CA1075673A

CA1075673A - Hot melt metal working lubricants

Info

Publication number: CA1075673A
Application number: CA328,952A
Authority: CA
Inventors: Richard W. Jahnke
Original assignee: Lubrizol Corp
Current assignee: Lubrizol Corp
Priority date: 1974-10-10
Filing date: 1979-06-01
Publication date: 1980-04-15

Abstract

ABSTRACT OF THE DISCLOSURE
Metal working operations, especially drawing, are facilitated by applying to the metal a composition which provides lubricity thereto and which melts at about 30-100°C.
The composition comprises an ester of a carboxylic acid, with a carboxylic acid or derivative thereof, a phosphorus acid salt and an antioxidant being preferred optional ingredients.
The composition may be applied in liquid form and solidifies on cooling to ambient and normal storage temperatures. Prior to application, the composition is preferably heated to a temperature higher than its melting temperature for ease of flow and uniform dispersion thereof onto the metal. In a preferred method of application, a reservoir is located beneath the composition applicator and composition is pumped therefrom to the applicator, preferably a roller coater, with excess composition being recirculated. Steam may be used both to heat the compositions to melting point and purge the pump and circulation piping at the start and finish of each run.

Description

1~75~73 This invention relates to metal working operations.
More particularly, it relates to compositions useful as lubri-cants during such operations.
Metal working operations, for example, rolliny, - forging, hot-pressing, blanking, bending, stamping, drawing, cutting, punching, spinning and the like generally employ a lubricant to facilitate the same. Lubricants greatly improve these operations in that they can reduce the power required for the operation, prevent sticking and decrease wear of dies~ -cutting bits and the like. In addition, they frequently provide rust inhibiting properties to the metal being treated.
Since it is conventional to subject the metal to various chemical treatments (such as the application of con-version coating solutions) after working, a cleaning operation is necessary between the working step and the chemical treat-ment step. In addition to the above properties, therefore, it is preerred that the working lubricant be easily removable from the metal surface by ordinary cleaning compositions.
Heretofore, the lubricants applied for the above purposes have ordinarily been liquids. The equipment used for the application of such liquids is often expensive to maintain and inconvenient to use. In addition~ a dry-off oven is usually required to remove the water or solvent carrier from the liquid composition, which also greatly adds to the capital costs and operating and maintenance expenses of the method~
Difficulties are also often encountered in automatic feeding of metal blanks and otherwise handling the metal because the liquid compositions which are normally applied to the metal make it wet and slippery a~d consequen-tly difficult to handle.

~ , . ~ . .
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, ~ ' 3~75~73 ~ principal object of the present invent.ion, therefore, is to provide novel compositions for use in an improved metal working method.
A further object is to provide these compositions as lubricants which impart to the metal being worked a unique combination of properties including lubricity, corrosion resistance, extreme pressure properties and protection against wear of working parts, and which in addition are relatively easy to remove from the surface of the metal by cleaning after the working operation is completed.
Another object is to provide a method by which a solid metal working composition can be melted and applied to the metal, thereby eliminating the need or dry-off ovens and their attendant drawbacks, Still another object is to provide a method by which the composition, after application to the metal, solidi fies to produce a non-blocking and reIatively non-slippery ilm, thus allowing consistent and economical automatic feeding of blanks and material hanaling at reduced costs.
A still urther object is to provide a method which permits the formation of a solid ~ilm o metal working composition on the surface of a metal workpiece by applying the melted composi~ion to the metal surface while the latter :
(e.g., as wire, tubing or the like) is moving through the application means at relatively high speed.

-2-~1~17S~i73 Other objects will in part be obvious and will in part appear hereinafter.
According to this invention, the above objects are fulfilled by applying to the metal to be worked a composition which provides lubricity thereto and which comprises an ester of a carboxylic acid, said composition melting at about 30 -100C. Preferably, the composition melts to form a readily flowable liquid which is capable of easy and efficient appli-cation to the metal surface. One advantage of such a composi-tion (sometimes referred to hereinafter as the "hot meltcomposition'') is that metals coated therewith are easier to handle under normal storage conditions than metals coated with previously known lubricants.
The principal necessary characteristic of the hot melt composition is its capability of providing lubricity to the metal surface. For this purpose, lubricity ma~ be defined in many ways which are well known to those skilled in the art, and in terms of a number of test methods which, in one way or another, simulate metal working operations. For the purpose of this invention, a composition is deemed to provide lubricity to a metal workpiece if its use resul~s in a deviation of 100 foot-pounds or less when tested by the following method:
A cold-rolled steel strip, 2" x 13 l/2", is drawn between two dies in an Instron Universal Tester, Model TT-C.
Prior to drawing, the edges of the strip are deburred and the strip is vapor degreased and wiped with a clean cloth. It is then cGated uniformly with a drawing lubricant and mounted in the testing machine. The dies are tightened by means of a torque ~rench set at 40 foot-pounds torque and the strip is pulled through the die for two inches at the rate of five inches per minute. The force or "load!', in foot pounds, ~`

