Note: Descriptions are shown in the official language in which they were submitted.
~L:;2S~7S3
I FIELD OF THE INVENTION
The present invention relates ko the dyeing of dyeable mate-
rials and, more particularly, it relates to a method of signifi-
cantly reducing degradation of the dyestuff used in non-aqueous
high temperature dyeing processes.
BACKGROUND OF THE INVENTION
The dyeing of dyeable materials, especially synthetic mate-
rials such as polyester, has previously been conducted with a
dyestuff dispersed in an aqueous bath. The dyeable material is
placed in the bath for a long enough time period to allow dye-
stuff to be absorbed to provide the desired coloration.
Such a dyeing process poses several disadvantages and limi-
tations. Since the temperature of the aqueous bath cannot exceed
the boiling temperature of the water, the process cannot b~ con-
lS ducted at elevated temperatures unless high pressura is used.
Even then, temperatures of only 250F to 270F are reached. Con-
sequently, relatively long dyeing cycles are needed.
Additionally, the aqueous bath is generally disposed of
after each dyeing cycle because most of the dyestuff has been
ab~orbed by the dyeable material. The disposal of the used dye
~bath presents obvious environmental problems, as well as economic
losses due to discharge of the residual dyestuff and chemicals
remaining in the bath.
Dyeing at elevated temperatures with a non-aqueous system
overcomas many of these problems and provides several advantages.
Elevated temperatures reduce the time needed to dye the dyeable
material. Shorter dyeing cycles make the process more economical
and efficient.
`~ ~Z~875;~
Various dyeing processes that use non-aqueous dye
compositions have been proposed for the treatment of
dyeable materials. One technique involves immersing the
dyeable material in a bath comprising an organic
dyestuff dissolved in a high boiling aromatic ester or a
cycloaliphatic diester. Such dyeing processes provide
several disadvantages that prevent their effective and
efficient use. The dye composition does not remain
stable over a period of time when used in an ambient
atmosphere and significant degradation of the dye
composition often occurs after only a few hours of use.
It was initially believed that the stability
problem could be eliminated by varying the chemical
properties or components of the dye composition. Thus,
in an attempt to solve the problem, the diester
component was replaced by a modified diester, i.e., an
adduct of terephthalic acid. Although this dye
composition increased stability, significant degradation
still occurred and satisfactory dyeing was not obtained.
These poor results were especially prevalent when the
dye composition was applied by spraying which exposes
the largest liquid surface area to the atmosphere.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention
to provide a non-aqueous process for the dyeing of
dyeable materials at an elevated temperature in which
the dyestuff does not undergo significant degradation.
It is a further object to provide a non-aqueous
dyeing process at an elevated temperature that allows
for the recycling of the dye composition without
significant degradation of the dye-stuff.
.~
`::
~2587~;3
It is also an object to provide a proce~s or the non-aque-
ous dyeing of dyeable materials at an elevated temperature in
which the various steps, such as preparation of the dye composi-
tion, preheating, dyeing, cooling, rinsing, and drying, are con-
ducted in the same non-reactive environment.
Additional objects and advantages of the invention will be
set forth in part in the description that follows and in part
will be obvious from the description, or may be learned by prac-
tice of the invention.- The objects and advantages of the inven-
10 tion may be realized and obtained by means of instrumentalitie3
and combinations particularly pointed out in the appended ciaims.
To achieve these and other objectives, the present invention
provides a non-aqueous process for the dyeing of a dyeable mate-
rial at an elevated temperature, the improvement comprising the
15 step of contacting a dyeable material with a dye composition at
an elevated temperature in a non-reactive environment, the dye
composition temperature and the time of contact between the dye
composition and the dyeable material being sufficient to effectu-
ate the dyeing of the dyeable material, the dye composition com-
20 prising a substantially non-aqueous solvent and a dyestuff.
The present invention further provides a non-aqueous process
for the dyeing of a dyeable material at an elevated temperature
comprising the step~ of: preheating the dyeable material; con-
tacting the preheated dyeable material with a dye composition at
25 an elevated temperature in a non-reactive environment, the dye
composition temperature and the time of contact between the dye
composition and the dyeable material being sufficient to effectu-
ate the dyeing of the dyeable material, the dye composition com-
pri~ing a substantially non-aqueous solvent and a dyestuff, the
~L:258753
non-reacti~e environment being selected from the group consisting
of fluorocarbons and halogenated hydrocarbons; and cooling the
dyed dyeable material.
The dye composition preferably utili~es a solvent having a
boiling point greater than water. In a preferred embodiment, the
solvent is at least one of an aromatic ester and a cycloaliphatic
diester. The preferred fluorocarbon is 1,1,2-trichloro-1,2,2-
trifluoroethane, which has the chemical formula CC12FCClF2. The
preferred halogenated.hydrocarbon is l,l,l,trichloroethane
(methyl chloroform), which has the chemical formula CH3CC13. The
term dyestuff collectively refers to all of the individual dye-
stuffs that are present in the dye composition to obtain the de-
sired coloration of the dyeable material.
The process of the present invention obviates the problem of
dye composition degradation by providing and maintaining a non-
reactive environment, such as a fluorocarbon or a halogenated hy-
drocarbon, during the time the dyeable material is being con-
tacted with the dye composition. This non-reactive environment
prevents the dye composition from undergoing degradation. As
used herein, the term degradation refers to the loss of color-
~ation or color strength of the dyestuff in the dye composition.
The process further allows the dyeing process to be con-
ducted at an elevated temperature, since the solvent preferably
has a boiling point greater than water. As a result of the ele-
vated dyeing temperature, the dyeing process can be carried out
in less time than with aqueous dyeing processes.
Since degradation of the dyestuff ha~ been significantly re-
duced, the process permits the recycling of the dye composition
without adversely affecting the quality of the dyed product.
~:Z S87~3
Environmental and economic benefits are provided, because the
used composition i9 not discharged into the environment.
As used herein, the term dyeable material is defined as any
material that is capable of being dyed. The dyeable material can
be either a textile material or a non-textile material, such as
plastic. When the dyeable material is a textile material, for
example a garment such as a shirt, a skirt, or a pair of pants
made from a synthetic material such as polyester, the present
process also allows for the simultaneous shaping and setting of
the dyeable material, while the material is being dyed. The
shaping and setting of the garment provides creases, i~ desired,
and smooths out any wrinkles.
