My local thrift loves to price mark stuff with a black Sharpie style permanent marker pen on items with plastic or rubber surfaces. In cleaning these items up for re-sale on eBay I find that if I use the usual solvents like rubbing alcohol or Goo Gone about 95% of the marker ink comes off immediately, but there is often this distinct shadow of the original marking that remains on the plastic surface of the item no matter how much more solvent and elbow grease I employ.
Why is this? Why can’t I get ALL the marker ink up?
You could try soaking the item in whichever solution got the bulk of it off. I assume what’s happening is that your getting the surface stain off, but some of it has soaked into the porous material. Soaking it might give the solvent a chance to get down there as well and carry some of the ink out.
The easier way to do it would probably be to take a paper towel and fold it over a bunch of times, wet it with your solvent and just set it on top of the writing (or what’s left of the writing) for a little while. Rewetting as necessary.
Because you’ve removed the gunck that sits on the surface but you can’t (easily) remove the effects of gunk that has:
Etched the surface
Reacted with the surface
Also, remember that you need to try all the different types of solvent that you can think of. If isopropyl removes 95% then it may be that you need to use something completely different (petrol, detergent, turps, white spirit) to get rid of the other 5%.
I once had one of the old, beige, style keyboards that had got a bit grubby and I thought I’d tried everything to clean it. But there still remained a definite tinge of discolouration. Then I discovered that the one thing I hadn’t tried was water!!! That got rid of the last vestiges of grime.
I found in the past that, ironically, non-permanent marker is remarkably good at removing permanent marker…
Not really an answer as such to the OP’s question (removing the shadow) but try it anyway try scribbling over the permanent marker with a non-permanent, then wipe.
I found that dry erase board cleaner works to get grime off of keyboards.
Which reminds me of something else. I had a math teacher that was in a conference somewhere when the person lecturing wrote on the dry erase board with permanent marker. He said over the next few hours they tried everything they could think of to clean it off and it wouldn’t budge. By the end they were tired and getting kind of giggly and decided to try cold coffee…came right off.
Lacquer thinner is good for removing marker and other junk.
It doesn’t hurt plastic laminate used on countertops. In fact carpenters use Lacquer thinner to clean off the adhesive left behind after installing laminate. I had several sticky areas along the edge after my countertops were done. I asked my contractor and he got out the Lacquer thinner and a rag.
Always test a small area before using any solvent.
A well-known teachers’ trick, at least in schools with whiteboards (which is more and more of them, unfortunately). Whiteboard markers have solvents in them. So, if someone accidentally - or on purpose - writes on a whiteboard with a permanent marker, scribble over the permanent stuff with a proper whiteboard marker. The solvent will dissolve some of the permanent ink. Wipe away and repeat as necessary.
I imagine the success of this method on plastic will depend on how porous the plastic is.
Back when I worked retail, I made the mistake of writing how much each shelf would hold of a certain item on that shelf with washable marker, figuring I could go back later and just wipe it off, since it’s washable, right? Didn’t work. Windex ended up being what took it off.
Later on I got to wondering what else windex would take off, and sharpie marks turned out to be one of the things it would remove.
Ronsonol lighter fuel might remove it as well. It makes a great cleaner, if you’re careful with it.
The problem is related to the chemical structure of plastics and the dyes in the pen—related to what makes them “permanent” markers. The solvents that are used to keep the dye liquid in the pen and transfer to a variety of surfaces act to physically soften, then unfold the long polymer chains of the plastic. As the solvents evaporate, leaving just the pigments behind, the polymers re-fold in a new arrangement, forming an almost impenetrable lattice holding on to the pigments. Your surface cleaning got what it could reach, but it can’t make it inside the newly formed plastic itself.
But there’s actually a simple solution—the microwave, a turntable, and a glass of plain water. Basically, you want to heat the plastic so that it “unfolds” again and releases the dyes, but not so much that it merely folds in a different configuration re-trapping them. So here is what you do: put the glass of water in the center of the microwave’s turntable. That will absorb most of the microwave energy, keeping the item from getting too hot. Next, put the item on the outside edge of the turntable so that it revolves around the glass, moving in and out of the microwaves hot spots. Experiment a bit to find the right amount of time before you can take it out and clean it.
I know it sounds like a pain in the ass, but you said you needed to get *all *the marker off before selling it on Ebay. You can try other ways, but trust me: nuke it while it orbits; it’s the only way to be sure.
We tried every cleaning product in the house to get permanent marker off old plastic computers (like Commodore 64s), and the winner ended up being a paste of bicarb soda and vinegar.
try scribbling over the permanent marker with a non-permanent, then wipe.