US2223128A - Lubricating composition - Google Patents

Description

Patented Nov. 26, 1940 U-NITED' STATES 2,223,121; wamca'rnvc coMrosmoN Carl F. Prutton, East Cleveland, Ohio, asslgnor, by

mesne assignments, to The, Lnbrl-Zol Development Corporation, Cleveland, Ohio. a corporation of Delaware No Drawing. Application May 1, 1940, Serial No. 332,781

7 Claims.

This invention relates, as indicated, to lubricating compositions and more particularly to lubricatingcompositions which are predominantly hydrocarbon oil, the properties of which afiecting its use for particular purposes are improved by the addition of materials which are particularly efiective in rendering the lubricants suitable for use under conditions of extreme stress as imposed by high temperatures, high loads, etc.

10 In my co-pending applications, Ser. Nos. 737,070, filed July 26, 1934; 216,153, filed June 27 1938; and 245,226, filed December 12, 1938, I have disclosed a broad class of lubricating compositions of general utility, particularly'in the field of use where extreme service conditions are eni countered.

' My present invention relates to the discovery that a certain class of such materials is particularly suitable for .use in lubricants subjected to conditions of extreme stress such as those involved in the lubrication of heavily loaded gears, and in the lubrication of internal combustion engines operating under severe service conditions; for example, those encountered by internal combustion engines particularly of the aviation and Diesel types. I

It is the principal object of my invention,

therefore, to provide a lubricating composition.

which is especially suited for the purposes described.

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

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims; the following description setting forth in detail certain approved combinations of ingredients embodying my invention, such disclosed means constituting,

however, but one of various forms in which theprlnciple of the invention maybe used Broadly stated, this invention comprises the provision of a lubricating composition tor the purposes specified, characterized by the fact that the same contains a lubricating 011, preferably of the hydrocarbon type, as a major constituent with the properties of such composition affectinglts use as a lubricant, especially under the 1 conditions specified, by the'incorporation' therein of a minor amount, based on the amount of lubricating oil present, of a stable, oil-soluble salt of an aromatic acid of the type which may' be producedby condensing chlorbenzene with oleic acid.

' Tm: 011. Base v The 011 base of my lubricating compositionsis a lubricating oil of the type best suited for the particular 'use for which the-ultimate composition is designed. When the lubricating compositions of my invention are designed for the lubrication of automobiles, the oil base will of course T preferably consist of a refined mineral lubricating .oil of lubricating viscosity for the particular I point of application. In other words, a conven- 15 tional gear 011 maybe used for the lubrication of the gears and generally a lighter, more highly refined, oil will be used in the crank case.

This invention is applicable to lubricating compositions in whichthe base may consist 20 either entirely or in part of synthetic oils, hydrogenated oils, and voltolized oils. The oil base may also desirably contain other well' known constituents such as those which' improve the oiliness, pour point, cold test, and 25 oxidation properties, etc., of the oil. In general, compositions of-our invention may be employed with a'nycommercially available addition agents for the above defined purposes since they I are generally compatible with the same in the o amounts usually used.

THE ADDITION Aoim'rs As previously indicated, the addition agents of t l the lubricating compositions of my present invention may be broadly defined as stable oil soluble salts of aromatic acids of the type which i may be produced by condensing chlorbenzene with oleic acid. Such salts may be either organic or inorganic, the metallic salts being usually preferred. Y i The preferred metallic salts for use in such composition may be more specifically defined as those metallic salts of an aromatic acid of the 4 type which may :be produced by condensing .chlorbenzene with oleic? acid, which metallic salts are of the type in which the metal-gs present in divalent form.

Among the divalent metal salts thus included 5 Below will be found, set out in detail, the method of preparation of certain examples of my invention with results secured by the use of the same in actual engine lubrication at carefully controlled conditions in order to show comparative results.

The salts used in the examples below were all prepared from chlorphenyl stearic acid which was made as follows:

357 partsof monochlor benzene were placed in a flask equipped with an agitating device, and 46.5 parts of aluminum chloride added. Then 100 parts of oleic acid were run in very slowly so as to maintain the temperature below C. The temperature was then maintained at about 35 C. for an additional period of one hour. The contents of the flask were then added to a mixture of crushed ice and hydrochloric acid to destroy the complex. The product was washed with hot water and subjected to a distillation under a vacuum of 3 millimeters of mercury absolute pressure. The distillate coming over at a temperature below 120 C. (thermometer :bulb in vapor, pressure 3 mm. Hg.) was discarded. The distillate coming over at temperatures between 120 and 275 C. was collected as the final product.

. The bulk of the distillate came over within a temperature range of 200 to 210- C. v

The oleic acid used had the following characteristics:

Iodine .No. (Wijs) 85 Acid number 194 The product had the following characteristics: Iodine No. (Wijs) 4-8 Acid number 155-165 Percent chlorine 6.0 to 5.5

Exhmnas 7 Example I A blend of 1.33% calcium chlorphenyl stearate in a mineral lubricating oil of naphthenic type was prepared by dissolving 1.29% of chlorphenyl stearic acid in the oil, adding a 10% excess of calcium hydroxide and heating with agitation to 325 F. for 1 hours. The blend was then filtered after adding 2% of clay as a filter aid.

