Abstract: An optical recording medium is provided. The optical recording medium includes at least a reflective film and a cover layer on a substrate; main data by a combination of pit and land are recorded on the substrate; a write-once recording is made to be possible on the reflective film by irradiating a laser light; sub-data are recorded by a mark that is formed by the irradiation of laser light for the write-once recording with respect to the reflective film; a reproducing signal level at portion where said mark is formed increases for the land of specified length; the mark by which the reproduced level decreases at the portion where the mark is formed is formed for an optical disc recording medium manufactured by physical copy; the reflective film is composed of an Ag-alloy film of Ag100-xXx(0<x<100); and the X is selected from Ti, W, Ta, V, Mo, Nb and Zr.

Abstract: A write-once information recording medium having a high recording sensitivity and reliability with respect to long-term storage is provided. The information recording medium has a recording layer on a substrate, to which information can be recorded and from which information can be reproduced by irradiating the recording layer with laser light or applying electrical energy to the recording layer. The recording layer contains, as its primary components, TeO2 and a material A, where the material A is a material that exhibits a eutectic reaction with TeO2.

Abstract: The present invention is aimed to provide a high-performance single-sided double-layer optical recording medium with reduced crosstalk between recording marks, wherein favorable recording signal properties are obtained even from the second recording layer located more distant from the substrate to which the light is applied, and reproducing method thereof, and an optical recording and reproducing apparatus. The optical recording medium possesses the following aspects: the optical recording medium comprises a first substrate, a first information layer, an intermediate layer, a second information layer and a second substrate in this order; the first information layer comprises a first recording layer; the second information layer comprises a second reflective layer, a second recording layer with an organic dye and a protective layer; and the pyrolysis temperature range, the DTA peak width of the thermal analysis on the organic dye in the second recording layer, is 45° C. or less.

Abstract: To provide a sputtering target for preparing a recordable optical recording medium characterized by comprising Bi and B and a manufacturing method thereof, a recordable high density optical recording medium using the sputtering target, and a sputtering target which is capable of improving a speed of the film formation for the improvement of productivity, which has a high intensity at the time of the film formation and which has a heightened packing density.

Abstract: Methods and systems for content distribution are provided that include a broadcast transmitter for transmitting a signal that comprises content, a receiver for receiving the signal, and an optical disc recorder coupled to the receiver for recording the content to an optical disc, which may be an optically altered optical disc.

Abstract: A next-generation optical recording medium has two or more information layers which include a translucent information layer. The translucent information layer has a recording film and an interface layer, provided adjacent to the recording film on the side of the light incident surface. The recording film is made of a phase change material having SbxTeyGez elements and elemental ratios. Y satisfies 5?y?15 and z satisfies 5?z?15. When In having an elemental ratio of a is further added and x+y+z+a=100 holds, a satisfies 4?a?15. The interface layer comprises of ZrO2—Cr2O3 film thickness of which is in a range of from 2 nm to 10 nm. When ZrO2:Cr2O3?C:D (mol %), the compositional ratios ZrO2 and Cr2O3 in the ZrO2—Cr2O3 film, holds, the C satisfies 20?C?90, and the D satisfies 10?D?80, and the C and the D satisfy C+D=100. The ZrO2 is stabilized ZrO2 which contains Y2O3, when ZrO2:Y2O3=(100?X):X (mol %), the compositional ratios ZrO2 and Y2O3 in the stabilized ZrO2, holds, the X satisfies 2?X?10.

Abstract: An optical article configured to transform from a pre-activated state of functionality to an activated state of functionality is provided. The optical article includes an optical data layer for storing data, wherein the data is read from the optical data layer in an activated state of functionality, and a material capable of undergoing a morphological transformation being disposed on the optical data layer and adapted to irreversibly alter from a first morphology to a second morphology upon interaction with the external stimulus to alter the state of functionality of the optical article from a pre-activated state to the activated state.

Abstract: There are provided a patterned member which has densely arranged pits on the surface and which is easily manufactured, and a method for manufacturing such a patterned member. A patterned member includes a substrate 10, a thermally deformable heat mode photoresist layer 20 provided on the substrate 10, pits 21 formed on the photoresist layer 20. The pits 21 are arranged in line along a plurality of tracks which are substantially parallel to one another, and as viewed in a direction along which the tracks Tn extend, each pit 21 on one track is positioned at a position corresponding to a midpoint between two adjacent pits arranged on an adjacent track.

