Patented June 10, 1952 2,600,058 UNITED STATES PATENT OFFICE 2,600,058 LUBRICANT CONTAINING OF PHOS PHATED: HYDROXY OR. GLYCEROE Edwin C. Knowles, Glenham,. Oney P. Puryear, Fishkil, and George W. Eckert, Glenham, N.Y., assignors to The. Texas Company, New York, N.Y., a corporation:of Delaware NoDrawing. Application March 9, 1949, Serial No. 80,574. 11. Claims. (C1.252-32.5) . 2 This invention relates to a lubricating: composi forming fatty material, phosphated: castor. oil tion and particularly a-lubricating : pre and phosphated hydrogenated castor oils are spe pared from a soap of a phosphated hydroxy fatty cifically mentioned. In the following descrip acid or glyceride. tion, phosphated will be specifically One of the principal objects of the present.in 5 discussed by way of preferred example, but it is vention is to provide a lubricating composition to be understood that the inventions applies in containing as an additive to improve the lubricat the same manner to the phosphated hydrogenat ing characteristics thereof a metal soap . of a ed castor oil and to the phosphated hydroxy fatty phosphated soap-forming hydroxy fatty acid. Or acids enumerated above. glyceride thereof, such as: phosphated castor oil 10 Castor oil contains the:glyceride of ricinoleic or phosphated hydrogenated castor oil. acid, an unsaturated hydroxy C18- acid, having Another object of the invention is to provide the-formula . a lubricating grease comprising an oleaginous-liq- OH luid lubricating, base containing a sufficient pro- - or in n-a------portion of a soap of a phosphated hydroxy fatty lö CH(CH):CHCH-CH=CHCCH);coof acid or glyceride of this character to thicken the Phosphated castor oil has the phosphate:group lubricating base to a gel-like consistency. linked to the glyceride of ricinoleic acid-by, re Other objects and advantages of the invention placing the hydroxy group in the 12-position as will be apparent from the following description follows: and the accompanying claims. 20 O. a a In accordance with the present, invention, a -CH novel type of metal-soap of a phosphated hydroxy HO-P-OH. :-ch. fatty acid or glyceride is employed as an additive o -oil to impart enhanced lubricating characteristics.ior H.) H:CH.CH=CHCH.), :-oll, ll E.oleaginous E.'E'SEEG, liquid lubricating base to a gel-like as Alice. phosphated Cohen-oh castor oil-product (CFrt-o-lit available conu consistency to form a lubricating grease. In the mercially gives. the following tests: preparation of this additive or soap, the various Tasi-sf-1 try-4s as Ass - a . -- soap-forming hydroxy fatty acid glycerides and SASON: - -a or a ------Sto theirve". correspondingMassire rays any hydroxy : fatty.- - acids- a lar arerwa al-Aws first 30 Iodine number f :------. 29075 toto. 310 80 modified by phosphation to substitute a pental Phosphorus (total), percent III 35 to 6 valent phosphate group for the hydroxy group of - , 9 m ------au’ulus. the glyceride or acid with the splitting off. of This commercial, product contains; about 45 to water. This produces a complex compound con- 50% by weight of phosphated: castor oil and-55 taining both the carboxylic acid radical (as a 35 to:50% castor oil...... glyceride where the starting materialis a glycer- In-prepairing the: Soap, sufficient: basic material ide), and the phosphate acid radicals. There is employed to react with and neutralize both the sulting compound is then reacted with a sufficient carboxylic and phosphoric acid groups, thus giv proportion of a basic metallic compound, Such as ing - an oxide or hydroxide, for neutralization of the 40 O phosphate radical and for saponification of the - - H --. glyceride or fatty acid radical. I Neo-P-ONa Examples of suitable hydroxy fatty acids which b. O. are phosphated to produce the phosphated.com- CH, CHybtroff, referrfantry:-nN. pounds of the present invention are the hydroxy- 45 citchbbitor. cHe CE (CH):l-ONä. stearic acids, such as 12-hydroxystearic acid, hy- in the case of Sodium soap. When castor oil is droxymyristic acid, hydroxypalmitic acid, hy- hydrogenated, the glyceride of the unsaturated droxybehenic acid and ricinoleic acid. Likewise, ricinoleic acid is converted to the glyceride of the the corresponding glycerides of these hydroxy Saturated 12-hydroxystearic acid; and the latter fatty acids can be employed, it being understood 50 gives the corresponding phosphated 12-hydroxy that glycerine is liberated in the neutralizing glyceride which is then neutralized step with the production of the same type of in a similar manner. - metal. Soap of the complex phosphated hydroxy Whenever the expressions."phosphated soap. fatty acid. As representative. of a readily avail- forming material,” "phosphated soap-forming able and economical supply. of the raw soap- -55 hydroxy fatty acid,” “phosphated soapsforming 2,600,058 3 4. hydroxy fatty acid glyceride,” “phosphated castor liquid lubricating base' is employed to designate oil,' 'phosphated hydrogenated castor oil' and both the mineral lubricating oils and the syn similar expressions are employed in the follow thetic lubricating bases specified. ing description and claims, it is to be understood In the preparation of a grease in accordance that each designates the type of compound de s with the present invention, the particular phos scribed above wherein a pentaValent Ortho-phoS phated hydroxy fatty acid or glyceride is heated phate group has been substituted for a hydroxy With a metal oxide or hydroxide in the