Abstract: The same digital data is recorded with highly integrated manner on a plurality of media able to durably hold information over long-term. A minute graphic pattern indicating data bit information is drawn on a resist layer formed on a quartz glass substrate by exposing a beam and developed so as to prepare a master medium (M1), which comprises the quartz glass substrate having a minute recess and protrusion structure formed by etching where the remaining resist are used as a mask (FIG. (a)). The recess and protrusion structure recorded on the master medium (M1) is shaped and transferred onto a flexible recording medium (G2) on which a UV curable resin layer (61) is formed, whereby an intermediate medium (M2) is prepared (FIGS. (b)-(d)).

Abstract: A method for applying a layer having a relief on a substrate includes steps of securing the substrate, applying a layer of a curable liquid on the substrate, bringing a mould having a relief being the negative of the relief to be provided on the substrate, into contact with a part of the upper surface of the liquid layer, curing the liquid layer while the mould is in contact with the liquid and separating the mould from the substrate. Initially the mould is brought into contact with the liquid in a bent position while the substrate is kept flat and subsequently the mould is brought into contact over an increasing surface area keeping the mould in a bent position until the complete liquid layer is in contact with the mould.

Abstract: A recording medium having an outer surface relatively free of magnetic particulates is achievable by, after forming a magnetic recording layer with which magnetic contamination is associated, removing magnetic contamination from the medium by immersing the medium in an acidic water solution. For example, a post-sputter wash process utilizing a mildly acidic water solution having a pH less than around 5 may remove cobalt particle contaminants from the surface of the medium. The water solution may be acidized by introducing into deionized water a pre-diluted strong acid such as nitric acid or a weak acid such as carbonic acid.

Abstract: The invention is directed to new nanoimprint resist and thin-film compositions for use in nanoimprinting lithography. The compositions permit economical high-throughput mass production, using nanoimprint processes, of patterns having sub-200 nm, and even sub-50 nm features.

Abstract: A mold for forming a resin pattern using nanoimprint lithography according to the present invention comprises a main mold including a fine pattern of a protrusion and a depression intended to be transferred, and a spacer for forming a space between the protrusion of the fine pattern of the main mold and a transferred object during a transfer of the fine pattern, in which the spacer has a vent passage capable of flowing gas therethrough and has an elasticity against a pressing force during the transfer.

Abstract: An apparatus for transferring a pattern of minute surface structures, using a pair of press members which are located opposingly for movements toward and away from each other. One press member is adapted to support thereon a mold having on a transfer surface a master pattern of minute structures to be transferred, while the other press member is adapted to support thereon an annular substrate plate having a curable resin layer coated thereon and to press the resin layer against the transfer surface of the mold to transfer said minute structures to the resin layer. The mold is provided with a circular center hole defining at least three small-diameter segments and three large-diameter segments alternately and at uniform angular intervals along an inner periphery of the mold. The annular substrate plate has an inside diameter exactly matching with the small-diameter segments at the inner periphery of the mold.

Abstract: The present invention relates to a liquid crystal display (LCD) device, and more particularly, to a method of fabricating a color filter for an LCD device. A method of fabricating a color filter uses a mold (PDMS mold) having a plurality of grooves. Particularly, the mold (PDMS mold) is attached to a substrate such that the plurality of grooves face into the substrate. When a color resin is dropped into a side opening of each groove, the color resin is injected into each groove of the mold (PDMS mold) by a capillary force. After the mold (PDMS mold) having the injected color resin is cured, the mold (PDMS mold) is detached from the substrate and a color filter pattern is formed at a desired position.

Abstract: A device (4) for transferring a pattern to an object (2). The invention relates especially to production of micro and nanostructures. The device comprises an alignment means (10) arranged in connection with a first contacting means (7) for controlling the motion of the first stamp (8) in a direction perpendicular to the pressing direction (A), and a second contacting means (11) having a second stamp (12) adapted to imprint a second pattern in the second surface (6) of the object (2), and a pressing means (9) further adapted to press the second stamp (12) into contact with the second surface (6) of the object (2) in the pressing direction (A). Hereby is obtained a device of a simple design, which has a high accuracy of the alignment of the stamps in relation to the object.