Abstract: A thin film for a reflection film or for a semi-transparent reflection film, having a compound phase formed of at least one chemical compound selected from the group consisting of a nitride, an oxide, a composite oxide, a nitroxide, a carbide, a sulfide, a chloride, a silicide (excluding silicon), a fluoride, a boride, a hydride, a phosphide, a selenide and a telluride of aluminum, magnesium, tin, zinc, indium, titanium, zirconium, manganese and silicon, dispersed in a matrix formed of silver or a silver alloy. The thin film may disperse at least one compound selected from the group consisting of a nitride, an oxide, a composite oxide, a nitroxide, a carbide, a sulfide, a chloride, a silicide, a fluoride, a boride, a hydride, a phosphide, a selenide and a telluride of silver, gallium, palladium or copper, in addition to aluminum or the like, therein.

Abstract: An information recording medium (300) of the present invention is an information recording medium on or from which information can be recorded or reproduced by irradiation with an optical beam (10), and includes a dielectric layer b, a recording layer (335), and a dielectric layer a in this order from an optical beam (10) incident side. The dielectric layer a and the dielectric layer b are layers disposed in contact with the recording layer (335), and an interface layer (334) corresponds to the dielectric layer a and an interface layer (336) corresponds to the dielectric layer b. The dielectric layer a contains Cr, O, and at least one element M selected from Al, Dy, Nb, Si, Ti and Y. The dielectric layer b contains Cr, O, and at least one element A selected from Zr and Hf.

Abstract: A Flexible VCD Having Domed Center and Method of Making Thereof is disclosed. The disc will has a flat data storage section of its substrate that is less than 0.7 millimeters thick, while the central region of the disc is defined by a dome structure adjacent to the spindle aperture that is of standard digital disc thickness. The disc is thin enough such that its substrate is flexible. The dome structure is shaped to provide the widest compatibility with player/recorders, as well as with disc printing systems. Disc versions are available that provide conical dome structures, as well as slivered dome structures of both conical and rectangular cross-section. The method for manufacturing the discs simply requires the replacement of the conventional stamper holder with a stamper holding having a non-flat face.

Abstract: In each of at least two information layers (1, 2) which constitute a information recording medium having a plurality of information layers on its one side, the compositions of the recording layer (7) and the dielectric layers (6, 8) adjacent to the recording layer (7) in one information layer (1) are common to the compositions of the corresponding layers (12, 11, 13) in the other information layer, so that the recording layers (7, 12) and the dielectric layers (6, 11) and (8, 13) in the two information layers (1, 2) can be formed in common sputtering film-forming chambers without the replacement of targets, which makes it possible to produce a multi-layer single-sided recording medium with a decreased time loss in the production process.

Abstract: An optical recording medium is provided which includes two or more information layers in which an Sb-based eutectic material is used as the material for a recording film of a translucent information layer. There is also provided a recording film material for the optical recording medium. The translucent information layer is configured to include a recording film formed of a phase change material SbxGeyInz containing Sb, Ge, and In in an atomic ratio of x:y:z, where 5?y?15 and 4?z?15 are satisfied. The recording film further includes Te in an atomic ratio of a, provided that x+y+z+a=100 and 4?a?15 are satisfied. An interface layer formed of a ZrO2—Cr2O3 film having a thickness of 2 nm or more and 10 nm or less is provided on the laser beam incident side of the recording film. When the compositional ratio of the ZrO2—Cr2O3 film is given by ZrO2:Cr2O3=B:C (mol %), 20?B?90, 10?C?80, and B+C=100 are satisfied.

Abstract: A novel indolium compound of general formula (I) and an optical recording material containing the indolium compound. In formula (I), ring A is a benzene ring, etc.; ring B is a 5- or 6-membered heterocyclic ring; R1 is a group of general formula (II), etc.; R2 is an organic group having 1 to 30 carbon atoms, etc.; Y1 is an alkyl group having 1 to 10 carbon atoms, etc.; Z1 and Z2 are each, e.g., an alkyl group having 1 to 8 carbon atoms optionally substituted with a halogen atom and optionally interrupted by —O—, etc.; a is an integer of 0 to 6; b is an integer of 0 to 5; Anq? is a q-valent anion; q is 1 or 2; and p is a number necessary to neutralize an electric charge.

