Abstract: Methods of impregnating various polymer substrates with an impregnation additive, by simultaneously contacting the polymer substrate with an impregnation additive, carrier liquid, and supercritical fluid are provided. The impregnation additive is substantially insoluble in the supercritical fluid, and the carrier liquid is preferably substantially insoluble in the supercritical fluid.

Abstract: A method of forming inorganic membranes which are highly selective to permeation of hydrogen by temporarily forming a carbon barrier in the pores of a porous substrate, followed by chemical deposition of SiO.sub.2, B.sub.2 O.sub.3, TiO.sub.2, Al.sub.2 O.sub.3 and mixtures thereof in the pores, followed by removal of the carbon barrier. It has been demonstrated that the permeation selective layers thusly formed by this invention have a five fold increase in permeance over such layers made by a similar method but without forming a temporary carbon barrier in the pores of the porous substrate, and removal of the carbon-barrier after establishment of the oxide membrane. Some suitable porous substrate are Vycor.TM. glass or Al.sub.2 O.sub.3.

Abstract: A method for protecting prostheses and temporarily or permanently implantable materials from bacterial colonization and infection, wherein the material is successively impregnated with: (a) a biguanide solution having the general formula (I) ##STR1## wherein R.sub.1 is an alkyl, aminoalkyl, optionally substituted phenyl, naphthyl or cyano radical, R.sub.2 is a hydrogen atom or an alkyl radical and n is an integer from 1-6, with the proviso that the alkyl radicals and portions are linear or branched and contain 1-4 carbon atoms; and (b) a solution of an antibacterial agent which may be gradually redistributed in an aqueous medium; whereafter the material thereby impregnated is dried.

Abstract: A process for producing a nitrogen-alloyed stainless steel layer on steel by applying nitride containing mixed metal powder or stainless powder to the steel surface, and thereafter treating the steel with laser beams.

Abstract: Disclosed is a method of forming metal containing ceramic coatings on substrates. The method comprises applying a coating of hydrogen silsesquioxane resin and a metallic filler onto a substrate and heating the coated substrate at a temperature sufficient to convert the hydrogen silsesquioxane resin to a silica containing ceramic matrix containing the metallic filler.

Abstract: For providing a molded catalyst or a supported catalyst which has an excellent mechanical strength and is intended for producing methacrolein and methacrylic acid from isobutylene or tertiary butanol, the surface of a molded catalyst or a supported catalyst which contains molybdenum, bismuth and iron is coated with one or more highly depolymerizable organic high-molecular weight compounds.When used, the catalyst is packed into a reactor and then heated to remove the organic high-molecular weight compound(s) by depolymerization.

Abstract: A method of producing activated carbon supported on a substrate involves impregnating a substrate with a crosslinking resin curing catalyst, followed by impregnating the substrate with a crosslinking thermosetting resin, curing the resin, carbonizing the resin, and activating the carbon.

Abstract: Methods of making sustained release bactericidal cannulas or catheters through which aqueous biological fluids can pass. The bactericidal cannula for catheter including a tube having an inner surface, defining and interior lumen, and an outer surface. The tube has a polymeric matrix and antibacterial agent residing within at least a portion of the polymeric matrix. The polymeric matrix includes cured silicon rubber and the antibacterial agent is a finely divided nitrofuran compound which is soluble in water and effective to prevent proliferation of certain bacteria in an otherwise growth supporting aqueous environment when dissolved in the aqueous environment to the limit of its solubility therein at 37.degree. C. The solubility of the nitrofuran compound is about 0.2% by weight or less at a pH of about 6 and a temperature of about 25.degree. C.

Abstract: A method for producing composite materials by introducing additional phases into a porous body wherein a liquid precursor is infiltrated into the porous body, the liquid is decomposed to produce a desired phase, the body is fired for further densification, and the decomposed liquid is allowed to remain as an additional phase or reacts with the porous body to form an additional phase is disclosed. This allows for a novel method of introducing the additional phase, and by controlling the parameters such as infiltration time, firing schedule, porous body density, etc., the size, amount, extent and distribution of the added phases may be controlled.

Abstract: Method for making a component, graphite component, such as a graphite crucible, for use in the production of silicon crystal growth from molten silicon wherein the graphite component has an outer coated layer of glassy carbon formed from a thermoset organic resin that prevents contamination of the molten silicon by carbon from the graphite component.