required to pull the strip through the die r and the deviation from a uniform load, are recorded on a chart.

~ 37S6~3 The hot melt composition melts in the range of 30 -100C., as previously indicated. Thus, it is normally solid at ambient temperature and pressure. The preferred melting range is 35 - 70C., with 38 - 55C. being par-ticularly desi-rable. When melted, the composition pre~erably ~orms a readily flowable liquid.
The principal ingredient of the hot melt composition is an ester o~ a carboxylic acid. (When used herein, the sin-gular forms "a", "an", and "the" include the plural unless the context clearly dictates otherwise; thus, for example, "an ester" includes a mixture of two or more esters.) Typical esters are those of acids havin~ the formula R(COOH)m and organic hydroxy compounds having the formulaR'(OH)n, wherein each of m and n is an integer from 1 to 3 and each of R and R' is a hydrocarbon-based radical. As used herein, the term "hydrocarbon-based radical" denotes a radical having predomi-nantly hydrocarbon character within the context of this inven-tion. Such radicals include the following:
(1) Hydrocarbon radicals, which may be aliphatic (e.g., alkyl or alkenyl), alicyclic (e.g., cycloalkyl or cycloalkenyl), aromatic, aliphatic- and alicyclic-substituted ~ ;
aromatic, aromatic-substitu-ted aliphatic and alicyclic, and the like.
(2) Substituted hydrocarbon radicals, that is, ;
radicals containing non-hydrocarbon substituents which, in the context of this invention, do not alter the predominantly hydrocarbon character of the radical. Suitable substituents of this type will be apparent to those skilled in the art.

(3) Hetero radicals; that is, radicals which, while predominantly hydrocarbon in character within the context of this invention, contain atoms other than carbon present in a chain or ring otherwise composed of carbon atoms. Suitable hetero atoms will be apparent to those skilled in the art and .. . .

include~ for example, nitrogen, oxygen and sulfur.
In general, no more than about three substituents or hetero atoms, and preferably no more than one, will be present for each 10 carbon atoms in the hydrocarbon-based radical.
The acids and organic hydroxy compounds are usually those in which R and R' are free from acetylenic and conjugated diene unsaturation and preferab~y contain no more than one olefinic double bond. Most often, there is no more than one such olefinic double bond per ester molecule.
The acid typically contains about 4 - 20 carbon atoms.
The preferred acids are the aliphatic polycarboxylic acids, especially those in which m is 2 or 3 and R is an alkyl or alky-lene radical, which may be branched or linear. Exemplary acids are propionic, butyric, stearic, oleic, benzoic, maleic, fuma-ric, succinic, adipic, glutaric, pimelic, sebacic, azelaic, suberic, phthalic, isophthalic, citric and trimellitic acids.
The particularly preferred acids are the aliphatic dicarboxylic acids hauing about 5 - 10 carbon atoms.
The organic hydroxy compound typically contains at least about 10 and generally about 10 - 25 carbon atoms.
Usually, n is 1 and R' is an alkyl radical which may be bran-ched or linear. Exemplary organic hydroxy compounds are 1-butanol, 2-buten-1-ol, phenol, resorcinol, ethylene glycol, diethylene glycol, decanol, dodecanol, tetradecanol, stearyl alcohol, oleyl alcohol, eicosanol, and commercial mixtures of such alcohols. The preferred alcohols are satura-ted aliphatic alcohols containing at least about 10 carbon atoms, especially C14 20 alkanols (that is, saturated monohydroxy alcohols) and more especially predominantly straight-chain alkanols.
From the above descriptions of suitable acids and organic hydroxy compounds, it will be apparent that a wide variety of carbo~ylic acid esters are contemplated for use according to this invention. These include both neutral esters _5 _ ~at7~673 and acidic esters (e.g., monoesters of dicarboxylic acids), but neutral esters are preferably used. Both mono- and bis-esters of polyhydroxy compounds are contemplated. Especially preferred are the neutral esters o adipic, azelaic or sebacic acid and C14_20 predominantly straight-c-hain alkanols or com-mercial mixtures of such alkanols.
The preferred hot melt compositions contain, in addi-tion to the esters described hereinabove, one or more rust inhibiting components and/or agents to lmprove extreme pressure properties.
Among the suitable rust inhibiting materials are carboxylic acids and derivatives thereo~. The term l'derivati~e"
as used herein with reference to such carboxylic acids includes:
Anhydrides.
Esters (acidic or neutral), especially those prepared from lower saturated aliphatic (the word "lower" meaning up to 7 carbon atoms monohydroxy or polyhydroxy compounds (e.g., methanol, ethanol, l-butanol, n-hexanol, ethylene glycol, pentaerythritol) or epoxides (e.g., ethylene oxide, propylene oxide). The epoxide-derived esters as will be readily understood, are hydroxy esters.
It will be appreciated that i the "derivative"
is an ester, the hot melt composition comprises at least two esters.
Salts (neutral, acidic or basic) in which th cation is a Group I me*al, a Group II metal, aluminum, tin, cobalt, lead, molybdenum, manga-nese, nickel or ammonium (the latter including substituted ammonium, i.e. amine) including salts o the ree acids and of their hydroxy esters. The lithium salts are preerred or ' :~

