Abstract:
The present invention improves the luminous efficiency of lamps that emit light due to electric discharge, such as a fluorescent lamp and an HID lamp. The fluorescent lamp includes a glass tube used as a fluorescent tube made of a glass material containing an emissive element. When exposed to ultraviolet light (with the peak wavelength of 251 nm) emitted due to mercury excitation, the emissive element emits ultraviolet light having a longer wavelength than that. The HID lamp includes an envelop made of a glass material that contains an emissive element. When exposed to ultraviolet light emitted due to excitation of an emissive material enclosed in an arc tube, the emissive element emits ultraviolet light having a longer wavelength than that.
Abstract:
A phosphor layer is composed of tri-band phosphor particles bound together by a binder. A material as the main component of the binder is a mixture of (1) a compound formed by calcium oxide, barium oxide, and boron oxide, and (2) calcium pyrophosphate. Dissolved in the main component material of the binder is a luminescent component that converts ultraviolet radiation of 254 nm to ultraviolet radiation of longer wavelengths or to visible light. Examples of such a luminescent component include an oxide of gadolinium (Gd), terbium (Tb), europium (Eu), neodymium (Nd), or dysprosium (Dy), each of which belongs to lanthanum series, and an oxide of thallium (Tl), tin (Sn), lead (Pb), or bismuth (Bi).
Abstract:
A glass composition for lamps includes: SiO2 (silicon dioxide) as a main component; Na2O (sodium oxide) in the range of 12 to 17 wt. %; MgO (magnesium oxide) in the range of 2.5 to 4 wt. %; and CaO (calcium oxide) in the rage of 5.3 to 7.3 wt. %, wherein the total content of MgO and CaO is in the range of 8 to 11 wt. %. Thereby, lamps can be manufactured at relatively low costs that exhibit superiority in fracture resistance, workability, erosion resistance with respect to the inner surface of a furnace, and suppressing the elution of alkali component.
Abstract:
To suppress breakage of glass for an electric lamp in a process in which the glass that has already been formed is processed further, a glass composition for an electric lamp is provided. The glass composition contains, expressed in mol %, 70 to 85% of SiO2, 12 to 17% of R2O, and 2 to 8.5% of MO (where R represents at least one selected from Li, Na and K, and M represents at least one selected from Mg, Ca, Sr, Ba, Zn and Pb). In the glass composition, the respective contents of CaO, MgO, BaO and SrO satisfy the relationship, CaO+MgO>BaO+SrO. The glass composition has a brittleness index value B determined by the Vickers hardness test of 7,000 m−1/2. Preferably, the contents of SrO and BaO are 0 to 0.5% and 0.1 to 1%, respectively. More preferably, the respective contents of K2O and Na2O satisfy the relationship, K2O>Na2O.