Abstract: An information recording medium comprises a substrate, a second recording layer, a second light transmitting layer, a first recording layer for recording different information from that to be recorded in the second recording layer, and a first light transmitting layer. The second recording layer is formed with a continuous second microscopic pattern of grooves. The first recording layer is formed with a continuous first microscopic pattern of grooves that is different from the second microscopic pattern. Both sidewalls of raised portions of the first and second microscopic patterns are formed with wobbling so as to be parallel with each other. Auxiliary information and a reference clock is recorded on these sidewalls alternately and continuously.

Abstract: A method for producing a concaves-convex member having a concavo-convex pattern on a surface of a base material, including: forming a covering layer on surfaces of at least concave portions of an original master for producing a concavo-convex member, with a concavo-convex pattern provided on its surface; forming a barrier layer on a surface of the covering layer positioned at the at least concave portions of the original master; forming a base material by electrodepositing metal on a surface of the original master which is provided with the covering layer and the barrier layer on the at least concave portions; and separating, from the original master, the base material provided with the barrier layer and the covering layer over surfaces of at least convex portions, wherein a metal element contained in the barrier layer has an ionization tendency smaller than that of a metal element contained in the covering layer.

Abstract: A method of minimizing distortion in a glass sheet manufacturing process wherein the stress in a parent sheet of glass is measured along each edge of the sheet. The stress data is then used to develop a distortion predictor for predicting the in-plane distortion which sub-sheets of the parent sheet are likely to exhibit when the parent sheet is cut into pre-determined sizes. The in-plane distortion may be predicted based on criteria established by the glass manufacturer, or supplied by an original equipment manufacturer (OEM).

Abstract: The optical storage medium, in particular a read-only optical disc, comprises a substrate layer, a read only data layer comprising a pit structure and being arranged on the substrate layer, a mask layer comprising nanoparticles for providing a super resolution near field effect, and a dielectric layer arranged between the data layer and the mask layer. The dielectric layer has a thickness, which changes in dependency of the pit structure and is for example a plastic layer having a completely flat surface for providing a uniform arrangement of the nanoparticles. For the manufacturing of a respective optical storage medium, the dielectric layer is arranged on the data layer advantageously by means of spin coating.

Abstract: A method for producing a glass substrate for magnetic disk, which is capable of effectively removing a crack is provided. In the method for producing a glass substrate for magnetic disk, there were provided a preparation step 1 of preparing a circular glass substrate having a main surface, a back surface opposing to the main surface, an inner side surface defining a through-hole penetrating from the main surface to the back surface and an outer side surface opposing to the inner side surface; a pre-polishing step 2A of polishing the inner side surface and the outer side surface of the glass substrate; a lapping step 3 of lapping the polished glass substrate; and a post-polishing step 2B of polishing the inner side surface and the outer side surface of the lapped glass substrate.

Abstract: According to one embodiment, there is provided a stamper holder which holds a disk-shape metal stamper for molding having a center hole with an inner diameter of 17.5 mm or less and formed with patterns of protrusions and recesses for a recording medium on a surface in a state that the stamper holder is fixed to a first die having a center hole, in which the stamper holder has an approximately cylindrical shape so as to be inserted into the center hole of the first die and comprises a flange provided at one end configured to hold an inner peripheral portion of the stamper surface near the center hole, and an outer diameter of the flange is 17.6 mm or less.

Abstract: An information recording medium (100) includes a first recording area (no-wobbling section) where control information which is clock information (Wobble) or address information (LPP) for recording or reproducing record information is not pre-formatted and a second recording area (wobbling section) where the control information is pre-formatted. In the first recording area, a part or whole of management information (FS1a) for managing recording position or the reproduction position of the recording information is pre-recorded.

