US2155519A - Textile yarn and fabric and method of making same - Google Patents

Description

Patented Apr. 25, 1939 UNITED STATES TEXTILE YARN AND FABRIC AND METHOD OF MAKING SAME William Whitehead, Cumberland, Md., assignor to Celanese Corporation of America, a corporation of Delaware No Drawing. Application July 18, 1936, Serial No. 91,423

8 Claims.

This invention relates to the production of a yarn formed from artificial materials which has a varying denier and is twisted more in those parts having the smaller denier. This invention also relates to fabrics formed from such yarns.

An object of the invention is the production of yarns from artificial filaments which, when formed into fabrics, produce fabrics having distinct characteristics and the production of such 10 fabrics. Another object of the invention is the production of yarns from artificial filaments which, when formed into fabrics, produce seersucker and/o'r crepe eflects depending upon the weave. Other objects of the invention will ap- 16 pear from the following detailed description.

The yarns to be employed in producing the yarns or threads of this invention are yarns of substantially continuous filaments made of or containing an organic derivative of cellulose,

20 which yarns have a regular or an irregular varia-' tion in denier. The variation in denier may be produced by drawing the yarns at varying linear speed in the course of their production so as to stretch them at any desired intervals. The vary- 26 ing stretch imparted to the filaments or threads results in a correspondingly varying denier; the variations may occur at any desired intervals and to any desired degree while extending any desired distances along the length of the fila- 80 ments, yarns or threads. This may be accomplished by a device which draws the filaments at varying linear speeds by periodically lengthening the path followed by the filaments, in the course of their production, to a winding, or twisting and winding device. As instances of the methods by which the yarns may be produced, reference is made to U. S. Patents Nos. 1,996,796 and 1,898,085.. Other methods may be employed in forming the yarn of substantially continuous 46 filaments having a variation in denier.

It will be understood that where yarn or thread is formed by the association of a number of filaments all of which have a regular or an irregular change in denier'which change is similar for all the filaments at a cross-section of the yarn, there will be a cumulative eflect in change of denier of the yarn at that cross-section.

In accordance with my invention, I produce yarns or threads of substantially continuous filaments having avarying denier and having a varying degree of twist with the highest degree of twist at the sections having the smaller denier. Where the degree of twist is relatively high, the twist or at least apart of the twist is inserted in theyarn while the yarn is under the influence of steam. It is of great advantage to have moisture present in those twisting operations employing steam.

Yarns or threads with irregular denier having a substantial twist, for instance, of 3 to 80 or more turns per inch in the portions of smaller denier, impart a novel effect to fabrics or articles wholly or partially formed from them by reason of the differential effect produced by the variation in the amount of twist and the corresponding compactness of the yarns or threads in the various intervals along their length. The differential effect is enhanced when the fabrics or articles are dyed, printed or otherwise colored because of the differential of penetration in the dyestuif or other coloring matter and of the differential in luster between tightly twisted small denier intervals and the intervals of large denier with little or no twist.

The yarns or threads of varying denier and twist may be applied to the production of fabrics or articles either. alone or in association with yarns or threads of uniform denier artificial silk or other natural or other artificial filaments or fibers and may be utilized to give any desired design or pattern. They may be used, for example, in the warp and/or weft in weaving operations, in knitting operations, for instance, in the production of warp knitted fabrics, in circular knitting machines, in braiding or cording operations, in net or lace-making operations or in any other fabric-forming or textile operations. For instance, a fabric having novel effect may be formed by employing as a warp uniform,

denier yarn and a filling of irregular 120 denier having a twist of from 50 to or more turns per inch in the portions having the smaller denier.

A seersucker effect is produced only with warps of a low number of ends, say to ends per inch with 60 to 80 picks per inch. Warps having 130 to 200 ends per inch do not produce a definite seersucker effect but a crepe effect. The crepe effect is distinctive in that the variation in denier and twist produces an uneven creping property along the length of the yarn.

While the invention relates particularly to filaments or threads of varying'or irregular denier and twist, produced by the dry or evaporative method, and especially to filaments'or threads having a base of cellulose acetate or cellulose derivatives, such as cellulose formate, cellulose propionate or, cellulose butyrate, thiocarbamic acid alkoxy-alkacyl esters of cellulose, methyl, ethyl and benzyl cellulose, the condensation products of cellulose and glycols and other polyhydrie alcohols, it applies likewise to filaments or yarns of varying denier and twist produced by the wet or coagulation method, whether it has a base of cellulose or bases of reconstituted cellulose produced by the viscose, cuprammonium or nitrate processes.