Abstract: The invention relates to a master substrate, a method for making a high density relief structure, and optical discs replicated with the high-density relief structure, the master substrate comprising a substrate layer (10) and a recording stack deposited on the substrate layer, the recording stack comprising:—an information layer (12),—an interface layer (11) sandwiched between said information layer and the substrate , forming marks and spaces representing an encoded data pattern, wherein said recording material is an alloy comprising at least two materials of the group of materials containing Ge, Sb, Te, In, Se, Bi, Ag, Ga, Sn, Pb, As. A very high-density relief structure is achieved.

Abstract: A method for selectively marking a surface of an optical disk includes providing an optical disk, wherein the optical disk includes a metal, an electrolyte disposed on the metal, and a photoconductor disposed on the electrolyte, applying a voltage to the optical disk, the voltage being associated with a desired anodization color, and selectively applying a laser to the photoconductor to initiate anodization of the metal.

Abstract: A method of manufacturing an optical data storage medium, comprising at least one substrate (11) and a plurality of layers deposited on the substrate (11) is described. The medium includes at least one of a transparent spacer layer and transparent cover layer (12). The layer (12) is provided by applying a liquid onto the rotating substrate (11) and rotating the substrate (11) further in order to spread out the liquid into a layer substantially uniformly between an inner radius ri and an outer radius ro, and solidifying the liquid layer (12) by means of exposure to UV radiation. After applying the liquid onto the rotating substrate the liquid layer (12) is heated by heating means (14) in such a way that the temperature rise of the liquid layer (12) at ri has a value ?Tri, while the temperature rise of the liquid layer (12) between ri and ro gradually increases, and the temperature rise of the liquid layer (12) at ro has a value ?Tro>?Tri.

Abstract: A small-sized, large-capacity optical disk is provided which is superior in portability. The optical disk has a diameter less than 64 mm and a thickness less than 0.8 mm. Tracks are formed with a pitch less than 0.6 ?m, and the record area is divided into a plurality of zones alone the radium. The optical disk can store more than 650 MB of compressed data.

Abstract: In an optical disc having N (N is an integer larger than or equal to 3) information recording layers of rewritable or recordable type, each of the information recording layers includes an test area to adjust conditions for recording and reproduction and the test areas are arranged so that the radial positions thereof overlap those of other layers. Recording test is performed only to an area smaller than or equal to 1/N of the test area of each layer and any other area is always unrecorded (write inhibited).

Abstract: To accomplish write-once type optical recording mediums that have excellent recording and reproducing characteristics and producibility and that are capable of being fabricated at low cost. A write-once type optical recording medium 10 has the structure of which an inorganic recording film 6, a dielectric film 4, and a light transmission layer 5 have been successively formed on a substrate 1. The inorganic recording film 6 is composed of a metal film 2 and an oxide film 3 successively formed on the substrate 1. When light is radiated to the inorganic recording film 6, oxygen is separated from the oxide film 3 due to the light catalyst effect, resulting in increasing the oxygen concentration on the metal film 2 side and largely varying the optical constant.

Abstract: A transparent protective layer (106) having a thickness of 100 ?m is formed of a resin film (100), a boundary layer (104) and an adhesive layer (103) on a signal recording layer (102). When nf, ni and na are the indices of refraction of the resin film (100), the boundary layer (104) and the adhesive layer (103), respectively, the relationship among nf, ni, and na satisfies any one of the following equation: na<ni?nf; na>ni?nf; na<nf?ni; or na>nf?ni, and the relationship among nf, ni, and na satisfies the following equation |nf?ni|<|nf?na|. At this time, a protrusion (111) and a scratch (110) are optically buried within the boundary layer (104), reducing scattering of laser beams and disturbance in the wave front which occur in these portions, and thereby, the error rate can be reduced.

Abstract: An object of the invention is to provide an optical recording medium and an optical information device that enable to improve the quality of a servo signal and a reproduction signal.

Abstract: An optical recording medium having three or more information recording layers reduces crosstalk caused by multi-reflected beams and improves signal quality. In the optical recording medium having three or more information recording layers, the refractive index of a plurality of intermediate layers disposed between adjacent information recording layers is greater than the refractive index of a cover layer disposed between a light incident surface and an information recording layer being the closest from the light incident surface.