Abstract: An injection-molding device includes at least first and second mould parts, defining a mould cavity, wherein at least one of the mould parts includes a heating device, for heating the mould part in the vicinity of a mould cavity surface, the heating device includes an inductive coil having a plurality of windings and being powered by an oscillator. The heating device further comprises a thin top member, which functions as a susceptor for electromagnetic energy emitted by the inductive coil, which is placed in grooves in a carrier member. An intermediate member is placed between the top member and the carrier member. The intermediate member does not function as a susceptor to any grater extent, but provides mechanical stability while allowing the heat generation to be concentrated to the top member.

Abstract: The information recording medium of the present invention is provided with a substrate and an information layer including a recording layer. Rerecording and reproducing of information are performed by irradiating the information layer with a laser beam. The recording layer contains, as its main component, a material composed of Te, O, and M, where M denotes at least one element selected from Ru, Rh, Pd, Ag, Re, Os, Ir, Pt, and Au. In the material, the content of Te atom is 1 to 19 atom %, the content of O atom is 20 to 70 atom % (preferably 40 to 70 atom %), the content of M atom is 11 to 79 atom % (preferably 11 to 59 atom %, and more preferably more than 35 atom %). The material is, for example, is indicated as the region enclosed by A, B, C, and D, preferably by C, D, E, and F, and more preferably by E, F, H, and G, in the composition diagram of a ternary material of Te—O—Pd shown in FIG. 1.

Abstract: An injection-moulding device is disclosed, comprising at least a first (1) and a second (3) mould part, defining a mould cavity (4). At least one of the mould parts comprises cooling ducts (5), for cooling the mould part in the vicinity of a mould cavity surface (11), and heating means (6), for heating the mould part in the vicinity of the mould cavity surface. The cooling ducts (16) comprise grooves, in a carrier member (17), and the heating means comprises an inductive coil (18) having a plurality of windings, wherein at least a part of the inductive coil is placed in a cooling duct groove.

Abstract: The present invention is a silver alloy including silver as the main component and at least one rare-earth element as a first dopant element, and excellent in reflectance maintenance property. In the present invention, the first dopant element is preferably samarium, neodymium, lanthanum, cerium, ytterbium, terbium, dysprosium, holmium, erbium, thulium, europium, and gadolinium. Also, in the present invention, the silver alloy preferably includes, as a second dopant element, at least one element selected from copper, manganese, silicon, chromium, nickel, cobalt, yttrium, iron, scandium, zirconium, niobium, molybdenum, tantalum, tungsten, platinum, gold, rhodium, iridium, palladium, indium, tin, lead, aluminum, calcium, gallium, bismuth, antimony, strontium, hafnium, and germanium.

Abstract: A chemically strengthened glass substrate for use as the substrate of an information recording medium such as a magnetic disk, magneto-optical disk, DVD, or MD, wherein a strengthened formed by chemical strengthening exists on the outer edge surface and on the inner edge surface but substantially not on a surface on which an information recording layer is formed.

Abstract: An information recording medium comprises a substrate, a second recording layer, a second light transmitting layer, a first recording layer for recording different information from that to be recorded in the second recording layer, and a first light transmitting layer. The second recording layer is formed with a continuous second microscopic pattern of grooves. The first recording layer is formed with a continuous first microscopic pattern of grooves that is different from the second microscopic pattern. Both sidewalls of raised portions of the first and second microscopic patterns are formed with wobbling so as to be parallel with each other. Auxiliary information and a reference clock is recorded on these sidewalls alternately and continuously.

Abstract: The present invention provides a composition for hard coat capable of forming a hard coat layer having the improved anti-staining property, anti-staining durability, scratch resistance, abrasion resistance, antistatic property and the like. A composition for hard coat comprising: an active energy ray-curable silicone-acrylic copolymer (A); an active energy ray-curable polyfunctional compound (B); and an electrically conductive material (C), wherein the active energy ray-curable silicone-acrylic copolymer (A) contains: a polysiloxane block (a-1), an acrylic block (a-2) containing an active energy ray-curable double bond group, and a fluoroalkyl group-containing acrylic block (a-3).

