JPS63304095A - Low phosphorus and zinc lubricant - Google Patents

Abstract

Lubricants having antiwear, corrosion inhibition and antioxidant performance appropriate to modern oil requirements with reduced or zero amounts of zinc and phosphorous and without the need for large amounts and/or expensive forms of antioxidant comprise 5 to 500 parts per million by weight (ppm) of added copper present in oil-soluble form, one or more added oil-soluble sulphur-containing compounds and a bearing corrosion inhibitor.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to lubricating compositions containing low or no phosphorus and zinc content, particularly automotive crankcase lubricants.

PRIOR ART - There is a desire to reduce the amount of phosphorus in lubricants due to its deleterious effects, and phosphorus is commonly used in catalysts in catalytic converters for emission control. . The phosphorus concentration is typically 0.
Although it used to be about 1%, it has gradually become necessary to reduce 784 degrees to 0.05% by weight or less, or to completely remove it. However, zinc dialkyldithiophosphates (ZDDPs) and other phosphorus-containing additives are widely used as antiwear and/or antioxidant additives, and simply reducing or eliminating these components results in lower engine It becomes a characteristic lubricant.

The present invention provides lubricating compositions and concentrates containing low or no amounts of phosphorus and zinc, which contain sulfur, copper and bearing corrosion inhibitors, and which provide significant engine corrosion protection. It was found that it gives performance.

U.S. Pat. No. 2,356,661 contains 50 to 1,000 ppm of copper as an oil-soluble organic compound, such as copper dialkyldithiocarbamate, and 0.00 ppm of total sulfur in the oil.
We are dealing with lubricating oils containing 1 to 065% by weight of phosphorus-containing compounds, where the sulfur is provided as oil-soluble sulfur compounds such as thiocarbamates.

U.S. Pat. No. 2,343,756 discloses adding copper compounds containing phosphorus-containing copper complexes to lubricating oils along with sulfur compounds. The amount of sulfur disclosed herein is from 0.1 to
The amount of sulfur is 0.5% by weight, and it is said that if sulfur exceeds 0.5% by weight, it may be harmful.

In US Pat. No. 2,552,580, cuprous thiophosphate is included in relatively high concentrations in lubricating compositions to provide high phosphorus concentrations in the kernel oil. In U.S. Pat. No. 3,346,493, various metal-containing polymeric amine-metal reagents are used as detergents in lubricating compositions. - In the example, the lubricant is described as containing inter alia a copper salt of an acrylated nitrogen compound, 0.075% phosphorus as ZDDP reacted with hexene oxide, and sulfurized methyl ester of tall oil acid.

Other copper-containing lubricants contain more phosphorus or no sulfur at all. U.S. Patent No. 4.122
．． No. 033 discloses a whole group of transition metal compounds as antioxidant stabilizers for use with amines, selenides, phosphines or phosphites in a variety of applications including as lubricant additives. He says it can be done. None of the above documents discloses a fully formulated lubricant that fully satisfies the requirements for modern lubricants, and none of them while maintaining wear resistance, anti-oxidation and anti-corrosion properties. , not specifically intended to reduce phosphorus concentrations.

European Patent No. 24.146 discloses a lubricant composition comprising an ashless dispersant and/or a polymeric viscosity index improving dispersant and copper, which may be in the form of a dithiocarbamate; Requires the presence of .01-0.5% by weight zinc and 0.01-0.5% by weight phosphorus. Thiadiazole polysulfide is an optional component.

U.S. Pat. No. 4,330,420 uses a mixture of dialkyldiphenylamine and sulfurized polyolefin to
To compensate for the reduced amount of DDP, an oil is disclosed that has a reduced phosphorus content (but only slightly O, OS% P).

The answer does not mention the use of copper or thiadiazole polysulfide.

European Patent No. 89,844 discloses that 4,4'-methylene-(
2,6-di-t-butylphenol) and tri-5e
c C* +t Reaction product with alkyl orthoboric acid ester and its use in lubricants, 0.05 to 0
．． It is disclosed that the amount of ZDDP can be reduced to 11% P by weight.

