It can be, but it will be almost impossible to read and impossible to photocopy.
The standard legal signature must be in black or blue-black ink. However, it can certainly be shown as evidence of agreement or contract, particularly if it can be seen by ultraviolet light or through another means.
With white ink on white paper.
the ink will soon fade, the rubber will lose its strechiness and the paper will stay white
The light is absorbed by the black ink and reflected by the white paper surrounding the ink. That is why you can see the ink clearly.
Shortly after white ink, which was in need of replacement as no one could read it on the era's white paper.
Yes black ink radiates more heat than white paper. This is because more heat is absorbed by black ink more than white paper and it is required to radiates more heat due to its heat capacity
Only if white space on your paper is the problem.
i want correct answer
Take a sample of the paper and soak overnight in water, and soak another piece in alcohol. If ink had been present, either solution should be discoloured. If in doubt, use plain paper: white or brown wrapping paper.
how do you remote dry ink from paper
Ink. Just as a pen writes on a paper with ink, a pen contains ink to write or draw.
Well, for small marks, I know some professional illustrators scrape the surface of the paper with a sharp razor's edge to remove ink. This is sometimes used because white-out may not match the color of the paper used. I don't have a source to give you, though, sorry.