US3086832A

US3086832A - Process for finishing dyeings

Info

Publication number: US3086832A
Authority: US
Priority date: 1958-03-21
Publication date: 1963-04-23
Anticipated expiration: 1980-04-23
Also published as: NL237316A; DE1099494B; FR1229837A; GB879356A

Description

3,086,832 PROCESS FOR FINISHING DYEENGS Richard Casty, Basel, Switzerland, assignor to Ciba (Iorporation, a corporation of Delaware No Drawing. Filed Mar. 13, 1959, Ser. No. 799,088 Claims priority, application Switzerland Mar. 21, 1958 Claims. (Cl. 8-54) It is known that cellulose fibers, such as cotton, can be dyed with advantage with dyestuffs which contain mobile reactive halogen atoms. It is also known that nitrogenous fibers, especially wool, can be dyed with the aforesaid dyestuffs in acid baths. However, the aforesaid dyestufis are only partially suitable for this purpose. Some of these dyestuflfs yield useful wool dyeings only in conjunction with certain assistants, which are hereinafter described. Generally, these dyestuffs have the disadvantage that they yield wool dyeings having unsatisfactory properties of wet fastness when the dyeing is carried out in the usual manner from an acid bath with or without one of the aforesaid additions. The properties of Wet fastness, for example, the fastness to washing or perspiration, leave something to be desired not so much with respect to change in tint as with respect to bleeding on to or soiling fibrous materials that are undyed or differently dyed. This invention provides a process which enables this disadvantage to be largely or completely overcome.

Thus, the invention is based on the observation that by raising the pH-value of the acid dyebath after the dyestufi has been absorbed by the fiber the properties of wet fastness in relation to bleeding can be very substantially improved. Accordingly, this invention provides a process for finishing dyeings which have been produced on nitrogenous fibers with dyestuffs which contain at least one mobile halogen atom, in acid baths, wherein, after the fibers have absorbed the desired quantity of dyestutf, the pH-value of the dyebath is raised above 6.

The process is applicable -to any nitrogenous fibers that have been dyed in the aforesaid manner, for example, silk or fibers of a polyarnide obtained from e-caprolactam or from adipic acid and hexamethylene diamine. However, the process is especially advantageous for W001 dyeings.

The dyestuffs with which the fibers are dyed must contain at least one mobile halogen atom, that is to say a halogen atom capable of reacting with the fibrous material, for example, a bromine atom or advantageously a chlorine atom. In other respects the dyestulfs may belong to a very wide variety of classes of dyestuffs, for example, there may be mentioned stilbene dyestufifs, nitrodyestuffs, triphenylmethane dyestuffs, water-soluble phthalocyanine dyestuffs and above all acid anthraquinone or azo-dyestufis, including metal-free and metallizable or metalliferous monoor poly-azo-dyestutl's. In order that they can be dyed from acid baths, the dyestulfs must be soluble in such baths and therefore usually contain at least one sulfonic acid group.

The mobile halogen atom may be bound, for example, to the acyl radical of an acid containing at least one acid group of the constitution JLOH for example, to an acyl radical of cyanuric acid or of an aliphatic carboxylic acid. In the case of the acyl aent 3,086,832 Patented Apr. 23, 1963 in which X represents an alkyl, aryl, aralkyl, alkylmercapto or arylmercapto group, or more especially an amino group which may be substituted or a hydroxyl group which is advantageously substituted; or a dichlorotriazine radical.

The halogen-containing acyl radicals of aliphatic carboxylic acids advantageously contain few carbon atoms, for example, two or three carbon atoms. As examples there may be mentioned the chloracetyl group, the ocor fi-chloropropionyl group and above all the aIB-diClIllOIO- propionyl group.

