Most people have heard the terms vellum and parchment, but few know that these writing surfaces were originally made of animal skin. Parchment was originally any animal skin that had been readied for writing, while vellum referred specifically to “paper” made from calfskin. (Calf in Latin is vitulus.) Just as calfskin leather is categorized as a superior form of leather, vellum is the highest quality of parchment. Some steps in leather and parchment/vellum preparation are the same (removing hair, for instance), while others are unique. Leather is tanned and limed, while parchment is just limed. This means parchment often reacts to changes in humidity and is not waterproof. Business disaster recovery companies must be cognizant of these properties when providing parchment and vellum document restoration, as explained below.
Both parchment and vellum are prepared by removing skin from hair; stretching skin against a frame; and alternating between scraping, wetting and drying to create a smooth, durable writing surface. These materials were known to be durable, so they were reserved for the most important documents. The United States Constitution is written on parchment, for instance.
Parchment and Vellum Repair
Although writers in the Middle Ages praised parchment and vellum as capable of lasting a thousand years, damage sometimes occurred.
Repairing tears. Traditionally, vellum and parchment document restoration involved hand stitching any tears. Today, gelatin or other animal-based products are often used to mend tears in parchment and vellum.
Flattening curls and creases. If the entire document requires flattening, document restoration experts may choose to place the document in a humidity chamber. Once the document has been thoroughly moistened, clips may be used to stretch if out. An even safer method is to flatten the document by hand and then attach it to a suction table with polyester strips, which are easy to remove once the document has dried.
When only one or two creases must be removed, an isopropyl alcohol mixture may be applied with a cotton swab directly to creases. Next, the business disaster recovery professional would pull on either side of the crease to gently flatten it by hand.
Replacing missing areas, or infilling. This most extreme form of parchment and vellum damage is also the trickiest to repair. Ragged edges and holes may be “infilled” with ground-up animal hide, silk cloth or Japanese paper inserts. Suction tables are often used for infilling as well.
Don’ts for Repairing Vellum and Parchment
Vacuum freeze-drying should be avoided. Parchment will not stand up to this repair method.
Avoid using starch paste, which creates a humidity imbalance and changes the structure of nearby parchment or vellum.
The business disaster recovery experts at Polygon provide top-of-the-line parchment and vellum repair. Libraries and museums rely on our document restoration services to repair sensitive, significant documents. Unlike many business disaster recovery companies, we are equipped to provide both vacuum freeze drying (best for pulp-based paper) and desiccant drying (best for vellum and parchment). In addition to assisting libraries and museums that have already experienced a disaster, Polygon helps these institutions prepare by cataloging delicate documents; noting insurance carriers; and taking other steps to ensure fast, effective document restoration.
[ Photo by: kevinzim, via CC License ]