Research On The Key Technology Of Cellulose Acetate Film Archive Acetic Acid Syndrome Treatment

The photographic film is a kind of image archives,which have special shape and distinct scientific technological content.It plays an important role in all aspects of political,economic,educational,military,medicine,art and even the people daily life since the photographic film was prepared before 100 years.Therefore,there are a large number of photographic film archives including cine film,microfilm,photographic film,aerial film and so on.Especially,the cine film and microfilm have abundant content and large numbers.However,the scratching,fading,acetic acid syndrome and other diseases phenomenon would occur because of the quality of the main composite materials and their preserving environments during the using and keeping.Among them,the acetic acid syndrome is the most serious problem.The acetic acid syndrome,known as cancer of the cellulose acetate-based films,seriously harm to the safety of the film archives.At present,there is no better treatment to solve this problem,only by controlling the preservation conditions.The acetic acid syndrome is produced from the hydrolysis of the cellulose triacetate ester.The symptoms of acetic acid syndrome is mainly presented as:the film emitting a acetic acid smell,the large amount of white crystals precipitation on the film surface,and even serious distortions,liquefaction of the emulsion layer,and decomposed into fragments and even self-destruction finally.The mechanical strength,the image records of the film,etc.are damaged in different degree,and the distortions is the most serious problem caused by the acetic acid syndrome,which turn the copying,digital conversion and restoration of film inconvenience and even impossible.Based on damage situation of the acetic acid syndrome,the changes in structure and properties of the film after the acetic acid syndrome and the harm of the acetic acid syndrome have been studied,and the preventive measures are explored.The main components of precipitated crystals on the film surface are characterized as the triphenyl phosphate,and the n-butanol,isobutanol are selected as the plasticizer cleaning agents,which can remove the plasticizer precipitation,and the film can not be destructed.Because film still has a certain amount of thermoplastic after the acetic acid syndrome,the repairing technical conditions of the distorted film are designed.It is proved by many experiments that the above method can effectively restore the distorted shape of film.The protective agent of the acetic acid syndrome film is prepared,which could prevent the restored film from precipitating the crystal and distorting again.Chapter Ⅰ:It mainly introduces the construction and material composition of the film,imaging principle,the main diseases of the film archives,domestic and international advances research in the field,the subject selection and research ideas of this dissertation.Chapter Ⅱ:The causes and influence factors of the acetic acid syndrome are analyzed,and the changes in structure and performance of the cellulose acetate-based films after the acetic acid syndrome are characterized by super depth of field microscope,scanning electron microscopy,infrared spectroscopy,thermal analysis.The harm of the acetic acid syndrome has been studied,and the preventive measures are explored based on domestic and foreign research and preservation practices.Chapter Ⅲ:The main components of precipitation of crystals on the film surface are characterized as the plasticizer triphenyl phosphate by infrared spectroscopy,spectrum analysis,NMR,mass spectrometry and other analytical methods.A variety of commonly used organic solvents were selected as the plasticizer cleaning agents,it is proved by experiment that the n-butanol and isobutanol can effectively remove the plasticizer precipitation as the plasticizer cleaning agents.At the seme time,the film can not been destructed.Chapter Ⅳ:Based on a certain amount of thermoplastic for the the acetic acid syndrome film,the restoring test machine of the distorted film is designed.The heating temperature,pressure stress and the time of the distorted film are optimized.The experiment shows that the mechanical strength of the film can not been changed by the above method.Chapter Ⅴ:The protective agent of the acetic acid syndrome film is prepared.The main ingredient of the protective agent is ethyl cellulose,appropriate amount of fumed silica and antioxidants.The effects of film-forming,the changes in mechanical strength,durability and other aspects of the film are studied.