presence group attached to the carbon chain remote from of Water and a portion or all of the mineral lubri the carboxyl group of the hydroxy fatty acid or cating oil or other liquid oleaginous vehicle at a glyceride thereof, with the splitting off of Water. O temperature of about 175-240° F. for a period of The resulting phosphated compound thus COin about i-2 hours, utilizing sufficient of the metallic tains the unmodified COOH group of the hydroxy base to effect complete neutralization of the acid fatty acid (or the corresponding glyceride there groups of both the phosphate radical and the of) as well as unneutralized OH radicals of the carboxylic acid radical. Following this saponi ortho-phosphate group, with both the COOH fication period the product is then dehydrated by group and the OH radicals of the Orthophosphate heating at a higher temperature up to about 300 group of the compound being available for neu 330 F. for a further period of about A-3 hours. tralization in the formation of the metal Soap. Any further oil addition is made to the saponified Alkali, alkaline earth, and polyvalent metal product during dehydration, or following dehy of the phosphated hydroxy acids can be 20 dration and as it gradually cools, with continual employed in accordance with the present inven Stirring to obtain the desired consistency; and tion in relatively small proportions of the Order additional ingredients or additives, such as anti of 0.1-5.0% or greater in a mineral lubricating oxidants, anti-corrosives, extreme pressure agents, oil as an additive to impart enhanced lubricating dyes and the like, can be incorporated. The prod properties. Low concentrations of these Soaps in 2 5 uct is ordinarily drawn after cooling to a tem lubricating oil to provide a liquid lubricant impart perature of about 200-100°F. to provide the ulti added body, greater load carrying capacity (ex mate gel-like grease. treme pressure properties), and better corrosion Also, in accordance with the present invention, and rust resistance as compared with the base the properties of the resulting phosphated hy oil. As specific examples, an improved textile droxy acid Soap grease can be desirably modified lubricant is produced by the addition of about by utilizing a mixture of the phosphated hydroxy 0.5-2.0% of the sodium soap of phosphated fatty acid or glyceride with a conventional soap castor oil to a mineral lubricating oil having a forming fatty acid or glyceride for the Saponifi SUS. viscosity at 100°F. of about 50-120 to give a cation Step. Any of the ordinary saturated and heavier bodied oil; and, for protective coatings, 3: 5 unsaturated soap-forming fatty acids and fats or the addition of about 1.5-5.0% of the calcium or of the hydroxy fatty acids or hydroxy fats, includi other alkaline earth or heavy metal Soap of the ing the hydrogenated fats and fatty acids, such phosphated castor oil to a similar mineral lubri as hydrogenated fish oil acids, can be employed cating oil can be employed to give products hav for this purpose. A mixture consisting essential 40 ly of Substantial portions each of the phosphated ing a definite yield point or even a gel-like Struc hydroxy fatty acid or glyceride and an unmodi ture.Moreover, the metal soaps, particularly those of fied hydroxy fatty acid or glyceride, as well as the such elements as sodium, lithium, magnesium, foregoing mixture in major proportion together zinc and aluminum and the mixed base Soaps, with a minor but modifying proportion of a con such as sodium-calcium and Sodium-lead, have 45 ventional Soap-forming fatty acid, have been been found to produce lubricating greases having found particularly advantageous in accordance with the present invention. In addition to sapon advantageous, and in certain respects, unusual ifying a mixture of the phosphated hydroxy acid properties when added in Sufficient proportion to and other carboxylic acid with the desired metal thicken the mineral lubricating oil or other ole base or mixture of metal bases, satisfactory aginous liquid lubricating base to a gel-like con 50 greases can also be produced by separately pre sistency. Ordinarily, a proportion of Soap in forming the two or more types of soap specified excess of about 5% up to about 40-45% by Weight and then mixing them with the addition of fur on the weight of the grease composition is en" ther oleaginous liquid lubricating base to produce ployed to produce greases meeting the specifica a grease of the required consistency, tions of the different grades. Any of the various 55 mineral lubricating oils customarily employed for The following examples are set forth as repre grease making, as well as the various types of Syra sentative and illustrative of the present inven thetic liquid oleaginous lubricating bases having tion: comparable viscosities can be employed as part or EXAMPLE all of the lubricating base with these particular 60 A sodium base grease of phosphated castor oil soaps. Among the types of synthetic oleaginous was prepared as follows: 200 grams of water, 375 liquid lubricating bases which are suitable may grams of a naphthene base lubricating oil having be mentioned the oil-soluble high boiling high an SUS. viscosity at 100°F. of 307, and 370 grams molecular weight aliphatic ethers, aromatic esters, of the above mentioned commercial phosphated aliphatic mono- and dicarboxylic acid esters, 65 castor oil containing 3.7% by weight of combined phosphorus acid esters and