PAPER
True paper has a long and rich history. It begins with Ts'ai Lun, who, in A.O. 105, requested the first patents for making paper. The actual inventor of paper is not known. Some of the earliest forms of paper were com posed of tangled silk that had been collected as a byproduct of the processing of silk cocoons for silk threads. Ts'ai Lun's paper was said to be made from old rags, hemp, fish nets, and tree bark. The recipe for making paper was a highly guarded secret within the Orient until A.DO. 751, when an Arab conquest resulted in the capture of some papermakers, who divulged their secrets. The Arabs, in Spain since A.D. 711, took the art there, and the first European paper mills were established around 1100.
By this time the process of papermaking was no longer very secret and had begun to spread rapidly through Europe. From Spain, its production moved to Italy. Fabriano established the first Italian paper mills in 1276, and is still making some of the world's finest papers. It was not until the nineteenth century, however, when papermaking machinery as well as a method for processing wood into wood pulp were invented, that paper became a common and inexpensive material. Prior to this time, papers were made primarily from rags and cotton, had great strength, and were relatively permanent. The conversion to ground wood as a raw material resulted in weaker papers that were impermanent. Much of the paper artwork, books, and numerous documents produced during the nineteenth century and the early part of the twentieth century are decaying rapidly and require conservation to preserve them. As the understanding of the causative agents for the breakdown of wood-pulp papers evolved, various paper refining techniques were developed and are continually being modified today.
The artists' paper that we know today started as a byproduct of the wallpaper industry. The first machine for making paper, invented around 1798 by Nicholas Louis Robert at the Essonne paper mills in France, enabled paper to be made in a continuous roll. Henry and Sealy Fourdrinier brought the invention to England and in 1807 developed it for commercial use in making wallpaper. Most artists' materials are derived from industrial products. It has only been since the middle of the twentieth century that significant research and development has been done on materials specifically for the artists' market.
THE CHEMISTY OF PAPER
PAPER is composed of cellulose fibers. Cellulose is a polymer of the sugar glucose and is used by plants to produce cell walls. Plant matter that has been processed to create a solution consisting of cellulose filaments suspended in water can be made into paper. A screen is passed through through the solution so that the filaments can collect on it and thus form a layer. This layer of cellulose fibers is then pressed and dried to produce a usable sheet of paper. The source of the cellulose fibers, and the degree to which that source is refined, determine the nature and quality of the paper produced. The two most important factors that affect the quality of paper are the presence of impurities and an acidic pH. Finished papers may contain natural impurities, such as lignins that have not been removed during processing, unnatural impurities, such as residual chemicals, like sulfites, not washed out during final processing, or such chemicals as alum that have been added during final processing.
Lignins, which are the combined glues that hold plant cells together, are undesirable in a finished paper product. They age poorly, tum brown, become acidic over time, are waterproof, and resist the natural bonding of cellulose fibers to each other. If lignins are not removed and are left in contact with the surrounding cellulose fibers in paper, their acidity will break down the cellulose and the paper will become brittle.
Lignins comprise 20 to 30 percent of wood, but only 1 percent of cotton fibers. Because of the high concentration of lignins in wood, papers made from wood pulp discolor and eventually self-destruct. Although there are methods for the removal of most or all of the lignins, unless the residual chemicals used in these processes are also dealt with, embrittlement and acidification will only be postponed. For this reason, wood-pulp papers are generally avoided for permanent artwork. Because it is nearly lignin-free, paper made from 100 percent cot ton is most desirable. The recently developed process for the removal of all lignins is being used at this time primarily to manufacture boards and storage containers used in archives, in conservation, and in museum-style framing.
Another major consideration in paper is its pH. The scientific symbol indicating the concentration of hydrogen ions in a liter of solution, pH describes the acidity, alkalinity, or neutrality of something. Water, which is composed of two atoms of hydrogen that are attached to one atom of oxygen, is designated with the symbols H2O or HOH. A very small number of water molecules, HOH, occasionally break up and reform. During the breakup, a positively charged H ion and a negatively charged OH ion are formed. The Hs are acidic and the OHs are alkaline. Since they are in equal amounts in water, water is said to be neutral-neither acidic nor alkaline. Water has been assigned a pH value of 7, which represents equal concentrations of acid and alkali. If the concentration of H ions becomes greater than the number of OH ions, then the result is said to be acidic, and a lower number is assigned. Each number represents a factor of IO ten times more or less acidic than the number above or below it. A pH of 6, for example, is ten times more acidic than water, and a pH of 5 is ten times more acidic than 6, or one hundred times more acidic than water. If the concentration of H ions becomes less than the concentration OH ions, the result is said to be alkaline and is assigned a higher number, such as 8, which is ten times less acidic than water (or ten times more alkaline than water). The scale ranges from 1 to 14.
pH SCALE
pH 1-2-3 5-6 - 7 - 8-9-10-11-12-14
<<acidic<< I >>alkaline>>
neutral
The more acidic a paper, the faster the cellulose will break down, resulting in a shorter lifespan. A number of factors can influence the pH of a paper. Residual acids from processing, rosin or alum sizing, fillers used to create bulk, oils used to make paper transparent, optical brighteners, atmospheric sulfur dioxide, and the presence of lignins can all result in a pH of 4.5 or lower. Recent study has shown that even the purest cotton papers will become slightly acidic, even though they left the mill at pH ranging between 6.5 and 7. This may be due to the nature of the paper itself, or because of exposure to air polluted with sulfur dioxide and oxides of nitrogen-common pollutants caused by the burning of fossil fuel-which turn water molecules into sulfuric acid and nitric acid.
To cope with the natural and unnatural acidification of paper, many manufacturers are resorting to buffering. Buffers are such chemicals as calcium or magnesium carbonate, which can absorb a significant amount of acid. Buffered papers are often slightly alkaline with a pH around 8.5. A pH moderately higher than 7 is not considered harmful in paper.
The two situations where pH information is vital is in the case of paper and boards used for archival storage and framing, and in watercolor papers. Materials used to help preserve artwork should have the highest standards. Although there is little reason for watercolor paper to meet all standards for archival use, it should be close to a neutral pH (neither acidic or alkaline) because many pigments used in watercolor are sensitive to significant change in pH. The white ness of watercolor paper is another important factor because as paper acidifies it usually yellows.
Although virtually all paper products used for archival storage and framing are buffered to maintain a nonacidic pH, only a few artists' papers are buffered.
With the exception of watercolor papers, it is generally considered unnecessary in papers made with 100 percent cotton because most 100 percent cotton papers will acidify only slightly and stop. It is becoming more commonplace to buffer wood-pulp art papers and boards to slow down, not stop, the discoloration and embrittlement process. The problem of maintaining a nonacidic pH with even 100 percent cotton watercolor papers is the need to add a size to reduce absorbency. Although Aquapel is a neutral size, it has not yet replaced the traditional alum/gelatin size. Alum is a combination of sulfates, which tend to acidify the paper, leaving it sometimes with a pH as low as 4.5. Exactly how much damage to a paper will be caused by a specific amount of acidity is debatable. It is clear that wood-pulp papers are more sensitive than rag or cotton papers because pulp fibers are shorter and are weakened during refine ment. Yet, recently, documents produced during the Salem witch trials on paper made from linen and rags were found in the basement of an old building. They were found to have a pH near I from centuries of rat urine, yet they were still flexible and readable despite considerable yellowing. The lesson here is that pH can affect permanency and quality but is not necessarily an indication of either.
