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
  • D02J1/221—Preliminary treatments
• • D—TEXTILES; PAPER
  • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
  • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
  • D01D5/00—Formation of filaments, threads, or the like
  • D01D5/20—Formation of filaments, threads, or the like with varying denier along their length

Definitions

• 264-167 8 tClaims ABSTRACT OF THE DISCLOSURE A process for the production of a spun continuous filament synthetic yarn having variable properties along its length comprising applying to the spun, solidified, undrawn yarn a plasticiser for the yarn material in an amount varying along the length of the yarn to produce relatively plasticised yarn portions and relatively unplasticised yarn portions and thereafter drawing the yarn to an extent such that variable properties are imparted along its length.
• the present invention relates to a process for producing continuous filament synthetic yarns having properties varying along the length thereof. It relates particularly but not exclusively to such yarns when made from nylon.
• variable yarns Many methods have been described in the patent literature and elsewhere for the preparation of continuous filament yarns having properties, such as thickness or dyeafiinity, which vary along the length of the yarn and which yarns are used for producing fabrics of novel and pleasing appearance. Such yarns, for convenience, will be hereinafter called variable yarns.
• the methods described include pulsating extrusion of the molten polymer at the spinning stage, variable cooling of the melt spun yarn, plucking of the yarn while it is being drawn, drawing in a nonuniform manner and the like.
• variable yarns When such variable yarns are made into fabric and the fabric dyed, the portions with varying properties have different appearances, for instance they exhibit varying degress of lightness and darkness, and when these effects are properly exploited such fabrics can be very pleasing.
• variable yarns as hereinbefore defined wherein a yarn plasticiser is applied to a continuous undrawn yarn made from synthetic polymer in an amount varying along the length thereof and said yarn is subsequently drawn.
• the present invention further provides a process for the production of variable yarns as hereinbefore defined wherein a yarn plasticiser is applied to a continuous undrawn yarn made from synthetic polymer in an amount varying along the length thereof in a programmed manner and said yarn is subsequently drawn.
• Continuous drawing is usually carried out by feeding the undrawn yarn from a feed roll, across a space known as the drawing zone, and onto a draw roll having a greater peripheral speed than that of the feed roll. If in the drawing zone there are portions of yarn some with a relatively ice high water content and some with a relatively low water content then those with a higher water content will draw easily and quickly, leaving those with a lower water content relatively undrawn. Such relatively undrawn portions will hereinafter be termed nubs.
• the length of the drawing zone has an effect on the variation produced and it must be long enough, for a given yarn drawing speed, for differential drawing to take place to the required degree.
• the natural draw ratio of the spun yarn is Another factor of importance.
• the meaning of the term natural draw ratio is well known in the art and may be defined as the ratio of the cross sectional areas before and after a neck formed in the yarn when said yarn is drawn at a mechanical draw ratio at or below said natural draw ratio.
• the yarn should be drawn below the natural draw ratio, preferably at a ratio of around half the natural draw ratio.
• a high natural draw ratio can be obtained by using a low spinning speed or by the use of suitable nucle ating agents. It is known to draw below the natural draw ratio to obtain variable yarn.
• the positions where successive necks are formed in the drawing Zone are determined substantially by the positions where the plasticiser is applied.
• the plasticiser used is water, then should the undrawn yarn be allowed to remain in contact with an atmosphere of a fixed relative humidity there will be a tendency for all parts of the yarn to reach the same, equilibrium water content. For this reason the yarn must be drawn as soon as possible after the variable application of water has been performed. Conveniently drawing may follow immediately and continuously after spinning, in a so-called spin-draw process. This precaution is not so necessary, of course, if a non-volatile plasticiser is used. However, even a non-volatile plasticiser may tend to spread along the yarn instead of remaining in patches and so in this case also drawing should be carried out as soon as possible after application of the plasticiser. Such a non-volatile plasticiser could be, for instance a non-volatile hydroxy-compound such as glycerol, and could be applied in admixture in a suitable medium.
• Such a mixture may contain plasticiser-fixing agents such as thickeners, high surface tension producing agents, or other agents which will bond physically or chemically with the yarn and the plasticiser in such a way as to restrain this latter from spreading along the yarn.
