SK562000A3 - 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

Technical field

The invention relates to the use of electrolyte mixtures as sequestering agents in the manufacture of aqueous bleaching compositions.

BACKGROUND OF THE INVENTION

While in many European countries, washing of heavily soiled fabrics uses powdery or liquid detergents whose performance is only achieved at higher temperatures, consumers in the US and Spain, for example, prefer cold washing where they are added to the wash to remove very difficult stains and a bleaching agent, in particular based on hypochlorite.

Many liquid bleaching agents are known in the art. For example, EP-A-0274885 (ICI) recommends the use of a mixture of linear and branched amine oxides in the manufacture of viscous hypochlorite bleaching compositions. 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 a soap or sarcosinate and other anionic surfactants, for example alkyl sulfates, alkyl ether sulfates, secondary alkanesulfonates or alkyl benzene sulfonates as a thickening agent for the thickening agent. Further, EP-A1 0447261 discloses aqueous bleaching compositions containing sodium hypochlorite and anionic surfactants. However, the hypochlorite concentration in this composition is 0.1 to 8 wt. of active chlorine. DE-C1 4333100 finally describes chlorine bleaching liquors based on hypochlorite, fatty alcohol ether sulfates, amine oxides and amine oxide phosphonic acids. The use of silicates or carbonates as a buffer in chlorine bleaching liquids is disclosed

For example, US 4,623,476 (Procter & Gamble) as well as EP-A1 0079102 and EP-A1 0137551 (Unilever).

Consumers place high demands on the bleaching agent of this kind: they must be compatible with textiles, i.e. j. treatment with aggressive chemical hypochlorite must remove stains without breaking the fabric. Since skin contact with the bleaching agent is not excluded, the preparations must be as dermatologically compatible as possible. A particular problem is that hypochlorite solutions also attack metals and the dissolved traces of metals can settle on the fibers of the fabric during washing, which can subsequently cause the fabric to yellow. Although preparations on the market attempt to prevent such deposition by the common use of silicates, in practice this measure is not always satisfactory.

Consequently, the complex object of the present invention was to counteract the yellowing of laundry by heavy metal ions and to provide a sequestering agent allowing the production of aqueous bleaching agents, in particular chlorine bleaching liquids, which are simultaneously chlorine-stable, protect textiles and are high viscosity and high stain removal capability reliably prevent metal traces from settling on the fabric.

SUMMARY OF THE INVENTION

The present invention is based on the use of electrolyte-containing mixtures

(a) phosphonates; and

(b) at least one other electrolyte salt selected from the group consisting of polyacrylates, silicates, carbonates and citrates as sequestering agents in the manufacture of aqueous bleaching compositions.

Surprisingly, it has been found that the addition of a small amount of said electrolyte mixtures to an aqueous bleaching agent, in particular to a hypochlorite solution, significantly reduces the deposition of metals on the fabric during washing and counteracts the yellowing of the fibers. The invention includes the finding that the combined use of fine chlorine-stable surfactants such as, in particular, alkyl ether sulfates, amine oxides, alkyl and / or alkenyl oligoglycosides and fatty acid salts leads to a further improvement

-3stabilization against yellowing, cleansing performance and dermatological tolerance. Finally, the compositions according to the invention have a sufficiently high viscosity such that dosing by the consumer is problem-free.

phosphonates

For the purposes of the present invention, phosphonates are inorganic phosphonates (also known as secondary phosphonates) of formula I,

HP (O) (OM ¹ ) ₂ (I) wherein M is an alkali metal, an alkaline earth metal, aluminum or zinc, especially sodium, and organic phosphonates of formula II,

R ¹ P (O) (OR ² ) ₂ (II) wherein R ¹ and R ² are independently from each other hydrogen or a linear or branched hydrocarbon radical having 1 to 22, in particular 4 to 12, carbon atoms, optionally containing functional groups thereto R ¹ and R ² are not simultaneously hydrogen. Typical examples of inorganic phosphonates are sodium phosphite, calcium phosphite and zinc phosphite. Regarding the production and properties of these compounds, compare Holleman-Wiberg, Lehrbuch der Anorganischen Chemie, Walter de Gruyter, Berlin, 81-90th edition, 1976, page 458/459. Examples of organic phosphonates are methylphosphonate, ethylphosphonate, butylphosphonate, 2-ethylhexylphosphonate as well as amine group phosphonates such as aminomethylene phosphonate or aminoethylene phosphonate. Further suitable phosphonates are compounds which are linked to one another by functional groups such as nitrilotris (methylene phosphonate) or nitrilotris (ethylene phosphonate).

