Process for space dyeing and texturing synthetic yarns

A process is provided for space dyeing synthetic yarn in which the synthetic yarn, such as polyester yarn, wound upon a yarn package, is first treated by immersing the ends of the package into a solution of at least one sublimatable ink, thereby dyeing the yarn located at the ends of the package but leaving the yarn at the center of the package undyed, and then at least two ends from at least two such packages are passed through otherwise conventional drawing and texturizing apparatus. Each yarn so fed is intermittently dyed and undyed along its length, the color strength near the dye boundaries being attenuated and muted due to sublimation of the inks and diffusion and migration of the dyes through the yarn ends and into the package. By utilizing at least two feed yarn packages in such process having significantly different diameters and different colored ends thereof, very highly random dyeing effects are achieved in a knitted or woven fabric produced from such yarns. Also provided are the new, space-dyed yarns produced by the aforesaid process and fabrics produced from such yarns.

BACKGROUND OF THE INVENTION 
This invention concerns space-dyeing of synthetic yarns. The term 
"space-dyeing" refers to a dyeing process whereby dye is applied 
intermittently along the length of yarn such that, when the yarn is woven 
or knitted into a fabric, a more or less random color pattern is produced 
in the fabric. 
In the past, there have been many attempts to provide space-dyed yarn by 
applying tints and dyes to one or both ends of a yarn package which, upon 
being woven or knitted into a fabric, yielded an intermittent color 
effect. These attempts to date have generally not provided dyed fabrics 
having commercially acceptable wet processing (wash fastness) 
characteristics. 
U.S. Pat. No. 4,097,232 discloses a process for treating yarn packages with 
dyes followed by introducing heated steam for a time sufficient to cause 
the dyes to partially penetrate the yarn package. This process involves 
treating yarn in package from with one or more dyes or dye acceptance 
modifiers to modify or dye the yarn fibers in a reproducible manner to 
provide repeating contiguous sections of yarn having desired 
characteristics. In a preferred process, a dye acceptance modifier in the 
form of a resist is infused into one or both of the ends of a yarn package 
and a heated fluid (steam) is then introduced under pressure at a 
temperature and for a time sufficient to cause the resist to at least 
partially penetrate the package and contact individual strands of yarn or 
fibers, and to set the resist. 
U.S. Pat. No. 3,986,235 discloses a process for producing space-dyed 
textile strands by a process of contacting each of the flat ends of a 
wound yarn package with a coloring agent, withdrawing the yarn from the 
yarn package, and rewinding the yarn in reverse order into a second yarn 
package having at least one substantially flat end, and then contacting 
each of the flat ends of the rewound yarn package with a color modifying 
agent, e.g. a dye. The colored yarn can then be withdrawn from the rewound 
yarn package and woven or tufted into a carpet, for example, and dyed, 
resulting in a carpet having random flecks of contrasting color therein. 
Copending United States Patent Application Ser. No. 946,607, filed in the 
name of Allen A. Wiggins, Jr., discloses a process in which partially 
oriented synthetic yarn such as partially oriented polyester yarn is fed 
continuously first to and through a bath of a liquid conditioning agent 
such as a sublimatable dye, then to a first heated roll and then to a 
second heated draw roll to draw the partially oriented yarn, then to a 
texturizer and then to a takeup roll, all in one continuous operation, to 
produce a conditioned and texturized yarn product possessing about 12% to 
about 30% latent shrinkage. Also provided is a process for dyeing undrawn, 
partially drawn or fully drawn synthetic yarns using sublimatable inks. A 
method of space-dyeing using a gravure-type roll applicator is also 
disclosed therein. 
The aforementioned references, either alone or in combination, do not 
disclose space dyeing of unoriented or partially oriented synthetic yarns, 
using a sublimatable ink dyeing agent, by a method of applying the 
sublimatable ink to at least one end of at least one yarn package and 
thereafter drawing and heating and texturizing the yarn to produce a 
space-dyed, textured yarn. Further, the references do not disclose a 
process for producing a highly random color pattern in a woven or knitted 
fabric by feeding, in a predetermined sequence, multiple ends of 
multicolored, space-dyed yarn packages produced by the process of this 
invention. Such process and the products produced thereby are the subject 
of the present invention. 
By way of definition, the following terms are used herein. The term 
"undrawn yarn" is used to designate synthetic yarn having no orientation 
of its molecules or, at most, only a small degree of orientation, which 
yarn has been drawn prior to processing according to this invention to a 
degree considerably less than two (2) times its as-spun undrawn length. 
