Dishwasher cleaning composition

Abstract

The invention relates to a dishwasher-cleaning composition comprising between 10 wt.% and 35 wt.% of a mixture comprising a tribasic acid or salt thereof, preferably citric acid or a citric acid salt, and an acid or an acid salt; wherein said acid or acid salt comprises a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton. The invention further relates to a product comprising a container comprising a dispensing means, wherein the container comprises such a dishwasher cleaning composition.

Description

[0001] DISHWASHER CLEANING COMPOSITION

[0002] Technical Field of the Invention

[0003] The present invention relates to a dishwasher cleaning composition, and a product comprising a container comprising the dishwasher cleaning composition.

[0004] Background to the Invention

[0005] Automatic dishwashing machines or automatic dishwashers are convenient and energy efficient, but their performance may be reduced due to limescale and fat and grease formation during use. Limescale is formed from metal ions (e.g., calcium and magnesium) being deposited from water to the surface of the dishwasher as carbonate crystals; this can be particularly problematic in areas with hard water. Fat and grease formation is caused by deposit from soiled dishes in the dishwasher. Dishwasher cleaners provide a convenient way for dishwashing machine owners to effectively clean their dishwashers and remove limescale or prevent the build-up of limescale between cleanings.

[0006] Dishwashers can be expensive to purchase and to repair. Limescale build up can cause long term damage to components within the dishwasher which may eventually lead to machine breakdown or requirements for expensive maintenance. It would therefore be advantageous to provide a dishwasher cleaning composition which may suitably clean the dishwasher, and which may reduce the rate of limescale formation and / or reduce the amount of limescale within a dishwashing machine.

[0007] Fluctuations in raw material costs for typical components used in dishwasher cleaning compositions has led to the requirement to provide alternative formulations with desirable limescale removal and cleaning properties. It would therefore be advantageous to provide a cost-effective dishwasher cleaning composition which may suitably clean the dishwasher, and which may reduce the rate of limescale formation and / or reduce the amount of limescale within a dishwashing machine.

[0008] Dishwasher cleaning compositions typically comprise acids to interact with the salts found in limescale and / or hard water. Some acids may negatively impact the dishwasher by corroding or tarnishing elements of the dishwasher. It would therefore be advantageous to provide a dishwasher cleaning composition comprising a mixture of components which may suitably clean the dishwasher, reduce the rate of limescale formation and / or reduce the amount of limescale within a dishwashing machine and which may also not negatively damage the dishwasher or elements of the dishwasher.

[0009] It is an aim of embodiments of the invention to overcome one or more problems of the prior art, whether expressly disclosed herein or not.

[0010] Summary of the Invention

[0011] According to a first aspect of the invention there is provided a dishwashercleaning composition comprising between 10 wt.% and 35 wt.% of a mixture comprising a tribasic acid or salt thereof, preferably citric acid or a citric acid salt, and an acid or an acid salt; wherein said acid or acid salt comprises a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton.

[0012] The dishwasher cleaning composition may comprise between 15 wt.% and 35 wt.%, 15 wt.% and 30 wt.% or preferably between 15 wt.% and 25 wt.% of the mixture.

[0013] The mixture may be advantageous because it may reduce the rate of limescale formation and / or reduce the amount of limescale within the dishwasher. The mixture may be advantageous because it may reduce the rate of limescale formation and / or reduce the amount of timescale within the dishwasher and may not negatively corrode or damage the dishwasher during a cleaning process.

[0014] A tribasic acid (otherwise known as a triprotic acid) is defined as an acid comprising three ionizable hydrogen atoms per molecule. A tribasic acid salt is defined as a tribasic acid wherein at least one acidic hydrogen is salted with at least one ion.

[0015] The tribasic acid may be phosphoric acid. The tribasic acid may not comprise nitrogen. In preferred embodiments the tribasic acid is citric acid. Citric acid may be advantageous because it may reduce the pH of the formulation. Citric acid may be advantageous because it may reduce the rate of limescale formation and / or reduce the amount of limescale within the dishwasher.

[0016] The tribasic acid or salt thereof may be citric acid or a citric acid salt. The citric acid salt be selected from the group consisting of sodium citrate, potassium citrate, potassium-sodium citrate and potassium-magnesium citrate or any combination thereof.

[0017] The mixture may comprise at least 15 wt.%, preferably at least 25 wt.%, and more preferably at least 35 wt.%, in particular at least 50 wt.%, tribasic acid or salt thereof wherein the wt.% is the percentage of the total weight of the mixture.

