Abstract: A mold of a glassware molding machine has two half-molds movable between a closed molding position and an open extraction position by a mold opening/closing assembly, wherein two actuating arms, each fitted to a respective half-mold, are rotated about respective fixed hinge axes by an actuator assembly having a central linear actuator, and two lateral linear actuators located substantially on opposite sides of the central actuator; the actuators having respective movable members translating respectively along a central axis and two lateral axes parallel to one another and to the fixed hinge axes; and the central axis being located at a distance from a plane of the lateral axes.

Abstract: A blow head mechanism for an I.S. machine wherein the blow head has a final blow tube. The final blow tube is supported for vertical displacement between an up position where the open end of the final blow tube is proximate the top of a blown parison and a down position where the open end of the final blow tube is proximate the bottom of a blown parison. The final blow tube is oscillated a plurality of times during the time when the blow head is “on”.

Abstract: A mold having a pair of mold halves defining a mold cavity for forming a glass container. There is an inner shell of the mold and an outer shell and a gap therebetween through which cooling gas flows. Heat transfer elements on the inner shell extend laterally outwardly from the inner shell into the gap for contact by cooling gas flowing through the gap thereby to cool the inner shell. The inner shell is formed from a hard material having a working temperature substantially greater than the melting temperature of glass, a heat conductivity of less than about 15 W/m-deg K, and a capability of generating at temperatures in excess of about 500.degree. C. a protective oxide film strongly adhered to the inner shell surface.

Abstract: A process for producing inorganic microspheres (solid spheres or hollow spheres), which comprises pulverizing a material by wet pulverization to an average particle size of at most 5 .mu.m to obtain a slurry of a pulverized powder material, spraying the slurry to form liquid droplets, and heating the liquid droplets to fuse or sinter the powder material to obtain inorganic microspheres.

Abstract: Provided is a method for the efficient preparation of fine hollow spherical glassy bodies having a high strength and excellent whiteness from a volcanic vitreous deposit as the starting material. The fine hollow spherical glassy bodies as desired can be prepared by dispersing 100 parts by weight of a powder of a volcanic vitreous deposit in an aqueous solution containing 1 to 10 parts by weight of aluminum sulfate, adding an aqueous alkaline solution to this liquid suspension to cause deposition of an alumina hydrate onto the surface of the particles of said powder and washing and drying of the solid material followed by a heat treatment for 1 second to 1 minute at a temperature of 900.degree. to 1100.degree. C.

Abstract: Evacuated microspheres, insulating materials constructed from such microspheres, and methods of manufacturing same provide insulation and reduce heat transfer through radiation, conduction and convection. Additionally, an infrared reflective coating is provided on a microsphere surface to reduce radiant heat transfer. A protective exterior coating is also provided to protect an exteriorly applied infrared reflective coating on such a microsphere. Furthermore, the spheroidal geometry of such microspheres restricts heat transfer to point-to-point conduction therebetween. Finally, evacuated microspheres further reduce through-heat transfer within a shell. One embodiment utilizes such evacuated microspheres in constructing an elastomeric roof coating which appreciably reduces cooling and air conditioning power costs for a building. An alternative embodiment utilizes such an elastomeric coating in constructing an exterior paint for a building.

Abstract: To produce a free-flowing granulate which has a high bulk density and a defined particle size distribution, which generates little dust, is easy to handle, and is suitable as a starting material for quartz glass products, the mixing operation includes a first mixing phase, in which the materials to be mixed are subjected to a slow mixing action to form a coarse-grained mass, and a second mixing phase, in which the coarse-grained mass is converted to a fine-grained mass by a more intensive mixing action which grinds and compacts the grains. The content of silica powder in the materials to be mixed is adjusted at least during the second mixing phase to a value of at least 75 wt. %.

Abstract: Proposed is an efficient method for the preparation of vitreous hollow microspheres from particles of a vitreous volcanic deposit by a heat treatment to effect expansion of the particles by foaming. The inventive method comprises a step, prior to the heat treatment for expansion of the particles, in which the starting particles are dispersed in an aqueous medium containing aluminum sulfate and urea each in a specified concentration followed by a heating treatment of the dispersion so as to deposit a coating layer of aluminum hydroxide on the particle surface so that the efficiency of foaming can be greatly improved without the disadvantage of particle agglomeration.

Abstract: The present invention provides hollow borosilicate microspheres having a mean particle size between 15 and 20 microns, and a true density below 0.25 g/cc. The invention also provides a method for making such microspheres comprising spray drying a solution of sodium silicate and sodium borate in a spray tower to form a precursor, milling the precursor, and heating the crushed precursor to a temperature in excess of 600.degree. F. to form hollow borosilicate microspheres.

