Isopropyl alcohol (IPA) is great for rinsing parts and cleaning liquid resin. Learn how to buy, handle, and dispose of IPA before printing. Keep plenty on hand to satisfy your printing needs. IPA is a chemical and should be handled with safety in mind.
- Rinsing parts: use Form Wash - or the rinse tub and squeeze bottle included with the Form Finish Kit - to wash liquid resin off your completed parts.
- Cleaning resin spills: IPA dissolves liquid resin and can be used to clean spills. To avoid damage, before using IPA or other cleaning agents, spot test the cleaner on a small, discreet area of the affected surface.
When cleaning polycarbonate or acrylic surfaces, such as the amber cover on the Form 2 (polycarbonate) or Form 1/1+ (acrylic), do not use IPA or ammonia-based cleaners, which can crack and damage these materials. Instead, use a special plastic cleaner such as Novus 1: Plastic Clean & Shine.
Isopropyl alcohol (also referred to in chemistry as isopropanol or 2-propanol) may be known by different names depending on your location. In the USA, it can be called “rubbing alcohol”, while in the UK it's known as “surgical spirits”. We recommend buying 90% IPA from your local pharmacy or online. Higher concentrations of IPA are available, but are much more hazardous to manage, while 90% solutions are safe for household use.
Always consult the safety data sheet (SDS) from the IPA supplier as the primary source of information. Handle IPA with gloves in a well-ventilated area. Keep away from heat, sparks, and open flame. IPA evaporates rapidly, so keep the rinse tub and bottles closed whenever possible.
When using Form Wash, use the included siphon pump to transfer liquid to and from the bucket to avoid overfilling or spilling IPA. Operate Form Wash on a clean and level surface. Always remove the wash bucket or empty alcohol from the wash bucket before storing or transporting Form Wash. Use the hydrometer, included with each Form Wash, to measure the resin concentration of IPA and know when to replace the IPA in the wash bucket. Practice safety when using Formlabs products, including Form Wash.
Recycling or Disposing of Used IPA
After some time, the IPA in your rinse tub will become more concentrated with resin; this decreases its efficacy in rinsing new parts. Replace used IPA and use fresh IPA for the best finished part quality.
For proper use, handling, and storage of solvents, obtain and observe the supplier’s separate SDS for IPA. For handling Formlabs materials, reference the SDS provided by Formlabs. Combinations of resin and IPA should be handled according to the restrictions of both. For questions, consult the appropriate SDS(s).
For large volumes of IPA, consider using a solvent recycling system, which offers a cost effective and more environmentally responsible alternative to paying for waste solvent disposal services. Solvent recycling systems utilize distillation and fractionation processes to remove solutes from waste solvents, returning the solvent to its original, functional, and pure state. Recycling IPA eliminates waste disposal costs, reduces emissions that are required to produce solvents, and lowers the cost of purchasing IPA.
IPA is flammable and should be used and stored away from sources of ignition.
Store small quantities of used IPA by keeping it in appropriately-labeled and sealed containers. Consider pouring used IPA back into an empty IPA bottle using a funnel.
For printing operations without access to solvent recycling system, note that safe and appropriate disposal methods of used IPA will vary by location:
- Check the IPA’s safety data sheet (SDS).
- Research your local government's approved methods of disposal.
- Inform your waste disposal service that your bottle contains IPA with small amounts of methacrylated monomers and oligomers (unpolymerized plastic resin) and trace amounts of photoinitiator. Have a copy of the resin's SDS on hand in case the attendant needs more information.