1. Film-forming polymers

1.1 Classification of film-forming polymers

Paints and varnishes contain as their main constituent a film-forming polymer (binder or resin) which, after curing, forms a continuous, adherent film with specific properties on the substrate. By definition, these polymers or macromolecules are organic or inorganic compounds with molecular weights between 300 and 10 ⁶ daltons. Several types of film-forming polymers are usually distinguished.

• Polymers of natural origin, including natural resins and gums, secretion products of plants (Landes pine gum) or insects (shellac) and fossil substances known as "Copal" (Copal gum Zanzibar, Madagascar, Congo, Kauri...).

  These polymers,...