CA1279801C - Detergent compositions - Google Patents

Abstract

DETERGENT COMPOSITIONS

ABSTRACT

A granular detergent composition containing about 6% to 18%
aluminosilicate cation exchange material (a), about 1% to 8%
nitrilotriacetate (b), about 6% to 14% phosphate builder selected from sodium and potassium tripolyphoyphates with less than 12% thereof as pyrophosphate, about 5% to 35% bleaching agent, up to 10% organic peroxy acid bleach precursor, and a heavy metal scavenging agent, wherein the percentage quantities of (a) and 2(b) is from 13 to 27. The compositions display improved bleaching, cleaning and fabric damage at low aluminosilicate levels.

Description

~L~79801 DETERGE~T COMPOSITIONS

The present invention rslates to detergent compositions. In particular, it relates to built laundry detergent compositions having reduced phosphate levels together with excellent cleaning, whitene~s maintenance and stain-removal performance as well as improved bleach stability and fabric-care characteristic~
The role of phosphate detergency builders as adjuncts for organic, water-soluble, synthetic detergents and their . val-u-e in~improving the--overall performance o~ such~detergents are well-~nown. In recent years, however, the u-~e of high levels of phosphate builders, such as the tripolypho~phates, has co~e under scru~iny because of the ~uspicion that soluble phosphate qpecies accelerate the eutrophication or ageing process of water bodies. The need exi~s, therefore for a built laundry detergent co~po~ition with reduced pho~phate levels bllt which is comparable to a conventional tripolyphosphate-built composition in overall detergency e~fectivene B.
The mechanism whereby detergency buildera function to improve the detergency action of water-soluble organic detergent compound3 is not preci~ely known, but appears to depend on a combination o~ such factors as water-softening action, 80il suspen~ion and anti-redeposition ef~ect~, clay ~welling and peptization and pH adjustment. However, present theory does not allow the prediction of which compounds will serve as e~fective detergency builders.

79~1 .

Sodium aluminosilicates, ~ommonly known as zeolites have been proposed for use a~ phosphate builder substitutes since they are able to soften water by removing calcium ions (see, for example, BE~A-814,874 and BE-A-813581). Zeolite~ are unable to duplicate the full range of builder functions demonstrated by phosphates, however.
One way of boosting the overall detergency of low-pho~phate formulations is through the use of bleaching auxiliaries such as the inorganic or organic peroxy bleaches and organic bleach activators. Although careful rebalancing of builder and bleach types and levels can indeed provide some improvement in performance, such formulations remain fundamentally weak in three areas, firstly bleach stability, secondly fabric damage characteristics, and thirdly, greasy and particulate soil removal especially at low wash temperatures.
In EP-A-70,079 it has been proposed to improve the bleach ~erformance of aluminosilicate built compositions by addition thereto of a nitrilotriacetic acid compoundA The combined level of aluminosilicate and nitrilotriacetate was said to be critical and corresponded to a relatively high total level in the final produc~. At high concentrations, however, aluminosilicates and nitrilotriacetates both present significant processing problems, the alumino~ilicates raising problems with dispersion stability and pumping characteristics while the nitrilotriacetates raising thermal 3tability problems. Moreover, high levels of aluminosilicates can also deleteriously efect fabric appearance. Where, on the other hand, the aluminosilicate and nitrilotriacetate levels are reduced into a more acceptable range, bleaching, cleaning performance and fabric damage characteristics are once again adversely effected.
It has now been discovered that bleaching, cleaning performance and fabric damage chaxacteristics can be significantly improved, even in the context of a relatively low total level o~ alumino~ilicate and nitrilotriacetate, by ~'7~3;3()~L

the addition thereto of a tripolyphosphate builder in defined amounts with a critical maxi~um limitation on pyrophosphate content. Moreover, it ha~ been further discovered that certain organic peroxy acid bleach precursors of defined chain length are operable in combination with the low-phosphate builder ~ystem to provide cleaning perfor~ance which is at least equivalent to a fully pho~phate-built formulation across the range of wash temperatures with particularly outstanding performance on greasy and particulate soils at low wash temperatures.
Thus, according ~o the invention, there is provided a detergent composition comprising (a) from about 6% to about 18~ by weight of a water-insoluble aluminosilicate cation exchange material, (b) from about 1% to about 8% of an alkali metal salt of nitrilotriacetic acid, (c) from about-6% to a~out 14~ of pho~phate builder, the`
phosphate builder being selected from sodium and potassium tripolyphosphates and comprising less than about 12% thereof of pyrophosphate, (d) from about 5% to about 35~ of inorganic or organic peroxy bleaching agent, (e) from 0% to about 10% of organic peroxy acid bleach precursor, and (f) a heavy metal scavenging agent, wherein th~ percentage quan~ities of (a) + 2 (b) is between about 13 and about 27.
The compo~itions of the invention contain a specified - detergent builder system and a bleach system. In addition, the compositions will generally include an organic soap or synthetic detergent surfactant material. Highly preferred compositions also contain defined levels of polycarboxylate polymers, alkali metal carbonate and alkali metal silicate designed to provide improved detergency and fabric appearance characteri~tics.

