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Papyrus

See BPG Papyrus

A writing support used primarily by the ancient Egyptians made of lengthwise strips cut from the soft, white inner pith of the Cyperus Papyrus L reed native to marshy areas of North Africa. Papyrus was used in the Mediterranean region from perhaps the fourth millennium B.C. to the twelfth century A.D. The fabrication technique was lost in the Middle Ages. Strips were probably soaked in water, rolled to soften, laid down to form an overlapping cross-laminated structure, then pressed to bond and dry. There are different theories about what bonds the strips together -added adhesive, natural sap, or physical adhesion. Formed sheets were pasted together to form long rolls. Ancient examples may be firm, smooth, flexible, and translucent and of a fine and even texture; modern products are often heavier and thicker.

Inherent Problems

• Uncertainty about the manufacturing process presents problems: if starch paste was used in bonding then aqueous treatments could endanger the adhesion of the two layers forming the sheet.

• Analysis has shown that proportions of the main constituents of papyrus (cellulose and lignin) vary with age, manufacturing process, and environmental effects. If well-made, properly housed, and cared for, papyrus can be a durable material which may be repeatedly rolled and unrolled over time. Eventually its flexibility diminishes; ancient papyrus may now be desiccated and brittle as well as discolored. It also has a strong tendency to curl up unless restrained. Edges fray easily. Nineteenth and twentieth century methods of handling, storage, and display often consisted of taping or gluing the papyrus to cloth, poor-quality cardboard, cellulose nitrate, hardened gelatin sheets, or clamping between sheets of glass in passe-partout. Acids have migrated from these materials into the papyrus. In addition, papyri within such mounts have fractured because of tensions between object and support in fluctuating atmospheric conditions (Elliott 1987, 64).

Treatment Observations

• Alignment of fragments: Pronounced fibers of cross-laminate structure, obvious on a light table, may assist in positioning improperly placed fragments. Deteriorated papyrus may be so brittle that it is impossible to handle without dampening; however, its surface becomes tacky when wet. Nylon gossamer tissue is used as a work surface at the British Museum. Overall moistening is recommended to prevent formation of stains that occurs with local wetting; a solution of 1:1 industrial methylated spirits (IMS), (or ethanol or acetone), and water permits alignment of fibers, manipulation of distortions, removal of creases, etc.

• Backing removal: Removal of fragile, brittle papyrus from poor quality secondary support is assisted by using a facing. Some poultices (cellulose ether, sodium carboxy methyl cellulose [SCMC]), damp blotter method or both have been used to remove backings, inlays, and old repairs. Scrape away residues in the direction of the papyrus fibers to avoid damage.

• Aqueous treatments: Discolored and stained papyrus apparently responds well with no layer separation problems. In order to remove discoloration and acidity by washing, the sheets must be reasonably sound. Float washing on Mylar or between two sheets of nylon gossamer web is recommended; papyrus' natural buoyancy contraindicates immersion.

• Repair: Papyrus has a strong tendency to return to the position it has been held in over a long period of time (e.g., rolled). At the British Museum, gluten-free wheat starch and Japanese paper were used to repair papyrus successfully on the light table.

Some papyrologists feel that repairs on literary texts and archival documents should be visible so that the origin of the texts' arrangement is clear. This will aid interpretation of the text. Before treatment photography is, of course, also helpful.(KDB)

• Removal of acidity: pH of papyrus is acidic because of its relatively high lignin content (unless formerly buried in alkaline conditions).

• At the Princeton Library, a papyrus mask from a mummy (dating from Ptolemaic times) was disassembled in order to ascertain presence of informative texts or documents. A Danish freeze/dry technique was used in which the object was soaked in an enzyme (to dissolve the adhesive) and then freeze-dried to remove the water and adhesive. In addition, some parts required steaming in order to release them.(KDB)

Palm Leaf

A most ancient support for writing and miniature painting, according to Pliny, palm leaf can be archaeologically documented back to the second century A.D.. Palm leaf manuscripts preserve many unique sources of Indian, Nepalese, and Southeast Asian culture and religion. They continue to be used in the twentieth century. Preferred leaves are those from the Talipot and Palmyra palms which are plicate (i.e., having parallel folds) and segmented with a central rib. The hard, yet flexible flaps on either side of the rib yield the material that is prepared by drying and polishing for writing or painting or for incising characters using a metal stylus. Up to 400 leaves were, traditionally, laced together through pierced holes to form a “book.”

