(19)
(11) EP 3 456 808 A1

(12) EUROPEAN PATENT APPLICATION

(43) Date of publication:
20.03.2019 Bulletin 2019/12

(21) Application number: 17190910.4

(22) Date of filing: 13.09.2017
(51) International Patent Classification (IPC): 
C11D 3/00(2006.01)
C11D 3/20(2006.01)
C11D 3/18(2006.01)
C11D 11/00(2006.01)
(84) Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR
Designated Extension States:
BA ME
Designated Validation States:
MA MD

(71) Applicant: The Procter & Gamble Company
Cincinnati, OH 45202 (US)

(72) Inventors:
  • LETZELTER, Nathalie Sophie
    Newcastle upon Tyne, NE12 9TS (GB)
  • STEED, Jonathan William
    Durham, DH1 3LE (GB)
  • HONG, Yuexian
    Durham, DH1 3LE (GB)
  • PRESTON, Karen Margaret
    Newcastle upon Tyne, NE12 9TS (GB)

(74) Representative: Yorquez Ramirez, Maria Isabel 
Procter & Gamble Technical Centres Ltd Newcastle Innovation Centre Whitley Road Longbenton P.O. Box: Forest Hall No. 2
Newcastle Upon Tyne NE12 9TS
Newcastle Upon Tyne NE12 9TS (GB)

   


(54) AUTOMATIC DISHWASHING CLEANING COMPOSITION


(57) A phosphate-free automatic dishwashing cleaning composition comprising a crystal growth inhibitor system comprising cyclohexane-1,2,3,4,5,6-hexacarboxylic acid (CHHCA) and cyclopentane-1,2,3,4-tetracarboxylic acid (CPTCA).


Description

TECHNICAL FIELD



[0001] The present invention is in the field of cleaning. It relates to a cleaning product, in particular, it relates to a phosphate-free automatic dishwashing cleaning composition comprising a crystal growth inhibitor system. The composition provides good shine on plastic and glass items.

BACKGROUND OF THE INVENTION



[0002] Calcium carbonate can deposit on items washed in a dishwasher, depriving the items of shine and leaving them with a dull appearance. Conditions inside dishwashers such as water hardness, high temperature, high pH and high ionic strength all promote the precipitation of calcium carbonate. Calcium carbonate deposition during automatic dishwashing can be reduced by using a crystal growth inhibitor. The most commonly used crystal growth inhibitor has been the tetra sodium salt of 1-hydroxyethane 1,1-diphosphonic acid (HEDP). However, due to its negative environmental impact it is desirable to find more environmentally friendly crystal growth inhibitors.

[0003] Even when a strong chelating builder is added at a level to bind all the calcium in the wash liquor, crystals of calcium carbonate still form and grow having a detriment effect on shine. Several known crystal growth inhibitors contain high levels of phosphorus, something which is not desirable given the environmental profile of such materials.

[0004] Thus, the purpose of the present invention is to improve shine in automatic dishwashing without using detergent ingredients having a negative environmental profile.

SUMMARY OF THE INVENTION



[0005] According to the first aspect of the invention, there is provided a phosphate-free automatic dishwashing cleaning composition. By "phosphate-free" is herein understood that the composition comprises less than 1 %, preferably less than 0.1 % by weight of the composition of phosphate. The composition comprises a crystal growth inhibitor system. The crystal growth inhibitor system comprises cyclohexane-1,2,3,4,5,6-hexacarboxylic acid (CHHCA) and cyclopentane-1,2,3,4-tetracarboxylic acid (CPTCA).

[0006] Crystal growth inhibitors can be highly substrate specific. During the course of this work, it has been found out that: i) cyclohexane-1,2,3,4,5,6-hexacarboxylic acid (CHHCA) is very good to prevent calcium carbonate deposition on glass; and ii) cyclopentane-1,2,3,4-tetracarboxylic acid (CPTCA) is very good to prevent calcium carbonate deposition on plastic (polymethylmethacrylate (PMMA)). When used in combination, these two species prevented all forms of calcium carbonate deposition on both substrate types, glass and plastic.

[0007] Preferably the composition of the invention comprises a complexing agent system. More preferably the complexing agent system comprises a complexing agent selected from the group consisting of citric acid, methyl glycine diacetic acid and its salts, and mixtures thereof. The composition of the invention also provides very good cleaning. The composition of the invention preferably comprises a dispersant polymer, bleach, a bleach activator and enzymes.

[0008] The composition preferably comprises an alkaline-metal carbonate. High levels of alkaline-metal carbonates have been found to be very effective in automatic dishwashing. A drawback associated with high carbonate levels, however, is that calcium ions present in the washing water readily form precipitates with the carbonate that can give rise to filming and spotting.

[0009] The composition provides good shine, in particular on glass and plastic dishware. The composition is environmentally friendly due to the biodegradability of the crystal growth inhibitor system.

[0010] According to the second aspect of the invention, there is provided a method of automatic dishwashing using the composition of the invention. The method provides good shine with an environmentally friendly profile. There is also provided the use of the compositions of the invention to provide shine to glass and plastic items. phosphate-free automatic dishwashing

[0011] The elements of the composition of the first aspect of the invention apply mutatis mutandis to the second and third aspect of the invention.

