EP0476257A1 - Aminodicarboxylic acids and their derivatives as stabilizers for the oxygen bleaching of fabric during washing - Google Patents

Abstract

The use of amino acids prepared from natural material or biotechnologically as bleach stabilisers. Conventional bleach stabilisers have poor biodegradability and are usually very elaborate to prepare. Amino acids are now proposed as bleach stabilisers, which have been prepared naturally or biotechnologically. It is possible to use, inter alia, L-glutamic acid or L-aspartic acid and/or their succinic acid and/or maleic acid amides and/or monocarboxymethylates both in the acid form and in the form of their alkali metal salts. A process for commercial laundering of textiles is likewise described.

Description

The invention relates to chemical compounds or mixtures of substances with the property of increasing the bleaching effect of bleaching agents containing bleaching active oxygen of oxidation level -1 in textile washing / bleaching in the presence of traces of heavy metal ions.

In Western Europe, sodium perborate or hydrogen peroxide is used almost exclusively as a bleaching agent for textile bleaching during washing, which, in addition to the surfactants and other active ingredients, is said to contribute to dirt detachment and fabric lightening during the washing process. Typical stains that can hardly be removed without bleach include e.g. B. red and blue anthocyanin dyes of fruit, turmeric dyes from curry and mustard, brown tannins from tea, humic acids from coffee, tea, cocoa and carotenoid dyes from carrots and tomatoes.

The principle of action of the bleaching agents comprises the chemical saturation of delocalized double bond systems of the colored soils by hydroxylation and their subsequent oxidative fragmentation to form water-soluble products.

A high effectiveness of the bleaching requires a selective selective oxidative attack on the double bonds of the colored soiling. This protects the textile fibers in large excess from oxidative damage. The chemical reaction mechanisms of effective bleaching and fiber-damaging side reactions differ considerably. This opens up possibilities to intervene in a controlling manner in the way the bleaches work. So-called bleaching systems can result from the processing of such problems.

Sodium perborate or hydrogen peroxide form peroxide anions (I) in the alkaline washing liquor, which have a bleaching effect at higher washing temperatures above about 70 ° C.

Nowadays, lower washing temperatures of 30 ° C - 60 ° C are common. The perborate must therefore be "activated". Detergents are added, for example, to tetraacetylethylenediamine (TAED) or sodium p-isononanoylbenzenesulfonate (ISO-NOBS), which are mixed with the hydrogen peroxide formed from sodium perborate to form peracids, namely peroxyacetic acid (11) from TAED or peroxiisononanoic acid (111) from iso-NOBS react. The peracids have a bleaching effect even at low washing temperatures.

The peroxide anions attack double bonds of colored contaminants nucleophilically, while they are attacked electrophilically by percarboxylic acids II and III. The textile fibers are practically non-oxidizable ionically, since they either contain no or chemically deactivated double bonds.

Although there is a high activation energy barrier of 48 kcal / mol opposing the homolytic decomposition of the hydrogen peroxide formed as an intermediate or used directly as a bleaching agent, this reaction must be given special attention.

The homolysis of hydrogen peroxide is catalyzed by traces of heavy metal ions which are unavoidable in the washing process and can thus become the main reaction. Hydroxyl and perhydroxyl radicals act unselectively, also attack saturated substances, i. H. Textile fibers, and therefore bleach poorly.

According to W. Trieselt, Melliand Textilberichte 1970, 1094 the following reaction could occur:

The molecular oxygen produced in this example does not have a bleaching effect and leaves it Wash liquor as a gas. The intermediate radicals can attack the fibers. The catalyst system consisting of iron and copper ions constantly regenerates itself.

J. Dannacher and W. Schlenken, Textilveredlung 25, 205 (1990), however, say that the mechanism of textile bleaching has not yet been elucidated.

The formation of radicals from hydrogen peroxide can be masked by heavy metal ions z. B. can be suppressed with complexing agents. DE-OS 703 604 describes a process for stabilizing per compounds during textile washing by magnesium silicate. 0.2% to 1.5% magnesium silicate in detergents is recommended for stabilization and fiber protection.

Magnesium silicate is also used in detergents today. Its effect is through combination with ethylenediaminetetraacetate (EDTA) or phosphonates z. B. 1-Hydroxiethan-1,1-diphosphonic acid still increased. According to G. Jakobi and A. Löhr, Detergents and Textile Washing, VCH Verlagsgesellschaft, Weinheim 1987 p. 106, the general formulations for powdered heavy-duty detergents contain 0.2% - 0.5% EDTA or phosphonates as stabilizers. G. Jakobi and M. Schwuger, Chemiker-Zeitung 99, 182 (1975) describe that the biodegradability of EDTA and also 1-hydroxiethan-1,1-diphosphonic acid must be classified as low under the conditions of the "closed bottle test" . Recently, Ch. Gousetis et. al., Surfactants Surf. Det. 27, 41 (1990) Isoserine diacetic acid is presented as a new, biodegradable complexing agent for detergents and cleaning agents. The production of isoserine diacetic acid is technically very complex. DE-OS 23 39 888 describes the production and use of N, N-biscarboxymethyl-L-glutamic acid as a complexing agent for detergents. A large excess of chloroacetic acid is required in the manufacture of this product.

