US 3873265 A
A process for the simultaneous dyeing and crease-proof finishing of textile material consisting of cellulose fibers or blends of cellulose fibers and polyester fibers by impregnating the textile material with an aqueous bath containing a reactive or vat dyestuff or a disperse dyestuff and a reactive or vat dyestuff, N-methylol-acrylamide or N,N-dimethylol-methyl-bis-acrylamide or an ether thereof with an alkanol containing 1 to 3 carbon atoms as well as an acid catalyst, dry heating the material to condense the N-methylol group of the synthetic resin and optionally fixing the disperse dyestuff at the same time, and in a second fixation step simultaneously fixing the reactive or vat dyestuff and the ambivalent cross-linking agent in an alkaline medium, and then after-treating the material by washing operations.
Description (OCR text may contain errors)
United States Patent [191 Kleber et al.
[ Mar. 25, 1975 VAT OR REACTIVE DYES OR MIXTURES THEREOF AND ACRYLAMIDE OR METHYLENE BlS-ACRYL-AMIDE IN ALKALINE CROSSLllNKlNG AND DYEING  Inventors: Rolf Kleber, Neu-Isenburg; Otto Smerz, Kelkheim, Taunus; Giinther Trapp, Frankfurt, Main, all of Germany  Assignee: Hoechst Aktiengesellschaft, Frankfurt, Main, Germany  Filed: Feb. 2, 1973 ] Appl. No.: 328,941
Wilhelm .r 8/84 3,246,946 4/l966 Gardon 8/l7 X 3,265,461 8/1966 Luetzel 23/84 3510247 5/1970 Tesoro 8/17 X Primary Examiner Donald Levy Attorney, Agent, or Firm-Connolly '& Hurtz  ABSTRACT A process for the simultaneous dyeing and creaseproof finishing of textile material consisting of cellulose fibers or blends of cellulose fibers and polyester fibers by impregnating the textile material with an aqueous bath containing a reactive or vat dyestuff or a disperse dyestuff and a reactive or vat dyestuff, N- methylol-acrylamide or N,N-dimethylol-methyl-bisacrylamide or an ether thereof with an alkanol containing 1 to 3 carbon atoms as well as an acid catalyst, dry heating the material to condense the N-methylol group of the synthetic resin and optionally fixing the disperse dyestuff at the same time, and in a second fixation step simultaneously fixing the reactive or vat dyestuff and the ambivalent crosslinking agent in an alkaline medium, and then after-treating the material by washing operations.
6 Claims, N0 Drawings VAT OR REACTIVE DYES OR MIXTURES THEREOF AND ACRYLAMIDE OR METHYLENE BIS-ACRYLAMIDE IN ALKALINE CROSSLINKING AND DYEING A likewise wide-spread practice is the crease proofing of textile material containing cellulose fibers by means of products which impart to these textiles a reduced tendency to creasing and an increased selfsmoothing effect.
In practice, these two finishing operations have so far been carried out separately one after the other in such a manner that the textile material is first dyed and then crease-proofed.
The two finishing operations had also to be performed separately for chemical reasons, since the fixation of the dyes is controlled by alkaline agents, whereas the usual creaseproof finish is initiated by acid yielding agents.
Belgian Pat. No. 616,368 proposes simultaneously to apply crease-proofing products, hardening catalysts and vinylsulfone or sulfonamide dyes giving an alkaline reaction onto the textile material consisting entirely or predominantly of natural or regenerated cellulose. By means of a dry condensation method, the creaseproofing agent is fixed and the dye which is not sensitive to acids is fixed in a second step under alkaline conditions.
According to this method, however, only the separate application of the crease-proofing agent and a drying operation are dispensed with. The hardening of the crease-proofing agent and the alkaline fixation of the reactive dye continue to be carried out in separate steps.
lt has also not been possible to obtain optimum fastness properties of the dyeings and prints, since the dye portion which has not reacted with the fiber was only difficult to be removed by washing but was retained by the synthetic resin, so that, in the end, the fastness properties were not determined by a fast" dye-fiber linkage but by the fastness to washing of the synthetic resin with the dye portionincorporated therewith.
Similar methods are also disclosed in U.S. Pat. No. 3,054,699 and in the two British Pat, Nos. 846,505 and 884.043. According to those methods, the textile material is treated with aqueous solutions containing a resinifying component, an acid yielding agent and dyes having a halogen atom or another reactive group and being therefore capable of reacting with the synthetic resin or the fiber in an acid medium at an elevated temperature.