DETAILED DESCRIPTION OF THE INVENTION



[0012] The present invention encompasses an automatic dishwashing cleaning composition comprising a builder system consisting of a complexing agent and a crystal growth inhibitor system comprising cyclohexane-1,2,3,4,5,6-hexacarboxylic acid (CHHCA) and cyclopentane-1,2,3,4-tetracarboxylic acid (CPTCA). The composition provides very good cleaning and finishing, i.e, reduced filming, spotting and improved shine.

Crystal growth inhibitor system



[0013] The crystal growth inhibitor system comprises cyclohexane-1,2,3,4,5,6-hexacarboxylic acid (CHHCA) and cyclopentane-1,2,3,4-tetracarboxylic acid (CPTCA). CHHCA has been found very good to prevent calcium carbonate deposition on glass and CPTCA has been found very good to prevent calcium carbonate deposition on glass. The system provides similar calcium carbonate deposition prevention similar to that provided by HEDP but it has a better environmental profile. Preferably the composition comprises from 0.1 to 5%, more preferably from 0.2 to 3% by weight of the composition of crystal growth inhibitor system. Preferably CHHCA and CPTCA are in a weight ratio of from 3:7 to 7:3, more preferably from 2:3 to 3:2.

Automatic dishwashing cleaning composition



[0014] The automatic dishwashing cleaning composition can be in any physical form. It can be a loose powder, a gel or presented in unit dose form. Preferably it is in unit dose form, unit dose forms include pressed tablets and water-soluble packs. The automatic dishwashing cleaning composition of the invention is preferably presented in unit-dose form and it can be in any physical form including solid, liquid and gel form. The composition of the invention is very well suited to be presented in the form of a multi-compartment pack, more in particular a multi-compartment pack comprising compartments with compositions in different physical forms, for example a compartment comprising a composition in solid form and another compartment comprising a composition in liquid form. The composition is preferably enveloped by a water-soluble film such as polyvinyl alcohol. Especially preferred are compositions in unit dose form wrapped in a polyvinyl alcohol film having a thickness of less than 100 µm. The detergent composition of the invention weighs from about 8 to about 25 grams, preferably from about 10 to about 20 grams. This weight range fits comfortably in a dishwasher dispenser. Even though this range amounts to a low amount of detergent, the detergent has been formulated in a way that provides all the benefits mentioned herein above.

Complexing agent system



[0015] The complexing agent system comprises one or more complexing agent. A "complexing agent" is a compound capable of binding polyvalent ions such as calcium, magnesium, lead, copper, zinc, cadmium, mercury, manganese, iron, aluminium and other cationic polyvalent ions to form a water-soluble complex. The complexing agent has a logarithmic stability constant ([log K]) for Ca2+ of at least 5, preferably at least 6. The stability constant, log K, is measured in a solution of ionic strength of 0.1, at a temperature of 25° C.

[0016] The complexing agent is selected from the group consisting of methyl-glycine-diacetic acid (MGDA) and its salts, glutamic-N,N- diacetic acid (GLDA) and its salts, iminodisuccinic acid (IDS) and its salts, carboxy methyl inulin and its salts, and mixtures thereof. Especially preferred complexing agent systems comprises an agent selected from the group consisting of MGDA and salts thereof, citric acid and salts thereof, and mixtures thereof. Preferred compositions comprise the three-sodium salt of MGDA or sodium citrate or a mixture of the three-sodium salt of MGDA and sodium citrate.

[0017] Preferably the composition comprises from 10% to 60%, more preferably from 15% to 50% by weight of the composition of the complexing agent system. Compositions comprising a mixture of the three-sodium salt of MGDA and sodium citrate have been found to provide good cleaning and shine. Preferably the three-sodium salt of MGDA and sodium citrate are in a weight ratio of from about 3:7 to about 7:3.

Bleach



[0018] The composition of the invention preferably comprises from about 1 to about 20%, more preferably from about 5 to about 18%, even more preferably from about 8 to about 15% of bleach by weight of the composition.

[0019] Inorganic and organic bleaches are suitable for use herein. Inorganic bleaches include perhydrate salts such as perborate, percarbonate, persulfate and persilicate salts. The inorganic perhydrate salts are normally the alkali metal salts. The inorganic perhydrate salt may be included as the crystalline solid without additional protection. Alternatively, the salt can be coated. Suitable coatings include sodium sulphate, sodium carbonate, sodium silicate and mixtures thereof. Said coatings can be applied as a mixture applied to the surface or sequentially in layers.

[0020] Alkali metal percarbonates, particularly sodium percarbonate is the preferred bleach for use herein. The percarbonate is most preferably incorporated into the products in a coated form which provides in-product stability.

[0021] Potassium peroxymonopersulfate is another inorganic perhydrate salt of utility herein.

