Curing and drying systems

Abstract

Most surface coatings, including printing inks, are applied to metal substrates as liquids and need to be converted into dry adherent films. The exceptions are coatings applied as powders and film laminates, both of which are described in Chapter 3. In the case of powder coatings, which may be of the thermoplastic or thermosetting type, heat is required to fuse the powder particles into a continuous film and, in the case of thermoset materials, to effect a cross-linking reaction. In the case of laminates a free polymeric film is applied to one or both sides of a metal substrate, by the application of heat and pressure, with or without a separate adhesive layer. The heat element can be provided in different ways.