Potential Problems in Printing – Description of Problems and Proposed Solutions

Problem Solution
1. Too thin. 1. Reduce amount of thinner.
2. Transparent ink. 2. Use opaque color shade.
3. Wrong ink system. 3. Use pad printing ink .
4. Scanty ink transfer. 4. Locate defect in cliché or pad.
Problem Solution
1. Insufficient etching depth. 1. Produce new cliche with greater etching depth.
2. Areas not screened. 2. Screen area.
3. Areas not slanted. 3. Slant areas.
4. Wrong cliche type. 4. Use cliche which allows screen to be etched with it.
5. Wrong screen ruling. 5. Test new cliche with different fineness of half-tone screen.
Problem Solution
1. Too flat. 1. Use more tapered pad shape.
2. Porous surface. 2. Replace pad.
3. Too soft. 3. Use harder pad.
Problem Solution
1. Soiled surface. 1. Clean surface with alcohol.
2. Dark substrate color. 2. Double print.
3. Surface too rough. 3. Use harder, more tapered pad.
4. Stress cracks (esp. on injection molded parts). 4. Use milder ink/thinner system or quick drying ink/thinner to avoid any dissolution of substrate.
Problem Solution
1. Soiling from greasy residues on accessories(auxiliaries). 1. Clean cliche,doctor blade, etc.before installing.
2. Doctor blade sags. 2. Use harder or thicker doctor blade (or see cliche points 2 and 3).

This problem very often occurs in pad printing, and cannot always be solved satisfactorily. Due to the low degree of ink transfer in pad printing, 100 % opacity cannot be achieved on many objects with only a single printing, especially in the case of dark substrates. Increased hiding power can be attained by double or triple printing or preprinting with white.