Abstract:
A method of producing glass bodies having regions with different optical refraction, including a basic body and a coating layer which is sintered onto the basic body, covers the basic body at least partially and is made of glass, which as it is doped, has an index of refraction differing from that of the glass of the basic body. The starting material for producing the cladding on the basis of pulverulent ceramic material is deformed into a self-supporting, unsintered porous green body, is dried and submitted to a cleaning procedure in a heated gas phase. The coating layer to be bonded onto the basic body is melted into glass in a subsequent combined doping/sintering procedure in a gas phase containing the doping agent at a temperature in the range from 1150.degree. to 1500.degree. C. and is sintered onto the basic body.
Abstract:
An electrophotographic recording material having a porous layer of photoconductor-binder, particularly with crystalline tetragonal lead monoxide as the photoconductor, is provided between an electrically conductive layer and a dielectric foil, said pores of the layer of photoconductor-binder, prior to providing the foil, being filled with a high-ohmic dielectric liquid to wet both the layer of photoconductor-binder and the foil. Preferably, the pores of the layer are filled with tetramethyl tin as the photoconductor-binder. As a result of this, the use of an adhesive between the foil and the layer of photoconductor-binder may be omitted. A large porosity and hence a great sensitivity of the layer of photoconductor-binder are maintained.
Abstract:
Plasma-sprayed layers of aluminium oxide on a substrate are produced by using a pyrogenically produced aluminium oxide, for example selected from the group consisting of borosilicate and steel, as starting powder.
Abstract:
Plasma-sprayed layers of aluminium oxide on a substrate are produced by using a pyrogenically produced aluminium oxide, for example selected from the group consisting of borosilicate and steel, as starting powder.
Abstract:
The invention relates to a method for manufacturing optical glasses and colored glasses with the aid of a fluid phase sintering process from a basic material encompassing at least SiO.sub.2 powder as well as additives for reducing the temperature of the fluid phase sintering and/or melting process encompassing the following steps: the starting materials are dissolved in any sequence in a fluid medium to produce a solution as far as is possible and a suspension to the extent that they are not dispersed in solution; a greenbody is produced from the dissolved and dispersed starting materials; the greenbody is dried the dried greenbody is fluid-phase sintered at temperatures below 1200° C., in particular in the temperature range from 600° C. to 1200° C.
Abstract:
Plasma-sprayed layers of aluminium oxide on a substrate are produced by using a pyrogenically produced aluminium oxide, for example selected from the group consisting of borosilicate and steel, as starting powder.
Abstract:
Aqueous dispersion comprising silicon/titanium mixed oxide powder with a BET surface area of 5 to 500 m2/g which has been prepared by flame hydrolysis and has a titanium dioxide content of 0.5 to 20 wt. %, based on the powder, water and at least one pH-regulating substance which can be removed completely from the reaction mixture on heating, the aqueous dispersion having a solids content of between 40 and 80 wt. %. A green body produced therefrom with a green density of between 40 and 85%. A shaped glass article of optical quality with a coefficient of thermal expansion of not more than 0.5×10−6/K produced from the green body.
Abstract:
A method of drying ceramic green bodies, in which the green body is supported by a gas cushion and dried in a suspended position, while employing an arrangement comprising a filtering element which is adapted to the geometry of the green body to be dried, into which filtering element gas, preferably compressed air, can be introduced under pressure by a pipe supply. The gas issues from the filtering element's surface facing the green body to be dried through pore-like apertures which are envenly distributed over the whole surface where they form a gas cushion.
Abstract:
Method and equipment for the manufacture of glass bodies in which a porous green body is formed from the starting material for the glass body in the form of a thixotropic suspension, is dried, purified and then sintered, during which process the starting material is transformed into a state with minimum viscosity and homogenized by the introduction of mechanical forces, is poured in the low-viscosity state into a mould of hydrophobic material corresponding to the shape of the glass body to be manufactured and is dried in the mould until a shrinkage of approximately 10% is achieved and then, after removal from the mould, is subjected to further processing steps to produce the glass body.
Abstract:
Method and equipment for the manufacture of glass bodies wherein a porous green body is formed by extrusion from the starting material for the glass body in the form of a thixotropic suspension and this green body is then purified and sintered, during which process the starting material is brought in a state of minimum viscosity into an extruding press closed at its outlet end, is heated in the extruding press to a temperature below the boiling point of the dispersing liquid and then, after the extruding press is opened, is extruded into a green body of dimensionally stable shape by means of the die of the extruding press.