HOW PAPER IS MADE
PAPERMAKING begins with the process of breaking down plant materials until individual cellulose fibers are obtained and are then suspended in water. A sheet of paper is formed by passing a screen through the suspension so that the individual fibers collect on the screen. The sheet of paper is then transferred to a mat where it is allowed to drain and dry. Pressure is often used to speed the process or to impart a particular finish.
The type of paper obtained can be influenced dramatically by such factors as the variety of plant material used, how the plant materials are broken down into fibers, how small the cellulose fibers are, the kind of screen used, how the screen is passed through the suspension, the kind of mat on which the sheet is placed, and whether the sheet is pressed. Other factors that influence paper variety are the use of chemicals, the addition of fillers or brighteners, the way in which the sheet is dried, and the polishing of the sheet's surface. All these variables make it possible to produce almost unlimited styles of paper. In the Orient, one can find more than a hundred varieties of paper made with the same plant material where the only differences in its manufacture are the way the screen is passed through the suspension and the average length of the fibers.
Handmade paper is often the least complicated method of papermaking. This method is so labor-intensive, however, that the cost of using the best plant sources often pales by comparison. Therefore cotton and rag fibers, which require little or no special treatment-chemical or mechanical-to reduce them to workable fibers, are commonly used. Today, sheets of cotton linters, made from the leftover short fibers collected from the cotton gin, are added to water and beaten in a machine similar to a blender. The level of concentration of fibers helps to determine the thickness of the paper. The suspension is transferred to a vat through which a flat, rectangular wire or bamboo screen can be passed to form the sheet. The fiber-laden screen is drained and the wet paper is often pressed before it is allowed to dry.
In mouldmade paper, the person holding the screen is replaced by a rotating screen cylinder, which forms a continuous sheet of paper. The individual sheets are produced by passing a stream of air or water through the wet sheet. Mouldmade paper is considered half handmade and half machine-made because people are still used to create the suspension of fibers as well as in the pressing and drying of the individual sheets. The cost of materials becomes more significant and occasionally results in the use of cheaper raw materials. Such materials require refining before use, as well as chemical additives to improve their appearance, all of which complicates the papermaking process.
The production of machine-made paper involves little human contact until the paper is purchased. The materials are the most significant cost factor in this type of paper production. Elaborate chemical and mechanical processes are often used to change poor-quality raw materials into a useful piece of paper. First, impurities are removed; then the chemicals used to purify the raw materials must be removed or neutralized. Often such additives as sizing and optical brighteners are required. Then a rotating cylindrical screen pulls the fibers from the suspension to form a continuous sheet of paper. Finally, this sheet is pressed and dried by other steel rollers. For some types of paper like bristol, additional sizing is added before drying and the surface of the paper is polished after drying. The primary disadvantage of machine-made paper is that most varieties are of low quality. The advantages of machine-made paper include price, the availability of some varieties, such as hard-surfaced bristol and paper boards, which could not possibly be made by hand, as well as the ability to produce large quantities
Sizing is the use of a glutinous material to fill up the pores in a paper's surface. Paper is composed primarily of cellulose. Cellulose possesses a great many "free radicals," a chemical term for atoms containing unpaired electrons. Free radicals love to attach themselves to water molecules. Therefore, when the cellulose of paper comes into contact with water, the water forms a temporary chemical bond causing the paper to swell to accommodate the increased volume. The purpose of a size is chemically to tie up a certain percentage of these free radicals and make them unavailable for water molecules. The more size, the less absorbent the paper will be, resulting in less buckling of the surface and less bleeding of color.
Animal gelatin or glues were early sizing agents. In the mid-seventeenth century, alum (potassium aluminum sulfate) was introduced to harden the gelatin sizing. Hardening the soft gelatin increases the surface tension and results in the color staying more on, and spreading less over, the surface. This allows the painter to work more slowly and achieve greater detail. By the nineteenth century it became clear that the animal gelatin aged poorly, and that the alum acidi fied the paper. These deleterious effects led to the unpopularity of animal-source sizes. Rosin (a residue collected from the processing of pine trees) was then introduced as a possible substitute, but it proved to be even worse for the longevity of art paper. In the recent past, vegetable gelatins replaced the animal gelatin because of their better aging characteristics. Efforts to deal with the acidic alum-sized papers through the use of buffers proved unsuccessful; alum requires a slightly acidic pH to attach itself to paper.
Today, a synthetic size, Aquapel, manufactured by Hercules, Inc., is replacing the traditional sizing agents because it possesses all the ideal characteristics of a hardening size without the disadvantages. Chemically, Aquapel is an alkene ket ene dimer. Dimers are chemicals with two chemically active parts and Aquapel has one area that is attracted to water and one that is attracted to oil. The part that is attracted to water attaches to the free radicals of the cellulose in paper and the other part repels water. The most important characteristic of this size is that it works without an acidic pH.
Most art papers are sized in one of two ways-tub or surface. Tub sizing is commonly used in handmade and mouldmade papers, where the whole sheet is dipped into a vat containing a size. This results in sizing equal on both sides. Surface sizing is done on machine-made papers, where the size is applied by roller to one side only; only the sized side is meant to be used.
Surface refers to the front and back, or top and bottom, of a piece of paper. The top of the sheet of paper is determined by the manufacturing. A piece of artwork is usually done on the top surface, that is, the side in which the most care has been taken, the surface to which the sizing has been applied. Some illustration boards and bristol paper are specially manufactured to have two identical working surfaces.
Tooth is a term that describes the arrangement of small peaks and valleys that the fibers form on the surface of the paper. The degree of difference between the peaks and valleys determines how the pencil or pastel will be caught and how the graphite or color will settle on the surface.
Weight describes one aspect of a paper's quality. The "basis weight" of a paper is based on the weight of 480 to 500 sheets (500 sheets equal one ream) of a paper in its standard size at a temperature of 75°F and a humidity of 50 percent. For example, 140 lb. watercolor paper-a typical artists' paper-indicates that approximately 500 sheets of this paper in its standard size, 22" X30", would weight 140 pounds. The standard size used for most print paper basis weight is 24" x 36". It is particularly difficult to compare weights of art papers to commer cial print papers because of the difference in standard sizes.
CHARACTERISTICS OF PAPER
THERE ARE SEVERAL TERMS that are often misused in describing paper. Durability, for example, is often confused with permanence, formation with grain, and finish with surface. Understanding the applicable terms will greatly improve your chances of getting what you want when buying paper.
Acid-free is a term used to indicate that a paper or board, when it leaves the factory, has a pH of 6.5 or higher, which indicates that there is little or no acid that can accelerate aging or deterioration. However, "acid-free" does not mean that the paper or board is guaranteed to remain in this condition or that it is free of any other undesirable chemicals. It also does not mean that it is safe to use the paper or board for archival storage or framing. "Acid-free" is a label some times used in misleading ways by a few manufacturers to imply permanency when it does not exist.
Conservation is the repair, restoration, and preservation of documents, objects, and artwork with the intention of preserving them permanently.
Deckle refers to a wooden frame used in the papermaking process and to the irregular edge on the paper produced by the use of that frame. In papermaking, a screen or mould is passed through a suspension of pulp to form sheets of paper. A deckle is a separate wooden frame fitted over the papermaking mould to pre vent excess pulp from spilling over the mould as it is lifted from the vat. A deckle edge is formed when a small amount of pulp seeps under this frame, producing an irregular edge on the paper. This deckle edge is often left un-trim med. Handmade papers have four deckle edges because each sheet is made individually and the water is allowed to drain from the mould in both directions. Mouldmade papers have two deckle edges and two tom edges because one continuous sheet is formed and the water is allowed to drain in one direction. The one long sheet is later tom into smaller sheets, which accounts for the two tom edges.
