AU707266B2 - Aqueous lubricant and surface conditioner for formed metal surfaces - Google Patents

Description

r IUVU1 1 21V5/9; Regulation 3.2(2)

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD

PATENT

*5e*

S

*5*S S

S

S S Application Number: Lodged: Invention Title: AQUEOUS LUBRICANT AND SURFACE CONDITIONER FOR FORMED METAL SURFACES

SS

The following statement is a full description of this invention, including the best method of performing it known to us- AQUEOUS LUBRICANT AND SURFACE CONDITIONER FOR FORMED METAL SURFACES BACKGROUND OF THE INVENTION Field of the Invention This invention relates to processes and compositions which accomplish at least one, and most preferably all, of the following related objectives when applied to formed metal surfaces, more particularly to the surfaces of cleaned aluminium and/or tin plated cans: reducing the coefficient of static friction of the treated surfaces after drying of such surfaces, without adversely affecting the adhesion of paints or lacquers applied thereto; (ii) promoting the drainage of water from treated surfaces, without causing "water-breaks", promoting drainage that results in a thin, continuous film of water on the cans, instead of distinct water droplets separated by the relatively dry areas called "waterbreaks" between the water droplets; and (iii) lowering the dryoff oven *temperature required for drying said surfaces after they have been rinsed with water.

Discussion of Related Art The following discussion and the description of the invention will be set forth primarily for aluminium cans, as these represent the largest volume area of application of the invention. However, it is to be understood that, with the obviously necessary modifications, both the discussion and the description of the invention apply also to tin plated steel cans and to other types of formed metal surfaces for which any of the above stated intended purposes of the invention is practically interesting.

Aluminium cans are commonly used as containers for a wide variety of products. After their manufacture, the aluminium cans are typically washed with acidic cleaners to remove aluminium fines and other contaminants therefrom.

Recently, environmental considerations and the possibility that residues remaining on the cans following acidic cleaning could influence the flavour of beverages packaged in the cans has led to an interest in alkaline cleaning to remove such fines and contaminants. However, the treatment of aluminium cans with either alkaline or acidic cleaners generally results in differential rates of metal surface etch on the outside versus on the inside of the cans. For example, optimum conditions required to attain an aluminium fine-free surface on the inside of the cans usually leads to can mobility problems on conveyors because of the increased roughness on the outside can surface.

Aluminium cans that lack a low coefficient of static friction (hereinafter often abbreviated as "COF") on the outside surface usually do not move past each other and through the trackwork of a can plant smoothly. Clearing the jams resulting from failures of smooth flow is inconvenient to the persons operating the plant and costly because of lost production. The COF of the internal surface is also important when the cans are processed through most aconventional can decorators. The operation of these machines requires cans to S slide onto a rotating mandrel which is then used to transfer the can past rotating cylinders which transfer decorative inks to the exterior surface of the cans. A can that does not slide easily on or off the mandrel can not be decorated :a.properly and results in a production fault called a "printer trip". In addition to the a."misloaded can that directly causes such a printer trip, three to four cans before and after the misloaded one are generally lost as a consequence of the .,.mechanics of the printer and conveyor systems. Jams and printer trips have become increasingly troublesome problems as line speed have increased during recent years to levels of about 1200 to 1500 cans per minute that are now common. Thus, a need has arisen in the can manufacturing industry, particularly with aluminium cans, to modify the COF on the outside and inside surfaces of the cans to improve their mobility.

An important consideration in modifying the surface properties of cans is the concern that such modification may interfere with or adversely affect the ability of the can to be printed when passed to a printing or labelling station. For example, after cleaning the cans, labels may be printed on their outside surface, and lacquers may be sprayed on their inside surface. In such a case, the adhesion of the paints and lacquers is of major concern. It is therefore an object of this invention to improve mobility without adversely affecting adhesion of paints, decorating inks, lacquers, or the like.

In addition, the current trend in the can manufacturing industry is directed toward using thinner gauges of aluminium metal stock. The down-gauging of aluminium can metal stock has caused a production problem in that, after washing, the cans require a lower drying oven temperature in order to pass the column strength pressure quality control test. However, lowering the drying oven temperature resulted in the cans not being dry enough when they reached the printing station, and caused label ink smears and a higher rate of can rejects.

One means of lowering the drying oven temperature would be to reduce the amount of water remaining on the surface of the cans after water rinsing.

Thus, it is advantageous to promote the drainage of rinse water from the treated can surfaces. However, in doing so, it is generally important to prevent the formation of surfaces with water-breaks as noted above. Such water-breaks give rise to at least a perception, and increase the possibility in reality, of nonuniformity in practically important properties among various areas of the S. surfaces treated.

SS*Thus, it is desirable to provide a means of improving the mobility of aluminium cans through single filers and printers to increase production, reduce 0 **,line jamming, minimize down time, reduce can spoilage, improve or at least not adversely affect ink laydown, and enable lowering the drying oven temperature of washed cans.

In the most widely used current commercial practice, at least for large scale operations, aluminium cans are typically subjected to a succession of six cleaning and rinsing operations as described in Table 1 below. (Contact with ambient temperature tap water before any of the stages in Table 1 is sometimes used also; when used, this stage is often called a "vestibule" to the numbered stages.) Table 1 STAGE ACTION ON SURFACE DURING STAGE

NUMBER

1 Aqueous Acid Precleaning 2 Aqueous Acid and Surfactant Cleaning 3 Tap Water Rinse 4 Mild Acid Postcleaning, Conversion Coating, or Tap Water Rinse Tap Water Rinse 6 Deionized Water Rinse It is currently possible to produce a can which is satisfactorily mobile and to which subsequently applied inks and/or lacquers have adequate adhesion by 15 using suitable surfactants either in Stage 4 or Stage 6 as noted above.

