AU668409B2

AU668409B2 - Composition and use

Info

Publication number: AU668409B2
Application number: AU45769/93A
Authority: AU
Inventors: Bernard Tury
Original assignee: Imperial Chemical Industries Ltd
Current assignee: Imperial Chemical Industries Ltd
Priority date: 1992-08-07
Filing date: 1993-07-14
Publication date: 1996-05-02
Anticipated expiration: 2013-07-14
Also published as: EP0654073A1; GB9216776D0; JPH08500135A; GB9314512D0; ZA935349B; AU4576993A; KR950703046A; CA2141294A1; WO1994003564A1; BR9306849A

Description

h i 1 ii a ,A" OPI DATE 03/03/94 AOJP DATE 26/05/94 APPLN. ID 45769/93 PCT NUMBER PCT/GB93/01473 1111111 111111111111111111111111 11111111A9II111 AU9345769 INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (51) International Patent Classification 5 (11) International Publication Number: WO 94/03564 141/06, C23F 11/10 Al (43) International Publication Date: 17 February 1994 (17.02.94) (21) International Application Number: PCT/GB93/01473 (81) Designated States: AU, BR, CA, JP, KR, US, European patent (Al, BE, CH, DE, DK, ES, FR, GB, GR, IE, IT, (22) International Filing Date: 14 July 1993 (14.07.93) LU, MC, NL, PT, SE).

Priority data: Published 9216776.6 7 August 1992 (07.08.92) GB With international search report.

(71) Applicant (for all designated States except US): IMPERIAL CHEMICAL INDUSTRIES PLC [GB/GB]; Imperial Chemical House, Millbank, London SW1P 3JF (GB).

(72) Inventor; and Inventor/Applicant (for US only) TURY, Bernard [GB/ GB]; 8 Spring Vale, Prestwich, Manchester M25

(GB).

(74) Agents: DRAGGETT, Peter, Thornton et al.; ICI Group Patents Services Dept, P.O. Box 6, Shire Pai-. Bessemer Road, Welwyn Garden City, Hertfordshire AL7 1HD

(GB).

(54)Title: COMPOSITION AND USE (57) Abstract A composition comprising a hydroxyoxime together with the reaction product of an alkyl substituted cyclic anhydride and a hydrophilic compound containing hydroxyl and/or amino groups, a process which comprises treating at least part of the surface of a metal with the composition, a metal coated with the composition, and a lubricant composition comprising the composition and an oil or a grease. The reaction product of the alkyl cyclic anhydride may be the reaction product of polyisobutenyl succinic anhydride and ethanolamine. The hydroxyoxime may be 2-hydroxy-5-nonylbenzaldoxime or oneoxime. The composition may be used to inhibit corrosion of metals, particularly iron.

WO 94/03564 PCT/GB93/01473 COMPOSITION AND USE This invention relates to a new composition, and the use of such a composition to inhibit the corrosion of metals, especially when incorporated into oils and greases, and thus to a process which comprises treating least part of the surface of a metal with the composition, a metal coated with the composition, and a lubricant composition comprising the composition and an oil or a gree-e.

In our published European 'atent Application No 247728 there is disclosed a composition comprising an optionally substituted hydroxyoxime and an anhydride containing a long alkyl chain. The composition may be incorporated into an oil for the protection of metal surfaces against corrosion, and under most conditions, the composition provides extremely good protection of the metal surface against corrosion. However, when moisture is present the efficacy of the composition can be severely impaired, and the anti-corrosive properties imparted to the metal surface can be unacceptable.

The composition disclosed in EP 247728 can also be incorporated in to greases for the lubrication of metal surfaces which are in sliding or frictional contact. In most instances such grease formulations provide excellent antiwear characteristics on those metal surfaces. However- in the presence of moisture, the grease has been found to destructure under certain, circumstances and the lubricating characteristic of the grease is lost thus resulting in greater wear and/or corrosion of the metal surfaces.

We have now found that improved corrosion inhibition and greater resistance to moisture can be obtained using mixture of a hydroxyoxime compound together with the reaction product of a substituted cyclic anhydride and an organic moiety containing amino and/or hydroxyl groups.

