CA2225757A1 - Composition and process for treating the surface of aluminiferous metals - Google Patents
Composition and process for treating the surface of aluminiferous metals Download PDFInfo
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- CA2225757A1 CA2225757A1 CA 2225757 CA2225757A CA2225757A1 CA 2225757 A1 CA2225757 A1 CA 2225757A1 CA 2225757 CA2225757 CA 2225757 CA 2225757 A CA2225757 A CA 2225757A CA 2225757 A1 CA2225757 A1 CA 2225757A1
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C22/05—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
- C23C22/06—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6
- C23C22/40—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing molybdates, tungstates or vanadates
- C23C22/44—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing molybdates, tungstates or vanadates containing also fluorides or complex fluorides
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C22/05—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
- C23C22/06—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6
- C23C22/34—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing fluorides or complex fluorides
- C23C22/36—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing fluorides or complex fluorides containing also phosphates
- C23C22/361—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing fluorides or complex fluorides containing also phosphates containing titanium, zirconium or hafnium compounds
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- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemical Treatment Of Metals (AREA)
Abstract
A highly corrosion resistant and paint adherent surface coating on aluminiferous metals can be provided very rapidly, if desired in less than one second, by contacting the surface with an aqueous acid liquid treating composition containing as solutes specified proportions of phosphate ions, titanium containing materials, fluoride, and an accelerator; the accelerator is preferably at least one of nitrous acid, nitric acid, tungstic acid, molybdic acid, permanganic acid, water soluble salts of all of these acids, and water-soluble organoperoxides.
Description
-CA 0222~7~7 1997-12-24 W~ 9'T~V2369 PCTIUS96/10683 Deso, i,t,lion COMPOSITION AND PROCESS FOR TREATING THE SURFACE OF
ALUMINIFEROUS METALS
Technical Field This invention relates to a novel liquid surface l,t:dl",ent composition and process for application to aluminiferous metals, which provide the surface of aluminiferous metals, i.e., aluminum and aluminum alloys containing at least 65 % by weight of aluminum, with an exce"enl corrosion r~sisldnce and paint adher-ence. The pr~senl invention is applied with particularly good effect in the surface treatment of aluminum alloys in coil and sheet form.
Background Art Liquid cornposiliG"s, which hereinafter are often called "baths" for brevity, 0 even if used by some other method than immersionl that are in general use for treating the surface of alu,.,:. ,ir~r~ us metals can be broadly classiried into chrom-ate types and "o, Ic hrun Idte types. Chromic acid chromate conversion baths andphosphoric acid cl~,or"ale conversion baths are typical embodi",enL:, of chrom-ate type l,eal"~ent baths.
Chromic acid chrol "ate conversion baths came into prd~lical use in about 19~0 and are still widely used even at present for heat e,~cl ,a, .ger fln stock and aviation vehicle CGI I IpGi ~enl:j. The chr~, .,ic acid chromate conversion baths con-tain cl.r~,mic acid and fluoride as their main co,..ponents, with the fluoride func-tioning as a rtd-;tiOn ~cc~lerak~r. These baths coat metal surfaces with conver-20 sion codlillgs containing some quantity of hexavalent chromium.
Phosphoric acid cl.r~,-.ate conversion baths oliyindttd with the invention rljsr,loserl in United States Patent Number 2,438,877. These conversion baths, which couldi" ch"or.,ic acid, phospl)oric acid, and hydrofluoric acid as their main components, coat metal surfaces with conversion coatings whose main compon-25 ent is hydrated chromium pllosphale. Recallse these conversion codlil ,gs do notcol)l~in hexavalent chromium, they also are in wide use at present, for such ap-tions as underpaint coatings for beverage can body and lid stock. Neverth~less, since these chrur"dle type surface l,t:dl",ent baths do themselves contain toxic hexavalent cl,rol"ium even though the codli,)gs produced by them do not, CA 0222~7~7 1997-12-24 hexavalent chromium-free treatment baths are desired in view of the environ-mental problems from disposal of the baths, rinse waters, and the like.
Typical of the inventions in the field of the chromium-free nonchromate type surface treatment baths is the process disclosed in ~apanese Patent Appli-cation Laid Open EKokai or Unexamined} Number~;ho 52-~31937 [131,937/
1977]. The treatment bath in that reference consists of an acidic (pH approxi-mately 1.5 to 4.0) aqueous coating solution containing phosphate, fluoride, and zirconium or titanium or both. Treatment of the metal surface with this surface treatment bath forms thereon a protective coating whose main component is zir-~0 conium or titanium oxide. (This type of coating is often called a "conversion"
coating, bec~ e it is believed that it also con Ldil IS cations from the substrate in the form of oxides and/or phosphates.) An advantage of nonchromate surface treatment baths is that they are free of hexavalent cl ,romium, and this advantage has resulted in their wide use at the present time for treating the surface of drawn-and-ironed ("Dl") aluminum cans and the like. However, the nol ,cl ,ro" ,dle baths require longer lledll nel ll times for codli"y fc.l " ,dlion than cl ,ru, nale surface l",enl baths. Shortening surface treatment times has become an important issue in the last few years, because of the increasingly high line speeds being used to boost productivity. Moreover, nonchromate baths yield cGdlil,gs with a CGI l OSio" r~sislance and paint adherence inferior to those of c:hro" ,ate codlil lys.
The treatment process liiscloserl in Japanese Patent Application Laid Open [Kokai or Unexamined] Number Hei 1-246370 [246,370/1989l is an inven-tion whose object is to shorten the aforementioned surface treatment tirnes. In this process, the aluminiferous metal surface is first cleaned with an alkaline de-greaser and the cleaned surface is then treated with an acidic (pH 1.5 to 4.0) aqueous solution co,-l~i"ing 0.01 to 0.5 g/L of zirconium ions, 0.01 to 0.5 g/L of phosphate ions, 0.001 to 0.05 g/L, measured as its stoichiometric equivalent as fluorine atoms, of "free" fluoride ions, and optionally 0.01 to 1 g/L of vanadium ions. However, when this process is applied to Dl aluminum cans, the resulting film does not always have a satisfactory resistance to blackening.
Another nonchrur"ale l,edl"~ent process is rl j~clo5ed in Japanese Patent Publication Number Sho 57-39314 [39,314/1982]. Disclosecl therein is a treat-CA 0222~7~7 1997-12-24 wa~ 97102369 PCT/US96/10683 ment process in which the aluminiferous metal surface is treated with an acidic solution containing hydrogen peroxide, one or more selections from zirconium and titanium salts, and one or more selections from phosphoric acid and con-densed ,~ hosphoric acids. However, this treatment bath is ~-llsl b'~, and, in addi-tion, is also ir.~e~u~y rapid in terms of surface codli"g formation. Moreover, this document does not provide a specific descri~,Lion or disclosure of the treat-ment time, treatment temperature, or treatment process.
It is for these reasons that nonchromate tvpe surface treatment baths are at present almost never ùsed on surface treatment lines for aluminiferous metal ~o coil or sheet where short treatment times are critical.
In summary, then, there has yet to become established in the art a com-position or process for treating the surface of aluminiferous metals that can pro-vide short Ll't:dllllen~ times and is capable of for"~i"g a highly corrosion-resistant and strongly paint-adherent coaling, but is free of hexavalent cl ,run~ium.
Disclosure of the Invention Problemfs) to Be Solved by the Invention The pr~senL invention is dir~ ed to solving the problems .lescribed above for the prior art. In specific terms, the pr~:senl invention provides a composition and pr~cess for ll~dli.l~ the surface of aluminiferous metals that are able to form rapidly a very corrosion-resistant and highly paint-adherent coali"g on the sur-face of aluminiferous metals.
Summar,v of the Invention It has been discovered that a surface treatment composition containing dissolved phosphate ions, dissolved titanium containing substance(s), and dis-solved fluoride in particular relative quantities and a particular relative quantity of accelerator selechd from a specific group of chemical sub~ldnces can rapidly form a very cor,usion-resistant and highly paint-adherent coating on the surfaceof alun,i,,irt:,uus metals. The present invention was achieved based on this dis-covery.
A concenl,dle or working composition according to the present invention for treating the surface of aluminiferous metals characteristically comprises, preferably consists essentially of, or more preferably consists of, water and the CA 0222~7~7 1997-12-24 following materials in the relative proportions stated as follows: from 0.010 to 5 parts by weight of phosphate ions; from 0.010 to 2.0 parts by weight, C~ Gl ~lAted as its sloichiometric equivalent as titanium atoms, of dissolved titanium contain-ing substance(s); from 0.010 to 12 parts byweight, CAIClll~t~d as its stoichiomet-ric equivalent as fluorine atoms, of dissolved molecules and/or anions containing fluorine; and from 0.010 to 2.0 parts by weight of dissolved AGcelerator. The bases for the specification of these particular weight proportions for each com-ponent will be explained in sequence in the disc~ ~ssion of the composition of pre-ferred surface treatment baths, vide infr~. Cou"l~rio"s for the necess~y constit-~o uents e~pli -itly recited above are also necessAry if needed for ele.;l, ical neutral-ity.
The Accelerator incr~ases the speed of COdlil l9 rO~,,IdliOI I and is selected from the group consisling of oxyacids, such as tungstic acid (i.e., H2WO4), molyb-dic acid (i.e., HMoO3), permanganic acid (i.e., HMnO4), nitric acid (i.e., HNO3), nitrous acid (i.e., HNO2), hypochlorous acid (i.e., HCIO), chlorous acid (i.e., HCIO2), chloric acid (i.e., HC103), bromic acid (i.e., HBrO3), iodic acid (i.e., Hl03), perchloric acid (i.e., HC104), perbromic acid (i.e., HBrO4), periGclic acid (i.e, Hl04), orthopel iodic acid (i.e., H51O6), and salts of oxyacids; peroxoAcids, such aspe,~xo",oi,osulfuricacid (i.e., H2SO5), peruYodis~lfuricacid (i.e., H2S2O8), per-oxoll,o,lophosphoric acid (H3PO5), peroxodiphosphoric acid (i.e., H4P2O8), per-oxomonocarbonic acid (i.e., H2CO4), peroxodicarbonic acid (i.e., H2C2O6), and any of the per~xobGric acids (i.e., HBO3-1/2H20, HBO4-H20, or HBO5-H20), and salts of peroxoArids; higher valent metal cations of metals with at least two stable cationic valence states, in caliol-s that do not include oxygen, in aqueous so-lution, such as tetravalent cerium (i.e., Ce+4), trivalent iron (i.e., Fe+3), and tetra-valent tin (Sn4+); hydll,geo peroxide (H2O2); and water-soluble organoperoxides.The use of an accelerator selected from this group in a treatment composition according to the p resel-L invention yields a s~ ~hst~ntial improvement in the speed of fo" ~ IdLiOn of a sufficiently thick coating to have protective qualities and in the corrosion resistance and paint adherence of the coating thereby formed.
