In glass
screen printing products, a problem often arises with jagged burrs (including defects or broken lines) at the edges of the printed ink film. There are many reasons for burrs, but the main reason is the quality of the screen printing version.
1 The sensitivity of the photosensitive adhesive is not high, which causes the fine line mountain to be broken or broken.
2 The exposure time is insufficient or the exposure time is too long, the development is not sufficient, and the edge of the screen printed graphic is not neat and jagged. For a good screen printing plate, the edges of the graphic should be smooth and tidy.
3 When the surface of the screen printing plate is unevenly coated, there is still a gap between the screen printing plate and the substrate during printing, and the edge of the printing ink is burred due to the ink vacancy.
4 During the printing process, due to the expansion of the plate film after contact with the solvent, and the degree of warp and weft expansion is different, the surface of the plate film is uneven, and a gap occurs between the screen printing plate and the substrate at the time of printing, and the ink hangs in the air. The ink film will have burrs. In order to prevent the occurrence of jagged haircuts, the solution can be considered from the following aspects:
1 select high mesh screen plate;
2 Select a photosensitive material with high resolution; make a bridge type and good resolution.
3 making a screen printing plate with a certain photosensitive film thickness to reduce the expansion deformation;
4 It is also possible to use a skewed stretch net method to stretch the net, and the good angle is 22.5.
5 fine line printing, can also be used in indirect plate making, because the indirect legal version of the burr may be smaller:
6 In the process of plate making and printing, try to control the temperature expansion factor, using a photosensitive material with a small expansion coefficient:
7 Improve the quality of the plate making, ensure that the surface of the screen printing plate is smooth and smooth, and the edges of the screen lines should be neat;
8 spray the screen printing plate with a water spray gun to improve the development effect;
9 The distance between the screen and the substrate, the angle of the squeegee, and the printing pressure should be appropriate.