Abstract: A process and apparatus for producing a stabilized product from a pledget, including the steps of providing a pledget, a transfer member having an expandable portion, and a stabilization mold having an interior surface defining an interior cavity. The pledget is pushed into the mold by the transfer member so that the expandable portion is within the interior cavity of the mold. The pledget is compressed in the mold by the transfer member to form a compressed pledget. The expandable portion of the transfer member is expanded to form a seal with the interior surface of said mold. The compressed pledget is stabilized to form a stabilized product, while the compressed pledget is maintained in compression and the expandable portion of the transfer member remains expanded.

Abstract: An optical disk is constructed such that a thin film including a reflective layer is formed on a substrate, or on a thermoplastic resin layer on the substrate. A stamper having an asperity pattern corresponding to information signals is directly pressed against the thin film to transfer the asperity pattern on the thin film. Heat-pressing the stamper against the thin film makes it possible to further accurately transfer the asperity of the stamper to the reflective layer with less pressing force in the case where the reflective layer is formed on a thermoplastic resin layer.

Abstract: A method of aligning die and stamping substrate for nano-imprint lithography is described. The method includes aligning the die by linearly displacing the die along a first axis using a first flexure member and pressing the die along a second axis substantially perpendicular to the first axis while maintaining coupling of the die with the first flexure member.

Abstract: A method of molding provides two molds (102, 104) formed of semiconductor material. The molds (102, 104) have substantially planar working faces (108, 110) into which recesses (106, 112) are formed. In use the molds (102, 104) are pressed together with the working faces (108, 110) opposed so the recesses (106, 112) form mold cavities. The molds (102, 104) only contact each other in the plane of the working faces (108, 110). A thermoplastic sheet placed between the molds is heated to deform the sheet into the mold cavities.

Abstract: The present invention makes it possible to strip off a stamper stuck on a resin layer for groove formation during the manufacture of an optical disc from the resin layer without imparting damage or the like to the stamper. The present invention achieves this object by having the steps of bringing about a state in which the stamper protrudes from a substrate by a predetermined width, rotating the substrate with the back surface of the disc-shaped substrate attracted and held, elevating rollers capable of rolling relative to a contacting surface contacting with the protruding portion simultaneously with the rotation, and continuously applying a force working in a direction to separate the protruding portion from the substrate in the circumferential direction of the stamper.

Abstract: An optical disk is constructed such that a thin film including a reflective layer is formed on a substrate, or on a thermoplastic resin layer on the substrate. A stamper having an asperity pattern corresponding to information signals is directly pressed against the thin film to transfer the asperity pattern on the thin film. Heat-pressing the stamper against the thin film makes it possible to further accurately transfer the asperity of the stamper to the reflective layer with less pressing force, in the case where the reflective layer is formed on the thermoplastic resin layer.

Abstract: A die for molding a disk substrate capable of forming fine recessed and projected pits and grooves up to the outer periphery of the disk substrate by preventing low heat conductive elements from peeling off and burrs from occurring on the outer periphery thereof. The die includes a first base die, a second base die disposed oppositely to the first base die, a first low heat conductive element fixed to the first base die, a stamper fixed onto the first low heat conductive element, a second low heat conductive element fixed onto the second base die, and a ring-like regulating member fitted to and in slidable contact with either of the first and second low heat conductive elements. The die is characterized in that the end part of the ring-shaped regulating member is positioned within the range of the outer peripheral side face of the low heat conductive element in slidable contact therewith.

Abstract: A method of producing a stamper, an optical recording medium produced by molding using the stamper, and a method of producing the same, wherein a base member having a mirror polished main surface and comprising silicon or glass is formed with a resist film; the resist film is exposed by a focused electron beam, an ultraviolet ray laser, etc. and developed so as to form a resist film of a pattern corresponding to relief shapes; the mirror surface of the base member is processed to relief shapes (projecting regions and recessed regions) by dry etching etc. using the obtained resist film as a mask so as to obtain a stamper; the obtained stamper is used for injection molding to form a medium substrate; and an optical recording multilayer film and a protective layer are formed to thereby produce an optical recording medium.

