Abstract: A system and method for replicating magnetic patterns on hard disk media includes a mask located over or above a magnetic recording layer. The recording layer may include a single, dual, or multi-layer recording layer. A pattern is or has been formed in the mask, where the pattern defines the recordable regions and the non-recordable regions to be created in one or more layers within the recording layer. Portions of the recording layer are then exposed. An etch may then be performed to create grooves within one or more layers in the exposed regions of the recording layer. The magnetic properties of at least one layer in the exposed portions of the recording layer are then altered in order to create recordable or non-recordable regions. The mask is then removed from the recording layer.

Abstract: A film which is a single polymer film and has a smaller phase difference as the wavelength becomes shorter. This film is made from an olefin-based polymer which has an alicyclic group in the side chain, such as hydrogenated polystyrene, the amount of the alicyclic group in the side chain being 60 to 90 wt % based on the whole polymer, and satisfies the following expression: R(450)/R(550)<1 wherein R(450) and R(550) are phase differences on the film plane at a wavelength of 450 nm and a wavelength of 550 nm, respectively.

Abstract: An optical recording medium in which deposition of impurities or damage to a surface of the medium illuminated by the light for signal recording and/or reproduction is to be prevented from occurring. An amine salt compound of perfluoropolyether having terminal carboxylic groups, represented by the chemical formulas (1) and/or (2): Rf—COO?N+HR1R2R3??(formula 1) R1R2R3N+H?CO—Rf—COO?N+HR1R2R3??(formula 2) where Rf denotes a perfluoropolyether group and R1, R2 and R3 denote hydrogen or a hydrocarbon group, is held on the surface side illuminated by light.

Abstract: An information recording medium having such a recording material layer on a substrate where reversible phase change between electrically or optically detectable states can be caused by electric energy or electromagnetic energy. The recording material forming the recording layer is either a material having a crystal structure including lattice defects in one phase of the reversible phase change or a material having a complex phase composed of a crystal portion including a lattice defect in one phase of the reversible phase change and an amorphous portion. Both portions contain a common element. A part of the lattice defects are filled with an element other than the element constituting the crystal structure. The recording medium having a recording thin film exhibits little variation of the recording and reproduction characteristics even after repetition of recording and reproduction, excellent weatherability, strong resistance against composition variation, and easily controllable characteristics.

Abstract: The invention provides an optical recording medium having excellent weatherability and a process for producing the same. The optical recording medium is provided with an organic dye layer, a reflecting layer and a protective layer in this order on a light-transmittable substrate. The organic dye layer contains an organic solvent in an amount of 2% to 15% by weight based on the organic dye. A solution, prepared by dissolving an organic dye in an organic solvent, is applied onto the light-transmittable substrate by a spin coating method to form an organic dye layer. A reflecting layer is formed on the organic dye layer without performing a drying treatment of the organic solvent in the organic dye layer, followed by forming the protective layer on the reflecting layer. The result is an optical recording medium containing an organic solvent in an organic dye layer in an amount of 2% to 15% by weight based on an organic dye.

Abstract: An optical polycarbonate resin molding material comprising pellets formed from a polycarbonate resin, wherein the pellets satisfy the following properties (1) and (2): (1) an average of surface areas (hereinafter referred to as “cross sectional areas”) in cutting cross sections of the pellets is 3.0 to 6.5 mm2, and a standard deviation thereof is not larger than 0.65 mm2, and (2) an average of ratios of long diameters to short diameters (hereinafter referred to as “long diameter/short diameter”) in the cutting cross sections of the pellets is 1.3 to 1.7, and a standard deviation thereof is 0.08 to 0.15, and an optical disc substrate formed from the material. According to the present invention, when the aromatic polycarbonate resin pellets which satisfy the properties (1) and (2) are used for molding, an optical disc substrate which hardly undergoes occurrence of silver streaks can be obtained, and operations at the time of molding can be facilitated.

