US 3921377 A
In a procedure for dyeing a length of fabric by conveying the fabric in the direction of its length through a dye station where the fabric is impregnated with a quick-setting dye, the dye is caused to non-uniformly color the fabric with a generally longitudinal, randomly varying pattern effect, by causing the fabric to pass through the station in a longitudinally twisted state. In order to enhance the effect of this procedure, and in particular to vary the general nature of the color variation produced, the fabric is manipulated ahead of the dye station by periodically varying its degree of twist and/or degree of compression transverse to its length.
Description (OCR text may contain errors)
United States Patent [1 1 Snyder Nov. 25, 1975 1 PRODUCTION OF DYED FABRICS  Inventor: Michael E. Snyder, Albermarle,
 Assignee: E. J. Snyder & Co., Inc., Albemarle,
 Filed: Oct. 26, 1973 21] Appl. No.: 409,885
 U.S. CI 57/35; 8/151; 68/205 R; 57/165  Int. Cl. D06B 3/24; D068 1 1/00  Field of Search 57/7, 162, 35, 164, 34 AT, 57/165,153,l56,l62;8/l51.l,151.2,149;
3,102,711 Neale .1: 57/165 x Reeder et a1. .4 8/1512 Schuierer 8/151  ABSTRACT In a procedure for dyeing a length of fabric by conveying the fabric in the direction of its length through a dye station where the fabric is impregnated with a quick-setting dye, the dye is caused to non-uniformly color the fabric with a generally longitudinal, randomly varying pattern effect, by causing the fabric to pass through the station in a longitudinally twisted state. In order to enhance the effect of this procedure, and in particular to vary the general nature of the color variation produced, the fabric is manipulated ahead of the dye station by periodically varying its de gree of twist and/or degree of compression transverse to its length.
9 Claims, 4 Drawing Figures US. Patent Nov. 25, 1975 U.S. Patent Nov. 25, 1975 Sheet 2 of3 3,921,377
U.S. Patent Nov. 25, 1975 Sheet30f3 3,921,377
PRODUCTION OF DYED FABRICS BACKGROUND OF THE INVENTION The present invention relates to a method and apparatus for dyeing lengths of fabric, inparticular by conveying the fabric in the direction ofits length through a suitable dye station from which dye is dispensed in a continuous operation.
The invention is particularly concerned with methods and apparatus of the type in which a substantially uniform dye distribution is provided by the dye station, as opposed to procedures designed to produce a regular pattern. i.e.. printing procedures.
In the specific field to which the invention relates. it is usually desired to color the entire fabric as uniformly as possible. However, there is a market demand for garments made of fabrics having a randomly varying. nonuniform coloration.
While various efforts have hertofore been made to satisfy this demand, none of them has been completely satisfactory either because they do not produce a sufficiently random effect or because they involve time consuming manual operations and are thus unacceptably costly.
SUMMARY OF THE INVENTION It is a primary object of the present invention to overcome these drawbacks.
A further object ofthe invention is to produce fabric having a coloration which varies randomly within selected limits.
A further object of the invention is to produce such fabrics at a high production rate and at low cost.
The invention is applicable to procedures in which a length of fabric is dyed by conveying the fabric in the direction of its length through a dye station where the fabric is impregnated with a quick-setting dye. The objects according to the invention are achieved by imparting a longitudinal twist to the fabric ahead of the dye station to cause the fabric to pass through the station in a twisted state. whereby the dye applied to the fabric will non-uniformly color the fabric with a generally longitudinal, randomly varying pattern effect.
The objects according to the invention are further achieved by manipulating the twisted fabric ahead of the dye station so as to impart variations to the effect produced within the dye station.
The objects according to the invention are additionally achieved by subjecting the fabric to subsequent operations which prevent the non-uniformity of the coloration imparted in the dye station from being diminished.
BRIEF DESCRIPTION OF THE DRAWINGS FIGS. Ia and lb are elevational side views of successive portions ofdyeing apparatus constructed and operated according to the present invention.
