Abstract: A transparent glass which, at a thickness of 2 mm, transmits less than 1% of ultraviolet radiation having a wavelength of 380 nm and exhibits a brown fixed tint bounded by apices A, B, D, F, A of the drawing, a purity between 48-70%, and a dominant wavelength between 580-588 nm, said glass having a composition consisting essentially, expressed in terms of weight percent on the oxide basis, of______________________________________ SiO.sub.2 65-72 CaO 0-5.5 B.sub.2 O.sub.3 3-8 ZnO 0-4 Na.sub.2 O 6-10 CaO + ZnO 2-5.5 K.sub.2 O 7-12 Fe.sub.2 O.sub.3 3-5 Na.sub.2 O + K.sub.2 O 15-20 Se 0.01-2 Al.sub.2 O.sub.3 0-4 NiO 0-0.12.

Abstract: This invention is directed to the production of transparent glasses which can be chemically strengthened within a period of time not exceeding four hours to develop a surface compression layer having a sufficient depth to survive the Drop Ball Test after abrasion, the glasses consisting essentially, in weight percent, of______________________________________ SiO.sub.2 55-65 CaO 0-1.5 B.sub.2 O.sub.3 5-20 MgO 0-4 Al.sub.2 O.sub.3 4-10 TiO.sub.2 0-4 B.sub.2 O.sub.3 + Al.sub.2 O.sub.3 14-26 ZrO.sub.2 0-7 Li.sub.2 O 0-3 MgO + TiO.sub.2 + ZrO.sub.2 0-10 Na.sub.2 O 6-18 As.sub.2 O.sub.3 0-0.5 K.sub.2 O 2-10 ZnO 0-1.5 Li.sub.2 O + Na.sub.2 O + K.sub.2 O 13-22. ______________________________________Where desired, 3.5-5.5% Fe.sub.2 O.sub.3 may be included to yield glasses which, at a thickness of 2 mm, will not transmit more than 1% of ultraviolet radiation at a wavelength of 380 nm. Where an ultraviolet absorbing glass exhibiting a neutral gray, fixed tint is desired, 0.02-0.035% Co.sub.3 O.sub.4 and 0.08-0.

Abstract: A transparent glass which, at a thickness of 2 mm, does not transmit more than about 1% of ultraviolet radiation at a wavelength of 380 nm and exhibits a neutral gray, fixed tint bounded by apices A, B, C, D, A of the drawing, a purity no higher than 6, and a luminous transmittance between 10-16, said glass having a composition consisting essentially, expressed in terms of weight percent on the oxide basis, of______________________________________ SiO.sub.2 65-72 CaO 0-1.5 B.sub.2 O.sub.3 2-6 Al.sub.2 O.sub.3 + CaO 0.2-2.25 Na.sub.2 O 6-10 As.sub.2 O.sub.3 0-0.3 K.sub.2 O 10-16 Fe.sub.2 O.sub.3 4.8-6.2 Na.sub.2 O + K.sub.2 O 17-23 Co.sub.3 O.sub.4 0.012-0.02 K.sub.2 O:Na.sub.2 O 1.25-2.25 NiO 0.16-0.21 Al.sub.2 O.sub.3 0-2.25 ZnO 0-1.5.

Abstract: A silver halide photochromic glass hasa. a clear luminous transmittance of about 90%,b. A darkened luminous transmittance at 20.degree. C. below about 25%.c. A fading rate at 20.degree. C. such that, after a five minute fading interval, the glass exhibits a percent faded luminous transmittance that is no more than the darkened luminous transmittance percentage plus 15. The glass has an R.sub.2 O--Al.sub.2 O.sub.3 --B.sub.2 O.sub.3 --SiO.sub.2 base composition, contains as additives, in percent by weight, 0.1-0.3% Ag, 0.25-1.0% Cl, 0-0.2% Br, 0.25-1.0% Cl+Br, the ratio of Ag:(Cl+Br) being 0.15-0.65, 0.003-0.015% CuO and 0.1-1.0% PbO and the total R.sub.2 O content is 8-13.5%, wherein R.sub.2 O consists of Li.sub.2 O+Na.sub.2 O +K.sub.2 O.

Abstract: A composition for a photochromic glass consisting essentially of, in approximate calculated weight percent, about:______________________________________ SiO.sub.2 54-58% Ag 0.18-0.33% B.sub.2 O.sub.3 18-22% Cl 0.25-0.50% Al.sub.2 O.sub.3 7-8% Br 0.04-0.12% Li.sub.2 O 3.75-4.5% CuO 0.007-0.012% Na.sub.2 O 0-1% PbO 0-0.08% K.sub.2 O 5.5-7.5% Sb.sub.2 O.sub.3 0-0.20% TiO.sub.2 0-2% Pd 1-6 ppm ZrO.sub.2 2-4.5% ______________________________________plus 0-1.0% Er.sub.2 O.sub.3 and/or 0-10 ppm Au, the mole ratio of Li.sub.2 O:Na.sub.2 O being equal to or greater than 9:1 and the glass having a coloration in the fully darkened state corresponding to chromaticity coordinates, in accordance with the 1931 C.I.E. trichromatic colorimetric system, that fall within the trapezoid ABCDA in the drawing for a 1.1 mm glass thickness, and within the trapezoid EFGHE for a 2 mm glass thickness.