Durability is the ability of a paper to retain its original qualities under use. Most print papers, for example, do not have a durable surface and will be ruined by erasure, but bristol paper is very durable because it will maintain its surface qualities under repeated erasures. Durability does not necessarily indicate perma nency. The American Society for Testing and Materials defines durability in their publication ANSI/ASTM D-3290 as "the ability of a paper to resist the effects of wear and tear in performance situations. For example, paper currency should be made durable, but permanence is not a problem."
Fillers include such materials as kaolin (clay), calcium carbonate, and titanium dioxide, which are used to fill the pores on the surface of papers and boards to make a paper whiter and more opaque, as well as to give bulk. The more filler that is used, the less fiber there will be, and it is the fiber that maintains the strength of a paper or board. Today, it is becoming increasingly common for manufacturers to load up ground-wood boards with calcium carbonate to buffer them against the significant acidity that develops as the relatively unrefined pulp ages. Too much of this chalk will result in a great sensitivity to changes in humidity, which can cause severe warping. If such a board gets wet, the chalk dissolves and the board can easily fall apart.
Finish is the condition of the surface of a paper. The terms used to describe the finish of drawing papers and illustration boards are similar to those used to describe watercolor papers and boards, but refer to different finishes.
In the case of drawing papers and illustration boards, the terms "hot press," "plate," or "smooth" refer to a surface that is as slick as glass with virtually no tooth. This type of finish is produced by pressing the paper through hot rollers. The terms "cold press," "kid," "vellum," "regular," and "medium," refer to a surface that ranges from a barely detectable tooth to the feel of a medium-grade sandpaper. "Rough" refers either to an irregular bumpy texture of the surface, or to a laid surface that is characterized by lines caused by the way the screen was sewn to the mould, like an impression of Venetian blinds.
In watercolor papers, "hot press" or "smooth" refers to a surface like that of a "vellum" or "cold press" drawing paper. Hot-press watercolor paper is not formed by pressing with hot rollers, but by the using of a fine wire screen to collect the fibers. A cold-press watercolor paper is formed by pressing the still wet paper with a textured surface like a felt mat, giving the paper an irregular surface. This watercolor finish would be equivalent to a "rough" finish in a drawing paper. "Rough" in watercolor paper is an exaggeration of "cold press." A "laid" surface finish is determined by the pressure and the grain of a wire grid against the surface of the paper.
Formation is determined by the manner in which the fibers collect upon the screen during manufacture. For example, when "wove" paper is held up to the light, the formation of the fibers appears uniform. When the same is done to an inexpensive bond paper, the formation will appear mottled.
Grain is evident in machine-made and mouldmade paper. The fibers tend to align themselves in the one direction that the wire screen used in the machine process pulls them from the water. This gives the machine-made paper more strength in one direction than another. In handmade paper, the fibers are pulled more slowly and they are lifted up and out, without directional preference. Handmade papers, therefore, have no grain.
GRS/m2 is a unit of measure for the weight of paper in the metric system. It is the weight of one square meter expressed in grams. A 140 lb. 22" x 30" watercolor paper is equivalent to 300 GRS/m2.
Handmade Papers are usually made of cotton or Oriental fibers. Strong chemicals are not used because these fibers do not have to be treated as wood does. The hand process of lifting the fibers from the water allows the fibers to align in all directions and interlock among themselves. This gives handmade papers great strength. When this type of paper gets wet, it will expand evenly in both direc tions with minimal buckling and warping.
Mouldmade Paper is halfway between handmade and machine-made paper. When making mouldmade papers, the individual screen used in handmade paper to pull the fibers from the water is replaced by a rotating screen. It slowly pulls the fibers from the water in a long continuous sheet. Individual sheets are made by passing a stream of water or air at intervals across the continuous sheet while it is still wet. This creates a weakness where each sheet can be gently torn free after drying.
Permanence refers to the length of time materials will maintain their original integrity. Materials that will not maintain their original integrity for a minimum of twenty-five years are not considered permanent. Materials that will maintain themselves for fifty to seventy-five years are considered relatively permanent if handled with care. A life expectancy from seventy-five to one hundred or more years is considered permanent. Materials that have shown little or no deterioration within seventy-five years will probably continue to remain in good condition for some time longer. The permanency of paper can be reduced by the presence of wood fibers, alum or rosin sizing, residual chemicals from bleaching, traces of iron and cop per from the water used in processing, exposure to sulfur dioxide or nitric oxide, and a pH of 5.5 or less.
Ply refers to one sheet of paper that is bonded to another of the same kind. For example, two-ply bristol is made of two one-ply sheets laminated together.
TYPES OF FIBERS
IN THE WEST, paper is generally made from wood or cotton or a combination of both. The way the fibers are chemically treated during the manufacturing process affects the appearance and the durability of the paper. The most suitable papers for permanent artwork are those made from cotton. Though some people believe that a paper is safe if it is at least half cotton fiber, only paper made of 100 percent cotton fiber is recommended for artwork that is expected to last for decades. Papers derived primarily from wood pulp, even pulp that is treated or buffered, are best used only for printing, graphics, or student purposes.
In Oriental papers, three types of fiber are commonly used-kozo, mitsumata, and gampi. These three fibers, used alone or in combination with each other. are the basis for the largest variety of papers in the world today. When used without fillers, these fibers produce durable, permanent papers, often of great beauty.
Ground Wood
Wood that is ground into a pulp without any additional purification is called ground wood. All the impurities-lignin, resin, and hemicellulose-remain. Paper made from ground-wood pulp is the least durable and the least permanent, and has the poorest appearance of all papers. However, the paper is more opaque than most and absorbs printing inks well. Since paper of this type is also the least expensive, it is popular primarily among printers and schools. News print, construction papers, oak tag, newsboard, chipboard, railroad board, and oatmeal paper are among the many ground-wood papers. It is my opinion that this type of paper should never be used as a primary ground for permanent artwork.
Chemically Treated Wood Pulp. In an attempt to improve the appearance, durability, and permanence of papers derived from wood, a variety of chemical treatments have evolved to make lignin soluble for easy removal and to separate the wood pulp into individual fibers. In 1851, a treatment using caustic soda (sodium hydroxide) was developed, which resulted in a pulp referred to as "soda pulp." This treatment increased bulk, but weakened the fibers. During the 1870s, a treatment that reduced the weakening of the fibers involved the use of sulfur dioxide and bisulfate, forming a "sulfite pulp." This method significantly reduced the lignin content to between 2 to 5 percent, which could be further reduced through bleaching and thorough washing. This pulp was given the name "alpha-pulp." This type of treatment is used today to produce the better-quality wood-pulp artists' paper.
The sulfate process developed by Carl Dahl in 1884 is the process used today for the production of most paper products in general use. It is more efficient than the sulfite process, which did not remove or break down wood chips, so they had to be removed before processing. This is not necessary in the sulfate treatment; however, the resultant pulp is much higher in impurities that resist bleach ing. The sulfate process produces a much stronger fiber and is often referred to as the Kraft process-the term "Kraft" is derived from the German word for strong. Although this process produces a stronger fiber, it is also much rougher and less suitable for use in the production of artists' papers.