WO 94/03564 PCT/GB93/01473 2 That such compositions have been found effective is surprising, since in most cases the individual components of the composition have been found to exhibit little, if any, anti-corrosion properties, when incorporated into to an oil and applied to a metal surface.

According to the present invention, there is provided a composition comprising a) a surface-active anhydride derivative of the general formula I X-Y-(Z)m (I) wherein X represents a saturated or unsaturated hydrocarbon group containing from 8 to 500 carbon atoms; Y represents a succinic anhydride residue or an aromatic anhydride residue carried terminally on the group X; each Z independently represents an organic group carrying an oxygen, sulphur or nitrogen atom through which it is linked to Y; m is 1 or 2; and b) a hydroxyoxime.

The group X is preferably a saturated or unsaturated aliphatic hydrocarbon chain which has a molecular weight of from about 100 to about 8000 and especially from about 100 to about 2000. Thus, the group X preferably contains at least 8 carbon atoms and up to about 150 carbon atoms and can be linear or branched.

Examples of such groups are nonyl, decyl, decenyl, dodecyl, dodecenyl, hexadecyl, octadecyl, octadecenyl and long alkyl chains such as those obtained for example by the polymerisation or copolymerisation of mono-olefins containing from 1 to 6 carbon atoms, for example, ethylene, propylene, but-1-ene, but-2-ene or isobutylene.

_U II---II WO 94/03564 PCT/GB93/01473 3 Preferred groups X are those derived from the polymerisation of isobutylene. These polymers can be made by standard methods and are commonly referred to as alk(en)yl polymers.

Such polymers have a terminal double bond that can be reacted with maleic anhydride to form alk(en)yl substituted succinic anhydride derivatives by reaction in the presence of a standard condensation catalyst for example a halogen such as bromine, to form a compound of formula II X CH

CH

2 0 0 0 and such compounds are those which are used in the compositions of EP 247728.

The alk(en)yl substituted succinic anhydrides of formula II are commercially readily available and can be used in the form in which they are available without further purification.

Polyisobutylene succinic anhydride is commonly referred to as

PIBSA.

A preferred compound of formula II, is a poly(isobutenyl)succinic anhydride-and particularly one with a number average molecular weight of up to 5000.

When the group Y is an aromatic anhydride residue, it is preferably derived from phthal ic anhydride, and especial ly phthal ic anhydride wherein the group X is attached in the 4-position relative to the anhydride group. It is preferred, however, that the group Y is a succinic anhydride residue derivable from the succinic anhydride group OIL.-- t-- WO 94/03564 PCT/GB93/01473 4 X CH CH 2 0 0 0 shown in formula II.

When Y is such a group trivalent group of the formula it is preferably a di- or CH CH 2 CO CO or CH CH 2 CO CO or CH CH 2 CO CO linking the group X to one or two groups Z.

The group Z in the compound of formula is preferably the residue of an organic compound containing at least one amino or hydroxyl or thiol group and containing up to carbons, more preferably up to 12 carbon atoms and especially up to 6 carbon atoms. The group Z is preferably an optionally substituted alkyl group, which may be linear or branched, but is preferably linear and preferably carries up to a total of 6 amino and/or hydroxyl groups, more preferably from 2 to 4 amino and/or hydroxyl groups, and especially 2 or 3 amino and/or hydroxyl groups. Where the group Z is I inked to Y through nitrogen amino this is preferably the nitrogen atom of an amino group which may be primary or secondary but is preferably a primary amino group. It is especially preferred that the organic group contains both an amino group and a hydroxyl group through either of which it may be joined to Y.

ON-. -I WO 94/03564 PCT/GB93/01473 5 The group Z may contain other groups in addition to the amino and/or hydroxyl and/or thiol groups such as carboxyl ic acid groups.

The group Z is pref.erably derived from an alcohol or a polyol for example it may be derived from ethylene glycol, propylene glycol, glycerol, trimethylolpropane, pentaerythritol or sorbitol.

The group Z may be derived from an amine or polyamine for example ethylenediamine, trimethylenediamine, hexamethylenediamine, tetraethylenepentarnine, dimethylaminopropylamine or diethylamino- propylamine.

However, the group Z is preferably derived from an organic compound containing both amino and hydroxyl groups such as monoethanolamine, diethanolamine, dipropanolamine, tris(hydroxymethyl)aminomethane or dimethylaminoethanol. The group Z may also be derived from an organic compound containing other groups such as a "carboxylic acid group in addition to the amino and/or hydroxyl group, for example glycine or glycollic acid.

