Highly-concentrated detergent composition having improved storage stability

Abstract

The invention relates to a detergent composition comprising 20 wt.% or more surfactants and less than 55 wt.% water, each based on the total mass of the detergent composition, characterised in that the detergent composition comprises at least one aminopolycarboxylic acid having three or four carboxyl groups, or the salt thereof. The invention also relates to the use of an aminopolycarboxylic acid having three or four carboxyl groups, or the salt thereof, as a component of a detergent composition in order to prevent the occurrence of sediment in the detergent composition.

Description

[0001] Highly concentrated detergent composition with improved storage stability

[0002] field of technology

[0003] The invention relates to highly concentrated detergent compositions with improved storage stability, in which no insoluble precipitate occurs even after storage for several weeks.

[0004] Current state of the art

[0005] Liquid textile detergents typically contain complexing agents to bind cations, particularly calcium and magnesium ions, in the wash liquor. By binding these cations, complexing agents help maintain or increase the activity of detergent substances, especially anionic surfactants.

[0006] One problem with the use of complexing agents is the formation of poorly soluble complexes that remain as precipitates on the laundry or in the washing machine.

[0007] Modern textile detergents usually contain phosphonates as complexing agents, such as 1-hydroxyethene-1,1-diphosphonic acid (HEDP) or diethylenetriaminepentakis(methylenephosphonic acid) (DTPMP).

[0008] However, it has been shown that in highly concentrated detergent compositions, irreversible turbidity occurs after several weeks of storage, which is due to the formation of an insoluble precipitate. This turbidity occurs particularly in liquid textile detergents that contain phosphonates as complexing agents. This means that the detergent composition has a limited storage stability. Technical task

[0009] The object of the present invention is to improve the storage stability of liquid, highly concentrated detergents. The detergents should exhibit no turbidity, especially no turbidity due to calcium-containing precipitates, even after several weeks of storage. The detergents should contain only a small amount of water and at least one complexing agent.

[0010] Description of the invention

[0011] Surprisingly, it was found that the occurrence of precipitation in liquid, highly concentrated detergents can be prevented by using aminopolycarboxylic acids with three or four carboxyl groups as complexing agents, in particular by using L-glutamic acid / V, / \ / -diacetic acid (GLDA), instead of phosphorus-containing complexing agents. The aminopolycarboxylic acids serve as complexing agents.

[0012] One aspect of the invention therefore relates to a detergent composition comprising

[0013] 20% by weight or more of surfactants, and less than 55% by weight of water, each based on the total mass of the detergent composition, characterized in that the detergent composition comprises at least one aminopolycarboxylic acid having three or four carboxy groups or a salt thereof.

[0014] Preferably, the detergent composition comprises at least one aminopolycarboxylic acid selected from the group L-glutamic acid-N,N-diacetic acid (GLDA), methylglycinediacetic acid (MGDA), ß-alaninediacetic acid (ß-ADA), ethylenediaminetetraacetic acid (EDTA), hydroxyethylethylenediaminetriacetic acid (HEDTA), iminodisuccinate (IDS), or their salts.

[0015] The detergent composition preferably comprises L-glutamic acid-N,N-diacetic acid (GLDA) or a salt thereof. The amount of aminopolycarboxylic acids having three or four carboxyl groups is preferably 0.1% to 5% by weight, based on the total mass of the detergent composition.

[0016] Preferably, the detergent composition comprises less than 0.1 wt.% of 1-hydroxyethene-1,1-diphosphonic acid (HEDP) and diethylenetriaminepentakis(methylenephosphonic acid) (DTPMP), based on the total mass of the detergent composition.

[0017] Preferably, the detergent composition comprises

[0018] 12 wt% to 37 wt% anionic surfactants and

[0019] 8% to 15% by weight of non-ionic surfactants, each based on the total mass of the detergent composition.

[0020] Preferably, the detergent composition comprises an alkylbenzenesulfonic acid, an alkyl ether sulfate, a fatty acid and a nonionic surfactant.

[0021] Preferably, the detergent composition comprises 25% by weight or less of water, based on the total mass of the detergent composition.

