The Granthams’ Guide To Overlaminating & Encapsulating Films
April 17, 20194 min read
All The Info On Sticky Stuff Designed To Protect & Serve!
As suppliers of production laminating machines, we often get asked questions about which media to use. What different mount films are available, outdoor versus indoor adhesives, and what’s the difference between over laminating and encapsulating films?
In this post, I’ll delve into the uses for encap and overlaminates and why they have two very different finishing purposes.
First, let’s start off with encapsulation films.
Encapsulation films range from 40microns to 250microns thick. They start at 600mm or so wide rolls for desktop machines up to 1530mm for wide width laminators. Available in matt and gloss versions, some operators put a gloss roll on the bottom laminator roller and a matt roll on the top (or vice versa) so it’s a simple task of feeding the print in face up or down to change the encap finish.
Regardless of whether a different finish is on either roller, encapsulation film is always used on both sides of the print.
Check your laminator has a heated top and bottom roller - encap film is applied at temperatures of up to 110degrees Celsius to melt the glue and produce a strong bond. The purpose of encapsulation film is to strengthen the printed material to create a much more durable finished product.
From membership cards to menus, catalogues to table cards, encapsulation provides a simple way of beefing up a paper print to make it fit for purpose, tear resistant and much more long-lasting.
Different end uses call for different encapsulation films. If the end product needs to be both lightweight and cost-effective, the standard films have a 1/4 construction. This means the film is made from 1 part polyester to 4 parts low-melt adhesive.
Needing something more bulletproof? A 1/2 construction film makes for a much more rigid alternative.
Encapsulation films can also be food use approved making for easy to produce deli counter price labels.
Be aware when handling encapsulated prints. They can be rolled up but rolling too tightly or attempting to fold and the film will permanently crease. It’s recommended that the print also has an ‘encap border’ on all sides as to prevent edge splitting, the film needs to be stuck to itself.
Now to the overlaminates.
Instead of being activated by heat like the encap films, overlaminating films work on laminator pressure and an adhesive glue layer.
Pressure on the laminator roller pushes the film onto the face of the print and the overlaminate is only applied to the one side.
Mainly available at around 1040, 1300, 1370 and 1530mm widths, there is a much wider range of finishes than with encapsulating films.
There are the standard matt and gloss finishes along with a crystal or ‘sandtex’ texture plus specialist laminates such as anti-graffiti, dry-wipe and even faux leather and canvas look products.
An over laminate’s primary function is to protect.
They first became popular as a way to enhance the lifespan and durability of prints made with water-based inkjet printers. An overlaminate created a waterproof finish, added UV light fastness, and offered different finishes.
As the industry moved from waterbased to solvent and eco-solvent printers, their use remains the same.
Even a solvent or latex print can scratch so the overlaminate will extend the life of the product by potentially many years.
As the textured face film to exhibition panels, a crystal finish will stop both accidental scuffs and unwanted fingerprints.
Floor graphic overlaminates can create imaginative retail displays with a textured underfoot feel and anti-slip properties.
Cast vinyl overlaminates applied to printed vehicle graphics will extend the lifespan of the finished printed product and help prevent any issues from overeager jet washing.
There are many specialist uses for overlaminating films. To find out more on what they can do for your business, get in touch.
When applying overlaminates, be aware that too much roller pressure can create a curl in the print, too little and the film won’t adhere uniformly across the print.
Many operators also use a little heat in the rollers - up to 30 degrees Celsius - to help the glue start working.
This especially helps when applying matt or crystal textured films as it evens out any possible silvering.The silvering comes from uneven pressure lines in the adhesive.
Solvent and eco-solvent prints need to ‘gas off’ for up to 24 hours before overlaminating. This ‘gassing off’ enables the solvents to breathe out of the print as part of the inkjet process, any overlaminate will prevent this outgassing and may bubble or contort.
Latex printers don't need this ‘gassing out’ period and neither do UV curable machines. UVC printers, however, apply the ink by building up layers onto the substrate.
These layers can feel like peaks and troughs depending on the ink load. I would recommend a high-coat weight overlaminate to make sure the thicker glue layer sits in the dips whilst still adhering across the full print.
If you’re unsure whether to use HCW laminates, try pulling at the edge of a standard overlaminate that's been applied to a UVC printed board. It’ll come off with ease as it won't have been able to stick to both the highs and lows of the printed surface.
Need to know more about which overlaminate or encapsulating film fits your requirement? Get in touch at firstname.lastname@example.org 01772 250207and we’ll help guide you down the right path.