Abstract: A method of controlling an oven for producing tooth replacement components. An electric motor moves a piston that acts upon a moldable restoration material. The restoration material is introduced into a muffle oven having an oven hood that can be removed from the muffle. The compactibility curve is established as a function of the type of dental material utilized. Immediately after conclusion of the mold time, the motor is turned off and the oven hood is removed.

Abstract: A disposable plunger for use in a pressing furnace for the fabrication of dental restorations. The plunger is fabricated of a refractory investment material such as gypsum-bonded, phosphate-bonded or ethyl silicate-bonded investment materials. The plunger is fabricated by known casting methods. The mold used for making the plunger can be supplied by a manufacturer of molds or can be easily made by using an alumina or similar plunger as a model. Laborious cleaning and grinding are not required with plungers herein described. Cracking problems that occur with prior art plungers are decreased, if not completely eliminated.

Abstract: A method for manufacturing a fiber rein-forced composite dental restoration comprising the steps of (i) preparing a mould; (ii) filling the cavity of the mould with a fiber-reinforced polymerizable material comprising an organic matrix and a fiber component embedded within the matrix; (iii) applying pressure to the fiber-reinforced polymerizable material; and (iv) curing the fiber-reinforced polymerizable material. The method is characterized in that the mould is designed in a way which allows excess organic matrix material to escape form the cavity during pressing.

Abstract: An apparatus and process for continuously producing composite structural beams is disclosed. The process includes a first step of forming a tubular element from fibers of composite material, a second step of separating the tubular element into longitudinally extensive, circumferentially separated, corner caps, a third step of securing sandwich panels between adjacent corner caps to form a tubular beam, a fourth step of shaping the tubular beam, and a fifth step of curing the shaped tubular beam. Also disclosed is an exemplary beam constructed in accordance with the process of the present invention.

Abstract: A method for making artificial tooth bridges having a ceramic densely sintered high strength individual core veneered with porcelain using powder metallurgical methods, wherein the individual bridge parts are joined together as a bridge core with glass, which in molten condition wets the ceramic core material. The glass therefore finds its way into the gap between the bridge parts and reacts with the ceramics so that during cooling it forms a strong joint between the individual densely sintered ceramic bridge parts.

Abstract: The invention relates to a method for manufacturing a fiber reinforced composite comprising the steps of (i) preparing a mould; (ii) filling the cavity of the mould with a fiber-reinforced polymerizable material comprising an organic matrix and a fiber component embedded within the matrix; (iii) applying pressure to the fiber-reinforced polymerizable material; and (iv) curing the fiber-reinforced polymerizable material. The method is characterized in that the mould is designed in a way which allows excess organic matrix material to escape form the cavity during pressing.

Abstract: A process for producing a ceramic network material including the steps of: introducing a ceramic powder into a mold to form a molded material; firing the molded material to form a ceramic, open pore network; infusing the ceramic network with a silane solution; infusing a monomer to at least a portion of the ceramic network; and forming an interpenetrating network. The ceramic network materials may be used as restorative materials and in various devices such as posts, implant abutments, orthodontic brackets and blocks.

Abstract: A shaped, high-strength dental ceramic prothesis is made by pressing a molding composition comprising about 1-50 wt % glass particles and about 50-99 wt % ceramic particles to form a ceramic frame, veneering the frame and firing the coated frame.

Abstract: A dental porcelain composition, comprising a glassy matrix and leucite crystallites embedded therein, and having maturing temperatures in the range from about 600.degree. C. to about 885.degree. C. and CTEs in the range from about 11 to about 19, more preferably in the range from about 11.5 to about 18, and most preferably in the range from about 12 to about 17.5.times.10.sup.-6 /.degree.C. (measured from 25.degree. C. to 500.degree. C.). The tetragonal leucite is preferably both fine-grained (i.e, having average diameters of less than about 7 microns) and uniformly-sized. Preferably, the average diameters are less than about 1 to about 3 microns.