[0018] The mixture may comprise no more than 80 wt.%, 75 wt.%, 70 wt.%, 65 wt.%, 60 wt.% or 55 wt.% tribasic acid or salt thereof.

[0019] The mixture may comprise between 75 wt.% and 15 wt.%, 75 wt.% and 30 wt.%, 70 wt.% and 35 wt.%, 70 wt.% and 40 wt.%, 60 wt.% and 40 wt.% or between

[0020] 55 wt.% and 40 wt.% tribasic acid or salt thereof. The acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof may comprise 1 acidic proton. The acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof may comprise 2 acidic protons.

[0021] In one embodiment, said acid or acid salt comprises a total of 1 to 3 atoms selected from C, S or a combination thereof and 1 or 2 acidic protons.

[0022] The acid or acid salt may comprise one sulfur atom and no carbon atoms and at least 1 acidic proton. The acid or acid salt may comprise one sulfur atom and one carbon atom and at least 1 acidic proton. The acid or acid salt may comprise one sulfur atom and one carbon atom and at least 1 acidic proton. The acid or acid salt may comprise between 1 and 3 carbon atoms and no sulfur atoms and at least 1 acidic proton. The acid or acid salt may comprise 3 carbon atoms and no sulfur atoms and at least 1 acidic proton.

[0023] The acid or acid salt may comprise one sulfur atom and no carbon atoms and 1 acidic proton. The acid or acid salt may comprise one sulfur atom and no carbon atoms and 2 acidic protons. The acid or acid may comprise one sulfur atom and one carbon atom and 1 acidic proton. The acid or acid salt may comprise one sulfur atom and one carbon atom and 2 acidic protons. The acid or acid salt may comprise one sulfur atom and one carbon atom and 1 acidic proton. The acid or acid salt may comprise one sulfur atom and one carbon atom and 2 acidic protons. The acid or acid salt may comprise between 1 and 3 carbon atoms and no sulfur atoms and 1 acidic proton. The acid or acid salt may comprise between 1 and 3 carbon atoms and no sulfur atoms and 2 acidic protons. The acid or acid salt may comprise 3 carbon atoms and no sulfur atoms and 1 acidic proton. The acid or acid salt may comprise 3 carbon atoms and no sulfur atoms and 2 acidic protons.

[0024] This embodiment may be advantageous because the acid or acid salt compounds may comprise a smaller molecular weight and therefore may be highly soluble in the dishwasher machine cleaning composition. This embodiment may be advantageous because the acid or acid salt components may synergistically provide superior limescale removal performance or improved prevention of limescale formation.

[0025] In preferred embodiments the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton may be selected from the group consisting of lactic acid, sulfamic acid, methanesulfonic acid and sodium bisulfate and any combination thereof.

[0026] This embodiment may be advantageous because the combination of the tribasic acid or salt thereof and the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton may synergistically provide superior limescale removal performance or improved prevention of limescale formation.

[0027] In preferred embodiments the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton may be selected from the group consisting of lactic acid, sulfamic acid and methanesulfonic acid and any combination thereof and may not be sodium bisulfate.

[0028] In preferred embodiments the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton may be selected from the group consisting of sulfamic acid and methanesulfonic acid, sodium bisulfate and any combination thereof and may not be lactic acid.

[0029] The acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton may comprise a pKa of between -2 and 4. The acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton may comprise a pKa of between -2 and 3, -2 and 2, -2 and 1 or between -2 and 0.

[0030] This embodiment may be advantageous because the pKa of the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton may be lower than the tribasic acid or acid salt thereby allowing the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton to more easily interact with metal ions found in limescale or hard water and thereby improve limescale removal performance and / or reduce limescale formation.

[0031] The mixture may comprise at least 35 wt.% acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton wherein the wt.% is the percentage of the weight of the mixture. The mixture may comprise at least 40 wt.%, 42 wt.%, 44 wt.%, 46 wt.%, 48 wt.% or at least 50 wt.% acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton wherein the wt.% is the percentage of the weight of the mixture. The mixture may comprise no more than 80 wt.% acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton thereof. The mixture may comprise no more than 75 wt.%, 70 wt.%, 65 wt.%, 60 wt.% or 55 wt.% acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton. The mixture may comprise between 75 wt.% and 30 wt.% acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton. The mixture may comprise between 75 wt.% and 35 wt.%, 70 wt.% and 35 wt.%, 70 wt.% and 40 wt.%, 60 wt.% and 40 wt.% or between 55 wt.% and 40 wt.% acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton. Higher concentrations of the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton may result in the corrosion of parts within the dishwasher. This embodiment may therefore be advantageous because it may provide a mixture wherein the amount of the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton may be reduced compared to formulations comprising acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton only, thereby preventing the corrosion of parts within the machine and improving the limescale removal performance.