~-~'73~

The builder system comprises three essential components, a water-insoluble alumino~ilicate cation exchange material, an alkali metal salt of nitrilotriacetic acid, and a phosphate builder.
The aluminosilicake cation exchange material comprises from about 6% ~o about 18%, preferably from about 7% to about 16%, and more preferably from about 8% to about 14~ by weight of the detergent composition. The aluminosilicate can be crystalline or amorphous in character, preferred materials having ~he unit cell ~ormula I

Mz ~(A102)z (SiO2~y] xH20 wherein M is a calcium-exchange cation, z and y are at least 6: the ~olar ratio of z to y is fro~ about 1.0 to about O.S
and x i5 at least 5, preferably from about 7u5 to about 276, more ~referably from about 10 to about 264. The - aluminosilicate ~aterials are in-hydrated form and are-preferably crystalline containing from about 10~ to about 28%, more preferably from about 18% to about 22% water.
The aluminosilicate ion exchange materials are further characterized by a particle size diameter of from about 0.1 micron to about 10 microns, preferably from about 0.2 micron to about 4 microns. The term "particle size diameter"
herein represents the average particle size diameter of a given ion exchange material as determined by conven~ional analytical techniques such as, for example, microscopic determination utilizing a scanning electron microscope. The aluminosilicate ion exchange materials herein are u~ually further characterised by their calcium ion-exchange capacity, which is at least about 200 mg. equivalent of CaC03 water hardness/g of aluminosilicate, calculated on an anhydrous basis, and which generally is in the range of from about 300 mg eq./g to about 352 mg eq./g. The alumino~ilicate ion exchange materials herein are still further characterized by their calcium ion exchange rate which is at least about 2 _ S _ grains Ca++/gallon/minute/gram/gallon of aluminosilicate (anhydrou~ basi~), and generally lies within the range of from about 2 grainR/gallon/minute/yram/gallon to about 6 qrains/gallon/minute/gram/gallon, based on calcium ion 5 hardness. Optimum alumino~ilicate~ for builder purposes exhibit a calcium ion exchange rate of at leaæt about 4 grains/gallon/minute/gram/gallon.
Aluminosilicate ion exchange materials useful in ~he practice of this invention are commercially available and can 10 be naturally occurring aluminosili~ates or syn~hetically derived. A method for producing aluminosilicate ion exchange materials is discussed in U.S~-A-3,985,6690 Preferred synthetic crystalline aluminosilicate ion exchange materials useful herein are available under the dssignations Zeolite A, 15 Zeolite B, Zeolite X, Zeolite HS and mixtures thereof. In an especially preferred embodimen~, the crystalline - - aluminosilicate ion exchange material is Zeolite A and has the formula Nal2[A102)12 (Si2~12J

20 wherein x is from about 20 to about 30, especially about 27.
Zeolite X of formula Na8~ t(Alo2)86~sio2~lo6] 276 H20 is also suitable, a~ well as Zeolite HS of formula 6 ~(A102)6(SiO2)6~ 7 5 H20)-Suitable nitrilotriacetic acid salts for use herein are 25 the trisodium and tripotassium ~alts of nitrilotriacetic acid. The acid itself or the disodium or dipotassium salts of the acid can also be used a3 additive. However, it will be under~tood that under t~e pH conditions typically encountered during manufacturing, the nitrilotriacetic acid 30 or salt will generally be converted into fully ionized form.
The nitrilotriacetic acid -~alt ~measured in trisodium form) constitutes from about 1% to about 8%, preferably from about 3~ to 7% by weight of composition. The percentage quantity (b) of nitrilotriacetic acid salt (again mea~ured in ~ ~7980~

trisodium form) and the percentage quantity (a) of aluminosilicate cation exchange material (measured in hydrated form) are such that the ~um a ~ 2b i8 between about 13 and about 27, pre~erably between about 14 and about 24, more preferably between about 16 and 21.
A further essential component of the compositions herein i8 from about 6% to about 14%, preferably from 8% to about 12% of a phosphate builder. The phospha~e builder is selected from sodium and potassium tripolyphosphates and hydrate~ thereof but is preferably substantially anhydrous or partly hydrated ~i.e. to no ~ore than about 60% of its hydration capacity). Phosphate builder content i~ mea~ured on an anhydrous ba~is however. Critically, the phosphate builder comprises le~s than about 12% thereof, preferably less than about 8~ thereof of pyrophosphates. Highly preferred is a phosphate builder system which is admixed in - dry crystalline form with the remainder of the detergent composition. - - -The detergent compositions of the invention also include a bleach system comprising an inorganic or organic peroxy bleaching agent, a heavy metal scavenging agent and in preferred compositions, an organic peroxy acid bleach precursor.
Suitable inorganic peroxygen bleaches include sodium perborate mono- and tetrahydrate, sodium percarbonate, sodi~m persilicate and urea-hydrogen pero~ide addition products and the clathrate 4NazSO4:2H202:1~aCl. Suitable organic bleaches include peroxylauric acid, peroxyoctanoic acid, peroxynonanoic acid, peroxydecanoic acid, diperoxydodecanedioic acid, diperoxyazelaic acid, mono- and diperoxyphthalic acid and mono- and diperoxyisophthalic acid. The bleaching agent i8 present in the compositions of the invention at a level of from a~out 5% to about 35%
preferably from about 10~ to about 25% by weight.
The heavy metal scavenging agent i8 preferably a water-soluble chelating agent. Preferred are aminopolyacids having four or more acidic proton~ per molecule. Suitable 980'1 chelating agents include a~inocarboxylate chelatin~ agents such as ethylenediaminetetraacetic acid (EDTA), hydroxyethylethylenediaminetriacetic acid (HEEDTA), dihydroxyethylethylenediaminediacetic acid (DHEEDDA), diethylenetriaminepentaacetic acid (DETPA), 1,2-diaminocyclohexane~N,N,N',N'-tetraacetic acid (DCTA) and water-~oluble salts thereof, and aminopolyphosphonate chelating agents such as ethylenediamine~etra(methylenephosphonic acid) (EDTMP), diethylenetriaminepenta(methylenephosphonic acid) (DETPMP), nitrilotri(methylenephosphonic acid) (NTMP),hexamethylenediaminetetramethylenephosphonic acid (HMTPM) and water-soluble salts thereof. The above water-soluble sequestrants are generally at a level of from about 0.05% to about 4% preferably fro~ about 0.1% to about 1.0% by weight.
The heavy metal scavenging agent herein can also be represented by water-soluble smectite-type clays selected from saponites, hectorites and sodium and calcium montmorillorites (sodium and calcium here designating the principal inorganic cation of the clay).
While any of the above smectite-type clays can be incorporated in the compositions of the invention, particularly preferred smectite-typ~e clays have ion-exchange capacities of at least SO meq/lOOg clay, more preferably at least 70 meq/lOOg (measured, for instance, as described in "The Chemistry and Physics of Clays", p.p. 264-265, Interscience (1979)). Especially preferred materials are as follows:~

