Abstract: Ultra-low thermal expansion TiO.sub.2 --SiO.sub.2 glasses are prepared using a sol-gel process wherein a stable alkali silicate solution comprising colloidal TiO.sub.2 and having a pH above 9 is gelled to form a semisolid silicate gel, the gel comprising homogeneously dispersed colloidal TiO.sub.2 but being essentially free of agglomerated TiO.sub.2 particles, washing the gel with aqueous media to remove alkali therefrom, and finally drying and consolidating the gel to a clear, void-free TiO.sub.2 --SiO.sub.2 glass which is substantially free of compositional inhomogeneities and has a thermal expansion coefficient below that of pure fused silica.

Abstract: Porous, hollow, silica-rich fibers with good alkaline tolerance are produced from hollow glass fibers of an alkali metal borosilicate glass having one or more oxides of a metal of Group IV of the Periodic Table in an amount of about 1 to about 20 weight percent of the glass composition. The hollow porous silica-rich fibers are produced by acid leaching where the hollow glass fibers have greater than 25 weight percent extractable components, less than 25 weight percent extractable components but a wall thickness of less than 15 microns, or less than 25 weight percent extractable components and a fiber diameter of less than 25 microns. In addition, heat treating can be used for hollow glass fibers having greater than 25 weight percent extractable components to enlarge the pores.

Abstract: A chemically durable porous glass of which the skeleton mainly comprises SiO.sub.2 -ZrO.sub.2 system glass having a ZrO.sub.2 content of 2 or more wt %, and a process for the production of such glass.

Abstract: A liquid containing radioactive ions is purified (decontaminated) by contacting the same with an inorganic ion exchange composition having ion exchange sites which can be occupied by the radioactive ions from the liquid. The ion exchange composition is a mixture of an ion exchange medium and an additive which is relatively inert to the ion exchange process and which is a sintering aid for the ion exchange medium designed to lower the sintering temperature of the ion exchange composition. The ion exchange composition may be disposed within a suitable container (e.g., cannister), e.g., made of 304L stainless steel or Inconel 601 and the ion exchange process may be carried out in such container. Alternatively, the ion exchange medium can be employed without being previously admixed with the additive. The additive, if desired, can be admixed at a later stage with the contaminated medium.

Abstract: Optical glasses based on silica and alumina, rich in modifying metals such as silver, thallium and cesium. The exchange by cathodic migration in a melted salt bath of said modifying metals by metals such as K, Na and Li, exchange which leads to a corresponding variation of the refraction index of the glass according to a certain predetermined profile, is performed very efficiently and rapidly. Such an exchange is performed either on the finished glass or on a microporous form thereof.

Abstract: This invention relates to the production of transparent, high silica glass envelopes for tungsten-halogen lamps consisting essentially, by weight, of 1-2.5% Al.sub.2 O.sub.3, 0.25-1% CaO, 0.1-0.25 Na.sub.2 O and/or K.sub.2 O, 2.5-3.5% B.sub.2 O.sub.3, 0.15-0.3% F, and the remainder SiO.sub.2.

Abstract: A liquid containing radioactive ions is purified (decontaminated) by contacting the same with an inorganic ion exchange composition having ion exchange sites which can be occupied by the radioactive ions from the liquid. The ion exchange composition is a mixture of an ion exchange medium and an additive which is relatively inert to the ion exchange process and which is a sintering aid for the ion exchange medium designed to lower the sintering temperature of the ion exchange composition. The ion exchange composition may be disposed within a suitable container (e.g., cannister), e.g., made of 304L stainless steel or Inconel 601 and the ion exchange process may be carried out in such container. Alternatively, the ion exchange medium can be employed without being previously admixed with the additive. The additive, if desired, can be admixed at a later stage with the contaminated medium.

Abstract: A method for manufacturing the insulating layers of a glass multilayer wiring board from a mixture of (1) 30-90 wt. % of a borosilicate glass consisting of 55-75 wt. % of SiO.sub.2, 13-25 wt. % of B.sub.2 O.sub.3, 5-13 wt. % of Al.sub.2 O.sub.3, each 1-5 wt. % of PbO, MgO, and BaO, and each 1-2 wt. % of Na.sub.2 O and K.sub.2 O and (2) 70-10 wt. % of a silica glass, is provided.

Abstract: Quartz glass includes iron and aluminum. The total iron content ranges from 0.01 to 5% by weight, and the total aluminum content ranges from 0.01 to 10% by weight. The quartz glass exhibits infrared rays-absorbing ability and visible light-transmitting ability. Also a process for making such a quartz glass is disclosed.

Abstract: Optical components using a germania-silica glass are made by a gel technique. Tetra pentyloxygermane and a silicon alkoxide are hydrolyzed to form a gel, which is subsequently dried. Optical components, including optical fibers and devices, can be made using glass prepared by this technique.

Abstract: What is disclosed is a method of preparing carbon-containing monolithic glassy ceramics from organosilsesquioxanes, metal oxides and metal alkoxides through pyrolysis of their gels. Also disclosed are certain gel compositions used in the method and the glassy ceramics.

Abstract: A fabrication technique is described for making various devices in which a type of glass is used as a surface protection layer. The glass layers are put down by particle bombardment (generally sputtering) of a borosilicate glass target. Devices with such surface layers are also described. Such glass layers are highly advantageous as encapsulating material, diffusion barrier layers, etc., particularly for optical type devices and certain semiconductor devices. Particularly important is the preparation procedure for the glass target used in the bombardment process. The glass layers are moisture stable, act as excellent barriers against diffusion, and are usable up to quite high temperatures without cracking or peeling. The glass layers also provide long-term protection against atmosphere components including water vapor, oxygen, atmosphere pollution contaminants, etc.