Abstract: A method of taking dental impressions for various types of dental work which is a two step process with only one tray insertion. The impression materials are selected and have durometer measurements which permit a technique without the use of a retraction cord, and the materials are highly thixotropic providing accurate results with a minimum of patient discomfort.

Abstract: A simple, fast, and reliable method and apparatus are provided for replicating a light shaping surface structure on a laminated surface of a relatively rigid substrate. More specifically, after the substrate is mounted on a table and a layer of epoxy is deposited between the substrate and a submaster to produce a layered structure, the layered structure is automatically compressed in a nip formed between the table and an outer surface of a rotating impression roller, thereby replicating the surface structure in the epoxy layer. The epoxy is then cured, and the submaster is separated from the substrate to leave a laminated structure having the light shaping surface structure on a surface thereof. Preferably, the submaster is wrapped around the impression roller, and the impression roller is rotated while the table is reciprocated linearly to compress the layered structure in the nip.

Abstract: A method for producing a dental prosthesis to be fitted to a fitting member including the steps of: determining the three-dimensional contours of the fitting member; producing a three-dimensional form of the dental prosthesis; producing a working stump and/or a working pack; placing the working stump in the form and/or packing the working pack around the outside of the form to completely cover the form; sintering the form with the working stump and/or the working pack; and separating the working stump and/or the working pack from the dental prosthesis after sintering. The working stump and working pack are produced such that they are enlarged by a predetermined enlargement factor.

Abstract: A method of making embossed optical polymer films and embossed optical polymer films made are described. The embossed optical polymer films have substantially the same optical properties as unembossed optical polymer films. The method includes providing an optical polymer film having first and second major surfaces, softening at least one of the first and second major surfaces to produce a softened surface, embossing the softened surface to produce an embossed optical polymer film, and cooling the embossed optical polymer film.

Abstract: A dental porcelain composition, comprising a glassy matrix and rubidium leucite crystallites embedded therein, and having maturing temperatures in the range from about 650.degree. C. to about 800.degree. C. and CTEs in the range from about 13 to about 17, more preferably in the range from about 13.5 to about 16, and most preferably in the range from about 14 to about 16.times.10.sup.-6 /.degree. C. (measured from 25.degree. C. to 400.degree. C.). The tetragonal rubidium leucite is preferably both fine-grained (i.e., having average diameters of less than about 5 microns) and uniformly sized. Preferably, the average diameters are less than about 1 to about 2 microns.

Abstract: A method of using latex as a protective separator and release agent between a resin on-lay, in-lay, laminate, or other restorations, and a dental model or tooth to be restored includes the steps of applying the latex to a surface of the dental model preparation by substantially covering the surface area that is to contact and form the restoration, to prevent direct contact of thereto and with the dental model or tooth, while facilitating a mutual release of the elements after curing has occurred. The latex is in the form of an emulsion of about forty to about seventy percent of solids, the solids including a protein material within a water base in which such latex is primarily isoprene butyryl and about 0.04% to about 0.5% percent ammonium hydroxide, to a restoration-forming surface of a dental model of tooth preparation covering that area which is in contact with the resin or other material on-lay or in-lay designed for such fabrication.

Abstract: A lenticular pattern forming roll, used for forming a lenticular screen, includes a chill roll and a lenticular sleeve positioned on the chill roll. The lenticular sleeve has a lenticular pattern formed on an outer surface for forming a corresponding lenticular pattern in a plastic sheet. The sleeve may be readily manufactured and transported to a desired location to be installed on the chill roll. The lenticular pattern forming roll may be readily used in combination with an extruder for extruding a hot plastic sheet to form the lenticular screen. The sleeve may also be removed from the chill roll and transported for resurfacing and without requiring transporting of the chill roll. The lenticular sleeve may preferably comprise a nickel-phosphorous composition defining at least a radially outermost portion of the sleeve in which the lenticular pattern is formed.

