AU1007699A - Maleic acid-based aqueous cleaning compositions and methods of using same - Google Patents

Description

I

AUSTRALIA

Pateis Ac.t COMPLETE SPECIFICATION (OR1G)NAL) Class It. Class Application Number: Lodged, Complete Specification Lodged, A.,cccpied: Publi,,hed- 'Priority Jlated Art, Name of Applicant: The Procter Gamble Company Actual Inventor(s).

Michel jean Carri Ax. Koenig Eddy Vos.

Addres for Service.

IP Australia C 0 Batch~ Nw

A

ft ~ftft*Sft ft PHILIS ORMONDE FiTZPATRICK Patent and bade Mark Attorney)s 367 Collin Street Melbourne 3000 AUSTRALIA Invention Title: MALEIC ACU)-BASEI) AQUJEOUS CLEANING COMPOSITIONS AND METHODS OF USING SAME Our Ref 56650 POE Code: 44135144135 The folwn statemenut Is a N11i dmflrptlon of this invention, iududir4 the bet metbof e pedrfoig it known to appicant(s)., MALEIC ACID-BASED AQUEOUS CLEANING CONIPOSITIONS ANC, ME-AoDS OF USING SAME4.

This: application is a divisional of Austr~lk'an Pate~nt Application 73 6 31 95 t-he conterits uf which are' herein incorporaed by reference.

Technca LqeLdS The present invention relates to cleaning compositions for hard-surf aces. More spe%iflz.ally coaposititms are described which give optimal performance in removing limescale stainsa and encrustation* while ensuring appropriate surface safety, especially when used for cleaning and descaling metal surfaces.

Tap water contains a celtain aftount of solubilized 'ions which upon water evapration eventually deposlz as salts suach an calcium carbonate on surfaces which are often in contact with maid water,.- resulting in an unaesthetic aspect of said surfaces. This limescale formetion and deposition plienc~mtnm is even more acute in places wherwater in particularly hard.

it is well known In the art that lirescale can be removed chemically with acidic solutions. and a great variety of acidic cleaning campositions have been described for this Purpose.

2 t4-.wmver, in many instancesaii cornpositions may cajs th robe tha-9 W a64ds which are used damage th97 surfaces en rae.I pariCL~lr~ 5 0 .nisairxing m~ay occur when metal surfzces such a~ auminumchroed teelo tiness steei are treated with such ~would therefore be desirable to obviate this issue in providing a cleaning comnpor$$:-4 for the remorv-al of lmscae. said composito pose~$l§a superdor imescale removing, caaiy Whlbeng losf to metal _surfaces.

It h.&s n,6v been f ound that t or an ac~id which has a first p~a not exceeding s, surClac* safety is improved without comprouising on linescals renovizq capacity by Combiniflg said acid or mixtures thereof with malaic acid, in .3t appropriate ratios. Indeed, it has been fo~n that the compositions of the present inven~tion comprising maleic acid and such an acid in appropriate ratios are significantly safer to metal surfal,.as than the same compositionls without &&aic acid, wihile being also particularly effective in removing limescale.

AA~ &dVantaqe of this inventionl is that said compositions are also safe to other surfaces besides metal surfaces inldn synthetic surfaces.

US-3 277 005 -disclosex solid capoitio1"5 suitable for 25 use with water to fora aqueous solutions for descaliflq the internal metal surfaces of the jacket of the glasslined jacketed equipment. Said compositiols to -s a cleaning agent such as sialfawic or hyrdrochloric acid, maleic acid and a corrosion~ inhibitor. Surf actants are not disclosed.

DE-23 822 658 jsclos-s composititons uSefu. for remOv.itig oxide lavers Zro metal sArtaces like copper or bnz-- Said compositions comprise a mineral acid for example nitric acid, a cartboxylic -acid such as maleic acid, pkhosphoflic acid an'd thicureas. Nonionic surfactants are disclosed as opi.onal i gradients without specifying appropriate amuounlts.

EP-A-O 496 lag discloses, a exposition comprisingq noniOflic surfactants toga-.Aar with maleic acid w~naraby good limescale removal is provided. Citric acid is disclosed together with rAleiC azid in some ell the exanples. But citric acid is not effective in rez-oving lisescaiC at low'PH.

