Fineness
The fineness reflects the degree of dispersion of pigments and fillers in the vehicle, or in other words, the size of the pigment particles that are sheared and pulverized in the vehicle. This is a very important quality indicator of the ink, which is related to the properties, rheology and economic value of the ink.
The fineness of the gravure ink is especially important, if the ink is very thick, the scraper and the printing plate will be destroyed, the ink is easy to precipitate, the ink performance is not good, the leveling and fluency are not good, thus reducing the printing suitability and the pigment former Can not fully play and so on.
Considering that the image and text on the gravure are deeply concave and the ink layer is thick, it must be 15 microns to 25 microns.
The methods and instruments are the same as those for offset printing and ink fineness inspection methods for stereotyped printing, but a few points need to be emphasized:
(1) After taking the ink, put it directly on the scraper for scraping and checking, no need to dilute.
(2) It should be noted that due to the thinner gravure ink and the particularity of the grinding equipment (sand mill, ball mill), it is easy to mix air bubbles, and the air bubbles in the mill need to be cleared before inspection.
(3) The inspection operation requires quickness and agility.