• plasticiser-fixing agents such as thickeners, high surface tension producing agents, or other agents which will bond physically or chemically with the yarn and the plasticiser in such a way as to restrain this latter from spreading along the yarn.
• a preferred method is to apply varying amounts of spinning finish (an aqueous emulsion of oily ingredients) at the spinning stage instead of endeavouring, as is the usual practice, to apply the finish evenly.
• the usual way of applying such finish is to pass the yarn as it is spun continuously over a rotating roll the peripheral surface of which is continuously wetted with the finish by having one part of the roll dipping into a bath of the said finish.
• the yarn is made to contact an arc of the periphery of the said wetted roll by being guided thereon by guide pins.
• the length of arcuate contact between the yarn and the rotating roll can be varied and such movement of the pin may be of such extent as to remove the yarn from the said roll. In this way the amount of finish applied to the yarn can be varied along the length of the yarn.
• the length of contact between yarn and roll can be varied in such a way as to obtain a desired pattern of water content along the yarn.
• spinning finish can be applied uniformly and a plasticiser applied non-uniformly previously or subsequently to such finish application.
• Another method is to wind undrawn yarn having a relatively uniform water content to form a package, using varying traverse length.
• the package is allowed to remain in an atmosphere wherein the equilibrium water content of the yarn is different from its actual water content.
• the yarn at or near the exposed edges will thus acquire a water content different from that of the rest of the yarn.
• the undrawn yarn may be passed, at any stage prior to drawing, through a suitable means for applying a plasticiser such as water, alone or in admixture with other agents, for example dyeing modifiers which alter the rate of dye-absorption or the colour produced by the dyeing process, in an amount varying along the length of the yarn.
• a plasticiser such as water
• other agents for example dyeing modifiers which alter the rate of dye-absorption or the colour produced by the dyeing process, in an amount varying along the length of the yarn.
• variable plasticiser content such as varying the movement of a guide pin, varying the applicator roll speed, varying ejection of the plasticiser from a jet, varying traverse stroke and the like may be performed using any of the many already Well known means.
• suitable electronic and mechanical equipment programmes of almost any complexity may be devised, such as short repeat patterns, long repeat patterns, pseudo-random patterns and the like.
• Average nub peak denier 1.3 to 4 times the denior of the drawn sections.
• a particularly preferred yarn has nub parameters as follows:
• a very convenient programming method is to use the signals from a pseudo-random signal generator to control the operation of the plasticiser applicator.
• the present invention is general in nature and may be operated with many types of synthetic polymer yarns, such as polyethylene terephthalate, using suitable plasticisers applied in a varying manner to the yarn before said yarn is drawn.
• the effects obtained using the present invention can be combined with other effects, for instance the yarn may be bulked or crimped by known methods, either during the drawing operation or at any other suitable stage in yarn manufacture.
• Example 1 A nominally 1040 denier 68 filament yarn was spun and drawn in one continuous operation (spin-draw) under the following conditions:
• the finish was applied to the spun yarn using a conventional finish roll technique.
• An upper cross-pin, guiding the yarn to make arcuate contact with the roll, was made displaceable in such a manner that such displacement caused the length of arcuate contact between the yarn and roll to vary approximately between 0 and inch at an average frequency of about 10 times per second.
• the displacement of the said pin was controlled according to a pseudo-random programme initiated by a pseudo-random signal generator.
• nub positions corresponded substantially with those predicted by the programme.
• the yarn was then down-twisted to 0.6 t.p.i. and incorporated in the weft of a woven fabric.
• Example 2 A nomintl 1040/ 68 gear-bulked yarn was produced under the following conditions, in a spin-draw-bulk process, with finish applied as in Example 1.
• Polymer 6.6 nylon with 0.03% TiO Spun denier 2618,
• Wind-up speed 2000 f.p.m.
• the yarn was drawn over a hot snubber pin at C. before enter the gear intermeshes.
• the gears had 20 teeth/ in. and a 27,000 intermesh.
• This yarn after down-twisting to 0.3 t.p.i., was incorporated in the Warp of a woven fabric with a production bulked nominal 1040/ 68 yarn in the weft. This was dyed with a rate sensitive golden yellow premetalized dyestuff which gave an aesthetically pleasing pale yellow fabric with dark orange streaks in the warp direction, with a pleasant handle, considerably less crisp than that of the fabric of the first example. No signs of periodicity were observed in the fabric.
