摘要 |
Corona roller comprising a cylindrical base body and a roller cover of dielectric material, and method for producing it. The roller cover includes a layer of thermoplastic material, e.g. polyamide, applied onto the outer surface of the base body. Solid (powder) particles having electrically insulating characteristics are imbedded in the material matrix of said layer in the vicinity of the surface thereof in a form-locking manner such that merely a partial region of said particles protrudes from said inner layer. A hard, wear- and corrosion-resistant surface is formed at the outer side of the layer of plastic material, said hard, wear- and corrosion-resistant surface likewise having electrically insulating characteristics. For producing the corona roller, the layer of thermoplastic material is heated to a viscosity similar to that of honey. Preferably, a layer of oxide ceramic then is applied by thermal spraying, wherein the first powder particles thereof are shot into the heated layer of plastic material and subsequent particles form an outer functional layer. Alternatively, insulating particles of solid material may be dispersed into the heated layer of plastic material and may be ground thereby forming the wear-resistant surface.
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