Abstract: The invention concerns a process for the production of a frame for inlays, crowns and bridges in dental techniques. By means of the process, a considerable reduction in work and time expenditure is achieved in comparison with known processes. In the case of this process, frames of spinel, alumina, zirconia, metal powder or similar materials are produced in that a) a shrink foil is drawn on the stump or the stumps of a working model; b) the draw-non shrink foil is provided with a slip; and c) the shrink foil and the slip present on the shrink foil are removed from the working model and calcined to burn off the shrink foil.

Abstract: An object of the present invention is to provide a process for producing a lens sheet, which is safe, which can cut the material cost and the facility cost, which can continuously produce, by the use of a forming die, a formed lens sheet that contains no air bubbles in the lens area thereof and which can attain higher productivity, and reduction of costs by using a decreased number of forming dies or the like; and a projection screen. The process for producing a lens sheet according to the present invention includes the steps of coating a resin composition for a lens sheet onto a forming die by the use of a multiple nozzle in which a plurality of nozzles are arranged at intervals along the forming die for a lens sheet in a direction substantially rectangular to a direction in which the resin composition for a lens sheet will be coated, and superposing a base material on the resin composition for a lens sheet which has been coated onto the forming die.

Abstract: A polishing roll, used for forming a smooth plastic sheet, includes a chill roll and a polishing sleeve positioned on the chill roll. The polishing sleeve has a polished outer surface for forming a corresponding smooth surface in a plastic sheet. The sleeve may be readily manufactured and transported to a desired location to be installed on the chill roll. The polishing roll may be readily used in combination with an extruder for extruding a hot plastic sheet to form the smooth plastic sheet. The sleeve may also be removed from the chill roll and transported for resurfacing and without requiring transporting of the chill roll. The sleeve may preferably comprise a nickel-phosphorous composition defining at least a radially outermost portion of the sleeve in which the polished surface is formed.

Abstract: A device including an injection molding tool for use once or a few times for producing a sinterable ceramic and/or metallic product. The device includes at least one first tool part. At least one second tool part is combinable with the at least one first tool part to form a molding space for the product. The second tool part is produced using a wet composition and is made of a readily worked and form-stable material containing pores and admixed heat-conducting particles. A wet composition-enclosing member can engage the first tool part during the production of the second tool part. A unit can be connected to the at least one second tool part and can be arranged with the at least one first tool part for absorbing internal lateral displacement forces arising during squeezing or injection of an injection molding composition.

Abstract: Shaped article replicas which are proportionately accurate replicas of a shaped article and which are equal, greater or smaller in size than said shaped article are made by preparing a swellable polymer replica of said shaped article; immersing said swellable polymer replica in a swelling agent system under conditions which will enlarge said polymer replica to a predetermined extent; forming a casting mold of such enlarged polymer replica; making a powder compact in said casting mold and heating said powder compact to produced a proportionately accurate solid replica of a predetermined size.

Abstract: A method and apparatus for producing a lenticular plastic sheet from a plastic sheet having a first surface and an opposite second surface employs a first chill roller having an outer surface, a patterned chill roller having an outer surface defining a first lenticular pattern thereon, disposed adjacent and parallel to the first chill roller so as to define a first nip therebetween and a second chill roller, having an outer surface and being spaced apart from the first chill roller and disposed adjacent and parallel to the patterned chill roller so as to form a second nip therebetween. A plastic sheet is extruded into the first nip so that the plastic sheet is molten as it passes into the first nip and so that the first surface of the plastic sheet is in contact with the first lenticular pattern, thereby facilitating the formation of a second lenticular pattern on the first surface. The second lenticular pattern is complimentary in shape to the first lenticular pattern.

