CA2203134A1 - Detergent composition - Google Patents

Abstract

A detergent composition is disclosed which comprises a surfactant selected from anionic, nonionic, cationic, amphoteric and zwitteronic detergent-active compounds and mixtures thereof; a detergency builder comprising zeolite P having a silicon to aluminium ratio not greater than 1.33 (zeolite MAP); and a cellulytic enzyme. Preferably the zeolite MAP has a particle size (d50) of < 1.0 micrometre.

Description

W O96/12781 PCTrUS95/13212 DETERGENT COMPOSITION

The present invention relates to a detergent composition and, in particular, to improvements in the detergency ~rullllance of laundry detergent compositions comprising zeolites as a sequest~ring agent for water hardness.
Delergellt compositions for heavy-duty fabric washing conve-ntion~lly contain detergency builders which lower the concentration of c~lci~-m and m~gn~Sillm water hardness ions in the wash liquor and thereby provide good detergency effect in both hard and soft water.
Conventionally, inorganic phosphates, such as sodium tripolyphosphate, have been used as builders for laundry del~l~ellt~. More recently, alkali metal aluminosilir~te ion-eYch~ngers, particularly crystalline sodium aluminosilicate zeolite A, have ~een proposed as repl~eem~nt~ for the inorganic phosph~te~.
For example, EP 21 491A (Procter & Gamble) discloses detergent compositions conl~ ing a building system which includes zeolite A, X or P (B) or a l"i~lure thereof. EP 384070A (Unilever) discloses specific zeolite P m~t~ri~l~ having an especially low silicon to ~ll..,.;n;ll... ratio not greater than 1.33 (he~ei~ t;l referred to as zeolite MAP) and describes its use as a detergency builder. To date, however, zeolite A is the prefelled aluminosili~te detergency builder in commercially available products.
It is also known in the art that d~ler~ent formulations containing small particle W O96/12781 PCT~US95/13212 size zeolites can have advantages over other zeolites in processing of the surfactant, due to the increased surface area of absorption. For example EPA 0521635 t (Unilever) discloses a free-flowing particulate detergent composition including zeolite MAP which preferably has a particle size dso (defined hereinafter) within the range of from 0.4 to 2.0 micrometres and most preferably from 0.4 to 1.0 micrometres.
The quantity "dso" in~1ic~tes that 50 wt% of the particles have a ~ met~.r smaller than that figure. EPA 0522726, EPA 0552053 and EPA 00552054 (IJnilever) also all disclose a ~refelu ce for zeolite MAP having a small average particle size and illustrate detergent compositions in which the zeolite MAP has a particle size (dso) of 0.8.
We have found, however, that formulations cont~ining small particle size zeolites (dso < 1.0 micrometres) show a ~ignifi~nt increase in fabric encrustation after repeated washing as co"lp~d with coarser size zeolites (dso > 1.0 micrometres).
We have surprisingly found that superior detergency effects can be achieved by incol~ ting in the dele~ellt composition a cellulytic enzyme.
D~gent compositions conti.ining c~ cPs and are known in the art. By using such enzymes in a delel~ellt, it is possible to hydrolyze the celluloses present in stains and soil on the clothes, to such a degree that they become readily soluble in water.
The use of a cellulytic enzyme has benefits in the laundry process, in particular with depilling, clay removal and in achieving a whiter a~ ce. We have found that the use of zeolite MAP with a cellulytic enzyme leads to ~ignifi~nt ol."~lce benefits particularly in boilwash encru~t~tinn According to a particular aspect of this invention we have found that particularadvantages accrue in using a cellulytic enzyme in a delel~ellt composition comprising small particle size zeolite MAP such as zeolite MAP having a particle size dso of <
1.0 mic~",eL~e. In particular, the problem of fabric encrustation after repeatedwashing is reduced or elimin~ted by means o~ the present invention.
Thus, the present invention provides a del~l~;ellt composition comrri~ing:
a) a sllrf~ct~nt s-,l~t~ from anionic, nonionic, cationic, amphoteric and ~ 'ViUtl ;oniC detergent - active compounds and mixtures thereof;
b) a detergency builder compri~ing zeolite P having a silicon to ~ ini ratio not greater than 1.33 (zeolite MAP); and c) a cellulytic enzyme.
The cellulytic enzymes usable in the present invention generally have a molecular weight range of 20kD to 70kD and include both bacterial and fungal -W O96/12781 PCTrUS95/13212 cellulytic enzymes. Preferably, they will have a pH optimum of between 5 and 9.5.
