Abstract: A porous ceramics body for in vivo or in vitro 1use in which a number of pores are closely distributed in three dimensional directions, adjoining pores thereof being partitioned by wall portions with respective communication ports to bring said adjoining pores into communication with each other such that a series of connected spherical pores are formed therewithin, said porous ceramics body being made of a sintered calcium phosphate body, characterized in that, within said sintered calcium phosphate body, pores each having a diameter of 5 microns (&mgr;m) or more account for 80% or more of all the pores in terms of volume whereas pores having a diameter of less than 5 microns (&mgr;m) account for less than 20% of all the pores in terms of volume as subjected to a mercury porosimeter measurement.

Abstract: The present invention provides methods for making a microporous ceramic material using a metal silicon powder and including a reaction sintering process of the silicon. A material for forming a microporous ceramic material used in these methods includes a metal silicon powder, a silicon nitride powder and/or a silicon carbide powder, and if desired, a yttrium oxide powder and/or an aluminum oxide powder. These methods can make a microporous ceramic material that can be used preferably as a gas or liquid filter, a catalyst carrier or a support of a gas separation membrane.

Abstract: A kit and a method for making a porous cement which self sets to hydroxyapatite and has an interconnected porosity is produced by mixing a calcium source and a phosphate source with a carbonate source and mixing this powdered component with a liquid component having an acid component. The liquid component comprises water or an aqueous solution containing an acid. The acid and the carbonate react to form carbon dioxide thereby producing an interconnected porosity in the normally solid self-hardening bone cement. The method requires only a relatively low weight percent of the acid and base to be mixed with the liquid and powder cement components.

Abstract: A lightweight heat-insulating building material which has excellent frost resistance and a low price is provided. The lightweight heat-insulating building material having frost resistance is produced by molding a mixture of raw materials containing glass powder, a foaming agent, a crystallization inhibitor, and a frost inhibitor so as to form a molded body, and firing the molded body so as to foam the molded body.

Abstract: A kit and a method for making a porous cement which self sets to hydroxyapatite and has an interconnected porosity is produced by mixing a calcium source and a phosphate source with a carbonate source and mixing this powdered component with a liquid component having an acid component. The liquid component comprises water or an aqueous solution containing an acid. The acid and the carbonate react to form carbon dioxide thereby producing an interconnected porosity in the normally solid self-hardening bone cement. The method requires only a relatively low weight percent of the acid and base to be mixed with the liquid and powder cement components.

Abstract: A lightweight heat-insulating building material which has excellent frost resistance and a low price is provided. The lightweight heat-insulating building material having frost resistance is produced by molding a mixture of raw materials containing glass powder, a foaming agent, a crystallization inhibitor, and a frost inhibitor so as to form a molded body, and firing the molded body so as to foam the molded body.

Abstract: The present invention relates to porous calcium zirconate/magnesia composites having a thermally and chemically stable porous structure, which consist of sintered compacts having a fine composite structure stable under high temperatures due to uniformly dispersed equimolar amounts of calcium zirconate [CazrO3] and magnesia [MgO] and controlled grain growth, and a method of producing the same, and the present porous composites are useful as, for instance, a functional material for filtering highly corrosion resistant materials, lightening members used at super-high temperatures, catalyst carriers, insulation or sound-absorbing materials, and the like.

Abstract: Slurries of metallic or ceramic powders are prepared in water which contains gas-eliminating substances such as carbonic acid, hydrogen peroxide, carbonates or hydrogen carbonates. This results in highly porous, solid cakes which may be processed by breaking and/or grinding to yield granules having a low fines content. Depending upon the intended application, the adhesively bound agglomerates may very readily be suspended, used as sintering precursors or as starting substances for solid-state reactions.

Abstract: The object of the present invention is to provide a refractory having sufficient corrosion resistance against alkali vapors and excellent thermal shock resistance which is light in weight and suitable for glass tank furnaces.

Abstract: Disclosed is a rigid fine-celled light-weight foam composition and a method of producing it which has improved retention of liquids by absorption/adsorption which improves the thermal insulation and fire retardant properties of the fine-celled foam particularly suited for use in double walled tanks and hollow canopies, building panels, profiles, and the like.

Abstract: The present invention provides a porous titania, which has an anatase-form crystalline structure, an anatase-form crystallite diameter of 3 nm to 10 nm, a degree of anatase crystallinity of 60% or more, a BET specific surface area of 10 m2/g or more, a total pore volume of 0.05 cm3/g or more, and a volume for pores having a pore radius of 1 nm or more of 0.02 cm3/g or more, and the porous titania and the catalyst comprising the porous titania of the present invention exhibit an excellent catalytic activity for removal of nitrogen oxides, oxidation of organic substances, decomposition of dioxine compounds, as well as decomposition and removal of organic solvents, agricultural chemical and surfactant.

