Cast film is a premium grade vinyl that starts life as a liquid, it is then allowed to spread out to an extremely thin layer. Cast films do not have a memory and are stable, so do not tend to shrink. Because cast films are thinner and softer, they are easier to apply. Cast films conform over irregularities such as rivets and textures, making them the preferred films for the most exterior applications especially vehicle wraps.
Always choose a cast film for its quality and long life
Calendered films start life as a lump of plastic that is then flattened by being passed through two pressure rollers. Though not as high quality as cast films in demanding applications, film produced by this process can nevertheless be adequate in less demanding conditions. Calendered films come in two types: polymeric and monomeric.
Polymeric calendered films.
Polymeric calendered films have added polymers to reduce shrinkage. However, although they have developed significantly over the years, they still fall short of the stability and durability of cast films. Polymeric films fare much better in exterior applications than monomeric films but are not suitable for application over surface irregularities such as rivets and corrugations. For less demanding exterior work, polymeric films offer a workable alternative to cast. If there is any doubt as to which film to use, however, avoid risk and choose cast film.
- Monomeric calendered films.
The least expensive vinyl film is monomeric calendered. These films are not suitable for demanding exterior applications such as vehicle liveries or fascia signs. The face film of monomeric film is not stabilized so it will almost certainly shrink to reveal the adhesive beneath. Dirt will adhere to this revealed adhesive and will be clearly visible as a sticky, black outline around the lettering and other elements. The sticky black outline is usually only the start of more severe degradation to come. Eventually, the vinyl face film will begin to curl up and flake off like peeling paint. Monomeric films, therefore, are best suited to short-term exterior applications and interior work.