Suitable cellulases are disclosed in U.S. Patent 4,435,307, Barbesgoard et al, issued March 6, 1984, which ~icclos~Ps fungal cellulase produced from Humicola insolens and Humicola strain DSM1800 or a celhll~e 212-producing fungus belonging to the genus Aeromonas, and cellulase extracted from the hepatopancreas of a marine mollusk (Dolabella Auricula Solander). Suitable cellulases are also disclosed in GB-A-2,075,028; GB-A-2,095,275 and DE-OS-2,247,832.
The enzyme may be incorporated in the granular composition in an amount, for example, of 0.01 to 4% by weight, preferably 0.05 to 2% by weight, most preferably 0.1 to 0.2% by weight at an activity of 1000 cevu/g, to provide respectively 10 to 4000, 50 to 2000 and 100 to 200 cevu per 100 g of composition.
Examples of specific commercially available catalytic enzymes suitable for use in the present invention include Carezyme and Endolase.
Fndol~e A, for example, may be inco~ ated in the granular detergent composition in an amount of 0.1 to 3% by weight, preferably 0.5 to 2% by weight at an activity of 1250 cevu/g.
In liquid detergent forrn~ tion~ typical PY~mples of suitable amounts for the cellulytic enzymes are 0.09% of cPlhll~e at 3000 cevu/g and 0.08% of F.n~iol~ce A at 5000 cevu/g.
The detergent col.lposition according to the invention contains, as an essentialingredient, one or more surf~t~nt~ SPl~P~t~P~ from anionic, nonionic, cationic, amphoteric and ;~ ;t nic de~e ~ent-active compounds and Illi~Luies thereof. Suchsurf~ct~nts are well known and descrihed in the lil~ldlufe, for example, in "Surface-Active Agents and De~e~p~nt~", Volumes I and II by Schwartz, Perry and Berch.
F~mrlPs of suitable anionic sllrf~t~nt~ include alkylbenzene sulphonates, particularly sodium linear alkylbenzene sulphon~tes having an alkyl chain length of Cg-Cls; C12-Cls primary aLkyl sulphates; olefin sulphonates; alkyl xylene sulphonates; dialkyl sulphosucçi~ s; and fatty acid ester sulphonates. Sodium salts are generally pl~fc~lled.
F.Y~mrlPs of suitable nonionic s--rfact~nt~ include alkoxylated adducts of fatt,v alcohols co~ ining an average of from 3 to 10 alkylene oxide groups per molecule.
Preferred alkoxylated ~-lduct~ of fatty alcohols contain an average of less than S
alkylene oxide groups per molecule, for es~mrle less than 4 alkylene oxide groups per molecule e.g. 3.5 and usefully 3 alkylene oxide groups per molecule or less and usefully also greater than 0.5, or 1, or 2 alkylene oxide groups per molecule.
A particularly ~l~fe.l~d aliphatic alcohol ethoxylate is a primary alcohol having an average of 12 to 15 carbon atoms in the alkyl chain conden~ed with an average of three ethoxy groups per mole of alcohol.
Specific examples of suitable alkoxylated adducts of fatty alcohols are SynL~lullic A3 (ex ICI), which is a C13-Cls alcohol with about three ethylene oxide groups per molecule and Empilan KB3 (ex Marchon), which is lauric alcohol 3EO.
Another class of nonionic surfactants comprises alkyl polyglucoside compounds of general formula RO(CnH2nO)tzx wherein Z is a moiety derived from glucose; R is a saturated hydrophobic alkyl group that contains from 12 to 18 carbon atoms; t is from 0 to 10 and n is 2 or 3; x is from 1.1 to 4, the compounds incl~lrling less than 10% unreacted fatty alcohol and less than 50% short chain alkyl polyglucosides. Compounds of this type and their use in detergent compositions are disclosed in EP-B 0070074, 0070077, 0075996 and 0094118.
The surfactant will generally be included in the deLt;.~ellt composition in an amount of 5 to 60% by weight, preferably 5 to 40% by weight and most preferably from 10 to 25% by weight of the composition.
According to the present invention the detergency builder system is based on zeolite MAP, optionally in conjunction with one or more supplennent~ry builders.The amount of zeolite MAP employed may range, for example, from 5 to 60 wt%, more preferably from 15 to 40 wt%.
Zeolite MAP is described in EP 384070A (Unilever). It is defined as an aLkali metal alumino-silicate of the zeolite P type having a silicon to aluminil-m ratio not greater than 1.33, ~ref~l~bly within the range from 0.9 to 1.33 and more preferably within the range of from 0.9 to 1.2.
Of particular interest is zeolite MAP having a silicon to ~ minillm ratio not greater than 1.15 and, more particularly, not greater than 1.07.
Zeolite P having a Si:Al ratio of 1.33 or less may be prepared by the following steps:
(i) mixing together a sodium ~1umin~te having a mole ratio NA20:A1203 within the range of from 1.4 to 2.0 and a sodium silicate having a mole ratio SiO2:Na20 within the range of from 0.8 to 3.4 with vigorous stirring at a l~ dture within the range of from 25 C to boiling point usually 95 C, to give a gel having the following co~ osition;
A1203:: (1.75-3.5) SiO2: (2.3-7.5) Na20 :P (80-450)H20;
(ii) ageing the gel cull,posilion for 0.5 to 10 hours, preferably 2 to 5 hours, at W O96/12781 PCTrUS95/13212 S