U.S. Pat. No. 4,490,265 describes boric acid-containing heterocyclic compounds (which may be in the form of metal salts, including i! salts), thiadiazole polysulfides, terephthalic acid and bis(dithiobenzyl) metal derivatives as antioxidants. The present invention discloses lubricating oils containing bishindered phenols (wherein the metal may especially be copper) or sulfur-crosslinked bishindered phenols. There is no mention of the desirability of reducing or eliminating phosphorus, and all lubricant examples are
．． Contains 0.5% by weight of P. U.S. Patent No. 4,623
, 474 contains similar disclosure. U.S. Patent No. 4,
No. 627,930 also discloses boron-containing heterocyclic compounds which may be copper salts and may be sulfurized. Thiadiazole polysulfides and copper carboxylates have also been described. Although these boron-containing heterocycles are described as phosphorus-free, there is no disclosure of the oil as a complete formulation containing less than 0.05% P by weight, U.S. Pat. No. 4.629, No. 580 contains similar information. U.S. Pat. No. 4,629.579 describes extreme pressure additives for lubricating oils and compositions, including those without ZDDP, boron and Metal-boron derivatives are disclosed.

However, compositions are disclosed that contain little or no phosphorus, along with sulfur and copper.

Lubricating compositions containing low or no phosphorus and no copper are disclosed in International Application No. 8,604.
, No. 601, No. 8,604,602 and No. 8,
No. 606,092.

SUMMARY OF THE INVENTION The present invention provides an antioxidant solution suitable for modern oils with low or no zinc and phosphorus content requirements and without the need for large amounts and/or expensive forms of antioxidants. The present invention provides a lubricant with anti-wear, anti-corrosion and anti-oxidation properties.

SUMMARY OF THE INVENTION The term "modern oil" as used in the present invention in connection with automotive crankcase lubricants refers to oils that can meet the general requirements for crankcase lubricants in major industrialized countries. shall mean. High performance engines, longer lifespans resulting in longer periods between oil changes, and higher operating temperatures all contribute to the high performance required of lubricating oils. The present invention relates specifically to automotive lubricants, which are classified under the SF API Engine Service Category (Engine 5service C) for service station oils.
APIS at the request and/or cooperation of
It is possible to meet and exceed the CD requirements of the CD/API engine service category for commercial oils (Coms+ercial oils: diesel engines) set by SAE and ASTM.

- In an aspect, the present invention provides a large amount of lubricating oil, from 5 to 500 pp.
m (weight it) of added copper present as oil-soluble, such that the composition preferably has a total sulfur content of 0.5 to 2.0% by weight, more preferably 0.5 to 1.0% by weight. one or more oil-soluble sulfur-containing compounds added to the sulfur-containing compound, and an effective amount of a bearing corrosion inhibitor, containing less than 0.05% phosphorus and 0.01% zinc by weight, preferably substantially substantially phosphorous-free. To provide a lubricating composition that does not contain zinc and does not contain zinc.

In a particularly preferred embodiment B of the present invention, the lubricating composition further comprises one or more ashless dispersants and/or one or more viscosity index improving dispersants and/or a high base which functions as an acid and rust inhibitor. Also includes one or more overbased additives such as calcium or magnesium sulfonates or phenates.

The use of copper in the present invention makes it possible to obtain low phosphorus oils with performance that meets modern oil requirements economically and with good oxidation control. This oxidation is catalyzed by metals that accumulate in the cedar oil due to wear or corrosion in automobile engines, with iron being a particular oxidation catalyst. At unreasonably low concentrations of copper, antioxidant activity may be insufficient in some applications. Under extremely high copper concentrations, the ash content of the oil is high and a high tendency for bearing corrosion is observed. The amount of copper added in this composition is generally 10
~400 ppm, typically 10-300, ppl %
Preferably 10-200 ppm, for example 60-! OO
It is ppm.

The antioxidant and anti-wear properties of the compositions of the invention, which contain small amounts of oil-soluble copper compounds and very little or no phosphorous, are surprising, and are sufficient to meet the rigorous demands of modern engine tests. . European patent no. 24
．． No. 146 teaches the presence of at least 0.01% by weight each of phosphorus and zinc.

It is also surprising that it works effectively in compositions containing zinc and other metal compounds, such as calcium or magnesium highly basic additives, which have inherent oxidizing activity.

In the present invention, the copper compounds used as antioxidants are those described in European Patent No. 24.146 as suitable for lubricants (provided that these copper compounds do not substantially contain phosphorus). ) can be selected.

Thus, copper can be incorporated into the oil as an oil-soluble copper salt of a synthetic or natural carboxylic acid. Examples of suitable carboxylic acids are fatty acids with 10 to 18 carbon atoms, such as stearic acid or palmitic acid; unsaturated acids, such as oleic acid; branched carboxylic acids, such as naphthenic acid, neodecanoic acid or 2-ethyl molecule 11t of 200 to 500 hexanoic acid; and alkyl- or alkenyl-substituted dicarboxylic acids, such as polyalkene-substituted succinic acids (such as octadecenylsuccinic acid, dodecenylsuccinic acid, and polyisobutinsuccinic acid).