Abstract: A method of producing a glass-plastic, laminated, ophthalmic lens structure in a continuous operation. A thin, flexible, plastic adhesive layer is applied to a glass element to form a composite body that is inserted in a cylindrical gasket in such manner as to fit snugly and be sealed from the ambient. A monomeric formulation is flowed onto the adhesive layer and cured to form a laminated lens blank.

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 is directed to a method for heat treating a sheet of a potentially photochromic glass to cause the growth of silver halide crystals therein which impart photochromic properties thereto, wherein the heat treated sheet will be essentially free from thermal deformation and surface defects, and the photochromic properties exhibited therein will be essentially uniform across the area of the sheet. The method involves first placing a sheet of potentially photochromic glass on top of a sheet of carrier glass that exhibits a softening point at least 50.degree. C. higher than the temperature at which the potentially photochromic glass will be heat treated, and thereafter subjecting the stacked sheets to the heat treatment temperature desired for growing silver halide crystals in the glass.

Abstract: Photochromic glass compositions for thin refractive-index-corrected lens elements consisting essentially of about:______________________________________ SiO.sub.2 54-58% B.sub.2 O.sub.3 18-22% Al.sub.2 O.sub.3 7-8% Li.sub.2 O 3.75-4.5% Na.sub.2 O 0-1% K.sub.2 O 5.5-7.5% TiO.sub.2 0-2% ZrO.sub.2 2-4.5% Ag 0.20-0.33% Cl 0.30-0.50% Br 0.04-0.12% CuO 0.007-0.012% PbO 0-0.08% Sb.sub.2 O.sub.3 0-0.20% ______________________________________having a Li.sub.2 O:Na.sub.2 O molar ratio of at least 9:1 and exhibiting good darkening, fast fading, good chemical strengthenability and neutral dark-state coloration at thicknesses on the order of 1 mm, are described.

Abstract: This invention is directed to the preparation of haze-free photochromic glasses which darken to a comfort range, i.e., a luminous transmittance of about 40-60%, which exhibit very rapid fading, and which demonstrate excellent temperature dependence. The glasses consist essentially, in weight percent with the levels of Ag, Cu.sub.2 0, C1, and Br representing values as analyzed in the glass, of:______________________________________ Li.sub.2 O 0-2.5 P.sub.2 O.sub.5 0-25 Na.sub.2 O 0-9 SiO.sub.2 20-65 K.sub.2 O 0-17 Ag 0.115-0.145 Cs.sub.2 O 0-6 Br 0.11-0.155 Li.sub.2 O + Na.sub.2 O + K.sub.2 O + Cs.sub.2 O 8-20 B.sub.2 O.sub.3 14-23 Cu.sub.2 O 0.007-0.011 Al.sub.2 O.sub.3 5-25 Cl 0.1-0.15 ______________________________________and wherein the molar ratio alkali metal oxide: B.sub.2 0.sub.3 ranges between about 0.55-0.85, the weight ratio Ag:(C1+Br) ranges between about 0.65-0.95, and the sum of Ag+Br is at least 0.26%, when the Br content is 0.11%, and at least 0.25% when the Ag content is 0.115%.

Abstract: There is disclosed a method of producing a photochromic glass having a reduced transmittance for ultraviolet radiation while having substantially unimpaired photochromic properties. The method comprises providing a combination of 0.1-1.0% CeO.sub.2 and 0.1-1.5% Sb.sub.2 O.sub.3 and/or As.sub.2 O.sub.3 as part of the glass composition. In an embodiment utilizing minimal silver content, the glass article in thicknesses of 1.3 to 2.0 mm. can be chemically strengthened to surpass the impact specification imposed by the Federal Food and Drug Administration for eyewear, will transmit less than 0.2% of radiation having wavelengths between 290-315 nm, and will demonstrate a darkened luminous transmittance at 20.degree.-25.degree. C. below 35% and a fading rate such that after five minutes the luminous transmittance will be at least 1.75 times that of the darkened transmittance. These glasses consist essentially of:______________________________________ SiO.sub.2 55-61 Ag >0.1-<0.2 B.sub.2 O.sub.3 18-21 Cl 0.

Abstract: The present invention is directed to the preparation of photochromic glasses exhibiting a darkened luminous transmittance at 40.degree. C. below 35% and a five-minute fading rate at 40.degree. C. of at least 40 units of transmittance and a darkened transmittance at 25.degree. C. below 25% and a five-minute fading rate at 25.degree. C. of at least 35 units of transmittance. The glasses consist essentially, by weight, of:______________________________________ SiO.sub.2 56-60 Al.sub.2 O.sub.3 6-9 B.sub.2 O.sub.3 18-21 Li.sub.2 O >2.5-3.5 Na.sub.2 O 0.5-2.5 K.sub.2 O 5-7 ZrO.sub.2 3.75-5 PbO 0.1-0.15 Ag >0.15-0.25 Cl 0.2-0.35 Br 0.075-0.15 CuO 0.004-0.02 CeO.sub.2 0-0.5 ______________________________________wherein the levels of Ag, Br, Cl, and CuO represent values as analyzed in the glass.

