US3425208A - Method for producing textured yarns of cellulosic fibres - Google Patents

Description

1969 F. B. SHIPPEE ET AL 3,425,203

HETHOD FOR PRODUCING TEXTURED YARNS OF CELLULOSIC FIBRES Filed Oct. 50, 1963 mvzm'ons I FRED BOSWELL SHIPPEE GUY EMMANUEL PERKINS V. JIIYi;

United States Patent 7 Claims Int. Cl. D02g 3/02, 3/36; D06m 1/00 ABSTRACT OF THE DISCLOSURE Textured yarns of cellulosic fibres are prepared by false-twisting at high spindle speeds by impregnating the yarn prior to false-twisting with a catalyzed heat-activated cross-linking agent and a mixture of mono-hydroxy oxyethylene oxy 1,2-propylene aliphatic monoethers.

This invention relates to methods for producing socalled textured yarns such as stretch, bulk, crim-ped, lively and fluffed yarns, from yarns of cellulosic fibres such as cotton, rayon, linen and the like. The invention also relates to novel compositions useful in the production of such textured yarns.

Prior to the present invention, textured yarns of the type set. forth have been manufactured commercially in substantial quantities from heat-settable thermoplastic yarns such as nylon, Dacron, Orlon and like yarns, by heating the thermoplastic yarn to plasticize the same, distorting or deforming the yarn while plasticized, for example, by twisting, to reorient the molecules of the yarn and then cooling the yarn while distorted or deformed to stabilize the yarn and cause the reoriented molecules of the yarn to be permanently set in the distorted or deformed configuration of the yarn. One such process is described in United States Patent No. 2,803,109.

While the commercial manufacture of the textured yarns has been highly successful in the case of thermoplastic yarns, it has not been possible to produce commercially at present high spindle speeds, textured yarns of cellulosic fibers such as cotton, linen and the like. Attempts have been made heretofore to produce textured yarns of cellulose fibres such as cotton, linen and the like by treating or impregnating such yarns with selected materials and then deforming and heating the treated yarn as described above to impart a permanent set thereto, but these prior attempts have not been satisfactory because the chemical formulations such as those disclosed in U.S. Patent 2,463,618, were found to be unusuable at present day high spindle speeds. At the high spindle speeds currently employed, resins, including cross-linking resins, caused increased and varying tensions in the yarns, undesirable roughness and embrittlement of the cellulose fibres in the yarn. It has been determined that these undesirable properties and characteristics resulting from the use of the cross-linking agents can be eliminated, or at least markedly reduced, by incorporating in'the yarn, either prior to, or during, impregnating of the yarnwith the cross-linking agent, a co-reactive material as more fully described hereinafter.

With the foregoing in mind, the principal object of the present invention is to provide a method for producing textured yarns of cellulosic fibres which overcomes the aforesaid difliculties and makes possible the commercial manufacture of textured yarns of cellulosic fibres.

It is also an object of the present invention to provide a method for producing commercially satisfactory cellulose fibre yarns of the textured types described which have a permanent set in which the individual fibres of the yarn exhibit a permanent inherent tendency to assume a 3,425,208 Patented Feb. 4, 1969 formation conforming to the configuration of the permanent set of the fibres.

More particularly, it is an object of the present invention to provide a method, employing high spindle speeds, for producing textured yarns of cellulosic fibres as set forth including impregnating the cellulosic fibres of the yarn with a catalyzed cross-linking agent for chemical reaction With the cellulose fibres of the yarn and a co-reactive material as hereinafter described.

According to the present invention, cellulosic fibres of yarns such as cotton, linen and the like are impregnated with a mixture of monohydroxy oxyethylene oxy 1,2-propylene aliphatic monoethers and with a catalyzed heatreactive cross-linking agent. The fibres can be impregnated simultaneously with the mixture of monoethers and the cross-linking agent, as from a common bath containing both materials, 'or the fibres may be impregnated with the mixture of monoethers independently of the crosslinking agent. In any event, the final impregnated yarn is mechanically manipulated, for example by twisting or otherwise, to distort or deform the impregnated fibres to the desired configuration and, while the fibres are thus distored or deformed, the yarn is heated to a predetermined temperature to effect chemical reaction between the cellulose fibres and the cross-linking agent.

