IPA vs Acetone vs MDC: Choosing an Industrial Cleaning Solvent

Ask three plants what they clean with and you will get three answers. All of them may be right, because IPA, acetone and MDC are not interchangeable products competing on price. They are different tools, and the correct one depends on what you are removing and what you are removing it from.

Quick comparison

IPA, the safe default for precision cleaning

Isopropyl alcohol is the solvent to reach for when the surface matters more than the soil. It removes light oils, flux residue, fingerprints and process dust, dries without leaving a film, and is gentle on most plastics, elastomers and coated surfaces.

It is the standard choice for electronics assembly, optical and lens work, and equipment sanitising, where 99 percent and 70 percent grades serve quite different purposes. What IPA will not do is shift cured resin or heavy grease. Push it at a job that needs real solvency and you will simply use a great deal of it.

Acetone, the fast worker for resin and adhesive

Acetone has strong solvency and the fastest evaporation of the three. It strips uncured paint, dissolves polyester and epoxy resin, clears adhesive residue and cleans spray guns quickly, leaving effectively no residue behind.

The trade-offs are real. It is highly flammable and needs disciplined storage and earthing. It attacks polycarbonate, ABS, acrylic and many painted surfaces, so it is a poor choice near finished assemblies. Because it flashes off so quickly it can chill a surface and pull in moisture, and it will strip skin oils fast, so gloves are not optional.

MDC, when the job is heavy and fire risk is unacceptable

Methylene dichloride is the strongest cleaner of the three and the only non-flammable option, which is why it is common in paint stripping, degreasing and metal preparation where an ignition source cannot be excluded.

That strength comes with a strict handling requirement. MDC demands genuinely effective ventilation and exposure control, it is unsuitable for most plastics, and it must never be used with aluminium in confined conditions. It is a controlled-environment solvent rather than a general shop-floor one.

How to choose in practice

• Cleaning delicate assemblies, electronics or plastics then IPA, almost always.
• Removing resin, adhesive or uncured coating then acetone, with proper flammable storage.
• Degreasing metal or stripping cured coatings near ignition sources then MDC, with ventilation to match.
• Unsure about the substrate then test on a hidden area first. A ruined batch costs far more than the trial.

Do not judge on price per litre alone

The cheaper drum is not the cheaper job. A weak solvent used at three times the volume, with longer labour time and more rework, is more expensive than the correct solvent bought once. Compare cost per cleaned unit rather than cost per litre, and hold purity constant while you do it, because wet or contaminated solvent changes both the result and the consumption rate.