Most substrates require a primer only if testing shows need for it or where the sealant will be underwater after cure. Certain substrates do require a primer under all conditions.
وصف
Sikaflex® Primer-449 is designed to promote adhesion to porous substrates such as porous PVC, solvent-based enamel, PPG's fluorocarbon Duranar-finish, and certain plastics such as ABS and Plexiglass. Not designed for applications on concrete or cementitious surfaces.