Abstract: The present invention is concerned with the production of photochromic glass compositions consisting essentially, expressed in terms of weight percent on the oxide basis, as calculated from the batch, of______________________________________ SiO.sub.2 52-59 B.sub.2 O.sub.3 18-23 Al.sub.2 O.sub.3 6-8 Li.sub.2 O 1-2.5 Na.sub.2 O 1-3 K.sub.2 O 8-13 ZrO.sub.2 2-6 TiO.sub.2 0-3 ______________________________________and containing, as analyzed in weight percent, of ______________________________________ Ag 0.17-0.22 CuO 0.012-0.019 Cl 0.29-0.35 Br 0.06-0.12 PbO 0.1-0.15 ______________________________________exhibiting, in 0.4 mm cross section, a clear luminous transmittance in excess of 90%, a darkened luminous transmittance below about 45% at a temperature of 25.degree. C., a darkened luminous transmittance below about 57% at a temperature of 40.degree. C., and a half fading time at both temperatures of about five minutes.

Abstract: The instant invention is directed to the production of photochromic glasses having compositions consisting essentially, as analyzed in weight percent on the oxide basis, ofSiO.sub.2 --55-60Al.sub.2 O.sub.3 --9-10B.sub.2 O.sub.3 --19-20.5Li.sub.2 O--2-2.5Na.sub.2 O--2-3K.sub.2 O--6-7PbO--0.1-0.25Ag--0.1-0.15Cl--0.3-0.5Br--0.05-0.15CuO--0.0065-0.01The glasses are capable of being drawn into sheet and articles cut from the sheet simultaneously shaped and photochromic properties developed therein. The glasses display a clear luminous transmittance in excess of 90% when free from tint, a darkened luminous transmittance at 20.degree. C. below 25% when free from tint, and a fading rate at 20.degree. C. such that the glass demonstrates a faded luminous transmittance at least twice that of the darkened transmittance after a five-minute fading interval.

Abstract: This invention is directed to the production of photochromic glass microsheet which is particularly useful in the fabrication of transparent glass-plastic composite lenses. In such lenses, the photochromic microsheet will either be buried within the plastic or will act as a surface layer thereon. The microsheet consists essentially, in weight percent on the oxide basis as calculated from the batch, of 54-66% SiO.sub.2, 7-15% Al.sub.2 O.sub.3, 10-30% B.sub.2 O.sub.3, 3-15% Na.sub.2 O, 0.4-1.5% PbO, 0.2-0.5% Br, 0.5-1.2% Cl, 0.2-0.5% F, 0.008-0.03% CuO, and >0.03%-1% Ag.

Abstract: Chemically-strengthenable silver halide-containing lithium boroaluminosilicate glass compositions having physical and chemical characteristics required for sheet drawing processes and exhibiting excellent photochromic properties after heat treatment, and also strengthened photochromic drawn sheet glass articles provided therefrom, are described.

Abstract: Copper, cadmium, silver and halogen-containing glass compositions suitable for the production of photochromic glass articles comprising these constituents in a separated, particulate photochromic phase are described. The glasses exhibit a characteristic copper-cadmium halide absorption inflection in the near ultraviolet, and are surface-darkenable on exposure to ultraviolet and short-wavelength visible light. However, they also exhibit optical bleaching characteristics and a variety of dark-state colors not previously obtained in surface darkening glasses.

Abstract: A silver-halide photochromic glass of alkali-boroaluminosilicate base composition, having a brown coloration in the faded and darkened state, is provided by treating a potentially photochromic glass of specified composition according to a defined two-phase heat treatment to develop photochromic properties therein.

Abstract: Chemically-strengthenable silver halide-containing lithium boroaluminosilicate glass compositions having physical and chemical characteristics required for sheet drawing processes and exhibiting excellent photochromic properties after heat treatment, and also strengthened photochromic drawn sheet glass articles provided therefrom, are described.

Abstract: Photochromic glasses having index of refraction values (n.sub.D) in the range from 1.52-1.54, compositions comprising, in weight percent, about 49-60% SiO.sub.2, 2-9% Al.sub.2 O.sub.3, 15-18% B.sub.2 O.sub.3, 6-12% Na.sub.2 O, 9-18% ZrO.sub.2, 0.5-0.9% Ag, 0.5-0.8% Cl, 0.010-0.030% CuO, 0.5-1% PbO, and 1-2% F, and rapid fading characteristics such that at least about 65% of the optical density gained during darkening is lost within a five-minute fading interval, are disclosed.