Copper has the general formula: (RR'NCSS)nCu (where n is 1 or 2, R and R' are the same or different,
It can be incorporated into cedar oil as an oil-soluble copper dithiocarbamate having hydrocarbyl groups having 1 to 18 carbon atoms, preferably 2 to 12 carbon atoms, such as alkyl, alkenyl, aryl, aralkyl, alkaryl, and cycloalkyl groups. Other copper and sulfur containing compounds such as copper mercaptides, disulfides and thioxanthates are suitable for use in the present invention. Copper sulfonates, phenolates and acetylacetonates can also be used.

Copper can also be introduced as oil-insoluble in cedar oil, as long as it is present as an oil-soluble compound in the final lubricant composition. “Added copper
The term r)'' is intended to remove copper that is present in the oil as a result of copper buildup in the oil during use, for example due to abrasion or corrosion of copper-containing components.

The lubricating compositions of the present invention contain added oil-soluble sulfur compounds.

One preferred group of such sulfur compounds are dithiocarbamates [, preferably of the formula: (RR'NNC55)n
(However, R, R' and n are as defined above,
M represents a suitable metal, such as molybdenum or (as above) copper or an optionally substituted hydrocarbyl group. Preferred dithiocarbamates are dialkyldithiocarbamates, preferably having 2 to 12 carbon atoms, such as cyamyldithiocarbamates.

Sulfur can also be used in sulfurized unsaturated organic compounds, including mercaptides, especially mercaptides of aliphatic mercaptans (including copper mercaptides, as discussed above), sulfurized olefins (e.g., U.S. Pat. No. 4,119,549; ,119
, No. 550, No. 4,191,659 and No. 4,
147,640), sulfurized Diels-Alder addition products (e.g., U.S. Pat. No. 3,632,566;
No. 3,498,915 and US-E-No. 27.3
31) and in particular sulfurized unsaturated alcohols and esters, such as pine kola whale oil substitutes, sulfides including di- and polysulfides, thioethers, thiophenols, thioxanthates (as mentioned above (copper thioxanthates) ), sulfurized esters, thioesters, thioamides, thiazoles, such as benzothiazoles and especially mercaptobenzothiazoles, and thiadiazoles.

Inorganic lubricating oils contain sulfur, whereas synthetic oils can be sulfur-free, and therefore the amount of sulfur added as a sulfur-containing compound depends on the sulfur content of the base stock and other components in the lubricating composition. and change.

The lubricating compositions of the present invention advantageously have a sulfur content of 0.5 to 1.0% by weight total S, and Most preferably 0.1-0.5% by weight S is included as an oil-soluble added sulfur-containing compound (preferably as a sulfurized ester).

Bearing corrosion inhibitors are effective corrosion inhibitors for inhibiting corrosive effects on bearings, such as Cu/Pb bearings, where they can suffer from effects such as copper contamination and high weight loss. Such additives have been found to enhance the antiwear performance of this oil. Preferred bearing corrosion inhibitors are borates such as B(OR)+, (RO)
! B OB (OR) t or (ROBO)i,
(RO) JOR' OB (OR) z and mixtures thereof (provided that R is a substituted or unsubstituted alkyl, aryl or aralkyl group, or two R's together form a substituted or unsubstituted alkylene group) , R1 is a substituted or unsubstituted alkylene group), and these substances include, for example, alcohols (e.g. alkoxyalkanols: both short-chain alkanols and long-chain alcohols as in U.S. Pat. No. 4,440,656). and polyether alkanols); mono-, di- and trihydroxy alkanols (e.g. 2-ethylhexanol, 2-ethylhexane-1,3-diol,
Butane-1,2-diol, butane-1,3-diol, glycerol and the cycloaliphatic polyols described in U.S. Pat. No. 2,866,811; hydroxy esters (e.g. glyceryl monooleate); e.g. oleic acid and tris(hydroxymethyl)-aminomethane; sulfur-containing alcohols, such as those obtainable by reaction of epoxides with mercaptans, e.g. t-dodecyl-mercaptoethanol; alkanolamines, e.g. Amino alcohols such as triethanolamine and tri-isopropanolamine, hydroxyamines obtained by reaction of -grade amines (e.g. oleylamine) or secondary amines with ethylene or propylene oxide and U.S. Pat. No. 4,406,802 ml can be obtained from the compounds described in . The preferred alcohol is 2-methylpentane-1,3
-diols, butane-1,2-diol, butane-1.3-diol and similar 1,2- and 1,3-diols, as well as ethoxyethanol.

