temperature of the filaments fed to the surface is generally between 25 and l 10C., although higher temperatures may be used. Care should be taken that each filament contacts the surface in approximately the same manner.
  • the bundle of filaments is not twisted and the filaments pass over the surface as a single layer of individual filaments.
  • the frictional contact of the filaments with the surface is sufficient to generate enough heat to asymmetrically modify the shrinkage properties of the filaments. No other heating of the wear-resistant surface is necessary.
  • the tension on the filaments undergoes a distinct change due to the frictional work that is done. This change in tension is equal to tension on the filaments immediately after passage over the surface 4 minus the tensionimmediately before passage over the surface.
  • Tension differences of 0.7 to 7 grams per filament are useful, with 1 to 2 g./fil. for polyesters and 4 to 5 g./fil. for polyamides being preferred. These tension differences generally apply to filaments of about 1.5 to 10 denier.
  • the filaments usually make frictional contact with the wear-resistant surface for a distance of 0.5 to 15 millimeters, and preferably contact the surface for a distance of l to 10 millimeters.
  • the wear-resistant surface is a curved surface, most conveniently provided by a cylindrical pin. Pin diameters of about 1 to 15 millimeters are suitable; 3,to 10 millimeters, are preferred.
  • the are over which the filaments usually contact the pin surface is between 30 to 180, and preferably between 45 and Durable, wear-resistant surfaces are needed for satisfactory long-term continuous operation.
  • Ceramic pins of the type commonly used for guides and draw pins in textile processes are suitable. The use of Alsimag, glass and stainless steel pins is illustrated in the Examples. Other metals with durable surfaces are also satisfactory.
  • the variables discussed above preferably are adjusted so that the value of AT max calculated by the following formula is at least C. and usually below 300C:
  • the AT max parameter is related to the asymmetric temperature distribution that is imposed' on the filament by the frictional heat generation and is referred to herein as the temperature rise parameter.
  • ATmax 1.92 (f -f Especially preferred operating conditions are obtained in the practice of the present invention when AT max values of at least C. are used with polyester filaments and of at least 200C. are used with polyamide filaments.
  • FIG. 1 A continuous process for preparing asymmetrically treated filaments in accordance with the present invention is shown in FIG. 1.
  • Filaments are melt-spun from spinneret 11 and allowed to cool as they descend from the spinneret. The filaments then converge and which have a considerably higher surface speed than I the feed rolls to draw the yarn.
  • a traversing mechanism 16 is provided for guiding the filaments onto the draw rolls. When activated, the mechanism 16 varies the.
  • the filaments can be guided to the texturing pin by an adjustable idler roll I (not shown) to facilitate changing the wrap angle 0 at I the texturing pin in order to increase or decrease the length of pin-filament contact.
  • the filaments pass from the pulling rolls 18 over a postdraw finish roll 19 to wind-up 20, which cross-winds the product under a tension that is best measured shortly after the postdraw finish roll.
  • Crimp is developed in the above product by a subsequent heat relaxation treatment.
  • the processes may be combined to produce a crimped product in one continuous operation.
  • the filaments may be passed through heating means on a conveyor in relaxed condition and then cooled prior to being wound up.
  • the melt-spinning, drawing and pin-texturing sequence can be split in various ways.
  • the melt-spinning can be a separate operation.
  • a conventional melt-spinning and drawing process can be used to produce yarn which is later pin-textured in a separate operation.
  • FIG. 2 illustrates such a separate operation wherein untwisted, drawn and packaged yarn is fed over-end to the pin-texturing treatment.
  • the yarn passes from package 21 through tension gate 22- and over roller 23 to a pair of feed rolls 24.
  • the yarn makes several wraps about the pair of feed rolls, proceeds to a pair of stretch rolls 25, makes several wraps about the pair of stretch rolls, passes over texturing pin 26 at a wrap angle 0, and proceeds over roller 27 to wind-up 28.
  • the yarn passing over the texturing pin may be an inner wrap, i.e., the yarn passes from the pin back to the stretch rolls. Alternatively, the yarn may pass from the pin to separate pulling rolls without returning to'the stretch rolls".
  • the filaments are-fed to they frictional contact surface (e.g., a pin) by feed rollsand withdrawn therefrom by takeup rolls
  • the filaments usu' ally are stretched by no more than 10 percent and preferably by no more than 5 percent.
  • a stretch of substantially zero :(i-.e.”, no stretchinglican be used satisfactorily in the pin-texturing 'step.
