Three commercially available conversion varnish coating "systems" (stain, sealer, and topcoat) were selected for an initial scoping study. Total volatile content of the catalyzed varnishes, as determined by EPA Method 24, ranged from 64 to 73percent (w/w). Uncombined (free) formaldehyde concentrations, determined by a sodium sulfite titration method, ranged from 0.15 to 0.58 percent (w/w) of the resin. Each resin was also analyzed by gas chromatography/mass spectrometry (EPA Method 311) to identify the volatile components that may be emitted. The primary volatile organic constituents identified in the resin formulations included 2-butanone, n-butanol, 4-methyl-2-pentanone, toluene, ethylbenzene, 1,2,4-trimethylbenzene, and the xylenes.
展开▼