The foregoing and other objects, features, and advantages of
the present invention will be made more apparent from the follow-
lS ing description of the preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWING_
The accompanying drawings which are incorporated in and
constitutes a part of the specification, illustrate one embodi-
ment of the invention and, together with the description, serve
to explain the principles of the invention.
Figure 1 is a schematic diagram depicting the apparatus of
the present invention.
Figure 2 is a plan view of the apparatu~ of Fig. 1.
Figure 3 is a plan view of the interior of the apparatus of
Fig. 1 slowing a plurality of treatmen~ chambers.
Figure 4 is a more detailed schematic diagram of the loading
and unloading worX station of Fig. 1.
Figure 5 is a front view of the preheating and drying work
stations of Fig. 1.
~258753
Figure 6 i9 a side view of the preheatiny and drying work
stations shown in Fig. S.
Figure 7 is a more detailed schematic diagram of the dyeing
work station of Fig. 1.
S Figure 8 is a front view of the dyeing work station of
Fig. 1.
Figure 9 is a side view of the dyeing work ~tation shown in
Fig. 8.
Figure 10 is a sChematic diagram showing the contacting of a
dyeable material with a thin continuous film of the dye composi-
tion in the dyeing station of the apparatus in Fig. 1.
Figure 11 ls a schematic diagram showing the passage of the
non-reactive environment gas through the dyeable material in any
one of the preheating, cooliny, and drying stations.
lS Figure 12 is a more detailed schematic diagram of the rins-
ing work station of Fig. 1.
Figure 13 is a plan view of an applicator head used ln the
assembly shown in Figs. 7, 8, and 12.
Figure 14 is a cross section of the applicator head in
Figure 13 taken along line 14-14 thereof.
Figure 15 is a top perspective view of a carrier and dye
composition distribution head used in the present invention.
Figure 16 is a front view of the carrier and dye composition
distribution head shown in Fig. lS.
Figure 17 is a schematic diagram of the means used to rotate
the carousel unit of Fig. 1.
7~;3
DESC~IPTION OF THE PREFER~E~ EMBODIMENT
In a preferred embodiment o this invention, a non-aqueous
process for the dyeing of a dyeable material at an elevated tem-
perature is provided. In the process, a dyea~le material is con-
tacted with a dye composition at an elevated temperature in a
non-reactive environment. The dye composition temperature and
the time of contact between the dye composition and the dyeable
material are sufficient to effectuate the dyeing of the dyeable
material. As used herein, the dye composition comprises a sub-
stantially non-aqueous solvent, a dyestuff, and, if needed, one
or more additives. Preferably, the solvent contains no water,
but some water may be present.
In the present invention, the term non-reactive environment
is defined as any composition that can be maintained as a stable
gas at the dyeing temperature, without reacting with the dye com-
position or the dyeable material, and that will displace the air
and, therefore, the oxygen surrounding the dyeable material and
dye composition. Compounds that can be used as a non-reactive
environment include fluorocarbons; halogenated hydrocarbons
inert gases such as argon, neon, and helium; low boiling alcohols
and organic solvents, nitrogen, carbon dioxides and combinations
thereo. Fluorocarbons or halogenated hydrocarbons are the pre-
ferred compounds. The non-reactive environment preferably should
have a boiling point belo~ the temperature of the dyeing step but
above the temperature of the rinse step. This permits use of the
compound forming the environment aq a gas in the dyeing step and
a liquid in the rinse step.
Fluorocarbon solvents are relatively easy to maintain in a
vapor state; fairly safe for human e~pQ~ure; and unlikely to
~L2$87~3
break down into acid components. Moreover, they can be easily
separated from the dye composition by distillation. This permits
the recycle of both components. An especially effective fluoro-
carbon is 1,1,2-trichloro-1,2,2-trifluoroethane, which has the
chemical formula CC12FCClF2 and is sold by E.I. Dupont de Nemours
and Company under the trademark "Freon TF." Freon is a trademark
of the E.I. DuPont de Nemours and Company for fluorocarbon sol-
vents. Freon TF has a molecular weight of 187.39, a boiling
point of 117.63F, and a freezing point of -31 F. It is
nonflammable and has a threshold limit value (T.L.V.) of 1000
ppm.
A preferred halogenated hydrocarbon is l,l,l,trichloroethane
(methyl chloroform), which has the chemical formula CH3CC13, a
molecular weight of 133.42, a boiling range of 162F to 190F,
and a freezing point of -58.0F. It is nonflammable and has a
threshold limit value (T.L.V.) of 350 ppm.
The solvent used in the dye composition preferably has a
boiling point greater than water and can be one of the aromatic
esters and the cycloaliphatic diesters disclosed in U.S. patent
No. 4,293,305 in the name of Robert B. Wilson.
More specifically, the aromatic ester can be of the formula
ArCOOR2, ArCOO-Rl-OOCAr or (ArCOO)z-R3, whexein Rl is alkylene of
2-8 carbon atoms or polyoxyalkylene of the formula -CrH2r(OCrH2r)s,
in which r is 2 or 3 and s is up to 15; R2 is substituted or unsub-
stituted alXyl or alkenyl of 8-30 carbon atoms; R3 is the residue
of a polyhydric alcohol having z hydroxyl groups; Ar is mono- or
bicyclic aryl of up to 15 carbon atoms and z is 3-6.
F _~_
~2~i~753
The cycloaliphatic diester can be of the formula:
n C6H13 _~ ~ ~ ~ (CH2)7COGR
COo:~
wherein R is substituted or unsubstituted straight or
branched chain alkyl of 4-20 carbon atoms,
polyoxyalkylene of the formula R~(CXH2x)n or
phosphated polyoxyalkylene of the formula
(HO)2p(=O) (CXHZx)ncxH2x~
or a salt thereof, wherein (CxH2xO)n is (C2H4)n~~
(C3~6)n~ or (~2H40~p-, (C3H60)q~; R' is H or ArCO; Ar
is mono- or bicyclic aryl of up to 15 carbon atoms; x is
2 or 3; n is 2-22 and the sum of p + q is n.
Other solvents include glycerides, such as
vegetable oils of which corn oil, peanut oil, and blends
thereof are examples, and fatty acids.
The dyestuffs can be those commonly found in the
art, such as disperse, vat, reactive, direct, acid,
basic, sulfur, and pigment. The additives can be any of
those known in the art, such as levelers, dye carriers,
and organic finishing agents.
