Cleaning and surface conditioning of formed metal surfaces

WO 96/19553 PCT/US95/16014 CLEANIMG AND SURFACE CONDITIONING OF FORMED HETAL SURFACES CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of copending application Serial No. 126,143 filed September 23,1993, which was a continuation of Application Serial No. 910,483 filed July 8,1992 and now abandoned, which was a continu- s ation-in-part of copending application Serial No. 785,635 filed October 31, 1991 and now abandoned, which was a continuation of application Serial No. 521,219 filed May 8,1990, now U.S. Patent No. 5,080,814, which was a continuation of application Serial No. 395,620 filed August 18,1989, now U.S. Patent No. 4,944, io 1987, now U.S. Patent No. 4,859,351. The entire disclosures of all the afore¬ mentioned patents, to the extent not inconsistent with any explicit statement herein are hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION Field of the Invention « This invention relates to a cleaner and surface conditioner for formed met¬ al surfaces, and particularly, to such a lubricant and surface conditioner which improves the mobility of aluminum cms without adversely affecting the adhesion of paints or lacquers applied thereto, and also enables lowering the dryoff oven temperature required for drying said surfaces. Still more particularly, this inven- mtHtiUlM i fi niiitiiiim*' W09fi/i95S3 PCT/US95/16014 fiJsey2Si2riofBelate!i "ecen,,, en.ronmen,a, consider ! ron,an,inan,S ,he Panged in fte «„, (e(i to an J ?*" "* " * Averages *« and „*,*„,. However ,1 ' C'eanin9,0 rem sue -.ndntia,ratesofit:::rTumcans™-- * •» can. For example, optimu ™ * *• »** s *»*. surface on the inside 2 "**",0 a"ain a" *-*Mn * -OPM ,0 convey „. cat s ' -" « -eninttealumi„tefltere'«'P«er, ,3 linven.in SePra<toona«ona, -9 can ™n J '""-sed ..oducti demand is "W cans per „ of time. FdrTT ',0 " .bepassedthroJIen, of surface *« 11«> cans per 'JT iS 0n ,he a - to---cm8p:;;-:-suchrat8bei„ y surfeee 'w«hnett and thus have imiiMmmmiim pCTrtJS95/16014 WO 96/19553 uv,w0rc the flow of cans through Su«,pnrter n»sfe««ngp (spoilage, aucson occur in addition to hflh rateso, .

the, consideration ,n modtng ft. w» affect aWotmactobapHnteden *-*-*-;:0Sr« aeLace. in sUch a case, fte face, and lacquers may be sprayed o a.Hesionc,*- P-* - "ng indusU, is directed ln addiUon, *e cunant Uend ,n *e can n dovmugmg o.

toward using mtnner gauges o, -™%1B in that, a«er was, inum c metal s«»* has cd a pMJ „, ing, fte cans rehire a lower drying «£•££ lowe th9 drying oven umn suength pressure quality -W •* they reached lhe .emperaturer.uttedinfteca printing station, and caused * « . the ..y m*««—*-**«*» 6printerst0,n«eas8 production, re- „ aluminum cans through smgle fliers an p auce M iammis, minimize do '-• of washed can, Ac- aown, and erble leering fte dry,ng pe .itisanoofftisW-u „„«, o, aluminum cans and to ««-££ „ leas, tor large w the most widely used current ««"»*" , succession c six waning .d rinsing operaUo „ Tab,e A1S sometimes —««—*-SSncalledaibule-tothenumbered used also; when used, th.s stage stages.) s - <—- •.,«**J** *« - - ..KMfc tolfikWM&v* _ imWAft- « -vs, -j,..- WO 96/19553 PCT/US95/16014 Aqueous Acid ?""* Surfactant Cleaning Tap Water Rinse Mild Acid Postcleaning, Conversion Coating, or Tap Water Rinse Tap Water Rinse Deionized ("Dn Water Rinse, It is currently possible to produce a can which is satisfactorily mobile and to which subsequently applied inks and/or lacquers have adequate adhesion by using suitabie surfactants either in Stage 4 or Stage 6 as noted above. Preferred treatments for use in Stage 4 as described above have been developed and are described in U. S. Patents 5,030,323 and 5,064,500. With these treatments, a metallic element (not necessarily or even usually in elemental form) is incorpor¬ ated into the lubricant and surface conditioning layer formed.

Experience with prolonged practical use of lubricant and surface cond«m er forming treatments that incorporate metal into the surface conditioner layer formed has revealed that they are susceptible to the development of at Mt one separate impurity phase, commonly called "sludge" or some similar term, Vm sludge is usually sticky, so that small particles of it easily adhere to the contain¬ ers being treated, and if they do so can cause an undesirable phenomenon called "metal exposure", a failure of the subsequently applied interior sanitary lacquer to completely isolate the beverage product contained in the aluminum can from contact with the metal can body. Therefore, if a sufficient amount of sludge forms, it must be removed before continuing with can condition.ng. Be- cause of the tackiness of the sludge, it is difficult to remove satisfactorily, so that minimmng and, if possible, preventing formation of the sludge is one of the ob- jects of this invention.

—»-»»J,-,w»,..„T-T,1-,l-11[l.,Tl..f|f ,-11,-. .--n rfll - '-iriiiiniifiriiri '•* _ PCT/US95/16014 WO 96/19553 pFgf-.RrPTtQN OF THF INVENTION Other than in the claims and the operating examples, or where otherwise expressly indicated, all numbers expressing quantities of ingredients or reaction conditions used herein are to be understood as modified in all instances by the > term "about" in describing the broadest scope of the invention. Practice within the numerical limits given, however, is generally preferred. Also, unless other- wise specified, all descriptions of components of compositions by percentages, "parts", or the like refer to weight or mass of the component compared mm the total, o In accordance with this invention, it has been found that a lubricant and surface conditioner applied to aluminum cans after washing enhances their mo¬ bility and, in a preferred embodiment, improves their water film drainage and evaporation characteristics as to enable lowering the temperature of a drying oven by from about 2S* to about 100° F without having any adverse effect on the is label printing process. The lubricant and surface conditioner reduces the coeffi¬ cient of static friction on the outside surface of the cans, enabling a substantial increase in production line speeds, and in addition, provides a noticeable im¬ provement in the rate of water film drainage and evaporation resulting in savings due to lower energy demands while meeting quality control requirement?.

More particularly, in accordance with one preferred embodiment of this in¬ vention, it has been found that application of a thin organic film to the outside sur¬ face of aluminum cans serves as a lubricant inducing thereto a lower coefficient of static friction, which consequently provides an improved mobility to the cans, and also increases the rate at which the cans may be dried and still pass the quality control column strength pressure test. It has also been found that the de¬ gree of improved mobility and drying rate of the cans depends on the thickness or amount of the organic film, and on the chemical nature of the material applied to the cans.