a lem~ldtUre within the range of from 70 C to boiling point, usually to 95 C, with sufficiçnt stirring to m~in~in any solids present in suspension;
(iii) separating the crystalline sodium aluminosilicate thus formed, washing to a pH within the range of from 10 to 12.5, and drying, preferably at a te"lpe-dture not excee~ling 150 C, to a moisture content of not less than 5 wt%.
Preferred drying methods are spray-drying and flash drying. It al~peals that oven drying at too high a te,l,~,dture may adversely affect the calcium binding capacity of the product under certain circum~t~nces.
Commercial sodium met~cili~tto pentahydrate dissolved in water and commercial sodium silicate solution (waterglass) are both suitable silica sources for the production of zeolite P in acco~ance with the invention. The reactants may be added together in any order either rapidly or slowly. Rapid addition at ambient te"~.dlu.e, and slow addition at elevated le",pe-dture (90-95 C) both give the desired product.
Vigorous stirring of the gel during the addition of the reactants, and at least moderate stirring during the subsequent ageing step, however, appear to be es~nti~l for the formation of pure zeolite P. In the absence of stirring, various mixtures of crystalline and amorphous m~teri~l~ may be obtained.
Zeolite MAP generally has a c~lcium binding capacity of at least 150 mg CaO
per g of anhydrous alumino~ ~te, as meadsured by the standard method described in GB 1473201 (Henkel). The calcium binding capacity is normally 160 mg CaO/g and may be as high 170 mg CaO/g.
Although zeolite MAP like other zeolites contains water of hydration, for the purposes of the present invention amounts and percentages of zeolite are eAl,ressed in terms of the notional anhydrous m~teri~l. The amount of water present in hydrated zeolite MAP at ambient ~nl~ldlure and humidity is generally about 20 wt%.
A particularly p-tr~ d æolite MAP for use according to the present invention has a dso of < 1.0 micrometre, for example 0.4 to 1.0 micrometres.
The particle size is determined by conventional analytical techniques such as, for example, microscopic dt;le~ ination lltili~ing a sc~nning electron microscope or by means of a laser granulometer.
Zeolite MAP having the required small particle siæ according to one aspect of the present invention can be plc~p~ed by the conventional techniques as described above while adopting one or more of the following steps:-a) increasing cryst~llic~hQn ~ll~ldlllre and re~llring cryst~lli~tiQn time.
b) increasing the size of the seed crystals used to produce the æolite;
c) feeding the aluminosilicate gels into the cryst~lli~tion stage imme~i~tely after W O96/12781 PCTrUS95/13212 they form (i.e. elimin~te ageing of gels);
d) screening the zeolite product to remove fine m~tt~ri~l.
According to one embodiment of the invention the zeolite MAP detergent builder is in powder form.
For convenience in h~n~lling, however, the material may be granulated by conventional techniques such as spray drying or by a non-tower method to form larger particles.
In the granular detergent compositions according to the invention, the detergency builder can be zeolite MAP alone or a combination of zeolite MAP withan organic or inorganic cobuilder.
Suitable organic cobuilders can be monomeric or polymeric carboxylates such as citrates or polymers of acrylic, meth~rylic and/or maleic acids in neutralised form. Suitable inorganic cobuilders include carbonates, and amorphous and crystalline l~mPll~r sodium ~ilic~tes Suitable crystalline l~mP.ll~r ~ tes have the composition:

