Abstract: This invention is directed to the production of spontaneous essentially non-crystalline opal glasses exhibiting a very dense, milky-white appearance and excellent resistance to weathering and attack by alkaline detergents consisting essentially, expressed in weight percent on the on the basis, of 1.9-3.6% K.sub.2 O, 4.2-7.3% Na.sub.2 O, 0.2-3% Li.sub.2 O, 0-1.2% MgO, 0-4.9% CaO, 0-12.5% BaO, 0-0.1% NiO, 0.4-4% ZnO, 5.3-9.6% B.sub.2 O.sub.3, 8.8-13.5% Al.sub.2 O.sub.3, 57.2-64.4% SiO.sub.2, and 1.0-2.2% F., where the sum of (MgO+CaO+BaO) is preferably in the range of 4.5-12.5%.

Abstract: The present invention is directed to glasses exhibiting annealing points between 682.degree.-702.degree. C., linear coefficients of thermal expansion (25.degree.-300.degree. C.) between 57-59.times.10.sup.-7 /.degree. C., and excellent resistance to attack by HCl and Na.sub.2 CO.sub.3 consisting essentially, in weight percent, of______________________________________ SiO.sub.2 56-60 Na.sub.2 O 0-3 Al.sub.2 O.sub.3 12-15 K.sub.2 O 0-3 B.sub.2 O.sub.3 5.5-7 Na.sub.2 O + K.sub.2 O 0.5-3. CaO 19-24.

Abstract: This invention is directed to the production of essentially defect-free high purity fused silica glass articles, the method comprising the following steps: (a) forming a green body from silica particulates or a porous body of amorphous silica; (b) sintering said body in a chamber by raising the temperature of the chamber to above 1720.degree. C., while purging the chamber with helium or applying a vacuum to the chamber; and (c) consolidating the sintered body in a chamber by raising the temperature within the chamber to at least 1750.degree. C., introducing an inert gas into the chamber at a pressure less than about 6.9 MPa (1000 psig), and cooling the chamber while maintaining the pressurized atmosphere to a temperature at least below the annealing point of the glass. In the most preferred practice, a green body of silica particulates will be prepared via a sol-gel process.

Abstract: A non-photochromic colored glass containing crystals of precipitated cuprous oxide in a matrix of glass, the matrix glass consisting essentially of, in cation percent, 35-75% SiO.sub.2, 15-45% B.sub.2 O.sub.3, 0-12% Al.sub.2 O.sub.3, the Al.sub.2 O.sub.3 being less than 10% when the SiO.sub.2 is over 55%, 0-5% ZrO.sub.2, 0-12% Li.sub.2 O, 0-20% Na.sub.2 O, 0-12% K.sub.2 O, the sum Li.sub.2 O+Na.sub.2 O+K.sub.2 O being 5-20%, 0-5% CaO+BaO+SrO, 0.4-1.75% Cu.sub.2 O, 0-2% As.sub.2 O.sub.3, 0-2% Sb.sub.2 O.sub.3, 0-1% SnO.sub.2, the sum As.sub.2 O.sub.3 +Sb.sub.2 O.sub.3 +SnO.sub.2 being 0.5-2%, characterized by 0.075.ltoreq.R-value .ltoreq.0.

Abstract: Cuprous halide- or a cuprous-cadmium halide-containing glass articles are produced which are essentially completely opaque to ultraviolet radiation and can De essentially completely opaque to radiation within the region of wavelengths of up to 550 nm, but are transparent to visible radiations having a wavelength longer than the radiation within the region of opacity. The method involves exposing the glass articles to a hydrogen gas-containing atmosphere at a temperature between about 375.degree.-500.degree. C. for a period of at least 18 hours to develop an integral reduced layer in at least one surface of the article having a depth effective to prevent the transmission of ultraviolet radiation and radiation having a wavelength up to 550 nm through the article.

Abstract: This invention is directed to the production of thermally crystallizable glasses which, upon heat treatment in contact with alumina particulates, will form a strong glass-ceramic-bonded composite body, the excellent bonding being attributed to the presence of lithium aluminoborate crystals. The glass-ceramic composition consists essentially, in weight percent, of______________________________________ SiO.sub.2 25-55 MgO 0-12 B.sub.2 O.sub.3 35-65 Li.sub.2 O + MgO 4-16. Li.sub.

