Abstract: The present invention relates to an information medium comprising an undercoat layer and a colorant receiving layer in this order on a substrate, wherein at least a part of the periphery of the undercoat layer is coated with the colorant receiving layer. Preferably, at least a part of the outer periphery of the undercoat layer is coated with the colorant receiving layer. Preferably, at least a part of the inner periphery of the undercoat layer is coated with the colorant receiving layer. Preferably, the whole of the outer and inner peripheries of the undercoat layer is coated with the colorant receiving layer.

Abstract: A signal output method for reducing jitter and forming pits having stable shapes on an optical information recording medium with high recording density is provided. A write signal includes a write permission signal including a repetition of write enable and pause intervals, and a write data signal outputted during the write enable interval. The write signal satisfies the formula Tfmax−Tfmin≧0.01T, where Tfmax is an output interval of a first write data signal among write data signals corresponding to a write permission signal immediately subsequent to a pause interval when the pause interval of the write signal is a maximum, Tfmin is an output interval of a first write data signal among write data signals corresponding to a write permission signal immediately subsequent to a pause interval of the write signal when the pause interval of the write signal is a minimum, and T is a reference period.

Abstract: Disclosed is a method for producing an information-recording medium comprising, on a substrate, a dye recording layer capable of recording information, the method comprising the step of drying the substrate formed with the dye recording layer by allowing clean air to flow while rotating the substrate at a high speed; wherein an intake for introducing the clean air is narrowed by arranging a lid having a circular opening at a central portion, at an opening disposed at an upper portion of an apparatus for rotating the substrate at the high speed.

Abstract: The present invention provides an optical information recording medium including a substrate with an on-groove and an in-groove, having successively disposed thereon a dye recording layer and a transparent sheet, wherein a width of the on-groove ranges from 50 to 140 nm, and a barrier layer is formed between the recording layer and the transparent sheet. The invention also provides an optical information recording method including irradiating the optical information recording medium with laser light from the side of the medium provided with a cover layer to form a void at a signal pit portion in the dye recording layer and thereby carrying out recording of information as well as an optical information recording medium on which information has been recorded by the method.

Abstract: An optical information recording medium of the present invention is structured by a disk-shaped transparent substrate in which a center hole is formed in a central portion thereof, a light reflecting layer, a dye recording layer containing an organic dye, an intermediate layer, an adhesive layer, and a thin protective layer. The light reflecting layer, the dye recording layer, and the intermediate layer are provided on a region of the transparent substrate at which a pre-groove is formed. The thin protective layer is provided on the intermediate layer via the adhesive layer which is formed of a photocurable resin which is cured by light of a wavelength other than a main absorption band of a recording layer dye.

Abstract: Two substrates are simultaneously produced by an injection molding apparatus, and the injection-molded substrates are alternately arranged and cooled by a cooling apparatus. The cooling apparatus has a feed screw mechanism for feeding the alternately arranged substrates in one direction while cooling air is being applied to the substrates. An information recording medium which includes a substrate is manufactured on a production line having a single injection molding apparatus for simultaneously injection-molding two substrates and four dye solution coating machines for forming a dye recording layer for recording information on each of the substrates.

Abstract: The invention provides an optical information recording medium comprising a substrate, an optional reflective layer, a recording layer, a barrier layer, an adhesive layer, and a cover layer in this order. In the first embodiment, the barrier layer covers the surface and the outer and/or inner peripheral end edge surfaces of the recording layer, the inner and/or outer peripheral portions of the substrate and the cover layer adheres to each other in at least partial region thereof via the adhesive layer, and the maximum length of this region in the radial direction is 0.4 mm or more. In the second embodiment, outer and/or inner peripheral end edge portions of the reflective layer extend past the corresponding peripheral end edge portion or portions of the recording layer, and the barrier layer adheres to the reflective layer's extended peripheral edge region.

Abstract: An optical information recording method of recording information on an optical information recording medium by irradiation of laser beam, the method comprises the steps of: forming a recording waveform which forms a first pit having a shortest pit length, by using a top pulse having a width narrower than a width of a channel clock cycle; forming a recording waveform which forms a second pit that is second shortest following the first pit, by using the top pulse and a terminal pulse having a width narrower than the width of the channel clock cycle; and forming a recording waveform which forms a pit that is longer than the second pit, by using the top pulse, the terminal pulse, and at least one multipulse formed between the top pulse and the terminal pulse. According to the method described above, pits having stable shape can be formed and thus jitter of reproduced signals can be reduced in an optical information recording medium having a narrow track pitch and high recording density.

Abstract: A disk-shaped optical information recording medium comprising a recording layer, a pressure sensitive adhesive layer or an adhesive layer, and a cover sheet in this order on a substrate, and having a central hole, a track pitch of 300 to 600 nm and a groove depth of 40 to 150 nm, for recording and playing back information by being irradiated with a laser light at a wavelength of 500 nm or less, wherein the substrate and the cover sheet are closely adhered via the pressure sensitive adhesive layer or the adhesive layer at a region including a portion of an inner circumference vicinity and an outer circumference vicinity, and the maximum value for the radial length of the closer adhesion region is at least 0.4 mm.

