UV roller coating technology has become the core process of metal surface treatment due to its high-efficiency curing, environmental protection and low consumption. This technology triggers the polymerization of photosensitive substances by ultraviolet rays to form a high-hardness and weather-resistant coating on the metal substrate. It is widely used in electronics, automobiles, packaging and other fields. This article will deeply analyze the process principle, material selection and innovative product application of UV roller coating.
1. Technical principles and core advantages
UV curing mechanism
Photochemical reaction: UV light source (mercury lamp/deuterium lamp) excites photoinitiator to produce free radicals or cations, triggering polymerization of resin monomers to achieve curing in seconds.
Equipment composition: coating roller evenly applies UV material, light curing device accurately controls energy, and conveying system ensures efficient flow of workpieces.
Core advantages
Environmental protection: 100% solid content formula, zero VOC emissions, in line with the trend of green manufacturing.
Coating quality: coating roller precisely controls thickness to achieve ±2μm uniformity, improving metal corrosion resistance and decorativeness.
Applicability: supports 3D curved surface coating, solving the coating problem of complex metal parts (such as automotive parts and electronic housings).
2. Selection and application of key materials
UV metal ink
Classification and performance:
Anti-counterfeiting ink (such as Mingbo UVMI-20 series): suitable for stainless steel and aluminum alloy, with adhesion of 5B (100 grid test).
High temperature resistant ink (UV-MI-28 series): temperature resistance > 200℃, used for high temperature parts such as automobile exhaust pipes.
Prepress treatment: metal surface needs to be degreased and phosphated to improve ink adhesion.
Adhesive and pressure-sensitive adhesive
Adhesive selection:
Double coating structure: base adhesive (such as CH205) enhances metal adhesion, and top adhesive (such as CH220) provides a wear-resistant barrier.
Environmentally friendly water-based adhesive (such as CH6100): no heavy metals, meet the requirements of food packaging cans.
UV pressure-sensitive adhesive:
Quick curing (<10 seconds), used for electronic component packaging and metal label pasting, weather resistance > 5 years.
Innovative resin materials
Shenzhen U-Sunny T-7131 UV resin:
Low shrinkage characteristics: curing shrinkage rate <5%, avoiding coating deformation and cracking, and improving dimensional stability.
Excellent adhesion: Adhesion to metal/glass substrates reaches 4H (pencil hardness), no coupling agent required.
Weather resistance: No peeling after immersion in boiling water for 48 hours, suitable for outdoor metal structures.
3. Industry application cases
Electronic industry
Circuit board coating: UV roller coating is resistant to solder and migration, and improves PCB stability.
Metal shell decoration: T-7131 resin + metal effect ink to achieve the mirror effect of iPhone middle frame.
Automobile manufacturing
Parts protection: UV coating is used for aluminum alloy wheels and fuel tank caps, and is resistant to salt spray for more than 1000 hours.
Interior bonding: UV pressure-sensitive adhesive fixes the metal trim of the dashboard, which is shock-resistant and high-temperature resistant.
Packaging industry
Metal can printing: UV ink (such as ALCHEMY Gold) achieves a high-gloss gold effect and is scratch-resistant.
4. Market trends and technological innovation
Demand for high-performance resins is rising: low-shrinkage, high-flexibility resins (such as T-7131) have an annual growth rate of 12%.
Green process upgrade: water-based UV coatings replace solvent-based ones to reduce carbon emissions.
3D coating technology: New UV coatings are compatible with spray systems to achieve full coverage of special-shaped metal parts.
UV roller coating technology is driving metal surface treatment towards high efficiency, environmental protection and multifunctionality. Shenzhen U-Sunny's T-7131 resin provides reliable solutions for high-end manufacturing with its core advantages of low shrinkage and strong adhesion. With breakthroughs in bio-based UV materials and nano-composite technology, this field will continue to release innovation potential.