Abstract: A material system and method for imparting non-stick and non-wetting properties to an inorganic article having hydroxyl groups on its surface, the system comprising a silane having the formula R.sub.n SiX.sub.4-n, wherein n is 1-2 and X is a hydrolyzable group, a colloidal metal oxide sol, and an acidified aqueous mixture with a lower alkanol.

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: This invention is directed to photochromic glasses which darken to a brown coloration upon exposure to actinic radiation, which glasses have a refractive index of about 1.6, an Abbe number between 42-47, a density less than 2.82 g/cm.sup.3, and are preferably essentially free of TiO.sub.2. The glass compositions consist generally, in weight percent, of:______________________________________ SiO.sub.2 43-52 K.sub.2 O 2-9 Nb.sub.2 O.sub.5 6-16 B.sub.2 O.sub.3 12.5-18 MgO 0-5 Ag 0.100-0.175 Al.sub.2 O.sub.3 0-3 CaO 0-5 Cl 0.140-0.350 ZrO.sub.2 6-14 SrO 0-9 Br 0.093-0.195 Li.sub.2 O 1.5-3.5 BaO 0-9 CuO 0.008-0.030. Na.sub.

Abstract: A transparent photochromic glass displaying a pink hue in the darkened state which, in bodies of 2 mm cross section, will exhibit the following optical properties:(a) a clear (undarkened) luminous transmittance greater than 82%;(b) a darkened luminous transmittance after 15 minutes' exposure to actinic radiation at 25.degree. C. between about 20-32%;(c) a darkened luminous transmittance after 15 minutes' exposure to actinic radiation at 40.degree. C. between about 35-55%;(d) a rate of fading such that the luminous transmittance after 5 minutes' removal from actinic radiation at 25.degree. C. will be at least 30 percentage units higher and will exhibit a luminous transmittance greater than 50%;(e) a x trichromatic coordinate between 0.3500 and 0.3700; and(f) a y trichromatic coordinate between 0.3250 and 0.3450;said glass consisting essentially, expressed in terms of weight percent on the oxide basis, of______________________________________ SiO.sub.2 52-58 ZrO.sub.2 1.5-2.8 K.sub.2 O 4-8 B.sub.2 O.sub.

Abstract: A process to synthetize zircon as an ultra thin coating and comprising: (A) mixing an alcoholic sol resulting from hydrolysis of a silicon alkoxide with an alcoholic solution of a chelated zirconium compound and in the presence of and with a doping agent, until a homogenous mixed sol is obtained; (B) forming a matured sol containing colloidal particles and/or the polymeric entities from the mixed sol; (C) forming a coating of the matured sol on a microporous substrate; (D) drying slowly the sol coating into a gel coating free of flaws; and (E) firing the gel coating at a temperature of 900.degree. to 1500.degree. C. to form an ultra thin zircon layer. Use of the zircon layer obtained above as an ultrafiltration membrane or as a protective coating.

Abstract: This invention relates to glasses exhibiting refractive indices higher than 1.880, Abbe numbers of at least 29, densities lower than 4.1, good chemical durability and stability against devitrification, and an integrated transmission over the range of 380-800 nm at a thickness of 10 mm greater than 79%, the glasses consisting essentially, expressed in terms of weight percent on the oxide basis, of______________________________________ SiO.sub.2 5-8 B.sub.2 O.sub.3 15-21 ZrO.sub.2 3-10 TiO.sub.2 7-17 Nb.sub.2 O.sub.5 20.5-26 ZrO.sub.2 + TiO.sub.2 + Nb.sub.2 O.sub.5 29-45 La.sub.2 O.sub.3 19-32 Y.sub.2 O.sub.3 0-9 CaO 8-16 SrO 0-5 BaO 0-5 MgO 0-5 CaO + SrO + BaO + MgO 8-16 ZnO 0-5 Li.sub.2 O 0-2 Na.sub.2 O 0-2 K.sub.2 O 0-2 Li.sub.2 O + Na.sub.2 O + K.sub.2 O 0-2.