Abstract: Substrates for perpendicular magnetic recording media, and perpendicular magnetic recording media using such substrates, are disclosed. By setting the substrate inclination angle, or a parameter related to substrate shape relating to this angle, within an appropriate range, magnetic recording media can be obtained with excellent read signal quality and signal quality stability, regardless of the final substrate machining method.

Abstract: A substrate for a recording medium suited for thermally assisted recording methods has a disc shape with a center hole and includes a silicon single-crystal supporting member; an SiO2 film formed on the silicon single-crystal supporting member; a main face having a film thickness of the SiO2 film thereon which is less than 10 nm; a substrate inner periphery end face adjacent to the center hole; a substrate inner periphery chamfer portion adjacent to the main face and to the substrate inner periphery end face; a substrate outer periphery end face positioned on the side of the main face opposite the substrate inner periphery end face; and a substrate outer periphery chamfer portion adjacent to the main face and to the substrate outer periphery end face. A magnetic recording medium includes at least the above substrate and a magnetic recording layer formed on the substrate.

Abstract: An information recording medium comprises a substrate, a second recording layer, a second light transmitting layer, a first recording layer for recording different information from that to be recorded in the second recording layer, and a first light transmitting layer. The second recording layer is formed with a continuous second microscopic pattern of grooves. The first recording layer is formed with a continuous first microscopic pattern of grooves that is different from the second microscopic pattern. Both sidewalls of raised portions of the first and second microscopic patterns are formed with wobbling so as to be parallel with each other. Auxiliary information and a reference clock is recorded on these sidewalls alternately and continuously.

Abstract: The present invention relates to a data record carrier of the type with ferroelectric memory layer, its method of manufacture and a micro-tip recording system incorporating same. The invention applies in particular to computer-based or multimedia applications requiring high memory capacities. A record carrier according to the invention comprises a substrate, a counter-electrode deposited on the substrate and intended to cooperate with an electrode of a data reading and/or writing device, and at least one ferroelectric memory layer which is able to store these data and which exhibits a first face in close contact with said counter-electrode. According to the invention, the counter-electrode is made of a substance comprising a carbonaceous material chosen from the group consisting of carbon in the form of graphite or amorphous diamond, the carbides of a metallic or non-metallic element with the exclusion of ionic carbides, and their mixtures.

Abstract: The invention discloses an information recording medium comprising a disc body, an ink-receiving layer, and a stacker ring. The disc body comprises a non-data side and a data side. The ink-receiving layer is provided on the non-data side. The ink-receiving layer has an outer radius larger than 57 mm and an inner radius smaller than 20 mm. The stacker ring is located near the center of the data side. The stacker ring has a radius smaller than 11 mm. Specifically, the radius of the stacker ring should be smaller than the inner radius of the ink-receiving layer. Accordingly, a larger area pattern can be printed on the information recording medium of the invention. Furthermore, since the stacker ring does not contact the ink-receiving layer, the information recording medium will not adhere to another under high temperature and high humidity after a period of transportation.

Abstract: A three-level recording phase-change optical disc including a first recording layer, a second recording layer, a third recording layer, a reflective layer, and a dielectric layer is provided. The first recording layer, the second recording layer, and the third recording layer can form three recording regions with three different reflective indexes respectively so as to increase the recording density of the optical disc.

Abstract: In forming a space layer of a multi-formation-layer recording medium, there are provided a medium having a high precision in a thickness of the space layer and its manufacturing process. In the multi-formation-layer recording medium wherein at least two pairs of an information recording layer and a translucency spacer are layered on a substrate having physical patterns composed of an optical spot groove and/or pits on the surface, an average thickness of the translucency spacers in an information zone is 15 ?m or less, and a difference in spacer thickness between a minimum value and a maximum value is 2 ?m or less.

