A Tacky Subject
October 2004
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Plate mounting product manufacturers offer some suggestions and tips to help smooth out the plate mounting process.
TRAPPED AIR BUBBLES. Plates lifting during printing. Damaged plates from residue. Constant press adjustments. Low print quality. … Plate mounting has potential to be a nightmare for some press operators, but help is here to overcome some of the stresses brought on by the simple act of plate mounting. packagePRINTING spoke with some plate mounting material manufacturers to find out some tricks and hints, and a few new products that may soothe a frazzled plate mounter.
Be gentle to your plates
Flexographic plates, although tough, do need some tender loving care when being mounted onto a cylinder or sleeve. Some mounting tapes offer cushioning support, which lends itself to faster startups, higher line speeds, and fewer press adjustments.
One such product line, Rogers R/bak® mounting tapes, offer cushioning support much different from other companies, according to Timothy S. Wilson, senior printing product specialist with Rogers Corporation. He said that many tape products use a closed-cell polyethylene material in their construction, which has the potential of breaking down during press operation. Wilson explained that the closed cells in the polyethylene material can be compared to balloons. After all of the pounding that the plate and material takes during the printing process, the cell walls tend to burst like a balloon, leading to print quality problems in the long run.
"Closed-cell polyethylene tapes will break down during the press run, creating more press adjustments, slower press speeds, and compromised print quality," said Wilson. "Using an open cell urethane, like R/bak, will provide the most consistent and the highest quality print results on the press."
Joe Prunier, strategic market manager, print industry for tesa tape inc., said if a printer is noticing differences in pinholing or dot gain in the same print job each time they print it, this could mean a problem in the density of the foam of the plate mounting tape. "Every plate mounting tape has a target thickness and a tolerance, and there are two ways of accomplishing this—either extrude the foam to very tight tolerances, or have foam cut or shaved to meet tolerances," Prunier said.
Cutting or shaving the foam can destroy the foam's cell structure, Prunier added, and may create soft and hard spots in the cushioning of the foam. His advice to plate mounters is to look for plate mounting tape with foam that is extruded, not shaved, to reach the desired thickness.
TRAPPED AIR BUBBLES. Plates lifting during printing. Damaged plates from residue. Constant press adjustments. Low print quality. … Plate mounting has potential to be a nightmare for some press operators, but help is here to overcome some of the stresses brought on by the simple act of plate mounting. packagePRINTING spoke with some plate mounting material manufacturers to find out some tricks and hints, and a few new products that may soothe a frazzled plate mounter.
Be gentle to your plates
Flexographic plates, although tough, do need some tender loving care when being mounted onto a cylinder or sleeve. Some mounting tapes offer cushioning support, which lends itself to faster startups, higher line speeds, and fewer press adjustments.
One such product line, Rogers R/bak® mounting tapes, offer cushioning support much different from other companies, according to Timothy S. Wilson, senior printing product specialist with Rogers Corporation. He said that many tape products use a closed-cell polyethylene material in their construction, which has the potential of breaking down during press operation. Wilson explained that the closed cells in the polyethylene material can be compared to balloons. After all of the pounding that the plate and material takes during the printing process, the cell walls tend to burst like a balloon, leading to print quality problems in the long run.
"Closed-cell polyethylene tapes will break down during the press run, creating more press adjustments, slower press speeds, and compromised print quality," said Wilson. "Using an open cell urethane, like R/bak, will provide the most consistent and the highest quality print results on the press."
Joe Prunier, strategic market manager, print industry for tesa tape inc., said if a printer is noticing differences in pinholing or dot gain in the same print job each time they print it, this could mean a problem in the density of the foam of the plate mounting tape. "Every plate mounting tape has a target thickness and a tolerance, and there are two ways of accomplishing this—either extrude the foam to very tight tolerances, or have foam cut or shaved to meet tolerances," Prunier said.
Cutting or shaving the foam can destroy the foam's cell structure, Prunier added, and may create soft and hard spots in the cushioning of the foam. His advice to plate mounters is to look for plate mounting tape with foam that is extruded, not shaved, to reach the desired thickness.
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