In practice the compounds of formula are obtained as a mixture of isomers.

For example, those derived from polyisobutylene and maleic anhydride have the following major components:-

CH

3 c H C CH, 2

CH(COOH)-CH

2

-CO-Z

CH

3 n or -6-

CH

3 H C CH2 CH(CO-Z)-CH 2

-COOH

CH

3 -n wherein n has an approximate value of from 2 to 100 such that the compound has a molecular weight from about 200 to 5000 and Z is as hereinbefore defined and is linked to the CO group through an oxygen, nitrogen or sulphur atom.

The compounds of formula are readily prepared by reacting the S. appropriate alk(en)yl succinic anhydride with the appropriate organic amino or alcohol compound at a temperature of from 70 to 150 0 C in an inert solvent or o° 10 diluent, for example, xylene. Reaction is continued until a substantially constant acid value is achieved.

Preferably, the reagents are used in substantially equimolar proportions based on the anhydride ring and the hydroxyl and/or amino groups.

oe! Thus they produce a half derivative of the succinic group having a free S. 15 carboxylic acid group obtained by the opening of the anhydride ring, as shown in formulae III and IV.

Excess amounts of the organic moiety represented by Z may be used to react with the alk(en)yl anhydride such that the surface active anhydride derivative of general formula I contains no free carboxylic acid groups.

However, it is preferred that the compound of general formula I contains one free carboxylic acid group, and it is especially preferred that m is 1.

SC C:\WINWORD\SIMONE\NODELETE\45769C93.DOC C~ f -I ~I WO 94/03564 PCT/GB93/01473 7 The preferred anhydrides are succinic anhydrides where the group X is an isobutylene polymer of molecular weight from about 100 to 8000, and especially from 600 to 6000 and more especially from 800 to 1200.

A preferred example of the compounds of general formula I is the reaction product of polyisobutenyl succinic anhydride having a molecular weight of approximately 1100 and ethanolamine.

The hydroxyoxime which is component of the composition in accordance with the present invention is preferably an aromatic hydroxyoxime of the formula

N-OH

A R wherein A is an aromatic system, especially a benzene ring; and R I is a hydrogen atom or a substituted or unsubst'tuted hydrocarbon group. The hydroxyoxime is more preferably a hydroxy monooxime of the formula Vi or hydroxy bi-oxime of formula OH OH NOH NOH 1 HON\ R

V

R

2 R 2 wherein R 1 is as hereinbefore defined; and

R

2 is a substituted or unsubstituted Cs-22 hydrocarbon group.

WO 94/03564 PCT/GB93/01473 8 The group RI is preferably hydrogen but may be an alkyi, aryl or benzyl group, which may be substituted. When R' is aryl, it is preferably phenyl and when R' is alkyl, it is preferably CI- 4 alkyl, for example methyl.

In the bis-oxime compound of formula VI, the second oxime group is preferably in the 6-position (ie ortho to the hydroxyl group) and especially preferred compounds of this type are the 2,6-bis(oximinomethyl)-4-alkylphenols.

The group R 2 is preferably a Cs-14 alkyl group which may be linear or branched and may be saturated or unsaturated, but is preferably saturated. The group R 2 is preferably in the para position with respect to the phenolic hydroxyl group when the compound is a 2-hydroxy-5-alkylbenzaldoxime or Examples of the group R 2 include decyl, decenyl dodecyl, dodecenyl, hexadecyl, octadecenyl and especially nonyl Specific examples of the hydroxyoxime compounds are and phenoneoxime.

The weight ratio of the surface active anhydride derivative of general formula I to the hydroxyoxime may be between 99:1 to 1:99 but will generally be from 10:1 to 1:10, i particularly from 5:1 to 1:5. However, the .preferred proportions will be dependent on the particular compounds present in the mixture.

The compositions of the present invention provide improved corrosion inhibition in corrodible metals and certain of the compositions also provide improved anti-wear properties and/or improved anti-oxidation properties.

Thus, as a further aspect of the present invention, there is provided a process which comprises treating at least part of the surface of a metal with a composition comprising a surface active anhydride derivative of general formula I, and ii WO 94/03564 PCT/GB93/01473 -9a hydroxyoxime, as hereinbefore defined.

