EP0998546B1 - Use of electrolyte mixtures as sequestering agents - Google Patents

Abstract

The invention relates to the use of electrolyte mixtures containing (a) phosphonates and (b) at least one other electrolyte salt selected from the group made up of polyacrylates, silicates, carbonates and citrates, as sequestering agents for producing aqueous bleaching agents. Preparations which protect the fabric from yellowing, preferably chlorine bleaching solutions are obtained, especially together with chlorine-resistant tensides.

Description

Field of the Invention

The invention relates to the use of certain electrolyte mixtures in laundry aqueous bleaches.

State of the art

While heavily soiled textiles for washing in many European countries are powdery or liquid Heavy duty detergents are used that only reach their performance at higher temperatures, For example, consumers in the U.S. and Spain prefer cold wash, where, in addition to a detergent to remove particularly difficult stains, a liquid Bleach, preferably based on hypochlorite, is added.

A large number of liquid bleaching agents are known from the prior art. For example, EP-A 0274885 (ICI) recommends the use of mixtures of linear and branched amine oxides for the production of viscous hypochlorite bleaches. According to the teaching of EP-A 0145084 (Unilever), mixtures of amine oxides with soaps, sarcosinates, taurides or sugar esters can also be used for this purpose. EP-A 0137551 and EP-A 0447261 (Unilever) disclose the use of amine oxides with soap or sarcosinate and other anionic surfactants, for example alkyl sulfates, alkyl ether sulfates, secondary alkane sulfonates or alkylbenzenesulfonates as thickening components for hypochlorite solutions. EP-A1 0447261 aqueous bleaching agent compositions containing sodium hypochlorite and anionic surfactants are also known. However, the hypochlorite concentration of these agents is 0.1 to 8% by weight of active chlorine. In German patent DE-C1 4333100 , the applicant finally has chlorine bleaching solutions based on hypochlorites, fatty alcohol ether sulfates, Amine oxides and amine oxide phosphonic acids are proposed. The use of silicates or carbonates as buffers in chlorine bleaching liquors can be found, for example, in the publications US Pat. No. 4,623,476 (Procter & Gamble) and EP-A1 0079102 and EP-A1 0137551 (Unilever).

High demands are placed on bleaches of the type mentioned: consumers have to be textile compatible, i.e. by treatment with the intrinsically aggressive chemical hypochlorite the stains must be removed without attacking the tissue. Because skin contact with the bleach is not excluded, the preparations must also be as dermatologically tolerated as possible just be possible. A particular problem is that hypochlorite solutions also contain metals attack and the loosened metal traces are deposited on the textile fibers during washing can, which is ultimately reflected in the yellowing of the fabric. Try means of the market to prevent this redeposition by the use of silicates has been shown in practice however, this measure is not always satisfactory.

Accordingly, the complex object of the invention has been the yellowing of the laundry counteract by the influence of heavy metal ions and available sequestrants places that allow the production of aqueous bleaches, especially chlorine bleach, which are at the same time chlorine-stable, gentle on textiles and as skin-friendly as possible are sufficient have high viscosity and with high stain removal capacity, the deposition of Prevent metal traces on the fabric reliably.

Description of the invention

(a) Phosphonate ausgewählt aus den anorganischen Phosphonaten, die der Formel (I) folgen, HP(O)(OM¹)₂    (I) in der M für ein Alkali- oder Erdalkalimetall, Aluminium oder Zink steht, und den organischen Phosphonaten, die der Formel (II) folgen, R¹P(O)(OR²)₂    (II) in der R¹ und R² unabhängig voneinander für Wasserstoff oder lineare oder verzweigte, Kohlenwasserstoffreste mit 4 bis 12 Kohlenstoffatomen stehen, mit der Maßgabe, daß R¹ und R² nicht gleichzeitig Wasserstoff bedeuten können, und