Inherent Problems

• Palm leaf is very susceptible to desiccation by a hot, dry environment; it will lose flexibility and become brittle. The lignified cells are particularly susceptible to degradation and discoloration.

• When exposed to high RH conditions or actual wetting the leaves may stick together in solid blocks.

• Palm leaf has poor resistance to wear and tear; it is easily damaged by constant handling, especially at the edges which can fray.

• The leaf tends to split into long strips along the longitudinal veins, especially where incised previously with a stylus. Once begun, mechanical damage progresses through the leaf.

• Damage is caused by friction between the cord and the edge of the hole.

Treatment Observations

• Correct storage in a controlled environment is the best way to prevent damage to palm leaf manuscripts and should be designed to minimize the need for unnecessary handling. (See Lawson 1983 for current practices at the British Library.) To lessen effects of damage from lacing, the British Library strings the leaves into books using the left hole only.

• Palm leaf manuscripts with very small holes, there by tradition rather than for practical use, should not be strung.
  

Parchment/Vellum

Known since ancient times and used as a support for writing, painting, drawing and printing, it is made from the skins of animals, especially goats, calves and sheep. The varieties differ in grain pattern, markings, fat content, thickness, color, and flexibility. Parchment is prepared from pelts (i.e., wet, unhaired and limed skins) simply by drying at ordinary temperatures under tension, most commonly on a wooden frame known as a stretching frame (Reed 1972, 119). The result is a stiff, flat, generally opaque sheet. The pelts are not irreversibly tanned with acids, the method used to make leather. Parchment is quite permanent and durable; capable of lasting thousands of years if kept in stable environmental conditions.

The terms vellum and parchment refer to skins which are prepared with lime in exactly the same way. They have had different specific meanings depending upon when and where they were made. The modern British definition of parchment refers to skins made from sheep; vellum to skins made from calf, goat or other animals. Vellum, in the past, has implied the fine, white skins used for the exquisite Books of Hours, but in modern times it is often used to imply bookbinding weight skins, leaving parchment to refer to the document weight skins. Yet, fine skins are still made from calf, and stiff, thick skins are made from sheep. Thus, the issue of precise terminology is somewhat confusing. Since it is so difficult to distinguish the animal used to make an early manuscript substrate, a prominent paleographer uses the term parchment for all animals when describing manuscript skins.

Hair and flesh sides are terms often used to describe parchment. The hair side (i.e., the outer or grain side of a skin) will often be gelatinous in look and smooth with a grain pattern or hair follicles occasionally visible. This is from the treatment of the skin and the shaving action of the knife. The flesh, or inner side, is usually much softer, more absorbent, with a loose, velvety appearance. When the hair side has been pumiced (pounced) in preparation for the ink, it is made velvety and thus it is difficult to distinguish hair from flesh sides. If the flesh side has been shaved with a knife and prepared to have a smooth finish, it is also difficult to tell hair and flesh sides apart. The flesh side is generally more receptive to humidity, so the skin will curl in the direction of the hair side.

Fabrication: One should become familiar with the preparation of parchment as a basis for understanding its working properties, sensitivities, and limitations. The basic methods used today are similar to those used in the Middle Ages, but the medieval techniques attained a perfection which has been progressively neglected since the sixteenth century. Parchment is made from dehaired, limed pelts which are dried at ordinary temperatures under tension and shaved with a semi-circular or lunar knife to desired finish. The wet, limed pelt is stretched on a frame to dry under tension which plays a critical part in the structure of parchment. The fiber network in any pelt is complex, with the fibers running in all directions, giving flexibility to leather. During the simultaneous stretching and drying process to make parchment, however, this fiber orientation is changed to be realigned into layers parallel to the flesh and grain surfaces of the pelt. This reorganization of fibers is set in this new and highly stretched form by drying the pelt fluid or ground substance (a mucous-type secretion) to a hard, glue-like condition. It is this realignment of fibers which produces a taut, stressed sheet which is relatively inelastic and has a stiff handle. It is also the distinguishing factor between parchment and leather, not merely the fact that leathers are tanned. Ancient pelts were sometimes processed into parchment and then also tanned (see Reed 1972 for more detail). In the West, the surface was sometimes prepared with chalk or similar material to increase opacity and absorbency. Some skins were also given a nappy surface for use with pastels, especially in the eighteenth century.(LP)

Inherent Problems

Parchment is a relatively stable material in that it is resistant to deterioration. It absorbs few sulfurous acidic pollutants and those it does tend to be absorbed by its natural alkalinity.

