Provided is a lubricating grease used for lubricating mechanical elements having a reciprocating sliding ball interposed therebetween and maintaining flaking resistance even under a high load in mechanical elements having a reciprocating sliding ball interposed therebetween. The present invention therefore provides a grease composition comprising a base oil (a), a diurea compound (b), an amide compound (c), and a thiophosphorous compound or a thiophosphoric acid ester compound (d), wherein the diurea compound (b) includes a compound represented by Formula (1) R.sub.1—NHCONH—R.sub.2—NHCONH—R.sub.3 (1) wherein R.sub.1 and R.sub.3 represent an acyclic aliphatic hydrocarbon group having from 8 to 20 carbon atoms, and R.sub.2 represents a diphenylmethane group.

The invention relates to aqueous composition comprising water-soluble glycerin-based polyalkylene glycols as synthetic base oils as well as the use of the composition and the glycerin-based polyalkylene glycols as or in metalworking fluids, wherein the glycerin was consecutively alkoxylated in the following order: first with propylene oxide, followed by ethylene oxide and finally with propylene oxide.

No studies have been made regarding what kinds of refrigerants should be used in a refrigeration cycle device for a vehicle. An air conditioner (1) for a vehicle includes a refrigerant circuit (10) and a refrigerant that is sealed in the refrigerant circuit (10). The refrigerant circuit (10) includes a compressor (80), a first heat exchanger (85), which serves as a heat dissipater in a dehumidifying heating mode, an outside-air heat exchanger (82), a cooling control valve (87), and a second heat exchanger (86), which serves as an evaporator in the dehumidifying heating mode. The refrigerant is a refrigerant having a low GWP.

Provided are a lubricant composition which is advantageous in that, when applied to a contact area of metal parts, the lubricant composition can suppress generation of rust and can exhibit excellent lubricating performance, and a bearing the lubricant composition having sealed therein. A lubricant composition comprising at least one dicyclic liquid crystal compound represented by the following formula (1), at least one tricyclic liquid crystal compound represented by the following formula (2), and halogen ions, wherein the content of the halogen ions in the lubricant composition is 1 to 900 ppm.

##STR00001##

The present invention provides a lubricant composition comprising a base oil of lubricating viscosity, wherein the base oil comprises an ether base stock of formula (A), where: R.sub.a and R.sub.b are aliphatic hydrocarbyl groups and may be the same or different; the lubricant composition further comprising at least one aminic anti-oxidant and at least one phenolic anti-oxidant. In some embodiments, the ether base stock has the formula (1), where: R.sub.1 R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are as defined herein. The lubricant composition may be used for lubricating a surface in an internal combustion engine as well as for improving the fuel economy performance and/or piston cleanliness performance of an engine and/or a vehicle, such as an automotive vehicle associated with an internal combustion engine. ##STR00001##

A lithium complex hybrid grease is based on a lithium complex grease in combination with a PFPE grease. The lithium complex hybrid grease can be used at higher temperatures, does not form layers in the process, and exhibits a low hardening tendency. The lithium complex hybrid grease is usable in components in the automotive field and in the industrial field.

A dielectric nanolubricant composition is provided. The dielectric nanolubricant composition includes a nano-engineered lubricant additive dispersed in a base. The nano-engineered lubricant additive may include a plurality of solid lubricant nanostructures having an open-ended architecture and an organic, inorganic, and/or polymeric medium intercalated in the nanostructures and/or encapsulate nanostructures. The base may include a grease or oil such as silicone grease or oil, lithium complex grease, lithium grease, calcium sulfonate grease, silica thickened perfluoropolyether (PFPE) grease or PFPE oil, for example. This dielectric nanolubricant composition provides better corrosion and water resistance, high dielectric strength, longer material life, more inert chemistries, better surface protection and asperity penetration, no curing, no staining, and environmentally friendly, compared to current products in the market.

Provided is a lubricant composition including a bicyclic liquid crystal of formula (1), and a tricyclic liquid crystal compound of formula (2), and having a mixing mass ratio of the bicyclic liquid crystal compound and tricyclic liquid crystal compound of 95:5 to 15:85. The composition is suitable for use in a clean environment, under a high vacuum, under high temperature and a bearing.

##STR00001##

R.sup.1 and R.sup.2 are the same or different from each other, and each is —OCH.sub.2CH.sub.2CH(R′)CH.sub.2CH.sub.2OR

##STR00002##

R.sup.11 and R.sup.21 are the same or different from each other, and each is —OR. R.sup.12, R.sup.13, R.sup.22 and R.sup.23 are the same or different from each other, and each is hydrogen or —OR. R is a linear or branched C.sub.nH.sub.2n+1, 1≤n≤20 and R′ is methyl or ethyl.

Provided is a lubricant composition including a bicyclic liquid crystal of formula (1), and a tricyclic liquid crystal compound of formula (2), and having a mixing mass ratio of the bicyclic liquid crystal compound and tricyclic liquid crystal compound of 95:5 to 15:85. The composition is suitable for use in a clean environment, under a high vacuum, under high temperature and a bearing. ##STR00001##
R.sup.1 and R.sup.2 are the same or different from each other, and each is —OCH.sub.2CH.sub.2CH(R′)CH.sub.2CH.sub.2OR ##STR00002##
R.sup.11 and R.sup.21 are the same or different from each other, and each is —OR. R.sup.12, R.sup.13, R.sup.22 and R.sup.23 are the same or different from each other, and each is hydrogen or —OR. R is a linear or branched C.sub.nH.sub.2n+1, 1≤n≤20 and R′ is methyl or ethyl.

A lubricating oil composition prepared by blending a base oil (A) containing a compound (A1) that is an ester or ether and has two or more aromatic rings, with a polyalkylene glycol (B) is provided. The lubricating oil composition has a high density (i.e., a high bulk modulus), a high viscosity index, and excellent shear stability.