Abstract: A method of increasing the performance of a composite lubricant material when utilized as a thin film lubricant, comprising: (a) providing a substrate including a surface; (b) providing a composite lubricant comprising a mixture of at least one perfluoropolyether compound and at least one phosphite or phosphate compound; (c) applying a thin layer of the composite lubricant to the substrate surface; and (d) treating the thin layer of composite lubricant with UV radiation at a dosage and for an interval sufficient to reduce the surface tension, increase the corrosion resistance, increase the durability and reduce the stiction/friction of the thin layer of composite lubricant.

Abstract: An optical disc-producing sheet 1, which has an adhesive layer 11 having a specific heat capacity after curing of not more than 1.9 J/g·° C. at 80° C. and a protective sheet 12, is laminated onto an information recording layer 3 (a laminate of a reflecting layer 31, a dielectric layer 32, a phase change layer 33 and a dielectric layer 32′) formed on an optical recording medium substrate 2. According to this optical disc, recorded information can be reproduced accurately even in the case that recording/erasure or reproduction of information has been carried out repeatedly.

Abstract: Disclosed are a photopolymerizable composition and a recording material containing the composition. The composition comprises a polymerizable compound having an ethylenic unsaturated bond, a compound of the following general formula (1), and a radical generator that interacts with the compound of formula (1) to generate a radical.

Abstract: A thermoplastic polymer mixture comprising at least on thermoplastic polycarbonate polymer, and at least one mold release agent including at least one polyol component, is described. At least one polyol component (I) of the mold release agent consists of a parent substance with at least 4 carbon atoms, at least 3 hydroxyl groups, at least one hydroxyl group esterified with an aliphatic carboxylic acid, and at least one free hydroxyl group.

Abstract: A method for manufacturing a bonded optical disc includes the steps of coating a solution on a substrate, heating the coated solution and the substrate to thereby form a recording layer on the substrate, and adhering a dummy substrate to the recording layer, wherein the dummy substrate is also heated.

Abstract: The invention is a magneto-optical recording medium characterized by containing at least a soft magnetic layer, a protective layer, a resin layer having a servo pattern formed thereon, a reflecting film, a lower dielectric material film, a recording film, an upper dielectric material film, and a cover layer, formed on a substrate in this order.

Abstract: An optical information medium comprises a supporting substrate 20, an information recording surface 4 on the supporting substrate 20 and a light-transmitting layer 2 on the information recording surface 4. Recording light and/or reproducing light are incident on the information recording surface 4 through the light-transmitting layer 2. The light-transmitting layer 2 comprises a light-transmitting sheet 201 formed of a resin such as polycarbonate, cyclic polyolefin and polyarylate and an adhesive layer 202 for bonding the light-transmitting sheet 201 to an associated side of the supporting substrate.

Abstract: A ridgy resin film made of a resin is formed. On a flat substrate, a first concave and a second concave are formed such as to be spaced a given distance apart from each other. Then, a resin liquid is supplied onto a land being part of the substrate exposed between the first and second concaves. Due to its surface tension, the resin liquid supplied onto the land bulges, and a ridgy resin film even in width is formed by curing the resin liquid in this state. Along the edges of the openings of the first concave and the second concave, ridges are formed. Since the resin liquid is supplied onto the land between the ridges, it does not drip nor overflow.

Abstract: A multilayered optical disk having n recording layers is designed in such a manner that the transmittance Ti of the ith layer from a light-incident side satisfies the relationship: ∏ i - l j - i ⁢ T i 2 ≥ n - j + l n when the light is focused on a recording film of the jth layer. By doing so, the recording/reading property of a multilayered medium is improved.

Abstract: The present invention is directed to-carrying out a high density magnetic recording to a material having a large coercive force by perpendicular magnetic recording head.

Abstract: The surface of a disk medium includes a substrate whose surface includes grooves and lands. A non-magnetic underlayer and a magnetic recording layer are formed on the substrate. Smoothing non-magnetic film fills the grooves, which are covered with the non-magnetic underlayer and the magnetic recording layer, so that the height of the magnetic recording layer above the grooves may reach the same level as the height of the magnetic recording layer above the lands.

