Note: Descriptions are shown in the official language in which they were submitted.
WOg3/16~24PCT~U~92/tO443
1- 2l`~!996~
MET~OD A~D APPARATUS ~OR DYEI~G CARPET
sAc~GRouND OF THE INVE~TION
Fiela of the Inve~tion
This invention relates to the dyeing of carpets
and, more particularly, ~o a method and apparatus for
dyeing carpets which, through the use of a dye bath which
has a much higher boiling point than water, does not
require the steaming o~ the carpet to set or fix the dye
10 to the carpet.
Prior Art
Currently known and used methods and apparatuses
for dyeing carpet require the steaming of the carpet to
set or fix the dye to the carpet after the dye has been
15 applied to the carpet. For e~ample, the typical carpet
dyeing method and apparatus involves the application of a
dye to the pile surface of the carpet, fixing the dye onto
the carpet pile by steaming and then subjecting the carpet
to ~arious other finishing procedures prior to drying the
20 carpet.
Once such conventional carpet dyeing process is
disclosed in V.S. Patent No. 4,101,270. This paten~
discl~ses a method for dyeing carpet which includes the
teps of advancing a continuous textile web through a
2S pre~hrinking station, moistening the te2tile web, dyei~g
the textile web using applicator rolls and~or dye
;~ applicators, and then fixing the dye onto the textile web
by passage through, for example, a chamber containin~
steam. This basic method generally forms the base for th~
30 other prior art carpet dyeing systems and is well known -in
the art.
Likewise, a second e2ample of a carpet dyeing
process including a steam fi2ator is disclosed in U.S.
Patent No. 4,771,4g7. This patent discloses a process for
35 the continuous treatment of a te~tile web material
W0~3/1622~ PCT/U~92/1~3
~ 12 9 g~U~ 2 -
involving the application of a dye to the pile surface of
the carpet and then initiating the dye fi~ation onto the
pile surface by steaming. Many of the prior art patents
such as the two disclosed above involve such a steam
5 fi~ation process and are distinguishable from each other
by various additional, optional processes added onto this
base dyeing technique.
The patent issued to Walter, U.S. Patent No.
2,387,200, discloses and claims a method for dyeing
10 material which is carried out in a sealed chamber, namely
a closed chamber incorporating compressed air and
saturated steam. The ~200 method is carried out at a
temperature substantially above 212F and under pressure.
Therefore, the '200 method incorporates by its nature a
15 steam figation step as when the material emerges from the
dye bath which is heated substantially above 212F, it
encounters co~pressed air and saturated steam under
pressure, which is the equivalent of a steam fi~ation
step. The apparatus of the present invention is not a
20 closed or sealed chamber, but is open to the atmosphere,
and does not use water-based dye baths or steam, thus
eliminating the steam fixation step which can cause uneven
dyeing and running of the dye. Further, the use of an
open chamber and lower overall temperatures, namely
25 typically between 212F and 2~0~F, allows the present
invention to be much more economical in terms of energy
costs and apparatus material costs.
The method disclosed in the '200 patent also does
not comprise a separate, independent material preheatin~
30 step, nor the means for carrying out such a separate,
independent material preheating step. The material to be
dyed in the '200 method is introduced to the pressure
chamber and almost immediately submerged into the dye
bath. Although the material to be dyed encounters
35 elevated temperatures upon being introduced to the
WO~3/162~4 PCT/US92/1~3
2 12 9 9 ~ S ~ '~
pressure chamber, no specific control or methodology is
present to constitute a preheating step or means. In the
present invention, a separate, independent preheating step
accomplished by a separate, independent preheating means
5 is carried out on the material to be dyed prior to the
introduction of the material to be dyed to the main dye
bath. The controlled preheating of the material to be
dyed to a temperature near or at the tempe~ature of the
dye bath helps to reduce the dye application time and the
10 heat loss from th~ dye bath which would occur if the
material to be dyed needed to be heated to the temperature
of the dye bath during the dyeing process. Such a
separate, independent preheating step and means, which may
utilize the same heat source as the dye bath, has economic
15 advantages over prior art processes, such as that
;~ disclosed in the '200 patent.