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: A thin film for a reflection film or a semi-transparent reflection film, which has a compound phase comprising at least one selected from the group consisting of a nitride, an oxide, a complex oxide, a nitroxide, a carbide, a sulfide, a chloride, a silicide, a fluoride, a boride, a hydride, a phosphide, a selenide and a telluride of gallium, palladium or copper, dispersed in a matrix formed of silver or a silver alloy. The compound phase in the thin film may include at least one compound selected from the group consisting of nitride, oxide, complex oxide, nitroxide, carbide, sulfide, chloride, silicide, fluoride, boride, hydride, phosphide, selenide and telluride of silver. The thin film of the present invention minimizes the deterioration of the reflectance even after a long period of use, and can prolong the life of various devices which use the thin film as a reflection film, such as an optical recording medium and a display.

Abstract: There is provided a method of manufacturing an optical recording medium capable of reducing a manufacturing cost of an optical recording medium. When manufacturing an optical recording medium 10 including a recording layer 2 formed on a substrate 1, and a light transmitting layer 3 formed on the recording layer 2, the method of manufacturing the optical recording medium includes a step of forming the recording layer 2 containing In and/or Sn, Pd, and oxygen through a use of sputtering method by using an In2O3 target and/or a SnO2 target, and a Pd target while allowing an oxygen gas and a nitrogen gas to flow.

Abstract: The optical storage medium comprises a substrate layer, a read-only data layer with a pit structure disposed on the substrate layer, a cover layer and a nonlinear layer with a super-resolution structure disposed between the data layer and the data layer, which super-resolution structure includes a semiconductor material and grainy impurities of a dielectric material, wherein the semiconductor material has an increased reflectivity, when irradiated with a laser beam, and wherein the dielectric material is arranged as a dielectric layer having a thickness below 5 nm. The dielectric material consists advantageously of an inhomogeneous layer of a nitride material, for example GeN, arranged between a first and a second nonlinear layer.

Abstract: A super-resolution material for recording and reproducing optical information, comprises a semiconductor material which has a transmittance that increases with an increasing intensity of the incident radiation, and one or more elements selected from the group consisting of nitrogen (N), oxygen (O), carbon (C) and boron (B).

Abstract: A code disk for a high-resolution encoder that can detect an absolute position and a method for manufacturing a mold to produce the code disk are provided. The code disk is formed by using transparent substrate. The code disk includes a plurality of tracks provided on the transparent substrate and an area provided between the plurality of tracks. Each surface of the plurality of tracks has a different pattern. A level of the area is different from that of the each surface of the plurality of tracks. The method for manufacturing the mold includes steps of processing a plurality of tracks with a flat surface on material; processing an area with a level different from that of each surface, between the plurality of tracks; forming different patterns on the each surface; plating the first material; and peeling plating from the first material to obtain a mold.

Abstract: A method for producing optical discs is provided. A substrate for an optical disc is formed by utilizing a molding process. A textured surface is formed at an outer diameter edge of the substrate. A protective coating is applied to cover the textured surface at the outer diameter edge. The protective coating adheres securely to the textured surface at the outer diameter edge to prevent seepage of moisture into the optical disc through the outer diameter edge surface. Thus, an improved optical disc which avoids moisture-caused warpage, corrosion and/or oxidation can be formed.

Abstract: An optical recording medium includes: a substrate; an information recording layer formed on the substrate for recording and reproducing an information signal by irradiation with light; and a light transmission layer formed on the information recording layer and transmitting the light, the storage elastic modulus of the light transmission layer at ?5° C. being within a range of 1500 MPa or less.

Abstract: An object of the invention is to improve the quality of a servo signal and a reproduction signal. Shape-wise thicknesses tr1, tr2, . . . , and trN of a cover layer and first through (N?1)-th intermediate layers of an optical recording medium having refractive indexes nr1, nr2, . . . , and nrN are converted into thicknesses t1, t2, . . . , and tN of the respective layers having a predetermined refractive index “no” which makes a divergent amount equal to a divergent amount of a light beam resulting from the thicknesses tr1, tr2, . . . , and trN, a difference DFF between the sum of a thickness “ti” through a thickness “tj”, and the sum of a thickness “tk” through a thickness “tm” is set to 1 ?m or more (where i, j, k, and m are each any positive integer satisfying i?j<k?m?N), and the thicknesses t1, t2, . . . , and tN are calculated by products of a function f(n) expressed by the following formula (1), and the thicknesses tr1, tr2, . . . , and trN: f(n)=?1.088n3+6.1027n2?12.042n+9.

Abstract: Optical recording mediums, and methods and systems for manufacturing optical recording mediums are provided. The optical recording medium includes a substrate on which a recordable layer and a reflective layer are formed. The reflective layer includes a predefined proportion of at least copper and zinc, wherein the predefined proportion is 50-75% copper and 15-45% zinc by mass. The recordable layer can either be formed over the substrate or the reflective layer, and is configured to record data. A protective layer is also formed over the reflective layer or recordable layer.

