SPECIAL PROCESSES – THE PROCESS OF PAINTING – cap. 5
Choice of paint, binders or resins for powder-cycle:
The coating products based powder are widely used in many industries, because, in addition to ensuring excellent performance and aesthetic good mechanical performance, allow a good reduction of costs (easy application, less product used, reduced waste). In addition to this, allow a high reduction of environmental impact (emissions, disposal) as these products are free of diluents or solvents additional, thus allowing a greater safety for operators.
The powder paints, contain resins, pigments and other additives within the single grain (particle) and are usually applied by electrodeposition and in a single pass.
Needing a high amount of heat to form the film, their use is not suitable for application on substrates sensitive to high temperatures.
The powder coatings can be divided into thermoplastics and thermosets.
The thermoplastic paints:
The thermoplastic powders dissolve and extend through the action of heat, do not alter their composition when they cool. Having a high viscosity, do not guarantee a high requirement for membership and are usually used for high thickness.
The thermosetting paints:
The powders are thermosetting resins that become solid at high temperatures as a result of chemical transformations.
Following its chemical structure assure a good adhesion and a application in thin layers.
The thermoplastic paints most common are those based on:
· Polyethylene resins;
· Polyvinyl chloride resins;
· Thermoplastic polyester resins.
The thermosetting paints most common are those based on:
· Epoxy resins;
· Polyester resins;
However, the resin being the main component is briefly describe some features of the binders most widely used for the composition of paint products of the cycle powder. Are discussed below those most commonly used.
Epoxy resins:
Are particularly resistant to chemical agents, detergents and acids in general while maintaining good mechanical properties.
Their use, however, we find him on products destined inside.
The most common application is performed with electrostatic guns crown.
Epoxy resins – Polyester
Derived from epoxy resins are widely used in any manner.
Modified, represent a good compromise to give the epoxy a good UV resistance and hence higher employment outside, guaranteeing the discrete mechanical properties of epoxy.
The most common application is performed with electrostatic guns crown.
In the next chapter we further the application of coatings with a powder cycle.

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