[0022] Preferably, the detergent composition comprises monoethanolamine.

[0023] A further aspect of the invention relates to the use of an aminopolycarboxylic acid having three or four carboxy groups or its salt as a component of a detergent composition in order to prevent the occurrence of precipitation in the detergent composition.

[0024] Advantageous effects of the invention

[0025] The inventive use of an aminocarboxylic acid with three or four carboxyl groups can prevent the occurrence of precipitation in a detergent composition. This applies particularly to highly concentrated detergent compositions with a low water content and a medium or high surfactant concentration. Thus, detergent compositions with improved storage stability can be provided, in which no clouding is detectable even after several weeks of storage. The detergent compositions also exhibit excellent cleaning performance due to the combination of surfactants and aminocarboxylic acids.

[0026] Description of the embodiments

[0027] Embodiments of the present invention will be described in detail below. However, the present invention is not limited to the following embodiments.

[0028] One aspect of the invention relates to a detergent composition which can be used as a detergent.

[0029] A detergent is used to clean laundry. For the purposes of the invention, laundry items include, for example, hard surfaces such as stone floors, metal surfaces, glass or wooden surfaces, dishes, or products made of fiber material. In the broadest sense, the laundry items can also include body surfaces, such as the hands. The detergent can be, for example, a floor cleaner, a toilet cleaner, a dishwashing detergent, a fabric detergent, or a handwashing detergent.

[0030] In one embodiment, the detergent serves as a dishwashing detergent for cleaning all types of dishes and cutlery made of stainless steel, porcelain, glass or plastic.

[0031] In a preferred embodiment, the detergent is a textile detergent. A textile detergent is used for cleaning all types of woven, knitted, or warp-knitted textiles, as well as furs. In particular, the detergent can be used for cleaning laundry made of natural and / or synthetic fibers, for example, cotton, wool, linen, polyamide, polyester, polyacrylonitrile, or blends thereof. For example, the detergent is used as a textile detergent for cleaning laundry, for example, clothing, towels, bed linen, blankets, and curtains.

[0032] Cleaning refers to the removal of soiling from the laundry. This soiling can include, in particular, solid pigmented soiling, such as dust, soot, and metal abrasion; greasy and oily soiling, such as skin grease, cooking fat, and lubricating oil; colored soiling, such as fruit or plant juice and blood; and water-soluble soiling, such as urea, sugar, and salt.

[0033] The detergent is particularly suitable for being diluted with water to form a wash bath, which can be brought into contact with the laundry to be cleaned in order to loosen and wash away soiling.

[0034] The detergent can be used for both manual and machine washing. The detergent is particularly suitable as a general-purpose detergent for all washing processes and temperatures. It can also be used as a laundry aid together with another general-purpose detergent to extend and / or enhance its effectiveness. It can also be used before or after treatment with another detergent, for example, to remove soiling before a main wash cycle or to impart further desirable properties to the laundry after a main wash cycle, such as shine, pleasant smell, pleasant feel, crease resistance, or low static charge.

[0035] An essential feature of the detergent composition according to the invention is that the detergent composition comprises at least one aminopolycarboxylic acid with three or four carboxyl groups or a salt thereof. The aminopolycarboxylic acid serves as a complexing agent. Complexing agents are compounds that bind metal ions, in particular alkaline earth metal ions such as magnesium or calcium ions. For the purposes of the invention, an aminopolycarboxylic acid refers to an organic compound comprising at least one amino group and several carboxyl groups. According to the invention, the aminopolycarboxylic acids should have three or four carboxyl groups.

[0036] It has been found that in highly concentrated, liquid detergent compositions containing at least one aminopolycarboxylic acid with three or four carboxy groups as a complexing agent, no turbidity occurs even after storage for several weeks, unlike in detergent compositions containing phosphates or phosphonates as complexing agents.

[0037] Depending on the pH value of the detergent composition, the aminopolycarboxylic acids can be present in profaned form or in deprotonated form as dissolved salt.

[0038] Mixtures of different aminopolycarboxylic acids can also be used.