Sodium Montmorillonite Brock Volclay BC
Gelwhite GP
Thixo-Jel Ben-A-Gel Imvite 1.,~ 380 Sodium Hectorite Veegum F
Laponite SP

Sodium Saponit~
Barasym NAS lO0 Calcium Montmorillonite ._____ Soft Clark Gelwhite L

Lithium Hectorite Barasym LIH 200 When present, the above clays are generally added at a level of from about 1% to about 20%, more preferably fro~
about 2% to about 10% by weight of composition. Such clays ~ also provide a ~abric softsning bene~it to the compositions.
Another suitable heavy metal scavenging agent is water-i~soluble, preferably colloidal magnesium silicate or a water-soluble magnesium salt forming magnesium silicate in the aqueous ~lurry crutcher mix prior to spray-drying. The ~agnesium silicate or salt is generally added at a level in the range from about 0.015% to about 0.2%, preferably from about 0.03% to about 0.15%, more preferably from about 0.05 to about 0.12% by weight (magnesium ba8i~. Suitable magnesium salts include magnesium sulfa~e, magnesium sulfate heptahydrate, ~agnesium chloride and magnesiu~ chloride hexahydrate.
The compositions of the inventio~ preferably al~o contain an organic peroxy acid bleach precursor at a level of fxom about 0.5% to about 10%, pre~erably from about l~ to about 6% by weight. Suitable bleach precursors are disclosed in UK-A-2040983, and include for example, the peracetic acid bleach precursors ~uch as tetraacetylethylanediamine, tetraacetylmethylenediamine, tetraacetylhexylenediamine, ~.2~9a~

~odium p-acetoxybenzene sulphonate, tetraacetylglycouril, pentaacetylglucose, octaacetyllactose, and methyl o-acetoxy ben~oateO Highly preferred bleach precursors, however, have the general for~ula II

~O
~-C-L IV

where~n R is an alkyl group containin~ from 6 to 12 carbon atoms whexein the longest linear alkyl chain extending from and including the carboxyl carbon contain~ from 5 to 10 carbon atoms and L is a leaving group, the conjug~te acid of which has a PKa in the range from 6 to 13.
The alkyl group, R, can be either linear or branched and, in preferrad embodiments, it contains ~rom 7 to 9 carbon atoms. Preferred leaving group~ L have a PKa in the range from about 7 - - ~
- 15 to about 11, more preferably from about 8 to about 10.
Examples of leaving groups are those having the formula (CH2 )xY

and b) p -N-C-R

y wherein Z is H, ~1 or halogen, Rl i9 an alkyl group having from 1 to 4 carbon atoms, x i8 0 or an integer of ~rom 1 to 4 and Y is selected from SO3M, OSO3M, CO2M, 3~30~