[0022] Typical organic bleaches are organic peroxyacids, especially dodecanediperoxoic acid, tetradecanediperoxoic acid, and hexadecanediperoxoic acid. Mono- and diperazelaic acid, mono-and diperbrassylic acid are also suitable herein. Diacyl and Tetraacylperoxides, for instance dibenzoyl peroxide and dilauroyl peroxide, are other organic peroxides that can be used in the context of this invention.

[0023] Further typical organic bleaches include the peroxyacids, particular examples being the alkylperoxy acids and the arylperoxy acids. Preferred representatives are (a) peroxybenzoic acid and its ring-substituted derivatives, such as alkylperoxybenzoic acids, but also peroxy-α-naphthoic acid and magnesium monoperphthalate, (b) the aliphatic or substituted aliphatic peroxy acids, such as peroxylauric acid, peroxystearic acid, ε-phthalimidoperoxycaproic acid[phthaloiminoperoxyhexanoic acid (PAP)], o-carboxybenzamidoperoxycaproic acid, N-nonenylamidoperadipic acid and N-nonenylamidopersuccinates, and (c) aliphatic and araliphatic peroxydicarboxylic acids, such as 1,12-diperoxycarboxylic acid, 1,9-diperoxyazelaic acid, diperoxysebacic acid, diperoxybrassylic acid, the diperoxyphthalic acids, 2-decyldiperoxybutane-1,4-dioic acid, N,N-terephthaloyldi(6-aminopercaproic acid).

Bleach Activators



[0024] Bleach activators are typically organic peracid precursors that enhance the bleaching action in the course of cleaning at temperatures of 60° C and below. Bleach activators suitable for use herein include compounds which, under perhydrolysis conditions, give aliphatic peroxoycarboxylic acids having preferably from 1 to 12 carbon atoms, in particular from 2 to 10 carbon atoms, and/or optionally substituted perbenzoic acid. Suitable substances bear O-acyl and/or N-acyl groups of the number of carbon atoms specified and/or optionally substituted benzoyl groups. Preference is given to polyacylated alkylenediamines, in particular tetraacetylethylenediamine (TAED), acylated triazine derivatives, in particular 1,5-diacetyl-2,4-dioxohexahydro-1,3,5-triazine (DADHT), acylated glycolurils, in particular tetraacetylglycoluril (TAGU), N-acylimides, in particular N-nonanoylsuccinimide (NOSI), acylated phenolsulfonates, in particular n-nonanoyl- or isononanoyloxybenzenesulfonate (n- or iso-NOBS), decanoyloxybenzoic acid (DOBA), carboxylic anhydrides, in particular phthalic anhydride, acylated polyhydric alcohols, in particular triacetin, ethylene glycol diacetate and 2,5-diacetoxy-2,5-dihydrofuran and also triethylacetyl citrate (TEAC). If present the composition of the invention comprises from 0.01 to 5, preferably from 0.2 to 2% by weight of the composition of bleach activator, preferably TAED.

Bleach Catalyst



[0025] The composition herein preferably contains a bleach catalyst, preferably a metal containing bleach catalyst. More preferably the metal containing bleach catalyst is a transition metal containing bleach catalyst, especially a manganese or cobalt-containing bleach catalyst.

[0026] Bleach catalysts preferred for use herein include manganese triazacyclononane and related complexes; Co, Cu, Mn and Fe bispyridylamine and related complexes; and pentamine acetate cobalt(III) and related complexes.

[0027] Preferably the composition of the invention comprises from 0.001 to 0.5, more preferably from 0.002 to 0.05% of bleach catalyst by weight of the composition. Preferably the bleach catalyst is a manganese bleach catalyst.

Builder



[0028] The composition of the invention preferably comprises a builder. Suitable builders are selected from the group consisting of carbonate, silicate and mixtures thereof. Especially preferred for use herein is sodium carbonate. Preferably, the composition is free of silicate. Preferably the composition of the invention comprises from 5 to 50%, more preferably from 10 to 45% and especially from 15 to 35% of sodium carbonate by weight of the composition.

Polymers



[0029] Polymers, if used, can be used in any suitable amount from about 0.1 to about 20%, preferably from 0.2 to about 15%, more preferably from 0.5 to 10% by weight of the composition Polymers include sulfonated derivatives of polycarboxylic acids and may comprise two, three, four or more different monomer units. The preferred copolymers contain:

[0030] At least one structural unit derived from a carboxylic acid monomer having the general formula (III):

wherein R1 to R3 are independently selected from hydrogen, methyl, linear or branched saturated alkyl groups having from 2 to 12 carbon atoms, linear or branched mono or polyunsaturated alkenyl groups having from 2 to 12 carbon atoms, alkyl or alkenyl groups as aforementioned substituted with -NH2 or -OH, or -COOH, or COOR4, where R4 is selected from hydrogen, alkali metal, or a linear or branched, saturated or unsaturated alkyl or alkenyl group with 2 to 12 carbons;

[0031] Preferred carboxylic acid monomers include one or more of the following: acrylic acid, maleic acid, maleic anhydride, citraconic acid, 2-phenylacrylic acid, cinnamic acid, crotonic acid, fumaric acid, methacrylic acid, 2-ethylacrylic acid, methylenemalonic acid, or sorbic acid. Acrylic and methacrylic acids being more preferred.