The patent to von der Eltz et al., U.SO Patent
No. 3,986,831, discloses and claims a high temperature,
high pressure batch process for dyeing materials which
20 incorporates a pressure vessel and high-pressure steam
fixation. The '831 apparatus and method operate in an
essentially air-free environment. Further, the dye
fi~ation dis~losed in the '831 patent occurs at a
temperature over about 255F, creating the need for
25 significant energy input. Likewise, the patent to Blount,
V.S. Patent No. 3,418,065, discloses and ~laims a high
temperature, h_gh pressure batch process which also is
carried out in a sealed pressure chamber not open to the
atmosphere and which incorporates a steam fixation step
30 On the c -~rary, the present process and apparatus are
open to t l'mosphere and do not involve the use of ste~
or steam ~ ition. The present process is a continuou
process which is carried out on a continuous-running
apparatus. Further, the entire process of the present
35 invention can occur at a temperature of between 212F and
WO93/16224 PCT/US92/1~3
212g960
~ 4 -
about 240F, significantl:y reducing the energy costs and
the apparatus costs.
The disadvantages of such prior art carpet dyeing
methods and apparatuses which incorporate steam fixation
5 components is the necessity for the steam fi~ation step.
Steam fi~ation has several disadvantages including the
need for a tremendous amount of energy required to heat
the steam, dilution of the dye as the steam condenses into
water and mi~es with the dye, and the cost of the
lQ equipment, both in material and time, needed to have a
steam fixation step in the carpet dyeing process. A
further disadvantage is that a carpet dyeing process
including a steam fixation step is uneconomical to operate
when dyeing small batches of carpet.
The development of the open-to-the-atmosphere
process and apparatus also allows for the dyeing of
materials at significantly lower energy costs and with a
higher degree of safety. Less energy is necessary as
there are no materials to be superheated and no pressure
20 needs to be created. Materials costs are reduced as
vessels open to the atmosphere typically do not need the
reinforcing required for a pressure vessel. Lastly,
pressure operations typically inherently are more
dangerous than an equivalent atmospheric operation.
SUMMARY OF THE I~VENTION
In accord with this invention, a more efficient,
less costly carpet dyeing method and apparatus is
disclosed. This invention may be used to dye carpets as
30 well as all types of yarns, fibers, woven fabrics, kni-ts
~;~ and other fabric type materials made from, for example,
nylon, polyester, wool, cotton, rayon and acrylics This
inv~ntion continuously dyes carpet without steaming by the
use of a high temperature dye bath, fed at a specific
35 temperature and flow rate to an applicator, in which the
WO93J16224 PCT~US92/1~M3
~ 5 ~ 2 1a 9 ~ 6~
level and the temperature of the dye are controlled.
This invention comprises a novel dye bath
applicator which effects the carpet dyeing and fixing step
by utilizing a high temperature dye mixture, the
5 temperatuxe of which is higher than the boiling point of
water. The apparatus of this invention is open to the
atmosphere and does not constitute a pressure vessel in
the sense disclosed in prior art dyeing apparatuses. By
eliminating the need for pressure vessel-type couplings
10 and materials, the apparatus of this invention is both
much less costly and safer to operate. The appara~us of
this invention also generally comprises a preheater which
effects the preheating step, a heated mix tank which
effects the heating step of the dye and chemicals, a heat
15 e~change{ which effects the step of heating the dye prior
to the dye entering the applicator a vacuum e~tractor
which effects the step of recovering the excess dye and
returning it to the heat exchanger, and wash boxes with
overflows which effect the step of neutralizing the pH of
20 the carpet and washing the carpet before the carpet enters
the drying stage.
