Small air bubbles (pinholes) visible
Ink
Problem
1. Too thick.
Solution
1. Add thinner.
Cliche
Problem
1. Poor etching.
Solution
1. Examine cliche with magnifying glass; produce new cliche as needed.
Pad
Problem
1. Surface damaged.
2. Wrong shape.
3. Too soft.
Solution
1. Replace pad.
2. Use more tapered pad shape.
3. Use harder pad.
Substrate
Problem
1. Statically charged.
2. Contaminated with dust particles.
Solution
1. Install ionizing unit.
2. Pre-clean. objects, if necessary, using air hose (air jet).
Other
Problem
1. Soiled artwork.
2. Dust present when films are copied.
3. Unclean environment, dust circulating in surrounding air.
Solution
1. Checks films.
2. Produce new cliche.
3. Dust particles, which appear to be air bubbles, can be transferred by pad from substrate to ink.
This deficiency can be contained easily. If bubbles always appear in same place, Problem
will be found in
cliche or pad. If position of bubbles shifts, Problem
is caused by dust particles or electrostatic charges.
