Abstract: This invention provides a calcium phosphate cement with relatively high surface pH which is very beneficial from the biocompatibility point of view. When calcium phosphate salts react with an acidic reagent to form cement, it normally involves the dissolution and recrystallization process. The acidity of the setting cements depends strongly on the nature of the calcium phosphate salt used, the acidity of the setting reagent, and the reaction rate. The present invention uses high alkaline calcium phosphate ceramics such as tetracalcium phosphate alone or together with calcium phosphate ceramics such as .alpha.-tricalcium phosphate as base cementing powder to increase the surface pH of the setting cement.

Abstract: A method for molding ceramic powders comprises forming a slurry mixture including ceramic powder, a dispersant, and a monomer solution. The monomer solution includes at least one monofunctional monomer and at least one difunctional monomer, a free-radical initiator, and a aqueous solvent. The slurry mixture is transferred to a mold, and the mold containing the slurry mixture is heated to polymerize and crosslink the monomer and form a firm polymer-solvent gel matrix. The solid product may be removed from the mold and heated to first remove the solvent and subsequently remove the polymer, whereafter the product may be sintered.

Abstract: The invention relates to a biomaterial for bony or dental fillings on the basis of apatite. It provides a biomaterial having antiseptic properties for limiting the proliferation of microorganisms at the site of implantation. The biomaterial according to the invention is based on calcium oxygenated phosphate having an apatitic structure which has oxygenated species with degrees of oxidation greater than or equal to -2. This biomaterial brings together with the antiseptic properties mentioned above an excellent biocompatibility, a very low solutility and good qualities of osteo-induction.

Abstract: A superhard form of boron suboxide (B.sub.x O) comprises at least about 95% by weight of polycrystalline B.sub.6 O and has a KHN.sub.100 value of at least about 3800 kg/mm.sup.2. A method for forming the superhard boron suboxide comprises mixing stoichiometric amounts of boron oxide (B.sub.2 O.sub.3) powder and boron powder and subjecting the mixture to a temperature of about 1800.degree. C. to about 2200.degree. C. and a pressure of about 2,000 to about 6,000 psi while encapsulated by boron nitride. The boron powder comprises about 90 to 95% by weight of elemental boron (B), and at least about 1% by weight of a sintering aid, such as Mg.

Abstract: An aqueous plastic composition of an inorganic powder which per se has substantially no plasticity which comprises: the inorganic powder and a polysaccharide of natural origin.The molding and sintering of the plastic composition provide a sintered body of high mechanical strength and dimensional accuracy.

Abstract: The dispersed ceramic composition for the manufacture of ceramic teeth, bridges and crowns in a dental technician's laboratory consists of a sinterable ceramic powder and a dispersing liquid and comprises a liquid consisting of a solution of from 0.05 to 5% by weight of one or more thickening agents from the group of cellulose, cellulose derivatives, tragacanth, xanthan gum and alginates in water, lower alcohols and/or other readily volatile organic solvents, while modifying additives may have optionally been added to said dispersed ceramic composition and the content of liquid is from 10 to 50% by weight of the ceramic composition.

Abstract: A living hard tissue replacement is prepared by superplastic forming a ceramic material which contains CaO, SiO.sub.2, and MgO, is substantially free of calcium phosphate, but capable of forming a calcium phosphate base compound upon contact with phosphorus-containing water. A replacement is also prepared by superplastic forming a sintered composite body comprising a calcium phosphate base ceramic matrix and an inorganic filler dispersed therein. Both the replacements are suitable as artificial dental roots and crowns.

Abstract: The present invention provides a method for preparing metal oxide powder. A first solution, which is substantially organic, is prepared. A second solution, which is an aqueous solution substantially immiscible in the first solution, is prepared and delivered as drops to the first solution. The drops of the second solution are atomized by a pulsed electric field forming micro-drops of the second solution. Reagents in the first solution diffuse into and react with reactants in the micro-drops of the second solution forming metal hydroxide or oxalate particles. The metal hydroxide or metal oxalate particles are then recovered and dried to produce the metal oxide powder. An apparatus for preparing a metal oxide powder is also disclosed.