Example II A blend of 11% of calcium chlorphenyl stearate in the same amineral lubricating oil as used in Example I was prepared as follows:

300vparts by volume of chlorphenyl stearic acid were dissolved in 3000 parts of a 1% solution of sodium hydroxide. This mixture was heated to ture maintained at 85 C. The mixture was then allowed to stand until it had separated into two I was used instead of calcium chloride.

layers. The aqueous layer was discarded and the oil layer was then washed twice with 3000 parts of hot water and the moisture removed by heating to a temperature of 125 C. for two hours. 5

This procedure produced a concentrate containing approximately 30%. of calcium chlorphenyl stearate in mineral oil. 3%% of this concent ate was incorporated in the mineral lubricatlng oil to produce the final blend. 10

Example III Example IV A blend of 1% of nickel chlorphenyl stearate in the same mineral lubricating oil as used in Example I was prepared by the same method 25 as used in Example 11, except that an equivalent amount of nickel nitrate was used instead of 'calcium chloride.

Erample VI A blend of .25% of cobalt chlorphenyl stearate in a highly solvent-extracted Mid-Continent mo- 40 tor oil was prepared by dissolving in the mineral oil .833% of the same concentrate used in Example V.

. Enema Tasrs Tests were made of the mineral lubricating oils used in the above examples and of the blends, by means of a 2 H. P. single-cylinder, liquidcooled, fourcycle gasoline engine, rated at 1800 R. P. M. The procedure used was as follows:

The engine was loaded by means of a fan-type brake which applied a load of 1 H. P. at 1600 R. P. M. The engine was run for ten minutes at 1200 R. P. M. and'then the speed was increased to 1600 R. P. M. The following condi- 5 tions were maintained constant during the remainder of the test:

Coolant temperature. F 345 Oil temperature F 225 Airiuel ratio \Y 12.7:1

The engine was stopped at 30 hour periods for inspection of piston, piston skirt, piston rings. connecting rod bearings, etc. The engine was equipped with removable connecting-rod bearings consisting 0'1 lead-bronze with a steel backing. These hearings were weighed at the be ginning of the test and at each 30 hour inspec-. tion period. 'Before each'new test. the engine, was thoroughly cleaned and equipped with new piston, piston rings and withnew connecting 'rod bearings.

The characteristics of the ,mineraloils used to make the blends of Examples I to VI, and the characteristics of the blends are shown in the table below. The results of the engine test containing rather high percentages of the addidescribedabove are also shown in the table,

tion agents. Such concentrates may be employed In the foregoing table the symbols CaCPS, MgCPS, NiCPS and CoCPS denote respectively calcium chlorphenyl stearate, magnesium. chlorphenyl stearate, nickel chlorphenyl stearate. and cobalt chlorphenyl stearate. v

In view of the particular uses for which my compounded lubricants are intended, it is apparent that .of the salts included in the foregoing enumeration of the addition agents which may be employed, those-which are readily oil soluble arethe ones preferred for use. When these compounded oils are. designed for use under conditions where high temperatures are usually encountered, the addition agents should be stable at elevated temperatures. For use in crankcase lubricants for internal combustion engines, they should preferably be stable to the extent where there will be substantially no decomposition, -when the lubricating composition is exposed to temperatures up to 250 F.

The additionagents which are to be selected from the class described should be such that they are relatively non-corrosive with respect to the metallic surfaces with which they come in contact during use. Certain of the named addition agents may be found to be detrimentally corrosive to certain sensitive bearing metals, in which case an appropriate corrosion inhibitor may be'employed in conjunction therewith in the composition.

A lubricating composition prepared in accord- I ance with my invention and which is predominantly hydrocarbon oil may, contain from an effective amount to 20% of the salt addition agent above identified. In general, it will be found that an amount as low as .1% will often be quite effective and that amounts in excess of 10% are seldom necessary. A preferred range of concentrations for the salt in the oil is from 25% to about 2%.

It is also within the contemplation of this invention to provide the addition agents in the form of a concentratein asuitable oil, said oil Example number I v H III IV V VI Type of oil Napht Naphth. N aphth Naphth. Naphth. Naphth. %llze %)1. l x x Addition agent None CaCPS CaCPS MgCPS NiCPS CoCPS None CoCPS Percent added 1. 33 l. 0 1. 0 l. 0 1. 0 0. 25 Percentash 0 14 0. 07 0. 06 0. 12 0. l2 0 0.03 Acid number 0. 05 34 0. 31 l. 24 0. 34 l. 35 0. 04 0. 28 09 37 0. 33 0. 22 0. 33 0. 31 0. 24 0. 35

19. 7 28. 4 380 430 5 I 2 Engine test Piston condition at- 60 hrs D B B B B A+ C A+ hr 0 C C C A+ C A 120 hrs C A A 150 hrs A A Number of rings stuck at- 60 hrs 1 None None None None None None None hrs None None None None None 120 hrs None None None 150 hrs None None Percent filling of oil ring slots at- 60 hrs.--'. 90 5 5 None 50 15 None None 90 hrs 10 25 80 40 None None 120m 50 None 150m": 60 None Loss in weight of bearings, mgs. lit- 60 hrs 22 1, 075 1, 176 l, 062 3106 288 70 86 90 hrs 1,385 1 460 1,248 367 402 107 138 hrs 432 520 hrs e30 259 for further blending with a lubricating oil in the proportions desired for the particular conditions of use.