The term "yarn package" means yarn wound upon a core by the yarn 
manufacturer, and rewinding upon a special dyeing package is unnecessary. 
The term "sublimatable ink" as used herein refers to inks made primarily 
for printing applications. Insofar as is known, they consist of disperse 
dyes ground to a very fine particle size, and suspended in a water 
solution with the aid of suitable dispersing agents. They are generally 
intended for use where the ink is first applied to a printing paper and 
then transferred to a fabric being dyed by means of sublimation of the 
pigment and transferral to the fabric in the vapor phase. To satisfy 
various applications, these inks are available commercially in three 
general energy levels. Energy level indicates the degree of heat required 
to vaporize the dye-stuff so that it will transfer to the medium being 
printed. The lower the energy level, the easier it is to transfer the ink. 
However, the lower energy inks may produce printings which are deficient 
in light and wash fastness. The high energy inks are more difficult to 
transfer but generally give printed fabrics having outstanding levels of 
light and wash fastness. 
Preferred dyes include dyes manufactured by Ault and Wiborg, Ltd., London, 
England, including: 
Aultran* Red F02 
Aultran Red F04 
Aultran Blue F56 
Aultran Blue F57 
Aultran Yellow F23 
Aultran Yellow F24 
Aultran Violet F62 
Aultran Black F81 
FNT *"Aultran" is a trademark of Ault and Wiborg 
It is believed that these dye pigments are sublimatable anthroquinone, azo 
and methine dyestuffs. 
SUMMARY OF THE INVENTION 
A process is provided for producing an intermittently dyed, textured, 
synthetic polymeric yarn comprising: 
(a) applying to at least one end of at least one package of synthetic 
polymeric yarn a solution of a sublimatable dye pigment, 
(b) drying the dyed yarn package, 
(c) withdrawing at least one end of the yarn from at least one package and 
directing the yarn end to and around a first rotating predraw roller and 
thence to and around a second rotating, heated draw roller rotating at a 
faster peripheral speed than the first roller to impart draw to the yarn, 
(d) feeding the dyed and drawn yarn to and through a texturizer, and 
(e) accumulating the dyed, drawn and texturized yarn on a takeup device. 
A multiplicity of yarn packages can be employed to produce a multiple ply, 
intermittently dyed, drawn and texturized yarn. 
In a preferred process, the multiple feed yarn packages have different 
diameters, thereby producing a multiple-ply, highly random, intermittently 
dyed, drawn and texturized yarn. 
The synthetic yarn utilized in the process of this invention is selected 
from the class consisting of polyester, polyamide, cellulose acetate, 
polyvinyl chloride, and polypropylene yarns, and polyester is preferred. 
Also provided is a process for producing an intermittently dyed synthetic 
polymeric yarn comprising applying to at least one end of a synthetic 
polymeric yarn package a solution of a sublimatable dye pigment and 
thereafter drying the dyed yarn and applying heat to the yarn to fix the 
dye thereto. 
The products produced by the aforesaid processes and fabrics made therefrom 
are also provided.

DETAILED DESCRIPTION OF THE INVENTION AND PREFERRED EMBODIMENTS WITH 
REFERENCE TO THE DRAWINGS 
A detailed description of the invention is most readily provided by 
referring to the drawings. The best mode for carrying out the process of 
this invention is described in detail in the Examples below. 
To prepare a yarn package for feeding to the draw/texturizing apparatus 
according to this invention, at least one end of the package is immersed 
in a solution of one of the aforementioned sublimatable inks. Typically, a 
yarn package will comprise yarn wound upon a two (2) inch diameter core to 
provide a package about eight (8) inches in diameter and about ten (10) 
inches in length, although these dimensions can vary considerably. The 
package can be immersed to any desired depth into the dye solution. 
Preferably, the dye is dissolved in water. Upon removal from the dye 
solution, the package is allowed to partially dry, preferably for 
twenty-four (24) hours, and then placed upon a creel for feeding to the 
draw/texturizing apparatus. 
Partially oriented feed yarn is preferred. 
The term "partially oriented" yarn as used herein means yarn which has been 
drawn from its as-spun undrawn condition to an extent of at least two (2) 
times its undrawn length. Such yarns are commercially available and sold, 
for example, by E. I. du Pont de Nemours and Co., Inc., under the product 
designation DACRON.RTM. polyester yarn.* This yarn is partially oriented 
by the manufacturer by drawing about 3X, i.e. from about 750 denier 
as-spun to about 250 denier as obtained commercially. While partially 
oriented yarn is preferred for use in the process of this invention, 
undrawn or highly drawn yarns may also be utilized. 
