Polyurethane
Ink Binder, as a core component of high-performance ink, its effect is mainly reflected in printing adaptability, film-forming performance and the final quality of printed matter. Through its unique chemical structure, it endows ink with a series of outstanding properties.
Firstly, it stands out in terms of printing adaptability and adhesion. Polyurethane binders exhibit excellent adhesion to a variety of substrates, such as treated polyethylene, polypropylene films, polyester films, aluminum foil, paper, etc. This is attributed to the polar groups in its molecular chain, which can form a strong interaction force with the material surface and even form weak chemical bonds, thereby effectively avoiding problems such as ink loss and color fading after printing. Meanwhile, it endows the ink with excellent leveling properties and appropriate viscosity, making the printing process smoother and the dot reproduction clear and complete.
Secondly, its film-forming performance determines the physical and chemical durability of the printed matter. The ink film formed after the curing of polyurethane has both high hardness and good flexibility. This seemingly contradictory feature makes the printed matter both scratch-resistant and wear-resistant, and can also adapt to subsequent processing procedures such as die-cutting and embossing without causing ink burst or cracks. More importantly, polyurethane binders can offer excellent resistance, including heat resistance, oil resistance and resistance to chemical solvents. This is crucial for the packaging of food, daily chemical products and other items that need to be stored for a long time or used in specific environments, ensuring that the patterns and text remain stable and bright under complex conditions.
Furthermore, in terms of presentation effect, polyurethane binders can effectively enhance the visual and tactile quality of the ink. It has good wettability and dispersibility for pigments, which can make pigment particles uniformly and stably suspended in the system, thereby fully exerting the color saturation and covering power of the pigments themselves, making the printed matter have bright, rich and high gloss colors. In addition, by adjusting the formula, different gloss effects from high gloss to matte finish can be achieved, meeting diverse design requirements.
Finally, environmental protection and safety are also its important advantages. At present, the mainstream waterborne polyurethane and solvent-free polyurethane binders have significantly reduced the emission of volatile organic compounds, which is in line with the development trend of modern green printing. Especially in the fields of food and pharmaceutical packaging, they offer higher safety.
In conclusion, polyurethane ink binder has comprehensively enhanced the overall performance of ink through its strong adhesion, excellent durability, superior film-forming performance and good environmental protection characteristics. This is ultimately reflected in the high quality, long service life and wide applicability of printed products. It is an indispensable key material in modern high-performance printing, especially in the field of composite flexible packaging.