Twelve, ink

Ink is the phenomenon of ink overflowing outside the printed lines. As shown in Figure 4-36, when printing a line, ink spills on the side of the direction of the squeegee and affects the neat lines. This phenomenon is called bleed. The ink can be solved by adjusting the relationship between the printing plate and the ink, the operation of the squeegee, and the relationship of the screen stretching angle. The shape of the through hole portion of the screen printing plate varies depending on the plate making method (indirect method, direct method, straight line method). The ideal through hole should be able to seal with the surface of the substrate during the squeegeeing. With the ideal through hole shape of the printing plate, the printed ink film is sharp, neat, and accurate in size, without ink. In order to prevent the occurrence of smoke and ink phenomenon, the film should have appropriate thickness, elasticity, and smoothness. For this purpose, a soft nylon mesh and a high-precision polyester mesh plate can be used. In order to prevent blemishes, it is best to use diagonal stretching in the plate making process.