DE953550C - Lubricating greases - Google Patents

Description

Lubricating greases The subject of patent 942 526 is the composition of lubricating greases based on mineral or synthetic lubricating oils with a content of 5 to q.o weight percent sodium soaps of saturated fatty acids, with 12 to 24 carbon atoms as a thickener and anhydrous trisodium phosphate.

In accordance with the present invention, lubricating greases contain trisodium phosphate in the form of a complex; salt with the sodium soaps of saturated fatty acids with i2 to 24 carbon atoms.

The lubricating greases of the invention remain at high temperatures and very high shear rates are stable and are particularly useful for lubrication of roller bearings, such as ball and roller bearings.

The grease is made by having a suitable grease Oil, preferably rapeseed oil, or mixtures of fatty acids and glycerine etc. with moderate Temperature in the presence of only part of the base lubricating oil saponified. Then the saponified mixture is heated to about 2q.6 to 3o2 ° with it the glycerine released during the saponification reacts with the saponifying agent. The glycerin is apparently converted into aerolein, which in turn one undergoes further reaction resulting in a low molecular weight salt product leads. The exact mechanism of this reaction is not known. One can assume that the glycerin is dehydrated and the resulting aerolein or a Dimer of the same reacts with the excess alkali. The saponifying agent is used in particular NaOH, in excess of the amount required to saponify the fat or the fatty acid and to react with the glycerine or its decomposition products is. This excess alkali is combined with the acid of phosphorus at high temperature, at least 2i8, advantageously above 232 °. brought into reaction.

In this way the phosphorus salt is introduced into the soap in such a way that that there are no salt crystals in the finished fat, even with a microscope of high resolution used. It can be assumed that in this way of working a complex of salt and soap is formed, which includes the phosphate, but in any case no salt crystals are found. The product is essential differed from that which one can get according to the main patent by simply adding Trinatrium phosphate is added to the fat. Usually a fat starts with one relatively high. Soap content made. It is then followed by oil can be blended by adding lubricating oil in quantities from 75 to i250 / 0. Thereon the product blended with oil is against an excretion of oil and mechanical Decomposition stabilized in use by having it in a mechanical processor, a homogenizer or grinder high-speed shear stress fields suspends.

Such a homogenized fat only needs to contain 6% soap. Mineral oils are usually preferred, but synthetic esters, polyglycols, are also preferred and other known synthetic oils are suitable.

For the production process of the complex salt is in the present Patent no. Protection claimed. The product of the invention is preferred n.us about 65 to 85% lubricating oil, advantageously mineral lubricating oil, the soap content of the fat is between 10 and 35 percent by weight and the phosphate content between about 0.5 to 30/0. You can also use the usual additives such. B. o, 25 up to 2% phenylnaphthylamine as an anti-oxidant, and similar amounts of an oil-soluble one Sulfonates to give the grease a further anti-rust effect, if this is of particular importance. For optimal behavior in the presence of different people Non-ferrous metals can be added o, i to i% of a good metal deactivator, z. B. Di-salicylalpropylenediamine.

Example A mixture of the following composition was prepared: Components by weight Rapeseed oil ............................. 22.00 Sodium Hydroxide ................. 6, oo Sodium Petroleum Sulphonate Concentrate in Oil, 50:50 ......................... i, 00 Phenyl-a-naphtylami, n .............. i, 00 Metal de-activator ............... 0.50 Mineral oil base, viscosity 5o SSU at 98.9 ° ....................... 69.5o i 00, 00 Orthophosphoric acid ................ +1.33

Claims (2)

PATENT CLAIMS: i. Lubricating greases marked according to patent 9q.2 526 by a content of trisodium phosphate in the form of a complex salt with the sodium soaps of saturated fatty acids with 12 to 2q. Carbon atoms. 2. Lubricating greases Claim i, characterized in that the sodium soap fatty acid component is da.ß of the complex salt consists of soaps from rapeseed oil.