Abstract: A piston ring in which carbon films with film qualities optimized to be adapted to required performance are formed on an outer circumferential sliding surface and top and bottom surfaces thereof with good productivity is provided, and a high-performance engine which employs the piston ring is also provided. In the piston ring, a carbon film is formed on an outer circumferential sliding surface and top and bottom surfaces. The carbon film contains a stacking of at least two types of carbon film layers with different film qualities, and a thickness ratio of the two types of carbon film layers is different between the outer circumferential sliding surface and the top and bottom surfaces.

Abstract: Provided is a piston ring having excellent low-friction properties and abrasion resistance manufactured without the need for precision control using an ordinary film formation device that does not have a special function.

Abstract: Provided is a piston ring having excellent low-friction properties and abrasion resistance manufactured without the need for precision control using an ordinary film formation device that does not have a special function.

Abstract: A piston ring in which carbon films with film qualities optimized to be adapted to required performance are formed on an outer circumferential sliding surface and top and bottom surfaces thereof with good productivity is provided, and a high-performance engine which employs the piston ring is also provided. In the piston ring, a carbon film is formed on an outer circumferential sliding surface and top and bottom surfaces. The carbon film contains a stacking of at least two types of carbon film layers with different film qualities, and a thickness ratio of the two types of carbon film layers is different between the outer circumferential sliding surface and the top and bottom surfaces.

Abstract: 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.

Abstract: 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 amide-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.

Abstract: 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.

Abstract: 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 amide-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.

Abstract: A lubricant oil composition containing an organic molybdenum compound which contains at least either one of a nitrogen (N) atom and an oxygen (O) atom in the molecule thereof and which may optionally contain a sulfur (S) atom, wherein a sulfur content of the organic molybdenum compound is 0.5% by mass or less based on the organic molybdenum compound. The lubricant oil composition, when used as a lubricant oil for a low-friction sliding material, exhibits an extremely low friction coefficient. A sliding mechanism having excellent low-friction property and wear resistance can be provided by combining the lubricant oil composition and a sliding member having a DLC film on its sliding face.

Abstract: Provided by the present invention is a lubricating oil composition showing a very low frictional coefficient when used as a lubricating oil for a low friction sliding material prepared by blending with an additive selected from a specific phosphorus-zinc-containing compound and a specific sulfur-containing compound, and a sliding mechanism having an excellent low frictional property in which a DLC film containing 5 to 50 atom % of hydrogen is formed or a sliding mechanism having an excellent low frictional property in which 1 to 30 atom % of tungsten (W) or molybdenum (Mo) is contained is provided by combining the above lubricating oil composition with a sliding member having a film of a specific low frictional sliding material on a sliding face.

Abstract: Provided by the present invention is a lubricating oil composition showing, though containing ZnDTP as an abrasion resistant agent, a low friction coefficient when used as a lubricating oil for a low friction sliding material, that is, a specific lubricating oil composition which is prepared by blending a lubricant base oil with (A) a specific alkali earth metal-containing cleaning agent, (B) a specific boron-non-containing succinimide base ashless dispersant, (C) a zinc dialkyldithiophosphate and (D) a specific sulfur base compound and which is used for a low friction sliding material.

Abstract: A metal casing for a semiconductor device is manufactured by a powder metallurgy injection molding process which uses infiltration. The metal casing includes a base member and an enclosure member arranged on the base member. The base member and the enclosure member are formed of an alloy including 20 to 50 percent by volume of copper, equal to or less than 1 percent by weight of nickel and remainder of tungsten or molybdenum. The metal casing is manufactured as a net-shape product by a process which includes the steps of mixing tungsten powder and nickel powder having average particles sizes equal to or less than 40 .mu.