Abstract: A method of forming foamed articles suitable for refractory, thermal insulation and construction application in a form such as bricks, blocks, slabs and discs includes the preparation of homogeneous mixture of at least one oxygen-containing, water-insoluble raw material having a particle size <200 microns and at least one gas forming reagent having a particle size <130 microns. The mixture is humidified and shaped and then heated to a formation temperature sufficient to melt the raw material to develop an oxygen-containing molten liquid phase. This phase reacts at the formation temperature with the gas-forming reagent to induce a foamed structure which is then cooled to a solid state. The raw materials preferably make up 99-99.95 wt % of the mixture, and the gas forming reagent makes up the balance.

Abstract: A calcium phosphate porous sintered body which comprises spherical pores communicating with one another substantially throughout the body with a porosity of 55% or more and 90% or less, and has an average diameter of the inter-pore communicating parts of 50 &mgr;m or more, a pore diameter of 150 &mgr;m or more, and a three-point bending strength of 5 MPa or more, and a method for producing the same.

Abstract: Substantially dry, self-hardening, thermally activated refractory compositions, suitable for use to produce linings for furnaces or metallurgical vessels such as ladles, tundishes or launders, comprise particulate refractory material, an inorganic binder having associated therewith chemically or physically bound water such as sodium metasilicate pentahydrate or tribasic sodium phosphate dodecahydrate, and an element or compound, such as aluminium, which will react exothermically with the inorganic binder. The compositions may also contain an inhibitor such as a mineral oil or a vegetable oil to inhibit premature exothermic reaction.

Abstract: Silicon carbide foam useful as a catalyst support has a BET specific surface area of at least 5 m2/g, and a compression strength exceeding 0.2 MPa. The foam is prepared by impreganting an organic foam with a suspension of silicon in a resin containing a cross-linking agent, incompletely cross-linking the resin, carbonizing the foam and resin, and carburizing the silicon.

Abstract: The invention disclosed is a self-supporting porous ceramic material, which is typically used in ceramic filters as a substrate prior to coating with a thin dense membrane layer of additional ceramic material. Conventional ceramic support structures are not necessarily designed as membrane support substrates. They are typically made with monosized particles and have a uniform cross section. The present support structure is made via a polydisperse slurry method where a functionally gradient structure is achieved by a colloidal destabilization technique. The key for achieving this structure is to colloidally unstable or metastable suspensions of a controlled and broad particle size distribution, so that segregation based on particle diameter will occur during consolidation. This produces a continuously finer mean particle diameter axial profile from one major surface to the other on the cross section of the consolidated structure.

Abstract: An alumina-based porous support with uniform physical properties is obtained in a rapid sintering process. An alumina raw material including a raw alumina powder and an inorganic binder is molded into an article, and the article is then sintered for 5 to 8 hours at 1520 to 1560.degree. C. using a roller hearth kiln.

Abstract: A process for preparing uniform, agglomerate free, submicron/nanosize ceramic powders from a polymeric foam comprising metal cations homogeneously incorporated within a foam cell structure of the polymeric foam. The polymeric foam is heated to remove any solvent, and calcined at a temperature of about 400.degree. C. to about 1400.degree. C. for about 1 minute to about 96 hours to produce the desired ceramic or metal powder.

Abstract: The present invention is embodied in a ceramic foam made by mixing a liquid pre-ceramic resin and a liquid phenolic resin, allowing the resultant mixture to chemically foam, curing the mixture for a time and at a temperature sufficiently to convert the mixture to a polymeric foam, and then heating the resultant polymeric foam for a time and at a temperature sufficient to break-down polymers of the polymeric foam and convert the polymeric foam to a ceramic foam. The ceramic foam of the present invention contains residual decomposed components of the liquid phenolic resin and/or liquid pre-ceramic resin.

Abstract: A ceramic particulate material which comprises particles having an irregular three dimensional surface profile having jagged projections and a median particle diameter of 200 micrometers or less, the particles being fractals produced by comminution of foamed ceramic material. The material may be such that in a sphere of rotation of the particle, from 30% to 80% of the volume of the sphere is void, the remainder being continuous solid material. The material may be produced by a process which includes providing a suspension of ceramic forming particles e.g., of an aluminosilicate such as clay, in a liquid medium; incorporating a gas in the liquid medium before or after formation of the suspension therein to produce a foamed suspension; extruding the foamed suspension; optionally drying the extrudate formed thereby; calcining the extrudate; and comminuting the calcined material, e.g. by crushing. The material may be used as a substitute for diatomite.