In one preferred aspect, the invention comprises from 0.01 to 10% by weight, preferably from 0.1 to 5% by weight of boric acid esters, especially esters of alkoxyalkanols or polyether alkanols, such as tris(ethoxyethyl)orthoborate or meth Includes borate esters or diborate esters of diols such as butane-1,3-diol.

In addition, bearing corrosion inhibitors include thiadiazole mercaptan,
In particular, thiadiazole polysulfides having 5 to 50 carbon atoms, derivatives or polymers thereof. Preferred substances are derivatives of 1.3.4-thiadiazole polysulfide,
For example, U.S. Pat. No. 2,719.125, U.S. Pat.
No. 9.126 and No. 3.087,932. Particularly preferred is 2,5-bis(t-octadithio)-1,3,4-thiadiazole (
Amoco 150) or 2,5-bis(nonyldithio)-
1,3°4-thiadiazole (Amoco)
158). Other similarly suitable materials are U.S. Patent No. 3.821.23.
No. 6, No. 3.904.537, No. 4.097.3
No. 87, No. 4, No. 107.059, No. 4.136.
No. 043, No. 4.188, 299 and No. 4.1
No. 93.882. Derivatives of thiadiazole mercaptans, such as esters, condensation products with halogenated carboxylic acids, aldehydes and amines, reaction products with alcohols or mercaptans,
Amine salts, dithiocarbamates, reaction products with ashless dispersants (see, for example, U.S. Pat. No. 4,140,643 and U.S. Pat. No. 4,136,043) and reaction products with halogenated sulfur and olefins, etc. can also be used.

These substances are preferably 0.01% based on the lubricating composition.
It is present in an amount of -10% by weight, more preferably 0.1-5.0% by weight.

The lubricating composition contains a small amount, i.e. less than 0.05% by weight,
Preferably less than 0.01% by weight, more preferably 0.0%
Although the lubricating composition may contain 0.5% by weight unsaturated phosphorus, more preferably the lubricating composition is substantially free of phosphorus.

In a preferred aspect, the lubricating composition of the present invention further comprises the following ingredients.

(A) 1 to 10% by weight of a naturally dispersible compound, which is an ashless nitrogen- or ester-containing dispersible compound, preferably (i) a long-chain hydrocarbon-substituted mono- and dicarboxylic acid or anhydride thereof; oil-soluble salts, amides, imides, oxazolines and esters or mixtures thereof; (ii) long chain aliphatic hydrocarbons having directly attached polyamines; and (iii) 1 mole of long chain hydrocarbon substituted phenols; ~2.5 mol formaldehyde and 0.5-2
A Mannich condensation product formed by condensing these in a ratio of molar polyalkylene polyamines, provided that the long chain hydrocarbon groups are Ct-C, a monoolefin polymer, and the polymer has a molecular weight of 700 to 5.000. It is a compound selected from; and/or (B) 0.
3-10% by weight nitrogen or ester containing polymeric viscosity index improving dispersant. This includes:

(a) Polymers of C4-C24 unsaturated esterophores of vinyl alcohol or C1-C3° unsaturated mono- or dicarboxylic acids and unsaturated nitrogen-containing mono-monocarbons having 4 to 20 carbon atoms; (b) Amines, hydroxylamines (C) a polymer of ethylene and a C3-Coo olefin, further neutralized with C1-C2o unsaturated nitrogen; The nitrogen-containing dispersant additive is a crankcase morph It is known in the art as a sludge dispersant for oils. For example, U.S. Pat. No. 3,275,55
No. 4, No. 3,565.804, No. 3, 442.8
No. 08, British Patent No. 983.040 and BE-A No. 658,236.

The most commonly used dispersants are alkenylsuccinic anhydrides, such as polyisobutenylsuccinic anhydride, and U.S. Pat.
No. 3.172.892, No. 3.624.19
No. 5, No. 3,024,237, No. 3,219,6
No. 66, No. 3.216,936 and BE-A No. 6
No. 62.875.

In addition, the ashless dispersant is a long-chain hydrocarbon-substituted carboxylic acid,
Esters derived from hydroxy compounds such as -hydric and polyhydric alcohols or aromatic compounds such as phenols and naphthols may also be used, preferably see for example US Pat. No. 3,522,179.