Abstract: The present invention relates to an ultraviolet-curable resin composition for an optical disk containing a sulfur-containing compound (A) represented by the following formula (1): (wherein, R1 and R2 each dependently represent a hydrogen atom, a hydroxy group, an alkyloxy group, an alkyl group, an aryl group, a carboxy group, an alkylthio ether group or a halogen atom) a photopolymerizable compound (B) and a photopolymerization initiator (C), and an optical disk having a thin film of the cured product of said resin composition, particularly an optical disk having a reflective film comprising silver or a silver alloy; and said optical disk is prevented from changing the properties of its reflective film comprising silver or a silver alloy, and thus has a higher durability.

Abstract: In an information recording medium comprising at least a substrate, a recording layer, and a resin layer, the substrate is formed with at least a pit corresponding to a read only area 31 and a groove corresponding to a recording/reproducing area 32 without overlapping with each other. A reflectivity of the recording layer is specified to be more than 10%. The recording layer and the resin layer are continuously adhered over both the read only and recording/reproducing areas 31 and 32. The information recording medium is characterized in that both push-pull signal outputs T1 and T2, which are reproduced from the read only area 31 and the recording/reproducing area 32 respectively, are more than 0.1 and satisfy an inequality 1.5?T1/T2?0.5.

Abstract: To provide a sputtering target for preparing a recordable optical recording medium characterized by comprising Bi and B and a manufacturing method thereof, a recordable high density optical recording medium using the sputtering target, and a sputtering target which is capable of improving a speed of the film formation for the improvement of productivity, which has a high intensity at the time of the film formation and which has a heightened packing density.

Abstract: The present invention provides an information recording medium with high reliability and excellent repeated rewriting performance even when no interface layer is formed and a method for manufacturing the same. Accordingly, the information recording medium for carrying out recording and/or reproducing by light irradiation or electric energy application has a material layer containing at least one element selected from a group GM consisting of Sn and Ga, at least one element selected from a group GL consisting of Ta and Y, and oxygen.

Abstract: The present invention relates to an Ag alloy film. Particularly, it is preferably used as a reflective film or semi-transmissive reflective film for an optical information recording medium having high thermal conductivity/high reflectance/high durability in the field of optical information recording media, an electromagnetic-shielding film excellent in Ag aggregation resistance, and an optical reflective film on the back of a reflection type liquid crystal display device, or the like. The Ag alloy film of the present invention comprises an Ag base alloy containing Bi and/or Sb in a total amount of 0.005 to 10% (in terms of at %). Further, the present invention relates to a sputtering target used for the deposition of such an Ag alloy film.

Abstract: There is provided a dielectric material containing no sulfur (S), and there is provided an information recording medium that affords high signal quality and excellent recording sensitivity and repeated rewrite characteristics, even though no interface layer is provided between a reflective layer and a dielectric layer. To this end, the present invention is an information recording medium that is equipped with at least a recording layer and undergoes phase change when the recording layer is irradiated with a laser beam or when current is applied, comprising an oxide-fluoride dielectric layer that includes indium (In), an element M1 (where M1 is at least one element selected from among Zr, Hf, Y, Ti, Nb, Ta, Cr, Ga, and Si), oxygen (O), an element M2 (where M2 is at least one element selected from among La, Ce, Pr, Nd, Gd, Tb, Dy, Ho, Er, Yb, Mg, Ca, and Sr), and fluorine (F).

Abstract: A coating composition for optical recording includes a uniform dispersion of polymer particles in a liquid, a quantity of dye particles uniformly dispersed in the liquid, the dye particles being soluble in the polymer but substantially insoluble in the liquid, and a quantity of radiation absorber material adapted to absorb radiation at a wavelength of a laser for optical recording of an image.

Abstract: An optical media disk is treated with a light-sensitive material that impedes the ability of a optical media player from reading data stored on the disk. This light-sensitive material is a material changes phase upon exposure to one or more wavelengths of light. During the initial phase, the light-sensitive material will render the disk unreadable. After activation, however, the disk becomes readable by conventional optical media players. In this fashion, theft of yet-to-be-activated optical media is deterred.

