In the packaging and printing industry, four-color banners are sometimes used.Printing Process For Making Four-Color Banners
1. Exposure and printing table device: an exposure table is made of angle iron, the table top is made of 1cm glass, and the lower layer is equipped with light tubes, which is not only an exposure table, but also can be printed on it.Printing Process For Making Four-Color Banners
2. Three point positioning device for plate printing and printing: make two positioning brackets with angle iron. Each screen exposure, printing close to the three fulcrum, in order to ensure the four screen rules in the printing process.Printing Process For Making Four-Color Banners.
3. Production of simple printing bag: cover the whole screen frame with a transparent plastic cloth (put a thick sponge on the screen), stick the four sides of the plastic cloth on the exposure table with adhesive tape, make a round opening on the side of the plastic cloth, Printing Process For Making Four-Color Banners
Insert the tube head of high-power vacuum cleaner into the round opening, seal the four sides with adhesive tape, and compress the sponge with the plastic cloth through vacuum, So it becomes a simple vacuum plate printer.Printing Process For Making Four-Color Banners
4. Exposure time: the exposure time is determined according to the light source intensity and the distance between the light source and the screen. The light intensity and distance are short, and the exposure time is short, otherwise it is long. In general, it’s better to have a longer exposure time than underexposure.Printing Process For Making Four-Color Banners
If the time is too short, one is that the development will lose the dot, the other is that there will be obscuration, resulting in blocking the version. The field pattern is obscured, which can be pierced by high-pressure water gun after secondary exposure, and the dot plate is easy to damage the dot by this method.Printing Process For Making Four-Color Banners