ilLt3756~3 their antirust properties.
Amides and amide-imide mixtures, especi-ally those derived from aliphatic amines and more especially from lower aliphatic amines.
The preferred amines are the alkylene poly-amines, particularly ethylene polyamines.
Verivatives of the type described above may be ob-tained from the acids by known reactions or sequences of reactions.
The free acids, their lithium salts, and their an-hydrides are most useful. Preferred are the aliphatic mono-and polycarboxylic acids (and derivatives thereof as defined hereinabove) containing at least about 8 carbon atoms. Parti-cularly desirable are the dibasic acids, especially the anhy-; drides of succinic acids having a hydrocarbon-based substi-tuent (as defined hereinabove), such as those prepared by the reaction (more fully described hereinafter) of maleic acid or maleic anhydride with a hydrocarbon-based compound containing at least about 6 carbon atoms, preferably about 6 - 75 and most often about 10 - 20 carbon atoms.
The hydrocarbon-based compounds preferred for -the preparation of the substituted succinic acid are those derived from substantially saturated petroleum fractions and olefin polymers, particularly oligomers of monoolefins (especially terminal monoolefins) having from 2 to about 10 carbon atoms.
Thus, the hydrocarbon-based compound may be derived from a ., polymer of ethylene, propene' l-butene, 2-butene, isobutene, 3-pentene, l-octene or khe like. Also useful are interpolymers of olefins such as those illustrated above with other polymeriz-. ~ .
able olefinic substances such as styrene, chloroprene, isopre~e p-methylstyrene, piperylene and the like. In general, these interpolymers should contain at least about 80%, preferably . .
at least about 956, on a weight basis of units derived from the ':

; . .. . . ,:

~7~56~3 aliphatic monoolefins.
Other suitable hydrocarbon-based compounds are mix-tures of saturated aliphatic hydrocarbons such as highly refined high molecular weight white oils or synthetic alkanes.
In some instances, the hydrocarbon-based compound should contain an activating polar radical to facilitate its reaction with the low molecular weight acid-producing compound.
The preferred activating radicals are halogen atoms, especially chlorine, but other suitable radicals include sulfide, disul-fide, nitro, mercaptan, ketone and aldehyde groups.
As previously noted, the preferred method for pro-ducing the carboxylic acid or deri~ative thereof is by the reaction of maleic acid or anhydride with the hydrocarbon-based compound, especially with a material such as a propene oligo-m~r. This reaction in~olves merely heating the two reactants at about 100 - 200C. in the presence or absence of a substan-tially inert organic liquid diluent; an excess of a liquid reactant may also serve as the reaction medium. Other suitable reactions include oxidation with potassium permanganate, nitric acid or a similar oxidizing agent of a hydrocarbon-substituted 1,4-butanediol or the like; ozonolysis of a hydrocarbon-substituted 1,5-diene or the like; preparation of a bis-organometallic derivative of a hydrocarbon-substituted 1,2-dihalide or the like, followed by carbonation thereof with carbon dioxide; or preparation of a dinitrile followed by its hydrolysis. All of -these reactions are well known in the art, as are the substituted succinic acids and derivatives thereof produced thereby.
The preferred extreme pressure agents are phosphorus acid salts of the formula Rl~Xl) ~ P-X4M

b .

