EP0252386A1 - Process for improving the fastness to light of polyamide dyeings - Google Patents

Abstract

1. Process for improving the light fastness of dyeings on polyamide fibre materials by using copper compounds, characterized in that the copper compounds used are the 1:2 complexes of aromatic hydroxycarbonyl compounds of the formula (I) see diagramm : EP0252386,P7,F2 wherein R1 and R2 independently of each other denote H, OH or OW and X1 -X8 independently of one another denote H, W, OH, halogen, CN, NH2 , NVW, SO3 H, COOH, COOW, CONVW or CONH2 and two adjacent radicals X1 -X8 can also together form the remaining members of a fused-on benzene ring, where W represents C1 -C18 alkyl and V represents W or H, subject to the proviso that the 2nd order substituents mentioned above for X1 -X8 appear at most twice in a benzene radical.

Description

The invention relates to a process for improving the light fastness of dyeings on polyamide fiber materials, in particular textile materials for the automotive sector, using copper compounds.

As is known, the light fastness of seat covers, carpets and other lining materials for motor vehicles is subject to the highest demands, which cannot be satisfied with numerous commercially available dyes alone.

In addition to the "normal" light fastness according to DIN 54 003 and 54 004, a high light fastness with strong heat is also required, as has recently been determined by hot exposure according to DIN 75 202 (draft).

To meet this standard, various copper compounds, such as complex compounds of Schiff bases, o-hydroxybenzophenones and oximes (cf. EP-A 51 188 and 113 856), have already been proposed in addition to numerous other light fastness enhancers.

However, these aids have so far not been able to fully meet the high demands of automobile manufacturers, since the effects achieved were not quite sufficient. Some of the auxiliaries also have an undesirable inherent color and / or are relatively expensive because of their complex production method.

Finally, the fact that the effect of the abovementioned classes of substances decreases at higher concentrations is particularly disadvantageous, so that their possible uses are limited.

verwendet, worin

R₁ und R₂ unabhängig voneinander H, OH oder OW und

X₁-X₈ unabhängig voneinander H, W, OH, Halogen, CN, NH₂, NVW, SO₃H, COOH, COOW, CONVW oder CONH₂ bedeuten und zwei benachbarte Reste

X₁-X₈ auch gemeinsam die restlichen Glieder eines ankondensierten Benzolringes bilden können,

wobei

W für C₁-C₁₈-Alkyl und

V für W oder H stehen,

mit der Maßgabe, daß die vorstehend für X₁-X₈ genannten Substituenten 2. Ordnung maximal 2fach in einem Benzol­rest auftreten.It has now surprisingly been found that very lightfast dyeings can be achieved largely without these disadvantages if 1: 2 copper complexes of the formula are used as auxiliaries

used where

R₁ and R₂ independently of one another H, OH or OW and

X₁-X₈ independently of one another are H, W, OH, halogen, CN, NH₂, NVW, SO₃H, COOH, COOW, CONVW or CONH₂ and two adjacent radicals

X₁-X₈ can also together form the remaining members of a condensed benzene ring,

in which

W for C₁-C₁₈ alkyl and

V stands for W or H,

with the proviso that the second order substituents mentioned above for X₁-X₈ occur at most twice in a benzene radical.

Suitable halogen atoms are F, Br and especially Cl. Suitable alkyl radicals are straight-chain or branched and optionally unsaturated.
The acid groups mentioned can also be in salt form.

Preferred compounds of formula I are symmetrical types.

Particularly preferred are those of the formula I in which X₃ and X₆ are C₁-C₁₀ alkyl or chlorine and those of this formula in which X₂ and X₇ are OH, the other X radicals being hydrogen.

Compounds of the formula I with the abovementioned general and preferred meanings in which R 1 and R 2 = OH are very particularly preferred.

• a) Salicylsäure
• b) 5-Methylsalicylsäure (p-Kresotinsäure)
• c) 5-tert.-Butylsalicylsäure
• d) 5-Chlorsalicylsäure
• e) 5-tert.-Octylsalicylsäure
• f) 2,4-Dihydroxybenzoesäure (β-Resourcylsaüre)
• g) 2-Hydroxynaphtalin-1-carbonsäure (2-Hydroxy-1-naphthoesäure)
• h) 4-Hydroxy-1,3-benzoldicarbonsäure (4-Hydroxy-isophthalsäure)
• i) Salicylaldehyd
• j) 5-Chlorsalicylaldehyd
• k) 3-Methoxysalicylaldehyd.

Examples of the compounds to be used according to the invention are 1: 2 complexes of copper with

• a) Salicylic acid
• b) 5-methylsalicylic acid (p-cresotinic acid)
• c) 5-tert-butylsalicylic acid
• d) 5-chlorosalicylic acid
• e) 5-tert-octylsalicylic acid
• f) 2,4-dihydroxybenzoic acid (β-resourcyl acid)
• g) 2-hydroxy-naphthalene-1-carboxylic acid (2-hydroxy-1-naphthoic acid)
• h) 4-hydroxy-1,3-benzenedicarboxylic acid (4-hydroxy-isophthalic acid)
• i) salicylaldehyde
• j) 5-chlorosalicylaldehyde
• k) 3-methoxysalicylaldehyde.

