US2358939A - Lubricants - Google Patents

Description

Patented Sept. 26, 1944 Roy Moore and F. Nelson, Scarsdale, N. Y., and Windsor Norman W. Faust, Port Arthur,

TexL, assignors, by mcsne assignments, to The Texas Company, New York. N. Y., a corporation of Delaware No Drawing. Application November 8, 1940,- Serial No. 364,840

9 Claims. ,(01. 252-43) 'This invention relates to lubricants, and more .particularly to soap-containing lubricants of improved appearance and stability.

Lubricating 'oils are frequently compounded with metallic soaps to yield fluid to solid products, In these products, as ordinarily prepared, there is a tendency for the oil to'separate from the compounded product, and this tendency may be particularly pronounced in the fluid and semifiuid products. The ordinary products also have a cloudy or opaque appearance, and for purposes of producing a product of improved appearance and stability, it i desirable to overcome this defect and provide a clear, transparent lubricant.

It is an object of this invention to provide novel stabilizing agents for soap-containing lubricants, which stabilizing agents also have the property of overcoming the cloudy or cheque appearance of the lubricants. s

It is a further object or this invention to provide an improved method of preparing soap-containing lubricants involving intensive milling of the lubricant in the presence of stabilizing agent's, whereby the stability of the lubricants is further improved.

It has been found that certain well-known emulsifiers have the property of stabilizing soapcontaining lubricants and improving the appearance of soap-containing lubricants. Inan intensive investigation of the addition ofemulsiflers to soap-containing lubricants, we have found that certain sulphonates improve theproperties of this type of lubricant, and that, in general, other emulsifiers show little or no improvement. The sulphonates which have been found to be particularly eilective are the petroleum sulphonates known as mahogany sulphonates, i. e., the oil-soluble sulphonate's produced by tI'QItr ment of petroleum oils, or fractions or extracts.

thereof, with sulphuric acid or other equivalent sulphonatins agents. These sulphonates are preferably employed; in the form of their alkali. metal salts, for example, I proportion of petroleum sulphonates to produce the desired stabilization of the lubricantdepends.

upon the soap content of the lubricant and, :in

general proportions of 2 to 20% of petroleum sulphonates, based iective.

While the stabilizer of this invention may be added to any soap-containing lubricant with'favorable results, wehave found that the stabiliaers are most eflective for liquid lubricants-contain ing from about 0.5 to 6% of a water-insoluble;

on the soap content. are sition of this invention, is

soap, such as lime soap. One type of liquid lubricant, designed particularly for the lubrication of textile machinery, which is materially improved by the stabilizers and method of preparaa lubricant comprising a mineral lubricating oil and from about 0.5 to 6% lime soap derived from animal or vegetable oils and fats or mixtures thereof. The lime soap in this type of lubricant may be replaced by a mixed base soap containing a major proportion of calcium soap and a minor proportion of sodium soap.

In order to more fully disclose the invention,

the following example is given, but it is to be understood that the invention is not limited thereto.

A base composition was prepared from the following ingredients:

of the lubricating oil were added slowly while agitating and allowing to cool until the proportion of soap was about 15% oi the total composition. The resulting product'had the appearance of a cup grease.

the sodium salts. The

In preparing a. lubricant containing about 2.5%

. mp. this base composition was thinned with a ortion of the required amount of lubricating oil (300 viscosity naphthene base oil),and suiilcient commercial mahogany sulphonates. containing about 42% of sodium mahogany 'sulphonates, was added to give a proportion of sodium mahogany sulphonates oi about 2.5% oi the soap content. This required a proportion of about 6% of the commercial mahogany sulphonates, based on the soap content.- The mixture of base composition, lubricating oil. and emulsifier was heat- 'ed with agitation in about 300 to 310, F. and

maintained at 200 to 810' 1''. until the couiposi- -tion was substantially dehydrated. After allowing the substantially dehydrated mixture to cool to about 200 F. suflicient water was incorporated in the mixture with agitation to give the composition maximum stability. .In general, the

proportion of water for maximum stability is. from 0.1 to 0.5%, and in this example the'pro-.

portion was about 0.3% of the final composition containing about 3.5% soap. The remainder of.

the lubricating oil was then added with agitation. It is preferable to-add the lubricating oil in portions as described above, but it is to be understood that all of the required amount oflubrlcating oil may be added before th step of heating to substantial dehydration.