If desired, the filaments of the yarns or threads may contain water insoluble compounds such as compounds of pigment-like character in such form as materially to modify the luster of the filaments (e. g. barium sulphate or titanium dioxide), or loading metal compounds, forexample, tin compounds.

The twisting operation may be performed on any suitable type of device; however, where the yarn is to be twisted to more than 8 turns per inch, it is preferable to twist the yarn in the presence, or while it is under the influence of steam. This is especially true where crepe yarns or threads are being formed which have from 50 or more turns per inch in the tightly twisted portions. Regardless of the type of twisting device employed, those portions of the yarn having the smaller denier will take the twist while those portions having the larger denier will take little or no twist depending upon the relative thickness of the slubs forming the thick places. The proportionate amount of twist in the yarn at any particular point will be nearly inversely proportional to the square root of the denier in those twisting operations that do not employ steam. Applying steam to the yarn effects the thick parts of the filaments differently from the thin parts of the filaments, allowing the twist as it is inserted to run to the thin places, leaving the thick places with comparatively little twist.

By employing this invention, yarns may be formed that are highly twisted and compact at certain sections which are separated by sections that are relatively free of twist. When employing a bright yarn (e. g. unpigmented or not delustered), and when such yarns are woven into a fabric, the untwisted sections of the yarn are much the brighter, producing a glittery mark or line in the fabric. When pigmented yarns are employed, there is produced no glittery effect by the untwisted slubs or thick places. In carrying out the new process for the production of highly twisted threads, the twisting may be effected on the device of the kind on which a thread is drawn off over the end of a rotating package through a guide fixed preferably substantially in line with the axis of rotation of the package and is thereafter wound on a bobbin or the like,

, the thread being passed--on its way from the guide to the bobbinthrough steam. In this way the thread is subjected to the action of the steam during the actual application of a substantial amount vof the twist, or to the action of both steam and moisture if it is passed through the steam under such conditions that moisture is present.

yon-the other-hand, any other suitable-c7fepe twisting device may be employed in conjunction .with steam. "Foremmple, a ring twister or other suitable devicesmay be used for the crepe twisting of the thread. As examples of such devices may be mentioned flyers and floating ring devices. described in-British Patent 304,806 of the British Celanese Limited and others.

Steaminglmay conveniently be effected by allowing the threadfto pass through a suitable chamber'suppliedfwith steam preferably under such conditions that moisture is present. The.

chamber is provided with small holes, top and plied 'to' the yarn suniig When twisting yarns int-he presence of steam,

bottom, to permit passage of the thread, and also with a steam inlet. If desired, a single steam chamber may be arranged to serve a number of twisting devices, being provided with inlet and outlet holes for the thread of each device. Such an apparatus may conveniently consist of a horizontal pipe mounted over a row of twisting devices and provided with eyes of porcelain, stainless steel, or other suitable materials at appropriate points on top and bottom for the entrance and exit of the threads. The diameter of the pipe may be suflicient to afford the thread the requisite length of travel in the steam. Alternatively, a pipe having a smaller diameter may be used, in which case the pipe may'be provided with hollow nipples communicating therewith and through which the yarn passes, the nipples being of sufficient length to provide-together with the diameter of the pipethe requisite length of travel in the steam.

The presence of the desired moisture may be assured by supplying wet steam to the steaming device and/or by arranging for the condensation of steam to supply the requisite amount of moisture. I Wet steam may be conveniently produced by passing steam through water at a suitable velocity for instance, small traps for condensed water may be provided at suitable intervals in the steaming chamber and steam injected therethrough by means of small pipes or-- orifices. Another method of ensuring the presence of moisture is to wet the thread with water. For example, the bobbins of the thread may be wetted before the twisting operation or, better, water may be applied to the thread by means of a wick or other device after the thread leaves the spindle and prior to its entering the steaming device.

Steam at slightly above atmospheric pressure, or at a pressure of l to 2 millimeters of water, is most conveniently employed. If desired, how- 7 ever, the steaming may be effected with steam at any desired superatmospheric pressures, e. g. steam at 10-25 lbs. per square inch.

A steaming treatment of relatively short duration such as may be secured by passing the yarn at a speed of from 2 to 10 metres per minute through say from 1 to 6 inches of steam has been found to givesatisfactory results. Lengthier treatments, may however be employed, for example the yarn may be passed at the said speeds through 6 to 12 inches or more of steam.

