Ralph McGinnis, age 14, of Somerset, New Jersey, for his question:
How do they make paper?
It seems that every few years we face a large or small shortage of paper. While this provoking situation lasts, we want to probe behind the scenes, hoping for sensible explanations. Naturally, the first step is to learn how modern paper mills produce their vast supplies. Maybe some of the answers to shortages are there. However, paper¬making has an age old history and some of the possible solutions may be hidden in the past.
The basic paper making ingredient is cellulose. And cellulose is the tough, fibrous material that plants create to build their boxy cell walls. The earth produces thousands of different plant species and at least hundreds of them produce cellulose that is suitable for making paper. In fact, about ten per cent of our paper supplies are manufactured from the cellulose fibers of plants such as hemp, jute and cotton and some is made from wheat straw or corn stalks.
The other 90 per cent is made from the woody fibers of trees ¬but it takes many years for a tree to grow big enough to be worthwhile. When forestry programs are neglected, there are not enough new trees to meet your paper needs. Since modern paper mills are designed to cope mainly with wood fibers, they run short of their basic ingredient.
Basically, all paper is made by chomping fine cellulose fibers into short lengths, mixing them with water and drying the soupy pulp in flat, matted layers. The first pages were made by Ts'an Lun of China, way back in 105 A.D. He used the inner bark of mulberry trees and allowed his soupy mixture to dry in flat sieves. Later, Chinese paper makers used old fish nets, rags and fibrous stalks of hemp.
For centuries, paper making was a slow operation, patiently done by hand. Linen, cotton and whatever fibrous materials were handy were mashed, mixed and dried to make paper. The first machines to make the work faster and easier were developed in the 1700s. The Dutch used a machine to shred rags. The French used a system of rollers to make it possible to dry and press larger batches of paper.
Modern paper making methods began in the 1800s when machines were invented to process wood fibers. Usually a modern paper mill is near a stream. Logs float to the door and lots of water is needed to convert them into paper. Machines stand ready to strip the logs and chomp them into chips. Digesters wait to mix and cook the chips with various chemicals. This breaks up the cellulose fibers into soupy pulp. Then the chemicals are washed out and bleaches and other substances may be added. Finally the wood pulp is rolled and dried, rolled and dried ¬to make never ending sheets of finished paper and paper products.
Paper making seems simple enough for anybody to make his own. But remember, our industrialized society uses 7,000 different kinds of paper and each of us uses about 450 pounds of paper products a year. One answer to the shortage is recycling. Old newspapers, magazines and countless other used paper products can be re used. That is, if we collect our waste paper and return it to a paper mill. In many cases, this economical re made paper is just as good as it was the first time around.