摘要 |
PURPOSE:To obtain the titled recording medium having absorption characteristics of a wavelength in visible and near infrared regions and converting light to thermal energy upon the effective absorption of light and enabled in high density recording and optical reproduction, by containing a specific azulenium salt compound. CONSTITUTION:A compound represented by general formula [I] is obtained by mixing an azulene compound and a corresponding aldehyde compound in a strong acid medium. A photothermal conversion type recording medium is obtained, for example, by forming a thin film 2 containing an azulenium salt compound to a substrate 1. The thin film 2 is formed by the vacuum vapor deposition or coating of the azulenium salt compound and the content of the azulenium salt compound is 0.1-99wt% in the thin film 2 and the thickness of said film 2 is et to 10mum or less. A pit 5 is formed by irradiating or contacting the thin film 2 with electromagnetic radiation 4. The scanning of low output laser is applied to the pit formed part and a pit non-formed part along a track and the reflectivity difference thereof is read by a photodetector. |