CA1051612A

CA1051612A - Continuous dyeing of cellulose fibers with reactive dyestuffs

Info

Publication number: CA1051612A
Application number: CA219,558A
Authority: CA
Inventors: Hans-Ulrich Von Der Eltz
Original assignee: Hoechst AG
Current assignee: Hoechst AG
Priority date: 1974-02-09
Filing date: 1975-02-07
Publication date: 1979-04-03
Also published as: NL175447B; NL175447C; GB1494446A; BE825355A; JPS5542192B2; FR2260658A1; FR2260658B1; IT1031561B; DE2406257B2; DE2406257A1; CH137275A4; IN142881B; NL7501302A; CH595504B; ZA75398B; JPS50112575A

Abstract

Abstract of the disclosure Process for the continues dyeing of flat textile structu-res made of cellulose fibers and their mixtures with synthetic fiber materials by applying onto the web of fibrous material an aqueous solution of at least one reactive dyestuff together with a fixation agent mixture of a liquid alkali metal silicate (water glass) and an mixture of a liquid alkali metal silicate placing the material thus treated into a material tank, ex-posing the material in said tank in a outtled-up or opened-out condition to humid heat, so that the dyestuff is fixed by the dwelling operation, and finally removing the material again continuously from the material tank.

Description

~1516i~
The present invention relates to a process for the continuous dyeing of cellulose fibers with reactive dyestuffs.
The advantages of the pad short-dwell process for the dyeing of cellulose fibers with reactive dyestuffs have been acknowledged all over the world. However, the discontinuous and/or semi-continuous operation of this dyeing process has always been thought of as a drawback: as has been well-known, this most important process up to the present time for the fixation of reactive dyestuffs is performed by way of padding the dyestuff solutions con-taining an alkaline agent onto the material and by allowing the material thus treated to dwell at room temperature for at least 90 minutes, normally for 2 to 4 hours, or even over night.
According to the present invention there is provided a continuous process for dyeing of flat textile material composed of cellulose fibers or of a mixture of cellulose and synthetic fibers by means of a reactive dyestuff, which process comprises padding, at a temperature of from 20 to 80C, the tex-tile material with a padding liquor which is an aqueous solution of at least one reactive dyestuff, about 25 to about 350 grams per liter of padding liquor of a liquid alkali metal silicate of from 37 to 60 Bé and about 5 to 150 grams per liter of padding liquor of an aqueous alkali metal hydroxide of from 30 to 45Bé~ the composition of the padding liquor being subject to the re-quirement that the weight ratio of alkali metal silicate to alkali metal hy-droxide is in the range of from 1:0.1 to 1:0.5, placing the padded textile material in a dwelling chamber, exposing the textile material in cuttled-up or opened-out condition in the chamber to humid heat in the above-mentioned temperature range fo.r from 5 to 30 minutes, the temperature in the dwelling chamber being controlled by means of infra-red radiators and steam injection, so that the dyestuff is fixed by the dwelling operation, and continuously re-moving the textile material from the dwelling chamber.

~ - 2 -61~
Preferred solutions of liquid alkali metal silicate (water glass) are of about 49Be and preferred solutions of aqueous alkali metal hydroxide are of about 38Bé. Preferably the textile material spends from 10 to 20 minutes in the dwelling chamber at a temperature of from 30 to 50C.

B - 2a -HOE 74~ 0~

According to the above-mentioned procecses~ dyeing results are obtained which show a full oolor yield even at a dwellin~
*ime that has been considerably reduced. This result is only poscible if a mixture of alkali metal silicate(water glas6)and alkali metal hydroxide (optionally with the addition of soda) is used a3 fixation agent for tha reactive dyestuffs applied, inste~d o~ the alkali metal hydroxide used so ~ar. The con-centrations of the alkaline substances required in order to obtain a satisfactory fixation rate still permit a reliable operation due to the high water glass content~
~ he application o~ the dye bath is effected by mean~ of a Xnown padding unit, by way o~ a spraying or ~oaming proces~.
In order to increase the fixation rate, the textila material is padded, according to the invention, at a temperature in the range of from 20 to 80 C, pre~erably from 30 to 60 C. This can be achieved by introducing the dye liquors int~ tha padder in a pre-heated condition, or by applying them to the goods in a trough that may be heated, or by making the fibrous mat0rial pass the dye application device already in a pre-heated state.

