US2242260A - Lubricating composition - Google Patents

Description

Patented May 2t), 1941' v' UNITED wnarcsrmc comosrrion Carl F. Prutton, asst fleveland, Ohio, assignor,

by mesne assignments, to The Lubrl-Zol Development Co poration, Cleveland, Ohio, a corporation of Delaware No Drawing. Application January 22, 1937,

Serial No. 121,827

7 Claims. (01. 252-48) This invention relates, as indicated, to lubricants and more particularly to lubricating compositions capable of providing efllcient lubrication under extreme pressure conditions, that is, of satisfactorily maintaining a lubricating film between bearing or other metallic. surfaces operating under such extremely high pressures as would ordinarily cause seizing or scoring of such surfaces if a plain mineral lubricating oil, for example, were employed. These lubricating compositions are characterized by the fact that they are generally more effective and at the same time more stable than those used heretofore.

This application is a continuation in part of my copending application Serial No. 755,987, filed December 4, 1934 and, co-pending application Serial .No. 737,070, filed July 26, 1934.

This invention further relates to a method of preventing seizing or scoring of relatively moving bearing surfaces and of reducing the wear or friction between such surfaces. The addition of certain agents to lubricating compositions gen erally for the purpose of improving their ex treme pressure characteristics is not new. It is generally recognized that the degree of effectiveness of extreme pressure addition agents is usually directly proportional to their chemical or physico-chemical action on the bearing surfaces in producing a film which usually has an antifluxing function in preventing actual metal to metal contact, and in addition, sometimes the function of producing a film which is more strongly attached to the metal surfaces than plain lubricating oils. Also, the action of the addition agents is to provide a film characterized by the fact that the coeflicient of friction between the surfaces where such film is maintained is generally lower than when ordinary lubricants are employed.

While a certain amount of chemical or physico-chemical action by the addition agent upon the bearing surfaces is necessary and desirable in order that an extreme pressure film may be produced, the addition agent must, nevertheless, be sufliciently stable and relatively inactive so that its activity along this line remains dormant under ordinary conditions and. is only activated under the conditions of extreme pressure where its effectiveness is required for the stated purpose. In certain types of use, such as in crankcases of internal combustion engines, and in lubricants added to motor fuels and thus introduced into the apparatus to be lubricated through the combustion zone, such. relatively high temperatures are encountered that the resultant conditions tend to either decompose or render undesirably active many yp s of addition agents which are accordingly not usable in such an environment.

It is also generally accepted that many plain lubricating compositions such as refined mineral oil, due either to naturally occurring constituents in the base material or constituents in the fin-- ished product produced by refining processes, are relatively corrosive, particularly when used in conjunction with certain sensitive metals or aloys.

It is a principal object of this invention to provide a lubricating composition characterized by the fact that it contains an addition agent which may be efiective not only for the purpose of 'imparting extreme pressure characteristics to the lubricant, but at the same time likewise effective as a corrosion inhibitor for certain active constituents which may either be originally present or added to the composition for certain specific results and which will otherwise be detrlmentally active.

It is a further object of this invention to provide a lubricating composition which may be characterized by the fact that all of the above named desirable characteristics are imparted thereto by means of a single addition agent.

Other objects of this invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the features hereinafter fully described, and particularly pointed out in the claims, the following description setting forth in detail certain embodiments of the invention, these being illustrative, however, of but a few of the various ways in which the principle of the invention may be employed.

Broadly stated, this invention comprises the use as and in lubricants of organic compositions containing phosphorus and sulphur. These compositions are generally of the type which may be produced by reacting organic compositions with phosphorus and sulphur-containing reagents.

More specifically, this invention contemplates the use for the above purposes of organic compositions which (before reacting with the above referred to reagents) may desirably contain an organic oxygen compound and preferably a compound including a hydroxyl group whichmay advantageously be attached to a benzenoid ring structure.

Throughout the ensuing description of this invention, the above described material indicated as usable either by itself as a lubricant or in minor amounts as an addition agent to other lubricating compositions for the purpose of improving the characteristics of the same will, for

. convenience, hereinafter be referred to as the addition agent.