SuM"=r of the invntion The present invae1tiofl is an aqueous cleaning composition having a pHl of from 0.1 to 4.5. suitable for removing limescale froe hard-surfaces. comprisingq from 0.01% to by weight of the total compositionk of a surf actant or nixtures thereof. 2 aleic acid and an acid which has a first p7A& not exceeding 5. with the vaxception of citric acid, or mixtures thereof, in a weight ratio of inaleic acid to said acid such that surface safety is improved.

The present iantfttn also encoapasses a process of trealaq har-sufac" esecilly metal surf aces.

~30 wherein &coUPOsition. according to the present invention is used in its neat-or diluted fos 3a The Present inventiori thus provides a Composition according to any one of the claims 1 to 8 wherein said acid is selcte fromn the group $1f Subfmkc hyrochloric, nitri, formic, methanesutonic and phosphoric acid& Throughout the description and ciaims of thisr specjication, the word -comprise& arnd variations Of the Word, such as 'comprising' and 'compris-es*. is not initended to exclude other additives or components or integers.

Delai ed Decrittion of the Invention The compositions accrding to the present invention are designe for removing iimestcale or soils comprisiN limescale as an essential componet_ tu tLe ops as a first. essential ingredient an acid whch has a airst p~a not: exceeding 5 or mixt,,res thereof Peterably. the acids to be used herein ud-ich are par-;cuiarlv e f ficient to remove linescale on.- many surfaces, have their Uirst p14A not exceeding 4, more Preferab.y not exceedin4; 3 and most preferably below Z. According to the present ivention said acids can be Organic or inorganic acids.

Examples of inorganic acids are sulfamic acid pac2' I hydrochloric acid nitric acid phozphoric acid and metharftsuIf onic acid (PKAul.9). AA~ example of organic acid is f arm ic acid Preferredi for use herein is sulfamic 4acjc alone or in aixtujre with anothjer acd Futeuo- h cozPcsitiOns according to the Present invenrtion are free of citric acid which does not perform very well as a linescal. remover at pH1 below 2. The cupositions of the present invention typically comprise from 0 1 to 20% by weight of the totat composition of an acid which has a -first pKa niot exceeding 5 cz 20 miktures thereof, referabty from 0.1% to 10% and mre prefierably frem 01% to The couposftons according to te present invention furhef comprie rmleic acid as the Second essential ingredient The cornpositions according to the present inventfion 4tpical comprise* from 0. 1% to Sby weight of the toWa composition of inakei aWi, preferably ftom I% to and nme preferabty fromn 8% to 20%. This percentage is calculated on the basis of the molecular weight of ft acid fom, but bInaleic anhydride is equally convenient for use in fte cornpsifia accordinq to the present inventior, Indeed rnaleic anhydride is, generlly cheape and it is transform-ed into the adid for(M when. rincoroted in an aqueous medim It has been observed tha surface safety is knpmM~x WeN treafiNg meftl sufaces with the C Itons of the presen~t inventiOn comprising maleic, id and an. acid having its first p-ra not exceeding 5. an. appropriate weight ratio of one to the other. Said ratio is dependent on the specific acid used and thus is different for each~ acid or each mixture thereof. Acordiag to the present invention the weight ratio of zalftic acid to said acid is such that the surface safety is improved.

sy nsurface safety isproveflent"m it is to be untderstood N~ that less damage to the surface treated is observed with the compesitionS of the present invention compared to the same coapositions without aaleic acid, this at a given time of contact. M(ore specifically, we have observed that by plotting the surface damage against the aaeunt of malsic. in any qiven composition cwepr1iin an acid having its first pKa not exceeding S, a curve is obtained which comprises a stop (see fig. l. The surface safety is Oimproved- wnen the step is reached preferably half the stop and more preferably the whole of the step A method suitable for measuring surface safety is a visual grading method mentioned hereinafter in the examples. said surface safety test method is reported in the literature in )34S1 124.1-130.

In a preferr~ed embodiment of the present invention. the a~positions herein comprise sulfamic acid as said acid having its first p~a not exceeding 5. pref erably said ceoitiom' comprise from 0 5% to 5% by weight at the tota! compos it in of said sujlfaaic, acid with a weighxt ratio of maleic- acid to said sultaxic aci.d of from 15:1 to 3zi, preferably of from 8:1 to 4:1 Ttke c=mpositioin5 according to- the presnent invention have a pxMozfr 0.1 to S pr. rably offro01 t anld mno" ureferably of from 0,5 2.