The impregnation itself may also be effected ~ithin the pre~
heated dwelling ~hamberr After the dyestuf~ has been applied, the web of te~tile material is preferably placed on a sieve belt, while being cuttled~up in a slanting posltion (material tank), ànd is

2~ allowed to dwell. This endless sieve belt may be arran~ed horizontally or may be inclined. It is also possible to use a single lon~ belt or several belts whiGh have been arranged on~

above the other. This belt or these subdivided belts have been zg placed into a closed unit, the total capacity of which ls in , i .

- . , : .: ,. .. ... . .
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- : .
.:, .

~IOE 74/F 03~

the range of from 200 to 1Q00 m, prefe~ably from about 400 to 800 m of textile web. In this unlt an operation resulting in material rates of from 10 to 80 meters per minute i5 posslble.
The temperature in the material tank9 in which the material is heated to a temperature of up to 80C - as has been mentioned alreadr - i9 controlled by means of i~ra-red radiators, since this process does not require too much energy, and also by steam in~ection at the same time. This method en6ures a co~stant moisture on the material which is mai~tained at an e~act level.
A ~uction treatment of the material by mean~ of humid hot air can also be effected. The ~ieve belt unit is ver~ suitable for all suction and injection processes, as the material is present o~ $he sie~e belt either in an ~pset or plaited down form, or i~ lying completely flat. It is also possible to make steam pass S throu~h the material on the sieve belt where it i9 lying in opened-out condition.
At a temperature in the material tank of ~rom generally 20 to 80 C, there is no risk that spots may be formed through the development of condensation water, since a very exact temperature and humidity co~rol within this range i9 possible.
The development of this process has helped to reaoh a technical goal that ha5 been ai~ed at for a lo~ ti~e. It was surprising and could not ha~e been foreseen that the difficulti0s in the fixation of reactive dyestuffs in the dwelling process can be overcome by means of the mixture of the alkaline sub-stances. In ~pite of the C02 content of the air in the dwelling ehamber, the alkali metal ~ilicate (water glass) in this process pre~ents the alkalinity from being const~ntly reduced during the 29 fixation process, which would then result in an insufficient -. ; ". .
- :. ~ ; ' ' . . ~ .
,, .

HOE 74/~ 038 fixatio~ of the dyestuffs. Besides, temperat~re deviations towards a higher range cannot adverse1y affect the dyeing re-sult. Al~o, the moisture content within the unit prevents the dyeing from drying out. The slightly alevated temperature in combination with the mixture of t;he alkaline sub~tances - resultQ
in a suitable fixation time, Moreover, this required tempera-ture range is very easy to control. There is no need to use an extremely large amount of alkali metal hydroxide.
~ With regard to the fea~ibility of the olaimed process in practice, it was also not to be expected that there is no un-evenness of the dyeings which would normally appear through the piling up of the moist matarial.
As comparad against the wetsteaming proce~s known hitherto, the new process results in a considerably lower tend~ncy towards hydrolysis of the reactive dyestuffs, d~e to the mixture o~
the alkaline substances used according to the inv~ntion. This leads to an increased color yield, in particular with deep shades.
For the process of the in~ention, use may also be made of dyestuff combinations which have a lower ~ixation rate. In these cases, the dyestuff fixation can be completed by a ~teaming -process, for example at 103C, following the dwelling process, or by dipping the material coming from the dwelling process into a hot solution of the alkali metal sllicate (water glass).
Here again, it is the ~ixture of alkall metal hydroxida solution and water glass which prevents any expected dif`ficulty from appearing. There is no need to e~actly maintain the temperature of these after~tr~atment processes; also, the steamer is not required to be absolut~ly free from air9 and a possible exceedin~
29 of the steaming time does not lnvolve any drawbacks. A final '.