The four necessary active ingredients in a composition according to the invention as desc,iL,ed above need not necess~rily all be provided by separate CA 0222~7~7 1997-12-24 WO 97/~3236g PCT/US96/10683 chei..ical sul)st~r~ces. For example, fluotitanic acid is well suited to be a single source of both titanium and fluoride.
A process according to the present invention for treating the surface of alu,~ ir~uUS metals characL~:rislically cGm~lJri es the fo", IdliOI- thereon of a coat-ing by bringing the surface of aluminiferous metal into colllduL, at a temperature from normal ambient temperature (i.e., at least 10 and more often at least 20 ~C) to 80 ~C, with a surface treatment working composition, and thereafter subjecting the surface of the aluminiferous metal carrying the surface treatment bath to a rinse with water and, usually, dlying, often with the use of heat.
~o Detailed Descriotion of the Invention, Including Preferred Embodiments The source of the phosphate ions for a concentrate or working cGr"posi-tion accc rJiny to the present invention can be one or more sele~;lio"s from ortho-phospl ,oric acid (i.e., H3PO4) and neutral and acid salts thereof and condensedphosphoric acids, such as pyrophosphoric acid (i.e., H4P2O7) and tripolyphos-phoric acid (i.e., H5P30,o) and neutral and acid salts of any of these. The par~cu-lar phosphate ions source selectecl is not critical, and the stoichiG"~l,ic equiv-alent as phosphdle ions from any of these sources is considered to be phosphale ions for deter",i"i"y whether a composition is according to the invention and ifsc, what its degree of pr~fer~nce is, irrespective of the actual extent of ionization and conde"salion to form che",ical species with P-O-P bonds that may exist in solution. The phospl-ate ions conl~, ll in a working bath accordi"y to the present invention is pr~rerdl~ly from 0.010 to 5.0 g/L, more preferably from 0.050 to 5.0 g/L, and even more prererdbly from 0.30 to 2.0 g/L. While a coating may be fommed even at a phosphate ions concentration below 0.010 g/L, such cGdlii)gs do not have an excellent corrosion resistance or paint adherence. The use of large conceY,I,dlions--in excess of 5.0 g/L --is uneconomical: While good-quality cGdlillgs are formed at such levels, no additional benefits are obtainedfrom the use of such large amounts, so that the cost of the treatment bath is raised without any offsetting benefit.
The source of the titanium containing substance(s) in a working or con-celllldle composition according to the present invention p,~r~3,dbly is either a salt COnlail lil Ig titanium and/or titanyl calions, the anions of which salt can be sulfate, CA 0222~7~7 l997-l2-24 fluoride, or the like, or fluotitanic acid or at least one of its salts, but the selection of the titanium containing substance(s) is not critical. The titanium containingsubstance(s) conce"l,dliG" in a surface treatment bath acco,-li"g to the invention should be from 0.010 to 2.0 g/L and is preferably from 0.10 to 2.0 g/L or more preferably from 0.10 to 1.0 g/L, in each instance c~lcul~t~d as titanium. The rap-id formation of a satisfactory cGdLil)g becomes quite problematic at a titanium content below 0.010 g/L. The use of large amounts--in excess of 2.0 g/L--is uneconomical: While good-qualit,v coali"gs are formed at such levels, no addi-tional benefits are obtained from the use of such large amounts and the cost of ~0 the treatment bath is raised.
The source of fluoride in the composition and surface treatment bath ac-cor~liny to the present invention can be such fluorine-containing acids as hydro-fluoric acid (i.e., HF), fluotitanic acid (i.e., H2TiF6), fluosilicic acid (i.e., H2SiFG), and fluo~ilconic acid (i.e., H2ZrF6), as well as any of their neutral and acid salts, but again the selection of the fluoride is not critical. The fluoride content in the surface treatment bath should be in the range from 0.010 to 12 g/L, preferably is from 0.050 to 5.0 g/L, and more ,orert:rably is from 0.10 to 3.0 g/L, in each case c~lGul~te~l as fluorine.
Aluminum ions eluting from the sut,~l,;ale are stabilized in the bath as aluminum fluoride by the fluoride, and the cGntenl levels given above include the quantity of fluoride necessz.ly to do this. Aluminum fluoride has little effect on the COdliny-rullllilly r~a~liGns. For exdn,~le~ a fluorine concenl~aliGI~ of about 0.2 g/L
is required in order to stabilize an aluminum concentration in the surface treat-ment bath of 0.1 g/L. Not counting the amount of fluorine required to produce aluminum fluoride, the optimal fluoride co, ll~3l)l for co~li"g fo", IdliOn iS from 0.010 to 5.0 g/L and preferably from 0.10 to 3.0 g/L, in each case C~lclll-t.eci as fluorine.
A fluorine cG"Ienl below 0.010 g/L results in an inadequate reactivity and hencein i"ade4.1ate coating ~or",dlion. On the other hand, levels in excess of 12 g/Lresult in an increased degree of etching that causes an undesirable unevenness in appearance, and such high levels also greatly complicate effluent treatment.
The ~ccelerator functions in a surface treatment process according to the present invention to accelerate the rate of formation of the titanium coating on CA 0222~7~7 1997-12-24 W<) 97~2369 PCT/US96/10683 the metal surface and also to induce the rc,lllldlion of a highly cor,osioll-resistant and strongly paint-adherent coating. The accelerator concenl,dliG" in the sur-face treatment bath must be in the range from 0.010 to 2.0 g/L and is preferablyin the range from 0.10 to 1.1 g/L. No z~cceleration of the film-forming reaction is usually observed at an ~ccelerator concentration below 0.010 g/L. The benefits from the accelerator do not further increase at accelerator levels in excess of 2.0 g/L, so that a.ldilio, Is in excess of this level simply raise costs and are thus un-economical.
An especially preferred ~Gcelerator includes at least one selection from the group co"sisli"g of nitrous acid, nitric acid, tungstic acid, molybdic acid, per-manganic acid, all water-soluble salts of all of these acids, and water-soluble or-ganoperoxides.
The nitrous acid/nitrite source is not critical as long as it is water-soluble;
however, the use of the sodium salt (i.e., NaNO2) or the potassium salt (i.e., KNO2) of nitrous acid is usually preferred bec~use of their relatively low cost.The nitric acid/nitrate source is also not critical, again as long as it is water-solu-ble; however, the use of the sodium salt (i.e., NaNO3) or the poPssiu~n salt (i.e., KNO3) of nitric acid (i.e., HNO3) or of nitric acid itself is pr~r~:ned bec~use of their relatively low cost.
The tungstic acid/tu"y~Ldle source is not critical as long as it is water-solu-ble; however, again the use of the sodium salt (i.e., Na2WO4) or potassi~rn salt(i.e., K2WO4) of tungstic acid is preferred because of their relatively low cost.
The molybdic acid/molybdate source is not critical as long as it is water-soluble; however, the use of the sodium salt (i.e., Na2MoO4) or ammonium salt (i.e., (NH4)6Mo7O24) of simple or condensed molybdic acid respectively is pre-ferred because of their relatively low cost.
The permanganic acid/permanganate selection is not critical as long as it is water-soluble; however, the use of the sodium salt (i.e., NaMnO4) or potas-sium salt (i.e., KMnO4) of pe, . . ,angar)ic acid is preferred bec~ ~ce of their relative-Iy low cost.
q rr~fer,ed examples of water-soluble organoperoxide are tert-butyl hydro-peroxide (i.e., (CH3)3C-O-OH), tert-hexyl hydroperoxide (i.e., CA 0222~7~7 1997-12-24 CH3CH2(CH3)2C-O-OH), and di-tert-butyl peroxide (i.e., (CH3)3C-O-O-C(CH3)3).
A working surface treal",enl bath according to the present invention is most conveniently prepared from a concentrate composition according to the present invention, and the pH of a working bath must be in the range from 1.0 to4.5. A pH below 1.0 cz~uses an excessive etch of the metal surface by the treat-ment bath and thereby strongly impairs film formation. It becomes very proble-matic to obtain a highly corrosion-resistant and strongly paint-adherent cGaLillg at a pH in excess of 4.5. The more preferred pH range is 1.3 to 3Ø The pH of the surface treatment bath accordi"g to the p~esenl invention can be adjusted byadding an acid, e.g., nitric acid, sulfuric acid, hydrofluoric acid, or the like to lower the pH, or by adding an alkali, e.g., sodium hydroxide, sodium carbonate, am-monium hydroxide, or the like to raise the pH.
When in the practice of the present invention the metal su6sl,ale is com-posed of an alloy of aluminum with copper or manganese, the stability of the s llt:alll,ent bath may be sl~l,sl~ulially impaired by fli-so!ution into the surface treat-ment bath of metal ions derived from the copper or ",al ,ganese alloying con ,pon-ent. In such a case, a difunctional organic acid or its alkali metal salt may beadded as metal sequesl~rins~ agent in order to cl ,elale the aro, ~r"enlio"ed alloy-ing metal ions. Examples of s~it~hl~ organic acids are gluconic acid, heptoglu-conic acid, oxalic acid, tartaric acid, and ethylenediaminelell aacetic acid.
A working surface l,eal",enl bath accordi"g to the pr~senl invention may be brought into contact with the suball dle to be ll ealed by any convenient meth-od and norrnally is used as part of a process sequence including other steps. A
preferred generalized process sequence, for example, is as follows:
25 1. Surface cleaning: degreasingwith an acidic, alkaline, orsolvent-based system 2. Water rinse 3. Surface l,eall"enl with treatment bath according to the present invention treatment temperature: ambient temperature to 80 ~C
treatment time: 0.5 to 60 seconds treatment technique: spraying or dipping 4. Water rinse -CA 0222~7~7 1997-12-24 W~ 97~0236g PCT/US9611O6X3 5. Rinse with deionized water 6. Drying.
