The strength of a coating‘s adhesion to the substrate can easily be measured with the cross hatch test. The procedure requires that a “cross” pattern of 100 squares is carved on the surface by making 11 parallel cuts, approx. 5 cm long and at a distance of 1 – 2 mm from each other, and then repeating the 11 cuts perpendicular to the previous ones. The cuts must go through the coating down to the substrate. After that, a normalised tape, wide enough to cover the pattern, is pressed on it with a force of 10 N/cm2 and then sharply torn off. This operation has to be repeated 5 times in succession, every time using a new tape: no square should be pealed off. For intensification the test item can be boiled in water for 15 minutes and subsequently the tear off test can be repeated.
Please contact us for further information about the test methods.