  • 6 polyester yarns in a continuous process it is preferred to operate with a stretch of between 2 and 5 percent.
  • the multifilament yarns produced in accordance withithe above-described processes of the invention may be of any conventional denier/filament count. Generally, yarns of about 35 to 250 denier having 10 to 200 filaments are suitable. Yarns having 17 to 50 filaments are..preferred. Yarn counts of /34 to 190/34 are especially preferred. Filament deniers of l.510 are suitable, but 2-5 are preferred.
  • Crimp may be developed in the yarns produced according to the invention by any of the many wellknown conventional heat-relaxation treatments. In general, these treatments allow the yarn to shrink freely while exposed to hot water, steam or dry heat. In the I method used herein for comparing the crimp frequencies of filaments, the filaments are suspended free of tension in an oven through which hot air at 180C. is gently circulated for five minutes and then the filaments are allowed to cool while still free from tension. Filaments which have been relaxed by other methods are. also retreated by this test method to standardize crimp measurements.
  • the process of the present invention also provides a particularly useful, novel polyester filament which when heat-relaxed has an especially desireable crimp frequency distribution. Yarns made of such filaments have additional advantages in use, which will be discussed below.
  • This product of the invention is a textile filament having asymmetric properties and an abraded surfaceextending along one side of the filament, and consisting of a single synthetic linear polyester composition: The filament has a modified minor portion'distinguishable by a difference in refractive index, which extends substantially continously along the abraded side of the filament.
  • the continuity of this minor portion is such that less than 5 percent, preferably less than 3 percent, of the filament length is occupied by discontinuities longer than millimeters and the average length of all discontinuities is less than 2 millimeters, preferably less than 1.5 mm.
  • the number of discontinuities longer than 2 mm. is usually less than 30 percent of the total number of all discontinuities and is preferably less -than 15 percent.
  • the minor portion occupies 3 to 20 percent, preferably 4 to 15 percent, of representative cross-sectional areas along the filament and is usually 1 to 3 microns, preferably 1.4 to 2.6 u, in thickness, measured from the abraded surface.
  • the filament is capable of crimping when given a heat-relaxation treatment for 5 minutes in air at 180C.
  • the abraded surface of the filament is generally on the outside of crimp bends and is marked by closely spaced, parallel ripples which extend transversely with respect to the filament length. These ripples are clearly visible when the filament is viewed under high magnification.
  • A'heatrelaxed product of the invention is as defined above and further characterized by crimp frequency values, measured after a heat-relaxing treatment for 5 minutes in 180C. air and normalized for 2.5 denier per filament, which average at least 10, preferably 25 to 60, crimps per filament inch with a percent coefficient of variation of less than 30, preferably less than 20.
  • crimp frequency values measured after a heat-relaxing treatment for 5 minutes in 180C. air and normalized for 2.5 denier per filament, which average at least 10, preferably 25 to 60, crimps per filament inch with a percent coefficient of variation of less than 30, preferably less than 20.
  • Preferablyatleast 95 percent of the filament length has greater than 15 crirnps per filament inch and the crimp frequency distribution for the middle percent is numerically equal to or less than said average (usually from 0.4 to 0.9 times the average crimp frequency value
  • at least 90 percent of the filament 7 length has greater than crimps per inch.
  • Crimp frequencies are expressed herein as crimps per filament inch, rather than crimps per straight line inch of crimped length.
  • the measurement is accomplished by extending the filament under a load sufficient to straighten the crimps without stretching the filament, marking l-inch (2.54 cm.) distances along the filament, then removing the load to allow recrimping, and counting the crimps between l-inch (2.54 cm.) marks.
  • the measured crimp frequency values are multiplied by V d/2.5, where d is the denier per filament after 180C. treatment, to obtain normalized crimp frequency values. If the percent shrinkage (S) in the 180C. oven-relaxing treatment is known, the value of d can be determined by multiplying the unrelaxed denier per filament by (1 S/lOO).
  • a characteristic abraded surface which extends sub stantially continuously along one side of the filaments of this invention, provides a qualitative distinction from prior art filaments that have been modified in different ways to impart crimp.
  • the location of modified filament portions in heat-relaxed filaments is indicated by closely spaced, parallel ripples crossing the filaments.
  • FIG. 3 shows the crimp frequency distributions of products produced as described in Example 1 below and then heat-relaxed for 5 minutes in 180C. air.
