Analysis And Control Of The Fungal Disease Of The Paper Document "Fox Spot"

In addition to the diseases of water stains,folds,fractures,carbonization and rot,some yellow,yellow-brown and rust colored spots were often found on the paper in the collection and storage of paper archives,books and collection,which affect aesthetics and the mechanical performance of the paper.These spots will continue to spread over time and even penetrate into the pages below,causing immeasurable losses to the value of paper collections and seriously threatening the security of collections.This phenomenon is found in archives,museums and libraries all over the world and is called“Foxing”,as its unpredictable growth characteristics and color are similar to the sly personality and coat color of foxes.At present there is no unified conclusion about its cause.In view of the disease of paper literature which is common and difficult to solve,this study started with a manuscript of the Republic of China with the disease of foxing spots,analyzed the properties and causes of the stain formation,and found the appropriate prevention and control measures.At the same time,the commonly used preservation method of paper literature was evaluated,and some appropriate preservation suggestions were put forward on the aspects of preventive protection of cultural relics.The research mainly includes the following parts:1.The characteristics of the paper with foxing spots were analyzed,and the cause of foxing spots was explored.In this part,the chemical and biological characteristics of a manuscript of Yulin County,Shaanxi Province in 1938 with foxing spots were studied.Herzberg staining was employed for fiber identification,and paper fillers were analyzed by scanning electron microscopy coupled energy dispersive spectroscopy（SEM-EDS）and total reflection Fourier transform infrared spectroscopy（ATR-FTIR）.At the same time,pH test,surface roughness test,X-ray diffraction spectroscopy（XRD）,scanning electron microscopy（SEM）,total reflection Fourier transform infrared spectroscopy（ATR-FTIR）,energy dispersive X-ray fluorescence spectroscopy（ED-XRF）and other methods were used to observe and analyze the foxed and un-foxed areas.And The fungi were cultured and identified for studying the characteristics and cause of this manuscript with foxing spots.The results showed that fungi were the main cause of the foxing spots in this manuscript.2.In order to solve the fungus problem of paper archives with foxing spots,the study of baeteriostasis was carried out.The dominant strains were isolated from several paper files with foxing spots and 2-methyl-4-isothiazoline-3-one（MIT）,1,2-Benzisothiazolin-3-One（BIT）and 5-chloro-2-methyl-4-isothiazolin-3-one（CMIT）/2-methyl-4-isothiazolin-3-one（MIT）complex were used as bacteriostatic agents to study the mildew preventive effects of isothiazolinone compounds on paper archives.The bacteriostatic zone experiment showed that the CMIT/MIT complex had the best bacteriostatic performance.The differences of color,acidity,mechanical properties and microscopic morphology of paper were little after the treatment with isothiazolinone compounds.3.In order to solve the problem of low strength and poor performance of the paper with foxing spots,the study of reinforcement of paper was carried out.According to the research progress of reinforcing methods of paper cultural relics,resin reinforcing method is adopted.Polyvinyl amine emulsion（PVAm）was selected as the reinforcement agent and the suitable concentration was selected referring to the principle of cultural heritage protection“no changing the original appearance”.Taking various paper（Xuan paper,bark paper,bamboo paper and letter paper）as simulation samples,the mechanical properties,pH value,hydrophilic performance,microscopic morphology,crystallinity,thermal stability and aging resistance of different paper before and after reinforcement with PVAm were compared via Fourier transform infrared spectroscopy（FTIR）,X-ray diffraction（XRD）,scanning electron microscope(SEM,X-ray photoelectron spectroscopy（XPS）,solid-state 13C NMR,thermogravimetric（TG）analysis.It was found that the space of the paper fibers could be filled and bridged by PVAm to strengthen the mechanical performance of paper fibers effectively.The crystallinity and thermal stability of the paper fibers were higher after reinforcement with PVAm.And paper fibers were more complete,with less loss of mechanical properties and stronger aging resistance after dry heat aging and wet heat aging.4.The preservation and conservation of paper literature and archives cannot do without containers for keeping them for a long time.The effects of pine preservation on morphology,physical properties,degree of polymerization,crystallinity and durability of different kinds of papers in paper literature and archives were researched.It was found that the folding resistance,tearing degree,tensile strength,whiteness,acidity,degree of polymerization and crystallinity of all kinds of papers decreased to different degrees after treatment with pine preservation.Also the physical properties of the treated samples were lower than those of the untreated samples after dry aging.This indicated that pine preservation will reduce the strength and durability of paper fibers,and have a negative impact on paper preservation.It is greatly necessary for the preventive protection of files and archives in the process of preservation.