[0032] The dishwasher cleaning composition may comprise at least 1 wt.% of the tribasic acid or salt thereof wherein the wt.% is the percentage of the weight of the dishwasher cleaning composition. The dishwasher cleaning composition may comprise at least 2 wt.%, 5 wt.%, 7 wt.%, 8 wt.%, 9 wt.%, 10 wt.% 11 wt.%, 12 wt.%, 13 wt.%, 14 wt.% or at least 15 wt.% of the tribasic acid or salt thereof. The dishwasher cleaning composition may comprise no more than 30 wt.% of the tribasic acid or salt thereof wherein the wt.% is the percentage of the weight of the dishwasher cleaning composition. The dishwasher cleaning composition may comprise no more than 28 wt.%, 25 wt.%, 22 wt.%, 21 wt.%, 20 wt.%, 19 wt.% 18 wt.%, 17 wt.% or no more than 16 wt.% of the tribasic acid or salt thereof. The dishwasher cleaning composition may comprise between 1 wt.% and 30 wt.% of the tribasic acid or salt thereof wherein the wt.% is the percentage of the weight of the dishwasher cleaning composition. The dishwasher cleaning composition may comprise between 2 wt.% and 28 wt.%, 5 wt.% and 25 wt.%, 5 wt.% and 22 wt.%, 5 wt.% and 20 wt.%, 5 wt.% and 17.5 wt.%, 8 wt.% and 17.5 wt.%, 10 wt.% and 17.5 wt.% or between 10 wt.% and 15 wt.% of the tribasic acid or salt thereof wherein the wt.% is the percentage of the weight of the dishwasher cleaning composition. This embodiment may be advantageous because it may reduce the rate of limescale formation and / or reduce the amount of limescale within the dishwasher. The reduced amount of tribasic acid or salt thereof may be advantageous because it may provide a more cost-effective dishwasher cleaning composition compared to a formulation comprising a higher concentration of tribasic acid or salt thereof.

[0033] The dishwasher cleaning composition may comprise at least 2 wt.% of the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton wherein the wt.% is the percentage of the weight of the dishwasher cleaning composition. The dishwasher cleaning composition may comprise at least 3 wt.%, 4 wt.%, 5 wt.%, 7.5 wt.%, 10 wt.%, 12 wt.%, 14 wt.% or at least 15 wt.% of the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton. The dishwasher cleaning composition may comprise no more than 30 wt.% of the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton wherein the wt.% is the percentage of the weight of the dishwasher cleaning composition. The dishwasher cleaning composition may comprise no more than 28 wt.%, 25 wt.%, 22 wt.%, 21 wt.%, 20 wt.%, 19 wt.% 18 wt.%, 17 wt.% or no more than 16 wt.% of the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton. The dishwasher cleaning composition may comprise between 1 wt.% and 30 wt.% of the tri acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton wherein the wt.% is the percentage of the weight of the dishwasher cleaning composition. The dishwasher cleaning composition may comprise between 2 wt.% and 28 wt.%, 2 wt.% and 25 wt.%, 2 wt.% and 20 wt.%, 5 wt.% and 20 wt.%, 2 wt.% and 17.5 wt.% or preferably between 2 wt.% and 15 wt.%, 10 wt.% and 17.5 wt.% or between 10 wt.% and 15 wt.% of the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton wherein the wt.% is the percentage of the weight of the dishwasher cleaning composition. This embodiment may therefore be advantageous because it may provide a mixture wherein the amount of the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton may be reduced compared to formulations comprising the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton only, thereby preventing the corrosion of parts within the dishwasher and improving the limescale removal performance.

[0034] The ratio of the tribasic acid or salt thereof and the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton may be between 1:10 and 10:1. The ratio of the tribasic acid or salt thereof and the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton may be between 1 : 8 and 9: 1 , or 1 : 7 and 8:1, or 1:6 and 8:1, or 1:5 and 8: 1, or 1:4 and 8:1. The ratio of the tribasic acid or salt thereof and the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton may be between 1:3 and 7:1. This embodiment may be advantageous because the ratio of the amounts of tribasic acid or salt thereof and the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton may improve the limescale removal performance of the dishwasher cleaning composition.