Abstract: A method and apparatus for molding an illumination device using an open mold are provided which allow for the addition of light extraction structures to a prefabricated light guide using a curable material. A mold containing the extraction structures is first provided. Curable molding material and the prefabricated light guide are placed into the mold, and an overlay comprising light extraction structures is cured onto the light guide, providing a functional illumination device.

Abstract: An impression composition which is based on an aziridine-free composition which can be vulcanized at room temperature, and which comprises wax is provided according to the invention. The wax increases the dimensional stability of the composition during mixing and curing. The invention furthermore provides a kit for the preparation of such compositions and a process for the preparation of the wax-containing components of these kits. The wax is dispersed throughout the composition and is prepared by shock-cooling. The wax forms a crystalline network.

Abstract: An embossed substrate comprising a substrate of a plastic material and having a surface and an embossed surface carried by the surface of the substrate. The embossed surface is characterized by having a pattern with an average roughness of between 100 nanometers and 300 nanometers with the roughness being distributed substantially uniformly over the surface, the pattern has ridges and valleys with the horizontal distance between adjacent ridges and/or valleys being greater than the depth between the ridges and the valleys. The peaks and the valleys are randomly disposed without periodicity to cause diffusion of light impinging thereon to minimize or eliminate interference effects when the embossed surface overcoated with thin planar organic layers is exposed to light.

Abstract: A method for making multilayer optical films is provided in which the degradation of the optical extinction of the thinnest optical layers is avoided by casting these layers close to the casting wheel.

Abstract: Provided is a method for manufacturing a thermoplastic resin sheet bearing an embossed pattern, which employs a manufacturing apparatus having a first roll having an elastic material coated surface, a mirror-faced metal, endless belt, which is wound around the first roll and a second roll, and a third roll so provided that the metal, endless belt is wrapped partially around the third roll, which contacts the first roll via the metal, endless belt and which has an embossed pattern formed on one surface. According to this method, the thermoplastic resin sheet, partially melted, is fed between the metal, endless belt, which contacts the first roll, and the third roll. The elastic member is elastically deformed by application of a pressing force between the first and the third roll, while face pressure welding the thermoplastic sheet by using the first and the third rolls to transfer the embossed pattern and to cool the thermoplastic resin sheet. A surface temperature for the third roll of from 0.degree. C.

Abstract: Improved very high viscosity (putty) two component polymerizable polyorganosiloxane composition for use in making dental impressions, having improved tear strength, handling and wettability. Improved tear strength results from inclusion of a quadri-functional polysiloxane having a vinyl content of 0.16 to 0.24 m-mole/g. Working time is maintained by including sufficient amounts of a retarder composition that delays onset of the vinyl polymerization. Handling is improved by the addition of a very high viscosity linear vinyl terminated polydimethylsiloxane which reduces tackiness and improves the shelf stability. Wettability is improved by including a surfactant resulting in a surface contact angle with water at three minutes of less than 50.degree.. The surfactant chosen has an HLB of 8-11, such that the wetting contact angle is achieved within less than two minutes and remains wetting throughout the working time of the impression taking, substantially improving the impression making process.

Abstract: A living tissue replacement of crystallized glass having bioaffinity and mechanical strength is briefly obtained simply by pressure molding or machining without using a special equipment. A glass material having a softening point below its crystallization temperature and exhibiting viscous flow at temperatures below its melting point is heated at a temperature above its Tg and pressed at the temperature to mold to a desired shape, thereby manufacturing a living tissue replacement such as a dental crown. Molding can be done under a pressure of up to 20 MPa.

Abstract: This invention provides a method for continuously forming an array of optical elements which includes feeding synthetic resin sheeting having a temperature in the flow temperature region of the synthetic resin directly to a thermoforming zone of embossing means; continuously pressing the sheeting against a mold provided on the embossing means and having a pattern for defining an array of optical elements while maintaining the sheeting at that flow temperature, to bring the sheeting into intimate contact with the mold and thereby form an array of optical elements on one surface of the sheeting; laminating a surfacing film to the side of the sheeting opposite to the mold as required; feeding a carrier film to the side of the resulting laminate opposite to the mold and bringing the carrier film into close contact therewith; and cooling the sheeting to a temperature lower than the glass transition temperature of the synthetic resin, as well as apparatus therefor.