The lubricant and surface conditioner for aluminum cans in accordance with this invention may, for example, be selected from water-soluble alkoxylated surfactants such as organic phosphate esters; alcohols; fatty acids including mono-, dh trK and poly-adds; My acid derivatives such as salts, hydroxy acids, S *i -\ fit I PCT/US95/16014 WO 96/19553 amides, esters, ethers and derivatives thereof; and mixtures thereof.

The lubricant and surface conditioner for aluminum cans in accordance with this invention in one embodiment preferably comprises a water-soluble de¬ rivative of a saturated fatty acid such as an ethoxylated stearic acid or an eth- s oxylated isostearic acid, or alkali metal salts thereof such as polyoxyethylated stearate and polyoxyethylated isostearate. Alternatively, the lubricant and sur¬ face conditioner for aluminum cans may comprise a water-soluble alcohol having at least about 4 carbon atoms and may contain up to about 50 moles of ethylene oxide. Excellent results have been obtained when the alcohol comprises poly- io oxyethylated oleyl alcohol containing an average of about 20 moles of ethylene oxide per mole of alcohol.

In another preferred aspect of this invention, the organic material em¬ ployed to form a film on an aluminum can following alkaline or acid cleaning 'and prior to the last drying of the exterior surface prior to conveying comprises a is water-soluble organic material selected from a phosphate ester, an alcohol, fatty acids including mono-, di-, tri-, and poly-acids fatty acid derivates deluding salts, hydroxy acids, amides, alcohols, esters, ethers and derivatives thereof and mix¬ tures thereof. Such organic material is preferably part of an aqueous solution comprising water-soluble organic material suitable for forming a film on the clean- zo ed aluminum can to provide the surface after drying with a coefficiciit of static friction not more than 1.6 and that is less than would be obtained on a can sur¬ face of the same type without such film coating.

In one embodiment of the invention, water solubility can be imparted to organic materials by alkoxylation. preferably ethoxylation, propoxylation or mix- zs ture thereof. However, non-alkoxylated phosphate esters are also useful in the present invention, especially free add containing or neutralized mono-and diest- ers of phosphoric acid with various alcohols. Specific examples include Tryfac® 5573 Phosphate Ester, a free add containing ester available from Henkel Corp.; and Triton® H-5S. Trten® H-66, and Triton® QS-44, all available from Union so Carbide Corporation.

Preferred non-ethoxylated alcohols indude the following classes of al¬ cohols:

- -* ,,-w .mrr*-* Ifi ;;,,i_u_ •rfw. W09d/19553 l*d/V»3-'.»/AVv*'» - — * T5 Suitable monohydric alcohols and their esters with inorganic acids include water soluble compounds containing from 3 to about 20 carbons oer molecule.

Specific examples include sodium lauryl sulfates such as Duponol® WAQ and Duponol® QC and Duponol® WA and Duponol® C available from Witeo Corp.

and proprietary sodium alkyl sulfonates such as Alkanol®189-S available from E.I. du Pont de Nemours & Co.

Suitable polyhydric alcohols include aliphatic or arylalkyl polyhydric alco¬ hols containing two or more hydroxyl groups. Specific examples include glycer¬ ine, sorbitol, mannitol, xanthan gum, hexylene glycol, gluconic acid, gluconate salts, glucoheptonate salts, pentaerythritol and derivatives thereof, sugars, and alkylpolyglycosides such as APG®300 and APG®325, available from Henkel Corp. Especially preferred polyhydric alcohols include triglycerols, especially glycerine or fatty acid esters thereof such as castor oil triglycerides.

In accordance with the present invention, we have discovered that em¬ ploying alkoxylated, especially ethoxylated, castor oil triglycerides as lubricants and surface conditioners results in further improvements in can mobility espe¬ cially where operation of the can line is interrupted causing the cans to be ex¬ posed to elevated temperatures for extended periods. Accordingly, especially preferred materials include Trylox® 5900, Trylox® 5902, Trylox® 5904, Trylox® u 5906, Trylox® 5907, Trylox® 5909, Trylox® 5918, and hydrogenated castor oil derivatives such as Trylox® 5921 and Trylox® 5922, all available from Henkel Corp.

Preferred fatty acids include butyric, valeric, caproic, caprylic, capric, pel- argonie, lauric, myristic, palmitic, oleic, stearic, linoleic, and ricinoleic acids; ma- » Ionic, succinic, glutaric, adipic, maleic, tartaric, gluconic, and dimer acids; and salts of any of these; imiftodipropionate salts such as Amphoteric N and Am¬ photeric 400 mailable from Exxon Chemical Co.; sulfosuccinate derivatives such as Texapon®SH-135 Special and Texapon®SB-3, available from Henkel Corp.; citric nitrilotriacetic, and trimellitic acids; Cheelox® HEEDTA, N-(hydroxyethyl)- ethylenediaminetriacetate, available from GAF Chemicals Corp.

Preferred amides generally include amides or substituted amides of car* boxylte adds having from four to fwertfy carbons. Specific examples are Alkam- MjjMiiiMiiaBi—iMi—IIMfca —s WO 96/19553 PCT/US95/16014 ide® L203 lauric monoethanolamide, Alkamide® L7DE lauric/myristic aikanol- amide, Alkamide® DS 280/s stearic diethanolamide, Alkamide® CD coconut di- ethanolamide, Alkamide® DIN 100 lauric/linoleic diethanolamide, Alkamide® DIN 2951s linoleic diethanolamide, Alkamide® DL 203 lauric diethanolamide, all avail- able from Rhone-Pouienc; Monamid® 150-MW myristic ethanolamide,. Monam- id® 150-CW capric ethanolamide, Monamid® 150-IS isostearic ethanolamide, all available from Mona Industries Inc.; and Ethomid® HT/23 and Ethomid® HT60 polyoxyethylated hydrogenated tallow amines, available from Akzo Chemi¬ cals Inc.

,0 Preferred anionic organic derivatives generally include sulfate and sulfo¬ nate derivates of fatty acids including sulfate and/sulfonate derivatives of natural and synthetically derived alcohols, adds and natural products. Specific examp¬ les include: dodecyl benzene sulfonates such as Dowfax® 2Ai, Dowfax® 2AO, Dowfax® 3BO, and Dowfax® 3B2, all available from Dow Chemical Co.; Lomar® ,5 LS condensed naphthalene sulfonic acid, potassium salt available from Henkel Corp.; sulfosuccinate derivatives such as Monamate® CPA sodium sulfosuccin- ate of a modified alkanolamide, Monamate® LA-100 disodium lauryl sulfosuccin¬ ate, all available from Mona Industries; Triton® GR-5M sodium dioctylsulfosuc- cinate, available from Union Carbide Chemical and Plastics Co.; Varsulf® SBFA 2o 30, fatty alcohol ether sulfosuccinate, Varsull® SBL 203, fatty acid alkanolamide sulfosuccinite, Varsull® S1333, ricinoleic monoethanolamide sulfosuccinate, all available from Sherex Chemical Co., Inc.