These and other objects and features of the invention are hereinafter more fully set forth and described with reference to certain typical embodiments, one form of apparatus for practicing the present invention being shown in the accompanying drawing in which:

FIG. 1 is a vertical sectional view transversely through apparatus especially adapted for practicing the present invention; and

FIG. 2 is a front elevational view of the portion of the apparatus disclosed in FIG. 1.

Referring to the drawing,. the apparatus shown may be used to practice the method of the present invention. The yarn 1 is drawn laterally from a package P, supported in an overhead creel c through a snubber or guide 2 and thence downwardly through a series of yarn guides 3, 4, 5 and 6, respectively, to a driven furnishing device 7. From the furnishing device 7 the yarn 1 passes downwardly and thence through the laterally spaced loops of a guide device 8 which is immersed in a bath 9 of yarn treating materials contained in a pan or trough 10, the guide 8 being arranged in the trough 10 so that the yarn 1 passing therethrough will be immersed in the bath of the treating materials for a brief portion of its travel through the apparatus sufficient to impregnate the yarn and its fibres with the treating materials.

The treating materials in the bath 9 with which the yarn 1 and its fibres are impregnated in accordance with the present invention, comprise a heat-reactive crosslinking agent capable of reacting with the cellulosic hydroxyls of the yarn fibres and, in the preferred embodiment, the mixture of monoethers, either with or without additives such as Wetting agents, finishing materials and the like as may be desired or necessary to meet the particular requirements of the yarn product being produced. Although not shown in the drawing, the yarn 1 may be passed preliminarily through a separate bath containing the mixture of monoethers before passing through bath 9, in which case bath 9 need not contain the mixture of monoethers. These various materials are described in detail hereinafter, together with specific examples of the use thereof in producing textured yarns according to the method of the present invention.

From the bath 9 the yarn 1 passes through a suitable tension device 11, for example, a gate tension, which functions, inter alia, to properly control the tension of the impregnated yarn 1 as the latter continues its passage upwardly through the heater device 12 and false twist 3 spindle 13 to feed rolls 14. From feed rolls 14 the yarn passes ultimately to a driven take-up roll 15 which is rotationally driven by surface contact with a drive roll 16 at a speed less than the feed rolls.

The false twist spindle 13 is of the high speed beltdriven type and operates in well-known manner to impart a high degree of twist to the yarn 1. The twist imparted to the yarn by the false twist spindle 13 extends in the yearn from the spindle 13 downwardly through the heater 12 to the gate tension 11 which performs the additional function of preventing the twist in the yarn from extending beyond the tension device 11.

As the impregnated yarn traverses the heating device 12 it passes coaxially through a longitudinally split tube 17 where the twisted and impregnated yarn is heated to the desired degree. The lower portion of the tube 17 is heated electrically by a block type heater 18, and the upper and major portion of the length of the tube 17 is heated electrically by a separate block type heater 19. Separate heaters 18 and 19 are employed because it has been found that the lower portion of the tube 17 must be heated to a temperature sufficiently high to vaporize or burn-off any excess of the impregnating solution which may be discharged from the rapidly twisting yarn by centrifugal force. If this is not done, the excess impregnating solution discharged from the yarn soon builds up on the interior surface of the heater tube 17 to the extent that the practical operating efliciency of the apparatus is substantially reduced. The upper portion of the heater tube 17 is heated by the heater 19 to the temperature required to effect the cross-linking reaction.

Thus, as the highly twisted impregnated yarn 1 traverses the tube 17 of the heating device 12, the yarn is heated to a temperature sufficient to cause the selected cross-linking agent to react chemically with the cellulosic hydroxyl groups of the fibres of the yarn thereby cross-linking or chemically bonding together the cellulose fibres of the yarn in the highly twisted configuration produced by the false-twist spindle 13.