A large number of such dyestuffs is known or can be made by methods in themselves known, for example, from dyestuff components which contain the mobile halogen atoms, or by introducing by methods in themselves known radicals which contain mobile halogen atoms. Thus, by reacting an azo-dyestufr' or anthraquinone dyestuff which contains a reactive hydroxy, mercapto or preferably a free amino group with chloracetyl chloride, ,8bromoor fl-c'hloro-propionyl chloride, chloropropionic anhydride or azfl-dichloropropionie acid chloride or anhydride, cyanuric chloride or a primary condensation product of cyanuric chloride which contains two chlorine atoms and, instead of the third chlorine atom, a free amino group or an organic radical, there are obtained valuable condensation products, which contain a mobile chlorine or bromine atom and are suitable for use in the process of this invention As stated above, some of these dyestuffs, especially those containing three or more than three sulfonic acid groups, when used for dyeing wool from acid baths yield weak, unlevel (skippery), practically useless dyeings. However, valuable level dyeings are produced with the aforesaid dyestuffs by dyeing wool in an aqueous bath in the presence of a compound which contains at least one basic nitrogen atom, to which is bound at least one radical containing a polyglycol ether chain, and the molecule contains at least three l I groups (advantageously --CH -CH O groups) and at least four carbon atoms that do not belong to such a group. In finishing dyeings by the process of this invention it is therefore of advantage, when these disadvantageous dyestuffs are used for dyeing, to add a nitrogen compound of the above constitution.

'Ihe-se nitrogen compounds apart from the fact that they must possess the characteristics defined above, may have a wide variety of constitutions. It will sufiice herein to mention, as compounds especially suitable for this purpose, nitrogen compounds of the formula Hr-CHr-mrd in which R represents an advantageously unbranched aliphatic hydrocarbon radical containing at least 12 and preferably 16-20, carbon atoms, m and n each represents the whole number 1 or 2, and p, q and r each represents a whole number and the sum of p+q+(m-1)(r-1) is at least 3, for example, 6 to 16.

Instead of the compounds containing free hydroxyalkyl groups, there may be used as assistants in the present process esters of these hydroxyalkyl-compounds with polybasic acids, for example, phosphoricacid'or sulfuric acid, or water-soluble salts of these acids, for example, alkali metal saltsor saltswith ammonia or amines. Furthermore, in some cases skippery dyeings can be avoided by adding to the dyebath a cation-active compound, for example, cetyltrimethylammonium bromide, and also advantageously a polyglycol ether of an aliphatic alcohol of high molecular weight.

The dyeings with which the present process is concerned are dyeings that have been produced in acid baths, and for-this purpose the dyeing is advantageously carried out in an acetic acid medium, that is to say, the dyebath has an acetic acid reaction at least at the beginning of the dyeing operation. It is therefore of advantage to incorporate in the dyebath advantageously at the beginning of the dyeing operation at least sufficient acetieacid to produce the desired pH-value, account being taken of the fact that both the fibrous metal and the dyestuif which is usually present in. the form of an alkali metal salt consume a certain amount of acid. In general it is of advantage to add sodium sulfate to the dyebath.

' As is usual in dyeing nitrogenous fibers, especially wool, the dyeing is carried out'ata raised temperature, advantageously by commencing the dyeing process proper at about 50 C. to 80 C., and then heating the dyebath to the boiling temperature and continuing the process and completing itat that temperature. However, it has been found that in dyeing wool by the process of this invention it is not necessary to work atthe boiling temperature of the dyebath or very close to that temperature. Usually equally good results are obtained by carrying outthe dyeing process at a temperature distinctly below the boiling temperature, for example, at a temperature within the rangeof 80 C. to 90 C. When the dyeing is carried out in the presence of one of the aforesaid nitrogenous compounds, it is of advantage to enter the goods'into the bath, which contains the acid andthe assistant, that is to say the nitrogenous compound, and-if desired sodihmsulfate, at room temperature or at most a moderately raised temperature, then to raise the temperature of the bath and when the bath is hot, for example, at 50 C; to 80 C., to add the dyestufiin the form ofan aqueous solution. If desired, the dyeing may be carried out in a suitable apparatus at a temperature above 100 C., at about 107 C.

The pH-value of the bath is then raised above 6. In order to raise the pH-value of the bath almost any watersoluble compound of alkaline reaction can be used.