In one embodiment, as shown in Figure 10, the dye
composition is contacted with the dyeable material in a
manner that a thin continuous film of the dye
composition flows over the surfaces of the dyeable
material to be dyed. Thus, the entire dyeable material
is in contact with the dye composition throughout the
dyeing process. The dyeable material is accordingly
exposed to an environment which is substantially the
same as in an immersion dyeing process. Indeed, since
the film is in constant motion and flowing very rapidly,
the dyeable material is continuously exposed to fresh
dye composition. This dynamic condition cannot be
easily achieved in an immersion bath. For this
; :~
.` ` `
53
reasOn, this embodiment can be characterized as a microbath
technique. The non-reactive environment surrounds the microbath
to prevent the degradation of the dye composition.
The microbath technique is to be distinguishPd from previous
processes that spray or shower the dye composition onto the
dyeable material, or immerse the material into a dye bath. Spray
or shower techniques apply the dye composition to the dyeable
material in the form of droplets or fine discrete particles which
expose the largest liquid surface area to the ambient atmosphere.
As a result, the entire dyeable material is not in constant con-
tact with the dye composition throughout the dyeing step. More-
over, since the droplets must pas~ through the surrounding
ambient atmosphere before contacting the dyeable material, sig-
nificant heat loss occurs. This makes it very difficult to
maintain the dye composition at the appropriate temperature.
Also, at elevated temperatures-significant dye degradation occurs
because of increased mixing with the ambient air.
In an immersion technique, the entire dyeable material is
immersed in a large volume of the dye composition. Although the
material is completely covered by the dye compo~ition as in the
`microbath technique, a significantly larger quantity of dye com-
position is r~quired that also must be heated and stored. Fur-
thermore, the dye composition in the immersion process is not in
constant and rapid motion; hence, the dyeable material is not
continuously exposed to fresh dye composition.
The dyeing step is preferably conducted at atmospherlc pres-
sure. However, pressure~ above and below atmospheric pressure
can also be used.
--10--
~ Z~8753
Prior to applying the dye composition to the dyeable mate-
rial, the dye composition i5 heated to the desired elevated tem-
perature. The heating of the dye composition is conducted in a
non-reactive environment to reduce significantly the degradation
of the dye composition. The temperature selected depends ~pon
the dyePble material being dyed, the particular dye composition,
and the desired contact time between the dye composition and the
dyeable material. When the dyeable material is a synthetic mate-
rial, such as a polyester fabric, the dye composition is heated
to a temperature above the glass transition of the sy~thetic ma-
terial, but below both the melting point of the synthetic mate-
rial and the boiling point temperature of the dye composition.
One skilled in the art would select the particular dye com-
position depending upon the particular material being dyed. Usu-
ally, the dyeable material is first selected and then the partic-
ular dye composition and temperature range for the dyeing process
are chosen.
Prior to the dyeing step, the dyeable material can be pre-
heated to allow for more rapid dyeing. By preheating the dyeable
material to a temperature approximately equivalent to the temper-
~ature of the heated dye composition, a more rapid and better
quality of dyeing is achieved. Typically, when a synthetic mate-
rial such as polyester is used, it is preheated to a temperature
above the glas~ transition temperature of the synthetic material,
but below its melting point and the boiling point of the dye com-
position.
Preferably, the preheating of the dyeable material is con-
ducted in the same non-reactive environment used in th~ dyeing
~tep. In one embodiment a gaseous fluorocarbon, such a~ Freon
--11--
~:~58753
TF, i~ pa~sed over the dyeable material. However, other methods
of preheating the dyeable material can also be used.
After the dyeable material is dyed, the material is cooled
to fix the dyestuff in the dyeable material. With a synthetic
material, the cooling temperature is below the glass transition
temperature. This also prevents the dyeable material from
changing its shape, a factor that is particularly important if a
garment is being treated.
Preferably, the cooling step is conducted in a non-reactive
environment to prevent the degradation of the dye composition
still in contact with the dyeable material. As a result, when
the unabsorbed dye composition is removed from the dyeable mate-
rial in a rinsing step, it can be reused. The cooling of the
heated dyeable material can be achieved by passing fluorocarbon,
such as Freon TF in its gaseous state, over the dyeable material.
After the cooling of the dyed dyeable material, the present
process can also include the further steps of rinsing the cooled
dyeable material with a rinse liquid to remove excess dye compo-
sition and of-drying the rinsed material. The rinse step could
be accomplished by flowing a non-rea~tive compound over the
`dyeable material. Preferably, the rinse liquid is the same chem-
ical composition that is used as the non-readtive environment in
the dyeing step, but different non-reactive compounds can also be
used. This will prevent degradation o~ the dye composition and
permit its continued use in the dyeing step. However, the
dyeable material can also be rinsed and dried by other known
techniques. The rinse temperature is below ~0th the boiling
point of the rinse composition and of the dye compo~ition, as
well as the melting temperature of the dyeable material.
-12-
~2~;~'753
13
In the drying step, the non-reactive environment is
heated to vaporize any liquid and expel any gaseous
composition remaining on the dyeable material. The
amount of time needed for the rinsing and drying steps
5 depends on various ~actors, such as the type o~ dyeable
material, the dye composition solvent, and the
temperature of the non-reactive environment used in each
step.
The present process can be used in the non-aqueous
dyeing, at an elevated temperature, of a variety of
dyeable materials. The process is especially usable to
dye te~tile materials, for example synthetic materials
such as polyester. Examples o~ other synthetic
materials include polyamides, polyurethanes, acrylics,
halogenated polyolefins, polyolefins such as
polypropylene, aramids such as Kevlar and Nomex which
are trademarks of E.I. Dupont de Nemours & Co., and
epoxy plastics. The process can also dye natural
materials including cellulosic fibers, wool~ and silk.
Likewise, blends of materials such as polyester-cotton
or polyester-wool may be dyed. Other synthetic and
natural materials knoW@ in the art can also be used in
the present process.
The textile material can be in any ~orm, ~or
example, fibers, yarns, fabrics, garments or garment
components. The fabrics can be woven, nonwoven,
knitted, tufted, or needle punched. Furthermore,
entirely cut, sewn and shaped garments ready for wear,
such as pants, skirts or shirts, can be dy~d by the
process. The textile materials to be dyed can also be
fabric components that will ultimately be formed into a
completed garments.
Following are examples of the present invention,
which are intended to be merely exemplary.
- ~2S~3753
EXAMPLE NO. 1
A dye composition was prepared containing 10 g/l of
Navy Blue 2GLS manufactured by Mobay Chemical Corp (C.I.