As above indicated, the addition agent is of the type produced by reacting an organic composition with certain reagents which contain either separately in combined or elemental form, or in combination, phosphorus and sulphur. The addition agent thus produced may, in most cases, be described as an organic composition containing both the elements, phosphorus and sulphur.

The type of organic base composition contemplated for use in the reaction above described, by which the addition agents are produced, is represented by the following examples:

I. Hydrocarbons, preferably containing more than four (4) carbon atoms A. Chain type (acyclic) (1) Paraflins, e. g.

Pentane Hexane Octane Decane Acyclic terpenes (2) Oleflnes, e. g.

Hexylene Di-butylene Di-iso-butylene Amylene (3) Acetylenes, e. g.

Butine, crotonylene Pentine, valerylene Hexine, hexoylene Heptine, oenanthylidene Octine, caprylidene Decine, menthene Dodecylidene Cyclic (1) Cyclo-aliphatic, e. g.

(a) Naphthenes, e. g.

Cyclopentane Cyclohexane Cyclo-octane (b) Cyclo-oleflns, e. g.

Cyclobutene Cyclopentene Cyclohexene (c) It will be noted that certain of the above, 1. e., cyclol-iexane and cyclohexene, are also hydro-aromatic compounds, 01 4 which the following are additional examples:

The hydro-diphenyls The hydro-naphthalenes, e. g., hexaand dodecahydro-naphthalenes tetraand decahydronaphthalenes The hydro-anthracenes The hydro-phenanthrenes The hydro-retenes (2) Aromatic, e. g.

Benzene Di-phenyl Naphthalene Anthracene Phenanthrene Bridged ring hydrocarbons, e. g. aromatic terpenes such as pinene Homologs of the above such as alkylated aromatic hydrocarbons, e. g. methyl, ethyl, propyl and iso-propyl, butyl, ampl, etc. benzenes, diphenyls, naphthalenes, anthracenes, phenanthrenes-more specific examples are toluene, xylene, ethylbenzene, cumene, cymene a methyl naphthalene, 'retene III.

Aromatic hydrocarbons with one or more unsaturated sidechains, such as phenyl ethylene (styrene) 5 II. Naturally occurring, or'commercially available complex compositions consisting principally of hydrocarbons A. Petroleum and petroleum derivatives, such as crude mineral oils of paraflinc, naphthenic, or asphaltic character and from various sources including the Penna., Mid-Cont., and Coastal fields; and products refined from them, e. g.

Bright stock Neutral or pale oils Steam refined oils Fuel oils Kerosene Gas oils Gasolines Paramn wax (or petroleum wax) Petrolatum Solvent extracted fractions, e. g.

Edeleanu extract Furfural extract B. Hydrocarbon materials of non-mineral origin, e. g. hydrocarbon products of vegetable origin such as certain oils obtained from the distillation of wood, etc., e. g.

Retene oil Turpentine Oxygen-bearing organic compounds (including oxygen-bearing derivatives of hydrocarbons in Groups I and II above) may be classified according to the nature of at-- tachment of the oxygen atom, viz:

(a) Directly attached to one or more carbon atoms, as in the case of (l) Ethers and analogous compounds, (2) Compounds containing the C-Oli radicle, such as the alcohols and other derivatives of carbinol (including phenols, cresols, naphthols, etc.)

(3) Compounds containing the carbonyl radicle, such as amides, aldehydes, ketones, organic acids.

(b) Indirectly attached through the means or some other atom, i. e., in the form of an inorganic radlcle,

Arsenate Chlorate Chlorite Cyanate a-Hydroxylamine Nitrate Nitrite Nitro Nltroso Oxime Perchlorate Phosphate Sulphate Sulphite Sulphinic acid Sulphone Sulpho nic acid Sulphoxide 'Ihio-sulphate The following are specific examples of suitable oxygen-bearing compounds:

Aliphatic Aromatic Alcohols Methyl alcohol Benzyl alcohol Ethyl alcohol Phenyl ethyl alcohol Propyl and iso-propyl alcohols Butyl and alcohols Amyl alcohols Lauryl alcohol Cetyl alcohol Polyhyd-roxy alcohols;

Dihydroxy alcohols,

Ethylene glycol Di-ethylene gly iso-butyl col Tri-hydroxy alcohols,

Glycerine Phenols Monohydroxy, e. g.