The false twist spindle 13 functions in its conventional manner well-known in the art to remove the twist from the yarn as the yarn leaves the spindle. The untwisted yarn then passes to the draw or feed rolls 14 by which it is advanced or fed at a predetermined rate to the take-up roll 15.

As the result of this continuous processing in accordance with the present invention, a textured yarn of cellulosic fibres is produced having a permanent crimp, wave or fluff set into the yarn. By this is meant that the cellulosic fibres in the yarn are permanently set in the yarn according to the formation of the yarn at the time of the heat-induced chemical reaction between the crosslinking agent of the impregnating bath 9 and the cellulosic hydroxyl groups of the yarn fibres, so that the individual fibres of the yarn have an inherent tendency to assume the formation which they had at the time of setting.

Referring now more particularly to the cross-linking agent employed in the impregnating bath 9 in practicing the method of the present invention, this, as is well known, is an organic compound having functional groups, more than one and preferably two or hree, rendering the compound capable of reacting polyfunctionally with cellulosic hydroxyl groups of the yarn fibres.

Examples of suitable cross-linking agents include the following: dimethylol ethylene urea, dimethylol dihydroxyethylene urea, dimethylol N-ethyl triazone, tris-methoxymethyl melamine, diacetoxymethyl ethylene thiourea, vinyl cyclohexene dioxide, glyoxal, glutaraldehyde, butanol hemiformal, disodium sulfatoethyl sulfone, bis hydroxyethyl sulfone, methylene bis acrylamide, the diketene of glutaric acid, the bis pyridinium salt of chloromethylated glycols, tris aziridinyl phosphine oxide, tetramethylol acetylene diurein, bis hydroxyethylene urea, glycerin dichlorohydrin, dimethylol urea, diglycidyl ether of glycerol, dimethylol alkyl hydrazines, dimethylol alkyl carbamates, bis methoxymethyl uron, dimethylol oxamide, dimethylol paracresol, dimethylol acetone, formaldehyde, glycol formals, and the like, as well as blends of two or more of these, such as a blend of dimethylol N-ethyl triazone and tris-methoxy methyl melamine. Preferred cross-linking agents are dimethylol ethylene urea, dimethylol dihydroxyethylene urea, dimethylol N-ethyl triazone and blends of dimethylol N-ethyl triazone with tris-methoxy methyl melamine in a weight ratio between about 2:1 and about 1:2, preferably about 1:1.

The foregoing cross-linking agents may be employed as to produce textured yarns of cellulosic fibres in accordance with the present invention by providing a concentration of the selected cross-linking agent in the impregnating bath 9 of between about 2.5 and about 20%, preferably between about 7.5 and about 12.5%, by weight, based on the weight of the bath.

The reaction of the cross-linking agents with the cellulosic hydroxyl groups of the yarn fibres, as is wellknown, is normally catalyzed, and most of the crosslinking agents set forth above require the use of selected acid or basic catalysts depending upon the particular crosslinking agent employed. For example, the epoxy, aziridinyl, methylol and aldehy-dic compounds require acidic catalysts, such as ammonium chloride, magnesium chloride, oxalic acid, zinc nitrate, amine hydrochlorides, zinc fiuoroborate, zinc acetate, and the like. On the other hand, the vinyl sulfone derivatives, the chlorohydrins, and the like require alkaline catalysts, such as sodium hydroxide, potassium carbonate, triethanol amine, and the like. The amount of catalyst employed will depend, as well known, upon the particular cross-linking agent used and amount thereof as well as upon the particular catalyst. Generally the catalyst is present in an amount between about 5 and about 50%, based on the weight of the cross-linking agent.

