Patent ID: 7642036
Filing Date: 2010-01-05
Classification: C07D,C09B,G11B,Y10S

Abstract:
1. A method comprising recording on an optical recording medium with a laser at a wavelength of from 633 to 680 nm, wherein the optical recording medium comprises a grooved substrate, a reflecting layer, a recording layer, and an optional protection layer, wherein the recording layer comprises an azo-metal chelate dye comprising an azo dye compound and a metal, wherein the azo-metal chelate dye has a OD 2 /OD 1 value of greater than 1.25, which is measured by the following method: (1) after adding 20 mg of azo-metal chelate dye into 2 g of an octafluoropentanol (OFP) solvent, supersonic dispersion is performed at temperatures between 50° C. and 65° C. for 60 minutes to obtain a solution A, and the solution A is then cooled to room temperature (25±5° C.) to obtain a solution B; (2) the solution B is applied onto a polycarbonate substrate by spin coating at a rotating speed of 800 rpm, and the substrate onto which the elution B has been spin coated is then annealed at 80° C. for 5 minutes, the substrate thus obtained, onto which the solution B has been spin coated, being referred to as a coated substrate A; (3) the absorption spectrum of the coated substrate A is measured in a range of 400 to 800 nm; and (4) concerning the absorption peaks seen in a range of 500 to 700 nm in the obtained absorption spectrum, the absorption peak at which the optical density is the greatest and the absorption peak at which the optical density is the second greatest are selected, the optical density at the peak on the long wavelength side is defined as OD wherein the azo dye compound is represented by the following formula (1): (where R