Abstract: An optical recording medium comprising a recording and a metal reflective layers on a transparent substrate having a groove, wherein the recording layer comprises an azaporphyrin metal complex dye with 1 to 4 meso-nitrogen atoms as a main component; recording and/or reproduction can be conducted using laser beams with wavelengths of &lgr;1 and &lgr;2 which is shorter than &lgr;1; a refractive index n of the recording layer is 2.0 or more at &lgr;1 and 1.8 or more at &lgr;2 as well as an attenuation coefficient k of the layer is 0.04 to 0.20 at &lgr;1 and 0.30 or less at &lgr;2; and the groove has a pitch of 0.70 to 0.85 &mgr;m, a half-value width of 0.20 to 0.

Abstract: A recordable optical recording medium comprising a recording layer containing an organic dye which can absorb a laser beam and a metal reflective layer directly or via another layer on a transparent supporting substrate having a pre-groove and a pre-pit, wherein the organic dye has a refractive index nk of 2.

Abstract: An optical recording medium comprising at least a recording layer and a reflecting layer on a substrate wherein the recording layer contains at least one dipyrromethene-metal chelate compound represented by general formula (1): wherein R1 to R6 independently represent hydrogen, halogen, nitro, cyano, hydroxyl, amino, carboxyl, sulfo, substituted or unsubstituted alkyl with up to 20 carbon atoms, alkoxy, alkylthio, aryloxy, arylthio, alkenyl, acyl, alkoxycarbonyl, carbamoyl, acylamino, aralkyl, aryl or heteroaryl; R7 represents halogen, aryl, heteroaryl, alkoxy, alkylthio, aryloxy or arylthio; A represents substituted or unsubstituted aromatic or heterocyclic ring with up to 20 carbon atoms; L1 represents substituted or unsubstituted bivalent residue forming a ring together with carbon atoms to which it attaches and optionally containing a hetero atom; and M1 represents transition metal element.

Abstract: In an optical recording medium, a recording layer is formed by coating a substrate with a solution of coloring matter comprising a coloring matter dissolved in a solvent comprising a mixture of cyclooctane and at least one hydrocarbon having 6 to 9 carbon atoms other than cyclooctane. The obtained optical recording medium enables suppressing the leakage of land prepit signal for address information into RF signal for recorded data at the time of recorded data reproduction, thereby attaining a lowering of error rate.

Abstract: An optical recording medium comprising a recording and a metal reflective layers on a transparent substrate having a groove, wherein the recording layer comprises an azaporphyrin metal complex dye with 1 to 4 meso-nitrogen atoms as a main component; recording and/or reproduction can be conducted using laser beams with wavelengths of &lgr;1 and &lgr;2 which is shorter than &lgr;1; a refractive index n of the recording layer is 2.0 or more at &lgr;1 and 1.8 or more at &lgr;2 as well as an attenuation coefficient k of the layer is 0.04 to 0.20 at &lgr;1 and 0.30 or less at &lgr;2; and the groove has a pitch of 0.70 to 0.85 &mgr;m, a half-value width of 0.20 to 0.

Abstract: An optical recording medium comprising at least a recording layer and a reflecting layer on a substrate wherein the recording layer contains at least one dipyrromethene-metal chelate compound represented by general formula (1): 1

Abstract: An optical information recording medium is here disclosed which comprises a transparent substrate, a recording layer comprising an organic dyestuff on which information can be written by a laser beam, a reflective layer and a protective layer formed in this order on the substrate, the aforesaid optical information recording medium being characterized by containing a pit.multidot.edge control agent for the formation of recording pits, particularly a dyestuff thermal decomposition accelerator in the recording layer. By the addition of the pit.multidot.edge control agent, deviation properties and jitter properties can be remarkably improved, whereby a CD-R medium having a low error rate and good recording properties can be provided. In consequence, stable compatibility with a commercial CD player can be secured.

Abstract: In an audio sound recording/reproducing apparatus, instruction information related to a document is recorded in a recording region of a semiconductor memory together with the document. In the semiconductor memory, flags related to a document portion and an instruction portion, and the addresses of the document and the instruction portions are provided. At the time of reproduction, the instruction portion is reproduced prior to reproduction of the document portion. When the content of the semiconductor memory is stored in a built-in memory in the apparatus, the instruction portion is stored before the document portion is stored. Since the instruction portion is reproduced prior to the document portion at the time of reproduction, the user does not have to retrieve the instruction portion.

