Paper, until recently with the dawn of common computer usage, was the primary means of written communication for the developed world. In many nations, this is still the case. Annually, each American uses about 144 pounds of paper! This is an enormous amount, very little of which is recycled and most of which ends up in our ever filling landfills. Yet, do you truly know what paper is? Or how it's made? Or really, what it is made of?

Egyptian papyrus is not paper. Neither is the "rice paper" (Fatsia papyrifera, Araliaceae) of the Orient or the "mulberry paper" (Broussonetia papyrifera, Moaraceae) of the Mayans and Polynesians. (Incidentally, both rice and mulberry paper come from trees.) The Egyptians did write on papyrus, but as it is a material formed by many strips of papyrus leaves (Cyperus papyrus, Cyperaceae) being pressed together, it's not truly paper. The other two forms of "paper" were made by pounding various parts of the plants together, also not truly paper. So, what then, is paper?

Paper- separated plant fibers that have been matted together to form a sheet. Or, as stated by Dard Hunter (old grand master of paper making), "To be classed as true paper, the thin sheets must be made from fiber that has been macerated until each individual filament is a separate unit; the fibers are then intermixed with water, and, by the use of a sieve like screen, are lifted from the water in the form of a thin tratum, the water draining through the small openings of the screen leaving a sheet of matted fiber upon the screen's surface. This thin layer of intertwined fiber is paper." (Hand Papermaking, Inc., 1998)

Hmmm...sounds simple enough, until you start trying to separate the fibers. It is generally agreed that the first paper was made in China around 100 A.D. It was made of mulberry fibers and mixed with other fibers, like hemp and flax. The key difference between this first true paper and its predecessors was that the fibers had been separated from each other prior to forming a sheet. The technique spread through the orient, to Samarkand then into the Arab and Egyptian regions by 1000 AD. By 1100 AD, the technique had reached Europe, first in Spain and then spreading to Italy then the rest of now modern Europe. Parchment had been the surface of choice for writing prior to the paper introduction, but as demand for written materials increased, the supply of goat and sheep skins, used in the making of parchment, could not keep up. Thus, paper won the technology war.

Early on, plant fibers were separated by soaking and beating. This is a time consuming and often labor intensive process. In 1851, the first chemical methods were developed to separate fibers, especially wood fibers. This method used caustic alkali to boil wood chips in until nothing was left but a pot of fiber. In 1857 in Paris, the second chemical method was developed using sulfates. Still today, one of these two methods for separating wood fibers is used. (The above referenced from Hand Papermaking, Inc.)

So, now that we know what paper is and is not, what is fiber? Indeed, it is the same thing your doctor tells you you need to eat more of, it is present in bran muffins and in fruits and vegetables, in corn husks and tree leaves. Fiber is everywhere. Basically, fiber is cellulose. Plants make cellulose as a part of their cell walls and it is used for structural support. In animal cells, the border of a cell is defined by the plasma membrane. Plant cells, too, have plasma cell membranes defining their edges. But, as plants don't have bones, yet need structural support, they secrete various compounds to form an "exoskeleton" around each cell membrane. This is known as the cell wall. The cell wall varies according to the tissue and the amount of support needed by it. Some cells have only a primary cell wall, which is thin structure, anywhere from 1 to 4 micrometers (a micrometer is equal to ???), and is composed roughly of 9-25% cellulose, microfibrils, hemicelluloses (20-50%), pectic substances (10-35%), and proteins (10%). Primary cell walls have a high tensile strength and are porous. They are "stuck" together by the middle lamella. The middle lamella is made of pectic substances (yes, used to make jams and jellies) which is secreted by the cell between adjacent primary cell walls to "glue" them together. This is why plant cells don't fall all over the place, they are literally stuck together. If a plant cell has a future as a structural support cell or xylem tissue, then a secondary cell wall is secreted. Secondary cell walls are made of about 45% cellulose, 30% hemicellulose and 22-28% lignin. They are usually much thicker than the primary cell wall and the combination of the different components in it result in wood being one of the strongest material on earth. But, lignin doesn't exist only in the secondary cell wall. In cells with a secondary cell wall, lignin is deposited first in the middle lamella, then the primary cell wall, and finally the secondary cell wall, uniting all the factors of the cell wall complex. (Salisbury and Ross, 1992)