(b) mindestens ein weiteres Elektrolytsalz ausgewählt aus der Gruppe, die gebildet wird von Polyacrylaten, Silicaten und Carbonaten,

zur Verminderung der Ablagerung von Metallen auf dem Gewebe während der Wäsche mit wäßrigen Bleichmitteln mit einem behalten Alkalihypochlorit.The invention relates to the use of electrolyte mixtures containing

(a) phosphonates selected from the inorganic phosphonates which follow the formula (I) , HP (O) (OM ¹ ) ₂ (I) in which M represents an alkali or alkaline earth metal, aluminum or zinc, and the organic phosphonates which follow the formula (II) , R ¹ P (O) (OR ² ) ₂ (II) in which R ¹ and R ² independently of one another represent hydrogen or linear or branched, hydrocarbon radicals having 4 to 12 carbon atoms, with the proviso that R ¹ and R ² cannot simultaneously denote hydrogen, and

(b) at least one further electrolyte salt selected from the group formed by polyacrylates, silicates and carbonates,

to reduce the deposition of metals on the fabric during washing with aqueous bleaches with a retained alkali hypochlorite.

Surprisingly, it was found that the addition of small amounts of the electrolyte mixtures mentioned to hypochlorite solutions, the deposition of metals significantly reduced on the fabric during washing and counteracts the yellowing of the fibers. The invention includes the finding that the use of mild, chlorine-stable Surfactants such as preferably alkyl ether sulfates, amine oxides, alkyl and / or alkenyl oligoglycosides and Fatty acid salts to further improve the stabilization against yellowing, the cleaning performance and dermatological tolerance. The funds finally point have a sufficiently high viscosity so that metering by the consumer is problem-free is possible.

phosphonates

For the purposes of the invention, the term phosphonates includes both inorganic phosphonates (also known as secondary phosphites) of the formula (I), HP (O) (OM ¹ ) ₂ (I) in which M represents an alkali or alkaline earth metal, aluminum or zinc, preferably sodium, and also organic phosphonates of the formula (II) , R ¹ P (O) (OR ² ) ₂ (II) in which R ¹ and R ² independently of one another represent hydrogen or linear or branched hydrocarbon radicals having 4 to 12 carbon atoms, with the proviso that R ¹ and R ² cannot simultaneously denote hydrogen. Typical examples of inorganic phosphonates are sodium phosphonate (= sodium phosphite), calcium phosphonate (= calcium phosphite) and zinc phosphonate (= zinc phosphite). Regarding the production and properties of these compounds cf. Holleman-Wiberg, Textbook of Inorganic Chemistry, Walter de Gruyter, Berlin, 81.-90. Edition, 1976, pp. 458/459 . Examples of organic phosphonates are butyl phosphonate and 2-ethylhexyl phosphonate.

alkali metal hypochlorites

The aqueous bleaching agent is chlorine bleaching solutions containing alkali hypochlorite. Alkali hypochlorites include lithium, To understand potassium and especially sodium hypochlorite. The hypochlorites can be found in amounts of 1.5 to 10, preferably 2 to 8 and in particular 4 to 6% by weight, based on the composition, are used become.

electrolyte salts

The phosphonates are used together with at least one other electrolyte salt. in this connection can be alkali and / or alkaline earth silicates, carbonates or mixtures thereof; typical examples are sodium silicate, potassium silicate, sodium carbonate, potassium carbonate. In a preferred embodiment of the invention are used as electrolyte salts Polyelectrolytes of the polyacrylate type used. These include not only the homopolymers acrylic acid, but also methacrylic acid and its esters with lower linear or to understand branched alcohols with 1 to 8 carbons. The generic term polyacrylates also includes the copolymers of the substances mentioned. The average molecular weight of the Polyacrylates can spread over a wide range and are preferably between 300 and 5,000,000 1,000 to 1,000,000, in particular 50,000 to 500,000 and particularly preferably 100,000 to 250,000 daltons. The electrolyte salts support the sequestering action of the phosphonates and ensure that the preparations have a constantly high alkaline pH in the range from 10 to 14. The phosphonates and the electrolyte salts can be in a weight ratio of 95: 5 to 5:95, preferably 80: 20 to 20 80 and in particular 60: 40 to 40: 60 can be used. The amount used the electrolyte mixtures containing phosphonates and electrolyte salts can be 0.01 to 5, preferably 0.1 to 2 and in particular 0.5 to 1% by weight, based on the composition.