Abstract: A stamper suppressed in surface roughness, uneven thickness, and deviation of circularity in inner circumference, a method of producing the same, an optical recording medium produced by molding using the stamper, and a method of producing the same, wherein a base member having a mirror polished main surface and comprising silicon or glass is formed with a resist film; the resist film is exposed and developed so as to form a resist film of a pattern corresponding to relief shapes; the mirror surface of the base member is processed to relief shapes (projecting regions and recessed regions) by dry etching etc. using the obtained resist film as a mask so as to obtain a stamper; the obtained stamper is used for injection molding to form a medium substrate; and an optical recording multilayer film and a protective layer are formed to thereby produce an optical recording medium.

Abstract: The present invention is a method and system of marking data media products by introducing a predetermined tracing substance constituting a security marking into a polycarbonate (or polystyrene) composition during the manufacturing stages of the polycarbonate material into a data media, such as a compact disc (CD) or digital versatile disc (DVD). This marking technique is useful in tracking pirated data and/or sources, such as CDs or DVDs, to thereby prevent future pirating of data. Using mass spectrometry, specific types and/or quantities of isotopes of each tracing substance, on a structural level, are used to indicate a specific marking and product identity characteristics, such as a specific lot number, batch number, manufacturer identity, shipping date and the like. The security marking is preferably invisible to the naked eye. The security marking technique is also useful for tracking, authenticating and quality control purposes.

Abstract: A stamper/imprinter for use in performing thermal imprint lithography of a substrate/workpiece surface to form a pattern of features in first portions of the surface intended to receive the pattern, without incurring random formation of undesired, disordered features in second portions of the substrate/workpiece surface not intended to receive the pattern, comprising an imprinting surface configured to substantially prevent formation of gaps between the imprinting surface and the second portions of the surface during stamping/imprinting. Embodiments include stampers/imprinters with a multilevel imprinting surface comprises a first portion having a first level for forming the pattern of features in the first portions of the surface and a second portion having a second level for substantially preventing formation of gaps between the imprinting surface and the second portions of the surface during stamping/imprinting.

Abstract: A stamper-forming electrode material contains Cu as its main ingredient and at least one other element, preferably Ag and/or Ti. It is preferred that the Ag content be 10.0 wt % or less and that the Ti content be 5.0 wt % or less. A stamper-forming thin film is made of this stamper-forming electrode material, whereby its corrosion resistance is improved to suppress damage to itself, and a high-quality stamper can hence be formed.

Abstract: Without forming a center hole, a light-transmitting resin layer is deposited and formed on a disc-shaped substrate material. A method for fabricating an optical disc includes the steps of injecting a synthetic resin from a gate into the cavity of a mold assembly 30 to mold and cure a disc-shaped substrate material 12 in conjunction with a sprue runner 14 in the gate; depositing a film 18 on the disc-shaped substrate material 12 integrated with the sprue runner 14 taken out of the mold assembly 30; forming a light-transmitting resin layer 22; and forming a center hole 28 by punching through a center portion 26 of the disc-shaped substrate material 12 in conjunction with the sprue runner 14.

Abstract: An information recording medium preform is used to manufacture an information recording medium which has a center mounting hole formed in a central part thereof, has at least one type of functional layer formed on a first surface thereof, and for which at least one of recording and reproduction of information is possible. A second cavity that is formed as one of a circular recess and a ring shaped concave and composes part of the center mounting hole on the first surface side is formed in a central part of the first surface of the information recording medium preform. A first cavity that is formed as a recess and composes part of the center mounting hole on a second surface on another side of the information recording medium is also formed in a central part of the second surface of the information recording medium preform.

