ASTM D1639-90(1996)e1 PDF

1.1 This test method covers the measurement of the free acidity present in the nonvolatile portion of varnishes, oils, certain resins, and paint vehicles, by the reaction with standard alkali solution.

1.2 If carboxylic anhydrides are present, only one half of the reactive groups will be titrated and indicated by this test method.

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.