Lacking solvent, could they be called paints? As the old definition of paint began
to be strained because of the new developments, the term “coating” began to grow
in popularity. What didn’t fit the paint definition was conveniently called a
coating. A paint became “not necessarily a coating,” and a coating included all
paints and anything else that resembled paint but didn’t fit the old paint definition.
To confuse the issue further, once a paint or coating is applied and cured, the
two terms lose their slightly different meaning. Any applied and cured paint or
coating can be called either a paint or a coating. An applied and cured powder
coating film, electrocoating film or 100% solids coating film can be called a paint
film.
To simplify things, this chapter will discuss only “paint.” Powder coating,
electrocoating and 100% solids coatings will be discussed elsewhere in this book.
Paint is prepared by mixing a particular binder or binder combination, solvent
or solvent blend, additives and, perhaps, pigment or group of pigments together in
an exact way to produce a specific formulation that, when cured, will possess
certain properties. The cured film contains all of the ingredients present in the
liquid paint except the solvent, which evaporates during the paint application and
curing processes. A paint film very closely resembles a layer of plastic. In fact, a
totally organic paint film is identical in almost every way to plastic.