Abstract: A method of manufacturing a magnetic stamper/imprinter for use in patterning of magnetic recording media by means of a contact printing process, comprising sequential steps of: (a) providing a stamper/imprinter comprising a body of a magnetic material having an imprinting surface including a topographical pattern corresponding to a pattern to be formed in the surface of a magnetic or magneto-optical (MO) recording medium and comprising a patterned plurality of spaced-apart recesses with a plurality of non-recessed areas therebetween, said imprinting surface including a plurality of defects comprising surface blemishes and stains, magnetic particles, and non-magnetic particles; (b) initially removing the surface blemishes, stains, and magnetic particles; and (c) then removing or rendering the non-magnetic particles benign to the contact printing process.

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: 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: The invention relates to a process for determining pressing parameters for the pressing of compacts, whereby in one step a test compact is brought to the required density in order to achieve the nominal pressing force, and in order that consequently the machine is in a balanced deflected condition with regard to this nominal pressing force. In next step, in case a nominal height (hsi,Nominal) deviates from a height (hsi,Measure) measured on the test compact, there will be determined for the next pressing operation a required height (HPowderNew) of the material to be pressed in the pressing mold.

Abstract: A method and apparatus for making multiple layer optical discs is applied to separate the base plate from the mold plate. The base plate is formed with a first opening, an empty zone and a data zone having a first recording layer. The apparatus includes a first adhesive ending groove, a mold plate, a sealing member and an air-blowing axle. The first adhesive-ending groove is formed on the empty zone of the base plate. The mold plate, movably pressed on the base plate, includes a main body, a second opening, a second adhesive ending groove, a second recording layer and an adhesive layer. The second opening is located on the main body at a position corresponding to the first opening of the base plate. The second adhesive-ending groove is located on the main body at a position corresponding to the first adhesive-ending groove of the base plate.

Abstract: There is disclosed a molding die which can prevent or restrain a wedge-like deformation from being formed at an outer peripheral portion of an optical recording disk. The molding die is for molding a thin circular plate optical recording disk by injecting a molten thermosetting resin in a cavity, and an outer peripheral member coming in contact with a portion which becomes an outer peripheral surface of the optical recording disk is made of a material having a thermal conductivity lower than a thermal conductivity of a material of an opposite member coming in contact with a portion which becomes a main surface of the optical recording disk, that is, a stamper, a stationary mirror, and a movable mirror.

Abstract: In a method of manufacturing a mold for forming an information pattern including servo information or address information on a substrate of a recording medium by being pressed onto the heated substrate, carbon is used as a material for the mold. A mask corresponding to the information pattern is formed on the mold made from carbon of the present invention. Said carbon plate is etched in areas having no mask formed thereon, and lastly the mask is removed.

Abstract: An injection-moulding tool (10) for the production of information carriers in disc form, in particular in the form of CDs and/or DVDs, comprises for the forming of an injection mould (25) a first and a second mirror block (11 and 12, respectively), which lie opposite each other and are movable in relation to each other for opening and closing the mould and also a form ring (20), which concentrically encloses the first mirror block (11) and closes off the injection mould (25) towards the outer edge and is movable in relation to the first mirror block (11), a sliding ring (21; 21a,b,c) for reducing the friction when there is a movement of the form ring (20) in relation to the first mirror block (11) being provided between the first mirror block (11) and the form ring (20) enclosing it. The sliding ring (21; 21a,b,c) is arranged concentrically between the first mirror block (11) and the form ring (20) enclosing it.

Abstract: Disclosed is a stamper assembly for forming an optical data storage disk in a disk molding process. The stamper assembly includes a block element having a first major surface, and a stamper member having a first major surface and an opposite, second major surface. The first major surface of the stamper member is adapted to contact a disk molding material for forming an optical data storage disk in a disk molding process. The stamper assembly further includes a medium for securing the stamper member to the block element, such that substantially the entire second major surface of the stamper member is affixed to the first major surface of the block element. This arrangement prevents relative movement between the stamper member and the block element. This substantially reduces stamper member wear and increases the useful production lifetime of the stamper assembly.

