摘要 |
A method of and apparatus for minimizing the problem of "fluting" or "corrugating" occuring in printed webs of light weight coated paper printed on both sides with thermosetting ink on heat-set web-offset printing presses resides in spreading the web in its width-wise direction as the printed web exits from the ink drying and heat setting oven of the press and passes over the web cooling chill rolls downstream from the oven, thereby to hold the printed web in a flat and smooth condition until it is cooled and the ink has taken a permanent set. Spreading the web prior to and during cooling allows the inks to thermoset in a flat state because the web is kept flat and free of flutes during thermosetting of the inks. The method and apparatus facilitate operation of the press at higher speeds and with lighter grades of paper than conventional, and provide for increased production efficiencies, lower costs, enhanced print quality, and access to new markets for web-offset printing.
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