This invention eliminates the need for a steam
f~ator by preheating the dye to a temperature above the
boiling point of water and applying it to a preheated
25 te~tile web. A unique mi~ture of chemicals allows the dye
; to be heated above the boiling point of water in this
invention such that the dye is fixed onto the carpet pile
during the dyeing step, therefore eliminating the need for
a steam fixator after the dye application step.
There are numerous advantages to the novel met-hod
and apparatus of this invention. Some of these advantage~
include the elimination of any steam necessary in the dye
fixation process, the elimination of the need for gum or
thickeners, the elimination of the need for defoamers, and
35 the reduction in the amount of pollutants emanating from
WO93/16224 PCT/US92/1~3
~ ~ 6 -
the system. Other advantages include ~he elimination of
dye or chemical waste, no increase in chemical and
dyestuff content, and the need for less water usage in the
system, which water can be recycled. Further advantages
5 of this invention include a more uniform dye application
to the carpet from the side to the center to the side of
the carpet, better carpet definition, a less expensive dye
machine, and the need for less dye space for the dye
applicator.
Many conventional dye applicators or machines can
be converted inexpensively to the method and apparatus of
the present invention. Additionally, the method and
apparatus of the present invention can dye a single strand
of carpet yarn or a twelve foot (12') wide piece of carpet
15 or wider, or any carpet size in-between, in a level
configuration. It also is economical to dye small dye
; lots in the present invention as the dye beck time is
~ reduced significantly compared to the prior art.
- Furthermore, the preheater used in this invention is
20 heated from the heating system used to heat the dye bath
applicator, thus saving significantly on heating costs
throughout the system.
Accordingly, it is an object of the present
invention to provide a carpet dyeing method and apparatus~
25 which eliminates the need for a steam fixation apparatus
and step.
It is another object of the present invention to
provide a carpet dyeing method and apparatus which has
lower costs than conventional carpet dyeing methods anc1
30 apparatuses, including lower power costs, lower machine
costs, lower materials costs, and lower operating cnsts.
It is a further object of the present invention
to provide a carpet dyeing method and apparatus which
eliminates the need for gums, thickeners, and defoamers.
It i5 yet another object of the present invention
WO93/16224 PCT/US~ 3
to provide a carpet dyeing method and apparatus which has
no dye or chemical wastes and has no increase in chemical
and dyestuff content.
It is still another object of the present
5 invention to provide a carpet dyeing method and apparatus
which gives a more uniform dye application from side to
center to side and which gives better carpet definition.
It is a still further object of the present
invention to provide a carpet dyeing method and apparatus
10 which utili~es a less expensive dye machine, takes up less
floor space for the dye applicator and uses less water and
recycles the water which it uses.
It is another object of the present inven~ion to
provide a carpet dyeing method and apparatus which can dye
15 a single strand of carpet yarn all the way up to a twelve
foot (12'~ wide or wider piece of carpet and which is
economical to operate when dyeing small dye lots.
It is yet another object of the present invention
to provide a carpet dyeing method and apparatus in which
20 the preheater is heated from the heater unit used to heat
the dye bath appli~ator.
It is also an object of the present invention to
provide a unique dye solution which can be heated above
the boiling point of water and can be figed to a te~tile
~; 25 web without the need for steam fi~ation.
These and other objects of the invention will
become apparent to those skilled in the art upon reading
the following detailed description of the invention taken
in conjunction with the following drawing in which like
30 characters of reference correspond to like parts.
BRIEF DESSRIPTION OF THE DRAWI~G
Fig. 1 is a schematic of the method and apparatus
of the present apparatus.
WO93/16224 PCT/US92/1~3
21`~9~1~0 ~ 8 - `
DETAILED DESCRIPTION OF A PR~FERK~D EM~ODIME~T
A general schematic of the method and apparatus
of the present invention showing the various components
necessary to carry out this method is shown in Fig. l. In
5 general, this invention, using a novel dye solution
comprising dye, various chemicals as dye assistants and
water, utilizes a dye solution which has a much higher
boiling point than water. This higher boiling point dye
solution is used as a bath to dye carpet. This bath is
l0 the main aspect that makes this invention unique from
conventional methods of dyeing carpet. The term carpet is
used in this disclosure to cover all fabrics, yarns and
textile webs and is not meant to be limited to
conventional carpeting as known in the art.