Abstract: A method for fabricating a disc drive load/unload ramp incorporates a disc drive compatible lubricant as the mold releasing agent. A mold having a load/unload ramp cavity is sprayed with a predetermined amount of disc drive compatible lubricant so that the finished load/unload ramp exhibits a predetermined thickness of lubricant. Alternatively, a known amount of disc drive compatible lubricant is combined with the load/unload ramp polymer during the melting stage of the molding process to yield a load/unload ramp exhibiting a predetermined thickness of lubricant. In either case, the lubrication of the load/unload ramp is integrated into the fabrication process in order to obtain a one step finished pre-lubricated product.

Abstract: In the method of manufacturing an optical recording medium according to the present invention, when an optical recording medium having at least first and second minute concave and convex surfaces formed thereon is manufactured, the first and second minute concave and convex surfaces are simultaneously molded on both surfaces of a substrate of the optical recording medium. Therefore, it is possible to manufacture a multilayer optical recording medium having an excellent symmetrical structure with respect to a vertical cross section direction of the substrate, i.e., in the thickness direction of the optical recording medium. Moreover, it is possible to effectively suppress the deformation thereof resulting from curing or shrinkage of an light curing resin or the like, absorption or removal of vapor in the air into or from a substrate, a transparent intermediate film or the like, and so on.

Abstract: A method and apparatus forming a micro-relief pattern on a surface of an optical disc, which micro-relief pattern may form a holographic image in which a shim bearing a micro-relief pattern is pressed onto the surface of the disc and the apparatus used ensures that a greater force is applied to the periphery of the disc and the remainder of the surface on which it is desired to form the micro-relief pattern, such method and apparatus enables a satisfactory relief pattern to be formed over a substantial area of the surface of the disc.

Abstract: A dynamic mold seal for a mold having two relatively movable mold halves is provided. The dynamic mold seal is formed by a sealing ring mounted or secured to a first one of the mold halves. The sealing ring includes a rigid ring portion and a sealing portion including a flexible sealing member for preventing leakage of the pressurized molten material from the mold and thereby preventing the creation of flash about the molded article. The flexible sealing member is preferably formed by a reduced cross section portion of the sealing portion.

Abstract: A stamper protecting layer is interposed between a mold and a stamper of an optical disk molding apparatus, so that forces generated by extension and shrinkage of the stamper in a diametrical direction of the stamper relative to the mold when an optical disk are molded is absorbed by the stamper protecting layer. With this arrangement, the stamper is prevented from being deformed. Accordingly quality and production of the optical disks are improved.

Abstract: A disc substrate molding metal mold apparatus adapted for molding synthetic resin material to carry out molding of disc substrate of an information signal recording medium. This metal mold apparatus is adapted so that smoothing layers of metal are integrally formed on the molding plane surface sides of a first metal mold serving as the fixed side and a second metal mold serving as the movable side which are butted to each other to constitute a molding portion for molding disc substrate, and uneven patterns corresponding to information signals, etc. formed at the disc substrate are directly formed at the metallic layers, thus to carry out molding of disc substrate in which the surface is flattened with high accuracy, and uneven patterns of the metal mold side are transferred without allowing local undulations and/or projections occurring on the disc surface to take place.

Abstract: In a method for controlling the heat transfer in a process for molding an optical disc of the type having a plurality of laser readable depressions of a predetermined quality, the process steps include injecting molten thermoplastic material into a mold having opposing surfaces for replicating respective opposite sides of the disc and imparting optically readable depressions of a predetermined quality to at least one side of said disc, opposing thermally conductive members, and a pair of insulating members, with each insulating member positioned between said conductive mold body and a respective opposing thermally conductive member, maintaining said thermally conductive mold body at a temperature less then about 90 degrees Centigrade wherein said insulting members are selected so that the molten thermoplastic resin is evenly and rapidly cooled from opposing sides to a temperature within about 5 degrees Centigrade of the glass transition temperature of said resin.