The process of the present invention is especially suitable for the corrosion inhibition of iron, zinc, copper, tin and aluminium and in particular mild steel and the zinc surface of galvanised steel.

The metal may be treated directly with the composition.

However it is generally preferred to apply the composition to the metal surface in the form of a solution in a suitable organic liquid or as an aqueous emulsion or dispersion of the composition or as an aqueous emulsion of a solution of the composition in an organic liquid.

The composition may be used to provide a protective coating in its own right, or as a metal pre-treatment before the application of a surface coating, or may be incorporated into a surface coating composition, "or may be employed as an additive to refined petroleum products such as lubricating oils, turbine oils, fuel oils, gasohols and greases.

Any suitable organic liquid may be used as a solvent for the composition, such as aliphatic and aromatic hydrocarbons, and their halogenated derivatives, ethers and ketones.

Especial ly preferred solvents are those having good wetting and drying properties and include for example benzene, toluene, xylene, kerosene, white spirit, chloroform, and 1,1,1-trichloroethane.

Aqueous emulsions of the composition may be formed in conventional manner using conventional dispersants and surfactants, including non-ionic dispersants.

It may be convenient to treat the metal with an aqueous emulsion of the composition, particularly if the anhydride present in the composition is a liquid which can be formed directly into an emulsion.

L WO 94/03564 PCT/GB93/01473 10 The process of the present invention may provide corrosion inhibition either without the application of a further surface coating or as a pre-treatment before the application of a further surface coating. Thus, the treatment may be used for example as a temporary protection of a metal, for example while the metal is being transferred from one site to another and the protective coating subsequently removed i before or during further processing.

Alternatively, the composition may be formulated in a surface coating composition, for example a paint (primer) such S as air-drying, oi I-modified system or a system including a chlorinated rubber, lacquer, resin or other protective coating.

The surface coating may be a solvent-based composition, for example a cellulose/solvent based primer paint such as those used for car "touch up" paints.

The components of the composition are soluble in j solvents generally used for such primers (for example nitrocellulose) and may be incorporated directly. The composition may also be used as an emulsion in aqueous I emulsion surface coating systems, for example primers or j protective coatings based on polymer latices such as for example acrylic and st"rene/aerylic latices and vinyl acrylic co-polymer latices including acrylate modified vinyi chloride vinylidene chloride copolymer latices.

The composition may also for example be incorporated in temporary alkali-removable protective coatings (whether solvent-based or emulsion based) of the addition polymer type in which the polymer contains carboxyl groups.

The composition or the solution or emulsion thereof may be applied to the metal in conventional manner, for example by dipping, spraying or brushing. The temperature of the application may be from 0 to i Ui c' ~i WO 94/03564 PCT/GB93/01473 11 Typically, solutions of the composition may contain from 0.1 to 20% by weight of the mixture of the anhydride derivative and the hydroxyoxime, whilst emulsions preferably contain from 0.1 to 5% by. weight of the mixture of anhydride derivative and hydroxyoxime.

The presence of from 0.1 to 2% by weight of the mixture of anhydride derivative and hydroxyoxime in a surface coating emuls.on formulation is generally sufficient to provide improved corrosion inhibition.

If the composition contains materials in addition to the anhydride derivative and the hydroxyoxime, the amount of the composition which is used should be sufficient to provide the mixture of the anhydride derivative and the hydroxyoxime in the proportions as set out herein.

The metal to be treated may be brightly polished and/or freshly cleaned, but it is an advantageous feature of the i process of the present invention that effectiv-e corrosion Sinhibition may be obtained even on a lightly rusted surface.

Indeed we have found that better results are in general achieved when a surface is treated in an "as received" condition than when that same surface is freshly cleaned or brightly polished.

The present composition has been found to giv. greatly improved protection of metal surface against wear and j 25 corrosion in tank oil systems and greases which are subject to contact with water.

Thus, according to a further aspect of the present invention there is provided a lubricant composition comprising a) a surface active anhydride derivative of the formula I X-Y-(Z)m (I) wherein X, Y, Z and m are as hereinbefore defined; b) a hydroxyoxime; and c) an oil or a grease; i. 9 WO 94/03564 PCT/GB93/01473 12 The oil is preferably a mineral oil or a synthetic oil such as a polyalkylene glycol, a polyalpha olefin, an ester and in particular a phthalate, a perfluoroalkyl ether or a silicone.