Abstract: An optical information recording medium is here disclosed which comprises a transparent substrate, a recording layer comprising an organic dyestuff on which information can be written by a laser beam, a reflective layer and a protective layer formed in this order on the substrate, the aforesaid optical information recording medium being characterized by containing a pit.edge control agent for the formation of recording pits, particularly a dyestuff thermal decomposition accelerator in the recording layer. By the addition of the pit.edge control agent, deviation properties and jitter properties can be remarkably improved, whereby a CD-R medium having a low error rate and good recording properties can be provided. In consequence, stable compatibility with a commercial CD player can be secured.

Abstract: An optical recording medium for pit length recording with excellent error rate and jitter value which has a transparent injection molded resin substrate, a recording layer containing a phthalocyanine dye of formula (1) overlying the substrate and a covering layer overlying the recording layer. Also, a method of optical recording by pit length recording with a focused laser beam using an optical recording medium as described above.

Abstract: An optical recording medium of a single plate type capable of recording comprises a transparent resin substrate having a groove of 900-1800 .ANG. in depth and 0.3-0.6 .mu.m in width, a recording layer containing a dye overlying the substrate, a reflective layer overlying the recording layer and a protective layer overlying the reflective layer, the thickness of the recording layer being 800-1250 .ANG. at the groove portion and 500-1100 .ANG. at the land portion.

Abstract: An optical recording medium of a single plate type comprises a substrate having a groove, a recording layer containing a dye overlying the substrate, a reflective layer overlying the recording layer and a protective layer overlying the reflective layer, wherein the recording layer is formed by a spin-coating method and the dimension of the groove varies from the center portion of the substrate toward the outer periphery thereof.

Abstract: An optical recording medium of a single plate type comprises a substrate, a recording layer overlying the substrate, a reflective layer overlying the recording layer, and a protective layer overlying the reflective layer, the recording layer being produced by coating a nonpolar solvent-soluble substituted phthalocyanine dye in a nonpolar solvent and the nonpolar solvent content of in the recording layer being 5% by weight or less.

Abstract: Disclosed are optical recording media, each of which is composed of a substrate and a recording layer formed on the substrate. The recording layer includes an organic-dye-containing layer and an organopolysiloxane resin layer formed by the condensation of a trifunctional silane represented by R.sup.1 Si(OR.sup.2).sub.3-n (X).sub.n and a tetrafunctional silane represented by Si(OR.sup.3).sub.4-m (X).sub.m, wherein R.sup.1, R.sup.2 and R.sup.3 individually represent an alkyl or aryl group, X a hydroxyl group or a halogen atom, and n and m 0, 1, 2 or 3 and 0, 1, 2, 3 or 4, respectively.

Abstract: Disclosed are optical recording media, each of which is composed of a substrate and a recording layer formed on the substrate. The recording layer includes an organic-dye-containing layer and an organopolysiloxane resin layer formed by the condensation of a trifunctional silane represented by R.sup.1 Si(Or.sup.2).sub.3-n (X).sub.n and a tetrafunctional silane represented by Si(OR.sup.3).sub.4-m (X).sub.m, wherein R.sup.1, R.sup.2 and R.sup.3 individually represent an alkyl or aryl group, X a hydroxyl group or a halogen atom, and n and m 0, 1, 2 or 3 and 0, 1, 2, 3 or 4, respectively.

Abstract: An optical recording medium comprising practically a naphthalocyanine dye represented by the following general formula (I): ##STR1## wherein M means a metal, metal oxide or metal halide, and --OR.sub.1, --OR.sub.2, --OR.sub.3 and --OR.sub.4 are the same or different and denote ether groups respectively having R.sub.1, R.sub.2, R.sub.3 and R.sub.4 each of which is a saturated or unsaturated hydrocarbon group having 4-12 carbon atoms.

Abstract: An optical recording medium comprising practically a naphthalocyanine dye represented by the following general formula (I): ##STR1## wherein M means a metal, metal oxide or metal halide, and --OR.sub.1, --OR.sub.2, --OR.sub.3 and --OR.sub.4 are the same or different and denote ether groups respectively having R.sub.1, R.sub.2, R.sub.3 and R.sub.4 each of which is a saturated or unsaturated hydrocarbon group having 4-12 carbon atoms.