15In this invention, carpet is colored by the dye
in the higher boiling point bath. The higber boiling
; point dye bath allows the dye to be fixed to the carpet at
that step, thus eliminating the need for a steam fi~ator.
Additionally, the higher boiling point bath is heated in a
20 novel and unique way as compared to the method for heating
conventional dye baths. For example, the bath is heated
by electric coils or elements or, alternatively, wîth an
enclosed steam system to a temperature greater than the
bo;ling point of water, a temperature which cannot be
ZS obtained in conventional systems. The method of heating
~j:
also provides a more direct heat source.
The presence of a steam fixator causes a dilution
of the dye solution. Therefore, the elimination of the
steam fixation step also is important to the inventiol-
30 because the dye solution contains a given concentration ofdye, chemicals, and water and any dilution of this
solution may affect both the coloring of the carpet and
the ability of the dye to be heated above the boiling
point of water. As the carpet leaves the dye bath, the
3~ carpet is squeezed to remove excess dye, which dye is
:::
~::
WO93/16224 PCT/US92/1~3
9 21~60 ~
recycled to the dye bath. Then the carpet enters a cold
water bath in which the dyeing process is stopped or
fixed. Once the dye is fixed, normal variations in color
in the carpet from side to center to side do not occur, as
5 is common in continuous dyeing with a s.team fixation
step. ~he carpet is then rinsed in one or more wash boxes
with overflow.
Referring now to Fig. 1, the dye solution
utilized in this invention is stored in a dye vat 26. The
10 dye solution utilized in this invention is a unique
mixture of specific dyes, chemicals and water. In
general, dye solutions are formed by dissolving dyes in a
portion of the water to be used in the dye bath 18.
Dyeing assistants and an acid to control the pH of the dye
15 solution then are dissolved in t.he balance of the water to
be used in the dye bath 18. ~,he dissolved dye and the
~: dyeing assistants and acid then are combined and mixed
.
with a quantity o~ glycol. The glycol increases the
. boi~ing point of the dye solution to a temperature above
20 the boiling point of water. This dye solution is heated
to a temperature just below the boiling point ~f the dye
solution, which, due to the mixture of components in the
dye solution, is higher than the boiling point of water~
and is applied to the carpe~ 10 in the dye bath applicator
25 unit 17, as d~scribed more fully below.
Many mi~tures of dye, chemicals and water may be
made depending upon the dye desired. Useful dyes include,
for example, acid dyes, disperse dyes, direct dyes, basic
dyes, vats dyes, fiber reactive dyes, and any other dy!es
30 that can be applied hot to a substrate. Two examples of
~ representative dye solutions are as follows:
:
WO93/16224 PCT/US92/1~3
2129960 f
~.. , 3'~ ~r - lO
E~LE 1
ComPone~t Percent bY W~i~ht Grams/Lite
S Dyes (selected acid dyes) XX.X X.XX
Benzyl ~lcohol (747-Alcohol,
DEG Glycol, Anonic and Nonic
Surfactant) 0.2 2.00
Fulgen SDM (Etho~ylated C12-C15
Primary Alcohol and Coconut
Condensate) 0.2 2.00
15 Sulfamic Acid, 15% sol. 1.0 10.00
Water 23.5 31~.00
Subtotal of Dye 2~.0% 330.00
Diethylene Glycol (sp.
gr. 1.12) or other types
of Glycol 75.0 670.0Q
25 TOTAL 100.0% 1000.00
As described above, the selected acid dyes are
first dissolved in a portion of the 316.00 g ~or 316 ml)
of water great enough to allow for the dissolution of the
30 dyes. The dyeing assistants, such as benzyl alcohol and
~ulgen SDM, and an acid to control pH, such as sulfamic
acid, are then added to the dye/water mixture. These then
~ ,
are combined and mi~ed with the diethylene glycol or other
glycol, which previously has been mi~ed with the remainder
35 of the 316.00 g of water, to form the dye solution. The
boiling point of this specific dye solution is
approximately 228-230F. This specific dye solution is
particularly useful for nylon tufted carpet or other nylon
abrics.
