BigPatents India

A recording material for a medium used for the recoring film of a write-once type information recording disk equipped with a transparent resin substrate on which concentric or spiral grooves were formed and a recording film which was formed on the grooves, characterized in that it is formed by one organic coloring matter having an anion portion and a coloring matter having an anion portion and a coloring matter portion in which the maximum absorption wavelength zone exists at a longer wavelength side than the wagvelength of short wavelength laser beam irradiated on the recording film and forms a record mark on the recording film by irradiation of the short wavelength laser beam, and the record mark has a higher optical reflection coefficient than the optical reflection coefficient of the recording film before irradiation of the short wavelength laser beam. This material realizes so-called Low to High property.