If the amount of ink that spilled is more than just a few splatters (e.g. in the case of an overflowing maintenance tank), you should consider unhooking the carpet from the carpet tack strips at the nearest wall and rolling or folding it back to get to
underneath the carpet and padding. I found that even after I cleaned up the carpet surface, over time the spot came back, and it was due to capillary action from still wet ink on the padding and subfloor surface. Cut out the small section of padding that got wet, cleanup up the subfloor (isopropyl alcohol worked best for me) and make sure it is not wet, then patch it with a new piece of scrap padding of the same thickness. Then just fold your carpet back in place and stretch onto the carpet tack strips at the baseboard. A Carpet Tucker tool can help with the last part, but it's possible to do it without one.
It's best to do the above steps before doing any final cleaning on the carpet surface. For carpet spot removal, I find Folex to be one of the best:
Folex.