纸张和纸质文物是书写和保存信息的主要载体, 具有重要的价值. 酸化降解是纸张目前面临的主要问题之一, 脱酸处理是减缓纸张酸化降解速率和延长纸张保存寿命的有效手段. 因此, 安全有效脱酸材料的开发与使用已成为纸张脱酸研究必不可少的方面. 通常, 氨基/胺类化合物、镁/钙等的碱性化合物因其纸张相容性好、碱性适宜、成本低且安全低毒被认为是较为优良的纸张脱酸材料. 本综述总结了近年来液相脱酸法中常用脱酸材料的研究进展, 包括脱酸材料的分类、制备方法以及纸张脱酸效果与材料结构之间的关系. 最后, 讨论了脱酸材料面临的挑战与发展.

Paper and paper-based cultural relics are of great value as the main carriers for writing and preserving information. Acid-catalyzed hydrolysis is one of the most fatal reactions for paper degradation, and deacidification would effectively slow down the rate of its degradation and prolong the life time of paper. Therefore, the design and application of deacidifying materials with safety and effectiveness is the indispensable requirement for the protection of paper and paper-based cultural relics. Generally, alkaline materials, such as amino/amine compounds, magnesium/calcium hydroxides, oxides, carbonates are the mostly used deacidifying materials for their good paper compatibility, suitable alkalinity, low cost and low toxicity, which exhibit considerable paper deacidification performance. In this review, the recent research progresses of deacidifying materials on liquid phase deacidification process were reviewed, including the categories of deacidifying materials, preparation methods and the relationship between paper deacidification performance and structures of deacidifying materials, finally, the challenges and development of deacidifying materials were also discussed. For classification purpose according to chemical structure, deacidifying materials can be divided into four categories: ionic form, molecular form, micro/nano-scale form and composite form. The deacidifying materials with molecular form can significantly improve the mechanical properties of paper and show a certain deacidification effect, it is necessary to control the improvement of mechanical properties within reasonable ranges while considering the effective deacidification performance. Micro/nano-scale materials with large surface area, good penetration and high efficiency are the widely used deacidifying materials, which can achieve better deacidification effects at lower concentrations. The controlled alkalinity, high dispersion and suspension stability in solvents and uniform distribution in paper fibers of micro/nano-scale materials are highly demanded. Additionally, ionic form materials can interact with paper fibers more evenly through homogeneous deacidification process, but their alkaline reserve is relatively insufficient. And more insight is demanded into the co-existence stability of composite deacidifying materials and its contribution to paper protection.