What is the Reason UV Print Heads Present Ink Break and Drawing?

After using UV printer with Ricoh print heads, there will be a common problem, the printed products present a phenomenon of drawing, that is faults which look like wavy silk pattern. So why does this happen?

To figure out the reason we must first explain how the print head works. The print head for large format UV printer is consist of thousands of sophisticated nozzles and is able to print 1 color or several colors at the same time. Take reference with Ricoh print head, each Ricoh GEN5 print head contains 1280 nozzles, which is a type of grey-scale piezoelectric print head with multi-drop printing technology, min 7PL, max 21PL, photo-precision, able to print 2PT alphabets clearly, it is with high accuracy. So when the print head is operating and one of the nozzles is not working or lost the ability to jet ink, the drawing happens.

Reason A: One of the nozzles blocked, lead to drawing.
Solution: Jet the UV cleaner to clean the print head, or dip the print head several hours with alcohol than use the cleaner.

Reason B: The air in the nozzle blocked the ink.
Solution: Use the ink purge function to press the ink and squeeze out the air.

Reason C: Aging print head
Solution: Replace the print head