Processes for the mass dyeing of synthetic polyamides

Salts of ionic dyes with compounds which contain at least one ammonium, cycloammonium or immonium group and at least one aliphatic, cycloaliphatic or carbonyl radical-substituted aromatic group or containing a piperazine or piperidine group or a heteroaromatic group selected from those of the triazine, pyrimidine, quinazoline, quinoxaline, phthalazine or phthalimidine series or which contain at least two carboxylic acid groups, at least one amino groups and at least one carboxylic acid group or at least one sulfonic acid group and one aliphatic, cycloaliphatic, monocyclic aromatic or heteroaromatic group are useful for dyeing synthetic materials, particularly synthetic polyamides in the mass. The obtained dyeings have exceptionally good wet fastness.

The present invention relates to dyestuffs having improved wet-fastness for 
use with synthetic materials such as synthetic polyamides. 
It has been shown that fiber material consisting of synthetic polyamides 
which has been mass-dyed with anionic dyestuffs has poor wet-fastness, 
especially poor washing fastness. The dyestuffs bleed into the washing 
liquor disproportionately, which has led to strong protests from 
consumers. 
A class of dyestuffs has now been found which are eminently suitable for 
the mass-dyeing of synthetic polyamides, especially those which are 
processed into fiber material. The obtained dyeings have considerably 
improved wet-fastness. 
Accordingly, the present invention provides salts of the formula 
EQU F.(A).sub.n (I), 
and mixtures of such salts, 
wherein 
F is the radical of an anionic or cationic dyestuff and 
A, when F is the radical of an anionic dyestuff, is a group containing at 
least one ammonium, cycloammonium or immonium group and at least one 
aliphatic, cycloaliphatic or carbonyl-substituted aromatic group, or A is 
a group containing a piperazine or piperidine group or a heteroaromatic 
group selected from those of the triazine, pyrimidine, quinazoline, 
quinoxaline, phthalazine, and phthalimidine series, with the proviso that 
when the group A contains at least one aliphatic or cycloaliphatic group 
but no aromatic or heteroaromatic group, it also contains at least one 
cycloammonium group; or 
A, when F is the radical of a cationic dyestuff, is a group containing at 
least two carboxylic acid groups (e.g., a C.sub.2-14 aliphatic 
dicarboxylic acid) or at least one amino group and at least one carboxylic 
acid group (e.g., an amino-C.sub.2-12 alkyl-carboxylic acid) or at least 
one sulfonic acid group together with one aliphatic, cycloaliphatic, 
monocyclic aromatic or heteroaromatic group; and 
n is 1, 2, 3 or 4. 
The compounds of formula I are novel. 
In this specification, the term "carbonyl" (of the carbonyl-substituted 
aromatic groups) means a -CO- radical, the term "ammonium" means an 
##STR1## 
no two valences of which are linked together to form a heterocyclic ring 
together with the nitrogen atom, the term "cycloammonium" means an 
##STR2## 
two or more valences of which are linkied together to form a heterocyclic 
ring together with the nitrogen atom, and the term "cationic dyes" 
embraces dyes having a free amino group that is protonated upon reaction 
with A. 
Suitably, radicals F are of anionic dyestuffs, such as those of the azo, 
anthraquinone, phthalocyanine and dioxazine series, preferably of 
metallized azo dyes free from sulfonic acid groups, particularly the 
chromium complex dyes. Preferred radicals F of cationic dyestuffs are, for 
example, those of the azo and triphenylmethane dyes. 
Preferably A, when F is the radical of an anionic dyestuff, is a group 
containing one or two ammonium groups and a C.sub.1-12 alkyl, cyclohexyl, 
piperazine, triazine, pyrimidine, quinazoline, quinoxaline, phthalazine, 
phthalimide, phenyl or fused benzene group, most preferably containing a 
phenyl, fused benzene or 1,3,5-triazine group. 
When F is the radical of an anionic dye, A preferably contains a 
cycloammonium group, most preferably a 2,2,6,6-tetramethylpiperidinium 
group or a piperazinium group, the piperazinium group linked by the 
cycloammonium nitrogen atom. 
Preferably, n is 1 or 2; most preferably, n is 1. 