,While mineral oil, generally, is the principal ingredient of,the lubricant, it is not essential that it be the only ingredient other than the addition agent, provided that there be no adsuch addition agent. It iswithin the contemplation of this invention to include, if necessary or desirable, such other additic'l agents as are commonly added to improve the viscosity index or cold test of the lubricants; and a lubricating composition according to this invention which also has a separate film-strength or oiliness increasing agent has been found to be especially effective.

When used in conjunction with a hydrocarbon lubricating oil, it is obvious that, generally, only such amounts of the addition agent may be included as are soluble in the specified amount of oil. By the term soluble," as herein used, it is intended to indicate the ability to form not only true solutions but also any form of substantially permanently homogeneous composition when incorporated in mineraloil. With most of the compounds there is usually little difficulty, especially if the incorporation is effected in the manner described in Cornell Patent No. 2,042,880, and since quite small percentages often give remarkably improved results, it is seldom of extreme importance that the addition agents be oil-soluble in all proportions. Also, certain compounds are of value as gelling or bodying agents when used in amounts greater than are strictly soluble.

The addition agents above enumerated for use in my compounded lubricants include certain ones which may be found to at least partially decompose under conditions of extreme stress such as the very high temperature encountered in certain classes of use, while others are quite stable even under such extreme conditions.

The use for which-the lubricant is designed therefore determines the particular type of addition agent to be selected. A certain amount of decomposition, which proceeds at .a relatively slow rate, is usually not harmful. Care should be exercised; however, to select for a particular set of operating conditions, an addition agent which in the oil base used. will not decompose under such operatingconditions exceptat a low.

rate.

By the term stable" as used herein in describing'the additio'n'a'gents is meant the char-- acteristic. of the addition agents which enables them to resist decomposition in-' the oil under the condition of use for which the lubricating composition is designed.

The lubricating compositions of this invention may be prepared by first preparing the salt and then dissolving the salt in the oil base, or they may be preparedby reacting the acid in solution in all or a portion of the oil with a suitable basic compound in order to form the desired salt directly in solution in oil. In the latter case, it is frequently desirable to remove the water formed by the jreaction, or which may have been added with the basic compound, by some means such as by heating at atmospheric or sub-atmospheric pressure.

' In case the salt to be used is water-insoluble, an alternative procedure isas follows:

- An aqueous solution of a water-soluble. salt of the acid is first prepared, .for example by dissolving the acid in an aqueous solution of caustic soda 'or caustic potash. The aqueous salt solution is then emulsified with oil and-a watersoluble salt containing the cation of the desired salt is addedto the mixture. The desired salt is thus precipitated from the aqueous medium and subsequently or simultaneously dissolved by the oil medium. Separation of the aqueous and oil layers is then efiected for example by settling or centrifuging preferably at elevated temperatures. Subsequent water-washing of the oil solution to remove traces of inorganic salts may be desirable,

and removal of moisture may also be required.

This application is a continuation-in-partof my; aforesaid co-pending applications Serial Numbers 737,070, 216,153 and 245,226.

Other modes of applying the principle of the invention may be employed, change being made as regards the details described, provided the features stated in any of the following claims ortheequivalent of such be employed. I therefore particularly point'out and distinctly claim as my invention:

1. A lubricating composition containing as a principal lubricating constituent a major amount of a mineral lubricating oil with the properties of such composition ailecting its use as a lubricant improved by incorporating therein a minor an aromatic acid of the type which may be produced by condensing chlonbenzenewith oleic acid.

'3. A lubricating composition containing as a principal lubricating constituent a major amount of a mineral lubricating oil with the properties of such composition affecting its use as a'1ubri-. cant improved by incorporating therein a minor amount of a'stable oil soluble divalent metal salt of an aromatic acid of the type which may be produced by condensing chlorbenzene with oleic acid.

principal lubricating constituent a major amount of a mineral lubricating oil with the properties of such composition aiiecting its use as; a lubri- 4. A lubricating compositioncontaining as a I cant improved by incorporating therein-a minor amount of cobalt chlorphenyl stearate.

5. A lubricating composition containing as a principal lubricating constituent a major amount of a mineral lubricating oil with the propertiesof such composition affecting its use as a lubricant improved by incorporating therein a minor amount of nickel chlorphenyl stearate.

CARL r. rRn'rro'N.