:.zi IM the 541t CCmpriSe as a further essential ingte-d1ieflt a sr~ or mixvturiS thr~ The ccvQ-it in accardir.lg to the. present invntion cCuprise f~v b weght Of the total COm sit ion~ at said or xtueSthereof, more preferably 0,5 to mirxureserbly rcm 0 1 to S% and ost prefer-biT 0.11 to it, &11 typeS of surfact&nts z&Y be' useid i presnt j~tfli~ jcludnq onic. anionic, a~.r1 mphoteric or z:vttriOnic surf actaflts- t~sa possible to Use aixtures of suc surfactanltswihu depati.ng froa the spirit of. the present invotntleft.

suitable nonioni1c surf &ct&nts to Le used ,herein axre I~alkaxylated alcohol noojoniC sutfact&flts which can be readily sade by condensation PrvCeSS 5 v'i .Ch are idel XrTV3%m in the art Howikver. a great variet'y Of such lkoxylated alcohols. espcilly *thoylted and/or ~poylated al-oftaks is xlso conveniently coamral!Y available. Surfactants, catalogs are available which list a number of surf actatits jinclingfl nanonif~cs.

hcoordingly. preferred alkoxylateCk alcohols for U!Sft herein are noniortic surfat-ants, acotdiftq ta the formula z 15 RO(EWCPIP 1 where R is a hydrocarbont chain of free I to z4 carbon~ atows, K is ethylene aside n is propylr, oxide. and a and V~wikL repreS*flt the averaqe deree of.

respectively athorylatio .xmd propaxylat.-o' are of frow 0 to 24_ -Me hvdtophbbiC Moiety of the ~n~nnc compound '3D can be a primary or secondry. atrajqht or branched alcohol bavinq trom I to 24 carbon atows..Prfre nonionic sa.?t&ctanta for use in the composit~i* according to the invntiok are the conetnsAto' prafuts of ethYlW oxide with alcohols havivi9 a stxaiktkt alkyl chain, bawU'" fr& 6 t* 22 carbonk atmft. whereint thek deqrQOec &f a oYl&tilon is fro& I. to IS, prefeably fro* to 12. Su&ch sgjtable nonioiic surfactmtz are co~orcially av.-ciable sheLL zlcr instancet. underth.* trade nazt Dotac~lR Or frCg Sh~te' iuvc te-,Z raze Luteaso!R- Tblese n-ionics are preferred 'ocluze they have tbeen founrd to allow the formulation of a stable product '.iZttcut reqairiflq the addition of stabiliz~ers or hydrotopes. When using othier noenionic., it may be nec.Ssary to add hydrztopes suach as cuzenw sulptcen~te or solvents suc-h as b%%tyldijllether.

I .suitable amionic surfactan~ts for USe h.-ain ar~e aC4Q-4nq to the t.OrZU'd R 1

ISG

3 K wteren R, represents a hydrocarbo~n grou~p selected from the group. consist irq of straiqht or branched *lkyl radicals contairting from 6 to 24 carboft atoms And &lkY! phony! radicals containinq trva 6 to 15 carbon atoas in the alkyl qrcikp. M is a salt forming cation whdch typically is salectod from thei g-c~ap c=%sistipg of sodium. potassium, anmut and mixtiur*1 thereof.

ZO other suitable anionic- surtactants can be represented by the water-solubl* salt* of an, alkyl sulfate or An alkyl polyathasylate ether sulfate wtherstn the alkyl gromp Cota in* trm to 24 carbon atems, And preferably trom I to 30 othoXY greups for the alkyl Polyethoxy late ether %1 ~f at**.

saitable catilonic surf actants to be used hereint include *-derivatives -of quaftary Amonium. pkMoapMMiua.