Another preferred group of organic materials comprise water-soluble al- koxylated, preferably ethoxylated, propoxylated, or mixed ethoxylated and pro- zs poxylated materials, most preferably ethoxylated, and non-ethoxylated organic materials selected from amine salts of fatty acids including mono-, di-, tri-, and poly-acids, amino fatty acids, fatty amine N-oxides, and quaternary salts, and water soluble polymers.

Preferred amine salts of fatty acids include ammonium, quaternary am- monium, phosphonium, and alkali metal salts of fatty acids and derivatives there¬ of containing up to 50 moles of aikytene oxide in either or both the cationic or an¬ ionic species. Specific examples include Amphoteric N and Amphoteric 400 im- MfinMiiiriihriaiiMMIiiM PCT/US95/16014 WO 96/19553 hrimM* sodium sa,., avai.aWe ton Exxon Cmica, Co, Cfcnpha.® 154 LoL. N-taHo* W-P"**— and Deripha® 160, d,sod,um M-lau- beta iminodipropionate, available from Henkel Corp.

Preferred amino aoids indude alpha and beta amino aads and ftndt , and salts reof, induding alky, a alRoxyiminodropion. aoids and wr-* and sarcosine derivatives and their salts. Speoifio examples ,ndude Aeen® Z Nooo*e.ainob*ho add, available from AKzo Chemicals ha; Ampho- .erto M. Amphotehc 400, E»<on Che.ioa, Co, sarcosine (N-methyl glycne, hy- dnxyeyl glydne; Hamposy® TWO ttethanolamine laumyl sarcos,nate, Ham- ,0 pos 0 oley. s.rcosina.e, HaBposyl® AL-SO ammoniumlauroyl sarcos.nate ' Halposyl® L lauroy, sarcosinate, and Hamposy C cocoy, sarcos-nate, a„ available from W.R. Grace & Co.

Preferred amine N-oxides indude amine oxides where at least one alky.

substituen. contains at leas, .*ee carbons and up to 20 carbons. Specifc ex- . amples indude Aromox® C/12 bisK2.hydroxye.hyl).cocoalkylamine ox,de, Aro- moT/iabisKa+ydraxyethyDtallowalkylamine oxide, AromoDMC dmethyl- coooalkylamine oxide, Aromo OWT hydrogenated dimemyl.a.lowalkyiam.ne oxide AromoM.16 dimeftylheaxdecylalkylamine o»de, an available from Ak- zo Chemicals Inc.; andTomah® AO-14-2 and TomaMSAO.728 available from at Exxon Chemical Co. . .

Preferred quaternary salts include quaternary ammoraum denvahves of fatty amines cortanif* a. leas, oni substituen. containing from 12 to 20 ca*on atoms nd zero to 60 moles of ethylemoade and/or zero to ISmoles of propyl- ' eneoxidevemmecounterionconsistsof halide, sulfate, nittate, carboxylate, B aorarylsuHate.alkyloralsuecrdenva.iveslhereof. f- les indude Arqua.® 12-37W dodecyltrimethylammonium chloride, Arquad® 1B- octadecyMmmmonium chloride, Arquad® 210-50 didecyldimethylam- monium chlortde, ArquadS.218.100 diodadecyldimethylammonium chlonde, Ar- quad®316(W)Whexadecylmethylamr™)niumcNonde,A«,ua<»B.100d, . me«M(C,,iMa-*londe,E»»quad®C/12«XoylMl.

monium chlonde, fM* 025 cocomethyltPOEWmnu-r, d*.de, E.lxx.C/Wrsalt.EmoquaTmAcetatettse+vdroxyemylltallow- PCT/US95/16014 WO 96/19553 alkyl ammonium acetate, puoqaud®T-50 N,N,N',N-,N"-pentamethyl-N.tallow.1,3.

diammoniumdichloride,Propoquad®2HT/11di(hydrogenatedtallowalkyl)(2-hy- dfoxy.2-methylethyl)methylammonium chloride, Pr0poquad®T/12 tallowalkyL methyl-bis-(2-hydro)cy-2ethy!ethyl)ammonium methyl sulfate, all available from Akzo Chemicals Inc.; Monaquat® PTS stearamidopropyl PG-dimonium chlonde phosphate, available from Mona Industries Inc.; Chemquat® 12-33 lauryltrimeth- ylammonium chloride, Chemquat® 16-50 Cetyltrimethylammonium chloride ava.l- able from Chemax Inc.; and tetraethylammonium pelargonate, laurate, mynstate, ofiate, stearate or isostearate.

,0 Preferred water-soluble polymers include homopolymers and heteropoly- mers of ethylene oxide, propylene oxide, butylene oxide, acrylic acid and its de¬ rivatives maleic acid and its derivatives, vinyl phenol and its derivatives, and vin¬ yl alcohol. Specrfic examples include Carbowax® 200, Carbowax® 600, Carbo- wax® 900, Carbowax® 1450, Carbowax® 3350, Carbowax® 8000, and Com- pound 20M. all available from Union Carbide Corp.; Pluronic® L61, Plurohic® L81, Pluronic® 31R1, Pluronic® 25R2, Tetronic® 304, Tetronic® 701, Tetronic® 908, Tetronic® 90R4, and Tetronic© 15QR1, all available from BASF Wyandotte Corp.; Acusol® 410N sodium salt of polyacrylic acid, Acusol® 445 polyacrylic acidt Acusol® 460ND sodium salt of maleic acid/olefin copolymer, and Acusol® 2o 479N sodium salt of acrylic acid/maleic acid copolymer, all available from Rohm & Haas Company; and N-methylglucamine adducts of polyvinylphenol and N- methylethanolamine adducts of polyvinylphenol.

Additional improvements are achieved by combining with the organic material(s) noted above an inorganic material selected from metallic or ionic zir- conium, titanium, cerium, aluminum, iron, vanadium, tantalum, niobium, molyb¬ denum, tungsten, hafnium or tin to produce a film combining one or more of these metals with one or more of the above-described organic materials. A thir; film is produced having a coeffident of static friction that is not more than 1.5 and is less than the coefficient without such film, thereby improving can mobility in high speed conveying without interfering with subsequent lacquering, other pain¬ ting, printing, or ether similar decorating of the containers. This type of lubricant and suface conditioner is especially preferred when used in Stage 4 as defined ,l ....ajMai-mnmypJlip ,..,... *., ..v....-.>..A._>..-«'r f...- .jy-—»«».--*»~*v--'h'-mHW<lft >1,-r.f .f—.r tn» -~" —- -•'tmii'iVT iVirm-ttiThrlnWiw PCT/US95/16014 » 96/19553 above. .

The technique of incorporating such inorganic materials is descr.bed, in particular detail with reference to zirconium containing materials, in U.S. Patents 030 323 of July 9,1991 and 5,064,500 of November 12,1991, the entire d.s- ciosures of which, to the extent not inconsistent with any explicit statement herein are hereby incorporated herein by reference. The substitution of other metallic materials for those taught explicitly in one of these patents is within the scope of those skilled in the art.