FIG. 2 is an elevational view of a unit according to the invention which can be used in the apparatus of FIG. 1.
FIG. 3 is a photographic reproduction of a length of dyed fabric according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates one preferred embodiment of apparatus for carrying out the present invention. The primary purpose of this apparatus is to pass a length of fabric through a dye station while the fabric is twisted about its longitudinal axis. It has been found that the color pattern effect produced in the dye station can be varied by varying one or more of: the rate of travel of the fabric; the degree of twist. and the direction of twist of the fabric as it passes therethrough. The effect can also be varied by controlling the diameter ofthc twisted fabric. It can further be varied chemically by controlling the rate of diffusion of dye from portions of the fabric which are directly impregnated thereby to regions of the fabric which are not directly impregnated. this being achieved, for example. by providing the dye with a suitable amount of a penetrating agent.
As is shown in FIG. I. a length of fabric I. which preferably is in the form of knit greige goods. is initially supplied in a piled condition in a box 3. The top of the box is provided with a circular hoop 5 oriented to coincide with the open top of the box and defining a circular outlet opening through which fabric is drawn from the box. The box 3 is placed on a turntable 7 supported by a shaft 8 driven by a suitable motor disposed in a stationary housing 9. The leading end of fabric I is drawn over a metal detector 11, of any suitable type. The leading end of the length of fabric is introduced into a dye station I5 to pass between a dye cylinder 21 and a belt 17 driven by rollers 1).
Cylinder 21 is not itself directly driven by any drive unit. Rather. it is mounted to be freely rotatable and the fabric is pressed between cylinder 21 and belt 17 so that the fabric is advanced by the belt and. in turn, ro tates the cylinder.
Upon initial introduction ofthe leading edge offabric I into the dye station. turntable 7 is placed into rotation to impart a suitable twist to the length of fabric. The rate of rotation ofturntable 7 is selected on the basis of the rate at which the fabric is to pass through the dye station and the degree of twist to be imparted to the fabric.
Thus. for example. for a fabric having a weight of [.6 yards per pound. a good result has been achieved by advancing the fabric through the dye station at a speed of 50 yards per minute while rotating turntable 7 at a rate of IS rpm.
At station I3, the twisted fabric is displaced horizontally transverse to its length. i.e.. along the axis of cylin der 21, in a cyclic manner from one axial end of the cylinder to the other in order to distribute the wear over the entire surface of the cylinder. The displacement could be at a rate of several cycles per minute and can be effected either manually, by the workman, or mechanically.
The twisted fabric may be continually or periodically manipulated by a workman at work station 13. This manipulation can serve to alternatingly provide a tighter and looser twist and/or to vary the degree of compression of the fabric transverse to its length. The latter can be achieved by alternately squeezing and releasing the fabric. All of these manipulations will vary the specific appearance of the generally longitudinal pattern effect produced on the fabric by the application of dye at station IS.
Circular hoop 5 serves to prevent the fabric from being caught on the corners of box 3 and assists in twisting the fabric. The sliding of the fabric along the inner surface of the hoop helps to impart a uniform twist thereto. If the hoop were not provided. the fabric would wedge into the corner of the box nearest the dye station and would then quickly slide to the next succeeding corner as the turntable rotates. This would in terfere with the establishment of a uniform degree of twist along the length of the box. Hoop is preferably constituted by a metal ring having a rectangular cross section, with a rubber layer attached to the inner surface of the ring. The rubber protects the fabric and provides a frictional contact surface for the fabric and thus aids in imparting the desired twist thereto.
In the dye station 15, the fabric 1 is compressed between roller driven belt 17 and rotatable dye cylinder 21. The device is the type used for continuous batch dyeing. The fabric advances through the station under the influence of the advancing movement of belt 17 and during this travel rotates cylinder 21.