You may ask, which one of these cell walls can be and is used in making paper? The answer is, any and all. All plants contain cell walls, thus all plants have cellulose. Herbaceous plants in general have less secondary cell walls than do woody (wood is essentially dead secondary and primary cell walls). Plants that lack secondary cell walls also therefore lack lignin. Lignin in general is much harder and more brittle than cellulose and is therefore, not a good primary component of paper. It is also very difficult to remove from cellulose. But, who cares if there is lignin or pectin in paper? The presence of these substances causes the paper to yellow and crumble as the pectin and lignin degrade. Thus, for any kind of quality paper to be made, the chemicals can either not be present at all or must be removed first. Herbaceous plants don't have many lignin, thus making the separation of the cellulose fibers much easier than in woody plant tissue. Prior to the invention of chemical processing techniques, most paper was made of hemp, linen and cotton rags, all herbaceous plants. In modern times, wood pulp, specifically of conifer trees, is used for paper making due to its high availability. However, with the push for environmental responsibility, other options are and should be sought. Deforestation for lumber and paper is a big concern and rightly so. The chemical processes used to make paper from trees result in high levels of pollution (largely as a result of removing lignin and pectin), especially water pollution. If herbaceous plants were used on a large scale in modern paper plants, not only would deforestation due to paper no longer be a problem, the chemical output would be reduced due to lower levels of lignin in the plants and an important agricultural crop would be introduced to the farmers of this country. It is said, and is true, that trees are a renewable resource. However, they are renewable on a long term scale, often 10s of years, not the annual renewability of herbaceous plants. One of the plants proposed is the hemp plant, which is NOT the same as marijuana, but as of yet, is illegal to grow in this country. However, the processed fibers can and are imported from Europe for cloth and paper making and many paper hobbyists use hemp pulp. It not only is a long, strong fiber, it is also easy to grow and actually improves the soil in the farmlands.
 
 

Papermaking in the contemporary sense, is a science. The paper mill employs chemical engineers and many other scientists to run the facility and it is a highly regulated process. An excellent web page for the industrial method can be reached here. A very interesting and slightly off base virtual tour through a 400 year old British papermaking factory can be found at Wookey. A visit is highly recommended.

Paper can also be made at home. Indeed, there are many cottage industry crafters and hobbyists making paper at home. You can use preprocessed fibers bought from a supplier or process plant fibers yourself at home. A good paper pulp and supply catalogue is:

Lee S. McDonald, Inc., P.O. Box 264, 523 Medford St., Charlestown, MA 02129 Phone (617) 242-2505

A good resource for the hand-papermaking process is found here.
 
 

How to Make Paper from Plants:

Needed:

3 gallons of fresh plant material

lye (caustic soda) (can be bought in the drain cleaner section of the grocery store)

water

stainless steel or galvanized pan (large)

wooden spoon

Mould and Deckle

blender

vat
 
 

Cut plants into 1-2 inch pieces. Put some water into the pan, then add the lye. Stir with wooden spoon. (Always add the lye after the water!) Try to avoid splashing. If the liquid touches your skin, rinse immediately with lots of water. Add plants and add water until covered. Simmer for 1 1/2-2 hours or until the plant fibers feel soft. Rinse plants thoroughly. Strain through metal sieve. Scrub plants over sieve to release the fibers. Continue until all the fibers are separated. Place 2-3 tablespoons of fibers in to a blender full of water and blend for at least 20 seconds. The longer you blend, the finer the paper will be. This pulp can then be mixed with other fibers or recycled fibers. To size the paper fiber, add 1/5 teaspoon cold-water laundry starch with water and add to vat of pulp.

In a large vat, place an amount of water and blended fibers. The amount will depend on the size of your vat and how thick you want your paper. A deckle is the frame with metal screening nailed to it. This is the part that the paper sheet is formed on. The mould is the frame that gives the paper sheet its shape. The mould is always on top of the deckle with the metal screen between the two. To form a sheet of paper, put the mould and deckle together and pull up from the bottom of the vat (or further up, to change the sheet thickness). Once the deckle is above the water level, gently shake side to side and front to back to interlock the fibers and to ensure an even sheet of paper. Invert this on a felt (we used muslin) and remove the water from the back of the deckle with a sponge. The paper will now release from the deckle. Then, this can be dried between two felts or with an iron.
 
 

The fact of the matter is, while landfills are filling up and trees are being cut down, paper can be made from old paper. The quality can be the same as virgin paper. Consider these factoids:

- more than 500,000 trees per week are used to produce the two-thirds of newspapers that are never recycled.

- every ton of paper that is recycled saves 17 trees, 7,000 gallons of water, and 4,100 kilowatts of electricity.

- producing paper from recycled fibers reduces air pollutants by as much as 74% and water pollutants by as much as 35%.

- every ton of paper recycled leaves 3.3 cubic yards of free space in landfills.

Of course, as any economist will tell you, without demand, there is no need for supply. Recycling paper and other products is a great thing, but without buying products made from recycled materials, there is no need for recycling. So, do your part, recycle and buy recycled products.

To make recycled paper at home requires a lot of space, water and a blender. A good how to on recycled paper making at home is found here.
 

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last updated 7-25--2007