halogenated aromatic phosphorus and having a neutralization number compounds which possess lubricating properties of 156, a saponification number of 295 and an and also have small change in viscosity for 2, iodine number of 79, were charged to a grease given change in temperature. Of the various kettle, and heating and stirring were initiated. synthetic oleaginous compounds specified, those 70 When a temperature of the kettle contents of 200 falling within the category of aliphatic dicar F. had been reached, 157 grams of a 50% aqueous boxylic acid esters and particularly the branched Solution of sodium hydroxide was added drop chain aliphatic esters, such as di-2-ethylhexyl wise over a period of 2 hour, and an additional sebacate, are preferred. In the following de 100 grams of rinse water was added in a further scription and claims, the expression “oleaginous 75 period of 5 minutes. The Saponification reaction 3,600,058 5 6 iwas continued at 200-206°F. for a further period -grease to texture change when worked under-high of 1 hour. The temperature was then gradually shearing stress, the test being carried out aside raised to 300°F. over a period of % hour, and a scribed in U.S. Patent No. 2,450,219, Ashburn and further quantity of 1900 grams of the said naph Puryear, in column 5, lines 6-19. A small change thene base lubricating oil was introduced slowly. in miniature penetration of the sample: after test Then heating and stirring at about 300-309 F. in comparison with the original is indicative of for dehydration with continued oil addition Was excellent texture stability under high shearing carried out over a period of about 4 hours, when a stress. The miniature - penetration test is de control sample taken for penetration showed an scribed in Ind. Eng. Chem, Analytical Edition, ASTM unworked penetration of 123 at 77°F. and O vol.II, page 108, February 15, 1939. a worked penetration of 210 at 80° F. The heat The grease breakdown machine test is used to - was then cut and the temparature dropped slowly determine the lubricating properties of ball bear with continued stirring to about 210 F. over a ing greases at various temperatures. The na period of 14 hours. A solution of 13.5 grams of chine employed consists essentially of a stand diphenylamine in 50 grams of the naphthene ard motor-driven rotating ball bearing. (20 mm. base lubricating oil, together with 500 grams bore x 47 mm. diameter x 14 mm. width) mount additional of the lubricating oil were then slowly edvertically and enclosed in an oil jacket icon added at this temperature over a period of 'A taining an electric immersion coil with adjust hour. The resulting product was then drawn to able rheostat for temperature control. The up obtain an excellent yield of a transparent light 20 per face of the bearing is not covered, so that yellow stiff buttery grease. observations of performance during operation A series of other metal soap greases of the com can be made. The bearing is charged with 5 mercial phosphated castor oil, including a lithium grams of the grease initially. With the system base grease, a magnesium base grease, a zinc at atmospheric temperature, rotation of the base grease, an aluminum base grease, a 3:1 25 packed test bearing is started at 3450 R. P.M. sodium-calcium mixed base grease and a 3:1 and allowed to proceed for 3 minutes, during sodium-lead mixed base, grease were also pre which time observations are taken of the general pared in a similar manner and utilizing the same nature of lubrication provided, i. e., whether or naphthene base lubricating oil. Typical tests not the grease folds over the bearing, channels, *and the characteristic appearance of the above 30 slings away from the bearing, tends to “ball up,' described sodium base and the other metal base etc. Then heat is applied to the bearing as it greases so obtained are set forth in the following continues to rotate at the same speed so as to Table I: - - - - gradually raise the temperature of the bearing Table I

. Metal Calcu-tercenat ?t.,D rop. F. E.enetra-tion, Worked77 FF. Appearance lated Unworked Sodium------13.5 485 144 293 transparent light yel lithium------: 12, 6 500- 38 269 clearlow, amber,stiff, buttery. ... light ...magnesium------" 20 340 275 344 transparentfeather. anuber, - -, -' - - - - - stringy. zinc------20 233 20l. 274 opaque ivory, soft, buttery. alumimun.----- 23.8 224 191 249 amber, transparent gel. sodium-calcium. 0 g07 28 273 transparent pale yell low, hard, buttery. Sodium-lead.---- 15 | 268 57 286 tan, stiff, buttery. In addition to the foregoing tests for dropping 50 until the grease fails to lubricate (the breakdown point and penetration, other tests were obtained point) or until a temperature of 300° F. : is on this series of greases asset forth in appended reached in about 40 minutes from the start of the ..fable I: test. Beginning at a bearing temperature of 100° Tobie Ti F., observations of performance are recorded for 55 every 25°F. temperature rise or for any significant Na Li Mg., Zn Na:Ca Na:Pb development such as texture change, expansion ------Dynamic Shear Test, Min in volume, air entrainment, channeling, leakage, triature Penetration: melting and consequent thinning, separation, dis Original.------41 45 ------40 83 coloration, vaporization, etc. After completing Final------34 113 ------35 -36 60 Lubrication-Grease Break- .. the run, the bearing is removed and cooled; and down Machine-R. T. to grease remaining. On the bearing is examined for Low.300 Temperature F------Torque. la . E. E. E E - E texture and consistency, change, discoloration, seg?rev.: i etc. and compared with the original grease. The Minis20.F. ... 