Abstract: Methods of forming composite block briquettes of prefabricated thinsets, grouts, and self-leveling underlayment products having high sand content, and the resultant composite block briquettes. Processing conditions within a compacting tool are controlled to generate a press force that is applied to a prefabricated cementitious product having a high sand content, whereby the press force enables formation of sustainable prefabricated product briquettes having a high sand content. The controlled compacting processing conditions and parameters of the invention generate usable briquettes that break up and form the intended resultant product of the starting prefabricated cementitious product.

Abstract: Gypsum panels, sheathing systems, and methods of making and using the same are provided. A gypsum panel includes a gypsum core associated with a first fiberglass mat having a continuous barrier coating, the coating penetrating a portion of the first fiberglass mat opposite the gypsum core, wherein gypsum penetrates a remaining fibrous portion of the first fiberglass mat such that voids in the first fiberglass mat are substantially eliminated. A building sheathing system includes at least two gypsum panels and a seaming component to provide a seam at an interface between the gypsum panels.

Abstract: A cementitious protective coating material including a mixture of water, one or more of silicon dioxide/sodium silica pozzolans, anhydrous or hydrous sodium or potassium metasilicate; a rheology enhancing admixture; sodium tetraborate, sodium citrate dihydrate, citric acid, or boric acid; and a micro-fiber.

Abstract: A foreign substance analysis system capable of accurately and easily analyzing a foreign substance contained in a sample. The foreign substance analysis system includes an infrared spectrum acquisition step of acquiring infrared spectrum information of a sample measured by an infrared spectrophotometer; and a fluorescent X-ray spectrum acquisition step of acquiring fluorescent X-ray spectrum information of the sample measured by a fluorescent X-ray analyzer; and a determination step of determining whether or not an organic element is contained in the sample by comparing a ratio of an intensity of a Compton scattered ray and an intensity of a Rayleigh scattered ray in the fluorescent X-ray spectrum information with a set threshold value.

Abstract: An electroconductive paste that includes an inorganic filler which contains a spherical Cu powder of 3 ?m or less in average particle size; a flat Cu powder of 3 or more in aspect ratio and 10 ?m or more in average particle size; glass frit; and a spherical inorganic powder of 30 ?m or more in average particle size, the spherical inorganic powder including an inorganic material that is not melted in a heat treatment step for baking. The spherical inorganic powder is contained in a proportion of 10 to 35 parts by volume with respect to 100 parts by volume of a mixture of the spherical Cu powder and the flat Cu powder. In addition, the proportion of the flat Cu powder falls within the range of 10 to 50% by volume with respect to the total amount of the spherical Cu powder and flat Cu powder.

Abstract: An electrode for a lithium secondary battery, the electrode including: an electrode active material; and a composite including a clay and a polymer intercalated between layers of the clay, a method of manufacturing the electrode, and a lithium secondary battery including the electrode.

Abstract: The present invention provides a composite magnetic sheet having a high magnetic permeability, to be produced easily at a low cost. The composite magnetic sheet includes magnetic substance powders and polytetrafluoroethylene powders.

Abstract: There is provided a method of producing a polycrystalline transparent ceramic substrate used in a transparent substrate or the like for a liquid crystal projector. The method of producing a polycrystalline transparent ceramic substrate is characterized in comprising a step for sintering a ceramic body molded into a predetermined shape and producing a polycrystalline transparent ceramic sintered body, a step for cutting the polycrystalline transparent ceramic sintered body and producing a plurality of polycrystalline transparent ceramic cut bodies, a step for polishing the cut surfaces of the polycrystalline transparent ceramic cut bodies and producing polycrystalline transparent ceramic polished bodies, and a step for applying an antireflection coating to the polycrystalline transparent ceramic polished bodies and producing coated polycrystalline transparent ceramic bodies.

Abstract: Described herein is a monolithic cementitious article with one or more pre-formed shaped regions. The shaped regions are generally channels that extend through a portion of the article or span the full article. The article includes one or more openings at least one of its ends. The article has a low apparent density with a high strength as well as high performance characteristics. The article when manufactured is suitable for use as a building product, such as siding, panel, trim, fascia, roofing, crown moulding, decking, and fencing.

