EP0243788A2 - Leather-treating agent - Google Patents

Abstract

Leather treatment compositions contain a mixture of a) 2-98% by weight of an adduct with a molecular weight of 500-50,000 of an alkylene oxide to an aliphatic or aromatic compound containing one or more hydroxyl groups and b) 98-2% by weight of a carboxyl group or its salts containing reaction product with a molecular weight of 170-20,000 from an aliphatic, cycloaliphatic or aromatic compound containing at least two carboxyl groups or their anhydrides and an aliphatic or cvcloaliphatic compound containing at least two hydroxyl and / or primary or secondary amino groups and optionally ether or tertiary amino groups.

Description

• a) 2-98 Gew.-% eines Adduktes mit einem Molgewicht von 500-50.000
  eines Alkylenoxides an eine oder mehrere Hydroxygruppen enthaltende aliphatische oder aromatische Verbindung und
• b) 98-2 Gew.-X eines Carboxylgruppen oder deren Salze enthaltenden Reaktionsproduktes mit einem Molgewicht von 170-20.000 aus
  einer mindestens zwei Carboxylgruppen oder deren Anhydride enthaltenden aliphatischen, cycloaliphatischen oder aromatischen Verbindung
  und
  einer mindestens zwei Hydroxy- und/oder primäre oder sekundäre Aminogruppen und gegebenenfalls Ether- oder tertiäre Aminogruppen enthaltenden aliphatischen oder cycloaliphatischen Verbindung

enthalten, ihre Verwendung sowie Leder, die durch Behandlung mit diesen Mitteln erhalten wurden.The invention relates to leather treatment agents which are a mixture of

• a) 2-98% by weight of an adduct with a molecular weight of 500-50,000
  an alkylene oxide to one or more hydroxyl-containing aliphatic or aromatic compound and
• b) 98-2% by weight of a reaction product containing carboxyl groups or their salts with a molecular weight of 170-20,000
  an aliphatic, cycloaliphatic or aromatic compound containing at least two carboxyl groups or their anhydrides
  and
  an aliphatic or cycloaliphatic compound containing at least two hydroxyl and / or primary or secondary amino groups and optionally ether or tertiary amino groups

included, their use and leather obtained by treatment with these agents.

The leather treatment compositions according to the invention preferably contain components a) and b) in a weight ratio of 95: 5 to 5:95. They are used as a solution, emulsion or dispersion, preferably as an aqueous solution. The pH of the aqueous solutions is between 3 and 9, preferably between 5 and 8.

The total concentration of a) and b) in the leather treatment compositions is, for example, 15-60% by weight, preferably 30-60% by weight.

Components a) are free from amino groups and preferably have a molecular weight of 500-10,000.

The components b) in particular have a molecular weight of 300-10,000.

• a) ein Addukt von Ethylenoxid und/oder Propylenoxid an eine Verbindung der Formel
  
  
  mit R = H, geradkettig oder verzweigtes, gegebenenfalls durch 1-5 OH-Gruppen substituiertes C₁-C₅-Alkyl,
  R₁ = ^H, C₁-C₁₂-Alkyl oder
  
  und als Komponente
• b) ein Reaktionsprodukt einer Säure der Formel
  
  
  mit X = C₁-C₈-Alkylen, -CH=CH-, Cyclohexylen oder gegebenenfalls durch COOH oder Cl substituiertes Phenylen,
  oder ihrer Anhydride und einer Verbindung der Formel
  
  
  oder
  
  • mit Y = geradkettiges oder verzweigtes, gegebenenfalls durch 1-4 OH-Gruppen substituiertes C₂-C₈-Alkylen oder
    
  • Y_{l =} C₂-C₆-Alkylen, gegebenenfalls durch Methyl substituiertes Cyclohexylen,
  • Y₂ = Ethylen, 1,2- oder 1,3-Propylen,
  • R₂, R₃ ⁼ H, CH₃,
  • R₄ = H, -Y₂-OH,
  • m = 3-13, insbesondere einen Mittelwert von 8,
  • n = 2, 3 oder 4.