The copper complexes according to the invention can also be obtained from mixtures of aromatic o-hydroxycarboxylic acids. The amount used is 0.01 to 3, preferably 0.05 to 0.2% by weight (based on polyamide).

The Cu complexes according to the invention are prepared in a manner known per se by reacting alkali metal salts of aromatic o-hydroxycarboxylic acids in an aqueous medium with a copper (II) salt, such as CuCl₂, CuSO₄ · 5H₂O, Cu (OAc) ₂ · H₂O or CuCO₃ · Cu (OH) ₂.

1: 2 Cu complexes of salicylic acid are e.g. in Gmelin's Handbook of Inorganic Chemistry 8th edition, Verlag Chemie Weinheim 1961, system no. 60, page 800-804.

The dyeings on polyamide fibers can be produced in a conventional manner with azo metal complex dyes and anthraquinone dyes as well as with acid dyes. The metal complex dyes, in particular the 1: 2 chromium or 1: 2 cobalt complexes of azo compounds, which are described in large numbers in the literature and are commercially available, are preferred. These dyes can also contain 1 to 2 sulfo groups.

The treatment of the polyamide materials with the copper compounds to be used according to the invention can take place before, during or after, preferably during the dyeing.

Unless they are water-soluble, the copper compounds normally produced separately are used in finely divided form, as is obtained by grinding in the presence of customary dispersants.

According to a special embodiment of the method according to the invention, this is carried out, as it were, in a "one-pot", in that the fiber materials are not treated directly with the copper compounds isolated in solid form, but - in principle in any order - are produced in situ from the corresponding starting materials on the fiber.

In this variant, the fibers are first dyed with a dyeing liquor which, in addition to the dye and, if appropriate, customary dyeing auxiliaries, contains the metal-free compounds of the formula I and then aftertreated with a copper (II) salt solution. The compounds of the formula I are preferably used without any co-catalysts. The dyeings obtainable with the copper complexes to be used according to the invention are distinguished by a high resistance to hot light irradiation in accordance with DIN 75 202, and there is no discoloration of the fiber even with a higher dosage of these auxiliaries

From DE-A-2 000 688 salicylic acid derivatives are already known as dyeing aids. However, these connections are used there for a completely different purpose, namely to avoid the so-called catalytic fading effects.

It was also not recognized that the Cu complexes in particular have an outstanding lightfastness-improving effect, and in particular the 1: 2 complexes. Surprisingly, 1: 1 complexes do not reach the state of the art. Other metal salts of aromatic hydroxycarboxylic acids have a much weaker effect.

In the examples below, "parts" mean parts by weight.

example 1

Preparation of disalicylate copper 138 g of salicylic acid are dissolved in 500 ml of water with the addition of 100 g of 40% NaOH. A solution of 125 g of CuSO₄ · 5H₂O in 350 ml of H₂O is then added dropwise at 50 ° C. and the mixture is stirred at 50 ° C. for 1 hour. After filtering off, 160 g of copper complex are obtained as green crystals with a Cu content of 18%.

Example 2

Di-p-tert-butylsalicylate copper are obtained from 2 moles of 5-tert-butylsalicylic acid, 2 moles of NaOH and 1 mole of CuSO₄ · 5H₂O by the method of Example 1 as green crystals with a Cu content of 14%.

Example 3

Disalicylate-copper-5,5ʹ-disulfonic acid Na salt 234 g of 2-hydroxybenzoic acid-5-sulfonic acid and 80 g of NaOH are dissolved in 620 g of water. Then a solution of 125 g of CUSO₄ · 5H₂O in 350 ml of water is added dropwise and the mixture is heated at 50 ° C. for 1 hour. A dark green, about 22% aqueous solution of disalicylate-copper-5,5'-disulfonic acid Na salt is obtained, which can be used in this form to stabilize polyamide dyeings.

Example 4

61 g of salicylaldehyde and 20 g of NaOH are dissolved in 350 ml of water and a solution of 62.5 g of CuSO₄ · 5H₂O in 175 ml of water is added at room temperature. After suction and drying, about 70 g of green crystals with a Cu content of 18.4% are obtained.

Example 5

erthält. Durch Zugabe von Mono- und Dinatriumpsophat wird ein pH-Wert von 8 eingestellt. Dann wird die Flottentemperatur unter Bewegung des Färbegutes langsam auf 98 bis 100°C erhöht und 60 Minuten bei dieser Tempe­ratur belassen.
Anschließend wird die Färbung dem Färbebad entnommen, gespült und getrocknet.100 parts of polyamide 6 fiber material are introduced into 2,000 parts of aqueous dye liquor, the 0.08 part of the copper complex of preparation example 1 and 0.15 part of the dye of the formula

receives. A pH of 8 is set by adding mono- and disodium psophate. Then the liquor temperature is slowly increased to 98 to 100 ° C. while moving the material to be dyed and left at this temperature for 60 minutes.
The dye is then removed from the dye bath, rinsed and dried.

