| 摘要 |
PURPOSE:To obtain an excellent recording/erasion characteristic by constituting a recording layer of a laminated body of an expansion layer and a holding layer, containing two kinds of dyestuffs in both these layers, and adjusting the content of these pigments and thickness of the recording layer. CONSTITUTION:A floppy disk and a tape for erasable optical information recording consist of a transparent high polymer film (a) and a recording layer (b) formed thereon. This layer (b) is constituted of a laminated body of an expansion layer (c) deformed by heating which follows laser light irradiation, and a holding layer (d). Also, the layer (c) and the layer (d) are allowed to contain different near infrared absorbing pigments D1, D2 in which absorbing wavelength areas are not superposed completely. Moreover, the content of the dyestuffs D1, D2 and thickness of the layer (b) are adjusted so that a reflection factor of the layer (b) becomes at least >=10% against a near infrared ray. In such a way, in a recording medium in which it is a fundamental principle to read a variation of the reflection factor caused by formation and dissipation of a bump, an excellent recording/erasion characteristic is obtained. |
