Water-Based Rare Earth Sol for Ceramic Powder Dispersion

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional rare earth metal compound sols are organic-based, requiring explosion-proof apparatuses, leading to high manufacturing costs and particle aggregation issues, which complicates the uniform dispersion of rare earth metals in ceramic powders for advanced capacitors.

Innovation Solution

A water-based rare earth metal compound sol is developed, using carboxylic acids or carboxylates with at least three carbonyl groups, such as citric acid, to stabilize rare earth metal compounds in a range of 1.2 to 3 molar ratios, preventing aggregation and allowing for easy handling without explosion-proof requirements, and a method for manufacturing ceramic powders with uniform rare earth metal distribution.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If organic sol is used to prevent particle aggregation, then particle dispersion is improved, but safety requirements increase and manufacturing cost increases

Engineering Contradiction:
Improveparticle dispersionVSAvoidsafety risk
Core Design Contradiction:
Stability of the object's compositionVSObject-affected harmful factors

Solution Approach 1:

The patent changes the fundamental parameter of the solvent from organic to water-based, transforming the system from flammable to non-flammable while maintaining particle dispersion stability through the use of carboxylic acids or carboxylates with at least three carbonyl groups as stabilizing agents

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent employs water as the solvent base, which is inherently safe, inexpensive, and eliminates the need for expensive explosion-proof equipment and special safety infrastructure required for organic solvents

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

2Stability of the object's composition

If organic sol is used to prevent particle aggregation, then particle dispersion is improved, but manufacturing cost increases

Engineering Contradiction:
Improveparticle dispersionVSAvoidmanufacturing cost
Core Design Contradiction:
Stability of the object's compositionVSEase of manufacture

Solution Approach 1:

The patent replaces expensive organic solvents with water, which is freely available and eliminates the need for costly safety infrastructure, while using carboxylic acids or carboxylates as stabilizing agents that can be added in controlled amounts to achieve the desired particle dispersion

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

Solution Approach 2:

The patent changes the solvent parameter from organic to water-based, fundamentally altering the cost structure of the manufacturing process while maintaining effective particle dispersion through chemical stabilization mechanisms

Inventive Principle:
Principle #35Parameter changes

3Manufacturing precision

If subcomponents are made into small particles for uniform mixing, then mixing uniformity is improved, but particle aggregation increases

Engineering Contradiction:
Improvemixing uniformityVSAvoidparticle aggregation
Core Design Contradiction:
Manufacturing precisionVSStability of the object's composition

Solution Approach 1:

The patent introduces carboxylic acids or carboxylates with at least three carbonyl groups as intermediary stabilizing agents that adsorb onto the surface of fine rare earth metal particles, creating a protective barrier that prevents particle aggregation while maintaining the fine particle size necessary for uniform mixing

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent creates a composite system consisting of fine rare earth metal particles combined with carboxylic acid or carboxylate molecules, forming a stable colloidal suspension where the organic-inorganic composite structure prevents aggregation while maintaining particle dispersion

Inventive Principle:
Principle #40Composite materials

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 water-based sol prevents particle aggregation, reduces manufacturing costs, and enables uniform dispersion of rare earth metals in ceramic powders, enhancing the production efficiency and quality of ceramic materials for multilayer capacitors and electronic components.

Implementation Method 1

a carboxylic acid or a carboxylate which has at least three carbonyl groups... the molar ratio (carbonyl group/rare earth metal) of the carbonyl group to the rare earth metal is in the range of 1.2 to 3

Methodology Applied
Scientific EffectChelation: Chemical Bonding

Data Source

PatentUS8592491B2Water-based rare earth metal compound sol, manufacturing method thereof, and method for manufacturing ceramic powder using the same
Publication Date: 2013.11.26 MURATA MFG CO LTD

AI summary

A particulate subcomponent for a barium titanate dielectric is obtained from a sol in which a rare earth metal compound is dispersed in water. The rare earth metal compound includes a carboxylic acid having at least three carbonyl groups and at least one rare earth metal which can be Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu so that the molar ratio (carbonyl group/rare earth metal) is in the range of 1.2 to 3. A method of making the sol and a method of using the sol to make a ceramic powder is described.