Screen dots are desirable for some prints, but not for others. Some photopolymer cliches cannot be produced without a screen, or only with a certain type of screen. With steel cliches, the screen is only exposed in for support of the doctor blade, to allow printing of larger motifs over an entire surface.
Problem | Solution |
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1. Too thick. | 1. Thick ink with fast thinner produces visible screen dots. |
2. Too thin. | 2. Thin ink with slow thinner (retarder) causes invisible screen dots. |
Problem | Solution |
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1. Etching too deep. | 1. Produce new cliche with shallower etching depth. |
2. Wrong screen ruling. | 2. Depending on results desired, use finer screen for invisible screen dots or coarser screen for visible screen dots |
3. Wrong cliche type. | 3. Use cliche type suited to screen type. |
Problem | Solution |
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1. Wrong pad shape. | 1. Depending on results desired, use more tapered pad for visible screen dots or flatter pad for invisible screen dots. |
2. Surface too rough. | 2. Replace pad. |
Problem | Solution |
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1. Surface too coarse/ very structured. | 1. In this case, not the screen dots are visible, but the surface structure. |
Problem | Solution |
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1. Poor quality of artwork. | 1. Check screen dot pattern on film or expose in new screen. |
Blurred print is understood as the indistinct, hazy reproduction of lines or letters. This deficiency is often confused with distortion.