11 -0 O-NH However, in order to avoiddamagingthe fibers, especially in the case of wooldyeings, it is of advantage; to add a compound of alkaline reaction of which. an excesscan be added without raisingv the pH value higher than about 9, and advantageously the pH is-raised to a value within therange of 6.5 to 8.5. For this purpose it is of advantage to use nitrogenous bases, for example, amines such as ethanolamines. -In some cases ammonia is quite suitable, and especially suitable is hexamethylene tetramine.

Alkali metal ortho-phosphates or polyphosphates or bicarbonates are also of advantage.

Only a relatively short time is required for the treatment at the higher pH value, for example, about 10-30 minutes. It is preferably carried out at about the same temperature as that at which dyeing was carried out. For example, the dyebath may be maintained at the boiling temperature during the after-treatment, or the temperature may be allowed to fall slightly, for example, by discontinuing the supply of heat after the pH-value has been raised. Finally, the dyeings can be rinsed in the usual manner with warm and/ or cold water and dried.

When dyeing is carried out in an acid bath in the presence of a nitrogenous compound of the kind referred to above, a considerable amount of the nitrogen compound remains adhering to the wool after rinsing and drying. This may cause a change in the feel of the wool, a change in the behaviour of wool piece goods in. after-dressing treatments, or, due to the increased slip. of the material, may alfect the spinning properties of loose, wool or combed wool, and a change in the speed of drying of the wet wool is frequently observed. These usually undesirable phenomena are avoided by raising the pH-value because the nitrogenous compounds are retained. by thewool only under acid conditions, whereas they remain in solution in neutral baths or return to the dyebathwhen the wool surface is neutralized.

The process of this invention is especially suitable for dyeing mixtures of nitrogenous fibers with cellulose fibers, for example, so-called half-wool, since it can. be carried out in a 2-stage process in a single bath. The wool com:-

ponent of themixed fibers is first dyed in the manner described above, the cellulosic component remaining sub.- stantially undyed. After raising the pH-value, for example, by means of ammonia, there are added, advantageously without the further supply of heat, first sodium sulfate and then a direct-dyeing cotton dyestufi. It is. of

advantage to use a dyestuff which does not dye 'wool at all or only very slightly in the vicinity of 100 C. The

dyeing is then continued until the cellulose fibers have attained the desired tint, for example, for about /2 hour, and then the, dyeing is finished in the usual manner. In order to improve the properties of wet fastness' of the dyed cellulosefibers it may be of advantage to subject them to an after-treatment in known manner with. an agent capable of improving the properties of wet fastness, for example, the condensation product of dicyandiamide and formaldehyde.

The following examples illustrate the invention, the parts being by weight:

Example 1 100-par-ts of knitting wool, 3000 parts of water, 10 parts of crystalline sodium sulfate, 6 parts of acetic acid of 40% strength and 0.5 part of the addition compound from oleylamine and ethylene oxide described below are heated'to C; A solution of 2 parts of the dyestufi of the formula.

SOIH

ness of this dyeing to wetting, more especially insofar as bleeding into cotton is concerned, is subsequent increase of the pH value. Before the addition of hexamethylene- 6 tetramine the pH is about 4.8, and the addition raises it to Instead of the dyestufi of the above formula there may about 7.2. be used the dyestufl? of the formula The addition compound of ethylene oxide is prepared in the following manner:

100 parts of commercial oleylamine are mixed with 1 5 0-01 part of finely disintegrated sodium, the whole is heated to l N l 140 C. When the ethylene oxide is being absorbed rapidly, the reaction temperature is reduced to 120 to (Red) 125 C., and the introduction of ethylene oxide is con- HO S- SO3H Cl tinued until 113 parts thereof have been absorbed. The

Eamon product obtamed m fins manner glves prac' Practically identical dyeings are obtained when, after tically clear solution in water.

the addition of the dyestufi, the bath temperature 1s Instead of the above ethylene oxide adduct the followraised only to 85 C. dyeing being continued at this ing products may be used:

(a) N-alkyl-propylenediamine (whose alkyl radicals i ii g i th f the H 1 correspond to the radical of tallow fatty acid)+8 mols us a 0 W1 l ma 6 I .lsmg o p Va He towards the conclusion of the dyeing operation may be of g i fil gg g mols of ethylene oxide. achieved with triethanolamine or sodium bicarbonate.

