Application of Ionic Liquids in Paper Properties and Preservation

Abstract

For centuries, paper has been an important medium of information. Currently, the basic risk to the paper collection is "acidic paper" and the action of enzymes secreted by microorganisms on them. In order to 'prolong life' of these materials, in recent years, various chemical compounds have been used. In this chapter, ionic liquids (IL) are explored as substances for deacidification of paper and its conservation, including antifungal activity. The use of these substances in the manufacturing of paper is possible, but the ingredients play an important role. Imidazolium IL cause an increase in the pH (deacidification) of historical papers and do not cause worsening of their strength properties, but these compound can cause a colour change. Benzalkonium DLlactate and didecyldimethylammonium DL-lactate and derivatives of 1,2,4-triazole are used as effective inhibitors of growth of moulds on paper. The best antifungal activity in these ionic liquids is observed in the paper pine at a concentration of 5% and weakest in the samples from the pulp after chemical-thermomechanical treatment. New paper impregnated with ionic liquids is characterised by an increase in tear resistance, reduction of breaking length and a favourable influence on the paper colour.

Biological Activity of Ionic Liquids and Their Application in Pharmaceutics and Medicine

“…291 For imidazolium ILs with short alkyl chains, the toxicity was found to depend on the chaotropicity of the anion. 292 Antimicrobial properties of ILs were suggested to be employed in the development of new IL fungicides, 293 and in the protection of natural fabric, 294 paper, 295 and metal surfaces 296,297 against microbial growth. Similarly, graft polymers of poly(ionic liquids) were proposed to be used in antibacterial coatings.…”

New protic ionic liquids for fungi and bacteria removal from paper heritage artefacts

“…14 Also, there are several attempts to use ILs for paper conservation. [16][17][18] For example, their low volatility reduces the risks to health and the environment, their high viscosity may inhibit the penetration into the paper layers, and their adjustable miscibility with water or less toxic solvents allows their removal with safer solvents. Also, the antimicrobial activity of ionic liquids has quickly attracted the attention of researchers, since the fungal and bacterial deterioration is one of the main causes of the paper artefacts degradation process.…”

Ionic Liquids as Reconditioning Agents for Paper Artifacts

“…Irrespective of the chosen restoration methods and techniques, they must adhere to fundamental criteria, with paramount importance given to increased efficiency and minimal potential for paper substrate degradation [ 3 , 22 ]. Preserving the original appearance and texture of the material, ensuring long-term stability for any introduced additives or consolidants, and maintaining environmental friendliness with low toxicity are equally pivotal considerations [ 23 ]. These criteria collectively form the essential framework for evaluating the efficacy and sustainability of any restoration approach, emphasizing the need for holistic and conscientious practices in the preservation of cultural heritage materials.…”

“…These criteria collectively form the essential framework for evaluating the efficacy and sustainability of any restoration approach, emphasizing the need for holistic and conscientious practices in the preservation of cultural heritage materials. A critical analysis of the restoration and conservation methods to date for cellulosic materials shows that all traditional methods basically cannot meet all these criteria simultaneously [ 23 , 24 ]. Although these traditional methods have proven effective in a strict sense, such as cost efficiency or end result, they certainly have drawbacks with regard to other aspects.…”

“…Their cleaning and color restoration effect is based on the ability to partly dissolve cellulose and other macro- or small-molecular compounds allowing for the removal of stains and contaminants [ 28 , 29 , 30 ]. They can also be used to impart antibacterial or antifungal character to the paper surface for improved preservation by disrupting the cell wall membranes or by interfering with the metabolism of degrading microorganisms [ 23 , 31 ]. In addition to these properties, they also present low vapor pressure, high chemical stability, tunability and recyclability, which allows for the optimization and reuse of IL-based reconditioning formulations.…”