Calcium Complex Grease Composition with Behenic Acid

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing grease compositions face challenges in achieving superior shear stability, long bearing life, thermal stability, and good low-temperature flow characteristics, particularly with lithium soap-based greases that are prone to softening at high temperatures and urea greases that use toxic substances, and there is a need for materials with stable supplies and environmental compatibility.

Innovation Solution

A calcium complex grease composition using C18-22 straight-chain higher fatty acids, aromatic monocarboxylic acids, and C2-4 straight-chain saturated lower fatty acids, with behenic acid making up 25-70% of the higher fatty acids, to create a stable lubricating function over a broad temperature range.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If stearic acid is used for the higher fatty acid constituent to achieve heat resistance, then dropping point is improved, but bearing life deteriorates due to softening at high temperatures

Engineering Contradiction:
Improvedropping pointVSAvoidbearing life
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

The invention changes the chemical composition parameters by specifying behenic acid content at 25-70 mass% of higher fatty acids, replacing conventional stearic acid-based formulations. This parameter change achieves both high dropping point (>260°C) and improved bearing life by creating a calcium complex soap with optimal molecular structure that resists softening at high temperatures.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention uses a composite fatty acid system combining multiple higher fatty acids with behenic acid as the primary component (25-70 mass%). This composite approach creates a calcium complex soap that leverages the synergistic effects of different fatty acid chains, achieving superior thermal stability and bearing life compared to single-component systems.

Inventive Principle:
Principle #40Composite materials

2Duration of action of moving object

If bearing life is extended by adjusting grease composition, then lubrication durability is improved, but low-temperature flow characteristics deteriorate

Engineering Contradiction:
Improvebearing lifeVSAvoidlow-temperature flow characteristics
Core Design Contradiction:
Duration of action of moving objectVSEase of operation

Solution Approach 1:

The invention optimizes the fatty acid chain length parameter by using C18-C22 higher fatty acids with behenic acid (C22) as the dominant component. This specific chain length range creates a calcium complex soap that maintains appropriate viscosity and flow characteristics at low temperatures while providing extended bearing life through enhanced thermal and oxidative stability.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention applies different fatty acid components with specific properties to different functional requirements: behenic acid provides thermal stability and bearing life, while the presence of other higher fatty acids (stearic acid, oleic acid, 12-hydroxystearic acid) ensures low-temperature flow characteristics. This local optimization of composition achieves both contradictory requirements simultaneously.

Inventive Principle:
Principle #3Local quality

3Adaptability or versatility

If lithium complexes are used to broaden usable temperature domain, then temperature range is improved, but supply stability deteriorates due to rising lithium demand

Engineering Contradiction:
Improveusable temperature domainVSAvoidsupply stability
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The invention extracts the grease-forming capability from lithium-based systems and transfers it to calcium-based systems. By using calcium hydroxide to form calcium complex soaps from higher fatty acids, the invention achieves comparable or superior temperature domain performance without dependence on lithium supply, thereby ensuring stable and sustainable material availability.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention replaces expensive and supply-constrained lithium materials with abundant and cost-effective calcium materials. Calcium hydroxide and higher fatty acids are readily available, inexpensive raw materials that do not suffer from the supply uncertainties and price volatility affecting lithium, making the grease composition economically and logistically more sustainable.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

4Temperature

If urea greases are used for heat resistance, then temperature resistance is improved, but environmental compatibility deteriorates due to toxic substances

Engineering Contradiction:
Improveheat resistanceVSAvoidenvironmental compatibility
Core Design Contradiction:
TemperatureVSObject-affected harmful factors

Solution Approach 1:

The invention converts the traditional approach of using toxic substances (urea and its derivatives) for heat resistance into a beneficial system using naturally occurring, non-toxic higher fatty acids and calcium hydroxide. The calcium complex soap formulation achieves equal or superior heat resistance (>260°C dropping point) while eliminating environmental and health hazards associated with urea-based greases.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The invention changes the chemical basis of heat-resistant greases from nitrogen-containing urea compounds to oxygen-containing higher fatty acid calcium complexes. This parameter change in molecular structure eliminates toxicity while maintaining or enhancing thermal stability, oxidative resistance, and overall environmental compatibility of the grease composition.

Inventive Principle:
Principle #35Parameter changes

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 exhibits improved bearing life and low-temperature characteristics, maintaining stable lubrication functions across a broad temperature domain, enhancing the practical performance of greases in severe lubricating environments.

Implementation Method 1

a grease composition containing a base oil and, as a thickener a calcium complex soap

Methodology Applied
Scientific EffectIntermolecular forces:

Implementation Method 2

stable lubricating functions in a broad temperature domain

Methodology Applied
Scientific EffectLubrication: Lubrication

Data Source

PatentUS11198830B2Grease composition
Publication Date: 2021.12.14 SHELL USA INC

AI summary

The invention provides a grease composition, being a grease composition containing a base oil and, as a thickener a calcium complex soap, and being a grease composition using for the carboxylic acids forming the aforementioned calcium complex soap substituted or unsubstituted C18-22 straight-chain higher fatty acids, aromatic monocarboxylic aromatic acids having substituted or unsubstituted benzene rings and C2-4 straight-chain saturated lower fatty acids, wherein the aforementioned substituted or unsubstituted C18-22 straight-chain higher fatty acids include behenic acid and the amount of behenic acid used, as a mass ratio in terms of the total amount of the aforementioned substituted or unsubstituted C18-22 straight-chain higher fatty acids used, is from 25 mass % up to 70 mass %.