NaMSix02x+l, YH20 where M is sodium or hydrogen, preferably sodium; x is a number from 1.9 to 4; and y is a number from 0 to 20. Such m~teri~l~ are described in US Patents No.
4664839; No. 4728443 and No. 4820439 (Hoechst AG). F~peci~lly pl~felred are compounds in which x = 2 and y = O. The synthetic m~t~ri~l is commercially available from Hoechst AG as S-Na2 Si20s (SKS6) and is described in US Patent No.
4664830.
The total amount of detergency builder in the granular composition ranges from 10 to 80 wt%, more preferably 10 to 45 wt%.
De~ent con-l)o~;t;on~ according to the invention may also suitably contain a bleach system. This preferably compri~s one or more peroxy bleach compounds, forexample, inorganic persalts or organic peroxyacids, which may be employed in conjunction with bleach plC~;UlSOl~i to improve ble~hing action at low ~ res.
The bleach system preferably comprises a peroxy bleach co---po~ d, preferably an inorganic persalt, optionally in conjunction with a precursor. Suitable persalts include sodium perborate monohydrate tetrahydrate and sodium percarbonate, with sodium pe~ l,onate being most l.r~felr~d.
Preferred bleach yl~;w~1S are peracetic acid pr~ul~l~, such as tetr~etylethylene ~ mine ~AED); and peroxybenzoic acid precursors, such as sodium benzoyloxybenzene sulphonate (BOBS) W O96/12781 PCTrUS9S/13212 Other m~tt-ri~l~ which may be present in the detergent compositions of the invention include, for example, fluorescel~, antiredeposition agents, inorganic salts such as sodium sulphate, other enzymes, lather control agents, fabric softening agents, pigm~nt~, coloured speckles and perfumes.
The detergent compositions of the invention may be prepar~d by any suitable method. The particulate deter~ent compositions are suitably pr~ared by any tower(spray-drying) or non-tower process.
In processes based around a spray-drying tower, a base powder is first p.~)ared by spray-drying a slurry and then other col"pollents ln~ t~ble for processing via the slurry can be sprayed on or admixed (post-dosed). The enzyme will generally be post-dosed.
The zeolite MAP is suitable for inclusion in the slurry, although it may be advantageous for proces~ing reasons for part of the zeolite MAP to be inco.~,~ted post-tower. The l~mt~ r silicate, where this is employed, is also post-dosed.
Al~l"ati~rely, particulate detergent co"lpositions in accordance with the invention may be pl~ared by wholly non-tower processes such as granulation.
The granular de~e~gellt compositions of the invention may be pl~aled to any suitable bulk density. The co"lposilions preferably have a bulk density of at least 400 g/l preferably at least 550 g/l, most preferably at least 700 g/l and, with particular plefer~nce at least 800 g/l.
The benefits of the present invention are particularly evident in powders of high buL~c density, for example, of 700 g/l or above. Such powders may be ~r~ared either by post-tower den~ifi(~tiQn of spray-dried powder, or by wholly non-towermethods such as dry mixing and gr~mll~tion; in both cases a high-speed mixer/gr~n~ tQr may advantageously be used. Plocesses using high-speed mixer/gran--l~tors are ~ s~cl, for eY~mple, in EP340 013A, EP 367 339A, EP 390251A and EP 420 317A (Unilever).
According to a further aspect of the invention there is provided a liquid dele,g~nl composition, preferably a heavy duty liquid delel~;ent composition comprising a surfactant as previously described, a detergency builder comprisingzeolite MAP and a cellulytic enzyme.
According to this embo lim~nt the liquid delt;l~ent composition may be of any convenient physical form which may be aqueous or anhydrous. The term "liquid"
used herein includes pasty viscous formulations such as gels. The liquid detergent system compri~es, as the detergency builder zeolite MAP optionally in combination with other detergency builders such as fatty acids, citric acid or zeolite A.
A pl~felled co-builder is a l~m~ r sodium silicate such as SKS-6 which is W O96/12781 PCTrUS95/13212 particularly useful in pasty viscous formulations such as gels or in non-aqueous liquid de~t;,ge~ such as those described in WO92/16608 (Henkel).
The liquid detergent composition generally has a pH of from 6.5 to 10.5.
The total amount of detergency builder in the liquid composition is preferably from 5 to 70% of the total liquid composition.
The invention is illllstMted by the following Example in which the abbreviations have the mP~ning~ defined below.
AS : Sodium alkyl sulphate E05 : C14-Cls primary aliphatic ethoxylate alcohol having an average of 5 ethoxy groups per mole of alcohol.
Soap : tallow soap.
TAED: Tetr~cetyl ethylene ~i~minP.
DETPMP : Diethylene triamine penta (methylene phosphonic acid), m~rlcPted by Monsanto under the Trade Name Dequest 2060.
MA/AA : Copolymer of 1:4 maleic/acrylic acid (Mw 80,000).
Citrate: Trisodium citrate dihydrate.
Antifoam granules : Mi~ture of ~ n~t~ silica: silicone in ratio of 1:1.5 (M Wt 100,000).