Hydroxylamines that can react with any of the long-chain hydrocarbon-substituted carboxylic acids listed above to form dispersants include 2-amino-1-butanol, 2-amino-2-methyl-1-propanol, p-(β-hydroxy ethyl)-aniline,
2-Amino-1-propatol, 3-amino-1-propanediol, 2-amino-2-methyl-1,3-propanediol, 2-amino-2-ethyl-1,3-propanediol, N- (β-hydroxypropyl)-N'-(
β-aminoethyl)-piperazine, tris(hydroxymethyl)-aminomethane (also known as trismethylolaminomethane), 2-amino-1-butanol, ethanolamine, β-(β-hydroxyethoxy)-ethylamine, Mixtures of these and similar amines can also be used, including the like.

Preferred dispersants include polyisobutenylsuccinic anhydride;
Those derived from polyethylene amines such as tetraethylene pentamine, polyoxyethylene and polyoxypropylene amines such as polyoxypropylene diamine, trismethylolaminomethane and pentaerythritol and combinations thereof. One particularly preferred dispersant combination is (A) polyisobutenylsuccinic anhydride, (B) a hydroxyl compound such as pentaerythritol, (C) a polyoxyalkylene polyamine such as polyoxypropylene diamine, and (D
) polyalkylene polyamines, including combinations with polyethylene diamine and tetraethylene pentamine;
about 0.01 to about 4 equivalents of (B) and (D) and about 0
．． 01 to about 2 equivalents of (C) are used per -equivalent of (A) (as described in U.S. Pat. No. 3,894,763). Another preferred dispersant combination is (^) polyisobutenyl succinic anhydride and (B) a polyalkylene polyamine such as tetraethylene pentamine and (
C) combinations of polyhydric alcohols or polyhydroxy-substituted aliphatic primary amines such as pentaerythritol or trismethylolaminomethane (U.S. Pat.
632,511).

The alkenylsuccinic polyamine type dispersant may further contain boron compounds such as boron oxides, boron halides, boron acids and esters of boron acids in such amounts as to provide a proportion of 0.1 to 10 atoms of boron per mole of acylated nitrogen compound. It can be denatured with About this.

and are generally taught in U.S. Pat. No. 3,087,936 and U.S. Pat. No. 3,254,025. Mixtures of these dispersants can also be used, e.g. U.S. Pat. No. 4,113
．． No. 639.

This oil is 1.0 to 10% by weight, more preferably 2.0 to 10% by weight.
7. Offi amount % of these dispersants can be included.

The dispersancy is 0.3 to 10% of a polymeric viscosity index improving dispersant, such as a copolymer of alkyl methacrylate and N-vinylpyrrolidone or dimethylaminoalkylmedacrylate, alkyl fumarate-vinyl acetate N-vinyl Pyrrolidone copolymers, ethylene-propylene copolymers post-grafted with active monomers such as maleic anhydride (which can be further reacted with alcohols or alkylene polyamines; see US Pat. No. 4,149,984); after alcohol and styrene/maleic anhydride polymers reacted with amines, ethoxylated derivatives of acrylate polymers as described in U.S. Pat. No. 3,702,300, and the like.

Magnesium and/or calcium containing additives are
Often included alone or in combination with other alkali or alkaline earth metal additives, such as sodium-containing additives, in lubricating compositions. These can be present, for example, as metal salts of sulfonic acids, alkylphenonopesulfonated alkylphenonopea alkyl salicylates, naphthinates and other oil-soluble mono- and di-carboxylic acids.

Highly basic alkaline earth metal alkaryl sulfonates are generally known, e.g. U.S. Pat. No. 3,150.08
No. 8 and No. 3.150.089. For purposes of the present invention, preferred alkaline earth metal sulfonates have a total base number
ber (TBN); measured according to the procedure of ASTM D2896) from 300 to 400.

Polyvalent metal alkyl salicylate and naphthinate materials may also be included, such as methylene and sulfur bridged materials, such as those from alkyl-substituted salicylic acids or naphthenic acids, or mixtures of one or both with alkyl-substituted phenols. Easily induced.

Basic sulfurized salicylates and methods for their preparation are shown in US Pat. No. 3,595,791.

This sulfurized metal phenolate can be considered a "metal salt of phenol sulfide", and therefore, whether neutral or basic, it can be said to be a metal salt of a compound represented by the following general formula: (where X is 1 or 2, n is 0.
1 or 2) or a polymer of such compounds, where R is an alkyl group, n and X are integers from 1 to 4, and the average of all the groups R The number of carbon atoms is at least about 9, thereby ensuring sufficient solubility in oil. Each R group can contain 5 to 40, preferably 8 to 20 carbon atoms. The metal salt is prepared by reacting an alkylphenol sulfide with a sufficient amount of a metal-containing substance to impart a desired alkalinity to the resulting sulfurized metal phenolate.

