Posted on May 04 2014
Vinyls in general are manufactured in one of two ways;
"calendering" or "casting"
While at first glance these vinyl's appear similar their differences become apparent over time, and when applied in demanding environments.
The differences are in the manufacturing process and also in the plasticisers and stabilisers used. "Cast" vinyls are manufactured in a less stressed process than used in the manufacture of "calendared" vinyls. Cast films have the resin poured to form an extremely thin layer onto a very smooth surface before going through curing ovens. Cast vinyl generally have better dimensional stability, colour pigmentation, uv stability, and higher gloss levels.
"Calendered" vinyls are manufactured differently, using an "extruded" or "rolled" process which is more stressful on the PVC resulting in less dimensional stability in the direction it was rolled, it is however a lot cheaper than cast films. Calendered vinyls are either 'monomeric' or 'polymeric' dependent on the plasticiser's molecular structure.
"Monomeric" vinyls use plasticisers with a smaller molecule size so there is more molecular migration than in polymerics and will therefore have more effect on the adhesive and laminates used. These shorter chains of molecules also make the vinyl brittle when used in more demanding environmental conditions over time and resulting in shrinkage or "pulling".
"Polymeric" vinyls have longer molecular chains and larger molecules allowing less migration from the vinyl and so have less effect on the adhesive and will aid better longevity, flexibility and additional film stability with less shrinkage.
It is possible to buy monomeric or polymeric vinyls in either "calendered" or "cast" though it is pretty rare to get a monomeric cast film and most usually a cast film is a polymeric type of vinyl. The type of plasticisers used will have a noticeable effect on digital printing and how conformable the vinyl is. Polymerics are generally a lot better to print on than monomerics due to the surface plasticisers.