but i thought some of the older photography guys who used chemicals mite know
i need to change the ink color on a old u.s map thats come from a book from red to black,the reason is im going to frame it and the red is hard to see,
den 8)
"older photography guys". Excuse me, but prefacing your question by insulting those from you you are requesting assistance isn't very suave.
Whether there is a chemical solutions depends entirely on the nature of the ink used to print the book.
Us 'older photography guys who used chemicals' probably can't help you because the photographic printing process is based on the light-sensitive properties of silver haloids, whereas conventional printing uses inks that could be either petroleum or water based and that used colored using pigments that could be either organic or inorganic. Without knowing the actual chemical properties of the ink, there is no way to definitively answer your question.
Generically, however, I suspect that the answer is that there is no chemical process that will change the color of the ink. The only solutions would be to either photograph the map using black and white film so that everything is reduced to shades of gray, or else scan the map to produce a file that can be manipulated using Photoshop or The Gimp.
And one more thing - there are a lot of us who still use (present tense) chemicals in photography.