Abstract: A premix composition for producing an inorganic solid foamed mass by mixing component (A) an aqueous acidic phosphate solution of mainly polyvalent cations and phosphoric acid wherein between 0.8 and 1.75 protons of the phosphoric acid molecule of said phosphate are neutralized by the cations, which also contains one or more fillers dispersed therein, with (B) an oxide, hydroxide or polyvalent salt of a weak acid as hardener and a carbonate foaming agent. A process of producing an inorganic foamed mass using the premix composition and a solid foamed mass produced by the process are also disclosed. The process produces a relatively elastic cross-linked structure due to mainly the secondary phosphates being neutralized versus the tertiary phosphate groups.

Abstract: Opaque quartz glass is provided which contains gas bubbles uniformly dispersed therein and is excellent in high-temperature viscosity and heat-insulating property. The opaque quartz glass has a defined apparent density, contains bubbles having a defined average bubble diameter in a defined amount, has a defined total bubble sectional area, generally exhibits a defined linear transmittance at a thickness of 1 mm or larger to projected light of a defined wavelength and contains nitrogen in a defined concentration. The opaque quartz glass is produced by a process comprising packing into a mold a powdery source material of powdery silica having a defined average particle diameter and powdery silicon nitride dispersed therein in a defined amount, heating the powdery source material to one of two first defined temperature ranges (both under vacuum) and further heating the source material up to a second temperature higher than the melting point and not higher than 1900.degree. C.

Abstract: A foamed glass article for preparing surfaces, the use therefor, and a method of making same are provided. The foamed glass article is in the form of a block, disk or similar product, and is used for preparing surfaces such as by sanding, rubbing and scraping the same to clean, abrade, polish, smooth, or the like such a surface. The foamed glass article is formed from a starting mixture that comprised glass, 0.10-20% by weight of at least one non-carbon/sulfate based foaming agent, and optionally an additional abrasive material. A mixture of powdered glass and non-carbon/sulfate based foaming agent can be placed in a mold and heated so that the mixture sinters and subsequently foams. Thereafter, the foamed mixture is annealed.

Abstract: SiC foam-based catalyst carrier in the form of a moulded part having walls reinforced with a SiC skin having mechanical characteristics higher than those of the foam, this skin allowing the carrier to be handled and used without damage.

Abstract: A bearing material of silicon carbide particularly useful for application in the hot water field is provided having improved corrosion resistance under increased thermal stresses wherein the bearing material is characterized by a predominantly course-grained silicon carbide matrix of pressureless sintered silicon carbide having a biamodal grain sized distribution wherein the biomodal grain size distribution is formed by from 50 to 90% by volume of prismatic, tabular, silicon carbide crystallites having a length of from 100 to 1500 .mu.m and from 10 to 50% by volume of prismatic tabular silicon carbide crystallites having a length of from 5 to <100 .mu.m.

Abstract: A neutral pH foamed glass article is produced from a mixture of pulverized glass particles, foaming agent, binder, and water, wherein the glass article is heated to remove excess moisture and organic materals, then further heated to cause the foaming agent to emit a foaming gas, thereby causing foaming of the glass article. The foamed glass article is annealed in a controlled cooling fashion to avoid thermal stress, cracking and devitrification. The foamed glass articles may be used as artificial pumice stones in the stone-washed garment industry. Preferably, the mixture contains an amount of lignosulfonate to produce foamed glass having substantially neutral pH values in a range of from about 7.0 to 8.4.

Abstract: There is provided a light-weight ceramic acoustic absorber including an alumina based ceramic containing SiC whiskers, as a perforated body with a void ratio in the range of 80 to 92%, where there are voids with a mean diameter in the range of 50 to 450 .mu.m near the front surface of the body, and the void diameters are larger towards the rear surface of the body, and a mean diameter of the voids is in the range of 500 to 3,400 .mu.m near the rear surface of the body, and there is an increasing trend in void diameters from the front to the rear surfaces. The light-weight ceramic acoustic absorber provides various advantages such as light weight, high resistance to thermal stresses, high acoustic absorptivity, and high resistance to the gas jet from a jet engine.

