Why the printer of vibratory stress relief equipment prints blank paper?

Why the printer of vibratory stress relief equipment prints blank paper?
Printer can roll paper normally, but still prints blank.
May be the printer ribbon ink is volatilized for long time use, leading to be unable to print color.
At this time, open the printer panel and take out the ribbon.
Drop the ink (2drops) on the ribbon and penetrate after rolling the ribbon.