Meaning and use

5.1 Coating companies and raw material suppliers can use this standard to evaluate the interaction of primer and topcoat in providing good enamel retention. A primer/top coat system with very good enamel retention will produce the desired gloss in the first coat coat application.

Step 1: Scope

1.1 This standard provides a method for determining the retention characteristics of primer and top paint applications. The standard topcoat is used to determine the absorption characteristics of the primer. Enamel retention can be measured as the difference in finish gloss observed on the primer with respect to the gloss gloss of the same finish on a non-porous smooth surface.

The 1.2 standard is written in the context that the user will evaluate the enamel retention properties of the primer. Alternatively, the standard can be used as a method of evaluating the enamel retention properties of primer/topcoat systems where the primer is constant and different topcoats are used as test coatings.

1.3 This standard may also be used to evaluate coatings other than primers as first coatings. In this change, the user can test the enamel retention properties of the undercoat coat, or use any other type of paint as the primer, and then apply a standard top coat.

ASTM D7786-19 Standard Test Method for Determination of Enamel Fixation

1.4 Values expressed in SI units shall be regarded as standard values. No other units of measurement are included in this standard.

1.5 This standard is not intended to address all safety concerns (if any) associated with its use. It is the responsibility of users of this standard to establish appropriate safety, health and environmental practices and to determine the applicability of regulatory restrictions prior to use.

1.6 This international standard is based on internationally recognized standardization principles established in the “Decision on Principles for the Development of International Standards, Guidelines and Recommendations” issued by the WTO Committee on Technical Barriers to Trade (TBT).