Abstract: A system and method are disclosed for monitoring characteristics of a rotating substrate. As the substrate rotates in an environment, an incident light beam is emitted onto the substrate near an axis about which the substrate rotates. The emission of the incident beam is controlled as a function of the angular orientation of the substrate, so that the incident beam selectively interrogates a central region of the substrate to facilitate measuring and/or inspecting characteristics of the substrate.

Abstract: A silver-based alloy thin film is provided for the highly reflective or semi-reflective layer of optical discs. Alloy additions to silver include gold, palladium, copper, rhodium, ruthenium, osmium, iridium, and platinum. These alloys have moderate to high reflectivity and reasonable corrosion resistance in the ambient environment.

Abstract: A substract for use in a data storage system is disclosed. The substrate includes at least one core layer comprising at least one plastic or plastic composite material exhibiting a modulus of about 350 kpsi or greater, and damping agents, reinforcing agents, or combinations thereof. The damping agents, reinforcing agents, or combinations thereof, are substantially uniformly distributed within the plastic or plastic composite material. Optionally, one or more skin layers are disposed adjacent the at least one core layer.

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: An information recording medium of the present invention includes a first substrate, a second substrate disposed so as to be opposed to the first substrate, a first information layer disposed between the first substrate and the second substrate, a second information layer disposed between the first information layer and the second substrate, and an intermediate layer disposed between the first information layer and the second information layer. The first information layer includes a first recording layer that is transformed in phase reversibly between a crystal phase and an amorphous phase with a laser beam, and the second information layer includes a second recording layer that is transformed in phase reversibly between a crystal phase and an amorphous phase. The first recording layer contains, Ge, Sn, Sb, and Te, and has a thickness of 9 nm or less.

Abstract: A process for producing a fluoroalkanol of high purity containing little evaporation residue, which can be industrially easily carried out with high selectivity, is provided. In the process, a radial initiator and CF2═CFR3 (formula 3) are continuously added to CHR1R2—OH (Formula 2) to react them to form H—(CFR3CF2)n—CR1R2—OH (formula 1). In the formulae, n is an integer of from 1 to 4, each of R1 and R2 is a hydrogen atom or a C1-3 alkyl group, and R3 is a fluorine atom or a C1-4 perfluoroalkyl group.

Abstract: Methods for forming data storage media and the media formed thereby are disclosed herein. In one embodiment, the method for forming a data storage media, comprises: injection molding a substrate comprising surface features, wherein said surface features have greater than about 90% of a surface feature replication of an original master; and disposing a data layer over at least one surface of said substrate; wherein said data storage media has an axial displacement peak of less than about 500&mgr; under shock or vibration excitation.

Abstract: An information recording medium includes a first information layer and a second information layer. The first information layer includes a first recording layer in which a reversible phase change is caused between a crystalline phase and an amorphous phase by irradiation of a laser beam or application of current. The second information layer includes a second recording layer in which a reversible phase change is caused between a crystalline phase and an amorphous phase by the irradiation of the laser beam or the application of the current. The first recording layer is made of a first material, the second recording layer is made of a second material, and the first material is different from the second material.

Abstract: A method of manufacturing a magnetic recording medium, comprises steps of providing a non-magnetic substrate for a magnetic medium, the substrate including at least one major surface having a contact start/stop (CSS) or landing zone and a data zone; and forming a pattern of recesses in the substrate surface in said CSS or landing zone by embossing utilizing a stamper having a surface including a negative image pattern of said pattern of recesses. Embodiments of the invention include magnetic media comprising a non-magnetic substrate including at least one major surface having a contact start/stop (CSS) or landing zone and a data zone, said substrate surface in said CSS or landing zone comprising an embossed pattern of recesses. In addition, the data zone of the substrate surface may include an embossed servo pattern formed simultaneously with the embossed pattern of recesses formed in the landing zone.