Abstract: This invention provides a shaped ceramic composite article comprising ceramic oxide fiber(s), a first coating comprising a carbonaceous matrix which includes boron nitride particles in contact therewith, and a second coating comprising silicon carbide. The inventive composite article is useful in applications requiring good heat resistance and mechanical properties, such as gas fired radiant burner tubes, gas burner nozzle liners, heat exchangers, thermowells, core busters or flame dispersers, and other gas fired furnace components.

Abstract: Polymeric implants provided with coatings of bactericidal compounds in the form of ionized atoms by a vapor process. The polymeric implants include products designed to penetrate or enter the body, such as catheters, shunts connectors and the like. Coatings of bactericidal compounds on the polymeric implants are intended to make their use safe. The coatings are formed thereon in the form of ionized atoms of the compounds by ion-beam-assisted deposition in a vacuum chamber. The vacuum chamber is provided, inter alia, with an evaporator and an ion source mounted in operative association therein, including means for rotatably mounting a plurality of polymeric implants for exposure to the evaporator and the ion source.

Abstract: A method for making an intravascular stent by applying to the body of a stent a solution which includes a solvent, a polymer dissolved in the solvent and a therapeutic substance dispersed in the solvent and then evaporating the solvent. The inclusion of a polymer in intimate contact with a drug on the stent allows the drug to be retained on the stent during expansion of the stent and also controls the administration of drug following implantation. The adhesion of the coating and the rate at which the drug is delivered can be controlled by the selection of an appropriate bioabsorbable or biostable polymer and the ratio of drug to polymer in the solution. By this method, drugs such as dexamethasone can be applied to a stent, retained on a stent during expansion of the stent and elute at a controlled rate.

Abstract: A nonflammable composition that is useful for applying silicone lubricants to the surfaces of medical articles is described. The composition includes a highly fluorinated organic compound, a fluorine-free solvent, and a silicone lubricant.

Abstract: There is provided according to the invention a method for producing a composite material mainly composed of a carbon and boron comprising the steps of impregnating a carbon material with a boron oxide and/or a hydrate compound thereof, and baking such carbon material under pressure by inert gas at a temperature of not lower than 1500.degree. C. A neutron absorbent and an oxidation resistant carbon material both including the composite material are also provided.

Abstract: A p.sup.+ -diffusion layer is formed on a surface of a p-type silicon substrate in self-alignment with a groove 7 defined in the p-type silicon substrate, and a thin insulating film is formed on the groove and the p.sup.+ -diffusion layer in self-alignment therewith, the thick insulating film having side walls. A self-aligned n.sup.+ -diffusion layer has terminal edges spaced from terminal edges of the p.sup.+ -diffusion layer for minimizing any leakage current flowing between these terminal edges.

Abstract: (1) A carbon film derived from a polyimide film, which has a tensile strength of at least 15 Kgf/mm.sup.2, a tensile modulus of elasticity of at least 5000 Kgf/mm.sup.2 and an electric conductivity of at least 200 S/cm.(2) A process for preparing a carbon film which comprises the following steps:1) reacting a monomer combination selected from the group consisting of a combination comprising a tetracarboxylic acid dianhydride and an aromatic diamine and a combination comprising a tetracarboxylic acid dianhydride, an aromatic diamine, and a polyamino compound having at least three amino groups to form a polyamic acid;2) forming a film of polyamic acid;3) imidizing the polyamic acid film to form a polyimide film having a tensile strength of at least 10 Kgf/mm.sup.2 and a tensile modulus of elasticity of at least 500 Kgf/mm.sup.2 ; and4) carbonizing the polyimide film in an inert gas or in a vacuum until a carbon film having a tensile strength of at least 15 Kgf/mm.sup.

Abstract: A medical device is coated with a solution of TDMAC heparin and then allowed to air dry. Thereafter, the coated medical device is exposed to gamma ray radiation. The gamma radiation strengthens the bond of the TDMAC to the material of the medical device. In a variation of this method, TDMAC heparin coated and gamma ray irradiated medical device is heated for an extended period of time. This heating has been found to further strengthen the bond of the TDMAC heparin to the medical device.

Abstract: Disclosed is a method for forming improved Si--0 containing coatings on electronic substrate. The method comprises treating Si--0 containing ceramic coatings derived from hydrogen silsesquioxane resin with hydrogen gas. The resultant coatings have improved properties such as stable dielectric constants.

Abstract: The present invention relates to a method of forming coatings on electronic substrates and the substrates coated thereby. The method comprises applying a coating comprising a borosilazane and a filler on a substrate and heating the coated substrate at a temperature sufficient to convert the borosilazane to a ceramic coating.

