A month ago we discussed water damage to Nahari ink. I then suggested drying the affected Sefer Torah in the sun, hoping that the ink will dry and be less susceptible to water damage.
I made an experiment. The following was written with new-fresh Nahari ink on klaf.
It was then allowed to air dry for two weeks.
Then, the letter ד was wetted with water. Some ink spread on the klaf.
The klaf was then baked dry at 100 degrees C for 2 hours, to make sure the ink is really really dry.
The klaf was then taken out and allowed to stand in room air for 2 hours.
Then, the letter ר was wetted with water. Some ink spread on the klaf, with a different spread pattern.
It appears that drying the ink did not help. I now suspect that drying the Sefer Torah in the sun will also not help.
Why does the ink spread even after good drying?