Abstract: A recording medium for information signals including a substrate, a signal recording layer provided on one major surface of the substrate and a clamp member having a positioning unit at its center portion and formed of a material that can be magnetically attracted by a magnet. The clamp member is unified to the center portion of the substrate so that the surface of the clamp member will be flush with the substrate surface.

Abstract: A perpendicular magnetic recording media with a patterned soft magnetic underlayer is disclosed. The recording media may be a disk including a substrate, a patterned underlayer, and a magnetically hard recording layer. The underlayer may be provided in the form of concentric bands having widths less than the track widths of the recording layer. The patterned underlayer reduces or eliminates adjacent track interference.

Abstract: An optical recording medium (10) is adapted such that information is recorded by forming recording marks on a recording layer (12) that covers grooves (16) of an optical transparent substrate (14). In the recording layer (16), contiguously defined along a feed direction S of irradiation are virtual recording cells (40) which have a given unit length in the feed direction S of irradiation along the groove 16 and a given unit width in the direction orthogonal thereto. In addition, the groove width W is set so that 0.20×(&lgr;/NA)<W<0.50×(&lgr;/NA), where &lgr; is the wavelength of a laser beam to be irradiated with and NA is the numerical aperture of the objective lens for the laser beam in a irradiation optical system. The irradiation time is set in five stages or more to radiate the laser beam, thereby making it possible to record information in multi-levels.

Abstract: An information recording medium that is excellent in repeated-rewriting performance and is deteriorated less in crystallization sensitivity with time is provided, with respect to which high density recording can be carried out. A method of manufacturing the same also is provided. The information recording medium includes a substrate and a recording layer disposed above the substrate. The recording layer contains, as constituent elements, Ge, Sb, Te, Sn, and at least one element M selected from Ag, Al, Cr, Mn, and N and is transformed in phase reversibly between a crystal phase and an amorphous phase by an irradiation of an energy beam.

Abstract: A composite sheet including a paper layer made of a wood pulp having a Canadian standard freeness value of 350 to 500 ml and a transmittance of at least 7% for a light with a wavelength of 940 to 960 nm, a transparency improving layer provided over one side of the paper layer so that said paper layer overlaid with said transparency improving layer exhibits a transmittance of at least 11% for a light with a wavelength of 940 to 960 nm, and a release liner provided over an opposite surface of the transparency improving layer from the paper layer. A thermosensitive recording adhesive label sheet has the above composite sheet and a thermosensitive recording sheet provided on the composite sheet through an adhesive layer.

Abstract: The present invention relates to a multi-layered disc-shaped information recording medium having a plurality of signal recording layers each carrying information signals. In preparing the recording medium, a first substrate obtained on punching a sheet obtained in turn by having a signal recording pattern transcribed on it from a first stamper and by forming a semi-transparent film on a signal surface is bonded to a second substrate obtained on injection molding a synthetic resin material. The second substrate is prepared by having transcribed to it a signal recording pattern formed on a second stamper provided on an injection molding device. A reflective film is formed on a signal surface having the transcribed second substrate. The first and second substrates are bonded together on their signal recording layers by a transparent adherent layer.

Abstract: A magnetic data recording medium substrate has a contact zone and a data zone. The contact zone is textured by forming multiple texturing features, each having a bell-shaped profile resembling a Gaussian curve. The features preferably are formed by pulsed laser energy applied to a glass substrate, or to an aluminum nickel-phosphorous substrate coated with a glass layer. As compared to previous laser texturing approaches, the laser beam is less narrowly focused to provide a beam impingement area with a diameter of at least three microns, forming texturing features with diameters of at least three microns. The texturing features preferably are uniform in height and diameter, and may be symmetrical or have asymmetrical aspects, so long as bell-shaped profiles are present in the direction of travel of the recording medium, relative to transducing heads.