Preferred treatments for use in Stage 6 are described in U. S. Patents 4,944,889 and 4,859,351, and some of them are commercially available from the Parker+Amchem Division of Henkel Corporation (hereinafter often abbreviated as under the name "Mobility EnhancerTM 40" (herein often abbreviated However, many manufacturers have been found to be reluctant to use chemicals such as "ME-40TM" in Stage 6. In some cases, this reluctance is due to the presence of a carbon filter for the DI water (normal Stage 6) system, a filter that can become inadequately effective as a result of adsorption of lubricant and surface conditioner forming additives such as those in "ME-40TM"; in other cases, it is due to a reluctance to make the engineering changes necessary to run For those manufacturers that prefer not to add any lubricant and surface conditioner material to the final stage of rinsing but still wish to achieve the advantages that can be obtained by such additions, alternative treatments for use in Stage 4 as described above have been developed and are described in U. S. Patents 5,030,323 and 5,064,500. Some of these materials are commercially available from P+A under the name FIXODINETM 500.

However, the reduction in coefficient of friction provided by prior art treatments in either Stage 4 or Stage 6 can be substantially reduced, often to an unacceptable level, if the treated cans are subjected to extraordinary heating after completion of the six process stages described above. Such extraordinary heating of the cans in the drying oven occurs whenever a high speed production line is stalled for even a few minutes, an event that is by no means rare in practice. In practical terms, the higher COF measurements correlate with the loss of mobility, thereby defeating the purpose of introducing mobility enhancing surfactants into can washing formulations. Accordingly, it is an object of this invention to provide means of improving the mobility of aluminium cans and/or one of the other objects stated above that are superior to means taught in the prior art, particularly with respect to stability of the beneficial effects to heating well beyond the minimum extent necessary for drying the treated surfaces.

Also, some beverages packaged in aluminium cans are pasteurised, and 4 4unless the temperature and the composition(s) of the aqueous solution(s) with *which cans are contacted during pasteurisation are very carefully controlled, staining of the dome of the can often occurs during pasteurisation. It is a further *4*S*4 object of this invention to provide compositions and methods suitable for use in reducing coefficient of friction that will also resist such dome staining during pasteurisation.

A still further major object of the invention is to provide adequate mobility enhancement without practically significant deterioration of subsequent adhesion to the treated surface by printing ink or lacquer, as little deterioration as possible of this mobility enhancement under extended heating at temperatures typical for drying ovens on high speed can lines, and stability to storage in hot weather of a concentrate or pair of concentrates suitable for diluting with water to make the working solution for direct treatment of cans DESCRIPTION OF THE INVENTION Other than in the operating examples, or where otherwise indicated, all numbers expressing quantities of ingredients or reaction conditions used herein are to be understood as modified in all instances by the term "about" in 6 describing the broadest scope of the invention. Practice within the numerical limits given, however, is generally preferred.

Also, unless there is an explicit statement to the contrary, the description below of groups of chemical materials as suitable or preferred for a particular ingredient according to the invention implies that mixtures of two or more of the individual group members are equally as suitable or preferred as the individual members of the group used alone. Furthermore, the specification of chemical materials in ionic form should be understood as implying the presence of some centurions as necessary for electrical neutrality of the total composition. In general, such counterions should first be selected to the extent possible from the ionic materials specified as part of the invention; any remaining counterions .needed may generally be selected freely, except for avoiding any counterions that are detrimental to the objects of the invention.

Summary of the Invention In accordance with this invention, it has been found that a lubricant and surface conditioner applied to aluminium cans after washing enhances their mobility and, in a preferred embodiment, improves their water film drainage and evaporation characteristics as to enable lowering the temperature of a drying S. oven by from about 250 to about 380 C without having any adverse effect on the label printing process. The lubricant and surface conditioner reduces the coefficient of static friction on the outside surface of the cans, enabling a substantial increase in production line speeds, and in addition, provides a noticeable improvement in the rate of water film drainage and evaporation resulting in savings due to lower energy demands while meeting quality control requirements.

In particular, the present invention provides a process comprising steps of cleaning a formed metal container, preferably an aluminium can or tin-plated steel can, with an aqueous acidic or alkalinecleaning solution, (ii) subsequently contacting at least one exterior surface of the cleaned metal container with an aqueous lubricant and surface conditioner forming composition, (iii) drying the metal container after steps and and (iv) subsequently conveying the cleaned and dried can via automatic conveying equipment to a location where it is lacquered or decorated by printing or both, characterised in that the aqueous lubricant and surface conditioner comprises: a dissolved phosphorus containing surfactant component that is a mixture of molecules conforming to the general formula I: (O-Y-R)x

O=P

O=P (OM)y 5 where M is selected from the group consisting of H, alkali metal cations, monovalent fractions of alkaline earth metal cations, and monovalent fractions of ammonium and substituted ammonium cations, or preferably from the group consisting of H and alkali metal cations; x= 1 or 2 and y 3-x; Y is an alkylene or alkylene ether group, which may be branched or unbranched, with its open 10 valances on carbon atoms and with from 2 to 12, preferably from 2 to 4, most preferably 2, carbon atoms and up to 3, preferably no more than one, more preferably no oxygen atoms; and R is an imidazoline moiety conforming to general formula II:

