T‑7050 is a difunctional polyurethane acrylate UV resin featuring broad substrate adhesion, exceptionally high elongation, excellent yellowing resistance, moderate curing speed, and outstanding flexibility. It is supplied as a 100% solids material, contains no monomers in its neat form, emits no irritating odor, and exhibits low shrinkage upon curing. Key physical properties include a glass transition temperature (Tg) of –18°C, a molecular weight of approximately 2,600, an elongation at break of 75%, a viscosity of 25,000 mPa·s at 25°C, and a Gardner color value ≤2.
Core Performance Advantages
Wide Substrate Adaptability
The most notable feature of T‑7050 is its excellent adhesion to a diverse range of substrates. On organic materials, it bonds well to TPU, PVC, ABS, PC, PA, PET, BOPP, melamine boards, and even untreated PP (polypropylene). On inorganic surfaces, it provides strong adhesion to glass and metals. Particularly in PP electroplating primer applications, T‑7050 can serve as the main resin, offering a reliable foundation for subsequent metal deposition.
High Flexibility and Elongation
Cured films of T‑7050 exhibit outstanding flexibility, with an elongation at break of 75%, allowing them to withstand repeated bending, stretching, and deformation without cracking. This property makes it especially suitable for leather coatings, soft TPU articles, and other flexible substrates that must endure mechanical stress.
Yellowing Resistance and Appearance Stability
T‑7050 provides good resistance to yellowing, which helps maintain long‑term clarity and color stability of the coating. With a Gardner color value ≤2, it offers a distinct advantage in applications requiring high optical quality.
Leveling and Pigment Wetting
The resin shows excellent leveling properties, resulting in smooth and uniform coating surfaces. At the same time, it exhibits superior wetting and dispersing capability for pigments and fillers, making it highly effective in pigmented ink systems and in coating low‑surface‑energy substrates.
Curing Performance
T‑7050 offers a moderate curing speed. Under standard UV curing conditions, a minimum energy dose of 800 mJ/cm² is recommended to achieve full crosslinking. This curing condition is compatible with both mercury vapor lamps and LED light sources, providing flexibility in production line integration while maintaining consistent performance.
Typical Applications
UV Coatings
In the field of UV coatings, T‑7050 finds its core application as a primary resin for PP electroplating primers. In addition, it is suitable for primers or topcoats on challenging plastics such as PA, PET, BOPP, and melamine boards. For vacuum metallization processes, it is advisable to blend T‑7050 with pentaerythritol triacrylate (PET3A) to ensure proper drying of the primer layer. The cured coating does not exhibit iridescence or haze issues after electroplating.
UV Inks
When printing on non‑absorbent substrates like TPU, PVC, BOPP films, glass, or metals, T‑7050 can be used as a primary or auxiliary resin to reinforce the adhesion between the ink layer and the substrate, preventing delamination or peeling.
UV Adhesives
T‑7050 is well‑suited for structural bonding and surface coating of glass, metals, and certain plastics in UV adhesive applications. Its high flexibility and low shrinkage help absorb and relieve stress caused by differential thermal expansion of dissimilar materials, thereby improving long‑term joint reliability.
Formulation Compatibility Guide
Monomer Selection
T‑7050 is miscible with a wide variety of conventional monomers. When used as a binder, to reduce the negative impact of high‑functionality monomer shrinkage on adhesion, it is recommended to incorporate monomers such as FM‑350B or CTFA (methoxy or acrylate types). These monomers help lower volumetric shrinkage and further enhance adhesion while maintaining fast cure response.
Solvent Selection
T‑7050 dissolves readily in esters, ketones, and aromatic hydrocarbons. It is not soluble in straight alcohols alone but can be dissolved in mixed solvent systems containing alcohols and ethers.
Polymer Compatibilization
This resin exhibits good compatibility with polyesters, epoxies, polyurethanes, phosphates, and acrylic polymers, giving formulators flexibility in system design. Combining T‑7050 with Trust 7210 (a difunctional polyurethane acrylate) has been shown to further improve the adhesion between TPU electroplating primers and the subsequently deposited metal layer.
Curing and Processing Recommendations
For optimal performance, a UV energy dose of no less than 800 mJ/cm² is recommended. The resin works equally well under mercury or LED lamps. In electroplating applications, the cured primer layer does not show rainbow patterns or haze, ensuring a clear, defect‑free metallic finish.
Storage and Packaging
T‑7050 is available in 20 kg plastic pails or 200 kg iron drums. It should be stored in a cool, dry place away from direct sunlight and high temperatures, in tightly sealed containers to prevent contamination and moisture uptake.
Conclusion
T‑7050 is a UV‑curable difunctional polyurethane acrylate that combines broad substrate adhesion, high elongation, and excellent yellowing resistance. Its monomer‑free formulation, low shrinkage, and non‑irritating odor make it a versatile choice for UV coating, ink, and adhesive systems that demand both flexibility and environmental compatibility.
In practice, T‑7050 effectively resolves adhesion challenges on difficult organic plastics such as PP, PA, PET, BOPP, and melamine boards, as well as on inorganic surfaces including glass and metals. It is particularly well‑suited for PP electroplating primers, vacuum metallization basecoats, and high‑flexibility leather/TPU finishes. Its moderate curing speed and compatibility with both mercury and LED UV sources allow easy integration into existing production lines.
From a formulation perspective, T‑7050 exhibits good miscibility with common monomers, solvents, and various polymer resins. Its excellent wetting and dispersing properties for pigments and fillers provide formulation flexibility for a wide range of applications. For optimal crosslinking and stable adhesion, a minimum UV energy of 800 mJ/cm² is recommended.
Overall, T‑7050 serves as a reliable backbone resin for UV systems requiring high flexibility, strong adhesion, and low shrinkage, making it a practical solution for diverse substrates and demanding process conditions.