High solid and Extrusion coatings are used for specialized papers, where chemical, gas or liquid resistance is necessary. High solid coatings are applied as a coating of monomers and are polymerized by UV or electron curing. Extrusion coatings are applied as a molten film of wax or polymer. Calendering Rolls Paper roll at the winder
After the foils, water is further removed using flat suction boxes. The suction boxes remove the majority of the water, changing the stock consistency from 2% to 20% fiber content. Above the first couple of suction boxes a skeleton roll covered with wire may ride on the top of the paper mat. This roll called a “dandy roll” compresses the paper, releasing any trapped air and improving the surface. The dandy roll can be covered with various wire patterns, which may simulate the forming wire and may have recessed or raised elements-designs imparting a watermark onto the paper. In areas where the watermark elements, usually a wire design, are above the surface of the dandy roll, fewer fibers are allowed to settle, and the paper appears light. If the watermark elements are below the dandy roll surface, more fibers are allowed to settle than in the rest of the paper, and the paper appears darker in these areas.
Security Paper is used to the unauthorized duplication of any document.
This is accomplished by placing A NUMBER OF SECURITY FEATURES into the base paper stock onto which the document is printed.
A document which contains only one feature, a VOID background for example, may be duplicated on some photo copiers without the word VOID showing up on the copy.
A security watermark such as used on Level TWO Document Security Paper, is virtually impossible to accurately photocopy or scan.