Roughness is an important property of paper and board, as it has a significant influence on the steps in further processing, e.g. when printing or separating sheets.

The determination of roughness according to the Parker-Print-Surf method is carried out using the air flow method according to DIN ISO 8791-4 by means of a Parker-Print-Surf tester. The tester measures values within a measuring range of 0.6 µm - 6.0 µm.

The roughness according to Print Surf corresponds to the average distance between a sheet of paper or cardboard or carton and a flat ring surface pressed against it under defined conditions.

10 samples per test side are cut into at least 100 mm x 100 mm. An average value for the top and bottom side is formed from the individual values.