[careprint]

#3017

Insufficient opacity

Ink

Problem
1. Too thin.
2. Transparent ink.
3. Wrong ink system.
4. Scanty ink transfer.

Solution
1. Reduce amount of thinner.
2. Use opaque color shade.
3. Use pad printing ink .
4. Locate defect in cliche or pad.

Cliche

Problem
1. Insufficient etching depth.
2. Areas not screened.
3. Areas not slanted.
4. Wrong cliche type.
5. Wrong screen ruling.

Solution
1. Use new cliche with greater etching depth.
2. Screen area.
3. Slant areas.
4. Use cliche which allows screen to be etched with it.
5. Test new cliche with different fineness of halftone screen.

Pad

Problem
1. Too flat.
2. Porous surface.
3. Too soft.

Solution
1. Use more tapered pad shape.
2. Replace pad.
3. Use harder pad.

Substrate

Problem
1. Soiled surface.
2. Dark substrate color.
3. Surface too rough.
4. Stress cracks (esp. on injection molded parts).

Solution
1. Clean surface with alcohol.
2. Double print.
3. Use harder, more tapered pad.
4. Use milder ink/thinner system or quick drying ink/thinner to avoid any disSolution
of substrate.

Other

Problem
1. Soiling from greasy residues on accessories (auxiliaries).
2. Doctor blade sags.

Solution
1. Clean cliche, doctor blade, etc. before installing.
2. Use harder or thicker doctor blade (or see cliche points 2 and 3).

SPECIAL NOTES
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 pre-printing with white.

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