[0039] Suitable aminopolycarboxylic acids are, for example, L-glutamic acid-N,N-diacetic acid (GLDA), methylglycinediacetic acid (MGDA), ß-alaninediacetic acid (ß-ADA), ethylenediaminetetraacetic acid (EDTA), hydroxyethylethylenediaminetriacetic acid (HEDTA), iminodisuccinate (IDS), or their salts.

[0040] L-glutamic acid-N,N-diacetic acid (GLDA) has proven to be a particularly suitable aminopolycarboxylic acid.

[0041] The total amount of aminopolycarboxylic acid having three or four carboxyl groups in the detergent composition is preferably 0.1 wt.% to 5 wt.%, preferably 0.2 wt.% to 2.5 wt.%, more preferably 0.4 wt.% to 1.2 wt.%, most preferably 0.5 wt.% to 0.8 wt.%, based on the total mass of the detergent composition. Unless otherwise stated, these amounts refer to the sodium salt of the respective aminopolycarboxylic acid.

[0042] In a preferred embodiment, the detergent composition contains 0.1 wt% to 5 wt%, preferably 0.2 wt% to 2.5 wt%, more preferably 0.4 wt% to 1.2 wt%, most preferably 0.5 wt% to 0.8 wt% of L-glutamic acid-N,N-diacetic acid (GLDA), based on the mass of the sodium salt and the total mass of the detergent composition.

[0043] By using aminopolycarboxylic acid, the addition of phosphates and phosphonates as complexing agents can be eliminated. In particular, the use of 1-hydroxyethene-1,1-diphosphonic acid (HEDP) and diethylenetriaminepentakis(methylenephosphonic acid) (DTPMP) can be avoided.

[0044] In one embodiment, the detergent composition contains less than 0.1 wt.%, preferably less than 0.01 wt.%, most preferably less than 0.01 wt.% of 1-hydroxyethene-1,1-diphosphonic acid (HEDP) and diethylenetriaminepentakis(methylenephosphonic acid) (DTPMP), based on the mass of the respective sodium salt and the total mass of the detergent composition.

[0045] In one embodiment, the detergent composition contains less than 0.1 wt.%, preferably less than 0.01 wt.%, most preferably less than 0.01 wt.% of diphosphate, triphosphate, 1-hydroxyethene-1,1-diphosphonic acid (HEDP), amino-tri(methylenephosphonic acid) (ATP) and diethylenetriaminepentakis(methylenephosphonic acid) (DTPMP), based on the mass of the respective sodium salt and the total mass of the detergent composition.

[0046] In a particularly preferred embodiment, the detergent composition contains less than 0.1% by weight, preferably less than 0.01% by weight, most preferably less than 0.01% by weight of phosphates and phosphonates, based on the mass of the respective sodium salt and the total mass of the detergent composition.

[0047] In addition to the above-mentioned aminopolycarboxylic acids, the detergent composition may also contain other polycarboxylic acids, such as citric acid. In this context, other polycarboxylic acids refer to all polycarboxylic acids except aminopolycarboxylic acids. The amount of other polycarboxylic acids is preferably limited to 5% by weight or less, based on the total mass of the detergent composition.

[0048] The detergent composition contains at least one surfactant as a washing-active substance. The surfactant allows for effective removal of soils from the laundry to be cleaned.

[0049] The total amount of surfactants in the detergent composition is at least 20 wt.%, based on the total mass of the detergent composition. Preferably, the total amount of surfactants is 20 wt.% to 60 wt.%, particularly preferably 22 wt.% to 55 wt.%, most preferably 25 wt.% to 50 wt.%, in each case based on the total mass of the detergent composition.

[0050] The surfactant can be selected, in particular, from the group of anionic, nonionic, cationic, and amphoteric surfactants. The detergent composition can comprise a single surfactant or a mixture of different surfactants.

[0051] The detergent composition preferably comprises at least one anionic or nonionic surfactant. The detergent composition particularly preferably comprises both at least one anionic and at least one nonionic surfactant.

[0052] Anionic surfactants include, in particular, soaps, alkylbenzenesulfonates, alkanesulfonates, a-olefinsulfonates, a-sulfofatty acid esters, alkyl sulfates, alkenyl sulfates, alkyl ether sulfates, ether carboxylic acids and carboxylated alkylpolyglycosides.