'~
WO93/16224 PCT/US92/1~3
212g960
E~MPLE 2
ComponentsPer~ent by Weiaht Grams/Lite
r
5 Dyes XX.X X.X
Fulpon GP (Potassium Salt
of Etho~ylated Phosphate
Alcohol)(Phosphated DA-43 0.2 ~.0
Water 10.0 130.0
Fulpal ME Anionic Surfactant
(P-NP-9) 0 5 5.0
Sulfamic Acid, 15% sol. 0.5 5.0
Water 1~.8 188.0
20 Subtotal of Dye 25.0~ 330.0
Diethylene Glycol or other
~ ~lycol ~5.0 -~70-Q
:: 25 TOTA~ 100.0% 1000.0
As in E~ample 1, the dye first is dissolved in a
: portion of the water great enough to allow for the
dissolution of the dye. The water for this specific dye
;~ 30 should be hot and a dispersing agent, such as the Fulpon
P,~ generally is needed to assist in complete
di~solution. A leveling agent, such as Fulpal ME, and an
acid to control the pH, such as sulfamic acid, is then
added to the dye/water mixture. This solution is combined
.
3~ and mixed with a glycol, which pre~iously has been mi~ed
with the remainder of the water, to increase the boiling
point of the dye solution. The boiling point of this
specific dye solution also is approximately 228-230F.
This specific dye solution is particularly useful for
40 polyester carpet or other fabrics.
Any glycol which allsws heat transfer is suitable
for the dye solution. The appropriate dying assistants
are selected so as to complement the fiber being dyed.
WO93/16224 PCT/US9?/1~3
2 1 2 9 a ~ 12
That is, certain fibers dye better when certain dyeing
assistants are used, as is known in the art. Anionic,
nonionic, cationic, wetters, levelers, and retarders are
all suitable dyeing assistants which are chosen according
5 to the fiber being dyed. Although most any acid is
appropriate to add to the dye solution, the most suitable
acids include formic, sulfamic, citric, acetic and
phosphoric, as well as acid generators.
The carpet, indicated generally by carpet roll
10 10, first enters a preheater 14 before it enters the dye
bath applicator unit 17. The preheater 1~, which
generally is an extension of the dye bath applicator unit
17, generally comprises an entrance door 12, a preheating
chamber 13 and transport rollers 16. The entrance door 12
15 generally is a spring loaded door, or a door with one way
hinges, opening toward the interior chamber 13 of the
~ ~ :
prehea~er so as to minimize heat loss from the preheating
chamber 13 through the door 12 into the atmosphere. The
; preheater 14, as well as the entire dye bath applicator
20 unit 17, is open to the atmosphere. Door 12, being a
~ spring loaded door, and e~it rollers 34, to keep the
-~ carpet 10 travelling through the apparatus, do not create
a pressure seal. Additionally, the dye bath applicator
, . .
unit 17 is not enclosed in a pressure vessel, as are
~; 25 current carpet dyeing apparatuses. The carpet 10 is
supported by roller 16 as the carpet 10 travels through
the preheater 14. The purpose of roller 16 is to support
and spread the ~arpet 10 as it enters the dye bath
applicator unit 17, in order to avoid wrinkles in the
30 carpet 10 and to prevent uneven dyeing.
The purpose of the preheater 14 is to heat the
carpet 10 prior to the carpet 10 entering the dye bath
applicator unit 17. Preheating of the carpet 10 keeps the
dye bath 18 from cooling down and helps open dye sites on
; 35 the carpet 10 so that the carpet 10 will be ready to take
WO93/16224 PCT/US92/1~3
'''''''"`' ` 212gaC~
the dye from the dye bath applicatvrs 19. The preheater
14 and preheating chamber 13 are heated using the same
heating system 30 that heats the dye bath applicator unit
17. The heat system 30 may be any conventional heat
5 system, such as electric coils or enclosed -steam. The
preheater 14 heats the carpet 10 to any selected
temperature up to about 220F.