Although sulfite, or alpha-pulp, papers are compared to cotton papers, they have neither the quality nor the permanence that only cotton papers have. The sulfite papers are a tremendous improvement, but, in most cases, the lignins are replaced with a lesser evil-the natural resins and chemical residues left over from processing. These are rarely dealt with, and must be before this pulp can be considered an equivalent to cotton. Ground-wood pulp papers have a lifespan of only a few years before embrittlement and yellowing take their toll. Sulfite papers are a vast improvement since it usually takes between one and three decades before the residual chemicals and the remaining natural resins produce significant yellowing and embrittlement.
A distinct advantage to sulfite is its moderate cost compared to cotton. A wide selection of papers are made from this pulp, including drawing, tracing, layout, bond, colored, decorative, and watercolor papers, and boards for illustration, mounting, and matting. This type of paper is fine for artwork that will be reproduced and the original may be sacrificed, but it should not be used for original artwork that will be considered an investment.
Chemically Treated and Buffered Wood Pulp is simply chemically treated wood pulp with the additional enhancement of a chemical buffer. The buffer keeps the paper made from this pulp looking better longer because yellowing will not occur until the buffers are exhausted. Buffering will also help to main tain the color quality of pH-sensitive inks, dyes, and certain watercolor pigments. Drawing and watercolor papers made from this type of pulp are being introduced by only a few companies, including Seth Cole, Rising, and Pentalic, but are nevertheless widely distributed.
Chemically Treated, Lignin-free, Buffered Wood Pulp is the result of a new process in which, it is claimed, all the undesirable natural residues and chemicals used in processing have been removed so that a pure cellulose pulp remains. This pulp is then buffered for extra safety. This is a costly process and if this pulp were used only to make a cotton paper substitute there would be little recognizable saving. In the case of museum boards, however, which are expensive partly because of the large amount of cotton fiber used, the savings may be as high as 25 percent when substituting this type of pulp for cotton. Currently, this pulp is being used primarily to produce a less expensive board for use in archival storage and framing.
Cotton
Cotton is virtually pure cellulose fiber, which has a natural resistance to deterioration and to many forms of chemical attack. Cotton fibers range in length from ¾ to 1½ inches. The longer fibers are separated by the cotton gin for use in the manufacture of textiles. The shorter fibers left in the gin, which are called cotton linters, are collected separately and used to make cotton papers and boards.
Papers made from 100 percent cotton are among the most permanent, most durable, and strongest. They possess all of the most desirable characteristics and all the best drawing, watercolor, charcoal, and tracing papers and the finest museum and illustration boards are made from 100 percent cotton fibers. Papers and boards made of 100 percent cotton fiber are among the most expensive. Keep in mind that many 100 percent cotton tracing and visualizing papers are impregnated with oil or chemicals, which can dramatically reduce their lifespan.
Rag and cotton are terms that today are virtually interchangeable. At one time, rag meant cotton taken exclusively from cotton textile remnants. Very few cotton papers are still made from rags, either entirely or partially. Fabriano's Roma paper, which is said to have been used by Michelangelo, is still, however, made of 100 percent rag. Strathmore's Artist Bristol is also still made of rag.
The difference between true rag papers and cotton papers made from linters is that the rags have the longer cotton fibers and the weaving seems to add strength. The symbol of quality is still a paper that is made from 100 percent cotton rags. That is probably why people prefer to call both cotton linter and cotton rag papers "rag."
Cotton and Wood
The larger the ratio of cotton to wood, the better the paper will handle and age. Most artists and conservators do not consider a paper with less than 50 percent cotton safe for permanent artwork. Owners of some paper mills of long standing, as well as some government guidelines, claim that paper made with at least 50 percent or more cotton fiber is safe. In Europe, most fine art papers have some refined pulp but the majority of the 100 percent cotton papers produced there are sent to the more extravagant Americans. I have yet to find an art restorer in this country, however, who will vouch for a paper that contains less than 100 percent cotton fiber.
Kozo, Mitsumata, and Gampi
These are the most common fibers used in making Oriental papers. Only the inner bark, or bast fiber, of Broussonetia kazinoki for kozo, Edgeworthia chrysantha for mitsumata, and Diplomorpha shikokiana for gampi, is used to make paper. When these fibers are used without wood pulp or other fillers, they are as permanent as cotton and, in the case of gampi, even more permanent.
Kozo, known in North America as mulberry, makes the strongest and most dur able of the Oriental papers. It has the longest fibers, will not shrink or expand when wet, and produces a paper with an uneven surface. This fiber is used alone to make paper and is added to other fibers to give them additional strength and durability.
Mitsumata is traditionally described by the Japanese in what they feel are female terms. They say it is the most beautiful, softest, most absorbent, and the weakest of the three fibers. It is often used to balance kozo fibers, which are described in male terms, to increase the absorbency, even the surface, and add beauty to a paper.
Gampi is described by the Japanese as having both male and female characteristics. Its fibers are long, thin, somewhat shiny, and very tough. The fibers are so durable that paper made of gampi is referred to as "paper cloth." Gampi paper is smooth, lustrous, and has its own natural chemical resistance to paper eating insects. It is nonabsorbent, damp-resistant, and may well be the most permanent paper in the world. The best paper is made from uncultivated plants, but the plant is rare because it was overused to the point of near extinction. Most available gampi papers are made from a species of the plant found in the Philippine Islands and processed in Taiwan.
Many Oriental papers available in the West are made from one of these three fibers. They are called Japanese papers, or Japanese-style papers, even if they are made in another country.
Tan-hi is the Chinese version of kozo fiber and is the primary ingredient in such traditional Chinese papers as gasen. Today, tan-hi is more commonly referred to as tampi.
TYPES OF PAPER
MANY DIFFERENT KINDS of paper are created for a wide variety of applications, including painting, drawing, graphics, printmaking, and calligraphy. Papers are available in an extensive range of sizes, thicknesses, and finishes, as well as in differing degrees of quality, permanency, and durability.
A particular type of paper can often be used for another purpose. Print papers, for example, can be used with acrylics, and many graphics papers are ideal for drawing. Keep in mind, however, that certain papers have poor aging characteristics and should not be used for permanent fine artwork.
This section explains the various types of paper and their many uses.
Watercolor Paper
Oriental watercolors and watercolor papers have been around long before Ts'ai Lun patented papermaking in China in A.O. 105. Western watercolor papers, as we know them today, were developed during the second half of the eighteenth century and are, therefore, a relatively modem achievement. James Whatman paved the way for the development of watercolor paper when, under commission in the late 1750s, he replaced the traditional coarse laid wire screen of the paper making mould with a wire screen so fine that it was called "wire cloth." This allowed for an even formation of the pulp fibers without any textural impressions left on the surface of the newly formed paper. This new style of paper was called "wove" paper and was primarily developed for printing. Whatman found that various textures could be imparted to this textureless paper. He discovered, for example, that when felt blotters of various textures were applied to the still wet paper surface and pressed, impressions of those textures were imparted to the paper.
Whatman made paper available in three finishes-"hot press," "not" (which meant "not hot press," and has come to be called "cold press"), and "rough." During this time, watercolor papers were still classified as drawing papers. Whatman has been credited with the adaptation of the "hard size" (alum-gelatin sizing) for use in watercolor papers. Sizing is particularly important in these papers because it allows the color to stay on the surface as the water sinks in. This gives watercolors their brilliance, which would be lost if the color were to sink below the surface with the water. An additional benefit is that the color can be reworked because of its accessibility on the surface of the paper. Arches watercolor paper has retained its popularity because of its "hard size" as well as its double sizing, both of which permit erasure and repeated washes. The heavily sized paper gives excellent control of watercolors.