8 19; 8 results obtained are compared with those secured Lubrication-TorqueMinus 30. F. Breakx - - 62.5 94.3 65 'down Machine: in the same test on a standard premium ball and Timken Bearing 80° F - F E E E ... E E roller bearing grease of known - excellent per Timken Bearing 80-250 - F------. G. E. E. P E E formance; and the performance of the test grease Federal Bearing 80° F - G E - G - G E E is rated on a comparative basis as E for excellent, Federal Bearing 80-250° F------F - G E P G G 70 GpOOr. for good, A for adequate, F for fair and P for The low temperature torque test of the fore P-poor.! I.etters denote. E--excellent; G-good; A-adequate; F--fair; going table is essentially a measure of the re sistance of the grease to : congealing and of its The dynamic shear resistance test of the fore going table is a measure of the resistance of the '75-tremelyability to low afford temperature proper conditions,lubrication suchunder as exare 2,600,058 7 8 encountered in aircraft at very high altitudes. is also determined; and grease leakage (grease . The apparatus employed for the test consists es escaping from both the bearing and housing) is Sentially of a vertically mounted hollow spindle determined by actual weight measurement or by With a No. 204K Conrad type 8-ball bearing difference. A visual inspection is made of the mounted on the bottom, and a drum on which is grease remaining on the bearing to ascertain Wrapped a coiled line for applying torque mount whether any structure or texture change has ed on the top. The bearing packed with a 60% taken place; and the penetration of a sample of capacity charge of the grease to be tested is the grease taken from the bearing after test is clamped at the inner race to the spindle, while compared with the original penetration of the the outer race is clamped immovably to a sta lii grease. A Second test procedure is conducted on tionary cup within which the bearing is inserted. the same machine in this manner, except that in The assembly is inserted with the lower bearing this case the temperature of the chamber and of end in a low temperature bath containing iso the bearing is raised gradually from an initial propyl alcohol, and the desired temperature of 80' F. to a temperature of 250 F. at the end of the bath and bearing is attained by dropping i. an hour. The test is then run at 250 F. for an Dry Ice in the bath. The drum and drum exten additional two hours before terminating the test. Sion carried at the upper end of the hollow spindle Similar readings are made as previously de ... and protruding from the bath are held in vertical Scribed. The results thus obtained are compared position by a tapered roller bearing. The line with those Secured in the same tests on a stand coiled around the drum extends over a pulley to : ard premium ball and roller bearing grease of a container into which the desired weights are known excellent performance; and overall lubri added to apply the torque load to the hollow cating performance of the test grease is generally Spindle to thereby cause rotation of the spindle reported on the basis of this comparison as E and inner race of the bearing with respect to the for excellent, G for good, F for fair and P for fixed outer race. A time of not less than two 2 :5 pOO. hours is utilized to cool the bearing to the test The foregoing liables I and II show that the temperature, and an additional Soaking period phosphated castor oil Soap greases of the present at the test temperature is permitted Such that invention show advantageous and, in certain re the test is not run until three hours from the Spects, unusual properties. The sodium, lithium start of cooling. When the desired bearing tem 30 and Sodium-calcium greases have high dropping perature and Soaking period are attained, a points, with the lithium base grease having the 2000 gram-centimeter torque load is applied in unusual dropping point above 500° F. Most of both clockwise and counterclockwise directions, the grea.SeS tested by the dynamic shear test and the number of Seconds for One rotation in show excellent to fair resistance to working each direction is observed and the readings 35 down; and practically all of the greases showed averaged. excellent performance in the rigorous grease The torque breakdown machine test is designed breakdown and torque breakdown machine tests. to evaluate the lubricating properties of greases A Sample of the 3:1. Sodium-calcium grease con used for the lubrication of anti-friction bearings. taining 0.5% by weight of diphenylamine gave Two standard 3.9370 inch Timken tapered roller 40 adequate lubrication in a 168 hour continuous bearings packed with about 25 g. each of the run at 228 F. in the torque breakdown machine grease under test, and a standard Federal Pre using a Federal ball bearing. In addition to the cision Ball Bearing No. 1211 packed with about tests listed, tests were made on the Timkin E. P. 32 g. of the grease are employed, the packed Machine on the Sodium base grease with various bearings being weighed before test. In the test loads ranging from 10 to 45 pounds OK being of each bearing, the bearing is assembled on a obtained, which indicates that the phosphated motor driven shaft supported by pillow blocks Castor oil Soap greases