Study on the Endurance of Archival Handwriting Materials Influenced by Acid

The endurance of archival handwriting materials, an important factor that affects the life of archives, is influenced by the main environmental factors such as light, temperature, humidity, acid, alkali and oxide. The influence of light, temperature, and humidity has been examined deeply whereas that of acid relatively less reported. However, study on archival handwriting materials influenced by acid is important and necessary. Some reasons seem obvious: firstly, in recent years, with industry developing and traffic busy, the concentration of pollutants in air becomes more and more dense and these pollutants could do harm to archives in the form of acid. Secondly, now most writing paper is acid so a lot of archival handwriting materials are in acid environment.

In the view above, seventeen new and traditional types of handwriting materials have been chosen as objects of the study. The experiment method follows industry standard test methods for endurance of handwriting materials influenced by acid. It consists of three groups. The first is about influence on handwriting by different types of acid with the same concentration (pH=2). The second is about influence on handwriting by various concentration of the same acid. The concentration of acid rang from 0.1mol/l (pH=1) to 0.0001 mol/l (pH=4). The third is about influence on handwriting by same acid in different temperature (20-80 ° C).

The variation of color before and after the experiments has been measured according to CIE 1964 L^*a^*b^* color system, then the value of color difference (ΔE) was obtained and statistics analysis was made on experimental results in the light of statistics software-SPSS.

From the experimental results, we could get the facts as follows:

In the handwriting materials of ink, the acid-resistance of carbon ink is the best. As far as ball pen and carbon paper handwriting materials are concerned, the black ball pen, the red ball pen and the black carbon paper are the best, while the blue ball pen, blue carbon paper are bad. For the handwriting materials of computer print files, the acid-resistance of laser print handwriting is the best, next comes the stylus print handwriting. There is a similarity for the property of photocopy and signing pen. For the ink jet print handwriting, its ability of water-resistance is very poor,while acid-resistance is not bad.

Moreover, the endurance of handwriting influenced by temperature and acid co-operation has been studied. And from the results analyzed in statistics, we can conclude that there exist a linear relationship between temperature and the value of color difference (ΔE) in different experimental condition (non-acid, pH=2, pH=3). Only for the factor of temperature, its negative effecting on handwriting is not important if not considering other factors. However, if temperature is combined with acid, it could accelerate the negative effect of the acid and the more high temperature the greater the acceleration.

As the basis for discussion, some acid-prevent measure are put forward. For example: set up acid-resistance grade of handwriting; keeping acid gas away from archives; chose neutral paper as archival writing paper.