Abstract: For the continuous automated production of powders that are well suited for hot pressing--i.e. those consisting essentially of spherical or cubic particles, of high-temperature resistant polymers without damage to the polymer structure in the course of the production process, a concentrated solution of the polymer in an aprotic polar solvent is continuously expressed into a twisting cone of hot aqueous precipitant. In doing so, short irregular wormy formations form, which are united to a fleece-like web, washed with aqueous solvents and finally with water, dried and comminuted. The plant provided for carrying out the process requires comparatively little space, since it does not include treatment tanks for extraction and drying.

Abstract: The formation of interfering polymer deposits in spary drying apparatus during the spray drying of aqueous dispersions or solutions of polymers in a stream of warm air is avoided if water is atomized together with the dispersion or solution.

Abstract: A method and system for forming a composite mixture of at least two materials, at least one of which is a metal or metal alloy. The materials in a molten state are supplied via inlet channels to a mixing region so as to indirectly impinge on each other and then to flow through an outlet channel to a cooling system, such as a casting or mold device or a device for providing rapid solidification thereof. The ratio of the cross-sectional area of the outlet channel to the sum of the cross-sectional areas of the inlet channels is arranged to be less than 32 and the ratio of the distance from the input side of the outlet channel to the input of the cooling system to the diameter of the outlet channel is arranged to be greater than 5.

Abstract: A resin composition for optics is disclosed, which mainly comprises a graft copolymer comprising a styrene resin and an aromatic polycarbonate each having a specific molecular weight at a specific ratio of molecular weight and weight, said composition having a micro disperse phase of not more than 0.5 .mu.m. The resin composition has a reduced optical strain and an excellent micro disperse phase and is, therefore, suitable for use as optics.

Abstract: An unsaturated compound having a vinyl or vinylidene group is rapidly in-mold polymerized by mixing the unsaturated compound containing a polymerization initiator and the unsaturated compound containing a polymerization accelerator, pouring the mixture into a mold cavity and polymerizing the monomer for not longer than 30 minutes.

Abstract: A soft contact lens of PVA having a tensile strength of not less than 10 kg/cm.sup.2, a water content ranging from 40 to 95% by weight, a visible light transparency of not less than 90%, and an oxygen permeability of not less than 30.times.10.sup.-11 cm.sup.3.(STP).cm/cm.sup.2.sec.mmHg. This soft contact lens can be prepared by forming a solution of PVA in a mixed solvent of water and an organic solvent, pouring the PVA solution in a mold having a shape of contact lens, and crystallizing at a temperature of not more than ordinary temperature. The soft contact lens has a high mechanical strength, high water content, high transparency and high oxygen permeability.

Abstract: A method for designing a molding apparatus, especially for molding lenses and the like, comprises defining a nominal mold reference curve disposed bewteen a pair of mold members having smooth, curved surfaces in confronting relationship to define a mold cavity therebetween. A plurality of concave and convex molding members are provided, all having differing molding surface curvatures but identical spacing from the respective curved surface to the nominal reference curve, measured from the point of closest approach of the curved surface to the reference curve. Any paired concave and convex molding surfaces have the same spacing from the reference curve and thus from each other, so that, for example, a universal gasket can be employed to hold any two paired convex and concave molding members in precise spacing, without regard to the curvature of the molding surfaces.

Abstract: An optical resin material comprising a polymer containing as an essential component at least one norbornyl acrylate or methacrylate or a derivative thereof is excellent in properties, particularly in moisture resistance and can be used for molding optical elements such as lenses, optical discs, etc.

Abstract: A mold and method is disclosed for the production of a lens that can be placed in or on the eye. The mold employs an inflexible ridge, preferably having a triangular cross section, on one of the mold parts. The ridge contacts the other mold part along an annular line.

Abstract: The arrangement comprises a carrier (1) having fibre-guiding grooves (2), which carrier is made of glass-like carbon. In the manufacture of the carrier the fibre-guiding grooves are formed in a cured phenol-resin body preferably by means of an extrusion die whose shape corresponds to that of the fibre-guiding grooves to be formed. The phenol-resin body thus formed is converted into the glass-like carbon carrier by carbonization.

Abstract: Rare earth oxysulfide ceramic material prepared by covering the material with a foil of a metal selected from the group consisting of molybdenum, tungsten, platinum, and rhenium, sealing it into an airtight vessel of tantalum or niobium, and then subjecting it to a hot isostatic press process.