[0053] The total amount of anionic surfactants is preferably 12 wt.% to 50 wt.%, particularly preferably 12 wt.% to 37 wt.%, most preferably 15 wt.% to 35 wt.%, in each case based on the total mass of the detergent composition. Soap refers to the salt of a fatty acid. The fatty acid can be linear or branched, saturated or unsaturated. Preferably, a linear saturated or unsaturated fatty acid is used. It is particularly preferred to use a linear saturated fatty acid.

[0054] The fatty acid preferably comprises at least 6 carbon atoms, more preferably at least 8 carbon atoms, most preferably at least 10 carbon atoms. The fatty acid particularly preferably comprises 6 to 32 carbon atoms, particularly preferably 8 to 28 carbon atoms, further preferably 10 to 18 carbon atoms, most preferably 12 to 18 carbon atoms. Preferred fatty acids are selected from the group consisting of caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, and mixtures thereof. Lauric acid, myristic acid, palmitic acid, and stearic acid are particularly suitable.

[0055] Soaps exhibit particularly good properties in detergent compositions. The detergent composition therefore preferably comprises soaps in an amount of 1 wt.% to 20 wt.%, particularly preferably 1 wt.% to 10 wt.%, most preferably 1 wt.% to 5 wt.%, in each case based on the total mass of the detergent composition.

[0056] Sulfuric acid semiesters of saturated or unsaturated fatty alcohols with 12 to 18 carbon atoms are preferably used as alkyl or alkenyl sulfates. Alkyl or alkenyl sulfates with 12 to 16 carbon atoms are preferred.

[0057] The alkyl ether sulfates used are preferably the sulfuric acid half esters of alkoxylated fatty alcohols. These are also referred to as fatty alcohol ether sulfates. These are preferably ethoxylated or propoxylated fatty alcohols. The fatty alcohols preferably comprise 6 to 22 carbon atoms, particularly preferably 10 to 20 carbon atoms, most preferably 12 to 18 carbon atoms. The fatty alcohols are preferably alkoxylated with 1 to 20, particularly preferably 1 to 10, most preferably 2 to 8 repeating units. The alkyl ether sulfates particularly preferably have the following structural formula:

[0058] Ri-O-(R2-O)n-SO3-X +, where Ri represents a linear or branched, saturated or unsaturated alkyl radical having 6 to 22 carbon atoms, particularly preferably 10 to 20 carbon atoms, most preferably 12 to 18 carbon atoms; R2 represents an alkenyl radical having 2 to 4 carbon atoms, particularly preferably 2 or 3 carbon atoms; n represents a number from 1 to 20, particularly preferably 1 to 10, most preferably 2 to 8; and X + for a cation, preferably an alkali metal cation, particularly preferably for K + or Na + stands.

[0059] The detergent composition preferably comprises alkyl ether sulfates in an amount of 1 wt% to 20 wt%, particularly preferably 2 wt% to 15 wt%, most preferably 5 wt% to 10 wt%, in each case based on the total mass of the detergent composition.

[0060] Compounds with the following structural formula are preferably used as alkylbenzenesulfonates:

[0061] Ri-Ph-SO X + , where Ri represents a linear or branched, saturated or unsaturated alkyl radical having 6 to 22 carbon atoms, particularly preferably 10 to 20 carbon atoms, most preferably 12 to 18 carbon atoms; Ph represents a phenyl radical; and X + for a cation, preferably an alkali metal cation, particularly preferably for K + or Na + stands.

[0062] A particularly preferred class of alkylbenzenesulfonates has the following structural formula:

[0063] R2R3CH-Ph-SO3-X +, where R2 represents a linear or branched, saturated or unsaturated alkyl radical having 6 to 22 carbon atoms, particularly preferably 8 to 20 carbon atoms, most preferably 12 to 18 carbon atoms; R3 represents a linear or branched, saturated or unsaturated alkyl radical having 1 to 10 carbon atoms, particularly preferably 1 to 5 carbon atoms, most preferably 1 to 3 carbon atoms; Ph represents a phenyl radical; and X + for a cation, preferably H + or an alkali metal cation, particularly preferably K + or Na + Preferably, in this embodiment, the radicals R2 and R3 comprise no more than 21 carbon atoms in total. Particularly preferably, R2 and R3 are linear alkyl radicals.