N (Rl)3Q and N (Rl)2-0 wherein M is H, alkali metal, alkaline earth metal, ammonium or substituted ammonium, and Q iR halide or metho~ulfate.
~he preferred leaving group L has the formula (a) in which Z is H, x is Q and Y i8 ~ulfonate, carboxylate or dimethylamine oxide radical. Highly preferred materials are sodium 3,5,5,-trimethylhexanoyloxybenzene sulfonate, sodium 3,5,5-trimethylhexanoyloxybenzoate, ~odium 2-ethylhexanoyl oxybenzenesulfonate, sodium nonanoyl oxybenzene sulfonate and sodium octanoyl oxybenzenesulfonate, the acyloxy group in each instance preferably being p-Qubstituted.
The bleach activator herein will normally be added in the form of particles comprising finely-divided bleach activator and a binder The binder is generally selected from nonionic surfactants such a the ethoxylated tallow alcohols, polyethylene glysols, anionic surfactant~, film forming -polymers, fatty acids and mixtures thereof. Highly preferred are nonionic surfactant binders, the bleach -activator being admixed with the binder and extruded in the form of elongated particles through a radial extruder as described in European Patent Application No. 62523.
Alternatively, the bleach activator particles can be prepared by spray drying as described in Bri~ish Patent Application No. 8422158.
The detergent compo~itions herein contain ~rom about 5~
to about 60%, preferably from about 8% to about 30~ by weight of an organic surfactant ~elected from anionic, nonionic, zwitterionic, ampholytic and cationic surfactants, and mixtures thereof. Surfactants useful herein are listed in US-A-4,222~905 and US-A-4,239,659.
The anionic surfactant can be any one or ~ore of the materials used conventionally in laundry detergent Suitable synthetic anionic surfactants are water-~oluble salts of alkyl benzene sulphonates, alkyl sulphate~, alkyl polyethoxy ether sulphate~, paraffin ~ulphonate~, alpha-olefin sulphonates, alpha-sulpho-~arboxylates and their ester~, alkyl glyceryl ethex ~ulphonates, fatty acid monoglyceride ~ulphates and sulphonates, alkyl phenol polyethoxy ether sulphates, 2-acyloxy alkane-l-sulphonate, and beta-alkyloxy alkane ~ulphonate.
A particularly suitable class of anionic surfactants includes water-soluble salts, particularly the alkali metal ammonium and alkanolammonium 9alt8 or organic sulphuric reaction products having in their molecular structure an alkyl or alkaryl group containing ~rom about 8 to about 22, especially from about 10 to about 20 carbon atoms and a sulphonic acid or ~ulphuric acid e~ter group. (Included in the term "alkyl" is the alkyl portion of acyl groups).
Examples of ~his group of synthetic detergents which form part of ths detergent compo itions of the present invention axe the ~odium and potassium alkyl sulphates, especially those obtained by sulphating the higher alcohols ~C8 1~) carbon atoms produced by reducing the glyceride~ of tallow or coconut oil and sodium and potassium-al-kyl benzene sulphonates, in which the alkyl group contains from about 9 to about 15, especially about 11 to about 13, carbon atoms, in straight chain or branched chain configuration, e.g. those of the type described in U~S-A- 2,2:20,099 and U.S-A-2,477,383 and those prepared from alkylbenzenes obtained by alkylation with straight chain chloroparaffins (using aluminium trichloride catalysis) or straight chain olefins (using hydrogen fluoride cataly~is). Especially valuable are linear straight chain alkyl benzene sulphonates in which the average of the alkyl group is about 11.8 carbon atoms, abbreviated as C11 8 ~AS, and C12 C15 Y
alkyl sulphates - Other anionic detergent compounds herein include the sodium C10 1~ alkyl glyceryl ether sulphonates, especially those ethers of higher alcohols derived from tallow and coconut oil; sodium coconut oil fatty acid monoglyceride sulphonates and 3ulphates; and sodium or potassiu~ salts o~
alkyl phenol ethylene oxide ether sulphat& containing about 1 7~30~

to about 10 units of ethylene oxide per molecule and wherein the alkyl groups contain about 8 to about 12 carbon atoms.
Other u~eful anionic detergent compounds herein include the water-soluble salts or esters of alpha-~ulphonated fatty acids containing from about 6 to 20 carbon a~om~ in the fatty acid group and from about 1 to 10 carbon atoms in the ester group; water-soluble salts of 2-acyloxy-alkane-1 sulphonic acids containing from about 2 to 9 carbon atoms in the acyl group and from about 9 to about 23 carbon atoms in the alkane moiety; alkyl ether ulphates containin~ from about 10 to 18, especially about 12 to 16, carbon atoms in the alkyl group and fro~ about 1 to 12, especially 1 ~o 6, more e~pecially 1 to 4 mole3 of ethylene o~ide; water-soluble salts of olefin sulphonates containing from about 12 to 24, preferably aout 14 ~o 16, carbon atoms, especially those made by reaction with sulphur trioxide followed by neutralization under conditions such that any sultones present are hydrolysed to the corresponding hydroxy alkane sulp~onates; water~soluble salts of paraffin sulphonates containing from about 8 to ~4, especially 14 to 18 carbon atoms, and beta-alkyloxy alkane sulphonates containing from about 1 to 3 carbon atoms in the alkyl group and from about 8 to 20 carbon atoms in the alkane moiety.
The alkane chains of the foregoing non-soap anionic surfactants can be derived from natural sources such as coconut oil or tallow, or can be made synthetically as for example using the Ziegler or Oxo processes. Water solubility can be achieved by using alkali metal, ammonium or alkanolammonium cationY; sodium is preferred. Suitable fatty acid soaps can be selected from the ordinary alkali metal (30dium, potassium~, ammonium, and alkylolammonium salts of higher fatty acids containing from about 8 to about 24, preferably from about 10 to about 22 and especially from about 16 to about 22 carbon atoms in the al~yl chain.
Suitable fatty acids can be obtained from natural sources such as, for instance, from soybean oil, castor oil~ tallow, ~.79~

whale and fish oil~, greaqe, lard and mixture~ thereof). The fatty acid~ al80 can be ~ynthetically prepared (e.g., by the oxidation of petroleu~, or by hydrogenation of carbon monoxide by the Fischer-Tropsch proces~). Resin acids are suitable ~uch as ro~in and those re~in acids in tall oil.
Napthenic acids are also ~uitable. Sodium and pota~sium 80ap~ can be made by direct saponification of the fat~ and oil~ or by the neutralization of the free fatty acid~ which are prepared in a separate manufacturing process.
Particularly useful are the sodium and potassium salts of the mixture3 of fatty acids derived from tallow and hydrogenated fish oil.
Mixtures of anionic surfactant~ axe particularly suitable herein, especially mi~tures of sulonate and sulfate surfactants in a weight ratio of from about 5:1 to about 1:5, preferably from about 5:1 to about lsl, more preferably from about 5:1 to about 1.5:1~ Especially preferred lS a mixtur-e of an alkyl benzene sulfonate having from 9 to 15, especially 11 to 13 carbon atoms in the alkyl radical, the cation being an alkali metal, preferably ~odium: and either an alkyl sulfate having from 10 to 20, preferably 12 to 18 carbon atomq in the alkyl radical or an ethoxy sulfate having from 10 to 20, preferably 10 to 16 carbon ato~s in the alkyl radical and an average degree of ethoxylation of 1 to 6, having an alkali metal cation, preferably sodium.
The nonionic surfactants useful in the present invention are condensates o ethylene oxide with a hydrophobic moiety to provide a surfactant having an average hydrophilic-lipophilic balance ~HL~) in the range from abaut 8 to 17, pre~erably from about 9.5 to 13.5, more preferably from about 10 to about 12.5. The hydrophobic moiety may be aliphatic or aromatic in nature and the length o~ the polyoxyethylene group which i8 condensed with any particular hydrophobic group can be readily adjusted to yield a water-~oluble compound having the desired degree of balance between hydrophilic and hydrophobic element~.