Phenol Alkyl phenols, e. g.

Cresols Xylenols Ethyl phenols Propyl and isopropyl phenol Amyl phenols Phenyl phenols Naphthols Polyhydroxy, e. g.

Dihydroxy, e. g.

Dihydroxy benzenes Pyrocatechin (catechol) Resorcinol Hydroquinone Dihydroxy diphenyls Tri-hydroxy. e. g.

Tri-hydroxy benzenes Pyrogallol Hydroxy-hydroquinone Phloroglucinol Others, e. g.

Rufigallol Aliphatic Aromatic Ethers Di-ethyl ethers Propyl and lsopropyl ethers Butyl and isobutyl ethers Amyl ethers Dlphenyl ethers Dixenyl ethers Dinaphthyl ethers M z'xed ethers Ethyl propyl ethers Methyl butyl ethers H ydroz Glycol ether (diethylene-glycol) Mono-alkyl esters of dihydric alcohols, e. g.

Mono -methyl ester Phenyl naphthyl ethcrs Phenyl ethyl ethers Phenyl propyl ethers y ethers Mono-methyl ethers of dihydroxy phenols,

Methoxy phenols of ethylene glycol Ketones Acetone Benzophenonc Di-ethyl ketone Di-propyl ketones Mixed Methyl-ethyl ketone Methyl propyl ketones Ethyl propyl ketones,

etc.

Naphthyl ketones ketoncs Acetophenone Ethyl phenyl ketone Propyl phenyl ketones Mixed long chain aryl ketones, such as Dibenzofuryl heptadecyl ketone Dibenzofuryl undecyl ketone as described in U. S. Pat. No. 2,-

Cycloketones Cyclohexanone Quinone Anthraquinone Aldehydes Acetaldehyde Benzaldehyde Propyl aldehydes Salicyaldehyde Naphthyl aldchydcs Acids Fatty acids, e. g.

Monocarboxylic, e. g.

Esters of an aliphatic alcohol (such as those listed above under Alcohols) and a fatty acid; (such as those listed above under Acids) e. g.

Esters of a phenol (such as those listed above under Phenols) and a fatty acid (such as those listed above under Acids) e. g.

Esters of an aromatic alcohol (such as those listed above under Alcohols) and a fatty acid (such as those listed above under Acids) e. g. Benzyl and phenyl-ethyl Acetate Propionate Butyrate Laurate Palmitate Stearate Oleate Esters of an aliphatic alcohol (such as those listed above under Alcohols) and an aromatic acid (such as those listed above under Acids) eg.

Methyl Ethyl Propyl Butyl Benzoate Amyl Phenyl acetate Lauryl Salicylate Cetyl Phthalate Ethylene Diethylene Glyceryl Esters of fatty acids derived from naturally occurring fatty oils and waxes, and of the hydrogenated acids derived from like sources, e. g.

Methyl, ethyl, butyl, etc. esters of coconut fatty acid, palm fatty acid, or the same after hydrogenation.

Naturally occurring, or commercially available complex oxygen-bearing organic compositions such as:

Non-mineral oils and waxes, e. g.

Fatty oils, including:

Animal oils,

Fish oils Lard oil Vegetable oils,

Cottonseed oil Rape seed oil Corn oil Castor oil Soya bean oil Waxes of animal or vegetable origin:

Carnauba wax v Palm wax Beeswax Japan wax Of the foregoing named organic base compositions, the following are among the more suitable:

