scope:

This specification covers the qualification and performance requirements of waterborne basecoat (BC) that is applied to rigid substrates.

Material Description. These basecoats are waterborne technologies and are components of rigid topcoat systems that are used in conjunction with 9984515 and 9986328.

Applicability. The waterborne basecoats are typically applied to dehydrated waterborne basecoat compatible primers per 9986328 which have been applied to the electro-coated metal surfaces or appropriately primed rigid plastics. Following the basecoat application, heated flash is employed to dehydrate the basecoat prior to solventborne clearcoat application per 9984515. Specific heated flash temperatures are dependent on supplier technology and heated flash design conditions needed to achieve prescribed dehydration levels. Following the 9984515 clearcoat application, the entire system consisting of the primer layer, basecoat layer and clearcoat layer is baked simultaneously in a single bake, as described in 3.2.

Remarks. Each combination of basecoat compatible primer (BCP), basecoat (BC) and clearcoat (CC) must be tested and approved as a topcoat system. The individual components are not interchangeable between suppliers unless otherwise tested. In addition, the topcoat system is part of the total coating system and must meet qualifications set forth in this specification and those shown on engineering drawings. Validation testing for plant-specific layering, ancillary materials and processing must be conducted before release.