The sulfurized alkylphenol is converted by reacting with metal-containing materials, including oxides, hydroxides, and complexes, in an amount sufficient to neutralize the phenol, and if necessary the product is It is highly basicized to a predetermined alkalinity using a well-known method. A preferred method is a neutralization reaction using a glycol ether solution of the metal.

Magnesium- and calcium-containing additives, such as those described above, while otherwise advantageous, can increase the tendency of the lubricating oil to oxidize. This is especially true for highly basic sulfonates.

According to a preferred embodiment, the present invention therefore provides between 2 and 8,000
A crankcase lubricating composition is provided that also includes calcium and/or magnesium.

Magnesium and/or calcium are generally present as basic or neutral detergents such as sulfonates and phenolates, and preferred additives are basic magnesium or calcium sulfonates. Preferably, the oil contains 500-5,000 ppm of calcium and/or magnesium from the additive.

These compositions of the invention may alternatively or additionally contain other similar metal-containing detergent additives, such as barium, sodium, potassium or lithium containing additives.

The lubricating oil used in the lubricating composition may be an inorganic lubricating oil or a synthetic lubricating oil or mixtures thereof. Suitable synthetic oils are diester oils such as di(2-ethylhexyl)-sebacate, azelate and adipate; complex ester oils such as oils which can be formed from dicarboxylic acids, glycols and either monobasic acids or alcohols; silicone oils. ; sulfide esters; organic carbonates; hydrocarbon oils; and other synthetic oils known in the art. It has the additional advantage of allowing the use of basic feedstocks with poor oxidation resistance.

The lubricating compositions of the present invention can include, or typically contain, other traditional lubricating additives. provided that the additives are substantially zinc-free and phosphorous-free, and include, for example, oleic acid and its derivatives, such as N-oleylsarcosine, and oleic acid dimers and trimers, lecithin, Corrosion inhibitors such as sorbitan monooleate, dodecylsuccinic anhydride or ethoxylated alkylphenols; Pour point depressants such as copolymers of vinyl acetate and fumarate esters of coconut alcohol; and viscosity index such as olefin copolymers or polymethacrylates. These include improvers.

In copper-free oils, it is often necessary to add other antioxidants in addition to the zinc dialkyl dithiophosphate to improve the oxidative stability of the cedar oil. These supplementary antioxidants are added especially when the main raw material exhibits low oxidative stability; added.

The auxiliary antioxidants used are phenols, hindered phenols, bisphenols and sulfurized phenols, catechol, alkylated and sulfurized alkylcatechols, diphenylamine and alkyldiphenylamines, and phenyl-1-naphthylamine and its alkyls. Examples include chemical derivatives.

When small amounts of copper are included, the use of these supplemental antioxidants is generally unnecessary. However, the use of auxiliary antioxidants remains within the scope of the present invention, especially for oils operating under extremely harsh conditions where the presence of these auxiliary antioxidants is advantageous. However, this provides that the neighbor is not substantially introduced.

Additives for lubricating oils are generally supplied as concentrates in oil for incorporation into bulk lubricating oils.

Accordingly, the present invention provides a concentrate comprising an oil solution containing the following components: (i) less than 0.1% by weight of phosphorus and less than 0.1% by weight of zinc; (ii) from 1 to 50%. wt% oil-soluble sulfur-containing compounds; (i
ii) 0.005-2% by weight copper; and (iv) 0
．． 1-20% by weight of a bearing corrosion inhibitor; and optionally a dispersant selected from the group of: (al O~60, e.g. 10-60% by weight of an ashless dispersant compound; (b) O~40, e.g. 3-40% of a polymer viscosity index improving dispersant (although any viscosity index improver is usually added separately).

The concentrate may also contain other additives, such as the viscosity index improvers and detergents mentioned above. Particularly preferred concentrates also contain magnesium- and/or calcium-containing additives, and the invention therefore furthermore comprises 0.1 to 8
Concentrates are also provided that also include weight percent calcium and/or magnesium.

EXAMPLES The following examples are provided for illustrative purposes only to further illustrate some aspects of the invention.

Comparative Example 1-Vl and Examples 1 and 2 In the following comparative and inventive examples, formulations were prepared with the combinations and amounts of additives shown in Table 1 below, with the remainder being lubricant compositions. It is a suitable diluent oil and contains 0.3% by weight of sulfur. The additives used are as follows.

A is a viscosity index (V, 1.) improving dispersion additive, which is an oil solution containing 21% polyfunctional ethylene-propylene copolymer and 0.29% N by weight.

