In gravure and flexographic printing industry, for kinds of reasons, there are lots of impurities mixed into ink such as fiber, wastepaper, iron filings, oxide and other debris.

• 在柔版及凹版印刷过程中，由于种种原因油墨中会含有如纤维、纸屑钢刮刀磨损铁屑等其它杂质。