Abstract
Ancient fiber products were remained on archaeological metal objects such as a sword and personal ornaments. These fiber products were the very precious document which then fiber product manufacturing technique can estimate, but fiber received the rust which occurred to metal objects, and they were changed from the real quality. We tried to confirm the mechanism of deterioration for fiber on metal objects. We reproduced silk (non-refinement fiber) textile bags (4cmx4cm) because of covering with standard plate of copper (JIS : C1100P) / iron (JIS : SS400) and investigated the influence that rust generated to metal gave silk fiber. After covering metal plate with silk bag, these
were spotted chemical reagent (NaCl and Na2SO4 3wt% aqueous solution) and were revealed in constant (25 degrees
Celsius / RH90%) for 12weeks and it caused metal corrosion state in 3weeks. I confirmed change in deterioration of silk
fiber used OM / SEM observation and X-ray analysis. The changes for color parts (light green or brown) of silk bags
were seen and not only metal corrosion but also Calcium products were confirmed on silk fiber using X-ray analysis.
There were estimated that the beginning of deterioration is reaction of metal ion and anion and second step were
reaction of Calcium ion from silk sericin and anion.