B is an unnatural dispersant, which is a 50% by weight oil solution of borated polyisoptenyl succinimide having a polyisobutenyl group with a molecular weight of about 950, and 1.6% by weight of N (!
: Contains 0.35% by weight of B.

C is an oil solution of highly chlorinated magnesium sulfonate with a TBN of 400, the magnesium content is 9.2% by weight and the sulfur content is 1.7% by weight.

D is an oil solution of overbased calcium sulfonate with a TBN of 300 and has a calcium fJ of 11.9% by weight and a sulfur content of 1.9% by weight.

E is an oil solution of copper oleate containing 4% by weight copper.

F is 3 for hindered methylene bisphenol antioxidant
It is a 0% by weight oil solution.

G is an alkylated diphenylamine antioxidant available as Irganox L-57 from Ciba-Geigy.

H is a 50% by weight oil solution of zinc cyamyl dithiocarbamate containing 6% by weight zinc and 12% by weight sulfur.

J is an orthoborate ester made from ethoxyethanol containing 5-6% boron by weight.

K is Amoco Chemical Campa = -(Amoco Che
micalCompany) from Amoco (Amoco)
2,5-bis(nonyldithio)-1,3°4-thiadiazole, commercially available as 15B, and 33
Contains % sulfur by weight.

L is an oil solution containing 12% by weight of molybdenum as oleate.

M is from Emery Company.
y) A sulfurized ester Spine whale oil product available as 9844 and containing 11.5% by weight sulfur.

These formulations were tested using the following standard tests.

○ Seq according to ASTM STP315M part ■
, m D engine test. This measures maximum and average cam+lifter wear.

Passing this test means a maximum wear of 0.02 cs (0,
0.008 inch) or less and average wear 0.01
c11 (0,004 inches) or less.

The kinematic viscosity increase in OllID was determined by the increase rate (%) within 64 hours.
) was measured at 40°C. Passing this test means
The viscosity increase within 64 hours may be 375% or less.

○ C based on ASTM 5TP509A PEIV
RC-L-38 Screener engine test, which tests bearing weight loss (BWL).
) is measured. To pass this test, BWL is 4hg
The following must be met.

The results are shown in Table 2. These results demonstrate that the present invention is highly effective in lubricants that are substantially free of phosphorus and zinc and have excellent anti-oxidation, anti-wear and anti-corrosion properties for bearings. There is. Comparative Examples ■, ■, and ■ show that the wear resistance is insufficient in the absence of bearing corrosion inhibitor. Comparative Example ■ shows that the molybdenum additive does not improve wear resistance. Comparative Example 3 shows that in the absence of the copper antioxidant, performance is insufficient even in the presence of other known antioxidants in known amounts.

Embodiments of the present invention demonstrate that the performance of the formulation is not simply the sum of the performance of the individual additives, but provides significant improvements in wear resistance, oxidation protection, and bearing corrosion protection, while improving the performance of conventional oils. It has been shown to contain a lower concentration of phosphorus than the commercially available product used.

Example I nn1Seq
, m D Maximum wear (value) 0.027F 0.054
6F Bi-average wear ((J) 0.012F
0.0236F F” Viscosity increase after 64 hours (%”) 102P 66P *CR
C-L-38 BWL (Illr) 88,3F
-P=Pass F=Fail*=Test not completed and failed after 4 hours.

-No test.

Chapter 1 IV V VI
1 20.0290F
0.028P 0.33F 0
．． 0056PO, 0013PO, 0163F
O,0O15P 0.02F
0.0023P O,0O08P104P
400+/48hrF 65P
67P--5P
3.3P11: A typical concentrate giving the above formulation.

Bottom Dan Encircle and ``Ten Daishi [I B 33.7 0.
12 CIB, 0 0.31 H3, 40, 16 J 11.2 0.56 Daisuke 2
B 35.7 C19,10,320,13 E 3.6 0.14 K 5.9 1.95 Concentrates may also contain some diluent oil to improve handling (reduced viscosity). good.

