| 摘要 |
<p>96A chromene compound which contains a skeletonrepresented by the following formula (1) and has high color 5 optical density at the time of exposure, double peakcharacteristic, little initial coloration, a practicalfading speed and durability. R1(wherein R1 is an electron donor group having a Hammett10 constant of less than 0, the ring including X is a hetero ring formed together with the 7-position and 8-position carbon atoms, and X is an oxygen atom, sulfur atom or group represented by .NR2 directly bonded to the 7-position carbon atom.)No Figure</p> |
