US2551525A - Stabilized lubricants - Google Patents

Description

Patented May 1, 1951 2,551,525 STABILIZED LUBRICANTS Robert E. Burk, Wilmington, 051., and Everett Hughes, Cleveland Heights, Ohio, assignors to' I The' Standard Oil Company, Cleveland, Ohio, a corporation of Ohio No Drawing. ApplicationxNovember 23, 1943, Serial No. 511,472, which is a division of'application Serial No. 424,362, December 24, 1941.

Divided and this application May 19, 1948, Se-

rial No. 28,055

1 Claim.

The present invention relates to lubricants, this application being a division of our application Serial No. 511,472, filed November 23, 1943, now Patent No. 2,468,031, which is a division of application Serial No. 424,362, filed December 24, 1941, now Patent No. 2,346,357, and it has among its objects the provision of improved lubrication in high temperature, such as in internal combustion engines. Other objects and advantages will appear as the description proceeds.

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

The lubricant base may be a usual lubricating oil of viscosity desired in view of particular duty contemplated, or for instance 45 to 200 sec. S. U. at 210 F. We have found that salts of metals having oxidation activity or which are oxidation catalysts not particularly at crankcase temperature but at higher temperature promote diminution of carbonaceous deposits outstandingly, and in combination with what we term an antioxidant give results much better than the total of the respective agents alone, anti-oxidant here having a meaning not as with gasoline but as an inhibitor for metal catalysts such as iron, copper, or lead. It is particularly remarkable that an agent of oxidizing character and whose activity tends primarily to be antagonistic to anti-oxidant action should work to these ends. The salts of metals constituting the oxidation catalysts comprise: naphthenates; salts of acid radicals such as of tall oil or sulphurized tall oil; acids derived from the oxidation of petroleum fractions or polymers; xanthic, i. e. acids of the type :5 ROCSH in which R is alkyl, aryl, alkaryl and sufficient to solubilize the metal compound; medium molecular weight fatty acids chosen so that the resulting salt will have 15-30 carbon atoms; acids derived from saponified wool fat (degras) with or without the alcohol, and the wool fat may be sulphurized, e. g. with P2S5, before or after hydrolysis; and for conciseness such acids are hereinafter designated organic acids of low volatility, the stated salts of which promote diminution of carbonaceous deposits. The naphthenates may also be chlorinated or halogenated, and in some cases sulphurized. The metals above referred to are chromium, also vanadium, manganese and molybdenum. In general, to 2 per cent, or more, up to 3 per cent, of the metal compound may be used. The metal salts are used with the said anti-oxidant agents. These agents comprise sulphur-containing compounds, as P285 treated degras, P285 treated polyolefins, and P255 treated distilled cashew nut shell oil. The reaction between cashew nut shell oil and phosphorus sulphide is disclosed in the patent to Hughes No. 2,411,160, in the third paragraph thereof. Up to 3 per cent, preferably 4 to 2 per cent of such agent additive to the metal compounds may be employed.

As an example: a lubricant is made up of S. A. E. 20 lubricating oil and 0.5 per cent of chromium naphthenate and 1.5 per cent of the reaction product of P2S5 on degras.

As another example: A lubricant is made up with a similar oil and 0.5 per cent of chromium oil- 0.5% Or 9 312123 5,3

PQSI degras Carbon Residue at- 525 F F F 750 F A- A-- Detergency:

Carbon suspension O- A Ox dation test A- A Oxidation Test:

Deterioration A- A+ Corrosiveness A- 11-]- The carbon residue is determined by exposing a 2.5 g. sample of the lubricant in a mm. diameter Petri glass dish in an electric furnace for 16 hours at 525 F., followed by 6 hours at 750 F. The carbon suspension is determined by suspending 5 per cent by volume of carbon in the lubricant, and a cc. sample of the suspension in a 100 cc. graduate is set in an oven at 200 F., and the number of cc. of clear oil is measured 3 at intervals. The oxidation and lacquer is .determined by exposing the lubricant in the presence of metals, iron and copper, at a temperature of'3'10' F. for 65mins byblowin'gair through at the rate of '30 liters per hour.

Other modes of applying the principle of the invention may be employed, change being made as regards the detail described, providedthe features stated in the following claim, or the equivalent of such, be employed.

We therefore particularly point out and distinctly claim as our invention:

A lubricant promoting combustion of deposits in the combustion zone of internal combustion engines and producing high stability-in the crank 1'6 2,301,795

4 case, which comprises a lubricating oil and A; to 3 per cent of the reaction product of phosphorus sulphide on cashew nut shell oil, and to 3 per cent of chromium naphthenate.

ROBERT E. BURK. EVERETT C. HUGHES.

10 file of'this patent:

UNITED STATES PATENTS Number Name Date 2,169,634 Cantrell et al. Aug. 15, 1939 Proell Nov. 10, 1942