A treatment process according to the present invention is performed by bringing a working surface treatment bath as described above into contact with a surface of aluminiferous metal at from room temperature to 80 ~C and prefer-ably at from 35 ~C to 70 ~C, for a contact time that is at least, with increasing preference in the order given, 0.50, 1.0, or 2.0 seconds and independently pref-erably is not more than, with increasing preference in the order given, 120, 90,60, 50, 40, 30, 20, 10, 8.0, 5.0, 3.0, or 2.5 seconds. Treatment times belo~ 0.5second are ~ssoc~tecl with an ins~,rricie"L l~:ac,Lion and hence may not yield the ro~ dliGn of a codlil-y with good cor,osion ~sisldnce and paint adherence. The properties of the coaLi~ l9 do not usually improve further at l,edl,nenL times above 120 seconds and in some instances do not improve further even after L,eal,l,e"L
tirnes of a few secGnds~ while any exle, .ded l. ~:dL I lel IL time inc~itases the process cost.
The CodLil l9 fo" "ed in a process accordi- ,9 to the invention prt:fé~ ~bly con-tains a mass per unit area of 3 to 50, or more preferably of 5 to 30, milligrams per square meter (hereir,drler usually abbreviated as "mg/m2") of titanium atoms, which are measured as such by some method, such as X-ray fluGrescerice, that iS indepe"de"L of the cl ,e" ,ical nature of the titanium atoms. When the surface codLin5~ mass is below 3 mg/m2 as titanium, there is usually i- ~ade4.1ate corrosion ,esi~lance by the resulting cGdlilly. At the other end of the range, there is usually an u,.saLisrdctory paint adherence by the coating when the coating weight ex-ceeds 50 mg/m2.
The alu. ";. ,irerous metals that may be subjected to surface treatment by a process according to the present invention encompass both pure aluminum and aluminum alloys, for example, Al-Cu, Al-Mn, Al-Mg, Al-Si, and Al-Zn alloys.
The form and dimensions of the aluminiferous metai used in the invention pro-cess are not critical, and, for example, sheet and various molding shapes fall within the scope of the process.
Surface treatment baths and process according to the present inventi~n will be Olu~LIdled in g,eater detail in the following through both working and com-CA 0222~7~7 1997-12-24 WO 97/02369 PCTtUS96/10683 parison examples.
Examples The l,~al."ent process sequence and other conditions outlined immediate-ly below apply to each of Examples 1 to 9 and Comparison Examples 1 to 7.
Sample material Aluminum-magnesium alloy sheet according to ~apanese Industrial Standard (hereinafter usually abbreviated as "JIS") 5182 was used.
Dimensions: 300 millimeters (hereinafter usually abbreviated as "mm") x 200 mm.
Sheetthickness: 0.25 mm Treatment conditions The conversion-treated sheet was prepared by the execution of the following processes in the sequence 1 - 2 - 3 ~ 4 - 5 - 6.
1. Degreasing (60 ~C, 10 seconds, spray) A 2 % aqueolJs solution of a cor""~ercially available alkaline degreaser, FlNECLEANER~)4377Kfrom Nihon Parkerizing CG~IIPallY, Limited, was used.
. Water rinse (ambient temperature, 10 seconds, spray) 3. Metal l,~dl".ent according to the invention or a comparison thereto (spray) The co".po,.ents used in the surface treatment baths, their concentra-tions in these baths, and the CG; Id;I;GI IS for the processes according to the inven-tion in Examples 1 to 9 and for CGI npariaol1 Examples 1 to 5 are shown in tables below. The surface l,~dl."enl conditions for Comparison Examples 6 and 7 are noted separ;dlely. An aqueouos solution of 40 % fluotitanic acid--a compound that is both a titanium containing substance(s) and a fluoride--was used in Examples 1, 4, 7, and 9 and in Comparison Example 2 as the source of both of these necess~ry components of a bath according to the invention. The entire amount of fluotitanic acid used is shown in the tables below under one column heading as a titanium source and under another heading as a fluoride source, but the amount was not in fact duplicated in the working bath. An aqueous solu-tion of 67.5 % nitric acid was used both as an ~ccelerator and for pH adjustment in Examples 1 and 5.
-CA 0222~7~7 1997-12-24 WC~) 47~236g PCT/US96/10683 4. Water rinse (ambient temperature, 10 seconds, spray) 5. Rinse with deionized water (ambient temperature, 5 seconds, spray) 6. Heating and drying (80 ~C, 3 minutes, hot-air oven) A small sprayer was used for the degreasing, water rinse, rinse with de-5 ionized water, and treatment accordi, ,9 to the invention or a comparison thereto.
The particular small sprayer used was designed to reproduce the same spraying conditions as in a continuous surface treatment line for the actual treatment ofaluminum alloy coil.
The following methods were used to test the coating weight, corrosion ~0 resistance, and paint adherence of the treated specimens.
(1) Coating Weight The Ti or Zr add-on, in mg/m2 on the treated sheet was measured using a lluorescent x-ray analyzer (RIX1000 from Rigaku Denki Kogyo Kabushiki Kai-sha).
15 (2) Corrosion resistance Salt-spray testing accordi"y to JIS Z 2371 was used to evaluate the cor-rosion resistance. The developr,lenl of conosiG~I on the Llt:dLed sheetwas visu-ally evz~4~ted after 150 hours of salt-spray testing, and the results were scored according to the fo"~ ;ng scale:
+ + + : corroded area was less than 10 %;
+ + : corroded area was greater than or equal to 10 %, but less than 50 %;
+ : corroded area was greater than or equal to 50 %, but less than 90 %;
X : corroded area was greater than or equal to 90 %.
(3) Paint adherence The surface of the conversion-ll~aLecl aluminum-lllagrlesium alloy sheet was painted with an epoxy-phenol paint for can lids to give a paint film thickness of 8 n ,icl u, l leters followed by baking for 3 minutes at 220 ~C. Polyamide film was 30 then inserted between two of these painted surfaces with hot-press bonding at200 ~C for 2 minutes. The hot-press bonded composite was cut into 10 mm wide x 120 mm long strips, which were the test specimens. A test specimen was CA 0222~7~7 l997-l2-24 peeled from the polyamide film using the T-peel test procedure, and the peel strength at this point was designated as the primary adherence. In order to eval-uate the durability of the adherence to water, a test specimen prepared as de-scribed above was dipped in boiling deionized water for 60 minutes and then submitted to measurement of the peel strength in the same T-peel test proced-ure. The result in this case was designated as the secondary adherence.
Larger values for the peel strength are indicative of a better paint adher-ence. A pe, rur" ,a"ce sufficient for practical applications was a peel strength of at least 7.0 kilograms-force (hereinafter usually abbreviated as "kg~')/10 mm width in the case of the primary adherence and a peel strength of at least 5.0 kgf/10 mm width in the case of the secondary adherence.
Comparison Example 6 The same treatment process was run as in Example 1, except for using a 2 % aqueous solution of a commercially available zirconium-based treatment agent, ALODINETM 4040 from Nihon Parkerizing Company, Limited, as the sur-face l,~dLn,e, t bath in process step 3. This treatment bath was sprayed on the same aluminum-magnesium alloy sheet as described above for 30 seconds at 40 ~C. The test results are reported in tables below.
Comparison Example 7 The same treatment was run as in Example 1, except for using a 2 %
aqueous solution of a commercially available zirconium-based l,~al")ent agent, ALODINETM 4040, from Nihon Parkerizing Company, Limited, as the treatment bath. This bath was sprayed on the same aluminum-magnesium alloy sheet as described above for 5 seconds at 40 ~C. The test results are reported in tables below.
Benefits of the Invention As the preceding description has made clear, application of a working treatment composition in a surface treatment process according to the present invention to aluminiferous metals rapidly forms a highly corrosion-resistant andstrongly paint-adherent coating on the metal surface prior to the painting or form-ing thereof. Moreover, when the substrate aluminiferous metal is in the form of continuous coil or sheet, rapidity of the treatment supports higher production line -wa, 97J0236g PCT/US96110683 speeds and permits compactness (space savings) of the treatment facilities.
In consequence of these effects, surface treatment concentrates, working baths, and processes according to the present invention for application to aluminiferous metals have a very high degree of practical utility.