(II),

R

3 -C R 1

R

2 where each of R1 and R2 is independently selected, except that R1 and R2 may not both be hydrogen, from the group consisting of hydrogen, a moiety derived from propionitrile by removing a hydrogen atom from the -CH 3 group thereof, and moieties of the general formula III:

-CH

2

CH

2 C-Q

II

8 where Q is selected from the group consisting of -OM, -NH2, and -OR4, where M has the same meaning as defined above and R4 represents a C2 12 alkyl, alkylaryl, or alkylcycloaliphatic moiety; preferably, R1 and R2 are selected from the group consisting of hydrogen and moieties of general formula III when Q OM and M H or an alkali metal ion; and R3 is selected from the group consisting of unsubstituted and hydroxy substituted aliphatic and cycloaliphatic and alkylaryl moieties, or preferably from the group consisting of unsubstituted and unbranched aliphatic moieties, having from 2 to 22 carbon atoms; with increasing preference in the order given, at least 50, 64, 76 or 84 mole percent of the total R3 groups in the composition have from 8 to 20, or more preferably from 10 to 14, carbon atoms; a component selected from the group of water soluble salts containing ions that comprise atoms selected from the group consisting of Zr, Ti, Sn, Al, and Fe: a metal etching component, preferably selected from the group consisting of nitric, sulfuric, phosphoric, hydrofluoric, hydrochloric, hydrobromic, and hydroiodic acids; acid salts of sulfuric, phosphoric, and hydrofluoric acids; and 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 "free fluoride ions"; and, optionally, any one or more of the following: a component selected from molecules conforming to general formula IV:

R

(IV),

R

6

CH

2 X wherein R6 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 R5; s is an integer from 1 to 50, preferably from 1 to 20; and R5 is selected from the group consisting of hydrogen and alkyl groups containing 1-4 carbon atoms, preferably from hydrogen and methyl, most preferably hydrogen; a component selected from molecules conforming to general formula V: 0 I I

(V)

R

7 -(C6H 4 O)s-H wherein R7 is a linear, cyclic, or branched saturated monovalent aliphatic hydrocarbon moiety containing from 4 to 25, preferably from 8 to 12, most preferably 9, carbon atoms; (C6H 4 is an ortho-, meta-, or para-phenylene nucleus; and R5 and s have the same meaning as for formula IV; a component selected from molecules conforming to general formula VI: O

R

s 0 II I

(VI)

R

8 C-O(-CH-CH s-H wherein R8 is a linear or branched, saturated or unsaturated monovalent aliphatic hydrocarbon moiety containing from 1 to 25, preferably from 4 S: 10 carbon atoms; and R5 and s have the same meaning as in formula IV; a component selected from chelating agents for the metal containing ions component preferably selected from the group consisting of molecules, including polymer molecules, each containing at least two moieties selected from group consisting of amino, substituted amino, carboxyl, phosphonate, sulfonate, and carbonyl moieties; and an antimicrobial agent.

It should be noted that not all of the specified components must be separate materials. For example, fluozirconic acid

H

2 ZrF 6 can serve as both component and component and ammonium bifluoride or hydrofluoric acid can serve as both components and Also, the same components as specified above for a single package additive may be, and often preferably are, comprised instead in a pair of two distinct additives. For maximum storage stability, a two package additive pair, with most or all of the metal etching component as defined above in a separate package from the other ingredients, is generally preferred.

Components and as defined above are generally used only when their action as an antifoam agent is desired or needed, because of a foaming tendency of compositions containing the four required components Component is generally included only when needed to solubilize the desired concentration of component Component is generally used only if needed to avoid growth of microorganisms in the compositions when they are used.

Various embodiments of the invention include a concentrated additive or pair of additive compositions as described above; a solution of such an additive composition or pair of additive compositions in water, optionally with additional acid or base to adjust the pH value, suitable as the complete composition for contacting the metal surfaces in Stage 4 of a six stage cleaning and rinsing process as described above; and processes including contacting a metal surface, particularly an aluminium surface, with an aqueous composition including the ingredients of the additive composition specified in detail above.

aThe working compositions for Stage 4 as described above, in addition to the components included by virtue of dilution of a concentrated additive or additive package as specified above may also contain aluminate an6ns, including fluoroaluminate anions; and aluminium cations, including complex dragout from Stages 2 and 3 into Stage 4 during practical large scale operations.

Further, the additive may not require the use of any further additive to DI water used in Stage 6 above.

Brief Description Of The Drawings Figures l(a) to 1(d) illustrate the effect of fluoride activity during cleaning of cans before applying a lubricant and surface conditioner according to this invention on the characteristics of the cans after processing.

Description of Preferred Embodiments For necessary components and certain minimum concentrations are strongly preferred in order to obtain optimum surface characteristics on the treated surfaces, and large excesses over these minimum concentrations have not been observed to do any harm in so far as the quality of the treatments is concerned. However, since a certain amount of the treatment compositions will be lost in normal processing, it is economically advantageous to avoid overwhelmingly large concentrations of these components, which would increase the amount wasted. For necessary components and in contrast, very large concentrations can cause surface damage as well as being uneconomical.

Irrespective of its detailed composition with which a formed aluminium surface is contacted during a process according to this embodiment of this invention preferably contains from 0.001 to 10% by weight more preferably 0.005 0.05 w/o, of the total of components and as described above, with optional components and water making up the balance.

The water used need not necessarily be deionized or otherwise specially *l purified; ordinary tap water usually gives satisfactory results. The pH of the composition during contact with a formed aluminium 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 sulphuric acid, during use, in order to maintain the pH within the desired range. The temperature of the composition during contact with the formed aluminium surface is preferably from 10-85°C, more preferably from 21-540C. Contact may be spraying, immersion, or any .~l other convenient method or mixture of methods. Preferably the time of contact is from 5-60, more preferably from 20-30, seconds.