In a further preferred embodiment of the process of the present invention, in order to provide improved water solubility, especially for the non-ethoxylated organic materials described herein, and to produce a suitable film on the can sur¬ face having a coefficient of static friction not more than 1.5 after drying, one em¬ ploys a lubricant and surface conditioner forming composition that includes one or more surfactants, preferably alkoxylated and most preferably ethoxylated, along with such non-ethoxylated organic material to contact the cleaned can sur¬ face prior to final drying and conveying. Preferred surfactants include ethoxylat¬ ed and non-ethoxylated sulfated or sulfonated fatty alcohols, such as lauryl and coco alcohols. Suitable are a wide class of anionic, non-ionic, cationic, or am¬ photeric surfactants. Alkyl polyglycosides such as C8 - C18 alkyl polyglycosides having average degrees of polymerization between 1.2 and2.0 are also suitable.

Other classes of surfactants suitable in combination are ethoxylated nonyl and 6uyl phenols containing from 1.5 to 100 moles of ethylene oxide, preferably a nonylphenol condensed with from 6 to 50 moles of ethylene oxide such as Ige- pal® 00-887 available from Rhone-Poulenc; alkyl/aryl polyethers, for example, Triton® DMe; and phosphate esters of which Triton® H-66 and Triton® QS-W are examples, all of the Trilon® products being available from Union Carbide Co., and Ethox® 2684 and Ethfac® 136, both available from Ethox Chemicals ln&, are representative examples; polyethoxylated and/or polypropoxylated de- rivatrves of linear and branched alcohols and derivatives thereof, as for example Trycol® 6720 (Henkel Corp.), Surfortic® LF47 (Huntsman Chemical Co.) and Antarox® LF430 (Rhohe-Poulenc); sulfonated derivatives of linear or branched aHprtatic alcohols, for example, Neodol® 2S4S (Shell Chemical Co.); sulfonated 1% umu T.TYTfl'i-TyH'- —--"-"S S||ii# WO 96/19553 PCT/US95/16014 aryl derivatives, for example, Dyasulf® 9268-A, Dyasulf® C-70, Lomar® D (Henkel Corp.) and Dowfax® 2A1 (Dow Chemical Co.); and ethylene oxide and propylene oxide copolymers, for example, Pluronic® L-61, Pluronic® 81, Pluronic® 31R1, Tetronic® 701, Tetronlc® 90R4 and Tetronic® 150R1, all s available from BASF Corp.

Surprisingly, it has been found that surfactants containing a phenanthrene ring structure, which is to be understood herein as contained not only in phenan¬ threne itself but in molecules made by hydrogenating phenanthrene to any de¬ gree not sufficient to break any of the three rings present in phenanthrene, are disadvantageous constituents of the lubricant and surface conditioner forming composition, at least if this composition also contains any inorganic material selected from metallic or ionic zirconium, titanium, cerium, aluminum, iron, va¬ nadium, tantalum, niobium, molybdenum, tungsten, hafnium or tin as described above. The formation of sludge is notably increased when such surfactants are present together with any of these inorganic materials. It has also been found that the tendency to sludge formation can usefullybe tested in a laboratory, without the need for actual can processing, by deliberately adding such soils as aluminum fines, soluble aluminum-containing species, drawing oils, and cleaner surfactants to the lubricant and surface conditioner forming composition to be zo tested for resistance to sludging, then passing the deliberately soiled composition through a spraying stage repeatedly and observing whether any dry floe is visible ©n the head of foam that forms in the container into which the spray drains. The presence or absence of dry floe in this test indicates, with at least rough quanti¬ tative correlation, whether or not sludge will likely become a problem in operating zs the lubricant and surface conditioner forming cemposition thus tested, and if so, the extent of the sludge formation likely to be observed in practical use.

Surfactants with a phenanthrene ring structure, especially abietate, hy- drogenated abietate, and alkoxylated abietate surfactants derived from natural rosin, am very commonly used new in the cleaning stage ©f container proeess- s* ing, before contact with any lubricant and surface conditioner forming composi- tion, for example m Stage 2 as shewn in Table A, Inasmuch as earry-over of some of the cleaner surfactants into the compositions used for later stages of -«*,. M -ms - ' ~* :-.,-U-- ;l- 'V if m-1! '' 'I- "iVffiiUfir i "l ' mil lUmfl i nimt .Til i WO 96/19553 PCTAJS95/16014 treatment can not be entirely avoided in practical high speed and high volume can processing, such cleaner surfactants should be used only with care and in limited amounts if at all in any processing stage prior to a lubricant and surface conditioner forming composition that includes inorganic material selected from metallic or ionic zirconium, titanium, cerium, aluminum, iron, vanadium, tantalum, niobium, molybdenum, tungsten, hafnium or tin as described above.

More specifically, it is preferred, with increasing preference in the order given and independently for each composition concerned, that (i) any lubricant and surface conditioner forming composition that contains inorganic material se- lected from metallic or ionic zirconium, titanium, cerium, aluminum, iron, vanadi¬ um, tantalum, niobium, molybdenum, tungsten, hafnium or tin as described above and (II) any cleaner or rinse composition that is contacted with the contain¬ ers to be provided with a lubricant and surface conditioner layer before the con¬ tainers are brought into contact with the lubricant and surface conditioner forming is composition, should contain not more than 5, 4, 3, 2,1, 0.5, 0.4,0.3, 0.2, 0.1, 0.05,0.04,0.03,0.02,0.01, 0.005, 0.004, 0.003, 0.002, 0.001, 0.0005, 0.0004, 0.0003,0.0002, 0.00Q1, 0.00005, 0.00004, 0.00003, 0.00002, or 0.00001 % in total of carbon atoms that are part of a phenanthrene ring structure as defined above. The minimization of concentration of phenanthrene ring containing com- zo pounds is particularly advantageous in connection with the use of lubricant and surface conditioner forming compositions as taught in U. S. Patents 5,030,323 and 5,064,500 Phenanthrene ring containing nonionic surfactants have bn extensively used for at least the last several years for cleaning aluminum containers, be- as cause they are highly effective in removing some of the kinds of organic soils of¬ ten found on such containers. However, it has now been ftnurid that alkyl phenol based nonionic surfactants can satisfactorily replace phenanthrene ring contain¬ ing surfactants for this purpose, and the alkyl phenol based surfactants do not promote sludge formation in metal containing lubricant and surface conditioner m forming compositions as do phenanthrene ring containing surfactants. Apartic- ulariy preferred combination of surfeetants for a cleaner stage preceding a metal containing lubficant and sutfaes eonditienef forming eompositiens comprises, .-,..- -—- -' fff»t\ .-. || .„.1-...1 f|.... - « t. t -r hit'n i iii ii tS*.