The object of the present invention was therefore to provide new, environmentally friendly bleach stabilizers which are technically easy to produce.

The problem was solved by using natural or biotechnologically easily produced amino acids.

The invention therefore relates to the use of natural materials or biotechnologically produced amino acids and / or their succinic acid amides and / or their maleic acid amides and / or their monocarboxymethylates in acid form or in the form of their alkali metal salts as bleach stabilizers.

Typical representatives are the substances L-glutamic acid IV, L-glutamic acid succinic acid amide V and L-glutamic acid, N-carboxymethyl-L-glutamic acid VI or their sodium salts listed in the formula:

It has surprisingly been found that the non-toxic natural products L-glutamic acid or L-aspartic acid and their succinic or maleic acid amides or monocarboxymethylate derivatives have a high activity as bleach stabilizers in the case of hydrogen peroxide or hydrogen peroxide-generating bleaching agents, in particular in the case of sodium perborate, in the presence of traces of heavy metal ions own the textile laundry. The compounds used according to the invention are effective in the wash liquor in a low concentration of 5-30 mg / l, preferably 10-20 mg / l. Another favorable property of L-glutamic acid or L-aspartic acid is its large-scale availability by means of biotechnical processes, which ensures easy and environmentally friendly production.

According to Römpp, Chemielexikon 9th edition, Vol. 2, p. 1606 (Thieme Verlag, 1990), L-glutamic acid or sodium L-glutamate can be isolated from protein hydrolysates or can be obtained on an industrial scale by fermentation of D-glucose and ammonia.

According to Römpp, Chemielexikon 9th edition, Vol. 1, p. 267 (Thieme Verlag, 1989), L-aspartic acid is technically accessible through chemical or biotechnological addition of ammonia to maleic or fumaric acid.

The aminodicarboxylic acids can be derivatized to aminotricarboxylic acids, for example by reacting L-glutamic acid with chloroacetic acid analogously to Example 12. The preparation of the succinic or maleic acid amides of L-glutamic acid is described in Examples 13-14. The reaction products are mixtures of substances which have been specified analytically and which were used directly as complexing agents without further work-up. It is advantageous to note that the implementation gen in water, which serves as a solvent for the products after the reaction.

The following examples 1-11 illustrate the mode of action of the claimed compounds on the basis of washing tests. For comparison, an example without stabilizer and one with EDTA as stabilizer were carried out in the test series.

Examples 1-6

In a Linitest laboratory washing machine, WFK cotton test fabrics with red wine soiling (11 x 18 cm) are washed for 30 minutes at 60 ° C in 250 ml washing solution and then rinsed and dried. The reflectance difference DR is determined spectrophotometrically at = = 560 nm with a photometer (Datacolor 3890) compared to an unwashed test fabric (Table 1).

• 438 mg Zeolith A (Wessalith P) / Cobuilder (Sokalan CP5) 9:1
• 81 mg Alkylbenzolsulfonat (Marlon A)
• 32 mg Fettalkoholoxethylat (Marlipal 013/100)
• 38 mg Kokosseife
• 213 mg Natriumsulfat
• 74 mg Natronwasserglas
• 171 mg Natriumperborat-tetrahydrat
• 24 mg Tetraacetylethylendiamin (TAED)
• 9 mg Magnesiumsilikat
• 2,3 mg Sabilisator nach Tabelle 1 (außer in Beispielen 1 und 6) Leitungswasser 13° dH ad 250 ml
• 5 ppm Kupfer (II)-ionen (außer in Beispiel 6).
  

The washing solutions had the following composition:

• 438 mg Zeolite A (Wessalith P) / Cobuilder (Sokalan CP5) 9: 1
• 81 mg alkylbenzenesulfonate (Marlon A)
• 32 mg fatty alcohol oxyethylate (Marlipal 013/100)
• 38 mg coconut soap
• 213 mg sodium sulfate
• 74 mg soda water glass
• 171 mg sodium perborate tetrahydrate
• 24 mg tetraacetylethylenediamine (TAED)
• 9 mg magnesium silicate
• 2.3 mg of stabilizer according to Table 1 (except in Examples 1 and 6) tap water 13 ° dH ad 250 ml
• 5 ppm copper (II) ions (except in example 6).
  