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: An optical disc includes an annular substrate, a coating layer, a damping layer, and a leveling layer. The annular substrate includes a supporting portion, and a recording portion surrounding the supporting portion, wherein the recording portion has a recording surface located on a first side thereof. For disc clamping and cost saving, the supporting portion is thicker than the recording portion. The coating layer is formed on the recoding surface for recording dada. The damping layer is formed on the coating layer to shorten the response time of the optical disc to vibration. The leveling layer is formed on the side of the annular substrate opposite to the recording surface for leveling the disk deformation caused during fabrication. A method for fabricating the aforementioned optical disc is also disclosed.

Abstract: An ultraviolet-curable composition of the present invention includes epoxy(meth)acrylate, urethane(meth)acrylate, and a silicone compound represented by formula (1): (CH3)3Si—O—X—O—Si(CH3)3 ??(1) wherein X represents a group having a structure in which n structural units represented by formula (2): wherein R1 represents an alkylene group of 1 to 18 carbon atoms, and a divalent group connected with one, or two or more groups selected from divalent groups having a structure in which plural alkylene groups of 2 to 18 carbon atoms are connected through an ether bond, R1 may be bonded directly to Si or bonded through an oxygen atom to Si, and R2 represents a hydrogen atom or a methyl group, and m structural unit represented by formula (3): are connected in a random or blocked shape, provided that n is an integer within a range from 1 to 15 and n/m is within a range from 1/5 to 1/20.

Abstract: A conductive composition comprises a ? conjugated conductive polymer, a polyanion, and a hydroxy group-containing aromatic compound containing two or more hydroxy groups. An antistatic coating material comprises the conductive composition and a solvent. An antistatic coating is produced by applying the antistatic coating material. A capacitor comprises an anode composed of a porous valve metal body; a dielectric layer formed by oxidizing a surface of the anode; and a cathode formed on the dielectric layer, wherein the cathode has a solid electrolyte layer comprising the conductive composition.

Abstract: Disclosed is an ultraviolet-curable resin composition containing a polyurethane compound (A), a photopolymerization initiator (B), and an ethylenically unsaturated compound (C) other than the compound (A). The polyurethane compound (A) is obtained by reacting an epoxycarboxylate compound (c), which is obtained by reacting an epoxy compound (a) having two or more epoxy groups in a molecule with a monocarboxylic acid compound (b) having an ethylenically unsaturated group in a molecule, with a diisocyanate compound (d).

Abstract: One inventive aspect relates to an optical information recording medium, in which the quality of a printed image is not impaired because the water resistance of a printed portion is improved. The optical information recording medium includes a porous film ink receiving layer as an outermost layer of a surface opposite to a recording and playback surface, wherein when the ink receiving layer is printed with an ink of each of four colors, cyan, magenta, yellow, and black, followed by drying, a running water test is performed, and L*a*b* values before and after the running water test are measured with a colorimeter, the total value of the square root of the sum of the square of difference in L*, the square of difference in a*, and the square of difference in b*, each between before and after the running water test, of each of the four colors is approximately 20 or less.

Abstract: An optical disc capable of suppressing vibration during read/write process includes an annular substrate, a coated layer, and a damping layer. The annular substrate includes a supporting portion and a recording portion, and a recording surface corresponding to the recording portion. The coated layer is formed on the recording surface. The damping layer is formed on the coated layer side of the annular substrate for increasing the response time to vibration of the optical disc. A method for fabricating the aforementioned optical disc is also disclosed.

Abstract: An optical disc includes a substrate layer, a cover layer, and an aluminum alloy layer that is between the substrate layer and cover layer, and is adjacent to the substrate layer. The aluminum alloy layer includes a majority amount of aluminum and an additional metal selected from the group consisting of: chromium, titanium, tantalum, and any combination thereof. A method of making an optical disc includes the steps of: forming a substrate layer; sputtering an aluminum alloy target onto the substrate layer to form an aluminum alloy layer; and forming a cover layer; wherein the aluminum alloy layer comprises a majority amount of aluminum and an additional metal selected from the group consisting of: chromium, titanium, tantalum, and any combination thereof.

Abstract: A multilayer type optical information recording medium in which in multilayering of a write-once type optical information recording medium, when a second film is formed using a metallic stamper, a protective layer composed of an inorganic material is free from peeling, is provided. In the multilayer type optical information recording medium including an interlayer, the interlayer is constituted by multiple films of a first film contacting a protective layer and a second film contacting a reflection layer; materials of the first and second films are constituted of materials different from each other; and a peeling resistance of the material of the first film against a material of the protective layer of the first optical information recording layer is higher than that of the second film.