,-,,:

~75673 wherein M is a Group I metal, a Group II metal, aluminum, tin, cobalt, lead, molybdenum, manganese, nickel or ammonium, each of Rl and R2 is a hydrocarbon-based radical; each of Xl, X , X3 and X4 is oxygen or sulfur; and each of a and b is 0 or 1.
In the above formula, each of Rl and R2 is a hydrocarbon-based radical. Preferably, they are free from acetylenic and usually also from ethylenic unsaturation and have no more than about 30 carbon atoms, desixably no more than about 12 carbon atoms. They are usually hydrocarbon radicals such as methyl, ethyl, propyl, butyl, amyl, hexyl, octyl, decyl, dodecyl, vinyl, decenyl, cyclohexyl, phenyl and the like, all isomers thereof being included. A particular preference is expressed for compounds in which Rl and R2 are lower alkyl radicals, the word "lower" being defined hereinabove.
It will be apparent that the phosphorus acids from which the salts are derived in~ude dialkylphosphoric acids, dialkylphosphinic acids, and thio derivatives of such acids.
Especially preferre~ are the salts of phosphorodithioic acids;
that is, compounds in which a and b are each 1, Xl and x2 are ; 20 each oxygen, and X3 and X4 are each sulfur. In these salts, M may be any of the metals previously enumerated or ammonium:
the later term includes substituted ammonium salts (i.e., amine salts). M is preferably zinc or lead, especially zinc.
The hot melt composition most often contains up to abou~ 15% by weight of the carboxylic acid or derivative there-of and/or up to about 25% of the phosphorus acid salt, both of which are optional ingredients. In particular, this invention includes compositions providing lubricity to metal and compri- `
sing an ester of a carboxylic acid and at least one of a car-boxylic acid or derivative thereof and a phosphorus acid salt,each of said components being as defined hereinabove; said compositions melting at about 30 - 100C.
It is also within the scope of this invention to .

~9~

~.~S756'73 incorporate other known additives in minor amounts (typically about 0.01 - 5.0% by weight) into the hot melt composition.
Especially preferred other additi~es are antioxidants, typi-cally hindered phenols; such materials are well known in the art. Other suitable additives include:
Surfactants, usually nonionic surfactants such as oxyalkylated phenols and the like.
Auxiliary extreme pressure agents such as chlorina-ted waxes, sulfurized hydrocarbons, sulfurized esters, etc.
Corrosion and wear inhibiting agents, and auxiliary rust inhibiting agents. .
Friction modifying agents, of which the following are illustrative: Alkyl or alkenyl phosphates or phosphites in which the alkyl or alkenyl group contains about 10 - 40 carbon atoms, and metal salts thereof, especi~ly zinc salts;
C10 20 fatty acid amides; C10_20 alkyl amines, especially tallow amines, and ethoxylated derivati~es thereof; salts of such amines with acids such as boric acid or phosphoric acid which have been partially esterified as noted above; C10 20 alkyl-substituted imidazolines and similar nitrogen hetero-cycles; sulfurized derivatives of sperm oil and other fatty oils; basic barium or calcium salts of such oils or of amine-formaldehyde condensates, especially those derived from tallo~
amines such as described above; and gels derived from basic :.
alkaline earth metal sulfonates.
Melting point modifiers, typically relatively low melting point esters such as dioctyl phthalate.
The hot melt Gomposition may be prepared by intimate-ly blending the ingredien~s thereof, preferably in the liquid 30 state, if more than one ingredient is involved. It may some- -:
times be preferable to employ a substantially inert liquid diluent to insure intimate blending. By "substantlally inert"
is meant a diluent which does not undergo any appreciable ~7~73 reaction with the ingredients of the composition under the conditions of blending. Preferred as diluents are liquids which are solvents Eor the ingredients being blended; suitable solvents will be apparent to those skilled in the art and preferably comprise non-polar liquids such as benzene, toluene, xylene, chlorobenzene and the like. After blending is com-plete, the diluent is preferably removedl, typically by evaporation.
In the following table are listed typical hot melt compositions suitable for use in the method oF this invention.

