Ownership Marking of Paper-Based Materials
Traditional collecting practices have often included ownership marking of items, such as bookplating or stamping. One argument for ownership marking is that it can help deter theft and establish ownership in the event of theft. Theft, however, occurs regardless of the presence of ownership marks. Therefore, ownership marking primarily for theft deterrence requires careful consideration, especially as the mark should be indelible to be useful in this manner.
Long-practiced options for permanently marking paper-based items include embossing, punching or perforating, and ink stamping. Many libraries today mark ownership by edge ink stamping and use electronic strips for theft deterrence.
Library of Congress ownership Marking Ink
For edge stamping the general collections at the Library of Congress, the Preservation Directorate developed, in cooperation with the United States Government Printing Office, a permanent, indelible, neutral-pH ink that will not bleed if exposed to water or other solvents, that is resistant to fading, and that has not demonstrated adverse affects on paper substrates during testing. The Library of Congress does not necessarily recommend ink stamping rare or unique collection items. Library, archive, or museum institutions may request this ink (specify blue or black) by sending a contact name and institutional postal address to Ask A Librarian. If possible, we ask international institutions to provide a U.S. postal address as the ink and the postage is provided free of charge.
Additional information about the ink
Requires a special stamp pad made of balsa wood. Balsa wood ink pads are available from online archival suppliers (Internet keyword search: "Clear Print wood block stamp pad archival inks") or can be made easily by cutting a ½" thick layer of endgrain and sanding smooth; the end grain is the inking surface. The pad should be kept in a container.
Requires a specially cut stamp. The best imprints are made by stamps cut from rubber with simple, thin, sans-serif, all capital letters, text-only designs.
When properly applied, the ink does not bleed on most papers; the ink may bleed slightly on exceptionally thin or porous papers; the ink does not apply well on highly calendared or coated papers.
Requires a relatively long drying time. If page stamping, the book should be left open overnight to dry to prevent offsetting; this requires a lot of workspace.
Application Tips
The best way to apply the ink to the balsa pad is with a plastic or wooden stick that is approximately 1/8" in diameter. Dip the stick into the ink. Allow excess ink to drip from the end of the stick back into the bottle. Roll the stick across the pad to distribute the ink evenly. The edges of the pad do not require inking. Ink area of pad only slightly larger than the stamp. Overinked pads compromise the quality of the stamp mark and can result in bleeding or strike-through. Allow the inked pad to stand for 30-60 minutes before using in order to permit migration of the ink into the pad. Practice using stamp on scrap paper before marking original. Clean an overinked pad by repeatedly stamping discard paper.
New balsa pads may require more frequent re-inking until the wood block is saturated or "primed." Once primed, the inked pad can be refreshed by applying one drop of water one week and one drop of ink the following week or as needed. The water can be applied with a medicine dropper. Use the ink stick to distribute the water over the surface of the pad.
If page stamping (instead of edge stamping), work on a flat, smooth surface to enable the stamp to touch the paper squarely and evenly and to prevent creasing or other topographical damage. If page stamping in a bound item, a piece of acid-free mat board behind the page can provide a flat, smooth surface for successful marking.
Placement of Mark
Institutions place ownership marks according to objectives, established practice, and common sense. Common practices include placing the mark where it: is easy to locate (e.g., in the same place on the same page of every book); is readily and easily visible (e.g., edge stamping of books); does not deface the item; does not obscure image or text; is on a blank side when available; is in an area of the page that is not blank/white on the other side (or the stamp will be more visible from the other side).
Marking rare or unique collection items
It is best to discuss the use of the Library of Congress ownership marking ink with your institution's conservator or preservation librarian before marking any rare or unique items.
