| 摘要 |
PURPOSE:To enable a color forming composition to be used as, for instance, a pressure- sensitive copying paper or thermal recording paper for use in a near infrared region or as a photosensitive planographic plate material or a photo-resist film, by using a specified fluorene compound in the color forming composition. CONSTITUTION:A color forming composition comprises as a color reaction colorless substance a fluorene compound of formula I, wherein X is hydrogen, an alkyl, halogen, alkoxyl or the like, and each of R<1>, R<2>, R<3> and R<4> is an alkyl, cycloalkyl, benzyl or phenyl, with the proviso that R<1> and R<2>, or R<3> and R<4> may be inked to each other to form a pyrrolidino or piperidino group with the adjacent nitrogen atom. The composition, substantially colorless perse, is capable of forming a developed color image which has high absorption in a near infrared region also. Therefore, the composition can be used for a recording material, e.g., a pressure-sensitive copying paper or thermal recording paper, giving recorded images capable of being read by a reader having a reading wavelength range in a near infrared region, or as a printing-out composition for a photosensitive planographic plate material, a photo-resist film or the like having high absorption in an infrared region also. |