Abstract: Thermally induced color is developed in a glass article containing a silver halide crystal phase by including in the glass batch a thermal reducing agent, retaining the thermal reducing agent in its lower valence state while meltinq the batch and forming the glass article and subsequently heat treating the article to partially reduce the silver halide crystal phase.

Abstract: This invention relates to the production of glasses exhibiting a refractive index between about 1.66-1.81, a softening point between about 625.degree.-675.degree. C., a strain point between about 455.degree.-490.degree. C., a linear coefficeint of thermal expansion (25.degree.-300.degree. C.) between about 53-65.times.10.sup.-7 /.degree.C., and good chemical durability which consist essentially, in weight percent, of:______________________________________ SiO.sub.2 24-42 Li.sub.2 O 0.2 Li.sub.2 O + Na.sub.2 O + K.sub.2 O 0-3.5 Al.sub.2 O.sub.3 3-7.5 Na.sub.2 O 0-2 ZrO.sub.2 0-2.5 B.sub.2 O.sub.3 2-7.5 K.sub.2 O 0-3 TiO.sub.2 0-8 PbO 35-57 La.sub.2 O.sub.3 0-8 La.sub.2 O.sub.3 + ZrO.sub.2 4-12.sub.

Abstract: This invention is directed to the preparation of silver halide-containing photochromic glasses exhibiting refractive indices between 1.585-1.610, Abbe numbers higher than 41, and densities less than 2.80 g/cm.sup.3 generally consisting essentially, in weight percent, of:______________________________________ SiO.sub.2 43-52 SrO 0.8-9 B.sub.2 O.sub.3 12.5-18 BaO 1-9 Al.sub.2 O.sub.3 0-3 K.sub.2 O 2-9 ZrO.sub.2 3-8 TiO.sub.2 2-8 Li.sub.2 O 1.5-3.5 Ag 0.100-0.175 Na.sub.2 O 0.3-3 Cl 0.140-0.350 Nb.sub.2 O.sub.5 4-9 Br 0.093-0.180 MgO 0-5 CuO 0.0080-0.

Abstract: The present invention is related to transparent, fast darkening and fading photochromic glasses.The glasses contain SiO.sub.2, B.sub.2 O.sub.3, Al.sub.2 O.sub.3, ZrO.sub.2, Li.sub.2 O, Na.sub.2 O, K.sub.2 O, MgO, CaO, SrO, BaO, ZnO, La.sub.2 O.sub.3, Nb.sub.2 O.sub.5, TiO.sub.2 as base glass components, Ag, Br, Cl, CuO as photochromic elements, with, optionally, Sb.sub.2 O.sub.3, As.sub.2 O.sub.3, and SnO.sub.2 as colorants to impart a brown color at darkening.The glasses have a refractive index greater than 1.585, an Abbe number greater than 42, and a density lower than about 2.80 g/cm.sup.3.

Abstract: This invention relates to the production of lightly tinted, photochromic glasses having base compositions consisting essentially, in weight percent, of______________________________________ SiO.sub.2 46-60 SrO 0-6 B.sub.2 O.sub.3 16-28 BaO 0-6 Al.sub.2 O.sub.3 4-11 P.sub.2 O.sub.5 0-5 ZrO.sub.2 2-6 TiO.sub.2 0-3 Li.sub.2 O 1.5-5 Ag 0.08-0.18 Na.sub.2 O 0-6 Cl 0.06-0.26 K.sub.2 O 2.5-9 Br 0.08-0.18 MgO 0-3.5 CuO 0.0001-0.0020 CaO 0-6 ______________________________________Glass color can be adjusted by introducing in excess of the above base composition, at least one of the following colorants in the indicated proportions of ______________________________________ Pd 0.00003-0.00015 Er.sub.2 O.sub.3 0.2-1.3 SnO.sub.2 0.05-0.3 Nd.sub.2 O.sub.3 0-0.7 Fe.sub.2 O.sub.3 0.05-0.15 Co.sub.3 O.sub.4 0-0.0080 NiO 0.005-0.

