Screen printing consists of five elements: screen printing, scraping, ink, printing and printing. The basic principle of screen printing is to print the basic principle of printing ink by using the screen printing plate of the screen and text. When printing, the ink is poured on one end of screen printing plate, and a certain pressure is applied to the ink part of screen printing plate by scraping and printing scraper. Meanwhile, it moves towards the other end of screen printing plate. The ink is moved by the scraper from the mesh hole of the graphic part to the seal in the movement. Due to the viscous effect of the ink blot. In a certain range, always in the process of printing scraper and screen printing plate and a line contact, the contact line with the scraper moves, due to maintain a certain gap between the screen and substrate, so that the screen printing plate through the tension and cause of the scraper the reaction, the reaction is called resilience. Due to the effect of resilience, the screen plate is only in contact with the movable line, while the other parts of the screen plate are disconnected from the bearing. It makes the ink and screen broken, ensures the precision of the printing size and avoids the rubbing of the dirty bearing material. When scraper wind up after the whole layout, and silk screen plate also raised, and the ink scraping back to the initial position. This is a print trip.