(c) Dodecylamine+3 mols of propylene oxide (this Example 3 product can be prepared thus: 24 parts of commercial dodecylamine are heated to 160 in the presence of 0.13 part of finely disintegrated sodium in a current of nitrogen. Gaseous propylene oxide is then introduced until 19.5 parts thereof have been absorbed); (a) O NH: (d) The acid sulfuric acid ester obtained as follows: 25 II I 79 parts of a mixture of fatty amines (0.3 mol) con- SOSH sisting of of hexadecylamine, 25% of octadecylamine and 45% of octadecenylamine are reacted with ethylene oxide in the presence of 0.8 part of sodium until Dyebaths are prepared containing in 2000 parts of water, 6 parts of acetic acid of 40% strength and 1 part each of the dyestutfs of the formulae:

106 parts (2.4 mols) of ethylene oxide have been ab- 30 O (Blue) sorbed. ll 5 C1 The reaction temperature is at first 140 to 150 C. S033 and can be gradually reduced to 120 to 125 C. 30.75 parts (0.05 mol) of the resulting ethylene oxide adduct (5) H2N are mixed in a stirring flask at 60 C. within 15 minutes I with 5.4 parts of urea and then within 30 minutes with ON=N 5.4 parts of sulfamic acid (0.05 mol+10%) and kept I I l I (Red) for 5 to 6 hours under nitrogen on a boiling water bath. H033 H 7 The resulting product (41 parts) is readily soluble in wa- I ter and is of neutral reaction. 803B (I]N@SO3H (Yellow) HzC(l3HC-HNQN= O\ I O1 01 or 0 so H N Example 2 A piece of wool (100 parts) is immersed at 60 C. in O a dyebath containing in 4000 parts of water 5 parts of I H acetic acid of 40% strength, 10 parts of crystalline sog dium sulfate, 0.25 part of the ethylene oxide adduct de- I scribed in the 2nd paragraph of Example 1 and 2 parts S0311 of the dyestufi of the formula (Red) At 60 C. parts of wool tops are immersed in the sioaH 17111 f k dyebath which is raised to the boil within /2 hour, and N N dyeing is carried out at the boil for 1 hour. The heating TNT-N is then discontinued and 2.5 parts of trisodium phosphate I are added. After 15 minutes, the wool is taken out of H038 $0311 01 the dyebath, rinsed and dried. The resulting dyeings have much better fastness to wetting than when the sub- Th 1 6 whole 18 ralsed to the boll wlmm /2 hour and dye sequent addition of trisodium phosphate is omitted. This mg is P l on at the boll for 1 hour The heanpg 1s addition raises the pH value of the dyebath from about then discontinued, and 3 parts of aqueous ammonia of 47 to about 67 25% strength are added. After 15 minutes the wool is 7 Exam le 4 removed from the dyebath, immediately rinsed in water p and dried. A level red dyeing is obtained having a tast- 100 parts of a blended yarn of equal parts of wool ness to wetting which is much better than when no amand regenerated cellulose (staple fibers) are immersed monia is subsequently added. The addition of ammonia at 50 C. in a dyebath containing in 4000 parts of water raises the pH value from about 5.0 to 8.0. 7 5 parts of acetic acid of 50% strength, 0.5 part of the 7 ethylene oxide adduct described in the 2nd paragraph of Example 1 and 1 part of the dyestufi of the formula The whole is raised to the boil within /z hour and dyeing is continued for /2 hour at the boil. The heating is then discontinued, and 3.5 parts of aqueous ammonia of 25% strength, 30 parts of crystalline sodium sulfate and 1.5 parts of the dyestutf of the formula SiO 311 H (I) are, added. The temperature is allowed to drop to about 80 C. within /2 hour. The dyeing is rinsed in cold water and dried. A very level, pure red dyeing is obtained.

To improve the wet fastness properties of its cellulose fibers, the material dyed in this manner can be aftertreated in known manner with a condensation product from 2 mols of formaldehyde and 1 mol of the reaction product from 1 mol of ethylenediamine dihydrochloride with 2 mols of dicyandiarnide.