A preferred mixture contains as a component

• a) an adduct of ethylene oxide and / or propylene oxide with a compound of the formula
  
  
  with R = H, straight-chain or branched, C ₁ -C ₅ alkyl optionally substituted by 1-5 OH groups,
  R ₁ = ^H , C ₁ -C ₁₂ alkyl or
  
  and as a component
• b) a reaction product of an acid of the formula
  
  
  with X = C ₁ -C ₈ alkylene, -CH = CH-, cyclohexylene or phenylene optionally substituted by COOH or Cl,
  or their anhydrides and a compound of the formula
  
  
  or
  
  • with Y = straight-chain or branched, optionally substituted by 1-4 OH groups C ₂ -C ₈ alkylene or
    
  • Y _{l =} C ₂ -C ₆ alkylene, optionally substituted by cyclohexylene,
  • Y ₂ = ethylene, 1,2- or 1,3-propylene,
  • R ₂ , R ₃ ⁼ H, CH ₃ ,
  • R ₄ = H, -Y ₂ -OH,
  • m = 3-13, in particular an average of 8,
  • n = 2, 3 or 4.

• a) einen Alkohol der Formel (I) und als Komponente
• b) ein Reaktionsprodukt aus Maleinsäure oder Phthalsäure oder deren Anhydriden und einem Alkohol der Formel (V).

A particularly preferred mixture contains as a component

• a) an alcohol of formula (I) and as a component
• b) a reaction product of maleic acid or phthalic acid or their anhydrides and an alcohol of the formula (V).

Components a) are produced by adding ethylene and / or propylene oxide to suitable starters. Examples of such hydroxy-functional starting components that can be used are: water; Monoalcohols such as methanol, ethanol, butanol; Diols such as ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,4- and 3,6-dianhydrosorbitol, 4,4'-dihydroxydiphenylpropane; Triols such as glycerin, trimethylolethane, trimethylolpropane; higher polyols such as pentaerythritol, sorbitol, mannitol, formitol, formose, sucrose; Phenol and alkylphenols such as nonylphenol.

Preferred compounds a) are those which are more than 1 g / l water-soluble at 20 ° C.

Components b) are obtained by reacting polyvalent carboxylic acids with polyhydric alcohols, amines and amino alcohols to give oligoester amide carboxylic acids. The carboxylic acids can be used in the form of their anhydrides.

Examples of carboxylic acids are: succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid, phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, isophthalic acid, terephthalic acid, tetrachlorophthalic acid, glutaric acid, maleic acid, fumaric acid.

Examples of polyhydric alcohols are: ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 2,3-butanediol, 1,6-hexanediol, 1,8-ethanediol, neopentylglycol, 1, 4-bis-chydroxymethyl] cyclohexane, 2-melhyl-1,3-propanediol, glycerin, trimethylolpropane, 1,2,6-hexanetriol, 1,2,4-butanetriol, trimethylolethane, pentaerythritol, quinite, mannitol, sorbitol, formitol , Methylglycoside, furthermore in particular oligoethylene glycols and oligopropylene glycols.

Examples of polyvalent amines are: ethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, 1,6-hexamethylenediamine, l-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, 1,4-diaminocyclohexane, Diethylenetriamine, triethylenetetramine, dipropylenetriamine, tripropylenetetramine.

Examples of amino alcohols are: ethanolamine, diethanolamine, N-methylethanolamine, N-methyldiethanolamine, isopropanolamine, diisopropanolamine, N-methylisopropanolamine, N-methyldiisopropanolamine,

When dyeing leather there is often the problem that the dye does not penetrate deep enough into the interior of the leather within the time available. One remedy can be that the dyeing is carried out in the presence of aqueous ammonia at pH values up to 9. There are limits to leather dyeing with ammonia as a penetration aid. ammonia escapes very easily at the usual temperatures of over 40 ° C in dyeing, can cause difficulties during later acidification and can lead to the presence of fat or retanning agents that are present in the leather.

