What is the primary ingredient in most nail polish removers?

The primary ingredient in most nail polish removers is acetone because it is highly effective at dissolving the resins and pigments found in nail polish. Acetone breaks down the molecular structure of the polish, allowing it to be easily wiped away from the nail surface. This effectiveness makes acetone a popular choice for both professional salons and home use.

While other options like ethyl alcohol do have some ability to remove polish, they are not as efficient as acetone. Water does not have the properties to dissolve nail polish effectively, while vinegar, although sometimes used as a natural alternative, also lacks the potency needed to quickly and effectively remove most formulations of nail polish. Acetone's strength and quick action are the reasons it is widely regarded as the primary ingredient in nail polish removers.