ASTM D4946-89(2003)

Dry paint often comes in contact with itself especially in window and door areas and, depending on its hardness, the pressure, temperature, humidity, and duration of time the surfaces are in contact, sometimes sticks to itself (blocks). This stringent test method can be used to compare and rate subjectively the resistance of paints to blocking.

1.1 This test method describes an accelerated procedure for evaluating the face-to-face blocking resistance of trades sales paints. This is not to be confused with blocking resistance Test Method D 3003, which is concerned with blocking of industrial coatings on metal substrates, nor with Test Method D 2793 which is concerned specifically with wood product finishes and reports results on a satisfactory or not satisfactory basis, rather than by the degree of blocking tendency as in this test method.

1.2 The values stated in the SI units of measurement are to be regarded as the standard. The values given in parentheses are for information only.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.