By Denise Nathan
Do you need to over laminate your digital print? Lamination is beneficial for four main reasons.
1. Effect - Gloss laminates sharpen colours and contrast and give the illusion of a higher level of detail in the print. Matt softens colours and contrasts, is an excellent finish for hiding imperfections and ideal for interior applications to minimize the glare of in-store lighting. There are a variety of other finishes for various effects.
2. Protection - Laminates protect prints from scratches, chemicals, graffiti and other contaminants and make prints easier to clean.
3. Durability - UV inhibitors present in some laminates protect the ink and can prolong the durability and colour intensity of the inks.
4. Application- Lamination can give a print more rigidity which makes application easier.
CLEAR COATS /LIQUID LAMINATION VS FILMS
Clear coating and liquid lamination have been popular but is it the best option versus laminating with a film? Both processes have positives and negatives so you need to evaluate the requirements of your application.
The main advantage of clear coating is that you are not adding another layer of film, so for some applications like vehicle wraps it means you can conform the film more without cutting to relieve tension HOWEVER you need to be completely confident that the clear coat system you are using is compatible with the film. Also some clear coats will restrict conformability and have an adverse effect on the adhesive. If the graphic is exposed to regular abrasion then a clear coat/liquid laminate can quickly be eroded, exposing the ink and limiting the life of the graphic.
Using a film laminate gives you much better protection of the graphic from UV and abrasion. By laminating with the correct film you have the advantage of knowing the laminate is compatible with the base film. Film laminates increase the thickness of the graphic making for easier installation. Lamination can also give you different effects (gloss, matt, satin). Textured laminates can provide slip resistance for floor graphics and specialized polyesters can provide graffiti protection.
A critical aspect for successful lamination is to ensure the print is TOTALLY DRY. Drying before laminating is essential or the solvents will remain trapped and continue to attack the media. This can cause delamination of the laminate or adhesion problems to the substrate. While this sounds like common sense inadequate drying of prints is still very prevalent in the industry. As printers strive to meet customer demands the pressure for a fast output is compromising correct conversion procedures. One of the biggest causes of print failures in the market that I see is due to incorrect drying.
The other key to successful laminating is to use like with like products – Monomerics with Monomerics, Polymerics with Polymerics etc. There are exceptions of course e.g. Polyesters can be used to laminate PVCs. The problem is that different products expand and shrink at different rates. The adhesive is like a fluid layer in-between which allows for movement. If one layer moves differently then you can get problems like delamination or tunneling. Ideally you would use the same brand of product and follow the supplier’s recommendations. This will ensure compatibility and also ensure your film warranties remain valid. Some manufacturers may void warranties if other products are combined. This is not true of every manufacturer, however if there is an issue with the graphic performance it does make evaluation and testing more challenging and determining which brand was responsible more difficult.
By following these basic steps in the selection and conversion process you can eliminate any unnecessary risks.
Denise Nathan is Marketing Manager - MACtac in Oceania