Abstract: A transfer layer on a surface of a mold has a thickness distribution along the radius direction that the layer is thick in an inner round portion but is gradually thinner toward an outer round portion. An adhesive layer is formed between a surface of a signal substrate which bears a signal recording film and the mold which seats the transfer layer. The adhesive layer has a thickness distribution that the layer is thin in an inner round portion but is gradually thicker toward an outer round portion. Since the thickness distributions along the radius direction of the transfer layer and the adhesive layer are opposite to each other, the thickness distribution of an isolation layer which comprises the two layers is uniform.

Abstract: A printing system including a boronic acid dye and a coated print medium. The boronic acid dye comprises a boric acid group or a boronic acid group attached to the dye. The boronic acid dye covalently binds to a polyhydroxylated material present in a coating layer of the print medium, fixing the boronic acid dye to the print medium. A method of reducing dye migration on a print medium is also disclosed.

Abstract: Preventing a molded disc substrate from generating a separation pattern. To this end, a molding die 1 includes a pair of stationary die 6 and movable die 7, and an outer circumference ring 16 for molding an outer circumference end of the disc substrate 2. The outer circumference ring 16 is so mounted as to be movable along forward and backward directions in parallel with a moving direction of the movable die 7 toward the stationary die 6, and has a retaining surface 39 for retaining the outer circumference of the molded disc substrate 2.

Abstract: A limited-life storage medium comprises a flowable agent. In one example, the storage medium is an optical disc. In a ready-to-read condition, the center of mass of the disc does not coincide with the center of rotation. When the disc is read, the unbalanced rotation of the disc causes vibration that migrates the flowable agent into contact with a metal data-carrying layer, where the flowable agent interferes with the readability of the data so as to limit the useful life of the disc. The movement of the flowable agent improves the balance of the disc, and reduces the vibration.

Abstract: An information recording medium includes an insulating member, first and second electrodes formed in one plane of the insulating member, and a conductive layer having an electrochromic material providing continuity with the first and second electrodes. A gap between the first and second electrodes is insulated.

Abstract: A method is disclosed to purify a polymeric material by filtering a melt comprising poly(arylene ether) and poly(alkenyl aromatic) through a melt filtration system. The method provides a filtered polymeric composition having reduced levels of particulate impurities. The filtered polymeric composition prepared is suitable for use in data storage media applications.

Abstract: A recording medium includes a substrate, and a recording layer formed on the substrate having (a) a recording track band, and (b) recording cells regularly arrayed in the recording track band to form a plurality rows of sub-tracks. The recording cells included in each sub-track are formed apart from each other at a pitch P in the track direction. Nearest neighboring two recording cells, each positioned on adjacent two sub-tracks in the track band, are formed apart from each other at a pitch P/n in the track direction, where 2?n?5.

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? under shock or vibration excitation.

Abstract: A method is disclosed to purify a polymeric material by filtering a melt comprising poly(arylene ether) and poly(alkenyl aromatic) through a melt filtration system. The method provides a polymeric material having reduced levels of particulate impurities. The polymeric material prepared is suitable for use in data storage media applications.

Abstract: Provided are a manufacturing method for a magnetic recording medium enabling efficient and reliable manufacturing of a magnetic recording medium with minimal surface roughness and good precision in recording and reading information, and a magnetic recording medium with a high degree of surface recording density and good precision in recording and reading information. The magnetic recording medium is constructed by forming a divided recording layer and the like onto a substantially flat base surface of a dummy, such that the base surface side of the dummy serves as a front surface, and a substrate is also attached, after which the dummy is removed.

Abstract: A process for forming magnetic target tracks for position and speed sensors. The tracks are formed from a paste comprising a magnetic powder material and a hardenable carrier. The tracks can be formed within trenches in a substrate or on the substrate surface.

Abstract: An optical information recording medium which makes it possible to reduce the noise level and improve the C/N ratio. An optical information recording medium has a recording layer formed on a substrate, for having a laser beam irradiated thereto for recording and reproducing record data. The recording layer includes a first sub-recording film and a second sub-recording film. The first sub-recording film is formed of a first material containing Si as a main component. The second sub-recording film is formed of a second material containing Zn as a main component and having Al added thereto, and disposed in the vicinity of the first recording film. The laser beam is irradiated to the recording layer via a light transmitting layer formed in a manner covering the recording layer.

