Exhibition presented by Carole Jeanneret
from the "Open Book" workshop
24 Rue de Lausanne in Fribourg
"The mission of the conservator/restorer: what if your books could last another 100 years?"
From June 3 to 27, 2026 at L'Atelier, Place Notre-Dame 16 in Fribourg
Aqueous cleaning
What is this ?
Aqueous cleaning is a conservation treatment that involves exposing a document, most often paper, to controlled contact with water to remove some of the soluble degradation products, acids, and certain soils embedded in the fibers. It is therefore a more thorough process than simple dusting and is only carried out after a very careful examination of the condition of the paper and inks.
In theory, aqueous washing aims to remove acidic substances and soluble impurities that weaken the substrate, while improving its chemical and mechanical stability. It may be followed by deacidification and sometimes re-sizing, depending on the chosen protocol. In practice, however, it is not a “wash” in the common sense, but a controlled physicochemical treatment.
Be careful!
Wet cleaning is only considered if the substrate and inks can withstand it! But this method requires prior testing, because some inks, some dyes and especially unstable iron-gall inks can react very badly to water.
For printed or handwritten paper
Controlled humidification or washing of paper is reserved for specific cases, when the conservator has verified the ink retention and the mechanical stability of the support. This type of intervention is carried out according to a very strict protocol, with rinsing, controlled drying, and often flattening or pressing. In practice, an old document is not "water-cleaned" simply for the sake of washing: it is only treated if it genuinely improves its condition and if the risk is acceptable.
For books and bindings
For books, cleaning must take into account not only the pages, but also the edges, endpapers, hinges, binding, and materials such as leather, cloth, or cover paper. Some binding surfaces do not withstand moisture well, and wet cleaning can distort the volume, weaken the adhesives, or damage the cover materials. This is why dry cleaning remains the most common method before any more intensive treatment.
Limits and precautions to take
A good cleaning is never a "deep cleaning." Avoid household cleaning products, excessive water, vigorous scrubbing, abrasive sponges, and any method that might set the dirt instead of removing it. Also consider the possible presence of mold, sensitive inks, unstable pigments, old glues, or very brittle paper, as these factors may contraindicate wet cleaning.
Paper bleaching treatments should be avoided, as they profoundly alter the fibrous structure of the substrate, permanently weakening the components and accelerating its degradation process.
Professional logic
In a professional setting, the process generally follows this procedure: examination of the object, stability testing of the inks and colors, dry cleaning if possible, and only then, if the condition of the support warrants it, potential humidification or controlled aqueous treatment. The aim is to choose the least intrusive intervention compatible with the preservation of the object.
The equipment used:
Spray for the necessary pre-moistening before bathing.
Document bath tray
Made only with inert materials: polyethylene, Teflon.
Let's work together
Contact us so we can work together.