On the other hand, the literature (G. Otto, "The dyeing of the leather", Darmstadt 1962) describes cationic aids. These are either long-chain quaternary ammonium salts or condensates of fatty acids with triethanolamine. Ethylene oxide adducts with fatty acid amides, fatty acids or fatty acid alcohols are also used as leveling aids in dyeing (G.Otto, p. 94).

DE-AS 2 856 628 describes ethylene oxide adducts with alkylamines with 8-20 C atoms as leveling agents and penetration aids for dyes.

DE-AS 2 539 671 also shows that C _4-22 -alkylamines with hydroxyethyl end groups equalize colorations. An alkylamine with preferably more than 12 carbon atoms in the alkyl group and with hydroxyethyl groups is described as dyeing aid in GB-PS 705 335.

Nonionic addition products of ethylene oxide together with ethoxylated C _10-22 fatty amines are described as surface-active dyeing aids for nitrogen-containing substrates such as leather in US Pat. No. 3,334,960.

All of these products are characterized by an often considerable surface-active effect, which on the one hand ensures the improved color yield by reducing the agglomeration effect of the dyes, but on the other hand is responsible for the formation of unwanted foam during the dyeing, which causes stains on the leather surface when it dries . The presence of the cationic groups and the simultaneous surface activity stabilize the dyes in the aqueous liquor. As a result, the dyes are less effectively removed from the dyeing liquor despite strong acidification.

Surprisingly, it has now been found that the mixtures according to the invention do not have these disadvantages. They result in a deep penetration of the dye into the leather and at the same time a high color strength on the surface and excellent exhaustion of the dyeing liquor.

The process for leather treatment with the new mixtures is carried out according to known methods in tanning drums or tanning mixers. The temperatures are generally 10-90 ° C, preferably 30-60 ° C. The aqueous treatment liquors contain a total of 0.01-20% by weight, preferably 0.2-2% by weight (based on the shaved weight) of the agents according to the invention.

The treatment can be carried out before or at the same time as the coloring and also together with the oiling.

The products according to the invention are preferably used together with the dye in solution.

Suitable dyes are the dyes customary for leather dyeing, which are described, for example, in the Color Index, Vol. 2, 3rd Edition.

The amount of the dye applied to the leather and the amount of dye in the remaining liquor are determined optically in the following examples according to the test described by H. Traubel and A. Goffin in "Leather and Skin Market, Sept. 1985" (hereinafter referred to as "Test A" designated) determined.

1. Production of components a)

Alkylene oxide adducts are prepared in a known manner by adding oxiranes to starter alcoholates and then neutralizing, filtering salts and optionally adding oxidation inhibitors.

Product 1.1.

50 parts of a polyether alcohol based on butanol and ethylene oxide / propylene oxide in a molar ratio of 1: 1, which predominantly has hydroxyethyl end groups, with an average molecular weight of 2240, are dissolved in 50 parts of water with stirring.

Product 1.2.

50 parts of a polyether alcohol based on butanol and ethylene oxide / propylene oxide in a molar ratio of 1: 1, which predominantly has hydroxyethyl end groups, with an average molecular weight of 1870, are dissolved in 50 parts of water with stirring.

Product 1.3.

₅₀ parts of a polyether alcohol based on butanol and ethylene oxide / propylene oxide in a molar ratio of 1: 1, which has predominantly hydroxyethyl end groups, with an average molecular weight 1400, are dissolved in 50 parts of water with stirring.

Product 1.4.

50 parts of a polyether triol based on glycerol and ethylene oxide / propylene oxide in a molar ratio of 1: 1, which predominantly has hydroxyethyl end groups, with an average molecular weight of 4670, are dissolved in 50 parts of water with stirring.

Product 1.5.

50 parts of a polyether polyol based on sorbitol and ethylene oxide / propylene oxide in a molar ratio of 9: 1, which has predominantly hydroxyethyl end groups, with an average molecular weight of 4800, are dissolved in 50 parts of water with stirring.

