BACKGROUND OF THE INVENTION Field of the Invention

The entire content of the speci ication of U. S. Pat¬ ent 4,859,351 is hereby incorporated herein by reference. This patent is generally referred hereinafter as "the '351 patent" for brevity. All parts of the specification of U. S. application Serial No. 395,620 filed August 18, 1989 that are not duplicated in U. S. Patent 4,859,351 are also hereby incorporated herein by reference. In addition to the general field given in the '351 patent, one embodiment of this invention is particularly directed to compositions, and processes for using them, that produce a treated formed metal surface that is substantially or entirely free from "water breaks" when wet, or in other words, a surface over which any water present on the surface spreads spontane¬ ously. Another embodiment of this invention is particular¬ ly directed toward aqueous compositions suitable for con¬ tacting formed metal surfaces to deposit thereon after dry¬ ing a mobility enhancing lubricant film, said compositions being protected against deterioration from the action of microorganisms during storage and/or against foaming during use. Statement of Related Art

In addition to the art already noted in the '351 pat- ent, U. S. Patent 4,148,670 of Apr. 10, 1979 to Kelly teaches a conversion coating solution for aluminum contain¬ ing compounds of zirconium and/or titanium, fluoride, and phosphate, and optionally also polyhydroxy compounds, in dissolved form. The phosphate taught is conventional inor- ganic phosphate, and no mobility enhancing benefit obtained by the treatment is taught.

U. S. Patent 3,964,936 of June 22, 1976 to Das teaches a conversion coating solution for aluminum which produces a surface that maintains its shiny appearance and resists discoloration even when treated with boiling water. The coating solution contains compounds of zirconium and fluo-

rine and may also contain boric acid. No use of a phos¬ phorus containing component is taught, nor is any mobility enhancement from the treatment. DESCRIPTION OF THE INVENTION In this description, except in the claims and the op¬ erating examples or where explicitly otherwise indicated, all numbers describing amounts of ingredients or reaction conditions are to be understood as modified by the word "about" in defining the broadest scope of the invention. Operation within the exact numerical limits specified is generally preferred. Also, except where otherwise stated, whenever more than one material is stated to be suitable for a particular component of a composition, it is to be understood that mixtures including any two or more of the listed materials are also equally suitable.

It has now been found that a formed aluminum surface, which has been conventionally thoroughly cleaned and de- greased by sufficient contact with a water based acid or alkaline cleaner, can be effectively and advantageously surface conditioned so as to impart increased mobility, i.e., a lower coefficient of static surface friction, to the surface when subsequently dried, without harming the reflectivity or printability of, or the adherence of lac¬ quer to, the treated surface, by contacting the surface with a composition comprising, or preferably consisting essentially of, water and the following components: (A) a component of water soluble materials selected from the group conforming to general chemical formula I:

R ₅ 4*-(0-CH ₂ - (I),

wherein each of R ¹ , R ³ , and R ⁶ is independently selected from hydrogen and alkyl groups containing 1 -

4 carbon atoms, preferably from hydrogen and methyl, most preferably hydrogen; each of x, y, and z is an integer and is independently selected within the range from 0 - 25; and each of R ² , R ⁴ , and R ⁵ is independent- ly selected from hydrogen, monovalent cations, mono- valent fractions of polyvalent cations, alkyl groups containing 1 - 20 carbon atoms, and aryl and arylalkyl groups containing 1 - 20 carbon atoms; except that at least one of R ² , R , and R ⁵ (i) is not hydrogen and (ii) has at least one alkoxyl group bonded between it and the phosphorous atom in the formula; (B) a component selected from the group of water soluble salts containing ions that comprise atoms selected from the group consisting of Fe, Zr, Sn, Al, and Ce; (C) a metal etching component, preferably selected from the group consisting of nitric acid, sulfuric acid, phosphoric acid, hydrofluoric acid, hydrochloric acid, hydrobromic acid, hydroiodic acid, acid salts of sul¬ furic and phosphoric acids, salts of nitric, sulfuric, phosphoric, hydrofluoric, hydrochloric, hydrobromic, and hydroiodic acids with bases having an ionization product constant less than that of the acid with which they form the salt, and mixtures of any of these; and, optionally, (D) a component selected from molecules conforming to gen¬ eral formula II: R ¹

