How to solve the cycle watermarks around the plating hole?

How to solve the cycle watermarks around the plating hole?

Phenomenon:

Single side or double side, every hole, hole’s periphery, watermark, like any water remain after naturally dried.

Possible reason and solution:

Some people called this phenomenon fisheye, this phenomenon is in relation to the Chlorine content. If there is an absolute watermark, it may apply for imperfect water clean before baking, the remained water in the holes was very easy to flow on the copper surface, so the watermark arose in the baking process.

 

Phenomenon:

Single side or double side, every hole, hole’s periphery, watermark, likes any water remains after naturally dried.

Possible reason and solution:

Some people called this phenomenon fisheye, this phenomenon is in relation to the Chlorine content. If there is an absolute watermark, it may apply for imperfect water clean before baking, the remained water in the holes was very easy to flow on the copper surface, so the watermark arose in the baking process.

This phenomenon is particularly likely to occur with small holes or deep holes. The watermarks should be teardrops rather than concentric circles, and the edge hole will also have some traces of floating water droplets caused by drying. This phenomenon will be improved by washing.