[0035] The dishwasher cleaning composition may comprise a component selected from the group consisting of complexing agents, colouring agents, surfactants, solvents, fragrances, antioxidants, polymers, enzymes, anti-corrosion agents, UV filter, antifoaming agents, preservatives and polymers or any combination thereof.

[0036] The dishwasher cleaning composition may comprise at least one complexing agent. A complexing agent may also be known a sequestering agent. The complexing agent may be a phosphate, a phosphonate, a polycarboxylate, a zeolite or any combination thereof. The complexing agent may be selected from the group consisting of: 1-hydroxy ethylidene-l,l-diphosphonic acid (HEDP), methylglycine diacetic acid (MGDA) and tetrasodium glutamate diacetate (GLDA), ethylenediamine disuccinic acid (EDDS), ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), diethylenetriaminepentamethylene phosphonic acid (DTPM PA), nitrilotriacetic acid (NTA), aspartic acid diethoxysuccinic acid (AES), aspartic acid- N,N-diacetic acid (ASDA), ethylenediamine tetra methylene phosphonic acid (EDTMP), iminodifumaric (IDF), iminoditartaric acid (IDT), iminodimaleic acid

[0037] (IDMAL), iminodimalic acid (IDM), ethylene-diaminedifumaric acid (EDDF), ethylene-diaminedimalic acid (EDDM), ethylene- diamineditartaric acid (EDDT), ethylenediaminedimaleic acid and (EDDMAL), amino- tri(methylenephosphonic acid) (ATM) and any salt thereof or any combination thereof. In preferred embodiments the complexing agent may be selected from the group consisting of: 1 -hydroxy ethylidene- 1,1-diphosphonic acid (HEDP), methylglycine diacetic acid (MGDA) and tetrasodium glutamate diacetate (GLDA). The complexing agent may not be within the mixture. This embodiment may be advantageous because the complexing agent may complex with limescale ions such as calcium, magnesium and other heavy metal ions, to form larger molecules which may be filtered such that they are removed from the dishwasher during the dishwasher cleaning process.

[0038] The dishwasher cleaning composition may comprise no more than 5 wt.% complexing agent. The dishwasher cleaning composition may comprise no more than 4 wt.%, 3 wt.%, 2 wt.%, 1.5 wt.% or preferably no more than 1 wt.% complexing agent. The dishwasher cleaning composition may comprise no more than 0.8 wt.%, 0.6 wt.%, 0.5 wt.%, 0.4 wt.% or no more than 0.3 wt.% complexing agent.

[0039] The dishwasher cleaning composition may comprise at least one colouring agent. The dishwasher cleaning composition may comprise at least 2 or at least 3 colouring agents. The colouring agent may be a dye. A dye is defined as a colour additive which is at least partially soluble in water. The colouring agent may be an organic compound. The colouring agent may be an inorganic compound. The colouring agent may be a natural compound or preferably a synthetic compound. The colouring agent may be an acid dye. The colouring agent may comprise an azo, anthraquinone or triphenyl methane-based dye. The colouring agent may comprise an azine, a xanthane, a nitro, an indigoid, a quinoline or a carbolan dye. The dishwasher cleaning composition may comprise between 0.0001 wt.% and 0.01 wt.% colouring agent wherein the amount is the total amount of colouring agent. The dishwasher cleaning composition may comprise between 0.0001 wt.% and 0.005 wt.%, or 0.0001 wt.% and 0.004 wt.%, or 0.0001 wt.% and 0.003 wt.%, or between 0.0001 wt.% and 0.002 wt.% colouring agent.

[0040] The dishwasher cleaning composition may comprise at least one solvent. The solvent may be an aqueous solvent. The solvent may be an alcohol. The solvent may be an ether such as a glycol ether. The solvent may be water. The solvent may be poly glycol.

[0041] The dishwasher cleaning composition may comprise between 40 wt.% and 70 wt.% solvent. The dishwasher cleaning composition may comprise between 45 wt.% and 65 wt.%, 50 wt.% and 65 wt.% or between 55 wt.% and 62 wt.% solvent. The dishwasher cleaning composition may comprise between 40 wt.% and 70 wt.% water. The dishwasher cleaning composition may comprise between 45 wt.% and 65 wt.%, 50 wt.% and 65 wt.% or between 55 wt.% and 62 wt.% water.

