With the rapid growth of the flexible hybrid electronics (FHE) market (expected to reach US$400 million in 2031, with a CAGR of 14.5%), higher requirements are placed on adhesive materials: they must have flexible adaptability, low-temperature curing, high-precision bonding and environmental protection. Ultraviolet curing pressure sensitive adhesive (UV PSA) has become the core material for flexible electronic assembly due to its fast curing, low thermal stress and customizable characteristics. It is widely used in the manufacturing of wearable devices, flexible displays and smart sensors.
1. Core characteristics and technical advantages of UV PSA resin
Efficient curing mechanism
Under ultraviolet light, UV PSA triggers polymerization reaction through photoinitiator to achieve second-level curing (traditional process takes minutes to hours), avoiding high temperature damage to flexible substrates (such as PI film, PET circuit).
Environmental friendliness
The solvent-free formula significantly reduces VOC emissions, complies with environmental regulations such as EU REACH, and the curing energy consumption is reduced by more than 60% compared with the hot melt process.
Mechanical adaptability
By adjusting the monomer/oligomer ratio, the modulus (0.1–10 MPa) and elongation at break (50–300%) can be customized to match the dynamic bending requirements of electronic components.
2. Analysis of multi-field application scenarios
1. Coatings: Precision protection and optical performance
High-transmittance coating: UV PSA resin is used for flexible OLED screen protective coating, with transmittance > 92% (400–700 nm) and color difference ΔE < 1.5 (after 1000 hours of QUV aging).
Case: Shanjin Optoelectronics uses UV curing process to achieve zero VOC emission of PSA, which is applied to LCD/OLED display module packaging.
2. Ink field: key materials for printed electronics
Conductive ink bonding: Jet-printed UV PSA can be accurately coated on curved substrates, solving the problem of hard surface delamination, and improving peel strength by more than 40%.
Technology trend: Low viscosity formula (such as 8000cPa.s) is suitable for inkjet printing and supports 25m/min production line speed.
3. Adhesives: Structural bonding reliability
Weather resistance breakthrough: 100% solid UV PSA (such as GC152-1) maintains shear strength (3.2 kgf/cm²) for 48–72 hours at 110°C, suitable for automotive electronics.
Biocompatibility: ISO 10993-certified formulas are used for medical sensor patches and support long-term skin contact.
4. Pressure-sensitive adhesives: Flexible assembly innovation
Low-stress bonding: UV PSA can form reliable bonding at a pressure of 0.1N/cm², reducing the risk of displacement of precision components.
Reworkability: Special formula supports non-destructive peeling and improves the efficiency of flexible circuit rework.
3. Shenzhen U-Sunny T-7333 resin: the optimal choice for flexible electronic bonding
The T-7333 bifunctional polyurethane acrylate resin launched by Shenzhen U-Sunny is specially designed to solve the shrinkage and deformation of film substrates:
Low shrinkage characteristics: volume shrinkage rate <3%, avoid PET/PVC substrate warping, and adapt to optical grade tape.
Mechanical properties:
Elongation at break 85%, withstand 100,000 bending times (radius of curvature R=3mm)
Tg=-45℃, guarantee flexibility under -40℃~80℃ working conditions
Process compatibility:
Viscosity 8000cPa.s (25℃), support roller coating/spraying
3 seconds surface drying (120mJ/cm² UV LED), improve production line efficiency
Application scenarios:
Metalized film label (180° peel strength 8N/cm)
Solar back panel tape (hydrolysis resistance 500 hours)
Medical dressing (transmittance water white level)
UV PSA resin is reshaping the flexible electronics manufacturing process through its fast curing, flexible adaptation, and environmental compliance. Shenzhen U-Sunny's T-7333 and other innovative products are driving industry upgrades with low shrinkage and broad-spectrum bonding capabilities. In the future, with the development of bio-based monomers and the maturity of low-temperature UV-LED curing technology, UV PSA will unleash greater potential in emerging fields such as smart packaging and implantable medical devices.