possess extreme pressure within a bearing housing mounted Withiin an in characteristics. sulated chamber, with a System of levers con EXAMPLE II nected to register any movement of the bearing : The following example is listed as representa housing in grams on a platform Scale, whereby tive of a lithium base grease of phosphated castor both the starting torque and the running torque oil possessing excellent low temperature and can be measured. The insulated chamber is lubricating properties which adapt it for special equipped with a copper coil tubing for the cil ized ball and roller bearing uses. 100 grams of culation of a cooling or heating medium, and water, 375 grams of an acid-treated light pressed also with an insulated cover equipped with an distillate paraffin base lubricating oil having an electric heater and a motor driven fan, whereby SUS viscosity at 100°F. of 101, and 370 grams of the temperature of the chamber and bearing the above mentioned commercial phosphated under test can be accurately controlled. The test Castor oil having a phosphorus content of 4.54% of the Timken bearings at 80 F. is made at 900 3. by weight, a neutralization number of 146, a R. P. M., and the test of the Federal bearing at Saponification number of 301, and an iodine num 80° F. is made at 1750 R. P. M., each for a period ber of 80 were charged to the grease kettle and of two hours. The instant the motor driving the heating and stirring started. When the tem test bearing is started, the first torque reading perature of the kettle contents reached 196° F., is recorded as the starting torque. then run- i. 470 grams of a 10.1% aqueous lithium hydroxide ning torque and temperature readings of the Solution were slowly added over a period of 4, bearing are recorded at one minute intervals for hour and an additional 50 grams of rinse water the first 30 minutes, and at 10 minute intervals then introduced. Saponification proceeded for 1. for the remaining 1/2 hours, while the tempera hour at 200-202 F., when the temperature was ture within the chamber is adjusted to maintain O raised to about 300 F. for dehydration. With the bearing temperature within 2 of 80 F. At the temperature maintained at 301-304 F. over the end of the run, the bearing is removed fron a period of about 2 hours, 1700 grams of di-2- the housing and weighed, whereby the weight of ethylhexyl sebacate having an SUS viscosity at the grease remaining on the bearing can be com 100 F. of 68 and a pour point below -80° F. puted. The weight of the grease on the housing 5 Were gradually added to bring the grease to de 2,600,058. 9 sired consistency and to thus obtain about a 10. 4:1 mixture of the synthetic oil with the paraffin The following example is listed as typical of a base lubricating oil in the final product. The premium type lithium base grease prepared-from heat was then cut and the product gradually a mixture of a major proportion of the men cooled with continued stirring, during which time tioned commercial phosphated castor oil with a . 13 grams of phenyl alpha-naphthylamine in 50 minor proportion of a conventional fatty acid, grams of the paraffin base oil and 0.1 gram of a Such as Stearic acid, particularly for the produc suitable dye were added. The resulting product tion of a grease having exceptional low tempera was drawn at 225 F. to obtain a hard gel-like ture properties in addition to providing excell orange-colored grease having the following cal 0 lent lubrication over a wide temperature range. culated composition: 324 grams of phosphated castor oil of the chart. Per cent by... weight acter specified above, 110 grams of triple pressed: Lithium soap of phosphated castor oil --- 14.8 stearic acid, 310 grams of an acid-treated:light Glycerine ------ressess-s-s------1.4 pressed distillate paraffin base lubricating oil have Paraffin base lubricating oil 14.8. 5. ing an SUS viscosity at 100°F. of 101, 200 grams. Di-2-ethylhexyl sebacate -- - 68.5 of water, and 513, grams of a 10.1% aqueous Phenylalphanaphthylamine -- 0.5. lithium hydroxide, solution were charged to a: Dye. ------0.002. grease. kettle and heating and stirring started. Typical tests obtained on this grease are Set Saponification was effected at a temperature of: forth in the following Table III. 20 160-190°F. over a period of 2% hours. Then the Table III temperature was raised rapidly to above 300°F. Dropping point, F------. Over 500 and maintained at about 311-324 F. for 2-hours Penetration, ASTM, 77° F.: to effect dehydration. 930 grams of di-2-ethyl UnWorked ------142 hexyl, Sebacate ... were then added slowly over.a. Worked ------286 period of 4 hours with continued stirring as the. Free alkali (LiOH)), per-cent ... 0.05 temperature dropped to about 220° F. with .8.6. Free fatty acid (as oleic), per cent ---- 0.13 grams of phenylalphanaphthylamine included in Lithium Soap, per cent ------4.8 the final portion of the added di-2-ethylhexylt Appearance ------Hard, gel-like Orange Sebacate. During continued stirring and as the Lubrication-grease - breakdown machine 30 temperature dropped to about 180° F., 100 grams R. T. to 300 F------use in A of a blend of the di-2-ethylhexyl sebacate with. Lubrication-torque breakdown machine: the paraffin base oil in the ratio of 3:1 and con Federal bearing, 80° F------E. taining 0.5 grams of phenylalphanaphthylamine : Federal bearing, 80-250 F------E Were added, followed by an additional 50 grams. Timken bearing, 80. F------E. 3. 