Abstract: The present invention relates to a method of forming protective coatings on electronic substrates and the substrates coated thereby. The method comprises applying a coating comprising a polysilazane and a filler on a substrate and heating the coated substrate at a temperature sufficient to convert the polysilazane to a ceramic.

Abstract: A mandrel for making a rigid tubular article that has integrally-formed straight and arcuate portions. The mandrel has a plurality of shape-providing elements slidably disposed on interconnected straight and arcuate rods. After a rigid tubular article has been formed about the mandrel, the shape-providing elements can be slid off the straight and arcuate rods so that the mandrel can be removed from the rigid tubular article's interior. This provides for easy separation of the mandrel from the tubular article.

Abstract: A process is described for producing carbon bodies and a coating of silicon-infiltrated silicon carbide. In this process, the surface of carbon bodies is coated with an aqueous slip containing finely divided silicon carbide and binder. The coating is then dried and the binder is decomposed by heat. The coated carbon bodies are then silicized at their surface by contact with liquid silicon.

Abstract: A method of producing an article with a coating having friction-reducing properties in wet condition, the coating including a binder (a), a hydrophilic polymer (b), as well as an osmolality-increasing compound (c), where the osmolality-increasing compound (c) is applied in a condition different from a water-based dissolved condition, preferably in a non-dissolved, solid condition, as well as an article with a coating having friction-reducing properties in wet condition, the coating comprising a binder (a), a hydrophilic polymer (b), and an osmolality-increasing compound (c) in form of particles of a size of maximum 50 .mu.m. The method can be performed in a simple and fast manner without involving a time-delaying evaporation of water, and the article is remarkable for the osmolality-increasing compound being uniformly dispersed in the coating.

Abstract: A method of forming an oxidation resistant aluminum coating on a carbon-carbon composite comprising applying a slurry over the carbon-carbon composite, composed of an aluminum intermetallic in a liquid suspending vehicle including a high char yield adhesive thermoplastic and a glassy carbon, distributing aluminum, in elemental form, over the coated surface and reacting the composite and coating in a furnace.

Abstract: A process for producing a cutting tool includes the steps of subjecting a sintered body to a nitrogen gas pressure treatment conducted under a pressure ranging between 0.2 and 10 MPa and at a temperature between 900.degree. C. to 1300.degree. C. for a period of at least 0.5 hours, evacuating a protective gas at a pressure between 10 Pa and 20 kPa at temperatures between 1000.degree. C. and 1350.degree. C. over more than 0.5 hours before the sintered body is cooled under a pressure between 10 Pa and 0.1 Pa, thereby forming a binding layer and treating a metal base body with CVD or PVD or plasma activated CVD for coating the metal base body with the binding layer.

Abstract: A process of manufacturing carbon fibers of high chemical stability comprises reacting feed carbon fibers having an elastic modulus of 30.times.10.sup.3 kgf/mm.sup.2 with a compound of elements capable of forming a carbide ceramics on the carbon fibers peripherally alone or both peripherally and partially internally.

Abstract: Disclosed is a method of forming opaque coatings on integrated circuits. The method comprises selectively applying a coating of a silica precursor resin and a filler onto the integrated circuit and heating the coated circuit at a temperature sufficient to convert the silica precursor resin to a silica containing ceramic matrix.

Abstract: In accordance with the invention there is provided a method of producing a densified carbon preform having interior a porous region of graded carbon-silicon carbide, carbon-silicon nitride or ceramic-ceramic composition.

Abstract: A process for detecting any defect in a ceramic body, including the steps of forming an electrically conductive layer in any such defects including fine voids present in the ceramic body, and then detecting presence or absence of the defect by measuring electrical conductivity between two given points shorted by the electrically conductive layer. The electrically conductive layer may be formed by penetrating an electrically conductive liquid into the defect. Alternatively, the electrically conductive layer may be formed by penetrating a penetrable liquid capable of forming the electrically conductive layer by thermal treatment or chemical treatment and thermally or chemically treating same.

Abstract: A porous preform is densified by heating while emersed in a precursor liquid. Heating is achieved by passing a current through the preform or by an induction coil immersed in the liquid. Ways to control the densification process are also described.

Abstract: Disclosed is a method of forming high dielectric constant coatings on substrates. The method comprises applying a coating of hydrogen silsesquioxane resin and a high dielectric constant filler onto a substrate and heating the coated substrate at a temperature sufficient to convert the hydrogen silsesquioxane resin to a silica containing ceramic matrix containing the filler.

