The appearance of spots in glass screen printing

Zimo Zimo refers to the appearance of speckled marks on the graphic and dark parts of the glass surface, which damages the printing effect. Glass screen printing is prone to this phenomenon. The reasons are as follows: printing speed and slow drying of ink; The ink layer is too thin; Ink has high thixotropy; The influence of static electricity; Poor dispersion of pigments in ink results in the aggregation of pigment particles due to their polarity, resulting in color spots and imprints. The improvement method is to improve the fluidity of the ink; Use quick drying flux; Try to print with high viscosity ink as much as possible: increase the wet film thickness of the ink, and use ink made of pigments with low oil absorption as much as possible: minimize the impact of static electricity. 10. During image deformation printing, the pressure applied by the scraper to the printing plate can make linear contact between the printing plate and the printed object, and should not exceed. If the printing pressure is too large, the contact between the printing plate and the substrate will cause the silk screen to expand and deform, causing the printing image to deform. Screen printing is the type of printing with the smallest printing pressure among various printing methods, and if we forget this, we cannot produce good printed matter. If printing cannot be done without increasing the pressure, the gap between the layout and the glass surface should be reduced, so that the pressure on the scraper can be reduced.