• Parchment is very hygroscopic; a humid environment makes it swell, a dry atmosphere dehydrates it so that it shrinks and becomes stiff. It is the ground substance which is extremely reactive to humidity and can absorb water even after dried in the parchment. If parchment absorbs large amounts of water, the fiber network can relax since it is not constrained. When the fiber network system is dried in this new relaxed state, the parchment can become hard, horny, and cockled. Therefore, exercise extreme caution when storing or treating parchment. To retain the properties of parchment, any treatment involving humidity should also involve drying under tension to maintain the stressed, parallel alignment of fibers.

• Dimensional changes in the parchment support caused by relative humidity fluctuations can create tensions in the parchment which can cause detachment of media.

• High humidity levels will lead to microbial attack on parchment and consequent weakening and staining. It also enhances the usual chemical degradation reactions (e.g., excessively acid inks can transform the support into lacework) (Chahine 1989, 15).

• Can be easily torn or cracked if the skin has suffered from deterioration, is thin, and/or the conditions are too dry with excessive stress.

• Greek medieval (Byzantine) artists coated the finished parchment sheet with an egg-white preparation and polished it; this created a smooth, shiny surface from which media readily flakes (Abt and Fusco 1989, 61).

• Often the same color as paper, very thin and flexible, though with a “solid” feel and a tough “body,” parchment can easily be mistaken for a sturdy paper. Parchment's behavior and recommended care, however, are radically different from that of paper, because of the great differences in basic natural materials from which each is made. When parchment is mistaken for paper and subjected to certain paper conservation procedures, the results are disastrous (Ellis 1987). Parchment cannot be immersed in water, for instance, because the lime can be removed, and the skin can wrinkle and go transparent. Exposure to heat is disastrous as the skin can irreversibly shrink.

• Since parchment is so hygroscopic, one can expect it to expand and contract with seasonal changes in RH and temperature. A certain amount of cockling in an item considered for treatment is not only inevitable but also aesthetically inherent. Concern must be given to cockles affecting media attachment. Traditional methods of hinging using paste and Japanese tissue can result in cockling around the hinge as the skin expands and contracts, while the pasted hinge area moves at a different rate. Hinging methods have included string matting (see Clarkson 1987, 201–209), suspending with Mylar tabs and applying the feathered fiber ends of Japanese paper strips all around the perimeter.

Treatment Observations

The methods used to treat parchment are based on those used to originally prepare it.

• Surface cleaning: Use brushes, soft erasers, low suction vacuum, swabs, and a minimum amount of moisture. One must be very careful that eraser particles do not become trapped in the fibrous surface of the parchment, especially in areas where the surface is creased or abraded.

• "Performing miracles on water-staining and grime can't really be expected since the skin cannot be immersed in water" (Munn 1989, 30). Use the least moisture possible to remove water-soluble adhesive residues. Try ethanol and water mixtures and work locally under the microscope. Use of the suction table may be effective for local stain removal as well as flattening.

• Appearance of transparency in the course of conservation treatments, especially as a result of the application of water, water/alcohol, and urea solutions, lanolin, glycerol, excessive tension, etc. (Chahine 1989, 17–18).

• Methods of repair should "aim to preserve the original character of the material by using methods related to the parchment-making process, in particular...hydration and tensioning" (Cains 1982/83, 15).

Water-damaged or distorted parchment may respond to humidification in a constant humidity chamber, on a damp pack of blotters through several layers of permeable polyester web or Gore-Tex, or overall applications of alcohol or alcohol/water solutions. "The advantage of the chamber method is that the hydration process is slow and one can determine the best conditioning point within a broad time scale"; timing with the pack system, particularly if the parchment is thin or there is a danger of offsetting, can be critical (Cains 1982/83, 16; Munn 1989, 31). With the pack there is a risk of transparency and/or excess water absorption.