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: A fibrous ceramic mat is molded from a slurry of ceramic fibers and/or ceramic microparticles and/or a metal. The mat is impregnated with a sol prior to drying. A catalyst for the sol is introduced into the mat to cause the sol to gel. The sol-gel binder forms bonds so that the mat is dimensionally stabilized. The mat is dried to produce the desired ceramic insulation that has preferably a consistent microstructure and a fully gelled sol-gel binder through its entire thickness. When a metal is used, it corrodes (i.e., oxidizes) or otherwise reacts to form a refractory binder that augments the sol and reduces the need to infuse sol incrementally to achieve strength. Using metal powder significantly reduces the cost of manufacture.

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: A foamed glass article for preparing surfaces, the use therefor, and a method of making same are provided. The foamed glass article is in the form of a block, disk or similar product, and is used for preparing surfaces such as by sanding, rubbing and scraping the same to clean, abrade, polish, smooth, or the like such a surface. The foamed glass article is formed from a starting mixture that comprised waste glass, 0.10-20% by weight of a non-sulfur based foaming agent, and optionally an additional abrasive material. A mixture of powdered waste glass and non-sulfur based foaming agent can be placed in a mold and heated so that the mixture sinters and subsequently foams. Thereafter, the foamed mixture is annealed.

Abstract: A mainly inorganic foam is produced by foaming a filler-containing, preferably primary aqueous polyvalent metal phosphate solution having a defined viscosity, then by neutralising and cross-linking most of the secondary phosphoric acid protons by polyvalent cations. As foaming agents preferably carbonates are added that rapidly decompose in the acid metal phosphate solution. Cross-linking is ensured by hardening accelerators adapted to the foaming agent, for example polyvalent metal oxides. Accurately describable foaming characteristics are thus obtained which may be defined, as for a polyurethane foam, as starting time, rising time and setting time.

Abstract: A method of obtaining glass materials from ash-slag. Waste wherein the waste is heated to a melting point temperature and melted in a reducing medium. The obtained melt is cooled by a thermal shock to form a foamed glass material. Prior to heating the charge, the carbon content therein is brought to 3.0-8.0 wt %, and the foamed glass material is foamed under a flow of a gaseous medium resulting form decomposition of carbides formed in the melt as a result of carbon content adjustment. Carbon addition also reduces iron oxide present in the waste, this reduction facilitating iron separation from the foamed material.

Abstract: Disclosed is a rigid fine-celled foam composition and a method of producing it. The foam composition is nontoxic, environmentally friendly, has improved absorption/adsorption and retention of liquids, is not as hard as prior art foams, does not include polymerization by-products detrimental to flower and plant life, and is a foamed mixture of a caustic silicate solution derived from the caustic digestion of rice hull ash having diffused activated carbon particles from thermal pyrolysis of rice hulls rather than from commercial sodium silicate solutions. Valuable by-products of commodity grade are obtained including activated carbon and sodium fluoride.

Abstract: A gas generating substance is added to an aqueous dispersion containing refractory particles and a polymerizable monomer and the pressure and/or temperature are adjusted so that the substance generates the gas before the polymerization gets underway; to control the formation of pores.

Abstract: A cellulated, inorganic body, and a method of producing the body, the body having a very low bulk density and being resistant to aqueous and chemical attack, the cells being gas- or vacuum-filled, predominantly closed, and dispersed in a crystalline matrix.

Abstract: The present invention is embodied in a method of producing a ceramic foam. The steps for producing the ceramic foam include first mixing a liquid pre-ceramic resin with a liquid phenolic resin, second allowing the resultant mixture to chemically foam, third curing the mixture for a time and at a temperature sufficiently to convert the mixture to a polymeric foam, and then heating the resultant polymeric foam for a time and at a temperature sufficiently to completely break-down polymers of the polymeric foam and convert the polymeric foam to a ceramic foam.

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: A method of obtaining glass materials from ash-slag. Waste wherein the waste is heated to a melting point temperature and melted in a reducing medium. The obtained melt is cooled by a thermal shock to form a foamed glass material. Prior to heating the charge, the carbon content therein is brought to 3.0-8.0 wt %, and the foamed glass material is foamed under a flow of a gaseous medium resulting form decomposition of carbides formed in the melt as a result of carbon content adjustment. Carbon addition also reduces iron oxide present in the waste, this reduction facilitating iron separation from the foamed material.

Abstract: A method of making a porous refractory article and a dispersion of particles in a liquid carrier, the method involving forming a dispersion of particles in a liquid carrier, introducing gas into the dispersion, removing the liquid carrier to provide a solid article having pores derived from the bubbles and wherein the dispersion has a critical viscosity below the level at which the introduction of gas cannot take place and above the level which entrapped gas bubbles will tend to escape and with the dispersion having the same critical viscosity.