The dyeing is subjected to a hot exposure together with a comparative dyeing prepared without the copper complex mentioned in accordance with the draft DIN 75 202. The dyeing thus produced shows excellent lightfastness.

Example 6

An equally good improvement in the resistance to hot exposure is obtained if the liquor is adjusted to pH 5.5 instead of pH 8, but with monosodium phosphate and acetic acid.

Example 7

enthalten.100 parts of polyamide 6 material are introduced into 2,000 parts of aqueous dye liquor, the 0.15 part of the copper complex described in Example 1 and 0.15 part of the dye of the formula

contain.

The dye liquor is adjusted to pH 5.5 with the aid of a buffer mixture of mono-sodium phosphate and acetic acid. It is treated for one hour at 98 to 100 ° C, rinsed and dried.

The coloring produced in this way shows a clearly better light fastness than one produced without the copper complex mentioned.

Example 8

If the dyeings prepared according to Examples 5 to 7 are subsequently heat-set at 180 ° C. for 30 seconds, the improvement in light fastness is fully retained.

Example 9

If the dyeings prepared according to Examples 5 to 7 are adjusted to pH 8 or pH 5.5 with the appropriate buffer mixtures and treated in an aqueous medium at 98 to 100 ° C. for 30 minutes, the improvement in light fastness is fully retained.

Example 10

In the dyeing produced according to Examples 5 to 7, the color tone is practically not compared to the dyeings produced without the copper complex mentioned influenced, in contrast to the colorings listed in EP-A-51 188, application example 2a and EP-A-113 856, application examples 1a and 2.

If the procedure is as described in Examples 5 to 7, but the copper compound described in Preparation Example 2 is used, a clear improvement in the hot light fastness is obtained both at pH 8 and at pH 5.5.

Example 11 (comparative example )

If the procedure is as described in Examples 5 to 7, but the 1: 1 copper salicylate complex known from the literature is used, only a slight improvement in the fastness to hot light is achieved both at pH 8 and at pH 5.5 of the dyeing liquor.

Example 12

A polyamide 6 dyeing prepared in a known manner from a long liquor with the dye "Acid Yellow 151" (C.I. 14906) is treated as follows after completion and drying:

The dyeing is impregnated on the pad with 0.7 g / l of a 20% strength aqueous dispersion of the copper complex described in Example 1. The wet weight gain is 70%.

After impregnation, it is dried at 120 ° C. and then heat-set at 180 ° C. for 30 seconds.

The dyeing treated in this way, exposed according to draft DIN 75 202, has a significantly better light fastness than the untreated dyeing.

Example 13

If the dyebath according to Examples 5 to 7 or the impregnation bath from Example 12 is used instead of the copper complex from Preparation Example 1, copper sulfate and sodium salicylate in a molar ratio of 1: 1.8 to 1: 3, then an improvement in the lightfastness is achieved .

Example 14 (comparative example )

If dyeing is carried out as described in Examples 5 to 7, but instead of the copper complex from Example 1 the corresponding nickel or zinc complex is used at 0.1% based on the fiber weight, neither at pH 5.5 nor at pH 8 of the dye liquor an improvement in light fastness.

The dyeings behave as if no light stabilizer has been added to the dyeing liquor.

Claims (8)

1. Process for improving the light fastness of polyamide dyeings by using copper compounds, characterized in that the copper compounds are the 1: 2 complexes of aromatic hydroxycarbonyl compounds of the formula (I)

uses what

R₁ and R₂ independently of one another H, OH or OW and

X₁-X₈ independently of one another are H, W, OH, halogen, CN, NH₂, NVW, SO₃H, COOH, COOW, CONVW or CONH₂ and two adjacent radicals

X₁-X₈ can also together form the remaining members of a condensed benzene ring,

in which

W for C₁-C₁₈ alkyl and

V stands for W or H,

with the proviso that the second order substituents mentioned above for X₁-X₈ occur at most twice in a benzene radical. 2. The method according to claim 1, characterized in that one uses 0.01 to 3% (based on the fiber weight) of the copper compound. 3. The method according to claim 1, characterized in that using the 1: 2 copper compounds of salicylic acid, 5-methylsalicylic acid, 5-tert-butylsalicylic acid, 5-chlorosalicylic acid or naphthoic acid. 4. The method according to claim 1, characterized in that one uses the 1: 2 copper compound of salicylaldehyde or 5-chlorosalicylaldehyde. 5. The method according to claim 1, characterized in that one uses the 1: 2 copper compound of salicylic acid. 6. The method according to claim 1, characterized in that the copper compounds are added to the dyebath. 7. The method according to claim 1, characterized in that polyamide dyeings of metal complex dyes are improved. 8. The method according to claim 1, characterized in that improving the coloring of synthetic polyamides.