Alkaline hypochlorites

The aqueous bleaching compositions may contain hydrogen peroxide, but are preferably chlorine bleaching liquors containing an alkaline hypochlorite. Alkali hypochlorite is understood to mean lithium, potassium and especially sodium hypochlorite. Chlórnany je

% Can be used in amounts of from 1.5 to 10, more preferably from 2 to 8 and in particular from 4 to 6% by weight. relative to the device.

Salts of electrolytes

The phosphonates are used together with at least one other electrolyte salt. These may be alkali metal or alkaline earth metal silicates, carbonates, citrates, or mixtures thereof; typical examples are sodium silicate, potassium silicate, sodium carbonate, potassium carbonate, sodium citrate, potassium citrate, magnesium citrate. In a more preferred embodiment, polyacrylate-type polyelectrolytes are used as electrolyte salts. These are not only homopolymers of acrylic acid, but also methacrylic acid as well as esters of lower linear or branched alcohols having 1 to 8 carbon atoms. The generic term polyacrylates also includes copolymers of said materials. The average molecular weight of the polyacrylates can be dispersed over a wide range and is from 300 to 5,000,000, more preferably from 1,000 to 1,000,000, in particular from 50,000 to 500,000, and in particular from 100,000 to 250,000 daltons. Electrolyte salts promote the sequestering effect of phosphonates and guarantee that the formulation has a constant, highly alkaline pH value in the range of from 10 to 14. Phosphonates and electrolyte salts may be used in a weight ratio of 95: 5 to 5:95, more preferably 80:20 to 20: 80, and in particular 60:40 to 40:60. The amount of phosphonate-containing electrolyte mixtures used may be from 0.01 to 5, more preferably from 0.1 to 2, and in particular from 0.5 to 1% by weight. relative to the device.

I _t

Chloride-stable surfactants

(a) Alkyl ether sulphates

Alkyl ether sulfates are known anionic surfactants which can be obtained by sulfating nonionic surfactants of the alkyl polyglycol ether type and subsequent neutralization. In the composition according to the invention, the suitable alkyl ether sulfates have the formula III,

-5R ³ O- (CH ₂ CH ₂ O) _q SO ₃ X (III) wherein R ³ represents an alkyl radical having 12 to 18, more preferably 12 to 14 carbon atoms, q is a number from 2 to 5, in particular 2 to 3 and X is sodium or potassium. Typical examples are the sodium salts of the C _12/14 -cocoalcohol-2,3-and-EO-adduct sulphates. The alkyl ether sulfates may have a conventional or narrow distribution of homologs. It is preferred to use alkyl ether sulfates in an amount of from 1 to 8, more preferably from 1.5 to 6, and in particular from 2 to 4% by weight. relative to the device.

(b) Amine oxides

Also, amine oxides are known substances which are occasionally ranked as cationic, but generally nonionic surfactants. They are prepared from tertiary fatty amines, which generally have either one long and two short or two long and one short alkyl radicals and are oxidized in the presence of hydrogen peroxide. Within the meaning of the invention, the amine oxides to be considered have the formula IV,

R ⁵

I

R ⁴ - N -> O (IV)

I

R ⁶ wherein R ⁴ represents a linear or branched alkyl radical having 12 to 18 carbon atoms as well as R ⁵ and R ⁶ independently of each other denote R ⁴ or an alkyl radical having 1 to 4 carbon atoms optionally hydroxy-substituted. Preferred is the use of amine oxides of the formula (IV) in which R ⁴ and R ⁵ are C 12/14 or C 12/18 -cocoalkyl groups and R ⁸ is a methyl or hydroxyethyl radical. Also preferred are amine oxides of formula (IV) wherein R ⁴ is C 12/14 or C _12/18 -cycloalkyl and R ⁵ and R ⁶ are methyl or hydroxyethyl radicals. The amine oxides are generally used in an amount of from 0.5 to 5, preferably from 1 to 4% by weight. relative to the device.

-6c) Alkyl- and / or alkenyloligoglycosides

Alkyl- and / or alkenyloligoglycosides are known nonionic surfactants having the formula V,

