Annealing treatments for modified titania-silica glasses and the glasses produced by the annealing treatments. The annealing treatments include an isothermal hold that facilitates equalization of non-uniformities in fictive temperature caused by non-uniformities in modifier concentration in the glasses. The annealing treatments may also include heating the glass to a higher temperature following the isothermal hold and holding the glass at that temperature for several hours. Glasses produced by the annealing treatments exhibit high spatial uniformity of CTE, CTE slope, and fictive temperature, including in the presence of a spatially non-uniform concentration of modifier.

Annealing treatments for modified titania-silica glasses and the glasses produced by the annealing treatments. The annealing treatments include an isothermal hold that facilitates equalization of non-uniformities in fictive temperature caused by non-uniformities in modifier concentration in the glasses. The annealing treatments may also include heating the glass to a higher temperature following the isothermal hold and holding the glass at that temperature for several hours. Glasses produced by the annealing treatments exhibit high spatial uniformity of CTE, CTE slope, and fictive temperature, including in the presence of a spatially non-uniform concentration of modifier.

Lithium silicate glass ceramics and glasses containing specific oxides of divalent elements are described which crystallize at low temperatures and are suitable in particular as dental materials.

Lithium silicate glass ceramics and glasses containing specific oxides of divalent elements are described which crystallize at low temperatures and are suitable in particular as dental materials.

To provide a glass plate which is hardly broken and which has a high infrared transmittance.

A glass plate, which has a thickness of from 1 to 8 mm, has an infrared transmittance T3000 at a wavelength of 3,000 nm of at least 4%, an average thermal expansion coefficient a at from 50 to 350° C. of from 15 to 35×10.sup.−7/° C., and a glass composition comprising, as represented by mol% based on oxides, from 50 to 85% of SiO.sub.2, from 0.1 to 25% of Al.sub.2O.sub.3, from 0.1 to 20% of B.sub.2O.sub.3, from 0 to 20% in total of at least one member selected from MgO, CaO, SrO, BaO and ZnO, and from 0 to 20% in total of at least one member selected from Li.sub.2O, Na.sub.2O and K.sub.2O.

To provide a glass plate which is hardly broken and which has a high infrared transmittance.

A glass plate, which has a thickness of from 1 to 8 mm, has an infrared transmittance T3000 at a wavelength of 3,000 nm of at least 4%, an average thermal expansion coefficient a at from 50 to 350° C. of from 15 to 35×10.sup.−7/° C., and a glass composition comprising, as represented by mol% based on oxides, from 50 to 85% of SiO.sub.2, from 0.1 to 25% of Al.sub.2O.sub.3, from 0.1 to 20% of B.sub.2O.sub.3, from 0 to 20% in total of at least one member selected from MgO, CaO, SrO, BaO and ZnO, and from 0 to 20% in total of at least one member selected from Li.sub.2O, Na.sub.2O and K.sub.2O.

A copper dopant delivery powder comprising a fused silica powder and a Cu.sub.2S powder. A method of making the copper dopant delivery powder. A method of making a copper-doped glass comprising placing a target glass in a container, packing a composite SiO.CuS dopant powder around the target glass and heating the container and SiO.CuS dopant powder to a temperature of between 800° C. and 1150° C. A copper-doped glass comprising a glass comprising copper-doping wherein the copper-doped glass was formed by covering the glass with a fused silica powder and a Cu.sub.2S powder, wherein the fused silica powder and the Cu.sub.2S powder are mixed in varying ratios of Cu.sub.2S to silica represented by the formula (SiO.sub.2).sub.(1-x)(Cu.sub.2S).sub.x and heating to a temperature of between 800° C. and 1150° C.

A single mode optical fiber having a core made from silica and less than or equal to about 11 weight % germania and having a maximum relative refractive index Δ.sub.1MAX. The optical fiber also has an inner cladding surrounding the core and having a minimum relative refractive index Δ.sub.2MIN, a first outer cladding surrounding the inner cladding and a second outer cladding surrounding the first outer cladding. The viscosity at 1650° C. of the second outer cladding minus the viscosity at 1650° C. of the first outer cladding is greater than 0.1e.sup.7 Poise, and Δ.sub.1MAX>Δ.sub.2MIN. The single mode optical fiber may also have an outer cladding surrounding the inner cladding made from silica or SiON. The first outer cladding has a maximum relative refractive index Δ.sub.3MAX, and Δ.sub.3MAX>Δ.sub.2MIN.

A single mode optical fiber having a core made from silica and less than or equal to about 11 weight % germania and having a maximum relative refractive index Δ.sub.1MAX. The optical fiber also has an inner cladding surrounding the core and having a minimum relative refractive index Δ.sub.2MIN, a first outer cladding surrounding the inner cladding and a second outer cladding surrounding the first outer cladding. The viscosity at 1650° C. of the second outer cladding minus the viscosity at 1650° C. of the first outer cladding is greater than 0.1e.sup.7 Poise, and Δ.sub.1MAX>Δ.sub.2MIN. The single mode optical fiber may also have an outer cladding surrounding the inner cladding made from silica or SiON. The first outer cladding has a maximum relative refractive index Δ.sub.3MAX, and Δ.sub.3MAX>Δ.sub.2MIN.

A photosensitive conductive paste that contains(a) a conductive powder in an amount of 70.3 to 85.6 mass % with respect to the total amount of the photosensitive conductive paste; (b) a photosensitive resin composition containing an alkali-soluble polymer, a photosensitive monomer, a pnotopolym.erization initiator, and a solvent; and (c) a glass frit. The mass ratio of the glass frit to the conductive powder is 0.020 to 0.054, and the glass frit has a softening point that is equal to or above the temperature at which sintering of the conductive powder starts.