【国外标准】 Standard Test Method for Leveling of Paints by Draw-Down Method

4.1 Leveling can affect the hiding and appearance of applied architectural coatings, the presence of brushmarks and surface irregularities being more conspicuous with gloss and semi-gloss finishes than with flat finishes. Instrumental evaluations of leveling by this test method have been shown to correlate with those made by brush application.1.1 This test method2 covers the laboratory determination of the relative leveling of water and solvent-reducible architectural paints in white and light tints by comparing the ridges produced in a draw-down film to a series of plastic leveling standards.1.2 Unpigmented, texture, and deep-tint coatings cannot be readily evaluated with the shadowing produced by oblique lighting employed in this test method. Such coatings may be rated by comparing them with the plastic standards at various angles of reflection. For this purpose ordinary room lighting is satisfactory.1.3 Since other factors may influence the tendency of liquid paints to sag, this test method is not intended to measure sagging.1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.5 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.