| 摘要 |
<p>The fluoran compounds of the formula (I) are new red color forming chromogenic dyes. <IMAGE> (I) wherein R represents an isobutyl or isopentyl group, R1 represents a hydrogen or halogen atom or an alkyl group, R2 represents a hydrogen or halogen atom or an alkyl group, R3 represents a hydrogen atom, and R4 represents a hydrogen atom, or R4 and R1 as well as R2 and R3 taken together with the carbon atoms to which they are attached may form a benzene ring which may be substituted with a halogen atom. They are used, together with an acidic developer, in chromogenic recording materials for use in pressure sensitive copying paper, heat-sensitive recording paper and thermo-sensitive, reversible color changing composition.</p> |
