| 摘要 |
Disclosed are normally substantially colorless chromogenic oxime ether of Michler's hydrol color precursor compounds having the following generic structural formula: <IMAGE> wherein R1 and R2 each represents an organic radical. More specifically, R1 may represent either a lower alkyl group having from one to five carbon atoms or a phenyl group and R2 may represent a substituted or unsubstituted phenyl group having the following formula: <IMAGE> wherein R3 and R4 each separately represents either a hydrogen atom, a chlorine atom or a nitro group. These compounds are initially substantially colorless and are capable of becoming highly colored when brought into reactive contact with many conventional Lewis acid materials or the like. Accordingly, these compounds are highly useful as a component of pressuresensitive copying papers. |
