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Liquid Courage: Coating Technology for Print Protection

(February 2008) posted on Wed Feb 13, 2008

Liquid lamination offers graphics producers the ability to protect prints at a competitive cost and minimize waste and labor in finishing. Read on to find out more about the technology and the applications for which it is suited.

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By Ben P. Rosenfield

Roll coaters use their rolls to share the duty of moving printed graphics along and applying coatings to them. From there, the coated media must either be cured by photoinitiation (UV), by heat such as infrared drying, or by air drying, which takes the longest amount of time. Media transporters, often in the form of conveyors, are integrated into some models to carry freshly coated substrates to the drying or curing systems. As an alternative, graphics coated with water-based formulations may be carefully racked horizontally and allowed to dry. This approach is usually reserved for manual coaters. Harris says water-based coatings can air dry in 20-25 min.

Some of the recently introduced UV liquid laminators are able to cure at high speeds, sometimes at more than 100 ft/ min. They also can be designed with very conservative footprints. For example, the total length of such a machine may be less than 5 feet, including the conveyor, because the machine is able to process so much substrate so quickly.

The nature of the jobs and the quantities you accept ultimately dictate the type of liquid laminator you’ll need. If you print lots of banner graphics on scrim vinyl, or P-O-P images on fabrics, you may be better off with a water-based coating system. That’s because the material’s printed surface is covered in valleys that must be filled with the liquid coating for the lamination to be effective.

According to Jim Tatum, president of Advanced Finishing Solutions, running such textured materials through a UV liquid laminator isn’t the best idea because the machines lay down a thin coating layer at very high speeds. He says that given those operating parameters, the coating will never have the chance to fall into the depressions in the substrate’s surface.

“What happens is you get graphics that are partially coated and cured. That’s not going to do you well in bad weather and other elements that would cause the coating to get weak where it bonds,” Tatum notes. On the other hand, a waterbased liquid laminator would flood the textured substrate with coating, thereby ensuring that all of the valleys are properly covered.


Protective coatings and their applications


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