Glass substrates are one of the most challenging applications in the field of UV coating for glass adhesion due to their low surface energy and non-polar properties. Traditional UV coatings on glass often face problems such as poor adhesion, water boiling failure, laser engraving burrs, etc. - the internal stress caused by curing shrinkage, insufficient interface wettability, and insufficient post-processing tolerance are the main pain points.
Cationic UV curing technology has become a key technology to solve the problem of glass adhesion due to its unique chemical reaction mechanism:
Ultra-low shrinkage (<3%), significantly reducing the stress inside the coating and avoiding peeling due to stress concentration
Deep curing ability, not inhibited by oxygen, ensuring complete cross-linking inside the coating
Directional design of polar groups, forming strong hydrogen bonds or chemical bonds with the silicon hydroxyl groups on the glass surface
Resistant to wet and hot aging, epoxy groups provide excellent water resistance, passed the 100℃×1h water boiling test
1. U-9310 resin: an innovative solution for glass adhesion
U-9310 is designed to overcome the problem of glass adhesion. Its molecular structure integrates three core technologies:
Cationic epoxy skeleton: The main chain contains alicyclic epoxy groups. The ring-opening polymerization shrinkage rate during curing is only 2-3%, which is much lower than the free radical system (>10%), reducing interfacial stress from the source
Silane coupling module: The built-in alkoxysilane group (such as -Si(OCH₃)₃) condenses with the -Si-OH on the glass surface during the curing process to form a Si-O-Si covalent bond, making the adhesion reach level 0-1 (GB/T 9286 standard)
Hyperbranched structure: The dendritic molecular topology improves leveling, and the contact angle on the glass surface is <15°, achieving perfect micropore infiltration
2. Performance verification of four key application scenarios
The UV coating for glass adhesion solution based on U-9310 has been verified in multiple high-demand fields:
1. Electronic glass cover
Achieve 5B adhesion of vacuum aluminum layer on mobile phone cover through 16μm coating (ASTM D3359)
Hand sweat resistance test: 40℃/90%RH×240h without discoloration and delamination
2. Automotive glass trim
Passed 100 cycles of -40℃~85℃ hot and cold shock, no cracking of coating
Rain wiper friction resistance: 10,000 scratches (load 500g) without bottom exposure
3. Home appliance control panel
Support fine laser engraving: line width 0.1mm pattern edge without burrs (traditional coating ≥0.3mm)
Anti-cleaner wiping: 5% NaOH solution soaked for 8h without swelling
4. Packaging glass bottles
Pasteurization: After 30 minutes of 82℃ hot water spraying, the adhesion remains at level 0
Drop resistance: 500ml bottle dropped 1.5m without cracking of the coating
3. Technology extension: Innovative direction to break through traditional limitations
The performance of U-9310 in special scenarios can be further enhanced through compounding technology:
Dual curing system: Add 3%-5% free radical initiator (such as TPO) to achieve deep curing in the shadow area and solve the problem of insufficient curing at the edge of special-shaped glass parts
Toughening modification: Introduce aliphatic polyurethane acrylate (functionality 2-6) to make the coating elongation at break > 100%, suitable for bendable glass
High temperature resistance upgrade: Composite silicone resin (≤10%) to increase heat resistance to 180℃/1h, meeting the requirements of headlight glass.
Conclusion: Reshaping the future of glass surface treatment
UV coating for glass adhesion of glass substrates was once restricted by the bottleneck of adhesion. U-9310 cationic curing resin has achieved the following through molecular bonding design:
Glass adhesion "zero breakthrough" → 2h water boiling resistance without abnormality → Laser engraving accuracy reaches 0.1mm → Comprehensive cost reduction by 30%