Several manufacturers have attempted to resolve the problem of acidity due to alum hardening by simply not using alum. This approach produces a watercolor paper that is not popular with artists using traditional watercolor techniques. Watercolorists who do abstract expressionist work, however, often prefer the softer look that colors have on the surface of this type of paper.
Strathmore's 100 percent cotton watercolor paper has the new synthetic sizing called Aquapel, which can be buffered. (Eventually all fine watercolor papers will convert to this kind of sizing.) Strathmore's paper has two deckled edges and two cut edges, which makes it less popular among watercolorists who like to use the whole sheet and prefer to show four deckle edges in framing.
Whatman, Saunders, and Strathmore papers, as well as Fabriano and the Royal Watercolor Society paper, are still among the world's finest. Today's watercolor papers come in many different sizes, weights, and packages, such as pads and blocks. There are still only three categories of finishes available, but each category varies from brand to brand, allowing somewhat more choice for the artist.
Hot press has a smooth vellum surface with a very fine tooth. This finish is excellent for soft drawing materials, pen and ink, brush linewock, wash, and airbrush. This type of paper is not as popular for traditional watercolor techniques.
Cold press, or semirough, is the most popular finish and is especially good for beginners. Cold-press finish is excellent for traditional watercolor technique and, because of its moderate texture, will handle some detail. This finish is also excellent for charcoal, pastel, and paint sticks.
The purpose of the texture in watercolor paper is to create a sense of depth. One of the . ways to accomplish this is by varying the ways that the finish receives the color. A wet wash will cover the peaks of the finish as well as penetrate the valleys. One color will tend to look like two because of the differ ence in the ways that the light strikes the peaks and the valleys. When a second, drier wash is applied, it will tend to cover the peaks without penetrating the valleys, and will also miss some of the peaks. A painter can rapidly develop many textural effects with a minimum of effort. How the individual artist devel ops this technique is what makes this simple medium so versatile. Some experi mentation with styles of cold-press finish, such as irregular versus laid, should be done to determine what is best for you.
Rough finish has pronounced peaks and valleys; even wet washes tend to be speckled with some spots of white showing through. This finish is not for beginners, but unfortunately for them, most of the less expensive watercolor papers are available only in a rough finish. Many people give up watercolors only because they started with this finish. It takes advanced skills to handle rough finish successfully. The large peaks and deep valleys tend to produce errors that are difficult to hide. When the finish is used by an experienced watercolorist, however, the results can be amazing. Rough finish can be used effectively with acrylics, paint sticks, and some pastels.
Watercolor paper is packaged in several forms: pads, rolls, sheets, and water color blocks. A watercolor block is a stack of watercolor paper, betwen 90 and 140 lb., that is gummed together at the edges, making it possible to do a paint ing without prewetting and stretching the paper, as is usually required for papers of weights under 200 lb. After the painting is completed on the watercolor block it is allowed to air dry, without the help of the sun or a blow drier. Air drying eliminates the risk of splitting the gummed binding that holds the paper together. Arches watercolor paper is the brand most readily available in sheets, rolls, pads, and watercolor blocks. Arches paper is mouldmade in France only during certain times of the year because the water from the river used to wash the paper becomes muddy during the winter. This accounts for the slight variations in whiteness from batch to batch as the water begins to change. Arches comes in the largest variety of weights, sizes, and packaging of all the watercolor papers available in North America. The weights for 22" x 30" range from 90 lb to 400 lb. Sheet sizes range up to 40" x 60". Arches has recently introduced an excellent student-grade paper called Archette. It consists of 25 percent cotton fiber; the balance is alpha pulp, and is 270 GRS/m2 or 127 lbs. in 22"x30". At the present time, Archette is only available in cold press finish. This paper is significantly less expensive than Arches 100 percent rag version, yet its handling characteristics are almost identical.
Fabriano also makes a wide variety of watercolor papers. This company is particularly known for its Esportazione series, the finishes of which are quite rough. This paper is one of the few entirely handmade 100 percent rag water color papers available today. Fabriano also produces a watercolor paper named Artistico, which is a mouldmade paper of 100 percent rag and is more affordable than the Esportazione. The 300 lb. rough in the Artistico series is said to be produced on an especially slow-running papermaking machine, which allows the water to drain slowly. This process creates a paper with characteristics close to those of a handmade paper.
T. H. Saunders watercolor paper has undergone a number of changes in the company's attempt to make a more archival and better-quality paper. The current product is quite good and is certainly less likely than most to acidify with age. This may also be said of Strathmore watercolor paper. Canson Mi-teintes, which comes in thirty-five colors, was originally developed as a lightweight watercolor paper, but today is used more often as a pastel paper. It is currently only 66 percent rag, and buckles considerably when wet. Most of these companies make both mouldmade and machine-made papers, with different grades of pulp and qualities of finish.
PRINT PAPERS
Some print papers are used for drawing and painting. Like watercolor papers, print papers are available in a range of sizes, quality, and content. They are handmade, rnouldmade or machine-made. The two important differences are that print papers have a softer surface and contain little or no sizing. This makes them ideal for printmaking but, in most cases, undesirable for painting and drawing. Print papers in general are not as durable, thus the surface finish will not take erasure or hard drawing materials. The absence of sizing causes water colors to sink in and bleed outward, resulting in a soft, dull look. These characteristics can, however, be used to advantage with such materials as soft colored pencils or acrylics, or for Oriental-style watercolor.
Some of the most popular print papers are Rives BFK, Arches, Copperplate, and German Etching (75 percent rag). Arches and Rives come in a limited variety of shades. A category of print papers called "proof papers," are usually wood pulp and have a harder and more durable surface.
DRAWING PAPERS
Any paper that has enough tooth to bite off sufficient particles from a drawing material, such as graphite, to form a visible mark could be called a drawing paper. However, to be considered good, a drawing paper must be durable enough to take repeated erasure without serious damage to the surface. It should also take ink without bleeding or excessive absorption.
In watercolor painting, the brush is the most important component; in oil painting, it is the paint; in drawing, it is the paper. Each artist should make his or her own experiments and comparisons among the varieties available in the major categories of drawing papers-bristol, charcoal/pastel, drawing/sketching, bond, and graphics papers. Even a simple pencil line will appear totally different on different brands of the same type of paper.
This category is broken down into five basic groups: bristol, charcoal and pastel, drawing and sketching, bond, and graphics paper.
Bristol is the strongest, most durable, all-purpose drawing paper available. It has a very hard surface that is heavily sized, polished, and compressed. It comes in two finishes, plate and vellum, and in several thicknesses.
Plate Finish is as smooth as glass, is especially good for pen and ink, and allows flat and even washes. Airbrushing on this surface gives a very crisp look, but the finish is too slick for colored pencil, charcoal, pastel, and very soft pencil. Vellum finish is excellent for all pencil, colored pencil, medium to hard charcoal, hard pastel, and oil pastel. It is also excellent for washes, gouache, pen and ink, and airbrush when a fine texture is desired. Some care must be taken with this surface to protect it from the natural oils from your hands, which can be transferred to the surface, affecting the absorbency and the bite of the tooth.
Bristol is usually made so that either side may be used, although there may be slight differences in the finish between the two sides. Strathmore's 100 percent rag Artist Bristol is considered the standard to which all others are compared. This bristol is still made only from 100 percent cotton cloth trimmings, which helps to give it its tremendous strength. But, because of the widespread use of cotton-synthetic blends in the garment industry, there is an increasing shortage of raw materials for production of this paper. Strathmore is currently developing a process to separate the synthetic from the natural fibers, rather than resorting to the use of cotton linters. The sheet sizes are 23" X29" and 30" X40", and the paper is available in pads. Two-ply, nonrag bristol is the most common form of bristol to be found in pads.