Examples of ~uitable nonionic ~urfactants include:
1. The polyethylene oxide condensate~ of alkyl phenol, e.g. the condensation products of alkyl phenols havlng an alkyl group containing from 6 to 12 carbon atoms in either a straight chain or branched chain configuration, with ethylene oxide, the ~aid ethylene oxide being present in amounts equal to 3 to 30, preferably 5 to 14 moles of ethylene oxide per mole of alkyl phenol. The alkyl substituent in such compourlds may be derived, for example, from polymerised propylene, di-isobutylene, octene and nonene. Other examples include d~decylphenol condensed with 9 moles of ethylene oxide per ~ole of phenol; dinonylphenol condensed with 11 moles of ethylene oxide per mole of phenol: nonylphenol and di-isooctylphenol condensed with 13 mole~ of ethylene oxide.
2. The conden~ation product of primary or secondary aliphatic alcohols having from 8 to 24 carbon atoms, in either ~traight chain or branched chain ~onfiguration, with from 2 to about 40 moles, preferably 2 to about 9 moles of ethylene oxicle per ~ole of alcohol. Preferably, the aliphatic alcohol comprise~ between 9 and 18 carbon atoms and is ethoxylated with between 2 and 9, de3irably between 3 and 8 moles of ethylene oxide per mole of aliphatic alcohol. The preferred ~urfactants are prepared from primary alcohols which are either linear (such as those derived from natural fat~ or, prepared by the Ziegler process fro~ ethylene, e.g~
myristyl, cetyl, ~tearyl alcohols), or partly branched such as the Lutensols, Dobanols and Neodolc which have abo~t 25 2-methyl branching (Luten~ol bei~g a TradeMark of BASF, Dobanol and Neodol being Trade Mnrks of Shell~, or Synperonics, which are understood to have about 50% 2-~ethyl b~anching (Synperonic i8 a Trade ~rk of I.C.I. ) or the primary alcohols having more than 50~ branched chain structure sold under the Trade ~ar~ Lial by Liquichimica.
Specific examples of nonionic sur~actants falling within the 3cope of the invention include Dobanol 45-4, Dobanol 45-7, Dobanol 45-9, Dobanol 91-2.5, Dobanol ~1-3, Dobanol 91-4, .,~i'~. i 798~

Dobanol 91-6, Dobanol 91-8, Dobanol 23-6.5, Synperonic 6, Synperonic 14, the condensation products of coconut alcohol with an average of between 5 and 12 moles of ethylene oxide per mole of alcohol, the coconut alkyl portion having from 10 to 14 carbon atoms, and the condensation products of tallow alcohol with an average of between 7 and 12 moles of ethylene oxide per mole of alcohol, the tallow portion comprising essentially between 16 and 22 carbon atoms. Secondary linear alkyl ethoxylates are al80 suitable in the present compositions, e-~pecially those ethoxylates of the Tergitol~
series having from about g to 15 carbon atoms in the alkyl group and up to about 11, e~pecially from about 3 to 9, ethoxy re~idues per molecule.
The compounds formed by conden~ing ethylene oxide with a hydrophobic base formed by the conden~ation of propylene oxide with propylene glycol. The molecular weight of the hydrophobic portion generally falls in the range of about 1500 to 1800. Such synthetic nonionic detergentQ are available on the market under the Trade Mark of "Pluronic"
supplied by Wyandotte Chemicals Corporation.
Especially preferred nonionic surfactants for use herein are the Cg-Cl5 primary alcohol etho~ylates containing 3-8 moles of ethylene oxide per mole of alcohol, particularly the C12-C15 primary alcohols containing 6-8 moles of ethylene oxide per mole o alcohol.
Cationic surfactants suitable for use herein include quaternary ammonium surfactants and surfactants of a semi-polar nature, for example amine oxides.
Suitable surfactants of the amine oxide class have the general formula V

R N - - (CH2)i l~ - R~ V
O O

~ ~79~30~

wherein R5 i8 a linear or branched alkyl or alkenyl group having 8 ~o 20 carbon atoms, each R6 i8 independently s~lected from Cl 4 alkyl and (CnH2nO)mH where i i~
an integer from 1 to 6, j i8 0 or 1, n is 2 or 3 and m i8 from 1 to 7, the sum total of CnH2nO groups in a molecule being no more than 7.
In a preferred embodiment ~5 has from 10 to 14 carbon atoms and each R6 is independently selected from methyl and -(CnH2nO)mH wherein m is from 1 to 3 and the sum total of CnH2~0 groups in a molecule i8 no more than 5, preferably no more than 3. In a highly preferred embodiment, j is O and each x6 is methyl, and R5 i5 C12-C14 alkyl.
- Another suitable class of amine oxid2 species i8 represented by bi~-amine oxides having the following substituents.