Abstract: A blank for preparing artificial tooth parts, such as inlays, overlays or partial and complete crowns and bridges comprises a body of laminate material. The body has at least one layer of high abrasive resistance, at least one layer of high breaking strength, and at least one layer of lower hardness and breaking strength. For forming the tooth part, material is removed from the blank in such a way that the layer having high fracture strength forms a reinforcing structure. In a single working step, a tooth part of high strength can be machined.

Abstract: A method of making an optical fiber device, which comprises the steps of providing an optical fiber element comprising an optical fiber having at least one thermally removable coating thereon, and thermally removing all or a predetermined portion of the thermally removable coating(s) to sufficiently expose said optical fiber for a subsequent processing step. Following removal of the thermally removable coating, the optical fiber has a predetermined median fracture stress, as measured according to FOTP-28. The optical fiber may then be processed into an optical fiber device and optionally recoated.

Abstract: The present invention provides a method and apparatus for impressing a diffraction image into an oriented polymeric film wherein, after orientation of the film, the temperature of the film is raised to a desired annealing temperature, the film temperature being continuously maintained above room temperature while a diffraction pattern is embossed directly into the surface of the film.

Abstract: A process for producing a light diffusing sheet material, and materials made therefrom. A dispersion of light scattering optically clear particles in an optically clear matrix during mixing of the constituent components of the diffuser in the liquid phase and then forming a film or sheet by, e.g., extrusion or casting, from which a screen suitable for displaying images projected thereupon may be constructed. The respective light dispersing and matrix components are chosen by their respective viscosities, interfacial surface energies, and refractive index differential. In an embodiment, it has been found that when the viscosity ratio of first (matrix) optically clear material to second (light dispersing) optically clear is between 0.05 and 10, the first optically clear material disperses or breaks the second optically clear material up into particles of a desired diameter during mixing or mastication of the two optically clear materials while in the fluid phase.

Abstract: Acrylic light pipe as described in Bigley et al., U.S. Pat. Nos. 5,406,641 and 5,485,541, has adequate thermal stability for many purposes. It has been found that improved thermal stability, as reflected in color formation, can be imparted by adjusting the polymerization conditions to produce the uncured core polymer of the core/clad construction with a much reduced terminal vinyl content, preferably below 0.5 vinyl groups/1000 monomer units.

Abstract: A process for manufacturing a non-metallic dental prosthesis including a ceramic frame and an esthetic ceramic veneer including the steps of: preparing the ceramic frame by press molding a composition comprising from 1 to 50 parts by weight glass particles and from 50 to 99 parts by weight ceramic particles at a molding temperature from 800 to 1300.degree. C.; applying a slurry comprising a dental ceramic veneering composition to the thus prepared ceramic frame; and firing the ceramic frame having the slurry applied thereto at a temperature lower than the molding temperature to produce said dental prosthesis. The dental ceramic veneering composition may have a melting point at least 50.degree. C. less than the molding temperature.

Abstract: A process for manufacturing dental prosthetics based on ceramics including the following steps:machine-processing a prefabricated shaped body to form a molded body with the patient's situation being considered, said prefabricated shaped body consisting of at least one oxide-ceramic material selected from the group consisting of aluminum oxide, magnesium oxide, zirconium oxide, and titanium oxide and minor amounts of siliceous additives;compacting the thus obtained molded body; andoptionally jacketing the compacted molded body.

