[1]Patented Nov. 1.6, 1937- 29098998-1 UNITED STATES PATENT OFFICE 21099,981 YARN YIANWACTURE Percy Frederick Combe So@@r, Spondon, near Derby, England, assignor to Celanese Corporation of America, a corporation of Delaware No Drawing. AppReation January 26, 1934, Serial No. 708,405. In Great Britain Feb. 15, 1933 is Claims. This inventit)n relates to the manufacture of Yarns, particularly yams having a basis of fegenerated cellwose, having the appearance of spun yarn or yam made of staple fibre, and also relates to fabrics made therefrom, and is a continuation in part of U. S. application S. No. 651,847 filed 14th January,41933. 7be parent specification describes a process for the manufacture of artificial spim yam, partle10 Warly from materi6ls containing ceuulose aceItate or other organic derivatives of cellulose, In which a bundle of Maments In a softened state Is ..subjected to an operation such that individual ,filaments are broken while the continuity of the niain fhament bundle is maintained. As Is described therein, a particularly valuable method' of carrying out the iiivention comprises subjectIng the fllament bundle in a softened @tate to a stretch which Is greater than Individual fila20 ments are capable of supporting, but is not sufficient to break the filament bundle as a whole. 3:n this manner a yam baving a numbei of broken ends may be obtained which resembles yam obtwned by the spinning of staple fibre. 25 It has now been discovered that the invention is also of value in the production of Imitation spun Yarn containing materials having a basis of regenerated izellulose, such as are obtained, for example, by the viscose, cuprammonium and ni3.0 trocellulose processes. According to the present invention, therefore, an imi,tationspun-yam havIng a basis of regenerated cellwose Is obtained by subjecting a bimdle of filaments in a softened state to an operation, and preferably to a stretch35 ing operation, such that individual fdaments are broken, while the continuity of the main filainent bundle is maintained Breakage of the Individual filaments may be effected at any sultable stage in the manufacture 40 of the imitation spun yarn, either during or c . ontinuously with the spinning operation or as a subsequent step separate from the production .of the artificial Maments. Thus in the cuprammonium process the fflaments may be subjected 45 to a stretch which is greater than individual fflaments are able to withstand at any stage of their production, e. g. In the &A bath in which stretching is mainly effected in the usual stretch spinning process, the m6tion of the Uqidd assist50 Ing In carrying on the broken fuaments, or In the subsequent precii)ita;ting bath. Siniflarly in the production of artificial materials by the viscose ,process the speed of rote@tion of the draw-roller may be such that the materials In the coagulat55 Ing bath itself are subjected to a stretch which (CL 19-1) effects a breakage of the individual f)lament's without causing ruptlire of the bundle as a whole, or the bundle of Maments after emerging from the coagulating bath may pass round two or more lap rollers or between two or more pairs of nip 5 rouers, the relative speeds of rotation of which are adjusted so as to bring about the desired rupture. of Individual filaments. Treatment of the Mament bundle to effect breakage subsequent to its emergence from the coagulating bath 10 may be carried out either in a further bath or In the absence of such bath. When it Is desired to effect the breakage of the fuaments In the coagulating bath itself, it Is preferable, to employ some means of preventing or restricting the 15 stretch applied by the stretching roller from extending back to the jet, for example by passing the bundle of filaments round or over guides or rollers or by employing a coagulating bath flowIng In a counter-current to the direction of travel 2(j Qf the fgament bundle. When the materials are produced by dry spinning processes, as for example In the case of artifleial silk obtained by the nitrocellulo se process, the breakage Is preferably effected subsequent to the actual production of 20 the filaments, either continuously with their production, e. g. by passing them round two rollers, the second of which. rotates at such peripheral speed as to break individual filaments, or in an operation separate from that of their production. 30 The breaking operation may be effected on the formed fflaments, either before or after, or even during denitration. 'Me imitation spun yarns of the present invention may ajso be obtained from materials 35 containing organic derivatives of cellulose, e. g. by saponilleation of the yams produced according to the process of the parent specification, or by saponifying normal cellulose ester filaments and the Uke and subjecting them to an operation to 40 cause breakage of individual filaments, either 'during or subsequent to saponification. While partiewar examples of fiiethods of effecting, breakage of Individual fllaments have been described above, it win be appreciated that 45 the present Invention contemplates broadly the manufactu re of Imitation spun yains containing regenerate d celaulose by causing breakage of Individual filaments at any stage In the productioil of the materials, whether prior to, during or sub- 50 sequent to regeneration of the celliflose, As stated above, the operation to effect breakage of @ the Individual filaments may, ff desired, be carried out as a process separate from the production of the &ruflctal materials. Thus a ym 55
[2]2 in hai@k form may be softened and s'ubjected to a stretching operation or breakage may be effected during,the travel of the materials from one point to another, for example from bobbin to bobbin. Softening of the materials may be effected either prior to oi, duxing the stretching operation, for example by passing a yam through a bath containing'a swtable softening agent or by immersing it in package, hank or other suitable form In 10 the softening agent. Again, a number of yams In warp formation may be subjected to a stretching or other operation whue In e@ softened state in order to effect breakoge of Individual filaments, and, if desired, 15 a number of such yarns nlay then be associated together to form a single yarn of larger denier. The operation to effect breakage of the indivi fuaments may be carried out upon the fuanient bundle either in an untwisted or twiste@ 20 state. Preferably, however, the bundle has a low twist. A flnal twist may be effected after breakage of the individual fuaments and while the yam Is in a softened condition whether or not It has previousiy been twisted. In this man25 ner, a more crinkled yarn may be obtained. If desired, however, the softening agetit may be removed from the yarn, fGr example by washing, before the