Abstract: In a mold material for use in molding a titanium cast to be mounted into the mouth as a dental prosthesis, magnesia and phosphate are added as a binder to its main ingredient composed of alumina and zirconia.

Abstract: A process for producing a refractory material having the form TB.sub.o, e.g. zirconium nitride (ZrN), includes a first step of mixing a first salt having the form TX.sub.n, e.g. zirconium tetrachloride (ZrCl.sub.4) and a second salt having the form A.sub.m B, e.g. lithium nitride (Li.sub.3 N) in a ratio of n/m in a container. The process also includes a second step of igniting the mixture of the first and second salts, e.g. ZrCl.sub.4 and Li.sub.3 N, whereby the refractory material, e.g. ZrN, is produced along with byproducts having forms nAX and (n/m-o)B, e.g. 4LiCl and (1/6)N.sub.2, respectively. The process further includes a third step of separating the refractory material from the byproducts by solvent extraction. The stoichiometric ratio of the second salt to the first salt is n/m, e.g. 4/3. T is selected from the group consisting of transition metals, e.g. zirconium, and tetrelides, i.e. carbon, silicon, germanium, tin and lead.

Abstract: Conventional presintering and reaction presintering processes for the production of ceramic powders yield products exhibiting an undesired primary particle size distribution along with localized distribution of impurities, which give rise to the formulation of undesired duplex structures during final sintering.In order to avoid formation of undesired duplex structures within sintered ceramic parts a process and a device for producing ceramic powders based on single- or multi-phase metal oxides (including SiO.sub.2 - compounds), exhibiting a narrow particle size distribution, i.e. with a maximum deviation of the primary crystal size (REM) of +/- 0.75 .mu.m, preferentially less than +/- 0.25 .mu.m, within an average particle size of 0.05 up to 10.0 .mu.m, is conceived. The raw feed material exhibits a specific surface area of 0.05 up to 500 m.sup.2 /g (BET), preferentially 5.0 up to 50 m.sup.

Abstract: Microspherical sintered bodies of hydroxyapatite are prepared according to a new specific process wherein a suspension having hydroxyapatite microparticles dispersed in water or an organic solvent or a mixture of water and an organic solvent compatible therewith is atomized into a heating zone maintained above 500.degree. C. whereby spherical agglomerates of hydroxyapatite microparticles formed by drying and solidification of microdroplets of the suspension are sintered while the agglomerates are suspended in the heating zone. Microspherical sintered bodies of hydroxyapatite thus obtained, which may be modified by an optical heat treatment to adjust the surface area of the sintered body and growth of crystals therein, are useful in various fields of industry, for example, as a sorption agent in chromatographic separation.

Abstract: Novel ceramic filamentary micro-tubular materials are described. An entirely, fluid-phase method has been devised for producing such interwoven ceramic filamentary tubular materials. The process depends for its success the ability to generate a three-dimensional random weave of ceramic tubes, with diameters in the range of about 0.01 to 2.0 microns, by forming carbon filaments by catalytic decomposition of a hydrocarbon feed, coating the filaments with a ceramic coating and then oxidizing the coated filaments to remove the carbon core leaving behind hollow ceramic micro-tubular filaments. The ceramic micro-tubular materials may be free-standing porous structures and may have a variety of uses as thermal insulators, catalyst supports, superconductor supports, filters or as reinforcements for composites.

Abstract: It relates to calcium phosphate series compound ceramics in which heat-resistant inorganic short fibers such as flawless SiC or Si.sub.3 N.sub.4 are three-dimensionally dispersed in a matrix composed of calcium phosphate series compound and entangled with each other to form a high strength shaped body as well as a method of producing the same. And also, it relates to a high density silicon carbide ceramic in which biological glass is impregnated and filled in a porous shaped body, which provides composite ceramics having high strength and high toughness and suitable as a heat-resistant structural material or a material for bio hard texture.