Cylinder 21 is constituted by a very thin, flexible metal sheet provided with a large number of small perforations. The ends of cylinder 21 can be constituted by relative rigid circular collars between which the metal sheet is mounted. The cylinder may be open at its ends and supported by sets of rollers which may bear against the collars defining the ends of the cylinder.
This construction leaves the interior of cylinder 21 accessible for receipt of tubes 23 and 25 which extend substantially the entire length thereof. These tubes are disposed adjacent the cylindrical wall of cylinder 2] close to the region of contact with fabric 1. Tubes 23 and 25 are mounted to remain stationary while the cyl inder rotates in contact with the fabric.
Each of the tubes 23 and 25 is provided with a longitudinal slot located generally at the lowermost point of its periphery, i.e., facing the fabric 1. Tube 23 is connected to a vacuum source 27 producing a vacuum which communicates with the fabric through the slot in tube 23 and the perforations in cylinder 21 so as to extract a substantial portion ofthe air trapped in fabric 1. Tubes 23 and 25 are provided, at least along each side of their respective slots, with a friction-reducing coating of a material such as Teflon or a polyamide. Cylinder 21 slides against these coatings when it is rotated by a length of fabric.
Tube 25 is located immediately downstream of tube 23 and supplies, via its slot, the desired dye solution to the inner surface of cylinder 21. This solution passes through the perforations in cylinder 21 and penetrates the fabric, this penetration being aided by the fact that the dye liquid tends to replace the air just previously removed from the fabric by the action ofthe vacuum in tube 23.
Typically, each of the slots in tubes 23 and 25 has a width of the order ofthree quarter inch and the spacing between slots is of the order of 1 inch.
In order to achieve the desired coloration effect, use is made of quick-setting, fiber reactive dyes. The quicksetting character of the dye prevents it from transferring, or diffusing, to any substantial degree from one part of the fabric to another subsequent to passage between belt ]7 and roller 2l.
The described apparatus at station is a vacuum impregnator, which is known per se. The fabric is preferably dyed according to the known exhaust dye method and the ingredients of the dye solution are selected according to known principles on the basis of the color desired.
In the practice of the exhaust dye method, the dye solution is a mixture of a dye and an alkali in water or a bath of another liquid. A suitable mixture for dyeing operations according to the invention could be consti- 4 tuted by four parts dye and one part alkali, and the alkali could be constituted by a mixture of sodium silicate and caustic soda.
In order to permit the dyeing operation to be carried out on a continuous basis, the ingredients of the dye solution are preferably stored in separate containers 30, 31 and 32, although only two containers could be used. For example, the dye could be stored in one ofthe containers, and soda ash in the second of the containers. These two ingredients are delivered to a mixing chamber 34, with the rate of supply of each component being controlled by a suitable controlled valve 36, 37 or 38, respectively. If it is desired to provide initially a large quantity of the dye, particularly when a mixture of four parts dye to one part alkali is to be used, the dye ingredient could be stored in two containers and the alkali in the third container. These valves are operated, by a suitable control system, to supply the individual ingredients at suitable relative rates. The rate of supply is selected to assure that the dye mixture formed in chamber 34 will be delivered to the fabric a sufficiently short time after the components thereof are brought together.
The dye treatment according to the invention can be performed on virtually any type of fabric, be it of natural fibers, man-made fibers, or blends thereof. It can also be performed on non-woven or woven fabrics, in addition to knitted fabrics.
The dye used to achieve the novel effect according to the invention can be virtually any type which is known to be compatible with the selected fabric. The requirement that the dye be quick-setting is satisfied by practically all dyes currently used in the industry and is a particular characteristic of dyes currently used for dyeing synthetic fabrics.
Thus, for a given material, the dye can be selected and applied according to the known principles employed in the dyeing industry and disclosed in various standard reference publications, one example of which is DYEING MAN-MADE FIBERS AND BLENDS, General Aniline & Film Corp. (1967). For cellulosic fibers, use is preferably, but not exclusively, made of fiber reactive dyes.