In this case, too, it showed that the reactive dye groups do not at all react with the cellulose under the indicated process conditions but that the fixation of the dyes is exclusively brought about by the synthetic resin. Thus, those methods do neither allow optimum fastness properties to be obtained but these properties also depend on the fastness of the synthetic resin to washing.
Another disadvantage of all those known methods resides in the use of synthetic resins capable of being condensed in an acid medium, which merely influence the dry-state crease proof properties of the fabrics finished therewith.
This led, for the first time in the process of British Pat, No. 982,255, to the simultaneous use of two crease-proofing agents, the first one being a usual resin capable of being condensed in an acid medium, of the N-methylol-urea type, and the second one a divinylsulfone derivative caused to react only during a steaming process in an alkaline medium. In this manner, not only dry-state crease-proof properties but also excellent wet-state crease-proof properties are obtained. Owing to the toxicity of the divinyl-sulfones, however, this method could not gain ground in practice. Another disadvantage thereof is that the dry-state and wet-state crease-proof properties require two different resin types.
However, U.S. Pat. No. 2,837,511 and German Offenlegungsschrift No. 1,940,799 disclose methods which afford both dry-state and wet-state crease-proof effects using only one compound, a so-called ambivalent crease-proofing agent", for the high-grade finishing of textile materials containing cellulose fibers. These ambivalent cross-linking agents, for example N- methylol-acrylamide or N-methylol-methylene-bisacrylamide, are condensed with dry heat in usual manner, after application with acid yielding agents, with a reaction of the N-methylol groups and then linked, in swollen state, with the cellulose in a second separate step in an alkaline medium during a dwell process. This ambivalent cross-linking reaction imparts, in addition to excellent dry-state crease-proof'effects, also outstanding wet-state crease-proof'effects. A textile material cross-linked with ambivalent agents shows drip and spin-dry effects, i.e. a self-smoothing capacity that cannot be achieved by the conventional dry cross-linking reaction. In spite of the excellent dry-state and wetstate crease-proof behavior, however, those methods using an ambivalent high-grade finishing agent could neither succeed so far in practice for economic reasons, owing to the discontinuous working method.
According to the process of the present invention, it is now possible to pool the advantages of the ambivalent cross-linking reaction as illustrated above and the well known alkaline fixation methods for reactive and vat dyes respectively, the so-called two-phase processes, by combining the alkaline developing steps present in the two finishing operations in one step.
This invention therefore provides a process for the simultaneous dyeing and high-grade finishing of textile materials consisting of cellulose fibers or of blends of cellulose fibers and polyester fibers by a joint fixation of dyes and synthetic resin precondensates on textiles, which process comprises exposing the textile material, that has been impregnated with an aqueous bath containing an ambivalent cross-linking agent and an acid catalyst and a reactive or vat dyestuff as well as, where required a disperse dyestuff, and optionally dried at a temperature below the reaction temperature of the N- methylol groups of the cross-linking agent, to dry heat in a first fixation step to bring about acid condensation of the N-methylol groups of the cross-linking agent and, where required, simultaneously fixing the disperse dyestuff and subsequently fixing, in a second fixation step, the reactive or vat dyestuff at the same time with the ambivalent cross-linking agent in an alkaline medium, and finally carrying out the after-treatment of the textile by a washing operation preferably performed stepwise, advantageously in acid baths.
According to the process of the invention, the condensation of the N-methylol groups and the simultaneous fixation of the disperse dyestuffs are brought about by means of dry heat during the first fixation step and the alkaline cross-linking reaction of the ambiva lent resin and the simultaneous development of the vat dyestuff or the fixation of the reactive dyestuff are performed in an alkaline medium during the second fixation step under the usual conditions.
Surprisingly, it was found that, when ambivalent cross-linking agents of the invention are used, the fast ness properties, i.e. the fastness to light, rubbing and washing, of the dyeings are substantially better than those obtained when a normal crease-proofing agent, for example, of the type of an N-methylol-ethyleneurea, N-methylol-glyoxal-urea or other cross-linking agents, is used.
Compared to the conventional method comprising subsequent high-grade finishing, this novel process for the dyeing with reactive or vat dyes on cellulose fiber material can dispense with a pad-dyeing operation,
a washing operation,
two drying operations and an alkaline wet treatment; when blended fabrics made from polyester and cellulose fibers are dyed with reactive or vat dyes and disperse dyes, all the operations required for the highgrade finishing with ambivalent cross-linking agents can be dispensed with, that is a pad-dyeing operation,
a washing operation, 1
two drying operations,
an alkaline wet treatment and a thermofixing process.
