Machine papermaking is considerably more complex although its manufacturing process is quite the same. The first step in machine papermaking is the preparation of the raw material. The materials chiefly used in modern papermaking are cotton or linen rags and wood pulp. Today more than 95 per cent of paper is made from wood cellulose.
For the cheapest grades of paper, such as newsprint, groundwood pulp alone is used; for better grades, chemical wood pulp, or a mixture of pulp and rag fibre, is employed; and for the finest papers, such as the highest grades of writing papers, rag fibre alone is used.
But mainly, the essential procedures of machine papermaking are the same to those of hand papermaking. And those are America and Canada.
Most paper today is made on Fourdrinier machine which is a result of many peopleís efforts. Nicholas-Louis Robert invented the prototype of the machine. St. Leger Didot, who owned the mill where Robert worked, encouraged him to use the millís workshop in the development of the paper machine. Didot took the models created by Robert to his English brother-in-law, John Gamble, who made an improved version of the machine. This improved version drew the attention of the brothers Henry and Sealy Fourdrinier, who engaged engineer Bryan Donkin and built a new and further improved machine in 1807 which was THE FOURDRINIER.
The heart of the Fourdrinier machine is an endless belt of wire mesh that moves horizontally. A flow of watery pulp is spread on the belt, which passes over a number of rolls. A shallow wooden box beneath the belt catches much of the water that drains off during this stage. This water is remixed with the pulp to salvage the fibre contained in it. Spreading of the sheet of wet pulp on the wire belt is limited by rubber deckle straps moving at the sides of the belt. Suction pumps beneath the belt hasten the drying of the paper, and the belt itself is moved from side to side to aid the felting of the fibres. As the paper travels along the belt it passes under a revolving cylinder called a dandy roll. The surface of this cylinder is covered with wire mesh or single wires to impart a wove or laid surface to the paper. In addition, the surface carries words or patterns worked in wire; these are impressed on the paper and appear as watermarks that identify the grade of paper and the maker.
Did you know?
In handmade paper, the watermark patterns are fixed to the surface of the mould.
It takes 3 Ĺ barrels of oil and 7,000 gallons of water to process one ton of wood into paper.
Contents / Industry: Hand Paper making - Machine Paper making. _______________________________________________________________