Surfaces appear patchy
Ink
Problem
1. Too thin.
2. Wrong ink system.
3. Transparent ink.
Solution
1. Use new ink.
2. Use another pad printing ink.
3. Use opaque ink.
Cliche
Problem
1. Etching too shallow.
2. Wrong cliche type.
3. Wrong screen ruling.
4. Motif not slanted.
5. Different etching depth.
Solution
1. Produce new cliche with greater etching depth.
2. Use different cliche type.
3. Test new cliche with different fineness of halftone screen.
4. Slant motif.
5. Produce new cliche with constant etching depth.
Pad
Problem
1. Wrong shape.
2. Too soft.
3. Surface too rough.
Solution
1. Use more tapered pad shape.
2. Use harder pad.
3. Replace pad.
Substrate
Problem
1. Surface structure too irregular.
2. Soiled surface. olution
Solution
1. Use hard, pointed pad shape.
2. Pre-clean objects, e.g., with alcohol.
Other
Problem
1. Doctor blade sags.
2. Only printed once.
Solution
1. Use stronger doctor blade, or screen areas or slant lines.
2. Double print or preprint opaque ink.
This deficiency is easily observed in prints where peripheral areas are acceptable, but coverage (hiding) worsens
progressively toward center. See also “Insufficient Opacity.”