Abstract: The present application is related to substrates having light transmitting areas and light shielding areas. The application discloses methods of manufacturing the substrates, including modifying a light shielding layer be contact to a structured surface.

Abstract: A plant and method for the manufacture of cementitious products, viz. cast concrete roof tiles (T), the plant comprising a mixing station (2) where the constituents of a cementitious composition, less an air entraining agent, are admixed under t atmospheric pressure and further mixed under a partial vacuum of 200 to 340 mBar after the addition of an air entraining agent, the plant also comprising a moulding station (4) where the tiles (T) are cast in a gang-mould (6) before being cured in a conventional autoclave for up to 10 hours at 45 degrees C. The cured concrete roof tiles (T) are de-moulded after curing and conveyed to a surface preparation zone (12) where a primer coat of a water based epoxy and a surface coating of a water based emulsion paint are applied to at least an upper surface in use of the cast concrete roof tiles (T). The admixed cementitious composition has a Ford Cup flow of between 40 and 60 seconds and a slump test of between 180 and 220 mm.

Abstract: A form-work support arrangement for building form-work for moulding a concrete construction panel on top of a previously poured concrete panel (58). Generally the upper panel to be moulded has the same horizontal dimensions as the previously poured panel (58), the arrangement including an anchor bracket (60) adapted to be removably attached (66) to the previously poured concrete panel (58), an edge form bracket (48) adapted to be removably attached (16) to the anchor bracket (60), the edge from bracket (48) adapted to removably support an edge form (18) having an outer face, the outer face defining an edge of the concrete panel to be poured and positioned so that the outer face is generally above the edge of the previously poured concrete panel (58).

Abstract: The present invention relates to methods for forming textured surfaces in a polymeric surfaces. Moreover, the present invention relates to methods for forming textured surfaces in a polymeric surfaces and faithfully replicating the textured surfaces in the surfaces of sol-gel films on the surfaces of very hard materials, e.g., of glass, ceramic, or glass-ceramic substrates.

Abstract: Compositions and methods for manufacturing sheets having a highly inorganically filled matrix. Suitable inorganically filled mixtures are prepared by mixing together an organic polymer binder, water, one or more inorganic aggregate materials, fibers, and optional admixtures in the correct proportions in order to form a sheet which has the desired performance criteria. The inorganically filled mixtures are formed into sheets by first extruding the mixtures and the passing the extruded materials between a set of rollers. The rolled sheets are dried in an accelerated manner to form a substantially hardened sheet, such as by heated rollers and/or a drying chamber. The inorganically filled sheets may have properties substantially similar to sheets presently made from traditional materials like paper, cardboard, polystyrene, plastic, or metal. Such sheets can be rolled, pressed, scored, perforated, folded, and glued.

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 mold for injection molding thin discs for DVD has a cavity (C) bounded by a information-bearing stamper (29) surface, a mirror plate (31) opposite to the stamper surface, and the tip (33s) of an inserting block (33) at a central opening in the mirror plate. The tip surface (33s) protrudes into the cavity past the surface of the mirror plate between 10 .mu.m and 70 .mu.m. The mirror plate molding surface is slightly frusto-conical, with a gradient Y/R gradually increasing the depth of the cavity toward the periphery. R is approximately 40 mm and Y lies in the range of 5 .mu.m and 30 .mu.m. The mirror plate is preferably manufactured flat on the surface facing the mold, but bolted down onto a frusto-conical backing plate or on top of a central ring, so that it is stressed into the desired shallow cone shape. The invention includes a method of injecting resin with lower clamping force of about 2 tons and then applying a higher force of about 17 tons.

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 method for molding an optical disk comprises: applying a thermally insulative insert coating to at least one thermally insulative mold insert to provide at least one coated mold insert having a reduced surface roughness; positioning the coated mold insert between a thermally conductive mold form and a portion of a thermally conductive mold apparatus; injecting a molten thermoplastic material into the mold apparatus; retaining the material in the mold apparatus for a time sufficient for the molten thermoplastic material to cool below its glass transition temperature to form the optical disk; and ejecting the optical disk from the mold apparatus. In another embodiment, the mold insert is coated or laminated on the mold form with the mold insert having a coefficient of thermal expansion compatible with the coefficient of thermal expansion of the mold form. In another embodiment, the mold insert is fabricated by being applied, cured, and then removed from a release layer.