WO 96/19553 PCT/US95/16014 more preferably consists essentially of, or still more preferably consists of:

(A) a component of nonionic surfactants selected from the group consisting of surfactants corresponding to the chemical formula:

R|WHC,HjBP)bH where a is 0 or 1; R represents an alkyl moiety that may be branched or unbranched and saturated or unsaturated but does not include any aryl group and the sum of a plus the number of carbon atoms in R is from 10- 22, more preferably from 12-20, or still more preferably from 14 -18; n is an integer that is at least 2 and is not greater than 4, more preferably not greater than 3, most preferably 2 and may be different from one CnH2nO group to another in the same molecule; and b is an integer, the value or values of b being selected such that the hydrophile-lipophile bal¬ ls ance ("HLB") of the total component is, with increasing preference in the order given, not less than 8,10,10.5,11.0,11.3,11.5,11.7,11.8, 11.9, 12.0, or 12.1 and independently is, with increasing preference in the order given, not more than 20,18,16,15,14,13.7,13.5,13.3,13.1,12.9,12.8, 12.7, 12.6,12.5,12.4, or 12.3; and (B) a component of nonionic surfactants selected from the group consisting of surfactants corresponding to the chemical formula R'-CnHjnOH, where R' represents an alkyl moiety that may be branched or unbranched and saturated or unsaturated but does not include any aryl group and that has from 4 -16, more preferably from 6-14, still more preferably from 8 - zs 10, most preferably 9, carbon atoms; $ represents a phenyiene group; n is an integer that is at least 2 and is not greater than 4, more preferably not greater thsn 3, most preferably 2; and c is an integer, the value or val¬ ues of c being sisteeted such that the HLB of the total component is, with increasing presence in the order given, not less than 9,10.0,10.6 11.2, so 1t.7,12,2,12.5|t 12.7,119r 13.0,13.1,13.2, or 13.3 and independently is, with increasing preference in the order given, not more than 21,19,17, 16,15,14.7,14.Sr 14.3,14.1,13.9,13.8,13.7,13.6, or 13.5.

Independently, the ratio of component (A) to component (B) in the mixture preferably is, with increasing preference in the order given, not less than 0.1,0.2, iaMMMttHMM)gqtpMi|iMa*i WO 96/19553 PCT/US95/16014 0.3, 0.4, 0.5, 0.55, 0.59, 0.63, 0.60, 0.62, 0.64, 0.66, 0.67, 0.68, 0.69, 0.70, or 0.71 and independently preferably is, with increasing preference in the order given, not greater than 10,5,4, 3,2,1.5,1.2,1.1,1.0, 0.9,0.85,0.83, 0.81, 0.80, 0.79, 0.78, 0.77, 0.76, 0.75, 0.74, 0.73, or 0.72.

s The lubricant and surface conditioner for aluminum cans in accordance with this invention may comprise a phosphate acid ester or preferably an ethoxyl- ated alkyl alcohol phosphate ester. Such phosphate esters are commercially available as Gafao® PE 510 from GAF Corporation, Wayne, NJ, and as Ethfac® 136 and 161 and Ethox™ 2684 from Ethox Chemicals, Inc., Greeneville, SC. In io general, the organic phosphate esters may comprise alkyl and aryl phosphate esters with and without ethoxylation.

The lubricant and surface conditioner forming composition for aluminum cans may be applied to the cans during their wash cycle, during one of their treatment cycles such as cleaning or conversion coating, during one of their wat¬ ts er rinse cycles, or during their final water rinse cycle, in addition, the lubricant and surface conditioner may be applied to the cans after their final water rinse cycle, i.e., prior to oven drying, or after oven drying, by fine mist application from water or another volatile non-inflammable solvent solution. It has been found that the lubricant and surface conditioner is capable of depositing on the aiumin- urn surface of the cans to provide them with the desired characteristics. The lub¬ ricant and surface conditioner may be applied by spraying and reacts with the aluminum surface through chemisorption or physiosorption to provide it with the desired film.

Generally, in the cleaning process of the cans, after the cans have been zs washed, they are typically exposed to an acidic water rinse. In accordance with this invention, the cans may thereafter be treated with a lubricant and surface conditioner comprising an anionic surfactant such as a phosphate acid ester, in such case, the pH of the treatment system is important and generally should be acidic, that is between about 1 and about 6.5, preferably between about 2.5 and so about S. if the cans are not treated with the lubricant and surface conditioner of this invention next after the acidic water rinse, the cans are often exposed to a tap water rinse and then to a deionized water rinse. In such event, the deionized k-to***- - ...-ij-r-ftf-'.tftww ffi1T[,'J,-'AjKr''JililTfif'rt-rttt-l'-,*J*-t",,'-',-',,vl-'''''|,f1'f ''"-"'"''" r-|i»l'""" PCT/US95/I6014 WO 96/19553 r rinse sdutton iS prep, to contain the .ubncant and surface —- compost or mis Mftn «** «-» «-«*• a S~ IZd J I. intoned poiyoyiated aicohols or poiyohyiated rTor any d me otr su«e matena,, as described above. After such , rSCnlr.ybepassedtoano.en.ordpdorto.urmerprocess.

Theanntofiubncandsurfacecoitionertobeappliedtomecans ,«. ted.nology described herein to providing tubrican* and surface cor*»- B ortincansespeciaiiy.oaidindeweteringanddry.ngo.suchcan. The For a (u»er appreciation of me invention, reference may be made to the WkMingexamp1es,v«1are.nedK,bemere,ydescrip.ive. iiiustrat.ve. and not limiting as to the scope of the invention.

gimpte i This exampte Mates the amoum of aiumi can iubrican. and surface nrnecessaimprovemeofcansthroughthe tracks and ssofaninduscanmanufagfaandsma ' me iubric** ** surface condor does no, have an adverse effect on the ad „ iondiabentedmeoudesurfaceasweiiasofiacuerssprayedon the inside surface of the cans.

Ti*— *« cans obtned from an industria, can manuact-r washed dean «im an alkaiine Cear avaiiabie from me ParRer Amchem Z Hee, Coo.oraBon, Madison Heights, Ml. empioying •--W.

passinglAeamat.Um.. n»cansWerewa.edWmd1fferertan»un«rt LsurfccndiUonerinm.Mrinsesofme washer andmen - ..y.... > ...,,. .f.a PCT/US95/16014 WO 96/19553 dned in an oven. The .ubricart »l «*fa=e conditioner comprised abou. a 10% Lveconofpolyoatedisostearate, an MM non,on,csu - S« available under .he tradename BW" MM4 from Bhox Chem,ca s, rLrwiM.SC. Theueated-eedtomecanmanuacturer , .inespeedandprwngcuamyevaon. The printed cans were d,v,ded .no ".eachconsistingtoecan,. A.weresubiectedr20m,nu.esto one of the following adhesion test solutions:

Test Solution A: 1% Joy® (a commercial liquid dishwash,ng detergent, Procter and Gamble Co.) «*** in 3:1 deionized wa.er.ap water a. a tempera- " '""'TSoiaionB: 1% Joy® detergent solution in deionized water at a tern- WWr removing tl* girted car««om M adhesion test soluton. each can oossatted using a sharp n»mloyec..o expose lines of aluminum wh,ch . shcMedWughmepain.orlaer.d.estedforpaintadhasion. Th.stesur.

dudedapplyingBcoUansparen.mpe No. BlOtoly over me crossmatched area and men drawing ft. Bpe ba* agains. i.sel. with a rapid pulling mouon suthatttetape was puiled away frcxnme cross-hatched area. The results rf ftetestwere rated asfollows: 10, perfect, when the tape did not peel any pa.nt . *ommesuface;8,acoepteble:andO,U>.alfailure. The cans were visually ex- amined for any print or lacquer pick-off signs.