final. twist, if any, is effected. After breakage of the individual Maments the 30 yarn may be wound or twisted and wound In a I ny suitable manner, e. g. by means of a cap spinning apparatus or a centrifugal spinning box. The degree of softening of the yarn when it is subjected to the operation to effect breakage 35 of the Individual filaments wtH, of course, depend upon the amount of stretch and the rediletion. of denier which it Is desired to obtain In the finished materials, but in geneml It is preferable that the yam should be in such condition that 40 a relatively high degree of stretch e g. 300-400% or more, Is possible before the i;;@@lite number of breakages li obtained. In this manner a yarn may be obtained which may be a&sociated with other yarns to yield a thread of suitable denier 45 having a large number of broken ends per unit length, and futther by effecting a relatively high degree of stretch the tensile strength of the materials may be Increased. Any suitable softening agents for the materials 50 to be treated may be employed, for example sulphuric acid or other mineral acids, caustic alkali and other alkaline reagents, thlocyanates, zinc chloride and other compoimds having i@ softening or swelling aetion upon the materials. The con55 centrations of reagents employed will, of. course, depend upon the degree of stretch it Is desired to obtain, and upon the temperature and duration of application of the softening agents and other factors, but It will be appreciated that in 60 general, with the sailie starting inaterials and when other conditions are the same, a somewhat lower concentmtion will be employed to obtain an Imitation spun yam according to the present invention than would be used to obtain a normal 65 yarn having the same degree of stretch. As Is shown above, however, it Is preferable that the yarn should be softened to such an extent that a high degree of stretch Is obtainable before breakage according to the present invention results, 70 and the use of baths having a high sofwning power, e. g. 50-70% sulphuric acid and equivalent concentrations of other agents, Is therefore particularly @.valuable. Breakage of the filaments resulis in a number r) of JUament ends projecting from the yarn. U considemble hariness of this character is not desired, twisting may serve to bind the ends as far as possible in the yam. If desired, the yam may be treated, as for example by passage between or over brushes or between rollers, so as to lay 5 the ends substantially in the direction of the length of the yarn to facilitate twisting-in of the ends. The yarii may be subjected to a gassing operation to remove superfluous projecting Maments. 10 Alternatively, the yarn may be passed over a roughened surface or edg6 In order to fray out the fhaments and yield a product of Increased halriness, e. g. during the washing or drying of the stretched yarn. Such an operation may it- 15 self bring about breakage of Individual filaments, and.may be carried out In conjunction with the ktretching process, or, though less preferably, instead of such process. The yarns obtained according to the present 20 invention may be subjected to any desired after treatment to improve or modify their properties, e. g. they may be treated to incorporate finely divided materials therein for delustring, mordanting, weighting or other purposes, or may be 25 subjected to shrinking operations to Improve their extension or other properties. As described In the parent specification, to which reference is made broadly, the yams containlng broken Maments may be doubled with 30 other yarns of a similar or dissimilar nature, either with regard to the type of constituent fUaments or fibres, or as regards the substances constituting the Maments or fibres. Thus two or more broken filament yarns may be doubled to- 35 gether to Increase the denier and/or Improve their regularity or for arly other purpose. Further, the yarns employed.for the produbtion of the lmliation spun yarn or for. doubling with such yarn may be of 1-dgh, medium or low lustre, and 40 the association of different types of yams may take place before or after breakage of the condjtuent Illaments. The yarns or mixed yarns of the Invention may be employed in the production of woven, 45 knitted or other fabrics and may constitute either the whole or a portion of such fabrics, for example a fabric may be woven r-ontaining a warp of normal yam and a weft of the imitation spun yam obtained according to the present inven- 50 tion, or again the warp or weft may be constituted of a normal or imitation spun yarn of eellulose acetate or other organic derivative of cellulose, and the weft or warp of'a normal or lmitation spun yarn contairiing regenemted cellu- 55 lose, and in this manner materials showing differential dyeing effects may be obtained. The following examples are given In order to illustr6te the invention, but thev are not to be considered as limiting it in any way:- .60 Example I A cellulose acetate yam of 750 denier is passed through a bath containing a 48% aqueous solution of dioxane between rollers driven to impart 65 a stretch of about 4: 1, the period of contact with the bath being about 2 minutes. A sup of the yarn Is allowed 6n the take-up rouer so that the. yam Is not completely broken, but individual filaments are ruptured. After washing, drying and, 70 collecting the yarn with a twist of 8. turns per inch ft is saponified to give a regenerated cellulose yam by passing it first through a wettingout bath containing water and then through a bath containing 4% aqueous -solution of caustic 76
[3]2,098,981 3 s6da containing 25% sodium chloride at about 75-85' C., the period of contact with the bath being 30-50 seconds. It is then washed, dried and rewound. 5 Example 2 A viscose yam of 500 denier having a twist of about .5 turn per inch is passed,through a bath containing 55% aqiieous sulphuric acid at 20'-25' C. between rollers driven to impart a @tretch 10 of about 2: 1. The period of contact with the bath Is about 2 minutes. In this irianlier a yam c6ntglning individuai broken filaments Is obtained, wliieh Is washed,,dried and given a twist 15 of about 5 turns per Inch. Example 3 A cuprammonium cellulose solution is spun through a precipitating bath in the normal man20 ner, and the thread so obtained is stretched about 75% between the spinning funnel and hardening bath by means of rollers tmvering at about 30 metres per minute and 52 metres per minute. In this manner a yarncontglrdng In25 dividual broken filaments is obtained. The yam is then passed through a hardening bath in which, if desired, it may be allowed to shrink in order to indrease the extensibility of the materigl, after which it is washed, dried and given so a twist of about 5 turns per inch. V,rhat I claim and desire to secure by
