Acidic Aqueous Composition for Metallic Surface Treatment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for treating aluminum and aluminum alloy surfaces require multiple steps, are economically and ecologically disadvantageous due to the use of phosphonates and complex fluorides, and often fail to provide sufficient corrosion protection and adhesion properties.
Innovation Solution
A single-step method involving an acidic aqueous composition containing titanium, zirconium, or hafnium ions and a copolymer with specific side chains, which forms a conversion coating layer that enhances adhesion and reduces corrosive subsurface migration and filiform corrosion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional two-step methods are used (silane/siloxane treatment followed by phosphonate treatment), then adhesion properties and corrosion protection are improved, but processing time, energy consumption, and labor costs increase
Solution Approach 1:
The patent combines the functions of silane/siloxane treatment and phosphonate treatment into a single aqueous composition containing both metal complex fluorides and phosphonate compounds. This merging of multiple treatment steps into one simultaneous treatment achieves both adhesion promotion and corrosion protection without requiring sequential processing steps, thereby reducing processing time and labor costs while maintaining the reliability benefits of both treatments
Solution Approach 2:
The aqueous composition is designed to perform multiple functions simultaneously: it acts as both a silane/siloxane coupling agent and a phosphonate conversion coating former. The composition contains metal complex fluorides that form conversion coatings, phosphonate compounds that enhance adhesion and corrosion resistance, and optional silane/siloxane components, all working together in a single treatment step to achieve the combined benefits of what would otherwise require separate processing steps
2Reliability
If phosphonate compounds are used in aqueous solutions, then adhesion properties are improved, but ecological harm and wastewater treatment costs increase
Solution Approach 1:
The patent optimizes the concentration parameters of phosphonate compounds within specific ranges (0.1-10 g/L) and controls the pH value (2-6) to achieve effective adhesion promotion while minimizing ecological harm. By precisely controlling these parameters, the treatment achieves sufficient adhesion properties with reduced phosphonate usage, thereby lowering ecological contamination and wastewater treatment requirements compared to conventional high-concentration phosphonate treatments
3Reliability
If complex fluorides are used to form conversion coating, then adhesion properties are improved, but processing complexity and cost increase
Solution Approach 1:
The patent merges the conversion coating formation function of complex fluorides with the adhesion promotion function of phosphonate compounds into a single integrated aqueous composition. This eliminates the need for separate processing steps while maintaining the adhesion benefits of complex fluoride conversion coatings, thereby reducing processing complexity without sacrificing reliability
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 method achieves excellent adhesion and anti-corrosion properties without the need for phosphonates or chromium, reducing time, energy, and labor costs while eliminating harmful constituents, thus being both economically and ecologically advantageous.
Implementation Method 1
side chain (S1) comprises at least one functional group selected from the group consisting of hydroxyl groups and carboxylic acid groups and mixtures thereof
Implementation Method 2
side chain (S2) comprises at least two hydroxyl groups
Implementation Method 3
comprising (a) one or more metal ions selected from the group of titanium, zirconium and hafnium ions
Implementation Method 4
contacting said surface with an acidic aqueous composition (A)
Data Source
AI summary
Disclosed herein are a method for treatment of at least one metallic surface of a substrate including at least a step of contacting said surface with an acidic aqueous composition (A), said acidic aqueous composition (A) including (a) one or more metal ions selected from the group consisting of titanium, zirconium and hafnium ions (b) and one or more polymers (P) having side chains (S1) and (S2) being different from one another, where side chain (S1) includes at least one functional group selected from the group consisting of hydroxyl groups and carboxylic acid groups and mixtures thereof, and side chain (S2) includes at least two hydroxyl groups, a corresponding acidic aqueous composition (A) as such, a master batch to produce such acidic aqueous composition (A), the use of the acidic aqueous composition (A) for treating metallic surfaces and substrates including the thus treated surfaces.