[0032] Optionally, one or more structural units derived from at least one nonionic monomer having the general formula (IV):



[0033] Wherein R5 to R7 are independently selected from hydrogen, methyl, phenyl or hydroxyalkyl groups containing 1 to 6 carbon atoms, and can be part of a cyclic structure, X is an optionally present spacer group which is selected from -CH2-, -COO-, -CONH- or -CONR8-, and R8 is selected from linear or branched, saturated alkyl radicals having 1 to 22 carbon atoms or unsaturated, preferably aromatic, radicals having from 6 to 22 carbon atoms.

[0034] Preferred non-ionic monomers include one or more of the following: butene, isobutene, pentene, 2-methylpent-1-ene, 3-methylpent-1-ene, 2,4,4-trimethylpent-1-ene, 2,4,4-trimethylpent-2-ene, cyclopentene, methylcyclopentene, 2-methyl-3-methyl-cyclopentene, hexene, 2,3-dimethylhex-1-ene, 2,4-dimethylhex-1-ene, 2,5-dimethylhex-1-ene, 3,5-dimethylhex-1-ene, 4,4-dimethylhex-1-ene, cyclohexene, methylcyclohexene, cycloheptene, alpha olefins having 10 or more carbon atoms such as, dec-1-ene, dodec-1-ene, hexadec-1-ene, octadec-1-ene and docos-1-ene, preferred aromatic monomers are styrene, alpha methylstyrene, 3-methylstyrene, 4-dodecylstyrene, 2-ethyl-4-bezylstyrene, 4-cyclohexylstyrene, 4-propylstyrol, 1-vinylnaphtalene, 2-vinylnaphtalene; preferred carboxylic ester monomers are methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate and behenyl (meth)acrylate; preferred amides are N-methyl acrylamide, N-ethyl acrylamide, N-t-butyl acrylamide, N-2-ethylhexyl acrylamide, N-octyl acrylamide, N-lauryl acrylamide, N-stearyl acrylamide, N-behenyl acrylamide and at least one structural unit derived from at least one sulfonic acid monomer having the general formula (V) and (VI):



wherein R7 is a group comprising at least one sp2 bond, A is O, N, P, S, an amido or ester linkage, B is a mono- or polycyclic aromatic group or an aliphatic group, each t is independently 0 or 1, and M+ is a cation. In one aspect, R7 is a C2 to C6 alkene. In another aspect, R7 is ethene, butene or propene.

[0035] Preferred sulfonated monomers include one or more of the following: 1-acrylamido-1-propanesulfonic acid, 2-acrylamido-2-propanesulfonic acid, 2-acrylamido-2-methyl-1-propanesulfonic acid, 2-methacrylamido-2-methyl-1-propanesulfonic acid, 3- methacrylamido-2-hydroxy-propanesulfonic acid, allylsulfonic acid, methallylsulfonic acid, allyloxybenzenesulfonic acid, methallyloxybenzenesulfonic acid, 2-hydroxy-3- (2-propenyloxy) propanesulfonic acid, 2-methyl-2-propen-1-sulfonic acid, styrenesulfonic acid, vinylsulfonic acid, 3-sulfopropyl, 3-sulfo-propylmethacrylate, sulfomethacrylamide, sulfomethylmethacrylamide and mixtures of said acids or their water-soluble salts.

[0036] Preferably, the polymer comprises the following levels of monomers: from about 40 to about 90%, preferably from about 60 to about 90% by weight of the polymer of one or more carboxylic acid monomer; from about 5 to about 50%, preferably from about 10 to about 40% by weight of the polymer of one or more sulfonic acid monomer; and optionally from about 1% to about 30%, preferably from about 2 to about 20% by weight of the polymer of one or more non-ionic monomer. An especially preferred polymer comprises about 70% to about 80% by weight of the polymer of at least one carboxylic acid monomer and from about 20% to about 30% by weight of the polymer of at least one sulfonic acid monomer.

[0037] In the polymers, all or some of the carboxylic or sulfonic acid groups can be present in neutralized form, i.e. the acidic hydrogen atom of the carboxylic and/or sulfonic acid group in some or all acid groups can be replaced with metal ions, preferably alkali metal ions and in particular with sodium ions.

[0038] The carboxylic acid is preferably (meth)acrylic acid. The sulfonic acid monomer is preferably 2-acrylamido-2-propanesulfonic acid (AMPS).

[0039] Preferred commercial available polymers include: Alcosperse 240, Aquatreat AR 540 and Aquatreat MPS supplied by Alco Chemical; Acumer 3100, Acumer 2000, Acusol 587G and Acusol 588G supplied by Rohm & Haas; Goodrich K-798, K-775 and K-797 supplied by BF Goodrich; and ACP 1042 supplied by ISP technologies Inc. Particularly preferred polymers are Acusol 587G and Acusol 588G supplied by Rohm & Haas.