One-ply bristol is thin enough to be translucent. The plate finish is thinner than the vellum because of the greater pressure applied in making; thus it is the easier of the two to see through for tracing. Because the one-ply is a bit thin, its hard surface is easily damaged if handled carelessly. It is easily subject to buck ling from the moisture in the air and from the perspiration of your hand.
Two-ply bristol can be used for tracing with the aid of a light table. This thickness is less subject to humidity and damage by handling. Two- and three ply are the most popular thicknesses. Three- through five-ply are chosen more for weight than for any qualitative difference in performance. Five-ply feels like a lightweight illustration board or a 300 lb. hot-press watercolor paper.
Charcoal and Pastel Papers are essentially interchangeable. The selection of the finish and the color of a charcoal or pastel paper is even more important than the selection of the drawing materials since the finish of the paper determines the appearance of the artwork. Pastelists, for example, study the color of a paper the way a painter studies a color chart.
There are two basic finishes-laid and irregular. Laid finish is the imprint of the regular pattern of the wire screen of the papermaker's mould. An irregular finish is the result of the felt mats on which the still-wet sheet of paper is pressed out, which produces a tight, irregular arrangement of small peaks and valleys on the surface. Both of these finishes can be found in different degrees of texture, from cold press to rough. The finishes of this type of paper serve the same purpose as the finishes of watercolor paper; the texture is worked the same way, except with charcoal and pastel instead of watercolor.
These papers are not as durable as Bristol and will take only light erasing before the surface becomes seriously disrupted. They are lighter in weight, generally have little sizing, and are machine-made. "Ingres" usually refers to a laid finish paper of light to medium weight. Strathmore's 100 percent rag charcoal paper comes in twelve colors, two whites, and one black. It is lightweight with a laid finish and is one of the most popular papers of this type. Canson Miteintes, which, it is said, Degas used for some of his pastels, is made in thirty-five colors with an irregular finish and is of medium weight.
Drawing Papers, or papers marketed as "drawing," vary widely in quality from newsprint to the fine handmade Fabriano Roma papers said to have been used by Michelangelo. However, most of the available drawing papers are not even close to this quality. Today, drawing is more popular than ever before and large sheets of rag drawing paper are in great demand. Drawing papers resemble bristol paper, but have not been compressed or as
heavily sized; thus the surface is less durable with a coarse vellum finish and a rougher tooth. Bristol is considered a multimedia paper because it can take everything from markers to watercolor. This is not true of drawing papers permanent markers will bleed and there is little control for traditional watercolor technique. Drawing papers are primarily for use with pencil, crayon, oil pastel, paint sticks, charcoal, graphite sticks, carbon pencil, colored pencil, and some light pen and ink. Common sizes are 18" x 24" and 24" x 36" in sheets, 36" x 10 to 20 yards, and 42" x 10 to 20 yards in rolls. To meet the larger demands, companies such as Andrews Nelson & Whitehead are making available sheets of drawing paper up to 30" x40" and rolls of 60" x 20 yards. White and off-white are most common, but colors can be found. The overwhelming percentage of drawing pads are of the nonrag variety. GtmeralJ.y, if a pad is not labeled as rag, it is not rag.
Bond Papers are sometimes distinguished as ledger bond and layout bond. The finish of bond papers is more like bristol than drawing papers-ledger has more of a plate finish, and layout is a bit like vellum. Layout bonds are usually lightweight, 13 lb. to 20 lb., making these papers translucent, but not transparent like tracing paper. Ledger is usually heavier, 28 lb. to 32 lb., more opaque and less fragile. These papers have good durability and strength.
Both ledger and layout bond work well with a large variety of drawing materials. Watercolors and permanent markers can be used with some success. This type of paper is found almost exclusively in pads or rolls, and most are not rag. The rag bonds are now generally sold as "graphics paper."
VISUALIZING AND DRAFTING PAPERS
This group includes tracing papers, both rag and nonrag, and graphics papers. These papers are designed primarily to be transparent or translucent.
At this time there are no tracing or graphics papers, 100 percent rag or not, that are generally considered archival. The processes used, and the chemicals with which these papers are impregnated, tend to make them impermanent. They should not be used for permanent fine artwork unless they are specifically guar anteed by the manufacturer.
Tracing Paper is, basically, one of two kinds-rag and nonrag. Nonrag, or sulfite, is either inexpensive or expensive, and there seems to be little middle ground. Inexpensive tracing paper comes in pad weights of 11 lb., 13 lb., and 16 lb. and in rolls of 8 lb. and II lb. The lighter weights are sometimes referred to as "flimsy" or "sketch paper." This paper is for rough sketches, preliminary drawings, and overlays, and will work well with most drawing materials. The lesser-quality papers do not take erasure well and will "ghost," leaving a faint impression after repeated erasure. These papers are impregnated with a resin or an oil to make them transparent.
"Vellum" is a term used in drafting and engineering to refer to the expensive or better-quality tracing paper. These papers are made for final drawings where control and detail are most important. The standard for comparison is Canson Vidalson, which is manufactured iµ France. It is a sulfite paper that is made under tremendous pressure so that it becomes transparent. It is the hardest and most transparent, and has the most durable surface of any paper I have seen. Ink can be scraped off the paper with a razor blade without seriously disturbing the surface. This paper takes all drawing media well and is especially good for pen and ink. However, it does have some serious drawbacks-it is easily affected by moisture and skin oils, it tears and cracks easily, and it has poor aging char acteristics. The three most common weights in pads are the #70, #90, and #100, which are most often referred to in terms of pounds. These numbers actually refer to the metric equivalents of 18½ lb., 24 lb., and 29½ lb., respec tively. Sheet and roll weights are most commonly found in #90 and #180 (the equivalent of 48 lb.).
Rag tracing papers are made transparent with oils or resins. They are not as transparent and do not have as durable a surface as the sulfite vellum, but the paper is less affected by moisture and does not tear or crack as easily. Like the nonrag vellum, however, it is easily affected by skin oils and ages poorly. Rag tracing papers, such as Clearprint, are made with a large variety of nonphoto blue graphs imprinted within. A nonphoto blue is a particular color that is not "seen" by most photocopying processes. This permits the use of the graph as a drawing guide without having the graph appear in the reproduction.
Graphics Papers are designed for final work by graphic artists. A number of years ago, 100 percent cotton or rag bond paper pads were labeled "bond paper good for graphic arts and markers." Today, most of the same bond papers are called graphics paper, marker paper, or something similar. There are some that have been especially improved to accept work with permanent markers, or to be particularly translucent, or to be opaque. All make exceptional drawing papers. One of the unique features of this paper is its translucency and its bright white ness, which keeps it from looking like a tracing paper. Although these papers are designed for final work in the graphic arts, do not be confused by the 100 percent cotton or rag label. They cannot, as yet, be considered archival.