Abstract: Glass articles transparent to visible radiation, but opaque to ultraviolet radiation, rendering them particularly suitable for protecting the wearer of such lenses from exposure to laser radiation in the ultraviolet regions of the electromagnetic spectrum are produced. The method involves exposing silver halide-containing glass articles to flowing hydrogen in a heat chamber operating at 375.degree.-500.degree. C. for at least four hours to produce an integral reduced layer in at least one surface of the articles of sufficient depth to prevent the transmission of ultraviolet radiation through the articles.

Abstract: This invention is directed to the production of glasses essentially free of Nb.sub.2 O.sub.5, and having refractive index close to 1.7, an Abbe number of about 35 and a density close to 3.2. The glasses consist essentially in weight percent on the oxide basis, of______________________________________ SiO.sub.2 38-45 TiO.sub.2 15-<20 ZrO.sub.2 6-10 La.sub.2 O.sub.3 0.5-4 BaO 12-19 CaO 3-8 BaO + CaO + SrO 17-25 Na.sub.2 O 2-6 K.sub.2 O 4-8 Li.sub.2 O + Na.sub.2 O + K.sub.2 O 6-10.

Abstract: This invention is directed to the production of glasses useful for ophthalmic applications which exhibit excellent resistance to the development of coloration upon being exposed to x-radiation and excellent resistance to the development of solarization. The glass compositions are essentially free of lead and consist essentially, in weight percent, of______________________________________ SiO.sub.2 60-70 ZrO.sub.2 0.5-2 TiO.sub.2 0-1.5 B.sub.2 O.sub.3 0.5-5 CeO.sub.2 0.1-0.3 Sb.sub.2 O.sub.3 0-0.5 Al.sub.2 O.sub.3 2-6 Li.sub.2 O 0-2 SO.sub.3 0-0.3 Na.sub.2 O 9-14 MgO 0-5 Br 0-0.5 K.sub.2 O 3-10 SrO 0-5 Cl 0-0.5 CaO 0.5-4 BaO 0-5 F 0-0.5.

Abstract: The present invention is directed to the preparation of frit pastes suitable for sealing together preformed glass parts, being especially suitable for sealing glass panels to funnels of cathode ray tubes. The pastes comprise a mixture of frit particles, a lacquer, and at least one additive in an amount of 0.0005-2% by weight total of the lacquer. The preferred additives are selected from the group of alkyl organic phosphate esters, a mixed titanium ortho ester complexes, and substituted sorbitols in the polyol acetal family.

Abstract: An apparatus for reducing the amount of electrical power needed to attain light-off of a catalytic converter, particularly a catalytic converter for internal combustion engines. In addition to a resistance-heated catalytic converter, means are provided for varying the air/fuel ratio in the exhaust gas system for the purpose of reducing the ignition temperature of the exhaust gas stream, thereby further reducing the electrical energy required to attain light-off during cold-start.

Abstract: The invention relates to the use of aqueous emulsions of silicone resins in forming cellular zeolite substrates which can be dried rapidly without incurring blistering while still exhibiting good strength and zeolite activity.

Abstract: The instant invention describes a method for preparing a stable, anhydrous non-hygroscopic zinc phosphate compound which is suitable for use as a batch material in the preparation of zinc-phosphate glasses. This method comprises three basic steps: first, forming an aqueous slurry mixture by intimately mixing a mixture containing phosphoric acid and a zinc-containing compound whereby the so-formed slurry mixture is comprised of a mixture of zinc hydrogen phosphates and exhibits a P.sub.2 O.sub.5 /ZnO weight ratio range between about 1.2 to 2.0; second, heating the so-formed slurry mixture to a temperature and for a time sufficient to achieve both a removal of a sufficient amount of water and the phase transformation of the zinc hydrogen phosphates resulting in zinc-phosphate material comprised of granular solid mixture of zinc metaphosphates and zinc pyrophosphate and third, cooling the zinc-phosphate material to room temperature.