[0040] Other polymers include anionic carboxylic polymer of low molecular weight. They can be homopolymers or copolymers with a weight average molecular weight of less than or equal to about 200,000 g/mol, or less than or equal to about 75,000 g/mol, or less than or equal to about 50,000 g/mol, or from about 3,000 to about 50,000 g/mol, preferably from about 5,000 to about 45,000 g/mol. The other polymer may be a low molecular weight homopolymer of polyacrylate, with an average molecular weight of from 1,000 to 20,000, particularly from 2,000 to 10,000, and particularly preferably from 3,000 to 5,000.

[0041] Other polymer may be a copolymer of acrylic with methacrylic acid, acrylic and/or methacrylic with maleic acid, and acrylic and/or methacrylic with fumaric acid, with a molecular weight of less than 70,000. Their molecular weight ranges from 2,000 to 80,000 and more preferably from 20,000 to 50,000 and in particular 30,000 to 40,000 g/mol. and a ratio of (meth)acrylate to maleate or fumarate segments of from 30:1 to 1:2.

[0042] Other polymer may be a copolymer of acrylamide and acrylate having a molecular weight of from 3,000 to 100,000, alternatively from 4,000 to 20,000, and an acrylamide content of less than 50%, alternatively less than 20%, by weight of the other polymer can also be used. Alternatively, such polymer may have a molecular weight of from 4,000 to 20,000 and an acrylamide content of from 0% to 15%, by weight of the polymer.

[0043] Alternatively, the polymer can be selected from the group consisting of alkoxylated polyalkyleneimines, alkoxylated polycarboxylates, polyethylene glycols, styrene co-polymers, cellulose sulfate esters, carboxylated polysaccharides, amphiphilic graft copolymers and mixtures thereof.

[0044] The composition of the invention can be free of polymers.

Surfactant



[0045] Surfactants suitable for use herein include non-ionic surfactants, preferably the compositions are free of any other surfactants. Traditionally, non-ionic surfactants have been used in automatic dishwashing for surface modification purposes in particular for sheeting to avoid filming and spotting and to improve shine. It has been found that non-ionic surfactants can also contribute to prevent redeposition of soils.

[0046] Preferably the composition of the invention comprises a non-ionic surfactant or a non-ionic surfactant system, more preferably the non-ionic surfactant or a non-ionic surfactant system has a phase inversion temperature, as measured at a concentration of 1% in distilled water, between 40 and 70°C, preferably between 45 and 65°C. By a "non-ionic surfactant system" is meant herein a mixture of two or more non-ionic surfactants. Preferred for use herein are non-ionic surfactant systems. They seem to have improved cleaning and finishing properties and better stability in product than single non-ionic surfactants.

[0047] Phase inversion temperature is the temperature below which a surfactant, or a mixture thereof, partitions preferentially into the water phase as oil-swollen micelles and above which it partitions preferentially into the oil phase as water swollen inverted micelles. Phase inversion temperature can be determined visually by identifying at which temperature cloudiness occurs.

[0048] The phase inversion temperature of a non-ionic surfactant or system can be determined as follows: a solution containing 1% of the corresponding surfactant or mixture by weight of the solution in distilled water is prepared. The solution is stirred gently before phase inversion temperature analysis to ensure that the process occurs in chemical equilibrium. The phase inversion temperature is taken in a thermostable bath by immersing the solutions in 75 mm sealed glass test tube. To ensure the absence of leakage, the test tube is weighed before and after phase inversion temperature measurement. The temperature is gradually increased at a rate of less than 1°C per minute, until the temperature reaches a few degrees below the pre-estimated phase inversion temperature. Phase inversion temperature is determined visually at the first sign of turbidity.

[0049] Suitable nonionic surfactants include: i) ethoxylated non-ionic surfactants prepared by the reaction of a monohydroxy alkanol or alkyphenol with 6 to 20 carbon atoms with preferably at least 12 moles particularly preferred at least 16 moles, and still more preferred at least 20 moles of ethylene oxide per mole of alcohol or alkylphenol; ii) alcohol alkoxylated surfactants having a from 6 to 20 carbon atoms and at least one ethoxy and propoxy group. Preferred for use herein are mixtures of surfactants i) and ii).

[0050] Other suitable non-ionic surfactants are epoxy-capped poly(oxyalkylated) alcohols represented by the formula:

         R1O[CH2CH(CH3)O]x[CH2CH2O]y[CH2CH(OH)R2]     (I)

wherein R1 is a linear or branched, aliphatic hydrocarbon radical having from 4 to 18 carbon atoms; R2 is a linear or branched aliphatic hydrocarbon radical having from 2 to 26 carbon atoms; x is an integer having an average value of from 0.5 to 1.5, more preferably about 1; and y is an integer having a value of at least 15, more preferably at least 20.

[0051] Preferably, the surfactant of formula I, at least about 10 carbon atoms in the terminal epoxide unit [CH2CH(OH)R2]. Suitable surfactants of formula I, according to the present invention, are Olin Corporation's POLY-TERGENT® SLF-18B nonionic surfactants, as described, for example, in WO 94/22800, published October 13, 1994 by Olin Corporation.