Disperse Blue 79) in a terephthalic acid adduct of a
diester as disclosed by Wilson in U.S. Patent Mos.
4,293, 305 and 4, 394,126 and available from Crucible
Chemical Co. under the commerical name of Cruester 1000
DTR (trademark).
One half of the dye composition (Dye sath A) was
heated to 185C in air and the second half (Dye Bath B)
- was heated to 185C under a non-reactive environment of
gaseous 1,1,2-trichlorol,2,2-trifluoroethane (Freon TF
[trademark] manufactured by E.I. DuPont deNemours & Co.).
Textile material samples consisting of 100% polyester
textured filament woven fabric, partially heat set and
scoured to remove all processing additives and chemicals,
were dyed at 185C with each of the dye compositions in
their respective environments. The dye compositions were
in contact with the dyeable materials for a period of 60
seconds. After dyeing, the samples were cooled,
thoroughly rinsed with liquid Freon TF until no visible
coloration of the rinse liquid and air dried.
The two dye compositions were then aged at 185C for
a period of 4 hours. Ageing of Dye Bath A was carried out
in air, while Dye Bath B was aged in a gaseous Freon TF
environment.
After the ageing period, samples of the same dyeable
material used for the initial dyeings were dyed in the
aged dye compositions following the same dyeing procedure.
Color strength of the four dyed polyester dyeable
materials was assessed by reflectance measurements in a
ACS Color Control unit.
-14-
,
. ..
~:Z5~ i;3
Dye Composition Dye Bath Treatment % Color Strenqth
Dye Bath A Initial (Air) 100%
Dye Bath A 4 hrs. ayeing in air 15%
Dye Bath B Initial ~Freon TF) 100%
5 Dye Bath B 4 hrs. ageing in Freon TF 75%
The above data clearly shows that the loss in color
strength is significantly reduced when the dyeing
process is carried out in a non-reactive environment,
such as in gaseous 1,1,2-tri-chloro-1,2,2-
trifluoroethane (Dyebath B), as compared to air (DyebathA).
EXAMPLE NO. 2
Three dye compositions, approximately matching a
red, a peony and a slate shade, were prepared by
dissolving each dye-stuff composite tabulated below in
a terephthalic acid adduct of a diester as disclosed by
Wilson in U.5. Patent Nos. 4,293,305 and 4,394,126 and
available from Crucible Chemical Co. under the
commercial name of Cruester 1000 DTR.
Dyestuff in arams/liter Ref.Note ~ed Peony Slate
Resolin Red F3BS (1) 14.21
Eastman Yellow 6GLSW (2) t3) 1.69 - 1.58
Resolin Blue FBL (1) (3) _0.08
Resolin Yellow 5GL (1) - 0.10
Polyester Red YSL (2) (3) -15.74
Polyester Navy Blue RDH (2) - 14.02
Ref.Note:
(l) The Resolin dyestuff is manufactured by the
Mobay Chemical Corp.
(2) The dyestuff is the press cake equivalent
manufactured by Eastman Chemical Products,
Inc.
(3) Eastman Yellow 6GLSW: C.I. Disperse Yellow 88
Resolin Blue FBL : C.I. Disperse Blue 56
PoLyester Red YSL : C.I. Disperse Red 339
Two sets of dye compositions were prepared by m.ixing the
dyestuff composite for each shade into the Cruester 1000 DT~.
The first set was then heated to 185C in air with stirring. The
second set was heated to 185C with stirring under a non-reactive
environment of gaseous 1,1,2-trichloro-1,2,2-trifluoroethane
(Feon TF manufactured by E.I. DuPont de Nemours & Co.).
Samples of 100% polyester textured filament woven fabric,
partially heat set and scoured to removed all processing addi-
tives and chemicals, were dyed at 185C in ambient air for the
set of dye compositions prepared by heating in air and under
Freon TF for the set prepared by heating in a non-reactive envi-
ronment. The dye compositions were in contact with the dyeable
material samples for a period of 60 seconds. After dyeing, the
samples were.cooled in their respective environments, thoroughly
rinsed with liquid Freon TF until no visual coloration of the
rinse liquid, and then air dried.
The color strength of the dyed polyester dyeable materials
~was a~sessed by reflectance measurements in a ACS Color Control
Unit. The percentile comparative color strengths are shown
below:
Dy~ing Process Environment
Shade Freon TF Air
-
Red 100% 78%
Peony lO0~ 77%
Slate 100% 52
16-
~;~587~3
The tabuLated data indicates that heating the dye composi- ;
tion in air was ~ufficient to reduce significantly the coloring
strength of the dye compositions as compared to the ~ame prepara-
tion and dyeing under a non-reactive environment.
S EXAMPLE NO. 3
A dye composition was prepared by mixin~ 10g of Polyester
Navy Blue RDH, manufactured by the Eastman Chemical Products,
Inc., in 1000 ml of a terephthalic acid adduct of a diester as
disclosed by Wilson in U.S. Patent Nos. 4,293,305 and 4,394,126
and available from Crucible Chemical Co. under the commercial
name of Cruester 1000 DTR. One hal~ of the dye composition (Dye
Bath C) was heated to 185C in air and the other half (Dye Bath
D) was heated to 185C under a non-reactive environment o~ gase-
ous 1,1,2-trichloro-1,2,2-trifluoroethane (Freon TF manufactured
by E.I. DuPont de ~emours & Co.).
Samples of l00~ polyester textured filament woven fabric,
partially heat set and scoured to remove all processing additives
and chemicals, were dyed at 185C with each dye composition in
their respective environments. The dye compositions were in con-
tact with the dyeable materials for a period of 30 seconds.
~After dyeing, the samples were cooled, thoroughly rinsed with
liquid Freon TF until no visibLe coloration of the rinse liquid,
and dried in air. Dye Bath C and Dye ~ath D were then aged for 4
hour~ at 185C in, respectively, air and gaseous Freon TF envi
ronments.
Samples of the same dyeable material used for the initial
dyeings were also dyed with the aged dye compo~itions following
similar dyeing procedures.