The "Free fluoride ion" activity for purposes of this invention is defined and can conveniently be measured, and monitored during use if desired, by means of fluoride sensitive electrode as described in U.S. Patent 3,431,182 and commercially available from Orion Instruments. "[Free] fluoride ion activity" as this term is used herein was measured relative to a 120E Activity Standard Solution commercially available from the Parker+Amchem Division of Henkel Corporation by a procedure described in detail in P+A Technical Process Bulletin No. 968. The Orion Fluoride Ion Electrode and the reference electrode provided with the Orion instrument are both immersed in the noted Standard Solution and the millivolt meter reading is adjusted to 0 with a Standard Knob on the instrument, after waiting if necessary for any drift in readings. The electrodes are then rinsed with deionized or distilled water, dried, 12 and immersed in the sample to be measured, which should be brought to the same temperature as the noted Standard Solution had when it was used to set the meter reading to 0. The reading of the electrodes immersed in the sample is taken directly from the millivolt (hereinafter often abbreviated meter on the instrument. For a working composition, a composition suitable as such for use in Stage 4 of a processing sequence as defined above, according to this invention, the fluoride ion activity preferably is such as to result in a meter reading, with increasing preference in the order given, within the range from to -130 my, -60 to -120mv, -75 to -105mv, or -85 to Any antimicrobial or biocidal agent, except those having some detrimental effect on the mobility enhancing properties or the stability of the i composition, may advantageously 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 S99 times their own weight of water to make a composition ready for direct S* application to metal to enhance mobility after drying, as already described, concentrations of hydrogen peroxide in the range from 0.375 to 3.75 w/o are preferred, with concentrations in the range from 1.4 to 2.2 w/o most preferred. in more concentrated compositions the preferred biocide concentrations would be determined by the expected degree of dilution of the concentrate. In general, however, because of the relatively low stability of concentrated hydrogen peroxide, it is preferred that this component, if used, be added only to a sufficiently dilute concentrate that the concentration of hydrogen peroxide does not exceed about 3 w/o at the time of making up the composition.

Any antifoam agent, except those which have some detrimental effect on the mobility enhancing properties already described or the stability of the compositions, may advantageously be added when needed 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.

Generally, silicone antifoam agents are not desirable for use with this invention because they tend to cause formation of water breaks. Preferably, the antifoam 13 agents correspond to one of general formulas IV, V and VI as given above, most preferably to formula IV. In a working composition for a Stage 4 bath, the amount of total antifoam agent is preferably from 0.0001 to 0.05 w/o, more preferably from 0.001 to 0.01 w/o, or still more preferably from 0.002 to 0.008 w/o.

The characteristics of and methods of making phosphorus containing surfactants as required for component of a composition according to this invention are described in detail in U.S. Patent 4, 490, 536 of Dec. 25, 1984 to Corti et al. The most preferred constituents for component are those in which R3 in general formula II represents straight chain unsubstituted and saturated o-,9 alkyl groups. Independently, the most preferred constituents for component (A) 9999 are those in which M in general formula I represents an alkali metal cation.

For component the most preferred constituent is fluozirconic acid, i.e.

H

2 ZrF6, and/or fluozirconate salts, and it is preferred that component and/or include bifluoride ions,

HF

2 ions. Also components of type are °;99preferred over those of types and primarily because they lead to working compositions that have less tendency to generate foam.

~It is preferred that the amount of component in a solution used for treating according to this embodiment of this invention be such as to provide a concentration of at least 0.000012, or, with increasing preference in the order 9• given at least 0.000025, at least 0.000051, or at least 0.00019, gram atoms of phosphorus per liter. Independently, primarily for cost reasons as already noted, it is preferred that the amount of component in such a working composition should not exceed the amount necessary to provide 0.005, more preferably 0.001, or still more preferably 0.00031, gram atoms of phosphorus per liter. It is also independently preferred that the amount of component in a solution used for treating according to this embodiment of this invention a concentration of at least from 0.00002, or, with increasing preference in the order given, at least 0.000042, at least 0.000097, or at least 0.00038 gram atoms per liter of the total of all the metal atoms recited in component Independently, it is preferred that the amount of component in such a working composition should not exceed the amount necessary to provide 0.005, more preferably 14 0.002, or still more preferably 0.00059, gram atoms per liter of the total of all the metal atoms recited in component In addition to the values for "free fluoride ion activity" already given, it is independently preferred that the total concentration of fluorine atoms in components of the composition selected from the group consisting of fluoride ions, bifluoride salts, and hydrogen fluoride in a working composition according to this invention should be at least 0.00001, or, with increasing preference in the order given, at least 0.000051, at least 0.00012, at least 0.00029, or at least 0.0011, gram atoms of fluorine per liter.

For concentrates, the concentrations of all ingredients other than water ."are preferably 5 to 100, more preferably 40 to 400, still more preferably 105 to 215, or most preferably 150 to 170, times higher than the values given above.

In a process according to this invention, the amount of material added on to the treated surface during exposure to a composition according to the invention preferably is sufficient to cause the COF of the surface as finally °;.*.processed to be not greater than 1.5, more preferably not greater than 1.2, still 9.*more preferably not greater than 1.0, and most preferably not greater than 0.8.

Also, independently, the COF of the surface as treated according to this *99invention preferably is not greater than 90% of the value that the surface would have had if treated in the same way, except for substituting contact with deionized water for contact with a composition according to this invention.

