Lubricant compositions, core-shell nanoparticles, and related methods are disclosed. In an exemplary embodiment, a lubricant composition includes a plurality of core-shell nanoparticles. The nanoparticles include a core, a first shell disposed on the core, and a second shell disposed on the first shell. The first shell is formed from a siliceous material and the second shell is formed from a hydrophobic material. The first and second shells form functional coatings that reduce wear and friction of parts lubricated with the lubricant composition.

Provided are compositions, additives for forming compositions, methods of operating apparatus in fluid communication with the compositions, and apparatus comprising the compositions. For example, the composition may include a polyalphaolefin component of from about 95% to about 99.5% w/w. The composition may include an additive component. The additive component may include an anti-wear agent. The anti-wear agent may be from about 0.1% to about 2% w/w. The anti-wear component may be characterized by an acid value of at least about 1 mg KOH/g. The additive component may include an aryl amine antioxidant agent, an anti-rust agent, and a metal deactivator agent. The composition may be characterized by a kinematic viscosity at 100° C. of at least about 5 centiStokes, a viscosity index of at least about 80, and an acid value in mg KOH/g of between about 0.1 and about 1.

[Problem] To provide an aqueous coating agent composition (in particular, an aqueous coating composition for lubricating films that contains a solid lubricant) which as a whole is excellent in terms of flowability, applicability, and storage stability and which is capable of forming satisfactory and smooth coating films effective in stick-slip inhibition. [Solution] The problem can be solved with an aqueous coating agent composition which comprises (A) a curable resin in an aqueous emulsion form, (B) a surfactant, (C) solid particles, (D) one or more nitrogenous heterocyclic compounds, (E) a film-forming silicone in an aqueous emulsion form, and (F) water. In particular, it is preferable that the (C) component comprise a solid lubricant. In view of the environmental regulations, it is especially preferable that the (D) component be 1,3-dimethyl-2-imidazolidinone.

A composition comprising an oil of lubricating viscosity and a compound represented by formula (I) wherein: R.sup.1 and R.sup.2 are each independently a hydrocarbyl group containing from about 4 to about 18 carbon atoms; p and q are each independently 0 or an integer from 1 to 3, and the sum of p and q is 1, 2, 3, 4, 5, or 6. The composition is effective at swelling seals. ##STR00001##

A lubricating oil composition including: a lubricating base oil; (A) a first defoaming agent, the first defoaming agent being (A1) a first polymer, or (A2) a second polymer, or any combination thereof; and (B) a second defoaming agent, the second defoaming agent being a silicone defoaming agent, the (A1) first polymer including: a first polymer chain including a polysiloxane structure, the polysiloxane structure having a polymerization degree of 5 to 2000 and being represented by the following general formula (1); and a second polymer chain bonded with the first polymer chain, the second polymer chain including a repeating unit represented by the following general formula (2), the (A2) second polymer being a copolymer of a first monomer component and a second monomer component, the first monomer component represented by the general formula (7) or (8), the second monomer component represented by the general formula (9).

##STR00001##

A lubricating oil composition including: a lubricating base oil; (A) a first defoaming agent, the first defoaming agent being (A1) a first polymer, or (A2) a second polymer, or any combination thereof; and (B) a second defoaming agent, the second defoaming agent being a silicone defoaming agent, the (A1) first polymer including: a first polymer chain including a polysiloxane structure, the polysiloxane structure having a polymerization degree of 5 to 2000 and being represented by the following general formula (1); and a second polymer chain bonded with the first polymer chain, the second polymer chain including a repeating unit represented by the following general formula (2), the (A2) second polymer being a copolymer of a first monomer component and a second monomer component, the first monomer component represented by the general formula (7) or (8), the second monomer component represented by the general formula (9).

##STR00001##

Disclosed is a lubricating oil composition capable of having a good balance of electrical insulation, seizure resistance and wear resistance. In particular, the lubricating oil composition comprises: (A) a lubricant base oil; (B) an alkaline earth metal detergent; (C) a triazole-based compound represented by the following general formula (1) or (2):

##STR00001##

wherein R.sup.1-R.sup.6 are as defined herein; (D) at least one sulfur-containing compound selected from the group consisting of a sulfur-containing heterocyclic ether compound and a sulfide compound; and (E) an ashless dispersant.

A lubricating oil composition including: a lubricating base oil; (A) a first defoaming agent, the first defoaming agent being (A1) a first polymer, or (A2) a second polymer, or any combination thereof; and (B) a second defoaming agent, the second defoaming agent being a silicone defoaming agent, the (A1) first polymer including: a first polymer chain including a polysiloxane structure, the polysiloxane structure having a polymerization degree of 5 to 2000 and being represented by the following general formula (1); and a second polymer chain bonded with the first polymer chain, the second polymer chain including a repeating unit represented by the following general formula (2), the (A2) second polymer being a copolymer of a first monomer component and a second monomer component, the first monomer component represented by the general formula (7) or (8), the second monomer component represented by the general formula (9). ##STR00001##

A lubricating oil composition including: a lubricating base oil; (A) a first defoaming agent, the first defoaming agent being (A1) a first polymer, or (A2) a second polymer, or any combination thereof; and (B) a second defoaming agent, the second defoaming agent being a silicone defoaming agent, the (A1) first polymer including: a first polymer chain including a polysiloxane structure, the polysiloxane structure having a polymerization degree of 5 to 2000 and being represented by the following general formula (1); and a second polymer chain bonded with the first polymer chain, the second polymer chain including a repeating unit represented by the following general formula (2), the (A2) second polymer being a copolymer of a first monomer component and a second monomer component, the first monomer component represented by the general formula (7) or (8), the second monomer component represented by the general formula (9). ##STR00001##

A film is formed by use of a composition containing (A) a binder resin, (B) a hard particle, and (C) a solid lubricant selected from the group containing molybdenum disulfide and graphite, wherein the composition contains tungsten carbide as the hard particle, and wherein weight ratio of (B) the hard particles and (C) the solid lubricant, (B)/(C), is in the range of 1 to 3.