- R5: tallow C16-C18 alkyl; palmityl; oleyl; stearyl R6: hydroxye~hyl i : 2 o~ 3 A specific example of this preferred class of bis-amine oxides is: N-hydrogenated Cl~-Cl8 tallow alkyl N,N',N'tri-(2-hydroxyethyl) -propylene-1,3-diamine oxide.
Suitable quaternary ammonium su.r~actants for use in the present composition can be defined by the general formula YI:

R7- N+ - ~ (CH2)i ~l - R8 z VI

~ 17 -wherein R7 i~ a linear or branched alkyl, alkenyl or alkaryl group having 8 to 16 carbon atoms and each R8 is independently selected from Cl 4 alkyl, Cl 4 alkaryl and -(C~H2nO)m wherein i i~ an integer ~rom 1 to 6, j is 0 or 1, n i8 2 or 3 and m i8 from 1 to 7, the sum total of CnH2nO groups in a molecule being no more than 7, and wherein Z represents counteranion in number to give elec~rical neutrality.
ln a preferred embodiment, R7 has from 10 to 14 carbon atoms and each R is independently selected from methyl and (CnH2nO)mH wherein m is from 1 to 3 and the sum total of CnH2~0 groups in ~ molecule is no more than 5, preferably no more than 3. In a highly preferred embodiment j is 0, R is selected from methyl, hydroxyethyl and hydroxypropyl and R7 i8 C~2-C14 alkyl. Particularly preferred surfactants of this class include C12 alkyl trimethylammonium salts, C14 alkyltrimethylammonium salts, coconutalkyltrimethylammonium ~alt~, coconutalkyldimethyl-hydroxyethylammonium salts, coconutalkyldimethylhydroxy-propylammonium salts, and C12 alkyldihydroxyethylmethyl ammonium salts.
Another group of useful cationic compounds are the diammonium salts of formula VI in which j is 1, R is C12-C14 alkyl, each R8 is methyl, hydroxyethyl or hydroxypropyl and i is 2 or 3. In a particularly preferred sur~actant of this type, R is coconut alkyl, R is methyl and i is 3.
In highly preferred compositions, the builder system herein i8 supplemented by three additional components, polycarboxylate polymers, al~ali metal carbonates and alkali metal silicates.
The polycarboxylate polymers herein are pre~erably selected from co-polymeric polycarboxylic acids and their salts derived from an unsaturated polycarboxylic acid such as maleic acid, citraconic acid, itaconic acid or mesaconic acid as a ~irst ~onomer and ethylene, methylvinyl ether, acrylic ~798~0~L

acid or methacrylic acid a~ a second monomer, the copolymer compri~ing at lea~t ~bout 10 mole %, preferably at lea~t about 20 ~ole % of polycarboxylic acid units and having a weight-average molecular weight of at least about 12,000, preferably at least about 30,000; homopolyacrylates and homopolymethacrylates having a weight-averaye molecula~ weight of from abo~t 1000 to about 20,000, preferably from about 1000 to about lO,000; and mixtures thereof. Mixtures are highly preferred in the context of providing excellent bleach stability, detergency and anti-incrustation performance in the context of the low-phosphorous, low aluminosilicate/NTA
formulations disclosed herein. Suitable mixtures have a copolymer:homopolymer ratio of from about 1:2 to about 5~1, preferably from about 1:1 to about 5:1, more preferably about l:l to 2:1. The total level of polycarboxylate polymer in final product is preferably from about 0.5~ to about 5%, more preferably from about 2% to about 4~.
Weight-average polymer molecular weights can be determined herein by light scattering or by gel permeation chromotography using Waters ~Porasil (RTM) GPC 60 A2 and ~Bondagei (RTM) E-125, E-500 and E-1000 in ~erie~, temperature-controlled column~ at 40C against sodium polystyrene sulphonate polymer standards, available from Polymer Laboratories Ltd., Shropshire, UK, the polymer standards being calibrated as their sodium ~alts, and the eluant being 0.15M sodium dihydrogen phosphate and 0.02M
tetramethyl am~onium hydroxide at p~ 7.0 in 80/20 water/acetonitrile.
Alkali metal carbonate is i~portant herein fo~ providing the appropriate in-use Rolution pH for optimum detergency (rom about pH lO to pH ll, preferably from about pH 10.4 to about pH 10~6, measured as 1% ~olution). Generally, the compo~itions of the invention include ~rom about 5% to about 30~, prefer~bly from a~out 10% to about 25% alk~li metal ~arbonat~ (anhydrou~ basi~). Alkali metal silicate i8 pre~erably included in the compositions of the invention at a level in the range ~rom about 1% to about 4%, more preferably ~'7~3~30~ .