I

R ⁷ -0-(-CH-CH ₂ -0) _s -X (II), wherein R ⁷ is a linear, cyclic, or branched saturated monovalent aliphatic hydrocarbon moiety containing from 1 to 25, preferably from 4 - 20, carbon atoms; X is selected from the group consisting of hydrogen, halogen, phenyl, and R ¹ ; s is an integer from 1 to 50, preferably from 1 to 20; and R ¹ has the same meaning as for formula I; (E) a component selected from molecules conforming to gen¬ eral formula III:

R ¹

R ⁸ -(C ₆ H ₄ )-O-(-CH-CH ₂ -0),-H (III), wherein R ⁸ is a linear, cyclic, or branched saturated monovalent aliphatic hydrocarbon moiety containing from 4 to 25, preferably from 8 - 12, most preferably 9, carbon atoms; (C ₆ H ₄ ) is an ortho, meta, or para phenylene nucleus; and R ¹ and s have the same meaning as for formula II; (F) a component selected from chelating agents for the metal containing ions of component (B) , preferably selected from the group consisting of molecules, in¬ cluding polymer molecules, each containing at least two moieties selected from group consisting of amino, substituted amino, carboxyl, phosphonate, sulfonate, and carbonyl moieties; (G) a component selected from molecules conforming to general formula IV:

0 R ¹

R ¹⁰ -C-O-(-CH-CH ₂ -0) _χ -H (IV) , wherein R ¹⁰ is a linear or branched, saturated or unsaturated monovalent aliphatic hydrocarbon moiety containing from 1 to 25, preferably from 4 - 20, car- bon atoms; and R ¹ and x have the same meaning as in formula I.

It should be noted that not all of the specified com¬ ponents must be separate materials. Fluorozirconic acid (i.e. H ₂ ZrF ₆ ) , for example, can serve as both component (B) and component (C) .

It is preferable for component (A) to be selected from molecules conforming to formula I when each of x and z is zero and each of R ² and R ⁵ is hydrogen or a cation or cation fraction, and such materials can serve as all of components (A) , (B) , and (C) , for example if R ² is hydrogen and R ⁵ is

(l/3)Fe ⁺³ .

It is preferred that the amount of component (A) in a solution used for treating according to this embodiment of this invention be such as to provide a concentration of

from 0.00001 to 0.0032 gram atoms of phosphorus per liter, or more preferably from 0.0005 to 0.0015 gram atoms of phosphorus per liter. It is also independently preferred that the amount of component (B) in a solution used for treating according to this embodiment of this invention be such as to provide a concentration of from 0.00001 to 0.01 gram atoms per liter, or more preferably from 0.0001 to 0.003 gram atoms per liter, of the total of all metal atoms recited in component (B) . It is also independently preferred that component (A) be selected from molecules according to formula I when (i) x is either zero or not less than 0.5 the number of carbon atoms in R ² ; (ii) y is either zero or not less than 0.5 the number of carbon atoms in R ⁴ ; and (iii) z is either zero or not less than 0.5 the number of carbon atoms in R ⁵ .

Irrespective of its detailed composition, the composi¬ tion with which a formed aluminum surface is contacted dur¬ ing a process according to this embodiment of this inven¬ tion preferably contains from 0.001 to 10 % by weight ("w%") , more preferably 0.005 - 0.05 w%, of the total of components (A) , (B) , and (C) , as described above, with op¬ tional components and water making up the balance. The water used need not necessarily be deionized or otherwise specially purified; ordinary tap water usually gives satis- factory results. The pH of the composition during contact with a formed aluminum surface preferably is in the range of 1 - 8, more preferably in the range of 2 - 5. The pH may be adjusted as needed, preferably with nitric and/or sulfuric acid, during use, in order to maintain the pH within the desired range. The temperature of the composi¬ tion during contact with the formed aluminum surface is preferably from 10 - 85° C, more preferably from 21 - 54° C. Contact may be by spraying, immersion, or any other convenient method or mixture of methods. Preferably the time of contact is from 5 - 60, more preferably from 20 - 30, seconds. It is also generally preferable to rinse the treated surface first with tap water and then again with

deionized water after treatment according to the invention and before further processing, such as drying, printing, lacquering, or the like.

