UV coatings and UV adhesives in photovoltaics—characterized by higher efficiency, thinner and lighter designs, lower carbon footprints, and extended service life— are no longer merely auxiliary materials; they have become critical functional materials integral to the entire value chain, spanning from glass to solar cells, encapsulation, backsheet, and junction boxes.
The UV coating provides surface protection, light transmission enhancement, self-cleaning properties, and weather resistance, while the UV adhesive ensures low-temperature bonding, sealing and insulation, conductive interconnection, and structural reinforcement. Together, these two technologies are redefining the manufacturing efficiency, power generation yield, and 30-year outdoor reliability of photovoltaic modules.
I. Photovoltaic UV Coating: A Dual Protection System for Modules – Combining Optical Performance and Protective Capabilities
A UV coating is an ultra-thin functional film layer (typically 1–5 μm) applied via roller coating or spray coating onto the surfaces of photovoltaic glass, backsheet, frame, or solar cells, and then rapidly cured under ultraviolet (UV) light. It exhibits high light transmittance, UV resistance, anti-aging properties, hydrophobic self-cleaning capabilities, and high barrier performance, making it a core solution for enhancing the power generation efficiency and outdoor durability of photovoltaic modules.
1. Common Types of UV Coatings and Their Core Functions
① High-transmittance, UV-transparent coating (front side of photovoltaic glass)
Ingredients: silicon-modified acrylate/silicone resin + nano-SiO₂
Core Value: Visible light transmittance ≥91%, reduced surface reflectance, and increased module power by 1.5–2.5%
Features: UV-LED curing at 365/395 nm, temperature rise <15 °C, no damage to the glass substrate; high hardness, excellent abrasion resistance, and long-term resistance to yellowing.
② Self-cleaning and hydrophobic UV coating (front side of photovoltaic glass)
Ingredients: Organic polysilazane + triazine-based UV absorber
Core Values: Water contact angle ≥120°, automatic rainwater rinsing of dust, reduction of dust adhesion by ≥50%, decreased labor costs for cleaning, and sustained high light transmittance over extended periods.
Features: Full UVB-band shielding; no performance degradation after 1,000 hours of aging at 85 °C / 85 % RH; suitable for high-dust and high-humidity environments such as deserts and coastal regions.
③ Weather-and anti-aging UV coating (backsheet/frame)
Ingredients: fluorocarbon-modified acrylate, siloxane-hybrid resin
Core Values: Long-term resistance to UV aging, salt spray, and combined heat and humidity; the backsheet and frame remain free from yellowing, cracking, or delamination for 30 years.
Features: UV aging> 15,000 hours, gloss retention rate of 95% after 10 years; suitable for offshore photovoltaic applications and salt spray environments.
④ High-barrier UV coating (on the surface of HJT/perovskite cells)
Composition: polyimide–montmorillonite hybrid system + UV absorber
Core Value: WVTR ≤ 0.1 g/m²·day, UV transmittance <0.05%; protects the HJT amorphous silicon layer and perovskite active layer against moisture and UV erosion, thereby extending battery lifetime.
Features: ultra-thin and uniform thickness (0.5–2 μm), no thermal damage, and compatibility with high-sensitivity, high-efficiency batteries.
⑤ High-reflectivity UV coating (inner side of the backsheet)
Ingredients: Acrylate resin + rutile TiO₂
Core value: Visible light reflectance of 92–95%, enabling secondary utilization of light not absorbed by the cells, thereby increasing module power by 1–2%.
Features: wide-angle diffuse reflection, enhanced power generation in low-light environments, and compatibility with single-sided or bifacial modules.
2. Key Advantages of UV Coatings
✅ Low-temperature curing without thermal damage: Curing at room temperature or with low temperature ramp, making it suitable for thermosensitive substrates such as ultra-thin glass, perovskites, and HJT.
✅ Ultra-fast curing efficiency: Curing completed in 3–10 seconds, boosting production line speed by over 50% and increasing annual production capacity per line by over 300,000 pieces.
✅ Ultra-thin and uniform with controllable performance: the film layer is uniform without shading, and its optical and protective properties can be precisely tuned.
✅ Green and VOC-free: 100% solid content, no solvent emissions, complies with low-carbon manufacturing requirements for photovoltaic applications.
✅ Long-term durability: UV-resistant, resistant todamp heat and salt spray, enabling the modules to deliver stable power generation for 25–30 years.
II. Photovoltaic UV Adhesive: A “Versatile Bonding Agent” for Low-Temperature Adhesion and Sealing
UV adhesive is a single-component UV-curable adhesive that cures within seconds upon exposure to 365/395 nm UV light. In photovoltaic applications, it plays critical roles—including bonding of solder strips, sealing of frames, potting of junction boxes, bonding of glass to solar cells, and structural fixation—making it a next-generation green bonding solution to replace conventional high-temperature soldering and thermally cured epoxy/silicone adhesives.
1. Common Types of UV Adhesives and Their Typical Applications
① UV welding tape adhesive (cell-to-welding tape interconnection)
Ingredients: modified epoxy/polyurethane acrylate + silver powder / silver-plated copper powder conductive fillers + photoinitiator
Core Advantages: Low-temperature cold bonding (no high-temperature soldering), 2–10 seconds of curing time, elimination of thermal stress, and a reduction in cell hidden crack rate by>90%; compatible with high-efficiency cell types such as HJT, TOPCon, and BC, enabling the use of finer solder strips to minimize light shielding and thereby enhance conversion efficiency.