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~75673 Any metal to be worked may be treated according to the method of this invention; examples are ferrous metals, aluminum, copper, magnesium, titanium, zinc and manganese as well as alloys thereof and alloys containing other elements such as silicon.
The method of this invention includes any method by which a metal workpiece may be coated with the hot melt com-position prior to or concurrently with the wor~ing operation.
For example, a cutting blade or drawing die may be coated with 1~ the composition which is then transferred to the workpiece by contact. More usually, however, the workpiece is coated with the hot melt composition before the working operationO Thus, this invention also contemplates a metal workpiece having on its surface a film of the hot melt composition, whether in solid or liquid form. The hot melt composition will ordinarily form a continuous film over the entire surface of the work-piece. However, it is also within the scope of this invention to form a film on less than the entire surface of the work-piece.
The physical state of the hot melt composition during application to the metal surface is not critical. Thus, it may be applied as a solid (as by rubbing) or as a liquid (as by brushing, spraying, dipping flooding/ roller coating, reverse roller coating or the like). For ease and conv~nience of application, it is preferably applied in the liquid state, and when this is done the metal may be subsequently cooled where-upon the hot melt composition solidifies, or it may be passed directly to the metal working operation while the composition ~-is in the liquid state. One of the advantages of this inven-tion, however, is that the hot melt composition solidifies to form a solid, non-blocking, non-slipper~ film on the metal w~rkpiece, thus permit-ting convenient and safe material hand-ling at reduced cost.

:

56~3 To this end, the present invention also includes a method (hereinafter sometimes referred to as "the application method of this invention") of applying to a metal workpiece a metal working composition, such as the hot melt composition described hereinabove, which is a solid at a~ient temperature and pressure, said method comprising the steps of heating the composition to cause it to melt and maintaining the temperature thereof for ease of flow and uniform dispersion thereof onto the metal, applying the melted composition to the metal work-piece to form a film of such composition thereon, and allowingthe film of said composition to cool and solidify.
The surface temperature of the metal at the time the hot melt composition is applied may vary, for example, from ambient temperature to just below the decomposition temperature thereof. Factors which will influence or determine the temper-ature of the metal at the time the composition is applied in-clude processes which the metal is subjected to prior or subse-quent to application of the composition, the melting point of the composition, and the temperature t~ereof at the time of application. Using the hot melt compositions described herein-above, metal surface temperatures of about 20 - 125C. at the time of application have been found particularly useful. The temperature of the hot melt composition should be higher than its melting temperature (preferably at least 10C. higher and usually about 20 ~ 40C. higher) at the time of application for ease of flow and uniform dispersion of the composition onto the metal and coverage thereby.
The melted hot melt composition may be appiied to the metal in a minimum of space utilizing existing e~uipment such as coilers used in steel mills prior to coiling, and because it quickly solidifies at ambient temperatures ana becomes dry, non-blocking and relatively non-slippery, standard handling equipment such as lifting and feeding rollers. Stackers, and .. , . , , . . ,................ :

~7S6~3 so on may also be used. The application method of this inven-tion also eliminates the need for a dry-off oven since there is no water or solvent to remove from the hot melt composition.
In the annexed drawings:
Figure 1 is a schematic diagram showing a metal pro-cessing line or system including an illustrative apparatus for applying the hot melt composition to a metal workpiece in accordance with application method of this invention;
Figure 2 is an enlarged schematic transverse section through the reservoir and applicator of the apparatus used to coat the metal workpiece with such composition, ta~en on the plane of the line 2-2 of Figure l; and Figure 3 is a partial transverse section on the plane of the line 3-3 of Figure 2.
In Figure l there is schematically shown a metal sheet or strip material processing line L including in the line a preferred apparatus 1 for applying the hot melt composition to the metal workpiece S, which may be in the form o~ strips or sheets of material cut into desired lengths as shown or may consist of a continuous coil of strip material which may either be recoiled after passing through the apparatus or cut into sheets and stacked using conventional uncoilers, recoilers and/or destacker and stacker equipment and the like. Regard-less of the length of the metal workpiece S, it may be trans-ported through the material processing line L on conventional conveyor and feed rolls 3.
In the illustrative coating apparatus shown in Fig-ures 1 and 2, a reservoir 5 ~or the hot melt composition M is located near (pre~erably beneath) the applicator wh:ich applies the composition to the metal. The composition is desirably heated as by passing through heating means such as a steam coil 6 talthough electrical or other heating methods are also suitable) which is usually located in reservoir 5 and which is . .