Abstract: A ceramic material for use as artificial bone and dental root is provided which takes the form of a composite sintered body comprising crystalline calcium phosphate grains as a matrix and inorganic whiskers dispersed therein. An intermediate layer containing elements in either one or both of the whiskers and the grains intervenes between the whiskers and the grains. The material has physical toughness and strength as well as biomedical affinity. The material is prepared by mixing calcium phosphate and a whisker-forming material or whiskers and sintering the mixture at a temperature of 800.degree. to 1600.degree. C., followed by slow cooling to allow formation of the intermediate layer.

Abstract: A process for producing a bone prosthesis is disclosed, which process comprises the steps of: (a) adding granular ceramics to pullulan; and (b) treating the granular ceramics and the pullulan with high-temperature and high-pressure steam.

Abstract: A biologically active ceramic suitable as a substitute for hard tissues in a living body is disclosed, comprising a dense calcium phosphate ceramic body having formed thereon a surface layer mainly comprising at least one of hydroxyapatite and calcium tertiary .beta.-phosphate and having a surface roughness of from 10 to 1000 .mu.m. The surface layer is formed by forming a calcium phosphate coating containing hydroxyapatite and a phosphate or phosphate-containing glass capable of reacting with hydroxyapatite to form calcium tertiary phosphate on a calcium phosphate molded article or a sintered body thereof and calcining the calcium phosphate molded or sintered body with the calcium phosphate coating at a temperature of from 700.degree. to 1350.degree. C. to allow a part or the whole of the hydroxyapatite to react to form calcium tertiary .beta.-phosphate. The ceramic has improved bioaffinity and sufficient mechanical strength, and can be integrated into hard tissues in a reduced period of time.

Abstract: A manufacturing method for ceramic microspheres including the steps of; mixing an oil which is immiscible with an aqueous solution of a water-soluble metallic compound and which has a boiling point higher than that of water in the aqueous solution; applying ultrasonic vibration to the mixed solution to form a water-in-oil type emulsion; heating the emulsion at a temperature less than a boiling point of water to evaporate free water from droplets in which the water-soluble metallic compound is dissolved and to disperse spherical particles of the water-soluble metallic compound in the oil phase; and thereafter heating the dispersed solution at a temperature higher than the temperature at which the water-soluble metallic compound is decomposed to form a metallic oxide but lower than the temperature at which grain growth in the metallic oxide starts, to evaporate and decompose the oil and to remove the oil therefrom, thereby obtaining the metallic oxide microspheres.

Abstract: A cryogenic gyroscope for detecting the angular velocity of a rigid system without reference to an external inertial system comprises a closed rigid casing made of a sueprconducting material and kept below its critical superconducting temperature, for example, by immersion in a bath of liquid helium. A rotation-detector device is situated within the superconductor casing. This device, which is rigidly supported by the wall of the casing, includes at least one component of ferromagnetic material, constituted by a plurality of ferromagnetic strips intercalated with layers of electrically-insulating material.

Abstract: A method for forming extremely homogeneous metal and ceramic composites wherein a dispersion of metal and/or ceramic powders in a polymer solution, such as a solution of an organic binder, is precipitated by the addition of a second, miscible solvent in which the polymer is insoluble. The resulting precipitated second phase is compacted, dried and processed to form an extremely uniform composite with excellent physical properties. The method has advantages over other processes since it is relatively flexible and inexpensive yet yields a high quality product.

Abstract: Stable metal oxide sols comprising an anhydrous alcohol having metal oxide particles colloidally dispersed therein is disclosed. This sol composition is formed by the hydrolysis of a metal alkoxide to form metal oxide particles, removal of the particles from the resulting mother liquor from such a reaction, and the redispersing of the metal oxide powders in an anhydrous alcohol solvent.

Abstract: The invention disclosed by this application relates to a novel method of processing sinterable powders into sintered ceramic products. This application also relates to novel forms of aluminum oxide, hydroxylapatite, and tricalcium phosphate ceramic products prepared in accordance with the method of this invention, as well as novel intermediate products useful to prepare the novel ceramic products of this invention.