2. Production of components b) Product 2.1.

576 parts of trimellitic anhydride are melted at 180 ° C. 268 parts of dipropylene glycol are added dropwise over the course of 2 hours. Then 54 parts of water are distilled off in a water jet vacuum until the acid number of the product is 288 mg KOH / g. After cooling to 100 ° C., the product is dissolved in a mixture of 618 parts of water and 260 parts of 25% ammonia.

Product 2.2.

392 parts of maleic anhydride are melted at 160 ° C. 740 parts of an oligoethylene glycol with a number average molecular weight of 370 are added dropwise over the course of 2 hours. The mixture is stirred for a further 2 hours until the acid number of the mixture is 203. After cooling to 100 ° C., the product is dissolved in a mixture of 996 parts of water and 272 parts of 25% ammonia to give a solution with a solids content of 50 K.

Product 2.3.

592 parts of phthalic anhydride are melted at 140 ° C. 740 parts of the oligoethylene glycol are added dropwise over the course of 2 hours, as in Example 2.2. The mixture is stirred for a further 2 hours until the acid number of the mixture is 171. After cooling to 100 ° C., the product is dissolved in a mixture of 1196 parts of water and 272 parts of 25% ammonia to give a solution with a solids content of 50%.

Product 2.4.

Analogous to 2.1. 924 parts of hexahydrophthalic anhydride and 438 parts of 2,2,4-trimethylpentanediol-1,3 are reacted at 180 ° _C. up to an acid number of 247 mg KOH / g and dissolved in a mixture of 768 parts of water and 269.5 parts of 25% ammonia .

Product 2.5.

Analogous to 2.4. 800 parts of succinic anhydride and 417 parts of neopentyl glycol are reacted at 120 ° C. up to an acid number of 373 and dissolved in a mixture of 941 parts of water and 550 parts of 25% ammonia.

Product 2.6.

500 parts of glutaric anhydride are initially introduced at 140 ° C. and 372.5 parts of 1-amino-3-aminomethyl-3,5,5-trimethylcylohexane are added dropwise with stirring over the course of 2 hours. The highly viscous product is stirred for 3 hours at 140 ° C until an acid number of 282 is reached. After cooling, a solution with a solids content of 50% is adjusted by adding a mixture of 375 parts of water and 153.6 parts of ammonia.

3. Preparation of the mixtures according to the invention

They are obtained by mixing components a) and b). The compositions 3.1.-3.9 listed in Tab. 1 were produced and tested in detail.

4. Application examples

Chrome-tanned leather (4.0 X Cr ₂ O ₃ based on 14% water) is divided and processed in various ways (percentages relate to the fold weight).

Method A

The leather is washed, neutralized, retanned and dyed according to the following formula:

For dyeing, the liquor is drained off after retanning and 300% water at 50 ° C. and 0.5% of the mixtures 3.1.-3.9 according to the invention are added. After 15 min, 1.5 X Direct Brown 80 (CI 20210) and 3% fat liquor mixture (1) added. After a running time of 40 minutes, the dye is fixed by treatment with 1% 85% formic acid (pH 4-4.5) for 20 minutes.

• 60 Tln. natürlicher und synthetischer Fettsäuren,
• 30 Tln. unverzweigter chlorierter Kohlenwasserstoffe und
• 10 Tln. synthetischen Klauenöls.

(1) = mixture of

• 60 parts of natural and synthetic fatty acids,
• 30 parts of unbranched chlorinated hydrocarbons and
• 10 parts of synthetic foot oil.

The leather is finished as usual. It has a satisfactory surface color strength and good depth of penetration of the dye.

Method B

Washing, neutralizing and retanning are carried out as in method A. The dyeing is carried out as follows.

In the liquor (300%, 50 ° C) 1.8% of the mixtures 3.1.-3.9. and 1.5% of the dye Direct Brown 80 (= C.I. 20210) were given in immediate succession in any order. The running time is 40 min. Greasing and acidification are the same as for method A.

Leather with a high to very high color strength and a good depth of penetration of the dye are also obtained.