Hydrocarbon materials Petroleum derivatives, particularly mineral oil,

for example Bright stock (preferably Pennsylvania) Neutral or pale oils Oxygen-bearing organic compounds Phenol Cresols Diphenyl ether Stearic acid Benzyl alcohol Lauryl alcohol Oxidized hydrocarbons including oxidized mineral oils Naphthenic acid Methyl stearate Butyl stearate Methyl salicylate Oleic acid Fatty oils such as lard oil Halogen-bearing organic compounds Monoand dichlor xylene Monoand dichlor cresol Paraand onthochlorphenol Monochlor pentane (chlor aznyl phenol) Chlorinated diphenyl ether, for example trichlor diphenyl ether and hexachlor diphenyl ether Monoand dichlor benzyl alcohol Methyl dichlor stearate The reagents which may be employed with the above defined organic base compositions in producing the so-called addition agents, according to this invention, are, as previously indicated, characterized by their containing free or combined phosphorus and sulphur, either present in the same or different compounds and either in elemental or combined form. Those containing the above-named elements in combined form may generally be classified as follows:

Reagents A. Phosphorus compounds 1. Compounds of phosphorus and halogen Phosphorus chloridePzCl4 Phosphorus tri-chloride-PCla Phosphorus pentachloridePCl5 Phosphorus dichlor trifluoridePClaFa 2. Compounds of phosphorus and oxygen Phosphorus trioxideP4Os (or P203) Phosphorus tetraoxidePzO4 Phosphorus pentoxidePzO5 v (or P4010) 3. Compounds of phosphorus, oxygen and halogen Phosphorus oxychloride POCla Phosphorus trioxytetrachloride-PzOzCh 4. Elemental phosphorus B. Sulphur compounds 1. Sulphur and halogen Sulphur monochloride--SzC1a Sulphur trichlorideSCl2 2. Sulphur and oxygen Sulphur dioxide-: Sulphur trioxide-SO; Sulphur heptoxide-SzOv 3. Sulphur, oxygen and halogen Sulphur monoxytetrachloride-SfiCh Sulphur pentoxydichloride-SzOsClz Sulphuric oxychlorideS0:Clz Sulphurous oxychloride-SOCl2 4. Elemental sulphur C..Phosphorus and sulphur compounds -1. Compounds of phosphorus andsulphur alone Phosphorus disulfide-PaSa (or PS2) Phosphorus disulphide-Pisa (or P283) Phosphorus sesquisulphide-PrSa Phosphorus pentasulphideP2Ss Phosphorus heptasulphide-PrSw 2. Compounds of phosphorus, sulphur and halogen I Phosphorus thiochlorida-PSC]: Phosphorus thiobromide-PSBr: Phosphorus thiobromide-PzSaBrc 3. Compounds of phosphorus, sulphur and oxygen Phosphorus su1phoxideP4S4Os 4. Compounds of phosphorus, sulphur and elements other than oxygen or halogen Phosphorus .thiocyanate-P (CNS) a 1). Reagents containing elements equivalent to phosphorus and/or sulphur 1. Compounds of phosphorus and equivalentsof sulphur, e. g. Se, for example PzSe P2883 P2585 It will be noted that since the so-called addition agent produced by the above referred to reaction shall contain both phosphorus and sulphur, and advantageously phosphorus, sulphur and oxygen, organic compounds and the reagents selected shall be such as to produce the addition agent of the desired character.

' The following is a list of particularly suitable addition agents. Since the addition agents in the list are identified according to the organic compounds and reagents used in their preparation, it

' includes typical examples of suitable organic compounds and reagents.

B. 'Reaction products of the following organic compounds with phosphorus sulphochloride (P 013) 7 Mineral oils such as bright stocks and neutrals (preferably Penn.)-

' Oxidized mineral oils Naphthenic acid Methyl stearate 0 organic compound Fatty oils such aslard oil Methyl salicylate Stearic acid Oleic acid Diphenyl Dlchlorxylene Dichlor cresol Orthochlor phenol Monochlor amyl phenol Methyl dichlor stearate Chlordiphenyl C. The reaction products of thiophenol and chlorinated thiophenol with phosphorus trichloride D. The reaction products of thiophenol and chlorinated thiophenol with phosphorus oxychloride E. The reaction products of chlorinated tricresyl phosphate (one or more chlorine atoms on one or more methyl groups) with sodium polysulphide.