Abstract: A biomedical material for use as artificial bone and dental root is provided which takes the form of a sintered composite body comprising a crystalline calcium phosphate matrix and inorganic whiskers dispersed therein. The inorganic whiskers contain at least one oxide selected from the group consisting of silicon oxide, aluminum oxide, calcium oxide and magnesium oxide. The matrix of tricalcium phosphate or apatite preferably has a grain size of 0.05 to 30 .mu.m. The whiskers, typically anorthite and diopside whiskers occupy 0.5 to 95% by area of a cross section of the sintered body, and preferably have a length of 0.05 to 30 .mu.m and an aspect ratio of from 1.2 to 100, with the ratio of matrix grain size to whisker length being 10/1 to 1/10. The material has physical toughness and stength and biomedical affinity. The material is prepared by mixing calcium phosphate and a whisker-forming material or whiskers and sintering the mixture at a temperature of 800.degree. to 1600.degree. C.

Abstract: A porous ceramics material produced by the process comprising the steps of (i) mixing two or more ceramics in such a manner that at least one of the ceramics is different in sinterability from the others and is mixed in an amount of from 1 to 99 wt % based on the total amount of the ceramics; and (ii) sintering thus obtained mixture; a packing for chromatography comprising the porous ceramics material; and a process for producing the porous ceramics material.

Abstract: A method for molding ceramic powders comprises forming a slurry mixture including ceramic powder, a dispersant, and a monomer solution. The monomer solution includes at least one monofunctional monomer and at least one difunctional monomer, a free-radical initiator, and a aqueous solvent. The slurry mixture is transferred to a mold, and the mold containing the slurry mixture is heated to polymerize and crosslink the monomer and form a firm polymer-solvent gel matrix. The solid product any be removed from the mold and heated to first remove the solvent and subsequently remove the polymer, whereafter the product may be sintered.

Abstract: The present invention relates to a package adapted to house an electronic device, such as a semiconductor integrated circuit. The package components are comprised of aluminum based alloy. At least a portion of the surfaces of the package components are anodized to enhance corrosion resistance and increase bond strength. The aluminum based packages are characterized by lighter weight than copper based packages and better thermal conductivity than plastic based packages.

Abstract: A forming aid to be mixed in a ceramic material for forming the ceramic material into a formed ceramic body of a desired shape, including at least one of a thermoplastic resin and a wax, and a mineral oil in an amount of 30-95% by volume with respect to an entire volume of the aid. Also disclosed is a process of producing a ceramic article from the formed ceramic body containing the aid.

Abstract: A process for producing calcium phosphate ceramics having a porous surface is described, which comprise the steps of:a) preparing untreated calcium phosphate ceramics, which comprises a mixture of hydroxyapatite and tricalcium phosphate, andb) treating said untreated ceramics with an acidic solution to selectively dissolve the tricalcium phosphate in the surface of the ceramics.

Abstract: An implant material for replacing hard tissue of a living body is provided. The implant material comprises 10 to 90 wt % of a fiber glass and 90 to 10 wt % of an organic high polymer material. The fiber glass is mainly composed of calcium phosphate. The organic high polymer material does not inhibit affinity with the living body. On the surface of the implant material, a portion of the fiber glass is exposed.

Abstract: A composition comprising a ceramic material and, as a binder, poly(ethyloxazoline).

Abstract: A composition produced as a result of mixing alumina, silica, and a calcium phosphate compound in a specific ratio exhibits high affinity for bioceramics. When a bioceramic is coated with this composition and the coated bioceramic is heated, the composite is fused fast with the bioceramic to produce a composition bioceramic which is active to vital tissues.

Abstract: A ceramic article made from a mixture comprising (on a dry weight basis) magnesium oxide (MgO) in an amount up to 2% by weight, a defined rare earth oxide in amount up to 10% by weight, balance beryllium oxide, and trace elements, the defined rare earth oxide being zirconium oxide (ZrO.sub.2), hafnium oxide (HfO.sub.2), cerium oxide (Ce.sub.2 O.sub.3), yttrium oxide (Y.sub.2 O.sub.3), ytterbium oxide (Yb.sub.2 O.sub.3) or thorium oxide (ThO.sub.2). Such ceramic articles have much improved properties in particular higher densities than attainable hitherto and better crossbreak strength and surface smoothness as fired. The ceramic compositions can also be admixed with supplementary ceramic materials such as silicon carbide to produce microwave absorbing materials.