Abstract: An optical information recording medium includes a first information layer, a separating layer, a second information layer and a protective substrate in this order on a transparent substrate. The second information layer comprises an optical interference layer, a lower protective layer, a recording layer, an upper protective layer, and a reflective layer in this order from the side near the transparent substrate. The reflective layer has a refractive index of at least 2.5 at a wavelength &lgr; of light beams. The second information layer is a reflectance-increase type where the reflectance with respect to the light beams incident from the transparent substrate side after recording is higher than that before recording. It is possible not to provide the optical interference layer if the ratio n1/n2 of the refractive index n1 at the wavelength &lgr; of the recording layer before recording to the refractive index n2 thereof after recording is not more than 0.8.

Abstract: In a magneto-optical disc contained in a cartridge, a first dielectric layer, signal recording layer, second dielectric layer, and light reflecting layer are sequentially stacked on a substrate having formed grooves, and a first protective layer, print layer using at least one color and second protective layer are sequentially stacked on the light reflecting layer. Thickness of the second protective layer is not smaller than that of the print layer, and thickness of the first protective layer is not smaller than 2 &mgr;m. Thus the recording medium having the print layer on at least one surface maintains a sufficient resistance to corrosion and a good slidableness.

Abstract: An optical disc includes a substrate, and a recording layer and transparent layer formed in this order on the substrate. A light is incident from the transparent layer to write and/or read an information signal. The substrate comprises a first resin layer forming a surface of the substrate on which the recording layer is formed, and a second resin layer having a higher flexural modulus is formed on the first resin layer.

Abstract: A laminated disc composed of at least two supporting discs superposed upon another, each of the supporting discs having a thickness of 0.01 to 1 mm and being made of a vinyl alicyclic hydrocarbon polymer. This laminated disc is used as an optical disc including digital video disc (DVD).

Abstract: An optical disk, which comprises: a common integral substrate having grooves and/or pits formed on its both sides: and a film structure on at least one side of the integral substrate. They are manufactured by preparing two stampers; simultaneously forming grooves and pits on both sides of an integral substrate by use of said two stampers mounted on a respective fixed mold and moving mold; and forming the film structure on at least one side of said integral substrate by depositing material from targets suspended to both sides of said integral substrate. The disks are superior in mechanical properties and reliability. As for reliability, the present optical disk is prepared without using a bonding process, which overcomes the problem of adhesive out-flow.

Abstract: Provided is a method for manufacturing a glass substrate for an information recording medium, which is advantageous in that oozing of an alkali and deformation of a texture are suppressed. The glass substrate is chemically reinforced, and a texture is formed in the glass substrate, and then treated with a neutral or alkaline aqueous solution. In the texture forming step, the surface of the glass substrate is etched in a depth of 0.5 to 10 nm.

Abstract: A machine readable medium containing a data structure for processing color data for a three-dimensional object, the data structure comprising separating color data of a full color three-dimensional object in a pre-processing module into data of three primary colors; using the data of three primary colors to create data for separate shell objects of the three primary colors; and transferring the color data and the data for separate shell objects to a solid imaging printer.

Abstract: It is possible to obtain a disk substrate in which an edge of a center hole is free of flash. The disk substrate (23) in which the center hole (24) is provided with a straight portion (24a) and a tapered portion (24b), and an edge on the side of a signal transfer surface (22) of the tapered portion (24b) is provided with an R surface or C surface (24c), a mold apparatus optimum for molding the disk substrate (23), and a disk taking-out apparatus.

Abstract: Disclosed is a process for preparation of crystallized glass obtained by making a glass containing TiO2 subjected to a phase separation step and a crystallization step, where the phase separation step has heat treatment of the glass at a temperature in a range from a temperature of the glass transition temperature Tg (Tg−30° C.) to a temperature 60° C. higher than the glass transition temperature Tg (Tg+60° C.). There are also disclosed a crystallized glass for information recording disk composed of the crystallized glass obtained by the preparation process, where a mean particle size of the crystal particles is in a range of equal to or less than 100 nm, or where a transparency at a wavelength of 600 nm is 40% or higher; and an information recording disk, composed of the glass, having a polished surface with a surface roughness Ra (JIS B0601) in a range from 0.1 to 0.5 nm.