Examplçs Particulate co",pollents and co~"positions were plc~alcd as follows:

Anionic surfactant AS (C12-15) 9 - -AS (C12-14) - 9 9 Nonionic surfactantE05 7 7 9 Soap - - 3 Zeolite MAP (anhydrous) 20 20 30 Sodium Carbonate 13 6 13 Sodium Bicarbonate 0 0 5 Amorphous sodium silicate 3 0 3 Crystalline sodium silicate 0 10 0 Citrate 2 0 5 Sodium Percarbonate 18 24 0 TAED granules 10 4 0 DETPMP 0.5 0.3 0.4 Anlifoa", gran~ s 2 2 2 Enzyme ~Jr~nlll~s 2 2 2 Carezyme (1000 cevu/g) 0.15 0.20 0.10 F.nrlol~e (5000 cevutg) 0.20 0.30 Moi.~tllre/Mi~.ll~n~us b~l~nce b~l~nce balance (Soil release agents, fabric wl.i~ -g agents, perfumes, water) -W O96/12781 PCTrUS95/13212 The following Examples and Reference Examples demonstrate the reduced fabric encrustation after a repeated wash cycle of the detergent composition according to the invention Ref 1 Ref 2 Ref3 Example4 Example 5 Surfactant 14% 14% 14% 14% 14%

Zeolite A 35% 0% 0% 0% O~i (d50 = 3 microns) Micronised zeolite A 0% 35% 0% 35% 0%
(dso = 1 micron) Zeolite MAP 0% 0% 35% 0% 35%
(dso = micron) C~c; y~eatlOOO 0% 0% 0% 1% 1%
cevu/g Fabric ash 1.0% 2.0% 2.0% 1.0% 1.0%
(25 cycle washing)

Claims (10)

WHAT IS CLAIMED IS:

1. A detergent composition comprising:
(a) a surfactant selected from anionic, nonionic, cationic, amphoteric and zwitterionic detergent - active compounds and mixtures thereof;
(b) a detergency builder comprising zeolite P having a silicon to aluminium ratio not greater than 1.33 (zeolite MAP); and (c) a cellulytic enzyme.

2. A detergent composition according to claim 1, wherein the zeolite MAP has a particle size (d50) of < 1.0 micrometre.

3. A detergent composition according to claim 2, wherein the zeolite MAP has a particle size (d50) of 0.4 to 1.0 micrometre.

4. A detergent composition according to any one of claims 1 to 3, wherein the zeolite MAP has a silicon to aluminium ratio not greater than 1.15.

5. A detergent composition according to claim 4, wherein the zeolite MAP has a silicon to aluminium ratio not greater than 1.07.

6. A detergent composition according to any one of claims 1 to 5, which comprises from 5 to 80% by weight of zeolite MAP.

7. A detergent composition according to any one of claims 1 to 6, which comprises the cellulytic enzyme in an amount to provide from 10 to 4000 cevu per 100 g of composition.

8. A granular detergent composition according to any of claim 1 to 7, which comprises from 5 to 60 wt % of component (a); from 10 to 80 wt% of component (b)and a cellulytic enzyme (c) in an amount to provide from 50 to 2000 cevu per 100 g of composition.

9. A liquid detergent composition according to any of claims 1 to 7 which comprises from 5 to 60 wt% of component (a); from 5 to 40 wt% of component (b);
and a cellulytic enzyme (c) in an amount to provide from 100 to 200 cevu per 100 g of composition.

10. A detergent composition according to any one of claims 1 to 9, which comprises the cellulytic enzyme in an amount to provide from 10 to 4000 cevu per 100 g of composition.