Extra humidity may be applied to more severely affected, horny, or less absorbent local areas during overall humidification; use moist, not wet, blotter pieces over permeable polyester web on distorted areas or apply water/alcohol solutions locally. Water alone can darken parchment.

The appearance, opacity and surface texture of parchment can be altered during hydration and tensioning (Cains 1982/83, 15–16).

• Flattening/Tensioning: Pressure methods of flattening do not preserve the original character of parchment nearly as well as tensioning which reflects the original parchment-making process (Cains 1982/83, 15). Tensioning "must restrain the skin while it is drying until the moment of reaching equilibrium when the skin comes under tension and is more or less flat." The relaxed condition of the humidified skin may lead to overstretching; with very distorted parchment, tensioning may be undertaken gradually in a series of steps (Cains 1982/83, 15–17). If dried too fast after humidification distortion may result.

Poorly modified clips combined with high moisture content in the skin will produce indelible marks around its edges.

• Applications of lubricants to shrunken material that does not respond to hydration and flattening (see Chahine 1989, 17–18).

• When mending skin use only structurally similar materials (e.g., gelatin or parchment size for the adhesive, parchment and goldbeater's skin or fish skin membrane for the mending materials). This should prevent stresses resulting from different expansion/contraction rates which may cockle and tear the parchment.

• Because of its extreme hygroscopicity it is essential to keep parchment in a stable environment: 18°C ±2° (64.4°F ±2°), 55% RH ±5% (Chahine 1989, 15). The benefits of flattening parchment can be largely negated by dry storage or exhibition. Maintain a micro-climate within exhibition cases that will conserve the equilibrium moisture content of the parchment, see, for example, Cains 1982/83, 21.

• Media consolidation is frequently necessary. Use parchment size in various dilutions with water and ethanol or isopropanol. Apply locally with brush or spray when there is overall media friability. Press after spraying if possible.(LP)

Pith/Rice "Paper"

Soft, velvety, translucent, ivory colored, spongy, paper-like substance not made from rice and not true paper; pith of the Asiatic shrub, Chinese cottonwood (Tetrapanax papyrifera Hook Koch), native to hills of South China and Taiwan. A popular support for Chinese export watercolors from the 1820s on.

Technique of manufacture is described by Bell (1985, 109–117). For preservation purposes it is important to know that the “paper” is formed by cutting a rod of pith into a spiraling ribbon; these lengths are then pressed flat and trimmed into sheets. The sheet's grain direction is visually obvious. Aged pith ranges in color from stark white to cream to pale gray.(CS) Under the microscope pith “paper” appears to have a cellular, non-fibrous structure. Pith, the tissue in the center of the plant stem, is made up of large food storing and conducting cells (parenchyma and collenchyma) which are very responsive to moisture. This accounts for pith “paper's” receptivity to watercolor which is readily absorbed by its surface causing swelling and a permanent relief effect.

Inherent Problems

• Pith "paper" is so fragile that pressure from a finger can create a permanent depression (seen frequently on these objects) and a finger nail easily slices it. Use a secondary support whenever possible to avoid direct contact. The porosity leads to easy discoloration by embedded dust, severe staining – even from materials applied to the back (e.g., original mounting adhesives). The appearance of the pith is such that tissue fills are very obvious. If scraps of pith are available for filling, be sure to match grain directions. Scraps of a different tone can be lightly brushed with dry pigment mixtures to improve color compatibility. Splits have often drawn apart, with resultant gaps.(CS)

• Pith "paper" is quite flexible in humid air and can be stretched and molded when damp. Water and some organic solvents may make it temporarily transparent. Wetting or washing by immersion will expand the support permanently. It becomes more brittle with drying and even when new it has poor fold resistance. It may curl or crack with exposure to excessive heat. The fragile surface is easily damaged by abrasion and by uneven or excessive pressure. Pith "paper" becomes brittle with age, it cracks and tears easily when improperly handled or stored.