Chlorine stable surfactants

(a) Alkyl ether sulfates. Alkyl ether sulfates are known anionic surfactants which are obtained by sulfation of nonionic surfactants of the alkyl polyglycol ether type and subsequent neutralization. The alkyl ether sulfates which are suitable for the purposes of the agents according to the invention follow the formula (III) R ³ O- (CH ₂ CH ₂ O) _q SO ₃ X (III) in which R ^{3 represents} an alkyl radical having 12 to 18, in particular 12 to 14, carbon atoms, q represents numbers 2 to 5, in particular 2 to 3 and X represents sodium or potassium. Typical examples are the sodium salts of sulfates of the C _12/14 cocoalcohol-2, -2,3- and -3-EO adduct. The alkyl ether sulfates can have a conventional or narrow homolog distribution. The alkyl ether sulfates are preferably used in amounts of 1 to 8, preferably 1.5 to 6 and in particular 2 to 4% by weight, based on the composition.

(b) amine oxides. Amine oxides are also known substances, which are occasionally attributed to the cationic, but usually the nonionic surfactants. They are prepared from tertiary fatty amines, which usually have either one long and two short or two long and one short alkyl radical, and are oxidized in the presence of hydrogen peroxide. The amine oxides which are suitable for the purposes of the invention follow the formula (IV)

in which R ^{4 represents} a linear or branched alkyl radical having 12 to 18 carbon atoms and R ⁵ and R ⁶ independently of one another are R ⁴ or an optionally hydroxy-substituted alkyl radical having 1 to 4 carbon atoms. Amine oxides of the formula (IV) in which R ⁴ and R ^{5 are} C _12/14 and C _12/18 cocoalkyl radicals and R ^{6 is} a methyl or a hydroxyethyl radical are preferably used. Also preferred are amine oxides of the formula (IV) in which R ^{4 is} a C _12/14 or C _12/18 cocoalkyl radical and R ⁵ and R ⁶ are methyl or hydroxyethyl radicals. The amine oxides are usually used in amounts of 0.5 to 5, preferably 1 to 4,% by weight, based on the composition.