Preferably, the radical A contains a group selected from: 
(a) a phenyl or fused benzene group which is substituted by one to four 
groups of the formula 
##STR3## 
wherein when p Is 0, c is a group R.sub.1a, and when p is 1, c is a group 
R.sub.1b ; 
wherein R.sub.2 is -O- or -NR.sub.3 -, and each R.sub.3, R.sub.4, R.sub.5 
and R.sub.6 is independently hydrogen or C.sub.1-2 alkyl, with the proviso 
that when c is a group R.sub.1a there is a cationic group elsewhere in the 
molecule: 
(b) a triazine group which is substituted at the 2- and 4-positions by a 
group of formula R.sub.1a and a group of formula R.sub.1b and at the 
6-position by chlorine or, where appropriate, a group of formula R.sub.1a 
; and 
(c) a triazine group which is substituted at each of the 2- and 4-positions 
independently by a group of the formula 
EQU --NH--(CH.sub.2).sub.2-4 -N.sym.H(R.sub.7).sub.2, 
wherein each R.sub.7 is independently C.sub.1-4 alkyl, preferably C.sub.1-2 
alkyl, the two R.sub.7 groups more preferably being identical, and at the 
6-position by chlorine. 
Most preferably, when A contains a benzene group, the benzene group is 
substituted by one, two or three substituents of formula R.sub.1a (i.e. 
the free amine form) and one or two substituents of formula R.sub.1b (i.e. 
the basic ammonium form). 
Preferably A, when the radical F is cationic, contains an aromatic or 
heteroaromatic bridging group linking from one to four carboxylic acid or 
sulfonic acid group-containing side chains or it is a C.sub.2-14 
-dicarboxylic acid or an amino-C.sub.2-12 carboxylic acid. 
Preferably an acid side chain has the structure -X-Y-Z, wherein X is 
--NH--or --CONH--, Y is C.sub.1-14 alkylene or phenylene, and Z is 
--CO.sub.2 H or --SO.sub.3 H. 
In this specification, any group which is capable of being linear or 
branched may be linear or branched, e.g., alkyl groups and alkylene 
radicals may be linear or branched. 
The salts of the present invention may be used for mass-dyeing of plastics 
such as, for example, synthetic polyamides of all classes, conveniently 
synthetic polyamides which are processed into fiber material. 
The dyeings obtained with these salts are very colorfast and brilliant and 
have considerably better wet fastness, especially washing fastness, than 
the corresponding dyestuff F not bound to a group A. 
Suitable dyestuffs which form radicals F of the present invention and react 
to give salts of the invention are for example, dyestuffs given in Colour 
Index, Third Edition, 1971 and supplements (see also Colour Index 
International 1987) under "Acid Dyes" and "Direct Dyes" "Solvent Dyes" 
containing acid or basic groups and those given as "Basic Dyes" as well as 
more recently developed dyes with similar properties. These are generally 
of better solubility in the commonly used solvents than the common solvent 
dyes. In ethanol, for example, most will reach solubilities of up to 400 
g/liter. 
Preferably A is derived from one of the following Components A (shown in 
the free amino or cyclic amino form): 
1. 1,3,5-tri-(2',2',6', 6'-tetramethylpiperidyl-4')-trimesic acid triamide 
2. 2,4-bis-(2',2',6',6'-tetramethylpiperidyl-4'-amino)-6-chlorotriazine 
3. 2,4,6-tri-(2',2',6',6'-tetramethylpiperidyl-4'-amino)triazine 
4. 
bis-(2',2',6',6'-tetramethylpiperidyl-4'-aminocarbonyl-paraphenylene)-tere 
phthalic acid diamide 
5. bis-(2',2',6',6'-tetramethylpiperidyl-4')-terephthalic acid diamide 
6. 2,4-bis-(2',2',6',6'-tetramethylpiperidyl-4'-amino)quinazoline 
7. 2,3-bis-(2',2',6',6'-tetramethylpiperidyl-4'-amino)quinazoline 
8. 1,4-bis-(2',2',6',6'-tetramethylpiperidyl-4'-amino)phthalazine 
9. 2-chloro-4,6-bis-(2',2',6',6'-tetramethylpiperidyl-4'-amino)pyrimidine 
10. 
2,5-dichloro-4,6-bis-(2',2',6',6'-tetramethylpiperidyl-4'-amino)pyrimidine 
11. 