from about 1.5~ to about 2.5%. At lower levels, bleaching performance iB found to be increasingly degraded; at higher levels, on the other hand, aluminosilicate performance and fabric appearance is detrimentally effected by aluminosilicate particle aggregation.
The compositions of the invention can be supplemented by all manner of detergent and laundering components, inclusive of suds suppressors, enzymes, fluorescers, photoactivators, bleach catalysts, soil su pe~ding agents, anti-caking agents, pigments, perfumes, fabric conditioning agents etc.
Suds suppressors are represented by materials of the silicone, wax, vegetable and hydrocarbon oil and phosphate ester varieties. Suitable silicone suds controlling agents include polydimethylsiloxanes having a molecular weight in the range from about 200 to about 200,000 and a kinematic viscosity in the range from about 20 to about 2,000,000 mm2/s, preferably from about 3000 to about 30,000 mm /s, and mixtures of siloxanes and hydrophobic siianated (prefera~ly tri~ethylsilanated) silica having a particle size in the range from about 10 millimicrons to a~out 20 millimicrons and a specific surface area above about 50 m2/g. Suitable waxes include microcrystalline waxes having a melting point in the range from a~out 65C to about 100C, a molecular weight in the range from about 400-1000, and a penetration value of at least 6, measured at 77F by ASTM-D1321, and also paraffin waxes, synthetic waxes and natural waxes. Suitable phosphate esters include mono-and/or di-C16-C2~ alkyl or alkenyl phosphate esters, and the corresponding mono- and/or di alkyl or alkenyl ethe phosphates containing up to 6 ethoxy groups per molecule.
Enzymes suitable for use herein include those discussed in US-A-3,519,570 and US-A-3,533,139 to McCarty and McCarty et al issued July 7, 1970 and January 5, 1971, respectively.
Suitable fluorescers include Blankophor MBBH (Bayer AG) and Tinopal CBS and EMS (Ciba Geigy). Photoactivators are discus~ed in EP-A-57088, highly preferred material~ being * - Trade Mark 980~L

zinc phthalocyanine tri- and tetra--sulfonates. S~itable fabric conditioning agents include di C12-C24 alkyl or alkenyl amines and ammonium and quaternary ammonium salt3.
Suitable bleach catalysts are discussed in European Patent Application No. 72166 and European Paten~ Application No.
84302774.9.
Antiredeposition and 50il suspension agents suitable herein include cellulose derivatives 6uch as methylcellulose, carboxymethylcellulose and hydroxyethylcelluloRe.
The compositions of the invention are preferably prepared by spray-drying an aqueous slurry comprising the aluminosilicate and, where present, alkali metal silicate and anionic surfactant. The nitrilotriacetate can also be spray-dried or added separately to the spray-dried base granules. Tripolyphosphate builder and, where present, carbonate, are also separately dry mixed with the spray-dried base granules. The aqueous slurry is mixed at a temperature -in the range from about 45-~0C and the water-content of the slurry adjusted to a range of about 25~ to about 50%.
Spray drying is undertaken with a drying gas inlet temperature of from about 250-390 C, preferably about 275-350C, providing a final moisture content in the range of from about 8% to 14% by weight.
In the Examples which follow, the abbreviations used have the following designations:-C12LAS ; Sodium linear Cl~ benzene sulphonate TAS : Sodium tallow alcohol sulphate C12/14AS : C12/14 alcohol sulphate, sodium salt TAEn : Hardened tallow alcohol ethoxylated with n moles of ethylene oxide per mole of alcohol C12TMAB : C12 alkyl trimethyl ammonium bromide *

~obanol 45E7 : A C14_1s primary alcohol condensed with 7 molefi of ethylene oxide.
35 TAED : Tetraacetyl ethylene diamine PAG : Penta acetyl gluco~e AOBS : Sodium p-acetoxy benzene sulphonate * - Trade Mark 1~

~æ~s~

NOBS : Sodium nonanoyl oxybenzenesulphonate INOBS : Sodium 3,5,5 trimethyl hexanoyl oxybenzene sulphonate INOBA : Sodium 3,5,5 ~rimethyl hexanoyl oxybenzene carboxylate EHOBS : Sodium 2-ethyl hexanoyl oxybenzene sulphonate Silicate : Sodium silicate having an SiO2:Na20 ratio of 1:6 Sulphate . Anhydrou~ sodium sulphate Carbonate : Anhydrous sodium carbonate CMG : Sodium carbo~ymethyl cellulose Silicone : Comprising 0.14 parts by weight of an 85:15 by weight mi~ture o~ ~ilanated silica and silicone, granulated with 1.3 ~arts of sodium tripolyphosphate, - - and 0.56 parts of tallow alcohol - condensed with 25 molar proportions of - ethylene-oxide NTA : Sodium nitrilotriacetate PCl : Copolymer of 3:7 maleic/acrylic acid, average mol~cular weight about 70,000, as sodium salt PC2 : Polyacrylic acid, average molecular weight about 4,500, as sodium salt Phosphate : ~nhydrous pentasodium tripolyphosphate (or tho/pyro content = 3%) Perborate : Sodium perborate tetrahydrate of nominal formula NaB02.3H20.H202 . Enzyme : Protease EDTA : Sodium ethylene diamine tetra acetate - 22 - ~79~0~
.
Briyhtener : Di~odium 4,4'obis~2-morpholino-4-anilino-s-triazin-6~ylamino) 8~ ene-2:2'-di~ulphonate DETPMP : Diethylene triamine penta(methylene pho~phonic acid), marketed by Monsanto under the Trade name Deque~t 2060 EDTMP ~ Ethylenedia~ine t~tra (methylene phosphonic acid), marXeted by Monsanto, under the Trade name Dequest Clay : Sodium mont~orillonite Examples I to VIII
Granular de~er~en~ compositions are prepar~d as follows.
A base powder compo~ition i8 first prepared by mixing all components except Dobanol 45E7, bleach, bleach activator, enzyme, ~uds suppre~sor, phoæphate and carbonat~ in a crutcher as an aqueous slurry at a temperature of about 55C
and containing about 35% water. The 61urry is then spray drled at a gas inlet temperature of about 330C to form base 2-0 powder granules. The bleach activator, where present, is then admixed with TAE25 as binder and extruded in the f-orm of elongate particles through a radial extruder as described in European Patent Application Number 62523. The bleach activator noodles, bleach, enzyme, suds suppres~or, phosphate and carbonate are then dry-mi~ed with the base powder composition and finally Dobanol 45E:7 i~ ~prayed in~o the final mixture.