Abstract: Hollow microspheres produced by the present method each have a hollow interior evacuated of gases to a predetermined pressure. A reflective material layer coats the exterior of each microsphere and, optionally, an outer layer of a protective material is applied over the reflective material layer. Permeant gases are dissolved into glass or plastic frit particles prior to heating of the frit particles to form hollow microspheres having the permeant gases contained therein. The permeant gases are subsequently out-permeated in a non-permeant gas atmosphere to substantially evacuate the interior of each microsphere. The exterior layers of reflective material and protective material are then coated about each evacuated microsphere.

Abstract: Hollow microspheres produced by the present method each have a hollow interior evacuated of gases to a predetermined pressure. A reflective material layer coats the exterior of each microsphere and, optionally, an outer layer of a protective material is applied over the reflective material layer. Permeant gases are dissolved into glass or plastic frit particles prior to heating of the frit particles to form hollow microspheres having the permeant gases contained therein. The permeant gases are subsequently out-permeated in a non-permeant gas atmosphere to substantially evacuate the interior of each microsphere. The exterior layers of reflective material and protective material are then coated about each evacuated microsphere.

Abstract: Hollow porous microspheres of uniform diameter and of uniform wall thickness are disclosed. The walls of the hollow microspheres comprise sintered together particles which define interconnecting voids within the walls and a single central cavity in the interior of the microspheres and inner and outer microsphere wall surfaces. The interconnecting voids are continuous and extend from the outer wall surface to the inner wall surface. The walls have uniform void content and the interconnecting voids are uniformly distributed in the walls of the hollow microspheres and the walls of the hollow microspheres are free of latent solid or liquid blowing gas materials and are substantially free of relatively thinned wall portions and bubbles. The hollow porous microspheres include microspheres in which the interconnecting voids have been closed and sealed.

Abstract: Processes and apparatus for the production of hollow microspheres by thermal expansion of glass particles including the thermal treatment of extremely small glass particles whose dimensions are less than 50 micrometers and, preferably, less than 35 micrometers or even 20 micrometers, which include a fluidizing agent. This technique makes possible the production of extremely small glass microspheres under satisfactory yield conditions. Also, the hollow microsphere products produced by these processes and apparatus.

Abstract: A method is described for making hollow aerogel microspheres of 800-1200 .mu. diameter and 100-300 .mu. wall thickness by forming hollow alcogel microspheres during the sol/gel process in a catalytic atmosphere and capturing them on a foam surface containing catalyst. Supercritical drying of the formed hollow alcogel microspheres yields hollow aerogel microspheres which are suitable for ICF targets.

Abstract: Method for making hollow microspheres of substantially uniform diameter and of substantially uniform wall thickness is disclosed. The walls of the hollow microspheres comprise sintered together particles which define interconnecting voids within the walls and a single central cavity in the interior of the microspheres and inner and outer microsphere wall surfaces. The interconnecting voids are continuous and extend from the outer wall surface to the inner wall surface. The walls have substantially uniform void content and the interconnecting voids are substantially uniformly distributed in the walls of the hollow microspheres and the walls of the hollow microspheres are free of latent solid or liquid blowing gas materials and are substantially free of relatively thinned wall portions and bubbles. The method includes heating the microspheres for a sufficient period of time to close and seal the interconnecting void.

Abstract: Hollow porous microspheres of substantially uniform diameter and of substantially uniform wall thickness are disclosed. The walls of the hollow microspheres comprise sintered together particles which define interconnecting voids within the walls and a single central cavity in the interior of the microspheres and inner and outer microsphere wall surfaces. The interconnecting voids are continuous and extend from the outer wall surface to the inner wall surface. The walls have substantially uniform void content and the interconnecting voids are substantially uniformly distributed in the walls of the hollow microspheres and the walls of the hollow microspheres are free of latent solid or liquid blowing gas materials and are substantially free of relatively thinned wall portions and bubbles.

Abstract: Low sodium hollow glass microspheres containing less than about 3 wt. % Na.sub.2 O are produced from aqueous precursors. The method comprisesa) forming an aqueous glass precursor solution or slurry by combining sources of cations contained in the glass, the solution or slurry comprising all of the glass cations in proportions substantially identical to those in the glass,b) forming the solution or slurry into droplets, andc) heating the droplets to form the microspheres.The precursor may also contain surfactants, blowing agents or other known expedients. Nonionic fluorocarbon surfactants are preferred.The droplets may be formed by spraying or any other known technique. The droplets may be spray dried prior to heating step c).