5 of the 3:1 blend containing 0.25 grams of phenyl. Timken bearing, 80-250°F.-----...---- E alphanaphthylamine. The grease was drawn at Low-temperature torque-minus 97° F., a temperature of 174°F. and a final product of a Sec./rev. ------lil brown smooth glossy, buttery medium feather Oil separation test -50 hr. at 212 F.: grease obtained, having the following calculated: Separation, per cent.------5.2 40 composition: - Evaporation, per cent ------0.18 Per cent by weight. The oil separation test is described in Army Lithium soap of phosphated castor oil ... 17.3 Navy. Aeronautical Specification AN-G-3a, Low ------6.0: Temperature Lubricating Grease, page 5, March Di-2-ethylhexyl sebacate ------. 56.0 6, 1943. This is a measure of the resistance of Paraffin base lubricating oil ------18.6 the grease to oil bleeding and evaporation. In Glycerine ------5 this test 10 grams of the grease are placed in a Phenylalphanaphthylamine ------0.5 weighed 60 mesh screen cone supported from the Excess LiOH ------0.1 rim of a weighed 100 milliliter beaker so that the The following tests were made on this grease pointed bottom of the screen cone containing the 50 in comparison with the Ordnance Department, grease is substantially above the bottom of the U. S. Army Specification 2-134, for Low Tem beaker. This assembly is then placed in a gravity perature Instrument Grease, October 8, 1948. convection oven maintained at 212°F. for a Table IV period of 50 hours. At the end of that period, the 55 assembly is removed, cooled in a desiccator, and 2-34 Grease of the beaker and cone weighed together and the Spec. Ex.III beaker weighed separately. The final weight of Dropping Point, F------300 min. Over 500. the beaker minus the initial weight of the beaker Penetration ASTM, 77° F.: divided by the initial weight of the grease sample Unworked------. 198. 60 Worked----...------... 260-340. 280. times 100 is reported asper cent bleeding. The Free Alkali (LiOH), per cent. - - 0, 07. initial weight of the beaker plus cone and grease Free fatty acid (oleic), per cent------0.30. Oil separation-30hrs. at 22°F. per cent 5 max. 2.09. minus the final weight of the beaker plus cone Moisture Test-i0.sec. immersion.------(1) passes. and grease divided by the initial weight of the Oxidation-Norma-Hoffmann Bomb: (a) 10..p. s. i. 20 F., 400 hrs., lbs. 5 max----- 3. grease sample times 100 is reported as per cent dropper 100 hrs. . evaporation. . . . . 65 (b) copper catalyzed, 110 p.s. i., 210 The foregoing tests, including the exceptionally Low TemperatureF., 20 hours------torque--67 ------F., 2000 - r -- (2): passes. high dropping point above 500 F., the satisfac g. cm., 3.g. of grease, see.frev------r ------7. Working Stability (100,000 strokes): tory yield, the excellent low temperature torque. Penetration, ASTM, 77° F. Original . (operable at -97 F. and probably at lower tem (Inworked) ------98. peratures), the low oil separation and evapora 70 Final.------267.: tion at 212°F. for a light oil as employed, and the Dynamic Water Resistance Loss, per cent------0.25. excellent lubricating properties for ball and 1No clouding or emulsification. roller bearings over wide ranges of temperature 2 No change in grease or stain on copper. show that this is a premium type of grease of The moisture test as set forth in the foregoing unusual character. 75 2-134 Specification is made by taking . A to 1. 2,600,058 1. 12 gram of the grease on the end of a stirring rod and now on the market, with the results shown in and immersing for 10 seconds in Water in a 200 milliliter beaker. During the period of immer Table v. Table V Conventional sion, the water is observed visually to detect any Li base Low Present appearance of cloudiness or other evidence of Temperature Li base emulsification of the grease. Grease Grease The Norma-Hoffmann oxidation test is a meaS ure of the resistance to oxidation of lubricating Dropping Pt., F------366------457 Mean Hertz, Load------20------37 greases when stored under static conditions for Cu corrosion, Norma-Hoffmann Bomb-...- positive no stain, long periods of time, as when coated in thin 0. COTOSiOil. films on anti-friction bearings, motor parts, etc. Saltspray (100 hrs., 95° F.), percentrust. 50 to 60------10:5 In this test, five four-gram samples of the grease are put in flat sample dishes and placed in a The mean Hertz, load test is made with the stainless steel bomb sealed with a lead gasket in So-called four-ball EP machine as described in an atmosphere of oxygen under an initial preS 5 the U. S. Naval Engineering Experiment Station sure of 110 pounds per square inch at a tempera Report on Cooperative Evaluation of EP Lubri ture of 210 F. The pressure drop in pounds cants, May 3, 1946. This machine comprises within the bomb is then recorded at intervals of essentially a ball pot in which three a inch 100 hours up to 400 hours or until a pressure drop diameter bearing balls SKF Grade 1, are locked of 55 pounds per Square inch occurs. 