Provided is a fluorine-containing ether compound that can be suitably used as a material for a lubricant for a magnetic recording medium, capable of forming a lubricant layer having excellent chemical substance resistance and wear resistance even when the thickness is small. A fluorine-containing ether compound represented by the following formula (1):
R.sup.1—R.sup.2—CH.sub.2—R.sup.3—CH.sub.2—R.sup.4—R.sup.5  (1) In the formula (1), R.sup.3 is a perfluoropolyether chain. R.sup.2 and R.sup.4 are divalent linkage groups having a polar group, and may be the same or different. R.sup.1 and R.sup.5 are terminal groups bonded to R.sup.2 or R.sup.4, which may be the same or different, and at least one of R.sup.1 and R.sup.5 is an organic group having 1 to 8 carbon atoms wherein one or more hydrogen atoms of the organic group is substituted with a cyano group.

A super-lubricity water lubricating additive, a super-lubricity water lubricant, a preparation method and application, wherein the additive is of a hollow spherical shell structure which includes at least one layer of spherical shell; the spherical shell sequentially includes a first polydopamine layer, a nanoparticle layer, a second polydopamine layer and an oxidized graphene layer from inside to outside, or a first polydopamine layer, a nanoparticle layer, a second polydopamine layer, a graphene layer and a third polydopamine layer from inside to outside; and nanoparticles of the nanoparticle layer are nano diamond, nano molybdenum disulfide or nano tungsten disulfide. The additive is prepared into a uniform aqueous solution to obtain the super-lubricity water lubricant. The additive can be easily adsorbed on a dual surface, and the nanoparticles released in a friction process cooperate with spherical oxidized graphene or graphene to form rolling friction so as to reduce frictional abrasion.

Provided is an entry sheet for drilling that, compared with a conventional entry sheet for drilling, has better hole position accuracy, can suppress drill bit breakage, and exhibits less processing chips wrapping around the drill bit. This entry sheet for drilling includes a metallic support foil and a layer comprising a resin composition that is formed on at least one surface of the metallic support foil, wherein the resin composition contains a cellulose derivative (A) and a water-soluble resin (B), the cellulose derivative (A) includes a hydroxyalkyl cellulose and/or a carboxyalkyl cellulose having a weight average molecular weight of 20,000 to 350,000, and based on 100 parts by mass of the resin composition, the content of the cellulose derivative (A) is 5 to 40 parts by mass and the content of the water-soluble resin (B) is 60 to 95 parts by mass.

The invention provides a fullerene compound; a lubricant that is for a magnetic recording medium and that contains the fullerene compound; and a magnetic recording medium. The fullerene compound is an ionic liquid that is represented by general formula (1) and is formed from a Bronsted acid (H.sub.n1X) and a Bronsted base ([R.sub.2R.sub.3)N—].sub.m1—R.sub.1); wherein one of the Brønsted acid and the Broønsted base contains a group having a fullerene; and the other contains a perfluoroalkyl chain. ##STR00001##

Disclosed is a lubricating oil composition for low-friction sliding materials, which is used in a sliding mechanism where a DLC film containing hydrogen in an amount of from 5 atom % to 50 atom % is formed on at least one sliding surface. The lubricating oil composition contains, in the lubricant base oil therein and based on the total amount of the composition, (A) an organic zinc dithiophosphate in an amount of from 0.005% by mass to 0.12% by mass in terms of the phosphorus concentration therein, (B) an amine-based friction-reducing agent in an amount of from 0.05% by mass to 5.0% by mass, and (C) an alkaline earth metal salicylate-based detergent and/or an alkaline earth metal sulfonate-based detergent in an amount of from 0.05% by mass to 0.5% by mass in terms of the alkaline earth metal concentration therein, wherein the component (A) contains, based on the total amount of the composition, a zinc primary dialkyldithiophosphate in an amount of from 0.005% by mass to 0.05% by mass in terms of the phosphorus concentration therein.

A fluorine-containing ether compound represented by Formula (1) is provided.
R.sup.1—R.sup.2—CH.sub.2—R.sup.3—CH.sub.2—R.sup.4—R.sup.5   (1)
(In Formula (1), R.sup.1 and R.sup.5 each represents a group having a heterocyclic ring and may be the same as or different from each other, R.sup.2 and R.sup.4 each represents a divalent linking group having a polar group and play be the same as or different from each other, and R.sup.3 represents a perfluoropolyether chain.)

Disclosed herein is a sliding member for an internal-combustion engine of an automobile or the like. The sliding member has excellent sliding properties due to high oleophilicity of its sliding surface achieved by adjusting the surface texture of a resin layer forming the sliding surface, which makes it possible to effectively prevent wear or seizure of the sliding member and a counterpart sliding member thereof. The sliding member includes a resin layer provided on a surface of a base material, in which the resin layer has a surface roughness of 1.05 or more, preferably 1.07 or more. The mean spacing (s) between local peaks of the resin layer may be in the range of 2 μm or more but 12 μm or less, but may be preferably in the range of 2 μm or more but 10 μm or less. Further, the mean height (Rc) of the resin layer may be in the range of 0.5 μm or more but 5.0 μm or less, but may be preferably in the range of 0.5 μm or more but 3.0 μm or less.

Disclosed is a fluoropolyether compound comprising a C.sub.4-10 aliphatic hydrocarbon chain present in the middle of the fluoropolyether compound and at least two perfluoropolyethers.

A sliding member includes: a lining layer formed from an alloy having a predetermined shape; and an overlay layer formed on an inner circumferential surface of the lining layer, the overlay layer being formed of a resin, the overlay layer sliding with a shaft, the overlay layer including a raised portion a height of which in a predetermined area including each of an edge in an axial direction of the shaft is greater than a height of another area of the overlay layer.

[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.