The greases are preferably mineral or synthetic oils which have been thickened by the addition of gelling agents.

Typically, the mineral oil is a hydrocarbon oil, and the synthetic oil may be for example a synthetic hydrocarbon oil, a diester such as di(2-ethylhexyl)sebacate, a perfluoroalkyl ether or a silicone oil.

Many greases are obtained using soaps as the gel I ing agent, especially lithium soaps. However, non-soap gell ing agents can produce a grease having improved properties, especially the clarity to remain effective at higher use temperatures. Examples of non-soap gelling agents present in such greases are clays, carbon black, silica and polyurea all of which are preferably incorporated into the oil as finely divided solid materials.

Finely divided clay particles, for example clays of the bentonite or hectorite types can be used as non-soap gelling agents to obtain a grease from a mineral oil. Preferably, the clay particles are surface-coated with an organic material such as a quaternary ammonium compound.

Where the grease is based on a silicone oil, the non-soap gelling agent is preferably si ica, and especially fused silica having an average particle size less than one micron.

The lubricant composition preferably contains from 0.1 to 30% by weight of the hydroxyoxime relative to the total volume thereof and more preferably from 0.1 to In addition to the hydroxyoxime and anhydride derivative, the lubricant composition may include various other ingredients commonly incorporated into such compositions such as oxidation inhibitors, and extreme pressure additives.

I

F

L WO 94/03564 PCT/GB93/0 1473 13- The lubricant composition may be prepared using any of the techniques which are effective for incorporating additives into oil or grease media.

For example a grease composition may be formed by stirring together the thickened grease with a composition containing the anhydride derivative and the hydroxyoxime.

As an alternative, the composition of the anhydride derivative and the hydroxyoxime may be incorporated into an oil which is subsequently thickened to form a grease.

The lubricant composition in which component is a grease may be used in any application for which a grease is known, and in particular can be used in general automotive applications and also in bearings including high performance bearings.

We have found that when subjected to an anti-rust test the present lubricant composition shown improved resistance to corrosion and destructuring compared to a grease containing the composition disclosed in EP 247728.

A bearing containing, a lubricant composition in accordance with the present invention is a further feature of the present invention.

The compositions of the invention may also include other materials, particularly materials which also provide corrosion inhibiting properties. Such corrosion inhibiting materials include, for example, petroleum sulphonates, aryl sulphonates and the metal salts thereof.

The other materials may be present in the composition in a substantial proportion of up to several times, for example up to ten times, by weight of the composition of the anhydride and the hydroxyoxime.

CZ|

.r WO 94/03564 PCT/GB93/01473 14 In general no particular advantage is achieved by using a large excess of the other materials and preferably the proportion of the other materials do not exceed twice the weight of the composition and conveniently the other materials are present in essentially an equal proportion by weight relative to the weight of the composition.

Various aspects of the present invention are set out in more detail hereafter in the following i I llustrative examples in which al I parts and percentages are by weight unless otherwise stated.

Example i Samples of a solvent-neutral mineral oil containing 0.1% corrosion inhibitor and a sample of the sample oil containing no additive were subjected to an oil/water corrosion test based on ASTMD 665B modified as set out hereafter.

The test involves stirring a mixture of the oil (300 ml.) and synthetic sea water (30 ml.) for 24 hours at 1000 rpm and at a temperature of 60"C containing a completely i immersed and previously weighed cyl indrical steel specimen.

The metal specimen is then removed, cleaned, re-weighed to determine weight loss (if any) and examined for evidence of corrosion.

The results obtained are set out in Table One.

~II~

WO 94/03564 PCT/GB93/01473 TABLE ONE I Example or I Additive I Wt. loss 1 Visual I Comp Ex I I (mg) I Appearance I I I I I I S1 I 10.05% BAO I I 0.05% PMEAI I 0.2 1 Rust free I I A I 1% BAO I 113 1 Corroded I 1 B I 0.1% PMEA 1 60 I Corroded I S C I Nil I 106 I Corroded I I_ I I I Notes to Table One BAO is PMEA is a reaction product of polyisobutenylsuccinic anhydride of approximate -molecular wei-ght 1100 and monoethanolamine.