Abstract: This invention is directed at glass-ceramic articles, and methods for producing such articles, exhibiting Young's modulus between about 14 to 24.times.10.sup.6 psi and a fracture toughness in excess of 1.0 MPa.sqroot. in. The crystal phase assemblage is comprised predominately of generally uniformly-sized spinel-type crystals which are uniformly dispersed within a highly siliceous residual glass matrix phase. The composition of these glass-ceramic articles is consists essentially, expressed in terms of weight percent on the oxide basis, of 35-60% SiO.sub.2, 20-35% Al.sub.2 O.sub.3, 0-25% MgO, 0-25% ZnO, at least about 10% MgO+ZnO, 0-20% TiO.sub.2, 0-10% ZrO.sub.2, 0-2% Li.sub.2 O and 0-8% NiO. However, if the Al.sub.2 O.sub.3 constituent is present in an amount less than about 25%, the TiO.sub.2 +ZrO.sub.2 +NiO amount should be at least 5%. The composition may also contain up to 5% of optional constituents selected from the group consisting of BaO, CaO, PbO, SrO, P.sub.2 O.sub.5, B.sub.2 O.sub.3, Ga.sub.2 O.

Abstract: This invention is directed to glass compositions particularly designed for use in rear projection tube applications. The glass compositions are essentially free from ZnO, PbO and other easily reducible metal oxides other than Sb.sub.2 O.sub.3 and are essentially colorless. The glasses exhibit essentially no browning discoloration upon being exposed to high voltage electrons, linear coefficients of thermal expansion (25.degree.-300.degree. C.) between about 97-100.times.10.sup.-7 .degree. C., annealing points not lower than about 475.degree. C., strain points not lower than about 440.degree. C., electrical resistivities expressed as Log R greater than 9 at 250.degree. C. and greater than 7 at 350.degree. C., and liquidus temperatures below about 1100.degree. C. The glass compositions consist essentially, expressed in terms of weight percent on the oxide basis, of______________________________________ SiO.sub.2 55-60 K.sub.2 O 5.75-10 Al.sub.2 O.sub.3 1-3 Na.sub.2 O + K.sub.2 O 10.5-14 ZrO.sub.2 0-3.5 K.sub.

Abstract: The present invention relates to the production of lead-free glasses exhibiting densities of at least 2.9 g/cm.sup.3 and refractive indices of at least 1.545 which consist essentially, in weight percent, of______________________________________ SiO.sub.2 51-63 Al.sub.2 O.sub.3 0-5 Li.sub.2 O 0-3 ZrO.sub.2 0-6 Na.sub.2 O 0-8 SiO.sub.2 + Al.sub.2 O.sub.3 + 55-66 ZrO.sub.2 K.sub.2 O 0-12 TiO.sub.2 0-3 Li.sub.2 O + Na.sub.2 O + 7-15 CaO 0-5 K.sub.2 O SrO 0-<8 MgO 0-3 BaO >13-21 B.sub.2 O.sub.3 0-3 ZnO 5-15 La.sub.2 O.sub.3 0-8.

Abstract: A method of forming complex shapes from soft solvent-containing batches and maintaining the integrity of such formed bodies. The formed bodies are made self-supporting immediately after forming or soon thereafter by contacting the shaped body with a drying or hardening liquid in which the solvent is soluble. A method is also disclosed for simultaneously drying a formed body and creating or increasing the porosity of the body by adding solid particles which are soluble in the drying liquid.

Abstract: This invention is directed to the production of a transparent glass which, in a thickness of 4 mm, exhibits a champagne color as defined by chromaticity coordinates (Illuminant C) within the ranges______________________________________ x 0.3166-0.3281 y 0.3211-0.3305 Y 77-88, ______________________________________said glass consisting essentially, by weight, of 0.05-0.25% iron oxide, expressed in terms of Fe.sub.2 O.sub.3, >25-175 ppm nickel oxide, expressed in terms of NiO, and >10-100 ppm Se in a soda lime silicate base composition.

Abstract: This invention relates to a method for controlling the conductance of heated structures used to initiate faster light-off in emission control systems such as used for automotive catalytic converters, diesel particulate filters and industrial stacks and other applications in which the exhaust gas stream temperature is too low to initiate fast light-off. The invention also relates to a method for minimizing the amount of conductive material used for making such structures.

Abstract: The present invention features a process and apparatus for drying ceramic structures in an electromagnetic energy field. The apparatus comprises a cradle or setter for supporting the ceramic structure which is made of a light-weight, tough, temperature-resistant material which does not absorb energy in the radio frequency range, for example, fiberglass reinforced polyester. The setter is also characterized by many apertures to allow passage of air or moisture, and is designed to avoid trapped air volumes.