  • the nor malized crimp frequency in crimps per filament inch is indicated on the abscissa, and the percent of the fila-. ment length having greater crimp frequencies is indicated on the ordinate.
  • the distribution curves are numbered to correspond to yarn numbers.
  • the graph can be used to ascertain the percent of the filament length which has a crimp frequency greater than any given value.
  • the average crimp frequency is the value where the 50 percent ordinate value intersects the curve.
  • the crimp frequency distribution for the middle 90 percent is the minimum crimp frequency for 5 minus the minimum crimp frequency for 95 percent; which will be abbreviated R R Woven and knit fabrics containing relaxed yarns of this invention have desirable bulk aesthetics, performance and uniformity.
  • yarns of the type described in Example [-3 below when relaxed in a hot air jet and then woven into fabrics, yield fabrics that have a high degree of suppleness and liveliness; warpknits from similarly relaxed yarns have a soft hand, high bulk, and excellent dye-uniformity.
  • Double-knit fabrics prepared from relaxed yarns of Example I, yarn sample 2, have a high, firm bulk and excellent wash-wear performance, wrinkle-resistance, and dye-uniformity.
  • Suitable filaments for such yarns are between 1 and 7 denier per filament.
  • the yarns of the present invention can also be cut into staple lengths and converted to yarns or used as filling, as in pillows, after developing the crimp.
  • EVALUATION PROCEDURES Photomicrographs of Filament Surfaces A scanning electron microscope is used to examine the nature of the abraded surface of the filaments.
  • a short sample (about 1.9 cm. long) of yarn is mounted on a standard Stereoscan stub (1.9 cm. diameter aluminum stub).
  • Two strips (0.32-cm cm. X 0.63-cm.) of double-faced adhesive tape are fixed l.27-cm. apart and parallel to each other on the stub surface.
  • the sample of yarn is lightly teased to separate thefilaments and each yarn end is fixed to one strip of the adhesive.
  • the final step of specimen preparation involves the vacuum evaporation of a 60/40 Au/Pd coating onto the surface of the sample and stub which insures electrical continuity over the entire stub.
  • the thickness of this coating is estimated to be of the order of 300-400 A which is below the level of resolution of the scanning electron microscope used; thus, the coating is not seen when viewing filaments by this technique.
  • the stub is placed in the specimen holder and after evacuation of the specimen chamber, the specimen is viewed in the scanning electron microscope.
  • Typical viewing conditions are 20 KV electrons with a beam current of 200 ;.:.amps, and a specimen tilt of 30 relative to the impinging electron beam.
  • micrographs are recorded at, e.g., 200, 500, 1,000 and 2,000X magnifications. This series of magnifications includes a sufficiently low magnification to illustrate the position of the modified surface relative to the crimp and a sufficiently high magnification to reveal details of the modified surface.
  • unrelaxed filaments of the present invention exhibit a frictionally modified surface running along the filament length; in the relaxed filaments, this surface can be seen to be present along the outside of the crimp bend and can also be seen to have a plurality of ripples. These ripples are visible on the abraded surface and run transverse to the filament length.
  • the modified surface In the relaxed filaments that have been jet-screen treated (e.g., as in Example 11 below), the modified surface also runs generally on the outside of crimp bends, but may occasionally be seen on the inside where secondary folds have been imposed on sections of the filament by jet-screen impact.
  • Continuity of the Modified Portion Interference microscopy is used to determine the continuity of the modified portion along filament length Z, where Z is taken as 40 mm. times the number of filaments in the yarn for any yarn having 34 filaments. For other yarn counts, a total of 1,360 mm., distributed uniformly across the yarn, is viewed.
  • a 60 mm. length is cut from the yarn.
  • the individual filaments are separated.
  • Each 60-mm. long filament is taped on a glass slide so that it lies straight.
  • the slide is immersed in Refractive Index Fluid of an index of refraction (n) which matches the index of refraction (n perpendicular) of the unmodified portion of the filament for light vibrating perpendicular to the fiber axis (e.g., a fluid of n 1.540 is used for polyethylene terephthalate).
  • n index of refraction
  • the filament after immersion in the fluid, is then covered with a second glass slide and the assembly is placed on the stage of the interference microscope. The assembly is advanced across the viewing area so that a continuous 40 mm.-length is viewed at 200X.
  • a modified portion is detected by interference contrast (i.e., the modified portion will be of different color than the remainder of the filament) or by fringe field (i.e., a fringe shift indicates a change in index of refraction going from modified to unmodified areas of the filament). Only those sections where a The following are determined:
  • W sum of the lengths of discontinuities greater than 2 mm., expressed in mm.
  • a cross-section of the yarn sample is suitably prepared for microtome sectioning, e.g., a yarn bundle is mounted in a Beem capsule and embedded with epoxy (Maraset from Marblette Corp.). After trimming the cured stub, approximately 6 micron thick sections are obtained using a rotary microtome (Spencer Model 860) with a steel blade. The sections are placed onto the two halves of a cut microscope slide (insures constant thickness for a two beam Leitz Transmission Interference Microscope). The two specimen slides are completed by immersing the sections in refractive index oil (Cargille Index of Refraction Fluid N 1.530) and covering iwth microscope cover slips.
  • refractive index oil Cargille Index of Refraction Fluid N 1.530
  • One specimen slide is placed onto the reference beam stage and the other slide is placed onto the sample beam stage of the two beam Leitz Transmission Interference Microscope.
  • the specimen section is viewed at 500 magnification. Following the alignment procedures, thefringe field is obtained in the field of view in white light. The fringes are then fluffed out to obtain interference contrast, i.e., the fringes are taken to their maximum separation.
  • the specimen section is brought into sharp focus and the index variation across the textured filament cross-section is recorded on color film as the retardation or color difference across the filament section.
  • the procedure can be carried out in monochromatic illumination and recorded on black and white film.
  • the procedure described above is performed without the analyzer in the optical system and is used as a qualitative detection technique for presence of the modified portion of different refractive index.
  • Thickness of the modified portion is determined from l,OO0 micrographs of cross-sections by measuring with a ruler the thickness on three cross-sections at three points each, and averaging the nine values. In these measurements 1 mm. l u.
  • the three points measured on the photomicrograph are (l) the thickness at the center of the modified portion and (2) and (3) the thickness near each of the extremes of the modified portion, measured at a distance of about 1 mm. from each extreme.
  • the width of the modified portion at its widest point and the diameter of the filament are also measured on l,OO0 micrographs of cross-sections. Four or five cross-sections per sample are analyzed and the average of the four or five determinations is recorded.
  • Crimp Frequency Distribution For a yarn having at least 17 filaments, a 50-cm. length of yarn is cut from the yarn to be tested, and 17 filaments, taken at random, are carefully separated from the cut length, taking care not to stretch the filaments.
  • One filament at a time is relaxed as follows: The filament is suspended by attaching both ends to a glass rod at a sufficient distance apart to permit the filament to shrink and crimp fully without becoming taut; this is done, e.g., by attaching masking tape or a suitable clip to each end of the filament and clipping each end to the rod.
  • the rod may be permanently mounted in the oven or placed in the oven, with the filament already attached to it. Hot air at C.
  • a suitable oven for this test is Electric Hotpack Co., Inc., Model 1354.
  • the thusly suspended filament is free to relax.
  • the filament is removed from the oven and is carefully placed in a relaxed condition on a velvet board.
  • the oven is allowed to come back to 180C. (e.g., 5 minutes) before the next specimen is placed in the oven. This is repeated until all 17 filaments have been relaxed, individually.
  • each relaxed filament is then taped to one end of a clear plastic straight-edge which is marked in l-inch (2.54 cm.) intervals.
  • a weight sufficient to straighten the crimps without stretching the filament, is taped to the free end of the filament.
  • a weight sufficient to straighten the crimps without stretching the filament.
  • the straight-edge is lifted to a vertical position, allowing the filament to hang freely under the tensioning weight.
  • the filament is then taped to the straight-edge near the weighted end, while under tension. With a black felt-tipped marking pen, twelve consecutive l-inch sections are marked off on the filament. The filament is then removed and taped at its ends, re-
  • the yarn contains less than 17 filaments total, a sufficient length of yarn is used, so that the number of filaments times the length equals 204 inches (5l8-cm.).
  • the number of one-inch sections in each of a series of crimp ranges (-5 cpi, 6-10 cpi, 1 1-15 cpi, etc., in increments of cpi/range) is counted and the percent of filament length within a given crimp range is calculated by:
  • Number of l-inch sections in given crimp range X 100 204 sections Data are reported in terms of filament length present, having a crimp frequency greater than a given level, using as levels the upper limit of each crimp frequency range, i.e., 5 cpi, 10 cpi, cpi, etc.