[0064] Alkylbenzenesulfonates exhibit particularly good properties in detergent compositions. The detergent composition therefore preferably comprises alkylbenzenesulfonates in an amount of 10 wt.% to 40 wt.%, particularly preferably 10 wt.% to 30 wt.%, and most preferably 10 wt.% to 25 wt.%, based in each case on the total mass of the detergent composition.

[0065] Non-ionic surfactants are in particular alkoxylated fatty alcohols, such as fatty alcohol ethoxylates or propoxylates, alkoxylated fatty amines, alkoxylated alkanolamines, fatty acid amides, alkoxylated fatty acid amides, polyhydroxy fatty acid amides, alkylphenol polyglycol ethers, amine oxides, alkyl glucosides, alkyl polyglucosides and alkoxylated alkylphenols.

[0066] The total amount of nonionic surfactants is preferably 6 wt% to 20 wt%, more preferably 8 wt% to 15 wt%, most preferably 8 wt% to 12 wt%, in each case based on the total mass of the detergent composition.

[0067] As alkoxylated fatty alcohols, compounds with the following structural formula are preferably used:

[0068] Ri-O-(R2-O) n-H, where R 1 represents a linear or branched, saturated or unsaturated alkyl radical having 6 to 22 carbon atoms, particularly preferably 10 to 20 carbon atoms, most preferably 12 to 18 carbon atoms; R 2 represents an alkenyl radical having 2 to 4 carbon atoms, particularly preferably 2 or 3 carbon atoms; and n represents a number from 1 to 20, particularly preferably 3 to 15, most preferably 5 to 10. Alkoxylated fatty alcohols have particularly good properties in the detergent composition. The detergent composition therefore preferably comprises alkoxylated fatty alcohols in an amount of 6% to 20% by weight, particularly preferably 8% to 15% by weight, most preferably 8% to 12% by weight, in each case based on the total mass of the detergent composition.

[0069] As alkoxylated alkanolamines, compounds with the following structural formula are preferably used:

[0070] (HO-R 1-O-(R 2 -O)nR 3 )3-N where the radicals R 1 , R 2 , R 3 each independently represents alkenyl radicals having 2 to 4 carbon atoms and n represents a number from 5 to 30, particularly preferably 10 to 25, most preferably 15 to 20. A particularly preferred alkoxylated amine is propoxylated and ethoxylated triethanolamine.

[0071] Amphoteric surfactants include, in particular, betaines, sulfobetaines and imidazoline derivatives such as cocoamphodiacetate.

[0072] Cationic surfactants are particularly fatty amine salts and quaternary ammonium compounds.

[0073] In one embodiment, the detergent composition does not comprise amphoteric or cationic surfactants.

[0074] In a particularly preferred embodiment, the detergent composition does not comprise cationic surfactants.

[0075] In a preferred embodiment, the detergent composition comprises an alkylbenzenesulfonic acid, an alkyl ether sulfate, a fatty acid, and a nonionic surfactant. In a further preferred embodiment, the detergent composition comprises an alkylbenzenesulfonic acid, an alkyl ether sulfate, a fatty acid, and an alkoxylated fatty alcohol. The detergent composition also comprises water in an amount of less than 55% by weight, based on the total mass of the detergent composition. The detergent composition is therefore a highly concentrated composition. This has the advantage that the total volume of the detergent composition is small, which minimizes the space required for transport and storage of the detergent composition.

[0076] The detergent composition preferably comprises less than 40 wt%, preferably 25 wt% or less, more preferably 20 wt% or less, more preferably 18 wt% or less, most preferably 15 wt% or less of water, in each case based on the total mass of the detergent composition. In one embodiment, the detergent composition comprises 1 wt% to less than 55 wt%, preferably 1 wt% to less than 40 wt%, more preferably 1.5 wt% to 25 wt%, more preferably 2 wt% to 20 wt%, more preferably 4 wt% to 18 wt%, most preferably 5 wt% to 15 wt% of water, in each case based on the total mass of the detergent composition.

