What Is Methyl Acetate?
Methyl acetate, also known as methyl ethanoate or acetic acid methyl ester, is a carboxylate ester with the formula CH3COOCH3 and CAS number 79-20-9. It is a clear, colorless liquid with a sweet, fruity smell. Methyl acetate is weakly polar and lipophilic, which makes it an effective solvent for many resins, oils, and coating polymers. It is flammable and evaporates quickly, leaving little residue.
Products That Contain Methyl Acetate
Methyl acetate appears in a wide range of commercial formulations.
Industrial and automotive paints, lacquers, and varnishes
Wood stains and sealers
Industrial adhesives and glues
Paint strippers and graffiti removers
Cleaning and degreasing products
Certain printing ink formulations
Processed foods as a flavoring agent in trace amounts
Why Methyl Acetate Is Used in These Products
Formulators choose methyl acetate for three reasons. First, it dissolves a broad range of polymer binders and resins, so it works well in paints, inks, and adhesives. Second, it dries quickly, which speeds up production lines and reduces waiting time between coating layers. Third, it is a low-cost, widely available solvent that can replace more toxic oxygenated solvents in many recipes while delivering similar evaporation behavior.
Methyl Acetate vs Ethyl Acetate
Methyl acetate and ethyl acetate are close chemical relatives, but they are not interchangeable in every formula. Ethyl acetate is more common as a solvent because it is less toxic and less water-soluble. Methyl acetate dissolves in water up to about 25 percent at room temperature, and its water solubility rises sharply at elevated temperatures. In coatings and inks, the choice between the two depends on evaporation rate, solvency, and regulatory limits for the specific application.
Safety Considerations
Methyl acetate is a flammable liquid and its vapors can ignite if exposed to heat, sparks, or open flames. Handle it in well-ventilated areas, keep containers closed, and use appropriate personal protective equipment. Prolonged skin contact can cause dryness and irritation, and high vapor concentrations may irritate the eyes and respiratory tract.
Frequently Asked Questions
What products contain methyl acetate? It is found in industrial and automotive paints, lacquers and varnishes, wood stains and sealers, industrial adhesives, paint strippers and graffiti removers, cleaning and degreasing products, printing inks, and in trace amounts as a flavoring agent in processed foods.
What is the CAS number of methyl acetate? The CAS number is 79-20-9, with the formula CH3COOCH3; the compound is also known as methyl ethanoate or acetic acid methyl ester.
Is methyl acetate the same as ethyl acetate? No. They are different esters; methyl acetate dissolves in water up to about 25 percent at room temperature and is somewhat more toxic than ethyl acetate, so the two are not interchangeable in every formula.
Is methyl acetate flammable? Yes, it is a flammable liquid whose vapors can ignite if exposed to heat, sparks or open flames, so it must be handled in well-ventilated areas with containers kept closed.
Why do formulators use methyl acetate? Because it dissolves a broad range of polymer binders and resins, dries quickly to speed up production lines, and offers a low-cost alternative to more toxic oxygenated solvents in many recipes.
Can methyl acetate be used as a flavoring agent? In some jurisdictions it is permitted in processed foods only in trace amounts and must comply with local food additive regulations.