Silicone Coating Material for Rain-Streak and Scratch Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing coating materials for metal sheets struggle with high reactivity, low storage stability, and fouling of heating apparatuses, while failing to effectively prevent rain-streak stains and ensure sufficient scratch resistance.
Innovation Solution
A coating material containing a silicone resin with a specific silanol group content and a three-dimensional crosslinked structure, applied with a flame treatment to enhance uniform hydrophilicity and scratch resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If organosilicate (methyl silicate or ethyl silicate) is used to hydrophilize the coating film surface, then water contact angle is reduced, but storage stability deteriorates and heating apparatus fouling increases
Solution Approach 1:
The patent changes the chemical structure parameter of the silane compound from simple organosilicates (methyl silicate, ethyl silicate) to cyclic alkoxysilanes with specific ring structures (5- or 6-membered rings containing Si and O). This structural parameter change reduces reactivity while maintaining hydrophilization capability, resolving the contradiction between rain-streak stain resistance and storage stability
Solution Approach 2:
The patent introduces aromatic groups (such as phenyl groups) into the cyclic alkoxysilane structure, creating local regions with different polarities. The aromatic groups provide hydrophobic character that balances the hydrophilic silanol groups, reducing overall reactivity and preventing heating apparatus fouling while maintaining surface hydrophilicity for stain resistance
2Reliability
If ethyl silicate is used to move to the surface side, then surface hydrophilicity is enhanced, but hydrolysis reaction is delayed and rain-streak stains occur before sufficient hydrophilization
Solution Approach 1:
The cyclic alkoxysilane compounds are pre-designed with hydrolyzable alkoxy groups that are positioned and structured to facilitate controlled hydrolysis. The cyclic structure maintains stability during storage but enables progressive hydrolysis upon coating application, providing preliminary preparation for rapid surface hydrophilization without premature reaction
Solution Approach 2:
The patent modifies the steric and electronic parameters of the silane compound by using cyclic structures with specific ring sizes (5- or 6-membered). This changes the hydrolysis kinetics parameter, enabling faster and more uniform hydrolysis compared to linear organosilicates, thus reducing the time delay before sufficient surface hydrophilization is achieved
3Stability of the object's composition
If methyl silicate is used with high resin compatibility, then coating uniformity is improved, but surface movement is inhibited and hydrophilicity enhancement is insufficient
Solution Approach 1:
The cyclic alkoxysilane structure creates local regions with different properties: the cyclic siloxane ring provides structural stability and compatibility with the resin matrix, while the peripheral alkoxy groups and potential aromatic substituents provide controlled reactivity and surface activity. This local differentiation resolves the contradiction between uniformity and hydrophilicity
Solution Approach 2:
The patent creates a composite structure within the silane compound itself, combining the stable cyclic siloxane core with reactive alkoxy side groups and optionally aromatic moieties. This molecular-level composite structure enables simultaneous achievement of coating uniformity (from the stable core) and surface hydrophilicity (from the reactive periphery)
4Reliability
If organosilicate is used to react with moisture in air, then silanol groups are produced on surface, but evaporation during curing causes heating apparatus fouling
Solution Approach 1:
The patent changes the molecular weight and structural complexity parameter by using cyclic alkoxysilanes with aromatic groups instead of simple organosilicates. This parameter change increases the boiling point and reduces vapor pressure, preventing evaporation during curing while maintaining the ability to react with moisture and form silanol groups for stain resistance
Solution Approach 2:
The patent converts the potential harm of evaporation into a benefit by designing molecules that are structured to remain in the coating film during curing. The cyclic structure with aromatic groups provides thermal stability that prevents fouling, while the alkoxy groups ensure adequate reactivity with moisture to produce the desired hydrophilic surface
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 coating material achieves high storage stability, prevents rain-streak stains, and provides enhanced scratch resistance without fouling heating apparatuses.
Implementation Method 1
organosilicate reacts with moisture or the like in the air to produce silanol groups or siloxane bonds on the surface of the coating film
Implementation Method 2
the surface of a coating film composed of the coating material is subjected to a flame treatment
Data Source
Figure 1A~1C
Figure 2A~2B
AI summary
The purpose of the present invention is to provide a coating material that is for a coated metal plate, that has high storage stability, that is less likely to contaminate a heating device, and that can be used to produce a coated metal plate having a surface on which rain streaks are less likely to occur and having high scratch resistance. The coating material contains a silicone resin including 5-50 mol% of a silanol group with respect to the total number of moles of Si atoms.