How Paper is Made

No matter what method of paper production you use, whether this is by hand or through a paper machine, three basic steps make up the papermaking process.

First, the material used for making the paper is converted into pulp. This is done by cutting the wood into small chips then, using heat and a little chemical, these chips are soaked in water to break down the lignin in the plant's cell walls. If lignin is not removed totally, the paper will turn yellow when exposed to air and light. The end result of this process is a concentrated mixture of fiber suspended in liquid known as pulp. Once the fibers have been extracted, they may be bleached or dyed.

The next step is to dilute the mixture with water turning it into very thin slurry. This slurry is drained through a fine mesh-moving screen that transforms the mixture into a fibrous web and spreads out the fibers to form a sheet. This web is then pressed and dried into a continuous sheet of paper. A quantity of the pulp is placed on to a mould with a wire-mesh base to further drain water from it. Pressure may then be applied to remove any excess water.

The third step is to drain water from the sheets of paper further in order to create a usable product. This is done through pressing and drying. Although different ways of doing this are available depending on the process followed for the manufacture of paper, still the basic concept remains the same. Pressing the sheet of paper forcibly removes the water that is then collected by another absorbent material. When using a paper machine, this absorbent material is called felt. When papermaking is by hand, this is simply called a blotter sheet.  Drying the sheet involves applying heat or using air to take away any excess moisture. When completely dry, the sheet can then be cut into the desired size. Standard sheet sizes are prescribed by the International Organization for Standardization (ISO).