R ⁷ O- [G] _P '(V) wherein R ⁷ represents an alkyl and / or alkenyl radical having 4 to 22 carbon atoms, G is a sugar radical having 5 or 6 carbon atoms, and is a number from 1 to 10. It is possible they can be obtained by an appropriate preparative organic chemistry procedure. Representative for the extensive literature is referred to EP-A1 0301298 and WO 90/03977. The alkyl and / or alkenyl oligoglycosides can be derived from aldoses or ketoses having 5 or 6 carbon atoms, in particular glucose. Preferred alkyl and / or alkenyloligoglycosides are thus alkyl and / or alkenyloligoglucosides. The index number p in the general formula V indicates the degree of oligomerization (DP), i.e. the distribution of mono- and oligoglycosides and means a number from 1 to 10. While p in a given compound must be an integer and here in particular have a value of p = 1 to 6 p value for a certain alkyloligoglycoside is an analytically determined calculated quantity, which is usually a fraction. Preference is given to using alkyl- and / or alkenyloligoglycosides having a mean degree of oligomerization of p from 1.1 to 3.0. Preferred for use are those alkyl- and / or alkenyloligoglycosides whose degree of oligomerization is less than 1.7, and in particular has a value of from 1.2 to 1.4. The alkyl or alkenyl radical R @ ⁷ may be derived from primary alcohols having from 4 to 11, preferably from 8 to 10, carbon atoms. Typical examples are butanol, caproalcohol, caprylalcohol, caprinal alcohol and undecyl alcohol as well as technical mixtures thereof, such as can be obtained, for example, in the hydrogenation of industrial fatty acid methyl esters or during the hydrogenation of aldehydes in Roelen oxosynthesis. Preferred are alkyl chain oligos having Cs-C10 chain length (DP = 1 to 3), which are formed by distillation of the technical C8-C18-coconut fatty alcohol and may be contaminated with less than 6 wt. C12-alcohols as well as alkyl oligo-glucosides based on industrial C9 / 11-oxoalcohols (DP = 1 to 3). The alkyl or alkenyl radical R ⁷ may further be derived from primary alcohols having 12 to 22, more 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, petrozelinyl alcohol, arachyl alcohol, gadoleyl alcohol, behenyl alcohol, erucyl alcohol, brassidyl alcohol as well as the technical mixtures thereof described above. Preferred are C12 / 14-cocohole-alkyloligoglucosides having a DP of from 1 to 3. Preference is given to using glycosides in amounts of from 1.5 to 6, more preferably from 2 to 4% by weight. relative to the device.

d) Salts of fatty acids

As further surfactants, the compositions of the invention may contain fatty acid salts of formula VI,

R ⁸ CO-OX (VI) wherein R ⁸ CO is an acyl radical of 12 to 22 carbon atoms and X is an alkali metal. Typical examples are the sodium and / or potassium salts of lauric acid, myristic acid, palmitic acid, palmitoolic acid, stearic acid, isostearic acid, oleic acid, elaidic acid, petrozelinic acid, linoleic acid, linolenic acid, elaeostearic acid, arachic acid, gadoleic acid. , behenic acid and erucic acid, as well as their technical mixtures, such as those formed by pressure digestion of industrial fats and oils. Preference is given to the use of salts of technical coconut or tallow fatty acid. Since the formulations of the invention are strongly alkaline, it is possible to use fatty acids instead of salts which, when added to the mixture, are neutralized in situ. The compositions according to the invention in which particularly low foaming is desired preferably contain fatty acid salts as optional ingredients. Preference is given to the use of soaps in amounts of from 1.5 to 6, more preferably from 2 to 4% by weight. relative to the device.

Industrial usability

The bleaching compositions obtained using the electrolyte compositions of the invention generally have a non-aqueous proportion of from 5 to 35, and more preferably from 8 to 15 wt. and are suitable for the treatment of textile products such as yarns, fabric belts and especially textiles. Usually their use at low temperatures, i. in the field of cold washing

-8 (about 15-25 ° C). The compositions are not only excellent in stain removal, but also reliably prevent metal traces from settling on the fibers and thus prevent yellowing. Although the actual use of the compositions is to wash stains, they are also well suited for other purposes where hypochlorite solutions are used, for example, for cleaning and disinfecting hard surfaces.

Further auxiliaries and additives which may be used are, for example, other chlorine-stable surfactants and / or hydrotropes, such as alkyl sulfates, alkyl sulfonates, alkylbenzenesulfonates, xylolsulfonates, sarcosinates, taurides, isothionates, sulfosuccinates, betaines, sugar esters, fatty acid polyglycol ether fatty alcohol . It is preferred that the sum of all surfactants is at most 10-15% by weight. the total amount of ingredients in the recipe. The compositions according to the invention may contain alkali metal compounds, in particular sodium hydroxide or potassium hydroxide, by means of which the pH of the formulation can be adjusted to an optimum value of 10 to 14, more preferably 12.5 to 13.5.