Method C

After washing and neutralization analogous to method A, the leather is first tanned with 0.8% of the mixture according to the invention 3.3 without retanning. or 3.6, 15 min treated (300% water, 50 ° C). The coloring is then carried out with 1 X C.I. Acid Black 173 (40 min). Greasing, dye fixation and completion are the same as for method A (Table 2).

Instead of C.I. Acid Black 173 can also C.I. Acid Red 279 and C.I. Acid Brown 429 can be used.

Method D

The leather is treated as in method C, but a retanning as in method A is carried out between neutralization and dyeing.

Method E

Wet blue leather is treated as follows.

Treatment with MitleL 3.3 or 3.6. and the coloring is carried out as described in Method C.

Method F

The leathers are washed, neutralized and dyed as in Method C, using either 1% C.I. Acid Red 279 (Table 3) or 1% C.I. Acid Brown 429 (Table 4) can be used.

As in Method C, a chrome extract is made.

Method G

The leathers are washed, neutralized and retanned as in Method D and dyed as in Method F. The chrome extract is then made.

Method H

Washing, retanning, neutralizing and retanning are carried out analogously to method E and staining analogously to method F. The chrome extract is then again produced.

In methods F-H, the amounts of agent 3.3 e given in Tables 3 and 4 are used.

The determination of the color strength on the leather obtained by the CH methods and the amounts of dye in the remaining liquor are determined according to "Test A" and listed in Tables 2-4. To assess the penetration depth of the dye, the leather is cut open at an angle of 10-20 ° C to the surface and the penetration behavior is assessed visually for comparison.

Claims (8)

1. Agent for the treatment of leather, characterized in that it is a mixture of a) 2-98% by weight of an adduct with a molecular weight of 500-50,000
an alkylene oxide to one or more hydroxyl-containing aliphatic or aromatic compound and b) 98-2% by weight of a reaction product containing carboxyl groups or their salts with a molecular weight of 170-20,000
an aliphatic, cycloaliphatic or aromatic compound containing at least two carboxyl groups or their anhydrides
and
an aliphatic or cycloaliphatic compound containing at least two hydroxyl and / or primary or secondary amino groups and optionally ether and tertiary amino groups
contain. 2. Composition according to claim 1, characterized in that it is a component a) an adduct of ethylene oxide and / or propylene oxide with a compound of the formula

with R = H, straight-chain or branched, C ₁ -C ₅ alkyl optionally substituted by 1-5 OH groups,
R ₁ ⁼ H, C ₁ -C ₁₂ alkyl or

and as a component b) a reaction product of an acid of the formula

with X = C ₁ -C ₈ alkylene, -CH = CH-, cyclohexylene or phenylene optionally substituted by COOH or Cl,
or their anhydrides and a compound of the formula

or

with Y = straight-chain or branched, optionally substituted by 1-4 OH groups C ₂ -C _S alkylene or

Y ₁ = C ₂ -C ₆ alkylene, cyclohexylene optionally substituted by methyl, Y ₂ = ethylene, 1,2- or 1,3-propylene, R ₂ , R ₃ = H, CH ₃ , R ₄ ⁼ H, -Y ₂ -OH, m = 3-13, in particular an average of 8, n = 2, 3 or 4,
contain. 3. Composition according to claim 1, characterized in that as component a) an alcohol of the formula

and as component b) a reaction product from maleic acid or phthalic acid or their anhydrides and from an alcohol of the formula

wherein R, R ₂ , R ₃ and m have the meaning given in claim 2,
contain. 4. Composition according to claim 1, characterized in that they represent solutions, emulsions or dispersions with a total content of a) and b) of 15-60% by weight. 5. Composition according to claim 1, characterized in that they represent aqueous solutions with a total content of a) and b) of 15-60% by weight and a pH of 3-9. 6. A method of treating leather, characterized in that an agent of claim 1 is allowed to act on tanned leather before or simultaneously with a dye. 7. The method according to claim 6, characterized in that the leather is treated at 10-90 ° C with an aqueous liquor containing 0.01-20% by weight of an agent of claim 1. 8. Leather obtained by treatment with an agent of claim 1.