Abstract: A yellow color by transmitted light is produced in a high silica glass by impregnating a porous, high silica glass with a solution of chromium and zinc salts and consolidating the glass under oxidizing conditions to dope the glass with chromium and zinc oxides, the chromium being predominantly in the hexavalent state. Optionally, an aluminum salt is included in the impregnating solution. The glass has particular utility as a filter for lighting purposes.

Abstract: A yellow color by transmitted light is produced in a high silica glass by impregnating a porous, high silica glass with a solution of chromium and zinc salts and consolidating the glass under oxidizing conditions to dope the glass with chromium and zinc oxides, the chromium being predominantly in the hexavalent state. Optionally, an aluminum salt is included in the impregnating solution. The glass has particular utility as a filter for lighting purposes.

Abstract: There is disclosed a method of dewatering porous 96% silica glass by impregnating the glass pores with an aqueous solution of a water-soluble, nitrogen-containing, organic compound that is thermally decomposable to produce reactive gaseous nitrogen species, and then thermally decomposing the impregnating compound to yield nitrogen which combines with the glass to oust hydroxyl group. A preferred material is guanidine hydrochloride, and a non-oxidizing atmosphere is maintained during heating to avoid nitrogen oxidation. The nitrided porous glass may subsequently be thermally consolidated to a non-porous body.

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: An electrochromic device comprising a solid electrolyte, wherein the electrolyte consists of porous glass impregnated with a solid ion-conductive compound such as an alkali metal salt, is described.

Abstract: There is disclosed an improved integral optical device of the type produced by creating optical patterns in porous glass bodies, especially patterns involving gradient refractive index distributions. The optical strength of an element, such as a lens, in such an optical pattern is increased by treatment with a polymerizable, organo functional silicone fluid while the matrix glass is sealed.

Abstract: A method for providing a dispersion of a photosensitive silver and chlorine-containing polyphosphate in the pores of a porous 96% silica glass, and a photosensitive product thus produced, are described. The method includes introducing NaCl and KH.sub.2 PO.sub.4 into the pores using at least one liquid vehicle and at least partly removing the liquid vehicle from the pores. Thereafter, AgNO.sub.3 is introduced into the NaCl and KH.sub.2 PO.sub.4 -containing pores using an liquid vehicle before heating the porous glass support to remove remaining liquid vehicle and to react the NaCl, KH.sub.2 PO.sub.4, and AgNO.sub.3 to form a photosensitive silver and chlorine-containing polyphosphate material in situ in the pores of said support.

Abstract: A process for producing transparent high-annealing-point 96% silica glass comprising the steps of depositing a carbon film on the pore walls of the glass, heating the glass and film under non-oxidizing conditions, and removing the carbon film by oxidation, is described.

Abstract: A process for removing hydroxyl groups from porous 96% silica glass to provide dewatered porous or consolidated glass, which method comprises the step of contacting the porous glass with water vapor prior to heating in a dry environment, is described.

Abstract: The present invention relates to a method of producing a borosilicate glass exhibiting a low coefficient of thermal expansion, viz., less than about 20 .times. 10.sup..sup.-7 /.degree. C. over the range of room temperature to 300.degree. C., an ability to withstand repeated thermal cycling between room temperature and temperatures up to 1300.degree. C. and higher without devitrification, and the ability to flow, when present in particulate form, at temperatures between about 1000.degree.-1250.degree. C. The method contemplates impregnating a porous, essentially alkali metal-free, high silica material with a solution or a molten mass of a B.sub.2 O.sub.3 -containing compound, the B.sub.2 O.sub.3 -containing compound also being essentially free from alkali metals. The impregnated glass is thereafter dried to eliminate any solvent. High emissivity can be imparted by incorporating minor amounts of such materials as CoO, NiO, MoO.sub.3, Fe.sub.2 O.sub.3, and V.sub.2 O.sub.5 as dopants during the impregnation step.

Abstract: A method for providing broad-band antireflective surface layers on a chemically durable borosilicate glass which comprises phase-separating the glass by heat treatment at 630.degree.-660.degree. C., removing a siliceous surface layer from the glass, and treating the glass in an aqueous solution containing both H.sup.+ ions and F.sup.- ions for a time sufficient to produce the antireflective surface layer, is described. Antireflective surface layers exhibiting reflectances as low as 0.5% throughout the wavelength range from about 0.4-2.0 microns have been produced.

Abstract: The instant invention relates to the production of composite glass articles involving the bringing together of two or more glasses, while in the molten state, into an integral unit. More particularly, the present invention is concerned with the manufacture of such articles wherein a reaction occurs at the interface between the laminae of molten glass such that an opal phase is spontaneously produced in situ thereat.

Abstract: Ultra-low expansion ceramic articles, having average linear coefficients of thermal expansion below about 5.4 .times. 10.sup.-.sup.7 /.degree.C over the range from room temperature to 1000.degree.C, are produced by removal of MgO and Al.sub.2 O.sub.3 from cordierite articles by acid leaching to produce ceramic articles having oxide compositions in the range of about 55-75% SiO.sub.2, 18-32% Al.sub.2 O.sub.3, and 7-13% MgO which are characterized by the presence of a major amorphous silica-rich phase.

Abstract: An improved process for the production of carbon-containing glass resistors comprising impregnating porous glass with a furfuryl alcohol solution, polymerizing the furfuryl alcohol retained in the glass by contacting the glass with hydrochloric acid to produce a resin, drying the glass to remove moisture therefrom, and firing the glass in a non-oxidizing atmosphere to convert the resin to carbon, is described. Substantially improved yields of high value resistors are obtained by the process.

Abstract: An improved process for the production of carbon-containing glass resistors comprising impregnating porous glass with a furfuryl alcohol solution, flash-heating the impregnated glass at temperatures in the range of 150.degree.-225.degree.C. to polymerize the alcohol to a resin, and firing in a non-oxidizing atmosphere to convert the resin to carbon, is described. Substantially improved yields of high value resistors are obtained by the process.