Enzymes



[0052] In describing enzyme variants herein, the following nomenclature is used for ease of reference: Original amino acid(s):position(s):substituted amino acid(s). Standard enzyme IUPAC 1-letter codes for amino acids are used.

Proteases



[0053] The composition of the invention is beneficial in terms of removal of proteinaceous soils, in particular sugary burn soils such as crème brulee.

[0054] Suitable proteases include metalloproteases and serine proteases, including neutral or alkaline microbial serine proteases, such as subtilisins (EC 3.4.21.62) as well as chemically or genetically modified mutants thereof. Suitable proteases include subtilisins (EC 3.4.21.62), including those derived from Bacillus, such as Bacillus lentus, B. alkalophilus, B. subtilis, B. amyloliquefaciens, Bacillus pumilus and Bacillus gibsonii.

[0055] Especially preferred proteases for the detergent of the invention are polypeptides demonstrating at least 90%, preferably at least 95%, more preferably at least 98%, even more preferably at least 99% and especially 100% identity with the wild-type enzyme from Bacillus lentus, comprising mutations in one or more, preferably two or more and more preferably three or more of the following positions, using the BPN' numbering system and amino acid abbreviations as illustrated in WO00/37627, which is incorporated herein by reference:V68A, N87S, S99D, S99SD, S99A, S101G, S101M, S103A, V104N/I, G118V, G118R, S128L, P129Q, S130A, Y167A, R170S, A194P, V205I and/or M222S.

[0056] Most preferably the protease is selected from the group comprising the below mutations (BPN' numbering system) versus either the PB92 wild-type (SEQ ID NO:2 in WO 08/010925) or the subtilisin 309 wild-type (sequence as per PB92 backbone, except comprising a natural variation of N87S).
  1. (i) G118v + S128L + P129Q + S130A
  2. (ii) S101M + G118V + S128L + P129Q + S130A
  3. (iii) N76D + N87R + G118R + S128L + P129Q + S130A + S188D + N248R
  4. (iv) N76D + N87R + G118R + S128L + P129Q + S130A + S188D + V244R
  5. (v) N76D + N87R + G118R + S128L + P129Q + S130A
  6. (vi) V68A + N87S + S101G + V104N


[0057] Suitable commercially available protease enzymes include those sold under the trade names Savinase®, Polarzyme®, Kannase®, Ovozyme®, Everlase® and Esperase® by Novozymes A/S (Denmark), those sold under the tradename Properase®, Purafect®, Purafect Prime®, Purafect Ox®, FN3® , FN4®, Excellase®, Ultimase® and Purafect OXP® by Genencor International, those sold under the tradename Opticlean® and Optimase® by Solvay Enzymes, those available from Henkel/ Kemira, namely BLAP.

[0058] Preferred levels of protease in the composition of the invention include from about 0.2 to about 2 mg of active protease per grams of the composition.

Amylases



[0059] The composition of the invention can comprise amylases. A preferred alkaline amylase is derived from a strain of Bacillus, such as Bacillus licheniformis, Bacillus amyloliquefaciens, Bacillus stearothermophilus, Bacillus subtilis, or other Bacillus sp., such as Bacillus sp. NCIB 12289, NCIB 12512, NCIB 12513, DSM 9375 (USP 7,153,818) DSM 12368, DSMZ no. 12649, KSM AP1378 (WO 97/00324), KSM K36 or KSM K38 (EP 1,022,334). Preferred amylases include:
  1. (a) the variants described in US 5,856,164 and WO99/23211, WO 96/23873, WO00/60060 and WO 06/002643, especially the variants with one or more substitutions in the following positions versus the AA560 SEQ ID No. 3:

    9, 26, 30, 33, 82, 37, 106, 118, 128, 133, 149, 150, 160, 178, 182, 186, 193, 195, 202, 214, 231, 256, 257, 258, 269, 270, 272, 283, 295, 296, 298, 299, 303, 304, 305, 311, 314, 315, 318, 319, 320, 323, 339, 345, 361, 378, 383, 419, 421, 437, 441, 444, 445, 446, 447, 450, 458, 461, 471, 482, 484, preferably that also contain the deletions of D183* and G184*.

  2. (b) variants exhibiting at least 95% identity with the wild-type enzyme from Bacillus sp.707 (SEQ ID NO:7 in US 6,093, 562), especially those comprising one or more of the following mutations M202, M208, S255, R172, and/or M261. Preferably said amylase comprises one of M202L or M202T mutations.


