IL29962A - Method of stabilizing bulked continuous filament thermoplastic yarn - Google Patents

Description

Method of Stabilising Bulked Continuous Filament Thermoplastic Yarn This invention relates to the production textured from or bulked formed highly continuous yarns and more particularly to a method of stabilizin such yarns with heat to obtai a uniform bulk level Textured continuous filament yarns are now extensively used in the textile industry at in to their outstandin covering texture and easy care and long wear Many different processes nave been developed for urizing the raw continuous filament thermoplastic but all of such processes generally involve a combination of an distorting the for such yarns can be textured by being passed or by being overfed and stu e heating chamber or by a combination of setting and such as a twist operation wherein the yarn is and untwisted in one continuous In those processes involvin twisting and setting to bulk the the quite lively or and highly stretchable after it to modify or stabilize the yarn at the desired bulk level by subjecting it to an additional The with which continuous filamont thermoplastic yarns can be textured or bulked by twisting is more than offset b the roblems encountered in stabilisin the yarn and yarn package to yarn since the unstahilised yarn is lively and highly stretchable and it is difficult to a quantity of such yarn at a given level for length of sufficient to stabilize the yam shrinks to varying degrees during have envolved in art for these highly stretchable lively bulk Fo where uni ormity of bulk level is not too it common merely to a package of such yarn with the havin been overfed onto the package to an extent sufficient to create a theoretical Although this method is highly desirable from standpoint of expediency and since it involves a of it has not heretofore resulted in obtaining a uniform bulk level throughout the This is due to the fact that the which has a strong tendency to contract due to its highly stretchable begins to contract therefore after it is wound into package and while the outer portion of the can so contract a calculatable amount inwardly of the the yarn in the inner portion of the package does not have the same amount of freedom due to the presence of the winding As a result of after stabilization even of such the yarn in the portion of the package will have a lower bulk level than the yarn in the outer often as m c a 8 to o e e Another method involves winding tho zed yarn onto a bobbin vithout overfeeding thus vithout and then removing the whereupon the yarn is then wholly free to contract inwardly toward the center o the package and bulk to a given thus bulked yarn is the stabilized at such bulk A considerable drawback to this is all of the bulk be developed after the yarn is wound into package and uniformity and control of bulk level within packages and from package to package is difficult to Still other methods involve rewinding of the package into another more suitable form for such as a but of rewinding naturally adds considerably to tho cost of tho In accordance with the present X have discovered a new method of stabilizing bulked continuous yarns by which an exceptionally high degree of bulk uniformity can be maintained with a minimum of winding or handling this new method involves the of a package of highly atretchable yarn wherein bulk of the yarn the outer portionof the package is at substantially the bulk level by replacing the winding core thereof with a of a predetermined smaller diameter to permit the of the yarn in the inner portion of the package to increase to the desired level of the other yarn and give such yarn more room to shrink during The thusly modified package is then compressed to the yarn and obtain mote uniform it is by forcing a heated through the as for by it in a yarn package dyeing of the objects of the invention having been othe will appear the description whe taken in connection with accompanying in Figure 1 is a schematic illustration of a yarn twisting Figure 2 is an view of an apparatus suitable for replacing and inserting cores of and into yarn packages and for such Figure 3 is a fragmentary side elevation of core replacing elements and comprising the apparatus shown in Figure Figure 4 is similar to 3 and additionally shows a yarn package positioned for replacement of its 5 is a still further enlarged fragmentary vertical sectional view of a yarn package as in Figure 4 during replacemen of the winding core and Figure is similar to Figure 4 and shows the yarn package after replacement of core during Be now more specifically to the and particularly Figure there is represented a schematic illustration of a conventional operation for bulkin a continuous lastic arn such In the a yarn is typically bulked by being led supply package through suitable holding heating a another holding means and onto a package wound on a core as a cardboard As is veil known in the the foregoing arrangement produces a highly yarn by continuously and then In producing bulk yarns by this it is common to overfeed the yarn om the holding means 14 onto the package This overfeeding together with the tendency of the yarn to contract to its highly stretchable causes the yarn to bulk and this can be controlled to produce a desired bulk As stated the bulk level of the yarn within such a tends to vary as much as 8 to from the inside to the outside of the package due to the fact that the yarn in the inner portion of package is prevented contracting by the winding core In view of the in accordance with the present package 15 of such yarn is formed so that the bulk level of the yarn on outer portion is at that level which is ultimately and the bulk level of the yarn in the inner portion of package is below such Due to the delicate nature of some continuous filament it is often desirable to cover the yarn package 15 with a sock 17 or the as shown in the Such sock usually takes the form of a knitted which covers and is stored vith