• Presentation: Traditional presentation was by ribbon binding around all edges (most likely to protect against splitting) and then assembly of individual sheets into a bound volume (Purdue and Kraebel 1961, 177). In its original form, it is likely to be found mounted on album pages of good quality paper (Chinese/European). Poor-quality European secondary supports are likely to be of later origin. Often paintings are only tipped on or otherwise locally attached. Rapid expansion and contraction of sheets with humidity changes can lead to physical damage if they are restricted by glued areas and mounting methods.

Treatment Observations

(See also Rickmann 1988.)

• The pith sheet's surface is very delicate and porous. Avoid removing surface deposits by brushing, this may embed mold or dirt. Do not use a scalpel to pop off accretions, this will only cause more problems.(CS)

• It is very difficult to mend tears because of both translucency of the material and difficulty in manipulating it. F. Mowery's gossamer tissue (or as a second choice tengujo) impregnated with Klucel G and applied by rolling a dryish swab of ethanol over the tissue works well. To set: immediately place Teflon cloth over the swabbed tissue, press lightly with fingers and blow away the ethanol.(CS)

• Pith sometimes shows foxing or glue staining. Stains can be successfully treated locally with water and blotting paper. Use of the vacuum suction table may not be safe because pith is so spongy, but with some sheets it can be used at very low suction.(CS) To a certain extent, strength and flexibility of pith “paper” is enhanced with wetting so aqueous methods of repair would seem to be the methods of choice. Yet, most conservators use only a minimum amount of moisture. This is because the pith paper tends to absorb water like a sponge; on these vividly painted objects at least one pigment always seems to be extremely prone to wicking upon exposure to water (as opposed to moisture vapor).(CS) Some conservators use methyl cellulose as adhesive to control water content during lining and mending.

• Pith paper should not be lined unless it is very fragmented since puckering (and slight relief effect) of the support caused by the pigment layers is original. Since tears/splits have no overlap, and thus are difficult to repair successfully, lining is sometimes necessary. To avoid pressure on surface when a pith “paper” support must be lined and flattened, and to eliminate severe curl and tenting at cracks after lining, a modified “polyester lining” technique may be used. Sanded Mylar is taped to solid, flat surface. Woven polyester fabric is laid on Mylar, impregnated with very thin paste and stretched out evenly. Japanese paper is brushed out on fabric and allowed to dry. Lining paper is coated with thin layer of relatively viscous methyl cellulose, humidified pith “paper” is set on lining, gently aligned and allowed to dry. Then Mylar and polyester are each peeled off back without need to strain and crack pith “paper.” More traditional methods using Japanese papers and wheat starch paste can also be successful. Make lining and presentation system sufficiently larger around edges to minimize exposure to handling.(CS) Minimum pressure must be used at all times or the pith surface becomes “dead” or flat. On the other hand, previous mounting or storage may leave the sheet quite compacted before it arrives for treatment. In such cases, controlling other factors may become more important.(CS)

• When missing areas must be replaced only butt joins are suitable; match the grain directions. Apparently, pith paintings can still be bought in Hong Kong, which could be an option for obtaining repair material.

• Display: Pictures that have been cut from their albums in the past should be individually displayed. It is possible to “cradle” each sheet so that there is no application of paste to the pith, nor any restriction of movement by hinges. Cut strips of a suitable material and paste along outer edges to mat backing board so that inner edges of strips overlap pith sheet and hold it securely in place. An eight-ply overlay window mat will ensure adequate protection for the fragile pith surface. This method is not suitable for album display.
  

Tapa

A paper-like fabric or bark cloth made from the inner bark of the paper mulberry (Broussonetia papyrifera) and other plants. Produced and used extensively in the Pacific region as a painting and writing surface, for clothing, wall coverings, etc., since earliest times. Processing includes cutting, soaking, and softening the stalks in water and stripping off the bark. (Tapa differs from paper because the fibers retain their original structure and are not disintegrated.) The inner bark is sun-dried and stored; for processing into tapa it is soaked in water to soften and then repeatedly beaten and folded until it has increased to many times its original width. Large tapas are made by pasting, felting, or sewing pieces together. The many ways of decorating tapa are described in the literature. Tapa continues to be manufactured widely.

