Aqueous Coating for Low Surface Energy Substrate Wetting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional solvent-based coating systems for low surface energy substrates face challenges such as high VOC emissions, environmental concerns, and limited compatibility with aqueous fluoropolymers, making it difficult to achieve stable and fast wetting without compromising performance.
Innovation Solution
An aqueous delivery system comprising a surfactant and a water-insoluble alcohol wetting agent, optionally with stabilizers and functional additives, is used to effectively wet and coat low surface energy substrates like microporous polytetrafluoroethylene, reducing the need for volatile organic compounds (VOCs) and enhancing the compatibility with a range of materials.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional solvent-based coating systems are used to coat low surface energy substrates, then wetting performance is improved, but VOC emissions increase and environmental compatibility deteriorates
Solution Approach 1:
The patent changes the fundamental parameter of the coating system from solvent-based to water-based, achieving wetting of low surface energy substrates through a water-insoluble alcohol component while eliminating VOC emissions. This parameter change transforms the harmful solvent-based system into an environmentally friendly aqueous system that maintains effective wetting performance.
Solution Approach 2:
The water-insoluble alcohol acts as an intermediary component that enables wetting of low surface energy substrates without requiring volatile organic solvents. This intermediary substance provides the necessary wetting functionality while the aqueous base carries the coating formulation, resolving the contradiction between effective wetting and VOC reduction.
2Object-affected harmful factors
If aqueous coating systems are used to reduce VOC emissions, then environmental compatibility is improved, but wetting capability on low surface energy substrates deteriorates
Solution Approach 1:
The patent creates a composite aqueous coating system combining water, surfactants, and water-insoluble alcohol components. This composite formulation leverages the synergistic effects of multiple ingredients to achieve wetting capability on low surface energy substrates while maintaining an aqueous base that eliminates VOC emissions.
Solution Approach 2:
The water-insoluble alcohol serves as a key intermediary that bridges the gap between aqueous systems and low surface energy substrates, enabling effective wetting without compromising the environmental benefits of water-based formulations.
3Stability of the object's composition
If high surfactant concentrations are used in emulsion systems, then stability against coalescence is improved, but compatibility with low surface energy substrates deteriorates
Solution Approach 1:
The water-insoluble alcohol acts as a mediating component that improves substrate compatibility without compromising emulsion stability. This intermediary substance enables the system to work effectively with low surface energy substrates while the surfactant maintains the necessary emulsion stability during storage and application.
Solution Approach 2:
The patent develops a composite formulation where surfactants and water-insoluble alcohols work synergistically. The surfactant provides emulsion stability while the alcohol component provides substrate compatibility, creating a balanced system that achieves both objectives simultaneously.
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 system provides a robust, stable, and environmentally friendly coating solution that enables efficient wetting and delivery of organic and inorganic materials to low surface energy substrates, maintaining substrate flexibility and breathability while reducing VOC emissions.
Implementation Method 1
Conventional aqueous micellar delivery systems have been used predominantly in the pharmaceutical industry... A micellar solution is one that contains at least one surfactant at a concentration greater than the critical micelle concentration
Implementation Method 2
when a hydrophobic or less water soluble material such as an oil is emulsified in the micellar solution, an emulsion results
Implementation Method 3
In order for a latex to spread across the substrate surface and form a uniform coating, it is necessary for it to 'wet' the substrate to which it is applied. 'Wetting' results when the contact angle, θ, between the aqueous latex and the solid substrate is less than about 90 degrees
Implementation Method 4
In order for a latex to spread across the substrate surface and form a uniform coating, it is necessary for it to 'wet' the substrate to which it is applied. 'Wetting' results when the contact angle, θ, between the aqueous latex and the solid substrate is less than about 90 degrees. Spontaneous wetting occurs when the surface energy between the solid and liquid, γSL is less than the surface energy between the solid and air, γSA
Implementation Method 5
Expanded microporous, liquid waterproof polytetrafluoroethylene materials... are especially well suited for this purpose. The expanded PTFE materials are liquid waterproof, but allow water vapor, in the form of perspiration, to pass through
Data Source
AI summary
An aqueous delivery system is described including at least one surfactant and at least one water insoluble wetting agent. Further described are low surface energy substrates, such as microporous polytetrafluoroethylene, coated with such an aqueous solution so as to impart a change in at least one surface characteristic compared to the surface characteristics of the uncoated low surface energy substrate.