The mixture of monoethers employed in accordance with the present invention, is a mixture of monohydroxy oxyethylene oxy 1,2-propylene aliphatic monoethers. In this mixture of monoethers, ethylene oxide and 1,2-propylene oxide are combined as oxyethylene and oxy 1,2- propylene groups in a ratio which is at least one-third part of 1,2-propylene oxide for each part of ethylene oxide, by weight. Generally, the ratio of 1,2-propylene oxide does not appreciably exceed about nine parts thereof per part of ethylene oxide. The aliphatic alcohol used in preparing the monoethers, and from which the aliphatic monoether group is derived, may contain from one to fourteen carbon atoms. However, those in the lower end of the range, that is containing up to and including four carbon atoms, are preferred. In such case the aliphatic ether group may be that of methyl, ethyl propyl or butyl. The mixture of monoethers employed in accordance with the present invention, will have a molecular weight ranging from about 500 to about 3000, and preferably not over about 1500. A particularly advantageous mixture of monoethers in this regard is one having the following characteristics:

Apparent specific gravity, 20/ 20 C 0.991 Viscosity index (ASTM D-567-53) 97 Viscositycentistokes at 210 F. Approx. 3

These monoether mixtures and their preparation are more fully described in US. Patent 2,425,755, and reference may be made thereto.

The concentration of the mixture of monoethers in the impregnating bath 9, or in a prior separate bath, may vary somewhat, although it is usually between about 0.5 and about 5%, preferably between about 1 and about 3%, by weight, based on the weight of the bath. I

In addition to the aforesaid cross-linking agents and mixture of monoethers, the impregnating bath 9 may contain a wetting agent compatible with the othercomponents of the bath. These wetting agents do not function chemically as do the cross-linking agents, but function in the customary manner of a wetting agent to insure maximum penetration and impregnation of the agents into the yarn. Also, other chemicals normally applied to textiles can be included in the impregnating bath 9.

A particularly valuable composition, in the form of an aqueous concentrate adapted to be diluted with water to provide an impregnating bath for use according to the present invention, contains, per 100 parts by weight of concentrate: from about 30 to about 65 parts of dimethylol ethylene urea, from about to about 45 parts of water, from about 5 to about 20 parts of the mixture of monoethers, about 5 parts of zinc nitrate and about 5 parts of zinc acetate. A-preferred concentrate in this regard contains, per 100 parts by weight of concentrate: about 40 parts of dimethylol ethylene urea, about 40 parts of water, about 10 parts of the mixture of monoethers, about 5 parts of zinc nitrate and about 5 parts of zinc acetate The impregnating bath 9 comprises a solution of the selected materials. An aqueous solution of the materials is preferred but other selected solvents may be employed which are compatible with the selected chemical materials and the cellulosic fibres of the yarn to be processed. The following are typical examples of aqueous solutions of cross-linking agents, catalysts and the mixture of monoethers which may be used to produce textured yarns of natural cellulose fibres according to the present invention. In each example the percentages set forth are the percentages by weight of solids based on the total weight of the bath, the balance being water:

Example 1 Percent Dimethylol ethylene urea 10 Zinc nitrate l Mixture of monoethers 2 Example 2 Dimethylol dihydroxyethylene urea 7.5 Zinc nitrate 1 Mixture of monoethers 1 Example 3 Dimethylol N-ethyl triazone 12.5 Zinc nitrate 1 Mixture of monoethers 2 Example 4 Percent Dimethylol N-ethyl triazone 5 Tris-methoxy melamine 5 Magnesium chloride hexahydrate 4 Mixture of monoethers 3 The following are typical examples of the production of texture yarns such as stretch cotton by the method of the present invention. To produce a stretch cotton having high stretch and recovery characteristics for use in bathing suits, girdles, and like garments, a 50 count two ply black combed cotton yarn twisted 18 turns Z per inch in the singles and turns Z per inch in the ply, was impregnated with the solution or bath of Example 1 above in the manner previously described. The yarn was S twisted 93.3 turns per inch by the spindle 13 operating at a speed of 30,000 r.p.m. and while thus twisted was heated during passage through the heater device 12 under a tension of grams. The heater was heated to a temperature of 465 F.