[0042] The dishwasher cleaning composition may comprise at least one surfactant The surfactant may preferably be a non-ionic surfactant. The surfactant may preferably be selected from the group consisting of straight chain fatty alcohol alkoxylates, branched fatty alcohol alkoxylates, alkoxylated alcohols, preferably ethoxylated alcohols, propoxylated alcohols, ethoxylated / propoxylated alcohols, alkylphenol ethoxylates, fatty acid ethoxylates, ethoxylated amines, fatty acid amides, fatty acid esters of glycerol, sorbitol, sucrose, alkyl polyglucosides and amino acid-based surfactants or any combination thereof. In some embodiments the alkyl chain of the surfactant comprises between 8 and 18 carbon atoms, preferably between 8 and 16 carbon atoms, more preferably between 8 and 14 carbon atoms. In preferred embodiments the surfactant comprises a C12 to C14 ethoxylated alcohol. In alternative preferred embodiments the surfactant comprises a C9 to Cl 1 ethoxylated alcohol.

[0043] The dishwasher cleaning composition may comprise between 0.001 wt.% and 10 wt.% of at least one surfactant, based on the total weight of the dishwasher cleaning composition. The dishwasher cleaning composition may comprise between 0.005 wt.% and 10 wt.%, 0.01 wt.% and 7.5 wt.%, or preferably between 0.5 wt.% and 5 wt.% of at least one surfactant, based on the total weight of the dishwasher cleaning composition. This embodiment may be advantageous because it may improve the fat and grease removal performance of the dishwasher cleaning composition thereby preventing fat and grease build up within the dishwasher which could in turn lead to damage within the dishwasher, reduced performance or reduced efficiency.

[0044] The dishwasher cleaning composition may comprise at least one fragrance. The fragrance compound may comprise an ester, a terpene, an aromatic group or an amine or any combination thereof. The dishwasher cleaning composition may comprise between 0.005 wt.% and 2 wt.% of at least one fragrance. The dishwasher cleaning composition may comprise between 0.01 wt.% and 1.5 wt.%, 0.02 wt.% and 1 wt.%, 0.02 wt.% and 0.5 wt.%, 0.03 wt.% and 0.3 wt.%, 0.03 wt.% and 0.1 wt.% or between 0.03 wt.% and 0.05 wt.% of at least one fragrance based on the total weight of the dishwasher cleaning composition. The dishwasher cleaning composition may comprise at least one antioxidant. The antioxidant may be a phenol. The antioxidant may be selected from the group consisting of: benzotriazole (BTA), butylated hydroxy toluene (BHT), butylated hydroxyanisole (BHA) and glutathione and any combination thereof. The dishwasher cleaning composition may comprise between 0.005 wt.% and 2 wt.% of at least one antioxidant. The dishwasher cleaning composition may comprise between 0.01 wt.% and 2 wt.%, 0.02 wt.% and 2 wt.%, 0.05 wt.% and 2 wt.%, 0.05 wt.% and 1.5 wt.% or between 0.08 wt.% and 0.12 wt.% of at least one antioxidant based on the total weight of the dishwasher cleaning composition.

[0045] The mixture may be a homogeneous liquid. The mixture may comprise an aqueous solution. This may be advantageous because it may allow the mixture to efficiently come into contact with part or all of the dishwasher in use without the need for the mixture to dissolve first.

[0046] The dishwasher cleaning composition may be a liquid. The dishwasher cleaning composition may be a mono-, bi- or triphasic liquid. In embodiments wherein the dishwasher cleaning composition comprises at least two phases, each phase may comprise a different density, colour, volume, pH or any combination thereof.

[0047] In some embodiments the dishwasher cleaning composition comprises at least two phases wherein the mixture is within one phase. In some embodiments the dishwasher cleaning composition comprises at least two phases wherein the mixture and an aqueous solution are within one phase. In some embodiments the dishwasher cleaning composition comprises at least two phases wherein the mixture is within one phase and at least one other phase comprises a surfactant. In some embodiments the dishwasher cleaning composition comprises at least two phases wherein the acid mixture is within one phase and at least one other phase comprises a surfactant and preferably at least one dye.

[0048] The dishwasher cleaning composition may comprise a pH between 1 and 4. The dishwasher cleaning composition may comprise a pH between 1 and 3, 1 and 2.5, 1 and 2 or between 1 and 1.5.

[0049] According to a second aspect of the invention there is provided a dishwasher cleaning composition comprising between 10 wt.% and 35 wt.% of a mixture comprising a tribasic acid or salt thereof and lactic acid.

