The Abbey Newsletter

Volume 12, Number 8
Dec 1988


Symposium 88 Oct. 3-7, Ottawa

by Ellen McCrady

Everyone said this was a well-paced, first-rate symposium. The 300 or so people who came were treated to five full (but not over-full) days of papers, demonstrations and tours on conservation of books, archival paper and art on paper. Abstracts were given out with the program, and the proceedings will be published. About 38 papers were given, of which only a few will be described here, with the help of my notes, speakers' handouts, and the book of abstracts. As usual, I beg the reader's indulgence for the errors that seem to be inevitable in this type of report, and invite corrections.

Symposium 88 was organized by the Canadian Conservation Institute (CCI), the National Archives of Canada and the National Gallery of Canada. Papers were given in the auditorium of the spectacular new building of the National Gallery, which is on a promontory overlooking the river, but still within walking distance of downtown Ottawa. Tours of the conservation facilities of all three institutions were part of the program, though the National Gallery's facilities are not finished yet.

Season Tse and Helen Burgess of the CCI had a paper on degradation of paper by enzymes, a product of the CCI's long-term enzyme study. They found that 21 of the 29 enzymes tested did degrade the seven types of paper they tested, lowering the degree of polymerization (DP) by as much as 36%. (Enzymes are often used to digest old adhesives that have become insoluble with age; degree of polymerization, as measured by viscosity, indicates soundness or degradation more directly than the folding endurance test.) On the basis of this work, they concluded that amylases were less harmful, and that if a protease was needed, trypsin should be chosen.

Cathy Craig-Bullen surveyed the price and performance of leafcasters on the market: the Recurator, the A.B.A. machine, Vinyector, Union Instrument sheetformer, Per Laursen s models including the continuous leafcaster, the Folger Library's custom model and others. She had a handout with ordering information for six of them. Peter Mecklenburg will market one based on the Folger model within the next few months for about $4,000. For small labs, she said, the small Danish or Mecklenburg models are probably the best.

Vincent Daniels couldn't come, but his paper on foxing, co-authored with Nigel Meeks, was delivered by J. Cliff MacCauley. Although both metals and fungi may cause foxing, this paper concerned only "Foxing Caused by Copper Alloy Inclusions in Paper." The copper is assumed to come from beaters in the paper mill. Particles over 10 microns were detected by x-radiography; some were foxed, some not. They were examined by scanning electron micrography (SEM), and were seen to take the form of a nucleus, often with a halo that showed up by ultraviolet (UV) light. The nucleus was composed of dendrites (branching crystalline mineral growths) that followed the fibers. Elements in the nucleus but not in the surrounding paper were identified by EDX and digital x-ray analysis mapping: copper, sulphur, chlorine and zinc. Even elements in individual fibers and crystals were identified. One photomicrograph showed a green fiber with sulphur and copper crystals sprouting out of it, in the middle of a black area. The elements were distributed differently: chlorine stays in the nucleus, zinc is found in the halo. The copper and zinc were hypothesized to have been there originally, and to have combined with chlorine in bleaching, forming soluble compounds that migrated. Three types of nuclei were distinguished: cauliflower, brown flat and brown discolored.

Chandru Shahani also gave a paper dealing with copper, co-authored with Frank Hengemihle: "The Effect of Deacidification on the Aging of Paper Contaminated With Copper." At the Library of Congress's Preservation Research and Testing Office, they have been continuing work begun earlier by John

C. Williams and reported in 1977 (ACS Advances in Chemistry Series 164) on the use of magnesium compounds in paper to deactivate transition metals like copper, iron and manganese and keep these metals from catalyzing oxidation of the cellulose. (Magnesium is often preferred over calcium for aqueous deacidification because it supposedly offers this additional protection.) They doped paper with copper and then dipped it once in one of eight deacidification solutions, expecting to confirm the common belief that magnesium, unlike calcium and other metals, somehow prevented this catalyzing effect. What they found was that calcium bicarbonate was almost as effective as magnesium bicarbonate, though other calcium solutions were not. The principle at work seemed to be that any bicarbonate compound easily washed the copper out, because they got similar protection from zinc bicarbonate and sodium bicarbonate. Magnesium acetate gave protection too. One implication of this, he said, was that aqueous magnesium solutions should not be used to deacidify verdigris, because it might wash the color right out.

The ongoing adhesive testing program at CCI has come up with some disturbing results for conservators, as we learned in Jane Down's "Report on Adhesive Testing at the Canadian Conservation Institute." So far the only types they have tested are PVAs and acrylics, but others will be added later. The adhesives, in emulsion and film form, are tested for pH, emission of harmful degradation products, flexibility, strength, softening temperature, shrinkage, removability and discoloration as they undergo dark aging (22°C, 45% RH) and fluorescent light aging (700-800 lux, 190 microwatts per lumen, 22°C, 45% RH). Only the stability of the adhesive itself is tested, not an adhesive/substrate system. The "acceptable" pH range for adhesives to be used on either leather or paper was 6.0-%5. Most PVAs were either too acidic to start with, or got too acidic as they aged, whereas acrylics ranged from a pH near 4 up to 10. Light-aging tends to lower the pH of both types, sometimes by two points over the two-year testing period, but AYAA and AYAC PVAs start acidic and go toward neutral as they age. Most of the Rhoplex adhesives fall into the acidic range with aging. This news will probably prompt a search among conservators for more stable adhesives for heat-set tissue. Jade 403, Beva 371, Acryloids B-67 and B-72 and other adhesives less familiar to book and paper conservators had acceptable pHs after aging--so far. Emissions of acetic acid from PVAs and acrylic acid from acrylic adhesives were not seen as serious or definite threats; lead (usually very sensitive) was not affected.