Abstract: The invention is directed to a low density material suitable for use as an expendable liner in a molten metal handling vessel such as tundish. The low density materials include a first component having at least one decomposable compound capable of producing gas, a second component having a reactable compound for reacting with the decomposable compound in the presence of water to cause the decomposable compound to generate a gas, and a refractory aggregate. The invention also relates to a method for making the low density material and to the resultant material as well.

Abstract: The present invention is intended to provide a heat-insulating refractory material, which does not contain environmentally and hygienically undesirable ceramic heat-insulating fibers, but only contains organic fibers to the extent necessary to improve adhesive rate upon spraying, and which can nevertheless achieve a specified heat-insulating effect. The heat-insulating refractory material includes a mixture containing 2-50 wt % of a foaming raw material foamed by heat at a temperature from 400.degree. to 1500.degree. C. and 50-98 wt % of a refractory powder, and a liquid binder which is added to the mixture in an amount of 20-250 wt % on the basis of the weight of the mixture.

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: Disclosed is a process for preparing a solid, light weight mineral foam which is stable during its preparation and during its subsequent curing and drying and which, thanks to its composition and the way it is prepared, can be injected in situ, substantially like a urethane foam. This foam has a density ranging from 10 to 65 lb/pi.sup.3 and is made of 1 part by weight of a solution of phosphoric acid of given concentration in which is dissolved polyvinyl alcohol in such an amount as to make the solution viscous; from 0.03 to 6 parts by weight of wollastonite containing from 0.5 to 4% by weight of a carbonate salt; and from 0.2 to 10 parts by weight of water. The amount of water depends on the concentration of the solution of phosphoric acid and of the required density of the foam, it being understood that the more concentrated is the solution of phosphoric acid and/or the lower is the required density, the higher is the amount of water.

Abstract: Ceramic bodies having conically shaped pores are produced by electrophoretic deposition from aqueous ceramic particle suspensions. The dense ceramic bodies may be fabricated in the form of tubes having the pores radiating inward or outward. Alternatively, other shapes may be fabricated. The bodies are useful as filters, burner elements, catalysts supports, etc.

Abstract: A for preparing uniform, agglomerate free, submicron/nanosize ceramic powders from a polymeric foam comprising metal cations homogeneously incorporated within a foam cell structure of the polymeric foam. The polymeric foam is heated to remove any solvent, and calcined at a temperature of about 400.degree. C. to about 1400.degree. C. for about 1 minute to about 96 hours to produce the desired ceramic or metal powder.

Abstract: A soluble thermally cellulated, ceramic mold member, having gas evolved cells dispersed in a soluble crystalline matrix, the matrix consisting predominantly of at least one crystal phase selected from the group consisting of borates and phosphates of alkali metals, of divalent metals and of aluminum, and boron phosphate, and having at least one solubilizing agent selected from alkali metal compounds, divalent metal compounds and charred acrylic resin. A mixture capable of being thermally foamed to a cellulated body, the mixture consisting essentially of at least one phosphorous-containing compound, at least one boron-containing compound, at least one solubilizing agent selected from the group consisting of alkali metal compounds, divalent metal compounds and acrylic resins, at least one organic binder and a gas-evolving agent.

Abstract: The inorganic foam body consists of an at least partially open-cell foam formed by thermally foaming and hardening a mixture comprising an alkali water glass and a filler from the group of aluminum oxide, silicon dioxide, aluminous cement, crushed rocks, graphite or mixtures thereof. It is produced by heating a mixture comprising an alkali water glass and a filler from the group of aluminum oxide, silicon dioxide, aluminous cement, crushed rocks, graphite with a blowing agent, and preferably azodicarbonamide, at temperatures of at least 180.degree. C., and preferably of from 200.degree. C. to 300.degree. C. The foam body has a bulk density within the range of from 50 to 500 kg/m.sup.3, and preferably of from 50 to 400 kg/m.sup.3.

Abstract: This invention relates to a foamable silicate composition comprising (a) one or more alkali metal silicates, (b) a blowing agent, (c) a hardener which can be an acetate or a formate ester of a di-polyhydric alcohol or a polyoxyalkylene glycol and (d) a surfactant having a hydrophilic-lypophilic balance of at least 8. The formulations are readily produced by mixing the components, are pourable, pumpable and sprayable, and give rise to foams of excellent compressive strength and thermal insulation properties under ambient conditions.

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.