EXAMPLES

I II III IV V VI VII VII~
.

~AS - 3 3 - 4 - - -C12/14As 5 8 - 4 1 4 TAE25 0.5 0.5 0.8 0.3 0.8 0.8 0.2 TAEll - 1 - _ 0.6 - _ 1 Dobanol 45E7 2 - 4 2 4 8 10 5 C12TM~B 2 3 - _ _ 2 2 NOBS 3 - - _ _ _ _ ~'~'7 ~3 EXAMPLES (cont'd.) PAG ~ 4 AOBS
Perborate 25 20 10 24 20 18 24 28 EDTMP - 0.3 0.3 - - - 1.0 DETPMP 0.4 - - - 0.5 - - 0.1 EDTA 0.2 0.2 0.2 0.1 0.3 0.1 0.2 0.3 Clay - - - 6 - 4 - -Magnesium (ppm) - 1000 750 - - - - 800 PCl 1.5 2 2 2 1 3 2.5 PC2 0.5 1 - 0.5 1 ~ 0.5 2 Zeolite A* 9 8 12 6 13 8 9 14 Pho~phate 10 8 9 -12 7- 8 9 Soap 1-- - 2 - 3 3 2 Carbonate 8 18 10 8 5 13 6 11 Silicate 1.5 2 2 :L 7 2 2.5 1.5 Silicone 0.2 0.2- 0.3 0.2 0.2 0.4 0.5 0.2 Enzyme 0.1 0.5 0.~ 0.3 0.4 0.5 0.7 1.0 Brightener 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Sulphate, Moi~ture ~
Miscellaneous --------------------- To 100 -------------------- -* Zeolite A of 4 A pore size.

The above co~positions are low phosphate detergent compo~itions di~playing excellent bleach stability, fabric c~re and detergency performance across the range of wash temperatures with particularly outstaAd~ns performance in the case of Example~ I to IV on greasy and particulate 80il8 at low wash temperatures.

Claims (14)

1. A granular detergent composition characterised by:
(a) from about 6% to about 18% by weight of a water-insoluble aluminosilicate cation exchange material, (b) from about 1% to about 8% of an alkali metal salt of nitrilotriacetic acid, (c) from about 6% to about 14% of phosphate builder, the phosphate builder being selected from sodium and potassium tripolyphosphates and comprising less than about 12% thereof of pyrophosphate, (d) from about 5% to about 35% of inorganic or organic peroxy bleaching agent, (e) from 0% to about 10% of organic peroxy acid bleach precursor, and (f) a heavy metal scavenging agent, wherein the percentage quantities of (a) + 2(b) is between about 13 and about 27.

2. A composition according to claim 1 wherein the quantities of (a) + 2(b) is between about 14 and about 24.

3. A composition according to claim 1 comprising from about 7% to about 16%, water-soluble aluminosilicate cation exchange material.

4. A composition according to claim 1 wherein the quantities of (a) + 2(b) is between about 16 and about 21.

5. A composition according to claim 1 comprising from about 8% to about 14% water-soluble aluminosilicate cation exchange material.

6. A composition according to claim 1, 2 or 3 wherein the cation-exchange material has the general formula I
Mz[(AlO2)z (SiO2)y)] x H2O I
wherein M is a calcium-exchange cation, z and y are at least 6; the molar ratio of z to y is in the range from about 1.0 to about 0.5; and x is from about 10 to about 264; the aluminosilicate having a calcium ion exchange capacity of at least 200 milligrams equivalent of CaCO3/gram, a calcium ion exchange rate of at least about 2 grains of Ca2+/gallon/minute/gram/gallon, and a particle size diameter of from about 0.1 microns to about 10 microns.

7. A composition according to claim 1, 2 or 3 comprising from about 3% to about 7% of the nitrilotriacetic acid salt.

8. A composition according to claim 1, 2 or 3 comprising from about 8% to about 12% of the phosphate builder and wherein the phosphate builder comprises less than about 8% thereof of pyrophosphate.

9. A composition according to claim 1, 2 or 3 comprising at least 0.5% organic peroxy acid bleach precursor.

10. A composition according to claim 1, 2 or 3 comprising at least 0.5% organic peroxy acid bleach precursor and wherein the organic peroxy acid bleach precursor has the general formula II
II

wherein R is an alkyl group containing from 6 to 12 carbon atoms wherein the longest linear alkyl chain extending from and including the carboxyl carbon contains from 5 to 10 carbon atoms and L is a leaving group, the conjugate acid of which has a pKa in the range from 6 to 13.

11. A composition according to claim 1, 2 or 3 wherein the heavy metal scavening agent is selected from water-soluble aminopolycarboxylates and aminopoly-phosphonates having at least four acidic protons per molecule or a water-insoluble smectite-type clay selected from saponites, hectorites and sodium and calcium montmorillonites.

12. A composition according to claim 1, 2 or 3 additionally comprising from about 0.5% to about 5% of a polycarboxylate polymer.

13. A composition according to claim 1, 2 or 3 additionally comprising from about 0.5% to about 5% of alkali metal silicate.

14. A composition according to claim 1, 2 or 3 comprising from about 5% to about 60% of organic surfactant selected from anionic, nonionic, zwitterionic, ampholytic and cationic surfactants and mixtures thereof.