The invention may be further appreciated by consideration of the following examples and comparison examples, which are intended to be merely descriptive, illustrative, and not limiting as to the scope of the invention, except to the extent that any limitations given in the examples may be repeated in the appended claims.

General Conditions for Examples and Comparison Examples All the process examples and comparison examples described below in this group used aluminium cans as substrates and a laboratory prototype a a.

a a a. a a. simulation of a commercial six stage processor. Each run was made with 14 cans. The process sequence used is described in Table 2 TABLE 2 Stage Time in seconds for: Number Temper- Composition atureoC Spray Dwell Blow-Off 1 30 10 30 54.4 Aqueous H 2

SO

4 to give pH 2.

2 90 10 30 60.0 See Notes for this table below.

3 30 10 30 22 +4 Tap Water.

4 20 20 30 37.8 Varies; see details below.

5 30 0 0 22+4 Tap water rinse.

6 90 0 30 22+4 DI water rinse.

Notes for Table 2 The composition for Stage 2 contained commercially available sulfuric acid and surfactant cleaner (RIDOLINE® 124-C from the Parker+Amchem Div. of Henkel Corp., Madison Heights, Michigan) at a concentration to give 3.4 grams per liter of total surfactant and (ii) hydrofluoric acid, and if needed, additional sulfuric acid to give a free acid value of 15 points and a fluoride ion activity reading of -10 mv, using the Orion instrument and associated electrodes as described in the main text above. The free acid points are determined by titrating a 10 milliliter (hereinafter often abbreviated sample of the composition, dissolved in about 100 ml of distilled water, with 0.10 N NaOH solution, using a phenolphthalein indicator after dissolving a large excess of sodium fluoride (about 2-3 ml bulk volume of powdered dry reagent) in the sample before titrating. The points of free acid are equal to the number of ml titrant required to reach a faint pink end point.

Stage 4 compositions were prepared either by dilution of concentrate or directly from the ingredients. Concentrate compositions, either single or two package, are defined in connection with the particular examples below.

Cans washed and rinsed according to the six stage process described above were dried for 5 minutes at 150 0 C under normal conditions. When heat resistant mobility was being tested, the cans, after the normal drying noted immediately above, were placed in a 200 0 C oven for an additional 5 minutes.

These two drying conditions were identified as single and double baked cans, respectively.

All determinations of coefficient of friction were made in the manner described in lines 44 65 of U.S. Patent 4,944, 889 and were the average of i individual measurements.

Example and Comparison Example Group 1 To test the heat stability of concentrates according to the invention, 1000 grams of single package concentrate were made up and placed in a constant D temperature water bath controlled to 48.9±0.6 0 C (120±1OF) Fifty milliliter (hereinafter often abbreviated as samples were removed and diluted to 8 liters (hereinafter often abbreviated for use in the Stage 4 bath. Prior to *Wb** o .addition of the substrate cans, 9.6 grams of aluminium sulfate 100 ppm of AI+3) were dissolved in the Stage 4 bath. Before addition of the final amount of water, the fluoride activity was adjusted to -90 my vs Activity Standard Solution 120 E (commercially available from P+A) and the pH to 2.7 to the addition of concentrated aqueous sulfuric and/or hydrofluoric acid if needed. A set of 14 cans was washed and dried about once each week. The COF of the washed and dried cans was measured and if the value was 1.0, the primary concentrate was returned to the water for another week.

The compositions of the single package type concentrates used for this group are shown in Table 3, except that the particular ingredients used for component or a comparison with it in this group of experiments are shown in Table 4, as are the coefficients of friction obtained with freshly made working 17 compositions using these ingredients, and the weeks of stability of the concentrates obtained with these ingredients. More detailed data from which the lifetime data in Table 4 were derived are shown in Table Table 3 GENERAL COMPOSITION OF CONCENTRATE USED TO PREPARE WORKING SOLUTIONS FOR EXAMPLE AND COMPARISON EXAMPLE GROUP 1 Component Grams of Component per Kilogram of Concentrate Component or other phosphorus-containing 120.6 surfactant.

Fluozirconic acid 35.7 Ammonium bifluoride 6.3 IGEPAL® CO-887 7.7 Deionized water balance Notes for Table 3

A

IGEPAL® CO-887 is commercially available from Rhone-Poulenc Corp, Cranbury, New Jersey 08512, USA, and is reported to contain as its active ingredient ethoxylated nonyl phenols.

@06* 0e 0 0e 0 0 S. 0 0

S

S.

S

S

0555 p.

S

p Table 4 PHOSPHATE COF SB COF DB WEEKS COMMENTS ESTER

STABLE

AT 48.90 C ETHOX® 2684 0.527 0.967 3-4 PHOSPHO- 0.576 0.635 13 TERIC® TC-6 PHOSPHO-.7

N

TERIC® 0.727 NA 8

TERIC®

TL-3K TRYFAC® 0.583 0.698 NA Severe water 5560 break Notes for Table 4 "SB" single bake; "DB" double bake; "NA" not available. ETHOX® 2684 commercially available from Ethox Chemicals, Inc., Greenville, South Carolina 20606, USA, is reported by its supplier to be a monoesterified phosphoric acid with the alcohol moieties derived from a mixture of C 8 -1o linear monoalcohols condensed with an average of about 6 moles of ethylene oxide per mole of alcohol.

PHOSPHOTERIC® TC-6 and TL-3K are available from Mona Industries, Patterson, New Jersey and are both reported by their supplier to be carboxyethylphosphoimidazole salts with long substituents (group R3 in formula above); the former is a sodium salt with long alkyl substituents derived from natural coconut oils and the latter is a potassium salt with its long alkyl substituents being lauryl groups.

