Investigating Crayon Removal from Paper Based Japanese Prints
Hsin-Chen Tsai, Andrew W. Mellon Conservation Fellow, Museum of Fine Arts, Boston
Problem: Crayon “graffiti” on 20th century Japanese prints by Munakata Shiko. The prints were mounted to screens, and the graffiti appeared at about 4 ft. from the ground—around the same height as a child. Unlike graffiti on a painted wall, however, crayon does not come off of printed paper quite as easily.
Experiment: Mock-ups were created with Japanese paper, printed with black sumi ink, then colored over with both waxed-based and water soluble crayons. Possible solvents were chosen from the wax section on the Teas diagram and included petroleum ether, mineral spirits, toluene and xylene. These solvents were tested in three situations:
- Solvent on a swab
- A bath of water and solvent, followed by blotting of the stain
- Damp blotter surface with local application of moisture and solvent, followed by blotting of the stain
Results:
- Solvents alone did not reduce crayon to a satisfactory level; mineral spirits created a transparent stain visible through the paper
- With the bath, it was impossible to control the amount of solvent used, but the overall result was positive
- Crayon was lifted locally, but also migrated along with solvents to form tidelines
The ultimate solution was the use of a water-based treatment with toluene and xylene, such as that used in Experiment 2. For best results, Hsin-Chen suggested first manually reducing the graffiti with a kneaded eraser and scalpel.
The Relationship Between Inherent Material Evidence in Cultural Heritage and Preservation Treatment Planning
Lynn Brostoff, PhD and Fenella France, PhD, Preservation Research and Testing Division, Preservation Directorate, Library of Congress
Problem: A 1513 edition of Ptolemy’s Geographia was in poor condition, and puzzled conservators as to its history. Lynn set out to answer many questions, including: what was causing seven of the forty-seven maps to deteriorate?
Experiment: Using XRF, the pigments and paper were analyzed on maps of both good and poor condition, and in various areas of the sheet.
Results: Maps in poor condition contained Fe and Cu—two elements that cause the degradation of cellulose—as wells as K, S and Al—elements that together form potash alum. The pulp repairs and gutters of these pages, however, did not contain such elements and remained in good condition. It was decided that the paper quality used in these cases was poor, requiring a past restorer to “strengthen” the bound papers with a potash alum solution; gutters were not coated, and mends were made with untreated pulp.
This information, along with the result that one of the green pigments contains copper, answers the question about the differing quality in the maps, and also informs conservators for treatment planning.
Light Bleaching: Scientific Investigation of Various Effects on Different Properties of Several Old Papers
Marion Verborg, Paper Conservation Fellow, Conservation Center for Art and Historic Artifacts
Problem: As part of her graduate conservation program at the Sorbonne, Marion carried out research on the history and effects of light bleaching.
Experiment: Using an array of papers of varying quality (wood pulp and rag paper) and age (from late 19th c. to present day), Marion created test strips and subjected them to different conditions:
- A 25 min. wash in condition water
- A 4 hr. wash in conditioned water
- Washed in conditioned water, dried, then exposed to light
- Washed in conditioned water for 4 hrs, then exposed to light while still immersed in the bath
The paper samples were aged in an oven before undergoing a serious of tests including pH, tensile strength, color, and degree of polymerization.
Results: Light exposure in dry conditions can be extremely damaging to paper, all wood pulp papers become weak and yellow over time no matter what the level of treatment, and light bleaching is generally an efficient treatment for rag papers because it produced an aesthetically pleasing result without harming the paper extensively.
**Comments/questions from the audience:
- Does the hydrogen bonding need to be reset after treatment?
- Magnesium can be used as a substitute for calcium when conditioning water baths, and produces better results after aging
- Paper needs to be rinsed thoroughly (3 times) after bleaching to prevent color reversion
A Comparison of the Use of Sodium Metabisulfite and Sodium Dithionite for Removing Rust Stains from Paper
Seth Irwin, Alaska Paper Conservation
Problem: While conducting a treatment on a highly rust stained paper document in Petersburg, AK, Seth discovered sodium dithionite (SD) as a reducing agent to convert insoluble Fe (III) into soluble Fe (II). The setback: dithionite is expensive and toxic, and could not be shipped to the location before his treatment deadline.
Experiment: What is a suitable alternative for SD? With one more oxygen, sodium metabisulfite (SM) is a less expensive and non-hazardous option commonly used in wine making. In order to test SM as a viable solution, Seth rusted up some paper, and then used both SM and SD solutions (separately, with EDTA as the chelating agent) to create a comparison.
Results:
SD- best when cost is no issue ($7.00 for a 1 liter 5% bath); requires ventilation and HAZMAT shipping, but removes corrosion in 4-6 hours.
SM- cheaper ($1.20 for a 1 liter 10% bath); takes longer, and only removes light to medium stains, but could possibly be done on a suction table rather than in a bath if there are chemically sensitive areas of the paper.
**Comments/questions from the audience:
- A commercial product called White Brite exists, and may also remove rust stains in paper.
Treatment of an Oversize Rare Book: Research and Decisions on Rebinding (Pre-program Student Paper)
Evelyn Mayberger, Intern, National Museum of the American Indian; Betty Fiske, Historic Odessa Foundation; Michelle Biddle, Olin Library, Wesleyan University; Abigail Quandt, Walters Art Museum
Problem: Cosimo Bartoli’s book The Architecture of Leon Batista Alberti, in Ten Books, of Painting, in Three Books, and of Statuary in One Book was in poor condition and required stabilization. With this opportunity at hand, pre-program intern Evelyn Mayberger worked with Betty Fiske at the Historic Odessa Foundation to research the history of the book before treatment.
Treatment: Evelyn visited several collections to learn about the types of bindings used for this book, and how conservators had approached their treatment decisions. After consulting with Abigail Quandt and Michelle Biddle, Evelyn and Betty spent a total of 462 hours on the treatment of the book, including washing, tape removal, sun bleaching, mends and infills, guarding, sewing, lining and board covering (!) Oversized plates that had been sewn into the binding were restored to fold outs, and the binding was returned to what Evelyn deemed historically appropriate.
Results: It was discovered that all editions of the book had been re-bound, and most contained 6-7 sewing stations. Also of note, the first edition was printed in parallel Italian and English, which caused later editions to include all plates facing recto.
For more notes on these talks, and others, please visit Preservation & Conservation Administration News.