Adhesives that were among the 135 considered for testing, before screening down to 50, were Gaylord Magic Mend, Jade 454, Elvace 1874, Solomon's Velverette, Promatco A-1023, Pliantex, unsupported Texicryl, Document Repair Tape, and Filmoplast P. Planatol was not considered, perhaps because it did not belong to one of the two types. The names of the adhesives chosen for testing cannot be read from the handout because it has been reduced too far, but no adhesive was dropped if it was the only one of its subtype. Among the PVAs, subtypes were defined by the type of polymer (e.g., "vinylacetate/ethylene/vinylpropionate copolymer) and type of additive or additives (23 categories).

Robert Feller gave two papers co-authored with Lee and Bogard on the effect of light bleaching on paper and on model compounds (residues of cellulose and' hemicelluloses). The main variables were: light wavelength, pH of both paper and water, brightness of paper or model compound, type of paper (groundwood, unbleached, filter), thermal aging or lack of it, and presence or absence of water. He called the work a "preliminary examination," bet as usual it was thorough and convincing. One of the conclusions from the first paper laid to rest the debate between conservators and scientists over whether light bleaching of paper submerged in an alkaline bath degraded the paper. He said, "Wet light bleaching doesn't damage paper.... I can hardly believe this as a chemist but the evidence is that...."

Other conclusions: UV light bleaches most papers but darkens paper with lignin in it. Alkalinity by itself darkens paper to start with, but it accelerates light bleaching. Wet papers bleach faster.

Ian Hodkinson described the program for library and museum conservators at Queens University (described by Bob Parliament in this Newsletter, Oct. 1987, p. 112-113), and told something about previous graduates and their projects, then said that Bob Parliament, who had set up the program there for book and paper conservators, had left during the summer. Only one student had registered in September, and the continuation of the program depended largely on whether a new professor of conservation of paper objects can be hired.

Plenty of time on the program was set aside for consideration of conservation dilemmas and debates on what are usually referred to as ethical issues. John Barton described nine compromises of the sort that are common in conservation treatment, exhibition and education. (Incidentally, there are compromises in preservation too, but they have not been discussed so far at conventions.)

There were two panels that raised lots of questions. The first was "The Ethics of Disbinding Books, Manuscripts, Atlases, Note-books, Sketch-books, etc. ," chaired by Don Etherington and made memorable by Joyce Banks' adamant stand against any kind of disbinding, which she equated with pulping. She was opposed to removal of folded maps from books, even if it was impossible to get them back in the same cover after mending. She was an advocate, but not the only advocate, of leaving things like they were and letting readers use then. Sample comments from panelists and members of the audience:

It doesn't wear out books to use them.

Even graduate students shouldn't be given access to original works of art.

If you have to separate them [a folded map and a book], that's the best way to go. But to keep people from using them is unethical.

The other panel was on 'The Conflict Between Conservation Treatments and the Preservation of Artists' Materials and Intent." At the end, written questions were submitted from the audience. Craigen Bowen got one that read, "Would you reattach scotch tape?" She said, "If it was meant to be there, maybe. The person who asked this question should answer it. I'd have to see it to know." A conservator stood up and said, "I asked that. The artist, if still alive, should be confronted with it: 'You created it, you fix it'".

There were three talks or demonstrations relevant to the moist treatment of moisture-sensitive paper (Flieder, Keyes, and Weidner); at least six on tools, equipment and methods (e.g., Futernick, Segal, Weidner and Michalski); three on surveys and treatment projects (Schrock, who handed out a survey form and a good bibliography on conservation of architectural drawings; Hill; and Grant); and four historical papers (Krill, Stevenson, Tremain and Jirat-Wasiutynski). Stefan Michalski has a "book suction table" that lets a conservator do wet treatment on part of a single page without taking the book apart, a device that satisfies a long-standing need. Bob Futernick' a handy tips were valuable as usual, but you had to be there, and you had to have experience with the operations they relate to. He did say, however, that he would like to share his computerized documentation and reporting program, which he calls "push-button recording," and which has some very user-friendly features, including putting the location of a tear into words for you when you touch the screen. He uses a "souped-up" Mac Plus with FileMaker and Hypercard for his new method, which is the next stage after their old canned-phrase system. He will send a copy of the Hypercard disk to anyone who is interested. There is no documentation or manual, but local knowledgeable people can help you set it up. He wants feedback.

John Krill's paper on the early history of artists' papers, 1795-1815, included the social history of the drawing and water color craze around that time, and was interesting even for the nonartist. Mark Stevenson gave an interim report of his ongoing study of the treatment of prints during the 350 years prior to 1930, presenting information that has not been brought together before, and which was also interesting to people outside the art-on-paper specialty.

Susan Page described machine-made Japanese paper available in the U.S. and suitable for aqueous and heat-set linings, especially for large objects like blueprints, wallpaper, large posters, and roll petitions. Some of it was better than the corresponding handmade paper.

For readers who may want to contact some of the speakers, here are the addresses of the people who are not in the AIC directory. Down, Tse and Michalski are at CCI, 1030 Innes Rd., Ottawa, Ont. KlA OCR. John Barton is at the Provincial Archives of Ontario, 77 Grenville St., Toronto, Ont. M7A 2R9. Cathy Craig-Bullen is at the National Archives of Canada, 395 Wellington St., Ottawa, Ont. K1A 0N3. Vincent Daniels is at the British Museum, Dept. of Conservation, London WC1B, 3DG Chandru Shahani is at the Library of Congress, Preservation Research & Testing Office, Washington, DC 20540. Ian Hodkinson is at Queen's University, Art Conservation Program, Kingston K7L 3N6.

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