Nail Polish Remover Containing Methyl Acetate
Publication Date: 2003-Dec-19
The IP.com Prior Art Database
Methyl acetate is an alternative to ethyl acetate for use in a non-acetone nail polish remover. A new California regulation (Regulation For Reducing Volatile Organic Compound Emissions From Consumer Products, Subchapter 8.5 Consumer Products, 94509; http://www.arb.ca.gov/consprod/regs/cpreg.pdf) (hereinafter referred to as California Regulation CCR 94509) limits nail polish removers to 0% VOC (volatile organic compounds) effective December 31, 2004. Ethyl acetate is a VOC as defined under California Regulation CCR 94508; however, methyl acetate has been exempted by the U.S. EPA (40 CFR Part 51.100) and by California. In formulations that contain a large volume of water, such as nail polish remover formulations, methyl acetate is more prone to undergo hydrolysis, producing methanol and acetic acid. A buffer study was performed to determine if sodium acetate and/or sodium citrate buffers provide more stable methyl acetate formulations by slowing hydrolysis. Samples were prepared with methyl acetate, Eastman DB solvent (butoxydiglycol), and water without buffer and buffered with 0.01M and 0.02M sodium acetate and/or sodium citrate. Samples were aged at 45°C. Hydrolysis was evaluated by measuring acetic acid using gas chromatography and by monitoring the apparent pH change over time. Data indicate that both buffers are very effective at slowing hydrolysis at both 0.01M and 0.02M concentration. After 12 weeks at 45°C, non-buffered formulations have pH values ranging from 2.4 to 4.4 and as much as 16.8% acetic acid, while buffered solutions have pH values ranging from 4.4 to 5.8 and acetic acid from 0.16% to 1.07%. Thus a non-acetone, 0% VOC nail polish remover can be formulated containing methyl acetate, water, butoxydiglycol, and a buffer, such as sodium acetate or sodium citrate, to slow hydrolysis. While Eastman DB solvent was used in these examples, it is understood that other LVP-VOC (as defined by California Regulation CCR 94508) that provide miscibility for mixtures of water and methyl acetate may be used with or in the place of Eastman DB solvent.