Inherent Problems

• Light-sensitive colorants: In particular, modern tapas may feature inks from felt-tipped pens.

• Water-sensitive colorants, especially "smoked" tapa; water-sensitive adhesive joins between the individual tapa pieces forming the composite object. Joins may separate when wet.

• Glossy surface coating of coconut oil is susceptible to mold (Green 1987, 59).

• Storage and display problems for very large pieces. Traditional folding for storage causes deformation and breaking of fibers.

• Delamination of layers (with age, washing) and usual problems (cracks, holes, tears).

• Frequently acidic and brittle.

• Soiling from wear and greasy, sooty dirt accumulated from cooking fires can be a clue of dating (Green 1986, 20).

• Some may retain rolled or distorted shape of the tree.

Treatment Observations

• See Green (1986, 20) for factors to consider; in surface cleaning and washing must not remove ethnographic evidence (soils) for history and use.

• Cleaning: Vacuuming is acceptable for removal of dust. Take care with paints as they can be friable depending upon binder.

• Crease removal: Wetting, steaming, and humidification have all been tried with limited success. Tapa must be handled with great care and adequate support when wet because its strength may decrease.

• Tear repair: Mulberry paper is satisfactory for tears and small voids.

• Backing/Lining is a treatment of last resort for tapas which are structurally insecure and which would not be adequately supported with patch-type repairs. Linings may obscure previous repairs which may be historically significant. Embossing, if present, should remain visible. In addition, embossing may make it difficult to adhere the backing. Linings also contribute to a loss of flexibility. Lining materials include Japanese paper and contemporary tapa (the latter is preferred, in part because it conforms more readily to the surface irregularities of the tapa primary support). Starch paste or cellulose-derived adhesives are preferred, particulary the latter because in any future analysis it will not be confused with the original adhesive. Nylon laminating tissue and stitching have also been used to adhere linings.

• Filling voids: See tear repair, above, for treatment of small voids. Larger voids need backing or pulp fills. The latter is the standard treatment and uses coarsely processed pulp.

• Mounting methods include hinge mounting, pressure-mounting, clips, etc.
  

Drafting Cloth ("linen")

While "linen" as a primary support was required for all United States government contract work in the 1950s, it was widely used as a support for architectural and engineering drawings from circa 1850 to 1960 when it was replaced by cheaper, durable polyester films. Drafting cloth was manufactured in Lancashire, England and exported all over the world. The substrate was a linen or cotton fabric and could be bleached, then filled or coated with starch, gelatin or, more recently, synthetic compounds. Sometimes the completed drawing on drafting cloth was coated with lacquer-like coatings, including nitrocellulose, which resulted in a very brittle support.(KN) A glossy coating on one or both sides created a smooth surface that is translucent rather than fully transparent. Drafting cloth is seldom used today because of its high cost and limited availability. Also, it was formerly required for deposit with building inspection departments as a permanent copy, but is no longer (Lathrop 1980, 329).

Inherent Problems

• The textile substrate is very durable and will withstand much abuse. However, a starch or gelatin filler/coating can be destroyed by moisture resulting in distortion, opacity, exposed fibers, and limpness.

• The starch or gelatin coating renders drafting cloth susceptible to damage from mold, insects, vermin and foxing.

• Heavily filled/coated: Ink and watercolor will not penetrate drafting cloth and, therefore, their application is not permanent. May be washed off with moisture or smeared if handled poorly.

• Storage and handling: Rolling, folding, and poor handling techniques crack the coating and will cause it to wear off gradually. Eventually, the cloth will fray around its outer edges.

Treatment Observations

• Mold removal may be successfully accomplished using a vacuum aspirator.