4iwiiazoibs and. suln4'Aun cmouds. freferred cationic ,tCtnts for use herei are according to the foraula

RIX

2 1tR45 X- Whereinl X is a Counteraftia. R is a bqldroC rOn tat and Ia. R3utR a .Ap~~n selected fro& I or CX-C4 hydrocarbon chains.. Xn a preferred amod5Sft at the. present inxv ntian. ftI is a C12 y' hydOcarbmf Chi tPrferably C14. Ci or CIS &V R2, R-3 abd 1 4 Are All three Metthyl, "An X is halgen prferblybromide or clride. most preferably rCi xqt- -S Q STAB c L t r I s to a aM~-;LMkcQZidt ICA~ and (,rstAHl trz-yi amea broside I~AS) suta v1 ittaI-On ic Surfactamts cofltdlZ bqn cat;Qicic and aua1Chy rOrhil.ic %rcus on the SA= M-2lc ,e at a r.1ti~~fvidt r~eof Plit- rtL* typical. catzn7mc qt-oup is a t~.trry aznrnOIIux grzp, alhoq other ICcharge*d groups iik Phosphafium3. iaidzc!W a~ suitonXu1 qr,,Iup$ can be Used- The typic&l anion-C.

grup &e cartaylates 4xv-4 sxi±*tonates.

although other gaups like sulf~atos, pho-sphonates. arr~ th* 'Lke can be US 2& A qene.ric form-ula fa soe preferred zvitterioflic v~rfctahts is R11 4 (RZI (R 3 )RAX7 wherein R, i s a hydrophobic group.: RZ a nd P- are each nc,4 a1zy1.: hydrazy alkyl ox ather substituated alkyl group wich CAMs Aao b* IoinWA to tars ring strctures with the 4; R4 ir, a A*ety jzirtinq the cat ion-c nixrqtr& atoa to the hydrophilic qro~aP ind is tYPicallY an alkYlere.

hydroxy alkylene, or palyalkoxy g~roi.p catainil4 .0row toa A carbon atoms; and X is the Lpilic qz~p which is Preferably al carbQ*~ylate or Sulf Onate qrQUP.

tkfxt yoraphabic qz* are &Ilkvl qrMuPS rUR 4 to 22. ]P~r"IralY 1*ees than IS. Slra p~~tesby lssthn I cAz# atoms The .hydrphobi~c 3C0 roW Cant Contain Uaasturat-ic anf or sibatitUats aredeo )invXiiq qroupS such to &ryI 9traa. amido qroups. ester *qrur and the like- li generAl. the SiSPIO 6141l gx=Ps aepxrx&=* for =ast az4 stab.lt reasns.

3S Othor specti jc vixterianic Aurf ACtantS. hAvQ th* "mWeIc rermz~s!"- -cantaining froxa urp to ZQ. prefrab1~r up 'to 18, mr preferably up to 16 carhn-n atos, *acb. is eiter- a hrogen (when attached to the aa-Ido nitxzcq~r'. short chain alky! or substituted alkyl containing IrCM WIe to 4 carbarL ateas, preferably 'groups S&lected xrom tAe gzoup 0 cosisting eft methyl. ethyl. propyl, hydroxy substituted ethyl Or propyl and mixtures thereof, prtferab.y methyl, each Ra is selected from the group ecorsistittg a-c txydroqn-n and hydroxy groups ad each n is a number from 1 to 4, preferably from 2 to 3e uo preterably with no th~ane.o hydroxy group in any 3 soiety- The RX qrcups can be branched ad/r unsaturated. The R grous can also be connected to torm ring structuzes.

su~rfactant of tbis type is a CXQ-C.1 fatty acyamcloroyla. hyd yropr~ne)sufobtanethat is available fromt the Sherex Company under th* trade Rame avarion CALS sulabfobtaift.te.

S'aitabl* asphaoric siarfactant are surf actants uwhich are Similar to the zvitterioai surfactants bu~t withouat the 2Sqkatrrary qroaip. However. tbey- Cota in an 2ane group that is protonated at the loV PH 40t the cuPosition ta form cationic g~roup and they may also Possess an anionie group at these pffs.

23( Int one emodimt of the prement. invention Wnere it is *desirable to give sam viscosity to the Compositions of the presment invention the wfactant i'S A miXtUre Of I nonioac surf actant, as 4*scribw hoeinkefore together *with~ a Cationic surf actant. as .Iescrribed hereinbwf ore C itions comwise front 0.5% t 5 y ogto the total co=vosition of said mixtur, of Surf actant.

The compositions according to the present invention are aqueous, Accordingly, the compositions according to the present invention comprise from l0% to 95% by wei~ht of the total composition of water, preferably from 50% to 90t. most preferably from 70% to The compositions according to the present invention may further comprise a variety of other ingredients including perfumes, colorants, bactericide, thickeners, dyes, chelants, pigments, solvents, stabilizers, corrosion inhibitors and the like, In one embodiment, the compositions of the prevent invention are free of corrosion inhibitors, i.e.