Example 2 Samples of a lithium complex grease containing 2% corrosion inhibitor and also a sample of the same grease containing no additive were subjected to a modified ASTM D1831 (Roll Stabi l ity of lubricating grease) test as described hereinafter.

A sample of lithium complex grease (90 parts) containing 2% corrosion inhibitor and distilled water (10 parts) were placed in a test cylinder.

The grease was distributed evenly over the inside wall of the cylinder, a weighted roll was placed in the cylinder and the cap tightened. The cylinder was then rolled at 165 15 rpm for two hours after which the grease removed and subjected to the cone penetration test for lubricating greases.

i i i" li I I• I I 1 l I I I I I i WO 94/03564 PCT/GB93/01473 16- This was carried out using one-half scale cone equipment and the procedure of ASTM D1403. The cone penetrations were carried out on samples of grease which had been brought to and subjected to sixty double strokes in a grease worker in the manner described in ASTM D1403. Using the standard formula as set out in ASTM D1403, the measurements made were transformed to give the work penetration of the cone for full scale cone equipment.

The results obtained are set out in Table Two.

TABLE TWO I Example or I Additive I Worked I Comp. Ex I I Penetration I I I I I 2 1 1.5% BAO I I I 0.5% PMEA 1 311 S D I 1.5% BAO 1 1 I 0.5% TPSA I destructured I IE I Nil I 300 Notes to Tab I e Two BAO is 2-hydroxy-5-nony I benza I doxime PMEA is a reaction product of polyisobutenyIsuccinic anhydride of approximate molecular weight 1100 and monoethano amine TPSA is tetrapropenylsuccinic anhydride.

measured in tenths of a millimetre.

Claims

1. A compos i t i on I'nck a) a surface-active anhydride derivative of the general formula I X-Y-(Z)m I wherein X represents a saturated or unsaturated hydrocarbon chain containing from 8 to 500 carbon atoms; Y represents a succinic anhydride residue or an aromatic anhydride residue carried terminally on the group X; each Z independently represents an organic group carrying an oxygen, sulphur or nitrogen atom through which it is linked to Y; and m 1 or 2, and b) a hydroxyoxime.

2. A composition as claimed in claim 1 %h-erein m is 1, and Y represents a succinic anhydride residue.

3. A composition as claimed in claim 1 wherein the anhydride derivative is one in which X is nonyl, decyl decenyl, dodecyl dodecenyl, hexadecyl, octadecyl or oct&decenyl, or in which X is derived from an isobutylene polymer made from but-l-ene, but-2-ene or isobutene and having a molecular weight from about 800 to 2000.

4. A composition as claimed in claim I wherein the group Z is derived from ethylene glycol, propylene glycol, glycerol, trimethylolpropane, pentaerythritol, sorbitol, ethylene- diamine, trimethylenediamine, hexamethylenediamine, tetraethylenepentamine. dimethylaminopropylamine, diethylaminopropylamine, etha7:o am i ne, diethanolamine, Omm C -;rrrsa.a WO 94/03564 PCT/GB93/01473 18 dipropanolamine, tris(hydroxymethy )aminoethane or dimethyl- aminoethanol. A composition as .claimed in claim 1 wherein the anhydride derivative is a complex mixture of isomers having as major components H CH, I C CH 3 CH 2 CH(COOH)-CH 2 -CO-Z H CHS C CH, CH 3 n CH(CO-Z)-CH 2 -COOH wherein L n n has an approximate value of from 2 to 100 such that the compound has a molecular weight from about 200 to 5000; and Z is a straight or branched alkyl group carrying hydroxyl, amino and/or carboxylic acid substituents, the alkyl group being bonded to the CO group through the residue of a hydroxyl or amino group.

6. A composition as claimed in claim 1 which contains a hydroxyoxime of general formula )-OH cR WO 94/03564 PCT/GB93/01473 19 wherein A is an aromatic system; and R 1 is a hydrogen atom or a substituted or unsubstituted hydrocarbon group.

7. A composition as claimed in claim 6 wherein the hydroxyoxime is 2-hydroxy-5-nonylbenzaldoxime or 2 -hydroxy-5-nonylacetophenone oxime.

