Modified Carbon Black for Waterborne Coatings

Solution Overview

Problem

Current methods for dispersing carbon blacks in aqueous systems require high energy milling, which can damage the waterborne latex emulsion and result in coatings with poor hiding properties, and often necessitate excessive treatment and dispersant levels, increasing costs and complexity.

Innovation Solution

A low-energy stir-in process is used to disperse modified carbon blacks with specific surface treatments and dispersant concentrations in an aqueous vehicle, eliminating the need for high-energy milling and reducing the amount of treatment and dispersant required, while maintaining high hiding power and stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If high energy milling is used to disperse carbon blacks in aqueous systems, then dispersion stability is improved, but the waterborne latex emulsion is damaged and coating hiding properties deteriorate

Engineering Contradiction:

Improvedispersion stabilityVSAvoidhiding power

Core Design Contradiction:

Stability of the object's compositionVSReliability

Solution Approach 1:

The patent changes the surface area parameter of carbon black particles through controlled milling to achieve optimal dispersion stability without excessive energy input. By controlling the millbase particle size within specific ranges (e.g., 0.1-10 μm), the patent achieves stable dispersions that maintain hiding power while avoiding emulsion damage from over-milling.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent introduces dispersants as intermediary substances that mediate between carbon black particles and the aqueous latex emulsion. These dispersants prevent agglomeration and improve dispersion stability without requiring high-energy milling, thereby protecting the emulsion structure and maintaining coating hiding properties.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Stability of the object's composition

If excessive treatment and dispersant levels are used to improve dispersibility, then dispersion stability is improved, but costs and process complexity increase

Engineering Contradiction:

Improvedispersion stabilityVSAvoidprocess complexity

Core Design Contradiction:

Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The patent optimizes the surface area parameter of carbon black particles through controlled milling to achieve optimal dispersion stability without excessive energy input. By controlling the millbase particle size within specific ranges (e.g., 0.1-10 μm), the patent achieves stable dispersions that maintain hiding power while avoiding emulsion damage from over-milling.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent introduces dispersants as intermediary substances that mediate between carbon black particles and the aqueous latex emulsion. These dispersants prevent agglomeration and improve dispersion stability without requiring high-energy milling, thereby protecting the emulsion structure and maintaining coating hiding properties.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Stability of the object's composition

If high energy milling is used to achieve stable dispersion, then dispersion stability is improved, but energy consumption increases

Engineering Contradiction:

Improvedispersion stabilityVSAvoidenergy consumption

Core Design Contradiction:

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

Solution Approach 1:

The patent changes the surface area parameter of carbon black particles through controlled milling to achieve optimal dispersion stability without excessive energy input. By controlling the millbase particle size within specific ranges (e.g., 0.1-10 μm), the patent achieves stable dispersions that maintain hiding power while avoiding emulsion damage from over-milling.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent introduces dispersants as intermediary substances that mediate between carbon black particles and the aqueous latex emulsion. These dispersants prevent agglomeration and improve dispersion stability without requiring high-energy milling, thereby protecting the emulsion structure and maintaining coating hiding properties.

Inventive Principle:

Principle #24Intermediary (Mediator)

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 process achieves stable dispersion of carbon blacks at higher loadings with lower viscosities, allowing for more control over coating components and improved hiding power and color characteristics, reducing energy consumption and costs.

Implementation Method 1

the modified carbon black modified with a treating agent comprising an organic group and an ionic or ionizable group at a treating agent concentration of between 1.5 and 3.0 μmol/m2

Methodology Applied

Scientific EffectAdsorption: Adsorption

Implementation Method 2

a dispersant concentration of less than 2.0 mg per square meter of carbon black surface area as measured by STSA prior to treatment

Methodology Applied

Scientific EffectSurfactant action: Surfactant

Data Source

PatentUS9803099B2Carbon black for waterborne coatings

Publication Date: 2017.10.31 CABOT CORP

AI summary

An aqueous carbon black millbase, an aqueous carbon black liquid coating, and a method of making the millbase and liquid coating are provided. The carbon blacks are modified carbon blacks that are engineered to be able to be stirred into an aqueous vehicle without high energy milling of the carbon black. The modified carbon blacks include low organic treatment levels and the millbase and liquid coating do not require large quantities of dispersant. The resulting coatings exhibit excellent viscosity, color, hiding power and stability.