1.1 This specification establishes requirements for composition, physical properties, performance, and labeling of gouache paints.

1.2 This specification covers pigments, vehicles, and additives. Requirements are included for pigment identification, lightfastness, and consistency.

1.3 Table 1 lists some pigments meeting the lightfastness requirements in this specification. In order to identify other pigments that meet these requirements, instructions are given for test specimen preparation. Test methods for determining relative lightfastness are referenced.

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

X2.1.1 This test method is used to test opacity of paints. Several drawdown bars having different aperture sizes are used.