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 magnetic recording medium having a substrate disc with microscopic bumps formed by focusing a laser beam, wherein spacings D between adjacent bumps in the circumferential direction of the disc are varied so that formula (1) is satisfied:1.ltoreq.[(D.sub.max -D.sub.min)/D.sub.avg ].times.100(%).ltoreq.200(1)wherein D.sub.max, D.sub.min and D.sub.avg are the maximum, minimum and average spacings, respectively, as determined by a method wherein 2.5% of the total number of spacings D, having the largest dimensions, and 2.5% of the total number of spacings D, having the smallest dimensions, are excluded; and D.sub.max, D.sub.min and D.sub.avg are measured on the remaining 95% of the total number of spacings D. The variation of bump spacings is attained, for example, by (i) modulating the pulse repetition frequency F of laser beam so that the ratio of "(F.sub.max -F.sub.min)/F.sub.avg " is maintained within the range of 0.01 to 100, wherein F.sub.max, F.sub.min and F.sub.

Abstract: A method and apparatus are provided for improving the durability of lubricating layers on the surfaces of disks. The lubricating layers on the disks are exposed to ultraviolet and infrared radiation of sufficient duration and energy to reduce the total thickness of the layer but retain at least about 40% of the thickness of the remaining layer in bonded form. The useable lifetime of the lubricating surface is prolonged by treatment of the lubricating layer in this manner.

Abstract: An improved method and means for eliminating scratches and other mechanical surface damage from plastic surfaces. The method consists in applying a liquid of suitable composition to the surface of a plastic object, allowing in a short period of time for the solvent to soften the plastic substrate, and removing the liquid by draining and evaporation. No abrasive, filler or polishing compunds are required. Suitable liquids include those comprising a solvent for the plastic and a non-solvent diluent and a small quantity of surfactant.

Abstract: A removable plastic film is attached to the mold die whenever the mold dies needs to be cleaned. Using such a film, the problems with cleaning the mold dies are avoided because whenever the mold dies need cleaning, the film may simply be placed over the mold and simply peeled off to remove all contaminants from the mold. The contaminants stick to the peeled off film and so are removed from the mold.

Abstract: A method is provided for manufacturing a diamond-like carbon (DLC) coated optical phase-change recording medium for use with near-field optical head devices and which exhibits superior wear resistance and improved lifetime. According to the method, the surface of a composite optical phase-change media structure deposited onto a substrate is subjected to ion beam deposition of a DLC over-coat to a thickness of no greater than about 450 .ANG.. Preferably the DLC is ion beam deposited onto the phase-change recording layer at the surface of the medium structure or onto a germanium-containing adhesion-promoting interlayer to achieve the desired adhesion of the DLC to the surface of the medium structure.

Abstract: When applying a coating film by a spin coating method on a disc-shaped recording medium, the film thickness difference between the inner rim and the outer rim of the disc has to be suppressed. To this end, a coating liquid is supplied to a center portion of the disc-shaped recording medium and a rotary disc, as a center shaft of a rotary disc is inserted into a recess formed in a turntable on which the disc-shaped recording medium is set and the disc-shaped recording medium and a rotary disc are run in rotation. The coating liquid is spread under the centrifugal force caused by rotation for forming a coating film on the disc-shaped recording medium.

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: The present invention relates to a polycarbonate molding material for optical discs, comprising pellets which comprises a polycarbonate with a viscosity-average molecular weight of 10,000 to 18,000;has an average length of 2.5 to 3.5 mm; andhas an average longer diameter of the sectional ellipse of 2.60 to 3.2 mm,not less than 70% of said pellets having a length falling within the range of .+-.0.08 mm from the mean value of length and a longer diameter falling within the range of .+-.0.12 mm from the mean value of longer diameter.