~ Table 1 COMPONENTS USED IN THE TREATMENTS OF E)CAMPLES 1 TO 9 AND
CC~MPARISON EXAMPLES 1 TO 5, AND IDENTIFYING SYMBOLS THEREFOR
Cc~mponent Source Material(s) Compound Chemical Symbol Formula Pho~phate ions 85 % Orthophosphoric acid in waterH3PO4 a 40 % Fluotitanic acid in waterH2TiF6 A
Tit~nillrn g 24 % Titanic sulfate in waterTi(S04)2 B
sllbst~nce(s) Titanyl sulfate in water, 10 % TiTiOSO4 C
40 % Fluotitanic acid in waterH2TiF6 A
20 % Hydrofluoric acid in water HF a Fluoride 40 % Fluosilicic acid in waterH2SiF6 b 96 % Amrnonium acid fluoride in water NH4HF2 c 67.5 % Nitric Acid in water HNO3 T
PuLds~ perrn~ng~n~te KMnO4 U
97 % Pure Sodium Nitrite NaNO2 V
Ac~clcldLol Sodiurn tnng~t~te dihydrateNa2WO4- 2 H20 W
Ammonium heptarnolybdate (NH4)6M~7024 X
tetrahydrate ~ 4 H20 69 % Tert-butyl hy&op~,loxide in water (CH3)3C-O-OH y 5 % Stannic c~hlori~l~? in waterSnCl4 Z
67.5 % Nitric acid in water HNO3 T
pH Regulator 97 % Sulfi~ric acid in water H2SO4 a 25 % arnmonia in water NH40H b CA 0222~;7~;7 1997-12-24 Table 2 COMPOSITIONS OF SURFACE TREATMENT BATHS ACCORDING TO THE INVENTION
FYS~ Pl~ Grams perLiterin Bath of: pH pH
Number Regu- of Ti Com- Ph~ te Fluoride Accelerator lator Bath pound / Source/ Source/ Source/(Act- Type (Ti) (Po4-3) (F) ive Accelerat-or) 5.0 0f Al .O of a /5.0 of A /I .OO of T / T 1.3 / (0.58) (0.82) (1.39) (0.68) 2 2.00fC/ 0.20fa/ O.5ofa/ O.lOofW/ a 1.8 (0.20) (0.16) (0.10) (0.09) 3 30.00fB 4.00fa/ 15.00fa/ O.50ofV/ a 1.0 / (1.44) (3.30) (2.85) (0.49) 4 lO.OofA l.Oofa/ lO.OofA {I.OOofV/ b 1.5 / (1.17) (0.82) / (2.78)(0.97)} + {0.10 of U / (0.10)}
5 20.0 of B1.5 of a/ {0.5 of a/ {0.300f T/ T 1.3 /(0.96) (1.24) (0-10'} +(0.20)} + {0.05 {0.5 of b /of X / (0.05)}
(0.16) 6 5.0ofC/ I.Oofa/ 2.00fc/ {0.300f Y/ b 4.2 (0.48) (0.82) (1.28) (0-21)} + {0.10 of W / (0.10)}
ALUMINIFEROUS METALS
Technical Field This invention relates to a novel liquid surface l,t:dl",ent composition and process for application to aluminiferous metals, which provide the surface of aluminiferous metals, i.e., aluminum and aluminum alloys containing at least 65 % by weight of aluminum, with an exce"enl corrosion r~sisldnce and paint adher-ence. The pr~senl invention is applied with particularly good effect in the surface treatment of aluminum alloys in coil and sheet form.
Background Art Liquid cornposiliG"s, which hereinafter are often called "baths" for brevity, 0 even if used by some other method than immersionl that are in general use for treating the surface of alu,.,:. ,ir~r~ us metals can be broadly classiried into chrom-ate types and "o, Ic hrun Idte types. Chromic acid chromate conversion baths andphosphoric acid cl~,or"ale conversion baths are typical embodi",enL:, of chrom-ate type l,eal"~ent baths.
Chromic acid chrol "ate conversion baths came into prd~lical use in about 19~0 and are still widely used even at present for heat e,~cl ,a, .ger fln stock and aviation vehicle CGI I IpGi ~enl:j. The chr~, .,ic acid chromate conversion baths con-tain cl.r~,mic acid and fluoride as their main co,..ponents, with the fluoride func-tioning as a rtd-;tiOn ~cc~lerak~r. These baths coat metal surfaces with conver-20 sion codlillgs containing some quantity of hexavalent chromium.
Phosphoric acid cl.r~,-.ate conversion baths oliyindttd with the invention rljsr,loserl in United States Patent Number 2,438,877. These conversion baths, which couldi" ch"or.,ic acid, phospl)oric acid, and hydrofluoric acid as their main components, coat metal surfaces with conversion coatings whose main compon-25 ent is hydrated chromium pllosphale. Recallse these conversion codlil ,gs do notcol)l~in hexavalent chromium, they also are in wide use at present, for such ap-tions as underpaint coatings for beverage can body and lid stock. Neverth~less, since these chrur"dle type surface l,t:dl",ent baths do themselves contain toxic hexavalent cl,rol"ium even though the codli,)gs produced by them do not, CA 0222~7~7 1997-12-24 hexavalent chromium-free treatment baths are desired in view of the environ-mental problems from disposal of the baths, rinse waters, and the like.
Typical of the inventions in the field of the chromium-free nonchromate type surface treatment baths is the process disclosed in ~apanese Patent Appli-cation Laid Open EKokai or Unexamined} Number~;ho 52-~31937 [131,937/
1977]. The treatment bath in that reference consists of an acidic (pH approxi-mately 1.5 to 4.0) aqueous coating solution containing phosphate, fluoride, and zirconium or titanium or both. Treatment of the metal surface with this surface treatment bath forms thereon a protective coating whose main component is zir-~0 conium or titanium oxide. (This type of coating is often called a "conversion"
coating, bec~ e it is believed that it also con Ldil IS cations from the substrate in the form of oxides and/or phosphates.) An advantage of nonchromate surface treatment baths is that they are free of hexavalent cl ,romium, and this advantage has resulted in their wide use at the present time for treating the surface of drawn-and-ironed ("Dl") aluminum cans and the like. However, the nol ,cl ,ro" ,dle baths require longer lledll nel ll times for codli"y fc.l " ,dlion than cl ,ru, nale surface l",enl baths. Shortening surface treatment times has become an important issue in the last few years, because of the increasingly high line speeds being used to boost productivity. Moreover, nonchromate baths yield cGdlil,gs with a CGI l OSio" r~sislance and paint adherence inferior to those of c:hro" ,ate codlil lys.
The treatment process liiscloserl in Japanese Patent Application Laid Open [Kokai or Unexamined] Number Hei 1-246370 [246,370/1989l is an inven-tion whose object is to shorten the aforementioned surface treatment tirnes. In this process, the aluminiferous metal surface is first cleaned with an alkaline de-greaser and the cleaned surface is then treated with an acidic (pH 1.5 to 4.0) aqueous solution co,-l~i"ing 0.01 to 0.5 g/L of zirconium ions, 0.01 to 0.5 g/L of phosphate ions, 0.001 to 0.05 g/L, measured as its stoichiometric equivalent as fluorine atoms, of "free" fluoride ions, and optionally 0.01 to 1 g/L of vanadium ions. However, when this process is applied to Dl aluminum cans, the resulting film does not always have a satisfactory resistance to blackening.
Another nonchrur"ale l,edl"~ent process is rl j~clo5ed in Japanese Patent Publication Number Sho 57-39314 [39,314/1982]. Disclosecl therein is a treat-CA 0222~7~7 1997-12-24 wa~ 97102369 PCT/US96/10683 ment process in which the aluminiferous metal surface is treated with an acidic solution containing hydrogen peroxide, one or more selections from zirconium and titanium salts, and one or more selections from phosphoric acid and con-densed ,~ hosphoric acids. However, this treatment bath is ~-llsl b'~, and, in addi-tion, is also ir.~e~u~y rapid in terms of surface codli"g formation. Moreover, this document does not provide a specific descri~,Lion or disclosure of the treat-ment time, treatment temperature, or treatment process.
It is for these reasons that nonchromate tvpe surface treatment baths are at present almost never ùsed on surface treatment lines for aluminiferous metal ~o coil or sheet where short treatment times are critical.
In summary, then, there has yet to become established in the art a com-position or process for treating the surface of aluminiferous metals that can pro-vide short Ll't:dllllen~ times and is capable of for"~i"g a highly corrosion-resistant and strongly paint-adherent coaling, but is free of hexavalent cl ,run~ium.
Disclosure of the Invention Problemfs) to Be Solved by the Invention The pr~senL invention is dir~ ed to solving the problems .lescribed above for the prior art. In specific terms, the pr~:senl invention provides a composition and pr~cess for ll~dli.l~ the surface of aluminiferous metals that are able to form rapidly a very corrosion-resistant and highly paint-adherent coali"g on the sur-face of aluminiferous metals.
Summar,v of the Invention It has been discovered that a surface treatment composition containing dissolved phosphate ions, dissolved titanium containing substance(s), and dis-solved fluoride in particular relative quantities and a particular relative quantity of accelerator selechd from a specific group of chemical sub~ldnces can rapidly form a very cor,usion-resistant and highly paint-adherent coating on the surfaceof alun,i,,irt:,uus metals. The present invention was achieved based on this dis-covery.
A concenl,dle or working composition according to the present invention for treating the surface of aluminiferous metals characteristically comprises, preferably consists essentially of, or more preferably consists of, water and the CA 0222~7~7 1997-12-24 following materials in the relative proportions stated as follows: from 0.010 to 5 parts by weight of phosphate ions; from 0.010 to 2.0 parts by weight, C~ Gl ~lAted as its sloichiometric equivalent as titanium atoms, of dissolved titanium contain-ing substance(s); from 0.010 to 12 parts byweight, CAIClll~t~d as its stoichiomet-ric equivalent as fluorine atoms, of dissolved molecules and/or anions containing fluorine; and from 0.010 to 2.0 parts by weight of dissolved AGcelerator. The bases for the specification of these particular weight proportions for each com-ponent will be explained in sequence in the disc~ ~ssion of the composition of pre-ferred surface treatment baths, vide infr~. Cou"l~rio"s for the necess~y constit-~o uents e~pli -itly recited above are also necessAry if needed for ele.;l, ical neutral-ity.
The Accelerator incr~ases the speed of COdlil l9 rO~,,IdliOI I and is selected from the group consisling of oxyacids, such as tungstic acid (i.e., H2WO4), molyb-dic acid (i.e., HMoO3), permanganic acid (i.e., HMnO4), nitric acid (i.e., HNO3), nitrous acid (i.e., HNO2), hypochlorous acid (i.e., HCIO), chlorous acid (i.e., HCIO2), chloric acid (i.e., HC103), bromic acid (i.e., HBrO3), iodic acid (i.e., Hl03), perchloric acid (i.e., HC104), perbromic acid (i.e., HBrO4), periGclic acid (i.e, Hl04), orthopel iodic acid (i.e., H51O6), and salts of oxyacids; peroxoAcids, such aspe,~xo",oi,osulfuricacid (i.e., H2SO5), peruYodis~lfuricacid (i.e., H2S2O8), per-oxoll,o,lophosphoric acid (H3PO5), peroxodiphosphoric acid (i.e., H4P2O8), per-oxomonocarbonic acid (i.e., H2CO4), peroxodicarbonic acid (i.e., H2C2O6), and any of the per~xobGric acids (i.e., HBO3-1/2H20, HBO4-H20, or HBO5-H20), and salts of peroxoArids; higher valent metal cations of metals with at least two stable cationic valence states, in caliol-s that do not include oxygen, in aqueous so-lution, such as tetravalent cerium (i.e., Ce+4), trivalent iron (i.e., Fe+3), and tetra-valent tin (Sn4+); hydll,geo peroxide (H2O2); and water-soluble organoperoxides.The use of an accelerator selected from this group in a treatment composition according to the p resel-L invention yields a s~ ~hst~ntial improvement in the speed of fo" ~ IdLiOn of a sufficiently thick coating to have protective qualities and in the corrosion resistance and paint adherence of the coating thereby formed.
