[careprint]

#3013

Poor (spotty) release of ink by pad

Ink

Problem
1. Dried out on pad.
2. Too wet on pad, not tacky.

Solution
1. Use slower thinner.
2. Use faster thinner.

Cliche

Problem
1. Insufficient etching depth.
2. Etched too deeply.
3. Wrong screen ruling.

Solution
1. Produce new cliche with greater etching depth.
2. Produce new cliche with shallower etching depth.
3. Use new cliche with different fineness of halftone screen.

Pad

Problem
1. Wrong shape pad.
2. Surface roughened.

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

Substrate

Problem
1. Soiled surface (grease, oil, perspiration, mold release agents..).
2. Surface insufficiently per-treated (polypropylene).

Solution
1. Pre-clean objects.
2. Check per-treatment, repeat as required.

Other

Problem
1. Print speed setting too slow.
2. High ambient (room) temperature.

Solution
1. Maintain uniform cycle time.
2. Optimal room temperature is 18 °C – 20 °C or 65 °F – 68 °F.

Incomplete or spotty deposit of ink by pad is referred to as “splitting.” It plays a minor role in a continuously running process. The Problem only arises when cycle times fluctuate or after short breaks. The pad deposits the dried ink all at one time, producing an inconsistent image. Using fast thinners will decrease ink build-up and improve ink deposition.

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