Caring for Yale Library’s Paper Collections

Paper and Photograph Conservator Marie-France Lemay working in the Gates Conservation Laboratory

Yale University Library has a rich collection of manuscripts, documents, and art on paper that includes maps owned by George Washington and Harlem Renaissance posters. YUL’s paper conservator, and technician Frances Osugi, use a variety of techniques to preserve collections for future Yale students, faculty, and researchers. Treatments mend tears, fill areas of loss, remove damaging tapes, and reduce disfiguring stains. Conservation staff must carefully consider the stability of inks and colorants and balance the strength of new repair materials to fragile originals to avoid new damage. Repairs must be visually sympathetic with original papers, but not invisible. All the work is undertaken in consultation with collection curators to consider the anticipated use of the object and its value.

Aqueous Treatments

Papers from the late 19th and early 20th century, made from wood pulp, contain lignin, a compound that is highly susceptible to chemical change. Lignin leads to high levels of acid in papers and results in embrittlement. Washing paper removes acidic byproducts that cause staining and discoloration. Conservators must test all media before washing as some inks and colorants will bleed when they encounter water.

Werner Haun, Assistant Chief Conservator for Collections Conservation & Housing, assisting with the washing of an oversized poster for the 1908 musical The Red Moon


Japanese tissue, a traditional paper made up of plant fibers, is used to mend tears and fill areas of loss. Tears and losses along the edges of this brittle piece from the James Weldon Johnson and Grace Nail Johnson Papers were mended with toned tissues and reversible adhesives. The work was undertaken in preparation for the item’s inclusion in an exhibition in the Fall of 2016.  

Before Treatment

After Treatment

Oversized Items

The materials treated by conservation staff come in all sizes, from the 8 x 10 inch pieces above, to large scale items, like maps and posters. These larger items are typically lined with large sheets of Japanese tissue. These linings provide strong, flexible support for fragile paper items.

Conservation Technician Ansley Joe (left) and Paper Conservator Marie-France Lemay preparing a Japanese tissue lining for an oversized brittle poster

The Traveling Scriptorium

The Traveling Scriptorium contains samples of the materials and techniques used in medieval book production.

Our paper conservator, along with other lab staff, gives presentations to Yale classes on historical inks and pigments using the Traveling Scriptorium, a Medieval manuscripts material teaching kit created in the Library’s laboratory. Each year staff add new elements to engage students in hands-on exploration of the manufacture of the manuscripts they study from the collection. Teaching guides on Medieval bookbinding and ink and pigment recipes are available online and in print for Yale classes.

The kit includes several sample sets of traditional inks and pigments, as well as examples of various raw materials used in Medieval manuscript production.

Prev Next