GCM 240 Chapter Notes - Chapter 3: Calender, Complement Component 1S, Paper Machine
30 Sep 2016
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Document Summary
Before paper forming, pulp is mixed with water, with 99% water and 1% pulp. Water is drained through the moving wire screen, leaving the fibers on top. Fibers align with the moving wire, forming the paper"s grain direction. Wet/forming section: diluted furnish is formed into a mat of fibers, with water being removed by gravity/vacuum. Press section: most of the water is removed by pressing and suction. Drying section: remaining water is removed by evaporation from hot drying cylinders (at this point, moisture is 2-8%: the size press is located in the dryer section that applies the sizing material. After drying, paper web is calendered in a stack of steel rollers to achieve smoothness (machine-finish) Supercalendering: running machine-finish paper through the supercalender: supercalender: steel rollers alternating with cotton rollers running together. Improves paper whiteness, pick resistance, water resistance, ink holdout, paper opacity, gloss, and overall print quality. Usually paper is coated on both sides (cs2)