In addition, the compositions may contain chlorine-active fragrances, optical brighteners, dyes and pigments in amounts from 0.01 to 0.5% by weight in total. relative to the device. Known active chlorine-stable fragrances include, for example, monocyclic and bicyclic monoterpene alcohols as well as their esters with acetic or propionic acid (e.g., isoborneal, dihydroterpene oil, isobornyl octane, dihydroterpenylacetane). Other suitable fragrances are mentioned, for example, in EP-A1 0622451 (Procter & Gamble) and JP-A Sho 62/89800 (Raison). Optical brighteners can be, for example, the potassium salt of 4,4'-bis- (1,2,3-triazolyl) - (2 -) - stilbine-2,2-sulfonic acid, which is distributed under the Phorwite® BHC 766 brand. colored pigments can be used among others green chlorophthalocyanines (Pigmosol® Green, Hostaphine® Green) or Solar Yellow BG 300 (Sandoz). The compositions are produced by mixing. Optionally, the product obtained for separating foreign particles and / or agglomerates can be decanted or filtered. The compositions have a viscosity greater than 100 mPas as measured at 20 ° C in a Brookfield viscometer.

9 Examples of embodiments of the invention

To determine the bleaching effect, the soiled fabric was treated with various chlorine bleaching liquors. The yellowing of the fabric was determined photometric, with the starting value of the soiled fabric serving as a standard (100%). The measurements were carried out in a bath containing metal ions of 300 ppb Fe and 100 ppb Mn; the water hardness was 1000 ppm CaCl ₂ , the bicarbonate content was 0.013 wt. The ratio of bath (fabric: water) was 1:50, the treatment time was 30 minutes at 40 ° C. The results are summarized in Table 1, the amount data being understood as% by weight. Examples 1-8 are according to the invention, examples V1 and V2 are for comparison.

Table 1

Bleaching effect

composition 1 2 3 4 5 6 7 8 V1 V2 sodium hypochlorite 5.0 sodium hydroxide 0.5 2-etylhexylfosfonát 0.1 0.1 0.1 0.1 - - - - - 0.2 sodium phosphite - - - - 0.1 - - - - - calcium phosphite - - - - - 0.1 - - - - nitrilotris (methylene) - - - - - - 0.1 0.1 - - polyacrylate * 0.1 sodium silicate ** - 0.1 - 0.1 0.1 0.1 0.1 0.1 0.2 - sodium carbonate - - 0.1 0.1 - - - 0.1 - - yellowing [% rel.] 85 85 85 83 88 89 84 83 101 92

*) polyacrylic acid, approximately 15,000 dalton ”) modulus 2.0 α-ζββο

Claims (12)

PATENT CLAIMS Use of mixtures of electrolytes containing (a) phosphonates; and (b) at least one other electrolyte salt selected from the group consisting of polyacrylates, silicates, carbonates and citrates as sequestering agents in the manufacture of aqueous bleaching compositions. Use according to claim 1, characterized in that the inorganic phosphonates have the formula I, HP (O) (OM ¹ ) ₂ (I) wherein M is an alkali metal, an alkaline earth metal, aluminum or zinc. Use according to claim 1 or 2, characterized in that the organic phosphonates have the formula II, R ¹ P (O) (OR ² ) ₂ (II) wherein R ¹ and R ² independently of one another are hydrogen or a linear or branched hydrocarbon radical having 1 to 22 carbon atoms, optionally containing functional groups, provided that R ¹ and R ² is not simultaneously hydrogen. I, Use according to claims 1 to 3, characterized in that nitrilotris (methylene phosphonate) or nitrilotris (ethylene phosphonate) are used as phosphonates. Use according to claims 1 to 4, characterized in that the polyacrylate salts of electrolytes are homo- or copolymers of acrylic acid, methacrylic acid and their esters with lower linear or branched alcohols having 1 to 8 carbon atoms. -11 Use according to claim 5, characterized in that the polyacrylates have an average molecular weight of from 300 to 5,000,000 daltons. Use according to claims 1 to 6, characterized in that the electrolyte salts are sodium silicate, potassium silicate, sodium carbonate, potassium carbonate, sodium citrate, potassium citrate, magnesium citrate and mixtures thereof. Use according to claims 1 to 7, characterized in that the phosphonates and electrolyte salts are used in a weight ratio of 95: 5 to 5:95. Use according to claims 1 to 8, characterized in that the electrolyte mixtures are used in an amount of 0.01 to 5% by weight. based on an aqueous bleaching composition. Use according to claims 1 to 9, characterized in that the electrolyte mixtures are used in a hypochlorite bleaching composition. Use according to Claims 1 to 10, 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 alkenyloligoglycosides and / or fatty acid salts. Use according to claims 1 to 11, characterized in that the electrolyte mixtures are used together with chlorine-stable fragrances.