Abstract: A continuous sheet having an optical function imparted thereto, which is obtained by extruding a thermoplastic resin on a three-dimensional pattern side of a continuous release sheet having a three-dimensional pattern in its surface to shus transfer said pattern to a surface of said thermoplastic resin, simultaneously contacting the other side of said thermoplastic resin with a cooling roll having an uneven pattern or a mirror surface to thus transfer said pattern or mirror surface to a surface of said thermoplastic resin in contact with said cooling roll, and separating by peeling said release sheet from said thermoplastic resin after cooling. The continuous sheet is free of a streak and scratch and freely cuttable in any desired size and form.

Abstract: A process for the extrusion of plastic plates with very finely structured surface using an extrusion system which is equipped with an extruder and a three roll polishing stack containing a roller with the structuring surface. The system is designed for coextrusion and the plastic plates are produced via two extruders as a coextrudate CX from a highly viscous basic molding compound BF and a low viscosity molding compound NF which is extruded on BF. The surface of said plates is structured via the three roll polishing stack. Fresnel lenses produced by the process may be used in solar collectors.

Abstract: Improved two component polymerizable polyorganosiloxane compositions are described, particularly for use in making dental impressions, having improved tear strength and wettability. Improved tear strength results from inclusion of a quadri-functional polysiloxane having a vinyl content of 0.16 to 0.24 m-mole/g. Working time is maintained by including sufficient amounts of a retarder composition that delays onset of the vinyl polymerization. Wettability is improved by including a surfactant resulting in a surface contact angle with water at three minutes of less than 50.degree.. The surfactant chosen has an HLB of 8-11, such that the wetting contact angle is achieved within less than two minutes and remains wetting throughout the working time of the impression taking, substantially improving impression quality.

Abstract: A method of making a gradient index optical element includes a step in which a comonomer mixture is prepared. The comonomer mixture is then injected into a preformed forming body. The forming body containing therein the comonomer mixture is subsequently processed at a constant temperature to cause the forming body to swell. Finally, the comonomer mixture contained in the swelled forming body is polymerized.

Abstract: Improved two component polymerizable polyorganosiloxane compositions are described, particularly for use in making dental impressions, having improved tear strength and wettability. Improved tear strength results from inclusion of a quadri-functional polysiloxane having a vinyl content of 0.16 to 0.24 m-mole/g. Working time is maintained by including sufficient amounts of a retarder composition that delays onset of the vinyl polymerization. Wettability is improved by including a surfactant resulting in a surface contact angle with water at three minutes of less than 50.degree.. The surfactant chosen has an HLB of 8-11, such that the wetting contact angle is achieved within less than two minutes and remains wetting throughout the working time of the impression taking, substantially improving impression quality. A low viscosity impression material is provided and includes a base component and a catalyst component. Both components are siloxane-based materials.

Abstract: A mold 79 that includes an array of cube-corner elements 80 that are arranged in the array such that a retroreflective cube-corner sheeting 60 that is formed thereon is capable of glittering when light is incident on the sheeting. The array may be defined by three sets of intersecting grooves 25, 26, 27 where each groove set includes two or more generally parallel grooves. At least one groove in at least one of the sets has faces 22 of adjacent cube-corner elements 30a, 30b arranged such that a dihedral angle .alpha. located between adjacent faces varies along the groove(s) in the set.

Abstract: A method for making caps of eight different sizes for each of a persons teeth allows premaking caps that will fit almost any tooth of any patient; caps are preferably prepared from a commercially available quartz or silicon dioxide filled acrylic material called Artglass r; the caps allow curing a material such as Charisma r with ultraviolet light thereby allowing a practitioner to place a cap containing Charisma r over a tooth prepared for capping; settle the cap in place; remove any excess and expose the capped tooth with a ultraviolet light for about three minutes to form a solidly capped tooth in one visit to the practitioners office.