75~73 adapted to provide good temperature control over a suitablerange such as 30 - 85C., to cause the composition to melt and to remain liquid until after it has been applied to the metal but at the same time to insure against its being heated above its decomposition temperature.
The liquid composition is pumped by pump 15 through circulation piping 11 to the applicator. Pump 15 should, of course, have sufficient capacity to supply liquid composition to the applicator at the desired pressure, e.g., 10 psi, and simultaneously to recirculate a portion of said composition back to the reservoir as described hereinafter.
As previously noted, the applicator may be a spray head, brushing or flooding means, roller coater or the like.
Roller coaters are preferred; the one shown in Figures 2 and 3 comprises two rubber coating rolls 8 (which may be heated), one for coating each side of workpiece S. As shown in Figure 3, doctor rolls 9, in contact with coating rolls 8, can be horizontally adjusted 50 as to regulate the thickness of com-position M on the coating rolls, which themselves may be ver- ;
tically adjusted so as to regulate the amount of said composi-tion transferred to the workpiece S. Drip trays 10 underneath the applicator feed excess hot melt composition back to reser-voir 5.
The flow of hot melt composition M to the applicator may be controlled by means of valves 14. To aid in such con-trol, a por~ion of the flow of such composition through circu-lation piping 11 is desirably caused to bypass the applicator and recirculate to the reservoir 5 through a suitable bypass conduit 12 and valve 13.
The use of steam, especially low pressure steam, as the source of heat for melting and maintaining the temperature of the composition has the advantage that the steam may be introduced into the circulation piping 11 through a conduit -16~

~L6375~73 16 and valve 17 both at the start of a run to preheat the same and also at the finish of a run to prevent composition solidi-fication and buildup therein. Alternatively, circulating pipin~ 11 may be provided with a jacket to permit circulation of steam around it at both the start ancL finish of a run. The discharge line 18 for the steam from steam coil 6 to condensate trap 19 also desirably passes around or through the housing of pump 15 to prevent solidification and accumulation of hot melt composition therewithin.
In addition to, or in place of, the use of an appli-cator (such as that shown in Figure 2) adapted to meter the hot melt composition onto the metal surface, other methocls for regulating the thickness of the film of such composition on the surface may be employed. These include control of the temperature of the composition and/or the metal`, selection of compositions having different melting points (th~lhigher the melting point, the more rapidly solidification will occur and the thicker will be the film thereof, other factors being the same), and regulating the rate of cooling of the metal after the composition has been applied thereto. Film thickness may also be regulated by the use of suitable removal means such as heated squeegee rolls, an air blast of regulated temperature, or the like.
Since the hot melt composition does not contain any water or other solvent, no dry-off oven is required to dry the metal after exiting from the coatin~ apparatus 1. However, a suitable distance should preferably be provided from such exit of the metal from the coating apparatus before the metal is stacked or recoiled to allow the coating of hot melt composi-tion to cool to its solidification temperature to form a solid,usually continuous film on the metal; for example, a distance of 40 feet if the metal is moving at a rate of 6~ feet per minute`. This distance wi~l vary, not only with variations in 5~3 the rate of travel of the metal, but also with variations in the type of thickness of the metal as well as its temperature.
In Figure 1, for instance, there is shown a cleaning bath 25 for cleaning mill oil from the metal with good temperature control over a range such as 35 - 75C.; also a water rinse bath 26 which may have good temperature control over a similar ~:
temperature range. ~djacent the downstream end of the cleaner bath 25 there is desirably provided a pair or squeegee rolls 27 to avoia rinse contaminationO Likewise, similar squeegee rolls 28 are desirably provided adjacent the downstream end of the rinse bath 26, which may be supplemented by an air blast.
The method of this invention, when employed substan-tially as described herein, results in the production of metal ~
workpieces which are adequately lubricated for subsequent wor- ~ :.
king operations, especia~y drawing; protected against rust;
and easily cleanable by commercial cleaning methods. .
, ' . -18-: . . . ., , ~