JS compounds which have the sale purpose of inhibiting corrosion.

The compositions according to the present invention are particularly suitable for treating metal surfaces which 20 can be found in a kitchen or in a bathroom. Indeed, the compositions of the present invention exhibit good livescale removing properties for both the kitchen-type stains and the bathrooa-type stains, i.e. f or stains which contain not only calcium carbonate but also soap scum and/or grease.

The compositions according to the present invention are also suitable for treating metal surfaces which can be found in appliances such as for example irons, coffee ~.30 machines or kettles. The compositions to be used in the application of descaling appliances preferably contain low levels of suarfactants, preferably below It by weight of the total composition and move preferably tram 0.1% to in the application of desceling appliances it is 35 preferred to use the cationic surf actants described %lt Mq heweinbefore as the surfactant, The present invention further encompasses a process of treating hard-surfaces, especi.ally metal surfaces, wherein a composition as hereinbafore defined is dispensed in its neat form from a container onto said surf aces, then left to act onto said surfaces and then removed by rinsing. Said process can be used both for treating metal surfaces found in bathrooms, kitchen* or appliances.

The present invention further encompasses a process oi treating hard-surfaces, especially metal surfaces, wherein a composition as hereinbefore defined is used in diluted form. The expression "Weed in diluted form" herein includes dilution by the user, which occurs for instance in the application of descaling appliances.

Typical dilution levels are of from 0.5% to 50% of the compositions. The compsitions herein are also particularly suitable to be used in hot conditions, e.g.

when descaling a coffee machine said compositions can be used diluted and in hot conditions (406C to 1404C).

An used, in t~ foregoing, paragraphs, the expression *treating" may include washing as the compositions 9* ~according to the present invention comprise surf actants 25 and removing limescale while improving surface safety due to the appropriate combination of acids of the present invention.

lb. present invent ion is further illustrated -by, the 30 following experimental data and examples.

The surface safety of solutions comprising 3% of sulfamiic acid (pI~a-0.1) toqether with increasing percentaqes of maleic acid is evaluated by the following surface safety test method.

The surface safety test method is conducted. on an aluminium surf ace. A drop of the solution to be tested in put onto said surface and left there for 14 hours. In this test the drop of the solution is left to dry at room temperature (206). At the end of the exposure time.-txie surface is rinsed with soft water and wiped dry. The same surfaca without any treatment is taken as a reference. The comparison between the surface treated and untreated is done visually using the following grading scalez o no visual surface damage 1 slight surface changel damage; weak staining 2 slightly more surface damage; medium staining S3 late of surface damage; strong staining.

*As a result the curve in Figure I was obtained reporting 25 the visual surface damage against the increase of the percentage-ct maleic acid by weight of a total solution comprising 3% of sultamic acid.

noe curve in figure I shows that surfae safety is improved when maleic acid and sultamic acid &ae present In appropriate ratios of one to the other.

urter xamlesofcompositions according to the present invention are the following. Those coepositions are made comprisinq the listed ingredienlts in the listed (weight Tngrj4tQDtS% by Weight) 1 2.

4 KaIsic &aid Sultfamic acid N~itric acid ForsiC acid, Lu'Lexsal &O7* Cetyl trisetjhy1 ammonius brcaidea* water* minors

UPI

to 100 S S

S

S.

S

S

-I

S

Exposure (hours) 33 5 17 24 34 *Lutensol K07 a non ionic SUrtaCtltt Cetyl trimethyl aUMIi' bromide surfactan~t.

in a cationlic The -surface safety test gethod described here inbef ore has been conducted for compositions I to 51* on~ an &1IMIntip surf ace and a stainless steel surface vith an 30 e43"are of different time period as indicated hesi?'bofere. ySo visual difference has be"n found for the compositions 1 to 5 when coparing the surfaces treated with the rgfetmwe surf ace (untreated). in other words, these cegpogitiolIU are sae to both the aluminlium 35 a"d stainless Steel Surfaces.

