US Patent 11339305 Substrate coated with non-stick coating resistant to abrasion and scratching

A substrate coated with a non-stick fluoropolymer coating is provided, the coating having excellent abrasion and scratch resistance. The coating contains: i.) a continuous primer layer adhered to the substrate containing a polymer binder, a first fluoropolymer and first inorganic film hardner particles, ii.) a discontinuous midcoat layer containing aggregate particles adhered to the primer layer and distributed discontinuously across the surface of the primer layer so as to reveal exposed areas of the surface of the primer layer, wherein a portion of the aggregate particles are in clusters, and wherein the aggregate particles contain second fluoropolymer and second inorganic film hardner particles, and iii.) a topcoat layer containing a third fluoropolymer adhered to the midcoat layer and the exposed areas of the surface of the primer layer at points where there is no midcoat layer.