:
;87~3
i The color strength o the dyed polyester sample~ was asses-
'sed by reflectance measurements in a ACS Color Control Unit. The
reflectance of the sample dyed in the initial Dye Bath D under
Freon TF was set at 100% and comparative percentiles for the
other reflectance measurements were computed and are tabulated
below:
Dye Composition Dye Bath Treatment~ Color Strength
Dye Bath C Initial (Air) 12.5
Dye Bath C 4 hrs. ageing in air 3.5
Dye ~ath D Initial (Freon TF)100
Dye Bath D 4 hrs. ageing in Freon ~F 26.5
Polyester Navy Blue RDH is an extremely sensitive dyestuff
and the above data show the very significant loss of initial
color strength and the total degradation after 4 hours ageing in
air. Moreover, the actual blue color of the dyestuff was com-
pletely lost and the dyed dyeable material sample had a dirty
straw shade.
EXAMPLE ~O. 4
The preparation, dyeing, and ageing procedures in Example 3
were repeated utilizing, this time, a dye composition containing
10 g/l of Orange BRT manufactured by the Eastman Chemical Prod-
ucts, Inc., (C.I. Disperse Orange 145) in a terephthalic acid
adduct of a diester as disclosed by Wilson in U.S. Pa~ents
4,293,305 and 4,394,126 and available from Crucible Chemical Co.
under the commercial name of Cruester 1000 DTR.
The color ~trength of the four dyed polyester samples was
assessed by re~lectanc~ measurements in a ACS Color Control Unit.
The reflectance of the sample dyed in the initial dye composition
prepared under Freon TF (Dye Bath D) was set at 100% and
-18-
~;25i~37~i3
comparative percentiles for the other reflectance measurements
were computed and are tabulated below:
Dye Composition D~e Bath Treatment~ CoIor Strengt'n
Dye Bath C Initial (Air) 100
S Dye Bath C 4 hrs. ageing in air 49
Dye Bath D Initial (Freon TF)100
Dye Bath D 4 hrs. ageing in Freon TF 100
The orange is a considerably more stable dyestuff than the
Navy Blue used in Example No. 3. However, over one half of the
color strength is lost after ageing the dye composition for 4
hours in alr. Under a non-reactive environment, no degradation
of the color strength was noted.
EXAMPLE NO. 5
A dye composition was prepared containing 1 g/l of C.I. Dis-
lS perse Blue 6 in a diester as disclosed by Wilson in U.S. Patent
Nos. 4,293,305 and 4,394,126 and available from Crucible Chemical
Co. under the commercial name of Cruester 1000 D.
A 1 ml aliquot of the dye composition was withdrawn and di-
luted to 100 mls with 1,1,2-trichloro-1,2,2-trifluoroethane
(Freon TF manufactured by E.I. DuPont de Nemours & Co.). The di-
~luted sample was analyzed in a Bausch & Lomb Spectronic 21. The
transmi~sion value was measured at 620 nanometers (nm) and was
set as the base value (100%). All the other transmission mea-
surements in this example were compared to this original base
strength of l g/l.
The dye composition was then divided into three parts and
aged at 185C for 12 hours under the following conditions:
Dye Bath E : Ageing wa~ carried out in air.
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Dye Bath F : A stream of air was bubbled through the dye
composition during the entire ageing period.
Dye Bath G : The dye composition was aged in a Freon TF
environment.
At specific time intervals, 1 ml aliquots were removed rom the
Dye Baths (E, F, and G), diluted to 100 mls with Freon TF, and
the transmission was measured at 620 nm. with a Bau~ch & Lomb
Spectronic 21. The transmission values were then compared to the
original, and a percentile was computed. The following results
were obtained.
~ Color Strength
Dye Bath E Dye Bath FDye Bath G
Ageing (Hours) AIR AIR 8UBBLING FREON TF
Original 100 100 100
0.5 96.0 93.0 100
1.0 - 83 100
1.5 90.5 75.5 100
2.0 - 69.5 100
2.5 - 66.5 100
4.5 62.0 100
~6.0 - 60.0 100
.0 - 58.0 100
9.0 65.0 55.0 100
12.0 59.0 51.0 100
The above data show the effect of air on the high temperature
ageing characteristics of the dye composition. More specifical-
ly, the rapid degradation of Dye Bath F, when air is bubbled
through the liquid, is indicative of the results that could be
obtained in a proces3 in which the dye composition is sprayed or
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showered over the dyeable material. The effect of maintaining
the dye composition in a non-reactive environment is apparent,
No change occurred even after ageing for 12 hours at 185C.
Reference is now made in detail to the present preferred em-
bodiment, as illustrated in Figures 1-17. In accordance with the
invention, an apparatus 10, for the dyeing of shaped dyeable
materials comprises means for surrounding a shaped dyeable
material with a non-reactive environment in a treatment chamber
14 and means for flowing a thin continuous film of the dye compo-
sition over the surfaces of a dyeable material at an elevated
temperature in a non-reactive environment. The apparatus lO i3
especially useful in dyeing dyeable materials in the form of a
shaped article, such as a garment.
The apparatus 10 also can comprise: means for transporting
the shaped dyeable material within the apparatus in a treatment
chamber 14 means for preheating the shaped dyeable material
prior to flowing the thin continuous fiLm over the dyeable
material and means for cooling the dyed shaped dyeable material.
The apparatus can further include rinse means for rinsing the
dyed shaped dyeable material and drying means for drying the dyed
~shaped dyeable material.
A4 shown in Figures 1 to 3, the apparatus includes a sta-
tionary cylindrical vessel 9 with a vertical axis around which is
rotated a carousel unit 13, having a plurality of treatment
chambers 14 for supporting and transporting simultaneously
several shaped dyeable materials 12 from work station lS to work
station 15.
More particularly, the carousel unit 13 has a plurality of
treatment chambers 14, each of which contains a shaped dyeable
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material 12 that i3 to be treated in the apparatu~ 10. The
shaped dyeable material 12, contained in each treatment chamber
14, is moved from one work station to another as the carousel
unit 13 rotates. A different treatment, such as loading, pre-
heating, dyeing, cooling, rinsing, drying, and unloading is per-
formed on the shaped dyeable material 12 at each station 15.
As shown in Figure 1, the work stations 15 include a loading
and unloading station 15A, a preheating station 15B, a dyeing
station 15C, a cooling station 15D, a rin~ing station lSE, and a
drying station l5F. In the loading and unloading station 15A,
the shaped dyeable material 12 mounted on a carrier 70 (Fig. 4)
is either loaded or unloaded from the treatment chamber 14, de-
pending upon whether the treatment process is beginning or
ending.
The chamber 14 has a port 16, through which the shaped
dyeable material 12 is loaded and unloaded. Pre~erably, the port
16 is in the top cover plate 11 of the apparatus 10, but it may
be located elsewhere in the apparatus depending upon the compound
used for the non-reactive environment. With some compounds, the
port 16 may be sealed to render the apparatus 10 airtight.
