| 摘要 |
<p>Novel color-forming di- and triarylmethane compounds possessing certain S-containing ring-closing moieties, namely, a thiolactone, dithiolactone or thioether ring-closing moiety, to certain metal salts thereof and to a method of synthesizing the thiolactone compounds. In a further embodiment, this invention relates to novel recording materials and to a method of imaging and forming color by contacting these dye precursor compounds with a Lewis acid material capable of opening the thiolactone, dithiolactone or thioether ring-closing moiety whereby the compound is rendered colored, that is, converted to its chromophore color.</p> |