The fabric employed can have any suitable physical form, such as tubular or flat.
The present invention can also be employed to impart multicolored effects to fabrics. To achieve such effect a length of fabric is first dyed in the manner described above with reference to the drawing. Then, without being untwisted, and after the dye has been permitted to set, the length of twisted fabric is again passed through the same or another dye station 15 where a dye producing a different color is applied. Thereafter the fabric is aged and subjected to any necessary further treatments.
The resulting fabric will then have a multicolored appearance defined by individual areas, some of which are uncolored, others of which have the colorations of the respective dyes, and others of which have a coloration determined by the combined effect of the two dyes. Highly unusual and pleasing effects can be achieved in this manner.
One example of a suitable dye which could be used in the practice of the present invention is a monoazo dichlorotriazinyl derivative such as C.I. Reactive Orange 1. Such a dye is disclosed in the 1963 supplement of the publication COLOUR INDEX, second edition, at page S 493, The Society of Dyers and Colourists, England To assure that the dye will penetrate entirely through the body of twisted fabric, the dye solution can be supplemented by a suitable penetrating agent which overcomes the resistance to wetting created by the knitting oils remaining in the fabric. Such penetrating agents are known per se and, in the practice of the present invention, it has been found that such an agent assists in the migration, or wicking-out of the dye so as to produce intermediately shaded regions.
In the practice of the present invention, it is desired to produce fabrics having randomly shaped, but generally longitudinally elongated, regions of saturated color, similarly shaped regions which remain substantially uncolored, and regions having a color density which varies between saturated and uncolored. It has been found that a very pleasing appearance is achieved if, along every linear yard of fabric there are at least some uncolored regions constituting no more than of the fabric area. FIG. 3 shows a length of fabric manufactured according to the invention and possessing these characteristics.
After leaving the dye station 25, the fabric is conveyed around guide rollers 41, 42, 43 and 44 to a station 46 provided with two rollers 51 and 52 between which the fabric is conveyed.
At least one of the guide rollers, such as 42, is mounted on a pivot arm 45 to which a suitably adjusted force is applied, as schematically represented by a spring, in order to maintain the length of fabric under a desired degree of tension.
Rollers S1 and 52 are mounted in a known manner (not shown) to be pressed toward one another in a manner to apply a substantially constant, controlled pressure to the fabric. The pressure provided by these rollers serves to force the dye into the fabric to produce the desired effect. It is desirable that the selected pressure level be maintained relatively constant since it has been found that when the fabric is subjected to an insufficient pressure level, undesired irregularities occur in the resulting pattern.
The pressure applied to the fabric by rollers 51 and 52 will serve to squeeze excess dye therefrom. This dye is collected in a catch pan 55 and recirculated therefrom, by a pump 56, to the container 34.
Beyond station 46, the fabric is fed through a pot eye 53, which is simply a metal ring having a smooth ceramic insert. Ring 53 is fixed in position with its center substantially coaxial with a line located in the space between rollers 51 and S2 midway between their ends and normal to the line joining the centers of the rollers. The purpose of ring 53 is to cause the fabric to be guided along a straight line away from rollers 51 and 52 so as to only contact the rollers at their nip. This helps to prevent dye from contacting and flowing onto the rollers and from thus being reapplied to the fabric. The pot eye also suppresses the cyclic movement ofthe fabric horizontally transverse to its length, which movement was introduced at the input end of dye station 15.
The fabric, after passing through pot eye or ring 53 located midway between the sides of the device, is conveyed over a further driven guide roller 58 and then folded into a plastic bag held in a further box 40. Roller 58 is covered with a suitable rough material to provide frictional contact with fabric 1. The roller is driven at a suitable rate to pull the fabric through ring 53 in order to maintain the desired tension in the fabric length between ring 53 and rollers 51, 52.
After a given length of fabric has been introduced into the plastic bag, the bag is sealed and removed from the box. Another plastic bag is then introduced into the box for receiving the next succeeding length of fabric. The bag which has been removed remains sealed for the period of time required for the dye to completely react. The period required could be of the order of 2 hours.
