A new family of high viscosity polymeric dispersions for cleaning easel paintings

Gellan hydrogel as a powerful tool in paper cleaning process: A detailed study

“…Due to their high retention power and their viscosity, the penetration of these liquids into the paper sheets can be significantly reduced, therefore minimizing paper fibers swelling [4][5][6][7]. However, a complete removal of these gels often requires an abrasive mechanical action (i.e., removal with a brush or by wet cotton swabs), which is often unsafe for the artwork.…”

“…At the same time, gel residues can induce dangerous microbial growth [8,9]. To overcome this drawbacks, highly rigid and film forming hydrogels may represent a useful alternative [3,5,7,10], as they can be completely and easily removed in one operation after their application, thus minimizing the side effects already presented. In this contest, a new wet cleaning technique based on the use of a rigid hydrogel of Gellan gum has been recently developed [3,6,11].…”

Poly(vinylalcohol)-borate hydrogels with improved features for the cleaning of cultural heritage surfaces

“…These preparations, based on poly(acrylic acid) as a gelator, minimize the negative effects related to the penetration of liquid, but some residues can remain on the surface after the cleaning process [17]. PVA/borax hydrogels, on the other hand, show mechanical features suitable for easy removal by peeling from surfaces, without need of strong mechanical or chemical actions, and have been therefore proposed for cleaning purposes [14,[18][19][20]. Water/ cosolvent mixtures can be embedded into these high viscosity polymeric dispersions, making them able to soften and swell water-insoluble materials, in a way similar to that proposed in a study concerning the solubilization of hydrophobic substances by hydrotropes in water [21].…”

Sustainability in art conservation: a novel bio-based organogel for the cleaning of water sensitive works of art

“…Cross-linked polyhydroxyethyl methacrylate and polyvinylpyrrolidone were employed for the removal of hydrophilic soiling material applied on acrylic/vinylic layers, showing an high retentive capability of the cleaning agent and a wide versatility as a fluid container [25,26]. Polyvinyl alcohol based hydrogels were for instance employed for the removal of varnishes from tempera paint layer [27,28]. Nevertheless, all above discussed systems still employ water as the main component of the gels, posing risks for the paintings connected to its use.…”

“…In chemical gels the polymeric chains form a strong 3D network cross linked by covalent bonds, that prevents the release of gel residues and is capable to retain the cleaning agent into the network more strongly compared to physical gels. Among this class of gels, acrylamide based hydrogels [24], hydroxyethyl methacrylate polymer semi-interpenetrated with poly-vinyl pyrrolidone chains [25,26], poly vinyl alcohol based gels [27,28] and polymethyl metacrylate organogels [29] were developed. Chemical gels were recently proposed for the cleaning of water-sensitive surfaces thanks to their high retentive capability.…”