SPECIALTY PAPERS
There are hundreds, if not thousands, of specialty papers. Here are a few facts about them. Interleaving, or Separation, Sheets are papers that are pH neutral and non abrasive, and are not necessarily cotton or rag. They are used to isolate artwork on paper from its container, or to protect its surfaces in handling, or to separate pieces of artwork placed in stacks. The three most popular papers for this purpose are Strathmore slip sheets, such soft thin Oriental papers as troya, and glassine paper. Glassine, which recently has come into question for archival storage, is a glossy, transparent, coated paper particularly popular among photographers to protect negatives and photographs, and among painters who need to protect the surface of their paintings. Glassine paper does not leave little fibers stuck to a surface after being in contact with photo emulsions and painted surfaces. One peculiar exception is Cibachrome prints, which scratch very easily. Even glassine paper has been known to scratch this surface. One well known printer of Cibachrome prints finds that only the softness of an Oriental paper like Troya gives real protection.
Transfer Papers, like graphite or carbon papers, are used to transfer a drawing to another surface. Carbon papers are greasy and do not erase well once applied, but they will transfer onto such nonporous surfaces as metals better than graph ite. Graphite is better for transfers to paper or board because it permits transfer of more detail, and it erases more easily. Sarai Transfer Paper, made especially for this purpose, comes in several colors.
Stencil Papers are either waxed or oiled to resist the buckling that otherwise occurs if an untreated stencil is used repeatedly with water-based paints. The popularity of this paper has waned with the development of frisket and drafting polyester (Mylar). Frisket is made from a sheet of either paper or plastic with a low-tack adhesive applied to one side, and comes attached to a paper carrier to protect it until used. Frisket was primarily designed for airbrush stenciling on paper and board. Drafting polyester, which is a polyester with at least one side chemically treated to receive drawing materials, has become popular for making more durable stencils. It is not affected by moisture, it will lie flat even after being rolled up for a long time, and it will not tear.
Calligraphy Paper is any paper that will not easily bleed, feather, scratch, or wrinkle when used with pen and ink. There are a lot of papers treated to look like genuine parchment for use by calligraphers, but calligraphers should not feel limited to paper labeled "calligraphy." Experienced calligraphers often use Strathmore charcoal paper and Canson Mi-teintes. The most popular paper for practice is inexpensive tracing paper.
Coated Papers are used for bookbinding, printing, presentations, mock-ups, architectural models, and other graphic art purposes. There are metallic-coated papers, papers coated with colored inks, adhesive-backed colored papers such as Pantone, silk-screened colors such as Chromarama, and many more. None, how ever, are considered safe for permanent fine artwork.
Cover Paper is another large, nebulous group of papers that come primarily from the printing industry. These papers are of medium weight, 65 to 80 lb., and are used for covers for magazines, booklets, catalogues, and flapping paper. They include a high-grade construction paper. The better grades have good light fastness, are quite durable, and make good drawing and calligraphy paper. Again, these papers are not for permanent artwork.
Decorative Paper is a category that includes printed papers, marbled papers, cockrells, and folk papers such as mingei and rakusui papers. Marbled papers are made by floating oil-based inks on the sized surface of water. The inks are swirled around and then a sheet of paper is placed over them. The inks are picked up and transferred to the paper's surface, resulting in a marbleized pat tern. Cockrells are similar to marbled paper, but the inks are skillfully combed into precise traditional patterns before being transferred to the surface of the paper. This is done with such accuracy that two sheets, each individually made, will look remarkably alike. It can take thirty to forty years of apprenticeship to master the technique necessary to produce matching sheets. To tell the difference between the genuine article and a printed imitation, look at two of the four corners for the partial fingerprints of the maker. They are left when the paper is pulled from the water. Marbled paper and the English cockrells are traditional bookbinding end papers.
Mingei means "folk" in Japanese. Mingei paper is traditionally made from handmade mulberry paper, which is dyed or printed using a hand-cut stencil with patterns hundreds of years old. Some papers are even hand-colored. Yuzen is another paper that is a bit more modem in appearance and in method of man ufacture. These papers are traditional bookbinding and gift papers. Rakusui, which means "rain paper," is made by taking the still-wet paper and placing it over a slightly raised patterned surface, which is then rained with droplets of water. A small number of the fibers are thus washed away, allowing a pattern to develop in the paper. These papers are sometimes referred to as lace papers because their regular transparent patterns resemble lace cloth.
ORIENTAL PAPERS
"A painting, a poem - how paper reveals a man's nature." This old saying reflects the style of Oriental papers. Because their absorbency, texture, and weight instantly show any lack of skill with the brush and hesitation in the mind of the artist, they can reveal the degree of mastery of one's body and mind. Most Westerners find this intimidating and prefer to use Oriental papers only as print paper, since printmaking places distance between the insecure hand and the final result. Perhaps an introduction to the aesthetics of Eastern art would make these materials more emotionally accessible to Western artists.
By Western standards, most Oriental papers are highly absorbent. This allows the artist, as the ink or watercolor is applied, to create shading or a multivalued edge as the brushstroke is made. The character of this edge is determined by the quickness of the stroke and how it is executed, and by the density of the ink in relation to the specific absorbency and texture of the paper. Success is based simply on developing skill, by experiencing how each particular paper will respond.
Oriental papers tend to be made thin for a number of interrelated reasons. Since the artwork is produced with a minimum of ink or watercolor, with little if any rendering, there is no need for thick papers to compensate for the buckling that occurs when using Western water-media techniques. The fibers in Oriental papers also have a natural resistance to swelling when exposed to water; there fore, they do not have to be thick to resist buckling. These papers are made thin for a practical reason, too. Eastern materials and techniques preclude easy cor rection of accidents and errors; thus a substantial amount of paper may be used before success is attained. It is less costly to practice on thinner paper than on thicker paper. After a successful painting is produced, it can be mounted to another heavier paper for handling and display. Even master calligraphers and painters do not get it right the first time every time!
My advice to those who would like widen their horizons by trying such papers as these is to start with a few sheets of the less absorbent papers and work to the most absorbent. When you find a style of paper that you feel you can work with, find the cheapest variety of it, buy a lot of it, and experiment. After you understand the paper's habits and characteristics, you can acquire a better quality. But you should always remember to do a few wann-up stokes on the cheaper version.
The artwork produced on Oriental papers has been traditionally protected first by mounting it on either a heavier paper or a piece of the same paper, and then by mounting it on silk. It was discovered that adhesives break down with time so, to minimize this problem, artwork is mounted with only enough adhesive barely to hold it to the backing. This allows easy removal for remounting at the first sign of deterioration. The purpose of the traditional presentation of artwork in the form of scrolls is to protect the artwork by storing it rolled, thus reducing its exposure to air and light. The artwork is unrolled for special presentations, for a short time, and then rerolled to be stored. In the West, a work of art is usually displayed continually, which is not safe for unprotected scrolls. When creating or collecting Oriental-style artwork, it is important to frame it in a West ern manner if it is to be displayed continuously. (See Framing and Storage)
The tradition of Oriental papermaking is more than eighteen hundred years old. Tragically, there are many traditional papers that will never be made again, because the information about how they were made was not transmitted and has been lost for all time. Nevertheless, there are still almost unimaginable varieties being made today, of which only a select few are available in the West. One of these, for example, called hosho, is made in almost one hundred varieties. I have selected eight distinct groups of papers that are available in the West. They are referred to by their most common names. Many importers and distributors make up their own names for these papers and it is not uncommon for the same paper to have several names. It is usually more practical to shop for these papers with a sample in hand than to ask for a paper by name.
