A written real aged paper sample from the XVIII century; Breviarium romanum ad usum fratrum minorum

Ingredients

Cellulose nanocrystals (CNCs), S_CNCs, N_CNCs, Gellan hydrogel

Preparation Steps

Original Recipe Text

The conservation method utilizes Cellulose Nanocrystals (CNCs) applied to aged paper from the 18th century (p. 16). S_CNCs (sulfated) and N_CNCs (neutral) are compared. S_CNCs form stable suspensions due to charge repulsion and self-assemble into thin films covering the paper surface, while N_CNCs bind strongly to individual fibers without forming self-standing films. Reversibility is achieved via removal with Gellan hydrogel and an electrochemical tool (p. 16).

Evidence

"Operamolla et al. [45] proposed an innovative strategy to improve the mechanical properties of paper artwork. In their study, sulfated CNCs (named S_CNCs) prepared by sulfuric acid hydrolysis form stable colloidal suspensions in water due to surface charge repulsion... this restoration strategy is reversible since CNCs can be removed by Gellan hydrogel with an electrochemical tool."

Remarks

The study emphasizes the use of CNCs to maintain optical quality while enhancing mechanical characteristics. Neutral CNCs are noted as safer for long-term conservation because they do not compromise the pH of the paper during accelerated aging, whereas S_CNCs may decrease paper pH over time (Section 3.3). Figure 5 shows the visual results of the Breviarium romanum treated with N_CNC vs. S_CNC (p. 17).