The carpet 10 exits the preheater 14 and enters
the dye bath applicator unit 17. The dye bath applicator
10 unit 17 generally comprises dye bath 18, dye applicators
l9a, l9b, lgc, dye entrance ports 22, squeeze rollers 32,
and exit rollers 34.
The dye solution is supplied to the dye bath
applicator unit 17 through dye solution entrance ports
15 22. The dye solution, upon leaving dye vat 26, is
introduced through feedline 28 to a heat exchanger 20.
~: : The heat exchanger 20, which can be any conventional heat
~; : e~changer.unit, is used to heat the dye solution to a high
temperature, generally to any temperature up to about
0 24gF, prior to the dye solution entering the dye bath 18
: and the dye bath applicators l9a, l9b, l9c. A flow meter
(not shown) is located between the heat e~changer 20 and
the dye bath application unit 17 so as to regulate the
flow of the dye solution to the dye bath 18 so as to keep
the level o~ the dye bath 18 constant.
In the dye bath applicator unit 17, the carpet 10
passes through high temperature dye bath applicators l9a,
l9b, l9c which apply the dye solution to the carpet 10.
~ .
:~ : In~the dye bath applicator unit 17, the dye is furthel
30 heated to between about 160F and about 240F. The carpet
and the dye bath applicators l9a, l9b, l9c are
~: submerged within the dye bath 18 facilitating in the even
application of the dye to the carpet 10. The carpet 10 is
~; threaded under first applicator roller l9a, over ~econd
:: 35 applicator roller l9b, and over third applicator roller
WO93/16224 PCT/USg2/1~3
.
~ 1 2 9 9~ 14
l9c to ensure even and thorough dye application. In the
dye bath application unit 17, the carpet 10 is submerged
in the dye bath 18 as it passes under, over~ and under the
applicator rollers, l9a, l9b, l9c, respectively.
After the dye solution has been applied to the
carpet 10, the carpet 10 leaves the dye bath 18 and passes
through squeeze rollers 32 to remove excess dye solution.
The squeeze rvllers 32 are located above the dye bath 18
such that any excess dye solution squeezed from the carpet
10 10 falls back into the dye bath 18 in a recycle fashion.
After having the excess dye solution squeezed from the
carpet 10 by the squeeze rollers 32, the dyed carpet exits
the dye bath applicator unit 17 through exit rollers 34
which serve to remove some excess dye solution and to
1~ prevent heat loss from the dye bath applicator unit 17.
Squeeze rvllers 32 function to remove e~cess dye from the
dyed carpet 10 and are located within the extended dye
bath applicator unit 17. E~it rollers 34 typical~y are
constantly moving rollers which function to keep the
20 carpet 10 moving continuously at a desired rate through
the apparatus such that the method can be carried out.
The nature of the rollers 34 and the carpet 10 is such
that this type of roller 34 does not squeeze the carpet 10
to such an extent so as to create a pressure seal within
25 the e~tended dye bath applicator unit 17.
As any width of carpet 10 may be dyed in the
present apparatus using the present method, and rollers 34
are constant width, there typically will be space between
the edges of the carpet 10 and the edges of the rollers 3~
30 such that the dye bath applicator unit 17 is open to the
atmosphere via these and other spaces. Thus, pressure
build-up within the dye bath applicator unit 17 is
prevented.
The dyed carpet 10, which may still contain
35 excess dye solution from the dye application process, next
WO93/1~24 PCT/US92/1~3
- 15 - 2129~ t,~
passes through a vacuum extractor 36. The vacuum
e~tractor 36 is a conventional unit which further removes
excess dye solution from the dyed carpet lO through a
vacuum means. Any excess dye solution removed from the
5 carpet lO by the vacuum extractor 36 is returned to the
heat e~changer 20 through recycle line 38. The e~cess dye
solution, therefore, is recycled back to the dy~ bath
applicator unit 17 for dyeing further carpet.