20 in place by a lock ring and nut. A vertical driv The copper catalyzed test of the foregoing table ing shaft terminating in a ball chuck holder, into is conducted in the same apparatus, except that which is inserted a ball chuck containing a fourth a strip of copper is partially immersed in the bearing ball of the same type, extends down grease sample. At the end of 20 hours at 210 F. wardly into the ball pot So that the fourth ball the grease is examined for decomposition or any 25 rotates as it is pressed against the three station change in color or consistency, and the copper alry balls. The ball pot is attached to a mount strip is examined for evidence of corrosion or ing disc Supported on a thrust bearing, so that stain. the ball pot assembly is free to rotate about its The Working Stability test is described in the vertical axis; and the ball pot assembly is forced Army-Navy Aeronautical Specification AN-G-25 30 upwardly to engage the balls at predetermined for Low Temperature Aircraft Lubricating Grease, pressures by means of Weights applied to a count October 9, 1947, and is a measure of the texture erweighted lever arm acting through a pressure stability of the grease under shearing streSS. In pin, step bearing and cross-head, the latter Sup this test a mechanical worker consisting of a cyl porting the said thrust bearing. In each run, inder filled with the grease sample to be tested the balls are coated with the grease under test; and containing a plunger plate having approxi and the vertical shaft is driven at 1800 R. P. M. mately 270 holes of s inch diameter each is en for i0 Seconds at an applied load. The three ployed, and the plunger is Worked back and forth balls in the ball pot assembly are then removed through the grease at the rate of 60 double for measurement of the Scars formed by rubbing strokes per minute until 100,000 double strokes AO of the top or fourth ball on the three lower balls. have been completed. The final penetration of A new set of four balls is used for each run. This the Worked grease is then taken and compared is a measure of the extreme pressure properties with the original unworked sample. of the grease and the empirical figures of the The dynamic water resistance test of the fore table set forth the so-called extreme pressure going table is that described in Army-Navy Aero- . value, termed the mean Hertz load, which latter nautical Specification AN-G-25, LOW Tempera is based on a relationship between the wear-load ture Aircraft Lubricating Grease, Item F-4f, diagram obtained with the lubricant tested and October 9, 1947. This measures the resistance of that of a theoretically perfect lubricant, as de the grease against being Washed out of the bear Scribed by the so-called Hertz line of elastic de ing in the presence of water. Briefly, the test in formation. Each determination requires 20 to 27 volves the 204K Conrad ball bearing mentioned ten-second runs at prescribed increasing loads above pack with 4 grams of the grease and up to welding, with Subsequent measurement of clamped in a tight fitting housing which allows Wear-Spot diarieters formed On the test balls. the inner race to rotate. The latter is mounted The division of a factor, supplied for each applied on a horizontal shaft and rotated at 600 R. P. M. 5 load, by the wear-spot diameter is made; and while a fine stream of distilled water is directed the results are averaged to yield a numerical against the end plate of the bearing housing just evaluation of the extreme pressure properties of above the Outer opening of the bearing housing. the grease. A higher numerical value represents This operation is continued for one hour, when a closer approach to the theoretically perfect the loss in weight of the dried bearing is then re C) lubricant. - - ported as grease loss; and this loss in weight di The Salt spray test is designed to evaluate the vided by the Weight of the grease used in packing ability of a coating of the grease to protect metal the bearing is reported as the percent loss. Specimens, Such as boiler steel specimens, against The tests of the foregoing table show that this corrosion in the presence of Salt or sea water grease easily passes the difficult requirements of spray. In this test the metal specimens coated the 2-134 Specification. In addition, the high with the protective layer of the grease under test dropping point, the very low time required for are supported at a 45° angle in an enclosed salt one revolution at -67 F. in the low temperature spray box held in an inclined position. An atom torque test, and the excellent working stability izer consisting of two nozzles arranged at right and Water resistance of this grease make it out angles is mounted in the lower portion of the Standing. inclined box, one nozzle being connected to a Another batch of this lithium base grease of source of clean compressed and water-saturated the same formulation was tested in comparison air under a pressure of 12-15 pounds per square with a conventional lithium base low temperature inch, with the other nozzle opening into the bot grease prepared from hydrogenated castor oil 75 tom of the box to draw salt solution up through 2,600,058 13 14 this nozzle, atomizing it in the form of a very 3. A lubricating grease according to claim 2, fine mist. An inclined baffle is mounted between wherein the oleaginous liquid lubricating base the atomizer and the specimens under test to consists of a major proportion of an oil-soluble keep the spray from impinging directly on the high molecular weight high boiling liquid ali specimens. A synthetic Sea water Solution is used phatic dicarboxylic acid ester within the lubri as the salt spray, this synthetic sea water Solu cating oil viscosity range and possessing lubri tion being prepared as follows. A stock solution cating properties and a minor proportion of a containing 10 grams of KC, 45 grams of KBr, mineral lubricating oil, and M of the metal soap 550 grams