(c) alkyl and / or alkenyl oligoglycosides. Alkyl and alkenyl oligoglycosides are known nonionic surfactants which follow the formula (V) R ⁷ O- [G] _p (V) in which R ^{7 represents} an alkyl and / or alkenyl radical having 4 to 22 carbon atoms, G represents a sugar radical having 5 or 6 carbon atoms and p represents numbers from 1 to 10. They can be obtained according to the relevant procedures in preparative organic chemistry. As a representative of the extensive literature, reference is made here to the documents EP-A1 0301298 and WO 90/03977 . The alkyl and / or alkenyl oligoglycosides can be derived from aldoses or ketoses with 5 or 6 carbon atoms, preferably glucose. The preferred alkyl and / or alkenyl oligoglycosides are thus alkyl and / or alkenyl oligo glucosides . The index number p in the general formula (V) indicates the degree of oligomerization (DP), ie the distribution of mono- and oligoglycosides, and stands for a number between 1 and 10. While p must always be an integer in a given compound and especially here can assume the values p = 1 to 6, the value p for a specific alkyl oligoglycoside is an analytically determined arithmetic parameter, which usually represents a fractional number. Alkyl and / or alkenyl oligoglycosides with an average degree of oligomerization p of 1.1 to 3.0 are preferably used. From an application point of view, preference is given to those alkyl and / or alkenyl oligoglycosides whose degree of oligomerization is less than 1.7 and is in particular between 1.2 and 1.4. The alkyl or alkenyl radical R ⁷ can be derived from primary alcohols having 4 to 11, preferably 8 to 10, carbon atoms. Typical examples are butanol, capro alcohol, caprylic alcohol, capric alcohol and undecyl alcohol and their technical mixtures, such as are obtained, for example, in the hydrogenation of technical fatty acid methyl esters or in the course of the hydrogenation of aldehydes from Roelen's oxosynthesis. Alkyl oligoglucosides of chain length C ₈ -C ₁₀ (DP = 1 to 3) are preferred, which are obtained as a preliminary step in the separation of technical C ₈ -C ₁₈ coconut fatty alcohol by distillation and with a proportion of less than 6% by weight of C ₁₂ - Alcohol can be contaminated and alkyl oligoglucosides based on technical C _9/11 oxo alcohols (DP = 1 to 3). The alkyl or alkenyl radical R ⁷ can also be derived from primary alcohols having 12 to 22, preferably 12 to 14, carbon atoms. Typical examples are lauryl alcohol, myristyl alcohol, cetyl alcohol, palmoleyl alcohol, stearyl alcohol, isostearyl alcohol, oleyl alcohol, elaidyl alcohol, petroselinyl alcohol, arachyl alcohol, gadoleyl alcohol, behenyl alcohol, erucyl alcohol, brassidyl alcohol and their technical mixtures, which can be obtained as described above. Alkyl oligoglucosides based on hardened C _12/14 coconut alcohol with a DP of 1 to 3 are preferred. The glycosides are preferably used in amounts of 1.5 to 6, preferably 2 to 4% by weight, based on the composition.

(d) fatty acid salts. The agents according to the invention can contain fatty acid salts of the formula (VI) as further surfactants, R ⁸ CO-OX (VI) in which R ⁸ CO represents an acyl radical having 12 to 22 carbon atoms and X represents an alkali metal. Typical examples are the sodium and / or potassium salts of lauric acid, myristic acid, palmitic acid, palmoleic acid, stearic acid, isostearic acid, oleic acid, elaidic acid, petroselinic acid, linoleic acid, linolenic acid, elaeostearic acid, arachic acid, gadoleic acid, behenic acid and erucic acid and their mixtures, and their mixtures the pressure splitting of technical fats and oils. Salts of technical coconut or tallow fatty acids are preferably used. Since the formulations according to the invention are strongly alkaline, it is also possible to use the fatty acids instead of the salts, which are neutralized in situ when introduced into the mixture. Those agents according to the invention preferably contain, as an optional component, fatty acid salts in which a particular low foam level is desired. The soaps are preferably used in amounts of 1.5 to 6, preferably 2 to 4% by weight, based on the composition.

Industrial applicability

The bleaches obtainable using the electrolyte mixtures according to the invention have usually a non-aqueous content of 5 to 35 and preferably 8 to 15 wt .-% on and are preferably suitable for the treatment of textile fabrics, such as yarns, Fabric and especially textiles. They are usually used at low levels Temperatures, i.e. in the cold wash area (approx. 15 to 25 ° C). The funds are not just outstanding with excellent stain removal, but reliably prevent the deposition of Traces of metal on the fibers and thus also prevent yellowing. Although the real one Use of the agent aimed at removing stains during washing, they are suitable basically also for other purposes in which hypochlarite solutions are used, for example for cleaning and disinfecting hard surfaces.

Additional auxiliaries and additives include, for example, other chlorine-stable surfactants or hydrotropes such as alkyl sulfates, alkyl sulfonates, alkyl benzene sulfonates, xyloisulfonates, sarcosinates, Taurides, isethionates, sulfosuccinates, betaines, sugar esters, fatty alcohol polyglycol ethers and fatty acid N-alkyl glucamides. The sum of all surfactants preferably makes at most 10 to 15% by weight. the total amount of ingredients in the recipe. The agents according to the invention can Contain alkali metal compounds, preferably sodium hydroxide or potassium hydroxide, with their help the pH of the recipes to an optimal value of 10 to 14, preferably 12.5 to 13.5 can be adjusted.