What is claimed is:

1. A process for finishing a dyeing produced on nitrogenous fibers in an acid bath with a dyestufi' containing at least one mobile halogen atom, which comprises raising the pH value of the bath above 6 when the fibers have absorbed the desired quantity of dyestuff.

2. A process for finishing a dyeing produced .onwool in an acid bath with a dyestuff containing at least one mobile halogen atom, which comprises raising the pH value of the bath above 6 when the fibers have absorbed the desired quantity of dyestuft.

3. A process for finishing a dyeing produced on wool with a dyestutf selected from the group consisting of a dyestufi containing a chloropropionyl radical and a dyestufi containing a chlorotriazine radical in a bath which is acid with acetic acid at the beginning of the dyeing operation, which process comprises raising the pH value of the bath above 6 when the fibers have absorbed the desired quantity of dyestufl.

4. A process for finishing a dyeing with a dyestufi containing a chlorotriazine radical in a bath which is acid with acetic acid at the beginning of the dyeing operation, which process comprises raising the pH value of the bath above 6 by additon of a nitrogenous base when the fibers have absorbed the desired quantity of dyestufi.

5. A process for finishing a dyeing produced on wool with a dyestuff containing a chlorotriazine radical in a bath which is acid with acetic acid at the beginning of the dyeing operation, which process comprises raising 8 the pH value of the bath above 6 by addition vofammonia when the fibers have absorbed the desired quantity of dyestufl.

6. A process for finishing a dyeing produced on wool with a dyestufi containing a chloropropionyl radical in a bath which is acid with acetic acid at the beginning of the dyeing operation, which process comprises raising the pH value of the bath above 6 by addition of ammonia when the fibers have absorbed the desired quantity of dyestufi.

7. A process for finishing a dyeing produced on wool with a dyestufi containing a chlorotriazine radical in a bath which is acid with acetic acid at the beginning of the dyeing operation, which process comprises raising the OH HOsS with a dyestuff containing a chloropropionyl radical in produced on wool 4 a bath which is acid with acetic acid at the beginning of the dyeing operation, which process comprises raising the pH value of the bath above 6 by addition of hexamethylene 'tetramine when the fibers have absorbed the desired quantity of dyestufi.

9. A process for finishing a dyeing produced on the wool part of a mixture of wool and cellulose fibers in an acid bath with a dyestufl containing at least one mobile halogen atom, which process comprises raising the pH-value of the bath above 6 when the wool fibers have absorbed the desired quantity of dyestufr' and then dyeing the cellulose fibers in the same bath with a substantive dyestuff.

10. A process for finishing a dyeing'produced on the wool part of a mixture of wool and cellulose fiber-s with a dyestufi containing at least one mobile chlorine atom in a bath which is acid with acetic acid, which process comprises raising the pH-value of the bath above 6 when the wool fibers have absorbed the desired quantity of dyestufi: and then dyeing the cellulose fibers in the same bath with a substantive dyestuff.

References Cited in the file of this patent UNITED STATES PATENTS Re. 11,647 Schaefier Feb. 1, 1898 654,864 Wilson July 31, 1900 2,719,104 Westerberg Sept. 27, 1955 2,723,262 Guasco Nov. 8,1955 2,773,871 Brassel et al Dec. 11, 1956 2,895,785 Alsberg et a1 July 21, 1959 2,900,218 Gray Aug. 18, 1959 2,903,324 Hirsbrunner Sept. 8, 1959 2,914,531 Staeuble et a1 Nov. 24, 1959 2,940,812 Denyer et a1. June 14, 1960

Claims

1. A PROCESS FOR FINISHING A DYEING PRODUCED ON NITROGENOUS FIBERS IN AN ACID BOTH WITH A DYESTUFF CONTAINING AT LEAST ONE MOBILE HALOGEN ATOM, WHICH COMPRISES RAISING THE PH VALUE OF THE BATH ABOVE 6 WHEN THE FIBERS HAVE ABSORBED THE DESIRED QUANTITY OF DYESTUFF.