2-fluoro-5-chloro-4,6-bis-(2',2',6',6'-tetramethylpiperidyl-4'amino)pyrimi 
dine 
12. 2,4,6-tri-(2',2',6',6'-tetramethylpiperidyl-4'-amino)pyrimidine 
13. 
2,4,6-tri-(2',2',6',6'-tetramethylpiperidyl-4'-amino)-5-chloropyrimidine 
##STR4## 
33. (CH.sub.3).sub.2 C(CONH-R.sub.1).sub.2 34. H.sub.2 N-(CH.sub.2).sub.8 
-CONH-R.sub.1 
wherein each R.sub.1 in Formulae 14-34 is 
##STR5## 
2,4,6-tri-(2',2',6',6'-tetramethylpiperidyl-4) 
Preferred compounds A, given in the free acid form for salt formation with 
basic dyes are, for example: 
35. H.sub.2 N-(CH.sub.2).sub.8 -COOH 
##STR6## 
37. 4-(benzoylamino)benzoic acid 
##STR7## 
47. 2,4-bis-(4'-carboxyphenylamino)-6-chlorotriazine 
##STR8## 
49. 1,4-bis-(4'-carboxyphenylaminocarbonyl)benzene 50. 
1,3-bis-(4'-carboxyphenylaminocarbonyl)benzene 
51. 1,2-bis-(4'-carboxyphenylaminocarbonyl)benzene 
52. 4-phenylbutanoic acid 
53. 1,4-butanedioic acid 
54. 1,2-ethanedioic acid 
Examples of anionic dyestuffs are: 
C.I. Acid Blue 25, 40, 72, 106, 126, 129, 227, 230, 278, 280 and 296 
C.I. Acid Yellow 59, 112, 114, 127 and 129 
C.I. Acid Red 261 and 404 
C.I. Acid Green 40 
C.I. Acid Orange 82 
C.I. Acid Violet 66 
C.I. Acid Brown 28, 30 and 289 
C.I. Acid Black 58 and 115 
C.I. Solvent Yellow 83 
C.I. Solvent Red 90:1, 91 and 92 
C.I. Solvent Black 45. 
Examples of cationic dyestuffs are: 
C.I. Basic Yellow 13 and 49 
C.I. Basic Orange 40 
C.I. Basic Green 4 
C.I. Basic Red 14, 22, 46 and 49 
C.I. Basic Violet 16 
C.I. Basic Blue 41, 54 and 78. 
Production of the partly new components A, the amino or imino compounds, is 
effected in accordance with processes which are well known to those 
skilled in the art [amide formation from the acid chloride (e.g. trimesic 
acid trichloride, Example 1) and an amine (e.g. 
2,2,6,6-tetramethyl-4-aminopiperidine), condensation of amines with 
triazinyl halide, etc.]. 
Production of the dyestuff salts of formula I similarly takes place in any 
way which is known to those skilled in the art. The acidic dyestuffs may 
be generally reacted, as they occur following production (e.g. as sodium 
salts), in the presence of adequate quantities of a mineral acid (e.g. 
HCl) with the basic components A, whilst forming a salt. The cationic 
dyestuffs are preferably reacted in a slightly alkaline medium with the 
components A containing the acidic groups. Mass-dyeing takes place in 
accordance with known methods. 
By synthetic polyamides is understood all known artificial materials of 
this kind, especially the polycondensates or polymerisates of dicarboxylic 
acids and diamines, e.g. of adipic acid and hexamethylenediamine and of 
lactams, e.g. w-aminoundecanoic acid. The polyamide melts which are mixed 
with the dyestuffs of formula I are shaped in the usual way, e.g. in melt 
spinning machines, injection moulding machines, extruding machines or 
sheet blowers.