A stretch cotton having medium stretch and recovery characteristics suitable for use in double-knit, jersey and like fabrics was produced from two ends of 50 count singles ecru combed cotton yarn twisted 18 turns Z per inch. The yarn was impregnated with the solution or bath of Example 2 above in the manner previously described. The yarn was then S twisted 73.5 turns per inch by the spindle 13 operating at a speed of 30,000 r.p.m. and while thus twisted was heated during passage through the heater device 12 under a tension of 20 grams. Heater temperature was 560 F. t

A stretch cotton having medium stretch and recovery characteristics suitable for use in socks, jersey knits and like garments, was produced by processing a 36 count two ply bleached combed cotton yarn twisted 16 turns Z per inch in the singles and 11 turns S per inch in the ply was impregnated with the solution or bath of Example 3 above in the manner previously described. The yarn was then Z twisted 52 turns per inch by the spindle 13 at a speed of 40,000 r.p.m. and while thus twisted was heated during passage through the heater device 12 under a tension of 25 grams. Heater temperature was 620 F.

To produce a stretch cotton having stretch and recovery characteristics suitable for use in socks, a 30 count two ply carded cotton yarn twisted 18 turns S per inch in the singles and 10 turns Z per inch in the ply was impregnated with the solution or bath of Example 4 above in the manner previously described. The yarn was then S twisted 46.5 turns per inch by the spindle 13 driven at a speed of 30 r.pm. and while thus twisted was heated during passage through the heater device 12 under a tension of 30 grams. Heater temperature was 540 F.

While the foregoing examples, and the apparatus shown in the drawing, all embody false twisting of the yarns to orient or position the fibres in the yarn to the desired configuration in which they are permanently set by chemical reaction between the cross-linking agent and the cellulose hydroxyl groups, it will be apparent that the invention is not limited to methods or procedures involving the use of a false twist spindle. To the contrary, it is not important that a particular means or method be employed to orient or position the fibres of the yarn. All that is required is that the yarn fibres be positioned in the desired configuration during the cross-linking reaction with the cellulose hydroxyl groups to set the fibres permanently in that position so that after processing the fibres of the yarn have a permanent inherent tendency to assume the formation or configuration in which set.

From the foregoing it will be apparent that the present invention provides a method for producing, at high speed spindles, commercially satisfactory cellulose fibre yarns of the textured types described which have a permanent set in which the individual fibres of the yarn have a permanent inherent tendency to assume a formation conforming to the configuration of the permanent set of the fibres. Moreover, fabrics made of yarns processed according to the present invention are characterized by improved properties such as increased warmth, less weight, greater yield, greater softness of hand, improved drape and the like.

While certain embodiments of the invention have been set forth and described it is not intended to limit the invention thereto and changes and modifications may be made and incorporated as required in the adaptation and use of the invention within the scope of the claims.

We claim:

1. In the production of permanently textured yarns of cellulosic fibres selected from the group consisting of cotton, rayon and linen wherein the cellulosic fibres of the yarn are impregnated with an acidic catalyzed heatactivated dimethylol ethylene urea cross-linking agent capable of reacting with the cellulosic hydroxyl groups, the impregnated yarn is twisted and the impregnated yarn, while in said twisted configuration, is heated to dry said impregnated yarn and to effect chemical reaction between said cross-linking agent and the cellulosic hydroxyl groups thereby to set said fibres permanently in said twisted configuration so that the fibres have an inherent tendency to assume said twisted configuration after untwisting, and thereafter untwisting said yarn; the improvement which comprises the steps of impregnating said yarn with a solution of a mixture of monohydroxy oxyethylene 1,2-oxypropylene monoethers of alkyl alcohols having from 1 to 14 carbon atoms, said mixture of monoethers having a molecular weight of from about 500 to about 3000, in

addition to said cross-linking agent, and thereafter twisting said impregnated yarn as a continuously running length at a spindle speed of at least about 30,000 r.p.m.