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A composition which melts within the range of 30-100°C and which provides lubricity to metal surfaces, said composition comprising at least one ester of an aliphatic poly-carboxylic acid having about 4-20 carbon atoms and a hydroxy compound having the formula R'(OH) wherein R' is a hydrocarbon-based radical and n is an integer from 1 to 3, and at least one of a carboxylic acid or derivative thereof and a phosphorus acid salt having the formula wherein M is a Group I metal, a Group II metal, aluminum, tin, cobalt, lead, molybdenum, manganese, nickel or ammonium each of R1 and R2 is a hydrocarbon-based radical; each of X1, X2, X3 and X4 is oxygen or sulfur; and each of a and b is 0 or 1.

2. A composition according to Claim 1, wherein the ester is an ester of a saturated aliphatic alcohol having at least about 10 carbon atoms and an aliphatic polycarboxylic acid having about 4-20 carbon atoms.

3. A composition according to Claim 2, wherein the alcohol is an alkanol.

4. A composition according to Claim 3, wherein the ester is an ester of a C14 20 predominantly straight-chain aliphatic alkanol or commercial mixture of such alkanols and adipic, azelaic or sebacic acid.

5. A composition according to Claim 4, which con-tains said carboxylic acid or derivative thereof.

6. A composition according to Claim 5, wherein the carboxylic acid or derivative thereof is a substituted succinic acid in which the substituent is a hydrocarbon-based substitu-ent, or an anhydride or lithium salt thereof.

7. A composition according to Claim 6, wherein the carboxylic acid or derivative thereof is tetrapropenyl succinic anhydride.

8. A composition according to Claim 4, which contains said phosphorus acid salt.

9. A composition according to Claim 8, wherein M is zinc; each of R1 and R2 is a lower alkyl radical; X1 and X2 are oxygen; and X3 and X4 are sulfur, and a and b are each 1.

10. A composition according to Claim 1, which addi-tionally contains an antioxidant.

11. A composition according to Claim 3, which addi-tionally contains an antioxidant.

12. A composition according to Claim 4, which addi-tionally contains an antioxidant.

13. A composition according to Claim 5, which addi-tionally contains an antioxidant.

14. A composition according to Claim 7, which addi-tionally contains an antioxidant.

15. A composition according to Claim 9, which addi-tionally contains an antioxidant.

16. A method for lubricating metals during working thereof which comprises applying to said metal a composition which provides lubricity thereto and which comprises at least one ester of an aliphatic polycarboxylic acid having about 4 20 carbon atoms and a saturated aliphatic alcohol having at least about 10 carbon atoms, said composition melting within the range of about 35-70°C and said composition additionally containing at.
least one of a carboxylic acid or derivative thereof and a phosphorus acid salt having the formula wherein M is a Group I metal, a Group II metal, aluminum, tin, cobalt, lead, molybdenum, manganese, nickel or ammonium; each R1 and R2 is a hydrocarbon-based radical; each of X1, X2, X3 and X4 is oxygen or sulfur; and each of a and b is 0 or 1.

17. A method for lubricating metals during working thereof which comprises applying to said metal a composition which.
provides lubricity thereto and which comprises at least one ester of an aliphatic polycarboxylic acid having about 4-20 carbon atoms and a saturated aliphatic alcohol having at least about 10 carbon atoms, said composition melting within the range of about 35-70°C and said composition additionally containing a carboxylic acid or derivative thereof.

18. A method according to claim 17 wherein the alcohol is an alkanol.

19. A method according to claim 18 wherein the ester is an ester of a C14-20 predominantly straight-chain aliphatic alkanol or commercial mixture of such alkanols and adipic, azelaic or sebacic acid.

20. A method according to claim 19 wherein the working comprises drawing.

21. A method according to claim 17 wherein the carboxylic acid or derivative thereof is a substituted succinic acid in which the substituent is a hydrocarbon-based substituent, or an anhydride or lithium salt thereof.

22. A method according to claim 21 wherein the carboxylic acid or derivative thereof is tetrapropenyl succinic anhydride.