F. The product produced by reacting with phosphorus oxychloride (P0013) (a) The reaction product of phenol with phosphorus pentasulphide (P255) and (b) The reaction product of orthochlorphe- 1101 with phosphorus pentasulphide.

The foregoing typical examples will he suflicient for those skilled in the art in utilizing the named reagents as well as their equivalents in producing the addition agents of this invention.

The foregoing method of preparing the addition agent contemplated herein involves the use of reagents containing both phosphorus and sulphur or separate reagents which include both phosphorus and sulphur. Methods of preparing these addition agents other than that described above may be used, for example, by reaction of the following:

A. Organic sulphur compounds with phosphorusbearing reagents, e. g. (1) Mercaptans (including thio-alcohols and thio-phenols) with (a) P0013 (2) PCI: (0) P801:

((1) P205 (e) P015 B. Organic phosphorus compounds with sulphurbearing reagents, e. g.

(1) Chlorinated organic phosphates or phosphites, (preferably with chlorine attached to aliphatic radicle) with Inorganic sulphide or polysulphide (2) Organic phophates and phosphites (preferably containing unsaturated organic radicles or products of incomplete reaction oforganic hydroxy compounds with phosphorus-bearing reagents such as P0013 and P613) with (a) BC]: (b) 8012 (c) Elemental sulphur Certain .of the which have been previously generically defined as containing both hos horns and sulphur, p p

and specifically classified in the following mannor:

(1)- Organic compounds containing both phosphorus and sulphur addition agents themselves,

may be generically, subgenerically- (2) Organic compounds containing phosphorus, sulphur and oxygen (3) Any of the foregoing compounds which contain a halogen.

A slightly different classification for certain types of the compounds usable as so-called addition agents, in accordance with this invention, is V (1) Esters of phosphorusand sulphur-containing acids, e. g.

Esters of tri-thiophospho-rus acid and Tetrathiophosphoric acid (2) Esters of phosphorus-, sulphuroxygen-containing acids, e. g.,

Esters of thiophosphorus, thiophosphoric and Tri-thiophosphoric acids (3) Any of the previously mentioned compounds which contain a halogen.

Among the specific examples of addition agents contemplated for use in accordance with thi invention which have been previously somewhat more generically defined, the following compounds may be mentioned, viz:

Tri-butyl thiophosphate Triphenyl thiophosphate Tri-benzyl thiophosphate v Tri-cresyl thio phosphates, e. g., tri- (ortho-cresyl) thiophosphate Tri-butyl tri-thiophosphate Triphenyl trithiophosphate Tricresyl trithiophosphate Tributyl trithiophosphite Triphenyl trithiophosphite Tricresyl trithiophosphite Tri- (chlor ethyl) thiophosphate 'Iri-(orthochlor phenyl) thiophosphate Tri-(orthochlor phenyl) trithiophosphate Tri-(dichlor xylyl) thiophosphate Tri- (dichlor cresyl) thiophosphate Tri-(monochlor amyl phenyl) thiophosphate Tri-(chlorbenzyl) thiophosphate Tribenz'yl trithiophosphate Tri-lauryl trithiophosphate Tri-(orthochlor phenyl) trithio-phosphite As previously indicated, the above named addition agents are usable either by themselves as lubricants or advantageously in small amounts as addition agents to other lubricating compositions. Their particular eflectiveness in .very small amounts for the purposes previously specified and hereafter explained in greater detail makes the so-called addition agents especially desirable for use in lubricating composition comprising any and conditions of higher pressure where generally temperatures lower than those in a crank case are encountered, for example in lubricating heavily loaded gears and bearings, the addition agent may be present in greater amounts, i. e., up to 5 and, in certain cases, desirably up to and phur and oxygen, and the latter will generally be found to be more effective as extreme pressure addition agents than those which contain only phosphorus and sulphur.