Independently of all other preferences, it is prefer- able if a composition according to this embodiment of this invention contains optional components (D) and (E) as de¬ fined above in amounts sufficient to prevent or at least substantially reduce any tendency toward gross, visually detectable phase separation that the composition otherwise may have. It has been found that in compositions contain¬ ing only components (A) through (C) and optionally compon¬ ents (F) and (G) as defined above, a phase enriched in met¬ al content tends to separate from the remainder of the com¬ position after the composition has been in use for some time after make-up. Preferably the ratio by weight of component (D) to component (E) is in the range from 3:1 to 1:3, or more preferably in the range from 1.7:1 to 1:1.4. Independently, it is preferable if the ratio by weight of the combined components (D) and (E) to component (A) is in the range from 3.3:1 to 1:2, or more preferably in the range from 1.8:1 to 1:1.5.

In addition to a process of treating and the composi¬ tion used directly for treating, another embodiment of the invention is a concentrate from which the composition to be used for treating can be made by dilution with water. Such a concentrate preferably contains the components (A) , (B) , (C) , and optionally (D) , (E) , (F) , and/or (G) as noted above in an amount of from 30 - 200 times the w% level not¬ ed above for the composition for direct use in treating metal surfaces.

The compositions and methods of these embodiments of this invention have several advantages over those described in the '351 patent: after treatment according to this invention, a surface can be rinsed many more times with tap or deionized water without losing improved surface mobility and other advantages than can a surface treated according

to the examples of the *351 patent; if there is prolonged contact between the treated sur¬ face and a cleaning composition or one of the rinses after cleaning but prior to treatment with a composi- tion according to this invention (as a result of un¬ planned stoppages of a high speed production line, for example) , light-to-deep brown spots, believed to be hydrated aluminum oxide, sometimes form on the treated surface; any such spots are removed by treatment ac- cording to this invention, whereas they usually per¬ sist after using a process as taught in the examples of the •351 patent; a process according to this invention may more readily be operated at a pH sufficiently low to inhibit bac- terial growth than one according to the examples of the '351 patent; almost any readily available industrial or tap water supply may be used for makeup or dilution of a compos¬ ition according to this invention, while that taught in the '351 patent generally needs deionized water for best results; - the surfaces produced by a process according to the present invention are very readily wet by water and thus remain free of "water breaks", which are con- sidered undesirable by most aluminum can processors; cans processed according to the examples of the '351 patent are much more likely to exhibit water breaks. Another embodiment of the present invention comprises compositions and their use as described explicitly above, and compositions and their use as described in the above referenced application Serial No. 395,620 and U. S. Patent 4,859,351), which are protected against deterioration from microorganisms during storage and/or use and/or from foam¬ ing during preparation and/or use. Any antimicrobial or biocidal agent, except those hav¬ ing some detrimental effect on the mobility enhancing prop¬ erties or the stability of the composition, may advantage-

ously be added to the compositions as previously taught herein in an amount sufficient to effectively inhibit the growth of microorganisms. Hydrogen peroxide is generally most preferred for this purpose. In aqueous concentrated compositions, suitable for dilution with about 99 times their own weight of water to make a composition ready for direct application to metal to enhance mobility after dry¬ ing, as already described, concentrations of hydrogen per¬ oxide in the range from 0. 375 to 3.75 w% are preferred, with concentrations in the range from 1.4 - 2.2 w% most preferred. In more concentrated compositions the preferred biocide concentrations would be determined by the expected degree of dilution of the concentrate. In general, how¬ ever, because of the relatively low stability of concen- trated hydrogen peroxide, it is preferred that this com¬ ponent, if used, be added only to a sufficiently dilute concentrate that the concentration of hydrogen peroxide does not exceed about 3 w%. at the time of making up the composition. Any antifoam agent, except those which have some det¬ rimental effect on the mobility enhancing properties al¬ ready described or the stability of the compositions, may advantageously be added to the compositions as previously taught herein, in an amount effective to decrease the amount of foaming observed during preparation and/or use of the compositions. The preferred antifoam agent is a combi¬ nation of wax, low volatility liquid paraffin hydrocarbons, and high molecular weight fatty acid derivatives. General¬ ly, silicone antifoam agents are not desirable for use with this invention because they tend to cause formation of wat¬ er breaks. An amount of antifoam agent corresponding to 0.05 to 2 w% is generally preferred, with 0.5 - 1 w% gen¬ erally more preferred.