Examples 7-11

• 22,5 g Marlon A350 (= 11.25 g Alkylbenzolsufonat)
• 6,0 g Marlipal 24/70 (Kokosfettalkoholoxethylat)
• 4,2 g Edenor W35 (Pulverseife)
• 37,5 g Wessalith P (Zeolith A)
• 6,0 g Sokalan CP5 (Acrylsäure/Maleinsäure-Copolymerisat)
• 15,0 g Soda
• 4,5 g Natriummetasilikat pentahydrat
• 1,5 g Carboximethylcellulose
• 30,0 g Natriumsulfatdekahydrat
• 0,7 g Savinase (Enzym)
• 30,0 g Natriumperborat-tetrahydrat
• 4,5 g Tetraacetylethylendiamin (TAED)
• 0,3 g Stabilisator nach Tabelle 2 (außer in Beispiel 7) Wasser ad 500 ml

In a household washing machine (Bosch V 630), 4 kg of white cotton ballast fabric are washed together with WFK cotton test fabric with tea soiling at a washing temperature of 60 ° (45 min main wash and 35 min rinse cycle). After loading the washing machine with the laundry, 10 ml of a 2.7% copper II chloride dihydrate solution and the detergent with the following composition were added to the incoming tap water stream (13 "dH):

• 22.5 g Marlon A350 (= 11.25 g alkylbenzenesulfonate)
• 6.0 g Marlipal 24/70 (coconut fatty alcohol oxyethylate)
• 4.2 g Edenor W35 (powder soap)
• 37.5 g Wessalith P (zeolite A)
• 6.0 g Sokalan CP5 (acrylic acid / maleic acid copolymer)
• 15.0 g of soda
• 4.5 g sodium metasilicate pentahydrate
• 1.5 g carboxymethyl cellulose
• 30.0 g sodium sulfate decahydrate
• 0.7 g savinase (enzyme)
• 30.0 g sodium perborate tetrahydrate
• 4.5 g tetraacetylethylenediamine (TAED)
• 0.3 g stabilizer according to Table 2 (except in Example 7) water ad 500 ml

After the wash program has ended, the test fabric is dried and the remission difference DR Determined spectrophotometrically at = = 560 nm with a photometer (Datacolor 3890) against unwashed test fabric. The values are in Table 2.

Example 12: N-carboxymethyl-L-glutamic acid disodium salt

• Ausbeute: 388 g klare wäßrige Lösung, pH = 6,7
• Wirkstoffgehalt: 32 %, NaCl 7,5 %

84.55 g of monosodium L-glutamate are dissolved in 76.2 g of water and 60 g of 40% sodium hydroxide solution in a stirred flask with an internal thermometer. The mixture is heated to 70 ° C. Within 20 minutes a solution of 47.25 g of chloroacetic acid in 80 g of water is added dropwise. Finally, 40 g of 40% sodium hydroxide solution are added and the mixture is stirred at 70 ° C. for 3 hours.

• Yield: 388 g of clear aqueous solution, pH = 6.7
• Active substance content: 32%, NaCl 7.5%

Example 13: L-glutamic acid succinic acid trisodium salt

352 g of water are placed in a stirred flask with an internal thermometer and reflux condenser, 160 g of 50% sodium hydroxide solution are added and 169 g of monosodium L-glutamate are dissolved therein. The batch is heated to 60 ° C. Within 3 min. 100 g of succinic anhydride are added in portions. During the addition, the temperature rises to 80 ° C. Finally, the mixture is stirred at 60 ° C. for 1 h.

Yield: 781 g of clear aqueous solution.

According to 1 H-NMR spectroscopic analysis (250 MHz, D ₂ 0), the composition of the solution results from the evaluation of the integrals of the 2-H of glutamic acid (dd, δ = 3.7 ppm) and the amide (dd , δ = 4.1 ppm). In this case an L-glutamate: amide ratio of 7.9: 13.0 is obtained. This corresponds to the following product distribution in the solution: 195 g of L-glutamic acid succinic acid trisodium salt, 72 g of disodium L-glutamate and 61 g of disodium succinate.

Example 14: L-glutamic acid maleic acid trisodium salt

The procedure is as in Example 13 with the following amounts of substance: 360 g of water, 160 g of 50% sodium hydroxide solution, 169 g of monosodium L-glutamate and 98 g of maleic anhydride.

Yield: 787 g of clear aqueous solution.

The signal distribution of 12:21 results in the following product distribution in the solution: 198 g L-glutamic acid maleinamide trisodium salt, 70 g L-glutamic acid disodium salt and 58 g disodium maleinate.

Claims (5)

1. Use of amino acids isolated from natural material or produced biotechnologically and / or their succinic and / or their maleic amides and / or their monocarboxymethylates in acid form or in the form of their alkali metal salts as bleach stabilizers. 2. Use of naturally or biotechnologically produced amino acids according to claim 1, characterized in that
that L-glutamic and / or L-aspartic acid are used as amino acids. 3. Use of naturally or biotechnologically produced amino acids according to claims 1 or 2,
characterized,
that the compounds are used in detergents containing sodium perborate. 4. Use of naturally or biotechnologically produced amino acids according to claims 1 to 3,
characterized,
that the concentration in the wash liquor is 5 - 30 mg / l. 5. Process for commercial textile washing,
characterized,
that compounds according to claims 1 or 2 are added to the wash liquor and these are present during a bleaching process with sodium perborate and / or hydrogen peroxide.