.n addiUon, me cans were evaluated for their coefficient of stafcfncfon usinga labora.«y s.a«c«c.ion Mr. This device measures me staticfriCion associated with the sace araderistics of aluminum cans. This is done by » using a ramp which is raised thngh an arc of 90- by using a constant speed motor a spool and a cable attached to me free swinging end of me ramp. A cradleanachedtothebottomofmerampisusedtoholdacansinhorizonuipo- •sHion approximately 0.5 inches apart with me domes facing me fixed end of the ramp A third can is laid upon me 2 cans with the dome facing the free sw.ng.ng . endofmeramp.andmeedgesofaiucansarealignedsomatmeyareeven with each other.

AS the ramp begins to move through its arc a timer is automafcally actu- n mmtmi a. . ,.u..w.,w.,.

"f 11 "rir,~~t"*"*-*";;***'aa'i WO 96/19553 PCT/US95/16014 ated. When the ramp reaches the angle at which the third can slides freely from the 2 lower cans, a photoelectric switch shuts off the timer. It is this time, record¬ ed in seconds, which is commonly referred to as "slip time". The coefficient of static friction is equal to the tangent of the angle swept by the ramp at the time the can begins to move.

The average values for the adhesion test and coefficient of static friction evaluation results are summarized in Table 1 which follows:

Table 1 TestNo. Lubricant andSurfaceConditionerConcentrate(%/vol.) Arihpsinn EvaluationTestSolu¬tion OSW ISW ID 1 Coeflicient ofStaticFriction 1 Control (notreatment) m~m 1.42 2 0.1 8 10 10 10 0.94 3 0.25 A 10 10 10 _ 4 0.5 B 9.5* 10 10 0.80 0.75 A 10 10 10 0.63 6 1.0 B 10 10 10 0.64 7 2.0 A 10 10 10 0.56 8 5.0 B 10 10 10 0.55 9 10.0 A 9.8* 10 10 0.56 *Little pick-off was visually noticed on the outside walls, mainly at the contact marks.

In Table 1, "OSW" stands for outside sidewall, "ISW stands for inside sidewall, and "ID" stands for inside dome.

In brief, it was found that the lubricant and surface conditioner forming eemposftion as applied to foe deaned aluminum cans provided improved mobility to the cans even at very low active ingredient concentrations, and it had no ad- versa effect en either adhesion eftabeT print of internal lacquer tested even at MHaapaMllMpiiqMgpiMjWi MMUMMMMMtiiia" WO 96/19553 PCT/US95/16014 to 1CX) times the required use concentration to reduce the coefficient of static fric¬ tion of the cans.

Example II This example illustrates the use of the aluminum can lubricant and surface s conditioner of Example I in an industrial can manufacturing facility when passing cans through a printing station at the rate of 1260 cans per minute.

Aluminum can production was washed with an acidic cleaner (Ridoline ® 125 CO, available from the Parker Amchem Division, Henkel Corporation, Madi¬ son Heights, Ml), and then treated with a non-chromate conversion coating (Alo- io dine® 404, also available from the Parker Amchem Division, Henkel Corporation, Madison Heights, Ml). The aluminum can production was then tested for "slip" and the exterior of the cans were found to have a static coefficient of friction of about 1.63. During processing of these cans through a printer station, the cans could be run through the printer station at the rate of 1150 to 1200 cans per min¬ is ute without excessive "trips", i.e., improperly loaded can events. In such case, the cans are not properly loaded on the mandrel where they are printed. Each "trip" causes a loss of cans which have to be discarded because they are not ac¬ ceptable for final stage processing.

About 1 ml/liter of aluminum can lubricant and surface conditioner was added to thfc deionized rinse water system of the can washer, which provided a reduction of tie static coefficient of friction on the exterior of the cans to a value of 1.46 or a reduction of about 11 percent from their original value. After passing the cans through the printer, it was found that the adhesion of both the interior and exterior coatings were unaffected by the lubricant and surface ctnditioner.

zs In addition, the printer speed could be increased to its mechanical limit of 1250 to 1260 cans per minute without new problems.

In similar fashion, by increasing the concentration of the aluminum can lubricant and surface conditioner forming composition in the deionized rinse wa¬ ter system, it was possible to reduce the coefficient of static friction of the cans so by 20 percent without adversely affecting the adhesion of the interior and exterior coatings of tfie cans. Further, Hwas possible to maintain the printer speed con¬ tinuously at 1250 cans per minute fof a 24-hour test period.

rtiaattiiaMttaiiift MWtfMHilHHMM WO 96/19553 PCT/US95/16014 Example HI This example illustrates the use of other materials as the basic component for the aluminum can lubricant and surface conditioner.

Aluminum cans were cleaned with an alkaline cleaner solution having a pH of about 12 at about lOS'F for about 35 seconds. The cans were rinsed, and then treated with three different lubricant and surface conditioners comprising various phosphate ester solutions. Phosphate ester solution 1 comprised a phosphate acid ester (available under the tradename Gafac® PE 510 from GAP Corporation, Wayne, NJ) at a concentration of 0.5 g/l. Phosphate ester solution 2 comprised an ethoxylated alkyl alcohol phosphate ester (available under the tradehpme Ethfad© 161 from Ethox Chemicals, Inc., Greenville, SC) at a concen¬ tration of 0.5 g/l. Phosphate ester solution 3 comprised an ethoxylated alkyl alco¬ hol phosphate ester (available under the tradename Ethfac® 136 from Ethox Chemical!? c., Greenville, SC) at a concentration of 1.5 g/l.

The iiobility of the cans in terms of coefficient of static friction was evaluated and found to be as follows:

Phosphate Ester Solution pH None 3.6 Coeflkient of Static Friction 0,47 3.3 2.6 0.63 0.77 1.63 The aforementioned phosphate ester solutions all provided an acceptable mobility to aluminum cans, but the cans were completely covered with "water- break". It is desired that the cans be free of water-breaks, i.e., have a thin, continuous film of water thereon, because otherwise they contain large water droplets, and the water film is non-uniform and discontinuous. To determine whether such is detrimental to printing of the cans, they were evaluated for adhe- sioa That is, the decorated cans were cut open and boiled in a 1 % liquid dish¬ washing detergent solutipn (Joy®) comprising 3:1 deionized water.tap water for ten minutes. The tans were then rinsed in deionized water and dried. As in Ex- - — - - --~—---—"~-"-«t' WO 96/19553 PCT/US95/16014 ample I, eight cross-hhed scribe lines were cut into the coating of the cans on the inside and outside sidewalls and the inside dome. The scribe lines were taped over, and then the tape was snapped off. The cans were rated for ad¬ hesion values. The average value results are summarized in Table 2.