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: :
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., ~10 ~,3~8 passage of th~ fibrous material through a hot solution of alkali metal sil:icate and alkali metal hydroxide ~olution may also force an immediate fixation. The advantage of t}le process according to the invention is to be seen in the fact that the color yield i8 markedly higher for the described combination of dwelling phase and hot after-fixation than for the operation omittin~
the de~cribed dwelling process, ~rhich may be explained by both the rinsing effect and th0 higher hydrolysis r~action.
The new process can be used for woven goods made of cellulo3e fibers and their mixtures with synthetic fibers, as well as ~or knitted fabrics and particularly for tubular knitted goods, terry cloth goods and all velour and velvet materials.
The so-called dwelling-~ixation process can also be used ~uccessfully for the dyeing of mixed fabrics made ~rom poly~
e~ter/cellulose fibers~ In this case, the pol-yester fiber portion is at first dyed with disperse dyest~ffs according to the Thermosol process, and subsequently the cellulose fiber component i9 dyed in accordance with the proce~s of the in~
vention. However, it is also possible to dye the cellulose fiber first, if reaotive dyestu~fs ~re used that are resistant to hydrolysis. During the time in the material tank, during the washing process and also during the subsequent thermo-f~ation there may be a promotion of the bulkines~ of the goods each time, for suitable fiber material. It is also possible to dye the polyester fiber subsequently in a jet dyeing devlce.
~ As reactive dyestuffs there may be mentioned, for the present proces~, the organic dyestuf~s k~own by this term.
These are predominantly those dyestuffs ~hich contain at least 2~ one group reactive with polyhydrox~l fibers, a precursor to ' ' - . ' ', ' ' ' . ' ' ' ' ' 7:C ` .`' , '' ,' ' ~ ~ '', ' , ': , , ' .
.

~ F 0~8 this group, or a substituent reactive with the polyhydroxyl ~iber. As basic structures of the organic dyestuffs that may be used in particular those of the series of the azo, anthraquinone and phthalocyanine dyestuffs are suitable, the azo and phthalo-cyanine dyestuffs optionally being free from metal or con-taining metal. As reactive groups and precursors forming the~.e reaoti~e groups in an alkaline medium there may be mentioned, for example 9 epoxy groups, the ethylene lmide group, the vinyl group in a vinyl sulfone group or in an acrylic acid radical, beside~, tha B-~ulfato-ethyl sulfone group or the B-chloro-ethyl sulfone group. For these processes, use may also be made of derivatives of the t~trafluoro~cyclobutyl series, for example, that of the tetrafluoro-cyclobutyl-acrylic acid.
As reactive substituents in reactive dyestuffs, there may be used those substances which can be split off easily and which leave an electrophilic radicalO As examples for substituents of this kind there may be mentioned ha~oge~ atoms in the following ring systems: Quinoxaline, triazine, pyr~midine, phthalazine, and pyrida~one. IJse may also be made of dyestuff3 having several reactive group~ of a different kind.
The alkali metal hydroxide solutions necessary for the f`ixation can be used in the amount usually applied for the dyeing with reactive dyest~ffs, in most cases from about 5 to 150 grams per liter of padding liquor. As alkaline compound~
f this type, there may be mentioned advantageously aqueous solutions of preferably sodium hydro~ide, also of potassium hydro~ide, corresponding to an alkallnity of between 30 and 4~ Bé.
29 0~ the liquid alkall metal sili¢ates (water glasses) to be _ ' , '` ' : '; . ' ' , '' ' ' ,. . '' ' ' ,' ~'' '' ... . ' '' ,` '' ' ,, ' , :' .
'.. ' ' : , I .
.
' ~, ' ' ~ '. ' `' ~ ' ' HOE 7~F 0~8 added to thc paddlng baths according to the in~ention proce~s, there may be menti.oned advantageously commercia~ ~odium ~ili cate9 . Preference i9 given to sodium silicates of an alkaline strength of from about 37 to about 60 Bé, corresponding to a SiO2 content o~ the aqueous solution of from about 27.2 to about 38,2 ~ by weight. The amount to be used depends on the alkaline strength of the alkali metal ~ilicate used, on the dyestuff con-centration, and on the type of dyestuff, and i9 generally in the range of from about 25 g to about 350 g, preferably about 50 g t~p 200 g, per liter of padding liquor.
. .. .. .
.. Examples for an advantageous arrangement o~ the apparatus to carry out the present invention have been shown by way of diagram by means of the fig~res 1 to 5 given below, the re~
ference numbers used having the meaning stated below.
EXPLA~ATION OF THE FIGURES:
1 web of material 2 treatment ~dwelling~ chamber w1th temperaturs and humidity control

3 . inlet ~lit~
3a outlet sllts

4 trough for the liquor pair of rollers of the padder, squee~ing apparatus, optionally with open-width stacking device 6 endless conveyor belts 2~
7 inclined material tank~ may also be in the for~ of a trough, boot, etc, 8 driv~n tra.n~port roller 9 guide rollers liquor intake 10a distributor for the liquor to inten~ify the ci.rculation in -- 8 ~