Abstract: A composite insulator is formed having evacuated hollow plastic enclosures arranged in a closely packed configuration with a foamed plastic resin filling the interstice between the plastic enclosures. According to a preferred aspect of the invention, hollow evacuated spheres are embedded into a matrix of polyurethane foam. The composite insulator can be formed directly within an insulating cavity of an appliance or can be formed into customized panels which can be inserted into an appliance. Also, disclosed is a method of manufacturing the composite insulator by forming a seamless continuous plastic wall on a molding chamber that has been at least partially evacuated, incorporating the resulting hollow plastic enclosure into a plastic resin which is capable of being foamed in place, introducing the composite into an enclosed cavity that is to be filled with insulation, and causing the plastic resin to foam in place.

Abstract: Small hollow glass spheres are prepared by adding a surfactant to a liquid glass precursor mixture. The surfactant-containing solution or dispersion can be formed into droplets which are directed into a heated zone and the product collected in a cooler zone. Alternately, the solution or dispersion may be spray-dried, and the spray-dried product is fed into the heated zone and collected in the cooler zone. Nonionic fluorocarbon surfactants are the preferred surfactants.

Abstract: A process for making a hollow spherical shell of silicate glass composition in which an aqueous suspension of silicate glass particles and an immiscible liquid blowing agent is placed within the hollow spherical cavity of a porous mold. The mold is spun to reduce effective gravity to zero and to center the blowing agent, while being heated so as to vaporize the immiscible liquid and urge the water carrier of the aqueous suspension to migrate into the body of the mold, leaving a green shell compact deposited around the mold cavity. The green shell compact is then removed from the cavity, and is sintered for a time and a temperature sufficient to form a silicate glass shell of substantially homogeneous composition and uniform geometry.

Abstract: A process for making non-porous, dense, silica partices having a diameter of about 3 to 1000 microns, a nitrogen B.E.T. surface area less than about 1 m.sup.2 /g, a total impurity content of less than about 50 ppm and a metal impurity content content of less than about 15 ppm from an aqueous dispersion of fumed silica. The particles are converted into porous particles and sintered in an atmosphere having a water partial pressure of from about 0.2 to about 0.8 atmosphere for temperatures below about 1200.degree. C.

Abstract: A method is described for forming hollow particles, or shells, of extremely small size. The shell material is heated to a molten temperature in the presence of a gas that is at least moderately soluble in the shell material, to form a solution of the molten shell material and the soluble gas. The solution is atomized to form a multiplicity of separate droplets that are cooled while in free fall. Cooling of a droplet from the outside traps the dissolved gas and forces it to form a gas bubble at the center of the droplet which now forms a gas-filled shell. The shell is reheated and then cooled in free fall, in an environment having a lower pressure than the gas pressure in the shell. This causes expansion of the shell, to form a shell having a small wall thickness compared to its diameter.

Abstract: Ultra-fine hollow glass spheres suitable as a filler in light-weight composite materials for building use and the like can be prepared from a fine powder of volcanic glass even when the starting powder has a particle size as fine as 20 .mu.m or smaller. The inventive method comprises an acid-leaching treatment of the starting powder using hydrochloric or sulfuric acid under hydrothermal conditions at 150.degree.-200.degree. C. to modify the chemical composition in the surface layer of the particles and a subsequent heat treatment of the acid-treated particles at a specified high temperature to effect expansion by the water vapor produced from the structural water in the softened particles. By virtue of the modified composition in the surface layer and in contrast to the prior art method without the acid treatment, a good balance can be obtained between the rate of water vapor release and softening of the particles even when the particle size is extremely small to facilitate expansion of the particles.

Abstract: A process of manufacturing vitreous beads in which particulate feedstock is delivered to a heated chamber and passed along it so that the feedstock is heated and converted to vitreous beads whereafter the beads are collected, characterised in that the chamber is shaped to provide a flow path for the particles which is of elongate cross-section and is arranged so that the particles pass downwardly through it under gravity, and in that the particles passing through the chamber are heated by radiant heating means which emanates from the chamber walls.

