A fluorine-containing ether compound of the present invention is represented by the following General Formula (1). (In the General Formula (1), X is a trivalent atom or a trivalent atom group, A is a linking group including at least one polar group, B is a linking group having a perfluoropolyether chain, and D is a polar group or a substituent having a polar group at the end.)

[Chem. 1]

XA-B-D).sub.3 (1)

An electrorheological fluid which comprises a dispersion medium containing fluorine atoms in an amount larger than 0 wt % but not larger than 50.0 wt % and particles for electrorheological fluid use that are contained in the dispersion medium in an amount of 10-50 vol % of the total volume of the dispersion medium and the particles, the particles comprising a sulfonic-acid-group-containing polymer having a sulfonic acid group content of 30-70 wt %.

This invention provides a threaded connection for pipe or tube that has a non-sticky surface and that suppresses the occurrence of rust and exhibits excellent galling resistance and airtightness even in an extremely low temperature environment without using compound grease, a method of producing the same, and a composition for forming a solid lubricating coating on the threaded connection. A solid lubricating coating (24) formed from a composition containing a binder, a fluorine addition agent, a solid lubricant and a rust proof addition agent is coated as a topmost surface treatment coating on a contact surface of at least one of a pin and a box. Even when exposed to an extremely low temperature environment, the solid lubricating coating (24) can maintain adhesiveness and exhibit a lubricating function, can suppress the occurrence of galling of a threaded connection, and can also secure airtightness after fastening.

A coating composition for a lubricating coating film includes: (A) a phenolic resin; (B) an epoxy resin having an epoxy equivalent weight of 600 to 4000; and (C) at least one type of solid lubricant. The epoxy equivalent weight is generally defined by the number average molecular weight per the number of epoxy groups in a single molecule. The coating composition has a weight ratio of component (A) to the total weight of component (A) and component (B) of at least 50 weight %. A lubricating coating film, formed from the coating composition, has a high level of flexibility on surfaces of various base materials.

A magnetic disk of is provided, the magnetic disk having at least a magnetic layer, a carbon protective layer, and a lubrication layer sequentially provided on a substrate. In an embodiment, the lubrication layer a film formed by a lubricant having a perfluoropolyether compound A having a perfluoropolyether main chain in the structure and also having a hydroxyl group at the end and a compound C obtained from a reaction between a compound B expressed by: [Chemical formula 1] CF.sub.3(OC.sub.2F.sub.4)m-(OCF.sub.2)n-OCF.sub.3 [m and n in the formula are natural numbers.] and aluminum oxide.

This invention provides a threaded connection for pipe or tube that has a non-sticky surface and that suppresses the occurrence of rust and exhibits excellent galling resistance and airtightness even in an extremely low temperature environment without using compound grease, a method of producing the same, and a composition for forming a solid lubricating coating on the threaded connection. A solid lubricating coating (24) formed from a composition containing a binder, a fluorine addition agent, a solid lubricant and a rust proof addition agent is coated as a topmost surface treatment coating on a contact surface of at least one of a pin and a box. Even when exposed to an extremely low temperature environment, the solid lubricating coating (24) can maintain adhesiveness and exhibit a lubricating function, can suppress the occurrence of galling of a threaded connection, and can also secure airtightness after fastening.

A magnetic disk of is provided, the magnetic disk having at least a magnetic layer, a carbon protective layer, and a lubrication layer sequentially provided on a substrate. In an embodiment, the lubrication layer a film formed by a lubricant having a perfluoropolyether compound A having a perfluoropolyether main chain in the structure and also having a hydroxyl group at the end and a compound C obtained from a reaction between a compound B expressed by: [Chemical formula 1] CF.sub.3(OC.sub.2F.sub.4)m-(OCF.sub.2)n-OCF.sub.3 [m and n in the formula are natural numbers.] and aluminum oxide.

Compositions and processes are disclosed for forming hydrophobic coatings and lubricant-infused surface coatings. Coatings may be applied to various substrates without prior chemical or temperature treatment of the substrates and over large and irregular surfaces. Coatings are self-healing, antifouling, and have enhanced lifetimes.

A coating composition for imparting a hydrophobic film on a target surface is provided that includes an oil of a silicone oil or a fluoropolymer oil or a combination thereof, a resin, and a dry lubricant. A solvent is present to form a solution of the oil and resin. A coating is imparted to an applicator that in turn can transfer the coating as a hydrophobic film. The coating composition is stable and able to impart hydrophobic film even after storage for several weeks at elevated temperature. The coating composition does so through the exclusion of synthetic waxes especially including silicone waxes. A kit is also provided that includes a wiper blade having the above coating composition applied along with instructions for the securement of the wiper blade to a vehicle to impart the hydrophobic film to a vehicle windshield contacted by the wiper blade.

A coating composition for a lubricating coating film includes: (A) a phenolic resin (B) an epoxy resin having an epoxy equivalent weight of 600 to 4000; and (C) at least one type of solid lubricant. The epoxy equivalent weight is generally defined by the number average molecular weight per the number of epoxy groups in a single molecule. The coating composition has a weight ratio of component (A) to the total weight of component (A) and component (B) of at least 50 weight %. A lubricating coating film, formed from the coating composition, has a high level of flexibility on surfaces of various base materials.