Abstract: Improved disc metal mold provides an improved disc without a ring groove thereon. The improved disc metal mold has a fixed metal mold section and a movable metal mold section for forming a cavity therebetween. One of the fixed and movable metal molds has a stamper having an information signal surface on which an information signal is formed in a form of pits, wherein a fused resin is injected into the cavity to form a disc substrate having a center through hole at the center thereof. The disc metal mold includes the stamper having an center hole at a center thereof for retaining the stamper itself and a retainer for retaining the stamper to engage with the center hole of the stamper. The retainer has a slightly larger diameter at a top surface thereof than a diameter of the center hole of the stamper so that the top surface of the retainer is approximately flush with the information signal surface of the stamper by causing the top end thereof to engage with the center hole of the stamper.

Abstract: An optical disk metal mold apparatus includes a fixed cavity plate; a movable cavity plate facing the fixed cavity plate; a disk-shaped plate disposed on at least one of the fixed and movable cavity plates such that it is movable with respect thereto; a stamper plate concentrically supported on the at least one of the fixed and movable cavity plates by the disk-shaped plate such that it is movable with respect to the disk-shaped plate and the at least one of the fixed and movable cavity plates; wherein the stamper plate and the disk-shaped plate are each made of a material and further configured such that a difference between respective deformations of the disk-shaped plate and the stamper plate caused by expansion and contraction thereof due to temperature changes during a molding cycle is smaller than a difference between respective deformations of the stamper plate and the at least one of the fixed and movable cavity plates caused by expansion and contraction thereof due to temperature changes during a mol

Abstract: For extruding an automotive weather strip which includes an elongate major portion and an elongate lip portion which is integrally formed on the major portion, an extruding device is provided, which comprises a material extruder for feeding a first material for the major portion; an additional material extruder for feeding a second material for the lip portion; a fixed shaping die formed with a main extruding opening from which the first material from the material extruder is extruded for formation of the major portion; a movable shaping die formed with an auxiliary extruding opening from which the second material from the additional material extruder is extruded for formation of the lip portion. The movable shaping die is movable relative to the fixed shaping die. The movable shaping die is located in front of the fixed shaping die and spaced from the same by a given distance.

Abstract: A cooling device of an injection mold for an optical disk substrate reduces the chances of cavitation caused by a turbulent flow of passing cooling water, thus enabling a disk cavity plate to be cooled uniformly. A plurality of main arc-shaped passages, which have the same cross-sectional shape and which are concentrically arranged, are provided at a pitch "p" from the inner circumference on the rear surface of the disk cavity plate of the optical disk substrate injection mold. Further provided are a connecting arc-shaped passage having a radius of "p" which connects a first main arc-shaped passage having a radius of R.sub.1 with a second main arc-shaped passage having a radius of R.sub.

Abstract: A process for manufacturing an optical data storage disk stamper includes the steps of providing an amorphous electroless nickel substrate including phosphorous in the amount in a range of about 5 to 15 percent by weight having a toughness of about 100 MPa.sqroot. m, a roughness in a range of about 1 to 50 nm, and a flatness of about 6 .mu.m and depositing a negative photoresist on a surface of the substrate. The substrate has a diameter greater than about 120 mm and a thickness greater than about 300 .mu.m. The negative photoresist then is exposed with a laser to form a negative, data pattern in the photoresist. The photoresist is developed, and the ceramic substrate is ion machined to form the data pattern, in the substrate, such that a spiral track of ridges and lands is formed wherein each ridge has a height of less than about 150 nm. After the data pattern has been ion machined into the substrate, the developed photoresist is stripped from the substrate.

Abstract: This invention provides an optical disk whose recorded information cannot be easily copied to other recording media, with practically no degradation of strength. The optical disk of this invention has a ring-shaped signal layer made of radiation curable resin on a transparent substrate, a reflective layer formed on this signal layer, and a protective layer formed on this reflective layer; moreover, the above mentioned signal layer has a peel strength against the above mentioned transparent substrate in the range of about 20/100 to about 80/100 according to the JIS-K5400 test method; and if the outer and inner diameters of the mentioned signal layer are represented by Os and Is respectively, the outer and inner diameters of the mentioned reflective layer are represented by Or and Ir respectively, and the outer and inner diameters of the mentioned protective layer are represented by Op and Ip respectively, these diameters satisfy the relationships,Os<Or<OpandIp<Ir<Is.