[0050] The statements of the dishwasher cleaning composition of the first aspect of the invention may apply to the second aspect of the invention.

[0051] According to a second aspect of the invention there is provided a product comprising a container comprising a dispensing means, wherein the container comprises a dishwasher cleaning composition according to the first or the second aspect of the invention.

[0052] In some embodiments the container comprises a central cavity wherein the dishwasher cleaning composition is located. In some embodiments the container comprises a central cavity which is not divided into portions and wherein the dishwasher cleaning composition is located in the central cavity. In some embodiments the container comprises a cavity wherein the cavity is divided into at least two portions wherein the dishwasher cleaning composition is located in each of the at least two portions. In some embodiments the container comprises a cavity divided into at least two portions wherein the dishwasher cleaning composition is a liquid comprising at least two phases and each phase is located in each of the at least two portions.

[0053] The volume of the dishwasher cleaning composition within the container may be between 50 mL and 1000 mL or between 50 mL and 500 mL The volume of the dishwasher cleaning composition within the container may be between 50 mL and 400 mL, 50 mL and 300 mL, 75 mL and 300 mL, 100 mL and 300 mL or between 150 mL and 250 mL or between 250 mL and 500 mL

[0054] Detailed Description of the Invention

[0055] 1

[0056] A first embodiment of a first aspect of the dishwasher cleaning composition of the invention is provided wherein the dishwasher cleaning composition comprises between 10 wt.% and 35 wt.%, preferably 15 wt.% to 20 wt.% of a mixture comprising a tribasic acid and an acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton wherein the tribasic acid is citric acid, and the acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton is sodium bisulfate.

[0057] The dishwasher cleaning composition further comprises a complexing agent, a fragrance, a non-ionic surfactant, a dye, a preservative and water. The complexing agent is HEDP. The non-ionic surfactant is a C9 to Cl l ethoxylated alcohol.

[0058] The dishwasher cleaning composition is a bi-phasic liquid wherein the first phase is denser than the second phase. The first phase comprises the mixture comprising citric acid and sodium bisulfate and the second phase comprises the surfactant and the dye. Example formulations A to I of the first embodiment of the invention were provided and the formulations are disclosed in table 1 below.

[0059] Example 2

[0060] A first embodiment of a second aspect of the product of the invention is provided wherein the product comprises a container comprising a dispensing means, wherein the container comprises a dishwasher cleaning composition according to the first embodiment of the first aspect of the invention of Example 1.

[0061] The limescale removal performance of the dishwasher cleaning composition were tested according to the following test procedures. The limescale removal data for formulations A to I is disclosed in table 1.

[0062] Test Procedure:

[0063] Marble tiles were prepared before testing by wiping with isopropanol, cleaning with deionised water, drained and then dried at 105 °C in a drying cabinet for at least 1 hour. The marble tiles were then cooled and weighed.

[0064] Samples of the first embodiment of the product of the second aspect of the invention comprising one of each formulation A to I was inserted into a dishwasher along with a prepared marble tile 15 minutes after the 65 °C cleaning programme had started. At this point the dishwasher was at 50 °C. The 1 hour cleaning cycle was then run. The tiles were dried and cooled before weighing.

[0065] The limescale removal performance was then calculated as the weight of the tile before testing (g) minus the weight of the tile after testing (g). Table 1

[0066] Control dishwasher cleaning compositions comprising only citric acid or only sodium bisulfate instead of a mixture of citric acid and sodium bisulfate were also tested

[0067] 5 according to the same test procedure. The limescale removal performance of the control samples is presented in table 2.

[0068] 10 Table 2

[0069] The limescale removal data of table 1 and table 2 show that the performance of the inventive dishwasher composition comprising 20 wt.% of a mixture comprising citric acid and sodium bisulfate (formulations A to D and F to G) is superior to the control formulations (1) and (4) which comprise 20 wt.% of citric acid alone or sodium bisulfate alone.

[0070] The limescale removal data of table 1 and table 2 also shows that the performance of the inventive dishwasher composition comprising 14 wt.% of a mixture comprising citric acid and sodium bisulfate (formulations E, H and I) is superior to control formulation (2) and (4) which comprises 15 wt.% of citric acid alone.

[0071] Without being bound by theory it is understood that the acidic proton of sodium bisulfate in combination with the tribasic citric acid synergistically dissolve the calcium salts in limescale and complex hard water Ca2+ ions effectively to reduce formation and / or increase removal of limescale in the dishwasher.