Abstract: A soft and elastic intracameral lens, the back surface of which is formed by a continuous rotation-symmetric convex surface and the front surface comprises a central convex surface of sphere or quadric rotation-symmetric body linked on the diameter of 4 to 8 mm, preferably through a rounded transition, to a concave ring surface of a sphere or a toroid, whereas the distance between the concave ring surface and the back surface is 0.05 to 1.5 mm.The intracameral lens according to the invention is manufactured by charging a mold, which has the negative shape of the required front surface of the lens and is provided at the periphery with a sharp edge protruding by 0.05 to 1.5 mm above the end of the peripheral ring surface, with a monomer mixture as high as above the sharp edge to form a continuous convex meniscus and the mold with the monomer mixture is then exposed to polymerization conditions.

Abstract: An optical waveguide and method of fabricating waveguide structures is disclosed. More specifically, a method of producing an organic waveguide which comprises treating a transparent plastic substrate with a solution in a inert solvent of an organic dopant which is absorbed into the surface of the substrate, under conditions such that a surface layer is formed having a refractive index which is greater than that of the substrate. Said dopant has a higher affinity for the plastic's substrate than for the solvent.

Abstract: Substitutes for optical glasses are obtained by submitting to polymerization, in the presence of a free-radical initiator and in bulk, a polymerizable liquid composition containing:a monomer of diethyleneglycol bis(allylcarbonate);oligomers of diethyleneglycol bis(alllycarbonate);a monomer of tris(hydroxyethyl)isocyanurate tris(allylcarbonate); andat least one free-radical initiator.

Abstract: A method and apparatus for the polymerization cast molding of lenses from hydrophilic gels. A hydrophobic liquid which is essentially immiscible with a hydrophilic polymerization mixture is introduced into a mold having a hydrophobic surface, followed by dosing of the hydrophilic monomer mixture which is allowed to polymerize to form a drop which is pressed, while polymerizing, into the mold with a punch having a hydrophobic molding surface. The polymerizing monomer mixture is maintained under the pressure of the punch until the end of the polymerization. Any overflow of the two liquids is allowed to escape between the mold and the punch. The apparatus comprises a concave mold with an inner hydrophobic, rotation-symmetrical surface, and a punch with a hydrophobic molding surface which when placed in relationship to the mold has an overflow space formed between the mold and the punch.

Abstract: A plastic optical transmission element having a body in which the refractive index varies continuously in a radial direction from the interior toward the surface of the body, may be free from the troubles derived from irregularity of the index distribution and flare by having a layer containing a light-absorbing substance under the surface thereof. Such a layer may be formed by contacting an untreated element with a solvent containing the light absorbing substance, when the solvent is selected so as to be capable of at least partially dissolving the plastic of the element.

Abstract: An optical article is disclosed containing, for the transmission of electromagnetic radiation, a medium exhibiting a second order polarization susceptibility greater than 10.sup.-9 electrostatic units comprised of polar aligned noncentrosymmetric molecular dipoles. The molecular dipoles have an electron donor moiety linked through a conjugated .pi. bonding system to an electron acceptor sulfonyl moiety.

Abstract: An optic for an intraocular lens with finished, molded radii on the anterior and posterior edges of the peripheral surface of the optic. The optic has a thin central optical zone and a surrounding annular ring having sufficient material to support haptics. The ring is thicker than the optical zone and, thus, recesses the posterior surface of the optical zone to provide a capsulotomy space. The present novel optic is produced by novel molding pins which are shaped to provide the finished molded radii on the edges of the optic so that the optic requires little or no post-molding finishing or polishing other than the degating and deflashing.

Abstract: A process and apparatus for preparing a homogeneous dissipation of a viscous, liquid-dissipatable polymer. The process comprises continuously feeding molten polymer into a first inlet of a mixing chamber, feeding a stream of a relatively low viscosity dissipating liquid into a second inlet of said mixing chamber at an angle, at a velocity and at a flow rate relative to the structure of said chamber such that shearing action is created at the advancing end of the polymer to continuously erode the end of the polymer, and further mixing the polymer and dissipating liquid downstream from an outlet of the chamber to form a homogeneous dissipation of polymer in dissipating liquid.

Abstract: This invention relates to a method for preparing a lens or a lens array and apparatus for carrying out the method. The method comprises directing, in line of sight in a vacuum, the vapor of a substance, which is solid and transparent at ambient temperature, from a source of that vapor through a hole in a mask to form a deposit on a substrate. The mask is so positioned between the vapor source and the substrate that obscuration by the solid portions of the mask around the hole causes the deposit to assume a curved surface and function as a lens.

