Abstract: A lithographic printing original plate, a lithographic printing plate using the lithographic printing original plate and a process for producing the lithographic printing plate are disclosed. The lithographic printing original plate has, on a substrate, a photosensitive layer made of a crosslinked polymer comprising a hydrophilic polymer, a crosslinking agent and a light absorbing compound or comprising a hydrophilic polymer, a crosslinking agent, a light absorbing compound and a hydrophobic polymer, and has properties that the photosensitive layer is changed from ink-repellent to ink-receptive by irradiation with a light.

Abstract: A lithographic printing original plate, a lithographic printing plate using the lithographic printing original plate and a process for producing the lithographic printing plate are disclosed. The lithographic printing original plate has, on a substrate, a photosensitive layer made of a crosslinked polymer comprising a hydrophilic polymer, a crosslinking agent and a light absorbing compound or comprising a hydrophilic polymer, a crosslinking agent, a light absorbing compound and a hydrophobic polymer, and has properties that the photosensitive layer is changed from ink-repellent to ink-receptive by irradiation with a light.

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: Provided is an optical recording medium in which per-pits in a ROM area have a depth of 250 nm or more and 350 nm or less; pre-grooves between the pre-pits have a depth of 30 nm or more and 170 nm or less; wobbling tracks have an amplitude of 25 nm or more and 110 nm or less; the product of the depth of the pre-grooves between the pits and the wobble amplitude of the track is 3100 or more; and pre-grooves in a RAM area have a depth of 130 nm or more and 250 nm or less. The optical recording medium is a hybrid disk having such good signal characteristics as satisfying the Orange Book standards.

Abstract: An optical recording medium has a recording layer, a reflective layer and a protective layer, all of which are arranged on a substrate. The recording layer contains a porphyrin compound represented by the following formula (1): ##STR1## wherein R.sub.1 to R.sub.8 independently represent a hydrogen atom, an alkyl group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylthio group or a halogen atom, R.sub.9 to R.sub.12 independently represent a hydrogen atom or an alkyl group, and X.sup.- represents an anion.

Abstract: There is provided with an optical recording medium comprising at least a dye-containing recording layer and a reflective layer laminated on a transparent substrate in this order which has a reflectance of 65% or higher, measured through the substrate, to a light beam having a selected wavelength (.lambda.1) of from 770 to 830 nm and has a reflectance of 15% or higher to a light beam having a selected wavelength (.lambda.2) of from 630 to 690 nm and which is recordable and reproducible with a laser beam having the wavelength of .lambda.1 and being reproducible with a laser beam having the wavelength of .lambda.2. In addition, the recording layer has a dye A having the absorption maximum at the wavelength shorter than 630 nm mixed with a dye B having the absorption maximum at the wavelength of from 630 to 900 nm. Alternatively, an interference layer is provided along with the recording and reflective layers.

Abstract: An optical recording medium comprising a transparent substrate; a recording layer on the transparent substrate; a metal reflective layer; and one or more protective layers. These layers are laminated successively on the transparent substrate. The outermost protective layer is formed of an ultraviolet curable resin containing an organic filler and/or an inorganic filler having water absorbency and/or oil absorbency. The protective layer has a printable surface permitting writing characters with writing instruments or ink jet printers.

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 comprises a substrate, a recording layer overlying the substrate in a manner such that it is not present at the inner and outer peripheral portions of the substrate, a metal reflective layer overlying the recording layer in a manner such that the inner periphery of the metal reflective layer is coterminous with that of the recording layer while the outer peripheral portion of the reflective layer extends over the outer perphery of the recording layer, and a protective layer wholly covering the metal reflective layer extending over the recording layer, both at the inner and outer peripheral portions. The optical recording medium exhibits an excellent adhesion strength of the protective layer even when stood under high humidity and high temperature conditions for a long period of time, and the protective layer is not peeled off when subjected to a tape peeling test.

Abstract: An optical recording medium comprises a substrate, a recording layer overlying the substrate in a manner such that it is not present at the inner and outer peripheral portions of the substrate, a metal reflective layer overlying the recording layer in a manner such that the inner periphery of the metal reflective layer is coterminous with that of the recording layer while the outer peripheral portion of the reflective layer extends over the outer periphery of the recording layer, and a protective layer wholly covering the metal reflective layer extending over the recording layer, both at the inner and outer peripheral portions. The optical recording medium exhibits an excellent adhesion strength of the protective layer even when stood under high humidity and high temperature conditions for a long period of time, and the protective layer is not peeled off when subjected to a tape peeling test.

Abstract: An optical recording medium comprises a transparent substrate, a recording layer containing at least one organic dye overlying the substrate, a metallic layer directly contacting and overlying the recording layer, a protective layer comprising at least one layer directly contacting and overlying the metal layer, a layered print portion comprising at least one layer directly contacting and overlying the protective layer, and said protective layer and said print portion satisfying the following relationship:.SIGMA.AiBi+.SIGMA.CjDj<3 (.mu.m) (1)where Ai (.mu.m) is a thickness and Bi is a curing shrinkage rate of the i-th protective layer, respectively, where i is an integer of 1 or more, Cj (.mu.m) is a thickness and Dj is a curing shrinkage rate of the j-th print portion layer, respectively, where J is an integer of 1 or more.

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 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: 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: This invention relates to an optical recording medium characterized by high sensitivity, high stability, etc, and a process for making the optical recording medium. Specifically, the present invention provides an optical recording medium composed of a transparent substrate having prepits and/or pregrooves for system control signals and first and second recording layers formed thereon in order, the both layers having individually a specific reflectance, transmittance and absorbance. To the optical recording medium, a laser beam is irradiated on the transparent substrate side to record or read out information and, by detecting the variation of the amount of light as a sum of the reflected light from the boundary between the first recording layer and the substrate and the reflected light from the boundary between the second recording layer and the air, the system control signals are primarily obtained from the prepits and/or pregrooves.

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: Disclosed herein is a fabrication process of an optical recording medium permitting writing and reading-out of signals without any reflective layer. The medium is fabricated by coating, on a transparent thermoplastic resin substrate havnig pregrooves and pits or holes for preformatting signals, a dye solution of a phthalo/naphthalocyanine dye represented by the following general formula (I): ##STR1## wherein M means a metal, metal oxide or metal halide, and L.sub.1, L.sub.2, L.sub.3 and L.sub.4 mean individually a benzene or naphthalene ring skeleton which is unsubstituted or substituted by at least one monovalent substituent --Z selected from the class consisting of the following substituents: --R.sup.1, --OR.sup.2, --SiR.sup.3 R.sup.4 R.sup.5, --SR.sup.6, --COR.sup.7, --COOR.sup.8, --COHNR.sup.9, --NR.sup.10 R.sup.11, --R.sup.12 OR.sup.13, and --R.sup.14 X wherein R.sup.1 -R.sup.14 denote individually a hydrocarbon group having from 1 to 12 carbon atoms and X stands for a halogen atom.

Abstract: Disclosed herein is an optical recording medium permitting recording and reading-out of signals without any reflective layer. The optical recording medium comprises a transparent substrate and an optical recording layer provided directly on the substrate. The recording layer contains at least 80 wt. % of a naphthalocyanine dye represented by the following general formula (I): ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 may be either the same or different and mean individually a straight-chain or branched alkyl group having 5-12 carbon atoms and M denotes a metal or a metal oxide or halide.

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.