Furthersore no dazage to an aluaminium~ or a staness steel surf ace has been observed when conducting the surface safety test method in hot conditions,~ i.e.

bowling point temperature of the compositions testeo, with compositions 4 and 5 for an exposure period time of hours.

ft

C

I

zs 300

Claims (11)

1. An aqueous cleaning cornp4ositiofl having a pH o from 0.1 to 4.5. suitable for removing imiesca le deposits on hard-surfaces, comprising from 0,01% to by weight of the total composition of a surfactant or mixures thereof and maleic acid, wherein said composition further comprises an acid which has a first pKa not exceeding 5, with the exception of citric acid, or mixtures thereof. 41 a weight ratio of maleic acid to said acid such that surface safety is improved,

2. A composition according to claim 1 wherein the surfactant is selected from the group of nonionic. anionic, cationic, zwitterionic. amphateric surfactants or mixtures thereof. 1. A composition according to any one of the preceding claims comprising from 01% to 45% by weight of the total compositio M of malei acid.

4. A compositiont accord"n to claim 3 comprisin from I% to 25% by weight of the total cormosiion of rnaleic acid, 5, A composition according to claim 3 coniprisi frm 8 to 20% by weight of the total compositiork of maliaic: acid

6. A CoonfiOrbkf according to any one of fth preceding claims comnprising from 0. 1% to 20% by weight of the total compositionS of an acid which has a first pl~a not exceedin 5. or mixtures thereof. A corrposi on accoding to claim 6 wherein said acid or mi~fture thereof is present in an uimount of horn 0.1 to 20% by weight of fth WWta cmposition.

8. A cWVposiion accuding to claim 6 wherein said acid or mixtures themef is preet in an amnout of from 0.1 to 5% by weight of the total w~osition, 9, A composition acording to any one of the precedig ciaim wherein sai acid has a first pKa not exceeding 4. A composition according to claim 9 wherein said acdd has a first. pKa not exceeding 3,

11. A composition according to claim 9 wherein said acid has a first pKa of below 2.

12.- A compositon according to any one of the claims 1 to 8 wherein said acid is selected from the group of suffamic,, hydrochloic- nitric, formi. methanesutfonic and phosphoric acicfs. 13 Acomposinaccrding toclarn I or car 2 whreinsaid aid is sufamic acid and wherein said composition comprises from 0.5% to 5% by witht of the Mtoa composition of said sutfamic acid and wherein the weight ratio of maleic acid tosaid acid isoffkrnm15.1 to 3:1-

14- A composition according to claim 13 wherein the Weiht ratio ot maleic acid to said acid is from8:1 to 41 A comnpositon accordirr to any one of the preceding claim wherein the surfactant is a nonionic surfactant which is a oondensation product of ethylene oxide with an alcoWol said alcohol having a staight WOI chain comnprisng from 6 to 22 carbon Am, said condensation product haiiing a degree of etoiyation of from I to 15 or mixtures thereof

18- A convosition accordirg to claim 15 wherein said condensation product has adegree of el lalationof fom 5to 12. 17. A CompOSitio according to amy one V. the clamsm 1 to 7 wheein #We surfactant is a cationtc, surfactant accordig to the formula RRR 3 4 N* X7, wherein X is a couriteraniori, R, is a hydrocarbon chain and Rf3 and R, are independently selecte from H or G 1 -C 4 hydrocarbon chains. 18- A compositon according to any one of thve claims I to 7 wherein the surfactant is a mixtu~re of a nonionic.-:uifactant with a cationic surfactant according to the formuta R 1 R 2 R 3 R 1 N* X7, wherei-n X is a counteranion, R, is a C-- hydrocarbon chain and R3 and F 4 are independently selected from H or hydrocarbon chairns. .19, A conmition according to any one of the preceding claimns wherein the pH- is from 0.1 to 3. A composition according to claimn 19 wherein the pH is ftom 0,5S to 2.

21.. A process of treating hard-surfaces, preferabty metal surfaces, *herein a. composition according to any one of fth preceding claiims Ls disKped in its nee, form from a container or trsed in a diluted form onto id surfaces,. then kleft to act onto said surfaces and then rerroved by rinsing, thereby ioV~oving surface safely-

22. An aqueous clearting corr sition having a pH of fmicn 0. 1 to according to clam i. substantia~y as herefibetore desczted walh referenc to any of the examnples. 2-3- A process of treating hard surfaces accofding to ciaiT. 21, substanfialy as herenefr descrbe. DATED: 11 Jmaay 199 ORMONQE FITZPA'TRtCK Aftorneys ficx THE PRtOCTER AGAMLE COMPANY