Abstract: A process is described for making a doped-silica ingot useful in the manufacture of optical fibers. At least a silicon compound and a titanium compound are decomposed in the flame of the induction plasma burner in the presence of a determined supply of hydrogen and are reacted with the oxygen contained in the burner feed gas and/or in the vector gas to form SiO.sub.2 and H.sub.2 O against a heat-stable support. As a result silica and titanium oxide are deposited on the support in the form of a homogeneous vitreous mass exhibiting a selected concentration of hydroxyl groups between 10 and 50 parts per million. Fluorine-doped silica is deposited radially in the same way on the resulting ingot. The resulting semifinished product is a cylinder consisting of a titanium-doped silica core, whose TiO.sub.2 concentration by weight is about 0.1 to 8%, covered by a sheath of fluorine-doped silica, whose fluorine concentration is about 0.1 to 3%.

Abstract: A quartz glass lamp vessel 1 or 21 is used in many types of lamps. Sometimes it is expedient to absorb a certain portion of the emission spectrum. In accordance with the prior art this is possible by including rare earth metal oxides in the quartz glass.The solubility of rare earth metal oxides in quartz glass is, however, limited.According to the invention, quartz glass is used which contains an alkali metal oxide and optionally, an alkaline earth metal oxide, in addition to a rare earth metal oxide. The alkali metal oxide increases the solubility of the rare earth metal oxide, so that rare earth metal oxides can be used in larger concentrations. This results in glasses which have a higher degree of absorption, from which lamp vessels can be produced.

Abstract: Magnetic materials exhibiting ferrimagnetic and/or superparamagnetic behavior, produced by impregnating porous glasses with iron and, optionally, manganese, cobalt and nickel compounds, reacting the compounds with the porous glass to form bound complexes, heating the glass to expel unreacted organometallics, and further heating to convert the bound complexes to ferrimagnetic and/or superparamagnetic oxide crystallites, are described. Ferrimagnetic iron oxide crystallites exhibiting coercivities above 10,000 Oe can be made.

Abstract: In optical glass fibres formed of high-silica glass which is susceptible to the production of color centers on drawing into fibres, the attenuation due to such drawing-induced color centers is suppressed or reduced by incorporating from 1 to 100 (preferably 3 to 50) parts per million of cerium oxide in the glass from which the fibre is drawn, under oxidizing conditions such that a significant proportion of the cerium is in the form of ceric ions and the total attenuation is not more than 20 dB/Km in the wavelength range from 800 to 900 nm.

Abstract: A method of manufacturing gel powder suitable for use as a starting material in the manufacture of hollow glass microspheres having a high concentration of silica. The powder is manufactured from a gel containing boron in the amount of about 1% to 20% (oxide equivalent mole percent), alkali metals, specifically potassium and sodium, in an amount exceeding 8% total, and the remainder silicon. Preferably, the ratio of potassium to sodium is greater than 1.5.

Abstract: Doped quartz glass is produced by fusing a mixture of quartz powder with a concentrate. The concentrate consists of quartz powder and the oxides of alkaline earth metals and/or alkali metals (dopants). By adding a small quantity of dopants, a doped quartz glass can be obtained having a viscosity behavior corresponding to that of Vycor glass. Still softer glasses can be obtained by the addition of some more dopants.

Abstract: A method for producing optical glass, which comprises charging a mixed solution capable of forming a high-silica-content gel by hydrolysis reaction into a vessel, the inner wall face of which is composed of a material unwettable to the mixed solution, such as a fluorocarbon resin or silicone resin, causing gelation of the mixed solution in the vessel, drying the obtained gel, and heating and sintering the obtained dry gel. When electrodes are placed in the mixed solution at the gelation step and an electric voltage is applied, the time required for formation of the gel is shortened. Furthermore, at the gel-drying step, if the amount of materials evaporated from the gel is detected or the weight of the gel is measured, the detected amount of the evaporated materials or the change of the weight of the gel is fed back to a factor regulating the drying speed, such as the drying temperature to control the drying speed to an appropriate level.

Abstract: A method for producing silica glass wherein a dry silica gel subjected to a water desorption treatment and a carbon removal treatment is heated and has its temperature raised in an atmosphere containing chlorine, to perform a hydroxyl group removal treatment, the resultant silica gel is thereafter heated to a temperature of approximately 1,000.degree. C.-1,100.degree. C. in an atmosphere containing at least 1% of oxygen, to perform a chlorine removal treatment, and the resultant silica gel is further heated to a temperature of 1,050.degree. C.-1,300.degree. C. in He or in vacuum, to perform a sintering treatment. The silica glass thus produced does not form bubbles even when heated to high temperatures of or above 1,300.degree. C. Therefore, it is easily worked and it is free from the lowering of transparency attributed to the bubble formation.

Abstract: Luminescent material may be fabricated of silicon dioxide containing as activators approximately up to 1% monovalent copper together with up to approximately 15% aluminum. The material may be in powder form, it may be in glass form or it may be produced by electrolytic ingredient transfer. The material is luminescent in the blue range from 380-580 nanometers.

Abstract: What is disclosed is a method of preparing carbon-containing monolithic glassy ceramics from organosilsesquioxanes, metal oxides and metal alkoxides through pyrolysis of their gels. Also disclosed are certain gel compositions used in the method and the glassy ceramics.