Abstract: An optical recording medium is designed to generate a read signal free from waveform distortion during reproduction of information. The optical recording medium is formed with information tracks on which data pits carrying information data is to be formed, and prepit tracks previously formed with a plurality of prepits. Each of the information tracks and each of the prepit tracks are positioned adjacent to each other, and each of the prepits is formed to be spaced apart from adjacent information tracks in at least its bottom part.

Abstract: A glass substrate for use as an information recording medium has an average surface roughness (Ra) in the range of 0.3 nm≦Ra<3.0 nm and includes surface irregularities shaped and distributed isotropically and arranged substantially in succession. The surface irregularities include 5 to 50,000 convexities having a height of at least 3 nm and no convexities having a height of at least 15 nm within an area of 50 &mgr;m×50 &mgr;m. A porous region produced by an acid treatment process in the glass substrate would be completely removed if excessively etched by an alkaline solution. However, the etching process using the alkaline solution can be stopped at a stage where the pores in the porous region are enlarged by controlling conditions for the acid and alkali treatment processes.

Abstract: A magnetic recording medium comprising a card-type disk drive and a magnetic disk cartridge. The card-type disk drive is loaded in a card slot of electronic equipment. The magnetic disk cartridge has a magnetic disk rotatably supported within a housing, and is inserted into and ejected from the disk drive through a cartridge-inserting slot. The magnetic disk cartridge includes an ejection manipulation member that has a push manipulation portion and a leading end portion. The leading end portion protrudes from the front wall of the housing when the push manipulation portion is pushed in a cartridge-inserting direction. The disk drive has cartridge ejection means for moving the magnetic disk cartridge in a cartridge-ejecting direction when the leading end portion of the ejection manipulation member protrudes from the front wall of the housing.

Abstract: A substrate for an information recording medium has a microwaviness average height Ra′ not greater than 0.05 microinch as measured by a contactless laser interference technique for measurement points within a measurement region of 50 &mgr;m□-4 mm□ on a surface of the substrate.

Abstract: The invention relates to a method of producing a matrix suitable for use in a plastic element-producing machine, a matrix produced in accordance with the method and the use of such a matrix to form a plastic element. One side of the matrix (2) is provided with a negative microstructure (2a) which is replicated in plastic material (3) to form a positive microstructure (3a) on a plastic element (3), wherewith the matrix (2) can be produced by applying a layer of material (7) to the positive microstructure side of a master. The positive microstructure side of the master has a thin wear-resistant layer (7) which serves as a first wear surface, wherewith said layer will present irregularities (7a) which correspond essentially to the microstructure, and wherein at least said irregularities are filled-in with a plastic composite (8′) so as to form a carrier element (8) for supporting the first wear layer (7). The layer (7) can further be provided with means for supplying heat energy to said matrix.

Abstract: The optical disk medium permits an increase in recording density using a complex refractive index variation of an inorganic oxide film in a super-resolution medium using an inorganic oxide film. The reflectance of the disk increases due to the complex refractive index variation of the inorganic oxide film. Specifically, in the case where the inorganic oxide film is an oxide film comprising Co, a reflect addition film is provided. The effective spot diameter used for read-out is reduced, thereby increasing recording density. By using a material for which the complex refractive index varies sharply, the recording density can be approximately doubled.

Abstract: The present invention relates to use of transition metal complexes in photochromic devices, to the production of optical information storage devices based on a polymeric matrix and on metal oxides with adsorbed transition metal complexes, to the production of photochromic materials constituted by a film of metal oxide with adsorbed two different type of molecular systems, one acting as a charge transfer sensitizer and the second as an electron acceptor.

Abstract: A method of forming a crystalline, phase-change layer that remains atomically smooth on its surface. Also, an atomically smooth, crystalline, phase-change layer made according to this method. The method can include forming a phase-change layer over a substrate, forming a thick capping layer over the phase-change layer, changing the phase-change layer from an amorphous phase to a crystalline phase, removing the thick capping layer, and forming a thin capping layer over the phase-change layer.