• Dry cleaning to remove superficial grime is safe only when the surface is in excellent condition (a smooth, unfractured coating). Eraser particles can become embedded in exposed fibers or “rub out” the fragile coating. Swabbing with ethanol often releases surface grime.(LP)

• Selected organic solvents have been used with success to reduce staining, adhesive residues, etc. Some linens benefit from cleaning with water and ethanol mixtures.(LP)

• Mend with heat-set tissue or aqueous adhesives, however, drafting cloth may be heat-sensitive, especially when degraded. Aqueous adhesives will disturb the starch or gelatin filler/coating. Coating can be approximated by applying methyl cellulose and burnishing through polyester film.(LP)

Contemporary Non-Paper Drawing Supports

Stiff but flexible, colorless plastic sheet with a fine, pebbly surface coating that makes it almost opaque and which readily accepts media. One type, Geofilm (made by Hughes-Owens, Ltd., analyzed at the Canadian Conservation Institute in 1987), was found to have a dimensionally and chemically stable polyester base (unaffected by heat, humidity, solvents) and a coating of quartz (also stable) in a solvent-resistant ester binder (Williams 1987). The binder will probably remain stable if the film is stored in conditions recommended for photographs on a polyester base. Any color change that occurred over the years in such a thin layer of binder would probably be imperceptible. A variety of other synthetic drafting films is available, however, many of which are not as stable as Geofilm. Most have not been chemically analyzed, but spot tests show that some have surface coatings that dissolve readily in many solvents. One such film is Transpagra. The bases of these drafting films may be any of a number of plastics of varying stabilities.

Mylar has also been used as a support for drawings as well as architectural renderings. Jasper Johns drew on Mylar and Andy Warhol has done drawings which contain layers of transparent plastic. Drawings for design items and other industrial products have been done on single sheets and composite pieces of Mylar. (KDB)

Inherent Problems

• It is difficult to start a tear in polyester drafting films but, once started, the tear extends easily.

Treatment Observations

• Conventional mending and hinging adhesives for paper are incompatible with drafting films. Synthetic adhesives, whether solvent or heat activated, must be tested for compatibility with each film, since some films are heat or solvent sensitive.

• Synthetic hinging materials (Hollytex, Cerex, etc.) have been used with success. These materials, once impregnated with a synthetic adhesive (Lascaux 498–20x, etc.) can be heat or solvent activated. The translucent appearance of the hinges renders them almost invisible. (AM) Double-sided tape has also been used for hinging plastics. (KDB)

• Large and oversized pieces may have been folded. Humidification is not generally effective. Flattening may be achieved by light application of heat and pressure (conventional tacking iron and silicon release paper) on crest of crease. (SP)

• Reformatting (e.g., microfilming) should be considered for architectural drawings on unstable plastic although this option is not applicable to fine arts pieces. (LP)

References

(See also General References)

Traditional Non-Paper Supports

Bell, Lilian. Papyrus, Tape, Amatl, and Rice Paper; Paperrmaking in Africa, the Pacific, Latin America and Southeast Asia. 2nd edition. McMinnville, Oregon: Liliacea Press, 1985.

Lenz, Hans. El Papel Indigena Mexicano, Historia y Supervivencia. English translation by H. Murray Cambell 1961. Mexico D.F.: Rafael Loeray Chaven, Editorial cultura, 1948. (amate)

Shagun, Fray Bernardino de. Florentine Codex, General History of the Things of New Spain. Translated by Charles Dibble and Arthur, J.O. Anderson, in thirteen parts. Santa Fe: School of American Research and the Museum of Mexico, 1963. (amate)

Papyrus

See BPG Papyrus Bibliography

Palm Leaf

Lawson, Peter. "Conservation of Palm Leaf Books." Conservation News 36, 1983, pp. 14-19.

Van Dyke, Y. 2009. “Sacred Leaves: The Conservation and Exhibition of Early Buddhist Manuscripts on Palm Leaves”. The Book and Paper Annual, Vol. 28, pp. 83-97.

• The article describes the material composition and preparation of a collection of Indian paintings on palm leaf and paper, from the Metropolitan Museum of Art. The author describes in detail the different types of palm leaves and their physical properties as well as the methods used to process the leaves to make them suitable to paint on. These methods include: smoking, soaking, being boiled in water, hung over a charcoal fire and dried by the sun or kiln.
• The pigments were identified, though the method of identification was not mentioned, and due to the brittle nature of the palm leaf these pigments had to be consolidated. The choice of consolidant was made based on the desired working properties, which included strength, ageing, flexibility, viscosity, aesthetic and penetration. Gelatines and methyl cellulose were tested on the manuscript but they were not strong enough, left tidelines and dried glossy. Isinglass was chosen and used as a warm solution at 1%, this adhesive proved to be the best consolidant for both the flaking paint and the actual palm leaf. The leaves were humidified to rehydrate them and reduce the planar distortion, once humidified the leaves were less brittle so they could be more easily repaired using acrylic-dyed Japanese tengujo papers. The article also described the ethical consideration made when treating these objects, the storage solutions adopted to safely house the manuscript, and the exhibition conditions including mounting and display.
• The paper is a very detailed and comprehensive conservation case study, which included the historical context of the object, material analysis, ethical considerations and future storage recommendations. Though the paper was aimed at professionals in conservation, the article appeals to a wider audience, providing useful information to researchers, historians and curators; this added importance to the content as it promoted interdisciplinary collaboration and awareness.