Abstract: Porous glass shapes with effective pores are produced by a method which also reduces the frequency of breakage of the glass shapes. The method includes: producing a plurality of the glass shapes, depositing a fluid chemical treatment with one or more carbonaceous materials on a substantial portion of the surfaces of the glass shapes, heat treating the glass shapes to phase separate components of the glass, leaching the phase separated glass shapes to remove leachable components to produce pores in the glass shapes, and removing any residual carbonaceous material. The various forms of glass shapes include particles, platelets, flakes, beads, fibers both solid and hollow, tubes and capillaries, which are essentially free of carbonaceous material.

Abstract: Hollow shells of high uniformity are formed by emitting liquid through an outer nozzle and gas through an inner nozzle, to form a hollow extrusion, by flowing the gas at a velocity between about 1.3 and 10 times the liquid velocity. The natural breakup rate of the extrusion can be increased to decrease shell size by applying periodic perturbations to one of the materials prior to exiting the nozzles, to a nozzle, or to the extrusion.

Abstract: A composite suitable for use as dental composite is provided by a glass material having a softening range of at least 10.degree. C. and having a particle size of less than 250 mesh to provide a precursor mix. The precursor mix is mixed with a fugitive pore forming material and a binder to form a pressable mix. The pressable mix is pressed at a pressure in excess of 5,000 pounds per square inch to form a sinterable mix. The sinterable mix is sintered for a period of time sufficient to remove said fugitive pore forming material and to form a sintered mass for crushing to form particles of less than 250 micrometers in size to be incorporated into a dental composite.

Abstract: Production of microspheres having a very high silica content produced from a starting glass whose silica content is less than 80% by weight, with the remainder being essentially made up of boron oxide and one or more alkaline oxide(s). This starting glass is reduced into fine particles by grinding, optionally mixed with a fluidizing agent, and then passed through the flame of a burner at a temperature at least equal to 1500.degree. C. to form molten hollow microspheres which are suddenly cooled to form solid hollow microspheres. The microspheres produced thereby are recovered and contacted with a dealkalization agent to increase the silica content thereof to at least 92%.

Abstract: A spherulizing furnace for manufacturing vitreous beads includes feed means for delivering particulate feedstock, a spherulizing zone in which the feedstock particles may be heated and converted to vitreous beads, and means for collecting the resulting beads, wherein the feed means includes a reservoir adapted to hold a fluidized bed of feedstock particles, the reservoir having at least one overflow feed outlet opening over which fluidized particles flow under gravity for delivery to the spherulizing zone. A process of manufacturing vitreous beads, and vitreous beads made thereby, includes delivering feedstock to a spherulizing zone of a spherulizing furnace, passing the feedstock through the spherulizing zone so that the feedstock is heated and converted to vitreous beads, and collecting the beads. The feedstock particles are delivered under gravity by fluidized overflow from a fluidized bed reservoir to the spherulizing zone.

Abstract: Fiber reinforced hollow microspheres made from dispersed particle film forming compositions including fibers, dispersed particles, a binder, a film stabilizing agent, a dispersing agent and a continuous liquid phase. Porous and non-porous fiber reinforced hollow microspheres can be made. The fiber reinforced hollow microspheres have walls with voids which are interconnected to each other and to the inner and outer wall surfaces, and the fiber reinforced hollow microspheres can be used as membrane substrates in selective separation processes and in biotech processes. The fiber reinforced hollow microspheres can be used as supports for catalysts and as enclosures for catalysts, adsorbents and absorbents. The fiber reinforced hollow microspheres can also be used as filler materials and as proppants for increasing gas recovery from gas wells.

Abstract: Processes and apparatus for the production of hollow microspheres by thermal expansion of glass particles including the thermal treatment of extremely small glass particles whose dimensions are less than 50 micrometers and, preferably, less than 35 micrometers or even 20 micrometers, which include a fluidizing agent. This technique makes possible the production of extremely small glass microspheres under satisfactory yield conditions. Also, the hollow microsphere products produced by these processes and apparatus.

Abstract: Hollow microspheres are made by a process which comprises forming a film of a dispersed particle film-forming composition (containing dispersed particles, a binder, a film stabilizing agent and a continuous liquid phase) across a coaxial blowing nozzle, applying a blowing gas at a positive pressure on the inner surface of the dispersed particle composition film to blow the film and form, in the region of the coaxial blowing nozzle orifice, hollow dispersed particle microspheres having stable film walls, removing the hollow microspheres, treating them to bring dispersed particles into point to point contact and harden them to obtain hollow green microspheres, and subsequently subjecting them to a sufficiently high temperature for a sufficient period of time to remove the continuous liquid phase and to sinter the dispersed particles at their points of contact to form within the walls of said hollow microspheres interconnecting voids that are continuous from the outer wall surface to the inner wall surface of th

Abstract: A method is provided for producing commercially large quantities of high melting temperature solid or hollow spherical particles of a predetermined chemical composition and having a uniform and controlled size distribution. An end (18, 50, 90) of a solid or hollow rod (20, 48, 88) of the material is rendered molten by a laser beam (14, 44, 82). Because of this, there is no possibility of the molten rod material becoming contaminated with extraneous material. In various aspects of the invention, an electric field is applied to the molten rod end (18, 90), and/or the molten rod end (50, 90) is vibrated. In a further aspect of the invention, a high-frequency component is added to the electric field applied to the molten end of the rod (90).