Table 2 Phosphate ester Solution Control osw 9.8 Adhesion Rating ISW ID 9.8 L 6.8 1.0 In Table 2, "OSW stands for "outside sidewall", "ISW" stands for "inside sidewall", and "ID" stands for "inside dome".

For the control, it was observed that there was no pick-off (loss of coating adhesion) on either the outside sidewall, the inside sidewall or the inside dome of the cans.

For phosphate ester solution 1, it was observed that there was almost no pick-off on the outside sidewall, substantial pick-off on the inside sidewall, and complete failure on the inside dome of the cans.

For phosphate ester solution 2, it was observed that there was almost no pick-off on the outside sidewall, and no pick-off on the inside sidewall and no pick-off on the inside dome of the cans.

For phosphate ester solution 3, it was observed that there was no pick-off on the outside sidewall, the inside sidewall, and the inside dome of the cans.

Example IV This example illustrates the effect of the lubricant and surface conditioner of mis invention on the water draining characteristics of aluminum cans treated therewith.

Aluminum cans were cleaned with addie cleaner (Ridoline® 125 CO fol- WO 96/19553 PCT/US95/16014 lowed by Alodine ® 404 treatment or Ridoline® 125 CO only) or with an alkaline cleaner solution (Ridoline® 3060/306 process), all the products being available from the Parker Amchem Division, Henkel Corporation, Madison Heights, Ml, and then rinsed with deionized water containing about 0.3% by weight of a lubricant and surface conditioner of this invention. After allowing the thus-rinsed cans to drain for up to 30 seconds, the amount of water remaining on each can was de¬ termined. The same test was conducted without the use of the lubricant and sur¬ face conditioner. The results are summarized in Table 3.

Table 3 Drain Time,Seconds Water Remaining. Grams per Can With DI Water With 0.3 % Conditioner 6 2.4 , 3.0 not determined 12 2.1-3.5 2.8 18 2.2-3.5 2.3 1.8-3.4 2.3 It was found that the presence of the lubricant and surface conditioner caused the water to drain more uniformly from the cans, and that the cans re¬ mained "water-break" free for a longer time.

Example V This example illustrates the effect of the oven dryoff temperature on the srdewall strength of aluminum cans. This test is a quality control compression test which determines the column strength of the cans by measuring the pres¬ sure at which they buckle. The results are summarized in TaM 4.

itmnmnatiiaUmmi.

i v,mr WO 96/19553 PCT/US95/16014 Table 4 Oven Temperature (" F) Column Strength (PSD 86.25 87.75 88.25 89.25 It can be seen from Table 4 that at an oven drying temperature of 380° F, a 2 psi increase was obtained in the column strength test compared to the value obtained at 440° F oven temperature.

The higher column strength test results are preferred and often required because the thin walls of the finished cans must withstand the pressure exerted from within after they are filled with a carbonated solution. Otherwise, cans hav¬ ing weak sidewalls will swell and deform or may easily rupture or even explode.

It was found that the faster water film drainage resulting from the presence there¬ in of the lubricant and surface conditioner composition of this invention makes it possible to lower the temperature of the drying ovens and in turn obtain higher column strength results. More specifically, in order to obtain adequate drying of the rinsed cans, the cans are allowed to drain briefly before entry into the drying ovens. The time that the cans reside in the drying ovens is typically between 2 and 3 minutes, dependent to some extent on the line speed, oven length, and oven temperature. In order to obtain adequate drying of the cans irHhi! time¬ frame, the oven temperature is typically about MO" F. However, in a series of tests wherein the rinse water contained about 0.3 % by weight of a lubricant and surface conditioner of this invention, it was found that satisfactory drying of the cans could be obtained wherein the oven temperature was lowered to 400° F, and then to 370' F, and dry cans were still obtained.

Examples Groub VI Uncleaned aluminum cans from an industrial can manufacturer are washed clean In examples Type A with alkaline cleaner available from Pafker Amchem Division, Henkel Corporation, Madiseffi Heights, Michigan, employing <mi 'i'" W096/19553 TCVUBHimU the Ridoline® 3060/306 process and in Examples Type B with an acidic cleaner, Ridoline® 125 CO from the same company. Following initial rinsing and before final drying, the cleaned cans ere treated with a lubricant and surface conditioner comprised of about a 1% by weight active organic (I) in deionized water as speci- s fied in Table 5 below. In a separate set of examples, following initial rinsing and before final drying, the cleaned cans are treated with a reactive lubricant and sur¬ face conditioner comprised of about a 1% active organic (I) in deionized water plus about 2 gm/l (0.2wt%) of the inorganic (II) as specified in Table 5, below.

In yet another set of examples, following initial rinsing and before final drying, the io cleaned cans are treated with a lubricant and surface conditioner comprised of about i% active organic (I) in deionized water plus about 0.5% by weight of sur¬ factant (III) specified in Table 5, below. In a further set of examples, following ini¬ tial rinsing and before final drying, the cleaned cans are treated with a reactive lubricant and surface conditioner in deionized water comprised of about 1 % ac- is five organic (I), about 0.2% inorganic (II), about 0.5% surfactant (III) as specified in Table 5, below.

.S n WO 96/19553 ... J.- .... .V»'r.i>1.Ui-.;>li''T-ffri»»* PCT/US95/16014 WO 96/19553 PCT/US95/16014 PCTAJS95/16014 ft WO 96/19553 PCT/US95/16014 WO 96/19553 PCT7US95/16014 ---"- "- ' — -. ' r <• ii n1 i i ' i ii PCTAJS95/16014 W096/195S3 Fvampla and nomparisop Pyampla Group VII Two different surfactant combinations were prepared. The first consisted of sURFONICLF-ITandTRITONN-IOIinaratioofHlilSS. Thesecond consisted of EMULSOGEN™ TP-2144, TRYCOL™ LF-1, and ANTAROX LF-330 in a ratio of 201:64.5:64.5. All of these tradenamed surfactants are alkyl polyeth- ers, except for TRITON™, which is a nonyl phenol ethoxylate, and EMULSO- GEN™ TP-2144, which is ethoxylated rosin and therefore contains a phenan- threne ring structure.

