| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a novel croconium dye useful as an image-forming material, an infrared heat-sensitive recording material, an optical recording element, an optical film material or the like. <P>SOLUTION: The compound is represented by general formula (I) (wherein R<SP>11</SP>is a proton-bearing substituent having a pKa value of 18 or lower; R<SP>12</SP>is a hydrogen atom, an aliphatic group, an aromatic group or a heterocyclic group; the total number of atoms other than hydrogen atoms in R<SP>11</SP>and R<SP>12</SP>is at least 11; R<SP>13</SP>is a substituent; n13 is an integer of 0-4; when n13 is 2 or more, a plurality of R<SP>13</SP>'s are the same or different and may be linked together to form a ring). <P>COPYRIGHT: (C)2007,JPO&INPIT |