• Example 3 A nominally 1040/68 gear-bulked yarn was produced by a split process.
• Example 2 the yarn was spun-drawn, with programmed finish application, and wound up onto a support, in this case a bobbin. This yarn was then further drawn through gears to give a bulked product as in Example 2. We confirmed that the programme was being transferred to the yarn by means of continuous denier testing apparatus and that the nubs were still present after draw-bulking by means of a Fielden Walker tester.
• Wind-up speed 2000 f.p.m.
• the yarn from this step was gear draw-bulked by the following process:
• the resulting yarn was incorporated in a weft knitted construction and dyed blue with a rate sensitive acid dyestuif. A panel with dark blue patches on a light blue ground resulted.
• Example 4 A nominal 1040/68 flat yarn was produced under the following conditions, by the split process, using pseudorandom programmed finish application.
• the spun yarn was then further drawn to a ratio of 1.35 and twisted to 0.6 t.p.i. This was incorporated into a weft knitted fabric and dyed in the same dyebath as fabric from the yarn of Example 3, in a rate sensitive blue acid dyestulf.
• the nub parameters were as in Example 3.
• the resulting fabric presented a light blue ground with darker blue patches, of lower overall contrast than material produced from the yarn of Example 3, giving a more subtle effect. 4
• Example 5 A thick-thin yarn, having dye resist portions along its length, was produced by exactly the same processes as in Example 4 except that to an aqueous finish containing 10% v./v. oil there was added 8% w./v. of Lissotan PR (a trade name).
• the yarn so produced was weft knitted into panels, as were yarns produced by the process of Example 3. Compared with the latter, considerably greater colour contrast between the nubs and background was obtained when the yarn was dyed in a rate sensitive blue dyestuif.
• An interesting two tone effect was achieved by dyeing a knitted panel of this yarn in a single dyebath containing a non-rate-sensitive blue acid dyestuff and a similar golden basic dyestuif.
• Example 6 A nominal 205/34 bulked thick-thin yarn was produced by a split process under the following condition:
• Polymer Nylon 6.6 containing 0.3% TiO R.V. -35
• Wind-up speed 2000 f.p.m.
• Length of draw zone 72 ins.--no snubbing pin.
• the resulting yarn was further draw-bulked to a draw ratio of 1.25 at a drawing speed of 1295 f.p.m.
• Example 7 Example 1 was repeated, but this time with a strictly periodic programme.
• the nub parameters corresponded closely with the programme, namely: spacing approximately 25 ins., length approximately 98 ins. peak denier approximately 2 to 2.5 times the denier of the drawn sections.
• Example 8 Yarn was spun and drawn in one continuous operation (spin-draw) under the following conditions:
• Snubbing pin-2 ins. diameter and heated to 100 C.
• the finish was applied to the spun yarn using a conventional finish roll technique.
• An upper cross-pin, guiding the yarn to make arcurate contact with the roll, was made displaceable in such a manner that such displacement caused the length of arcuate contact between the yarn and roll to very approximately between 0 and inches at an average frequency of about 10 times per second.
• the displacement of the said pin was controlled according to a pseudo-random programme initiated by a pseudo-random signal generator.
• a process for the production of a spun continuous filament synthetic yarn having variable properties along its length comprising applying to the spun, solidified, undrawn yarn a plasticiser for the yarn material in an amount varying along the length of the yarn to produce relatively plasticised yarn portions and relatively unplasticised yarn portions and thereafter drawing the yarn to an extent such that variable properties are imparted along its length.
• a process as in claim 1 including winding up the yarn between the step of applying the plasticiser and the drawing step.
• a process as in claim 1 including continuously forwarding the yarn through a zone where the plasticiser is applied by contacting the yarn with a source of the plasticiser and wherein the contacting step includes moving the yarn to vary the contact of the yarn with the source to thereby eifect the variations of plasticiser along the length of the yarn.
• a process as in claim 5 including the steps of generating signals and moving said yarn path in accordance with said signals.

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• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Mechanical Engineering (AREA)
• Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)
• Artificial Filaments (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=10472833

Family Applications (1)

Country Status (5)

Cited By (3)

• 1966
  • 1966-12-08 GB GB55062/66A patent/GB1150638A/en not_active Expired
• 1967
  • 1967-11-22 US US684954A patent/US3591672A/en not_active Expired - Lifetime
  • 1967-12-04 NL NL6716461A patent/NL6716461A/xx unknown
  • 1967-12-07 BE BE707692D patent/BE707692A/xx unknown
  • 1967-12-08 FR FR131628A patent/FR1547941A/fr not_active Expired

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