Lubricating oil composition for spark-ignition internal combustion engine

Patent metadata

Field	Value
Publication number	US-2016304802-A1
Application number	US-201415038662-A
Country	US
Kind code	A1
Filing date	Nov 25, 2014
Priority date	Nov 25, 2013
Publication date	Oct 20, 2016
Grant date	—

Abstract

The lubricating oil composition for spark-ignition internal combustion engine according to the present invention is a lubricating oil composition to be used for a spark-ignition internal combustion engine including a piston having a piston ring, in which a total tension per piston of tensions applied to the piston ring is 30 N or less, the lubricating oil composition being a lubricating oil composition comprising a base oil, (A) an organic metal-based additive containing an alkali metal and/or an alkaline earth metal, and (B) an organic zinc-based additive, wherein a concentration of the component (A) on a basis of the total amount of the lubricating oil composition is 0.15% by mass or less as converted into a metal content; a concentration of the component (B) on a basis of the total amount of the lubricating oil composition is 0.15% by mass or less as converted into a zinc content; the product of the concentration (% by mass) of the component (A) and a base number (mgKOH/g) of the lubricating oil composition is 1.3 or less; the product of the concentration (% by mass) of the component (B) and an acid number (mgKOH/g) of the lubricating oil composition is 1.2 or less; and the lubricating oil composition has a Noack evaporation loss of 10% by mass or more and a kinematic viscosity at 100° C. of 9.3 mm 2 /s or less. The lubricating oil composition for spark-ignition internal combustion engine according to the present invention is capable of preventing a deterioration of the combustion state of a spark-ignition internal combustion engine.

First claim

1 . A lubricating oil composition for spark-ignition internal combustion engine that is a lubricating oil composition to be used for a spark-ignition internal combustion engine comprising a piston having a piston ring, in which a total tension per piston of tensions applied to the piston ring is 30 N or less, the lubricating oil composition being a lubricating oil composition comprising:
a base oil, (A) an organic metal-based additive containing an alkali metal and/or an alkaline earth metal, and (B) an organic zinc-based additive, wherein a concentration of the component (A) on a basis of the total amount of the lubricating oil composition is 0.15% by mass or less as converted into a metal content; a concentration of the component (B) on a basis of the total amount of the lubricating oil composition is 0.15% by mass or less as converted into a zinc content; the product of the concentration (% by mass) of the component (A) and a base number (mgKOH/g) of the lubricating oil composition is 1.3 or less; the product of the concentration (% by mass) of the component (B) and an acid number (mgKOH/g) of the lubricating oil composition is 1.2 or less; and the lubricating oil composition has a Noack evaporation loss of 10% by mass or more and a kinematic viscosity at 100° C. of 9.3 mm 2 /s or less.

2 . The lubricating oil composition for spark-ignition internal combustion engine according to claim 1 , further comprising an ashless base number improver having a base number of 1 mgKOH/g or more and 200 mgKOH/g or less on a basis of the total amount of the lubricating oil composition in an amount of 0.01% by mass or more as converted into a nitrogen content.

3 . The lubricating oil composition for spark-ignition internal combustion engine according to claim 1 , wherein the component (A) is a metal-based detergent having a base number of 10 mgKOH/g or more and 600 mgKOH/g or less.

4 . The lubricating oil composition for spark-ignition internal combustion engine according to claim 1 , wherein the component (B) is a zinc dialkyldithiophosphate and/or a zinc dialkyldioxyphosphate.

5 . The lubricating oil composition for spark-ignition internal combustion engine according to claim 1 , further comprising an organic molybdenum-based additive, a content of the organic molybdenum-based additive on a basis of the total amount of the lubricating oil composition being 0.01% by mass or more and 0.07% by mass or less as converted into a molybdenum content.

6 . The lubricating oil composition for spark-ignition internal combustion engine according to claim 1 any of claims 1 to 5 , wherein the spark-ignition internal combustion engine is a gasoline engine.

7 . A method for producing a lubricating oil composition for spark-ignition internal combustion engine that is a lubricating oil composition to be used for a spark-ignition internal combustion engine comprising a piston having a piston ring, in which a total tension per piston of tensions applied to the piston ring is 30 N or less, the method comprising:
blending a base oil with
(A) an organic metal-based additive containing an alkali metal and/or an alkaline earth metal and
(B) an organic zinc-based additive in such a manner that
a concentration of the component (A) on a basis of the total amount of the lubricating oil composition is 0.15% by mass or less as converted into a metal content; a concentration of the component (B) on a basis of the total amount of the lubricating oil composition is 0.15% by mass or less as converted into a zinc content; the product of the concentration (% by mass) of the component (A) and a base number (mgKOH/g) of the lubricating oil composition is 1.3 or less; the product of the concentration (% by mass) of the component (B) and an acid number (mgKOH/g) of the lubricating oil composition is 1.2 or less; and the lubricating oil composition has a Noack evaporation loss of 10% by mass or more and a kinematic viscosity at 100° C. of 9.3 mm 2 /s or less.

8 . A composition comprising:
a base oil, (A) an organic metal-based additive containing an alkali metal and/or an alkaline earth metal, and (B) an organic zinc-based additive, wherein a concentration of the component (A) on a basis of the total amount of the composition is 0.15% by mass or less as converted into a metal content; a concentration of the component (B) on a basis of the total amount of composition is 0.15% by mass or less as converted into a zinc content; the product of the concentration (% by mass) of the component (A) and a base number (mgKOH/g) of the composition is 1.3 or less; the product of the concentration (% by mass) of the component (B) and an acid number (mgKOH/g) of the composition is 1.2 or less; and the composition has a Noack evaporation loss of 10% by mass or more and a kinematic viscosity at 100° C. of 9.3 mm 2 /s or less.

Assignees

• Idemitsu Kosan Co

Inventors

• Tamura Kazushi
• Utaka Toshimasa
• Kamano Hideki
• Iijima Akira

Classifications

• C10M2229/02

  Unspecified siloxanes; Silicones · CPC title

• C10M2223/045

  Metal containing thio derivatives · CPC title

• C10N2030/52

  Base number [TBN] · CPC title

• C10M163/00 Primary

  Lubricating compositions characterised by the additive being a mixture of a compound of unknown or incompletely defined constitution and a non-macromolecular compound, each of these compounds being essential · CPC title

• C10N2040/255

  Gasoline engines · CPC title