[0060] Suitable commercially available alpha-amylases include DURAMYL®, LIQUEZYME®, TERMAMYL®, TERMAMYL ULTRA®, NATALASE®, EVEREST®, SUPRAMYL®, STAINZYME®, STAINZYME PLUS®, FUNGAMYL® and BAN® (Novozymes A/S, Bagsvaerd, Denmark), KEMZYM® AT 9000 Biozym Biotech Trading GmbH Wehlistrasse 27b A-1200 Wien Austria, RAPIDASE®, PURASTAR®, ENZYSIZE®, OPTISIZE HT PLUS®, POWERASE®, EXCELLENZ™ S series, including EXCELLENZ™ S 1000 and EXCELLENZ™ S 2000 and PURASTAR OXAM® (DuPont Industrial Biosciences., Palo Alto, California) and KAM® (Kao, 14-10 Nihonbashi Kayabacho, 1-chome, Chuo-ku Tokyo 103-8210, Japan). Amylases especially preferred for use herein include NATALASE®, STAINZYME®, STAINZYME PLUS®, EXCELLENZ™ S 1000, EXCELLENZ™ S2000 and mixtures thereof.

[0061] Preferably, the composition of the invention comprises at least 0.005 mg, preferably from about 0.0025 to about 0.025, more preferably from about 0.05 to about 0.3, especially from about 0.01 to about 0.25 mg of active amylase.

[0062] Preferably, the protease and/or amylase of the composition of the invention are in the form of granulates, the granulates comprise more than 29% of sodium sulfate by weight of the granulate and/or the sodium sulfate and the active enzyme (protease and/or amylase) are in a weight ratio of between 3:1 and 100:1 or preferably between 4:1 and 30:1 or more preferably between 5:1 and 20:1.

Metal Care Agents



[0063] Metal care agents may prevent or reduce the tarnishing, corrosion or oxidation of metals, including aluminium, stainless steel and non-ferrous metals, such as silver and copper. Preferably the composition of the invention comprises from 0.1 to 5%, more preferably from 0.2 to 4% and especially from 0.3 to 3% by weight of the product of a metal care agent, preferably the metal care agent is benzo triazole (BTA).

Glass Care Agents



[0064] Glass care agents protect the appearance of glass items during the dishwashing process. Preferably the composition of the invention comprises from 0.1 to 5%, more preferably from 0.2 to 4% and specially from 0.3 to 3% by weight of the composition of a metal care agent, preferably the glass care agent is a zinc containing material, specially hydrozincite.

[0065] The automatic dishwashing composition of the invention preferably has a pH as measured in 1% weight/volume aqueous solution in distilled water at 25°C of greater than 10, more preferably greater than 10.5.

[0066] The automatic dishwashing composition of the invention preferably has a reserve alkalinity of from about 10 to about 20, more preferably from about 12 to about 18 at a pH of 9.5 as measured in NaOH with 100 grams of product at 20°C.

[0067] A preferred automatic dishwashing composition of the invention comprises:
  1. a) from 0.1 to 5% by weight thereof of the crystal growth inhibitor system;
  2. b) from 5 to 40% by weight thereof of a complexing agent;
  3. c) from 5 to 40% by weight thereof of an alkali metal carbonate;
  4. d) an amylase and a protease;
  5. e) from 1 to 30% by weight thereof of bleach; and
  6. f) from 0 to 10% by weight thereof of a dispersant polymer.

EXAMPLES


Inhibition Performance Screening



[0068] The inhibition efficiency of a series of commercially available cyclic polycarboxylic acids was evaluated in hard water using a dishwashing detergent in a model system.

[0069] A series of commercially available cyclic polycarboxylic acids with 5-, 6-, 10- and 12-membered rings with two or more carboxylic acid groups were evaluated (Figure 1). A further phosphorus-containing compound phytic acid (PA - a saturated cyclic acid that can be found in cereals and grains35) was also evaluated. The inhibition performance of the selected inhibitors, except CHTTCA, was evaluated at the same concentration as HEDP (0.112 mmol L-1). CHTTCA is a mixture of cis- and trans- isomers, hence double the amount was used.











Table 1. Dishwashing detergent.
Ingredient Raw material in water (g L-1)
Trisodium salt of methylglycinediacetic acid 0.564
Granular sodium carbonate 1.908
Sodium sulphate 0.612
Sulfonated polyacrylates Acusol 588 0.258
Non-ionic surfactant 0.350


[0070] Model Dishwasher System: in the model set-up used to evaluate the performance of cyclic polycarboxylic acids, substrates are fixed near the top of a glass container. A hot plate with a thermometer is used to maintain the temperature at 65 °C. The stirring speed is kept at a rate of 100 rpm, enough to disperse the detergent but not cause agitation effects. PMMA (polymethylmethacrylate) sheets and glass sheets are fixed in pairs near the top of the glass container. Hard water was prepared by dissolving CaCl2 (0.1526 g, 2.75 mmol L-1) and MgCl2 (0.04805 g, 0.0806 mmol L-1) in 500 mL deionized water (DI water). This solution was then transferred into the glass container and heated up to 65°C, before the addition of the dishwashing detergent (Table 1).

[0071] HEDP with its high inhibition efficiency and consequent retention of 'shine' for any substrate under dishwasher conditions, serves as a standard effective inhibitor. Deposition of calcium carbonate on glass and PMMA substrates at 65 °C in simulated hard water in the presence of the nil-HEDP detergent formula for five cycles of 60 minutes each, acts as a control experiment for the inhibition performance of the candidate inhibitors.