After this ageing period, the fabric may be removed from the bag, scoured and rinsed to remove unfixed dye and residual alkali. Then, in a further apparatus, water is extracted from the fabric as it is untwisted and a softening agent is applied.
The metal detector 11 upstream of dye station 15 is not essential to the dyeing operation according to the invention. However, when use is made of a thin. flexible member for cylinder 21, it has been found that any metal present in the fabric can seriously damage the cylinder,
lnsofar as concerns the results achieved by the present invention, it has been found that the twisting of a length of fabric before it passes through the dye station 15, together with the use ofa quick-setting dye, results in the production of a fabric which possesses an attractive, rough, elongated pattern effect. The quick-setting character of the dye employed assures that it will not be transferred from one part of the fabric to another after it has been supplied to the receiving box 40.
For some purposes, it may be desired to cause the rate of movement of fabric 1 through dye station 15 to vary with the thickness of the fabric. For this purpose, a suitable thickness detector could be provided and connected to act in such a manner as to reduce the rate of feed of fabric through station 15, the rate of rotation of turntable 7, and the rate of delivery of the dye ingreclients, as the fabric thickness increases.
The portion of the apparatus including dye station [5, rollers 41-44 and nipping rollers 51 and 52 could be constituted by a known continuous pad batch dyeing vacuum impregnator of the type manufactured and sold by Sir James Farmer Norton & Co., Ltd., Manchester, England. In such a device the dimension ofcylinder 21, belt 17 and the rollers thereafter, normal to the plane of the drawing, is about 5 feet.
As has been mentioned above, the cyclic horizontal displacement of the fabric transverse to its length, at station 13, could be achieved mechanically, as well as by a worker. FIG. 2 illustrates one possible embodiment of a mechanical traversing unit which serves this purpose.
The device shown in FIG. 2 includes a cone 61 whose diameter decreases toward station l5. Cone 61 is disposed in, and supported by a housing 63 provided with slide openings via which it is slidably mounted on guide rails 65. Rails 65 are in turn stationarily supported by posts 67 fixed to the ground.
The carriage 63 is mounted to slide freely along the length of rails 65 between posts 67. For driving the carriage along this path, there is provided a pivot lever 69 having one end pivotally connected to the carriage at pivot point 7]. Lever 69 is provided with an elongated slot 69 in which slidably engages a fixed pivot pin 73 attached to a stationary support 75 which is also fixed to the ground.
There is also provided a drive disc 77 carrying a drive pin 79 which also slidably engages in slot 69'. Disc 77 is connected to the shaft of a suitable drive motor (not shown) selected and controlled to rotate at a speed corresponding to the desired rate of cyclic horizontal displacement of cone 6i. As disc 77 rotates, pin 79 causes lever 69 to undergo an oscillatory movement which displaces carriage 63, and thus cone 7], along rails 65. Lever 69 pivots about pin 73 under the influence of the rotary movement of pin 79 and each rotation of disc 77 produces one full cycle in the movement of carriage 63 back and forth along the length of rails 65.
When the arrangement shown in FIG. 2 is employed in the machine of FIG. I, it is located at station 13 and oriented so that the movement of carriage 63 along rails 65 is normal to the plane of FIG. 1. i.e., parallel to the axis of cylinder 21. At the start of operation. the leading end of the fabric is fed through cone 6] and introduced between cylinder 21 and roller 17. While the fabric is being fed through dye station 15. disc 77 is caused to rotate so as to cause the fabric to be continuously and cyclically displaced along the axis of rotation of cylinder 21.
If desired, disc 77 could be linked to the drive for belt 17 so as to cause the rate ofdisplacement of cone 61 to maintain a fixed relationship with the rate of movement of fabric through the dye station. In addition. cone 61 could be mounted and driven so as to rotate about its own axis in an oscillatory manner, and thus to provide to a certain degree the manipulation performed by a workman at station 13 when a mechanical system is not provided at that station. In this case. it might be desirable to provide the interior surface of cone 61 with a friction coating. for example of rubber, to enable it to grip the fabric sufficiently to cause the twist thereof to vary as the cone rotates in such an oscillatory manner.
