Abstract: The present invention is concerned with the production of spontaneous opal glasses which, after thermal tempering, demonstrate a dense coloration ranging from ivory through yellow-beige to tan to a grayish-brown appearance, consisting essentially, by weight on the oxide basis, of 8-9% Na.sub.2 O, 2-2.5% K.sub.2 O, 5-6.5% CaO, 8-10% ZnO, 1-2% B.sub.2 O.sub.3, 10-11% Al.sub.2 O.sub.3, 3-4% F, 0.005-0.1% NiO, 0-2% CeO.sub.2, 0-4%TiO.sub.2, 0.5-6% CeO.sub.2 +TiO.sub.2, 0-0.5% As.sub.2 O.sub.3, and 57-61% SiO.sub.2.

Abstract: This invention is directed to the production of sealing glasses capable of forming strong, non-porous seals with glasses containing at least 10% by weight of an alkali metal oxide such as are used in the fabrication of the glass membranes utilized in sodium-sulfur and potassium-sulfur batteries. The inventive seals require an interdiffusion of ions to occur between the sealing glass and the glass being sealed. Glasses presently employed as membrane glasses for such batteries have base compositions within the Na.sub.2 O-B.sub.2 O.sub.3 and K.sub.2 O-B.sub.2 O.sub.3 systems. The inventive sealing glasses consist essentially, expressed in mole percent on the oxide basis, of about 3-30% R.sub.2 O and 60-95% B.sub.2 O.sub.3, wherein R.sub.2 O consists of K.sub.2 O, Rb.sub.2 O, Cs.sub.2 O, and mixtures thereof and, optionally, Al.sub.2 O.sub.3 is substituted for up to one-half the B.sub.2 O.sub.3 content on a molar basis.

Abstract: The present invention is concerned with glass-ceramic articles which are extremely resistant to impact and spontaneous delayed breakage, are capable of being sawn with a diamond wheel to a depth of over one-third the cross section thereof without breakage, and exhibit modulus of rupture values of at least 150,000 psi. The articles consist of a body portion and an integral surface compression layer having a depth of at least 0.005". The body portion consists essentially, in weight percent, of about 8-13% Na.sub.2 O, 7-13% K.sub.2 O, 30-36% Al.sub.2 O.sub.3, 35-43% SiO.sub.2, and 6-10% RO.sub.2, wherein RO.sub.2 consists of 6-10% TiO.sub.2 and 0-4% ZrO.sub.2, wherein the molar ratio Al.sub.2 O.sub.3 :SiO.sub.2 is >0.5 but <0.6 and the molar ratio K.sub.2 O:Na.sub.2 O is >1:3 but <1 and contains nepheline solid solution crystals corresponding to the formula Na.sub.8-x K.sub.x Al.sub.8 Si.sub.8 O.sub.32, with x varying from 0.25-4.73, as the predominant crystal phase.

Abstract: A polychromatic glass article, colored by silver, is disclosed wherein the silver occurs as an anisotropic film at the surface of lithium bromide spherulites which crystallize directly on silver nuclei from lithium silicate and lithium aluminosilicate glasses. The article is produced by sequential radiation exposures and heat treatments of the glass.

Abstract: This invention relates to the manufacture of spontaneous opal glasses demonstrating a dense, milky-white appearance, excellent resistance to attack by water and detergents, softening points in excess of 760.degree. C., and containing either NaBaPO.sub.4 or Na.sub.5 P.sub.3 O.sub.10 as the predominant crystal phase. The glasses consist essentially, expressed in weight percent on the oxide basis, of 6-12% Na.sub.2 O, 5-16% BaO, 0.9-7% Al.sub.2 O.sub.3, 2-7% B.sub.2 O.sub.3, 55-70% SiO.sub.2, and 5-9% P.sub.2 O.sub.5.

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 oxide basis, of 2-5% K.sub.2 O, 4-10% Na.sub.2 O, 4.5-12% RO, wherein RO consists of 0-3% MgO, 0-6% CaO, 0-8% SrO, and 0-11% BaO, 4-9% B.sub.2 O.sub.3, 6-15% Al.sub.2 O.sub.3, 0-5% TiO.sub.2, 51-66% SiO.sub.2, 1-6% P.sub.2 O.sub.5, and 1-5% F.