TRYFAC® 5560 is commercially available from Henkel Corporation.

Table EFFECT OF STORAGE TIME AT 48.90 C ON ABILITY OF COMPOSITIONS IN EXAMPLE AND COMPARISON

EXAMPLE

GROUP 1 TO REDUCE THE COEFFICIENT OF FRICTION

ON

ALUMINIUM

CANS

Days of Storage at Coefficient of Friction after Noted Time with: Temperature ETHOX® PHOS-

PHOS--

2684 PHOTERIC®

PHOTERIC®

TL-3K TC-6 1 0.55 0.60 0.58 1 5 9 0.62 0.61 0.58 16 0.87 0.72 0.58 22 0.92 0.70 0.58 29 1.39 0.65 0.58 36 0.65 0.58 20 43 0.92 0.58 nm 0.58 0.78 0.58 64 0.80 0.58 71 0.58 78 0.58 92 0.58 The severe water breaks observed with TRYFAC® 5560 would seriously limit its commercial acceptability. The other three materials are all commercially satisfactory when freshly made, but the two PHOSPHOTERIC® materials according to the invention last considerably longer in hot storage than the ETHOX® material.

Examples Group 2 In this group, only PHOSPHOTERIC® TC-6 material (as described under Group 1) was used as component The single package type concentrate had the same composition as when made with this particular component for Group 1, but the amount of concentrate used to make the working solutions was varied to include lower amounts than in Group 1. Table 6 shows the resulting concentrations in the concentrate and in the least dilute of the five working concentrations employed in this group, and Table 7 shows the effect of varying the concentration of concentrate in the working Stage 4 composition. The 10 volumes of concentrate shown in Table 7 were diluted with DI water to make 8 L of working solution, after additions of aluminium salt and adjustment of pH and free fluoride activity values if needed, as described for Group 1. The results indicate that there is little difference in the results achieved at any of these concentrations under ideal drying conditions, corresponding to single bake values in the Table, but that three lower values in the Table produce working compositions that are less tolerant of extraordinary heating of the treated cans during processing.

*Table 6 INGREDIENTS, THEIR MOLECULAR WEIGHTS, AND CONCENTRATIONS FOR EXAMPLE GROUP 2 Ingredient Approximate Moles per Moles per Molecular Kilogram in Liter in Weight Concentrate Working Composition PHOSPHOTER- 1125 0.0375 0.000234 IC®TC-6 w/o Active) Fluozirconic 207 0.0776 0.000485 Acid (45% Active) Ammonium 57 0.1105 0.00069 0.00138 gram atoms of

F)

GEPAL® CO-887 1540 0.005 0.000031 Table 7 EFFECT OF CONCENTRATE COMPOSITION ON COEFFICIENT

OF

FRICTION VALUES OBTAINED WITH NORMAL AND EXTRAORDINARY

HEATING

Milliliters of Concentrate COF-SB

COF-DB

0.600 0.731 0.597 0.725 30 0.615 0.848 0.705 0.885 10 0.634 1.074 Examples Group 3 In this group, two package type concentrates were used. The primary concentrate contained 120.5 grams of PHOSPHOTERIC TC-6 per kilogram of concentrate and in some cases also contained 7.6 grams of one of TRYCOL® LF-1 and TRITON® DF-16, which are both alkyl polyethers commercially available from Henkel Corporation and Union Carbide respectively; in some Si cases, the primary concentrate contained no surfactant, other than component in all cases, the balance of the primary concentrate was DI water. The secondary concentrate consisted of 44.7 grams of ammonium bifluoride and 34.5 grams of fluozirconic acid per kilogram of secondary concentrate, with the balance DI water. An amount of 50 mL of primary concentrate was used in each case, along with an equal amount or half of an equal amount of the secondary concentrate. The mixed primary and secondary concentrates were diluted with DI water to 8L, after additions of aluminium salts and adjustment of the pH and free fluoride values to the same levels as in the preceding Groups. The amount and type of surfactants and of primary and secondary concentrates used are shown in Table 8, as are the COF values and the turbidity of the solution. The composition with alternative surfactants had less turbidity and were also less inclined toward undesirable foaming during use than those made with no surfactant other than component or with EGEPAL® CO-887.

Table 8 RESULTS FROM EXPERIMENT GROUP 3 Ratio by Surfactant COF SB COF DB Turbidity Weight of Primary to Secondary Concentrate 1:1 None 0.659 0.853 Cloudy 1:1 DF-16 0.593 0.736 Slightly Cloudy 1:1 LF-1 0.611 0.669 Slightly Cloudy 2:1 None 0.612 0.831 Cloudy 2:1 DF-16 0.562 0.779 Slightly Cloudy 2:1 LF-1 0.573 0.694 Slightly Cloudy

Claims (11)