Abstract: A method for making uniform spherical shells. The present invention allows niform hollow spheres to be made by first making a void in a body of material. The material is heated so that the viscosity is sufficiently low so that the surface tension will transform the void into a bubble. The bubble is allowed to rise in the body until it is spherical. The excess material is removed from around the void to form a spherical shell with a uniform outside diameter.

Abstract: A method for producing glass bubbles, which comprises heating a glass powder containing a gas-blowing agent in an atmosphere containing steam having a partial steam pressure of at least 0.2 atmosphere to foam it.

Abstract: Hollow microspheres are made by a process which comprises forming a film of a dispersed particle film-forming composition (containing dispersed particles, a binder, a film stabilizing agent and a continuous liquid phase) across a coaxial blowing nozzle, applying a blowing gas at a positive pressure on the inner surface of the dispersed particle composition film to blow the film and form, in the region of the coaxial blowing nozzle orifice, hollow dispersed particle microspheres having stable film walls, removing the hollow microspheres, treating them to bring dispersed particles into point to point contact and harden them to obtain hollow green microspheres, and subsequently subjecting them to a sufficiently high temperature for a sufficient period of time to remove the continuous liquid phase and to sinter the dispersed particles at their points of contact to form within the walls of said hollow microspheres interconnecting voids that are continuous from the outer wall surface to the inner wall surface of th

Abstract: A system is described for forming accurately spherical and centered fluid-filled shells, especially of high melting temperature material. Material which is to form the shells is placed in a solid form in a container, and the material is rapidly heated to a molten temperature to avoid recrystallization and the possible generation of unwanted microbubbles in the melt. Immediately after the molten shells are formed, they drop through a drop tower whose upper end is heated along a distance of at least one foot to provide time for dissipation of surface waves on the shells while they cool to a highly viscous, or just above melting temperature so that the bubble within the shell will not rise and become off centered. The rest of the tower is cryogenically cooled to cool the shell to a solid state.

Abstract: The invention relates to a process and apparatus for producing hollow glass microspheres. According to embodiments of the invention, particles of a soda-lime-silica glass containing slight amounts of sulfur compounds are suspended in a gaseous current and expanded in a burner, at a treatment temperature at least 100.degree. C. above the working temperature at which the specific type of glass constituting the treated particles is made from its raw materials, such as sand, lime, sodium carbonate, sodium sulfate, and others, depending on the particular type of glass. The process makes it possible to increase the yield of the transformation of the particles.

Abstract: An apparatus is provided for forming gas-filled spheres of metal, glass or other material, which produces spheres (12) of uniform size and wall thickness in a relatively simple system. The system includes concentric nozzles, including an inner nozzle (18) through which gas flows and and an outer nozzle (20), which jointly define an annular passageway (50) through which a liquid flows. The flow rates are adjusted so that the gas flows at greater velocity than does the liquid, out of their respective nozzles, e.g. three times as great, in order to produce an extrusion (30) which undergoes axisymmetric oscillations resulting in the pinch off into hollow spheres with very uniform spacing. The system is useful not only where gas-filled spheres are required, but also is useful to accurately control the dispensing of solid, liquid, or gaseous materials.

Abstract: Suspensions of particulate oxides, e.g., fumed silica, are prepared in non-aqueous media and the suspensions are used to cast shapes for glass or ceramic products. The suspensions are formed and then caused to gel by means of an added gelling agent, and thereafter dried and, optionally, sintered to transparent glass or void-free ceramic products.

Abstract: This invention relates to a process for producing a hollow microsphere wherein the inner portion of the shell of which comprises the reaction product of a silicate and a first insolubilizing agent, the outer portion of the shell of which comprises the reaction product of a silicate and a second insolubilizing agent and wherein the equivalent ratio of silicate to, respectively, the first and second insolubilizing agent is less in respect of said inner portion than said outer portion.

