Patent ID: 7672217

Claim:
An optical recording medium comprising at least: a supporting substrate; a recording layer on the supporting substrate, the recording layer comprising at least one organic compound as a major component; a dielectric layer on the recording layer; and a light-transmitting layer on the dielectric layer, the light-transmitting layer having a thickness of 1 to 150 μm and being capable of transmitting laser light with a wavelength of 390 to 420 nm for recording and reproducing information, wherein the at least one organic compound in the recording layer includes at least one monomethine cyanine dye that has the minimum value n min of its refractive index n (real part of the complex refractive index) within the range of 370 to 425 nm and has a refractive index n of 1.2 or lower with respect to the wavelength of the recording/reproducing laser light, and the organic compound, when absorbing the laser light, melts or degrades to bring about a change in the refractive index, thereby effecting recording of the information, and wherein the monomethine cyanine dye contains a monomethine group with two nitrogen-containing heterocyclic rings positioned on ends of the monomethine group, said two nitrogen-containing heterocyclic rings being selected from the group consisting of a combination of indolenine and indolenine, a combination of benzothiazole and benzothiazole, and a combination of benzothiazole and quinoline.