Heyho, which type of plastic is best/worst for food containers. I’m thinking toxic substances.
Depends on the substance.
@ThantiK 's comment fills me with doubt, but before he made me think the problem described some intricate surface in N space, filled with local minimas and maximas, I was going to say PLA should be fine - it’s made from corn.
I’ve heard claims that PLA can leach toxic substances, although I can’t find proof of that with easy google searches, so I make no claims that way. But when this question comes up people make a good point: The plastic you use is not the only possible source of toxic substances.
Your plastic will be passing through a number of metal tubes and nozzles while molten and may be picking things up from there, including (if your nozzle is brass) lead.
So if you’re thinking 3D printing there’s more to consider than just the plastic you’re using. I can’t say what degree of danger that possible lead source presents… but personally any lead danger is more than I really want to deal with.
I print toys for my kids in natural PLA. They are still young so toys sometimes end up in their mouth.
Natural being un-dyed, so clearish
Nothing printed through an FFM/FDM process is going to be food safe. The surface will be pitted on a microscopic scale, which will make it impossible to properly clean even if there are no toxicity issues. It’ll make it bacteria-tastic.
This thread on RepRap talkeda bout it a lot, with some great research: http://forums.reprap.org/read.php?1,164077,176062
I wouldn’t print anything that gets into contact with food or might end up in a child’s mouth. Many aluminum parts contain lead and the filament might be contaminated with who-knows-what since it’s not meant to be food safe.
@Thomas_Sanladerer This…I get asked about food safety all the time. In the end, it doesn’t matter HOW pure and clean and safe the filament is, it matters how it got printed on your machine. And that’s not something anybody has any knowledge of other than you.
The polymers in PLA plastics are derived from corn. However, all plastics have different additives in them. Two plastics made from the same polymer can have drastically different properties because of the additives. I would not recommend putting food or liquids in any 3D printed containers unless you know for sure that it is a food safe plastic. Even then you still run into the issues @Miles_Wilford mentioned.
You can get pure polypropylene filament. Its pain to print, but PP does not react easily.
Thanks, that is a very useful thread