| 摘要 |
<p>Thermosensitive registration material consists of a support sheet carrying a heat sensitive compsn. comprising (a) a first system capable of producing a colour and (b) a second system developing a colour using a precursor (I) and a co-reactive substance (II). (I) is thermally decomposed into a chromogenic cpd. which can then react with the (II) to give a colour change. This decomposition takes placed at a temp. >the temp. at which the system (a) produces a colour. Pref. the chromogenic cpd. in system (a) contains a lactone ring and is esp. a phthalide or a fluorane, esp. 3,3-bis(1-ethyl-2-methylindol)-3-yl) phthalide, etc. The prods. are useful heat-sensitive copying materials which can be used to give two-colour copies, the colour depending on the temp. used. The system gives a more distinct colour change than prior art two colour systems.</p> |