All the advantages of increased mobility, low surface coefficient of friction, high quality printability, and good adhesion of lacquers and the like as taught in the '351 patent are retained for treatments according to this

invention.

The practice of this invention may be further appreci¬ ated by consideration of the following non-limiting examp¬ les. EXAMPLES

General Conditions for Examples 1 - 7 and Comparison

In all these examples, the surfaces treated were those of conventional aluminum beverage cans already in their final shape and size. The cans were subjected to an acid prewash in an aqueous solution sulfuric acid having a pH of 2 for 30 seconds ("sec") at 54° C, then to washing with a conventional alkaline, surfactant containing cleaner at pH 12.3 for 60 sec at 54° C, and then to a 30 sec tap water rinse before being treated with a composition according to this invention as set forth in the specific examples below. (The compositions given in the specific examples are for concentrates according to this invention; for treatment, a solution of the w% of the concentrate specified in Table 1, in tap water, was used.) After this treatment, the cans were rinsed first in tap water for 30 sec, then in deion¬ ized water for 90 sec, and dried at 210° C. The coeffi¬ cient of static surface friction on the cans after drying was measured as described in the '351 patent.

Example 1 The concentrate for this example had the following composition:

Ingredient Parts by Weight in Composition

Stannic chloride solution, _ ₀₀

25 % by weight in water ETHFAC™ 136 400

ETHOX™ MI-14 100

Ammonium bifluoride solution, ₁₃₅

25 % by weight in water

DEQUEST™ 2010 25 Water 9040

Example 2

The concentrate for this example had the following composition:

Ingredient Parts by Weight in Composition

Ferric ammonium citrate ₃₀₀ solution, 25 % by weight in water

ETHFAC™ 136 400

ETHOX™ MI-14 100

Ammonium bifluoride solution, ₁₃₅ 25 % by weight in water DEQUEST™ 2010 25

Water 9040

Example 3

The concentrate for this example had the following composition: Ingredient Parts by Weight in Composition

Cerium ammonium sulfate 4

ETHFAC™ 136 30

Ammonium bifluoride solution, ₁₆ 25 % by weight in water DEQUEST™ 2010 2

Sulfuric acid 1

TRITON™ N 101 5

Water 942

Example 4 The concentrate for this example had the following composition:

Ingredient Parts by Weight in Composition

Aluminum chloride 10

ETHFAC™ 136 50 Ammonium bifluoride solution, ,, 25 % by weight in water

TRITON™ N101 6

Citric acid 6

Ethoxylated alcohol surfactant 11 Water 906

Example 5

The concentrate for this example had the following

composition:

Ingredient Parts by Weight in Composition

Fluorozirconic acid 15

Mono(hexyltriethoxy) phosphate 70 Poly(oxyethylene) isostearate with an average of 14 oxyethylene units per 20 isostearate unit

Ammonium bifluoride solution, _ιg

25 % by weight in water Aminoacetic acid 20

Water 856

Example 6

The concentrate for this example had the following composition: Ingredient Parts by Weight in Composition

Fluorozirconic acid 15

Mono(hexyltriethoxy) phosphate 30

ETHOX™ MI-14 20

Ammonium bifluoride solution, ₁₅ 25 % by weight in water

Butane-2-phosphonic acid tricarboxylate 10

Water 910

Example 7

The concentrate for this example had the following composition:

Ingredient Parts by Weight in Composition

Fluorozirconic acid 10

Polyoxyethylene isostearate containing an average of 14 moles of -C ₂ H ₄ 0- groups 10 per mole of isostearate

TRITON™ H-66 80

DEQUEST™ 2010 2.5

Ammonium bifluoride solution, .

