Non-stick coating system with thin undercoat of polyamide imide

A coated substrate comprising a substrate with a multi-layer non-stick coating, comprising an undercoat, a primer, and a topcoat, and up to one or more intermediate coats between the primer and the topcoat, wherein:

• the substrate is free of contaminants that would prevent adhesion of the undercoat,
• the undercoat is applied to the substrate and consists essentially of (on a weight basis after air drying but before baking) up to 8% surfactant, up to 20% fine-particle silica, the balance polyamic acid or polyamide imide, and has a dry film thickness in the range of 0.1-5.0 microns,
• the primer is applied to the undercoat and comprises perfluorocarbon resin and at least one of polyamic acid or polyamide imide, polyarylene sulfide and polyether sulfone and has a dry film thickness in the range of 2-15 microns, and
• the topcoat comprises perfluorocarbon resin.