Abstract: An optical information recording medium which makes it possible to reduce the noise level and improve the C/N ratio and store record data for a long time period. An optical information recording medium has a recording layer formed on a substrate, for having a laser beam irradiated thereto for recording and reproduction of record data. The recording layer includes a first sub-recording film and a second sub-recording film. The first sub-recording film is formed of a first material containing Si as a main component. The second sub-recording film is formed of a second material containing Al as a main component and having Mg added thereto, and disposed in the vicinity of the first recording film. The laser beam is irradiated to the recording layer via a light transmitting layer formed in a manner covering the recording layer.

Abstract: An optical information recording medium which is capable of performing high-density recording of record data, and storing the recorded data for a long time period such that the recorded data can be normally reproduced during the long time period. An optical information recording medium has a recording layer formed on a substrate, for having a laser beam irradiated thereto for recording and reproduction of record data. The recording layer includes a first sub-recording film and a second sub-recording film. The first sub-recording film is formed of a first material containing Si as the main component. The second sub-recording film is formed of a second material containing Cu as the main component and having Si added thereto, and disposed in the vicinity of the first recording film.

Abstract: In one aspect the present invention provides a storage medium for data, the storage medium comprising: a) a substrate, a physical portion of which comprises at least one polyimide, and b) at least one data layer on the substrate. The substrate comprising a polyimide exhibits low axial displacement and beneficial damping characteristics.

Abstract: A recording medium includes a substrate, and a recording layer formed on the substrate having (a) a recording track band, and (b) recording cells regularly arrayed in the recording track band to form a plurality rows of sub-tracks. The recording cells included in each sub-track are formed apart from each other at a pitch P in the track direction. Nearest neighboring two recording cells, each positioned on adjacent two sub-tracks in the track band, are formed apart from each other at a pitch P/n in the track direction, where 2?n?5.

Abstract: At least one information layer including a recording layer contains a material that can exhibit a transition between two optically different states in response to irradiation with a laser beam as a main component is provided on a substrate, and the material is configured so as to exhibit an energy gap ranging from 0.9 eV to 2.0 eV in the amorphous state. The information layer is configured to have a light transmittance of not less than 30% when irradiated with a laser beam having a wavelength ranging from 300 nm to 450 nm. It is possible to achieve excellent recording/reproduction, even if a plurality of recording layers are provided in the recording medium, when this medium is irradiated with a laser beam with a wavelength in the foregoing range from one side of the medium.

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 information recording medium comprises a substrate, a second recording layer, a second light transmitting layer, a first recording layer for recording different information from that to be recorded in the second recording layer, and a first light transmitting layer. The second recording layer is formed with a continuous second microscopic pattern of grooves. The first recording layer is formed with a continuous first microscopic pattern of grooves that is different from the second microscopic pattern. Both sidewalls of raised portions of the first and second microscopic patterns are formed with wobbling so as to be parallel with each other. Auxiliary information and a reference clock is recorded on these sidewalls alternately and continuously.

Abstract: A recording medium includes a substrate, and a recording layer formed on the substrate having (a) a recording track band, and (b) recording cells regularly arrayed in the recording track band to form a plurality rows of sub-tracks. The recording cells included in each sub-track are formed apart from each other at a pitch P in the track direction. Nearest neighboring two recording cells, each positioned on adjacent two sub-tracks in the track band, are formed apart from each other at a pitch P/n in the track direction, where 2?n?5.