Abstract: This invention is directed to transparent photochromic glasses that can darken to a comfort range, i.e., between about 35-60%, or to a dark range, i.e., below 35%, depending upon glass composition, and will exhibit a faded transmittance after five minutes' removal from actinic radiation higher than 70%. The base compositions of the glasses consist essentially, in weight percent, of about______________________________________ SiO.sub.2 46-60 MgO 0-3.5 B.sub.2 O.sub.3 16-28 CaO 0-6 Al.sub.2 O.sub.3 4-11 SrO 0-6 ZrO.sub.2 2-6 BaO 0-6 Al.sub.2 O.sub.3 + ZrO.sub.2 6-13 MgO + CaO + SrO + BaO 0-7 Li.sub.2 O 2-5 P.sub.2 O.sub.5 0-5 Na.sub.2 O 0-4 TiO.sub.2 0-3 K.sub.2 O 2.5-9 ______________________________________For a comfort glass the photochromic elements consist essentially, as analyzed, of ______________________________________ Ag 0.13-0.18 Br 0.08-0.14 Cl 0.16-0.34 CuO 0.001-0.

Abstract: This invention is concerned with a glass for optical and/or ophthalmic applications having an index of refraction between about 1.78-1.82, an Abbe number greater or equal to 31, and a density less than about 3.80 g/cm.sup.3 consisting essentially, expressed in terms of weight percent on the oxide basis, of:______________________________________ SiO.sub.2 15-30 CaO 15-28 B.sub.2 O.sub.3 2-17 SrO 0-11 SiO.sub.2 + B.sub.2 O.sub.3 24-36 BaO 0-11 Al.sub.2 O.sub.3 0-6.5 MgO + CaO + 16-33 SrO + BaO Li.sub.2 O 0-5 ZnO 0-11 Na.sub.2 O 0-5 La.sub.2 O.sub.3 16-30 K.sub.2 O 0-5 ZrO.sub.2 0-10 Li.sub.2 O + Na.sub.2 O + K.sub.2 O 0-6 Nb.sub.2 O.sub.5 5-26 MgO 0-6 TiO.sub.2 0-14.

Abstract: This invention relates to glasses especially suitable for optical and ophthalmic applications which exhibit densities less than about 2.65 g/cm.sup.3, refractive indices between about 1.595-1.607, and Abbe numbers between about 40-47, and which consist essentially, in weight percent on the oxide basis, of______________________________________ SiO.sub.2 45-55 MgO and/or BaO and/or B.sub.2 O.sub.3 5-13 SrO and/or La.sub.2 O.sub.3 0-6 Al.sub.2 O.sub.3 0-5 CaO 0-12 Li.sub.2 O 1-7.5 ZnO 0-8 Na.sub.2 O 1-9 ZrO.sub.2 0-7 K.sub.2 O >10-24 TiO.sub.2 9.5-17.5 As.sub.2 O.sub.3 and/or Sb.sub.2 O.sub.3 0-1 and 13.5 < TiO.sub.2 + ZrO.sub.2 + La.sub.2 O.sub.3 + MgO <23.

Abstract: The invention relates to a process for the preparation of monolithic silica aerogels by drying silica gels under hypercritical conditions, which is characterized by the absence of washing of the silica gel, a high heating rate in the autoclave and purging of the autoclave after substantial removal of the solvent. Other preferred conditions are the use of an amount of water not exceeding 1.5 times the stoichiometric amount for the hydrolysis, hypercritical conditions corresponding to a temperature of 265.degree.-275.degree. C. and to a pressure of 150-200 bars, and so on. Use of the aerogels for the preparation of silica glass bodies or articles and of heat-insulating materials.