Abstract: For the manufacturing of an oxidation-stable component that can withstand temperature changes for space travel, a solid CFC-body with a density of from 0.1 to 0.8 g/cm.sup.3, which has nondirectional short fibers, is made from short carbon fibers and a hardenable resin binder. From the solid CFC-body, a CFC-blank having the dimensions of the component to be manufactured is prepared by means of turning or other material cutting. The CFC-blank is infiltrated with pyrolytic carbon to a density of no more than 1.0 g/cm.sup.3 and then with metallic silicon so that its density amounts to more than 2.0 g/cm.sup.3. A portion of the metallic silicon is reacted with the pyrolytic carbon to form silicon carbide. The proportion of the unreacted metallic silicon which remains in the component after this reaction amounts to at least 15 percent by weight.

Abstract: A structural part made of carbon-carbon composite with a matrix surface-treated with SiC, resistant to oxidation and a process for manufacturing it.According to the invention, the structural part has a fibrous preform (2) composed solely of carbon fibers (4) immersed in a matrix (6) of carbon whose porosities (7, 8) contains ultrafine crystalline SiC powder (10) that serves as a gaseous diffusion barrier. The quantity of crystalline SiC powder is 5% to 30% by weight of the preform-matrix-powder unit. This part can resist up to 1700.degree. C. without external protection against oxidation.

Abstract: The present invention relates to a method of forming a homogeneous ceramic coating on a substrate. The method comprises depositing a preceramic coating on a substrate and then heating the substrate while directing a stream of cooling gas at the surface of the preceramic coating such that a temperature gradient is developed in the coating. This temperature gradient is created in such a way that the preceramic material near the substrate is converted to its ceramic form while the preceramic material near the surface of the coating is deterred from conversion. The temperature gradient is then decreased over time such that all of the preceramic material ceramifies from the substrate outward to form a homogeneous coating on the substrate.

Abstract: Disclosed is a method for the formation of ceramic silicon oxide films on substrate surfaces wherein said films are thick, free of cracks and pinholes, and insoluble in organic solvents. These films are formed by coating the surface of a substrate with a silicon resin having the general formula(HR.sub.2 SiO.sub.1/2).sub.X (SiO.sub.4/2).sub.1.0wherein R is selected from the set comprising the hydrogen atom, alkyl groups, and aryl groups, and 0.1.ltoreq.X.ltoreq.2.0, and then heating the coated substrate to convert the coating into a ceramic silicon oxide film.

Abstract: This invention discloses a method for subjecting a carbon/carbon composite material to strain at high temperature which permits the resulting composite material to be formed into various shapes.

Abstract: A carbon composite material reinforced with a carbon fiber and an inorganic fiber. The composite material has a core formed of a carbon fiber-reinforced carbon composite comprising a carbon fiber reinforcement and a carbon matrix, The core is externally covered with an inorganic fiber-reinforced carbon composite comprising an inorganic fiber reinforcement, other than carbon, and a matrix composed either of carbon alone or a mixture of carbon and boride. This provides for sound and steady protection against oxidation, as well as for retention of high strength in an oxidizing atmosphere at high temperatures.

Abstract: A silica coating is formed on an electronic substrate by applying a silazane polymer on the substrate and converting it to silica by heating in an oxidizing environment. The resultant thick planarizing coatings are useful as protective coatings and dielectric inner layers.

Abstract: There is provided a method for producing a carbon material coated with carbon film comprising the steps of dissolving an aromatic polyamide imide resin in an organic solvent to obtain a solution, applying this solution to a carbon material or impregnating the carbon material with the solution, curing the material at 300 to 400%, and carbonizing and/or graphitizing the material by baking under non-oxidizing atmosphere. There is also provided a carbon material coated with an amorphous carbon film which is a product of thermal decomposition of aromatic polyamide imide.

Abstract: A method of densifying a porous substrate by means of a matrix containing carbon, for obtaining an article made of a composite material, the method comprising the following steps:providing on one side of a substrate to be densified a slip containing submicron carbon powder;establishing a pressure difference to force the slip through the substrate;filtering the liquid that has passed through the substrate to retain the carbon powder inside the substrate; andwhen densification of the substrate by means of the carbon powder has terminated, drying the densified substrate and transforming a carbon precursor introduced into the substrate into carbon by carbonization, thereby binding the powder constituting the matrix.

