I've never tried it for ink, although I've gotten tons of other stains out this way.
Boil water in your kettle. Lay the fabric over a bowl or sink. Then holding the kettle up high over the fabric, SLOWLY pour water onto it (watch you don't splash yourself). By pouring slowly from up high, the water hits the fabric harder and seems to literally knock out the stain. This even worked on a dark wine stain in carpeting.
As the others have said, try a scrap first to see if it does the job.
Best of luck.