of MgCl2.6H2O and 110 grams of is lithium. CaCl2.6H2O with sufficient distilled water to make 0 4. A lubricating grease according to claim 3, 1 liter, is prepared. Twenty milliliters of this wherein the said aliphatic dicarboxylic acid ester stock Solution is then mixed with 23 grams of is di-2-ethylhexy sebacate. NaCl and 8 grams of Na2SO4.10H2O, and With 5. A lubricating grease comprising an oleagi sufficient distilled water to make up to 1 liter. nous liquid lubricating base thickened to a gel As shown by the table, the operation is continued like consistency with a proportion in excess of for 100 hours at 95° F., and then the specimens 5% and up to 45% by weight based on the grease are removed and the percentage area of the speci of lithium soap consisting of a major proportion mens coated by rust is determined. of the lithium Soap of phosphated castor oil and As shown by the foregoing Table W, this lithium a minor proportion of lithium soap of a satu base grease of the present invention has a higher 20 rated soap-forming fatty acid. dropping point, higher load carrying capacity 6. A lubricating grease according to claim 5, (mean Hertz load), greater resistance to Salt wherein the lithium soap of the Saturated Soap spray, and better copper corrosion protection forming fatty acid is lithium Stearate. than the premium type of lithium base low tem 7. A lubricating grease comprising an oleagi perature grease now employed. 25 nous liquid lubricating base thickened to a gel While the foregoing examples illustrate pre like consistency with a proportion in excess of ferred types of greases prepared from the com 5% and up to 45% by weight based on the grease mercial phosphated castor oil, which consists a sodium soap of phosphated castor oil. roughly of about equal proportions of phosphated 8. A lubricating grease comprising an oleagi castor oil with unmodified castor oil, it is to be 30 nous liquid lubricating base thickened to a gel understood that advantageous types of greases like consistency with a proportion in excess of as well as improved liquid lubricants can be pre 5% and up to 45% by weight based on the grease pared from phosphated Castor oil alone, or phoS a mixed base sodium-calcium soap of phosphated phated hydrogenated castor oil alone, or mixtures castor oil. thereof. Likewise, the various other mentioned 35 9. A lubricating grease comprising an oleagi phosphated Soap-forming hydroxy fatty acids or nous liquid lubricating base containing in excess their glycerides can be used in a similar manner. of 5% and up to 45% by weight based on the In order to obtain the advantages of the phoS grease of a metal soap of a phosphated hydro phated type of Soap in the preparation of lub genated castor oil Sufficient to thicken said lub ricants or greases of the present invention, it is 40 ricating base to a gel-like consistency. desirable to employ as the soap-forming car 10. A lubricating grease comprising an oleagi boxylic acid or glyceride constituents a mixture nous liquid lubricating base as the major con containing at least about 25% by weight of the stituent and a proportion in excess of 5% and phosphated hydroxy fatty acid or glyceride, with up to 45% by weight based on the grease of the balance being composed of unmodified hy 45 metal Soaps of a mixture consisting essentially droxy fatty acid or glyceride, or conventional of phosphated castor oil and castor oil to thicken soap-forming fatty acid or glyceride, or mixtures said lubricating base to a gel-like consistency, thereof. said phosphated castor oil constituting at least Obviously many modifications and variations 25% by weight of said mixture. of the invention as hereinbefore set forth may 50 11. A lubricating grease according to claim 10, be made without departing from the spirit and wherein said mixture consists essentially of scope thereof, and therefore only such limitations about 45-50% by weight of phosphated castor should be imposed as are indicated in the ap oil and 55-50% by weight of castor oil, and pended claims. the metal of said soaps is lithium. We claim: 55 EDWIN C. KNOWLES. 1. A lubricating grease comprising an oleagi ONEY. P. PURYEAR. nous liquid lubricating base containing in excess GEORGE W. ECKERT. of 5% and up to 45% by weight based on the grease of a metal soap of a phosphated Soap REFERENCES CITED forming material selected from the group con 60 The following references are of record in the sisting of a phosphated soap-forming hydroxy file of this patent: fatty acid and a phosphated soap-forming hy UNITED STATES PATENTS droxy fatty acid glyceride sufficient to thicken Said lubricating base to a gel-like consistency. Number Name Date 2. A lubricating grease comprising an oleagi 65 2,128,946 Katzman ------Sept. 6, 1938 nous liquid lubricating base thickened to a gel 2,142,998 Chittick ------Jan, 10, 1939 like consistency with a proportion in excess of 2,228,658 Farrington et al. ----- Jan. 14, 1941 5% and up to 45% by weight based on the grease 2,294,817 Van Dijck ------Sept. 1, 1942 of a metal soap of phosphated castor oil hav 2,345,734 Dickey et al. ------Apr. 4, 1944 0. 2,356,754 Farrington et al. ---- Aug. 29, 1944 ing the formula, 2,450,222 Ashburn et al. ------Sept. 28, 1948 O 2,450,254 Puryear et al. ------Sept. 28, 1948 Mo--ont 2,450,255 Puryear et al. ------Sept. 28, 1948 O O FOREIGN PATENTS CHCH-)-CHCH-CH=CHCH--OM 75 Number Country Date Where M is an alkali metal. ... 424,380 Great Britain ------Feb. 20, 1935