The degree of twist applied in accordancewith this invention may vary within wide limits. For instance, in the production of yarns for voiles, ninons and like fabrics, a twist of from to turns per inch in the portions having the smallest denier may be suflicient. In this type of yarn, although steam may be employed, it is not necessary to steam the yarns while twisting the same. As another instance in the production of threads or yarns to be woven into taffetas and like fabrics, a twist of from 3 to 10 turns per inch may be placed in the portion of yarn having the smaller denier. In some fancy fabrics, a twist of from 15 to 50 turns per inch may be employed, while inseersucker and crepe fabricsga twist of from to 100 or more-turns perfin'ch may be inserted in the portionshavin'g the smaller denier. In twisting the yarn-to above 20 turns per inch it is preferable but not necessary that steam be ap. sting operation.

of substantiallycontinuousfilaments containing cellulose-acetate; may be produced a yarn having from to'80,ior more turns per inch in said yarns in the presence of moisture, and.

one section and from tom turns per inch in other sections. For instance, with a ratio of 1 to 6 denier change the smaller denier sections will twist to about '75 turns per inch while the slubs will hardly be twisted at all. It is to be understood that the ratio in denier variation need not be the same in the yarns before and after twisting.

A feature of the process which employs steam is that it enables a very high degree 01' twist to be applied to the low denier portions of the yarn without such a great weakening of the thread as is invariably experienced when such threads are prepared without steam. This is important since it enables crepe fabrics having very pronounced crepe efl'e'cts to be produced. The crepe figure can be regulated according to requirements. The degree of twist desirable in any particular case depends upon a number of factors including the precise efi'ect required, the denier, the number of filaments in the thread, etc.

It is .to be understood that the'i'oregoing detailed description is given merely by way oi! illustration and that many variations may be made therein without departing from the spirit of my invention.

Having described my invention, what I desire to secure by Letters Patent is: v

1. Process for producing crepe yarns which comprises forming yarns having a varying denier from an organic derivative of cellulose, twisting the yarns while the yarns are under the influence oi steam, whereby the ratio of the degree of twist inserted in the thin portion of the yarns to the degree of twist inserted in the thick portion of the yarns is greater than the inverse ratio oi the square roots of the deniers of said portions.

2. Process for producing crepe yarns which comprises forming yamshaving a varying denier from cellulose acetate, twisting the yarns while the yarns are under the influence of steam, whereby the ratio of the degree of twist inserted in the thin portion or the yams to the degree of twist inserted in the thick portion or the yarns is greater than the inverse ratiooi' the square roots of the deniers of said portions.

3. Process for producing crepe yarns, which comprises forming yarns having a varying denier from an organic derivative of cellulose, steaming twisting said yarns while said yarns are under the influence oi the steam and moisture, whereby the ratio of the degree of twist inserted in the thin portion of the yarns to the degree oftwist inserted in the thick portion of the yarns is.

greater than the inverse ratio of the square roots of the deniers of said portions.

4. Process for producing crepe yarns, which comprises forming yarns having a varying denier from cellulose acetate, steaming said yarns in the presence or moisture, and twisting said yarns while said yarns are under the influence oi the steam and moisture, whereby the ratio of the degree of twist inserted in the thin portion of the yarns to the degree of twist inserted in the thick portion of the yarns is greater than the inverse ratio of thesquare roots of the deniers 01' said portions.

5. Crepe yarns or filaments containing an organic derivative of cellulose, which yarns have a varying denier and a varying degree of twist, the ratio of the degree oi! twist in a thin portion of the yarn to the degree of twist in a thick portion of the yarn being greater than the inverse ratio of the square roots of the deniers oi. said portions.

8. Crepe yarns or filaments containing cellulose acetate, whichyarns have a varying denier and a varying degree of twist, the ratio or the degree of twist in a thin portion of the yarn to the degree of twist in a thick portion of the yarn being greater than the inverse ratio of the square roots oi the deniers of said portions;

7. Crep yarns or filaments containing an organic derivative of cellulose, which yarns have a varying denier in which the ratio oi; the smaller denier to the larger denier is 1 to 6, and a twist of more than 50 turns per inch in the portions 01' smaller denier and a twist of less than 20 turns per inch in the portions of larger denier.

8. Crepe yarns or filaments containing cellulose acetate, which yarns have a varying denier in which the ratio 01' the smaller denier to the larger denier is 1 to 6, and a twist of more than 50 turns per inch in the portions of smaller' denier and a twist of less than 20 turns per inch in the p rtions 01' larger denier.