methylene chloride hexane several grams of highly pure meab were obtained no impurities were detectable by nmr m p 122 124 u00b0 c nmr ir and mass spectra were consistent with the proposed structure michler 39 s ketone also tetramethyl michler 39 s ketone or tmmk tetraethyl michler 39 s ketone also 4 4 u2032 bis diethylamino benzophenone or temk and meab were tested in curing hexanediol diacrylate compositions the composition included 1 isopropylthioxanthone 2 ethyl 4 n n dimethylaminobenzoate 4 benzophenone 1 aminobenzophenone compound and the balance hexanediol diacrylate the composition was applied as a 0 15 inch film to a substrate and cured with a fusion uv systems u201c h u201d bulb with 600 watts inch power with a belt speed of 55 feet per minute meab and tmmk both required 10 passes under the lamp to obtain a well cured hard polymer and temk required 25 passes this illustrates that meab and tmmk have approximately the same activity and both are much superior to the tetraethyl compound michler 39 s ketone tmmk is listed by the national toxicology program as u201c reasonably anticipated to be a carcinogen u201d based on the results of cancer studies in rats and mice seventh annual report on carcinogens u s dept health human services p 259 1994 based on comparisons of mutagenicity studies with animal cancer studies mutagens are more likely to cause cancer to produce tumors in multiple organs and to affect multiple species gold l s et al mutat res 286 75 100 1993 mutagenicity can be measured by a variety of assays the most commonly used method is the salmonella mammalian.