| 摘要 |
PURPOSE:To contrive enhancement of contrast, preservation stability and rewritability, by a method wherein an optical recording medium layer comprising a thermochromic organic material capable of being reversely brought into two colored states by heating and cooling is provided on a base. CONSTITUTION:In the rewriting-type recording method, a lowly colored state obtained heating a thermochromic organic material being in a maximally colored state is used as a recorded state. For example, a 1:1 mixed powder of crystal violet lactone and phenolphthalein is placed in a Ta boat, and is heated, whereby the powder is once melted and gradually colored (blue), the color is lightened, and a thin transparent film is soon formed on an acrylic resin substrate 21 (E state). When the optical recording medium in this state is gradually heated, a recording medium layer 22 is colored in clear blue (C state). When the medium is irradiated with a 1mum diameter beam of short pulses of He-Ne laser with a wavelength of 633nm, a transparent spot form pit of 1mum in diameter is formed. When the spot part is heated and gradually cooled, the original blue color is recovered. This change can be repeatedly induced. |