Abstract: A disk substrate for a high-density information recording medium made by injection molding from polycarbonate is disclosed having an average molecular weight from 14,000 to 22,000 and having a thickness from 1.0 to 2.0 mm and a circular recording area of between two concentric circles having a radii of 40 to 170 mm, respectively. The birefringence of the substrate within the recording area is less than 25 mm and is uniformly distributed.

Abstract: An intraocular lens capable of absorbing ultraviolet radiation and, additionally, a method for forming the lens is provided. The intraocular lens comprises a polymer matrix that is biocompatible with body tissue and fluids and comprises polymethylmethacrylate and a chromophoric compound. The intraocular lens preferably has about the same capability for absorbing ultraviolet radiation as does the natural crystalline lens of the eye. In one embodiment, the intraocular lens is formed by co-polymerizing a polymerizable derivate of 2,4-dihydroxybenzophenone and methyl methacrylate monomer to form an ultraviolet light absorbing co-polymer additive. The co-polymer additive is mixed with methyl methacrylate monomer for forming a prepolymer solution that is then cured. The intraocular lens is formed from the solid cured co-polymer.

Abstract: There is provided a method of manufacturing a ceramic, wherein a ceramic material is covered with a foil of a metal selected from the group consisting of molybdenum, tungsten, platinum, and rhenium, sealed into an airtight vessel of tantalum or niobium, and then subjected to a hot isostatic press process. The method of the present invention can suppress coloration produced in the hot isostatic press.

Abstract: The invention relates to a method of manufacturing a cable. In the cable, the conductors are surrounded entirely or partly by synthetic resin supporting elements. In order to avoid shrinkage of the supporting elements, and hence extra loads on cable at high temperatures, the supporting elements are preshrunk before assembly of the cable. The elements are preshrunk by heating a temperature just below the softening temperature of the synthetic resin in question, maintaining them at this temperature, and then cooling them. During the heating process, the strength elements are mounted in such a way that their contraction will not put them into tension.

Abstract: The invention relates to disc-shaped information carriers which can be read optically in reflection and which contain an annular information zone which is bounded by a concentric inner zone and a concentric outer zone. The information carrier consists of a transparent substrate and has a readout side and an opposite side (back) which at least in the information zone has a reflective coating. The light entering the outer zone from the readout side is reflected at least partially diffusely or absorbed by the information carrier. In this way, manufacturing defects such as, for example, inclusions, inhomogeneities etc. are at least partially masked or concealed.

Abstract: A method for utilizing a powder metallurgy ("P/M") slurry by employing water atomized metallic powders and subsequently reducing the oxide levels therein to acceptable levels. The slurry comprises a carbon containing binder. The slurry is consolidated and sintered under controlled conditions to reduce the oxide levels.

Abstract: Optical blanks, for example spectacle lenses, are produced by hot-blank pressing or injection molding of polyorganoheterosiloxanes which are obtainable by hydrolytic polycondensation of at least one titanium-, zirconium-or tin-compound, at least one organofunctional silane and, where applicable, at least one inorganic oxide component. For control of the optical characteristics and working properties, polyorganoheterosiloxanes which have a polymerizable organic radical may be modified by additional polymerization with other copolymerizable condensates or monomers.

Abstract: A technique for forming a composite mixture of materials, at least one of which is a metal, in which each of the materials is supplied in a molten or slurry state to separate channels. The materials are then supplied to one or more mixing regions substantially simultaneously where they are caused to impinge upon each other to form a composite mixture thereof. The composite mixture is supplied to one or more cooling regions for casting, the supplying of the materials to the separate channels, the forming of the composite mixture and the casting being performed in a substantially continuous operation.

Abstract: This light waveguide consists of an optically transparent body cut at one end to a sharp tip and polished optically flat at the other end. A metallization layer on its surface is thick enough to be opaque. By pressing the waveguide against a rigid plate the metallization is plastically deformed so as to expose a tiny aperture at the tip of the body through which light can pass. By carefully controlling the deformation of the metallization the diameter of the aperture can be kept between 10 and 500 nm. The waveguide can be incorporated in a semiconductor laser of a read/write head used in an optical storage device.

Abstract: Spherical hydrophilic contact lenses having a characteristic tricurve configuration designed to correct myopia (nearsightedness) are described. The center zone (A1) of the lens is substantially thinner than the periphery (A3) allowing enhanced oxygen transmission and comfortable, increased wearing times while the thicker mid-periphery (A2) imparts necessary integrity and handling characteristics for convenience in manual manipulation. Lenses are molded or cast directly in the desired tricurve configuration using specially designed replica molds made from metal master molds.