Abstract: An optical memory device and a method for manufacturing thereof. An optical memory device has at least one data layer formed on a substrate. An upper surface of the substrate is formed with a pattern comprising a plurality of regions which are capable of obtaining, when covered by a recording medium, desired optical properties different from those of the substrate. The patterned surface of the substrate is coated with the recording medium. The recording medium is removed from the patterned surface after the recording regions have obtained the desired optical properties.

Abstract: Optical disc stampers, methods of manufacturing the optical disc stampers, systems for manufacturing the optical disc stampers, and methods of replicating optical discs using the stampers are disclosed. The optical disc stamper is formed directly on a substrate that supports a patterning material including at least one layer of a first material and at least one layer of a second material. The first and second materials can include a metal and semiconductor. The patterning material is exposed to energy in selected areas. Unexposed areas of the patterning material are then removed, resulting in an optical disc stamper. The first and second materials can form an amorphous alloy in the exposed selected areas that remains after removal of the unexposed patterning material. The optical disc stamper can be used in the replication of optical data storage discs. Also disclosed arc systems for practicing the methods to produce optical data storage disc stampers.

Abstract: Various configurations of a directed energy assisted micro embossing machine/station in a vacuum chamber utilized in a continuous manufacturing process and the web structure products made by that process (optical disks, cards, tapes, holographic reflectors, diffusers, binary optical elements, etc.) are disclosed. The configurations can include a single machine roll to roll system for embossing optical features on the surface of a single substrate and applying appropriate metallic, dielectric, semiconductor, polymer and other coatings all in a vacuum chamber.

Abstract: Method and apparatus for a disk texturing operation in which laser pulses are successively bombarded against a delimited surface area on the face of a rotating disk, from an optical laser pulse irradiating means which is put in movement in a radial direction relative to the disk to provide a textured zone of a predetermined width on the disk. A pulsed laser beam from a laser light source is adjusted to an optimum power level for an aimed bump diameter. The laser beam is then transformed into an annular beam of a collimated light flux having specified inner and outer diameters, and the resulting laser pulses are successively bombarded on the texturing zone through an objective optical system condensing said laser pulses into a specified spot diameter thereby to form minute bumps of predetermined shape and diameter uniformly on the surface of the disk.

Abstract: A method of releasing thin discs during molding forms discs with a central aperture with a thin gate connecting the molded disc to a sprue. A male cutter advances under pressure control of an actuator operating the male cutter and implements releasing of the molded discs from the surfaces of a stamper and a mirror plate during mold closing. The molded disc and the sprue are ejected by a center pin in the mold opening operation.

Abstract: A disc is provided which includes a disc body of disc shape having a center hole. An information recording area is formed on one side surface of the disc body. The information recording area has information thereon read by reflection of laser light. The information recording area has an inner circumferential edge positioned adjacent to the center hole. The disc body has a radius ranging from 39 mm to 80 mm, the center hole has a radius ranging from 7.5 mm to 7.55 mm, and the inner circumferential edge of the information recording area being positioned to extend from a radius of 15 mm to 22 mm from the center of the disc body.

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 a half of a clamp region for clamping the optical information medium is filled with the resin.

Abstract: A method of making irregular shaped playing discs to achieve proper balance for playing involves the use of a grid (7) divided into quadrants (1, 2, 3, 4) having squares of a predetermined size. A template (8) is placed on the grid (7) into which a desired artwork (9) is fitted. The artwork may include face of a recording star, holiday character or other desired item. The artwork (9) must be placed within the template (8) so that an equal number of squares is taken from each quadrant (1, 2, 3, 4) of the grid (7) within the template (8). Once the shape of the artwork is determined, the recording medium, whether it be audio, visual or a combination of both, is applied. The visual appearance of the artwork (9) may then be silk screened or otherwise applied to the disc. Once the above method is accomplished, the disc can be used as a master for making a mold to premold other discs or each disc may be cut around the perimeter of the artwork to result in discs in the shape of the artwork.

