Tonen Corporation

Hitoshi Ohenoki

Hirotaka Tomizawa

Noboru Umemoto

Mikiro Arai

Toshiaki Kuribayashi

Hironari Ueda

Tomohiro Kato

The invention provides a fluid composition for a fluid coupling, which is excellent in viscosity stability and torque stability, and comprises a polyorganosiloxane base oil having a viscosity of 3,000-500,000 mm.sup.2 /sec at 25.degree. C. and at least one 5-membered heterocyclic compound incorporated in a proportion of 0.01-3.0 wt. % based on the total weight of the composition, said 5-membered heterocyclic compound being selected from the group consisting of thiadiazole derivatives and thiazole derivatives, both, having at least one monovalent group represented by the formula --S.sub.x --R.sup.6 in which R.sup.6 is a saturated or unsaturated monovalent group or atom composed of at least one atom selected from a carbon atom, a hydrogen atom, an oxygen atom, a nitrogen atom and a sulfur atom, and x is a number of 1 or greater.

Fluid composition for fluid coupling

A composition for hydraulic, lubricating and coupling is disclosed herein, which comprises organopolysiloxane and at least one additive selected from the group consisting of an anti-wear agent which is phosphorus type or sulfur type, a metal deactivator and a corrosion inhibitor. The composition according to the present invention further comprises an antioxidant. The composition according to the present invention can be used at high temperature for a long period, without showing a significant increase in viscosity.

Composition for hydraulic lubrication and coupling

A composition for hydraulic, lubricating and coupling is disclosed herein, which comprises organopolysiloxane and as an anti-wear agent at least one compound selected from those of the general formulas (I) to (IV), or an anti-wear agent of at least one compound selected from those of the general formulas (I) to (IV) together with a storage stabilizer. A composition for hydraulic, lubricating and coupling is also disclosed herein, which comprises organopolysiloxane together with a combination of two or more compounds selected from those of the general formulas (V) and (VI) as an anti-wear agent, or a combination of at least one compound selected from those of the general formulas (V) and (VI) as an anti-wear agent and a storage stabilizer. If necessary, the composition according to the present invention further comprises an antioxidant. The composition according to the present invention can be used at high temperature for a long period, without showing a significant increase in viscosity.

Compositions for hydraulic, lubricating and coupling

In the fluid for viscous coupling according to the present invention, organopolysiloxane is used as base oil, and by adding phosphorus type anti-wear agent or by adding the combination of said phosphorus type anti-wear agent with antioxidant or by adding the combination of phosphorus type anti-wear agent with sulfur type anti-wear agent and/or zinc dithiophosphate type anti-wear agent or further by adding antioxidant, it is possible to increase heat-resistant property without changing the viscosity when viscous coupling is in operation and to provide the fluid for viscous coupling with few wear fragment iron quantity and with high durability. In the fluid for viscous coupling according to this invention, organopolysiloxane is used as base oil, and by adding metal deactivator and/or corrosion inhibitor, or by adding anti-wear agent and/or antioxidant, it is possible to prevent the viscosity change for long time when viscous coupling is in operation and to provide the fluid for viscous coupling with high durability.

Growing community of inventors

Sayama, Japan

Hitoshi Ohenoki