[0077] The detergent composition may further comprise at least one other solvent besides water. Other solvents include, in particular, mono- or polyhydric alcohols, alkanolamines, and glycol ethers.

[0078] The amount of the further solvent is preferably 5 wt% to 40 wt%, preferably 5 wt% to 20 wt%, most preferably 5 wt% to 15 wt%, in each case based on the total mass of the detergent composition.

[0079] The detergent composition is preferably liquid. The total amount of water and other solvents is therefore preferably 5% by weight or more, particularly preferably 10% by weight or more, most preferably 15% by weight or more, in each case based on the total mass of the detergent composition. In a preferred embodiment, the detergent composition comprises at least one polyhydric alcohol (polyol). Suitable polyols are, in particular, those alcohols having two or more OH groups and 2 to 8 carbon atoms. Polyols having 2 or 3 OH groups and 3 to 6 carbon atoms are particularly suitable. Suitable polyols include, in particular, propanediol, in particular 1,2-propanediol; butanediol, in particular 1,2-butanediol, 1,3-butanediol, and 1,4-butanediol; glycerol, or mixtures thereof.

[0080] The total amount of polyols is preferably 5 wt% to 40 wt%, preferably 5 wt% to 20 wt%, most preferably 5 wt% to 15 wt%, in each case based on the total mass of the detergent composition.

[0081] The total amount of polyols having two or more OH groups and 2 to 8 carbon atoms is preferably 5 wt% to 40 wt%, preferably 5 wt% to 20 wt%, most preferably 5 wt% to 15 wt%, in each case based on the total mass of the detergent composition.

[0082] In a preferred embodiment, the detergent composition comprises propanediol in an amount of 5 wt% to 40 wt%, preferably 5 wt% to 20 wt%, most preferably 5 wt% to 15 wt%, in each case based on the total mass of the detergent composition.

[0083] The detergent composition may further comprise one or more adjuvants. These include, in particular, bleaching agents, such as hypochlorite bleach, perborates, percarbonates, perphosphates, and percarbamides; whiteners; enzyme stabilizers, foam inhibitors, corrosion inhibitors, dyes, fragrances, and preservatives.

[0084] The auxiliaries also include, in particular, polymers used as activity enhancers, such as polyethyleneimines, alkoxylated polyethyleneimines, vinylimidazole / vinylpyrrolidone copolymers, and propylene glycol terephthalates. The detergent composition preferably contains 2 to 20 wt.%, more preferably 5 to 15 wt.%, most preferably 6 to 10 wt.% of polymers selected from the group of polyethyleneimines, alkoxylated polyethyleneimines, vinylimidazole / vinylpyrrolidone copolymers, and propylene glycol terephthalates, each based on the total mass of the detergent composition.

[0085] The detergent composition may, in particular, also contain one or more enzymes. For example, the detergent composition may contain proteases, cellulases, hexosamidases (especially dispersins), amylases, lipases, tannases, mannanases, and polyesterases. In particular, the detergent composition may also contain calcium-containing enzymes, in which calcium is either bound as a cofactor or included as a component of the enzyme preparation, without the risk of forming a precipitate of an insoluble calcium salt.

[0086] The detergent composition preferably has a pH of 7 to 12, more preferably 7.5 to 9, most preferably 7.5 to 8.5. The pH is determined at 20°C. If the detergent composition has too low a water content to reliably determine the pH, the composition is diluted with water for the measurement. The pH is preferably adjusted by adding a suitable base (pH adjuster). The detergent composition preferably comprises a base selected from the group consisting of amines, alkali metal carbonate, and alkali metal hydroxide, more preferably selected from monoethanolamine, sodium carbonate, and sodium hydroxide.

[0087] The use of monoethanolamine instead of other pH adjusters is particularly preferred in highly concentrated detergent compositions. However, highly concentrated compositions containing a combination of monoethanolamine and phosphonates have been shown to be unstable. This instability is not observed in compositions containing monoethanolamine and the aminopolycarboxylic acids described above. The detergent composition therefore preferably comprises monoethanolamine, preferably in an amount of 1 wt.% to 10 wt.%, particularly preferably 4 wt.% to 8 wt.%, based on the total mass of the detergent composition.