25 % by weight in water Water 893.5

In the compositions given above, DEQUEST 2010 is a trade name for a material that is reported to be predom¬ inantly 1-hydroxyethylidene-l-diphosphonic acid, and TRITON

NlOl is a trade name for a surfactant material that is reported to be predominantly nonylphenoxypoly(ethoxy)etha- nol, with an average of 9 - 10 ethoxy groups per molecule. Table 1 shows the specific amounts of the concentrates used, treatment conditions, and the coefficients of static surface friction achieved on the cans by sorption of a lubricant and surface conditioning layer for these ex¬ amples.

Table 1

IMPROVEMENT IN SURFACE FRICTION FROM TREATMENT ACCORDING

TO

THIS INVENTION

Experiment % by Weight of Treatment Conditions Coefficient Number Concentrate in Temperature, Time, of Static Treatment Degrees C Seconds Surface Solution Friction

1 1.0 35 20 1.27

2 1.0 35 20 1.47

3 1.0 35 20 1.31

4 1.0 35 20 0.77

5 1.0 35 20 0.77

6 1.0 35 20 1.20

7 1.0 35 20 1.01

No treatment 1.67

Example 8

This is an example of a composition that contains a preferred antifoam agent and a preferred biocide, but oth- erwise is according to the teachings of the '351 patent.

A first concentrate is prepared by mixing 880 parts by weight ("PBW") of ETHOX™ MI-14, 60 PBW of COLLOID 999™ (a high molecular weight fatty acid derivative, available com¬ mercially from Colloids, Inc., 394 Frelinghuysen Ave. , New- ark, New Jersey 07114, U.S.A.), and 60 PBW of GP-295™ De- foamer (a suspension of about 10 % solid wax in white min¬ eral oil, available commercially from Genese Polymers Corp., Flint, Michigan 48507, U.S.A.). The ETHOX™ MI-14 is

first melted in a mixing tank at 27 - 32 ° C. The other two materials are then added in the order noted and mixed for form a cloudy but visually homogeneous liquid with no lumps. A second concentrate suitable for storage for at least several months is then made by mixing 47 PBW of the first concentrate described above with 917 PBW of water, prefer¬ ably deionized water, and with 40 PBW of 37.5 % aqueous hydrogen peroxide. This second concentrate may then be diluted when desired to make a composition suitable for directly treating aluminum surfaces as generally described in the '351 patent.

Examples 9 and 10

These examples illustrate preferred stabilized compo- sitions including metal containing salts and ethoxylated phosphates. The compositions set forth in Table 2 below are concentrates, suitable for use in treating metal con¬ tainers after being diluted with, e.g., 50 - 200 times their own weight of tap water.

Table 2: COMPOSITIONS FOR EXAMPL LEESS 9 AND 10

Ingredient PBW in Example >. No. :

9 10

Deionized water 920 856 ETHOX™ 2684 14 60

TRITON™ DF-16 12 -

TRYCOL™ LF-1 4 30

IGEPAL™ CO-880 2Q}

DEQUEST™ 2010 3 - Ammonium bifluoride (NH ₄ F-HF) 11 4

Fluorozirconic acid (H ₂ ZrF ₆ ) 25 20

Sources and characterizations of ingredients in Table 2 not previously identified are as follows: ETHOX™ 2684, commercially available from Ethox Chemicals, Inc., Green¬ ville, South Carolina 20606, USA, corresponds to formula I with x and z both zero, R ² , R ³ , and R ⁵ all representing

hydrogen, R ⁴ representing a mixture of C ₈ . ₁₀ linear alkyl groups, and y averaging about 15. TRITON™ DF-16, commer¬ cially available from Rohm & Haas, Philadelphia, Pennsyl¬ vania 19105, USA, is reported to be a modified polyethoxyl- ated straight chain alcohol. TRYCOL™ LF-1, commercially available from the Emery Chemical Division of Henkel Cor¬ poration, Cincinnati, Ohio 45249, USA, is reported to be an alkyl polyether. IGEPAL™ CO-880, commercially available from GAF Corp, Wayne, New Jersey 07470, USA, is reported to be an ethoxylated nonyl phenol.

What is claimed is: