不同调胶浓度下莫高窟壁画颜料颗粒度与病害关系研究

A Study on the Relationship between Pigment Particle Size,Glue Concentration and the Deterioration of Mogao Cave Murals

莫高窟壁画在千百年自然因素侵蚀作用下,导致粉化、脱落、起甲等多种病害,其中颜料层粉化脱落直接导致壁画画面的模糊甚至消失,严重影响壁画的完整保存。本研究以莫高窟常见的两类矿物颜料石青和石绿为研究对象,通过室内模拟老化实验,以微观形貌、色度变化以及病害表现形式为表征手段,研究不同颗粒度矿物颜料在多种胶浓度下的病害特征。结果表明,矿物颜料颗粒越粗,越容易发生粉化脱落病害,胶结材料浓度直接影响壁画颜料层病害表现形式,胶浓度较低时,颜料层主要病害表现为粉化脱落,胶浓度较高时,易发生开裂起甲病害。

The murals of the Mogao Caves have experienced centuries of erosion from various natural factors,which has resulted in various forms of deterioration such as powdering,paint loss and flaking.Powdering and loss of paint in surface pigment layers leads directly to the blurring and sometimes even the disappearance of the murals,and constitutes one of the greatest dangers to the continued conservation of these historical artifacts.This study focuses on the mineral pigments azurite and malachite,which are common in Mogao murals,to analyze the deterioration mechanisms affecting pigments of different particle sizes,while also taking into consideration the various glue concentrations that hold the pigments together.Research methodologies include simulated indoor aging experiments,microscopy and chrominance.The results indicate that mineral pigment particles that are larger and coarser are more prone to powdering and paint loss.Additionally,the concentration of the binding material directly affects the form that deterioration takes.When glue concentration is low,powdering and paint loss are likely to appear;when glue concentration is high,the murals are more prone to cracking and flaking.