Water-borne Coating Formulation pH Stability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing dispersion paints have limited storage stability and pH stability over time, failing to meet the requirements of commercial customers who need stability for at least six months without discoloration or contamination.

Innovation Solution

A water-borne dispersion coating formulation with a pH range of 10.0 to 12.5, comprising a polymeric organic binder, rheology modifier, dispersing agent, pigment/filler, and alkali hydroxide, with minimal residual monomer content and no organic in-can preservatives, allowing for extended storage stability without the need for water glass or silica sol.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If preservative-free dispersion paint is formulated with high pH (10-12) and alkali metal alkylsiliconates, then storage stability against contamination is improved, but storage time is limited to several weeks only

Engineering Contradiction:
Improvestorage stabilityVSAvoidstorage time
Core Design Contradiction:
ReliabilityVSDuration of action of stationary object

Solution Approach 1:

The patent changes the chemical parameters of the system by replacing alkali metal alkylsiliconates with a combination of aqueous polymer dispersion and alkali hydroxide, maintaining pH 10-12 while achieving extended storage stability beyond several weeks

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent uses a composite approach by combining aqueous polymer dispersion with alkali hydroxide to create a preservative-free system that maintains both high pH and long-term storage stability, overcoming the limitations of single-component systems

Inventive Principle:
Principle #40Composite materials

2Object-affected harmful factors

If conventional paint preservatives (CIT and MIT) are reduced or eliminated, then ecological aspects and allergenic compound reduction are improved, but storage stability over long periods deteriorates

Engineering Contradiction:
Improveallergenic compoundsVSAvoidstorage stability
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent extracts and eliminates conventional preservatives (CIT and MIT) from the formulation, replacing them with a preservative-free system based on aqueous polymer dispersion and alkali hydroxide that maintains storage stability without allergenic compounds

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent introduces aqueous polymer dispersion as an intermediary substance that mediates between the need for preservative-free formulation and the requirement for long-term storage stability, enabling the system to function without conventional preservatives

Inventive Principle:
Principle #24Intermediary (Mediator)

3Stability of the object's composition

If pH value is maintained in range of 10 to 12 using conventional methods, then storage stability is improved, but pH remains stable only over several weeks

Engineering Contradiction:
ImprovepH stabilityVSAvoidstability period
Core Design Contradiction:
Stability of the object's compositionVSDuration of action of stationary object

Solution Approach 1:

The patent changes the pH maintenance mechanism by using alkali hydroxide instead of alkali metal alkylsiliconates, enabling pH stability to be maintained over extended periods beyond several weeks while keeping pH in the 10-12 range

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP3456787B1Water-borne coating formulation
Publication Date: 2021.06.23 DAW SE

AI summary

The present invention is about a water-borne coating formulation having a pH in the range of 10,0 to 12,5 and comprising a polymeric organic binder based on an aqueous polymer dispersion a), a rheology modifier, a dispersing or wetting agent, a pigment or filler, and a base, and obtained by providing said dispersion a) having a residual (co)monomer content below 0,01 wt.-%, and wherein said dispersion a) is essentially free of any organic in-can preservatives. Further the present invention is about a method for the preparation of a water-borne coating formulation comprising the step of mixing an aqueous polymer dispersion A) with an aqueous matrix material B) comprising a pigment or filler and a base, wherein said dispersion A) has a residual (co)monomer content below 0,01 wt.-%. Moreover, the invention relates to the use of the water-borne coating formulation according to the invention for coating interior walls or ceilings.