[0072] The inhibition performance of the candidate inhibitors can be simply evaluated by visual inspection. Typically, for most of the inhibitors tested, film formation was observed by naked eye on the surface after two or three cycles. Candidate inhibitors that were capable of retaining the shine as efficiently as HEDP after five cycles, were deemed as an effective inhibitors and noted as 'pass.' Otherwise, they were labeled as 'fail.' Some candidate inhibitors exhibited some inhibition ability in the first cycle, with film formation occurring in subsequent cycles, were also deemed ineffective. The screening outcomes of twenty-nine differernt candidate inhibitors including HEDP are given in 2.

[0073] Table 2. The inhibition performance screening results after three cycles. The best-performing inhibitors (HEDP, PA and 1: 1 mixture of CPTCA and CHHCA') were run for five cycles. 'pass' means that a fully shiny surface was retained, while 'fail' means some observable film formation on the surface. A concentration of 0.112 mmol L-1 is used in all cases.
Table 2
No. Inhibitor Glass PMMA No. Inhibitor Glass PMMA
1 HEDP pass pass 16 PA pass pass
2 TMCPDA fail fail 17 GTA fail fail
3 CPDA fail fail 18 DHDAD fail fail
4 CPTCA fail pass 19 GA fail fail
5 THFTCA fail fail 20 PDA-12 fail fail
6 FA fail fail 21 PDA-13 fail fail
7 QA fail fail 22 SPS fail fail
8 CHDAA fail fail 23 BTCA fail fail
9 CHDA fail fail 24 BTTCA fail fail
10 CHTCA-135 fail fail 25 BPCA fail fail
11 CHTCA-124 fail fail 26 BHCA fail fail
12 TPCHTCA fail fail 27 DPA fail fail
13 CPTTCA fail fail 28 PZDA fail fail
14 CHHCA pass fail 29 GTDH fail fail
15 CPTCA + CHHCA pass pass 30 TTCDTCA fail fail


[0074] As it can be seen from Table 2 the combination of CHHCA and CPTCA provide an effective replacement for HEDP.

[0075] A 1:1 mixture of CPTCA and CHHCA from the initial screening test, were further evaluated in a real dishwasher up to 30 cycles. The test materials used were glass and polystyrene tumblers. The inhibition of filming on both substrates was comparable to that of the phosphorus-based systems (PA or HEDP).

[0076] The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as "40 mm" is intended to mean "about 40 mm".


Claims

1. A phosphate-free automatic dishwashing cleaning composition comprising a crystal growth inhibitor system comprising cyclohexane-1,2,3,4,5,6-hexacarboxylic acid (CHHCA) and cyclopentane-1,2,3,4-tetracarboxylic acid (CPTCA).
 
2. A composition according to claim 1 wherein the composition comprises from 0.1 to 5% by weight thereof of the crystal growth inhibitor system.
 
3. A composition according to any of the preceding claims further comprising a complexing agent system wherein the complexing agent system comprises at least one complexing agent selected from the group consisting of citric acid, methyl glycine diacetic acid, glutamic-N,N- diacetic acid, iminodisuccinic acid, carboxy methyl inulin, its salts, and mixtures thereof.
 
4. A composition according to the preceding claim wherein the complexing agent is selected from the group consisting of citric acid, methyl glycine diacetic acid and its salts, and mixtures thereof.
 
5. A composition according to the preceding wherein the complexing agent system comprises at least 30% by weight thereof of sodium citrate.
 
6. A composition according to any of claims 3 or 4 comprising from 10% to 60% by weight thereof of the complexing agent system.
 
7. A composition according to any of the preceding claims further comprising an alkali metal carbonate.
 
8. A composition according to any of the preceding claims further comprising a dispersant polymer, preferably a carboxylated/sulfonated polymer.
 
9. A composition according to any of the preceding claims further comprising bleach and preferably a bleach activator.
 
10. A composition according to any of the preceding claims wherein the composition has a pH greater than 10 as measured in a 1% weight aqueous solution at 25°C.
 
11. A composition according to any of the preceding claims comprising:

a) from 0.1 to 5% by weight thereof of the crystal growth inhibitor system;

b) from 5 to 40% by weight thereof of a complexing agent;

c) from 5 to 40% by weight thereof of an alkali metal carbonate;

d) an amylase and a protease;

e) from 1 to 30% by weight thereof of bleach; and

f) from 0 to 10% by weight thereof of a dispersant polymer.


 
12. A method of washing a dishware/tableware load comprising plastic and glass items comprising the step of washing the load in a dishwasher using a composition according to any of the preceding claims.
 
13. Use of a phosphate-free automatic dishwashing composition comprising a crystal growth inhibitor system comprising cyclohexane-1,2,3,4,5,6-hexacarboxylic acid (CHHCA) and cyclopentane-1,2,3,4-tetracarboxylic acid (CPTCA) to provide shine to plastic and glass items in automatic dishwashing.
 





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Search report




Cited references

REFERENCES CITED IN THE DESCRIPTION



This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

Patent documents cited in the description