  • the respective observed crimp frequency values are multiplied by V d/2.5 to obtain normalized crimp frequency values, where d is the denier per filament after the heatrelaxing treatment in 180C. air for 5 minutes. Any accurate method can be used for determining 1.
  • the method used herein is to multiply the denier per filament before the heat-relaxing treatment by (l 1 S/lOO), where S is the percent shrinkage calculated from yarn lengths before and after the heat-relaxing treatment when measured under sufficient tension to just straighten any crimps without stretching the yarn (a tension of grams is suitable for 34-fi1ament yarns in the Examples unless otherwise specified).
  • the crimp frequency distribution for the middle percent is defined as R5"R95, where R is the value read from the graph at the 5 percent level and R is the value read at the 95 percent level.
  • R is the value read from the graph at the 5 percent level
  • R is the value read at the 95 percent level.
  • the ratio of R R to the average crimp frequency is equal to or less than 1.
  • the percent coefficient of variation is defined as the standard deviation of the individual determinations of crimp frequency (F), times and divided by the average crimp frequency in crimps per inch.
  • the standard deviation is calculated by the formula:
  • a yarn finish is applied by conventional means (i.e., lst and 2nd finish-applying rolls referred to in the discussion of FIG. 1).
  • This finish referred to hereinafter as finish A, is a 3.9 percent aqueous mixture containing 49 parts of isocetyl stearate, 24.5 parts of sodium di-(2- ethyl-hexyl)sulfosuccinate, 24.5 parts of the condensation product of 1 mol of stearyl alcohol with 3 mols of ethylene oxide, 1 part of triethanolamine and 1 part of oleic acid.
  • the total amount of finish applied to the filaments is approximately 0.3 i 0.1 weight percent finish on yarn after drying, based on the weight of yarn.
  • finish B is an aqueous mixture containing 20.5 parts of sulfated peanut oil, 1.8 parts of diethylene glycol, 1.8 parts of KOH, 62.6 parts of the ester formed from l-butanol and a 45-55 mixture of stearic and palmitic acids, 8.2 parts of oleic acid, 3.4 parts of triethanolamine, and 1.7 parts of ortho phenylphenol.
  • finish B is an aqueous mixture containing 20.5 parts of sulfated peanut oil, 1.8 parts of diethylene glycol, 1.8 parts of KOH, 62.6 parts of the ester formed from l-butanol and a 45-55 mixture of stearic and palmitic acids, 8.2 parts of oleic acid, 3.4 parts of triethanolamine, and 1.7 parts of ortho phenylphenol.
  • finish B is an aqueous mixture containing 20.5 parts of sulfated peanut oil, 1.8 parts of diethylene glycol, 1.8 parts of KOH, 62.6 parts of the
  • Alsimag is a registered trademark in the US. for pressed and extruded steatite thread guides, beryllia ceramics, and leachable ceramic cores. Steatite is a mixture of clay, talc and alkaline earth oxides.
  • the Alsimag pins used in the Examples are made by American Lava Corp. of Chattanooga, Tenn. Pins having friction coefficients of 0.2-1.2 are suitable for use in the invention; coefficients of 0.4-0.8 are preferred.
  • EXAMPLE I This Example illustrates the production of six polyester yarns in accordance with the present invention. Process conditions are summarized in Table I. The crimp characteristics of the resultant yarns are presented in Table I1. Crimp frequency distributions for the first five yarns are plotted in FIG. 3.
  • All of the yarns of this example, except yarn 5 are prepared by a continuous process in which polyethylene terephthalate polymer is melt-spun, drawn and pintextured as shown in FIG. 1.
  • the process for yarn 5, illustrated in FIG. 2 involves the use of previously meltspun, drawn and packaged commercial semi-dull polyethylene terephthalate filaments.
  • These yam-5 fila' ments, prior to pin texturing, formed a 34-filament, 70 denier yarn having a boil-off shrinkage of about percent and a break elongation of about 36 percent Finishes A and B were applied to yarn 5 prior to pin texturing, as described above.
  • the draw rolls are located in a temperature-controlled en- 14 closure, called a draw box. Since the filaments in this example lose very little heat in traveling from the draw box to the texturing pin, the yarn temperature at the feed pin is listed in Table I as being at the same temperature as the draw box.
  • Yarn 2 which as indicated in Table l, is produced in a similar manner to yarn 1, but is further processed by ajet-screen-bulking step. After pin-texturing, the yarn is fed at about 3000 yards/minute (2740 meters/minute) at a temperature of about 125C. to a hot-air jet device which deposits the yarn on a screen drum as i1- lustrated in Clendening US. Pat. No. 3,217,386.
  • the jet device is of the type disclosed in Coon US. Pat. No. 3,525,134 and is supplied with hot air at 335C. and pounds per square inch (7kg/cm gauge pressure.
