Polyurethane resin is a type of polymer that can function as a binder in film printing inks. Here's how it contributes to the performance of the ink in a film printing application:
1. Adhesion: Polyurethane resin are known for their excellent adhesion properties, which allows the ink to strongly adhere to various film substrates such as polyethylene (PE), polypropylene (PP), and other plastic films. This ensures that the printed design remains intact and durable, even under stress or exposure to different environmental conditions.
2. Flexibility: Polyurethane binder offer high flexibility, which is crucial for printing on flexible films. The ink must be able to withstand bending and stretching without cracking or peeling, and polyurethane resins provide this necessary elasticity.
3. Abrasion Resistance: In packaging and other applications where the printed film may be handled frequently, the ink needs to withstand abrasion. Polyurethane resins can enhance the abrasion resistance of the ink, preserving the quality of the printed image or text.
4. Chemical Resistance: Polyurethane resins often exhibit good resistance to chemicals, including solvents and other substances that the packaged goods may come into contact with. This feature is important for maintaining the integrity of the printed image and ensuring that the ink does not degrade due to chemical exposure.
5. UV Resistance: Polyurethane resins can also provide ultraviolet (UV) light resistance, which is essential for products that will be exposed to sunlight or UV radiation. This helps prevent color fading and ensures the long-term vibrancy of the printed design.
6. Weatherability: Similar to UV resistance, polyurethane resins can improve the weatherability of the ink, making it suitable for outdoor use or for applications where the printed film may be exposed to varying weather conditions.
7. Printability: Polyurethane resins can contribute to the overall printability of the ink by ensuring good wetting and leveling on the film surface, resulting in a uniform and clear print.
8. Compatibility: They are often designed to be compatible with other components of the ink formulation, such as solvents, pigments, and additives, allowing for the creation of a stable ink system with the desired properties.
In summary, polyurethane resins used as binders ins film printing ink provide strong adhesion, flexibility, abrasion resistance, chemical resistance, UV resistance, weatherability, printability, and compatibility, all of which are crucial for producing high-quality printed films that meet the specific demands of the application.