胶矾水对纸张耐久性的影响机制研究

Effect Mechanism of Gelatin-alum Solution on Paper Durability

胶矾水具有加固墨色、改善纸张抗水性和润墨性的作用,在书画创作、装裱与修复领域应用广泛。然而,胶矾水所引起的纸张酸化劣化问题为书画类纸质文物的保护带来了严峻挑战。为了深入研究胶矾水对纸张耐久性的影响机制,本文以纯纤维素纸为研究对象,将不同浓度的明胶与明矾溶液,单独或混合施加于纸张表面,经加速老化后,从纸张酸度、还原羰基含量、纤维形貌、色度等方面分析纸张性能的变化规律。通过比较不同浓度施胶矾纸张的pH值与还原羰基含量,发现湿热老化条件下,胶矾水中的明矾含量是影响纸张酸化与纤维素降解程度的主要因素。对比分析相同浓度下单独施胶、施矾与混合施胶矾纸张的还原羰基含量,发现明胶在一定程度上抑制了明矾对纸张纤维素的降解能力,从而减缓了纸张的酸降解速率。由于明胶经湿热老化后会显著变黄,纸张中的明胶含量主导了纸张的色差变化程度。本研究加深了胶矾水对纸张降解作用机制的认识,为纸质文物保护中胶矾水的应用提供了理论支撑。

Gelatin-alum solution plays a significant role in reinforcing ink and pigment,improving paper hydrophobicity,and enhancing ink embellish.It is widely used in painting,mounting,and restoration.However,the acidification problem of paper caused by gelatin-alum solution poses a serious challenge to the conservation of paper-based cultural relics such as calligraphies and paintings.To deeply understand the mechanism of how gelatin-alum affecting paper durability,this study selects pure cellulose paper as model paper,and applies gelatin and alum solutions with different concentrations,either individually or in combination,to modify the fiber surface of model paper.After accelerated aging,variations in paper properties are analyzed in terms of acidity,content of reducing carbonyl groups,fiber morphology,and chromaticity.By comparing the pH values and the content of reducing carbonyl groups of papers treated with various concentrations of gelatin-alum solution,it is found that under wet-heat condition,the concentration of alum in solution is the primary factor that affects paper acidification and cellulose degradation.By analysis of the content of reducing carbonyl groups in papers treated with gelatin,alum,and gelatin-alum solution,it reveals that gelatin can mitigate the ability of alum to degrade cellulose,thereby slow down the rate of paper acidification.Since gelatin tends to yellow significantly after accelerated aging,the amount of gelatin in the paper primarily dictates the change of paper chromaticity.This research deepens the understanding of the degradation mechanism of gelatin-alum treated paper,which provides theoretical support for the application of gelatin-alum solution in the preservation of paper-based cultural relics.