The resulting lubricant was a clear, transparent product which showed only very slight oil separation in storage for six months. However. to further improve the product against 011' separation, it was subjected to intensive shearing stresses by running through a colloid mill several times. The intensive mixing in the colloid mill resulted in material improvementin the product especially with respect to oil separation. After six months storage the oil separation inthe product which had. been run througha colloid mill was so slight as to'be negligible .for all practical purposes.

The lubricating oil used in'the example was a naphthene base oil having the following characteristic's:

Gravity,- A. P. I- 20.8 Flash, F 3'70 Fire, F I 426 Viscosity, S. U. at 130 IL-.. 816 Color, Lovibond 6" cell 100 Pour, F 20 .lubricating oil, about 0.5-6.0% by weight of a lime soap, and about 2-20% by weight,based on the lime soap content, of an alkali metal petroleum mahogany sulphonate to maintain the transparency of the lubricant and to stabilize the lubricant against oil separation.

3. A liquid lubricant comprising a petroleum lubricating oil, about 0.5-6.0% by weight of a mixed base soap containing a major proportion of calcium soap and a minor proportion of sodium soap and about 2-20% by weight, based on the mixed base soap content, of an. alkali metal petroleum mahogany sulphonate to maintain the transparency of the lubricant and to stabilize the lubricant against oil separation.

4. A liquid lubricant comprising a petrolemn lubricating oil, from 0.5-6.0% of a lime soap, from 0.1-0.5% water, and a proportion of an alkali metal petroleum mahogany sulphonate of.

the order of 2-2070 of the linie soap content.

5. A method of stabilizing a polyvalent metal soap-containing liquid lubricant which com- I prises incorporating in the lubricant a small proportion 'ofan alkali-metal petroleum mahogany suiphonate or the order of 2-2o% of 1 the polyvalent soap content. 1

8. A-method of stabilizing a polyvalent-metal soap-containing liquid lubricant which comprises incorporating in the lubricant a small proportion of an alkali metal petroleum mahogany sulphunate, based on the polyvalent metal soap content, and subjecting the mixture to intensive shearing stresses.

7. A method of stabilizing a polyvalent metal soap-containing liquid lubricant which comprises Any suitable petroleum lubricating oil, such as a distillate or refined residual oil, having a viscosity of from 70 at 100 F. to about 150 at 210 F. can be employed. For a textile lubricant, a lowerviscosity oil of about 300 or below at 100 F. is preferred.

Other grades of lubricant having soap contents of from about 0.5 to 6% may be prepared as described in the specific example, or by equivalent methods, with the modification that the proportion of lubricating oil is adiusted to result in lubricants of the desired-soap content.

Obviously, many ,modifications and variations of the invention, as hereinbefore set forth, may

incorporating in the lubricant about 2-20% by weight, based on-the polyvalent metal soap content, of an alkali metal petroleum mahogany sulphonate. andpaseing the mixture through a col- 40 loid mill.

8. A method of preparing a stable pclyvalent metal soap-containing liquid lubricant of improved appearance and transparency which comprises mixing a mineral lubricating oil with about 0.5-8.0% by weight of a water-insoluble polyvabe made without departing from the. spirit and] scope thereof, and therefore only such limitations should be imposed as are indicated in the 6B appended claims. What we claim is:

1. A--liquid lubricant comprising a petroleum 1 lubricating oil, water-insoluble polyvalent metal soap in a proportion to maintain the fluidity of'thelubricant at ordinary atmospheric temperatures, and a small percentage .of an alkali metal petroleum mahogany sulphcnate, based on the polyvalent metal. soap content. to

2. A liquid lubricant comprising a petroleum lent metal soap, adding a small proportion of an alkali metal petroleum mahogany sulphonate,

about 240% by weight of the lime soap content, I heating to effect substantial. dehydration of the maintain the transparency of the lubricant and 06 to stabilize the lubricant against oil separation.

mixture, partially cooling, and then-adding from' ture through "a colloid mill.

. ROY I". NELSON. WINDSOR. MOORE. NORMAN w. FAUST.

0.1-0.5% by weight of water, and passing'the mix cfin'rI IcATEpF CORRECTION.

Pa -N 2 558 959,

ROY F. NELSON, ET AL.

It is hereby certified that error appears in theprinted specification of the above numbered -pewseht requiring correction asfollows: Page 2 second column, line 26, claim 5., before the vyord "soap" insert met'a1 and tha t the said Letters Patent should be. rearl W1 that the same may conform to the'record of the Signed and sealed this 16th day of January, A. D. 19b.5.

case in the P atent Office.

Leslie Frazer (Seal) Aching Commisei'oner of Patents,

' September 26, 19%.

th this correction therein