FNT *"DACRON" is a registered trademark of duPont. 
Unoriented, partially oriented and fully oriented synthetic yarns may be 
space-dyed by the process of this invention and texturized, if desired. 
Textured yarn is preferred. 
FIG. 1 schematically illustrates the passage of feed yarn fed from the 
pre-treated (dyed) packages through the draw/texturizing apparatus. Three 
(3) yarn ends 8a-c are withdrawn from three (3) pre-treated, dyed yarn 
packages 10a-c, respectively. One end of package 10a has been dyed brown, 
the other green. One end of package 10b has been dyed green, the other 
orange. One end of package 10c has been dyed brown, the other orange. 
These color combinations can be varied as desired. The three yarn ends are 
passed to creel 12 and through guiding eyelets 14a-c and thence through 
gathering eyelet 16. From eyelet 16, the three ply, three color yarn 
bundle enters the drawing apparatus which comprises a set of driven rolls 
18 feeding the yarn to heated predraw roller 20, the yarn passing around 
roll 20 a number of times, preferably 7-14 times, in order to thoroughly 
heat the yarn, and thence through the draw zone 22 to and around heated 
draw roll 24, the yarn also passing around roll 24 a number of times, 
preferably 14-21 times, in order to prevent slippage and to maintain the 
yarn at temperature. 
The predraw roll 20 and the draw roll 24 are heated by conventional means, 
not shown, for convenience. Such heating means can be internal electrical 
resistance heaters, for example. In processing 250 denier polyester yarn, 
for example, the predraw roll typically may be 51/2 inches in diameter, 
heated to a temperature of about 200.degree. F., rotating at 375-750 rpm, 
and has seven wraps of yarn. The draw roller 24 typically may be 51/2 
inches in diameter, heated to a temperature of about 425.degree. F., 
rotating at 600-1200 rpm, and has fourteen wraps of yarn. Such conditions 
would result in a draw ratio of 1.6, i.e. 250 denier yarn would be drawn 
down to 150 denier yarn. 
From the draw roll 24, the drawn yarn is fed to optional oil or finish 
applicator roll 26, and is driven into heated stuffer box crimping device 
30 in order to texturize (crimp) the yarn, and thence through optional air 
entangler 32 and finally to take-up roll 34. The rotational speed of 
take-up roll 34 is adjusted relative to the rotational speed of drive 
rolls 28 to provide a continuous accumulation of yarn in the crimping 
device 30. The chamber of device 30 is heated, thereby providing 
additional means for accomplishing heat fixation of the inks to the yarn. 
Preferably, the texturizer is of the stuffer box type, although any 
texturization process involving yarn deformation (crimping) under 
application of heat could be utilized. False twist texturizing, for 
example, is also contemplated. 
FIG. 2 and FIG. 3 illustrate various combinations of feed yarn packages 
which may be used to produce multi-colored space-dyed yarn which can be 
woven or knitted into fabrics having extremely highly random color 
patterns. 
In FIG. 2, column I indicates the same yarn package combination shown in 
FIG. 1 described previously. Package 10a is larger in diameter than 10b 
which, in turn, is larger than package 10c. Typically, package 10a will be 
eight (8) inches in diameter, 10b will be six (6) inches in diameter and 
10a will be four (4) inches in diameter. The inner core present in all 
packages is shown dotted in package 10a in FIG. 2. A large diameter 
package that is impregnated with ink at one end thereof will yield, on 
unwinding, relatively long sections of dyed yarn with relatively long 
sections of undyed yarn between the colored sections. A small diameter 
package, on the other hand, will yield shorter dyed lengths and shorter 
undyed lengths at higher frequency than the larger tube. 
When multiple yarn packages of different diameters are used in the process 
of this invention, a multiple-ply yarn bundle is produced having a highly 
random combination of dyed-undyed segments in components of the bundle. 
When such multiple yarn packages having different diameters are also dyed 
as indicated in FIG. 2 at the respective ends thereof, a yarn bundle 
having a tremendously complex, random space-dyed color combination is 
achieved which, when woven or knitted into a fabric, produces a heretofore 
unachievable, highly random color pattern. 