`Preferably, if the compound u~ed as the non-reactive environment
i8 heavier than air, the port 16 can be open and located in the
top cover plate ll, since the non-reactive compound displaces the
ambient air from the apparatus 10.
Once the first shaped dyeable material 12 to be proceqs is
positioned on the carrier 70 and then loaded into one of the
chambers 14, the carousel unit 13 i~ rotated so that ~he newly
loaded chamber 14 is in the preheating ~tation 15B. (Figs. 5 and
6) In the preheating station 15B, the shaped dyeable material i
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heated to a temperature approximately equal to that of ths dye
~composition to be applied in the dyeing station 15C. As the ca-
; rousel unit 13 rotates, the next empty chambers 14 is then posi-
tioned in the loading and unloading station 15A so that another
S shaped dyeable material can be loaded into the empty chamber 14.
After a predetermined time period, the carousel unit 13 is
rotated and the preheated shaped dyeable material 12 is posi-
tioned in the dyeing station lSC. In the dyeing station 15C, the
dye composition is applied to the shaped dyeable material 12.
The predetermined time period depends upon the time necessary to
effectuate the desired dyeing of the shaped dyeable material 12
in the dyeing station 15C. During the time needed to dye the
shaped dyeable material 12, unloading and loading of the chamber
14, under the loading and unloading station 15A, takes place.
lS The predetermined time period for rotating the carousel unit 13
is governed by the dyeing time; therefore, the shaped dyeable
material 12 in each chamber 14 remains at each worX stations 15
the same amount of time as determined by the dyeing cycle.
After the shaped dyeable material 12 in the dyeing work
station 15C i~ dyed to the desired coloration and the carousel
unit 13 is again rotated so that the dyed shaped dyeable material
is positioned in the cooling station 15D. The shaped dyeable
material 12 is then cooled to a temperature su~ficient to fix the
dyestuff in the ~haped dyeable material and to prevent the shaped
dyeable material from changing its shape.
After sufficient cooling, the carousel unit 13 is then ro-
tated to place the cooled shaped dyeable material 12 in rinsing
stations 15E. (Fig. 12) The used, bu~ non-ab~orbed, excess dye
compo~ition is rinsed from the ~haped dyeable material and
recycled for u~e in ~he dyeing station lSC.
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53
Once the shaped dyeable material 12 is rin~ed, the carousel
13 is rotated ~o that the dyed shaped dyeable material is posi-
tioned in the drying station lSF. The shaped dyeable material is
heated to vaporize any excess liquid. After drying, the shaped
dyeable material 12 on the carrier 70 i~ unloaded from the
chamber 14 through port 16 in the unloading station 15A.
As ~hown in Figure 3, the plurality of treatmen~ chambers 14
that form the carousel unit 13 are ~eparated from each other by
walls 21. The walls ~1 can be constructed to seal each chamber
14 from the adjacent chamber to prevent the non-reactive environ-
ment in one chamber 14 from leaking into the other chamber 14.
Preferably, the same non-reactive compound and environment i5
used in all of the chambers 14 50 that quch a tight seal between
the chambers 14 need not be maintained by the walls 21.
The carousel unit 13 allows all of the stations 15 to treat
simultaneously a number of shaped dyeable ~aterial 12 that are
positioned on a plurality of carriers 70 within a plurality of
chambers 14. Consequently, ~haped dyeable material is being
dyed, while others are simultaneously being unloaded, loaded,
preheated, cooled, rinsed, and dried. Usually, the number of
~cham~r~ 14 forming the carousel unit 13 corresponds to the
number of work stations lS so that a chamber 14 is positioned in
each work station 15 every time the carousel unit 13 rotates.
A~ embodied herein, the means for transporting the shaped
dyeable material 12 within the apparatus 10 in the chamber 14
between the various stations lS includes the carousel unit 13
with ~he garment carriers 70 and a mean~ for rotating the ca-
rou~el unit 13. A~ embodied ~erein, the rotating means includes
a motor and gear reducer 18 for rotating the carousel unit 13. A
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carou~el p~sition ~witch 20 determines the movement of the
carousel unit 13. However, other known means for rotating the
carousel unit 13 among the stations 15 can also be used.
As the chamber 14 rotates among the various work stations, a
non-reactive environment is maintained around the shaped dyeable
material 12 in the chamber 14. This prevents the degradation of
the dyestuff and as a result the dye composition can be recycled
and reused repeatedly for multiple dyeing~. Preferably, the same
non-reactive environment is present in the chamber 14 at all of
the stations 15A to lSF to preserve the integrity of the non-
reactive environment within the stationary cylindrical ve~sel 9.
As embodied herein, the means for surrounding the shaped
dyeable material 12 with a non-reactive environment in the treat-
ment chamber 14 includes a ga~ vapor generator 24 for producing
the non-reactive environment. Preferably, as shown in Figure 4,
the vapor generator 24 is stationary and located in the loading
station lSA below the chamber 14.
The vapor generator 24 vaporizes the compound that is to be
used as the non-reactive environment. The compound is fed into
the vapor generator 24 from a tank 19 through a feed line 22. A
~valve 23 controls the flow of the feed. A steam source 17 with a
condensate trap 25 is used as a heating source for the vapor gen-
erator 24.
As the generator 24 fills the chamber 14 with the compound
of the non-reactive environment, some of the non-reactive com-
pound escapes through ~he port 16 and is collected by a condenser
27 positioned on the top cover plate 11 of the appara~ 10. The
condenser 27 condenses the collected compound to a liquid and
returns it throuyh conduit 26 to either the tank 19 or the vapor
generator 24. A valve 34 controls the ~low in the conduit 26.
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. I
The condensed compound can also be supplied to the rinse
~tation l5E for use as a rinse liquid through conduit 28 con-
trollea by valve 35, if the rinse station 15E use~ the szme non-
reactive compound for rlnsing a~ in the vapor generator 24. Sim-
ilarly, reclaimed rinse liquid can be recycled to the tank 19
from a distiLlation unit 118 that receives its feed from the
rinsing station 15E, as more fully described below.
Preferably, the chambers 14 are maintained at a temperature
above the condensation temperature of the compound forming the
non-reactive environment. Once the non-reactive environment is
established in all of the chambers 14, the carousel unit 13 is
rotated continuous~y among the various wor~ stations 15, without
the need of reestablishing a non-reactive environment in the
chambers 14 each time.