About 0.2 % of each surfactant combination was added to separate batch- ro es of aqueous sulfuric and hydrofluoric acids in the amounts usied in conventional acid cleaner for aluminum cans, and these acid-surfactant combinations were used as the base treatment liquid for Stage 2 as defined in Table A above. In order to simulate the build-up of lubricant and aluminum containing species that would occur in normal extended use of such a cleaner for processing large vol- umes of aluminum cans, there were also added to these cleaning compositions (i) 2 g/L of a lubricant mixture consisting of 30 parts of DTI™ 5600 M3 cupper lubricant, 37 parts of DTI™ 5600 WB coolant, and 33 parts of Mobil™ 629 hy¬ draulic lubricant (the products including the letters "DT!" in their designations above are commercially available from Diversified Technology Inc., San Antonio, zo Texas, USA) and (ii) sufficient sodium aluminate to correspond to 1980 parts per million stoichiometric equivalent of aluminum. For further simulation of extended operations, Stage 3 as defined in Table A contained 5 % by volume of the clean¬ er solution in tap water as its treatment liquid, and, in some of the experiments, Stage 4 as defined in Table A in which the treatment liquid was primarily FIXO- DINE® 500, was "contaminated" with 0.25 or 1.0 % of the cleaner bath, while in other experiments, the Stage 4 treatment liquid was left free from any cleaner bath. (It has been determined by extensive experience that at equilibrium a treat¬ ment liquid which is routinely overflowed by addition of less contaminated solu¬ tion will contain about 5 % by volume of the treatment liquid from the previous ss process stage in addition to its nominal, deliberately added constituents. Stages 2 and S treatment liquids art normally routinely overflowed, while Stage 4 treat¬ ment liquid normally is not thersfom, Stage 4 treatment liquid can become y m mors centaminated than would be axpeetad from carry-over of 5 % of the PCT/US95/16014 WO 96/19553 Stage 3 treatment liquid, xvhich would correspond to a content of 0.25 % of the Stage 2 treatment liquid.) In all these experiments, it was observed that the Stage 4 bath developed sludge when the acid cleaning solution containing the second surfactant combi- nation were used, but remained free from sludge when the acid cleaning solution containing the first surfactant combination was used.

Pvamplfl and Compflrisnn Example Group VUI These examples and comparison examples were performed on an actual commercial cleaning line, in a plant where the primary materials to be cleaned ,0 were DTI™ 5600 M3 cupper lubricant, DTI™ 5600 WB coolant, and Mobil™ 629 hydraulic lubricant. The cleaner used as Stage 2 in the preferred example ac¬ cording to the invention for this group consisted when fresh of 450 parts of aque¬ ous sulfuric acid with a density of 66- BaumS, 93 parts of TRITON™ DF-16 (commercially available from Union Carbide Corp., reported to have an HLB val- « ue of 11 .€ and to consist of ethoxylated and then terminally propoxylated linear alcohol molecules with from 8 to 10 carbon atoms in the alcohol residue), 7 parts of PLURAFAC™ D-25 (commercially available from BASF Corp., reported to have an HLB value of 10.0 and to consist of molecules of the same type as de¬ scribed above for TRITON™ DF-16, except that there are from 10to 16 carbon atoms in the alcohol residue), and 450 parts of water. The Stage 4 treatment li¬ quid when fresh was FIXODINE® 500.

These treatment liquids were operated in actual cleaning, with convention¬ al overflowing and replenishment of the various treatment liquids, of more than 1400 aluminum beverage cans per hour for about seven months of continuous » operation (except for possible occasional brief line stoppages necessitated by equipment malfunctions or routine maintenance; these are believed not to total more than an average of three days per month). The Stage 2 treatment liquid was maintained at 140 ± 2 * F and the Stage 4 treatment liquid was maintained atHOit'F.

During this operation, at intervals the concentrations of free acid and "Re¬ action Pf ©duct" in the Stage 2 treatmertt liquid were measured as described in Parker AmftTachnfeai Preesss Sultetin N& ©71, Revision of April 19,1989, WO 96/19553 PCr/US95/16014 ment liquid were measured as described in Parker Amchem Technical Process Bulletin No. 1373, Revision of September 22,1994. The concentrations of dis¬ solved aluminum in parts per million in the Stage 2 and Stage 4 treatment liquids are known to be within ± 10 % of the value obtained by multiplying the Reaction Product value by 90 for Stage 2 and by 18 for Stage 4. The concentrations of the TRITON™ DF-16 (abbreviated below as "DF-IB") and PLURAFAC™ D-25 (abbreviated as "0-25" below) surfactants were calculated from the free acid val¬ ues by assuming that all the free acidity came from complete ionization of the sulfuric acid in the fresh Stage 2 treatment liquid and that the surfactants were present in the same ratios to the sulfuric acid as in the fresh Stage 2 treatment liquid. Some of the more pertinent values are shown in Table 6 below. In all these instances, the Stage 4 treatment liquid remained free from any discernible sludge, either in suspension in the liquid or atop the foam layer that normally is present dyrtng steady state operations in the Stage 4 treatment liquid tank.

TableG Characteristic Value for Characteristic after the FollowingNumber of Days of Operation:

For Stage 2:

Points of Free Acid 16 14 14 14 14 14 ppm of Dissolved AT1 1080 990 900 1260 990 9901.52 g/L of DF-16 1.74 1.52 1.52 1.52 1.52 g/LofD-25 0.13 0.11 0.11 0.11 0.11 0.11 For Stage 4:

pH 2.6 2.7 2.7 2.6 2.6 2.6 Points of Free Acid nm. 1.0 1.0 1.2 1.5 1.5306 ppm of Dissolved At*9 nm. 252 72 284 306 % of Cani that Were Water-Br eak-Free after Stage 6:

OnEiterior too 100 too too too 100 I On Interior 90 too too too 100 too h, .... ... . y.L(—---J iL- .- ; ' '-iiii llnlr*1~m' 5? WO 96/19553 PCT/US95/16014 In contrast to this, in an otherwise similar production operation in which the Stage 2 treatment liquid contained a surfactant based on ethoxylated rosin acids including a phenanthrene ring structure, solid sludge was observed to ac¬ cumulate atop the foam layer in the Stage 4 treatment liquid tank. From there, the sludge was occasionally dispersed into various other treatment solutions in the process line and when so dispersed often transferred to the surfaces of the treated cans, causing failures of complete coverage of the can surface by later applied lacquer. Such failures of complete coverage require rejection of the cans in question, and they occurred frequently enough that corrective measures were required to maintain the commercial economic viability of the processing oper¬ ation.

_____ ,,. .. . , , . .[n-TI — :.Tr '' n .aataaiM——w WO 96/19553 PCT/US95/16014 (0 The invention claimed is:

A process comprising steps of:

cleaning an aluminum can with an aqueous acidic cleaning solution com¬ prising a surfactant component and ' («) contacting the aluminum can after step (I) with an aqueous lubricant and surface conditioner faming composition, distinctfrom said aqueous acidic eteanmg solution, said aqueous lubricant and surface condffioner compris¬ ing as dissolved, dispersed, or both dissolved and dispersed components therein (i) water-soluble organic material selected from phosphate esters alcohols, fatty acids including nw, di, tri-, and poly-adds; fatty acid d* nvatives Muding salts, hydraxyadds, amides, esters, effie*, and deriva¬ tives thereof, and mixtures thereof, and (ii) a. leas, one of the elements selected fam ionium, fitanium, cerium, aluminm, iron, tin. vanadium tamalum, niobto, mdybden. tgaen, and h c form, -»* I. inpovement copses utilizing an aqueous add deaning solutton •- cons no, more man about 0.1 % of carion atoms that are pari of phenan- ftrene nngs and an aqueous ..iprican, and surface condiUoner forming composi- Hon that conte,ns not more than about 0.01 « of carton atoms that are part of phenanthrene rings. H