8. A process which i'rc-ole.s treating at least part of the surface of a metal with a composition as claimed in any one of claims 1 to 7.

9. A metal at least part of one surface of which has been coated with a composition as claimed in any one of claims 1 to 7. A lubricant composition inc\uAk, a) a surface-active anhydride derivative of the general formula I I wherein X represents a saturated or unsaturated hydrocarbon chain containing from 8 to 500 carbon atoms; Y represents a succinic anhydride residue or an aromatic anhydride residue carried terminally on the group X; each Z independently represents an organic group carrying an oxygen, sulphur or nitrogen atom through which it is linked to Y; an 4 m is 1 or 2, b) a hydroxyoxime; and c) an oil or a grease. 3 5. O i i. .r -e I _1IL -L I~L~ilm~? INTERNATIONAL SEARCH REPORT Inter. al Application No PCT/GB 93/01473 A. CLASSIFICATION OF SUBJECT MATTER IPC 5 C10M141/06 C23F11/10 According to International Patent Classification (IPC) or to both national classification and IPC B. FIELDS SEARCHED Minimum documentation searched (classification system followed by classification symbols) IPC 5 C10M C23F Documentation searched other than minimum documentation to the extent that such documents are included in the fields searched Electronic data base consulted during the international search (name of data base and, where practical, search terms used) C. DOCUMENTS CONSIDERED TO BE RELEVANT Category Citation of document, with indication, where appropriate, of the relevant passages Relevant to claim No. A EP,A,O 247 728 (IMPERIAL CHEMICAL 1-3,6-10 INDUSTRIES) 2 December 1987 cited in the application see page 1, line 42 page 5, line 13; claims 1-5,7-14 A EP,A,0 208 560 (EXXON CHEMICAL PATENTS 1-4,8-10 INC.) 14 January 1987 see page 4, line 1 page 13, line 34; claims 1,4-11,17-22; example 11 A US,A,3 331 776 KRUKZIENER) 18 July 1-4,8-10 1967 see the whole document Further documents are listed in the continuation of box C. Patent family members ar listed in annex. Special categories of cited documents later document published after the international filing date document defining the general state of the art whi. not or priority date and not in conflict with the application but considered to be of particular relevance cited to mdrstand the principle or theory underlying the invention earlier document but published on or after the international te c d filing date X' document of particular relevance; the claimed invention filig de cannot be considered novel or cannot be considered to "L document which may throw doubts on priority clairs) or involve an inventive step when the document is taken alone which is cited to establish the publication date of another docxmen of particular relevance; the claimed invention citation or other special reason (as specified) Y" document of particular relevance; the claimed invention citation or other special reason (as specified) cannot be considered to involve an inventive step when the document referring to an oral disclosure, use, exhibition or document is combined with one or more other such docu- other means ments, such combination being obvious to a person skilled document published prior to the international filing date but in the art. later than the priority date claimed document member of the same patent family Date of the actual completion of the international search Date of maihng of the international search report 2 November 1993 18. 93 Name and mailing address of the ISA Authorized officer European Patent Office, P.B. 5818 Patentlaan 2 NL 2280 HV Rijswijk Tel. (+31-70) 340-2040, Tx. 31 651 epo B, Id, Fax: (+31-70) 340-3016 BLASBAND, I Form PCT/ISA/310 (second sheet) (July 1993)

016.. I .41 INTERNATIONAL SEARCH REPORT -dtorrnaton on patent family members Inter. mal Appcation No PCT/GB 93/0 1473 Patent document Publication IPatent family I Publication cited in search report dame member(s) I date EP-A-0247728 02-12-87 JP-A- 62290887 17-12-87 US-A- 4865647 12-09-89 EP-A-0208560 14-01-87 AU-B- 602125 04-10-90 AU-A- 6002686 15-01-87 CA-A- 1262721 07-11-89 DE-A- 3687550 04-03-93 JP-A- 62015296 23-01-87 US-A- 5118432 02-06-92 US-A-3331776 BE-A- 638130 DE-B- 1250583 FR-A- 1370420 GB-A- 981850 NL-C- 134315 NL-A- 283936 A ~'r.PCT/ISA/210 (patent family annex) (July 1992)