In the preheating work station lSB shown in Figures 5 and 6,
the means for preheating the shaped dyeable material 12, prior to
flowing the thin continuous film of the dye composition over the
shaped dyeable material 12, includes gas blower means for
circulating a gas forming the non-reactive environment around the
shaped dyeable material 12 and a heating unit 32 for heating the
~circulating gas. As embodied herein, the gas blower means
includes a gas blower 30 and a conduit 31 leading the gas from
the gas blower 30 into the chamber 14. The gas exits from the
chamber 14 through a return outlet 33 to the blower 30 and the
heating unit 32.
The heating unit 32 preferably contains one or more heating
coils, as well a various temperature controls and dampers. The
heating coils can have a steam source to heat the coils. Prefer-
ably, the ga~ blown on the shaped dyeable material is the
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,,
compound, as defined above, that provide~ the non-reac~,ive
environment.
A~ shown in Fig. ll, in the preheating station 15B, the con-
duit 31 is positioned above the shaped dyeable material 12 in the
chamber 14 to allow the heated gas to flow onto the shaped
dyeable material 12 on the carrier 70. Thi~ positioning provides
an effective and efficient heating of the garment 12.
After the dyed material is preheated, the chamber 14 is ro-
tated to the dyeing work station 15C shown in Figures 7-9. The
L0 means for flowing a thin continuous film over the shaped dyeable
material includes an applicator head 46 for flowing a continuous
thin film of the dye composition over the surfaces of the shaped
dyeable material 12, and means for supplying ths dye composition
to the applicator head 46, such as a pump 57 for pumping the dye
composition from a main tank 44 through a conduit 48 to a heating
unit S0. The heating unit 50 heats the dye composition prior to
supplying the dye composition to the applicator head 46.
When a shaped dyeable material 12 is not in the chamber 14,
a diverter valve 41 prevents the flow of the dye composition to
the applicator head 46. Rather, the dye composition is returned
to th~ main tank 44 through a bypass line 43. This allows the
dye composition to be maintained at the dyeing temperature by
continued circulation and heating while the carousel unit 13 ro-
tates.
The main tank 44 ic located in the dyeing station 15C below
the carousel unit 13~ The main tank 44 can be ~elatively small,
such as 5 gallon~, in comparison to previous apparatus, due to
the efficiency of the present dyeing process. The main tank 44
is maintained in a non-reactive environment to prevent dye
degradation.
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A reservoir tank 51 contains a re~erve ~upply o~ dye compo-
sition for use as the 9upply of the dye composition in the main
tank 44 diminishe~. The dye composition rom the rçservoir tank
51 is fed into the main tank 44 through a conduit 52 controlled
by valve 53. A conduit 47 can also feed heated dye composition
through the heating unit 50 to the reservoir tank 51 in which the
~ye composition is stored until it is needed. A valve 49 diverts
the flow between the conduit 48 and the conduit 47.
As shown in Figures 7 and lO, the applicator head 46 i~
preferably positioned directly above the shaped dyeable material
12. The applicator head 46 applie~ the dye compo~ition in a
manner that a thin continuous film 59 of the dye composition
flows over the all the surfaces of the shaped dyeable material
12, as shown in Figure lO.
To provide the continuous thin film 59 of the microbath, the
applicator head 46, as shown in Figures 13 and 14, includes an
upper horizontally extending circuit retaining wall 58 having a
circumferential ring 60 depending from the outer periphery 63 of
the upper wall 58, and a lower horizontaL wall 62 connected to
the upper wall 58. The periphery 65 of the lower wall 62 is
spaced inwardly from the circumferential ring 60 to define an an-
nular downwardly facing discharge opening 68 for the discharge of
the dye composition. A dispersion plenum 66 ~s formed between
the upper wall 58 and the lower waLl 62 for dlspersing the dye
composition from a coupling 56, through the plenum 66, and to the
discharge opening 68.
To achieve the proper flow, the diameter of the lower wall
62 correspond to the diame er of an inner frame 74 of the carri-
er 70 (Fig. lO).
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A3 ~hown in Figures 7 and 10, the applicator head 46 is po-
sitioned directly above the carrier 70, when the chamber 14 i~ in
the dyeing work station 15C. Such a positioning permits the dye
compositlon to flow out of the applicator head 46, through the
S discharge opening 68, and into a circumferential inlet 72 of the
carrier 70. The speed of the dye flow d~pends upon the dye com-
position, the material being dyed, the shape of ~he carrier 70 on
which the mat~rial is positioned, and the compound used as the
non-reactive environment.
~s shown in Figures 10, 15 and 16, the carrier 70,
preferably, has an inner frame 74 with an outwardly extending
bottom wall 73 and an outer frame and qupport 76 connected to the
bottom wall 73 to form a trough con~iguration. The inner frame
74 and the outer frame 76 together define a circumferential inlet
72 that lies horizontally above the bottom wall 73. The shaped
dyeable material 12, such as a par~ of pants, a skirt, or a
shirt, is fitted onto the outer frame and support 76 of the car-
rier ~0.
Preferably, the outer frame 76 is made of a porous material
such a~ woven wire screen that allows the dye composition to flow
~over and ~hrough to contact all sides of the dyeable material 12.
The outer rame 76 is constructed to impart a smooth, dimensional
shape to ~he desired areas of the dyeabLe material 12. In the
particular case where the dyeable material 12 is a pair of pants,
the carrier 70 includes flat blades lS0 extending downwardly from
the outer frame 76 ~Fig. 16). The blade~ 150 are designed to
impart creases to the leg portions of the pair of pants, and to
maintain the surface of the dyeable material 12 in a smooth and
unwrinkled condition during processing. The flat blades 150 may,
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.,
"if desired, be perforated to allow the dye cornposition to flow
over and through or could be two narrow bands with appropriate
spacing and supports coinciding with the edges of the blades 150.
During the dyeing process, the dye composition flows from
the applicator head 46 into the circumferential inlet 72 of the
carrier 70. Some of the dye composition then flows over the top
rim 77 of the outer frame 76 onto the outside portion of shaped
dyeable material 12. Some of the dye composition al~o flows out
through holes 79 (Fig. 10) in the sieve liXe material of the
outer frame 76 to contact the underside of the shaped dyeable
material 12 held on the outer frame 76. In thi~ manner, both
sides of the shaped dyeable material 12 on the outer frame 76 are
contacted by the continuous thin film 59 of the dye composition,
in accordance with the microbath technique.
