Abstract: An optical recording medium 300, which is provided with multiple recording layers formed on a transparent substrate to improve a recording characteristic, includes two recording layers (a first recording layer 302 and a second recording layer 305) provided on a transparent first substrate 301 and capable of recording and reading information by use of an irradiated laser beam 310, and an intermediate layer 304 provided between the two recording layers. A predetermined groove serving as a recording track is formed on a surface on an opposite side to the first substrate 301 side in terms of the intermediate layer 304. The intermediate layer 304 is formed of multiple resin layers (a first resin layer 304a, a second resin layer 304b, . . . , and an outermost resin layer 304c).

Abstract: A dual-layer optical recording medium, which is formed by adhering a disk substrate (inverted-stack structure) formed by stacking a reflective layer (1) and a recording layer (1) on a substrate (1) and a disk substrate (conventional-stack structure) formed by sequentially stacking a recording layer (2) and a reflective layer (2) on a transparent substrate (2) with a transparent resin layer interposed therebetween, is prepared such that the transparent resin layer has a product obtained by multiplying the thickness by the elastic modulus at 25±5° C. falling within the range of not less than 2.0×104 MPa·?m to not more than 30.0×104 MPa·?m, resulting in suppressing excessive deformation involving an adjacent track portion produced by recording optical information in the recording layer (1) of the inverted-stack structure, thereby reducing crosstalk and providing satisfactory recording and/or reading characteristics in high-speed recording applications.

Abstract: In an optical recording medium having two recording layers of a first recording layer and a second recording layer, the second recording layer contains metallized azo dyes represented by the following general formula (I) or (II), and recording characteristics of the second recording layer are improved by having optical density of 1.3 times as large as, or 1.3 times greater than, that of a dye contained in the first recording layer. (In this regard, rings A1 and A2 are nitrogen-containing heteroaromatic rings, rings B1 and B2 are aromatic rings, and X is alkyl group substituted by at least two fluorine atoms.

Abstract: In a single-sided incident type optical recording medium having a plurality of dye containing recording layers, sufficient reflectance and excellent recording characteristics necessary to record or read information in or from a dye containing recording layer positioning farther from a side from which a light beam comes in can be obtained. The optical recording medium has a first substrate (21) having a guide groove, a first dye containing recording layer (22), a semitransparent reflective layer (23), an intermediate layer (24), a second dye containing recording layer (25), a reflective layer (26) and a second substrate (27) having a guide groove. Information is recorded or read in or from the first dye containing recording layer (22) and the second dye containing recording layer (25) by irradiating the light beam from the first substrate's side. The depth of the guide groove on the second substrate is within a range from 1/100×? to ?×? where ? represents the recording/reading wavelength.