The arrangement shown in FIG. 2 is, of course. only exemplary, and numerous other mechanical manipulat ing structures can be envisioned.
It will be understood that the above description of the present invention is susceptible to various modifications. changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.
I. In a method for continuously dyeing a length of fabric by moving the fabric in the direction ofits length through a dye station where the fabric is impregnated with a quick setting dye, the improvement comprising imparting a longitudinal twist to the fabric ahead of the dye station to cause the fabric to pass through the station in a twisted state for causing the dye to nonuniformly color the fabric with a generally longitudinal. randomly varying pattern effect. and then storing the fabric. while maintaining it longitudinally twisted for at least the time required for the dye which has impreg nated the fabric to completely react.
2. A method as defined in claim 1 wherein the dye station includes a rotatable dye delivery cylinder and further comprising displacing the fabric, at a point ahead of the dye station. in a cyclic manner transverse to its length and parallel to the axis of such cylinder.
3. In a method for continuously dyeing a length of fabric by moving the fabric in the direction of its length through a dye station where the fabric is impregnated with a quick setting dye. the improvement comprising imparting a longitudinal twist to the fabric ahead of the dye station to cause the fabric to pass through the station in a twisted state for causing the dye to nonuniformly color the fabric with a generally longitudinal. randomly varying pattern effect, and manipulating the fabric ahead of the dye station for periodically varying the degree of compression of the twisted fabric transverse to its length and the configuration of the twisted fabric as it passes through the station.
4. A method as defined in claim 3 wherein said step of manipulating includes periodically varying the degree of twist of the fabric.
5. ln apparatus for continuously dyeing a length of fabric, which apparatus includes a dye station through which the fabric passes while travelling in the direction of its length and in which the fabric is brought into contact with a quick-setting dye in such a manner as to cause the dye to impregnate the fabric. the improvement comprising: means disposed ahead of said dye station and mounted for rotation for imparting a longitudinal twist to the fabric to cause the fabric to pass through the station in a twisted state for causing the dye to non-uniformly color the fabric with a generally longitudinal, randomly varying pattern effect; drive means connected to rotate said means for imparting a twist; and storage means for storing the fabric in its longitudinally twisted state after it has passed through said dye station.
6. In apparatus for continuously dyeing a length of fabric. which apparatus includes a dye station through which the fabric passes while travelling in the direction of its length and in which the fabric is brought into contact with a quick-setting dye in such a manner as to cause the dye to impregnate the fabric, the improvement comprising means ahead of said dye station for imparting a longitudinal twist to the fabric to cause the fabric to pass through the station in a twisted state for causing the dye to non-uniformly color the fabric with a generally longitudinal. randomly varying pattern effect. wherein said means for imparting a twist comprises a turntable arranged to receive such length of fabric in an initially untwisted state and to rotate as fabric is conveyed therefrom to said dye station.
7. Apparatus as defined in claim 6 wherein said turntable is oriented to rotate about a substantially vertical axis and said means for imparting a twist further comprises a circular guide hoop mounted for rotation with said turntable and oriented to lie in a plane inclined to the axis of rotation of said turntable, said hoop being arranged to permit the length of fabric to pass therethrough and bear against the surface thereof while trav eling from said turntable to said dye station.
8. Apparatus as defined in claim 7 further comprising: subsequent treating means disposed beyond said dye station; first guide means for continuously guiding such fabric from said dye station to said subsequent treating means. and second guide means disposed beyond said subsequent treating means for guiding the fabric leaving said treating means while maintaining a fixed spatial relation between said treating means and the portion of fabric extending from said treating means to said second guide means.
9. A dyed fabric produced by the method defined in