The invention of paper and the recording of this discovery has been attributed to Ts'ai Lun, a courtier in the court of Ho Ti, emperor of China in 105 A.D. , although there is recent evidence that papermaking actually preceded this date. The process of making handmade paper was kept a secret and it was only in the year 751 that the Arabs learned about it from Chinese prisoners taken in Samarkand. Papermaking reached Baghdad in 793, Morocco in about 1100, Spain in 1150, France in 1189, Germany in about 1320, England in 1494, and Pennsylvania in the year 1690. 1
There are a number of variations of the papermaking fiber pulping process which evolved in different countries. However, essentially, the pulp fibers from which paper is made are obtained primarily from the stems and inner bark (or flower, in the case of cotton) of certain plants which are made from cellulosic fibers. (Cellulose is a naturally occurring long chain polymer). The bonding material that holds these fibers together in the plant is called lignin, which is a complex natural organic polymer.
In order to separate the cellulose fibers from the lignin, the early papermakers retted (fermented) the plant stalks. The fermenting could be accelerated by the addition of milk. Depending on the plant, this process could take several weeks or even months. 2
Much later the use of chemicals such as soda ash and caustic soda were used to cook the plant stalks, thus dissolving out the lignin, which was washed away. These early processes evolved into modern day pulping processes which process wood chips. Today, however, the cooking chemicals used are recycled and/or burned for fuel.
Around 1838 Charles Fenerty, a Nova Scotian, is credited with producing the world's first usable paper from woodpulp made by a grinding process. Independently in Germany in 1844, F.G. Keller produced enough groundwood pulp to make paper when combined with 40% of the much stronger rag pulp. 3 Thus began the use of mechanical pulps to make much cheaper, but much less permanent papers.
Other sources of fibers for the early papermakers were cotton and silk (also cellulose) rags which were gathered from households by the "rag men" and sold to the papermills. Even hemp rope, old fishing nets and old sails were used. This was an early example of recycling.
In order to make strong paper with uniform "formation", the cellulose fibers and rags, etc. had to be beaten or macerated. Originally this was done by hand using a large mortar and pestle-like apparatus. Later, this was replaced by water wheel-driven mechanized stamping machines. (And much later, by motor-driven beaters and refiners). This process disintegrated the textile rags and broke open the cellulose fibers thus exposing many "fibrils", or very fine fiber particles which intertwine and hold together during the wet forming of paper.
Next time we will start to talk about making paper by hand.
Don't forget to send in your questions to Margaret Johnson!
1 Paper in the Making, G. Caruthers, The Garden City Press, Toronto, 1947
2 Japanese Papermaking, T Barrett, Weatherhill, New York, 1984
3 Making Paper, B. Rudin, Vallingby, Sweden, 1990