. , , . H0 74 ~ ~

, the trough with a pump main ll partition wall in the padding trough; the liquor may be fed according to the counter current principle at the zone where the goods leave the trough 12 steaming compartment 13 pair of roller~ as a seali~g device ~or ~light differences . .
in pressure as inlet and outlet for the ~steamin~ com-partment 14 dipping trough ~or the short pa~sage through the hot alkali metal silicate solution, to be heated, with liquvr intake heating elementq 16 slewing direction of the plaiting-down device (not sho~m here~.
The ~ollowing Examples serYe tv ill~lstrate the invention.
E X A M P ~ E 1 . :
A fabric made of spun rayon staple fibers waq padded by means of an aqueous dye liquor containing, per liter of liquor, 50 g of ~he dye~tu~ o~ th~ formula 02S ~N = N~ j CH

O-Sû3Na S03Na and beside~, 100 g/l of sodiu~ silicate of 49 Bé and 20 cc./l of ~odium hydroxide solut;ion of 38 B~
- (32.5 % b~ weight) 9 _ 9 _ , . . ': , , .' , , : . ' , '"., : ' ~ ; ` " ' ' ' . ' ~ , ' ' ' , , . " ' '. ' .' . '' . '' . ' , . ~ ' ,~' ' , - :
. ': ' " ' ' ' ' " ' ~
~' ' ~ ' ' ' . ' ' ;"' at a temperature of 35 C and with a dye liquor pick~up of 70 ~ (calculated on the weigh-t of the dry goods), and was sub~
~ sequently allowed to dwell in a plaited down state at 40 C~
; After a dwelling time of 10 minutes and the usual after-treatment of the dyeing, practically the same yield of fixed dyestuff wa3 obtained, as if this padding had been effected at room temperature (21 C) and the d~elling time, according to the known cold-dwelling method, had been 2 hours ~also at room temperature~.
The comparison of the ti.nctorial strength of the two dyeings, determined according to the colorimetric values, was 97 : 100.

. ~ . . . _ . .
A fabric made of mercerized cotton was padded by means o~
an aqueou~ dye liquor containing the same dyestuf~ a~ in - Example 1, in the same concentration~ and in the presence of 100 g/l of sodium silicate o~ 49 Bé and 30 cc./l of sodium hydroxide solution of 38 B~, at a temperature of 18C and with a dye liquor pick~up of 70 ~
~ weight, a~d was allowed to dwell for 5 minutes at the same temperature. Subsequently, the padded goods were treated during 10 seconds with a qodium sillcate sol~*ion at 95C.
After the usual after-treatment of the dyeing~ a ratio of the color yield of 97 ~ 100 was obtained, a~ compared against a dyeing ha~ing the usual color yield according to the pro~en pad ~hort~dwell process~ with a d~ellin.g time o~ 2 hour~ at room temperature~
If the dyeing prepared as has been mentioned nbove was 29 subsequently steamed for 10 seconds at a temperature of fron .

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103 to 105 C, after a dwelling time of 5 minutes at room temperature, the resulting dyeing was of the same inten~ity - (97 : 100). Howe~er, if in the present case the dwelling phase was ornitted and the fabric was steamed immediately after the padding process, at a temperature of from 1 o3 to 105C, dyeing~
were obtained which showed a markedly reduc:ed tinctorial strength. The tinctorial strength was then after a stea~ning time of 10 second~ 76 : 100 30 seconds 84 : 100 60 ~econds 84 : 100.
These measurements were performed by means of a Hardy spectrophotometer.
E X A M P L E~
3 g/l of the dyestuff of the formula O~ H-CO-CH~, 2$~

^ CH
1 2 - .
OSO ~jH

were padded, toge-ther with 100 g/l o~ sodium silicate o~ 4g Bé and 20 cc./l of s~dium hydroxide solution of 38 Béf in the form of an aqueou~ dye liquor, on several 3pun rayon fabric~, at a temperature of 40C and with a dye liquor pick-up of 70 ~ by wei~ht, alld were allcw~d to dwell at the sarne temperatur~ for 10 or 20 minutes. Th0 yield obtai~ed following . . . ~ , ~ . ~ , , ,~ .
: : . . , ' ~ ' , :

HOE 71~F 0~8 ~:)S~ltil;~
the after-treatlnent of these d~eings corresponded to the color yield which can be obtained according to the known pad short dwell proc~ss. Even ~n exten~io~l of the dwelling time of the dyeing at 40 C to 40 minutes did ~ot alter the color with respect to its shad0 and depth.
E X A M P L E ~:
A mercerized cotton fabric was impreg~ated with an aqueo~s dye liquor containing 20 g~l of the dyestuff of the fori~ula -C-~~H2 Cl H03S~ N~ NH
- . 03H ~
~.

