Varnish is a liquid that creates a shiny appearance on the surface it is applied, is known for its protective feature and provides strong adhesion on the surface it is applied. Thanks to this feature, it has been used in wooden doors, windows and home furnishings for years.
American doors are a door model produced from MDF type called HDF due to its structure. It has a high paint holding capacity due to the raw material from which it is produced. American doors are manufactured with a primer paint applied during production. They are sold by being painted with cellulosic or lacquer paint in the paint process.
Since American doors are manufactured with a primer and sold as painted, they can only be painted with cellulosic paint again. American door surfaces cannot be varnished. Since the primer paint is applied, the varnish you apply on the HDF will not penetrate the surface.