Abstract: A process for preparing shaped articles and shaped hydrogel articles including ophthalmic devices comprises the steps of preparing a polymer or copolymer comprising units derived from an ethylenically-unsaturated monomer bearing at least one trihaloacetoxy-substituent group, thermoforming said polymer by heating in a mold or in sheet-form at a temperature in the range of 100.degree. to 400.degree. C. for about 5 seconds to 15 minutes, and then cooling said polymer, to provide a shaped article, optionally, solvolyzing the resulting shaped article to provide a hydroxy-substituted polymeric shaped article, and optionally hydrating said hydroxy-substituted polymeric shaped article to provide a shaped hydrogel article.

Abstract: An article comprising a shaped, plastic layer or body comprising crosslinked polymer with hard and soft segments or moieties and having a microstructure-bearing surface is prepared by a process comprising filling a mold master, bearing or encoded with the microstructure to be replicated, with a fluid, castable, one-part, preferably solvent-free, radiation addition-polymerizable, crosslinkable, synthetic, organic oligomeric composition (or precursors thereof) having "hard" segments and "soft" polysiloxane segments, exposing the resulting case composition to radiation, preferably actinic radiation such as ultraviolet radiation, and thereby forming said article, e.g., a retroreflective cube-corner sheeting, Fresnel lens or video disc.

Abstract: A process for manufacturing an atomized amalgamable alloy having mold adaptation characteristics superior to other atomized alloys and comparable or better than those for ad-mixed type alloys (alloys which are mixtures of spherical and irregularly shaped particles), and physical properties comparable to ad-mixed alloys. The process includes the steps of: producing a melt of an amalgamable alloy; atomizing the alloy so as to form particles which are primarily irregular in shape; collecting the particles; drying the particles; mechanically working the particles so as to fracture and change their shape; classifying the particles to finer than 53 microns; heat treating the particles; and reducing oxides from the surface of the particles.

Abstract: A method of making a spin cast contact device having a circular aperture in the center. The central aperture has a thin tapered inner edge. A spin cast concave mold having a raised central area provides the aperture with thin tapered edges. The device is a non-optical plano in the center and provides color enhancement to the eye.

Abstract: A starting solution comprising one or more noncrystalline natural proteinaceous polymers of animal or vegetable origin is molded and gelled in a lens shaped mold and then removed from the mold. Thereafter the gel is crosslinked by immersion in a liquid containing a crosslinking agent.

Abstract: A method of coloring predetermined areas of cast contact lenses by placing a coating of soluble dye on the mold surface in the area to be colored. The liquid lens monomer is added to the mold and dissolves the dye from the mold surface before being polymerized to form a solid contact lens. After being polymerized the lens containing the dye in its polymer structure is removed from the mold.

Abstract: A spin cast cosmetic device to be worn on the cornea that changes the apparent color of the eye. The device has color bands of pigments and dyes which are separated by the spin casting operation. Pigment particles migrate and are separated, the dyes do not migrate. Unexpectedly the pigments separate into two concentric bands, one at the center and one at the periphery. The area between the pigment bands is colored by the soluble dye.

Abstract: The lens is molded in a rotating concave lens mold. Liquid lens monomer is placed in the concave mold and a controlled stream of gas from a narrow opening extending across the lens and positioned over the lens center shapes the concave surface to a toric. The lens mold and the gas nozzle rotate in synchronization until the lens monomer is polymerized.

Abstract: An intraocular lens capable of absorbing ultraviolet radiation and, additionally, a method for forming the lens is provided. The intraocular lens comprises a polymer matrix that is biocompatible with body tissue and fluids and comprises polymethylmethacrylate and a chromophoric compound. The intraocular lens preferably has about the same capability for absorbing ultraviolet radiation as does the natural crystalline lens of the eye. In one embodiment, the intraocular lens is formed by co-polymerizing a polymerizable derivate of 2,4-dihydroxybenzophenone and methyl methacrylate monomer to form an ultraviolet light absorbing co-polymer additive. The co-polymer additive is mixed with methyl methacrylate monomer for forming a prepolymer solution that is then cured. The intraocular lens is formed from the solid cured co-polymer.

Abstract: An oxygen-permeable contact lens consisting essentially of a polymer having an organic polysiloxane skeleton and a three-dimensional crosslinked structure, and a process for the preparation thereof.

