- 1). Soak the cloth with rubbing alcohol.
- 2). Rub the cloth over the ink that is embedded in the plastic. Rub until the ink softens and begins to transfer to the cloth. If the ink is very old and does not soften, lay the cloth over the ink stain and let it sit for at least one hour.
- 3). Dip a scrubbing brush into the rubbing alcohol and scrub it over the stain, until it is gone -- or until you have removed as much of it as possible.
- 4). Mix one teaspoon of liquid dish soap with one teaspoon white vinegar, if the stain is still visible.
- 5). Scrub the solution into the stain with the scrubbing brush. Work until you remove all of it.
- 6). Rinse the area with clear water and let it dry completely.
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