A defect of gravure printing, characterized by accumulating ink on the non-printing areas of the gravure cylinder (which then is transferred to the substrate). Fogging is caused by the attraction certain inks have for the chromium surface of the cylinder, or by poorly ground pigment particles adhering to the cylinder and failing to be wiped off by the doctor blade. Fogging may also be caused by surface irregularities in a new chrome cylinder, which cause ink to collect there. One way of remedying this problem is by using a fast-drying solvent ink, which will dry on the surface of the cylinder before contacting the substrate. Fogging is also called scumming.
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