Abstract: An information recording medium is disclosed, comprising a substrate having provided thereon a recording layer capable of recording information by a laser ray, wherein the recording layer contains a dye compound represented by formula (I-1): wherein R1, R2, R3 and R4 each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group or a substituted or unsubstituted heterocyclic group, L1, L2 and L3 each independently represents a methine group which may have a substituent, m represents 0, 1, 2 or 3, Xk+ represents a cation and k represents an integer of from 1 to 10, provided that when m is 2 or 3, the plurality of L2 and L3 groups may be the same or different. Also disclosed is an information recording method using the above-described information recording medium.

Abstract: An optical information recording medium including a substrate having a groove that has a track pitch of 200 to 400 nm and a depth of 10 to 150 nm, the substrate having successively disposed thereon a light-reflective layer, a recording layer and a cover layer, wherein information is recordable and reproducible by irradiating a laser beam having a wavelength of 500 nm or less from a side of the medium disposed with the cover layer, and the light-reflective layer contains aluminum or an aluminum alloy.

Abstract: The present invention provides an optical data recording medium excellent in recording sensitivity and recording property (jitter). On a transparent substrate, in which a pre-groove having a depth of 20 to 100 nm is formed, a dye recording layer is formed to have a thickness at a groove portion of 50 to 160 nm and a thickness at a land portion of at least 80% of the thickness at the groove portion.

Abstract: The invention relates to a light guide film that can take in sunlight or the like for easy guidance of the light to any desired site. The light guide film comprises a flexible transparent film 1 that is provided with entrance means 2 on one side of a part 11 of its longitudinal portion and exit means 2 on one side of other part 12. An intermediate portion 13 between the parts 11 and 12 remains smooth on both sides. Light introduced from the entrance means 2 of the part 11 into the transparent film 1 is guided via the intermediate portion 13 to the exit means 2 of the part 12, from which the light is emitted.

Abstract: An optical information recording medium production process including a laminated body production step, and any of the following co-adhesion steps: a co-adhesion step including maintaining an inner peripheral face of the cover sheet so as to be at an outer side relative to an inner peripheral face of the substrate, and sticking together the cover sheet and the laminated body; a co-adhesion step including regulating a position of co-adhering using an outer peripheral face of the substrate, and sticking together; a co-adhesion step including placing the cover sheet on a flat table, and sticking together; and a co-adhesion step including, after sticking a cover sheet provided with a release sheet on the laminated body, releasing the release sheet, starting from a protruding portion of the release sheet. Also disclosed is an optical information recording medium produced by any of these processes.

Abstract: The present invention relates to a disc-shaped optical recording medium, which includes at least one sputter layer formed through a sputtering method, having an arrangement in which the inner circumference of the above-mentioned sputter layer is located on the inner side from a stack ring, and to an optical recording medium which is formed by bonding a pair of disc-shaped substrates, each having a hole in the center portion thereof, to each other through a bonding layer made from an adhesive with a print layer being formed on one side. The inner edges of the above-mentioned bonding layer and print layer are located within a range from 18 mm from the center of the above-mentioned hole.

Abstract: A surface plasmon optical modulator element includes a dielectric material block disposed so that light-to-be-modulated travels through the interior of the dielectric material block and impinges upon one surface thereof at an angle of total reflection, a metal film formed on the surface of the dielectric material block, a photo-functional film which is formed on the metal film and whose refractive index is changed upon exposure to light, and a modulating light source which projects modulating light onto the photo-functional film. The photo-functional film is formed of dye which contains an electron donor and an electron acceptor so that a photoelectron can be transferred therebetween.

Abstract: A recordable digital video disc preferably employable for information recording method using a laser beam having a wavelength of 600-700 nm, composed of a transparent disc substrate provided with a spiral pregroove, a recording dye layer placed in the pregroove, and a light-reflecting layer, arranged in order, wherein the recording dye layer has a thickness in the range of 40% to 90% of a thickness corresponding to an optical path which gives the first minimum reflectance, the optical path giving the first minimum reflectance being determined from a reflectance curve which is prepared using recordable digital video discs composed of the same disc substrate, the same recording dye layer having varying thickness, and the same light-reflecting layer.

Abstract: An optical data storage medium comprises a substrate having thereon concavities and convexities so that diffraction of reflected light is caused; a reflective layer having a high regular reflectance; and a colored region which is provided by applying transparent coloring ink to the reflective layer so that the regular reflectance of the reflective layer on the side opposite to the substrate side falls within a range of from 3 to 80%. The external appearance of the optical data storage medium provides a visual effect utilizing metallic gloss and light-diffraction-based iridescent reflection characteristics which result from the reflective layer provided on the substrate having concavities and convexities.

Abstract: An optical information recording disc showing good recording characteristics is prepared by the steps of coating a dye solution of a laser light-sensitive dye in a fluorinated cyclic alkane or alkene on a transparent substrate disc and drying the coated dye solution. The fluorinated cyclic alkane or alkene can be employed in combination with other organic solvents.

Abstract: An optical information recording medium comprising a substrate having thereon a recording layer capable of information recording by laser irradiation, wherein said recording layer contains a dye compound represented by the following formula (I), (II) or (III): R11R12N+═L11—L12═L13—NHR13.(1/m)(X1)m−  (I) R21R22N—L21═L22—L23═NR23  (II) R31R32N+═L32═L33—NR33R34.(1/n)(X3)n−  (III). The meanings of the symbols are defined and explained in the specification. Also discussed is a method for recording information using the optical information recording medium.