Claims (24)

[Claims] (1) Large amounts of lubricating oil, added copper present in oil-soluble form at 5-500 ppm, total sulfur content 0.5-2.0% by weight
one or more oil-soluble sulfur-containing compounds and an effective amount of a bearing corrosion inhibitor added so as to contain less than 0.05% phosphorous and less than 0.01% zinc by weight. Crankcase lubricating compositions used in automotive engines. (2) The amount of copper added to the composition is 10 to 400 p.
The composition according to claim 1, which is pm. (3) The amount of copper added to the composition is 10 to 200 p.
The composition according to claim 2, which is pm. (4) The amount of copper added to the composition is 60 to 200 p.
The composition according to claim 3, which is pm. (5) Salts of copper with C_1_0 to C_1_8 fatty acids, unsaturated carboxylic acids, naphthenic acids or alkyl- or alkenyl-substituted dicarboxylic acids with a molecular weight of 200 to 500, general formula (RR'NCSS)_nCu (where n is 1 or 2 , R and R' are the same or different and have 1 carbon atom
A composition according to any one of the preceding claims, wherein the copper is incorporated into the oil as an oil-soluble copper dithiocarbamate, copper sulfonate, copper phenolate or copper acetylacetonate having 18 hydrocarbyl groups. thing. (6) The oil-soluble sulfur compound has the formula: (RR'NCSS
)_nM, where R, R' and n are as defined in claim 5 and M represents a suitable metal, dithiocarbamates or mercaptides, sulfurized unsaturated organic compounds, sulfides, thioethers, thiophenols , thioxanthate, sulfurized ester, thioester, thioamide, thiazole or thiadiazole. (7) The composition according to claim 6, wherein the oil-soluble sulfur compound is a dialkyldithiocarbamate having 2 to 12 carbon atoms. (8) The composition according to any of the above claims, which contains 0.5 to 1.0% by weight of total sulfur and 0.1 to 0.5% by weight of sulfur as an added oil-soluble sulfur-containing compound. . (9) A composition according to any of the above claims that is substantially zinc-free. (10) The composition according to claim 6, comprising 0.5 to 3% by weight of sulfurized ester. (11) The above bearing corrosion inhibitor has the following formula: B(OR)_3 or (RO)_2B-O-B(OR)
_2, (ROBO)_3 or (RO)_2BO-R^
1-OB(OR)_2 (where R represents a substituted or unsubstituted alkyl, aryl or aralkyl group, or two R together form a substituted or unsubstituted alkylene group, and R^1 is a substituted or one or more borate esters represented by (which are unsubstituted alkylene groups) and/or thiadiazole polysulfides having 5 to 50 carbon atoms;
A composition according to any of the preceding claims, comprising a derivative or polymer thereof. (12) The composition according to claim 11, containing 0.01 to 10% by weight of boric acid ester. (13) The composition according to claim 11 or 12, wherein the borate is tris(ethoxyethyl)orthoborate or diborate of butane-1,3-diol. (14) The composition according to claim 11, comprising 0.01 to 10% by weight of 2,5-bis(t-nonyldithio)-1,3,4-thiadiazole. (15) A composition according to any preceding claim containing less than 0.005% by weight of phosphorus. (16) The composition according to claim 15, which is substantially free of phosphorus. (17) Any of the preceding claims further comprising (A) 1 to 10% by weight of an ashless dispersant and/or (B) 0.3 to 10% by weight of a nitrogen- or ester-containing polymeric viscosity index improver. Compositions as described. (18) The composition according to any of the above claims, comprising 2 to 8,000 ppm of calcium and/or magnesium. (19) The composition according to claim 18, containing 500 to 5,000 ppm of calcium and/or magnesium as basic calcium and/or magnesium sulfonate. (20) A composition according to any of the preceding claims, further comprising one or more rust inhibitors, pour point depressants, additional antioxidants, and viscosity index improvers. (21) (i) less than 0.1% by weight phosphorus and less than 0.1% by weight zinc; (ii) 1-50% by weight oil-soluble sulfur-containing compounds; (i
ii) 0.005-2% by weight copper; (iv) 0.1-20% by weight bearing corrosion inhibitor; and (v) 0-60% by weight ashless dispersant and/or 0.
A concentrate consisting of an oil solution containing ~40% by weight of a dispersant for improving the polymer viscosity index. (22) The concentrate according to claim 21, further comprising 0.01 to 8% by weight of calcium and/or magnesium. (23) Zinc-free and phosphorous-containing containing an oil-soluble sulfur-containing compound, a bearing corrosion inhibitor, an ashless dispersant and/or a polymer viscosity index improving dispersant, and a calcium and/or magnesium-containing detergent. Utilization of oil-soluble copper as an antioxidant in free lubricating compositions. (24) Contains less than 0.05 wt% phosphorus and 0.01 wt% zinc to control oxidation, corrosion and wear and to meet at least API engine service category SF and/or CD property standards. 5-500p in crankcase lubricating compositions for automotive engines
Added copper present in oil-soluble form in pm, 0.5-2.0% by weight total sulfur and the use of bearing corrosion inhibitors.