[0072] A second embodiment of a first aspect of the dishwasher cleaning composition of the invention is provided wherein the dishwasher cleaning composition comprises between 10 wt.% and 35 wt.%, preferably 15 wt.% to 20 wt.% of a mixture comprising a tribasic acid and an acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton wherein the tribasic acid is citric acid, and the acid comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton is methane sulfonic acid.

[0073] The second embodiment of the dishwasher cleaning composition is essentially the same as the first embodiment of Example 1 with the exception of the mixture comprising citric acid and methane sulfonic acid instead of citric acid and sodium bisulfate.

[0074] Example formulations J to K of the second embodiment of the invention were provided and the formulations are disclosed in table 3.

[0075] A second embodiment of a second aspect of the product of the invention is provided wherein the product comprises a container comprising a dispensing means, wherein the container comprises a dishwasher cleaning composition according to the second embodiment of the first aspect of the invention of Example 3. The second embodiment of the product of the invention is essentially the same as the first embodiment of the product of the invention of Example 2 except for the dishwasher cleaning composition being the second embodiment of the dishwasher cleaning composition of Example 3.

[0076] The limescale removal performance of the dishwasher cleaning composition were tested according to the above-described test procedure. The limescale removal data for formulations J to L is disclosed in table 3.

[0077] Table 3

[0078] The limescale removal data of table 3 shows desirable limescale removal performance is achieved with the of the inventive dishwasher composition comprising between 16.25 wt.% and 20 wt.% of a mixture comprising citric acid and methane sulfonic acid.

[0079] Without being bound by theory it is understood that the acidic proton of methane sulfonic acid in combination with the tribasic citric acid synergistically dissolve the calcium salts in limescale and complex hard water Ca2+ ions effectively to reduce formation and / or increase removal of limescale in the dishwasher. The acidic proton of 1 methane sulfonic has a lower pKa than the acidic protons of citric acid and therefore they may interact with the ions in limescale and complex hard water before the acidic protons of citric acid thereby increasing the rate of reaction and effectively to reducing the formation of limescale and / or increasing the removal of limescale in the dishwasher.

[0080] A third embodiment of a first aspect of the dishwasher cleaning composition of the invention is provided wherein the dishwasher cleaning composition comprises between 10 wt.% and 35 wt.%, preferably 15 wt.% and 22 wt.% of a mixture comprising a tribasic acid and an acid comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton wherein the tribasic acid is citric acid, and the acid comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton is lactic acid.

[0081] The third embodiment of the dishwasher cleaning composition is essentially the same as the first embodiment of Example 1 with the exception of the mixture comprising citric acid and lactic acid instead of citric acid and sodium bisulfate.

[0082] Example formulations M to P of the second embodiment of the invention were provided and the formulations are disclosed in table 4.

[0083] A third embodiment of a second aspect of the product of the invention is provided wherein the product comprises a container comprising a dispensing means, wherein the container comprises a dishwasher cleaning composition according to the third embodiment of the first aspect of the invention of Example 5. The third embodiment of the product of the invention is essentially the same as the first embodiment of the product of the invention of Example 2 except for the dishwasher cleaning composition being the third embodiment of the first aspect of the invention of Example 5.

[0084] The limescale removal performance of the dishwasher cleaning composition were tested according to the above-described test procedure. The limescale removal data for formulations M to P is disclosed in table 4.

[0085] Table 4

[0086] The limescale removal data of table 4 shows desirable limescale removal performance is achieved with the of the inventive dishwasher composition comprising between 15 wt.% and 22 wt.% of a mixture comprising citric acid and lactic acid.

[0087] Without being bound by theory it is understood that the acidic proton of lactic acid in combination with the tribasic citric acid synergistically dissolve the calcium salts in limescale and complex hard water Ca2+ ions effectively to reduce formation and / or increase removal of limescale in the dishwasher.

[0088] A fourth embodiment of a first aspect of the dishwasher cleaning composition of the invention is provided wherein the dishwasher cleaning composition comprises between 10 wt.% and 35 wt.%, preferably approximately 20 wt.% of a mixture comprising a tribasic acid and an acid comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton wherein the tribasic acid is citric acid, and the acid comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton is sulfamic acid.

[0089] The fourth embodiment of the dishwasher cleaning composition is essentially the same as the first embodiment of Example 1 with the exception of the mixture comprising citric acid and sulfamic acid instead of citric acid and sodium bisulfate.

[0090] Example formulation Q of the fourth embodiment of the invention is provided and the formulation is disclosed in table 5.