The four necessary active ingredients in a composition according to the invention as desc,iL,ed above need not necess~rily all be provided by separate CA 0222~7~7 1997-12-24 WO 97/~3236g PCT/US96/10683 chei..ical sul)st~r~ces. For example, fluotitanic acid is well suited to be a single source of both titanium and fluoride.
A process according to the present invention for treating the surface of alu,~ ir~uUS metals characL~:rislically cGm~lJri es the fo", IdliOI- thereon of a coat-ing by bringing the surface of aluminiferous metal into colllduL, at a temperature from normal ambient temperature (i.e., at least 10 and more often at least 20 ~C) to 80 ~C, with a surface treatment working composition, and thereafter subjecting the surface of the aluminiferous metal carrying the surface treatment bath to a rinse with water and, usually, dlying, often with the use of heat.
~o Detailed Descriotion of the Invention, Including Preferred Embodiments The source of the phosphate ions for a concentrate or working cGr"posi-tion accc rJiny to the present invention can be one or more sele~;lio"s from ortho-phospl ,oric acid (i.e., H3PO4) and neutral and acid salts thereof and condensedphosphoric acids, such as pyrophosphoric acid (i.e., H4P2O7) and tripolyphos-phoric acid (i.e., H5P30,o) and neutral and acid salts of any of these. The par~cu-lar phosphate ions source selectecl is not critical, and the stoichiG"~l,ic equiv-alent as phosphdle ions from any of these sources is considered to be phosphale ions for deter",i"i"y whether a composition is according to the invention and ifsc, what its degree of pr~fer~nce is, irrespective of the actual extent of ionization and conde"salion to form che",ical species with P-O-P bonds that may exist in solution. The phospl-ate ions conl~, ll in a working bath accordi"y to the present invention is pr~rerdl~ly from 0.010 to 5.0 g/L, more preferably from 0.050 to 5.0 g/L, and even more prererdbly from 0.30 to 2.0 g/L. While a coating may be fommed even at a phosphate ions concentration below 0.010 g/L, such cGdlii)gs do not have an excellent corrosion resistance or paint adherence. The use of large conceY,I,dlions--in excess of 5.0 g/L --is uneconomical: While good-quality cGdlillgs are formed at such levels, no additional benefits are obtainedfrom the use of such large amounts, so that the cost of the treatment bath is raised without any offsetting benefit.
The source of the titanium containing substance(s) in a working or con-celllldle composition according to the present invention p,~r~3,dbly is either a salt COnlail lil Ig titanium and/or titanyl calions, the anions of which salt can be sulfate, CA 0222~7~7 l997-l2-24 fluoride, or the like, or fluotitanic acid or at least one of its salts, but the selection of the titanium containing substance(s) is not critical. The titanium containingsubstance(s) conce"l,dliG" in a surface treatment bath acco,-li"g to the invention should be from 0.010 to 2.0 g/L and is preferably from 0.10 to 2.0 g/L or more preferably from 0.10 to 1.0 g/L, in each instance c~lcul~t~d as titanium. The rap-id formation of a satisfactory cGdLil)g becomes quite problematic at a titanium content below 0.010 g/L. The use of large amounts--in excess of 2.0 g/L--is uneconomical: While good-qualit,v coali"gs are formed at such levels, no addi-tional benefits are obtained from the use of such large amounts and the cost of ~0 the treatment bath is raised.
The source of fluoride in the composition and surface treatment bath ac-cor~liny to the present invention can be such fluorine-containing acids as hydro-fluoric acid (i.e., HF), fluotitanic acid (i.e., H2TiF6), fluosilicic acid (i.e., H2SiFG), and fluo~ilconic acid (i.e., H2ZrF6), as well as any of their neutral and acid salts, but again the selection of the fluoride is not critical. The fluoride content in the surface treatment bath should be in the range from 0.010 to 12 g/L, preferably is from 0.050 to 5.0 g/L, and more ,orert:rably is from 0.10 to 3.0 g/L, in each case c~lGul~te~l as fluorine.
Aluminum ions eluting from the sut,~l,;ale are stabilized in the bath as aluminum fluoride by the fluoride, and the cGntenl levels given above include the quantity of fluoride necessz.ly to do this. Aluminum fluoride has little effect on the COdliny-rullllilly r~a~liGns. For exdn,~le~ a fluorine concenl~aliGI~ of about 0.2 g/L
is required in order to stabilize an aluminum concentration in the surface treat-ment bath of 0.1 g/L. Not counting the amount of fluorine required to produce aluminum fluoride, the optimal fluoride co, ll~3l)l for co~li"g fo", IdliOn iS from 0.010 to 5.0 g/L and preferably from 0.10 to 3.0 g/L, in each case C~lclll-t.eci as fluorine.
A fluorine cG"Ienl below 0.010 g/L results in an inadequate reactivity and hencein i"ade4.1ate coating ~or",dlion. On the other hand, levels in excess of 12 g/Lresult in an increased degree of etching that causes an undesirable unevenness in appearance, and such high levels also greatly complicate effluent treatment.
The ~ccelerator functions in a surface treatment process according to the present invention to accelerate the rate of formation of the titanium coating on CA 0222~7~7 1997-12-24 W<) 97~2369 PCT/US96/10683 the metal surface and also to induce the rc,lllldlion of a highly cor,osioll-resistant and strongly paint-adherent coating. The accelerator concenl,dliG" in the sur-face treatment bath must be in the range from 0.010 to 2.0 g/L and is preferablyin the range from 0.10 to 1.1 g/L. No z~cceleration of the film-forming reaction is usually observed at an ~ccelerator concentration below 0.010 g/L. The benefits from the accelerator do not further increase at accelerator levels in excess of 2.0 g/L, so that a.ldilio, Is in excess of this level simply raise costs and are thus un-economical.
An especially preferred ~Gcelerator includes at least one selection from the group co"sisli"g of nitrous acid, nitric acid, tungstic acid, molybdic acid, per-manganic acid, all water-soluble salts of all of these acids, and water-soluble or-ganoperoxides.
The nitrous acid/nitrite source is not critical as long as it is water-soluble;
however, the use of the sodium salt (i.e., NaNO2) or the potassium salt (i.e., KNO2) of nitrous acid is usually preferred bec~use of their relatively low cost.The nitric acid/nitrate source is also not critical, again as long as it is water-solu-ble; however, the use of the sodium salt (i.e., NaNO3) or the poPssiu~n salt (i.e., KNO3) of nitric acid (i.e., HNO3) or of nitric acid itself is pr~r~:ned bec~use of their relatively low cost.
The tungstic acid/tu"y~Ldle source is not critical as long as it is water-solu-ble; however, again the use of the sodium salt (i.e., Na2WO4) or potassi~rn salt(i.e., K2WO4) of tungstic acid is preferred because of their relatively low cost.
The molybdic acid/molybdate source is not critical as long as it is water-soluble; however, the use of the sodium salt (i.e., Na2MoO4) or ammonium salt (i.e., (NH4)6Mo7O24) of simple or condensed molybdic acid respectively is pre-ferred because of their relatively low cost.
The permanganic acid/permanganate selection is not critical as long as it is water-soluble; however, the use of the sodium salt (i.e., NaMnO4) or potas-sium salt (i.e., KMnO4) of pe, . . ,angar)ic acid is preferred bec~ ~ce of their relative-Iy low cost.
q rr~fer,ed examples of water-soluble organoperoxide are tert-butyl hydro-peroxide (i.e., (CH3)3C-O-OH), tert-hexyl hydroperoxide (i.e., CA 0222~7~7 1997-12-24 CH3CH2(CH3)2C-O-OH), and di-tert-butyl peroxide (i.e., (CH3)3C-O-O-C(CH3)3).
A working surface treal",enl bath according to the present invention is most conveniently prepared from a concentrate composition according to the present invention, and the pH of a working bath must be in the range from 1.0 to4.5. A pH below 1.0 cz~uses an excessive etch of the metal surface by the treat-ment bath and thereby strongly impairs film formation. It becomes very proble-matic to obtain a highly corrosion-resistant and strongly paint-adherent cGaLillg at a pH in excess of 4.5. The more preferred pH range is 1.3 to 3Ø The pH of the surface treatment bath accordi"g to the p~esenl invention can be adjusted byadding an acid, e.g., nitric acid, sulfuric acid, hydrofluoric acid, or the like to lower the pH, or by adding an alkali, e.g., sodium hydroxide, sodium carbonate, am-monium hydroxide, or the like to raise the pH.
When in the practice of the present invention the metal su6sl,ale is com-posed of an alloy of aluminum with copper or manganese, the stability of the s llt:alll,ent bath may be sl~l,sl~ulially impaired by fli-so!ution into the surface treat-ment bath of metal ions derived from the copper or ",al ,ganese alloying con ,pon-ent. In such a case, a difunctional organic acid or its alkali metal salt may beadded as metal sequesl~rins~ agent in order to cl ,elale the aro, ~r"enlio"ed alloy-ing metal ions. Examples of s~it~hl~ organic acids are gluconic acid, heptoglu-conic acid, oxalic acid, tartaric acid, and ethylenediaminelell aacetic acid.
A working surface l,eal",enl bath accordi"g to the pr~senl invention may be brought into contact with the suball dle to be ll ealed by any convenient meth-od and norrnally is used as part of a process sequence including other steps. A
preferred generalized process sequence, for example, is as follows:
25 1. Surface cleaning: degreasingwith an acidic, alkaline, orsolvent-based system 2. Water rinse 3. Surface l,eall"enl with treatment bath according to the present invention treatment temperature: ambient temperature to 80 ~C
treatment time: 0.5 to 60 seconds treatment technique: spraying or dipping 4. Water rinse -CA 0222~7~7 1997-12-24 W~ 97~0236g PCT/US9611O6X3 5. Rinse with deionized water 6. Drying.