Abstract: A method for the replication of diffractive optical elements using audio/video disc manufacturing equipment and processes. The audio/video disc manufacturing process and mold mastering tooling create diffractive optical elements using a mold plate. The diffractive optic design and photomasks are first fabricated then replicated using compact disc industry mold mastering techniques. The surface relief pattern is produced centered in the plate using ion milling or refractive ion etching photolithographic fabrication techniques. Once patterned, the mold master plate is punched into a circular form consistent with standard compact or video disc mold bases--typically eight inches for a compact disc. After molding, each element can be cut out of the disc using blade, shear, waterjet or laser cutting.

Abstract: A prescribed molded substrate is molded out of a melted resin with a stamper having projections for forming pits with the shape of the projections preliminarily set to be greater than the shape of pits of the substrate to be molded. The relationship between the height H of the projections for forming the pits to the stamper and the depth d of the molded substrate is such that H/d=1.3 to 1.8.

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: In a technique for bonding two disc-shaped resin substrates constituting the storage disc, the disc-shaped resin substrates are centered to correct the nonalignment therebetween. The method includes steps of placing disc-shaped resin substrates, which have central holes and adhesive interposed therebetween, on a centering holding table provided with a boss, spreading the boss inserted into the central holes of the disc-shaped resin substrates outwardly to center the disc-shaped resin substrates, and partially irradiating the adhesive interposed between the disc-shaped resin substrates with UV rays for curing the disc-shaped resin substrates in the vicinity of the centers thereof to temporarily fix the disc-shaped resin substrates. The nonalignment between the disc-shaped resin substrates is corrected, thereby increasing the quality of the storage disc.

Abstract: An apparatus and method for manufacturing compact discs (2) having a non-circular outer profile (8) includes imprinting digital information in an annular region (12) on the under face of a compact disc blank (36) such that an outer limit (14) of the annular region (12) does not extend beyond the innermost reach (16) of the edge of the compact disc (2) in its final shape, forming a first alignment mark (20a, 20b) on the blank (36), applying a label (22) to the upper face of the blank (36), orienting the blank (36) on a manufacturing platform (26) by aligning the first alignment mark (20a, 20b) with respect to an alignment mark (34a, 34b) on the manufacturing platform (26), securing the blank (36) against rotation with respect to the platform (26) and shaping the blank (36) into its final shape by removing portions of the blank with a grinding tool (44) which cooperates with a form (38) to provide the final shape.

Abstract: An apparatus for exposing an optical master disk includes an exposure section, an exposure control section, a guide groove exposure voltage supplier and a modulator. The exposure section is for exposing a guide groove and pre-pits by different laser beams, and the exposure control section is for controlling an exposure voltage of the laser beams in the exposure section and an exposure timing. The guide groove exposure voltage supplier is for supplying, in accordance with the pre-pit designation signal, to the exposure section a guide groove exposure voltage of a first power level when an inside or an outside guide groove adjacent to the pre-pits is exposed and a guide groove exposure voltage of a second power level when a guide groove not adjacent to the pre-pits is exposed. The modulator modulates a laser beam for exposing the guide groove in accordance with the guide groove exposure voltage.

Abstract: A laser beam is focused onto a substrate for texturing the substrate surface to form a multiplicity of microscopic bumps thereon, wherein the laser beam to be focused is continuously modulated at an I.sub.max /I.sub.min ratio in the range from 10 to 100 wherein I.sub.max is the maximum amplitude of pulse oscillating laser beam output and I.sub.min is the minimum amplitude of pulse oscillating laser beam output, while the minimum output of the laser beam is controlled to a level lower than the minimum energy required for creating the microscopic bumps. A magnetic recording medium having good CSS characteristics can be produced at a high production rate from the laser-textured substrate.

Abstract: A method of making a cast concrete stepping stone whose exposed upper surface has the appearance of two or more grouted attractive natural stepping stones. A liquid release agent is applied to the mold which is then placed on a vibrator table and filled with wet concrete. The mold is vibrated for about 30 seconds and the surface of the concrete troweled smooth. Dry body color is sprinkled over the concrete surface and troweled to completely cover the concrete. A dry release agent containing powdered color having a darker shade than the body color is sprinkled over the dry body color covering the concrete. The desired pattern is then pressed into the surface of the concrete and after a six hour drying time, the cast stepping stone is removed from the mold. Excess body color and release agent are washed away and the washed surfaces totally dried. Finally a clear concrete sealer is applied to the exposed upper surface of the concrete stepping stone.