EXAMPLE 1 
Preparation of component A (formula 1 of the above series of formulae) 
42.0 g of trimesic acid are heated for 5 hours to 80.degree. C. with 144.0 
ml of thionyl chloride in the presence of a catalytic quantity (3 ml) of 
dimethylformamide, then the excess thionyl chloride is distilled off, and 
the trimesic acid trichloride thus formed is dissolved in 500 ml of 
dioxane. A total of 187.2 g of 2,2,6,6-tetramethyl-4-aminopiperidine is 
added in drops whilst stirring, whereby dioxane (2000 ml altogether 
together) is constantly added so as to allow the reaction mixture, whose 
temperature should never exceed 30.degree. C., to remain stirrable. The 
reaction mixture is subsequently boiled for 48 hours with reflux cooling, 
and the residue is filtered, washed with acetone dissolved in ca. 1000 ml 
of water, precipitated again with soda solution (at pH 10 to 11), 
filtered, washed with water and vacuum dried yield 89.2 g=72% of a white 
powder with a melting point of &gt;320.degree. C.). 
Preparation of a dyestuff salt according to the invention: 
A solution of 20.8 g of the red dyestuff of formula a.sub.1 
##STR9## 
in 200 ml of water, 0.75 ml of HCl 3% and 0.4 g of salicylic acid is 
heated for 1 hour to 40.degree. C., slowly mixed whilst stirring with a 
solution of 15.6 g of the triamide obtained as described above in 30 ml of 
water and 2.6 ml of HCl 30% and stirred for a further hour at 40.degree. 
C., and the deposit is filtered off, washed with water and vacuum dried. 
21 g of a dark red product of formula a.sub.2 
##STR10## 
is obtained. Its melting point is above 320.degree. C. 
Application Example 1 (All parts are parts by weight.) 
100 parts of poly-.epsilon.-caprolactam in powder form are mixed in a drum 
mixer with 1 part of the dyestuff according to the above example. The 
powder disperses very evenly within a short time. After ca. 10 minutes, 
the mixture is dried for 16 hours at 120.degree. C., placed in a melt 
spinning machine, and after a dwelling time of 8 minutes at 
275.degree.-280.degree. C. under a nitrogen atmosphere, it is spun into 
fibres. The red-dyed fibres have exceptional light, washing and rubbing 
fastness. 
Instead of the dyestuff of formula a.sub.1, the dyestuffs 
C.I. Acid Yellow 59 (Ex. 2) 
C.I. Acid Violet 66 (Ex. 3) 
C.I. Acid Red 404 (Ex. 4) 
were also reacted as described above to form dyestuffs according to the 
invention (with salt formation), dyed on poly-.epsilon.-capro-lactam and 
spun into fibres. 
The dyestuff given in Example 1 was also reacted with the above-mentioned 
components A 2. to 34., by analogy with Example 1, to form salts and spun 
into fibres as indicated in the application example. 
EXAMPLE 5 
261.5 g of 2,4-bis-(carboxymethylamino)-6-chlorotriazine was distributed in 
300 ml distilled water and added, whilst stirring, to a solution of 40 g 
NaOH in 300 ml distilled water. The mixture was stirred at room 
temperature for ca. 1 hour followed by the addition of 697.4 g of the pure 
dyestuff C.I. Basic Red 46. The mixture was stirred for a further hour at 
room temperature, and the red dyestuff which formed in the mixture was 
filtered off and dried. The solubility of this dyestuff in ethanol is 
greater than 250 g/liter. 
Application Example 2 
(All parts are given as parts by weight and percentages as percentages by 
weight.) 
To 95 parts of a Nitrocellulose lacquer comprising: 
18.8% Nitrocellulose A15 moistened with 35% isopropanol (in the form of 
white flakes) 
6.3% acrylic acid butylester polymer, softening resir (Acronal 4F, BASF) 
3.3% diphenyloctylphosphate, softener (Santicizer 141, Monsanto) 
10.0% methoxypropanol (Dowanol PM, Dow Chemicals) 
10.0% ethoxypropanol 
41.6% ethanol 
10.0% ethyl acetate 
was added, with stirring, 5 parts of the dyestuff salt of Example 2, and 
this was left in a rolling frame overnight after which dissolution was 
complete. 
Aluminum foil a) unlacquered and b) lacquered with colorless Nitrocellulose 
lacquer was coated with a 25 .mu.m drawn wet-film of the lacquer-mixture 
and left to dry for 5 hours at 130.degree. C. The consistency of the 
dyestuff salts assessed by the transparency of the dried film. and the 
adhesive strength on the unlacquered and the previously lacquered aluminum 
foil using the Scotch-tape-test were determined. Both properties were 
judged perfect.