GCM 240 Chapter Notes - Chapter 1: Softwood, Cellulose Fiber, Cellulose
30 Sep 2016
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Document Summary
Sheet-fed offset presses can print on a wide variety of paper types. Quality of paper will affect the appearance of the printed images. Surface of paper should resist picking, free of dust and lint, and resist moisture. The main raw material for making paper is cellulose fibers. Cellulose fibres: short, threadlike structures from all plant matter. Four main sources of cellulose fiber used in the manufacturing of paper: softwood trees, hardwood trees, recycled fiber, rag, sugar cane, and bamboo. Hardwood and softwood trees are most commonly used sources: hardwood trees: poplar, birch, maples. Produces shorter fibers ~ 1 mm in length. Produces paper with greater bulk and surface smoothness: softwood trees: spruce, pine, fir. Produces longer fibers ~ 3 mm in length. Produces stronger paper (due to better interlocking of fibers) Size and shape of fibers vary with type of tree. Paper is made up of not only fiber, but also sizing materials, mineral fillers, and colour.
