皮影原皮老化行为的实验室评估

Laboratory assessment of the aging of shadow puppet leather

通过传统“净皮”工艺得到的皮影原皮,具有质地硬、不易弯折、透光性好、亲水性基团多等特点,不同于蓬松柔软的普通皮革。特殊的工艺过程,使皮影具有特殊的材料性质。但是皮影类文物保护尚未受到学界较多关注,多数研究甚至误将皮影类文物所用皮料等同于其他普通鞣制皮革,忽略其特殊的物质材料基础。因此,本研究将皮影原皮作为标准样品,实施控制变量的样品人工加速老化,结合显微观察、性能测试和红外光谱分析进行评估,探究环境因子在皮质劣化过程中的具体作用偏好。其创新点有二:第一是提出一种适宜于皮影皮质老化、劣化程度的标准量化评估方法——该法取样量少、操作便捷、成本低廉,结果令人满意;第二是基于本评估方法的原皮皮质评估实践,证明即便没有鞣制效应作用,仅经过机械制皮过程,皮质仍具有相当的化学稳定性。

The leather obtained through the traditional technique of“cleaning leather”,used for shadow puppets,possesses unique characteristics,such as a hard texture,resistance to bending,good transparency,and a high concentration of hydrophilic groups,setting it apart from typical soft leather.However,the conservation of shadow puppet artifacts made from this kind of leather has received limited attention in academia,with many studies even incorrectly equating the leather used for these artifacts with regular tanned leather,thereby overlooking its distinct material properties.Therefore,this study employed shadow puppet leather as a standard sample,subjecting it to controlled artificial aging processes and conducting assessments through microscopic observation,performance testing,and infrared spectrometry.This method explores the specific characteristics of environmental factors in the deterioration of leather.This study introduces two innovations:1)it proposes a method suitable for quantitatively assessing the aging and degradation of shadow puppet leather—a method characterized by small sample size,ease of operation,and cost-effectiveness;2)based on this method,the practical assessment of shadow puppet leather demonstrates that even without the effects of tanning,the leather retains a significant degree of chemical stability through the mechanical leather-making process only.