1. A process including the steps of cleaning a formed metal container, preferably an aluminium can or tin-plated steel can, with an aqueous acidic or alkaline cleaning solution, (ii) subsequently contacting at least one exterior surface of the cleaned metal container with an aqueous lubricant and surface conditioner forming composition, (iii) drying the metal container after steps (i) and and (iv) subsequently conveying the cleaned and dried can via automatic conveying equipment to a location where it is lacquered or decorated by printing or both, wherein the aqueous lubricant and surface conditioner includes a dissolved phosphorus containing surfactant component that is a mixture of molecules conforming to the general formula I: Y R)x O=P (OM) where M is selected from the group consisting of H, alkali metal cations, monovalent fractions of alkaline earth metal cations, and monovalent fractions of ammonium and substituted ammonium cations; x=1 or 2 and y=3-x; Y is an alkylene or alkylene ether group, which may be branched or unbranched, with its open valences on carbon atoms and with from 2 to 12 carbon atoms and up to 3 oxygen atoms; and R is an imidazoline moiety conforming to general formula II: N N (II), R 3 -C R 1 R 2 24 where each of R1 and R2 is independently selected, except that R1 and R2 may not both be hydrogen, from the group consisting of hydrogen, a moiety derived from propionitrile by removing a hydrogen atom from the -CH 3 group thereof, and moieties of the general formula III: -CH 2 CH 2 C-Q (I II O where Q is selected from the group consisting of -OM, -NH 2 and -OR4, where M has the same meaning as defined above and R4 represents C2 12 alkyl, alkylaryl, or alkylcycloaliphatic moiety; and R3 is selected from the group consisting of unsubstituted and hydroxy substituted aliphatic and cycloaliphatic and alkylaryl moieties having from 2 to 22 carbon atoms; a component selected from the group of water soluble salts containing ions that comprise atoms selected from the group consisting of Zr, Ti, Sn, Al, and Fe; a metal etching component; and "free fluoride ions"; and, optionally, any one or more of the following: a component selected from molecules conforming to general formula IV: R 6(IV), R 6 O-(-CH CH 2 O)s- X wherein R6 is a linear, cyclic, or branched saturated monovalent aliphatic hydrocarbon moiety containing from 1 to 25 carbon atoms; X is selected from the group consisting of hydrogen, halogen, phenyl, and R5; s is an integer from 1 to and R5 is selected form the group consisting of hydrogen and alkyl groups containing 1-4 carbon atoms; a component selected from molecules conforming to general formula V: R s I R 7 (C 6 H4) O- CH- CH 2 O)s- H wherein R 7 is a linear, cyclic, or branched saturated monovalent aliphatic hydrocarbon moiety containing from 4 to 25 carbon atoms; (C 6 H 4 is an ortho- meta, or para-phenylene nucleus; and R 5 and s have the same meaning as for formula IV; a component selected from molecules conforming to general formula VI: 0 R C-O- CH-CH O) s-H (VI) wherein R 8 is a linear or branched, saturated or unsaturated monovalent aliphatic hydrocarbon moiety containing from 1 to 25 carbon atoms; and R 5 and Ss have the same meaning as in formula IV; a component selected from chelating agents for the metal containing ions of component and a microbial agent.

2. A process according to claim 1, wherein the lubricant and surface conditioner forming composition has a pH from 1 to 8, wherein the amount of component is such as to provide from 0.000012 to 0.005 gram atoms of phosphorus per liter of composition; the amount of component is such as to provide from 0.00002 to 0.005 gram atoms of a total of Zr, Ti, Sn, Al, and Fe per liter of composition; the fluoride ion activity is such as to result in a fluoride ion activity meter reading within the range from -50 to -130 my; component is selected from molecules conforming to general formula I when the groups y ,ontain from 2 to 4 carbon atoms and no oxygen atoms, R 1 and 26 R 2 are selected from the group consisting of hydrogen and moieties of general formula III when Q=OM and M is hydrogen or an alkali metal, and at least mole percent of the total R 3 groups in the composition have from 8 to 20 carbon atoms.

3. A process according to claim 2, wherein the amount of component is such as to provide at least 0.000025 gram atoms of phosphorus per liter of composition; the amount of component is such as to provide at least 0.000042 gram atoms of the total of Zr, Ti, Sn, Al and Fe per liter of composition; the fluoride ion activity is such as to result in a fluoride ion activity meter reading *within the range from -60 to -120 my; and the concentration of fluorine atoms in o*o* ingredients of the composition selected from the group consisting of fluoride ions, bifluoride salts, and hydrogen fluoride is at least 0.000051 gram atoms per :*:liter of fluorine atoms.

4. A process according to claim 3, wherein the pH is in the range from 2.0 to the amount of component is such as to provide from 0.000051 to 0.001 "gram atoms of phosphorus per liter of composition; component includes dissolved fluozirconic acid, fluozirconate ions, or both fluozirconic acid and .fluozirconate ions; and the amount of component is such as to provide at least 0.000097 gram atoms of Zr per liter of composition. A process according to claim 4, wherein component is selected from molecules conforming to general formula I when Y is an ethylene group and at least 76 mole percent of the total R 3 groups have from 10 to 14 carbon atoms and are unsubstituted and unbranched alkyl groups; the amount of component is such as to provide at least 0.00019 gram atoms of phosphorus per liter of composition; the amount of component is such as to provide at least 0.00038 gram atoms of Zr per liter of composition; the amount of component is such as to provide from 0.001 to 0.025 gram atoms per liter of hydrogen ions and from 0.002 to 0.050 gram atoms per liter of fluoride atoms; and the amount of component is in the range from 0.001 to 0.01 by weight.

6. A process according to claim 5, wherein the amount of component is such as to provide no more than 0.00059 gram atoms of the total of Zr, Ti, Sn, Al, and Fe per liter of composition, and the fluoride ion activity is such as to result in a fluoride ion activity meter reading within the range from -75 to -105mv.

7. A process according to claim 6, wherein the nature and amount of component are such as to provide from 0.00038 to 0.00059 gram atoms of Zr per liter of composition, and the amount of component is such as to provide from 0.006 to 0.014 gram atoms per liter of fluoride atoms.