Parchment

Abt, Jeffrey and Margaret Fusco. "A Byzantine Scholar's Letter on the Preparation of Manuscript Vellum." Journal of the American Institute for Conservation 28, No. 2., 1989, pp. 61-66.

Cains, Anthony. "Repair Treatments for Vellum Manuscripts." The Paper Conservator 7, 1982/83, pp. 15-23.

Chahine, Claire. "Le Parchemin." Proceedings of the International Symposium: Conservation in Archives, Ottawa, May 10-12, 1988 International Council on Archives, 1989, pp. 11-24.

Clarkson, Christopher. "Preservation and Display of Single Parchment Leaves and Fragments." Conservation of Library and Archive Materials and The Graphic Arts. Guy Petherbridge, ed. London: Butterworths, 1987.

Forstmeyer, K., 2012. "Parchment Leafcasting Revisited", Journal of the Institute of Conservation, 35:2, pp.219-229.

• The repair of a difficult area of loss on a piece of parchment can achieved by using a vacuum table and making a suspension of animal collagen fibres to create ‘reconstituted parchment’. The technique of wet-casting pulp dispersions on an object is discussed, as well as the application of reconstituted parchment with different adhesives, and methods of dyeing the fill to achieve the most appropriate colour.

Munn, Jesse. "Treatment Techniques for the Vellum Covered Furniture of Carlo Bugatti" The Book and Paper Group Annual 8, Washington, DC: AIC, 1989, pp. 27-38.

Reed, R. Ancient Skins, Parchments and Leathers. London: Seminar Press, 1972.

Pith Paper

Lee, Mary Wood. "Conservation Treatment of Structural Damage to Pith Paintings." Paper presented at the AIC 18th Annual Meeting, Richmond, Virginia, May 29-June 3, 1990.

Perdue, Robert E., Jr. and Charles. J. Kraebel. "The Rice-Paper Plant - Tetrapanax Papyriferum (Hook) Koch." Economic Botany 15, No. 2, April-June, 1961, 165-179.

Rickman, Catherine. "Conservation of Chinese Export Works of Art on Paper: Watercolors and Wallpaper." The Conservation of Far Eastern Art: Preprints of Contributions to the Kyoto Congress. London: IIC 1988, pp. 44-51.

Tapa

Green, Sara Wolf. "Conservation of Tapa Cloth: Filling Voids." The Paper Conservator 11, 1987, pp. 58-62.

Green, Sara Wolf. "Conservation of Tapa Cloth from the Pacific." Preprints of Papers Presented at the 14th Annual Meeting of the AIC. Chicago, IL: 1986, pp. 17-31, with earlier bibliography.

Drafting Cloth

Douglas, Robyn. Architectural Drawings on Drafting Cloth. Unpublished report, Kingston: Queen's University Art Conservation Program, 1989.

Lathrop, Alan. "The Provenance and Preservation of Architectural Records. The American Archivist 43, No. 3, Summer 1980, pp. 325-380.

Contemporary Non-Paper Drawing Supports

Hodges, E., ed. The Guild Handbook of Scientific Illustration. New York: Van Nostrand Reinhold, 1988.

Williams, R. Scott. CCT Analytical Report, ARS Analytical Report No. 2631, Geofilm, CCI Registry File No. 7034 18-11, Ottawa, Canada: CCI, Sept. 25, 1987.

History of this Page

This page was created in April 2025 by Sandrine Blais from the BPG Paper Supports and BPG Support Problems pages.