Abstract: An optical disc molding device has a pair of molds for injection molding a disc substrate within cavities, and a stamper supported within at least one cavity, for molding a data recording surface in such a manner that the inside diameter side of the stamper supporting surface of the cavity protrudes inwardly in the disc thickness direction from the data recording surface. The flatness of a laminated reference plane has thus been deteriorated by burrs occurring on a disc substrate.

Abstract: It can be selected whether to form a both-side wobble groove whose both side walls wobble by irradiating two light beams while oscillating the same along the radius of a magneto-optical master disk, or to form a one-side wobble groove one of whose side walls alone wobbles by irradiating two light beams while fixing one of the same and oscillating the other along the radius of the magneto-optical master disk. Then, either a single one-side or both-side groove for tracking-use is formed by irradiating both the two light beams on a photo-resist applied on a glass substrate in accordance with address data. As a result, grooves of different types, both-side and one-side grooves, can be formed continuously in the exposing process.

Abstract: A multi-layer optical recording medium manufacturing method and apparatus thereof forms a resin layer having a second recording layer on a first recording layer. The first recording layer includes a reflecting layer and a first recording layer sequentially formed on a transparent substrate. The multi-layer optical recording medium manufacturing apparatus includes an upper and a lower mold on which is respectively fixed the transparent substrate and a stamp such that they are facing each other. Communicating holes formed in the transparent substrate and the stamp are formed in center portions of each of the molds. A punch member capable of vertical movement is established in the communicating hole of the lower mold, and resin supply established in the communicating hole of the upper mold. The above apparatus has the advantage of improving productivity of the manufacture of a multi-layer optical recording medium.

Abstract: Compositions and methods for manufacturing sheets having a starch-bound matrix reinforced with fibers and optionally including an inorganic mineral filler. Suitable mixtures for forming the sheets are prepared by mixing together water, unmodified and ungelatinized starch granules, a cellulosic ether, fibers, and optionally an inorganic mineral filler in the correct proportions to form a sheet having desired properties. The mixtures are formed into sheets by passing them between one or more sets of heated rollers to form green sheets. The heated rollers cause the cellulosic ether to form a skin on the outer surfaces of the sheet that prevents the starch granules from causing the sheet to adhere to the rollers upon gelation of the starch. The green sheets are passed between heated rollers to gelatinize the starch granules, and then to dry the sheet by removing a substantial portion of the water by evaporation.

Abstract: Two disc bases D having different information are molded in a time by a pair of cavities formed when clamping the molds 1 and 2, which are filled with the molten resin by being injected. After taking out the disc bases from the mold by a product taking out apparatus, those are coated with a reflection layer by a sputtering apparatus and subsequently coated with a protection layer by a coating apparatus and finally bonded by a bonding apparatus to obtain a single disc VD. This disc VD can avoid the mechanical troubles such as distortion, bending, twisting or peeling off of the bonded portion in a time lapse after being bonded, because those disc bases VD are molded in a pair of cavities 3, 3 formed in a mold using the material of the same lot, i.e. under the same condition. Representative drawing FIG. 1.

Abstract: A method of manufacturing a die for optical elements having a given construction on a relief type grating or the like is disclosed. The method includes the steps of: forming a workpiece film on a substrate; machining the workpiece film in a required configuration; subjecting the workpiece film machined in the required form and the substrate to etching to transfer the configuration of the workpiece film on the substrate analogously in the depth direction; and forming a die by using the etched substrate as a master matrix.

Abstract: Master disks for providing dies in particular for pressing optical disks, methods of manufacturing same, pressing dies obtained from such master disks and optical disks obtained from the latter and such pressing dies, the master disks consisting of a support carrying at its surface a succession of microcups representative of the information to be duplicated and consisting of a hard, conducting material reflecting in the near infrared range and selected from a zirconium, hafnium or titanium nitride or carbonitride, a hard ceramic reflecting in the near infrared range and conducting at the surface only and a hard glass reflecting in the near infrared range and conducting at the surface only.