100 g/l of sodium silicate of 49 Bé and 30 cc, of sodium hydroxide solution of 38Bé, at a temperature of 23C, and was allowed to dwell, in a plaited-down stata, for 5 minutes at this temperature. In an analogous manner, a s~cond padding wa~
treated~ after a dwelling time of 5 minutes, during 10 seconds with saturated steam at a temparature of 105Co ~he color yields obtalned of the two dyeings after the subsequent treatment (thorougk rinsing and removing of the unfixed dyestu~f pro-portion) were compared with each other, and the same depth of shade was found to be there.
E X A M P L E 5: -. __ An aqueous dye liquor containing 50 g/l of the dye~tuff of CU` ~ ~ 2 ~ ~So2~E2~cH2-o~o~H ~2 29 \1S03~ ]2 (cu - Pc - = copper phthalocyanine) ~ 12 ---, : , . - .

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i5J~
100 g/l of sodium silicate of 49 Be and 30 cc./l of sodium hydroxide solution of 38 Bél was padded on a mercerized cotton fabric at a t~mperature o~ 22C ~nd with a dye liquor pick-up of 70 ~ by weight. ~ollowing a dwelling time o~ the padding of 10 minutes, the goods were steamed for 10 seconds at a temperature of from 103 to 105 C. After the usual subsequent treatment, a color yield o~ the dyeing thus produced was ob-tained which had a ratio o~ 97 : 100, as compared against a dyeing thàt had been allowed to dwoll over night at room temperature~ according to the pad dwell process.
When the padding prepared according to the above mentioned method was allowed to dwell ~or 10 minuteq at roo~ temperature and was subsequently dipped for 10 seconds into a solution of sodium silicate of 95C 9 a dyein~ wa~ obtained which had ~he same depth of shade. By extending the dwelling time at room t~mperature to 20 minutes, the color yield of this dyeing could even be inc~eased by 5 ~.
HoweYer, i~ the ~oods were padded with the same dyestuff and the chemical substances mentioned above 9 a~d if this padding wa~ steamed immediatel~, without dwelling t me, i.e.
according to tha wet-steaming process, dyeings sho~Jing a markedly reduced tinctorial strength ~ould be obtalned, even after a steaming time of 30 seconds.
The tinctorial strength after 10 second~ of steaming was 44 5 100, and afte~ 30 seconds of steaming, 76 : lOOo E X A M P L E 6:
.
Instead of the dyestu~ mentioned in E~ample 5, an aqueous dye liquor containing 50 g/l of the dyestuff of the formula . ,. .: ,, :: , ,, ~ . ~

, . . . ~ ' , " ' ~' ' ' :

~IOI~ 74 /~
Z

C~

~3~HO NX--C~~N-N~ ~ . ~IH_~_ HO S/~\ ~\SO H \~

was used in this case, the other conditions being unchsnged.
After the padding had been all~wed to dwell ror 1 o mimlteR
at r~om temperature, it was dipped for 10 seconds into a solution of ~odium silicate of 95C. The color.yield that could be obtained with this dyeing wa~ comparable to that obtained according to other dyeing methods.
X A M P L E 7:
When for the dyeing per~`ormed by way of the padding process according to Example 5 the same a~ount of the dyestu~f of formula SO H
~i-N=N~ CH
H0~3S~O-CH2-t~H2-02s~ N~
:~0 C~

S03~I
was used, and the goods were dyed according to the conditions mentioned in the ~ald Example, a good color ylcld was obtained after a dwelling time of 20 minuteY at room temperature and a sub~equent treatment of the padding during 10 seconds in a sodium ~ilicate solution at 95C.
I~ X .~ _ .
29 An aqueou~ dye liquor cont~inillg 30 g per llter o~ thie 14 _ :
-.

: " ''': . :: . .' '::'.': ': - .': : :: :. . .: ,: : ' . ,; . ' : . ' , , .

