I made some coasters using different colors of TPU filament, including some with fluorescent yellow. I had a bottle of olive oil sitting on one of the coasters on the counter next to my stove. I was cleaning and discovered that the oil bottle had some dribbles going down the side and ultimately into the coaster (that’s why I used a coaster). When I moved the coaster to wipe the counter top, I found that the oil had leached some of the fluorescent dye out of the TPU filament onto the counter top.
It’s probably not a good idea to have fluorescent filaments in contact with food, especially if the food is oily.
Agree. Also, the nature of FDM printing creates little crevices for bacteria to thrive regardless of material. If you want to 3D print things for use around food then go resin printing. It won’t solve the “what chemical is near my food” problem, but it would eliminate the tiny crevices (aka layer lines).
OP’s issue seems to be entirely orthogonal to food, it doesn’t make sense for this thread to continue in that direction, it’s been rehashed elsewhere in other threads, go there instead if you want to continue and have a discussion about it with people interested in arguing the subject.
OP discovered solvents can leach the dye out of his filament, that’s it, full stop. He didn’t say that his filament was in contact with food that was going to be consumed, it was food that was spilled on the counter.
If he is actually saying “don’t make food handling things out of special filament XYZ” (which I trust he isn’t, because that would be absurd, you don’t make food handling things out of ANY filament unless they are certified safe) then this thread should be merged with the others and he can be eviscerated there.
This is perhaps a great segue into the [stated] reasoning behind PLA pure [not an ad, but lol]
The PLA is fairly well understood in how it behaves. The additives/colorants are the ones that need vetting, since every mfr is kinda free to just put in whatever soluble, poisonous, radioactive, or heavy metal stuff they need to shove in to create that color/opacity. Youre kidding yourself if you think there’s any regulations or periodic testing.
I wonder if it was just the oil that caused the leach or a combination with the hot environment near the stove? At least at my house that area does get more than warm. If you get curious you could make a science project of it and try different cooking oils, even plain water and test in areas away from the stove. And maybe test a coaster with nothing on it near the stove to see if it leaches without interacting with another substance.
People make gaskets and plugs (from TPU), some associated with gasoline and shoes which come in contact with who knows what from the outside or things like lotions from the inside so it seems like it is normally pretty stable stuff (I know there are different hardnesses) so it makes me think any issue probably comes back to the dye itself.