Abstract: An apparatus for holding a stamper plate in a molding metal die is provided which comprises a cavity plate having a cavity center hole, a stamper plate press member having a flange portion larger than the stamper plate center hole, a vacuum evacuation device, a compressed air supply device, a first connecting device for connecting the cavity center hole to the vacuum evacuation device, and a second connecting device for connecting the cavity center hole to the compressed air supply device. The stamper plate is mounted by inserting the stamper plate press member within the cavity center hole and the stamper plate center hole, such that the flange portion is engaged on the upper surface of the stamper plate and a space is formed between the stamper plate press member and the cavity center hole. The vacuum evacuation device is then connected to the cavity center hole through the first connecting device, so that the stamper plate press member is sucked into the cavity center hole.

Abstract: An apparatus for guiding and aligning fixed side and movable side disk cavity plates of disk injection molding dies of an injection molding device is provided with a plurality of first grooves formed on the outer surface of the fixed side disk cavity plate and a plurality of second grooves formed on the outer surface of the movable side disk cavity plate, wherein each of the first grooves and second grooves form a pair of aligned grooves parallel to the center axes of the fixed and movable side disk cavity plates. The apparatus further comprises a plurality of guide blocks fixed to one groove of a pair of aligned grooves and engaged with the other groove of the pair.

Abstract: A mold for molding a substrate of a disk, including a stationary and a movable mold half which are movable relatively to each other, a positioning ring portion on the movable mold half, for positioning an annular stamper at its center hole, and an ejector sleeve located radially inwardly of the positioning ring portion and movable to remove the substrate from the movable mold half. The ejector sleeve includes a recessing end portion which extends in an axial direction thereof beyond an end face of the positioning ring portion into the mold cavity when the stationary and movable mold halves are placed in the closed position. The recessing end portion has an outer circumferential surface which is perpendicular to the end face of the positioning ring portion, so that an annular recess partly defined by a circumferential shoulder surface is formed by the recessing end portion of the ejector sleeve. The circumferential shoulder surface is formed by the outer circumferential surface of the recessing end portion.

Abstract: A process for producing high-density thin type optical disk substrates having good replicability and birefringence sufficient for practical use. In filling the resin into the cavity, the stress on the resin is reduced by controlling the relation of the cavity width and the injection compression force to reduce birefringence. Further, the mirror surface of the mold is maintained at a certain temperature to facilitate the resin flow and a good replicability and reduction of birefringence is achieved by terminating the resin filling and starting the compression process at the time at which the pressure of the resin filling is at a minimum.

Abstract: A disc molding die includes a stationary-side mirror block disposed on a stationary die, a movable-side mirror block disposed on a movable die and facing the stationary-side mirror block so as to define a cavity in combination with the stationary-side mirror block, and a cavity ring disposed on the radially outer side of one of the stationary-side mirror block and the movable-side mirror block so as to define the outer circumferential edge of each disc substrate. The portion of the cavity ring facing the cavity is roughened. When resin is charged into a cavity, very small spaces are formed between the resin and the inner circumferential surface of the cavity ring, due to the roughened portion of the cavity ring facing the cavity. Therefore, the release resistance during die opening or releasing can be decreased.

Abstract: A novel and improved metal mold for molding a runnerless product can be provided. The metal mold according to the present invention comprises a stationary and a movable mold halves, one of which is provided at the center thereof with a recess and the other of which is provided with a compression core to be retractably received by said recess, said stationary and movable mold halves defining a cavity for the runnerless product, and further comprises a hot nozzle inserted into the recess or the compression core and having a tip projecting therefrom to allow resin to be left around the nozzle. In such a construction, a runner section and a gate are defined by said recess and the compression core so as that they are closable by the movement of said compression core, and thereby the center of the final product, e.g. a disc can certainly be finished without punching, cutting or the like.