Performance: shear strength ≥ 18 MPa, low contact resistance, resistance to heat and humidity, and long-term stability at 85 °C/85% RH.
② UV-edge sealant (glass–aluminum alloy frame)
Ingredients: weather-resistant acrylate, silicone-modified epoxy acrylate
Core Features: Rapid curing at room temperature; sealed and waterproof (IP67), preventing the ingress of rainwater, moisture vapor, and dust; shear strength ≥ 19 MPa; resistant to extreme temperatures (-60 °C to 180 °C); accommodates thermal expansion and contraction to prevent frame detachment or deformation.
Features: solvent-free, resistant to yellowing, with a retention rate of ≥85% after 2,000 hours of outdoor aging.
③ UV potting compound for junction boxes (box body-to-backplate bonding + terminal insulation)
Ingredients: high-insulation acrylate, epoxy-modified resin
Core Values: A triple-function design integrating adhesion, insulation, and sealing; volume resistivity ≥ 10¹³ Ω·cm, ensuring protection against leakage current and short circuits; resistant to electrolyte corrosion, with no water leakage observed after 72 hours of 85 °C/85 % RHdamp heat testing, guaranteeing long-term stability of the junction box.
Features: rapid curing, high automation and encapsulation efficiency, and compatibility with a wide range of junction box structures.
④ UV glass bonding adhesive (film/perovskite modules)
Ingredients: High transparency, low yellowing acrylic ester
Core Value: Glass bonded to solar cells or thin films, with light transmittance ≥91%, UV resistance, and long-term resistance to yellowing; cures at room temperature to protect thermosensitive active layers, such as perovskites.
Features: Index-matching, low optical loss, and compatibility with both flexible and rigid thin-film modules.
⑤ UV structural fixing adhesive (component auxiliary material fixation + edge reinforcement)
Ingredients: High-toughness polyurethane acrylate
Core values: edge reinforcement of solar cells, backsheet fixation, and adhesive bonding of isolation strips; flexible and crack-resistant, with an elongation rate ≥200%, vibration resistance, and suitability for outdoor wind loads and thermal cycling.
2. Key Advantages of UV Adhesive
✅ Low-temperature process for high-efficiency cells: completely eliminates high-temperature welding and thermal curing, compatible with HJT, perovskite, and ultra-thin silicon wafers, delivering a yield increase of 2–3%.
✅ Instant curing, doubled production capacity: initial set in 5 seconds, full set in 30 seconds; cycle time reduced by over 80%, making it ideal for high-speed automated production lines.
✅ Green and low-carbon, zero VOC emissions: single-component, solvent-free formulation; no heating required; energy consumption reduced by over 90%, aligning with the dual-carbon goals.
✅ Balanced performance, engineered for 30 years of outdoor use: strong adhesion, excellent insulation, superior weather resistance, resistance to yellowing, and reliable waterproof sealing.
✅ Highly versatile and applicable across all scenarios: from cell interconnection to module encapsulation and auxiliary material fastening, it provides a one-stop solution for bonding and sealing requirements.
III. UV Coating + UV Adhesive: The Dual Engines for “Cost Reduction & Efficiency Enhancement + Quality Improvement & Service Life Extension” in the Photovoltaic Industry Chain
1. Manufacturing side: comprehensive optimization of efficiency, yield, and cost
Production cycle shortened by 50–80%, and single-line production capacity increased by 20–30%;
The hidden crack rate of solar cells has decreased by over 90%, while the yield rate has increased by 2–3%;
Energy consumption reduced by over 90%, zero VOC emissions, and lower environmental compliance costs;
It offers strong adaptability to automation, thereby reducing reliance on manual labor.
2. Product Side: Dual Improvement in Power Generation Efficiency and Long-Term Reliability
The synergistic effect of anti-reflective and high-reflectivity coatings results in a 2–4% increase in module power output;
The self-cleaning coating reduces operational and maintenance costs, while mitigating long-term power generation degradation.
A high-barrier coating protects the HJT/perovskite structure, extending its service life by 5–10 years;
Weather-resistant coating combined with sealant ensures stable outdoor operation of the modules for 30 years.
3. Industrial Sector: Integrating cutting-edge technologies to support industrial upgrading
It is perfectly suited for cutting-edge application areas—including HJT, TOPCon, BC, perovskite, flexible photovoltaics, offshore photovoltaics, and BIPV—serving as a core material foundation for the transition toward higher efficiency, thinner and lighter designs, and lower carbon emissions.
IV. Conclusion
The UV coating serves as the “optical protective layer” for photovoltaic modules, providing anti-reflective properties, self-cleaning capabilities, weather resistance, high barrier performance, and high reflectivity—thereby enhancing power generation efficiency and outdoor durability.
UV adhesive enables interconnection via solder tape, provides sealing and insulation, and ensures structural fixation, thereby replacing high-temperature processes and enhancing both yield and production capacity. Together, these two technologies are driving the photovoltaic industry’s comprehensive transformation—from a model characterized by “high temperature, high energy consumption, and low efficiency” to one defined by “low temperature, environmental friendliness, high efficiency, and extended service life” —making this material a pivotal force in supporting global carbon neutrality goals.
The UV curing adhesive range named above is one part of the JOME production line. For the earlier discussion of Complete Adhesive Application Solution for In Vehicle, follow the link, or browse the the JOME industrial adhesive range; specifications and samples go through the talk to the JOME application engineers.