In addition, the agents can contain active chlorine-stable fragrances, optical brighteners, dyes and pigments in a total amount of 0.01 to 0.5% by weight, based on the agents. The fragrances known to be active chlorine-resistant include, for example, monocyclic and bicyclic monoterpene alcohols and their esters with acetic or propionic acid (for example isoborneal, dihydroterpene oil, isobomylacetate, dihydroterpenylacetate). Other fragrances that come into consideration for this purpose are mentioned, for example, in documents EP-A1 0622451 (Procter & Gamble) and JP-A Sho 62/89800 (Raison). The optical brighteners can be, for example, the potassium salt of 4,4'-bis (1,2,3-triazolyl) - (2 -) - stilbin-2,2-sulfonic acid, which is sold under the Phorwite® BHC brand 766 is distributed. Possible color pigments include green chlorophthalocyanines (Pigmosol® Green, Hostaphine® Green) or yellow Solar Yellow BG 300 (Sandoz). The preparation is made by stirring. If necessary, the product obtained can be decanted or filtered to remove foreign bodies and / or agglomerates. The agents also have a viscosity above 100 mPas - measured at 20 ° C in a Brookfield viscometer.

Examples

To investigate the bleaching effect, soiled fabric was treated with various chlorine bleaches. The yellowing of the tissue was determined photometrically, the initial value of the soiled tissue serving as the standard (100%). The measurements were carried out in a liquor with a metal ion content of 300 ppb Fe and 100 ppb Mn; the water hardness was 1000 ppm CaCl ₂ , the hydrogen carbonate content was 0.013% by weight. The liquor ratio (tissue: water) was 1:50, the exposure time was 30 minutes at a temperature of 40 ° C. The results are summarized in Table 1; the quantities are understood as% by weight. Examples 1 to 6 are according to the invention, examples V1 and V2 serve for comparison.

Claims (8)

1. The use of electrolyte mixtures containing

   (a) phosphonates selected from inorganic phosphonates corresponding to formula (I): HP(O)(OM¹)₂ in which M is an alkali metal or alkaline earth metal, aluminium or zinc, and organic phosphonates corresponding to formula (II): R¹P(O)(OR²)₂ in which R¹ and R² independently of one another represent hydrogen or linear or branched C_4-12 hydrocarbon radicals, with the proviso that R¹ and R² cannot both be hydrogen,
   and

   (b) at least one other electrolyte salt selected from the group consisting of polyacrylates, silicates and carbonates,

   for reducing the deposition of metals on fabrics during washing with water-based bleaching compositions containing alkali metal hypochlorite.
2. The use claimed in claim 1, characterized in that homo- or copolymers of acrylic acid, methacrylic acid and esters thereof with lower, linear or branched C_1-18 alcohols are used as the polyelectrolyte salts
3. The use claimed in claim 2, characterized in that polyacrylates with an average molecular weight of 300 to 5,000,000 dalton are used.
4. The use claimed in claims 1 to 3, characterized in that sodium silicate, potassium silicate, sodium carbonate, potassium carbonate or mixtures thereof are used as the electrolyte salts.
5. The use claimed in claims 1 to 4, characterized in that the phosphonates and the electrolyte salts are used in a ratio by weight of 95:5 to 5:95.
6. The use claimed in claims 1 to 5, characterized in that the electrolyte mixtures are used in quantities of 0.01 to 5% by weight, based on the water-containing bleaching compositions.
7. The use claimed in claims 1 to 6, characterized in that the electrolyte mixtures are used together with chlorine-stable surfactants selected from the group consisting of alkyl ether sulfates, amine oxides, alkyl and/or alkenyl oligoglycosides and/or fatty acid salts.
8. The use claimed in claims 1 to 7, characterized in that the electrolyte mixtures are used together with chlorine-stable perfumes.