1. Requirements for white ink for tinplate caps: (metal tinplate bottle cap)
The surface appearance of tinplate is silvery white or yellow, with metallic luster. Before printing colored text and patterns, the surface needs to be painted white or printed. Affected by the binding force of ink, it will not turn yellow after repeated high-temperature baking, and will not fade after high-temperature cooking. . The tinplate primer can increase the adhesion to the tinplate, and the white ink has excellent adhesion. Commonly used primers are epoxy amine-based, with light color, no yellowing after repeated baking, no aging characteristics, good flexibility, and impact resistance.
2. Requirements for tinplate covers for colorful inks:
In addition to certain water resistance, printing color ink also has its special requirements. The surface of tinplate is impervious to water and solvents, and needs to be dried by baking, so the ink needs to be thermosetting. It has higher requirements on the coloring strength and durability of pigments. In addition to the base material function of general offset printing ink, iron printing ink should also have heat resistance, strong ink film adhesion, impact resistance, hardness, cooking resistance and light resistance according to the characteristics of iron printing ink.
3. Adhesion and function of tinplate cover ink
If it is made into food cans, it can also be said to be packaging cans, because tinplate printing is finally made into food cans, toys, metal frames and chemical product barrels, which require various processes such as cutting, bending and stretching, so printing inks need to have good quality. Adhesion and corresponding mechanical function. In order to improve the adhesion of the ink, the first requirement before printing is to tinplate the tinplate with a white background. The entire screen is dominated by white, with high brightness. After adding other high-energy tones, it can increase the brightness of the color and form a color layer.