A treatment process according to the present invention is performed by bringing a working surface treatment bath as described above into contact with a surface of aluminiferous metal at from room temperature to 80 ~C and prefer-ably at from 35 ~C to 70 ~C, for a contact time that is at least, with increasing preference in the order given, 0.50, 1.0, or 2.0 seconds and independently pref-erably is not more than, with increasing preference in the order given, 120, 90,60, 50, 40, 30, 20, 10, 8.0, 5.0, 3.0, or 2.5 seconds. Treatment times belo~ 0.5second are ~ssoc~tecl with an ins~,rricie"L l~:ac,Lion and hence may not yield the ro~ dliGn of a codlil-y with good cor,osion ~sisldnce and paint adherence. The properties of the coaLi~ l9 do not usually improve further at l,edl,nenL times above 120 seconds and in some instances do not improve further even after L,eal,l,e"L
tirnes of a few secGnds~ while any exle, .ded l. ~:dL I lel IL time inc~itases the process cost.
The CodLil l9 fo" "ed in a process accordi- ,9 to the invention prt:fé~ ~bly con-tains a mass per unit area of 3 to 50, or more preferably of 5 to 30, milligrams per square meter (hereir,drler usually abbreviated as "mg/m2") of titanium atoms, which are measured as such by some method, such as X-ray fluGrescerice, that iS indepe"de"L of the cl ,e" ,ical nature of the titanium atoms. When the surface codLin5~ mass is below 3 mg/m2 as titanium, there is usually i- ~ade4.1ate corrosion ,esi~lance by the resulting cGdlilly. At the other end of the range, there is usually an u,.saLisrdctory paint adherence by the coating when the coating weight ex-ceeds 50 mg/m2.
The alu. ";. ,irerous metals that may be subjected to surface treatment by a process according to the present invention encompass both pure aluminum and aluminum alloys, for example, Al-Cu, Al-Mn, Al-Mg, Al-Si, and Al-Zn alloys.
The form and dimensions of the aluminiferous metai used in the invention pro-cess are not critical, and, for example, sheet and various molding shapes fall within the scope of the process.
Surface treatment baths and process according to the present inventi~n will be Olu~LIdled in g,eater detail in the following through both working and com-CA 0222~7~7 1997-12-24 WO 97/02369 PCTtUS96/10683 parison examples.
Examples The l,~al."ent process sequence and other conditions outlined immediate-ly below apply to each of Examples 1 to 9 and Comparison Examples 1 to 7.
Sample material Aluminum-magnesium alloy sheet according to ~apanese Industrial Standard (hereinafter usually abbreviated as "JIS") 5182 was used.
Dimensions: 300 millimeters (hereinafter usually abbreviated as "mm") x 200 mm.
Sheetthickness: 0.25 mm Treatment conditions The conversion-treated sheet was prepared by the execution of the following processes in the sequence 1 - 2 - 3 ~ 4 - 5 - 6.
1. Degreasing (60 ~C, 10 seconds, spray) A 2 % aqueolJs solution of a cor""~ercially available alkaline degreaser, FlNECLEANER~)4377Kfrom Nihon Parkerizing CG~IIPallY, Limited, was used.
. Water rinse (ambient temperature, 10 seconds, spray) 3. Metal l,~dl".ent according to the invention or a comparison thereto (spray) The co".po,.ents used in the surface treatment baths, their concentra-tions in these baths, and the CG; Id;I;GI IS for the processes according to the inven-tion in Examples 1 to 9 and for CGI npariaol1 Examples 1 to 5 are shown in tables below. The surface l,~dl."enl conditions for Comparison Examples 6 and 7 are noted separ;dlely. An aqueouos solution of 40 % fluotitanic acid--a compound that is both a titanium containing substance(s) and a fluoride--was used in Examples 1, 4, 7, and 9 and in Comparison Example 2 as the source of both of these necess~ry components of a bath according to the invention. The entire amount of fluotitanic acid used is shown in the tables below under one column heading as a titanium source and under another heading as a fluoride source, but the amount was not in fact duplicated in the working bath. An aqueous solu-tion of 67.5 % nitric acid was used both as an ~ccelerator and for pH adjustment in Examples 1 and 5.
-CA 0222~7~7 1997-12-24 WC~) 47~236g PCT/US96/10683 4. Water rinse (ambient temperature, 10 seconds, spray) 5. Rinse with deionized water (ambient temperature, 5 seconds, spray) 6. Heating and drying (80 ~C, 3 minutes, hot-air oven) A small sprayer was used for the degreasing, water rinse, rinse with de-5 ionized water, and treatment accordi, ,9 to the invention or a comparison thereto.
The particular small sprayer used was designed to reproduce the same spraying conditions as in a continuous surface treatment line for the actual treatment ofaluminum alloy coil.
The following methods were used to test the coating weight, corrosion ~0 resistance, and paint adherence of the treated specimens.
(1) Coating Weight The Ti or Zr add-on, in mg/m2 on the treated sheet was measured using a lluorescent x-ray analyzer (RIX1000 from Rigaku Denki Kogyo Kabushiki Kai-sha).
15 (2) Corrosion resistance Salt-spray testing accordi"y to JIS Z 2371 was used to evaluate the cor-rosion resistance. The developr,lenl of conosiG~I on the Llt:dLed sheetwas visu-ally evz~4~ted after 150 hours of salt-spray testing, and the results were scored according to the fo"~ ;ng scale:
+ + + : corroded area was less than 10 %;
+ + : corroded area was greater than or equal to 10 %, but less than 50 %;
+ : corroded area was greater than or equal to 50 %, but less than 90 %;
X : corroded area was greater than or equal to 90 %.
(3) Paint adherence The surface of the conversion-ll~aLecl aluminum-lllagrlesium alloy sheet was painted with an epoxy-phenol paint for can lids to give a paint film thickness of 8 n ,icl u, l leters followed by baking for 3 minutes at 220 ~C. Polyamide film was 30 then inserted between two of these painted surfaces with hot-press bonding at200 ~C for 2 minutes. The hot-press bonded composite was cut into 10 mm wide x 120 mm long strips, which were the test specimens. A test specimen was CA 0222~7~7 l997-l2-24 peeled from the polyamide film using the T-peel test procedure, and the peel strength at this point was designated as the primary adherence. In order to eval-uate the durability of the adherence to water, a test specimen prepared as de-scribed above was dipped in boiling deionized water for 60 minutes and then submitted to measurement of the peel strength in the same T-peel test proced-ure. The result in this case was designated as the secondary adherence.
Larger values for the peel strength are indicative of a better paint adher-ence. A pe, rur" ,a"ce sufficient for practical applications was a peel strength of at least 7.0 kilograms-force (hereinafter usually abbreviated as "kg~')/10 mm width in the case of the primary adherence and a peel strength of at least 5.0 kgf/10 mm width in the case of the secondary adherence.
Comparison Example 6 The same treatment process was run as in Example 1, except for using a 2 % aqueous solution of a commercially available zirconium-based treatment agent, ALODINETM 4040 from Nihon Parkerizing Company, Limited, as the sur-face l,~dLn,e, t bath in process step 3. This treatment bath was sprayed on the same aluminum-magnesium alloy sheet as described above for 30 seconds at 40 ~C. The test results are reported in tables below.
Comparison Example 7 The same treatment was run as in Example 1, except for using a 2 %
aqueous solution of a commercially available zirconium-based l,~al")ent agent, ALODINETM 4040, from Nihon Parkerizing Company, Limited, as the treatment bath. This bath was sprayed on the same aluminum-magnesium alloy sheet as described above for 5 seconds at 40 ~C. The test results are reported in tables below.
Benefits of the Invention As the preceding description has made clear, application of a working treatment composition in a surface treatment process according to the present invention to aluminiferous metals rapidly forms a highly corrosion-resistant andstrongly paint-adherent coating on the metal surface prior to the painting or form-ing thereof. Moreover, when the substrate aluminiferous metal is in the form of continuous coil or sheet, rapidity of the treatment supports higher production line -wa, 97J0236g PCT/US96110683 speeds and permits compactness (space savings) of the treatment facilities.
In consequence of these effects, surface treatment concentrates, working baths, and processes according to the present invention for application to aluminiferous metals have a very high degree of practical utility.