Abstract: Large, uniform hollow spherical shells are produced by forming uniform size drops of heat decomposable or vaporizable material, evaporating the drops to form dried particles, coating the dried particles with a layer of shell forming material, and heating the composite particles to melt the outer layer and decompose or vaporize the inner particle to form an expanding inner gas bubble which expands the outer layer. By cycling the temperature and pressure on the hollow shells, spherical shells with uniform walls are produced.

Abstract: A method of producing gas filled hollow glass beads comprises the steps of:i. manufacturing hollow glass beads having an alkali content of at least 20% calculated as weight per cent of oxide in the bead,ii. exposing the beads to an acidic treatment medium, for example HCl, HNO.sub.3, H.sub.2 SO.sub.4, SO.sub.2, SO.sub.3, to reduce the alkali content of the beads to not more than 15%, andiii. causing gas to diffuse into the beads.

Abstract: Relatively long metal microfilaments are used to make superior high strength structural materials and/or are used as reinforcing materials in plastic and rubber compositions. A blowing gas is applied at a positive pressure to the inner surface of a metal film formed across a coaxial blowing nozzle to blow the film and form an elongated hollow tube having a thinned wall or weakened portion. An entraining fluid is directed at an angle over and around the blowing nozzle and as it passes over and around the blowing nozzle fluid dynamically induces a pulsating or fluctuating pressure field at the opposite side of the blowing nozzle in the wake thereof and produces a laminar flow of entraining fluid in the vicinity of the forming elongated tube.

Abstract: A method of forming rounded vitreous beads in which particles of bead forming material entrained in a gas stream having comburent and combustible components are projected from a burner head and the gas is burnt. A first component of the combustible gas mixture with entrained particles is propelled along a passageway leading to the burner head, a second gas component is forced transversely into that passageway through at least one orifice in its peripheral wall and the mixed gases in which the particles are entrained are subjected to forces further promoting intimate mixture thereof before reaching the burner head.

Abstract: There is disclosed a method of producing a cellular ceramic body of high mechanical strength and exhibiting a density less than 15 lbs/ft.sup.3. A crystal-containing gel, prepared from a selected, synthetic, lithium and/or sodium, water-swelling mica, is ion exchanged with a large cation to flocculate the gel and the floc is drained and provided with a gas producing agent. The floc is then molded to desired shape and subjected to gas-producing radiation to cellulate the molded body. The cellulating agent may be retained water, one or more chemical blowing agents, a combustible substance or a vaporizable substance. The floc, in slurry form, may have a thickener added to produce a paste prior to molding. It may also have a plasticizer and/or a binder added as modifiers.

Abstract: A method for making hollow glass microspheres with conducting surfaces by adding a conducting vapor to a region of the glass fabrication furnace. As droplets or particles of glass forming material pass through multiple zones of different temperature in a glass fabrication furnace, and are transformed into hollow glass microspheres, the microspheres pass through a region of conducting vapor, forming a conducting coating on the surface of the microspheres.

Abstract: A process is described for the formation of hollow glassy generally spherical particles ("microspheres") from natural mineral zeolites. A zeolite (or a mixture of zeolites) is rapidly heated to a temperature above its liquidus temperature to melt its surfaces, vaporize its combined water and cause it to expand to form the microspheres. The microspheres have diameters in the range of 1 to 500 millimeters and densities of about 0.1 to 2.0 g/cm.sup.3. They are useful as fillers and extenders in many materials such as plastics, and, because of their resistance to alkaline attack, are especially useful as fillers in cementitious materials.

Abstract: A sonic levitation apparatus (A) is disclosed which includes a sonic transducer (14) which generates acoustical energy responsive to the level of an electrical amplifier (16). A duct (B) communicates with an acoustical chamber (18) to deliver an oscillatory motion of air to a plenum section (C) which contains a collimated hole structure (D) having a plurality of parallel orifices (10). The collimated hole structure converts the motion of the air to a pulsed, unidirectional stream providing enough force to levitate a material specimen (S).

Abstract: A method is disclosed for producing low density, ceramic bodies in the nature of hollow or solid beads which may be used as such or bonded into a unitary mass. The bodies are composed of ion-exchanged, synthetic mica crystals wherein large cations, such as K.sup.+, have been exchanged for lithium and/or sodium ions from the mica. The method involves forming a gel by dissolution of a synthetic mica in a polar liquid, releasing droplets of the gel into a fluid to form shaped bodies, effecting the indicated ion exchange, and drying the beads thus formed.