The working mode of the novel process to be applied to cellulose fibers and to polyester/cellulose fiber blends is hereinafter illustrated in principle:
1. Finishing of pure cellulose fiber textile material 1. One-bath application of reactive or vat dyes and ambivalent cross-linking agents on the basis of N- methylol acrylamide or N,N-dimethylol-methylene-bisacrylamide and an acid catalyst by pad-dyeing, impregnation or spraying onto the textile material to be finished.
2. Optional drying at temperatures of up to about 110C, preferably at 90 110C.
3. Condensation performed by exposing the material at open width to dry heat for half a minute to minutes at a temperature of from about 140 to 240C, preferably from 150 to 160C.
4. Alkaline wet treatment at a pH-value exceeding 10 for the fixation of the dyes and simultaneous crosslinking of the ambivalent cross-linking agent.
5. Washing and soaping 6. Drying lf reactive dyes are used alone, the alkaline wet treatment may preferably be carried out according to the so-called cold-dwell method at room temperature, ie at about 10 to 30C, over a period of about 2 to 100 hours, using about 8 to 150 g/l of sodium or potassium hydroxide. The vat dyes, however, are preferably de veloped under steaming conditions also in the presence of an alkali metal hydroxide solution for about 10 seconds to 30 minutes at elevated temperatures of up to about C. In both cases, the cross-linking of the ambivalent creaseproofing agent is brought about simultaneously. I
The material is finally washed, where required oxi dized, soaped and dried.
ll. Finishing of textile materials made from polyester/- cellulose fiber blends For the dyeing of textile materials made from polyester/cellulose fiber blends, combinations of disperse dyes with reactive or vat dyes have proved to be especially suitable in practice. To that effect, a mixture of disperse dyes and reactive or vat dyes are jointly applied to the material to be dyed, the material is then dried and thermofixed at 240C for the fixation of the disperse dye on the polyester fiber portion, Fixation of the reactive or vat dyes on the cellulose fiber portion is subsequently brought about as disclosed sub 1. The following working principle has therefore to be observed for applying the process of the invention to such fiber blends:
l. One-bath application of the disperse dyes as well as of the reactive or vat dyes and of the ambivalent cross-linking agent and the acid catalyst (as sub 1).
2. Optional drying at temperatures of up to about 1 10C, preferably of 90 to 1 10C.
3. Thermofixation of the disperse dyes and simultaneous condensation of the N-methylol groups by exposing the material to dry heat for about half a minute to 5 minutes at about 180 240C.
4. Alkaline wet treatment for the fixation of the reactive or vat dyes with simultaneous cross-linking of the ambivalent crease-proofing agent.
5. Washing and soaping 6. Drying Special attention has to be paid to a careful aftertreatment of the dyed and finished textile materials, since it is difficult entirely to wash out the excess disperse dye portion upon the dyeing of blended fabrics of polyester and cellulose fibers with these dyestuff mixtures.
It is, however, much more difficult to perform a washing operation on blended fabrics having a high grade finish, since the disperse dye portion moreover tends to preferably soiling the applied synthetic resins during the washing operation, which causes additional dulling and soiling.
It was now found that this soiling caused by the disperse dye portion only results in great difficulties in an alkaline pH-range but that it can largely beavoided by carrying out the individual steps of the washing operation at the end of the finishing method in more or less acid liquors.
Optimum results can, for example, be obtained in a continuous method in an open-width washing machine having at least 7 compartments according to the following method:
1. Rinsing with cold water with overflow 2. Rinsing with cold water with addition of acetic acid 3. Soaping at about 50C using, for example,
1 g/l of an oxyethylated castor oil and 0.5 cc./l of 50 /r acetic acid.
4. Soaping at about 80C, using for example 0.5 g/l of an oxyethylated castor oil,
0.5 g/l of a nonylphenol-decaglycol ether and 0.5 g/l of mono-sodium phosphate.
5. Soaping at the boil, using for example 0.5 g/l of an exyethylated castor oil and 2 g/l of acid sodium hexametaphosphate.
6. Rinsing with hot water.
7. Rinsing with cold water.
As oxyethylated castor oil, there are preferably used a reaction product of about 32 mols of ethylene oxide with 1 mol of castor oil or, instead, butane-diol(1,4)- pentadecaglycol ether-dioleyl ester or similar products having slightly differing ethylene oxide portions.