2. The method of claim 1 wherein said yarn is impregnated simultaneously with said cross-linking agent and said mixture of monoethers in a common bath solution.

3. The method of claim 2 wherein the cross-linking agent is present in the solution in from about 2.5 to about 20%, by weight, and the mixture of monoethers from about 0.5 to about by Weight of the solution.

4. The method of claim 3 wherein the cross-linking agent is present in the solution in from about 7.5 to about 12.5%, by weight, and the mixture of monoethers from about 1 to about 3%, by weight, of the solution.

5. The method of claim 1 wherein in said mixture of monoethers the oxyethylene groups and the 1,2-oxypropylene groups are in a ratio of at least one-third part of 1,2-propylene oxide per part of ethylene oxide.

6. The method of claim 5 wherein the oxyethylene groups and the 1,2-oxypropylene groups are in a ratio of no more than nine parts of 1,2-propylene oxide per part of ethylene oxide.

7. In the production of permanently textured cotton yarns wherein the fibres of the yarn are impregnated with an acidic catalyzed heat-activated dimethylol ethylene urea cross-linking agent capable of reacting with the cellulosic hydroxyl groups of said cotton, the impregnated yarn is twisted and the impregnated yarn, while in said twisted configuration, is heated to dry said impregnated 3 yarn and to effect chemical reaction between said crosslinking agent and the cellulosic hydroxyl groups thereby to set said fibres permanently in said twisted con-figuration so that the fibres have an inherent tendency to assume said twisted configuration after untwisting, and thereafter untwisting said yarn; the improvement which comprises the steps of impregnating said yarn simultaneously, from a common bath solution, with said crosslinking agent and a mixture of monohydroxy oxyethylene 1,2-oxyprop'ylene monoethers of alkyl alcohols having from 1 to 4 carbon atoms, said mixture of monoethers having a molecular weight of from about 500 to about 3000 and a ratio of 1,2-oxypropylene groups to oxyethylene groups from one-third to none parts of 1,2-propylene oxide per part of ethylene oxide, the cross-linking agent being present in the solution in from about 7.5 to about 12.5% solids by weight and the mixture of monoethers being present in the solution in from about 1 to about 3% solids by weight, and thereafter twisting said impregnated yarn as a continuously running length at a spindle speed of at least about 30,000 r.p.m.

References Cited UNITED STATES PATENTS 2,208,632 7/1940 Dreyfus 8117 X 2,403,304 7/1946 Robinson et al. 57l64 X 2,407,105 9/1946 Seymour et al. 57l64 X 2,425,755 8/1947 Roberts et al 260-615 2,895,288 7/1959 Yoo 8-116.4 X 3,116,967 1/1964 Goldstein et al. 8-116.3. X 3,127,732 4/1964 Brown et al 8-420 X FOREIGN PATENTS 1,177,996 12/ 1958 France.

710,441 6/1954 Great Britain.

233,148 10/1964 Switzerland.

OTHER REFERENCES Speel, Henry C., et al.: Textile Chemicals and Auxiliaries, 1957, pp. 114-122 and 249; Reinhold Publishing Corp., New York, NY.

NORMAN G. TORCHIN, Primary Examiner.

H. WOLMAN, Assistant Examiner.

US. Cl. X.R.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 ,425 ,208 February 4 1969 Fred Boswell Shippee et a1.

It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 3 line 9 "yearn" should read yarn line 61 "hree" should read three Column 5, line 49, "Trismethoxy melamine" should read Tris-methoxy methyl melamine Column 6, line 13, "produec" should read produce Column 8, line 5, "none" should read nine Signed and sealed this 3rd day of February 1970.

(SEAL) Attest:

Edward M. Fletcher, Ir.

Attesting Officer Commissioner of Patents WILLIAM E. SCHUYLER, JR.

Images