~ Table 1 COMPONENTS USED IN THE TREATMENTS OF E)CAMPLES 1 TO 9 AND
CC~MPARISON EXAMPLES 1 TO 5, AND IDENTIFYING SYMBOLS THEREFOR
Cc~mponent Source Material(s) Compound Chemical Symbol Formula Pho~phate ions 85 % Orthophosphoric acid in waterH3PO4 a 40 % Fluotitanic acid in waterH2TiF6 A
Tit~nillrn g 24 % Titanic sulfate in waterTi(S04)2 B
sllbst~nce(s) Titanyl sulfate in water, 10 % TiTiOSO4 C
40 % Fluotitanic acid in waterH2TiF6 A
20 % Hydrofluoric acid in water HF a Fluoride 40 % Fluosilicic acid in waterH2SiF6 b 96 % Amrnonium acid fluoride in water NH4HF2 c 67.5 % Nitric Acid in water HNO3 T
PuLds~ perrn~ng~n~te KMnO4 U
97 % Pure Sodium Nitrite NaNO2 V
Ac~clcldLol Sodiurn tnng~t~te dihydrateNa2WO4- 2 H20 W
Ammonium heptarnolybdate (NH4)6M~7024 X
tetrahydrate ~ 4 H20 69 % Tert-butyl hy&op~,loxide in water (CH3)3C-O-OH y 5 % Stannic c~hlori~l~? in waterSnCl4 Z
67.5 % Nitric acid in water HNO3 T
pH Regulator 97 % Sulfi~ric acid in water H2SO4 a 25 % arnmonia in water NH40H b CA 0222~;7~;7 1997-12-24 Table 2 COMPOSITIONS OF SURFACE TREATMENT BATHS ACCORDING TO THE INVENTION
FYS~ Pl~ Grams perLiterin Bath of: pH pH
Number Regu- of Ti Com- Ph~ te Fluoride Accelerator lator Bath pound / Source/ Source/ Source/(Act- Type (Ti) (Po4-3) (F) ive Accelerat-or) 5.0 0f Al .O of a /5.0 of A /I .OO of T / T 1.3 / (0.58) (0.82) (1.39) (0.68) 2 2.00fC/ 0.20fa/ O.5ofa/ O.lOofW/ a 1.8 (0.20) (0.16) (0.10) (0.09) 3 30.00fB 4.00fa/ 15.00fa/ O.50ofV/ a 1.0 / (1.44) (3.30) (2.85) (0.49) 4 lO.OofA l.Oofa/ lO.OofA {I.OOofV/ b 1.5 / (1.17) (0.82) / (2.78)(0.97)} + {0.10 of U / (0.10)}
5 20.0 of B1.5 of a/ {0.5 of a/ {0.300f T/ T 1.3 /(0.96) (1.24) (0-10'} +(0.20)} + {0.05 {0.5 of b /of X / (0.05)}
(0.16) 6 5.0ofC/ I.Oofa/ 2.00fc/ {0.300f Y/ b 4.2 (0.48) (0.82) (1.28) (0-21)} + {0.10 of W / (0.10)}
7 {0.300f 2.50fa/ {3.00f A l.OofY/ b 2.5 A/ (2.06) /(0.83)} + (0.69) (0-35)} + {2.0 of c /
{5-0 of C (1.28)}
/ (0-50)}
{5-0 of C (1.28)}
/ (0-50)}
8 l.OofB/ 0.040fa/ 0.20fb/ 0.03 of U/ b 4.0 (0.05) (0.03) (0.06) (0.03) 9 2.00fA/ 0.50fa/ 2.00fA/ 3.000fZ/ a 1.6 (0.23) (0.41) (0.56) (0.15) W~ 97102369 PCT/US96~10683 Table 3 COMPOSITIONS OF SURFACE TREATMENT BATHS FOR COMPARISON EXAMPLES
C~mpar- Grams per Liter in Bath of: pH pH
lison Regu- of FY~ rle Ti Com- Ph~s, ~-- FluorideAccele.. lor lator Bath Numberpound / Source / Source /Source / (Act- Type (Ti) (po4-3) (F) iveAccelerat-or) none 1.0 of a /0.5 of b /1.00 of V / a 1.3 (0.82) (0. 1 6) (0.97) 2 5.0 of A / none 5.0 of A /0.30 of W / b 1.6 (0.58) (1.39) (0.27) 3 10.0 of C /1.5 of a / none 1.0 of Y / a 1.2 (1.00) (1.24) (0.69) 4 30.0OfB/ 4.0Ofa/ 5.0Ofa/ O.SofV/ b 5.0 (1.44) (3.30) (0.95) (0.49) 10.0 of B /1.0 of a /5.0 of a / none b 1 .S
(0.48) (0.82) (0.95) Table 4 PROCESS CONDITIONS AND EVALUATION TEST RESULTS
FY~ ~r~Co-~itinns During Add-on Rating Paint ~ , F~, ("Ex") or Tr~r t Acco. .li~.g Mass of after 150 kgf/10 mm of Width Compar-to the Invention or Ti, mg/m2Hour Salt ison Ex-Comparison Spray ("CE") Temper- Contact Test PrimarySecondary Number ature, ~C Time, Seconds Exl 40 6 15 +++ 10.8 8.3 Ex 2 45 40 20 + + + 9.4 6.7 Ex3 40 5 12 +++ 9.0 6.7 Ex4 65 2 15 +++ 11.4 9.2 Ex 5 35 5 4.5 + + + 10.5 9.0 Ex6 45 8 43 +++ 9.3 6.8 Ex 7 60 4 25 + + + 8.9 7.8 Ex 8 35 50 9.0 + + + 7.5 5.3 Ex 9 50 12 20 + + + 7.2 5.5 CE 1 50 10 0 x 3.8 1.0 CE 2 55 5 20 + 6.0 2.9 CE 3 35 40 1.0 x 4.0 1.3 CE 4 45 8 17 + + 5.2 3.4 CE 5 60 30 2.0 x 5.0 1.3 CE6 40 30 *18OfZr ++ 7.2 5.0 CE 7 40 5 *5 of Zr + 4.6 2.7 Footnote for Table 4 *There is no titanium added on in these co,llp~uison examples, which used a l.Gal...~ c-~...posilion that does not contain th~nillm
C~mpar- Grams per Liter in Bath of: pH pH
lison Regu- of FY~ rle Ti Com- Ph~s, ~-- FluorideAccele.. lor lator Bath Numberpound / Source / Source /Source / (Act- Type (Ti) (po4-3) (F) iveAccelerat-or) none 1.0 of a /0.5 of b /1.00 of V / a 1.3 (0.82) (0. 1 6) (0.97) 2 5.0 of A / none 5.0 of A /0.30 of W / b 1.6 (0.58) (1.39) (0.27) 3 10.0 of C /1.5 of a / none 1.0 of Y / a 1.2 (1.00) (1.24) (0.69) 4 30.0OfB/ 4.0Ofa/ 5.0Ofa/ O.SofV/ b 5.0 (1.44) (3.30) (0.95) (0.49) 10.0 of B /1.0 of a /5.0 of a / none b 1 .S
(0.48) (0.82) (0.95) Table 4 PROCESS CONDITIONS AND EVALUATION TEST RESULTS
FY~ ~r~Co-~itinns During Add-on Rating Paint ~ , F~, ("Ex") or Tr~r t Acco. .li~.g Mass of after 150 kgf/10 mm of Width Compar-to the Invention or Ti, mg/m2Hour Salt ison Ex-Comparison Spray ("CE") Temper- Contact Test PrimarySecondary Number ature, ~C Time, Seconds Exl 40 6 15 +++ 10.8 8.3 Ex 2 45 40 20 + + + 9.4 6.7 Ex3 40 5 12 +++ 9.0 6.7 Ex4 65 2 15 +++ 11.4 9.2 Ex 5 35 5 4.5 + + + 10.5 9.0 Ex6 45 8 43 +++ 9.3 6.8 Ex 7 60 4 25 + + + 8.9 7.8 Ex 8 35 50 9.0 + + + 7.5 5.3 Ex 9 50 12 20 + + + 7.2 5.5 CE 1 50 10 0 x 3.8 1.0 CE 2 55 5 20 + 6.0 2.9 CE 3 35 40 1.0 x 4.0 1.3 CE 4 45 8 17 + + 5.2 3.4 CE 5 60 30 2.0 x 5.0 1.3 CE6 40 30 *18OfZr ++ 7.2 5.0 CE 7 40 5 *5 of Zr + 4.6 2.7 Footnote for Table 4 *There is no titanium added on in these co,llp~uison examples, which used a l.Gal...~ c-~...posilion that does not contain th~nillm
Claims (10)
1. An aqueous liquid composition that is suitable as such, and is therefore a working composition, or after dilution with additional water, and is therefore a concentrate composition, for treating the surface of aluminiferous metals to form a corrosion protective and paint-adherent coating thereon, said composition comprising the following components in relative amounts as recited below:
(A) from 0.01 to 5 parts by weight of dissolved phosphate ions;
(B) from 0.01 to 2 parts by weight, calculated as their stoichiometric equivalent as titanium atoms, of dissolved molecules, ions, or both that contain titanium atoms;
(C) from 0.01 to 12 parts by weight, calculated as their stoichiometric equivalent as fluorine atoms, of dissolved molecules, anions, or both that contain fluorine atoms; and (D) from 0.01 to 2 parts by weight of accelerator.
(A) from 0.01 to 5 parts by weight of dissolved phosphate ions;
(B) from 0.01 to 2 parts by weight, calculated as their stoichiometric equivalent as titanium atoms, of dissolved molecules, ions, or both that contain titanium atoms;
(C) from 0.01 to 12 parts by weight, calculated as their stoichiometric equivalent as fluorine atoms, of dissolved molecules, anions, or both that contain fluorine atoms; and (D) from 0.01 to 2 parts by weight of accelerator.
2. A composition according to claim 1, wherein the accelerator comprises at least one material selected from the group consisting of nitrous acid, tungstic acid, molybdic acid, permanganic acid, water-soluble salts of all of the preceding acids, and water-soluble organoperoxides, and, optionally, also contains nitrateions.
3. A working composition according to claim 2, wherein the composition has a pH from 1.0 to 4.5 and contains from 0.01 to 5 g/L of dissolved phosphate ions, from 0.01 to 2 g/L, calculated as titanium atoms, of dissolved molecules, ions, or both that contain titanium atoms; from 0.01 to 12 g/L, calculated as fluorine atoms, of dissolved molecules, anions, or both that contain fluorine atoms; and 0.01 to 2 g/L of accelerator.
4. A working composition according to claim 3, wherein the composition contains from 0.05 to 5 g/L of dissolved phosphate ions, from 0.10 to 2 g/L, calculated as titanium atoms, of dissolved molecules, ions, or both that containtitanium atoms; and from 0.05 to 5.0 g/L, calculated as fluorine atoms, of dissolved molecules, anions, or both that contain fluorine atoms; and the accelerator is selected from the group consisting of nitrous acid, nitric acid, tungstic acid, molybdic acid, permanganic acid, water soluble salts of all of the preceding acids, and water-soluble organoperoxides.
5. A working composition according to claim 4, wherein the composition has a pH from 1.3 to 3.0 and contains from 0.30 to 2.0 g/L of dissolved phosphate ions, from 0.10 to 1.0 g/L, calculated as titanium atoms, of dissolvedmolecules, ions, or both that contain titanium atoms; from 0.10 to 2.0 g/L, calculated as fluorine atoms, of dissolved molecules, anions, or both that contain fluorineatoms; and from 0.10 to 1.1 g.L of accelerator.
6. A working composition according to claim 1, wherein the composition has a pH from 1.0 to 4.5 and contains from 0.01 to 5 g/L of dissolved phosphate ions; from 0.01 to 2 g/L, calculated as titanium atoms, of dissolved molecules, ions, or both that contain titanium atoms; from 0.01 to 12 g/L, calculated as fluorine atoms, of dissolved molecules, anions, or both that contain fluorine atoms; and 0.01 to 2 g/L of accelerator.