  • the jet device comprises a longitudinal yarn passage terminating in a short length having a width d,- of 0.033- inch (0.085 cm.) and a depth of 0.030-inch (0.076 cm.); a throat region having a width d, of 0.045-inch (0.114 cm.); an expanding treatment chamber whose sides diverge at an angle B of 45 from the throat region to a width d of 0.22-inch (0.56 cm.) at the chamber exit; and dual fluid conduits, each having a width d, of 0.025-inch (0.064 cm.), disposed on either side of the yarn passage and intersecting the throat region at an angle a of 30.
  • the dual fluid conduits and the yarn treatment chamber have the same depth of 0.060-inch (0.1-52' cm.)
  • the heated air supplied to the jet device forwards the yarn through the treatment chamber, plasticizes it and propels it against a screen surface on a rotating relaxing drum.
  • the screen drum surface is of 40-mesh, located 0.050-inch (0.127 cm.) from the jet exit and revolving at 700 feet per minute (213 meters/minute). Residence time on the drum is 0.12 second.
  • the treated yarn is taken from the screen drum at about 2,220 yards per minute'(2,0l0 "meters/minute) by a pair of rolls and proceeds at 20 grams tension to a wind-up for packaging.
  • Table 11 lists the properties and FIG. 3 shows the crimp frequency distribution of the final product (i.e., the pin-textured product that has also been jet screen bulked).
  • EXAMPLE II This example describes another embodiment'of the invention in which polyester filaments which have been melt-spun at relatively high speeds are pin-textured and then jet-screen bulked. Process conditions for the drawing and pin-texturing steps are given below and in Table l; The crimp characteristics of the final product are summarized in Table II.
  • Polyethylene terephthalate of 19.5 relative viscosity and containing about 0.3 percent, by weight, of TiO delusterant is melt-spun at 284C. through a spinneret having 34 round holes, each hole having a diameter of 0.01 l-inch (0.028 cm.) and a length of 0.020-inch (0.051 cm.).
  • the freshly spun filaments are quenched with air at 23C. in crossflow against the filaments and then passed through a guide, past a finish roll to a pair of puller rolls, situated 188 inches (4.78 meters) below the spinneret and revolving at a peripheral speed of 3,398 ypm (3,107 meters/minute).
  • the yarn wraps around these rolls and, subsequently, passes around rolls moving at 3,403, 3,409, and 3,413 ypm, (3,112, 3,117, and 3,121 meters/minutes) respectively, which maintain tension on the yarn.
  • the yarn then passes through an interlace jet and to a second finish roll and is then wound up at 3,41 1 yards per minute (3,1 19 meters/minute) to form a package.
  • the interlace jet is of the type described in Bunting et al. US. Pat. No. 3,1 15,691.
  • the interlace jet produces an interlace pin count, as measured according to Hitt US. Pat. No. 3,290,932, of about cm.
  • Finish is applied at first and second finish rolls in an amount of 0.50 percent, based on the weight of the fiber.
  • the finish is of the general type described in U.S. Pat. No. 3,594,200 to Cooley and Finch.
  • lts composition is as follows: 28 parts of coconut glycerides, 37 parts (on a wet basis) of sulfated peanut glycerides having a 20 percent water content, parts of Gafac PE- 510, i.e., an acid phosphate of ethoxylated nonylphenol as depicted by the formula at Col. 2, line 5 of U.S. Pat. No. 3,594,200, and 10 parts of Shell 277 (a mixture of paraffinic and alicyclic hydrocarbons). To this mixture is added enough 45% KOH to give a pH of 6.5.
  • the yarn obtained in this fashion is a 247 denier-34- filament yarn having a tensile strength of 2.47 grams per denier, an elongation of 129.1 percent, and an initial modulus of 30.94 grams per denier.
  • An X-ray pattern of the yarn shows that it is amorphous, having no measurable crystallinity.
  • the orientation angle is 14 and the density of the filaments is 1.342 grams per cc.
  • the as-spun yarn from its package is then led to a pair of feed rolls rotating at a peripheral speed of 668 yards per minute (61 l meters/min.) making 7-8 wraps about the rolls then passed in sliding contact with ice cold metal finish roll rotating in an ice/water bath.
  • From the finish roll the cooled yarn travels a distance of less than about 8 inches to a T-pipe having a yarn passageway with a diameter of Aa-inch (1.59 cm.) and length of 10 inches (25.4 cm.) into which atmospheric steam is fed.
  • the yarn passes through the pipe, it is subjected to the 95-100C. mixture of hot water and atmospheric steam in the pipe. Steam exits from the pipe at the entrance and exit of the yarn passageway.
  • the yarn passes a distance of less than about 8 inches (20.3 cm.) to a second ice cold metal finish roll rotating in bath containing a mixture of ice and water.
  • the cooled yarn then passes to a pair of draw rolls rotating at a peripheral speed of 1,499 yards per minute, (1371 meters/min.) making 8-9 wraps about the rolls.
  • the yarn in its passage from the feed rolls to the draw rolls, the yarn is drawn 1.94X.
  • the drawn yarn has an elongation of about 13-14 percent.
  • the yarn then passes from the draw rolls over a Type 3 unheated AlSi- Mag 192 texturing pin.