Abstract: An improved method for simplifying a slip casting applied conventional all ceramic core molding process by molding an all ceramic core from a ceramic sheet. In the method, there is prepared a slurry which consists mainly of alumina, spinel, alumina/zirconia powder, by adding thereto a dispersant, a binding agent, a plasticizer, a solvent and the like. The slurry is formed into a sheet having a thickness of 0.1 mm to 1.0 mm for thereby fabricating a tooth molding mass by using a heat hydrostatic pressing at a pressure of 15 Kgf/cm.sup.2 to 150 Kgf/cm.sup.2 at a temperature of 50.degree. C. to 110.degree. C., with slurry composition for fabricating an all ceramic jacket crown applicable to an artificial crown.

Abstract: A dental care material comprising a titanium sintered body has no harmful effects on the human body and easily produces products with complicated shapes having a high level of strength. A mixture of titanium powder and an organic binder is injection molded and subjected to binder removal and sintering processes to form a bracket for orthodontic or dental implant materials. Pure titanium powder, with an average granule diameter of no more than 40 .mu.m, a carbon content by weight of no more than 0.3%, and an oxygen content by weight of no more than 0.6%, preferably is used to produce a titanium sintered body of combined carbon and oxygen content by weight of no more than 1.0%. Colored layers can be formed on the surface of the titanium sintered body using various methods as needed.

Abstract: Roll-forming apparatus and method for more precisely shaping an extruded-plastic Fresnel lens. A drive/support roller is rotatably mounted to the support frame and the surface of which engages and rotates to support the smooth outer surface of an extruded arcuate, elongated linear Fresnel lens. A tooth-forming roller is rotatably mounted to the support frame and has an external profile with tooth-forming projections formed thereon for engagement with the grooves on the inner surface of the extruded sheet, said tooth-forming roller being positioned on the inner surface of the Fresnel lens opposite the drive/support roller and being loosely mounted on the support frame to track the grooves formed in the Fresnel lens to improve the profile of the lens section by sharpening the root radius and flattening the optical face of each lens section.

Abstract: A glass body for optical fiber containing GeO.sub.2 --SiO.sub.2 glass in a core portion thereof, in which the GeO.sub.2 --SiO.sub.2 glass has an absorbance at 5.16 eV of at least 1/mm but not higher than 2.5/mm or in which concentration of Ge.sup.2+ contained in the GeO.sub.2 --SiO.sub.2 glass substantially lies within the range of 1.1.times.10.sup.-9 to 2.8.times.10.sup.-9 mol/mm.sup.3 as calculated by the following general equation:A=.epsilon..sub.5.16ev .multidot.C.sub.(Ge2+) .multidot.1wherein A is absorbance which is expressed by A=-log T (T being transmittance) and normalized per 1 mm of optical path length, C.sub.(Ge2+) is Ge.sup.2+ concentration, .epsilon..sub.5.16ev is absorption coefficient (1/mol/cm), and 1 is optical path length.

Abstract: A roller-shaped stamper has a scale portion with a light transmitting forming portion for forming the light transmitting portion on the resin, and a light shield forming portion for forming the light shielding portion of the resin, wherein the forming portions are alternately arranged with a constant pitch in a direction of rotation of said roller-shaped stamper; a plurality of scale portions are arranged in a direction normal to the direction of rotation of the roller-shaped stamper; and a groove disposed between the plural scale portions and extending in the direction of rotation of the roller-shaped stamper for exhausting air otherwise trapped between the resin and the roller-shaped stamper.

Abstract: A cube corner article and method of manufacturing the article from a series of unitary substrates. A plurality of pins are assembled to form a mold having an array of cube corner elements on a surface. Then, a replica of the cube corner element array is produced in a substrate suitable for forming retroreflective surfaces. Portions of the replica substrate material are removed. The removal of these portions forms at least one cavity bounded by side walls in the replica at a depth at least that of the cube cube corner elements. The replica is replicated to produce an additional directly machinable substrate suitable for forming retroreflective surfaces having at least one raised section having sidewalls at a height at least that of the cube corner elements. At least one raised section is directly machined to form an array of cube corner elements.