FIG. 2 specifically shows the feed yarn packages for making a 3-ply, 
3-color product. The packages 10a-c in column I represent the initial load 
on the creel impregnated at the ends with three (3) different colors as 
shown in FIG. 1. As yarn is withdrawn from the feed packages, all three 
tubes become smaller to the point where the smallest package 10c at the 
start is exhausted and must be replaced. During this time period, the 
largest package 10a and intermediate package 10b are reduced to smaller 
sizes as indicated by the arrows in FIG. 2, extending from column I to 
column II. At the point in time when the smallest package is exhausted, a 
large package having the same color sequence as the exhausted package is 
placed in the system and operation is continued. As the smallest tubes 
progressively become exhausted, they are replaced by large tubes as 
indicated by the arrows and columns III, IV and V. It can be seen that, as 
operation progresses, the feed column represented by column IV of FIG. 2 
is identical with column I and the process is cyclical. 
Variations in overall color effects exist within the yarn produced from 
packages in any individual column and between yarns produced from 
different columnar arrangements, but these variations are generally slight 
and tend to be masked by the complexity of the color pattern. The 
variations substantially disappear when a large number of the yarns are 
utilized in making a multiple-end product such as in warp knitting. Also, 
if a 6-ply yarn is produced, a feed system represented by a combination of 
columns I and II of FIG. 2 will yield a product having a greater degree of 
randomness in its color pattern having less variations in overall color 
effects. 
FIG. 3 illustrates a system of yarn feed packages to be used to produce a 
4-ply, 3-color yarn. FIG. 3 is similar to FIG. 2. It is to be noted that 
in this system, once the smallest package in column III is exhausted the 
feed system of column I is repeated. 
FIG. 4 is a photograph of a fabric knitted from a 3-ply, 1-color yarn 
produced according to the process shown in FIG. 1 and described 
hereinabove. The highly random nature of the color pattern in this fabric 
is evident. 
FIG. 5 is a second photograph of the fabric shown in FIG. 4 taken at a 
different location. 
In summary, a process is provided for space dyeing synthetic yarn in which 
the synthetic yarn, such as polyester yarn, wound upon a yarn package, is 
first dyed by immersing the ends of the package into a solution of at 
least one sublimatable ink, thereby dyeing the yarn located at the ends of 
the package but leaving the yarn at the center of the package undyed, and 
then at least two ends from at least two such packages are passed through 
otherwise conventional drawing and texturizing apparatus. Each yarn so fed 
is intermittently dyed and undyed along its length, the color strength 
near the dye boundaries being attenuated and muted due to sublimation of 
the inks and diffusion and migration of the dyes through the yarn ends and 
into the package. By utilizing at least two feed yarn packages in such 
process having significantly different diameters and different colored 
ends thereof, very highly random dyeing effects are achieved in a knitted 
or woven fabric product produced from such yarns. Also provided are new 
space-dyed yarns produced by the aforesaid process and fabrics produced 
from such yarns. 
The synthetic yarns suitable for use in this process include the yarns 
obtained by spinning or extrusion of polymers, copolymers, graft 
copolymers and mixtures thereof, including polyesters, polyamides, 
cellulose acetate, polyvinyl chloride, polypropylene and similar 
thermoplastic polymers. The process is especially suited for continuous 
dyeing, drawing and texturizing polyester yarns. 
While the invention has been described above and in the examples which 
follow in connection with certain specific details and embodiments, it 
will be clear to one skilled in the art that changes or modifications 
deviating from these specific embodiments may be made without deviating 
from the gist of this invention, and such changes and modifications are 
deemed to fall within the scope of the claims below. 
The examples which follow are intended to be illustrative of the process of 
this invention, but not to limit the scope of the invention in any way. 
EXAMPLE 1 
Three feed yarn packages having diameters of 8, 6, and 4 inches, 
respectively, were prepared for feeding to the drawing and texturizing 
apparatus shown in FIG. 1 as follows. Each end of each feed yarn package 
was immersed to a depth of two (2) inches in a dye solution comprising 10% 
by weight in water of a black, sublimatable ink pigment (product 
designation Black F81, produced by Ault and Wiborg, Ltd., London, 
England). The packages were immersed in the dye solution for 30 minutes 
and were then removed from the bath and drained and allowed to dry in 
ambient air for 24 hours. 
The yarn used in this example was supplied by E. I. duPont de Nemours and 
Co., Inc., and was partially oriented polyester yarn available 
commercially under the designation "DACRON" polyester yarn, 250/34, Type 
242T. 
The three (3) pretreated yarn packages were then placed on a supply creel, 
and one end from each package was fed to and through a gathering eyelet, 
thereby gathering the yarn into a three-ply single bundle, and this yarn 
was then passed through conventional drawing and texturizing apparatus as 
shown in FIG. 1. The yarn was so processed at a rate of 600 yards/minute 
fed to a FDJCH Model crimping machine (manufactured by Techniservice 
Corporation, Kennett Square, Pennsylvania). The draw ratio employed was 
1.67 and only the draw roll was internally heated, in this example to 
400.degree. F. The crimping chamber walls were maintained at 325.degree. 