The following papers are listed in descending order of their absorbency. The absorbency of a paper is determined by the arrangement of the fibers and the addition of sizing. Traditionally, the sizing used in Oriental papers is the natural vegetable adhesive mucilage, although the use of Western alum sizing has become prevalent. Many of these papers are available in handmade and machine made varieties, but be aware that being handmade is no assurance of a paper's purity of fiber or neutrality of pH. As a result of diminishing sources of raw materials, more and more of these papers are being contaminated with such fillers as wood pulp, straw, and rice straw, while the price remains high. Some manufacturers have begun to use such traditionally Western sources of raw mate rials as pine trees. They claim to use the same methods of collecting and clean ing the inner bark, or bast fiber, of the tree that are used to collect kozo, mitsumata, and gampi fibers. The core of the tree, which contains the highest lignin content, is not used. They believe that time will prove that these papers will last as long as those made from traditional Eastern sources.
Since few Westerners have any expertise in determining the quality of Oriental art materials, the best guideline of quality, for the time being, is price.
Hosho first appeared around the fourteenth century in the Echizen Province of Japan. The best grades are still made primarily from kozo fibers. Occasionally, mitsumata may be added to improve the paper's elasticity. The lesser grades contain mostly sulfite pulp. This paper is very absorbent. It is thick and fluffy, with a porous surface that is not durable for hard pencil or erasure. Its finishes range from vellum to cold press, and it has a uniform formation with moderate to heavy tooth. A fine quality hosho is one of the most beautiful of white papers. It does not shrink, tear, or expand easily, and it is especially good for woodblock and linoleum printing. Because it is not sized, hosho is also good for soft, semiabstract water colors, but it is not recommended for the beginner. Only an experienced hand is quick enough to prevent the uncontrolled spread of the ink into the paper. The handmade variety has four deckled edges. The most common size is approximately 18" x 24".
Kozo is similar to hosho, but it has a tighter arrangement of fibers, which results in slightly less tooth. It also has smaller pores, which means it has less absorbency. Made from 100 percent kozo fibers, it is the most common variety of paper, as well as the largest category of paper. Kozo can be sized, making it less absorbent and slightly more durable. Its surface ranges from vellum to a coarse form of cold press. The formation of the fibers appears slightly mottled because of the way the long kozo fibers arrange themselves. Kozo is slightly thinner than hosho, and more versatile. The name ''goyu" is sometimes used for the heavier variety of kozo, which is less absorbent and gives a drier, slightly mottled look with watercolors. A common size for kozo is 24" X 36". It is a paper that Westerners can be comfortable with for watercolors and printing.
Moriki could easily be placed in the kozo category because it is also made of kozo fibers, and some medium-quality grades are made of kozo and sulfite. This paper looks and feels very much like a thin kozo paper. It is, however, signifi cantly less absorbent than kozo or hosho, and thus even more versatile for most Western techniques. Moriki has a delicate and translucent appearance, and a slightly shiny surface. It has a finer tooth that is more durable than other kozo papers and will hold some detail with watercolors. The formation is a mixture of evenly arranged fibers and longer mottled fibers, which can be easily distinguished because of the paper's translucency. Full sheets are about 23" x 34".
Mulberry paper is kozo paper. Mulberry is actually the Western name for the plant from which the kozo fibers are derived. Lesser varieties are made from kozo and sulfite pulp. However, there still are enough distinguishing char acteristics to set it apart from the other kozo papers. Mulberry paper is very similar to moriki in appearance, but it is more opaque and somewhat less absor bent. Its surface is durable enough to take light drawing, but with very little erasure. It is the paper of choice for linoleum and woodblock printing. Mulberry is commonly used for stone rubbings, hinges in picture framing, and document repair, and is also the paper which is used to make the decorative mingei papers. Full sheets are about 24" x 36".
Troya is a paper made from kozo fiber, but it does not resemble any of the other kozo papers. This paper has a uniform formation, which, on close inspection, appears to have an open pattern like a fine mesh. Troya has the unusual characteristic of being less absorbent and more porous than other Oriental papers. This means that when watercolor is used, it tends to go right through the paper, but does not spread (if the paint is not allowed to pool underneath). Troya is one of the thinner Oriental papers, and because it is porous, it appears to be very absorbent when in fact it is not. Working with this paper over a blotter will give rewarding results.
In the West, troya is rarely used for artwork, but rather for slip sheets to protect the surfaces of artwork. It is made in two weights; one is like tissue paper, the other like that of moriki. This paper is machine-made and does not have deckled edges. Its size is approximately 24" X36". One of the major importers is no longer distributing this paper, so it has become difficult to find.
Gasen and Gasenshi. Gasen, which originated in China, is the oldest type of Oriental paper still used for artwork. Both the Chinese and Japanese traditionally prefer this paper for calligraphy and for Chinese-style painting. There are other Chinese papers, but since the Revolution, very few have the quality and perma nence necessary for fine artwork. Gasen is one of the few Chinese papers exported to .Japan and North America.
The name "Gasen" is derived from ga, which means "painting," and sen, which is a location in China. The Japanese added the shi, which means "paper," to the name "gasen" to make the translation more fluid, thus "gasenshi" means "painting paper from Sen." Although the Japanese tend to use the names "gasen" and "gasenshi" interchangeably. a paper called gasenshi often indicates that it is a gasen-style paper made in Japan. Gasen was originally made of 30 to 40 percent tampi and rice straw. Today, most gasen is made of either kozo or tampi mixed with straw and bamboo. Although the straw and bamboo considerably reduce the longevity, the traditional working qualities of this paper are con sidered more important than permanency.
This paper is thin, highly sized with a platelike finish, and remarkably strong. The surface is the most durable of all the papers discussed thus far, but it is still not classed as a drawing paper. Many Chinese paintings are done in great detail on this paper. Because it is very thin, it must be used with an absorbent surface underneath it to prevent the paint from pooling and spreading. The pattern of the bamboo mat that is used to pull the fibers from the pulp vat is left clearly imprinted, like a watermark, throughout the paper. This obvious laid pattern is one of the most identifiable characteristics of this paper. The most common size of gasen is 2?1' x 54", and gasenshi is usually found in 18" x 27". Both are with out deckled edges, and are probably no longer handmade.
Torinoko means "child of the bird," or "egg," and its surface resembles an eggshell. It was introduced around the eighth century, and was made of pure gampi. Torinoko made from gampi is probably the most permanent paper made. The Treaty of Versailles was written and signed on this paper because it was believed to be the most permanent paper in the world.
The plant from which the gampi fibers are collected is now rare in Japan, and the plants from other Asian countries are not of the same quality. It is therefore difficult to find a torinoko paper today-even in Japan-that contains gampi, even in combination with mitsumata. With the one exception of a gampi torinoko imported by Andrews Nelson & Whitehead, torinoko is made of kozo, or kozo with mitsumata. The method of manufacture and the addition of sizing have, however, helped to create a paper that looks and behaves like the original. Torinoko is a nonabsorbent Oriental paper, which means it will take water color very much like a Western drawing or watercolor paper. The surface durability of this paper varies, depending on its method of manufacture and on what substitute for gampi was used. It is a thick, heavy, strong paper, with two workable sides-one a fine vellum and the other a nappy, cold-press finish. Machine-made torinoko comes 18" x 24" without a deckle; handmade torinoko is roughly 24" x 36" with a deckle.
Masa paper is the least absorbent of all the papers and the easiest for a Western watercolorist to work with. In overall appearance it greatly resembles torinoko, but today it is made primarily of sulfite pulp, and when it is soaked with water it tends to fall apart. Although this paper is not strong, it does allow the control that Western painters prefer, and it does have one additional advantage over the other Oriental papers-it is available in rolls of 42" X 10 yards, as well as in sheets of roughly 18" x 24". Masa is machine-made and has no deckle.