  • the AlSiMag pin is stationary and the yarn passes over it in frictional contact with it an an angle of 90". From the pin the yarn passes to rolls rotating at a speed of 1,518 yards per minute (1,388 meters/min.) making 5-6 wraps about the rolls and then to a package.
  • Tension on the yarn during drawing is 190 grams.
  • Yarn tension measured in the same way before and after the pin is 50-90 grams (before) 200-230 grams (after).
  • the calculated AT max parameter for this process is 273C.
  • the properties determined on the pin-treated yarn are as follows:
  • the yarn is then unwound from a package and subjected to a jet/screen relaxing treatment under the following conditions:
  • the yarn is led to a set of feed rolls rotating at a peripheral speed of 1,455 yards per minute, (1,330 meters/min.) making 12 wraps about the feed rolls. From the feed rolls the yarn passes into a jet.
  • the jet device used is of the type described in Yngve US. Pat. No. 3,638,291. Referring to FIG. 2 of the Yngve patent, the dimensions of the jet are as follows:
  • the jet is supplied with steam at 25 to 28 psi (1.76 to 1.97 kg/cm gauge and 300 to 305C. From the jet the yarn is impacted against a screen mounted on drum moving at a peripheral speed of 7 yards per minute (6.4 meters/min), the drum being a 3 /z-inches (8.9-cm.) wide, 15-inch (38.1-cm.) diameter drum having a mesh screen on its surface. An accumulated mass of yarn travels for a distance of about 15 inches (38.1 cm.) along the drum circumference. From the drum the yarn passes over guide rolls to a wind-up where it is wound up at about 1,100 yards per minute (1,006 meters/min) The untwisted yarn has the following properties:
  • a sample of the yarn is then knit into a Swiss-pique fabric (18-cut).
  • the fabric has good bulk and desirable hand, texture and appearance.
  • EXAMPLE 111 This example illustrates pin-texturing of polyester filaments in five continuous high speed process embodiments of the invention, in which several process parameters were varied; for example, pin composition, texturing speed from 1,300 to 2,800 yards/minute (1,189 to 2,560 meters/min.) and pin contact length. This series of runs, along with those of the other examples and numerous other data, were useful in developing the AT max parameter for defining preferred operating conditions of the invention.
  • EXAMPLE IV This example illustrates the process of the invention with two types of multifilament polyamide yarns.
  • Yarn A is Zytel 101, made'from polyhexamethylene adipamide (6-6 nylon) of 45 relative viscosity.
  • Yarn B is made from the polyamide, called PACM-l2, which is obtained from bis-(para-aminocyclohexyl)methane and dodecane dioic acid.
  • the filaments are pin textured on unheated glass rods (Type Each polyamide yarn is spun, drawn and wound up Yarn A Yarn B 6-6 Nylon PACM-l2 Tenacity(gpd.) 5.6 3.5 Elongation( 7:) 22 24 Modulus(gpd.) 3 1 35 Denier 130 227 Density 1.1295 1.0802 Orientation Angle() 16 32 Crystallinity Index 48 5
  • each yarn is passed over two sets of rolls and then the fully-drawn yarn is passed over a glass pin to a third set of rolls. Passage over the glass pin frictionally modifies the yarn and imparts latent crimp.
  • l-2 and 11 are samples that were also jet-screen bulked.
  • Crimp is given in crimps per 2.54 cm. of filament length.
  • a process as defined in claim 2 wherein the filament speed is 1,000 to 4,500 yards per minute.
  • a process as defined in claim 3 wherein the dura ble, wear-resistant surface is provided by a cylindrical pin 3 to 10 millimeters in diameter.
  • step (a) the drawn filaments are fed from step (a) to step (b) at a temperature of 25 to 100C.
  • f and f are the average tensions on the filaments immediately before and after frictional contact with the wear-resistant surface, in grams per filament; V is the average speed of the filaments contacting the surface, in centimeters per second; L is the frictional contact length between the filaments and the surface, in centimeters; k is the thermal conductivity of the filaments, in cal./cm.sec.C.;d is the specific heat of the filaments, in cal./g.C.; and a is the denier per filament.
  • a process as defined in claim 1 which is a coupled spin/draw/pin-texturing process wherein the yarn is drawn to have l5 to 40 percent break elongation and 8 to 16 percent boil-off shrinkage.
  • a process for treating multifilament yarn to impart asymmetric shrinkage properties to drawn yarn filaments of denier per filament (d) and consisting of a single synthetic linear polyester composition which comprises passing the drawn filaments at a high speed (V) in frictional contact with an unheated ceramic pin for a frictional contact length (L) of 0.05 to 1.5 centimeters under tension conditions which apply a filament stretch of 2 to 5 percent, said pin having a coefficient of friction of 0.2 to 1.2 and said filaments having a temperature of 25 to C. just prior to contact with the pin, the values of said variables'being such that the temperature rise calculated by the following formula is at least C:
  • f and f are the average tensions on the filaments immediately before and after frictional contact with the pin.