Abstract: Biomaterials useful for onthopedicanel dental applications is disclosed. These materials have a base portion of calcium carbonate and a surface layer of a synthetic phosphate such as hydroxyapatite. The base portion may be a calcium carbonate structure having three-dimensional interconnected porosity such as may be found in porous skeletal carbonate of marine life, e.g. coral porites skeletal aragonite, or it may be porous or non-porous granules of calcium carbonate.A method for making the biomaterials is also disclosed. The synthetic phosphate surface is made using a hydroconversion reaction with a soluble or solubilized phosphate such as ammonium dibasic phosphate ((NH4).sub.2 HPO4).

Abstract: An osteofiller is characterized by using columnar sintered hydroxy-apatite having at least one capillary tube passed therethrough in the vertical direction.

Abstract: A self-hardenable material comprising a calcium phosphate having an atomic ratio of Ca/P of 1.4 to 1.6, a difficultly water-soluble inorganic fluoride, an organic or inorganic acid and water is provided. For example, when the hardenable material is frilled in the form of slurry or paste in a necessary part in vivo or in the dental cavity, it hardens within a short time to form a stable apatite type product.

Abstract: The present process is a process for preparation of crystalline grains-oriented ceramics which comprises orienting grains of ceramics raw material powder to a definite direction by applying centrifugal force on the grains and then burning the resulting grains. These ceramics are expected to be utilized, for example, as .beta.- or .beta."-alumina solid electrolytes for use in sodium-sulfur cells and as magnetic anisotropic ferrite magnets for use in small-sized motors, speakers or the like.

Abstract: A method for producing a porous sintered apatite material comprising the steps of:sintering a calcium-excess apatite at 800.degree. C. or more so as to form a sintered apatite material having a calcium oxide content of from 0.5 to 60 wt % by phase separation of calcium oxide; andremoving the calcium oxide from the sintered apatite material so as to form a porous sintered apatite material.

Abstract: A slip or casting composition useful in molding or sheet casting comprising:a mixture of inorganic particulate material, an organic solvent and a dispersant for said particulate material having the structure set forth below: ##STR1## where R.sub.1, R.sub.2, R.sub.3 are linear or branched hydrocarbon chains, where no more than one of the R Groups is CH.sub.3 and the remaining R groups are each at least 6 to 30 carbon atoms long;Y is selected from the group consisting of (CH.sub.2).sub.n where n=1 to 10 and ##STR2## where m=1 to 5; and X is selected from the group consisting of COO-, SO.sub.3 -, PO.sub.3 -.

Abstract: This invention sets forth an agent for filling bone and tooth defects, for building up bone, for bone-contact layers and for the replacement of bones and the roots of teeth, which contains calcium phosphate apatite having carbonate and alkali portions, all ions being definedly integrated in the crystal lattice; use is optionally made together with additives and/or diluents both tolerated by the body. Furthermore, it sets forth the use of this apatite for filling bone and tooth defects, for building up bone, for bone-contact layers, as a replacement for bones and the roots of teeth and as an implant article consisting completely or partially of this apatite or consisting of a material known for implant articles and being coated completely or partially with a layer of this apatite.

Abstract: Dried emulsion of precursors for ceramic additives are added to paints containing fine particle ceramic materials for use in ceramic capacitors. The precursors are converted into the desired additives in the paints during the sintering of the capacitor bodies.

Abstract: Slurries or suspensions for forming sintered ceramic or metallic articles are described as having a high volume fraction of sinterable particles, at least 55% by volume. while the slurries maintain a pourable viscosity, such as not more that 2000 cPs at 100 s.sup.-1 ; the slurries can be dilatant and/or pseudoplastic. The slurries are prepared by using specific families of dispersants; namely acrylic acid-based polymeric polyelectrolytes, polyethylene imine-based polyelectrolytes, and coupling agents from the subfamilies of oxy-silane esters and phosphate esters. Fabrication of the compositions includes milling under high energy and the addition of at least a portion of the particles in a step-wise manner.