Abstract: Constructed is an optical recording medium which is so formed as to have excellent surface flatness and with respect to which information is recorded or reproduced with the use of a near-field optical system. The optical recording medium is one which performs at least one of recording and reproduction of information by irradiation of light. The optical recording medium has a substrate 1 which has fine concavities and convexities 2 formed on the surface on a side where irradiation of light is performed, and a formed film layer having at least a recording layer and having a fine concavities and convexities surface reflecting the fine concavities and convexities 2 in itself.

Abstract: An injection molded thermoplastic magnetic recording substrate a medium formed therewith, and a method thereof is composed of a thermoplastic or allyloxymethylstyrene type resin.

Abstract: An optical recording medium having at least a recording layer 11 and a light transmitting layer 13 formed on a substrate 10, in which the recording layer 11 is made of an organic material for absorbing an incident light of wavelength of 360 nm to 460 nm, and inducing physical change or chemical change to vary the refractive index, the light transmitting layer 13 is 10 ?m to 177 ?m in thickness, the relation between absorption coefficient “k” and pyrolysis temperature Tdec of organic material is 950(° C.)<(Tdec (° C.)?20)/k<4100° C.??(1), and the absorption coefficient “k” is k>0.0.

Abstract: The present invention provides an ultraviolet-curable composition having satisfactory protective performance even in endurance testing at high temperature and high humidity in an optical recording medium having for its reflective film Ag or a metal and/or alloy having Ag for its main component, and an optical recording medium in which it is applied. A cured film of an ultraviolet-curable composition, for which the pH value of a 1 wt % methanol solution of said ultraviolet-curable composition is within the range of 4.5 to 6.8, is coated onto a reflective film in the form of a protective film.

Abstract: A disc-shaped recording medium having transcription characteristics for fine signals simultaneously with resonance characteristics and stiffness which are characteristics contrary to the transcription characteristics. At least a recording layer and a light transmitting layer are sequentially formed on a substrate and light is illuminated from a light transmitting layer side to record and/or reproduce information signals. The substrate includes a core layer formed of a resin composition comprised of a mixture of two or more resin sorts. The resin composition has tan?, as an index indicating the internal loss, equal to not less than 0.015 as a system in its entirety. The resin composition constituting the core layer is a compounded resin of the incompatible system and is of an islands-sea structure.

Abstract: An optical data storage device for multi-level recording having: a substrate, and a phase change memory medium supported by the substrate. The phase change memory medium preferably has an alloy with a eutectic crystallization base component and at least one element for enhanced sigma-to-dynamic range. The multi-level data storage device is preferably an optical disk with a single layer of memory material for providing multi-level recording with a sigma-to-dynamic range of less than 2%. The phase change recording alloy is preferably an In:Sb:Te material. Preferably, Sb:Te is present at a ratio at, or near, the eutectic point when combined with 30% or less In. A preferred phase change memory material includes an alloy defined by the formula: Inx(SbnTe100-n)100-x where x is 3-30, and n is 63-82.

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: The disk-shaped optical information medium of this invention includes: a first substrate having a center hole; a second substrate having a center hole; and a radiation curable resin interposed between the first and second substrates for bonding together the first and second substrates, wherein the optical information medium further includes a stopper for preventing the radiation curable resin from protruding into the center holes of the substrates, and a space between the first and second substrates of at least half of a clamp region for clamping the optical information medium is filled with the resin.

Abstract: The present invention provides an optical disk 9 with a duplication preventing function, reproducing system 47 for the optical disk 9, optical disk reproducing method, method of fabricating an optical disk original record, and illegal program operation stopping method. An area in which a CP signal 24 is recorded is made after a signal having a constant pattern in the optical disk, the CP signal 24 being produced such that the center of an eye pattern is shifted from the center of the amplitude. In the reproducing system, CP signal arrangement information 25 or a CP preceding signal 26 is detected, before an offset voltage is applied to a threshold value to be used in demodulating an RF signal into a digital signal so that the threshold value varies, thus normally reproducing the signal in which center of the eye patter is shifted from the center of the amplitude. The reproducing system has a function whereby the reproduction is stopped when a predetermined offset signal is not reproduced.