8. A process according to any one of claims 1 to 7, wherein the cleaning of the metal container is accomplished by contact with an acidic cleaning "°o**composition having a fluoride ion activity indicated by a fluoride sensitive **electrode reading in the range from +50 to -10 my. A liquid composition of matter consisting essentially of water and: *o a dissolved phosphorus containing surfactant component that is a mixture of molecules conforming to the general formula I: Y R)X 0=P (OM)y where M is selected from the group consisting of H, alkali metal cations, monovalent fractions of alkaline earth metal cations, and monovalent fractions of ammonium and substituted ammonium cations; x= 1 or 2 and y Y is an alkylene or alkylene ether group, which may be branched or unbranched, with its open valences on carbon atoms and with from 2 to 12 carbon atoms and up to 3 oxygen atoms; and R is an imidazoline moiety conforming to general formula II: N (II), Y R3-C R 1 R 2 where each of R 1 and R 2 is independently selected, except that R 1 and R 2 may not both be hydrogen, from the group consisting of hydrogen, a moiety derived from propionitrile by removing a hydrogen atom from the -CH 3 group thereof, and moieties of the general formula III: -CH 2 cCH 0 where Q is selected from the group consisting of -OM, -NH 2 and -OR 4 where M has the same meaning as defined above and R 4 represents C2 12 alkyl, alkylaryl, or alkylcycloaliphatic moiety; and R 3 is selected from the group consisting of unsubstituted and hydroxy substituted aliphatic and cycloaliphatic and alkylaryl moieties having from 2 to 22 carbon atoms; a component selected from the group of water soluble salts containing ions that comprise atoms selected from the group consisting of Zr, Ti, Sn, Al, and Fe; a metal etching component; and "free fluoride ions"; and, optionally, any one or more of the following: a component selected from molecules conforming to general formula IV: R R 6(IV), R 6 -O-(-CH-CH 2 -O)s-X wherein R 6 is a linear, cyclic, or branched saturated monovalent aliphatic hydrocarbon moiety containing from 1 to 25 carbon atoms; X is selected from the group consisting of hydrogen, halogen, phenyl, and R 5 is an integer from 1 to and R 5 is selected from the group consisting of hydrogen and alkyl groups containing 1 4 carbon atoms; a component selected from molecules conforming to general formula V: R SR 7 -(C 6 H 4 CH CH O H wherein R 7 is a linear, cyclic, or branched saturated monovalent aliphatic hydrocarbon moiety containing from 4 to 25 carbon atoms; (C 6 H 4 is an ortho-, meta-, or para-phenylene nucleus; and Rs and s have the same meaning as for formula IV; a component selected from molecules conforming to general formula VI: 0 R 8 -C-O-(-CH-CH 2 O) -H (VI) wherein R 8 is a linear or branched, saturated or unsaturated monovalent aliphatic hydrocarbonoiety containing from 1 to 25 carbon atoms; and R 5 and s have the same meaning as in formula IV; a component selected from chelating agents for the metal containing ions of component and an antimicrobial agent. A composition according to claim 10 wherein the amount of component is such as to provide from 0.000060 to 5 gram atoms of phosphorus per liter of composition; the amount of component is such as to provide from 0.00010 to 5 gram atoms of the total of Zr, Ti, Sn, Al, and Fe per liter of composition; component is selected from molecules conforming to general formula I when the groups contain from 2 to 4 carbon atoms and no oxygen atoms, R 1 and R 2 are selected from the group consisting of hydrogen and moieties of general formula UI when Q OM and M is hydrogen or an alkali metal, and at least mole percent of the total R 3 groups in the composition have from 8 to 20 atoms. I

11. A composition according to claim 11, wherein the amount of component t*9o04 is such as to provide at least 0.0010 gram atoms of phosphorus per liter of composition; the amount of component is such as to provide at least 0.0017 gram atoms of the total of Zr, Ti, Sn, Al, and Fe per liter of composition; and the concentration of fluorine atoms in ingredients of the composition selected from the group consisting of fluoride ions, bifluoride salts, and hydrogen fluoride is at •least 0.0020 gram atoms per liter of fluorine atoms.

12. A composition according to claim 12, wherein the amount of component is such as to provide from 0.0010 to 0.40 gram atoms of phosphorus per liter of composition; component includes dissolved fluozirconic acid, fluozirconate ions, or both fluozirconic acid and fluozirconate ions; and the amount of component is such as to provide at least 0.0039 gram atoms of Zr per liter of composition.

13. A composition according to claim 13, wherein component is selected from molecules conforming to general formula I when Y is an ethylene group and at least 76 mole percent of the total R 3 groups have from 10 to 14 carbon atoms and are unsubstituted and unbranched alkyl groups; the amount of component is such as to provide at least 0.020 gram atoms of phosphorus per liter of composition; the amount of component is such as to provide at least 0.0040 gram atoms of Zr per liter of composition; the amount of component M is such as to provide from 0.21 to 11 gram atoms per liter of fluoride atoms; and the amount of component is in the range from 0.10 to 2.2 by weight.

14. A composition according to claim 14, wherein the nature and amount of component are such as to provide from 0.057 to 0.103 gram atoms of Zr per liter of composition, and the amount of component is such as to provide from 0.9 to 2.4 gram atoms per liter of fluoride atoms. DATED this 5th day of January, 1998 HENKEL CORPORATION WATERMARK PATENT TRADEMARK ATTORNEYS 4TH FLOOR, "DURACK CENTRE" *..263 ADELAIDE TERRACE PERTH W.A. 6000 AUSTRALIA *6 0 S *fee es e S.IO