Abstract: This invention is concerned with the preparation of glasses exhibiting transition temperatures below 450.degree. C., working temperatures below 500.degree. C., and exceptional resistance to mild aqueous alkaline solutions consisting essentially, expressed in terms of mold percent on the oxide basis, of:______________________________________ ZnO 12-55 K.sub.2 O 0-25 P.sub.2 O.sub.5 28-40 Li.sub.2 O + Na.sub.2 O + K.sub.2 O 10-35 Li.sub.2 O 0-25 Rare earth metal oxide 1-5 Na.sub.2 O 0-25 ______________________________________At least two alkali metal oxides will most desirably be present.

Abstract: The invention relates to the moulding of glass articles.It concerns an automatic machine for moulding glass articles by means of pressing, comprising a single split mould (1), means for opening and closing the mould, means (9, 10) for introducing a metered batch of molten glass into the said mould, pressing means (12) in order to shape the batch of molten glass introduced into the said mould, and means for taking away the shaped glass article, characterized in that the mould has means (16) for periodically cooling using a pulse of cooling fluid, and in that it additionally comprises a plurality of mould bases (13) capable of being brought successively into a position in which they complete the said mould, the said mould bases additionally serving to take away the still malleable glass article having just been moulded.

Abstract: Photosensitively opacifiable glasses requiring very short exposures to ultraviolet radiation to effect the development of opacity are processed by heating to nucleate Ag followed by cooling to nucleate NaF on the Ag followed by heating to grow the NaF. The glasses contain, expressed in terms of weight percent on the oxide basis, about 14-18% Na.sub.2 O, 0-6% ZnO, 6-12% Al.sub.2 O.sub.3, 0-5% B.sub.2 O.sub.3, 65-72% SiO.sub.2, and 0-0.2% Sb.sub.2 O.sub.3, and 0.007-0.04% Ag, 0.008-0.05% CeO.sub.2, 0.7-1.25% Br, and 1.5-2.5% F as analyzed in the glass, the sum of those components are at least 90% of the total composition.

Abstract: This invention is directed to a method for making tinted photochromic glass articles having an integral reduced surface layer exhibiting color, the glass utilizing silver halide crystals as the photochromic agent. The method generally comprises heat treating the glass article in a heating chamber in an atmosphere of flowing hydrogen at temperatures below 500.degree. C.

Abstract: This invention relates to photochromic glasses exhibiting refractive indices greater than 1.59, densities no higher than 3.1 g/cm.sup.3, Abbe numbers of at least 40, weight losses no greater than 0.01 mg/cm.sup.2 in the A.O. test, and which, when exposed to actinic radiation at room temperatures, darken to transmittances below 40% and fade at least 15 percentage points of transmittance after five minutes' removal from the actinic radiation.

Abstract: This invention relates to the production of ceramic materials which exhibit a dielectric constant in excess of 105, when measured at room temperature, and a small temperature coefficient of capacitance across the temperature range of -55.degree. to 125.degree. C., when compared to the capacitance measured at room temperature, which material has a composition encompassed within one of the following general formulae:(Bi.sub.2 O.sub.2).sup.2+ (A.sub.m-1 B.sub.m O.sub.3m+1).sup.2- ; (I)(Bi.sub.2 O.sub.2).sup.2+ (A.sub.m-1 B.sub.m Zr.sub..beta. O.sub.3m+.delta.+1).sup.2- ; and (II)(Bi.sub.2 O.sub.2).sup.2+ (A.sub.m-1 B.sub.m Mn.sub..gamma. O.sub.3m+.delta.+1).sup.2- (III)(Bi.sub.2 O.sub.2).sup.2+ (A.sub.m-1 B.sub.m Zr.sub..beta. Mn.sub..gamma. O.sub.3m+.delta.+1).sup.

Abstract: This invention provides a method for forming ring laser gyroscope frames without extensive machining. Parts of necessary configurations for such frames are so fashioned that they can be sealed together into a unit. Those parts are prepared from very low expansion glass-ceramics of particular compositions and are sealed together with low expansion, thermally devitrifiable sealing glasses, also of particular compositions.

Abstract: This invention relates to coatings for application to glass lenses to provide a tint thereto. The coatings at a thickness of no more than 10 microns in conjunction with organic dyes conventionally used to tint organic plastic lenses will impart a visible transmission of less than 50%, preferably less than 30%. The coatings consist essentially of an alkyl siloxane containing a dipolar silane selected from the group consisting of an ester-functional silane, a hydroxy-functional silane, amino-functional silane, a carboxylic acid-functional silane, and a halide form of those silanes.

Abstract: This invention is directed to the production of laminated, transparent, polarizing glass articles. The inventive method contemplates five basic steps:(1) forming parallel microgrooves on a surface of a glass support;(2) washing and drying said surface;(3) depositing on said surface a mixture of organic colorants corresponding to the three primary colors and exhibiting a nematic state to yield a coating displaying polarizing properties;(4) treating the polarizing coating with an aqueous solution of inorganic salts having an acid pH; and(5) applying a continuous, optically transparent, composite film upon the polarizing coating and bonding it thereto.

Abstract: This invention relates to the production of opaque, beige-tinted glass-ceramic articles consisting essentially, in weight percent, of______________________________________ SiO.sub.2 66-70 TiO.sub.2 3.5-5.5 Al.sub.2 O.sub.3 16.5-19.5 CeO.sub.2 1.5-2.75 Li.sub.2 O 2-4 As.sub.2 O.sub.3 0-1.5 MgO 1-5 F 0-1.2 ZnO 0.5-2 ZrO.sub.2 0-2.5 Na.sub.