Abstract: The instant invention is directed to the production of highly polarizing glasses, i.e., the glasses exhibit dichroic ratios up to 40 and higher, from silver-containing glasses that are characterized as being phase separable or, more preferably, as being photochromic because of the presence of silver halide particles therein, i.e., particles selected from the group of AgCl, AgBr, and AgI. The inventive method contemplates two general steps:(a) the glasses are elongated under stress such that the glass phases and/or silver halide particles are elongated and aligned in the direction of the stress; and(b) the elongated glasses are heat treated in a reducing environment at temperatures below the annealing point of the glass but above about 300.degree. C. to reduce a portion of the silver ions in the glass to metallic silver which is deposited in at least one of the glass phases and/or along the phase boundaries of the glass phases and/or deposited upon the silver halide particles.

Abstract: The instant invention is drawn to glass-ceramics especially designed for the fabrication of radomes, wherein cordierite is the predominant crystal phase but which also contain minor amounts of cristobalite, magnesium-aluminum titanate, and rutile, having overall compositions consisting essentially, expressed in weight percent on the oxide basis, of about______________________________________ MgO 15-18 Al.sub.2 O.sub.3 21-25 SiO.sub.2 48-53 TiO.sub.2 9.5-11.5 As.sub.2 O.sub.

Abstract: The instant invention is concerned with glass envelopes for tungsten-halogen lamps. The glasses exhibit a strain point higher than 750.degree. C., a coefficient of thermal expansion (0.degree.-300.degree. C.) between 42-44.times.10.sup.-7 /.degree.C., a liquidus temperature below 1300.degree. C., a viscosity at the liquidus of at least 40,000 poises, and consist essentially, in weight percent on the oxide basis, of 64-68% SiO.sub.2, 11-14% CaO, 16.5-18.5% Al.sub.2 O.sub.3, and 2-6.5% SrO+BaO consisting of 0-4% SrO and 0-5% BaO. The preferred glasses demonstrate a viscosity of less than 1000 poises at temperatures no higher than 1520.degree. C. and contain at least 3% total of SrO+BaO, those components being present in a molar ratio SrO:BaO ranging from 2:1-1:2.

Abstract: There is disclosed a method of producing an image of an original multi-color subject in polychromatic glass by employing, as a mask during initial exposure of the glass, a continuous tone, ultra-violet transmitting, film negative in which each color in the original subject is recorded in terms of a unique film density corresponding to that color in the glass and capable of conditioning the glass for development of such color by transmission of a single predetermined exposure flux. Methods of preparing the mask are also disclosed.

Abstract: The instant invention is directed to glasses manifesting solar transmissions (350-2100 nm) through a 2.54 mm thick sheet in excess of 90% which can be prepared from conventional glass batch materials containing up to 0.1% iron, expressed as Fe.sub.2 O.sub.3, as impurities. The inventive glasses consist essentially, expressed in weight percent on the oxide basis as calculated from the batch, of______________________________________ Al.sub.2 O.sub.3 7-13 B.sub.2 O.sub.3 7-10 Na.sub.2 O 6-11 K.sub.2 O 2-7 CaO 2-7 TiO.sub.2 0.1-1 As.sub.2 O.sub.3 0-1 Sb.sub.2 O.sub.3 0-1 SiO.sub.2 Balance ______________________________________Part of the batch materials is added in the form of nitrates in a sufficient amount to virtually completely oxidize all the tramp iron present to the Fe.sup.+3 state.

Abstract: This invention relates to the production of large shapes of metallic glasses from finely-dimensioned ribbons powders, flakes, wires, fibers, or filaments thereof. The inventive method contemplates placing the precursor finely-dimensioned articles of metallic glass into contact with one another and then hot pressing the mass at temperatures in the close vicinity of the glass transition temperature with applied forces of at least 1000 psi. One metallic glass, Fe.sub.58 Cr.sub.14 Cu.sub.6 Si.sub.6 B.sub.6, which is readily shaped into bulk bodies via the inventive method, exhibits excellent resistance to attack by sea water.

