One of the most frequent support requests we get is a fairly straightforward question: Is Coex 3D PETG filament food safe? It's a reasonable thing to ask, PETG is a material widely used to make water bottles and other food containers.
We get this question from hobbyist printers looking to print their own water bottles or cookie cutters, and even industrial users who want to print parts that will be in an FDA-approved food safe environment.
It seems like a simple yes/no question at first glance, but the answer is a bit more complicated than that. We can start to answer it by looking at the steps that go into creating a 3D printed PETG part, from raw resin all the way to the final product. By looking at the materials and any possible impurities that may be introduced at each step, we can more thoroughly answer this question.
Is the resin food safe?
In its raw form, yes, the resin that is used to make our PETG filament is FDA-approved for use in applications where it will make contact with food. We have the documentation to prove it!
If you're about to stop reading because you think the question has been answered - just hold on! We haven't even made the resin into filament yet, nor have we added colorant - let alone created a final part with our filament.
Okay, so is the colorant food safe?
No. The colorant we use in our PETG filament (or any of our filaments) is not specifically FDA-approved for use in food-contact applications.
That said, your next thought may be, "Okay, so I'll just use natural PETG filament and it'll be fine!" - but there's still more to consider.
Is your facility and production methods considered FDA food safe?
Also no. Our facility is not inspected to FDA standards for food safety. We definitely keep the place pretty clean! But we are not held to FDA-level standards which would also require regular audits to ensure that we can call our materials safe for food contact.
So at this point, for anyone looking for official documentation that our materials are fully safe for food contact, to ensure your own compliance with standards and regulations - that is not something we are able to provide. Our materials, as we sell them, are not certified as safe for food contact.
Even if the materials were food safe, a 3D printed part might not be!
So we've got a definitive answer - Coex 3D filaments are not officially certified as food safe. But even if you do find filament that is food safe, there's still things to keep in mind when printing with it.
The most important factor when 3D printing parts for food contact is layer lines. They're an inescapable result of the FDM process. Not only do they look undesirable and are a source of mechanical weakness in parts, but bacteria love them! When food particles get into the layer lines, it makes a perfect breeding ground for bacteria and mold. Even if you throw a part into the dishwasher, it won't be enough to get rid of really nasty bugs like E. coli and salmonella.
Another consideration - is your 3D printer food safe?
Obviously, the filament has to go through your 3D printer in order to create a part, so this is another place that can introduce impurities that would make a part unsafe for contact with food.
The nozzle is the main source of possible impurities, normal brass nozzles will slowly wear out as you print with them, and anything that wears off of the nozzle ends up in your print. Brass nozzles can also contain lead, which is certainly not food safe!
Using a stainless steel nozzle is a good option for ensuring the nozzle doesn't compromise food safety of a 3D printed part. Make sure to dedicate this nozzle to only printing with food safe materials to ensure all parts made with it remain food safe.
So assuming you're using a food-safe filament, have taken the proper precautions to ensure your printing process doesn't introduce toxic contaminants in your print, and are willing to dispose of your parts after a few uses to avoid bacteria in layer lines - great! You're on your way to making food safe parts for your own kitchen.
That said, you can use 3D printing for food-related projects, without the 3D printed part itself ever touching the food!
Another option - transforming 3D prints into food safe parts
If you don't want to seek out a food-safe filament, there are still options for creating parts for your kitchen using 3D printing. 3D prints can be coated with food-safe polyurethane or epoxy resins, or used to create molds for forming food-safe materials! For example, you can use 3D printed parts as vacuum forming molds, which is a great option if you want to create custom chocolate or candy molds.
Another great use of 3D printing for the kitchen is prototyping and fit-testing. For example, if you're making a tool that you want to be especially ergonomic and comfortable to use, 3D printing is a great way to quickly prototype new designs and see how they feel. And then, once you're satisfied with your design, you can cast the part in a food safe material and create as many as you need!
While the answer to the question "Is Coex 3D PETG filament food safe?" is, strictly speaking, no, there are options to consider if you want to use 3D prints in contact with food, and important safety considerations to keep in mind. As always, if you have any further questions, don't hesitate to reach out to firstname.lastname@example.org!