23. A method according to claim 22 wherein the working comprises drawing.

24. A method for lubricating metals during working thereof which comprises applying to said metal a composition which provides lubricity thereto and which comprises at least one ester of an aliphatic polycarboxylic acid having about 4-20 carbon atoms and a saturated aliphatic alcohol having at least about 10 carbon atoms, said composition melting within the range of about 35-70°C and said composition additionally containing a phosphorus acid salt having the formula wherein M is a Group I metal a Group II metal, aluminum, tin, cobalt, lead, molybdenum, manganese, nickel or ammonium; each R1 and R2 is a hydrocarbon-based radical; each of X1, X2, X3 and X4 is oxygen or sulfur; and each of a and b is 0 or 1.

25. A method according to claim 24 wherein M is zinc;
each of R1 and R2 is a lower alkyl radical; X1 and X2 are oxygen; X3 and X4 are sulfur; and a and b are each 1.

26. A method according to claim 25 wherein the working comprises drawing.

27. A method according to claim 17 wherein the composition additionally contains a phosphorus acid salt having the formula wherein M is a Group I metal, a Group II metal, aluminum, tin, cobalt, lead, molybdenum, manganese, nickel or ammonium; each of R1 and R2 is a hydrocarbon-based radical; each of X1, X2, X3 and X4 is oxygen or sulfur; and each of a and b is 0 or 1.

28. A method according to claim 27 wherein M is zinc; each of R1 and R2 is a lower alkyl radical; X1 and X2 are oxygen; X3 and X4 are sulfur; and a and b are each 1.

29. A method according to claim 28 wherein the working comprises drawing.

30. A metal workpiece having an the surface thereof.
a film of a composition which provides lubricity thereto and which comprises at least one ester of an aliphatic polycar-boxylic acid having about 4-20 carbon atoms and a saturated aliphatic alcohol having at least about 10 carbon atoms, said composition melting within the range of about 35-70°C and said composition additionally containing at least one of a carboxy-lic acid or derivative thereof and a phosphorus acid salt having the formula wherein M is a Group I metal, a Group II metal, aluminum, tin, cobalt, lead, molybdenum, manganese, nickel or ammonium; each of R1 and R2 is a hydrocarbon-based radical; each of X1 and X2, X3 and X is oxygen or sulfur; and each of a and b is 0 or 1.

31. A metal workpiece having on the surface thereof a film of a composition which provides lubricity thereto and which comprises at least one ester of an aliphatic polycarboxy-lic acid having about 4-20 carbon atoms and a saturated ali-phatic alcohol having at least about 10 carbon atoms, said composition melting within the range of about 35-70°C and said composition additionally containing a carboxylic acid or derivative thereof.

32. A workpiece according to claim 31 wherein the carboxylic acid or derivative thereof is a substituted succinic acid in which the substituent is a hydrocarbon-based substi-tuent, or an anhydride or lithium salt thereof.

33. A workpiece according to claim 32 wherein the carboxylic acid or derivative thereof is tetrapropenyl succinic anhydride.

34. A metal workpiece having on the surface thereof a film of a composition which provides lubricity thereto and which comprises at least one ester of an aliphatic polycar-boxylic acid having about 4-20 carbon atoms and a saturated aliphatic alcohol having at least about 10 carbon atoms, said composition melting within the range of about 35-70°C and said composi tion additionally containing a phosphorus acid salt having the formula wherein M is a Group I metal, a Group II metal, aluminum, tin, cobalt, lead, molybdenum, manganese, nickel or ammonium; each of R1 and R2 is a hydrocarbon-based radical; each of X1, X2, X3 and X4 is oxygen or sulfur; and each of a and b is 0 or 1

35. A workpiece according to claim 34 wherein M is zinc; each of R1 and R2 is a lower alkyl radical; X1 and X2 are oxygen; X3 and X4 are sulfur; and a and b are each 1.

36. A workpiece according to claim 31 wherein the composition additionally contains a phosphorus acid salt having the formula wherein M is a Group I metal, a Group II metal, aluminum, tin, cobalt, lead molybdenum, manganese, nickel or ammonium; each of R1 and R2 is a hydrocarbon-based radical; each of X1, X2, X3 and X4 is oxyyen or sulfur; and each of a and b is 0 or 1.

37. A workpiece according to claim-wherein M is zinc; each of R1 and R2 is a lower alkyl radical; X1 and X2 are oxygen; X3 and X4 are sulfur; and a and b are each 1.