Lubricating Oil Composition with Nitrogen Management Index

Solution Overview

Problem

Lubricating oils for internal combustion engines face challenges in achieving improved fuel efficiency and oxidative stability while maintaining a low amount of sulfated ash.

Innovation Solution

A lubricating oil composition combining specific components such as a lubricant base oil, molybdenum-based friction modifier, nitrogen-containing ashless friction modifier, succinimide or derivative as a dispersant, amine ashless antioxidant, and metallic detergent, with a nitrogen management index of 0.60 or less.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If friction modifiers are used to improve fuel efficiency, then fuel efficiency is improved, but oxidative stability deteriorates

Engineering Contradiction:

Improvefuel efficiencyVSAvoidoxidative stability

Core Design Contradiction:

Use of energy by moving objectVSStability of the object's composition

Solution Approach 1:

The patent applies parameter changes by precisely controlling the nitrogen management index (a composite parameter combining nitrogen content and sulfur content) to 0.80 or less, while also controlling sulfated ash content to 1.05 mass % or less. This dual parameter control enables the formulation to achieve both improved fuel efficiency through friction modification and maintained oxidative stability, resolving the contradiction between these two properties.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent uses a composite additive package containing multiple friction modifiers (including molybdenum-based and ashless types), antioxidants, and other additives in specific combinations. This composite formulation approach allows the lubricating oil to exhibit both low friction characteristics for fuel efficiency and high oxidative stability, as the different components work synergistically to address both requirements simultaneously.

Inventive Principle:

Principle #40Composite materials

2Use of energy by moving object

If friction modifiers are used to improve fuel efficiency, then fuel efficiency is improved, but sulfated ash content increases

Engineering Contradiction:

Improvefuel efficiencyVSAvoidsulfated ash content

Core Design Contradiction:

Use of energy by moving objectVSQuantity of substance

Solution Approach 1:

The patent applies parameter changes by precisely controlling the nitrogen management index (a composite parameter combining nitrogen content and sulfur content) to 0.80 or less, while also controlling sulfated ash content to 1.05 mass % or less. This dual parameter control enables the formulation to achieve both improved fuel efficiency through friction modification and maintained oxidative stability, resolving the contradiction between these two properties.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent employs ashless friction modifiers as part of the additive package, which provide friction reduction benefits without contributing to sulfated ash formation. This substitution of traditional ash-containing friction modifiers with ashless alternatives allows the maintenance of low sulfated ash content while preserving fuel efficiency improvements.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

3Stability of the object's composition

If oxidative stability is improved, then oxidative stability is improved, but fuel efficiency deteriorates

Engineering Contradiction:

Improveoxidative stabilityVSAvoidfuel efficiency

Core Design Contradiction:

Stability of the object's compositionVSUse of energy by moving object

Solution Approach 1:

The patent applies parameter changes by precisely controlling the nitrogen management index (a composite parameter combining nitrogen content and sulfur content) to 0.80 or less, while also controlling sulfated ash content to 1.05 mass % or less. This dual parameter control enables the formulation to achieve both improved fuel efficiency through friction modification and maintained oxidative stability, resolving the contradiction between these two properties.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent uses a composite additive package containing multiple friction modifiers (including molybdenum-based and ashless types), antioxidants, and other additives in specific combinations. This composite formulation approach allows the lubricating oil to exhibit both low friction characteristics for fuel efficiency and high oxidative stability, as the different components work synergistically to address both requirements simultaneously.

Inventive Principle:

Principle #40Composite materials

4Quantity of substance

If sulfated ash content is reduced, then sulfated ash content is reduced, but fuel efficiency deteriorates

Engineering Contradiction:

Improvesulfated ash contentVSAvoidfuel efficiency

Core Design Contradiction:

Quantity of substanceVSUse of energy by moving object

Solution Approach 1:

The patent applies parameter changes by precisely controlling the nitrogen management index (a composite parameter combining nitrogen content and sulfur content) to 0.80 or less, while also controlling sulfated ash content to 1.05 mass % or less. This dual parameter control enables the formulation to achieve both improved fuel efficiency through friction modification and maintained oxidative stability, resolving the contradiction between these two properties.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent employs ashless friction modifiers as part of the additive package, which provide friction reduction benefits without contributing to sulfated ash formation. This substitution of traditional ash-containing friction modifiers with ashless alternatives allows the maintenance of low sulfated ash content while preserving fuel efficiency improvements.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The composition achieves improved fuel efficiency and oxidative stability while maintaining a low amount of sulfated ash, as demonstrated by reduced increases in acid value and kinematic viscosity after NOx injection tests.

Implementation Method 1

a molybdenum-based friction modifier based on the total amount of the composition as an amount of molybdenum: 50 mass ppm to 2000 mass ppm

Methodology Applied

Scientific EffectBoundary lubrication: Lubrication

Implementation Method 2

a nitrogen-containing ashless friction modifier

Methodology Applied

Scientific EffectAdsorption: Adsorption

Implementation Method 3

a succinimide or a derivative thereof as a dispersant

Methodology Applied

Scientific EffectSteric hindrance:

Implementation Method 4

an amine ashless antioxidant as an antioxidant

Methodology Applied

Scientific EffectFree radical scavenging: Oxidation

Data Source

PatentUS12331262B2Lubricating oil composition for internal combustion engine

Publication Date: 2025.06.17 ENEOS CORP

AI summary

Provided is a lubricating oil composition for an internal combustion engine containing: (A) a lubricant base oil with a kinematic viscosity at 100° C. of 2.0 mm2/s to 5.0 mm2/s; (B) 50 mass ppm to 2000 mass ppm of a molybdenum-based friction modifier based on the total amount of the composition as an amount of molybdenum; (C) a nitrogen-containing ashless friction modifier; (D) a succinimide or a derivative thereof as a dispersant; (E) an amine ashless antioxidant as an antioxidant; and (F) 1000 mass ppm to 2200 mass ppm of a metallic detergent based on the total amount of the composition as an amount of metal, wherein the amount of sulfated ash in the composition is 0.9 mass % or less, and a nitrogen management index is 0.60 or less. Provided is a lubricating oil composition for an internal combustion engine having improved fuel efficiency and oxidative stability, while maintaining low amount of sulfated ash.