Abstract: The present invention is related to the fabrication of a magnetic memory storage device consisting essentially of a head pad and a rigid information disk, which disk consists essentially of a rigid substrate having a coating of magnetic media on the surface thereof facing the head pad. More particularly, this invention is directed to a substrate for use in the disk. The substrate is selected from two different groups of glass-ceramics: the first group contains a sheet silicate as the predominant crystal phase; and the second group contains a chain silicate as the predominant crystal phase.

Abstract: The present invention is directed to a four-step process for molding glass articles of high precision and excellent surface figure. A glass preform having an overall geometry closely approximating that of the desired final product is placed into a mold, the mold and preform are brought to a temperature at which the glass exhibits a viscosity between 10.sup.8 -10.sup.12 poises, a load is applied to shape the glass into conformity with the mold, and thereafter the resulting glass article is removed from the mold at a temperature above the transformation range of the glass. The glass article is then annealed.

Abstract: The present invention is directed to a method for synthesizing fluorine-containing, aluminosilicate crystals having a stoichiometry approximating that of topaz. The method comprises three basic steps:(1) vapors of a readily-oxidizable compound of silicon and of a readily-oxidizable compound of aluminum and fluorine are passed to a flame oxidation burner;(2) amorphous fluorine-containing, aluminosilicate particles resulting from the combustion of those gases are collected; and(3) the collected particles are sintered into an integral body at a temperature between about 650.degree.-925.degree. C.

Abstract: This invention is directed to the preparation of glasses exhibiting a transition temperature below 450.degree. C., a working temperature below 500.degree. C., and excellent resistance to attack by water and mild aqueous alkaline solutions. The glasses consist essentially, in mole percent, of at least 65% total of 23-55% ZnO, 28-40% P.sub.2 O.sub.5, and 10-35% R.sub.2 O, wherein R.sub.2 O consists of at least two alkali metal oxides in the indicated proportions selected from the group consisting of 0-25% Li.sub.2 O, 0-25% Na.sub.2 O, and 0-25% K.sub.2 O, and up to 35% total of optional ingredients in the indicated proportions selected from the group consisting of 0-6% Al.sub.2 O.sub.3, 0-8% B.sub.2 O.sub.3, 0-8% Al.sub.2 O.sub.3 +B.sub.2 O.sub.3, 0-15% Cu.sub.2 O, 0-5% F, 0-35% PbO, 0-35% SnO, 0-35% PbO+SnO, 0-5% ZrO.sub.2, 0-4% SiO.sub.2, and 0-15% MgO+CaO+SrO+BaO+MnO, consisting of 0-10% MgO, 0-10% CaO, 0-10% SrO, 0-12% BaO, and 0- 10% MnO.

Abstract: This invention relates to glasses consisting essentially, by weight, of about 35-72% Ln.sub.2 O.sub.3, 5-37% Al.sub.2 O.sub.3, 29-56% SiO.sub.2, and 4-7.5% N. Up to about one-half of the Ln.sub.2 O.sub.3 on an atomic basis may be replaced with SrO and/or BaO. A transparent glass can be formed which contains about 40-60% on a molar basis of Ln.sub.2 O.sub.3 +SrO and/or BaO and wherein the atomic ratio Sr and/or Ba:Sr and/or Ba+Ln >0.4.

Abstract: The present invention is directed to transparent, essentially haze-free glass-ceramic articles exhibiting moduli of rupture in excess of 10,000 psi which consist essentially, in weight percent, of 3-6% Li.sub.2 O, 17-23% Al.sub.2 O.sub.3, 1-4% B.sub.2 O.sub.3, 60-70% SiO.sub.2, 3-6% TiO.sub.2 and/or ZrO.sub.2, 25-500 ppm Cr.sub.2 O.sub.3, and 1-5 mole percent of a glass modifying oxide selected from the group consisting of 0-3% K.sub.2 O and 0-2.5% SrO and/or BaO.

Abstract: This invention relates to glass, glass-ceramic, and/or ceramic vessels which are coated with an organic polymer to reduce breakage and to protect the user from flying fragments when the vessels are broken upon impact. The invention contemplates strongly bonding the organic polymer in a small area around the mouth of the vessel only.

Abstract: This invention is primarily directed to the production of transformation toughened ZrO.sub.2 -containing ceramic alloys wherein the toughening agent is selected from the group consisting of a rare earth metal vanadate and a magnesium and/or calcium tungstate/molybdate, and SnO.sub.2 can be utilized as a toughening agent and/or a stabilizing agent for ZrO.sub.2.

Abstract: Ultraviolet transmitting glasses exhibiting coefficients of thermal expansion between 46-52.times.10.sup.-7 /.degree.C. and transmittances at a thickness of 1 mm of at least 80% at a wavelength of 254 nm which are essentially free of fluoride and consist essentially, in mole percent, of 60-70% SiO.sub.2, 16-20% B.sub.2 O.sub.3, 1-8% Al.sub.2 O.sub.3, 1-6% Li.sub.2 O, 2.5-5% N.sub.2 O, 0-3% K.sub.2 O, and 0-1.25% Cl, w9herein the mole ratio R.sub.2 O:R.sub.2 O.sub.3 is greater than 0.3, but less than 0.5.

Abstract: There is disclosed a hybrid circuit embodying a crossover formed on a low expansion substrate of aluminum nitride, mullite or a cordierite-type glass-ceramic. The crossover is a thick film dielectric composed of a glass-ceramic having a primary crystal phase of willemite and a secondary phase of cordierite.