The carrier 70 is held in proper position within the chamber
14, as the carousel unit 13 rotates, by attaching a top lip 75 of
the carrier 70 within a ring 69 formed by a flange 71 on each
wall 21 of each chamber 14, as shown in Figures 10 and 11. Each
carrier 70 has bars 78, as shown in Figures 10 and 11, that coact
with the ring 69 to hold the shaped dyeable material 12 on each
carrier 70 in proper position for treatment by the work stations
15 .
The outer frame 76 can also include a clip 82, along the rim
77 of the outer frame 76, to hold the shaped dyeable material 12
in place on the ou~er frame 76. The outer frame 76 can be con-
structed in a number of separate pieces to form the shaped
dyeable material 12, placed on the carrier 70, into ~he desired
shape. The i~e and shape of the outer frame 76 generally
corre~ponds to the size and shape of the shaped dyeable material
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12 that is to be positioned on the outer frame 76. For e~ample,
if the shaped dyeable material 12 is a pair of pant~, the outer
frame 76 can be constructed to provide to the pants the final de-
sired shape.
After the dye composition ha~ been applied to the shaped
dyeable material 12, the dyed shaped dyeable material in the
chamber 14 is rotated to the cooling work station 15D. As em-
bodied herein, the cooling means includes gas blower mean for
circulating a gas around the shaped dyeable material 12 and a
cooling unit 104 for cooling the gas circulating arouAd the dyed
shaped dyeable material. As embodied herein and shown in Figure
2, the gas blower means includes a gas blower 102 and a blower
conduit 103 leading ~he cool gas from the gas blower 102 into the
chamber 14. The gas exits from the chamber 14 through cooling
exhaust outlet 105.
The cooling unit 104 preferably contains one or more cooling
coils as well as various temperature controls and dampers. The
cooling coils can have a water source to cool the coils. Prefer-
ably, the cool gas blown on the dyed shaped dyeable material is
one of the above identified compounds that provides a non~reac-
tive en~ironment. The cooling station lSD i~ constructed similar
to the preheating station 15B shown in Figures 5, 6, and 11.
After the shaped dyeable material is cooled, the chamber 14
is rotated to the rinsing work station 15E shown in Figure 12.
Pre~erably, as shown in Figure 12, two rinsing ~tations 15E-l and
15E-2 having individual applicator heads 108 and 112, are used to
apply a rinse liquid to the dyed shaped dyeable material. Fresh
rinse liquid from a main tank 113 rin~es shaped dyeable materials
in rinse stations 15E-2 that have already been rin~ed by the
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ifir~t rinse ~tation 15E-1. The initial rinse of the freshly dyed
iand coole~, but unrinsed, shaped dyeable material 12 i3 carried
out in rinse station l5E-l that receives its rinse liquid ~rom
the downstream rinse station 15E-2. A pump 106 pumps the rinse
liquid from a collection tank 114 through conduit 107 to the
applicator head 108.
Consequently, recycled rinse liquid is used to rinse ini-
tially the shaped dyeable material 12 in rinse station 15E-l
while fresh rinse liquid is applied to the the once rinsed shaped
lQ dyeable material 12 in rinsa station 15E-2. This countercurrent
rinse process permits the use of the cleaner or fresher rin~e
solvent on the shaped dyeable material 12 to remove completely
the excess dye composition after it has already been rinsed once.
The rinse solvent used in the first rinse station 15E-l, conse-
quently, is very dirty and it is collected in a tank 115, prior
to being pumped by pump 110 through a conduit 111 to the distil-
lation unit 118. Various valves 109 control the rinse liquid
flow between the various components of the rinse stations.
Only one rin~ing station, however, is necessary for the
operation of the apparatus 10. As embodied herein, the rinsing
mean~ includes the applicator head 112 flowing a continuous thin
film of a rinse liquid over the qurfaces of the dyed shaped
dyeable material 12~ a means for supplying the rinse liquid, such
as a pump 122 to the applicator 112; and means for recycling the
rinse liquid applied over ~he dyed shaped dyeable material 12.
The rinse liquid is preferably one of the above identified com-
pound~ that provides a non-reactive environment.
As embodied herein, the recycling means includes a distilla-
tion unit 118 (Fig. 12) to s~parate the rinse liquid from the dye
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. .
~composition solvent; the collection tank 114 positioned beneath
the ch2mber 14, and one or more conduits 116 for transporting the
rinse liquid between the main tank 113 and the applicator head
112.
The applicator head 112, used to apply a continuous flow of
the rinse liquid over the dyed shaped dyeable material 12 in the
rinsing work stations 15E, i~ similar to the applicator head 46,
used to apply the dye composition to the undyed shaped dyeable
material 12 in the dyeing work station 15C. The applicator head
112 is similarly positioned over the shaped dyeable material 12
on the carrier 70 so that a thin continuou~ film of the rin~e
liquid flows over all the surfaces of the shaped dyeable material
12 to form a microbath of the rinse liquid.
After the shaped dyeable material is rinsed, it is rotated
to drying wor~ station lSF as shown in Figures 1 and 2. As em-
bodied herein, the drying means includes a gas blower means for
circulating a gas around the dyed shaped dyeable material 12 and
a heating unit 90 for heating the gas circulating around the dyed
~haped dyeable material. As embodied herein, the gas blower
mean~ includes a gas blower 92, similar to the blower 30 of
Figur~ 5 and 6 that is used to preheat the shaped dyeable
material, and a blower conduit 94 leading the hot gas from the
gas blower 92 into the chamber 14. The hot gas exits from the
chamber 14 through the outlet 95.
The drying ga~, preferably, i~ one of the above-described
compounds that provide a non-reactive environment. Two ~eparate
drying station~ 15F can be used in uccession to dry effectively
the shaped dyeable material. The drying station 15F is
constructed similar to the preheating station 15B Rhown in
Figure~ 5, 6,~ and 11.
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34
The heating unit 90 preferably contains one or more
heating coils, as well as various temperature controls
and dampers. The heating coils can have a steam source
to heat the coils.
After the shaped dyeable material 12 i5 dried, the
chamber 14 is rotated to the unloading station 15A.
The dyed and dried shaped dyeable material is removed
from the chamber 14 through port 16.
Other embodiments of the invention will be apparent
to one skilled in the art from a consideration of the
specification or the practice of the invention disclosed
herein. It is intended that the specification and
examples be considered as exemplary only with the true
scope and spirit of the invention being indicated by
the claims.