This stepwise after-treatment allows not only optimum dyeings to be obtained without any deterioration of the drystate and wet-state crease-proof behavior, but also the usual fastness properties, for example fastness to wet processing, washing and perspiration, correspond, to a large extent, to the standards of dyeings on blended fabrics which have no high-grade finish.
The process of the invention can be carried out without restriction with all mixtures of disperse and reactive or vat dyes. The material is provided with a good selfsmoothing capacity which is very important, for example for blended fabrics of polyester fibers and cotton (drip-dry effect of about 4.5 according to Monsanto) and which cannot be achieved by a pure dry cross linking operation.
It is true that mono-bath application of disperse dyes and resins (dimethylol-ethylene-urea, dimethylolglyoxal-urea) for the simultaneous dyeing and finishing of synthetic fibers has already been disclosed in the art (cf. Textil-Rundschau St. Gallen, 1961, 16, pages 713 to 725), but those methods could as yet not gain ground in practice, since their results, though satisfactory from the coloristic point of view as far as fastness properties and color yield are concerned, showed some disadvantages as to the crease-proof property. Thus, owing to the high temperatures of the thermofixation process, a so-called thermosoling rigidity of the finished materials cannot be avoided. Although this can somewhat be eased by varying the fixation conditions and by means of softening additives, it will lead to an untolerable hardening, especially on thin fabrics. The creaseproof effects achieved according to those methods correspond to those obtained by usual dry crosslinking reactions. The good self-smoothing notes of, for example, 4.5 according to Monsanto (cf. AATCC Standard Test Method 88-1961) and wet-state crease angles according to Tootal of 270 to 300 (warp and weft) (cf. SVF-Fachorgan fuer Textilveredlung 12 (1957), page 754), as they are obtained with the ambivalent cross-linking agents in the combination process of the invention, cannot be achieved according to the methods disclosed in the art. According to the process of the invention, the feel of the goods is substantially softer and more pleasant than achieved by known methods. The combination of ambivalent cross-linking, joint fixation with disperse, reactive or vat dyes is optimum as far the economy ofthe dyeing and finishing operations is concerned.
The process of the invention for the joint fixation of ambivalent crease-proofing products and dyes on textile materials can be applied to known cellulosic fibers and blends of polyester fibers and cellulosic fibers. The cellulosic fibers may be natural fibers, such as flax, hemp, linen, cotton, or regenerated fibers, such as viscose, spun rayon or modal fibers.
The process of the invention may be operated with dyestuffs chosen from all the known reactive dyestuff systems, for example on the basis of monochlorotriazine, dichlorotriazine, trichloropyrimidine, vinylsulfone, vinylsulfonamide, dichloro-quinoxaline and acrylamide dyestuffs, preferably those reactive dyes which are stable under the conditions of a dry crosslinking reaction initiated by an acid catalyst. As vat dyes, there may be used dyestuffs of the type of monoand polyazo dyestuffs, of indigo, thio-indigo and the corresponding derivatives, of the anthraquinone dyestuffs having one or more anthraquinone nuclei, of indanthrone, flavanthrone and anthraquinone carbazole, of the acridones, (thio-) oxanthrones, pyranthrones, anthrathrones and anthrinides as well as of the dibenzanthrone and dibenzopyrene quinone.
As ambivalent cross-linking agents, there are used the products known from German Offenlegungsschrift No. 1,940,799 and US. Pat. No. 2,837,51 1, namely N- methylol compounds of acrylamide or of methylenebis-acrylamide or ethers of these methylol compounds with lower alkanols containing 1 to 3 carbon atoms. These ambivalent cross-linking agents are employed in amounts usual for the high-grade finish of textile materials of from about 1 to 25 percent by weight, preferably from 2 to 15 percent by weight, calculated on the textile material to be finished.