Abstract: Soluble gas is introduced in a melt material which is then atomized and rapidly cooled. The cooling drives the gas from solution, further disintegrating the atomized material to an ultra-fine powder. In one embodiment the atomization and rapid cooling are effected using a gas atomization die. Introduction of the soluble gas may be effected by addition of reactive constituents to the melt, for reactively forming such gas. Finer powders with desirable metallurgical properties are formed using a metallic melt.

Abstract: The instant invention is concerned with the production of essentially transparent glass/plastic composite articles. The articles consist of glass particles having water-free surfaces and dimensions of about 0.5-100 microns dispersed within a plastic matrix, the glass particles constituting up to 50% by weight of the articles and having a refractive index appropriate to or compatible with the plastic matrix.

Abstract: In the particular embodiment described in the specification, a contact lens hydrogel is prepared by copolymerizing 75 parts of N-vinyl pyrrolidone and 23 parts of phenyl ethyl methacrylate together with allyl methacrylate as a crosslinker, t-butyl peroctoate as a thermal initiator and 2,2-dimethoxy-2-phenylacetophenone or benzoin methyl ether as a photoinitiator. The mixture is maintained at a temperature of 5.degree. C. and protected from light prior to photopolymerization which is carried out under ultraviolet radiation. The copolymer is then post-cured thermally. Cloudy or hazy hydrogels are avoided by preventing prepolymerization of the mixture.

Abstract: Optically clear soft contact lenses of aqueous swollen solid polyvinyl alcohol having a weight average molecular weight of at least 6,000, having been annealed under crystallinity promoting conditions to effectively increase the elastic modulus of the swollen lenses, and optionally subsequently crosslinked, and methods of preparation and the use thereof are disclosed. The lenses are characterized by their relatively high oxygen transmissibility, sufficient to meet the needs of the human cornea, high optical clarity, improved hot water resistance and superior mechanical properties.

Abstract: The invention pertains to a method for casting polymeric gels from volatile mixtures of monomers in open molds and to apparatus for performing this method.The principle of the invention resides in the fact that the same concentrations of volatile components present in the polymerization mixture are also present in the gaseous state within a protective gas maintained above the free surface of the polymerization mixture, said gaseous volatile components being in the equilibrium state with those in the polymerization mixture at polymerization temperature.The apparatus for performing said method comprises a main pipe branch which introduces a pure protective gas into a polymerization apparatus and at least one auxiliary pipe branch for saturating the protective gas with a volatile component.

Abstract: Polyolefin fibers, which are suited for at least partially substituting the cellulose fibers in the manufacture of paper, are produced by a process which consists in preparing in a pressure vessel a solution of a polyolefin at a temperature higher than the boiling temperature of the solvent under normal conditions, and under autogenous pressure or a pressure greater than the autogenous pressure, in ejecting said solution under the above stated conditions into a zone of lower pressure, in allowing the ejected solution to expand at least partially in said zone, and in then hitting the at least partially expanded solution with a jet of a high-speed fluid, which is at a temperature lower than that of the solution, and has an angled direction with respect to the direction of ejection of the solution.

Abstract: A process and apparatus for preparing a porous, particulate sulfur by combining a coherent molten sulfur stream with a coherent water stream to provide an aqueous slurry of a porous, particulate sulfur having a uniform particle size distribution. In the process of this invention, a molten sulfur stream is passed through a substantially downwardly oriented, rectangular slot to provide a sheet of molten sulfur, and said sheet of molten sulfur is sheared by directing at least one sheet of water thereat, at a velocity and flow rate sufficient to disrupt said sheet of molten sulfur and provide solid sulfur particles having a substantially uniform size. The solid sulfur particles are recovered, as an aqueous slurry thereof, and separated from said slurry by substantially removing the water therefrom.

Abstract: Granular solid particles, in particular hard, comminuted material of any given shape, are kept continuously in relative movement in a funnel-shaped container by means of a stream of liquid whereby they are rounded off. The rounded-off particles are suitable as filler material for wear-resistant coatings.

Abstract: An optical element, consisting essentially of an amorphous compound and having a varying refractive index, is prepared by introducing a melt of the material into a mold and cooling it in such a manner that the material gradually solidifies, while simultaneously applying a programmed pressure to the cooling melt. When the material is fully solidified, it possesses a refractive index gradient. An element manufactured by this method has a capacity for guiding and focusing light.

Abstract: A method is disclosed for manufacturing transparent plastic articles, primarily plano or opthalmic photoreactive lenses, which comprises incorporating fulgides or fulgimides containing an adamantylidene group in plastics casting or moulding compositions or preformed plastics articles and converting the fulgide or fulgimide in situ into a form in which it confers on the article the property of darkening in the presence of sunlight and fading in its absence.