[0091] A fourth embodiment of a second aspect of the product of the invention is provided wherein the product comprises a container comprising a dispensing means, wherein the container comprises a dishwasher cleaning composition according to the fourth embodiment of the first aspect of the invention of Example 7. The fourth embodiment of the product of the invention is essentially the same as the first embodiment of the product of the invention of Example 2 except for the dishwasher cleaning composition being the fourth embodiment of the first aspect of the invention of Example 7. The limescale removal performance of the dishwasher cleaning composition was tested according to the above-described test procedure. The limescale removal data for formulation Q is disclosed in table 5.

[0092] Table 5

[0093] The limescale removal data of table 5 shows desirable limescale removal performance is achieved with the of the inventive dishwasher cleaning composition comprising between 20 wt.% of a mixture comprising citric acid and sulfamic acid, in particular the limescale removal performance is superior to control formulation (1) in table 2 which comprises 20 wt.% of citric acid.

[0094] Without being bound by theory it is understood that combination of sulfamic acid and citric acid synergistically dissolves the calcium salts in limescale and complex hard water Ca2+ ions effectively to reduce formation and / or increase removal of limescale in the dishwasher. The acidic proton of sulfamic acid has a lower pKa than the acidic protons of citric acid and therefore they may interact with the ions in limescale and complex hard water before the acidic protons of citric acid thereby increasing the rate of reaction and effectively reduce the formation of limescale and / or increase the removal of limescale in the dishwasher.

[0095] The above embodiments are described by way of example only. Many variations are possible without departing from the scope of the invention as defined in the appended claims.

Claims

1. CLAIMS1. A dishwasher-cleaning composition comprising between 10 wt.% and 35 wt.% of a mixture comprising a tribasic acid or salt thereof, preferably citric acid or a citric acid salt, and an acid or an acid salt; wherein said acid or acid salt comprises a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton.

2. A dishwasher cleaning composition according to claim 1 wherein said acid or acid salt comprises a total of 1 to 3 atoms selected from C, S or a combination thereof and 1 or 2 acidic protons.

3. A dishwasher cleaning composition according to claim 1 or claim 2 wherein said acid or acid salt is selected from the group consisting of lactic acid, sulfamic acid, methanesulfonic acid and sodium bisulfate.

4. A dishwasher cleaning composition according to any preceding claim wherein the amount of the tribasic acid or salt thereof in the mixture is at least 15 wt.%, preferably at least 25 wt.%, and more preferably at least 35 wt.% of the weight of the mixture, in particular at least 50 wt.% of the weight of the mixture.

5. A dishwasher cleaning composition according to any preceding claim wherein the ratio of the tribasic acid or salt thereof and the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton is between 1:3 and 7:1.

6. A dishwasher cleaning composition according to any preceding claim wherein the amount of tribasic acid or salt thereof is between 5 wt.% and 17.5 wt.% of the weight of the dishwasher cleaning composition.

7. A dishwasher cleaning composition according to any preceding claim wherein the amount of acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton is between 2.5 wt.% and 15 wt.% of the weight of the dishwasher cleaning composition.

8. A dishwasher cleaning composition according to any preceding claim wherein the acid or acid salt comprising a total of 1 to 3 atoms selected from C, S or a combination thereof and at least 1 acidic proton comprises a pKa of between -2 and 4; preferably a pKa of between -2 and 0.

9. A dishwasher cleaning composition according to any preceding claim comprising no more than 5 wt. % of a complexing agent, preferably no more than 1 wt. %.

10. A dishwasher cleaning composition according to claim 9 wherein the complexing agent is selected from the group consisting of: 1 -hydroxy ethylidene-l,l-diphosphonic acid (HEDP), methylglycine diacetic acid (MGDA) and tetrasodium glutamate diacetate (GLDA).

11. A dishwasher cleaning composition according to any preceding claim wherein the mixture is a homogeneous liquid and / or an aqueous solution.

12. A dishwasher cleaning composition according to any preceding claim wherein the dishwasher cleaning composition is a liquid.

13. A dishwasher cleaning composition according to claim 12 wherein the dishwasher cleaning composition is a mono-, bi- or triphasic liquid.

14. A dishwasher cleaning composition according to claim 13 wherein the dishwasher cleaning composition is a bi- or triphasic liquid; and wherein themixture is within one phase while at least one other phase comprises a surfactant and preferably at least one dye.

15. A product comprising a container comprising a dispensing means, wherein the container comprises a dishwasher cleaning composition according to any one of claims 1 to 14.

Images