Abstract: This invention is directed to spontaneous opal glasses wherein Ba.sub.2 F(PO.sub.4) constitutes the predominant crystalline opal phase. The glasses exhibit softening points in excess of 710.degree. C., excellent chemical durability, and consist essentially, in weight percent on the oxide basis, of 6-10% Na.sub.2 O, 1-6% K.sub.2 O, 4-11% BaO, 9-18% Al.sub.2 O.sub.3, 50-70% SiO.sub.2, 3.5-7% P.sub.2 O.sub.5, and 1-4% F.

Abstract: This invention is concerned with hydrated glass articles having base compositions within the Na.sub.2 O and/or K.sub.2 O-ZnO-Al.sub.2 O.sub.3 -SiO.sub.2 -Cl field and having at least a surface layer thereon containing Ag-AgCl crystals which impart photo-anisotropic effects to the glass articles. Silver ions are introduced into the surface layer through a solution ion exchange process with sodium and/or potassium ions of the parent glass. The silver remains in the ionic state until exposure to ultraviolet radiation which results in the development of silver-containing aggregates, i.e., Ag-AgCl, via a photolytic reaction. The aggregates contribute to photo-anisotropic absorption bands which are centered around 340 nm and 700 nm. Polarization of the photo-dichroic and photo-birefringent effects of the inventive products can be altered reversibly between two arbitrary directions without fatigue. The photo-anisotropic image can be read cyclically essentially indefinitely without destruction.

Abstract: The present invention is related to the production of crystal-containing gels and papers, films, fibers, boards, and coatings made therefrom. The process for making the gels comprises three general steps: first, a fully or predominantly crystalline body is formed containing crystals consisting essentially of a lithium and/or sodium water-swelling mica selected from the group of fluorhectorite, hydroxyl hectorite, boron fluorphlogopite, hydroxyl boron phlogopite, and solid solutions among those and between those and other structurally-compatible species selected from the group of talc, fluortalc, polylithionite, fluorpolylithionite, phlogopite, and fluorphlogopite; second, that body is contacted with a polar liquid, desirably water, to cause swelling and disintegration of the body accompanied with the formation of a gel; and, third, the solid:liquid ratio of the gel is adjusted to a desired value depending upon the application therefor.

Abstract: The instant invention is directed to a method for writing and erasing images in the surface of a photosensitive glass which demonstrates photoanisotropic behavior at a mega Hz or higher rate. This is accomplished by utilizing an erasing beam of linearly-polarized red light having about a 45.degree. change in the direction of polarization from that of the writing beam. Also, this invention provides a method for preventing the alteration of an image written into said glass surface, the method involving exposing the area of the image to ultraviolet radiation.

Abstract: There is disclosed a method of producing an image of an original multi-color subject in polychromatic glass by employing as a masking means, during initial exposure of the glass, high contrast film positives embodying the subject in the form of half tone transparencies. Preparation of the film positives for masking purposes is also described.

Abstract: The subject invention is related to the preparation of ceramic bodies wherein the crystal phase consists essentially of cesium-stuffed, hexagonal cordierite. The bodies are capable of use temperatures up to 1600.degree. C., exhibit nearly isotropic axial thermal expansions, and consist essentially, expressed in weight percent on the oxide basis, of about 11-13% MgO, 34-36% Al.sub.2 O.sub.3, 33-42% SiO.sub.2, and 10-22% Cs.sub.2 O.

Abstract: The instant invention is concerned with a method for producing shades of a tint in a photochromic glass, the hue of which will be essentially permanent even after subjecting the glass to temperatures up to about the strain point of the glass. Silver halide crystals constitute the photochromic agents, the glass contains lead, and the method contemplates exposing such a glass to a gaseous reducing atmosphere at temperatures above the strain point of the glass to cause the reduction of silver ions to metallic silver and the reduction of lead ions to metallic lead which coats or alloys with the metallic silver.

Abstract: A method and apparatus for edge-grinding stressed laminated glass-plastic lens blanks wherein the lens blanks are heated during the abrasive edging process to reduce thermal stress breakage. The edged lenses are optionally etched to remove glass flaws, thus providing laminated lenses exhibiting improved resistance to thermal stress breakage in use.