7. A working composition according to claim 6, wherein the composition contains from 0.05 to 5 g/L of dissolved phosphate ions; from 0.10 to 2 g/L, calculated as titanium atoms, of dissolved molecules, ions, or both that containtitanium atoms; and from 0.05 to 5.0 g/L, calculated as fluorine atoms, of dissolved molecules, anions, or both that contain fluorine atoms; and the accelerator is selected from the group consisting of nitrous acid, nitric acid, tungstic acid, molybdic acid, permanganic acid, water soluble salts of all of the preceding acids, and water-soluble organoperoxides.
8. A working composition according to claim 7, wherein the composition has a pH from 1.3 to 3.0 and contains from 0.30 to 2.0 g/L of dissolved phosphate ions; from 0.10 to 1.2 g/L, calculated as titanium atoms, of dissolvedmolecules, ions, or both that contain titanium atoms; from 0.10 to 2.8 g/L, calculated as fluorine atoms, of dissolved molecules, anions, or both that contain fluorineatoms; and from 0.10 to 1.1 g.L of accelerator.
9. A process for treating an aluminiferous metal surface, said process comprising steps of:
(I) bringing the aluminiferous metal surface into contact, at a temperature from normal ambient temperature to 80 °C, with a working composition according to any one of claims 3 to 8 for a time of at least 0.5 second;
and (II) discontinuing the contact established in step (I) and thereafter subjecting the aluminiferous metal surface carrying residue of the surface treatment bath to a rinse with water; and, optionally, (III) drying the rinsed surface from the end of step (II).
(I) bringing the aluminiferous metal surface into contact, at a temperature from normal ambient temperature to 80 °C, with a working composition according to any one of claims 3 to 8 for a time of at least 0.5 second;
and (II) discontinuing the contact established in step (I) and thereafter subjecting the aluminiferous metal surface carrying residue of the surface treatment bath to a rinse with water; and, optionally, (III) drying the rinsed surface from the end of step (II).
10. A process according to claim 9, wherein a coating weight of from 3 to 50 mg/m2 calculated as titanium is produced on the aluminiferous metal surface during the process.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16624395A JP3623015B2 (en) | 1995-06-30 | 1995-06-30 | Surface treatment liquid for aluminum-containing metal material and surface treatment method |
| JP7/166,243 | 1995-06-30 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2225757A1 true CA2225757A1 (en) | 1997-01-23 |
Family
ID=15827772
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2225757 Abandoned CA2225757A1 (en) | 1995-06-30 | 1996-06-25 | Composition and process for treating the surface of aluminiferous metals |
Country Status (7)
| Country | Link |
|---|---|
| EP (1) | EP0837954A4 (en) |
| JP (1) | JP3623015B2 (en) |
| AU (1) | AU708280B2 (en) |
| BR (1) | BR9609331A (en) |
| CA (1) | CA2225757A1 (en) |
| NZ (1) | NZ312858A (en) |
| WO (1) | WO1997002369A1 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| AU744557B2 (en) * | 1997-05-22 | 2002-02-28 | Henkel Corporation | Water-based liquid treatment for aluminum and its alloys |
| US6200693B1 (en) | 1997-05-22 | 2001-03-13 | Henkel Corporation | Water-based liquid treatment for aluminum and its alloys |
| AU757539B2 (en) | 1997-08-21 | 2003-02-27 | Henkel Kommanditgesellschaft Auf Aktien | Process for coating and/or touching up coatings on metal surfaces |
| US6074464A (en) * | 1998-02-03 | 2000-06-13 | Sermatech International, Inc. | Phosphate bonded aluminum coatings |
| WO1999060186A1 (en) * | 1998-05-20 | 1999-11-25 | Henkel Corporation | Composition and process for treating surfaces of light metals and their alloys |
| US6485580B1 (en) | 1998-05-20 | 2002-11-26 | Henkel Corporation | Composition and process for treating surfaces or light metals and their alloys |
| US6679952B2 (en) * | 1999-02-12 | 2004-01-20 | Topy Industries, Limited | Method of coating aluminum and aluminum alloy substrates and coated articles |
| JP4408474B2 (en) * | 1999-01-25 | 2010-02-03 | トピー工業株式会社 | Aluminum alloy substrate coating method and wheel |
| DE19933189A1 (en) * | 1999-07-15 | 2001-01-18 | Henkel Kgaa | Process for the protection against corrosion or aftertreatment of metal surfaces |
| EP1205579B1 (en) * | 2000-11-07 | 2007-04-11 | Nisshin Steel Co., Ltd. | A chemically processed steel sheet excellent in corrosion resistance |
| US7147934B2 (en) | 2000-11-07 | 2006-12-12 | Nisshin Steel Co., Ltd. | Chemically processed steel sheet excellent in corrosion resistance |
| JP4562897B2 (en) * | 2000-11-20 | 2010-10-13 | 三菱アルミニウム株式会社 | Fin material for heat exchanger having non-chromate reaction type underlayer and heat exchanger provided with the same |
| US7077895B2 (en) | 2001-10-30 | 2006-07-18 | Kansai Paint Co., Ltd. | Coating compound for forming titanium oxide film, method for forming titanium oxide film and metal susbstrate coated with titanium oxide film |
| US6887320B2 (en) * | 2002-02-11 | 2005-05-03 | United Technologies Corporation | Corrosion resistant, chromate-free conversion coating for magnesium alloys |
| US6692583B2 (en) * | 2002-02-14 | 2004-02-17 | Jon Bengston | Magnesium conversion coating composition and method of using same |
| US7402214B2 (en) | 2002-04-29 | 2008-07-22 | Ppg Industries Ohio, Inc. | Conversion coatings including alkaline earth metal fluoride complexes |
| US6749694B2 (en) | 2002-04-29 | 2004-06-15 | Ppg Industries Ohio, Inc. | Conversion coatings including alkaline earth metal fluoride complexes |
| DE10358590A1 (en) | 2003-12-12 | 2005-07-07 | Newfrey Llc, Newark | Process for the pretreatment of surfaces of welded parts of aluminum or its alloys and corresponding welded parts |
| JP5215043B2 (en) * | 2008-06-02 | 2013-06-19 | 日本パーカライジング株式会社 | Metal surface treatment liquid and surface treatment method |
| JP2012017524A (en) * | 2010-06-09 | 2012-01-26 | Nippon Paint Co Ltd | Inorganic chromium-free metal surface treatment agent |
| JP6553936B2 (en) * | 2015-04-28 | 2019-07-31 | 株式会社神戸製鋼所 | Method for producing aluminum alloy sheet for packaging container |
| CN105862020A (en) * | 2016-05-31 | 2016-08-17 | 无锡伊佩克科技有限公司 | Steel surface fluoroferrite conversion plating solution and preparation method thereof |
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|---|---|---|---|---|
| CH273704A (en) * | 1940-09-07 | 1951-02-28 | Parker Ste Continentale | Process for coating aluminum. |
| JPS5173938A (en) * | 1974-12-25 | 1976-06-26 | Nippon Packaging Kk | Aruminiumuoyobi sonogokinnohyomenshoriho |
| JPS5424232A (en) * | 1977-07-26 | 1979-02-23 | Nippon Packaging Kk | Surface treating method of aluminum |
| FR2417537A1 (en) * | 1978-02-21 | 1979-09-14 | Parker Ste Continentale | COMPOSITION BASED ON HAFNIUM TO INHIBIT CORROSION OF METALS |
| DE2905535A1 (en) * | 1979-02-14 | 1980-09-04 | Metallgesellschaft Ag | METHOD FOR SURFACE TREATMENT OF METALS |
| AU4751885A (en) * | 1984-10-09 | 1986-04-17 | Parker Chemical Company | Treating extruded aluminium metal surfaces |
| JPH0364484A (en) * | 1989-08-01 | 1991-03-19 | Nippon Paint Co Ltd | Surface treating agent and treating bath for aluminum or aluminum alloy |
| GB2259920A (en) * | 1991-09-10 | 1993-03-31 | Gibson Chem Ltd | Surface conversion coating solution based on molybdenum and phosphate compounds |
| US5143562A (en) * | 1991-11-01 | 1992-09-01 | Henkel Corporation | Broadly applicable phosphate conversion coating composition and process |
| JPH0748677A (en) * | 1993-07-05 | 1995-02-21 | Nippon Parkerizing Co Ltd | Aluminum di can and common surface treatment solution and process for tin di can |
| US5427632A (en) * | 1993-07-30 | 1995-06-27 | Henkel Corporation | Composition and process for treating metals |
| US5449415A (en) * | 1993-07-30 | 1995-09-12 | Henkel Corporation | Composition and process for treating metals |
| DE4401566A1 (en) * | 1994-01-20 | 1995-07-27 | Henkel Kgaa | Process for the common pretreatment of steel, galvanized steel, magnesium and aluminum before joining with rubber |
| JP3315529B2 (en) * | 1994-06-03 | 2002-08-19 | 日本パーカライジング株式会社 | Composition for surface treatment of aluminum-containing metal material and surface treatment method |
-
1995
- 1995-06-30 JP JP16624395A patent/JP3623015B2/en not_active Expired - Fee Related
-
1996
- 1996-06-25 BR BR9609331A patent/BR9609331A/en not_active Application Discontinuation
- 1996-06-25 AU AU64781/96A patent/AU708280B2/en not_active Ceased
- 1996-06-25 EP EP96924286A patent/EP0837954A4/en not_active Withdrawn
- 1996-06-25 CA CA 2225757 patent/CA2225757A1/en not_active Abandoned
- 1996-06-25 WO PCT/US1996/010683 patent/WO1997002369A1/en not_active Application Discontinuation
- 1996-06-25 NZ NZ312858A patent/NZ312858A/en unknown
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| Publication number | Publication date |
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| EP0837954A1 (en) | 1998-04-29 |
| MX9710210A (en) | 1998-03-29 |
| JPH0920984A (en) | 1997-01-21 |
| JP3623015B2 (en) | 2005-02-23 |
| BR9609331A (en) | 1999-05-25 |
| NZ312858A (en) | 1999-11-29 |
| EP0837954A4 (en) | 1998-10-28 |
| AU6478196A (en) | 1997-02-05 |
| AU708280B2 (en) | 1999-07-29 |
| WO1997002369A1 (en) | 1997-01-23 |
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