. H0~ ~ ~ 0~8 -~05~ 2 dyestuff of the formula ~03H OH
N - N ~ 2~2 NH-CO-CH_CH- I--b-CH3 . S03H ~I H
a~ well as 100 g o-f sodium silicate of 48 Bé and 30 cc. of sodium hydroxide solution (3205 ~) was padded on a mercerized cotton fabric at a temperature of 40C and wi-th a dye liquor pick-up of 70 ~ by w~ight. After a dwelling time of 10 minutes - 10 at a temperature of 40C, the goods were Rteamed for 30 seconds at a temperature of from 103 to 105 C. The depth of ~hade obtained after the subsequent treatment wa$ compared with a dyeing that had been steamed at a temperature of from 103 to 105 C for 30 seconds, without dwelling at 40 C immediately after the paddingO The ratio of the tinctorial strength was 100 s 86 in favor o~ the process incl`uding the dwelling pha~e~
E X A M P L E 9:
. A knit fabric mad~ ~rom bleached cotton w~s padded at room temparature 5 with a d~e liquor pick-up of 70 ~ by weight, by means of an aqueous dye liquor co~taining 50 g/l of ~he dyestuff of the formula SO H ~03 N=N~
S03H O~I

100 g/l of sodium silicate o~ 4~ Bé and 40 cco/l of sodium B h~dro~ide solution of ~ B~ This padding was now allowed 29 to dwell for 2 hours at room temperattlre. In allother ca~e, 15 ~

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HOE 74/~ 038 the padded goods were steamed for 10 seconds at a temperature of from 103 to 105C, ~ollowing a dwelling time o~ 5 minutes at a temperature of from 30 to 40C.
After the usual afte~treatr~ent, the same depth of shade was obtained in each case.

50 g/l of the dyestuff of the for~ula ',~
~03~I _ 0~3[ NH - CO--~,~ S02-CH=~H2 03~03 were padded ln the form of an aqueous dye liquor, together with 100 g/l of sodium silicate of 49 Bé and 30 cc./l of sodium hydroxide solution of 38 Bé9 at a temperature of 40 C, vn a mercerized cotton fabric~ and .the padding was allowed to dwell for 10 minutes at a temperature of 40 C. S~bsequently, the fabric was dipped for 10 seconds into a sodium silicate solution of 95 C. When, however, in the present case the padding and dwelling were perfo.rmed at room temperature ~21C), a tinctorial strength of 100 ; 96 was obtained after the usual a~ter-treatment. However, when the padded goods were dipped immediatel~ into a hot sodium silicate solution for 10 and 30 seconds without dwelling time, the tinctorial strength was markedly reduced (68 ~ 100).
-

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A continuous process for dyeing of flat textile material composed of cellulose fibers or of a mixture of cellulose and synthetic fibers by means of a reactive dyestuff, which process comprises padding, at a temperature of from 20 to 80°C, the textile material with a padding liquor which is an aqueous solution of at least one reactive dyestuff, about 25 to about 350 grams per liter of padding liquor of a liquid alkali metal silicate of from 37 to 60°B?
and about 5 to 150 grams per liter of padding liquor of an aqueous alkali metal hydroxide of from 30 to 45°B?, the composition of the padding liquor being sub-ject to the requirement that the weight ratio of alkali metal silicate to alkali metal hydroxide is in the range of from 1:0.1 to 1:0.5, placing the pad-ded textile material in a dwelling chamber, exposing the textile material in cuttled-up or opened-out condition in the chamber to humid heat in the above-mentioned temperature range for from 5 to 30 minutes, the temperature in the dwelling chamber being controlled by means of infrared radiators and steam injection, so that the dyestuff is fixed by the dwelling operation, and con-tinuously removing the textile material from the dwelling chamber.

2. A process as claimed in Claim 1, wherein the fixation of slowly re-acting dyestuffs is completed by a short steaming process following the dwell-ing phase.

3. A process as claimed in Claim 1, wherein the fixation of slowly re-acting dyestuffs is completed by a short dipping of the goods into a hot sodium silicate solution (water glass).

4. A process as claimed in Claim 1, wherein the padding liquor is pre-heated, or the padding liquor is applied onto the web in a trough.

5. A process as claimed in Claim 4 wherein the trough is heated.

6. A process as claimed in Claim 1, wherein padding is also effected within the dwelling chamber that is pre-heated.