| 摘要 |
PURPOSE:To widen the selection of dyestuff and to increase the size of the film layer of a recording layer by forming a dyestuff film by using a superfine particle dispersion of dyestuff to form a recording layer and considering the solubility of the dyestuff in a solvent. CONSTITUTION:The recording disk 1 is a contact type optical recording disk which can make the reproduction corresponding to the standards specified for CDs by bringing a reflection layer into tight contact with the surface of the recording layer. The optical recording disk 1 has the recording layer 3 essentially consisting of the dyestuff on the surface of the substrate 1 and has the reflection layer 4 and protective film 5 in tight contact with the recording layer 3. This substrate 2 is a disk-shaped substrate and is formed by using a resin or glass transparent to recording light and reproducing light in order to enable recording and reproducing from the back surface side of the substrate 2. Spiral continuous grooves for tracking are provided on the recording layer 3 forming surface. The fluctuation width of the reflectivity of the unrecorded part of the dyestuff film is <=5 to 100 of the reflectivity and the max. grain size (r) of the particles exhibit a relation r<=alpha<#1 with the film thickness (d) of the dyestuff film and the reproducing wavelength lambda. |