[0088] A further aspect of the invention relates to the use of an above-described aminopolycarboxylic acid having three or four carboxy groups or a salt thereof as a component of a detergent composition in order to prevent the occurrence of precipitation in the detergent composition.

[0089] The aminopolycarboxylic acids are preferably used in the amounts described above. The detergent composition preferably has the composition described above.

[0090] In particular, the use serves to prevent the occurrence of precipitation in the detergent composition at a temperature of up to 40 °C and / or a storage period of up to eight weeks.

[0091] Examples

[0092] The present invention will be described in more detail below using examples. However, the present invention is not limited to the following examples.

[0093] Various detergent compositions were prepared and tested for their storage stability. Each detergent composition was prepared using the ingredients listed in Table 1. The detergent compositions were stored at 40 °C and tested for the occurrence of precipitate over a period of eight weeks. Table 1: Detergent compositions (data in wt.%)

[0094] 2 L-Glutamic acid-N,N-diacetic acid, sodium salt

[0095] 3 pH adjusters except monoethanolamine, citric acid, dyes, fragrances, enzymes, etc.

[0096] In comparative composition 1, which contained the phosphonate HEDP as a complexing agent, a significant precipitate and clouding of the detergent composition occurred within the observation period. In composition 2 according to the invention, which contained the aminopolycarboxylic acid GLDA, no precipitate was observed over the same period.

[0097] The same result was also observed in compositions 3 and 4, each containing a lower amount of surfactants. Comparative composition 3 with HEDP showed significant precipitation within the observation period, while no precipitation occurred in inventive composition 4 with GLDA.

Claims

Patent claims 1. Detergent composition comprising 20% by weight or more of surfactants, and less than 55% by weight of water, each based on the total mass of the detergent composition, characterized in that the detergent composition comprises at least one aminopolycarboxylic acid having three or four carboxy groups or a salt thereof.

2. Detergent composition according to claim 1, wherein the detergent composition comprises at least one aminopolycarboxylic acid selected from the group L-glutamic acid-N,N-diacetic acid (GLDA), methylglycinediacetic acid (MGDA), ß-alaninediacetic acid (ß-ADA), ethylenediaminetetraacetic acid (EDTA), hydroxyethyl ethylenediaminetriacetic acid (HEDTA), iminodisuccinate (IDS), or salts thereof.

3. A detergent composition according to claim 1 or claim 2, wherein the detergent composition comprises L-glutamic acid-N,N-diacetic acid (GLDA) or a salt thereof.

4. Detergent composition according to one of claims 1 to 3, wherein the amount of aminopolycarboxylic acids having three or four carboxy groups is 0.1 wt% to 5 wt%, based on the total mass of the detergent composition.

5. A detergent composition according to any one of claims 1 to 4, wherein the detergent composition comprises less than 0.1 wt.% of 1-hydroxyethene-1,1-diphosphonic acid (HEDP) and diethylenetriaminepentakis(methylenephosphonic acid) (DTPMP), based on the total mass of the detergent composition.

6. Detergent composition according to any one of claims 1 to 5, wherein the detergent composition 12 wt% to 37 wt% anionic surfactants and 8 wt.% to 15 wt.% non-ionic surfactants, each based on the total mass of the detergent composition.

7. A detergent composition according to any one of claims 1 to 6, wherein the detergent composition comprises an alkylbenzenesulfonic acid, an alkyl ether sulfate, a fatty acid and a nonionic surfactant.

8. A detergent composition according to any one of claims 1 to 7, wherein the detergent composition comprises 25% by weight or less of water, based on the total mass of the detergent composition.

9. A detergent composition according to any one of claims 1 to 8, wherein the detergent composition comprises monoethanolamine.

10. Use of an aminopolycarboxylic acid having three or four carboxy groups or a salt thereof as a component of a detergent composition to prevent the occurrence of precipitation in the detergent composition.