Methyl acetate: uses and what to specify
Technical article · Eapearl Chemical ·
Methyl acetate is a fast-evaporating ester solvent used where a formulation has to dry quickly, dissolve resins well and stay inside a tightening VOC budget. In practice it is bought as a replacement for acetone and MEK — same speed, different regulatory position.
What it is
Methyl acetate is the methyl ester of acetic acid: a clear, mobile liquid with a mild fruity odour, fully at home in the group of low-molecular-weight esters that formulators reach for when drying time matters. It is miscible with the common organic solvents — alcohols, ketones, other esters, aromatic and chlorinated hydrocarbons — and, unlike most esters used at this speed, it takes up a useful amount of water.
| CAS number | 79-20-9 |
|---|---|
| Molecular formula | C3H6O2 |
| Molecular weight | 74.08 g/mol |
| Also sold as | Methyl ethanoate · acetic acid methyl ester · MA |
| PubChem CID | 6584 |
Grade-dependent values — assay, water content, acidity, colour — belong on the certificate of analysis for the batch you receive, not in an article. We publish them per grade, not as a typical figure.
What methyl acetate is used for
Coatings, inks and printing
This is the largest use by volume. Methyl acetate sits at the fast end of the evaporation scale, which is where a formulator goes for tack-free time, for a clean release on a printing press, and for the open-time control that decides whether a film levels or orange-peels. In nitrocellulose, acrylic and cellulose acetate butyrate systems it is an active solvent rather than a diluent: it does the dissolving, so it can carry a higher resin load.
Adhesives and sealants
In solvent-borne contact adhesives the solvent has two jobs — hold the polymer in solution and then leave fast enough to give a usable open time. Methyl acetate is chosen when the assembly cannot wait and when the substrate will not tolerate the slower aromatics.
Cleaning, degreasing and paint removal
Good solvency for resins and oils plus quick evaporation makes methyl acetate a natural fit for wipe cleaning and equipment flushing, where a residue is the failure mode. It also appears in formulated paint and varnish removers, usually in place of a chlorinated solvent that the customer no longer wants on the label.
Extraction and chemical synthesis
As a reaction and extraction medium it is used where a low-boiling ester is wanted — notably in decaffeination and in flavour and fragrance work, and as an acetylating building block in synthesis.
Personal care and household formulations
Nail products and fast-drying consumer formulations use it for the same reason industry does: it leaves quickly and it has a mild odour compared with the ketones it replaces.
The reason formulators switch to it
Methyl acetate’s commercial position comes from regulation, not from chemistry. In the United States the EPA lists it among the compounds excluded from the definition of a volatile organic compound under 40 CFR 51.100(s), on the basis of negligible photochemical reactivity — the same treatment given to acetone. In practice that lets a formulator cut the regulated VOC figure of a coating without slowing it down.
The European position is different and this is where offers get compared wrongly. EU rules define a VOC by physical property — the Paints Directive 2004/42/EC uses an initial boiling point of 250 °C or below — so a low-boiling ester such as methyl acetate counts towards the VOC content of a product placed on the EU market. A solvent that is VOC-exempt in Ohio is not VOC-exempt in Bavaria.
What to do with that: confirm which definition applies in the market where the finished product is sold, before you reformulate around the exemption. We will not tell you the switch is compliant for your market; we will ship the grade and the documents that let your regulatory team decide.
How it compares with the solvents it usually replaces
Directional comparison — the ranking holds, the exact figures belong on each product’s data sheet.
| vs acetone | Comparable evaporation speed and a similar regulatory position in the US. Methyl acetate has the milder odour and a less aggressive effect on many plastics; acetone is cheaper and more widely stocked. |
|---|---|
| vs MEK (2-butanone) | Methyl acetate evaporates faster and is not classed as a VOC in the US, where MEK is. MEK dissolves a wider range of resins — the substitution is not automatic and has to be tested on the actual system. |
| vs ethyl acetate | Methyl acetate is the faster of the two and tolerates more water. Ethyl acetate is the softer solvent, is easier to source in food and pharmaceutical grade, and is often preferred where the odour profile matters. |
| vs methylene chloride | Used as a replacement in paint removers by customers moving away from chlorinated solvents. Methyl acetate is flammable, which methylene chloride is not — the fire protection assumptions of the plant change with the substitution. |
Hazard classification and what it means on the floor
Methyl acetate carries an EU harmonised classification, so the hazard statements are not a supplier’s opinion. As published on our product page, the classification is Danger, with:
- H225 — highly flammable liquid and vapour;
- H319 — causes serious eye irritation;
- H336 — may cause drowsiness or dizziness;
- EUH066 — repeated exposure may cause skin dryness or cracking.
Source: European Chemicals Agency, Index No. 607-021-00-X, Table 3 of Annex VI to Regulation (EC) No 1272/2008 (CLP), 23rd ATP, harmonised list as of 2026-07-07.
Three practical consequences. The vapour is heavier than air and will sit in pits and sumps, so the extraction point goes low, not high. H336 is a central-nervous-system effect and it is the statement behind ventilation and exposure monitoring in confined work, not the flammability. EUH066 is why operators who wipe with it develop cracked hands within weeks unless gloves are part of the procedure.
What to specify when you order
An inquiry that can be priced in one message states these:
- Assay and the impurity that matters to you — usually water and free acid. Both shift with storage, so the specification is agreed against the certificate of analysis, not against a catalogue value.
- Grade — industrial, or a tighter specification if the material goes into a registered formulation.
- Packaging — drums, IBC totes or ISO tank; see logistics and packaging for the formats we hold.
- Destination and end use — a flammable liquid ships under transport rules that the destination port and the receiving plant both have to accept.
Storage and handling in one paragraph
Store cool, away from ignition sources and oxidising agents, in a bonded and earthed container, in a ventilated area. Esters hydrolyse slowly in the presence of water and acid, so a drum left open gains water, gains acidity and drifts out of specification — the same material can fail on assay six months after passing on arrival. Where a plant draws from one drum over a long period, we recommend smaller packs rather than a single large one.
Questions we actually get asked
Is methyl acetate the same as ethyl acetate?
No. They are different substances with different CAS numbers and different behaviour: methyl acetate is the faster-evaporating of the two and takes up more water. They are not interchangeable without testing.
Is it a VOC?
It depends on the market. Excluded from the US EPA definition of VOC under 40 CFR 51.100(s); counted as a VOC under EU rules, which define VOCs by boiling point. Check the definition that applies where your finished product is sold.
Can it replace acetone directly?
Often, but not blindly. The evaporation behaviour is comparable and the regulatory position in the US is similar, yet solvency for a specific resin and compatibility with a specific plastic substrate differ. Trial the substitution on the actual formulation.
What packaging is it supplied in?
Drums, IBC totes and ISO tank containers for bulk. The format for a specific grade is stated on the product page and confirmed with the quotation.
Why does the article not give a boiling point or flash point?
Because the number that matters to you is the one on the certificate of analysis for the batch you receive, and because a supplier publishing textbook constants as if they were its own measurement is the reason so many data sheets disagree with each other. Ask us for the safety data sheet and the specification for the grade you are considering — both are free and both are specific.