Landscapes

  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)
US476129A 1972-08-18 1974-05-31 Process for crimping polyester filament yarn Expired - Lifetime US3905077A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP49058909A JPS50155717A (enrdf_load_stackoverflow) 1972-08-18 1974-05-27
US476129A US3905077A (en) 1972-08-18 1974-05-31 Process for crimping polyester filament yarn

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US281972A US3861133A (en) 1971-12-22 1972-08-18 Production of highly crimped polyester yarn
GB2315474A GB1452354A (en) 1972-08-18 1974-05-23 Multifilament yarns
JP49058909A JPS50155717A (enrdf_load_stackoverflow) 1972-08-18 1974-05-27
US476129A US3905077A (en) 1972-08-18 1974-05-31 Process for crimping polyester filament yarn

Publications (1)

Publication Number Publication Date
US3905077A true US3905077A (en) 1975-09-16

Family

ID=27448586

Family Applications (1)

Application Number Title Priority Date Filing Date
US476129A Expired - Lifetime US3905077A (en) 1972-08-18 1974-05-31 Process for crimping polyester filament yarn

Country Status (2)

Country Link
US (1) US3905077A (enrdf_load_stackoverflow)
JP (1) JPS50155717A (enrdf_load_stackoverflow)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3487199A (en) * 1968-01-10 1969-12-30 Hamlin Products Inc Portable electric cooker
WO1996016206A1 (en) * 1993-06-29 1996-05-30 E.I. Du Pont De Nemours And Company Improvements in continuous filaments, yarns, and tows
US6038847A (en) * 1998-08-27 2000-03-21 Nan Ya Plastics Corporation Process for manufacturing different shrinkage microfiber texture yarn
US20040258834A1 (en) * 2000-09-19 2004-12-23 Honeywell International Inc. High speed yarn finish application

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2974391A (en) * 1955-11-30 1961-03-14 Ici Ltd Process and apparatus for making crimped filaments
US3115744A (en) * 1959-07-24 1963-12-31 British Nylon Spinners Ltd Process for the manufacture of crimped yarn
US3226792A (en) * 1957-04-16 1966-01-04 English Rose Ltd Method and apparatus for crimping yarn
US3317978A (en) * 1964-08-28 1967-05-09 Monsanto Co Stretch yarn texturing process and apparatus
US3358345A (en) * 1958-01-13 1967-12-19 Techniservice Corp Process and apparatus for crimping strands
US3379809A (en) * 1961-11-24 1968-04-23 Ici Ltd Process for drawing and crimping yarn
US3816992A (en) * 1971-12-22 1974-06-18 Du Pont Crimped polyester filament yarn and process for making same

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2974391A (en) * 1955-11-30 1961-03-14 Ici Ltd Process and apparatus for making crimped filaments
US3226792A (en) * 1957-04-16 1966-01-04 English Rose Ltd Method and apparatus for crimping yarn
US3358345A (en) * 1958-01-13 1967-12-19 Techniservice Corp Process and apparatus for crimping strands
US3115744A (en) * 1959-07-24 1963-12-31 British Nylon Spinners Ltd Process for the manufacture of crimped yarn
US3379809A (en) * 1961-11-24 1968-04-23 Ici Ltd Process for drawing and crimping yarn
US3317978A (en) * 1964-08-28 1967-05-09 Monsanto Co Stretch yarn texturing process and apparatus
US3816992A (en) * 1971-12-22 1974-06-18 Du Pont Crimped polyester filament yarn and process for making same

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3487199A (en) * 1968-01-10 1969-12-30 Hamlin Products Inc Portable electric cooker
WO1996016206A1 (en) * 1993-06-29 1996-05-30 E.I. Du Pont De Nemours And Company Improvements in continuous filaments, yarns, and tows
US6038847A (en) * 1998-08-27 2000-03-21 Nan Ya Plastics Corporation Process for manufacturing different shrinkage microfiber texture yarn
US20040258834A1 (en) * 2000-09-19 2004-12-23 Honeywell International Inc. High speed yarn finish application

Also Published As

Publication number Publication date
JPS50155717A (enrdf_load_stackoverflow) 1975-12-16

Similar Documents

Publication Publication Date Title
US4301102A (en) Self-crimping polyamide fibers
US4245001A (en) Textile filaments and yarns
US4093147A (en) Flat nylon 66 yarn having a soft hand, and process for making same
US4496505A (en) Process for the production of a polyester fiber dyeable under normal pressure
US3623939A (en) Crimped synthetic filament having special cross-sectional profile
US5750215A (en) High speed process for making fully-oriented nylon yarns and yarns made thereby
US4332761A (en) Process for manufacture of textile filaments and yarns
US4096226A (en) Integrated spin-draw-texturizing process for manufacture of texturized polyamide filaments
US3861133A (en) Production of highly crimped polyester yarn
US4123492A (en) Nylon 66 spinning process
CA1107472A (en) Textured yarn and process
FI58358C (fi) Foerfarande foer framstaellning av texturerat polyestergarn
US4343860A (en) Self-crimping polyamide fibers
US4364998A (en) Spunlike yarns
US3949041A (en) Method for texturing synthetic filament yarn
EP0009883B1 (en) Self crimping yarn, process for producing a self crimping yarn, and textured yarn having a wool-like hand
US3816992A (en) Crimped polyester filament yarn and process for making same
US3905077A (en) Process for crimping polyester filament yarn
US4228120A (en) Process for nylon 66 yarn having a soft hand
JPS5817292B2 (ja) テクスチヤ−ドカコウシオ セイゾウスルタメノ ボウシエンシンテクスチヤ−ドカコウホウホウ
US4583357A (en) Partially oriented nylon yarn and process
JP2003518562A (ja) ポリマーの紡糸延伸法
US4167847A (en) Bulky yarn and method for producing the same
EP0013498B1 (en) Process for producing self-crimping yarns, multifilament yarns containing latent crimp filaments, and multifilament yarns containing developed crimp filaments
JPS60209013A (ja) ポリエステル繊維の製造方法