In addition to these ambivalent cross-linking agents, other hardenable finishing agents containing N- methylol groups may optionally be used for the process of the invention. As such finishing agents, there are mentioned, above all, methylol compounds of urea or urea derivatives as well as of the cyclic compounds, such as ethylene urea, l,3-propylene urea, melamine and derivatives thereof as well as methylol compounds of monoand dicarbamic acid esters, moreover the ethers of these methylol compounds with lower alkanols. These conventional hardenable finishing agents may be added in amounts of up to about percent by weight, calculated on the amount used of the ambivalent cross-linking agent.-
The acid catalysts chosen (often also referred to as hardening or acetalyzing catalysts) are substances currently used for this purpose in the high-grade finishing practice. They may be strong or medium-strong organic or inorganic acids, for example monochloracetic acid, trichloracetic acid, tartaric acid, citric acid, oxalic acid, glycolic acid, phosphoric acid, hydrochloric acid or sulfuric acid. Compounds having a latent acidity, which develop acid underthe conditions of the first fixation step, for example salts of medium-strong or strong acids with ammonia, amines or polyvalent metals, such as ammonium chloride, ammonium sulfate, ammonium phosphate, ethanol-ammonium chloride, magnesium chloride, zinc chloride, zinc nitrate. aluminium chloride, zinc fluorborate and zirconium oxychloride. The acid catalysts are used in the usual amounts which depend especially on the amount of the ambivalent cross-linking agent used and on the other hardenable N-methylol compounds that may also be used. It generally ranges from about 0.3 to 30 percent by weight, preferably from to 25 percent by weight, calculated on the amount of the total of cross-linking agent added.
According to the process of the invention, additives, such as softeners, polyethylene dispersions, waterrepellants and other normally used products and adjuvents can be used without adversely affecting the coloristic and finish effects.
The following Examples illustrate the invention, the parts and percentages being by weight unless stated otherwise. The Colour lndex numbers indicated to characterize the dyestuffs have been taken from the 2nd edition 1956 and from the Supplement of 1963.
EXAMPLE 1 a. A bleached cotton popelin material is padded with an aqueous liquor containing, per liter,
40 g of the reactive dyestuff C.I. No. 61200,
120 g of a 50 aqueous solution of dimethylolethylene-urea,
120 g of a 30 aqueous solution of dimethylolmethylene-bis-acrylamide and 25 g of hexahydrate of magnesium chloride.
The liquor pick-up is 60 The fabric is dried at 100 l C in a laboratory-scale jet drier and then heated to 155C for 4 minutes.
The fabric is then impregnated on a two-roller padding machine at room temperature and at a liquor pickup of 70 /1 with an aqueous liquor containing, per liter,
200 g of sodium chloride,
30 cc. of sodium hydroxide solution (38Be) and 10 g of calcined sodium carbonate.
The goods are wound up, wrapped in a plastic film and stored for 10 to 12 hours at room temperature. Then it is washed with cold water, neutralized by means of acetic acid, rinsed at 70 80C with warm water, soaped at the boil with a liquor containing 2 g/l of wetting agent, and rinsed carefully.
The cotton fabric thus treated has a brilliant blue shade and very good fastness properties and optimum wet and dry-state crease angles. The results obtained by testing the crease-proof effects are compiled in Table l.
b. For comparisons sake, another sample of the cot' ton popelin used sub (a) was dyed according to Belgian Pat. No. 616,368 with the reactive dyestuff C]. No. 61,200 and then given a high-grade finish, using 150 g/l of a 50 7r aqueous solution of dimethylol-ethylene-urea without an ambivalent cross-linking agent.
A comparison of the finish obtained according to (a) and (b) shows that the fabrics finished according to (a) with ambivalent cross-linking agents exhibit, in addition to substantially better crease-proof effects, distinctly improved fastness to rubbing in dry and wet state as well as fastness to washing at the boil and perspiration (cf. Table 1).
EXAMPLE 2 a. A batiste fabric made of a blend of cotton and polyester fibers (50:50), having a weight of 100 g per square meter, is treated with an aqueous padding liquor containing, per liter,
50 g of a dyestuff mixture of 66.7 parts of Disperse Yellow 5, C]. No. 12 790, and 33.3 parts of the reactive dyestuff obtained by coupling diazotized 6 chloro-3-amino 4-sulfobenzoic acid with the sulfuric acid ester of 1-(4-B-oxethyl-sulfonyl)-phenyl-3- methyl-S-pyrazolone, 200 g of a 60 aqueous solution of N-methylolacryl-amide and 30 g of hexahydrate of zinc nitrate and the pH of which has been adjusted to 3.5. The 1iquor pick-up is The fabric is then pre-dried first to a remaining moisture of 30 while passing it contact-free over a drier and then finished drying on a hotflue. 1t is finally exposed to dry heat at 200C for 20 seconds.
