ASTM D2697-03 (R2021) pdf free download.Standard Test Method for Volume Nonvolatile Matter in Clear or Pigmented Coatings.
1 .1 This test method is believed to be applicable to the determination of the volume of nonvolatile matter of a variety of coatings. An interlahoratory study to establish the precision of this test method included a water-reducible exterior latex paint and three automotive coatings that included a solvent- reducible primer surfacer, water reducible primer surfacer, water reducible enamel topcoat, and acrylic dispersion lacquer topcoat. Earlier collaborative studies included a gloss enamel, a flat wall paint, a gloss house enamel, an industrial baking enamel, an interior latex paint, and an exterior latex paint.
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
3. Summary of Test Method
3.1 The weight and volume of a stainless steel disk is to be determined; after the disk is coated with the material being tested. The weight and volume of the disk plus dried coating is determined by weighing in air and then by weighing in a liquid of known density. The volume being equal to the quotient of the weight loss of the coated disk (due to the Archimedes buoyancy effect) divided by the density of the liquid displaced. The liquid may be water, organic liquid such as low-solvency mineral spirits or kerosine, or with special modifications not covered specifically in this method, mercury. The choice of liquid depends upon the nature of the coating tested.
Note 1—Distilled waler is suitable for most paints. Excepüons are coatings that contain ingredients that are readily leached out of the dry film by the water and low-gloss coatings, the surface of which is poorly wet by water even with surfactant added. (Note 2) Low-solvency hydrocarbon solvent (KB below 36) is also practical tr most paints and is preferred by some workers.4 Ii is considered to be particularly good for paint films not readily wet by water. Analogously, organic solvents must not be used if the coating to be tested contains ingredients that will be dissolved readily by the solvent. Lacquers containing monomeric plasticizers would be examples where hydrocarbon solvents should definitely not be used. Coatings formulated much above the CPVC present a special problem. where mercury might be the desired “suspending” liquid (Note 3), and for solvent-reducible paints hydrocarbon solvent might be considered the poorest (unless it is the objective to obtain values closer to “theoretical” spaces between pigment particles not filled with binder, becoming partially filled with solvent during the test).
Note 2—Concentration of surfactant must be kept very low or literature values for the density of the waer cannot be used.
Note 3—Details of the mercury displacement techniques can be found in the literature.
3.2 From the measured weights and volumes of the disk before and after coating, the weight and volume of the dried coating film are calculated. ASTM D2697 pdf download.