How to improve ink adhesion of blank labels through surface treatment?
Publish Time: 2024-12-11
The ink adhesion effect of blank labels directly affects the quality and durability of the labels after printing. Appropriate surface treatment can significantly improve this situation.
First of all, corona treatment is a common and effective surface treatment method. The principle is to use high-voltage discharge to ionize the air, generate ozone and plasma, and oxidize and polarize the surface of the label material. This process increases the roughness of the material's surface and increases its surface energy, thereby enhancing the affinity of the ink molecules to the label surface. For example, for blank labels made of non-polar polymer materials such as polyethylene (PE) or polypropylene (PP), the wettability of the surface is significantly improved after corona treatment, and the ink can spread and adhere better, reducing the Ink peeling and blurring.
Plasma treatment is also an advanced technology to improve ink adhesion. By placing the label in a plasma environment, the active particles in the plasma react chemically with the surface of the label, introducing polar functional groups, such as hydroxyl groups, carboxyl groups, etc. These functional groups greatly change the chemical properties of the surface, changing it from low surface energy to high surface energy, just like building an "adsorption bridge" for the ink molecules. Whether it is paper or plastic blank labels, plasma treatment can effectively improve the adhesion firmness of the ink without changing the properties of the material itself. The treatment has good uniformity and can accurately control the depth and range of the treatment.
Coating treatments also play an important role in improving ink adhesion. A special coating, such as an acrylic or polyurethane coating, is applied to the surface of the label. These coatings have good adhesion and ink affinity. On the one hand, they fill up the tiny defects on the material surface and provide a smoother and more uniform printing basis. On the other hand, the chemical components in the coating can interact with the ink. Components such as resins and solvents interact to form chemical bonds or physical adsorption, enhancing the adhesion of the ink on the label. Moreover, different coating formulas can be adjusted according to specific ink types and printing process requirements to achieve optimal adhesion.
Additionally, the application of primers is also a viable strategy. Primer is an interlayer material specifically designed to enhance adhesion between ink and substrate. It can penetrate into the surface pores of the label material and form a good bonding interface with the ink. For example, for some label materials with smooth surfaces and difficult to adhere to ink, applying a layer of primer first can significantly improve the adhesion stability of the ink. Even when the label is affected by external factors such as friction, moisture, or temperature changes, the ink will It is also not easy to fall off, ensuring the clarity and durability of label printing information.
