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Print Preservation: A Look at Wide-Format Laminators

(October 2008) posted on Fri Oct 10, 2008

The laminator is your first line of defense when you need to shield and enhance your screen-and digitally printed graphics. Learn about the types of machines on the market and find out how a laminator can help you expand your capabilities and customer base.

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By Ben P. Rosenfield

Heat sources and cooling Most thermal laminators rely on a suspended heat source that runs through the nip rollers. The heater’s duty cycle involves bringing itself up to operating temperatures, heating the surrounding ambient air, and maintaining those temperatures. Contact heat sources are the most effective, according to Haan, because they are actually touching the inside surface of the roller assemblies. “The thermal recovery rate from the act of laminating is faster with such systems, and they also provide the capability of managing temperature uniformity across the roll face,” he says.

Maintaining an even temperature profile across the face of a roller is critical. In some roller configurations, where a single cal-rod heating element is suspended in the center of the roller, the journals, bearings, and all of the steel used toward the end of the rollers can act as a heat sink and draw heat out. Such an effect can lead to temperature variations and require the operator to push the temperature beyond its required level to compensate.

Thermal laminators generally feature a cooling apparatus between the pull rollers that maintain proper film tension and guide the laminating process and the laminating nip rollers. The cooling mechanism typically takes the form of chill rollers that pull excessive heat out of film and cool it to a flat state. The chill rollers are not internally cooled, but instead rely on a fan bank or group of blowers to help them dissipate heat.

Controls and adjustability The materials with which a laminator may be compatible are largely determined by its adjustability. The main factors to consider are the range of temperatures, material-feeding speeds, and media thicknesses supported by the unit and how these parameters are controlled.

In terms of controls, laminating equipment runs the gamut, from simple, analog systems with mechanical switches to advanced systems with touchpad controls and digital readouts. Many digitally operated systems can be used to program and store common job settings for easy recall. In the end, the type and number of jobs you plan to run will dictate the type of controller best suited to your needs.


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