Adams Wet Rub Tester No.2308

This tester measures resistance of coated paper against rub-off, which is one of important factors for offset printing management to prevent picking, etc. caused by damping water. On the rubber roll immersed in the vat the stainless steel drum with specimen on it is mounted and rotated; the drum stops after a certain number or rotations; then, the drum and rubber roll are washed with water, and the water in the vat is put in another container, and evaporated in vacuum at 120⁰C for four hours; the residue in the vat is weighed. The weighed value is divided by the specimen area to determine the amount of coating material detached per unit area.