The goods are then padded at 20C and at a liquor pickup of 60 with an aqueous solution containing, per liter,
200 g of decahydrate of sodium sulfate and 200 cc. of sodium hydroxide solution (38Be), and then steamed for 25 seconds at 105C.
The fabric is carefully washed at a transport speed of 20 meters per minute on an open-width washing machine and dried as follows:
1. Rinsing with cold water with overflow;
2. Rinsing with cold water with addition of acetic acid;
3. Soaping at 50C with a solution containing, per 1iter,
10 g of a butane-diol( l,4)-pentadecaglycol etherdioleyl ester and 0.5 cc. of a 50 70 acetic acid;
4. Soaping at C with a solution containing, per liter,
0.5 g of a butane-diol-( l,4)-pentadecaglycol ctherdioleyl cster,
0.5 g of nonylphenol-decaglycol ether and 0.5 g of mono-sodium phosphate;
5. Soaping at the boil with a solution containing, per liter,
0.5 g of a butane-diol-(1,4)-pentadecaglycol etherdioleyl ester and 2.0 g of acid sodium hexametaphosphate',
6. Rinsing with hot water and 7. Rinsing with cold water.
A brilliant yellow tone-in-tone dyeing having excellent fastness properties and crease-proof effects is obtained.
b. For comparisons sake, another sample of the fabric used sub (a) was treated on a padding machine according to the art as cited in Textil-Rundschau", St. Gallen, 16/1961, page 713, sub (f), with the same dyestuff mixture as sub (a) and with 120 g per liter of a 50 aqueous solution of dimethylolethylene-urea and 5 g per-liter of hexahydrate of magnesium chloride and then thermofixed as sub (21), developed in an alkaline medium and finished as usual by rinsing, soaping and rinsing once more.
The results obtained upon a comparative test of the fabrics finished according to (a) and (b) clearly demonstrate the advantages of the goods finished according to the process of the invention according to (a), which moreover show a softer and more pleasant feel.
EXAMPLE 3 A fabric made from mercerized cotton popeline and having a weight of g per squaremeter is treated with an aqueous liquor containing, per liter.
20 g of lndanthrene Violet RH,C.1. No. 73,385.
350 g of a 60 aqueous solution of N- methylolacrylamide,
120 g of a 50 solution of dimethylol-propyleneurea and 40 g of hexahydrate of magnesium chloride. The fabric is squeezed to a weight increase of 65 The goods are heated to 160C for minutes to bring about drying and simultaneous condensation. After a treatment with an aqueous liquor containing, per liter,
90 g of formaldehyde-sulfoxylate, 90 cc. of sodium hydroxide solution (38Be) and 50 g of decahydrate of sodium sulfate, the fabric is steamed for 7 minutes at 102C. It is then rinsed, soaped hot, rinsed once more and dried.
A level dyeing having excellent fastness properties and, at the same time, a high se1f-smoothing effect is obtained (cf. Table 1).
TABLE 1 10 consisting of N-methylol-acrylamide, N,N- dimethylol-methylene-bis-acrylamide, and others thereof with an alkanol containing 1 to 3 carbon atoms, and an acid catalyst;
b. in a first fixation step, exposing the material in an acid medium to dry heat;
c. in a second fixation step, treating the textile material in an alkaline medium; and
d. finally, carrying out an after-treatment of the material by a washing operation.
2. A process as claimed in claim 1, wherein the impregnated textile material is dried before the first fixation step at a temperature below the reaction temperature of the N-methylol groups of the ambivalent crosslinking agent.
(Crease-proof effects) crease angle in wet crease angle in dry wash and wear state according to state according to according to l'ootal (warp weft) Monsanto Monsanto l Example untreated I90 I40 1 finished according to (a) 278 250 4.6 finished according to (b) 240 220 3.8 Example untreated 220 230 2 finished according to (a) 295 285 5 finished according to (b) 260 265 3.9 Example untreated 188 135 1 3 finished 278 256 4.5
l after a washing operation at 60C.
3. A process as claimed in claim 1, wherein the first fixation step is carried out for half a minute to 10 min utes at C to 240C.
4. A process as claimed in claim 1, wherein the alkaline fixation step is carried out at a pl-l-value exceeding 10.
5. A process as claimed in claim 1, wherein the aftertreatment is carried out in an acid washing liquor con taining an oxyethylated castor oil or the dioleylester of an oxyethylated butane-diol-( 1,4).
6. A process as claimed in claim 1, wherein the aftertreatment is carried out stepwise in acid baths.