Abstract: A composition for use in forming a hard tissue substitute comprising (A) a powder ingredient mainly comprised of Ca.sub.n+2 (PO.sub.4).sub.2 O.sub.n-1, where n is from 1.9 to 4.9 and (B) an aqueous solution of an organic acid, preferably of the TCA cycle, or a polymer of an organic acid. This composition has a good affinity with living organisms, a high compressive strength, and a low disintegration rate.

Abstract: The ends of two composite superconductors (10a and 10b) having many filaments (12) are joined together to form a joint that is durable, superconducting under proper conditions, and has good shunting capacity. The filaments (12) are exposed by removal of the normal conducting matrices (14a and 14b) from the ends of the composite conductors (10a and 10b) to be joined. The superconductive filaments (12) from each of the composite conductors are inserted together into a sleeve (16) of bimetal construction. The inner surface (18) of the sleeve is made of superconducting material and is metallically bonded to the outer surface (20) of the sleeve which is made of normal conducting material. The bimetal sleeve (16) abuts the matrices (14a and 14b) of the composite conductors (10a and 10b) on one end, and the filaments (12) extend beyond the opposing end of the bimetal sleeve (16). The bimetal sleeve (16) is crimped to form a cold weld joint, and then severed in the region of the crimp to form another cold weld joint.

Abstract: Inorganic granules are characterized in that when the maximum extent of a granule is termed D and the dimension perpendicular to the maximum extent has a maximum extent termed A, A/D is 0.5 to 0.9; and in at least 80% of the granules, the position of A crossing with D is within 0.3D on either side of the center of D. Such granules can be obtained in a high yield by introducing inorganic powders capable of calcination into an organic porous body having a 3-dimensional net-like structure and subjecting the porous body to isotropic pressing thereby to form inorganic granules in pores of the porous body. The organic porous body is then burned off and at the same time, the inorganic granules are calcined. The inorganic granules are useful as bone fillers and the like.

Abstract: A process for preparing compound metal oxides, a superconductive compound oxides for instance, is disclosed. The process comprises preparing an aqueous solution containing a predetermined content ratio of chloride, nitrate or acetate of a rare earth metal, an alkaline earth metal and copper, slightly basifying the solution to form hydroxides of the rare earth metal and copper and then introducing carbon dioxide to form carbonate of the alkaline earth metal, collecting the thus formed mixed precipitate of hydroxides and carbonate and firing it.

Abstract: A highly loaded, uniform ceramic composite can be made by first preparing a highly loaded suspension. Due to the particle-particle interactions of a highly concentrated system, virtually any dopant can be added, including other suspensions, fibers, and whiskers. The process is particularly useful for making composites of materials which coagulate when mixed at low concentration.

Abstract: A process for the preparation of copper oxide superconductors which comprises (1) mixing and grinding yttrium nitrate hydrate, copper nitride, and an oxidizing agent such as barium peroxide in a suitable solvent; (2) forming a paste thereof; (3) applying the paste to a substrate; (4) heating the substrate with the paste thereon; and (5) therafter cooling. The process yields copper oxide superconducting compounds in a purity of at least 80 percent.

Abstract: A process for the preparation of copper oxide superconductors which comprises (1) mixing copper nitride, an oxidizing agent such as barium peroxide, and yttrium oxide; (2) forming pellets of the aforementioned mixture; (3) heating the pellets; and (4) thereafter cooling the pellets. The process yields copper oxide superconducting compounds in a purity of from about 60 to over 95 percent.

Abstract: Dental restorative compositions containing a mixture of Ca.sub.4 (PO.sub.4).sub.2 O and at least one different calcium phosphate.

Abstract: Compositions that are useful and unique as dental remineralizers and dental cements, as well as methods for their use, are disclosed. The compositions are mixtures of at least two sparingly soluble calcium phosphates that are present in excess and a dilute aqueous solution approximately saturated withThe invention described herein was made in the course of research partially supported by a grant from the National Institute of Dental Research.