F. From the crimper, the yarn passed through a conventional air entangling 
device and thence to a take-up roll. 
A highly randomly dyed 3-ply, 1-color yarn was thus produced which, when 
knitted into a fabric, produced a highly random color pattern similar to 
that shown in the photographs of FIGS. 4 and 5. 
EXAMPLE 2 
For this example, four (4) yarn packages of varying diameters were employed 
similar to the diagram shown in FIG. 3. The yarn was duPont partially 
oriented "DACRON" polyester, 250/34, Type 242T. The diameters of these 
packages initially were 8, 6, 4 and 3 inches, respectively. Each package 
was immersed to a depth of two (2) inches into ink solutions of the 
compositions shown in the table below to form the supply system shown in 
Column I of FIG. 3: 
______________________________________ 
Solution A, wt 
Solution B, wt 
Solution C, wt 
% based upon 
% based upon 
% based upon 
Dye* total wt of dye 
total wt of dye 
total wt of dye 
______________________________________ 
Yellow 
"F23" 35% 35% 50% 
Red 
"F02" 50% 0% 45% 
Blue 
"F56" 15% 55% 5% 
Black 
"F81" 0% 10% 0% 
Total ink 
concen- 
tration, 
wt % based 
upon total 
wt of solution 
7% 8% 8% 
______________________________________ 
*Available commercially from Ault and Wiborg, Ltd., London, England. 
Each package was dyed, drained and allowed to dry for a period of 24 hours. 
These packages were then mounted on a creel as shown in FIG. 1 and the 
ends of each were gathered into a bundle through an eyelet and the bundle 
was passed to the predraw roller which was a roller of 5.5 inch diameter 
maintained at 70.degree. C., the bundle passing 14 times around the 
predraw roller and thence passing to the draw roller maintained at 
225.degree. C. and passing 21 times around the draw roller, which imparted 
a draw of 1.67 X on the yarn bundle. 
From the draw roller, the yarn was passed into and through Model M-600 
Stuffer box crimping device (Techniservice Corporation). The yarn entered 
the crimper at a rate of 650 yards per minute. The walls of the 
accumulation chamber in the crimping device were maintained at 150.degree. 
C. Upon exit from the crimper, the yarn passed through an air entangler 
and thence was wound upon a takeup roll. 
The product yarn possessed highly random intermittent dyed and undyed 
sections. At points along the length of the yarn, one of the three 
principal colors was reinforced where two contiguous strands dyed that 
color happened to end up adjacent one another in the final product. At 
other points, there was a blending of two or all three of the colors, and 
at other points where dyed lengths were succeeded by undyed lengths, there 
was a gradual change from color to white. The color strength near the dye 
boundaries was attenuated and muted. 
A fabric was knitted using the product yarn so produced, and wash fastness 
tests were conducted. These tests yielded a 4 to 4.5 rating for an AATCC 
II-A cycle test and a 3.5 to 4 rating for an AATCC III-A wash cycle test. 
Thus, the fabric is suitable for upholstery and drapery applications and 
for some apparel uses. 
EXAMPLE 3 
Three yarn packages of duPont partially oriented "DACRON" polyester yarn, 
250/34, Type 242T each were impregnated at both ends by immersion to a 
depth of two (2) inches for 10 minutes in an aqueous solution of 3.3% by 
weight (based upon total solution weight) of "BLUE FW 59/1" sublimatable 
dye pigment (Ault and Wiborg, Ltd.). The diameters of the yarn packages 
were 8, 6 and 4 inches, respectively. The impregnated packages were 
drained and air dried for 24 hours and then drawn and texturized as in 
Example 2 except that in this example an FCJ Model stuffer box crimper 
(manufactured by Techniservice Corporation) was employed. This crimping 
device is suitable for fine yarns but is not as closely temperature 
controlled as the Model M-600 crimper. 
Yarn produced according to this example was knitted into a fabric and a 
highly random distribution of color patterns similar to that shown in FIG. 
4 was achieved. This fabric was subjected to wash fastness tests as in 
Example 2. These tests yielded a rating 3.5 to 4 in an AATCC II-A wash 
test and a rating of 3.0 to 3.5 in an AATCC III-A wash test. The product 
is, therefore, suitable for upholstery and drapery uses.