Abstract: An object of the present invention is to provide a novel method for diagnosing film degradation which can identify the degraded state of a film based on a resin more efficiently and reliably than ever. In order to attain this object, a method for diagnosing the degradation of a film based on a resin is adopted, the method comprising using the following analysis method A and/or analysis method B, which is a non-destructive analysis method: analysis method A: confirming the presence or absence of abnormality in the film by visual observation and olfactometry, and analysis method B: confirming the presence or absence of an acid anhydride and a sign of hydrolysis reaction as to the film by Fourier transform infrared spectroscopy analysis.

Abstract: The present invention provides a film deterioration preventing material for using together with a record storage film having a triacetyl cellulose film as the base film thereof, wherein the material includes an alkali metal carbonate or an alkali metal hydrogen carbonate as an acetic acid gas removing agent to remove the acetic acid gas in an atmosphere. The present invention also provides an acid gas removing agent to remove the acid gas in an atmosphere, wherein the acid gas in the atmosphere is removed by an alkali metal carbonate or an alkali metal hydrogen carbonate.

Abstract: The present invention provides a film deterioration preventing material for using together with a record storage film having a triacetyl cellulose film as the base film thereof, wherein the material includes an alkali metal carbonate or an alkali metal hydrogen carbonate as an acetic acid gas removing agent to remove the acetic acid gas in an atmosphere. The present invention also provides an acid gas removing agent to remove the acid gas in an atmosphere, wherein the acid gas in the atmosphere is removed by an alkali metal carbonate or an alkali metal hydrogen carbonate.