Abstract: Porous solid bodies, especially carbon bodies, are densified by chemical vapor deposition by establishing a thermal gradient within the body, thermally decomposing a gaseous precursor so deposit an electrically and thermally conductive deposit (e.g. carbon) within the body, and shifting the thermal gradient toward the lower temperature zone as deposition proceeds, by means of induction heating.

Abstract: Methods of impregnating various polymer substrates with an impregnation additive, by simultaneously contacting the polymer substrate with an impregnation additive, carrier liquid, and supercritical fluid are provided. The impregnation additive is substantially insoluble in the supercritical fluid, and the carrier liquid is preferably substantially insoluble in the supercritical fluid.

Abstract: A fiber preform is initially consolidated by being impregnated with a thermosetting impregnation composition that contains a ceramic precursor, and by heat treatment at the end of which the precursor has been transformed into ceramic, without passing through a meltable phase. The consolidated preform is then densified. The impregnation composition is constituted by a mixture of a thermosetting monomer and a ceramic precursor polymer, and the monomer is cross-linked during the heat treatment so as to achieve "in situ" cross-linking of the polymer mixture prior to transforming the precursor into ceramic.

Abstract: The present invention provides a novel enamel composition and a method of using the same to decorate substrates such as a section of glass. The enamel composition comprises a solids portion and a vehicle. The solids portion includes at least one glass frit and a separate and distinct addition of silicon. The solids portion comprises from about 0.01 weight percent to about 20 weight percent metallic silicon.

Abstract: The present invention is directed to a process for coating carbon fibers with a pitch material. The process employs a pressurized air-comb for spreading a carbon fiber tow into individual carbon fiber filaments and providing the carbon fiber filaments in a spreaded tow to a powder deposition chamber. A pitch material is dried and finely ground and is then fed into the coating chamber at a point above the traveling spreaded carbon fiber tow. The pitch powder initially falls onto the fiber tow and begins forming a uniform coating around the individual carbon fibers. After falling past the point of the traveling carbon tow, the pitch powder is then recirculated back to the upper portion of the coating chamber and is entrained within a pitch powder cloud through which the threaded fiber tow travels. Fibers that are coated by such a method may be used to form carbon/carbon composites that exhibit high strength and excellent mechanical properties.

Abstract: Disclosed is a method for forming improved Si--O containing coatings on electronic substrate. The method comprises converting hydrogen silsesquioxane resin into a Si--O containing ceramic coating in the presence of hydrogen gas. The resultant coatings have improved properties such as stable dielectric constants.

Abstract: The present invention provides linear organosilicon polymers including acetylene and vinylene moieties, and a process for their preparation. These diorganosilacetylene-alt-diorganosilvinylene linear polymers can be represented by the formula: --[--(R.sup.1)(R.sup.2)Si--C.tbd.C--(R.sup.3)(R.sup.4)Si--CH=CH--].sub.n-- , wherein n.gtoreq.2; and each R.sup.1, R.sup.2, R.sup.3, and R.sup.4 is independently selected from the group consisting of hydrogen, halogen, alkyl, alkenyl, aryl, and aralkyl radicals. The polymers are soluble in organic solvents, air stable, and can be pulled into fibers or cast into films. They can be thermally converted into silicon carbide ceramic materials.

Abstract: A novel method is disclosed for the preparation of a silicon carbide-based composite ceramic body reinforced with carbon fibers having an outstandingly high mechanical strength. The method comprises impregnating carbon fibers with a mixture of fine silicon particles and a thermosetting resin such as a phenolic resin to give a carbon fiber compact body impregnated with the mixture, which is then subjected to a heat treatment at about 1400.degree. C. in an inert atmosphere so that the thermosetting resin is thermally decomposed to produce free carbon capable of reacting with the silicon particles without affecting the carbon fibers embedded in the matrix due to the preferential reactivity of the silicon particles with the free carbon produced from the resin thus not to decrease the recinforcing effect of the carbon fibers.

Abstract: A method of making a composite article and a composite article specifically adapted for use in high temperature, corrosive and errosive environments comprising a carbon fibrous substrate, including a pyrolytic carbon sheath formed about each fiber of the substrate; a metallic carbide, oxide, or nitride compliant coating over the coated fibers of the substrate; and an impermeable metallic carbide, oxide or nitride outer protective layer formed about the entire periphery of the coated substrate. In accordance with the method of the invention, the compliant metallic coating is applied to the fibers in a manner such that any mechanical stresses built-up in the substrate due to a mismatch between the coefficient of thermal expansion of the fibrous substrate and the coating are effectively accomodated.