the winding core 16 before winding and which has sufficient length and stretchability to fit around the package after In modifying the thus package the core replacing operation should be by simultaneously inserting the perforate core while removing the winding as by pushing one with the the package 15 will close inwardly too much and the bulk level of the yarn toward center of the package will increase to a level greater that of the yarn toward the By the it is necessary that the perforate replacement core bo of a just enough smaller than the diameter of the winding core 16 to permit just enough inward expansion of the package to achieve the desired uniform bulk This difference diameter will vary with different types and of thermoplastic For in the case of polyester yarns in the range of 70 to 200 the difference in diameters should be within the range of about to The replacement core is such as a foraminous stainless steel dye tube or dye in order to permit free flow of therethrough and through the package during the stabilising For removing winding core 16 from the package I provide an apparatus such as that shown in Figures which comprises a vertically movable mandrel 20 operable o a i o i lind 2 t bov A flange 22 is provided on the upper end of the for reasons which will become apparent A platform 23 is provided below the mandrel 20 for supporting a yarn package to such platform having an opening 24 there in to permit of the expelled winding core 16 through the platform and a collection point As the package 15 is centered on the platform 23 so the core positioned directly over the opening A tube 25 is placed on the mandrel upon actuation of the air cylinder the perforate tube 25 is engaged by the flange 22 pushed downwardly into engagement with tube whereupon continued downward movement causes the tube 25 to push the tube 16 completely out of the In winding yarn into it is almost impossible to obtain uniformity of yarn density throughout the package primarily to the tendency of the yarn to buildup hard spots at the end of the traverse at the top of the the compression or up of the modified package is also in the present method in that it tends to break up any hard spots in the package and achieve a more uniform density To this a compressing of the package may be carried out during the core replacement operation as for in Figure 6 wherein continued downward movement of the mandrel 20 after insertion of the tube 25 brings the flange 22 into axial compressing After replacing the core 16 the core 25 and compressing the package as heretofore the thusly modified baa a uniform bulk level throughout and is in condition for In stabilising 1 have that a considerably more uni bulk level can be maintained by that setting with a liquid such as rather than the This of highly desirable since it use of conventional yarn package dyein machinery rather than an autoclave for stabilising the yarn and further one to stabilize during a conventional dyeing Some of the complete process are as Example A continuous filament polyester yarn is bulked on a f wist machine by inserting 56 turns per inch through the heating zone with the heate block being maintained at with the being overfed in the heating to ov for and the package being run at a speed slower than the yarn supply speed to allov the yarn to a predetermined Δ package of bulked yarn is thus formed weighing approximatel lbs and being supported on a paper tube having an outside diameter of inches inches and inch package is placed in any suitable apparatus where the tube or core is pushed out with and replaced diameter of inches inches and inch and the package is then compressed by applying axial force The thus compressed and modified now has a uniform bulk level placed along with other similar packages in a package dyeing where the yarn is then stabilized by pumping water at 250 through the packages for 30 40 The yarn packages are then extracted and dried in a conventional A 150 denier continuous polyester yarn is bulked in a similar to that described in Example 1 that 60 turns per inch of twist and onto the are In this the yarn is taken tube having an outside diameter Of inches inches and inch wall The package is then modified in the same way as in Example 1 by replacing core with a stainless steel perforate dye tube having an outside diameter of inches inches and inch wall and compressed by applying an axial compressive force The package is then placed along with other similar packages in a yarn package dyeing machine and dyed with the temperature of the being held at 250 for at least 30 The dyed and stabilized yarn packages are then extracted and driod in a insufficientOCRQuality

Claims (1)

Claims A method of stabilising a core supported wound package of highly continuous in thermoplastic the bulk of the in the outer portion o the package is at substantially a desired bulk level and the of the wound yarn in the inner portion of the package is below such desired bulk comprising the of the bulk level of the yarn in the inner portion of package while maintaining substantially constant the bulk lovel o the yarn in the outer portion of the package by removing the package core while Inserting in lieu smaller thereof a perforate core of a to obtain a uniform bulk level throughout the uniform axially compressing the package to obtain a then the package with a liquid to stabilise the entire of yarn at substantially said A method according to wherein the package is treated with a containing aqueous bath to dye the yarn while stabilizing the A method according to

1. Claim 1 or 2 wherein the yarn is a polyester yarn in which the bulk high strotchability has been thereto by and untwisting in a continuous A method according to any of Claims 1 to 3 wherein the package is ith an aqueous bath at for least 30 A method of stabilizing a core supported vound package of highly continuous thermoplastic substantially hereinbefore described vith reference to the accompanying and to ts insufficientOCRQuality