A lubricant composition according to the present invention contains a fatty acid metal salt, a metal dithiocarbamate, and an additive having an effect of increasing an acid value of the lubricant composition, whereby fretting resistance performances are further improved.

The rolling bearing of the present invention is lubricated with a lubricant composition which contains a fatty acid metal salt, a metal dithiocarbamate, a phosphorous-type additive, and a basic additive, and which has a total acid value of 3.7 mgKOH/g or more. The rolling bearing makes it possible to further improve anti-fretting performance, and to reduce a decrease in fretting resistance even when used under the circumstance that fluorine-type grease penetrates into the bearing using urea-type grease.

Provided is a grease composition which contains (A) a mixed base oil containing (A1) a low-viscosity base oil having a kinematic viscosity at 40 C. of 10 to 50 mm.sup.2/s and (A2) a high-viscosity base oil having a kinematic viscosity at 40 C. of 200 to 700 mm.sup.2/s, (B) a lithium-based thickener and (C) a polymer having a kinematic viscosity at 100 C. of 1,000 to 100,000 mm.sup.2/s, and has an apparent viscosity at 10 C., as measured according to JIS K2220:2013 and at a shear rate of 10 s.sup.1, of 50 to 250 mPa.Math.s. The grease composition is excellent in pumpability and is also excellent in wear resistance under poor lubrication conditions.

Provided is an additive to grease comprising a salt including a silicon-containing phosphoric acid ester anion represented by the following formula (1).

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In the formula, R.sup.1 to R.sup.3 are independently alkyl groups having 1-4 carbon atoms. R.sup.4 is an alkyl group having 1-8 carbon atoms. n is an integer of 1-8.

The present invention is a grease composition, comprising a fluorine-based grease, a urea-based grease and a soap-based grease (a calcium complex soap thickener, a calcium soap thickener, a barium soap thickener, a magnesium soap thickener or a sodium soap thickener), and a rolling bearing in which the grease composition is filled.

A grease composition, containing a base oil (A), a urea-based thickener (B), and a polymer compound (C). The particles that make up the urea-based thickener (B) in the grease composition satisfy the following requirement (I): the particles have an arithmetic average particle diameter on an area basis as measured by a laser diffraction/scattering method of 2.0 ?m or less, and the polymer compound (C) has a number average molecular weight (Mn) of 30,000 or more and a molecular weight distribution (Mw/Mn) of 2.20 or less.

The present invention relates to a mixed complex soap based grease composition comprising a lubricating base oil; a saponifiable material; a metal oxide; an alkali/alkaline metal hydroxide; and a complexing acid. The present invention also discloses a single-step, open kettle, energy-efficient process which gives smooth textured zinc-alkali/alkaline earth metal mixed complex grease composition with relatively low thickener content while still maintaining desired consistency. The zinc-alkali/alkaline earth metal mixed complex grease composition is tailor made to have dropping point in a range of 180? C. to 300? C. comparable to lithium and lithium complex grease composition, have inherent oxidation stability, extreme pressure, anti-wear properties, and water resistance properties. The zinc-alkali/alkaline earth metal mixed complex grease composition shows excellent additive response good mechanical stability, low temperature properties, pumpability, and corrosion resistance.

This disclosure relates to a continuous process for preparing a grease thickener product in which operating conditions of the continuous process can be varied to obtain desired grease product properties. The process includes: (a) introducing a C.sub.3 to C.sub.30 hydroxy fatty acid or a C.sub.3 to C.sub.30 hydroxy fatty acid ester, and a metal base into a reaction zone; (b) operating the reaction zone at a temperature between 100 C. and 240 C. to react the C.sub.3 to C.sub.30 hydroxy fatty acid or the C.sub.3 to C.sub.30 hydroxy fatty acid ester, and the metal base, to produce a grease thickener product; (c) introducing the grease thickener product of step (b) into a flash chamber zone; and (d) operating the flash chamber zone at a temperature sufficient to remove volatiles from the grease thickener product of step (b). The continuous process conditions afford a production throughput of grease thickener product of greater than 8,000 pounds per hour.

Grease compositions may be made from an oil basestock. For example, a grease composition may include: an oil basestock having: a kinematic viscosity (ASTM D445, 40? C.) of from 320 cSt to 520 cSt, a kinematic viscosity (ASTM D445, 100? C.) of from 22 cSt to 36 cSt, a viscosity index (ASTM D2270) of from 80 to 119, a pour point (ASTM D97) of ?6? C. or less, and a saturate content (ASTM D7419) of 90 wt % or greater; and from 0.5 wt % to 15 wt % of a thickener, by total weight of the grease composition.

Provided is a grease containing a base oil and a hydrophilic nanofiber, the hydrophilic nanofiber having a thickness (d) of 0.01 to 500 nm being dispersed therein. The grease is low in an environmental load and excellent in safety on the human body and also has an appropriate worked penetration and has a high dropping point, and therefore, it is also excellent in heat resistance.