Certain of the addition agents have an inherent property of inhibiting corrosion of metallic surfaces by such constituents as are usually present either by virtue of being contained in the mineral oil, created in the mineral oil during the refining process, or intentionally added thereto for the purpose of producing a particular result. The

addition agents which contain halogen thus have of the well known oils usually used as lubricants,

such as mineral oil, non-mineral oils such as ani--v mal and vegetable oils e. g. rape-seed oil, castor oil, or, for certain uses, desirable combinations of suchoils. 7

It has been found that when a refined mineral lubricating oil base is used, the previously named desirable properties may be imparted thereto by the use of the named addition agents in amounts upwards of 0.10%. The amount of addition agent used. in excess of the stated minimum depends of course upon the particular use for which the resultant composition is designed; in pre-' paring a lubricant for use in the crank case of internal combustion engines, the composition will be found .to give superior-results if it contains from about 0.10% to about 2% of the addition agents.

If the resultant composition is to be used under the remarkable combination of desirable properties of imparting unusually high extreme pressure values to the composition, while at the same time rendering the same particularly stable and non-corrosive under ordinary conditions.

The oiliness factor of a lubricant, to which certain of the named addition agents have been added, has been found to be measurably improved over similar untreated lubricating compositions with which they have been compared.

The tendency of the lubricating composition to form sludges resulting either from oxidation on standing or under conditions of use is generally considerably reduced by the presence therein of the addition agent. are formed-in the lubricating composition containing the addition agents, the latter have a marked tendency to render harmless such cohstituents so that even so formed, their presence in the composition is not objectionable.

Certain of the named constituents have been found to very materially improve the viscosity index and cold test characteristics of mineral lubricating oils to which they have been added.

The stability and volatility of the addition agents should be such that under conditions encountered in service the concentration of theaddition agent in the lubricant will not be substantially reduced because of its loss by evaporation or by decomposition.

For most uses the addition agent should have a vapor pressure'less than atmospheric at a temperature of C.; and if the lubricant is to be subjected to elevated temperatures in use, less than atmospheric at C.

The stability of the addition agent should be such that decomposition shall be negligible at temperatures to which the lubricant will be exposed in service.

By the term non-corrosive as used herein and in the appended claims is meant such forms the lubricant excepting under conditions 01' ex I t-reme pressure and the like, nor cause damaging corrosion of such metallic parts.

If any sludge constituents The foregoing statements as to non-corrosiveness, stability and volatility of the addition agents applies particularly to compositions made in accordance with this invention and used as lubricants and especially when such lubricants are employed under conditions of extreme stress such as imposed by high temperature, extremely high pressure and the like. There are, however, certain uses such as in metal working, die drawing and the like where relatively more active, i. e., relatively corrosive, addition agents of the character referred to herein may be employed to advantage.

While the lubricating compositions which have been described herein as illustrating one embodiment of the invention have been generally referred to as oils, i. e., liquids, this invention is, however, also applicable to the solid and semisolid types of lubricants commonly referred to in the trade as greases, bodied oils, etc. In this connection, it should be noted that certain of the addition agents contemplated for use herein for the purpose of imparting extreme pressure characteristics to the lubricant may be employed for the additional purpose of bodying or thickening the lubricant to which they are added.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the materials employed in carrying out the process, provided the ingredient or ingredients stated in any of the following claims or the equivalent of such stated ingredient or ingredients be employed.

I, therefore, particularly point out and distinctly claim as my invention:

1. A lubricating composition comprising a halogenated aromatic thiophosphate.

2. A lubricating composition comprising a major proportion of mineral oil and a minor amount of a halogenated aromatic thiophosphate.

3. A lubricating composition comprising a major proportion of mineral oil and a minor proportion of tri(orthochlorpheny1) thiophosphate.

4. A lubricating composition comprising a maj or proportion of mineral oil and a minor amount of tri(monoch1or amyl phenyl) thiophosphate.

5. A lubricating composition comprising a major proportion of mineral oil and a minor amount of a chlor-phenyl thiophosphate.

6. A lubricating composition comprising a major proportion of mineral oil and a minor amount of a chlorbenzyl thiophosphate.

7. A lubricating composition comprising a maj or proportion of mineral oil and a minor amount of tri (chlor-benzyl) thiophosph'ate.

' CARL F. lPRUTTON.