The gloss of an ink layer refers to the ability of a printing ink layer to reflect light from a certain angle under a fixed light source. The gloss of the ink layer has a great influence on the appearance of the printed matter, and the gloss is good and the color is bright, which can significantly improve the printing T grade. The gloss of the ink layer is mainly affected by the leveling property of the ink and the smoothness of the surface of the film material. The better the leveling property of the ink transferred to the film, the smoother the film surface, the better the gloss of the ink layer. In addition, the gloss of the ink layer is also affected by the following factors with the film material unchanged.
1. Solubility and Viscosity of Ink The stronger the solvent's ability to dissolve the ink, the better the ink dissolves and the gloss of the ink layer is better. The working ink viscosity is suitable. It is beneficial to the leveling of the ink and the gloss of the ink film is better. Ink degradation. Solvent imbalance, over-dilution and solvent impact not only affect the printing performance, but also destroy the ink structure, resulting in the separation of the pigment and the resin oil, and often significantly reduce the gloss of the ink layer.
2. The binder material not only plays a role in dispersing pigments, but also plays a role of protecting the pigments and showing luster. Adding a proper amount of varnish within the range allowed by the color density can increase the gloss of the ink layer to some extent.
3. Drying speed of ink In general, lowering the drying speed of the ink properly helps improve the gloss of the ink layer. The ink drying is too fast, and the ink after overprinting is easy to whiten. It appears that the matte ink dries too slowly, and adhesion and other troubles may occur, causing the ink layer to lose luster.
4. The squeegee squeegee blade angle is too large or the squeegee blade is too sharp (for example, a new blade), and the printed ink layer lacks luster. On the contrary, it is beneficial to increase the gloss of the ink layer.
5. In the printing process, the solvent volatilizes quickly and the ink film dries quickly. Due to the effect of evaporative heat dissipation, the heat around the ink film is absorbed, causing the water vapor in the air to condense abruptly, forming a fog on the surface of the printing ink film. The layer loses its luster and this effect is more pronounced in high humidity environments.