Printing Plates-I

Thermal Plates
Alongside conventional printing plate systems, thermal
plates have been developed for digital imaging.

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Packing and Cylinder Pressure

PRESSMAN TIPS  Packing and cylinder pressure seem to be the number one culprit in printing related problems. It is absolutely necessary for the press operator to check and maintain proper printing pressure between plate, blanket, and impression cylinders. Press manufacturers should be able to supply this valuable infor mation. Most of the time the packing information is located on a plate on the press or in the operating manual. How much pressure is too much? Most operators feel that is .004" squeeze is good, then .008" must be better, and if that doesn't work then an extra .002" - .004" will certainly help. This will without a doubt effect quality and production. Most presses should operate with .004" - .006" squeeze between cylinders. Any more than this can cause problems like dot gain, emulsification, bearing shock marks (streaks), poor register and fit to name a few. It would take several paragraphs to explain how each one of these problems ...
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Ink Mileage

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