The dyed carpet passes from the vacuum extractor
lO 36 to one or more wash boxes 40. The purpose of wash box
40 is to wash off excess dye solution and chemicals, and
to clean the carpet f rom any other debris which may have
been picked up during the dyeing process. The wash box 40
uses a cold water bath with a neutral pH for the cleaning
15 purpose. A further ef~ect of the cold water bath is to
aid in halting the dyeing process and to aid in fi~ing the
dye on the carpet lO surface.
In operation, the carpet lO travels between one
or more rollers 44 in the wash box 40 to increase the
20 amount of time the carpet is in the cold water bath. Upon
leaving the wash box 40, the carpet lO passes by a spray
washer 46 which also acts as the water introduction unit
to the wash box 40. After ~eing sprayed wi~h cold water
by the spray wash 46, the carpet lO passes through squeeze
5 rollers 48 to remove e~cess water. In some applications,
it is advantageous to have a plurality of wash boxes 40
which generally are identical with each other. Each wash
box 40 also is equipped with an overflow 42 to maintain a
~; constant level of water in the wash bax 40. After leaving
30 the wash bo~ 40, the carpet lO is dried in a convention-a~
manner, using conventional carpet drying apparatus.
The above process when applied with the
appriopriate apparatus will dye nylon, polyester, cotton,
wool and other fibers utilizing acid, disperse, direct and
35 basic class dyestufs. The above process when utilized
WO93/16224 PCT/US92/1~3
2 1 29 ~ ~ 16 -
with the appropriate apparatus also accomplishes currently
acceptable fastness and crocking performance levels with
no steamer unit or other steam requirement for
satisfactory color setting. Furthermore, the process of
5 this invention when utilized with the appropriate
apparatus achieves near 100% exhaustion of the dye
solution and reduces affluent waste in the dye process by
approximately 75% and is applicable to certain existing
equipment upon modification of that equipment. When the
10 carpet 10 comes out of the dye bath 18, the color shade is
fully developed and will not continue to build in color
department. Further, the water used in the wash box 40
can be recycled with simple plumbing additions (not shown).
The apparatus of the present invention can be
15 retrofitted to most e~isting carpet dyeing equipment of
the continuous range variety. The primary change would be
to install the dye bath applicator 17 in line with the
existing eguipment. The existing steamer can be removed
from the existing equipment as it is no longer needed, and
20 the dye bath applicator 17 may be installed in its place.
:~ Alternatively, the dye bath applicator 17 may be placed
~ immediately before the e~isting steamer with the carpet 10
-~ first traveling through the dye bath applicator 17, then
through the existing steamer, then to the carpet washing
25 system. If this alternative is utilized, the existing
s~eamer need not be turned on as it is unnecessary.
Likewise, the dye bath applica~or 17 may be placed
immediately after the e~isting steamer with similar
results.
This invention can be applied to all continuous
dye ranges for carpet dyeing and to all forms of yarn
dyeing such as, for e~ample, warp, skein and knit-deknit
space dyeing~ This invention produces superior side to
side color matching on continuous dye ranges and produces
35 improved tuft definition and hand in saxony and velvet cut
W093/16224 PCT/U~92/1~3
. ~ ~
` - l7 - 2 1 2 9 g 6 ~ ~
pile constructions. Furthermore, this invention has no
practical limitation on speed other than the equipment
speed limitations. Carpet dyed by the present process and
apparatus displays superior color characteristics when
5 compared to carpets dyed by conventional dy-e becks and
continuous ranges.
It will be obvious to those skilled in the art
that many variations may be made in the embodiment chosen
for the purpose of illustrating the best mode of this
lO invention without departing from the scope thereof as
defined by the appended claims.
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